* [PATCH net-next v4 00/15] Add Management Component Transport Protocol support
@ 2021-07-29 2:20 Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 01/15] mctp: Add MCTP base Jeremy Kerr
` (15 more replies)
0 siblings, 16 replies; 23+ messages in thread
From: Jeremy Kerr @ 2021-07-29 2:20 UTC (permalink / raw)
To: netdev
Cc: Matt Johnston, Andrew Jeffery, Jakub Kicinski, David S. Miller,
linux-doc, Jonathan Corbet, Paul Moore, Stephen Smalley,
Eric Paris, selinux
This series adds core MCTP support to the kernel. From the Kconfig
description:
Management Component Transport Protocol (MCTP) is an in-system
protocol for communicating between management controllers and
their managed devices (peripherals, host processors, etc.). The
protocol is defined by DMTF specification DSP0236.
This option enables core MCTP support. For communicating with other
devices, you'll want to enable a driver for a specific hardware
channel.
This implementation allows a sockets-based API for sending and receiving
MCTP messages via sendmsg/recvmsg on SOCK_DGRAM sockets. Kernel stack
control is all via netlink, using existing RTM_* messages. The userspace
ABI change is fairly small; just the necessary AF_/ETH_P_/ARPHDR_
constants, a new sockaddr, and a new netlink attribute.
For MAINTAINERS, I've just included netdev@ as the list entry. I'm happy
to alter this based on preferences here - an alternative would be the
OpenBMC list (the main user of the MCTP interface), or we can create a
new list entirely.
We have a couple of interface drivers almost ready to go at the moment,
but those can wait until the core code has some review.
This is v4 of the series; v1 and v2 were both RFC.
selinux folks: CCing 01/15 due to the new PF_MCTP protocol family.
linux-doc folks: CCing 15/15 for the new MCTP overview document.
Review, comments, questions etc. are most welcome.
Cheers,
Jeremy
v2:
- change to match spec terminology: controller -> component
- require specific capabilities for bind() & sendmsg()
- add address and tag defintions to uapi
- add selinux AF_MCTP table definitions
- remove strict cflags; warnings are present in common headers
v3:
- require caps for MCTP bind() & send()
- comment typo fixes
- switch to an array for local EIDs
- fix addrinfo dump iteration & error path
- add RTM_DELADDR
- remove GENMASK() and BIT() from uapi
v4:
- drop tun patch; that can be submitted separately
- keep nipa happy: add maintainer CCs, including doc and selinux
- net-next rebase
- Include AF_MCTP in af_family_slock_keys and pf_family_names
- Introduce MODULE_ definitions earlier
- upstream change: set_link_af no longer called with RTNL held
- add kdoc for net_device.mctp_ptr
- don't inline mctp_rt_match_eid
- require rtm_type == RTN_UNICAST in route management handlers
- remove unused RTAX policy table
- fix mctp_sock->keys rcu annotations
- fix spurious rcu_read_unlock in route input
Jeremy Kerr (10):
mctp: Add MCTP base
mctp: Add base socket/protocol definitions
mctp: Add base packet definitions
mctp: Add sockaddr_mctp to uapi
mctp: Add initial driver infrastructure
mctp: Add device handling and netlink interface
mctp: Add initial routing framework
mctp: Populate socket implementation
mctp: Implement message fragmentation & reassembly
mctp: Add MCTP overview document
Matt Johnston (6):
mctp: Add netlink route management
mctp: Add neighbour implementation
mctp: Add neighbour netlink interface
mctp: Add dest neighbour lladdr to route output
mctp: Allow per-netns default networks
mctp: Allow MCTP on tun devices
Documentation/networking/index.rst | 1 +
Documentation/networking/mctp.rst | 213 ++++++
MAINTAINERS | 12 +
drivers/net/Kconfig | 2 +
drivers/net/Makefile | 1 +
drivers/net/mctp/Kconfig | 8 +
drivers/net/mctp/Makefile | 0
include/linux/netdevice.h | 3 +
include/linux/socket.h | 6 +-
include/net/mctp.h | 235 ++++++
include/net/mctpdevice.h | 36 +
include/net/net_namespace.h | 4 +
include/net/netns/mctp.h | 36 +
include/uapi/linux/if_arp.h | 1 +
include/uapi/linux/if_ether.h | 3 +
include/uapi/linux/if_link.h | 10 +
include/uapi/linux/mctp.h | 36 +
net/Kconfig | 1 +
net/Makefile | 1 +
net/mctp/Kconfig | 13 +
net/mctp/Makefile | 3 +
net/mctp/af_mctp.c | 396 ++++++++++
net/mctp/device.c | 427 +++++++++++
net/mctp/neigh.c | 342 +++++++++
net/mctp/route.c | 1095 +++++++++++++++++++++++++++
security/selinux/hooks.c | 4 +-
security/selinux/include/classmap.h | 4 +-
27 files changed, 2890 insertions(+), 3 deletions(-)
create mode 100644 Documentation/networking/mctp.rst
create mode 100644 drivers/net/mctp/Kconfig
create mode 100644 drivers/net/mctp/Makefile
create mode 100644 include/net/mctp.h
create mode 100644 include/net/mctpdevice.h
create mode 100644 include/net/netns/mctp.h
create mode 100644 include/uapi/linux/mctp.h
create mode 100644 net/mctp/Kconfig
create mode 100644 net/mctp/Makefile
create mode 100644 net/mctp/af_mctp.c
create mode 100644 net/mctp/device.c
create mode 100644 net/mctp/neigh.c
create mode 100644 net/mctp/route.c
--
2.30.2
Jeremy Kerr (10):
mctp: Add MCTP base
mctp: Add base socket/protocol definitions
mctp: Add base packet definitions
mctp: Add sockaddr_mctp to uapi
mctp: Add initial driver infrastructure
mctp: Add device handling and netlink interface
mctp: Add initial routing framework
mctp: Populate socket implementation
mctp: Implement message fragmentation & reassembly
mctp: Add MCTP overview document
Matt Johnston (5):
mctp: Add netlink route management
mctp: Add neighbour implementation
mctp: Add neighbour netlink interface
mctp: Add dest neighbour lladdr to route output
mctp: Allow per-netns default networks
Documentation/networking/index.rst | 1 +
Documentation/networking/mctp.rst | 213 ++++++
MAINTAINERS | 12 +
drivers/net/Kconfig | 2 +
drivers/net/Makefile | 1 +
drivers/net/mctp/Kconfig | 8 +
drivers/net/mctp/Makefile | 0
include/linux/netdevice.h | 4 +
include/linux/socket.h | 6 +-
include/net/mctp.h | 231 ++++++
include/net/mctpdevice.h | 36 +
include/net/net_namespace.h | 4 +
include/net/netns/mctp.h | 36 +
include/uapi/linux/if_arp.h | 1 +
include/uapi/linux/if_ether.h | 3 +
include/uapi/linux/if_link.h | 10 +
include/uapi/linux/mctp.h | 36 +
net/Kconfig | 1 +
net/Makefile | 1 +
net/core/sock.c | 1 +
net/mctp/Kconfig | 13 +
net/mctp/Makefile | 3 +
net/mctp/af_mctp.c | 396 ++++++++++
net/mctp/device.c | 423 +++++++++++
net/mctp/neigh.c | 342 +++++++++
net/mctp/route.c | 1099 +++++++++++++++++++++++++++
net/socket.c | 1 +
security/selinux/hooks.c | 4 +-
security/selinux/include/classmap.h | 4 +-
29 files changed, 2889 insertions(+), 3 deletions(-)
create mode 100644 Documentation/networking/mctp.rst
create mode 100644 drivers/net/mctp/Kconfig
create mode 100644 drivers/net/mctp/Makefile
create mode 100644 include/net/mctp.h
create mode 100644 include/net/mctpdevice.h
create mode 100644 include/net/netns/mctp.h
create mode 100644 include/uapi/linux/mctp.h
create mode 100644 net/mctp/Kconfig
create mode 100644 net/mctp/Makefile
create mode 100644 net/mctp/af_mctp.c
create mode 100644 net/mctp/device.c
create mode 100644 net/mctp/neigh.c
create mode 100644 net/mctp/route.c
--
2.30.2
Jeremy Kerr (10):
mctp: Add MCTP base
mctp: Add base socket/protocol definitions
mctp: Add base packet definitions
mctp: Add sockaddr_mctp to uapi
mctp: Add initial driver infrastructure
mctp: Add device handling and netlink interface
mctp: Add initial routing framework
mctp: Populate socket implementation
mctp: Implement message fragmentation & reassembly
mctp: Add MCTP overview document
Matt Johnston (5):
mctp: Add netlink route management
mctp: Add neighbour implementation
mctp: Add neighbour netlink interface
mctp: Add dest neighbour lladdr to route output
mctp: Allow per-netns default networks
Documentation/networking/index.rst | 1 +
Documentation/networking/mctp.rst | 213 ++++++
MAINTAINERS | 12 +
drivers/net/Kconfig | 2 +
drivers/net/Makefile | 1 +
drivers/net/mctp/Kconfig | 8 +
drivers/net/mctp/Makefile | 0
include/linux/netdevice.h | 4 +
include/linux/socket.h | 6 +-
include/net/mctp.h | 231 ++++++
include/net/mctpdevice.h | 36 +
include/net/net_namespace.h | 4 +
include/net/netns/mctp.h | 36 +
include/uapi/linux/if_arp.h | 1 +
include/uapi/linux/if_ether.h | 3 +
include/uapi/linux/if_link.h | 10 +
include/uapi/linux/mctp.h | 36 +
net/Kconfig | 1 +
net/Makefile | 1 +
net/core/sock.c | 1 +
net/mctp/Kconfig | 13 +
net/mctp/Makefile | 3 +
net/mctp/af_mctp.c | 396 ++++++++++
net/mctp/device.c | 423 +++++++++++
net/mctp/neigh.c | 342 +++++++++
net/mctp/route.c | 1099 +++++++++++++++++++++++++++
net/socket.c | 1 +
security/selinux/hooks.c | 4 +-
security/selinux/include/classmap.h | 4 +-
29 files changed, 2889 insertions(+), 3 deletions(-)
create mode 100644 Documentation/networking/mctp.rst
create mode 100644 drivers/net/mctp/Kconfig
create mode 100644 drivers/net/mctp/Makefile
create mode 100644 include/net/mctp.h
create mode 100644 include/net/mctpdevice.h
create mode 100644 include/net/netns/mctp.h
create mode 100644 include/uapi/linux/mctp.h
create mode 100644 net/mctp/Kconfig
create mode 100644 net/mctp/Makefile
create mode 100644 net/mctp/af_mctp.c
create mode 100644 net/mctp/device.c
create mode 100644 net/mctp/neigh.c
create mode 100644 net/mctp/route.c
--
2.30.2
^ permalink raw reply [flat|nested] 23+ messages in thread
* [PATCH net-next v4 01/15] mctp: Add MCTP base
2021-07-29 2:20 [PATCH net-next v4 00/15] Add Management Component Transport Protocol support Jeremy Kerr
@ 2021-07-29 2:20 ` Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 02/15] mctp: Add base socket/protocol definitions Jeremy Kerr
` (14 subsequent siblings)
15 siblings, 0 replies; 23+ messages in thread
From: Jeremy Kerr @ 2021-07-29 2:20 UTC (permalink / raw)
To: netdev
Cc: Matt Johnston, Andrew Jeffery, Jakub Kicinski, David S. Miller,
Paul Moore, Stephen Smalley, Eric Paris, selinux
Add basic Kconfig, an initial (empty) af_mctp source object, and
{AF,PF}_MCTP definitions, and the required definitions for a new
protocol type.
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
---
v2:
- Add Linux-syscall-note to uapi header
- Add selinux defs for new AF_MCTP
- Controller -> component
- Don't use strict cflags; warnings are present in #includes
v4:
- Include AF_MCTP in af_family_slock_keys and pf_family_names
- Introduce MODULE_ definitions earlier
---
MAINTAINERS | 7 +++++++
include/linux/socket.h | 6 +++++-
include/uapi/linux/mctp.h | 15 +++++++++++++++
net/Kconfig | 1 +
net/Makefile | 1 +
net/core/sock.c | 1 +
net/mctp/Kconfig | 13 +++++++++++++
net/mctp/Makefile | 3 +++
net/mctp/af_mctp.c | 13 +++++++++++++
net/socket.c | 1 +
security/selinux/hooks.c | 4 +++-
security/selinux/include/classmap.h | 4 +++-
12 files changed, 66 insertions(+), 3 deletions(-)
create mode 100644 include/uapi/linux/mctp.h
create mode 100644 net/mctp/Kconfig
create mode 100644 net/mctp/Makefile
create mode 100644 net/mctp/af_mctp.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 4c32a9c532b7..22a1ff9afd9d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11032,6 +11032,13 @@ F: drivers/mailbox/arm_mhuv2.c
F: include/linux/mailbox/arm_mhuv2_message.h
F: Documentation/devicetree/bindings/mailbox/arm,mhuv2.yaml
+MANAGEMENT COMPONENT TRANSPORT PROTOCOL (MCTP)
+M: Jeremy Kerr <jk@codeconstruct.com.au>
+M: Matt Johnston <matt@codeconstruct.com.au>
+L: netdev@vger.kernel.org
+S: Maintained
+F: net/mctp/
+
MAN-PAGES: MANUAL PAGES FOR LINUX -- Sections 2, 3, 4, 5, and 7
M: Michael Kerrisk <mtk.manpages@gmail.com>
L: linux-man@vger.kernel.org
diff --git a/include/linux/socket.h b/include/linux/socket.h
index 0d8e3dcb7f88..fd9ce51582d8 100644
--- a/include/linux/socket.h
+++ b/include/linux/socket.h
@@ -223,8 +223,11 @@ struct ucred {
* reuses AF_INET address family
*/
#define AF_XDP 44 /* XDP sockets */
+#define AF_MCTP 45 /* Management component
+ * transport protocol
+ */
-#define AF_MAX 45 /* For now.. */
+#define AF_MAX 46 /* For now.. */
/* Protocol families, same as address families. */
#define PF_UNSPEC AF_UNSPEC
@@ -274,6 +277,7 @@ struct ucred {
#define PF_QIPCRTR AF_QIPCRTR
#define PF_SMC AF_SMC
#define PF_XDP AF_XDP
+#define PF_MCTP AF_MCTP
#define PF_MAX AF_MAX
/* Maximum queue length specifiable by listen. */
diff --git a/include/uapi/linux/mctp.h b/include/uapi/linux/mctp.h
new file mode 100644
index 000000000000..2640a589c14c
--- /dev/null
+++ b/include/uapi/linux/mctp.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Management Component Transport Protocol (MCTP)
+ *
+ * Copyright (c) 2021 Code Construct
+ * Copyright (c) 2021 Google
+ */
+
+#ifndef __UAPI_MCTP_H
+#define __UAPI_MCTP_H
+
+struct sockaddr_mctp {
+};
+
+#endif /* __UAPI_MCTP_H */
diff --git a/net/Kconfig b/net/Kconfig
index c7392c449b25..fb13460c6dab 100644
--- a/net/Kconfig
+++ b/net/Kconfig
@@ -363,6 +363,7 @@ source "net/bluetooth/Kconfig"
source "net/rxrpc/Kconfig"
source "net/kcm/Kconfig"
source "net/strparser/Kconfig"
+source "net/mctp/Kconfig"
config FIB_RULES
bool
diff --git a/net/Makefile b/net/Makefile
index 9ca9572188fe..fbfeb8a0bb37 100644
--- a/net/Makefile
+++ b/net/Makefile
@@ -78,3 +78,4 @@ obj-$(CONFIG_QRTR) += qrtr/
obj-$(CONFIG_NET_NCSI) += ncsi/
obj-$(CONFIG_XDP_SOCKETS) += xdp/
obj-$(CONFIG_MPTCP) += mptcp/
+obj-$(CONFIG_MCTP) += mctp/
diff --git a/net/core/sock.c b/net/core/sock.c
index a3eea6e0b30a..9671c32e6ef5 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -226,6 +226,7 @@ static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
x "AF_IEEE802154", x "AF_CAIF" , x "AF_ALG" , \
x "AF_NFC" , x "AF_VSOCK" , x "AF_KCM" , \
x "AF_QIPCRTR", x "AF_SMC" , x "AF_XDP" , \
+ x "AF_MCTP" , \
x "AF_MAX"
static const char *const af_family_key_strings[AF_MAX+1] = {
diff --git a/net/mctp/Kconfig b/net/mctp/Kconfig
new file mode 100644
index 000000000000..2cdf3d0a28c9
--- /dev/null
+++ b/net/mctp/Kconfig
@@ -0,0 +1,13 @@
+
+menuconfig MCTP
+ depends on NET
+ tristate "MCTP core protocol support"
+ help
+ Management Component Transport Protocol (MCTP) is an in-system
+ protocol for communicating between management controllers and
+ their managed devices (peripherals, host processors, etc.). The
+ protocol is defined by DMTF specification DSP0236.
+
+ This option enables core MCTP support. For communicating with other
+ devices, you'll want to enable a driver for a specific hardware
+ channel.
diff --git a/net/mctp/Makefile b/net/mctp/Makefile
new file mode 100644
index 000000000000..7c056b1b7939
--- /dev/null
+++ b/net/mctp/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_MCTP) += mctp.o
+mctp-objs := af_mctp.o
diff --git a/net/mctp/af_mctp.c b/net/mctp/af_mctp.c
new file mode 100644
index 000000000000..8f9c77e97357
--- /dev/null
+++ b/net/mctp/af_mctp.c
@@ -0,0 +1,13 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Management Component Transport Protocol (MCTP)
+ *
+ * Copyright (c) 2021 Code Construct
+ * Copyright (c) 2021 Google
+ */
+
+#include <linux/module.h>
+
+MODULE_DESCRIPTION("MCTP core");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Jeremy Kerr <jk@codeconstruct.com.au>");
diff --git a/net/socket.c b/net/socket.c
index 42665bd99ea4..3c10504e46d9 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -212,6 +212,7 @@ static const char * const pf_family_names[] = {
[PF_QIPCRTR] = "PF_QIPCRTR",
[PF_SMC] = "PF_SMC",
[PF_XDP] = "PF_XDP",
+ [PF_MCTP] = "PF_MCTP",
};
/*
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index b0032c42333e..2143f590e3d6 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -1330,7 +1330,9 @@ static inline u16 socket_type_to_security_class(int family, int type, int protoc
return SECCLASS_SMC_SOCKET;
case PF_XDP:
return SECCLASS_XDP_SOCKET;
-#if PF_MAX > 45
+ case PF_MCTP:
+ return SECCLASS_MCTP_SOCKET;
+#if PF_MAX > 46
#error New address family defined, please update this function.
#endif
}
diff --git a/security/selinux/include/classmap.h b/security/selinux/include/classmap.h
index 62d19bccf3de..084757ff4390 100644
--- a/security/selinux/include/classmap.h
+++ b/security/selinux/include/classmap.h
@@ -246,6 +246,8 @@ struct security_class_mapping secclass_map[] = {
NULL } },
{ "xdp_socket",
{ COMMON_SOCK_PERMS, NULL } },
+ { "mctp_socket",
+ { COMMON_SOCK_PERMS, NULL } },
{ "perf_event",
{ "open", "cpu", "kernel", "tracepoint", "read", "write", NULL } },
{ "lockdown",
@@ -255,6 +257,6 @@ struct security_class_mapping secclass_map[] = {
{ NULL }
};
-#if PF_MAX > 45
+#if PF_MAX > 46
#error New address family defined, please update secclass_map.
#endif
--
2.30.2
^ permalink raw reply related [flat|nested] 23+ messages in thread
* [PATCH net-next v4 02/15] mctp: Add base socket/protocol definitions
2021-07-29 2:20 [PATCH net-next v4 00/15] Add Management Component Transport Protocol support Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 01/15] mctp: Add MCTP base Jeremy Kerr
@ 2021-07-29 2:20 ` Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 03/15] mctp: Add base packet definitions Jeremy Kerr
` (13 subsequent siblings)
15 siblings, 0 replies; 23+ messages in thread
From: Jeremy Kerr @ 2021-07-29 2:20 UTC (permalink / raw)
To: netdev; +Cc: Matt Johnston, Andrew Jeffery, Jakub Kicinski, David S. Miller
Add an empty socket implementation, plus initialisation/destruction
handlers.
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
---
v2:
- Controller -> component
---
net/mctp/af_mctp.c | 163 +++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 163 insertions(+)
diff --git a/net/mctp/af_mctp.c b/net/mctp/af_mctp.c
index 8f9c77e97357..b3aeca6486e3 100644
--- a/net/mctp/af_mctp.c
+++ b/net/mctp/af_mctp.c
@@ -6,8 +6,171 @@
* Copyright (c) 2021 Google
*/
+#include <linux/net.h>
+#include <linux/mctp.h>
#include <linux/module.h>
+#include <linux/socket.h>
+
+#include <net/sock.h>
+
+struct mctp_sock {
+ struct sock sk;
+};
+
+static int mctp_release(struct socket *sock)
+{
+ struct sock *sk = sock->sk;
+
+ if (sk) {
+ sock->sk = NULL;
+ sk->sk_prot->close(sk, 0);
+ }
+
+ return 0;
+}
+
+static int mctp_bind(struct socket *sock, struct sockaddr *addr, int addrlen)
+{
+ return 0;
+}
+
+static int mctp_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
+{
+ return 0;
+}
+
+static int mctp_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
+ int flags)
+{
+ return 0;
+}
+
+static int mctp_setsockopt(struct socket *sock, int level, int optname,
+ sockptr_t optval, unsigned int optlen)
+{
+ return -EINVAL;
+}
+
+static int mctp_getsockopt(struct socket *sock, int level, int optname,
+ char __user *optval, int __user *optlen)
+{
+ return -EINVAL;
+}
+
+static const struct proto_ops mctp_dgram_ops = {
+ .family = PF_MCTP,
+ .release = mctp_release,
+ .bind = mctp_bind,
+ .connect = sock_no_connect,
+ .socketpair = sock_no_socketpair,
+ .accept = sock_no_accept,
+ .getname = sock_no_getname,
+ .poll = datagram_poll,
+ .ioctl = sock_no_ioctl,
+ .gettstamp = sock_gettstamp,
+ .listen = sock_no_listen,
+ .shutdown = sock_no_shutdown,
+ .setsockopt = mctp_setsockopt,
+ .getsockopt = mctp_getsockopt,
+ .sendmsg = mctp_sendmsg,
+ .recvmsg = mctp_recvmsg,
+ .mmap = sock_no_mmap,
+ .sendpage = sock_no_sendpage,
+};
+
+static void mctp_sk_close(struct sock *sk, long timeout)
+{
+ sk_common_release(sk);
+}
+
+static struct proto mctp_proto = {
+ .name = "MCTP",
+ .owner = THIS_MODULE,
+ .obj_size = sizeof(struct mctp_sock),
+ .close = mctp_sk_close,
+};
+
+static int mctp_pf_create(struct net *net, struct socket *sock,
+ int protocol, int kern)
+{
+ const struct proto_ops *ops;
+ struct proto *proto;
+ struct sock *sk;
+ int rc;
+
+ if (protocol)
+ return -EPROTONOSUPPORT;
+
+ /* only datagram sockets are supported */
+ if (sock->type != SOCK_DGRAM)
+ return -ESOCKTNOSUPPORT;
+
+ proto = &mctp_proto;
+ ops = &mctp_dgram_ops;
+
+ sock->state = SS_UNCONNECTED;
+ sock->ops = ops;
+
+ sk = sk_alloc(net, PF_MCTP, GFP_KERNEL, proto, kern);
+ if (!sk)
+ return -ENOMEM;
+
+ sock_init_data(sock, sk);
+
+ rc = 0;
+ if (sk->sk_prot->init)
+ rc = sk->sk_prot->init(sk);
+
+ if (rc)
+ goto err_sk_put;
+
+ return 0;
+
+err_sk_put:
+ sock_orphan(sk);
+ sock_put(sk);
+ return rc;
+}
+
+static struct net_proto_family mctp_pf = {
+ .family = PF_MCTP,
+ .create = mctp_pf_create,
+ .owner = THIS_MODULE,
+};
+
+static __init int mctp_init(void)
+{
+ int rc;
+
+ pr_info("mctp: management component transport protocol core\n");
+
+ rc = sock_register(&mctp_pf);
+ if (rc)
+ return rc;
+
+ rc = proto_register(&mctp_proto, 0);
+ if (rc)
+ goto err_unreg_sock;
+
+ return 0;
+
+err_unreg_sock:
+ sock_unregister(PF_MCTP);
+
+ return rc;
+}
+
+static __exit void mctp_exit(void)
+{
+ proto_unregister(&mctp_proto);
+ sock_unregister(PF_MCTP);
+}
+
+module_init(mctp_init);
+module_exit(mctp_exit);
MODULE_DESCRIPTION("MCTP core");
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Jeremy Kerr <jk@codeconstruct.com.au>");
+
+MODULE_ALIAS_NETPROTO(PF_MCTP);
--
2.30.2
^ permalink raw reply related [flat|nested] 23+ messages in thread
* [PATCH net-next v4 03/15] mctp: Add base packet definitions
2021-07-29 2:20 [PATCH net-next v4 00/15] Add Management Component Transport Protocol support Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 01/15] mctp: Add MCTP base Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 02/15] mctp: Add base socket/protocol definitions Jeremy Kerr
@ 2021-07-29 2:20 ` Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 04/15] mctp: Add sockaddr_mctp to uapi Jeremy Kerr
` (12 subsequent siblings)
15 siblings, 0 replies; 23+ messages in thread
From: Jeremy Kerr @ 2021-07-29 2:20 UTC (permalink / raw)
To: netdev; +Cc: Matt Johnston, Andrew Jeffery, Jakub Kicinski, David S. Miller
Simple packet header format as defined by DMTF DSP0236.
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
---
v2:
- Controller -> component
---
MAINTAINERS | 1 +
include/net/mctp.h | 35 +++++++++++++++++++++++++++++++++++
2 files changed, 36 insertions(+)
create mode 100644 include/net/mctp.h
diff --git a/MAINTAINERS b/MAINTAINERS
index 22a1ff9afd9d..770b986d10f0 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11037,6 +11037,7 @@ M: Jeremy Kerr <jk@codeconstruct.com.au>
M: Matt Johnston <matt@codeconstruct.com.au>
L: netdev@vger.kernel.org
S: Maintained
+F: include/net/mctp.h
F: net/mctp/
MAN-PAGES: MANUAL PAGES FOR LINUX -- Sections 2, 3, 4, 5, and 7
diff --git a/include/net/mctp.h b/include/net/mctp.h
new file mode 100644
index 000000000000..4c01e083be45
--- /dev/null
+++ b/include/net/mctp.h
@@ -0,0 +1,35 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Management Component Transport Protocol (MCTP)
+ *
+ * Copyright (c) 2021 Code Construct
+ * Copyright (c) 2021 Google
+ */
+
+#ifndef __NET_MCTP_H
+#define __NET_MCTP_H
+
+#include <linux/bits.h>
+
+/* MCTP packet definitions */
+struct mctp_hdr {
+ u8 ver;
+ u8 dest;
+ u8 src;
+ u8 flags_seq_tag;
+};
+
+#define MCTP_VER_MIN 1
+#define MCTP_VER_MAX 1
+
+/* Definitions for flags_seq_tag field */
+#define MCTP_HDR_FLAG_SOM BIT(7)
+#define MCTP_HDR_FLAG_EOM BIT(6)
+#define MCTP_HDR_FLAG_TO BIT(3)
+#define MCTP_HDR_FLAGS GENMASK(5, 3)
+#define MCTP_HDR_SEQ_SHIFT 4
+#define MCTP_HDR_SEQ_MASK GENMASK(1, 0)
+#define MCTP_HDR_TAG_SHIFT 0
+#define MCTP_HDR_TAG_MASK GENMASK(2, 0)
+
+#endif /* __NET_MCTP_H */
--
2.30.2
^ permalink raw reply related [flat|nested] 23+ messages in thread
* [PATCH net-next v4 04/15] mctp: Add sockaddr_mctp to uapi
2021-07-29 2:20 [PATCH net-next v4 00/15] Add Management Component Transport Protocol support Jeremy Kerr
` (2 preceding siblings ...)
2021-07-29 2:20 ` [PATCH net-next v4 03/15] mctp: Add base packet definitions Jeremy Kerr
@ 2021-07-29 2:20 ` Jeremy Kerr
2021-10-14 18:34 ` Eugene Syromiatnikov
2021-10-15 17:00 ` Eugene Syromiatnikov
2021-07-29 2:20 ` [PATCH net-next v4 05/15] mctp: Add initial driver infrastructure Jeremy Kerr
` (11 subsequent siblings)
15 siblings, 2 replies; 23+ messages in thread
From: Jeremy Kerr @ 2021-07-29 2:20 UTC (permalink / raw)
To: netdev; +Cc: Matt Johnston, Andrew Jeffery, Jakub Kicinski, David S. Miller
This change introduces the user-visible MCTP header, containing the
protocol-specific addressing definitions.
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
---
v2:
- include MCTP_ADDR_NULL and MCTP_TAG_* definitions
v3:
- don't use GENMASK/BIT in uapi
---
include/uapi/linux/mctp.h | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)
diff --git a/include/uapi/linux/mctp.h b/include/uapi/linux/mctp.h
index 2640a589c14c..52b54d13f385 100644
--- a/include/uapi/linux/mctp.h
+++ b/include/uapi/linux/mctp.h
@@ -9,7 +9,28 @@
#ifndef __UAPI_MCTP_H
#define __UAPI_MCTP_H
+#include <linux/types.h>
+
+typedef __u8 mctp_eid_t;
+
+struct mctp_addr {
+ mctp_eid_t s_addr;
+};
+
struct sockaddr_mctp {
+ unsigned short int smctp_family;
+ int smctp_network;
+ struct mctp_addr smctp_addr;
+ __u8 smctp_type;
+ __u8 smctp_tag;
};
+#define MCTP_NET_ANY 0x0
+
+#define MCTP_ADDR_NULL 0x00
+#define MCTP_ADDR_ANY 0xff
+
+#define MCTP_TAG_MASK 0x07
+#define MCTP_TAG_OWNER 0x08
+
#endif /* __UAPI_MCTP_H */
--
2.30.2
^ permalink raw reply related [flat|nested] 23+ messages in thread
* [PATCH net-next v4 05/15] mctp: Add initial driver infrastructure
2021-07-29 2:20 [PATCH net-next v4 00/15] Add Management Component Transport Protocol support Jeremy Kerr
` (3 preceding siblings ...)
2021-07-29 2:20 ` [PATCH net-next v4 04/15] mctp: Add sockaddr_mctp to uapi Jeremy Kerr
@ 2021-07-29 2:20 ` Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 06/15] mctp: Add device handling and netlink interface Jeremy Kerr
` (10 subsequent siblings)
15 siblings, 0 replies; 23+ messages in thread
From: Jeremy Kerr @ 2021-07-29 2:20 UTC (permalink / raw)
To: netdev; +Cc: Matt Johnston, Andrew Jeffery, Jakub Kicinski, David S. Miller
Add an empty drivers/net/mctp/, for future interface drivers.
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
---
MAINTAINERS | 1 +
drivers/net/Kconfig | 2 ++
drivers/net/Makefile | 1 +
drivers/net/mctp/Kconfig | 8 ++++++++
drivers/net/mctp/Makefile | 0
include/uapi/linux/if_arp.h | 1 +
6 files changed, 13 insertions(+)
create mode 100644 drivers/net/mctp/Kconfig
create mode 100644 drivers/net/mctp/Makefile
diff --git a/MAINTAINERS b/MAINTAINERS
index 770b986d10f0..e95eb3b00cd2 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11037,6 +11037,7 @@ M: Jeremy Kerr <jk@codeconstruct.com.au>
M: Matt Johnston <matt@codeconstruct.com.au>
L: netdev@vger.kernel.org
S: Maintained
+F: drivers/net/mctp/
F: include/net/mctp.h
F: net/mctp/
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 6977f8248df7..56213a8a1ec5 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -483,6 +483,8 @@ config NET_SB1000
source "drivers/net/phy/Kconfig"
+source "drivers/net/mctp/Kconfig"
+
source "drivers/net/mdio/Kconfig"
source "drivers/net/pcs/Kconfig"
diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index 7ffd2d03efaf..a48a664605a3 100644
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -69,6 +69,7 @@ obj-$(CONFIG_WAN) += wan/
obj-$(CONFIG_WLAN) += wireless/
obj-$(CONFIG_IEEE802154) += ieee802154/
obj-$(CONFIG_WWAN) += wwan/
+obj-$(CONFIG_MCTP) += mctp/
obj-$(CONFIG_VMXNET3) += vmxnet3/
obj-$(CONFIG_XEN_NETDEV_FRONTEND) += xen-netfront.o
diff --git a/drivers/net/mctp/Kconfig b/drivers/net/mctp/Kconfig
new file mode 100644
index 000000000000..d8f966cedc89
--- /dev/null
+++ b/drivers/net/mctp/Kconfig
@@ -0,0 +1,8 @@
+
+if MCTP
+
+menu "MCTP Device Drivers"
+
+endmenu
+
+endif
diff --git a/drivers/net/mctp/Makefile b/drivers/net/mctp/Makefile
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/include/uapi/linux/if_arp.h b/include/uapi/linux/if_arp.h
index c3cc5a9e5eaf..4783af9fe520 100644
--- a/include/uapi/linux/if_arp.h
+++ b/include/uapi/linux/if_arp.h
@@ -54,6 +54,7 @@
#define ARPHRD_X25 271 /* CCITT X.25 */
#define ARPHRD_HWX25 272 /* Boards with X.25 in firmware */
#define ARPHRD_CAN 280 /* Controller Area Network */
+#define ARPHRD_MCTP 290
#define ARPHRD_PPP 512
#define ARPHRD_CISCO 513 /* Cisco HDLC */
#define ARPHRD_HDLC ARPHRD_CISCO
--
2.30.2
^ permalink raw reply related [flat|nested] 23+ messages in thread
* [PATCH net-next v4 06/15] mctp: Add device handling and netlink interface
2021-07-29 2:20 [PATCH net-next v4 00/15] Add Management Component Transport Protocol support Jeremy Kerr
` (4 preceding siblings ...)
2021-07-29 2:20 ` [PATCH net-next v4 05/15] mctp: Add initial driver infrastructure Jeremy Kerr
@ 2021-07-29 2:20 ` Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 07/15] mctp: Add initial routing framework Jeremy Kerr
` (9 subsequent siblings)
15 siblings, 0 replies; 23+ messages in thread
From: Jeremy Kerr @ 2021-07-29 2:20 UTC (permalink / raw)
To: netdev; +Cc: Matt Johnston, Andrew Jeffery, Jakub Kicinski, David S. Miller
This change adds the infrastructure for managing MCTP netdevices; we add
a pointer to the AF_MCTP-specific data to struct netdevice, and hook up
the rtnetlink operations for adding and removing addresses.
Includes changes from Matt Johnston <matt@codeconstruct.com.au>.
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
---
v2:
- controller -> component
v3:
- fix addrinfo dump iteration & error path
- fix non-negative ERR_PTR
- use an array for local EIDs
- remove unnecessary RTM_GETLINK unregister
- add RTM_DELADDR
v4:
- upstream change: set_link_af no longer called with RTNL held
- add kdoc for net_device.mctp_ptr
---
MAINTAINERS | 1 +
include/linux/netdevice.h | 4 +
include/net/mctp.h | 14 ++
include/net/mctpdevice.h | 35 +++
include/uapi/linux/if_ether.h | 3 +
include/uapi/linux/if_link.h | 10 +
include/uapi/linux/mctp.h | 1 +
net/mctp/Makefile | 2 +-
net/mctp/af_mctp.c | 8 +
net/mctp/device.c | 414 ++++++++++++++++++++++++++++++++++
10 files changed, 491 insertions(+), 1 deletion(-)
create mode 100644 include/net/mctpdevice.h
create mode 100644 net/mctp/device.c
diff --git a/MAINTAINERS b/MAINTAINERS
index e95eb3b00cd2..c2943c227ee6 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11039,6 +11039,7 @@ L: netdev@vger.kernel.org
S: Maintained
F: drivers/net/mctp/
F: include/net/mctp.h
+F: include/net/mctpdevice.h
F: net/mctp/
MAN-PAGES: MANUAL PAGES FOR LINUX -- Sections 2, 3, 4, 5, and 7
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 226bbee06730..d63a94ecbf3b 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1823,6 +1823,7 @@ enum netdev_ml_priv_type {
* @ieee802154_ptr: IEEE 802.15.4 low-rate Wireless Personal Area Network
* device struct
* @mpls_ptr: mpls_dev struct pointer
+ * @mctp_ptr: MCTP specific data
*
* @dev_addr: Hw address (before bcast,
* because most packets are unicast)
@@ -2110,6 +2111,9 @@ struct net_device {
#if IS_ENABLED(CONFIG_MPLS_ROUTING)
struct mpls_dev __rcu *mpls_ptr;
#endif
+#if IS_ENABLED(CONFIG_MCTP)
+ struct mctp_dev __rcu *mctp_ptr;
+#endif
/*
* Cache lines mostly used on receive path (including eth_type_trans())
diff --git a/include/net/mctp.h b/include/net/mctp.h
index 4c01e083be45..61452e03aa85 100644
--- a/include/net/mctp.h
+++ b/include/net/mctp.h
@@ -10,6 +10,7 @@
#define __NET_MCTP_H
#include <linux/bits.h>
+#include <linux/mctp.h>
/* MCTP packet definitions */
struct mctp_hdr {
@@ -32,4 +33,17 @@ struct mctp_hdr {
#define MCTP_HDR_TAG_SHIFT 0
#define MCTP_HDR_TAG_MASK GENMASK(2, 0)
+static inline bool mctp_address_ok(mctp_eid_t eid)
+{
+ return eid >= 8 && eid < 255;
+}
+
+static inline struct mctp_hdr *mctp_hdr(struct sk_buff *skb)
+{
+ return (struct mctp_hdr *)skb_network_header(skb);
+}
+
+void mctp_device_init(void);
+void mctp_device_exit(void);
+
#endif /* __NET_MCTP_H */
diff --git a/include/net/mctpdevice.h b/include/net/mctpdevice.h
new file mode 100644
index 000000000000..71a11012fac7
--- /dev/null
+++ b/include/net/mctpdevice.h
@@ -0,0 +1,35 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Management Component Transport Protocol (MCTP) - device
+ * definitions.
+ *
+ * Copyright (c) 2021 Code Construct
+ * Copyright (c) 2021 Google
+ */
+
+#ifndef __NET_MCTPDEVICE_H
+#define __NET_MCTPDEVICE_H
+
+#include <linux/list.h>
+#include <linux/types.h>
+#include <linux/refcount.h>
+
+struct mctp_dev {
+ struct net_device *dev;
+
+ unsigned int net;
+
+ /* Only modified under RTNL. Reads have addrs_lock held */
+ u8 *addrs;
+ size_t num_addrs;
+ spinlock_t addrs_lock;
+
+ struct rcu_head rcu;
+};
+
+#define MCTP_INITIAL_DEFAULT_NET 1
+
+struct mctp_dev *mctp_dev_get_rtnl(const struct net_device *dev);
+struct mctp_dev *__mctp_dev_get(const struct net_device *dev);
+
+#endif /* __NET_MCTPDEVICE_H */
diff --git a/include/uapi/linux/if_ether.h b/include/uapi/linux/if_ether.h
index a0b637911d3c..5f589c7a8382 100644
--- a/include/uapi/linux/if_ether.h
+++ b/include/uapi/linux/if_ether.h
@@ -151,6 +151,9 @@
#define ETH_P_MAP 0x00F9 /* Qualcomm multiplexing and
* aggregation protocol
*/
+#define ETH_P_MCTP 0x00FA /* Management component transport
+ * protocol packets
+ */
/*
* This is an Ethernet frame header.
diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index 4882e81514b6..49b22afab78f 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -1260,4 +1260,14 @@ struct ifla_rmnet_flags {
__u32 mask;
};
+/* MCTP section */
+
+enum {
+ IFLA_MCTP_UNSPEC,
+ IFLA_MCTP_NET,
+ __IFLA_MCTP_MAX,
+};
+
+#define IFLA_MCTP_MAX (__IFLA_MCTP_MAX - 1)
+
#endif /* _UAPI_LINUX_IF_LINK_H */
diff --git a/include/uapi/linux/mctp.h b/include/uapi/linux/mctp.h
index 52b54d13f385..a9d8edb3402b 100644
--- a/include/uapi/linux/mctp.h
+++ b/include/uapi/linux/mctp.h
@@ -26,6 +26,7 @@ struct sockaddr_mctp {
};
#define MCTP_NET_ANY 0x0
+#define MCTP_NET_DEFAULT 0x0
#define MCTP_ADDR_NULL 0x00
#define MCTP_ADDR_ANY 0xff
diff --git a/net/mctp/Makefile b/net/mctp/Makefile
index 7c056b1b7939..2ea98c27b262 100644
--- a/net/mctp/Makefile
+++ b/net/mctp/Makefile
@@ -1,3 +1,3 @@
# SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_MCTP) += mctp.o
-mctp-objs := af_mctp.o
+mctp-objs := af_mctp.o device.o
diff --git a/net/mctp/af_mctp.c b/net/mctp/af_mctp.c
index b3aeca6486e3..401b4fa141a5 100644
--- a/net/mctp/af_mctp.c
+++ b/net/mctp/af_mctp.c
@@ -6,13 +6,18 @@
* Copyright (c) 2021 Google
*/
+#include <linux/if_arp.h>
#include <linux/net.h>
#include <linux/mctp.h>
#include <linux/module.h>
#include <linux/socket.h>
+#include <net/mctp.h>
+#include <net/mctpdevice.h>
#include <net/sock.h>
+/* socket implementation */
+
struct mctp_sock {
struct sock sk;
};
@@ -152,6 +157,8 @@ static __init int mctp_init(void)
if (rc)
goto err_unreg_sock;
+ mctp_device_init();
+
return 0;
err_unreg_sock:
@@ -162,6 +169,7 @@ static __init int mctp_init(void)
static __exit void mctp_exit(void)
{
+ mctp_device_exit();
proto_unregister(&mctp_proto);
sock_unregister(PF_MCTP);
}
diff --git a/net/mctp/device.c b/net/mctp/device.c
new file mode 100644
index 000000000000..877abe5312cd
--- /dev/null
+++ b/net/mctp/device.c
@@ -0,0 +1,414 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Management Component Transport Protocol (MCTP) - device implementation.
+ *
+ * Copyright (c) 2021 Code Construct
+ * Copyright (c) 2021 Google
+ */
+
+#include <linux/if_link.h>
+#include <linux/mctp.h>
+#include <linux/netdevice.h>
+#include <linux/rcupdate.h>
+#include <linux/rtnetlink.h>
+
+#include <net/addrconf.h>
+#include <net/netlink.h>
+#include <net/mctp.h>
+#include <net/mctpdevice.h>
+#include <net/sock.h>
+
+struct mctp_dump_cb {
+ int h;
+ int idx;
+ size_t a_idx;
+};
+
+/* unlocked: caller must hold rcu_read_lock */
+struct mctp_dev *__mctp_dev_get(const struct net_device *dev)
+{
+ return rcu_dereference(dev->mctp_ptr);
+}
+
+struct mctp_dev *mctp_dev_get_rtnl(const struct net_device *dev)
+{
+ return rtnl_dereference(dev->mctp_ptr);
+}
+
+static void mctp_dev_destroy(struct mctp_dev *mdev)
+{
+ struct net_device *dev = mdev->dev;
+
+ dev_put(dev);
+ kfree_rcu(mdev, rcu);
+}
+
+static int mctp_fill_addrinfo(struct sk_buff *skb, struct netlink_callback *cb,
+ struct mctp_dev *mdev, mctp_eid_t eid)
+{
+ struct ifaddrmsg *hdr;
+ struct nlmsghdr *nlh;
+
+ nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
+ RTM_NEWADDR, sizeof(*hdr), NLM_F_MULTI);
+ if (!nlh)
+ return -EMSGSIZE;
+
+ hdr = nlmsg_data(nlh);
+ hdr->ifa_family = AF_MCTP;
+ hdr->ifa_prefixlen = 0;
+ hdr->ifa_flags = 0;
+ hdr->ifa_scope = 0;
+ hdr->ifa_index = mdev->dev->ifindex;
+
+ if (nla_put_u8(skb, IFA_LOCAL, eid))
+ goto cancel;
+
+ if (nla_put_u8(skb, IFA_ADDRESS, eid))
+ goto cancel;
+
+ nlmsg_end(skb, nlh);
+
+ return 0;
+
+cancel:
+ nlmsg_cancel(skb, nlh);
+ return -EMSGSIZE;
+}
+
+static int mctp_dump_dev_addrinfo(struct mctp_dev *mdev, struct sk_buff *skb,
+ struct netlink_callback *cb)
+{
+ struct mctp_dump_cb *mcb = (void *)cb->ctx;
+ int rc = 0;
+
+ for (; mcb->a_idx < mdev->num_addrs; mcb->a_idx++) {
+ rc = mctp_fill_addrinfo(skb, cb, mdev, mdev->addrs[mcb->a_idx]);
+ if (rc < 0)
+ break;
+ }
+
+ return rc;
+}
+
+static int mctp_dump_addrinfo(struct sk_buff *skb, struct netlink_callback *cb)
+{
+ struct mctp_dump_cb *mcb = (void *)cb->ctx;
+ struct net *net = sock_net(skb->sk);
+ struct hlist_head *head;
+ struct net_device *dev;
+ struct ifaddrmsg *hdr;
+ struct mctp_dev *mdev;
+ int ifindex;
+ int idx, rc;
+
+ hdr = nlmsg_data(cb->nlh);
+ // filter by ifindex if requested
+ ifindex = hdr->ifa_index;
+
+ rcu_read_lock();
+ for (; mcb->h < NETDEV_HASHENTRIES; mcb->h++, mcb->idx = 0) {
+ idx = 0;
+ head = &net->dev_index_head[mcb->h];
+ hlist_for_each_entry_rcu(dev, head, index_hlist) {
+ if (idx >= mcb->idx &&
+ (ifindex == 0 || ifindex == dev->ifindex)) {
+ mdev = __mctp_dev_get(dev);
+ if (mdev) {
+ rc = mctp_dump_dev_addrinfo(mdev,
+ skb, cb);
+ // Error indicates full buffer, this
+ // callback will get retried.
+ if (rc < 0)
+ goto out;
+ }
+ }
+ idx++;
+ // reset for next iteration
+ mcb->a_idx = 0;
+ }
+ }
+out:
+ rcu_read_unlock();
+ mcb->idx = idx;
+
+ return skb->len;
+}
+
+static const struct nla_policy ifa_mctp_policy[IFA_MAX + 1] = {
+ [IFA_ADDRESS] = { .type = NLA_U8 },
+ [IFA_LOCAL] = { .type = NLA_U8 },
+};
+
+static int mctp_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct netlink_ext_ack *extack)
+{
+ struct net *net = sock_net(skb->sk);
+ struct nlattr *tb[IFA_MAX + 1];
+ struct net_device *dev;
+ struct mctp_addr *addr;
+ struct mctp_dev *mdev;
+ struct ifaddrmsg *ifm;
+ unsigned long flags;
+ u8 *tmp_addrs;
+ int rc;
+
+ rc = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_mctp_policy,
+ extack);
+ if (rc < 0)
+ return rc;
+
+ ifm = nlmsg_data(nlh);
+
+ if (tb[IFA_LOCAL])
+ addr = nla_data(tb[IFA_LOCAL]);
+ else if (tb[IFA_ADDRESS])
+ addr = nla_data(tb[IFA_ADDRESS]);
+ else
+ return -EINVAL;
+
+ /* find device */
+ dev = __dev_get_by_index(net, ifm->ifa_index);
+ if (!dev)
+ return -ENODEV;
+
+ mdev = mctp_dev_get_rtnl(dev);
+ if (!mdev)
+ return -ENODEV;
+
+ if (!mctp_address_ok(addr->s_addr))
+ return -EINVAL;
+
+ /* Prevent duplicates. Under RTNL so don't need to lock for reading */
+ if (memchr(mdev->addrs, addr->s_addr, mdev->num_addrs))
+ return -EEXIST;
+
+ tmp_addrs = kmalloc(mdev->num_addrs + 1, GFP_KERNEL);
+ if (!tmp_addrs)
+ return -ENOMEM;
+ memcpy(tmp_addrs, mdev->addrs, mdev->num_addrs);
+ tmp_addrs[mdev->num_addrs] = addr->s_addr;
+
+ /* Lock to write */
+ spin_lock_irqsave(&mdev->addrs_lock, flags);
+ mdev->num_addrs++;
+ swap(mdev->addrs, tmp_addrs);
+ spin_unlock_irqrestore(&mdev->addrs_lock, flags);
+
+ kfree(tmp_addrs);
+
+ return 0;
+}
+
+static int mctp_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct netlink_ext_ack *extack)
+{
+ struct net *net = sock_net(skb->sk);
+ struct nlattr *tb[IFA_MAX + 1];
+ struct net_device *dev;
+ struct mctp_addr *addr;
+ struct mctp_dev *mdev;
+ struct ifaddrmsg *ifm;
+ unsigned long flags;
+ u8 *pos;
+ int rc;
+
+ rc = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_mctp_policy,
+ extack);
+ if (rc < 0)
+ return rc;
+
+ ifm = nlmsg_data(nlh);
+
+ if (tb[IFA_LOCAL])
+ addr = nla_data(tb[IFA_LOCAL]);
+ else if (tb[IFA_ADDRESS])
+ addr = nla_data(tb[IFA_ADDRESS]);
+ else
+ return -EINVAL;
+
+ /* find device */
+ dev = __dev_get_by_index(net, ifm->ifa_index);
+ if (!dev)
+ return -ENODEV;
+
+ mdev = mctp_dev_get_rtnl(dev);
+ if (!mdev)
+ return -ENODEV;
+
+ pos = memchr(mdev->addrs, addr->s_addr, mdev->num_addrs);
+ if (!pos)
+ return -ENOENT;
+
+ spin_lock_irqsave(&mdev->addrs_lock, flags);
+ memmove(pos, pos + 1, mdev->num_addrs - 1 - (pos - mdev->addrs));
+ mdev->num_addrs--;
+ spin_unlock_irqrestore(&mdev->addrs_lock, flags);
+
+ return 0;
+}
+
+static struct mctp_dev *mctp_add_dev(struct net_device *dev)
+{
+ struct mctp_dev *mdev;
+
+ ASSERT_RTNL();
+
+ mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
+ if (!mdev)
+ return ERR_PTR(-ENOMEM);
+
+ spin_lock_init(&mdev->addrs_lock);
+
+ mdev->net = MCTP_INITIAL_DEFAULT_NET;
+
+ /* associate to net_device */
+ rcu_assign_pointer(dev->mctp_ptr, mdev);
+ dev_hold(dev);
+ mdev->dev = dev;
+
+ return mdev;
+}
+
+static int mctp_fill_link_af(struct sk_buff *skb,
+ const struct net_device *dev, u32 ext_filter_mask)
+{
+ struct mctp_dev *mdev;
+
+ mdev = mctp_dev_get_rtnl(dev);
+ if (!mdev)
+ return -ENODATA;
+ if (nla_put_u32(skb, IFLA_MCTP_NET, mdev->net))
+ return -EMSGSIZE;
+ return 0;
+}
+
+static size_t mctp_get_link_af_size(const struct net_device *dev,
+ u32 ext_filter_mask)
+{
+ struct mctp_dev *mdev;
+ unsigned int ret;
+
+ /* caller holds RCU */
+ mdev = __mctp_dev_get(dev);
+ if (!mdev)
+ return 0;
+ ret = nla_total_size(4); /* IFLA_MCTP_NET */
+ return ret;
+}
+
+static const struct nla_policy ifla_af_mctp_policy[IFLA_MCTP_MAX + 1] = {
+ [IFLA_MCTP_NET] = { .type = NLA_U32 },
+};
+
+static int mctp_set_link_af(struct net_device *dev, const struct nlattr *attr,
+ struct netlink_ext_ack *extack)
+{
+ struct nlattr *tb[IFLA_MCTP_MAX + 1];
+ struct mctp_dev *mdev;
+ int rc;
+
+ rc = nla_parse_nested(tb, IFLA_MCTP_MAX, attr, ifla_af_mctp_policy,
+ NULL);
+ if (rc)
+ return rc;
+
+ mdev = mctp_dev_get_rtnl(dev);
+ if (!mdev)
+ return 0;
+
+ if (tb[IFLA_MCTP_NET])
+ WRITE_ONCE(mdev->net, nla_get_u32(tb[IFLA_MCTP_NET]));
+
+ return 0;
+}
+
+static void mctp_unregister(struct net_device *dev)
+{
+ struct mctp_dev *mdev;
+
+ mdev = mctp_dev_get_rtnl(dev);
+
+ if (!mdev)
+ return;
+
+ RCU_INIT_POINTER(mdev->dev->mctp_ptr, NULL);
+
+ kfree(mdev->addrs);
+
+ mctp_dev_destroy(mdev);
+}
+
+static int mctp_register(struct net_device *dev)
+{
+ struct mctp_dev *mdev;
+
+ /* Already registered? */
+ if (rtnl_dereference(dev->mctp_ptr))
+ return 0;
+
+ /* only register specific types; MCTP-specific and loopback for now */
+ if (dev->type != ARPHRD_MCTP && dev->type != ARPHRD_LOOPBACK)
+ return 0;
+
+ mdev = mctp_add_dev(dev);
+ if (IS_ERR(mdev))
+ return PTR_ERR(mdev);
+
+ return 0;
+}
+
+static int mctp_dev_notify(struct notifier_block *this, unsigned long event,
+ void *ptr)
+{
+ struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+ int rc;
+
+ switch (event) {
+ case NETDEV_REGISTER:
+ rc = mctp_register(dev);
+ if (rc)
+ return notifier_from_errno(rc);
+ break;
+ case NETDEV_UNREGISTER:
+ mctp_unregister(dev);
+ break;
+ }
+
+ return NOTIFY_OK;
+}
+
+static struct rtnl_af_ops mctp_af_ops = {
+ .family = AF_MCTP,
+ .fill_link_af = mctp_fill_link_af,
+ .get_link_af_size = mctp_get_link_af_size,
+ .set_link_af = mctp_set_link_af,
+};
+
+static struct notifier_block mctp_dev_nb = {
+ .notifier_call = mctp_dev_notify,
+ .priority = ADDRCONF_NOTIFY_PRIORITY,
+};
+
+void __init mctp_device_init(void)
+{
+ register_netdevice_notifier(&mctp_dev_nb);
+
+ rtnl_register_module(THIS_MODULE, PF_MCTP, RTM_GETADDR,
+ NULL, mctp_dump_addrinfo, 0);
+ rtnl_register_module(THIS_MODULE, PF_MCTP, RTM_NEWADDR,
+ mctp_rtm_newaddr, NULL, 0);
+ rtnl_register_module(THIS_MODULE, PF_MCTP, RTM_DELADDR,
+ mctp_rtm_deladdr, NULL, 0);
+ rtnl_af_register(&mctp_af_ops);
+}
+
+void __exit mctp_device_exit(void)
+{
+ rtnl_af_unregister(&mctp_af_ops);
+ rtnl_unregister(PF_MCTP, RTM_DELADDR);
+ rtnl_unregister(PF_MCTP, RTM_NEWADDR);
+ rtnl_unregister(PF_MCTP, RTM_GETADDR);
+
+ unregister_netdevice_notifier(&mctp_dev_nb);
+}
--
2.30.2
^ permalink raw reply related [flat|nested] 23+ messages in thread
* [PATCH net-next v4 07/15] mctp: Add initial routing framework
2021-07-29 2:20 [PATCH net-next v4 00/15] Add Management Component Transport Protocol support Jeremy Kerr
` (5 preceding siblings ...)
2021-07-29 2:20 ` [PATCH net-next v4 06/15] mctp: Add device handling and netlink interface Jeremy Kerr
@ 2021-07-29 2:20 ` Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 08/15] mctp: Add netlink route management Jeremy Kerr
` (8 subsequent siblings)
15 siblings, 0 replies; 23+ messages in thread
From: Jeremy Kerr @ 2021-07-29 2:20 UTC (permalink / raw)
To: netdev; +Cc: Matt Johnston, Andrew Jeffery, Jakub Kicinski, David S. Miller
Add a simple routing table, and a couple of route output handlers, and
the mctp packet_type & handler.
Includes changes from Matt Johnston <matt@codeconstruct.com.au>.
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
---
v2:
- Controller -> component
v3:
- use an array for local EIDs
v4:
- don't inline mctp_rt_match_eid
---
MAINTAINERS | 1 +
include/net/mctp.h | 75 ++++++++
include/net/net_namespace.h | 4 +
include/net/netns/mctp.h | 16 ++
net/mctp/Makefile | 2 +-
net/mctp/af_mctp.c | 7 +
net/mctp/device.c | 8 +
net/mctp/route.c | 329 ++++++++++++++++++++++++++++++++++++
8 files changed, 441 insertions(+), 1 deletion(-)
create mode 100644 include/net/netns/mctp.h
create mode 100644 net/mctp/route.c
diff --git a/MAINTAINERS b/MAINTAINERS
index c2943c227ee6..4ca73465e690 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11040,6 +11040,7 @@ S: Maintained
F: drivers/net/mctp/
F: include/net/mctp.h
F: include/net/mctpdevice.h
+F: include/net/netns/mctp.h
F: net/mctp/
MAN-PAGES: MANUAL PAGES FOR LINUX -- Sections 2, 3, 4, 5, and 7
diff --git a/include/net/mctp.h b/include/net/mctp.h
index 61452e03aa85..4094bec5e5db 100644
--- a/include/net/mctp.h
+++ b/include/net/mctp.h
@@ -11,6 +11,7 @@
#include <linux/bits.h>
#include <linux/mctp.h>
+#include <net/net_namespace.h>
/* MCTP packet definitions */
struct mctp_hdr {
@@ -33,6 +34,8 @@ struct mctp_hdr {
#define MCTP_HDR_TAG_SHIFT 0
#define MCTP_HDR_TAG_MASK GENMASK(2, 0)
+#define MCTP_HEADER_MAXLEN 4
+
static inline bool mctp_address_ok(mctp_eid_t eid)
{
return eid >= 8 && eid < 255;
@@ -43,6 +46,78 @@ static inline struct mctp_hdr *mctp_hdr(struct sk_buff *skb)
return (struct mctp_hdr *)skb_network_header(skb);
}
+struct mctp_skb_cb {
+ unsigned int magic;
+ unsigned int net;
+ mctp_eid_t src;
+};
+
+/* skb control-block accessors with a little extra debugging for initial
+ * development.
+ *
+ * TODO: remove checks & mctp_skb_cb->magic; replace callers of __mctp_cb
+ * with mctp_cb().
+ *
+ * __mctp_cb() is only for the initial ingress code; we should see ->magic set
+ * at all times after this.
+ */
+static inline struct mctp_skb_cb *__mctp_cb(struct sk_buff *skb)
+{
+ struct mctp_skb_cb *cb = (void *)skb->cb;
+
+ cb->magic = 0x4d435450;
+ return cb;
+}
+
+static inline struct mctp_skb_cb *mctp_cb(struct sk_buff *skb)
+{
+ struct mctp_skb_cb *cb = (void *)skb->cb;
+
+ WARN_ON(cb->magic != 0x4d435450);
+ return (void *)(skb->cb);
+}
+
+/* Route definition.
+ *
+ * These are held in the pernet->mctp.routes list, with RCU protection for
+ * removed routes. We hold a reference to the netdev; routes need to be
+ * dropped on NETDEV_UNREGISTER events.
+ *
+ * Updates to the route table are performed under rtnl; all reads under RCU,
+ * so routes cannot be referenced over a RCU grace period. Specifically: A
+ * caller cannot block between mctp_route_lookup and passing the route to
+ * mctp_do_route.
+ */
+struct mctp_route {
+ mctp_eid_t min, max;
+
+ struct mctp_dev *dev;
+ unsigned int mtu;
+ int (*output)(struct mctp_route *route,
+ struct sk_buff *skb);
+
+ struct list_head list;
+ refcount_t refs;
+ struct rcu_head rcu;
+};
+
+/* route interfaces */
+struct mctp_route *mctp_route_lookup(struct net *net, unsigned int dnet,
+ mctp_eid_t daddr);
+
+int mctp_do_route(struct mctp_route *rt, struct sk_buff *skb);
+
+int mctp_local_output(struct sock *sk, struct mctp_route *rt,
+ struct sk_buff *skb, mctp_eid_t daddr, u8 req_tag);
+
+/* routing <--> device interface */
+int mctp_route_add_local(struct mctp_dev *mdev, mctp_eid_t addr);
+int mctp_route_remove_local(struct mctp_dev *mdev, mctp_eid_t addr);
+void mctp_route_remove_dev(struct mctp_dev *mdev);
+
+int mctp_routes_init(void);
+void mctp_routes_exit(void);
+
void mctp_device_init(void);
void mctp_device_exit(void);
diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h
index 12cf6d7ea62c..cc54750dd3db 100644
--- a/include/net/net_namespace.h
+++ b/include/net/net_namespace.h
@@ -34,6 +34,7 @@
#include <net/netns/xdp.h>
#include <net/netns/smc.h>
#include <net/netns/bpf.h>
+#include <net/netns/mctp.h>
#include <linux/ns_common.h>
#include <linux/idr.h>
#include <linux/skbuff.h>
@@ -167,6 +168,9 @@ struct net {
#ifdef CONFIG_XDP_SOCKETS
struct netns_xdp xdp;
#endif
+#if IS_ENABLED(CONFIG_MCTP)
+ struct netns_mctp mctp;
+#endif
#if IS_ENABLED(CONFIG_CRYPTO_USER)
struct sock *crypto_nlsk;
#endif
diff --git a/include/net/netns/mctp.h b/include/net/netns/mctp.h
new file mode 100644
index 000000000000..508459b08a59
--- /dev/null
+++ b/include/net/netns/mctp.h
@@ -0,0 +1,16 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * MCTP per-net structures
+ */
+
+#ifndef __NETNS_MCTP_H__
+#define __NETNS_MCTP_H__
+
+#include <linux/types.h>
+
+struct netns_mctp {
+ /* Only updated under RTNL, entries freed via RCU */
+ struct list_head routes;
+};
+
+#endif /* __NETNS_MCTP_H__ */
diff --git a/net/mctp/Makefile b/net/mctp/Makefile
index 2ea98c27b262..b1a330e9d82a 100644
--- a/net/mctp/Makefile
+++ b/net/mctp/Makefile
@@ -1,3 +1,3 @@
# SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_MCTP) += mctp.o
-mctp-objs := af_mctp.o device.o
+mctp-objs := af_mctp.o device.o route.o
diff --git a/net/mctp/af_mctp.c b/net/mctp/af_mctp.c
index 401b4fa141a5..8085f5912101 100644
--- a/net/mctp/af_mctp.c
+++ b/net/mctp/af_mctp.c
@@ -157,10 +157,16 @@ static __init int mctp_init(void)
if (rc)
goto err_unreg_sock;
+ rc = mctp_routes_init();
+ if (rc)
+ goto err_unreg_proto;
+
mctp_device_init();
return 0;
+err_unreg_proto:
+ proto_unregister(&mctp_proto);
err_unreg_sock:
sock_unregister(PF_MCTP);
@@ -170,6 +176,7 @@ static __init int mctp_init(void)
static __exit void mctp_exit(void)
{
mctp_device_exit();
+ mctp_routes_exit();
proto_unregister(&mctp_proto);
sock_unregister(PF_MCTP);
}
diff --git a/net/mctp/device.c b/net/mctp/device.c
index 877abe5312cd..5f1b18c17351 100644
--- a/net/mctp/device.c
+++ b/net/mctp/device.c
@@ -197,6 +197,8 @@ static int mctp_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
kfree(tmp_addrs);
+ mctp_route_add_local(mdev, addr->s_addr);
+
return 0;
}
@@ -240,6 +242,11 @@ static int mctp_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
if (!pos)
return -ENOENT;
+ rc = mctp_route_remove_local(mdev, addr->s_addr);
+ // we can ignore -ENOENT in the case a route was already removed
+ if (rc < 0 && rc != -ENOENT)
+ return rc;
+
spin_lock_irqsave(&mdev->addrs_lock, flags);
memmove(pos, pos + 1, mdev->num_addrs - 1 - (pos - mdev->addrs));
mdev->num_addrs--;
@@ -334,6 +341,7 @@ static void mctp_unregister(struct net_device *dev)
RCU_INIT_POINTER(mdev->dev->mctp_ptr, NULL);
+ mctp_route_remove_dev(mdev);
kfree(mdev->addrs);
mctp_dev_destroy(mdev);
diff --git a/net/mctp/route.c b/net/mctp/route.c
new file mode 100644
index 000000000000..2bcc13175a9e
--- /dev/null
+++ b/net/mctp/route.c
@@ -0,0 +1,329 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Management Component Transport Protocol (MCTP) - routing
+ * implementation.
+ *
+ * This is currently based on a simple routing table, with no dst cache. The
+ * number of routes should stay fairly small, so the lookup cost is small.
+ *
+ * Copyright (c) 2021 Code Construct
+ * Copyright (c) 2021 Google
+ */
+
+#include <linux/idr.h>
+#include <linux/mctp.h>
+#include <linux/netdevice.h>
+#include <linux/rtnetlink.h>
+#include <linux/skbuff.h>
+
+#include <uapi/linux/if_arp.h>
+
+#include <net/mctp.h>
+#include <net/mctpdevice.h>
+
+/* route output callbacks */
+static int mctp_route_discard(struct mctp_route *route, struct sk_buff *skb)
+{
+ kfree_skb(skb);
+ return 0;
+}
+
+static int mctp_route_input(struct mctp_route *route, struct sk_buff *skb)
+{
+ /* -> to local stack */
+ /* TODO: socket lookup, reassemble */
+ kfree_skb(skb);
+ return 0;
+}
+
+static int __always_unused mctp_route_output(struct mctp_route *route,
+ struct sk_buff *skb)
+{
+ unsigned int mtu;
+ int rc;
+
+ skb->protocol = htons(ETH_P_MCTP);
+
+ mtu = READ_ONCE(skb->dev->mtu);
+ if (skb->len > mtu) {
+ kfree_skb(skb);
+ return -EMSGSIZE;
+ }
+
+ /* TODO: daddr (from rt->neigh), saddr (from device?) */
+ rc = dev_hard_header(skb, skb->dev, ntohs(skb->protocol),
+ NULL, NULL, skb->len);
+ if (rc) {
+ kfree_skb(skb);
+ return -EHOSTUNREACH;
+ }
+
+ rc = dev_queue_xmit(skb);
+ if (rc)
+ rc = net_xmit_errno(rc);
+
+ return rc;
+}
+
+/* route alloc/release */
+static void mctp_route_release(struct mctp_route *rt)
+{
+ if (refcount_dec_and_test(&rt->refs)) {
+ dev_put(rt->dev->dev);
+ kfree_rcu(rt, rcu);
+ }
+}
+
+/* returns a route with the refcount at 1 */
+static struct mctp_route *mctp_route_alloc(void)
+{
+ struct mctp_route *rt;
+
+ rt = kzalloc(sizeof(*rt), GFP_KERNEL);
+ if (!rt)
+ return NULL;
+
+ INIT_LIST_HEAD(&rt->list);
+ refcount_set(&rt->refs, 1);
+ rt->output = mctp_route_discard;
+
+ return rt;
+}
+
+/* routing lookups */
+static bool mctp_rt_match_eid(struct mctp_route *rt,
+ unsigned int net, mctp_eid_t eid)
+{
+ return READ_ONCE(rt->dev->net) == net &&
+ rt->min <= eid && rt->max >= eid;
+}
+
+/* compares match, used for duplicate prevention */
+static bool mctp_rt_compare_exact(struct mctp_route *rt1,
+ struct mctp_route *rt2)
+{
+ ASSERT_RTNL();
+ return rt1->dev->net == rt2->dev->net &&
+ rt1->min == rt2->min &&
+ rt1->max == rt2->max;
+}
+
+struct mctp_route *mctp_route_lookup(struct net *net, unsigned int dnet,
+ mctp_eid_t daddr)
+{
+ struct mctp_route *tmp, *rt = NULL;
+
+ list_for_each_entry_rcu(tmp, &net->mctp.routes, list) {
+ /* TODO: add metrics */
+ if (mctp_rt_match_eid(tmp, dnet, daddr)) {
+ if (refcount_inc_not_zero(&tmp->refs)) {
+ rt = tmp;
+ break;
+ }
+ }
+ }
+
+ return rt;
+}
+
+/* sends a skb to rt and releases the route. */
+int mctp_do_route(struct mctp_route *rt, struct sk_buff *skb)
+{
+ int rc;
+
+ rc = rt->output(rt, skb);
+ mctp_route_release(rt);
+ return rc;
+}
+
+int mctp_local_output(struct sock *sk, struct mctp_route *rt,
+ struct sk_buff *skb, mctp_eid_t daddr, u8 req_tag)
+{
+ struct mctp_skb_cb *cb = mctp_cb(skb);
+ struct mctp_hdr *hdr;
+ unsigned long flags;
+ mctp_eid_t saddr;
+ int rc;
+
+ if (WARN_ON(!rt->dev))
+ return -EINVAL;
+
+ spin_lock_irqsave(&rt->dev->addrs_lock, flags);
+ if (rt->dev->num_addrs == 0) {
+ rc = -EHOSTUNREACH;
+ } else {
+ /* use the outbound interface's first address as our source */
+ saddr = rt->dev->addrs[0];
+ rc = 0;
+ }
+ spin_unlock_irqrestore(&rt->dev->addrs_lock, flags);
+
+ if (rc)
+ return rc;
+
+ /* TODO: we have the route MTU here; packetise */
+
+ skb_reset_transport_header(skb);
+ skb_push(skb, sizeof(struct mctp_hdr));
+ skb_reset_network_header(skb);
+ hdr = mctp_hdr(skb);
+ hdr->ver = 1;
+ hdr->dest = daddr;
+ hdr->src = saddr;
+ hdr->flags_seq_tag = MCTP_HDR_FLAG_SOM | MCTP_HDR_FLAG_EOM; /* TODO */
+
+ skb->protocol = htons(ETH_P_MCTP);
+ skb->priority = 0;
+
+ /* cb->net will have been set on initial ingress */
+ cb->src = saddr;
+
+ return mctp_do_route(rt, skb);
+}
+
+/* route management */
+int mctp_route_add_local(struct mctp_dev *mdev, mctp_eid_t addr)
+{
+ struct net *net = dev_net(mdev->dev);
+ struct mctp_route *rt, *ert;
+
+ rt = mctp_route_alloc();
+ if (!rt)
+ return -ENOMEM;
+
+ rt->min = addr;
+ rt->max = addr;
+ rt->dev = mdev;
+ dev_hold(rt->dev->dev);
+ rt->output = mctp_route_input;
+
+ ASSERT_RTNL();
+ /* Prevent duplicate identical routes. */
+ list_for_each_entry(ert, &net->mctp.routes, list) {
+ if (mctp_rt_compare_exact(rt, ert)) {
+ mctp_route_release(rt);
+ return -EEXIST;
+ }
+ }
+
+ list_add_rcu(&rt->list, &net->mctp.routes);
+
+ return 0;
+}
+
+int mctp_route_remove_local(struct mctp_dev *mdev, mctp_eid_t addr)
+{
+ struct net *net = dev_net(mdev->dev);
+ struct mctp_route *rt, *tmp;
+
+ ASSERT_RTNL();
+
+ list_for_each_entry_safe(rt, tmp, &net->mctp.routes, list) {
+ if (rt->dev == mdev && rt->min == addr && rt->max == addr) {
+ list_del_rcu(&rt->list);
+ /* TODO: immediate RTM_DELROUTE */
+ mctp_route_release(rt);
+ }
+ }
+
+ return 0;
+}
+
+/* removes all entries for a given device */
+void mctp_route_remove_dev(struct mctp_dev *mdev)
+{
+ struct net *net = dev_net(mdev->dev);
+ struct mctp_route *rt, *tmp;
+
+ ASSERT_RTNL();
+ list_for_each_entry_safe(rt, tmp, &net->mctp.routes, list) {
+ if (rt->dev == mdev) {
+ list_del_rcu(&rt->list);
+ /* TODO: immediate RTM_DELROUTE */
+ mctp_route_release(rt);
+ }
+ }
+}
+
+/* Incoming packet-handling */
+
+static int mctp_pkttype_receive(struct sk_buff *skb, struct net_device *dev,
+ struct packet_type *pt,
+ struct net_device *orig_dev)
+{
+ struct net *net = dev_net(dev);
+ struct mctp_skb_cb *cb;
+ struct mctp_route *rt;
+ struct mctp_hdr *mh;
+
+ /* basic non-data sanity checks */
+ if (dev->type != ARPHRD_MCTP)
+ goto err_drop;
+
+ if (!pskb_may_pull(skb, sizeof(struct mctp_hdr)))
+ goto err_drop;
+
+ skb_reset_transport_header(skb);
+ skb_reset_network_header(skb);
+
+ /* We have enough for a header; decode and route */
+ mh = mctp_hdr(skb);
+ if (mh->ver < MCTP_VER_MIN || mh->ver > MCTP_VER_MAX)
+ goto err_drop;
+
+ cb = __mctp_cb(skb);
+ rcu_read_lock();
+ cb->net = READ_ONCE(__mctp_dev_get(dev)->net);
+ rcu_read_unlock();
+
+ rt = mctp_route_lookup(net, cb->net, mh->dest);
+ if (!rt)
+ goto err_drop;
+
+ mctp_do_route(rt, skb);
+
+ return NET_RX_SUCCESS;
+
+err_drop:
+ kfree_skb(skb);
+ return NET_RX_DROP;
+}
+
+static struct packet_type mctp_packet_type = {
+ .type = cpu_to_be16(ETH_P_MCTP),
+ .func = mctp_pkttype_receive,
+};
+
+/* net namespace implementation */
+static int __net_init mctp_routes_net_init(struct net *net)
+{
+ struct netns_mctp *ns = &net->mctp;
+
+ INIT_LIST_HEAD(&ns->routes);
+ return 0;
+}
+
+static void __net_exit mctp_routes_net_exit(struct net *net)
+{
+ struct mctp_route *rt;
+
+ list_for_each_entry_rcu(rt, &net->mctp.routes, list)
+ mctp_route_release(rt);
+}
+
+static struct pernet_operations mctp_net_ops = {
+ .init = mctp_routes_net_init,
+ .exit = mctp_routes_net_exit,
+};
+
+int __init mctp_routes_init(void)
+{
+ dev_add_pack(&mctp_packet_type);
+ return register_pernet_subsys(&mctp_net_ops);
+}
+
+void __exit mctp_routes_exit(void)
+{
+ unregister_pernet_subsys(&mctp_net_ops);
+ dev_remove_pack(&mctp_packet_type);
+}
--
2.30.2
^ permalink raw reply related [flat|nested] 23+ messages in thread
* [PATCH net-next v4 08/15] mctp: Add netlink route management
2021-07-29 2:20 [PATCH net-next v4 00/15] Add Management Component Transport Protocol support Jeremy Kerr
` (6 preceding siblings ...)
2021-07-29 2:20 ` [PATCH net-next v4 07/15] mctp: Add initial routing framework Jeremy Kerr
@ 2021-07-29 2:20 ` Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 09/15] mctp: Add neighbour implementation Jeremy Kerr
` (7 subsequent siblings)
15 siblings, 0 replies; 23+ messages in thread
From: Jeremy Kerr @ 2021-07-29 2:20 UTC (permalink / raw)
To: netdev; +Cc: Matt Johnston, Andrew Jeffery, Jakub Kicinski, David S. Miller
From: Matt Johnston <matt@codeconstruct.com.au>
This change adds RTM_GETROUTE, RTM_NEWROUTE & RTM_DELROUTE handlers,
allowing management of the MCTP route table.
Includes changes from Jeremy Kerr <jk@codeconstruct.com.au>.
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
---
v4:
- require rtm_type == RTN_UNICAST in route management handlers
- remove unused RTAX policy table
---
include/net/mctp.h | 2 +
net/mctp/route.c | 258 +++++++++++++++++++++++++++++++++++++++++++--
2 files changed, 251 insertions(+), 9 deletions(-)
diff --git a/include/net/mctp.h b/include/net/mctp.h
index 4094bec5e5db..bc36e37e8198 100644
--- a/include/net/mctp.h
+++ b/include/net/mctp.h
@@ -111,6 +111,8 @@ int mctp_local_output(struct sock *sk, struct mctp_route *rt,
struct sk_buff *skb, mctp_eid_t daddr, u8 req_tag);
/* routing <--> device interface */
+unsigned int mctp_default_net(struct net *net);
+int mctp_default_net_set(struct net *net, unsigned int index);
int mctp_route_add_local(struct mctp_dev *mdev, mctp_eid_t addr);
int mctp_route_remove_local(struct mctp_dev *mdev, mctp_eid_t addr);
void mctp_route_remove_dev(struct mctp_dev *mdev);
diff --git a/net/mctp/route.c b/net/mctp/route.c
index 2bcc13175a9e..31568203f9d0 100644
--- a/net/mctp/route.c
+++ b/net/mctp/route.c
@@ -20,6 +20,8 @@
#include <net/mctp.h>
#include <net/mctpdevice.h>
+#include <net/netlink.h>
+#include <net/sock.h>
/* route output callbacks */
static int mctp_route_discard(struct mctp_route *route, struct sk_buff *skb)
@@ -36,8 +38,7 @@ static int mctp_route_input(struct mctp_route *route, struct sk_buff *skb)
return 0;
}
-static int __always_unused mctp_route_output(struct mctp_route *route,
- struct sk_buff *skb)
+static int mctp_route_output(struct mctp_route *route, struct sk_buff *skb)
{
unsigned int mtu;
int rc;
@@ -182,20 +183,29 @@ int mctp_local_output(struct sock *sk, struct mctp_route *rt,
}
/* route management */
-int mctp_route_add_local(struct mctp_dev *mdev, mctp_eid_t addr)
+static int mctp_route_add(struct mctp_dev *mdev, mctp_eid_t daddr_start,
+ unsigned int daddr_extent, unsigned int mtu,
+ bool is_local)
{
struct net *net = dev_net(mdev->dev);
struct mctp_route *rt, *ert;
+ if (!mctp_address_ok(daddr_start))
+ return -EINVAL;
+
+ if (daddr_extent > 0xff || daddr_start + daddr_extent >= 255)
+ return -EINVAL;
+
rt = mctp_route_alloc();
if (!rt)
return -ENOMEM;
- rt->min = addr;
- rt->max = addr;
+ rt->min = daddr_start;
+ rt->max = daddr_start + daddr_extent;
+ rt->mtu = mtu;
rt->dev = mdev;
dev_hold(rt->dev->dev);
- rt->output = mctp_route_input;
+ rt->output = is_local ? mctp_route_input : mctp_route_output;
ASSERT_RTNL();
/* Prevent duplicate identical routes. */
@@ -211,22 +221,43 @@ int mctp_route_add_local(struct mctp_dev *mdev, mctp_eid_t addr)
return 0;
}
-int mctp_route_remove_local(struct mctp_dev *mdev, mctp_eid_t addr)
+static int mctp_route_remove(struct mctp_dev *mdev, mctp_eid_t daddr_start,
+ unsigned int daddr_extent)
{
struct net *net = dev_net(mdev->dev);
struct mctp_route *rt, *tmp;
+ mctp_eid_t daddr_end;
+ bool dropped;
+
+ if (daddr_extent > 0xff || daddr_start + daddr_extent >= 255)
+ return -EINVAL;
+
+ daddr_end = daddr_start + daddr_extent;
+ dropped = false;
ASSERT_RTNL();
list_for_each_entry_safe(rt, tmp, &net->mctp.routes, list) {
- if (rt->dev == mdev && rt->min == addr && rt->max == addr) {
+ if (rt->dev == mdev &&
+ rt->min == daddr_start && rt->max == daddr_end) {
list_del_rcu(&rt->list);
/* TODO: immediate RTM_DELROUTE */
mctp_route_release(rt);
+ dropped = true;
}
}
- return 0;
+ return dropped ? 0 : -ENOENT;
+}
+
+int mctp_route_add_local(struct mctp_dev *mdev, mctp_eid_t addr)
+{
+ return mctp_route_add(mdev, addr, 0, 0, true);
+}
+
+int mctp_route_remove_local(struct mctp_dev *mdev, mctp_eid_t addr)
+{
+ return mctp_route_remove(mdev, addr, 0);
}
/* removes all entries for a given device */
@@ -294,6 +325,204 @@ static struct packet_type mctp_packet_type = {
.func = mctp_pkttype_receive,
};
+/* netlink interface */
+
+static const struct nla_policy rta_mctp_policy[RTA_MAX + 1] = {
+ [RTA_DST] = { .type = NLA_U8 },
+ [RTA_METRICS] = { .type = NLA_NESTED },
+ [RTA_OIF] = { .type = NLA_U32 },
+};
+
+/* Common part for RTM_NEWROUTE and RTM_DELROUTE parsing.
+ * tb must hold RTA_MAX+1 elements.
+ */
+static int mctp_route_nlparse(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct netlink_ext_ack *extack,
+ struct nlattr **tb, struct rtmsg **rtm,
+ struct mctp_dev **mdev, mctp_eid_t *daddr_start)
+{
+ struct net *net = sock_net(skb->sk);
+ struct net_device *dev;
+ unsigned int ifindex;
+ int rc;
+
+ rc = nlmsg_parse(nlh, sizeof(struct rtmsg), tb, RTA_MAX,
+ rta_mctp_policy, extack);
+ if (rc < 0) {
+ NL_SET_ERR_MSG(extack, "incorrect format");
+ return rc;
+ }
+
+ if (!tb[RTA_DST]) {
+ NL_SET_ERR_MSG(extack, "dst EID missing");
+ return -EINVAL;
+ }
+ *daddr_start = nla_get_u8(tb[RTA_DST]);
+
+ if (!tb[RTA_OIF]) {
+ NL_SET_ERR_MSG(extack, "ifindex missing");
+ return -EINVAL;
+ }
+ ifindex = nla_get_u32(tb[RTA_OIF]);
+
+ *rtm = nlmsg_data(nlh);
+ if ((*rtm)->rtm_family != AF_MCTP) {
+ NL_SET_ERR_MSG(extack, "route family must be AF_MCTP");
+ return -EINVAL;
+ }
+
+ dev = __dev_get_by_index(net, ifindex);
+ if (!dev) {
+ NL_SET_ERR_MSG(extack, "bad ifindex");
+ return -ENODEV;
+ }
+ *mdev = mctp_dev_get_rtnl(dev);
+ if (!*mdev)
+ return -ENODEV;
+
+ if (dev->flags & IFF_LOOPBACK) {
+ NL_SET_ERR_MSG(extack, "no routes to loopback");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int mctp_newroute(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct netlink_ext_ack *extack)
+{
+ struct nlattr *tb[RTA_MAX + 1];
+ mctp_eid_t daddr_start;
+ struct mctp_dev *mdev;
+ struct rtmsg *rtm;
+ unsigned int mtu;
+ int rc;
+
+ rc = mctp_route_nlparse(skb, nlh, extack, tb,
+ &rtm, &mdev, &daddr_start);
+ if (rc < 0)
+ return rc;
+
+ if (rtm->rtm_type != RTN_UNICAST) {
+ NL_SET_ERR_MSG(extack, "rtm_type must be RTN_UNICAST");
+ return -EINVAL;
+ }
+
+ /* TODO: parse mtu from nlparse */
+ mtu = 0;
+
+ rc = mctp_route_add(mdev, daddr_start, rtm->rtm_dst_len, mtu, false);
+ return rc;
+}
+
+static int mctp_delroute(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct netlink_ext_ack *extack)
+{
+ struct nlattr *tb[RTA_MAX + 1];
+ mctp_eid_t daddr_start;
+ struct mctp_dev *mdev;
+ struct rtmsg *rtm;
+ int rc;
+
+ rc = mctp_route_nlparse(skb, nlh, extack, tb,
+ &rtm, &mdev, &daddr_start);
+ if (rc < 0)
+ return rc;
+
+ /* we only have unicast routes */
+ if (rtm->rtm_type != RTN_UNICAST)
+ return -EINVAL;
+
+ rc = mctp_route_remove(mdev, daddr_start, rtm->rtm_dst_len);
+ return rc;
+}
+
+static int mctp_fill_rtinfo(struct sk_buff *skb, struct mctp_route *rt,
+ u32 portid, u32 seq, int event, unsigned int flags)
+{
+ struct nlmsghdr *nlh;
+ struct rtmsg *hdr;
+ void *metrics;
+
+ nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
+ if (!nlh)
+ return -EMSGSIZE;
+
+ hdr = nlmsg_data(nlh);
+ hdr->rtm_family = AF_MCTP;
+
+ /* we use the _len fields as a number of EIDs, rather than
+ * a number of bits in the address
+ */
+ hdr->rtm_dst_len = rt->max - rt->min;
+ hdr->rtm_src_len = 0;
+ hdr->rtm_tos = 0;
+ hdr->rtm_table = RT_TABLE_DEFAULT;
+ hdr->rtm_protocol = RTPROT_STATIC; /* everything is user-defined */
+ hdr->rtm_scope = RT_SCOPE_LINK; /* TODO: scope in mctp_route? */
+ hdr->rtm_type = RTN_ANYCAST; /* TODO: type from route */
+
+ if (nla_put_u8(skb, RTA_DST, rt->min))
+ goto cancel;
+
+ metrics = nla_nest_start_noflag(skb, RTA_METRICS);
+ if (!metrics)
+ goto cancel;
+
+ if (rt->mtu) {
+ if (nla_put_u32(skb, RTAX_MTU, rt->mtu))
+ goto cancel;
+ }
+
+ nla_nest_end(skb, metrics);
+
+ if (rt->dev) {
+ if (nla_put_u32(skb, RTA_OIF, rt->dev->dev->ifindex))
+ goto cancel;
+ }
+
+ /* TODO: conditional neighbour physaddr? */
+
+ nlmsg_end(skb, nlh);
+
+ return 0;
+
+cancel:
+ nlmsg_cancel(skb, nlh);
+ return -EMSGSIZE;
+}
+
+static int mctp_dump_rtinfo(struct sk_buff *skb, struct netlink_callback *cb)
+{
+ struct net *net = sock_net(skb->sk);
+ struct mctp_route *rt;
+ int s_idx, idx;
+
+ /* TODO: allow filtering on route data, possibly under
+ * cb->strict_check
+ */
+
+ /* TODO: change to struct overlay */
+ s_idx = cb->args[0];
+ idx = 0;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(rt, &net->mctp.routes, list) {
+ if (idx++ < s_idx)
+ continue;
+ if (mctp_fill_rtinfo(skb, rt,
+ NETLINK_CB(cb->skb).portid,
+ cb->nlh->nlmsg_seq,
+ RTM_NEWROUTE, NLM_F_MULTI) < 0)
+ break;
+ }
+
+ rcu_read_unlock();
+ cb->args[0] = idx;
+
+ return skb->len;
+}
+
/* net namespace implementation */
static int __net_init mctp_routes_net_init(struct net *net)
{
@@ -319,11 +548,22 @@ static struct pernet_operations mctp_net_ops = {
int __init mctp_routes_init(void)
{
dev_add_pack(&mctp_packet_type);
+
+ rtnl_register_module(THIS_MODULE, PF_MCTP, RTM_GETROUTE,
+ NULL, mctp_dump_rtinfo, 0);
+ rtnl_register_module(THIS_MODULE, PF_MCTP, RTM_NEWROUTE,
+ mctp_newroute, NULL, 0);
+ rtnl_register_module(THIS_MODULE, PF_MCTP, RTM_DELROUTE,
+ mctp_delroute, NULL, 0);
+
return register_pernet_subsys(&mctp_net_ops);
}
void __exit mctp_routes_exit(void)
{
unregister_pernet_subsys(&mctp_net_ops);
+ rtnl_unregister(PF_MCTP, RTM_DELROUTE);
+ rtnl_unregister(PF_MCTP, RTM_NEWROUTE);
+ rtnl_unregister(PF_MCTP, RTM_GETROUTE);
dev_remove_pack(&mctp_packet_type);
}
--
2.30.2
^ permalink raw reply related [flat|nested] 23+ messages in thread
* [PATCH net-next v4 09/15] mctp: Add neighbour implementation
2021-07-29 2:20 [PATCH net-next v4 00/15] Add Management Component Transport Protocol support Jeremy Kerr
` (7 preceding siblings ...)
2021-07-29 2:20 ` [PATCH net-next v4 08/15] mctp: Add netlink route management Jeremy Kerr
@ 2021-07-29 2:20 ` Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 10/15] mctp: Add neighbour netlink interface Jeremy Kerr
` (6 subsequent siblings)
15 siblings, 0 replies; 23+ messages in thread
From: Jeremy Kerr @ 2021-07-29 2:20 UTC (permalink / raw)
To: netdev; +Cc: Matt Johnston, Andrew Jeffery, Jakub Kicinski, David S. Miller
From: Matt Johnston <matt@codeconstruct.com.au>
Add an initial neighbour table implementation, to be used in the route
output path.
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
---
v2:
- controller -> component
---
include/net/mctp.h | 25 +++++++
include/net/mctpdevice.h | 1 +
include/net/netns/mctp.h | 4 ++
net/mctp/Makefile | 2 +-
net/mctp/af_mctp.c | 5 ++
net/mctp/device.c | 1 +
net/mctp/neigh.c | 141 +++++++++++++++++++++++++++++++++++++++
7 files changed, 178 insertions(+), 1 deletion(-)
create mode 100644 net/mctp/neigh.c
diff --git a/include/net/mctp.h b/include/net/mctp.h
index bc36e37e8198..53f035c8b59c 100644
--- a/include/net/mctp.h
+++ b/include/net/mctp.h
@@ -117,6 +117,31 @@ int mctp_route_add_local(struct mctp_dev *mdev, mctp_eid_t addr);
int mctp_route_remove_local(struct mctp_dev *mdev, mctp_eid_t addr);
void mctp_route_remove_dev(struct mctp_dev *mdev);
+/* neighbour definitions */
+enum mctp_neigh_source {
+ MCTP_NEIGH_STATIC,
+ MCTP_NEIGH_DISCOVER,
+};
+
+struct mctp_neigh {
+ struct mctp_dev *dev;
+ mctp_eid_t eid;
+ enum mctp_neigh_source source;
+
+ unsigned char ha[MAX_ADDR_LEN];
+
+ struct list_head list;
+ struct rcu_head rcu;
+};
+
+int mctp_neigh_init(void);
+void mctp_neigh_exit(void);
+
+// ret_hwaddr may be NULL, otherwise must have space for MAX_ADDR_LEN
+int mctp_neigh_lookup(struct mctp_dev *dev, mctp_eid_t eid,
+ void *ret_hwaddr);
+void mctp_neigh_remove_dev(struct mctp_dev *mdev);
+
int mctp_routes_init(void);
void mctp_routes_exit(void);
diff --git a/include/net/mctpdevice.h b/include/net/mctpdevice.h
index 71a11012fac7..57e773ff08bb 100644
--- a/include/net/mctpdevice.h
+++ b/include/net/mctpdevice.h
@@ -31,5 +31,6 @@ struct mctp_dev {
struct mctp_dev *mctp_dev_get_rtnl(const struct net_device *dev);
struct mctp_dev *__mctp_dev_get(const struct net_device *dev);
+struct mctp_dev *mctp_dev_get_rtnl(const struct net_device *dev);
#endif /* __NET_MCTPDEVICE_H */
diff --git a/include/net/netns/mctp.h b/include/net/netns/mctp.h
index 508459b08a59..2f5ebeeb320e 100644
--- a/include/net/netns/mctp.h
+++ b/include/net/netns/mctp.h
@@ -11,6 +11,10 @@
struct netns_mctp {
/* Only updated under RTNL, entries freed via RCU */
struct list_head routes;
+
+ /* neighbour table */
+ struct mutex neigh_lock;
+ struct list_head neighbours;
};
#endif /* __NETNS_MCTP_H__ */
diff --git a/net/mctp/Makefile b/net/mctp/Makefile
index b1a330e9d82a..0171333384d7 100644
--- a/net/mctp/Makefile
+++ b/net/mctp/Makefile
@@ -1,3 +1,3 @@
# SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_MCTP) += mctp.o
-mctp-objs := af_mctp.o device.o route.o
+mctp-objs := af_mctp.o device.o route.o neigh.o
diff --git a/net/mctp/af_mctp.c b/net/mctp/af_mctp.c
index 8085f5912101..58701e6b282c 100644
--- a/net/mctp/af_mctp.c
+++ b/net/mctp/af_mctp.c
@@ -161,6 +161,10 @@ static __init int mctp_init(void)
if (rc)
goto err_unreg_proto;
+ rc = mctp_neigh_init();
+ if (rc)
+ goto err_unreg_proto;
+
mctp_device_init();
return 0;
@@ -176,6 +180,7 @@ static __init int mctp_init(void)
static __exit void mctp_exit(void)
{
mctp_device_exit();
+ mctp_neigh_exit();
mctp_routes_exit();
proto_unregister(&mctp_proto);
sock_unregister(PF_MCTP);
diff --git a/net/mctp/device.c b/net/mctp/device.c
index 5f1b18c17351..aa049590acda 100644
--- a/net/mctp/device.c
+++ b/net/mctp/device.c
@@ -342,6 +342,7 @@ static void mctp_unregister(struct net_device *dev)
RCU_INIT_POINTER(mdev->dev->mctp_ptr, NULL);
mctp_route_remove_dev(mdev);
+ mctp_neigh_remove_dev(mdev);
kfree(mdev->addrs);
mctp_dev_destroy(mdev);
diff --git a/net/mctp/neigh.c b/net/mctp/neigh.c
new file mode 100644
index 000000000000..8603f0c45a8f
--- /dev/null
+++ b/net/mctp/neigh.c
@@ -0,0 +1,141 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Management Component Transport Protocol (MCTP) - routing
+ * implementation.
+ *
+ * This is currently based on a simple routing table, with no dst cache. The
+ * number of routes should stay fairly small, so the lookup cost is small.
+ *
+ * Copyright (c) 2021 Code Construct
+ * Copyright (c) 2021 Google
+ */
+
+#include <linux/idr.h>
+#include <linux/mctp.h>
+#include <linux/netdevice.h>
+#include <linux/rtnetlink.h>
+#include <linux/skbuff.h>
+
+#include <net/mctp.h>
+#include <net/mctpdevice.h>
+#include <net/netlink.h>
+#include <net/sock.h>
+
+static int __always_unused mctp_neigh_add(struct mctp_dev *mdev, mctp_eid_t eid,
+ enum mctp_neigh_source source,
+ size_t lladdr_len, const void *lladdr)
+{
+ struct net *net = dev_net(mdev->dev);
+ struct mctp_neigh *neigh;
+ int rc;
+
+ mutex_lock(&net->mctp.neigh_lock);
+ if (mctp_neigh_lookup(mdev, eid, NULL) == 0) {
+ rc = -EEXIST;
+ goto out;
+ }
+
+ if (lladdr_len > sizeof(neigh->ha)) {
+ rc = -EINVAL;
+ goto out;
+ }
+
+ neigh = kzalloc(sizeof(*neigh), GFP_KERNEL);
+ if (!neigh) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ INIT_LIST_HEAD(&neigh->list);
+ neigh->dev = mdev;
+ dev_hold(neigh->dev->dev);
+ neigh->eid = eid;
+ neigh->source = source;
+ memcpy(neigh->ha, lladdr, lladdr_len);
+
+ list_add_rcu(&neigh->list, &net->mctp.neighbours);
+ rc = 0;
+out:
+ mutex_unlock(&net->mctp.neigh_lock);
+ return rc;
+}
+
+static void __mctp_neigh_free(struct rcu_head *rcu)
+{
+ struct mctp_neigh *neigh = container_of(rcu, struct mctp_neigh, rcu);
+
+ dev_put(neigh->dev->dev);
+ kfree(neigh);
+}
+
+/* Removes all neighbour entries referring to a device */
+void mctp_neigh_remove_dev(struct mctp_dev *mdev)
+{
+ struct net *net = dev_net(mdev->dev);
+ struct mctp_neigh *neigh, *tmp;
+
+ mutex_lock(&net->mctp.neigh_lock);
+ list_for_each_entry_safe(neigh, tmp, &net->mctp.neighbours, list) {
+ if (neigh->dev == mdev) {
+ list_del_rcu(&neigh->list);
+ /* TODO: immediate RTM_DELNEIGH */
+ call_rcu(&neigh->rcu, __mctp_neigh_free);
+ }
+ }
+
+ mutex_unlock(&net->mctp.neigh_lock);
+}
+
+int mctp_neigh_lookup(struct mctp_dev *mdev, mctp_eid_t eid, void *ret_hwaddr)
+{
+ struct net *net = dev_net(mdev->dev);
+ struct mctp_neigh *neigh;
+ int rc = -EHOSTUNREACH; // TODO: or ENOENT?
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(neigh, &net->mctp.neighbours, list) {
+ if (mdev == neigh->dev && eid == neigh->eid) {
+ if (ret_hwaddr)
+ memcpy(ret_hwaddr, neigh->ha,
+ sizeof(neigh->ha));
+ rc = 0;
+ break;
+ }
+ }
+ rcu_read_unlock();
+ return rc;
+}
+
+/* namespace registration */
+static int __net_init mctp_neigh_net_init(struct net *net)
+{
+ struct netns_mctp *ns = &net->mctp;
+
+ INIT_LIST_HEAD(&ns->neighbours);
+ return 0;
+}
+
+static void __net_exit mctp_neigh_net_exit(struct net *net)
+{
+ struct netns_mctp *ns = &net->mctp;
+ struct mctp_neigh *neigh;
+
+ list_for_each_entry(neigh, &ns->neighbours, list)
+ call_rcu(&neigh->rcu, __mctp_neigh_free);
+}
+
+/* net namespace implementation */
+
+static struct pernet_operations mctp_net_ops = {
+ .init = mctp_neigh_net_init,
+ .exit = mctp_neigh_net_exit,
+};
+
+int __init mctp_neigh_init(void)
+{
+ return register_pernet_subsys(&mctp_net_ops);
+}
+
+void __exit mctp_neigh_exit(void)
+{
+ unregister_pernet_subsys(&mctp_net_ops);
+}
--
2.30.2
^ permalink raw reply related [flat|nested] 23+ messages in thread
* [PATCH net-next v4 10/15] mctp: Add neighbour netlink interface
2021-07-29 2:20 [PATCH net-next v4 00/15] Add Management Component Transport Protocol support Jeremy Kerr
` (8 preceding siblings ...)
2021-07-29 2:20 ` [PATCH net-next v4 09/15] mctp: Add neighbour implementation Jeremy Kerr
@ 2021-07-29 2:20 ` Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 11/15] mctp: Populate socket implementation Jeremy Kerr
` (5 subsequent siblings)
15 siblings, 0 replies; 23+ messages in thread
From: Jeremy Kerr @ 2021-07-29 2:20 UTC (permalink / raw)
To: netdev; +Cc: Matt Johnston, Andrew Jeffery, Jakub Kicinski, David S. Miller
From: Matt Johnston <matt@codeconstruct.com.au>
This change adds the netlink interfaces for manipulating the MCTP
neighbour table.
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
---
net/mctp/neigh.c | 207 ++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 204 insertions(+), 3 deletions(-)
diff --git a/net/mctp/neigh.c b/net/mctp/neigh.c
index 8603f0c45a8f..90ed2f02d1fb 100644
--- a/net/mctp/neigh.c
+++ b/net/mctp/neigh.c
@@ -21,9 +21,9 @@
#include <net/netlink.h>
#include <net/sock.h>
-static int __always_unused mctp_neigh_add(struct mctp_dev *mdev, mctp_eid_t eid,
- enum mctp_neigh_source source,
- size_t lladdr_len, const void *lladdr)
+static int mctp_neigh_add(struct mctp_dev *mdev, mctp_eid_t eid,
+ enum mctp_neigh_source source,
+ size_t lladdr_len, const void *lladdr)
{
struct net *net = dev_net(mdev->dev);
struct mctp_neigh *neigh;
@@ -85,6 +85,196 @@ void mctp_neigh_remove_dev(struct mctp_dev *mdev)
mutex_unlock(&net->mctp.neigh_lock);
}
+// TODO: add a "source" flag so netlink can only delete static neighbours?
+static int mctp_neigh_remove(struct mctp_dev *mdev, mctp_eid_t eid)
+{
+ struct net *net = dev_net(mdev->dev);
+ struct mctp_neigh *neigh, *tmp;
+ bool dropped = false;
+
+ mutex_lock(&net->mctp.neigh_lock);
+ list_for_each_entry_safe(neigh, tmp, &net->mctp.neighbours, list) {
+ if (neigh->dev == mdev && neigh->eid == eid) {
+ list_del_rcu(&neigh->list);
+ /* TODO: immediate RTM_DELNEIGH */
+ call_rcu(&neigh->rcu, __mctp_neigh_free);
+ dropped = true;
+ }
+ }
+
+ mutex_unlock(&net->mctp.neigh_lock);
+ return dropped ? 0 : -ENOENT;
+}
+
+static const struct nla_policy nd_mctp_policy[NDA_MAX + 1] = {
+ [NDA_DST] = { .type = NLA_U8 },
+ [NDA_LLADDR] = { .type = NLA_BINARY, .len = MAX_ADDR_LEN },
+};
+
+static int mctp_rtm_newneigh(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct netlink_ext_ack *extack)
+{
+ struct net *net = sock_net(skb->sk);
+ struct net_device *dev;
+ struct mctp_dev *mdev;
+ struct ndmsg *ndm;
+ struct nlattr *tb[NDA_MAX + 1];
+ int rc;
+ mctp_eid_t eid;
+ void *lladdr;
+ int lladdr_len;
+
+ rc = nlmsg_parse(nlh, sizeof(*ndm), tb, NDA_MAX, nd_mctp_policy,
+ extack);
+ if (rc < 0) {
+ NL_SET_ERR_MSG(extack, "lladdr too large?");
+ return rc;
+ }
+
+ if (!tb[NDA_DST]) {
+ NL_SET_ERR_MSG(extack, "Neighbour EID must be specified");
+ return -EINVAL;
+ }
+
+ if (!tb[NDA_LLADDR]) {
+ NL_SET_ERR_MSG(extack, "Neighbour lladdr must be specified");
+ return -EINVAL;
+ }
+
+ eid = nla_get_u8(tb[NDA_DST]);
+ if (!mctp_address_ok(eid)) {
+ NL_SET_ERR_MSG(extack, "Invalid neighbour EID");
+ return -EINVAL;
+ }
+
+ lladdr = nla_data(tb[NDA_LLADDR]);
+ lladdr_len = nla_len(tb[NDA_LLADDR]);
+
+ ndm = nlmsg_data(nlh);
+
+ dev = __dev_get_by_index(net, ndm->ndm_ifindex);
+ if (!dev)
+ return -ENODEV;
+
+ mdev = mctp_dev_get_rtnl(dev);
+ if (!mdev)
+ return -ENODEV;
+
+ if (lladdr_len != dev->addr_len) {
+ NL_SET_ERR_MSG(extack, "Wrong lladdr length");
+ return -EINVAL;
+ }
+
+ return mctp_neigh_add(mdev, eid, MCTP_NEIGH_STATIC,
+ lladdr_len, lladdr);
+}
+
+static int mctp_rtm_delneigh(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct netlink_ext_ack *extack)
+{
+ struct net *net = sock_net(skb->sk);
+ struct nlattr *tb[NDA_MAX + 1];
+ struct net_device *dev;
+ struct mctp_dev *mdev;
+ struct ndmsg *ndm;
+ int rc;
+ mctp_eid_t eid;
+
+ rc = nlmsg_parse(nlh, sizeof(*ndm), tb, NDA_MAX, nd_mctp_policy,
+ extack);
+ if (rc < 0) {
+ NL_SET_ERR_MSG(extack, "incorrect format");
+ return rc;
+ }
+
+ if (!tb[NDA_DST]) {
+ NL_SET_ERR_MSG(extack, "Neighbour EID must be specified");
+ return -EINVAL;
+ }
+ eid = nla_get_u8(tb[NDA_DST]);
+
+ ndm = nlmsg_data(nlh);
+ dev = __dev_get_by_index(net, ndm->ndm_ifindex);
+ if (!dev)
+ return -ENODEV;
+
+ mdev = mctp_dev_get_rtnl(dev);
+ if (!mdev)
+ return -ENODEV;
+
+ return mctp_neigh_remove(mdev, eid);
+}
+
+static int mctp_fill_neigh(struct sk_buff *skb, u32 portid, u32 seq, int event,
+ unsigned int flags, struct mctp_neigh *neigh)
+{
+ struct net_device *dev = neigh->dev->dev;
+ struct nlmsghdr *nlh;
+ struct ndmsg *hdr;
+
+ nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
+ if (!nlh)
+ return -EMSGSIZE;
+
+ hdr = nlmsg_data(nlh);
+ hdr->ndm_family = AF_MCTP;
+ hdr->ndm_ifindex = dev->ifindex;
+ hdr->ndm_state = 0; // TODO other state bits?
+ if (neigh->source == MCTP_NEIGH_STATIC)
+ hdr->ndm_state |= NUD_PERMANENT;
+ hdr->ndm_flags = 0;
+ hdr->ndm_type = RTN_UNICAST; // TODO: is loopback RTN_LOCAL?
+
+ if (nla_put_u8(skb, NDA_DST, neigh->eid))
+ goto cancel;
+
+ if (nla_put(skb, NDA_LLADDR, dev->addr_len, neigh->ha))
+ goto cancel;
+
+ nlmsg_end(skb, nlh);
+
+ return 0;
+cancel:
+ nlmsg_cancel(skb, nlh);
+ return -EMSGSIZE;
+}
+
+static int mctp_rtm_getneigh(struct sk_buff *skb, struct netlink_callback *cb)
+{
+ struct net *net = sock_net(skb->sk);
+ int rc, idx, req_ifindex;
+ struct mctp_neigh *neigh;
+ struct ndmsg *ndmsg;
+ struct {
+ int idx;
+ } *cbctx = (void *)cb->ctx;
+
+ ndmsg = nlmsg_data(cb->nlh);
+ req_ifindex = ndmsg->ndm_ifindex;
+
+ idx = 0;
+ rcu_read_lock();
+ list_for_each_entry_rcu(neigh, &net->mctp.neighbours, list) {
+ if (idx < cbctx->idx)
+ goto cont;
+
+ rc = 0;
+ if (req_ifindex == 0 || req_ifindex == neigh->dev->dev->ifindex)
+ rc = mctp_fill_neigh(skb, NETLINK_CB(cb->skb).portid,
+ cb->nlh->nlmsg_seq,
+ RTM_NEWNEIGH, NLM_F_MULTI, neigh);
+
+ if (rc)
+ break;
+cont:
+ idx++;
+ }
+ rcu_read_unlock();
+
+ cbctx->idx = idx;
+ return skb->len;
+}
+
int mctp_neigh_lookup(struct mctp_dev *mdev, mctp_eid_t eid, void *ret_hwaddr)
{
struct net *net = dev_net(mdev->dev);
@@ -111,6 +301,7 @@ static int __net_init mctp_neigh_net_init(struct net *net)
struct netns_mctp *ns = &net->mctp;
INIT_LIST_HEAD(&ns->neighbours);
+ mutex_init(&ns->neigh_lock);
return 0;
}
@@ -132,10 +323,20 @@ static struct pernet_operations mctp_net_ops = {
int __init mctp_neigh_init(void)
{
+ rtnl_register_module(THIS_MODULE, PF_MCTP, RTM_NEWNEIGH,
+ mctp_rtm_newneigh, NULL, 0);
+ rtnl_register_module(THIS_MODULE, PF_MCTP, RTM_DELNEIGH,
+ mctp_rtm_delneigh, NULL, 0);
+ rtnl_register_module(THIS_MODULE, PF_MCTP, RTM_GETNEIGH,
+ NULL, mctp_rtm_getneigh, 0);
+
return register_pernet_subsys(&mctp_net_ops);
}
void __exit mctp_neigh_exit(void)
{
unregister_pernet_subsys(&mctp_net_ops);
+ rtnl_unregister(PF_MCTP, RTM_GETNEIGH);
+ rtnl_unregister(PF_MCTP, RTM_DELNEIGH);
+ rtnl_unregister(PF_MCTP, RTM_NEWNEIGH);
}
--
2.30.2
^ permalink raw reply related [flat|nested] 23+ messages in thread
* [PATCH net-next v4 11/15] mctp: Populate socket implementation
2021-07-29 2:20 [PATCH net-next v4 00/15] Add Management Component Transport Protocol support Jeremy Kerr
` (9 preceding siblings ...)
2021-07-29 2:20 ` [PATCH net-next v4 10/15] mctp: Add neighbour netlink interface Jeremy Kerr
@ 2021-07-29 2:20 ` Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 12/15] mctp: Implement message fragmentation & reassembly Jeremy Kerr
` (4 subsequent siblings)
15 siblings, 0 replies; 23+ messages in thread
From: Jeremy Kerr @ 2021-07-29 2:20 UTC (permalink / raw)
To: netdev; +Cc: Matt Johnston, Andrew Jeffery, Jakub Kicinski, David S. Miller
Start filling-out the socket syscalls: bind, sendmsg & recvmsg.
This requires an input route implementation, so we add to
mctp_route_input, allowing lookups on binds & message tags. This just
handles single-packet messages at present, we will add fragmentation in
a future change.
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
---
v2:
- require CAP_NET_BIND_SERVICE for bind(), CAP_NET_RAW for TX.
- be strict about sendmsg() tag bits
v3:
- fix comment typos
v4:
- fix mctp_sock->keys rcu annotations
---
include/net/mctp.h | 59 ++++++++++
include/net/netns/mctp.h | 13 +++
net/mctp/af_mctp.c | 203 +++++++++++++++++++++++++++++++++--
net/mctp/route.c | 226 ++++++++++++++++++++++++++++++++++++++-
4 files changed, 491 insertions(+), 10 deletions(-)
diff --git a/include/net/mctp.h b/include/net/mctp.h
index 53f035c8b59c..f2d98f6993c0 100644
--- a/include/net/mctp.h
+++ b/include/net/mctp.h
@@ -12,6 +12,7 @@
#include <linux/bits.h>
#include <linux/mctp.h>
#include <net/net_namespace.h>
+#include <net/sock.h>
/* MCTP packet definitions */
struct mctp_hdr {
@@ -46,6 +47,64 @@ static inline struct mctp_hdr *mctp_hdr(struct sk_buff *skb)
return (struct mctp_hdr *)skb_network_header(skb);
}
+/* socket implementation */
+struct mctp_sock {
+ struct sock sk;
+
+ /* bind() params */
+ int bind_net;
+ mctp_eid_t bind_addr;
+ __u8 bind_type;
+
+ /* list of mctp_sk_key, for incoming tag lookup. updates protected
+ * by sk->net->keys_lock
+ */
+ struct hlist_head keys;
+};
+
+/* Key for matching incoming packets to sockets or reassembly contexts.
+ * Packets are matched on (src,dest,tag).
+ *
+ * Lifetime requirements:
+ *
+ * - keys are free()ed via RCU
+ *
+ * - a mctp_sk_key contains a reference to a struct sock; this is valid
+ * for the life of the key. On sock destruction (through unhash), the key is
+ * removed from lists (see below), and will not be observable after a RCU
+ * grace period.
+ *
+ * any RX occurring within that grace period may still queue to the socket,
+ * but will hit the SOCK_DEAD case before the socket is freed.
+ *
+ * - these mctp_sk_keys appear on two lists:
+ * 1) the struct mctp_sock->keys list
+ * 2) the struct netns_mctp->keys list
+ *
+ * updates to either list are performed under the netns_mctp->keys
+ * lock.
+ *
+ * - there is a single destruction path for a mctp_sk_key - through socket
+ * unhash (see mctp_sk_unhash). This performs the list removal under
+ * keys_lock.
+ */
+struct mctp_sk_key {
+ mctp_eid_t peer_addr;
+ mctp_eid_t local_addr;
+ __u8 tag; /* incoming tag match; invert TO for local */
+
+ /* we hold a ref to sk when set */
+ struct sock *sk;
+
+ /* routing lookup list */
+ struct hlist_node hlist;
+
+ /* per-socket list */
+ struct hlist_node sklist;
+
+ struct rcu_head rcu;
+};
+
struct mctp_skb_cb {
unsigned int magic;
unsigned int net;
diff --git a/include/net/netns/mctp.h b/include/net/netns/mctp.h
index 2f5ebeeb320e..14ae6d37e52a 100644
--- a/include/net/netns/mctp.h
+++ b/include/net/netns/mctp.h
@@ -12,6 +12,19 @@ struct netns_mctp {
/* Only updated under RTNL, entries freed via RCU */
struct list_head routes;
+ /* Bound sockets: list of sockets bound by type.
+ * This list is updated from non-atomic contexts (under bind_lock),
+ * and read (under rcu) in packet rx
+ */
+ struct mutex bind_lock;
+ struct hlist_head binds;
+
+ /* tag allocations. This list is read and updated from atomic contexts,
+ * but elements are free()ed after a RCU grace-period
+ */
+ spinlock_t keys_lock;
+ struct hlist_head keys;
+
/* neighbour table */
struct mutex neigh_lock;
struct list_head neighbours;
diff --git a/net/mctp/af_mctp.c b/net/mctp/af_mctp.c
index 58701e6b282c..52bd7f2b78db 100644
--- a/net/mctp/af_mctp.c
+++ b/net/mctp/af_mctp.c
@@ -18,10 +18,6 @@
/* socket implementation */
-struct mctp_sock {
- struct sock sk;
-};
-
static int mctp_release(struct socket *sock)
{
struct sock *sk = sock->sk;
@@ -36,18 +32,160 @@ static int mctp_release(struct socket *sock)
static int mctp_bind(struct socket *sock, struct sockaddr *addr, int addrlen)
{
- return 0;
+ struct sock *sk = sock->sk;
+ struct mctp_sock *msk = container_of(sk, struct mctp_sock, sk);
+ struct sockaddr_mctp *smctp;
+ int rc;
+
+ if (addrlen < sizeof(*smctp))
+ return -EINVAL;
+
+ if (addr->sa_family != AF_MCTP)
+ return -EAFNOSUPPORT;
+
+ if (!capable(CAP_NET_BIND_SERVICE))
+ return -EACCES;
+
+ /* it's a valid sockaddr for MCTP, cast and do protocol checks */
+ smctp = (struct sockaddr_mctp *)addr;
+
+ lock_sock(sk);
+
+ /* TODO: allow rebind */
+ if (sk_hashed(sk)) {
+ rc = -EADDRINUSE;
+ goto out_release;
+ }
+ msk->bind_net = smctp->smctp_network;
+ msk->bind_addr = smctp->smctp_addr.s_addr;
+ msk->bind_type = smctp->smctp_type & 0x7f; /* ignore the IC bit */
+
+ rc = sk->sk_prot->hash(sk);
+
+out_release:
+ release_sock(sk);
+
+ return rc;
}
static int mctp_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
{
- return 0;
+ DECLARE_SOCKADDR(struct sockaddr_mctp *, addr, msg->msg_name);
+ const int hlen = MCTP_HEADER_MAXLEN + sizeof(struct mctp_hdr);
+ int rc, addrlen = msg->msg_namelen;
+ struct sock *sk = sock->sk;
+ struct mctp_skb_cb *cb;
+ struct mctp_route *rt;
+ struct sk_buff *skb;
+
+ if (addr) {
+ if (addrlen < sizeof(struct sockaddr_mctp))
+ return -EINVAL;
+ if (addr->smctp_family != AF_MCTP)
+ return -EINVAL;
+ if (addr->smctp_tag & ~(MCTP_TAG_MASK | MCTP_TAG_OWNER))
+ return -EINVAL;
+
+ } else {
+ /* TODO: connect()ed sockets */
+ return -EDESTADDRREQ;
+ }
+
+ if (!capable(CAP_NET_RAW))
+ return -EACCES;
+
+ rt = mctp_route_lookup(sock_net(sk), addr->smctp_network,
+ addr->smctp_addr.s_addr);
+ if (!rt)
+ return -EHOSTUNREACH;
+
+ skb = sock_alloc_send_skb(sk, hlen + 1 + len,
+ msg->msg_flags & MSG_DONTWAIT, &rc);
+ if (!skb)
+ return rc;
+
+ skb_reserve(skb, hlen);
+
+ /* set type as fist byte in payload */
+ *(u8 *)skb_put(skb, 1) = addr->smctp_type;
+
+ rc = memcpy_from_msg((void *)skb_put(skb, len), msg, len);
+ if (rc < 0) {
+ kfree_skb(skb);
+ return rc;
+ }
+
+ /* set up cb */
+ cb = __mctp_cb(skb);
+ cb->net = addr->smctp_network;
+
+ rc = mctp_local_output(sk, rt, skb, addr->smctp_addr.s_addr,
+ addr->smctp_tag);
+
+ return rc ? : len;
}
static int mctp_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
int flags)
{
- return 0;
+ DECLARE_SOCKADDR(struct sockaddr_mctp *, addr, msg->msg_name);
+ struct sock *sk = sock->sk;
+ struct sk_buff *skb;
+ size_t msglen;
+ u8 type;
+ int rc;
+
+ if (flags & ~(MSG_DONTWAIT | MSG_TRUNC | MSG_PEEK))
+ return -EOPNOTSUPP;
+
+ skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &rc);
+ if (!skb)
+ return rc;
+
+ if (!skb->len) {
+ rc = 0;
+ goto out_free;
+ }
+
+ /* extract message type, remove from data */
+ type = *((u8 *)skb->data);
+ msglen = skb->len - 1;
+
+ if (len < msglen)
+ msg->msg_flags |= MSG_TRUNC;
+ else
+ len = msglen;
+
+ rc = skb_copy_datagram_msg(skb, 1, msg, len);
+ if (rc < 0)
+ goto out_free;
+
+ sock_recv_ts_and_drops(msg, sk, skb);
+
+ if (addr) {
+ struct mctp_skb_cb *cb = mctp_cb(skb);
+ /* TODO: expand mctp_skb_cb for header fields? */
+ struct mctp_hdr *hdr = mctp_hdr(skb);
+
+ hdr = mctp_hdr(skb);
+ addr = msg->msg_name;
+ addr->smctp_family = AF_MCTP;
+ addr->smctp_network = cb->net;
+ addr->smctp_addr.s_addr = hdr->src;
+ addr->smctp_type = type;
+ addr->smctp_tag = hdr->flags_seq_tag &
+ (MCTP_HDR_TAG_MASK | MCTP_HDR_FLAG_TO);
+ msg->msg_namelen = sizeof(*addr);
+ }
+
+ rc = len;
+
+ if (flags & MSG_TRUNC)
+ rc = msglen;
+
+out_free:
+ skb_free_datagram(sk, skb);
+ return rc;
}
static int mctp_setsockopt(struct socket *sock, int level, int optname,
@@ -83,16 +221,63 @@ static const struct proto_ops mctp_dgram_ops = {
.sendpage = sock_no_sendpage,
};
+static int mctp_sk_init(struct sock *sk)
+{
+ struct mctp_sock *msk = container_of(sk, struct mctp_sock, sk);
+
+ INIT_HLIST_HEAD(&msk->keys);
+ return 0;
+}
+
static void mctp_sk_close(struct sock *sk, long timeout)
{
sk_common_release(sk);
}
+static int mctp_sk_hash(struct sock *sk)
+{
+ struct net *net = sock_net(sk);
+
+ mutex_lock(&net->mctp.bind_lock);
+ sk_add_node_rcu(sk, &net->mctp.binds);
+ mutex_unlock(&net->mctp.bind_lock);
+
+ return 0;
+}
+
+static void mctp_sk_unhash(struct sock *sk)
+{
+ struct mctp_sock *msk = container_of(sk, struct mctp_sock, sk);
+ struct net *net = sock_net(sk);
+ struct mctp_sk_key *key;
+ struct hlist_node *tmp;
+ unsigned long flags;
+
+ /* remove from any type-based binds */
+ mutex_lock(&net->mctp.bind_lock);
+ sk_del_node_init_rcu(sk);
+ mutex_unlock(&net->mctp.bind_lock);
+
+ /* remove tag allocations */
+ spin_lock_irqsave(&net->mctp.keys_lock, flags);
+ hlist_for_each_entry_safe(key, tmp, &msk->keys, sklist) {
+ hlist_del_rcu(&key->sklist);
+ hlist_del_rcu(&key->hlist);
+ kfree_rcu(key, rcu);
+ }
+ spin_unlock_irqrestore(&net->mctp.keys_lock, flags);
+
+ synchronize_rcu();
+}
+
static struct proto mctp_proto = {
.name = "MCTP",
.owner = THIS_MODULE,
.obj_size = sizeof(struct mctp_sock),
+ .init = mctp_sk_init,
.close = mctp_sk_close,
+ .hash = mctp_sk_hash,
+ .unhash = mctp_sk_unhash,
};
static int mctp_pf_create(struct net *net, struct socket *sock,
@@ -147,6 +332,10 @@ static __init int mctp_init(void)
{
int rc;
+ /* ensure our uapi tag definitions match the header format */
+ BUILD_BUG_ON(MCTP_TAG_OWNER != MCTP_HDR_FLAG_TO);
+ BUILD_BUG_ON(MCTP_TAG_MASK != MCTP_HDR_TAG_MASK);
+
pr_info("mctp: management component transport protocol core\n");
rc = sock_register(&mctp_pf);
diff --git a/net/mctp/route.c b/net/mctp/route.c
index 31568203f9d0..cc9891672eaa 100644
--- a/net/mctp/route.c
+++ b/net/mctp/route.c
@@ -30,10 +30,139 @@ static int mctp_route_discard(struct mctp_route *route, struct sk_buff *skb)
return 0;
}
+static struct mctp_sock *mctp_lookup_bind(struct net *net, struct sk_buff *skb)
+{
+ struct mctp_skb_cb *cb = mctp_cb(skb);
+ struct mctp_hdr *mh;
+ struct sock *sk;
+ u8 type;
+
+ WARN_ON(!rcu_read_lock_held());
+
+ /* TODO: look up in skb->cb? */
+ mh = mctp_hdr(skb);
+
+ if (!skb_headlen(skb))
+ return NULL;
+
+ type = (*(u8 *)skb->data) & 0x7f;
+
+ sk_for_each_rcu(sk, &net->mctp.binds) {
+ struct mctp_sock *msk = container_of(sk, struct mctp_sock, sk);
+
+ if (msk->bind_net != MCTP_NET_ANY && msk->bind_net != cb->net)
+ continue;
+
+ if (msk->bind_type != type)
+ continue;
+
+ if (msk->bind_addr != MCTP_ADDR_ANY &&
+ msk->bind_addr != mh->dest)
+ continue;
+
+ return msk;
+ }
+
+ return NULL;
+}
+
+static bool mctp_key_match(struct mctp_sk_key *key, mctp_eid_t local,
+ mctp_eid_t peer, u8 tag)
+{
+ if (key->local_addr != local)
+ return false;
+
+ if (key->peer_addr != peer)
+ return false;
+
+ if (key->tag != tag)
+ return false;
+
+ return true;
+}
+
+static struct mctp_sk_key *mctp_lookup_key(struct net *net, struct sk_buff *skb,
+ mctp_eid_t peer)
+{
+ struct mctp_sk_key *key, *ret;
+ struct mctp_hdr *mh;
+ u8 tag;
+
+ WARN_ON(!rcu_read_lock_held());
+
+ mh = mctp_hdr(skb);
+ tag = mh->flags_seq_tag & (MCTP_HDR_TAG_MASK | MCTP_HDR_FLAG_TO);
+
+ ret = NULL;
+
+ hlist_for_each_entry_rcu(key, &net->mctp.keys, hlist) {
+ if (mctp_key_match(key, mh->dest, peer, tag)) {
+ ret = key;
+ break;
+ }
+ }
+
+ return ret;
+}
+
static int mctp_route_input(struct mctp_route *route, struct sk_buff *skb)
{
- /* -> to local stack */
- /* TODO: socket lookup, reassemble */
+ struct net *net = dev_net(skb->dev);
+ struct mctp_sk_key *key;
+ struct mctp_sock *msk;
+ struct mctp_hdr *mh;
+
+ msk = NULL;
+
+ /* we may be receiving a locally-routed packet; drop source sk
+ * accounting
+ */
+ skb_orphan(skb);
+
+ /* ensure we have enough data for a header and a type */
+ if (skb->len < sizeof(struct mctp_hdr) + 1)
+ goto drop;
+
+ /* grab header, advance data ptr */
+ mh = mctp_hdr(skb);
+ skb_pull(skb, sizeof(struct mctp_hdr));
+
+ if (mh->ver != 1)
+ goto drop;
+
+ /* TODO: reassembly */
+ if ((mh->flags_seq_tag & (MCTP_HDR_FLAG_SOM | MCTP_HDR_FLAG_EOM))
+ != (MCTP_HDR_FLAG_SOM | MCTP_HDR_FLAG_EOM))
+ goto drop;
+
+ rcu_read_lock();
+ /* 1. lookup socket matching (src,dest,tag) */
+ key = mctp_lookup_key(net, skb, mh->src);
+
+ /* 2. lookup socket macthing (BCAST,dest,tag) */
+ if (!key)
+ key = mctp_lookup_key(net, skb, MCTP_ADDR_ANY);
+
+ /* 3. SOM? -> lookup bound socket, conditionally (!EOM) create
+ * mapping for future (1)/(2).
+ */
+ if (key)
+ msk = container_of(key->sk, struct mctp_sock, sk);
+ else if (!msk && (mh->flags_seq_tag & MCTP_HDR_FLAG_SOM))
+ msk = mctp_lookup_bind(net, skb);
+
+ if (!msk)
+ goto unlock_drop;
+
+ sock_queue_rcv_skb(&msk->sk, skb);
+
+ rcu_read_unlock();
+
+ return 0;
+
+unlock_drop:
+ rcu_read_unlock();
+drop:
kfree_skb(skb);
return 0;
}
@@ -91,6 +220,80 @@ static struct mctp_route *mctp_route_alloc(void)
return rt;
}
+/* tag management */
+static void mctp_reserve_tag(struct net *net, struct mctp_sk_key *key,
+ struct mctp_sock *msk)
+{
+ struct netns_mctp *mns = &net->mctp;
+
+ lockdep_assert_held(&mns->keys_lock);
+
+ key->sk = &msk->sk;
+
+ /* we hold the net->key_lock here, allowing updates to both
+ * then net and sk
+ */
+ hlist_add_head_rcu(&key->hlist, &mns->keys);
+ hlist_add_head_rcu(&key->sklist, &msk->keys);
+}
+
+/* Allocate a locally-owned tag value for (saddr, daddr), and reserve
+ * it for the socket msk
+ */
+static int mctp_alloc_local_tag(struct mctp_sock *msk,
+ mctp_eid_t saddr, mctp_eid_t daddr, u8 *tagp)
+{
+ struct net *net = sock_net(&msk->sk);
+ struct netns_mctp *mns = &net->mctp;
+ struct mctp_sk_key *key, *tmp;
+ unsigned long flags;
+ int rc = -EAGAIN;
+ u8 tagbits;
+
+ /* be optimistic, alloc now */
+ key = kzalloc(sizeof(*key), GFP_KERNEL);
+ if (!key)
+ return -ENOMEM;
+ key->local_addr = saddr;
+ key->peer_addr = daddr;
+
+ /* 8 possible tag values */
+ tagbits = 0xff;
+
+ spin_lock_irqsave(&mns->keys_lock, flags);
+
+ /* Walk through the existing keys, looking for potential conflicting
+ * tags. If we find a conflict, clear that bit from tagbits
+ */
+ hlist_for_each_entry(tmp, &mns->keys, hlist) {
+ /* if we don't own the tag, it can't conflict */
+ if (tmp->tag & MCTP_HDR_FLAG_TO)
+ continue;
+
+ if ((tmp->peer_addr == daddr ||
+ tmp->peer_addr == MCTP_ADDR_ANY) &&
+ tmp->local_addr == saddr)
+ tagbits &= ~(1 << tmp->tag);
+
+ if (!tagbits)
+ break;
+ }
+
+ if (tagbits) {
+ key->tag = __ffs(tagbits);
+ mctp_reserve_tag(net, key, msk);
+ *tagp = key->tag;
+ rc = 0;
+ }
+
+ spin_unlock_irqrestore(&mns->keys_lock, flags);
+
+ if (!tagbits)
+ kfree(key);
+
+ return rc;
+}
+
/* routing lookups */
static bool mctp_rt_match_eid(struct mctp_route *rt,
unsigned int net, mctp_eid_t eid)
@@ -140,11 +343,13 @@ int mctp_do_route(struct mctp_route *rt, struct sk_buff *skb)
int mctp_local_output(struct sock *sk, struct mctp_route *rt,
struct sk_buff *skb, mctp_eid_t daddr, u8 req_tag)
{
+ struct mctp_sock *msk = container_of(sk, struct mctp_sock, sk);
struct mctp_skb_cb *cb = mctp_cb(skb);
struct mctp_hdr *hdr;
unsigned long flags;
mctp_eid_t saddr;
int rc;
+ u8 tag;
if (WARN_ON(!rt->dev))
return -EINVAL;
@@ -162,6 +367,15 @@ int mctp_local_output(struct sock *sk, struct mctp_route *rt,
if (rc)
return rc;
+ if (req_tag & MCTP_HDR_FLAG_TO) {
+ rc = mctp_alloc_local_tag(msk, saddr, daddr, &tag);
+ if (rc)
+ return rc;
+ tag |= MCTP_HDR_FLAG_TO;
+ } else {
+ tag = req_tag;
+ }
+
/* TODO: we have the route MTU here; packetise */
skb_reset_transport_header(skb);
@@ -171,8 +385,10 @@ int mctp_local_output(struct sock *sk, struct mctp_route *rt,
hdr->ver = 1;
hdr->dest = daddr;
hdr->src = saddr;
- hdr->flags_seq_tag = MCTP_HDR_FLAG_SOM | MCTP_HDR_FLAG_EOM; /* TODO */
+ hdr->flags_seq_tag = MCTP_HDR_FLAG_SOM | MCTP_HDR_FLAG_EOM | /* TODO */
+ tag;
+ skb->dev = rt->dev->dev;
skb->protocol = htons(ETH_P_MCTP);
skb->priority = 0;
@@ -529,6 +745,10 @@ static int __net_init mctp_routes_net_init(struct net *net)
struct netns_mctp *ns = &net->mctp;
INIT_LIST_HEAD(&ns->routes);
+ INIT_HLIST_HEAD(&ns->binds);
+ mutex_init(&ns->bind_lock);
+ INIT_HLIST_HEAD(&ns->keys);
+ spin_lock_init(&ns->keys_lock);
return 0;
}
--
2.30.2
^ permalink raw reply related [flat|nested] 23+ messages in thread
* [PATCH net-next v4 12/15] mctp: Implement message fragmentation & reassembly
2021-07-29 2:20 [PATCH net-next v4 00/15] Add Management Component Transport Protocol support Jeremy Kerr
` (10 preceding siblings ...)
2021-07-29 2:20 ` [PATCH net-next v4 11/15] mctp: Populate socket implementation Jeremy Kerr
@ 2021-07-29 2:20 ` Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 13/15] mctp: Add dest neighbour lladdr to route output Jeremy Kerr
` (3 subsequent siblings)
15 siblings, 0 replies; 23+ messages in thread
From: Jeremy Kerr @ 2021-07-29 2:20 UTC (permalink / raw)
To: netdev; +Cc: Matt Johnston, Andrew Jeffery, Jakub Kicinski, David S. Miller
This change implements MCTP fragmentation (based on route & device MTU),
and corresponding reassembly.
The MCTP specification only allows for fragmentation on the originating
message endpoint, and reassembly on the destination endpoint -
intermediate nodes do not need to reassemble/refragment. Consequently,
we only fragment in the local transmit path, and reassemble
locally-bound packets. Messages are required to be in-order, so we
simply cancel reassembly on out-of-order or missing packets.
In the fragmentation path, we just break up the message into MTU-sized
fragments; the skb structure is a simple copy for now, which we can later
improve with a shared data implementation.
For reassembly, we keep track of incoming message fragments using the
existing tag infrastructure, allocating a key on the (src,dest,tag)
tuple, and reassembles matching fragments into a skb->frag_list.
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
---
v2:
- limit max reassembly size
v3:
- fix comment typos
v4
- fix spurious rcu_read_unlock in route input
---
include/net/mctp.h | 25 ++-
net/mctp/af_mctp.c | 8 +
net/mctp/route.c | 372 ++++++++++++++++++++++++++++++++++++++++-----
3 files changed, 361 insertions(+), 44 deletions(-)
diff --git a/include/net/mctp.h b/include/net/mctp.h
index f2d98f6993c0..0a460ba185b8 100644
--- a/include/net/mctp.h
+++ b/include/net/mctp.h
@@ -84,9 +84,21 @@ struct mctp_sock {
* updates to either list are performed under the netns_mctp->keys
* lock.
*
- * - there is a single destruction path for a mctp_sk_key - through socket
- * unhash (see mctp_sk_unhash). This performs the list removal under
- * keys_lock.
+ * - a key may have a sk_buff attached as part of an in-progress message
+ * reassembly (->reasm_head). The reassembly context is protected by
+ * reasm_lock, which may be acquired with the keys lock (above) held, if
+ * necessary. Consequently, keys lock *cannot* be acquired with the
+ * reasm_lock held.
+ *
+ * - there are two destruction paths for a mctp_sk_key:
+ *
+ * - through socket unhash (see mctp_sk_unhash). This performs the list
+ * removal under keys_lock.
+ *
+ * - where a key is established to receive a reply message: after receiving
+ * the (complete) reply, or during reassembly errors. Here, we clean up
+ * the reassembly context (marking reasm_dead, to prevent another from
+ * starting), and remove the socket from the netns & socket lists.
*/
struct mctp_sk_key {
mctp_eid_t peer_addr;
@@ -102,6 +114,13 @@ struct mctp_sk_key {
/* per-socket list */
struct hlist_node sklist;
+ /* incoming fragment reassembly context */
+ spinlock_t reasm_lock;
+ struct sk_buff *reasm_head;
+ struct sk_buff **reasm_tailp;
+ bool reasm_dead;
+ u8 last_seq;
+
struct rcu_head rcu;
};
diff --git a/net/mctp/af_mctp.c b/net/mctp/af_mctp.c
index 52bd7f2b78db..9ca836df19d0 100644
--- a/net/mctp/af_mctp.c
+++ b/net/mctp/af_mctp.c
@@ -263,6 +263,14 @@ static void mctp_sk_unhash(struct sock *sk)
hlist_for_each_entry_safe(key, tmp, &msk->keys, sklist) {
hlist_del_rcu(&key->sklist);
hlist_del_rcu(&key->hlist);
+
+ spin_lock(&key->reasm_lock);
+ if (key->reasm_head)
+ kfree_skb(key->reasm_head);
+ key->reasm_head = NULL;
+ key->reasm_dead = true;
+ spin_unlock(&key->reasm_lock);
+
kfree_rcu(key, rcu);
}
spin_unlock_irqrestore(&net->mctp.keys_lock, flags);
diff --git a/net/mctp/route.c b/net/mctp/route.c
index cc9891672eaa..160220e6f241 100644
--- a/net/mctp/route.c
+++ b/net/mctp/route.c
@@ -23,6 +23,8 @@
#include <net/netlink.h>
#include <net/sock.h>
+static const unsigned int mctp_message_maxlen = 64 * 1024;
+
/* route output callbacks */
static int mctp_route_discard(struct mctp_route *route, struct sk_buff *skb)
{
@@ -105,14 +107,125 @@ static struct mctp_sk_key *mctp_lookup_key(struct net *net, struct sk_buff *skb,
return ret;
}
+static struct mctp_sk_key *mctp_key_alloc(struct mctp_sock *msk,
+ mctp_eid_t local, mctp_eid_t peer,
+ u8 tag, gfp_t gfp)
+{
+ struct mctp_sk_key *key;
+
+ key = kzalloc(sizeof(*key), gfp);
+ if (!key)
+ return NULL;
+
+ key->peer_addr = peer;
+ key->local_addr = local;
+ key->tag = tag;
+ key->sk = &msk->sk;
+ spin_lock_init(&key->reasm_lock);
+
+ return key;
+}
+
+static int mctp_key_add(struct mctp_sk_key *key, struct mctp_sock *msk)
+{
+ struct net *net = sock_net(&msk->sk);
+ struct mctp_sk_key *tmp;
+ unsigned long flags;
+ int rc = 0;
+
+ spin_lock_irqsave(&net->mctp.keys_lock, flags);
+
+ hlist_for_each_entry(tmp, &net->mctp.keys, hlist) {
+ if (mctp_key_match(tmp, key->local_addr, key->peer_addr,
+ key->tag)) {
+ rc = -EEXIST;
+ break;
+ }
+ }
+
+ if (!rc) {
+ hlist_add_head(&key->hlist, &net->mctp.keys);
+ hlist_add_head(&key->sklist, &msk->keys);
+ }
+
+ spin_unlock_irqrestore(&net->mctp.keys_lock, flags);
+
+ return rc;
+}
+
+/* Must be called with key->reasm_lock, which it will release. Will schedule
+ * the key for an RCU free.
+ */
+static void __mctp_key_unlock_drop(struct mctp_sk_key *key, struct net *net,
+ unsigned long flags)
+ __releases(&key->reasm_lock)
+{
+ struct sk_buff *skb;
+
+ skb = key->reasm_head;
+ key->reasm_head = NULL;
+ key->reasm_dead = true;
+ spin_unlock_irqrestore(&key->reasm_lock, flags);
+
+ spin_lock_irqsave(&net->mctp.keys_lock, flags);
+ hlist_del_rcu(&key->hlist);
+ hlist_del_rcu(&key->sklist);
+ spin_unlock_irqrestore(&net->mctp.keys_lock, flags);
+ kfree_rcu(key, rcu);
+
+ if (skb)
+ kfree_skb(skb);
+}
+
+static int mctp_frag_queue(struct mctp_sk_key *key, struct sk_buff *skb)
+{
+ struct mctp_hdr *hdr = mctp_hdr(skb);
+ u8 exp_seq, this_seq;
+
+ this_seq = (hdr->flags_seq_tag >> MCTP_HDR_SEQ_SHIFT)
+ & MCTP_HDR_SEQ_MASK;
+
+ if (!key->reasm_head) {
+ key->reasm_head = skb;
+ key->reasm_tailp = &(skb_shinfo(skb)->frag_list);
+ key->last_seq = this_seq;
+ return 0;
+ }
+
+ exp_seq = (key->last_seq + 1) & MCTP_HDR_SEQ_MASK;
+
+ if (this_seq != exp_seq)
+ return -EINVAL;
+
+ if (key->reasm_head->len + skb->len > mctp_message_maxlen)
+ return -EINVAL;
+
+ skb->next = NULL;
+ skb->sk = NULL;
+ *key->reasm_tailp = skb;
+ key->reasm_tailp = &skb->next;
+
+ key->last_seq = this_seq;
+
+ key->reasm_head->data_len += skb->len;
+ key->reasm_head->len += skb->len;
+ key->reasm_head->truesize += skb->truesize;
+
+ return 0;
+}
+
static int mctp_route_input(struct mctp_route *route, struct sk_buff *skb)
{
struct net *net = dev_net(skb->dev);
struct mctp_sk_key *key;
struct mctp_sock *msk;
struct mctp_hdr *mh;
+ unsigned long f;
+ u8 tag, flags;
+ int rc;
msk = NULL;
+ rc = -EINVAL;
/* we may be receiving a locally-routed packet; drop source sk
* accounting
@@ -121,50 +234,144 @@ static int mctp_route_input(struct mctp_route *route, struct sk_buff *skb)
/* ensure we have enough data for a header and a type */
if (skb->len < sizeof(struct mctp_hdr) + 1)
- goto drop;
+ goto out;
/* grab header, advance data ptr */
mh = mctp_hdr(skb);
skb_pull(skb, sizeof(struct mctp_hdr));
if (mh->ver != 1)
- goto drop;
+ goto out;
- /* TODO: reassembly */
- if ((mh->flags_seq_tag & (MCTP_HDR_FLAG_SOM | MCTP_HDR_FLAG_EOM))
- != (MCTP_HDR_FLAG_SOM | MCTP_HDR_FLAG_EOM))
- goto drop;
+ flags = mh->flags_seq_tag & (MCTP_HDR_FLAG_SOM | MCTP_HDR_FLAG_EOM);
+ tag = mh->flags_seq_tag & (MCTP_HDR_TAG_MASK | MCTP_HDR_FLAG_TO);
rcu_read_lock();
- /* 1. lookup socket matching (src,dest,tag) */
+
+ /* lookup socket / reasm context, exactly matching (src,dest,tag) */
key = mctp_lookup_key(net, skb, mh->src);
- /* 2. lookup socket macthing (BCAST,dest,tag) */
- if (!key)
- key = mctp_lookup_key(net, skb, MCTP_ADDR_ANY);
+ if (flags & MCTP_HDR_FLAG_SOM) {
+ if (key) {
+ msk = container_of(key->sk, struct mctp_sock, sk);
+ } else {
+ /* first response to a broadcast? do a more general
+ * key lookup to find the socket, but don't use this
+ * key for reassembly - we'll create a more specific
+ * one for future packets if required (ie, !EOM).
+ */
+ key = mctp_lookup_key(net, skb, MCTP_ADDR_ANY);
+ if (key) {
+ msk = container_of(key->sk,
+ struct mctp_sock, sk);
+ key = NULL;
+ }
+ }
- /* 3. SOM? -> lookup bound socket, conditionally (!EOM) create
- * mapping for future (1)/(2).
- */
- if (key)
- msk = container_of(key->sk, struct mctp_sock, sk);
- else if (!msk && (mh->flags_seq_tag & MCTP_HDR_FLAG_SOM))
- msk = mctp_lookup_bind(net, skb);
+ if (!key && !msk && (tag & MCTP_HDR_FLAG_TO))
+ msk = mctp_lookup_bind(net, skb);
- if (!msk)
- goto unlock_drop;
+ if (!msk) {
+ rc = -ENOENT;
+ goto out_unlock;
+ }
- sock_queue_rcv_skb(&msk->sk, skb);
+ /* single-packet message? deliver to socket, clean up any
+ * pending key.
+ */
+ if (flags & MCTP_HDR_FLAG_EOM) {
+ sock_queue_rcv_skb(&msk->sk, skb);
+ if (key) {
+ spin_lock_irqsave(&key->reasm_lock, f);
+ /* we've hit a pending reassembly; not much we
+ * can do but drop it
+ */
+ __mctp_key_unlock_drop(key, net, f);
+ }
+ rc = 0;
+ goto out_unlock;
+ }
- rcu_read_unlock();
+ /* broadcast response or a bind() - create a key for further
+ * packets for this message
+ */
+ if (!key) {
+ key = mctp_key_alloc(msk, mh->dest, mh->src,
+ tag, GFP_ATOMIC);
+ if (!key) {
+ rc = -ENOMEM;
+ goto out_unlock;
+ }
- return 0;
+ /* we can queue without the reasm lock here, as the
+ * key isn't observable yet
+ */
+ mctp_frag_queue(key, skb);
+
+ /* if the key_add fails, we've raced with another
+ * SOM packet with the same src, dest and tag. There's
+ * no way to distinguish future packets, so all we
+ * can do is drop; we'll free the skb on exit from
+ * this function.
+ */
+ rc = mctp_key_add(key, msk);
+ if (rc)
+ kfree(key);
+
+ } else {
+ /* existing key: start reassembly */
+ spin_lock_irqsave(&key->reasm_lock, f);
+
+ if (key->reasm_head || key->reasm_dead) {
+ /* duplicate start? drop everything */
+ __mctp_key_unlock_drop(key, net, f);
+ rc = -EEXIST;
+ } else {
+ rc = mctp_frag_queue(key, skb);
+ spin_unlock_irqrestore(&key->reasm_lock, f);
+ }
+ }
+
+ } else if (key) {
+ /* this packet continues a previous message; reassemble
+ * using the message-specific key
+ */
+
+ spin_lock_irqsave(&key->reasm_lock, f);
+
+ /* we need to be continuing an existing reassembly... */
+ if (!key->reasm_head)
+ rc = -EINVAL;
+ else
+ rc = mctp_frag_queue(key, skb);
+
+ /* end of message? deliver to socket, and we're done with
+ * the reassembly/response key
+ */
+ if (!rc && flags & MCTP_HDR_FLAG_EOM) {
+ sock_queue_rcv_skb(key->sk, key->reasm_head);
+ key->reasm_head = NULL;
+ __mctp_key_unlock_drop(key, net, f);
+ } else {
+ spin_unlock_irqrestore(&key->reasm_lock, f);
+ }
+
+ } else {
+ /* not a start, no matching key */
+ rc = -ENOENT;
+ }
-unlock_drop:
+out_unlock:
rcu_read_unlock();
-drop:
- kfree_skb(skb);
- return 0;
+out:
+ if (rc)
+ kfree_skb(skb);
+ return rc;
+}
+
+static unsigned int mctp_route_mtu(struct mctp_route *rt)
+{
+ return rt->mtu ?: READ_ONCE(rt->dev->dev->mtu);
}
static int mctp_route_output(struct mctp_route *route, struct sk_buff *skb)
@@ -228,8 +435,6 @@ static void mctp_reserve_tag(struct net *net, struct mctp_sk_key *key,
lockdep_assert_held(&mns->keys_lock);
- key->sk = &msk->sk;
-
/* we hold the net->key_lock here, allowing updates to both
* then net and sk
*/
@@ -251,11 +456,9 @@ static int mctp_alloc_local_tag(struct mctp_sock *msk,
u8 tagbits;
/* be optimistic, alloc now */
- key = kzalloc(sizeof(*key), GFP_KERNEL);
+ key = mctp_key_alloc(msk, saddr, daddr, 0, GFP_KERNEL);
if (!key)
return -ENOMEM;
- key->local_addr = saddr;
- key->peer_addr = daddr;
/* 8 possible tag values */
tagbits = 0xff;
@@ -340,6 +543,86 @@ int mctp_do_route(struct mctp_route *rt, struct sk_buff *skb)
return rc;
}
+static int mctp_do_fragment_route(struct mctp_route *rt, struct sk_buff *skb,
+ unsigned int mtu, u8 tag)
+{
+ const unsigned int hlen = sizeof(struct mctp_hdr);
+ struct mctp_hdr *hdr, *hdr2;
+ unsigned int pos, size;
+ struct sk_buff *skb2;
+ int rc;
+ u8 seq;
+
+ hdr = mctp_hdr(skb);
+ seq = 0;
+ rc = 0;
+
+ if (mtu < hlen + 1) {
+ kfree_skb(skb);
+ return -EMSGSIZE;
+ }
+
+ /* we've got the header */
+ skb_pull(skb, hlen);
+
+ for (pos = 0; pos < skb->len;) {
+ /* size of message payload */
+ size = min(mtu - hlen, skb->len - pos);
+
+ skb2 = alloc_skb(MCTP_HEADER_MAXLEN + hlen + size, GFP_KERNEL);
+ if (!skb2) {
+ rc = -ENOMEM;
+ break;
+ }
+
+ /* generic skb copy */
+ skb2->protocol = skb->protocol;
+ skb2->priority = skb->priority;
+ skb2->dev = skb->dev;
+ memcpy(skb2->cb, skb->cb, sizeof(skb2->cb));
+
+ if (skb->sk)
+ skb_set_owner_w(skb2, skb->sk);
+
+ /* establish packet */
+ skb_reserve(skb2, MCTP_HEADER_MAXLEN);
+ skb_reset_network_header(skb2);
+ skb_put(skb2, hlen + size);
+ skb2->transport_header = skb2->network_header + hlen;
+
+ /* copy header fields, calculate SOM/EOM flags & seq */
+ hdr2 = mctp_hdr(skb2);
+ hdr2->ver = hdr->ver;
+ hdr2->dest = hdr->dest;
+ hdr2->src = hdr->src;
+ hdr2->flags_seq_tag = tag &
+ (MCTP_HDR_TAG_MASK | MCTP_HDR_FLAG_TO);
+
+ if (pos == 0)
+ hdr2->flags_seq_tag |= MCTP_HDR_FLAG_SOM;
+
+ if (pos + size == skb->len)
+ hdr2->flags_seq_tag |= MCTP_HDR_FLAG_EOM;
+
+ hdr2->flags_seq_tag |= seq << MCTP_HDR_SEQ_SHIFT;
+
+ /* copy message payload */
+ skb_copy_bits(skb, pos, skb_transport_header(skb2), size);
+
+ /* do route, but don't drop the rt reference */
+ rc = rt->output(rt, skb2);
+ if (rc)
+ break;
+
+ seq = (seq + 1) & MCTP_HDR_SEQ_MASK;
+ pos += size;
+ }
+
+ mctp_route_release(rt);
+ consume_skb(skb);
+ return rc;
+}
+
int mctp_local_output(struct sock *sk, struct mctp_route *rt,
struct sk_buff *skb, mctp_eid_t daddr, u8 req_tag)
{
@@ -347,6 +630,7 @@ int mctp_local_output(struct sock *sk, struct mctp_route *rt,
struct mctp_skb_cb *cb = mctp_cb(skb);
struct mctp_hdr *hdr;
unsigned long flags;
+ unsigned int mtu;
mctp_eid_t saddr;
int rc;
u8 tag;
@@ -376,26 +660,32 @@ int mctp_local_output(struct sock *sk, struct mctp_route *rt,
tag = req_tag;
}
- /* TODO: we have the route MTU here; packetise */
+ skb->protocol = htons(ETH_P_MCTP);
+ skb->priority = 0;
skb_reset_transport_header(skb);
skb_push(skb, sizeof(struct mctp_hdr));
skb_reset_network_header(skb);
+ skb->dev = rt->dev->dev;
+
+ /* cb->net will have been set on initial ingress */
+ cb->src = saddr;
+
+ /* set up common header fields */
hdr = mctp_hdr(skb);
hdr->ver = 1;
hdr->dest = daddr;
hdr->src = saddr;
- hdr->flags_seq_tag = MCTP_HDR_FLAG_SOM | MCTP_HDR_FLAG_EOM | /* TODO */
- tag;
- skb->dev = rt->dev->dev;
- skb->protocol = htons(ETH_P_MCTP);
- skb->priority = 0;
+ mtu = mctp_route_mtu(rt);
- /* cb->net will have been set on initial ingress */
- cb->src = saddr;
-
- return mctp_do_route(rt, skb);
+ if (skb->len + sizeof(struct mctp_hdr) <= mtu) {
+ hdr->flags_seq_tag = MCTP_HDR_FLAG_SOM | MCTP_HDR_FLAG_EOM |
+ tag;
+ return mctp_do_route(rt, skb);
+ } else {
+ return mctp_do_fragment_route(rt, skb, mtu, tag);
+ }
}
/* route management */
--
2.30.2
^ permalink raw reply related [flat|nested] 23+ messages in thread
* [PATCH net-next v4 13/15] mctp: Add dest neighbour lladdr to route output
2021-07-29 2:20 [PATCH net-next v4 00/15] Add Management Component Transport Protocol support Jeremy Kerr
` (11 preceding siblings ...)
2021-07-29 2:20 ` [PATCH net-next v4 12/15] mctp: Implement message fragmentation & reassembly Jeremy Kerr
@ 2021-07-29 2:20 ` Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 14/15] mctp: Allow per-netns default networks Jeremy Kerr
` (2 subsequent siblings)
15 siblings, 0 replies; 23+ messages in thread
From: Jeremy Kerr @ 2021-07-29 2:20 UTC (permalink / raw)
To: netdev; +Cc: Matt Johnston, Andrew Jeffery, Jakub Kicinski, David S. Miller
From: Matt Johnston <matt@codeconstruct.com.au>
Now that we have a neighbour implementation, hook it up to the output
path to set the dest hardware address for outgoing packets.
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
---
net/mctp/route.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/net/mctp/route.c b/net/mctp/route.c
index 160220e6f241..38f0a7278520 100644
--- a/net/mctp/route.c
+++ b/net/mctp/route.c
@@ -376,6 +376,9 @@ static unsigned int mctp_route_mtu(struct mctp_route *rt)
static int mctp_route_output(struct mctp_route *route, struct sk_buff *skb)
{
+ struct mctp_hdr *hdr = mctp_hdr(skb);
+ char daddr_buf[MAX_ADDR_LEN];
+ char *daddr = NULL;
unsigned int mtu;
int rc;
@@ -387,9 +390,12 @@ static int mctp_route_output(struct mctp_route *route, struct sk_buff *skb)
return -EMSGSIZE;
}
- /* TODO: daddr (from rt->neigh), saddr (from device?) */
+ /* If lookup fails let the device handle daddr==NULL */
+ if (mctp_neigh_lookup(route->dev, hdr->dest, daddr_buf) == 0)
+ daddr = daddr_buf;
+
rc = dev_hard_header(skb, skb->dev, ntohs(skb->protocol),
- NULL, NULL, skb->len);
+ daddr, skb->dev->dev_addr, skb->len);
if (rc) {
kfree_skb(skb);
return -EHOSTUNREACH;
--
2.30.2
^ permalink raw reply related [flat|nested] 23+ messages in thread
* [PATCH net-next v4 14/15] mctp: Allow per-netns default networks
2021-07-29 2:20 [PATCH net-next v4 00/15] Add Management Component Transport Protocol support Jeremy Kerr
` (12 preceding siblings ...)
2021-07-29 2:20 ` [PATCH net-next v4 13/15] mctp: Add dest neighbour lladdr to route output Jeremy Kerr
@ 2021-07-29 2:20 ` Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 15/15] mctp: Add MCTP overview document Jeremy Kerr
2021-07-29 14:30 ` [PATCH net-next v4 00/15] Add Management Component Transport Protocol support patchwork-bot+netdevbpf
15 siblings, 0 replies; 23+ messages in thread
From: Jeremy Kerr @ 2021-07-29 2:20 UTC (permalink / raw)
To: netdev; +Cc: Matt Johnston, Andrew Jeffery, Jakub Kicinski, David S. Miller
From: Matt Johnston <matt@codeconstruct.com.au>
Currently we have a compile-time default network
(MCTP_INITIAL_DEFAULT_NET). This change introduces a default_net field
on the net namespace, allowing future configuration for new interfaces.
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
---
include/net/mctp.h | 2 ++
include/net/netns/mctp.h | 3 +++
include/uapi/linux/mctp.h | 1 -
net/mctp/af_mctp.c | 3 +++
net/mctp/device.c | 2 +-
net/mctp/route.c | 14 ++++++++++++++
6 files changed, 23 insertions(+), 2 deletions(-)
diff --git a/include/net/mctp.h b/include/net/mctp.h
index 0a460ba185b8..54bbe042c973 100644
--- a/include/net/mctp.h
+++ b/include/net/mctp.h
@@ -37,6 +37,8 @@ struct mctp_hdr {
#define MCTP_HEADER_MAXLEN 4
+#define MCTP_INITIAL_DEFAULT_NET 1
+
static inline bool mctp_address_ok(mctp_eid_t eid)
{
return eid >= 8 && eid < 255;
diff --git a/include/net/netns/mctp.h b/include/net/netns/mctp.h
index 14ae6d37e52a..acedef12a35e 100644
--- a/include/net/netns/mctp.h
+++ b/include/net/netns/mctp.h
@@ -25,6 +25,9 @@ struct netns_mctp {
spinlock_t keys_lock;
struct hlist_head keys;
+ /* MCTP network */
+ unsigned int default_net;
+
/* neighbour table */
struct mutex neigh_lock;
struct list_head neighbours;
diff --git a/include/uapi/linux/mctp.h b/include/uapi/linux/mctp.h
index a9d8edb3402b..52b54d13f385 100644
--- a/include/uapi/linux/mctp.h
+++ b/include/uapi/linux/mctp.h
@@ -26,7 +26,6 @@ struct sockaddr_mctp {
};
#define MCTP_NET_ANY 0x0
-#define MCTP_NET_DEFAULT 0x0
#define MCTP_ADDR_NULL 0x00
#define MCTP_ADDR_ANY 0xff
diff --git a/net/mctp/af_mctp.c b/net/mctp/af_mctp.c
index 9ca836df19d0..84f722d31fd7 100644
--- a/net/mctp/af_mctp.c
+++ b/net/mctp/af_mctp.c
@@ -94,6 +94,9 @@ static int mctp_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
if (!capable(CAP_NET_RAW))
return -EACCES;
+ if (addr->smctp_network == MCTP_NET_ANY)
+ addr->smctp_network = mctp_default_net(sock_net(sk));
+
rt = mctp_route_lookup(sock_net(sk), addr->smctp_network,
addr->smctp_addr.s_addr);
if (!rt)
diff --git a/net/mctp/device.c b/net/mctp/device.c
index aa049590acda..b9f38e765f61 100644
--- a/net/mctp/device.c
+++ b/net/mctp/device.c
@@ -267,7 +267,7 @@ static struct mctp_dev *mctp_add_dev(struct net_device *dev)
spin_lock_init(&mdev->addrs_lock);
- mdev->net = MCTP_INITIAL_DEFAULT_NET;
+ mdev->net = mctp_default_net(dev_net(dev));
/* associate to net_device */
rcu_assign_pointer(dev->mctp_ptr, mdev);
diff --git a/net/mctp/route.c b/net/mctp/route.c
index 38f0a7278520..b3101375c8e7 100644
--- a/net/mctp/route.c
+++ b/net/mctp/route.c
@@ -433,6 +433,19 @@ static struct mctp_route *mctp_route_alloc(void)
return rt;
}
+unsigned int mctp_default_net(struct net *net)
+{
+ return READ_ONCE(net->mctp.default_net);
+}
+
+int mctp_default_net_set(struct net *net, unsigned int index)
+{
+ if (index == 0)
+ return -EINVAL;
+ WRITE_ONCE(net->mctp.default_net, index);
+ return 0;
+}
+
/* tag management */
static void mctp_reserve_tag(struct net *net, struct mctp_sk_key *key,
struct mctp_sock *msk)
@@ -1045,6 +1058,7 @@ static int __net_init mctp_routes_net_init(struct net *net)
mutex_init(&ns->bind_lock);
INIT_HLIST_HEAD(&ns->keys);
spin_lock_init(&ns->keys_lock);
+ WARN_ON(mctp_default_net_set(net, MCTP_INITIAL_DEFAULT_NET));
return 0;
}
--
2.30.2
^ permalink raw reply related [flat|nested] 23+ messages in thread
* [PATCH net-next v4 15/15] mctp: Add MCTP overview document
2021-07-29 2:20 [PATCH net-next v4 00/15] Add Management Component Transport Protocol support Jeremy Kerr
` (13 preceding siblings ...)
2021-07-29 2:20 ` [PATCH net-next v4 14/15] mctp: Allow per-netns default networks Jeremy Kerr
@ 2021-07-29 2:20 ` Jeremy Kerr
2021-10-15 13:10 ` Eugene Syromiatnikov
2021-07-29 14:30 ` [PATCH net-next v4 00/15] Add Management Component Transport Protocol support patchwork-bot+netdevbpf
15 siblings, 1 reply; 23+ messages in thread
From: Jeremy Kerr @ 2021-07-29 2:20 UTC (permalink / raw)
To: netdev
Cc: Matt Johnston, Andrew Jeffery, Jakub Kicinski, David S. Miller,
linux-doc, Jonathan Corbet
This change adds a brief document about the sockets API provided for
sending and receiving MCTP messages from userspace.
This is roughly based on the OpenBMC design document, at:
https://github.com/openbmc/docs/blob/master/designs/mctp/mctp-kernel.md
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
---
v2:
- Controller -> component
---
Documentation/networking/index.rst | 1 +
Documentation/networking/mctp.rst | 213 +++++++++++++++++++++++++++++
MAINTAINERS | 1 +
3 files changed, 215 insertions(+)
create mode 100644 Documentation/networking/mctp.rst
diff --git a/Documentation/networking/index.rst b/Documentation/networking/index.rst
index a91a2739f8ed..58bc8cd367c6 100644
--- a/Documentation/networking/index.rst
+++ b/Documentation/networking/index.rst
@@ -69,6 +69,7 @@ Contents:
l2tp
lapb-module
mac80211-injection
+ mctp
mpls-sysctl
mptcp-sysctl
multiqueue
diff --git a/Documentation/networking/mctp.rst b/Documentation/networking/mctp.rst
new file mode 100644
index 000000000000..6100cdc220f6
--- /dev/null
+++ b/Documentation/networking/mctp.rst
@@ -0,0 +1,213 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+==============================================
+Management Component Transport Protocol (MCTP)
+==============================================
+
+net/mctp/ contains protocol support for MCTP, as defined by DMTF standard
+DSP0236. Physical interface drivers ("bindings" in the specification) are
+provided in drivers/net/mctp/.
+
+The core code provides a socket-based interface to send and receive MCTP
+messages, through an AF_MCTP, SOCK_DGRAM socket.
+
+Structure: interfaces & networks
+================================
+
+The kernel models the local MCTP topology through two items: interfaces and
+networks.
+
+An interface (or "link") is an instance of an MCTP physical transport binding
+(as defined by DSP0236, section 3.2.47), likely connected to a specific hardware
+device. This is represented as a ``struct netdevice``.
+
+A network defines a unique address space for MCTP endpoints by endpoint-ID
+(described by DSP0236, section 3.2.31). A network has a user-visible identifier
+to allow references from userspace. Route definitions are specific to one
+network.
+
+Interfaces are associated with one network. A network may be associated with one
+or more interfaces.
+
+If multiple networks are present, each may contain endpoint IDs (EIDs) that are
+also present on other networks.
+
+Sockets API
+===========
+
+Protocol definitions
+--------------------
+
+MCTP uses ``AF_MCTP`` / ``PF_MCTP`` for the address- and protocol- families.
+Since MCTP is message-based, only ``SOCK_DGRAM`` sockets are supported.
+
+.. code-block:: C
+
+ int sd = socket(AF_MCTP, SOCK_DGRAM, 0);
+
+The only (current) value for the ``protocol`` argument is 0.
+
+As with all socket address families, source and destination addresses are
+specified with a ``sockaddr`` type, with a single-byte endpoint address:
+
+.. code-block:: C
+
+ typedef __u8 mctp_eid_t;
+
+ struct mctp_addr {
+ mctp_eid_t s_addr;
+ };
+
+ struct sockaddr_mctp {
+ unsigned short int smctp_family;
+ int smctp_network;
+ struct mctp_addr smctp_addr;
+ __u8 smctp_type;
+ __u8 smctp_tag;
+ };
+
+ #define MCTP_NET_ANY 0x0
+ #define MCTP_ADDR_ANY 0xff
+
+
+Syscall behaviour
+-----------------
+
+The following sections describe the MCTP-specific behaviours of the standard
+socket system calls. These behaviours have been chosen to map closely to the
+existing sockets APIs.
+
+``bind()`` : set local socket address
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Sockets that receive incoming request packets will bind to a local address,
+using the ``bind()`` syscall.
+
+.. code-block:: C
+
+ struct sockaddr_mctp addr;
+
+ addr.smctp_family = AF_MCTP;
+ addr.smctp_network = MCTP_NET_ANY;
+ addr.smctp_addr.s_addr = MCTP_ADDR_ANY;
+ addr.smctp_type = MCTP_TYPE_PLDM;
+ addr.smctp_tag = MCTP_TAG_OWNER;
+
+ int rc = bind(sd, (struct sockaddr *)&addr, sizeof(addr));
+
+This establishes the local address of the socket. Incoming MCTP messages that
+match the network, address, and message type will be received by this socket.
+The reference to 'incoming' is important here; a bound socket will only receive
+messages with the TO bit set, to indicate an incoming request message, rather
+than a response.
+
+The ``smctp_tag`` value will configure the tags accepted from the remote side of
+this socket. Given the above, the only valid value is ``MCTP_TAG_OWNER``, which
+will result in remotely "owned" tags being routed to this socket. Since
+``MCTP_TAG_OWNER`` is set, the 3 least-significant bits of ``smctp_tag`` are not
+used; callers must set them to zero.
+
+A ``smctp_network`` value of ``MCTP_NET_ANY`` will configure the socket to
+receive incoming packets from any locally-connected network. A specific network
+value will cause the socket to only receive incoming messages from that network.
+
+The ``smctp_addr`` field specifies a local address to bind to. A value of
+``MCTP_ADDR_ANY`` configures the socket to receive messages addressed to any
+local destination EID.
+
+The ``smctp_type`` field specifies which message types to receive. Only the
+lower 7 bits of the type is matched on incoming messages (ie., the
+most-significant IC bit is not part of the match). This results in the socket
+receiving packets with and without a message integrity check footer.
+
+``sendto()``, ``sendmsg()``, ``send()`` : transmit an MCTP message
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+An MCTP message is transmitted using one of the ``sendto()``, ``sendmsg()`` or
+``send()`` syscalls. Using ``sendto()`` as the primary example:
+
+.. code-block:: C
+
+ struct sockaddr_mctp addr;
+ char buf[14];
+ ssize_t len;
+
+ /* set message destination */
+ addr.smctp_family = AF_MCTP;
+ addr.smctp_network = 0;
+ addr.smctp_addr.s_addr = 8;
+ addr.smctp_tag = MCTP_TAG_OWNER;
+ addr.smctp_type = MCTP_TYPE_ECHO;
+
+ /* arbitrary message to send, with message-type header */
+ buf[0] = MCTP_TYPE_ECHO;
+ memcpy(buf + 1, "hello, world!", sizeof(buf) - 1);
+
+ len = sendto(sd, buf, sizeof(buf), 0,
+ (struct sockaddr_mctp *)&addr, sizeof(addr));
+
+The network and address fields of ``addr`` define the remote address to send to.
+If ``smctp_tag`` has the ``MCTP_TAG_OWNER``, the kernel will ignore any bits set
+in ``MCTP_TAG_VALUE``, and generate a tag value suitable for the destination
+EID. If ``MCTP_TAG_OWNER`` is not set, the message will be sent with the tag
+value as specified. If a tag value cannot be allocated, the system call will
+report an errno of ``EAGAIN``.
+
+The application must provide the message type byte as the first byte of the
+message buffer passed to ``sendto()``. If a message integrity check is to be
+included in the transmitted message, it must also be provided in the message
+buffer, and the most-significant bit of the message type byte must be 1.
+
+The ``sendmsg()`` system call allows a more compact argument interface, and the
+message buffer to be specified as a scatter-gather list. At present no ancillary
+message types (used for the ``msg_control`` data passed to ``sendmsg()``) are
+defined.
+
+Transmitting a message on an unconnected socket with ``MCTP_TAG_OWNER``
+specified will cause an allocation of a tag, if no valid tag is already
+allocated for that destination. The (destination-eid,tag) tuple acts as an
+implicit local socket address, to allow the socket to receive responses to this
+outgoing message. If any previous allocation has been performed (to for a
+different remote EID), that allocation is lost.
+
+Sockets will only receive responses to requests they have sent (with TO=1) and
+may only respond (with TO=0) to requests they have received.
+
+``recvfrom()``, ``recvmsg()``, ``recv()`` : receive an MCTP message
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+An MCTP message can be received by an application using one of the
+``recvfrom()``, ``recvmsg()``, or ``recv()`` system calls. Using ``recvfrom()``
+as the primary example:
+
+.. code-block:: C
+
+ struct sockaddr_mctp addr;
+ socklen_t addrlen;
+ char buf[14];
+ ssize_t len;
+
+ addrlen = sizeof(addr);
+
+ len = recvfrom(sd, buf, sizeof(buf), 0,
+ (struct sockaddr_mctp *)&addr, &addrlen);
+
+ /* We can expect addr to describe an MCTP address */
+ assert(addrlen >= sizeof(buf));
+ assert(addr.smctp_family == AF_MCTP);
+
+ printf("received %zd bytes from remote EID %d\n", rc, addr.smctp_addr);
+
+The address argument to ``recvfrom`` and ``recvmsg`` is populated with the
+remote address of the incoming message, including tag value (this will be needed
+in order to reply to the message).
+
+The first byte of the message buffer will contain the message type byte. If an
+integrity check follows the message, it will be included in the received buffer.
+
+The ``recv()`` system call behaves in a similar way, but does not provide a
+remote address to the application. Therefore, these are only useful if the
+remote address is already known, or the message does not require a reply.
+
+Like the send calls, sockets will only receive responses to requests they have
+sent (TO=1) and may only respond (TO=0) to requests they have received.
diff --git a/MAINTAINERS b/MAINTAINERS
index 4ca73465e690..73beb91891ee 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11037,6 +11037,7 @@ M: Jeremy Kerr <jk@codeconstruct.com.au>
M: Matt Johnston <matt@codeconstruct.com.au>
L: netdev@vger.kernel.org
S: Maintained
+F: Documentation/networking/mctp.rst
F: drivers/net/mctp/
F: include/net/mctp.h
F: include/net/mctpdevice.h
--
2.30.2
^ permalink raw reply related [flat|nested] 23+ messages in thread
* Re: [PATCH net-next v4 00/15] Add Management Component Transport Protocol support
2021-07-29 2:20 [PATCH net-next v4 00/15] Add Management Component Transport Protocol support Jeremy Kerr
` (14 preceding siblings ...)
2021-07-29 2:20 ` [PATCH net-next v4 15/15] mctp: Add MCTP overview document Jeremy Kerr
@ 2021-07-29 14:30 ` patchwork-bot+netdevbpf
15 siblings, 0 replies; 23+ messages in thread
From: patchwork-bot+netdevbpf @ 2021-07-29 14:30 UTC (permalink / raw)
To: Jeremy Kerr
Cc: netdev, matt, andrew, kuba, davem, linux-doc, corbet, paul,
stephen.smalley.work, eparis, selinux
Hello:
This series was applied to netdev/net-next.git (refs/heads/master):
On Thu, 29 Jul 2021 10:20:38 +0800 you wrote:
> This series adds core MCTP support to the kernel. From the Kconfig
> description:
>
> Management Component Transport Protocol (MCTP) is an in-system
> protocol for communicating between management controllers and
> their managed devices (peripherals, host processors, etc.). The
> protocol is defined by DMTF specification DSP0236.
>
> [...]
Here is the summary with links:
- [net-next,v4,01/15] mctp: Add MCTP base
https://git.kernel.org/netdev/net-next/c/bc49d8169aa7
- [net-next,v4,02/15] mctp: Add base socket/protocol definitions
https://git.kernel.org/netdev/net-next/c/8f601a1e4f8c
- [net-next,v4,03/15] mctp: Add base packet definitions
https://git.kernel.org/netdev/net-next/c/2c8e2e9aec79
- [net-next,v4,04/15] mctp: Add sockaddr_mctp to uapi
https://git.kernel.org/netdev/net-next/c/60fc63981693
- [net-next,v4,05/15] mctp: Add initial driver infrastructure
https://git.kernel.org/netdev/net-next/c/4b2e69305cbb
- [net-next,v4,06/15] mctp: Add device handling and netlink interface
https://git.kernel.org/netdev/net-next/c/583be982d934
- [net-next,v4,07/15] mctp: Add initial routing framework
https://git.kernel.org/netdev/net-next/c/889b7da23abf
- [net-next,v4,08/15] mctp: Add netlink route management
https://git.kernel.org/netdev/net-next/c/06d2f4c583a7
- [net-next,v4,09/15] mctp: Add neighbour implementation
https://git.kernel.org/netdev/net-next/c/4d8b9319282a
- [net-next,v4,10/15] mctp: Add neighbour netlink interface
https://git.kernel.org/netdev/net-next/c/831119f88781
- [net-next,v4,11/15] mctp: Populate socket implementation
https://git.kernel.org/netdev/net-next/c/833ef3b91de6
- [net-next,v4,12/15] mctp: Implement message fragmentation & reassembly
https://git.kernel.org/netdev/net-next/c/4a992bbd3650
- [net-next,v4,13/15] mctp: Add dest neighbour lladdr to route output
https://git.kernel.org/netdev/net-next/c/26ab3fcaf235
- [net-next,v4,14/15] mctp: Allow per-netns default networks
https://git.kernel.org/netdev/net-next/c/03f2bbc4ee57
- [net-next,v4,15/15] mctp: Add MCTP overview document
https://git.kernel.org/netdev/net-next/c/6a2d98b18900
You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html
^ permalink raw reply [flat|nested] 23+ messages in thread
* Re: [PATCH net-next v4 04/15] mctp: Add sockaddr_mctp to uapi
2021-07-29 2:20 ` [PATCH net-next v4 04/15] mctp: Add sockaddr_mctp to uapi Jeremy Kerr
@ 2021-10-14 18:34 ` Eugene Syromiatnikov
2021-10-15 1:18 ` Jeremy Kerr
2021-10-15 6:27 ` Geert Uytterhoeven
2021-10-15 17:00 ` Eugene Syromiatnikov
1 sibling, 2 replies; 23+ messages in thread
From: Eugene Syromiatnikov @ 2021-10-14 18:34 UTC (permalink / raw)
To: Jeremy Kerr
Cc: netdev, Matt Johnston, Andrew Jeffery, Jakub Kicinski,
David S. Miller, linux-m68k
On Thu, Jul 29, 2021 at 10:20:42AM +0800, Jeremy Kerr wrote:
> This change introduces the user-visible MCTP header, containing the
> protocol-specific addressing definitions.
[...]
> --- a/include/uapi/linux/mctp.h
> +++ b/include/uapi/linux/mctp.h
> @@ -9,7 +9,28 @@
> #ifndef __UAPI_MCTP_H
> #define __UAPI_MCTP_H
>
> +#include <linux/types.h>
> +
> +typedef __u8 mctp_eid_t;
> +
> +struct mctp_addr {
> + mctp_eid_t s_addr;
> +};
> +
> struct sockaddr_mctp {
> + unsigned short int smctp_family;
This gap makes the size of struct sockaddr_mctp 2 bytes less at least
on m68k, are you fine with that?
> + int smctp_network;
> + struct mctp_addr smctp_addr;
> + __u8 smctp_type;
> + __u8 smctp_tag;
> };
^ permalink raw reply [flat|nested] 23+ messages in thread
* Re: [PATCH net-next v4 04/15] mctp: Add sockaddr_mctp to uapi
2021-10-14 18:34 ` Eugene Syromiatnikov
@ 2021-10-15 1:18 ` Jeremy Kerr
2021-10-15 6:27 ` Geert Uytterhoeven
1 sibling, 0 replies; 23+ messages in thread
From: Jeremy Kerr @ 2021-10-15 1:18 UTC (permalink / raw)
To: Eugene Syromiatnikov
Cc: netdev, Matt Johnston, Andrew Jeffery, Jakub Kicinski,
David S. Miller, linux-m68k
Hi Eugene,
Thanks for taking a look at these!
> > +typedef __u8 mctp_eid_t;
> > +
> > +struct mctp_addr {
> > + mctp_eid_t s_addr;
> > +};
> > +
> > struct sockaddr_mctp {
> > + unsigned short int smctp_family;
>
> This gap makes the size of struct sockaddr_mctp 2 bytes less at least
> on m68k, are you fine with that?
Yep, that's OK from the protocol implementation side; this layout better
matches the "hierarchy" of the MCTP addressing. If we go for optimal
packing, the order of the members makes somewhat less sense. We could
add padding members, but I'm not sure that's worth it...
I noticed a few other protocol implementations doing similar things, so
assume it isn't an issue - it's all arch-specific ABI anyway, right?
> > + int smctp_network;
> > + struct mctp_addr smctp_addr;
> > + __u8 smctp_type;
> > + __u8 smctp_tag;
> > };
Cheers,
Jeremy
^ permalink raw reply [flat|nested] 23+ messages in thread
* Re: [PATCH net-next v4 04/15] mctp: Add sockaddr_mctp to uapi
2021-10-14 18:34 ` Eugene Syromiatnikov
2021-10-15 1:18 ` Jeremy Kerr
@ 2021-10-15 6:27 ` Geert Uytterhoeven
1 sibling, 0 replies; 23+ messages in thread
From: Geert Uytterhoeven @ 2021-10-15 6:27 UTC (permalink / raw)
To: Eugene Syromiatnikov
Cc: Jeremy Kerr, netdev, Matt Johnston, Andrew Jeffery,
Jakub Kicinski, David S. Miller, linux-m68k
On Fri, Oct 15, 2021 at 12:32 AM Eugene Syromiatnikov <esyr@redhat.com> wrote:
> On Thu, Jul 29, 2021 at 10:20:42AM +0800, Jeremy Kerr wrote:
> > This change introduces the user-visible MCTP header, containing the
> > protocol-specific addressing definitions.
>
> [...]
>
> > --- a/include/uapi/linux/mctp.h
> > +++ b/include/uapi/linux/mctp.h
> > @@ -9,7 +9,28 @@
> > #ifndef __UAPI_MCTP_H
> > #define __UAPI_MCTP_H
> >
> > +#include <linux/types.h>
> > +
> > +typedef __u8 mctp_eid_t;
> > +
> > +struct mctp_addr {
> > + mctp_eid_t s_addr;
> > +};
> > +
> > struct sockaddr_mctp {
> > + unsigned short int smctp_family;
>
> This gap makes the size of struct sockaddr_mctp 2 bytes less at least
> on m68k, are you fine with that?
>
> > + int smctp_network;
> > + struct mctp_addr smctp_addr;
> > + __u8 smctp_type;
> > + __u8 smctp_tag;
And it may be wise to add 1 byte of explicit padding here?
Or is there a good reason not to do so?
> > };
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
^ permalink raw reply [flat|nested] 23+ messages in thread
* Re: [PATCH net-next v4 15/15] mctp: Add MCTP overview document
2021-07-29 2:20 ` [PATCH net-next v4 15/15] mctp: Add MCTP overview document Jeremy Kerr
@ 2021-10-15 13:10 ` Eugene Syromiatnikov
0 siblings, 0 replies; 23+ messages in thread
From: Eugene Syromiatnikov @ 2021-10-15 13:10 UTC (permalink / raw)
To: Jeremy Kerr
Cc: netdev, Matt Johnston, Andrew Jeffery, Jakub Kicinski,
David S. Miller, linux-doc, Jonathan Corbet
On Thu, Jul 29, 2021 at 10:20:53AM +0800, Jeremy Kerr wrote:
> This change adds a brief document about the sockets API provided for
> sending and receiving MCTP messages from userspace.
[...]
> diff --git a/Documentation/networking/mctp.rst b/Documentation/networking/mctp.rst
[...]
> +``bind()`` : set local socket address
> +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> +
> +Sockets that receive incoming request packets will bind to a local address,
> +using the ``bind()`` syscall.
> +
> +.. code-block:: C
> +
> + struct sockaddr_mctp addr;
> +
> + addr.smctp_family = AF_MCTP;
> + addr.smctp_network = MCTP_NET_ANY;
> + addr.smctp_addr.s_addr = MCTP_ADDR_ANY;
> + addr.smctp_type = MCTP_TYPE_PLDM;
[...]
> +``sendto()``, ``sendmsg()``, ``send()`` : transmit an MCTP message
> +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> +
> +An MCTP message is transmitted using one of the ``sendto()``, ``sendmsg()`` or
> +``send()`` syscalls. Using ``sendto()`` as the primary example:
> +
> +.. code-block:: C
> +
> + struct sockaddr_mctp addr;
> + char buf[14];
> + ssize_t len;
> +
> + /* set message destination */
> + addr.smctp_family = AF_MCTP;
> + addr.smctp_network = 0;
> + addr.smctp_addr.s_addr = 8;
> + addr.smctp_tag = MCTP_TAG_OWNER;
> + addr.smctp_type = MCTP_TYPE_ECHO;
While MCTP_TYPE_PLDM and MCTP_TYPE_ECHO are mentioned
in the documentation, their definition is currently missing in the UAPI
header (or anywhere in the source tree at all). Is that expected?
^ permalink raw reply [flat|nested] 23+ messages in thread
* Re: [PATCH net-next v4 04/15] mctp: Add sockaddr_mctp to uapi
2021-07-29 2:20 ` [PATCH net-next v4 04/15] mctp: Add sockaddr_mctp to uapi Jeremy Kerr
2021-10-14 18:34 ` Eugene Syromiatnikov
@ 2021-10-15 17:00 ` Eugene Syromiatnikov
2021-10-16 2:12 ` Jeremy Kerr
1 sibling, 1 reply; 23+ messages in thread
From: Eugene Syromiatnikov @ 2021-10-15 17:00 UTC (permalink / raw)
To: Jeremy Kerr
Cc: netdev, Matt Johnston, Andrew Jeffery, Jakub Kicinski, David S. Miller
On Thu, Jul 29, 2021 at 10:20:42AM +0800, Jeremy Kerr wrote:
> struct sockaddr_mctp {
> + unsigned short int smctp_family;
> + int smctp_network;
struct mctp_skb_cb.net (as well as struct mctp_dev.net) are unsigned,
is it intentional that this field (along with struct mctp_sock.bind_net)
differs in signedness?
^ permalink raw reply [flat|nested] 23+ messages in thread
* Re: [PATCH net-next v4 04/15] mctp: Add sockaddr_mctp to uapi
2021-10-15 17:00 ` Eugene Syromiatnikov
@ 2021-10-16 2:12 ` Jeremy Kerr
0 siblings, 0 replies; 23+ messages in thread
From: Jeremy Kerr @ 2021-10-16 2:12 UTC (permalink / raw)
To: Eugene Syromiatnikov
Cc: netdev, Matt Johnston, Andrew Jeffery, Jakub Kicinski, David S. Miller
Hi Eugene,
> On Thu, Jul 29, 2021 at 10:20:42AM +0800, Jeremy Kerr wrote:
> > struct sockaddr_mctp {
> > + unsigned short int smctp_family;
> > + int smctp_network;
>
> struct mctp_skb_cb.net (as well as struct mctp_dev.net) are unsigned,
> is it intentional that this field (along with struct
> mctp_sock.bind_net) differs in signedness?
No, that's not intentional - I'll submit a patch to unify those.
Thanks for the review.
Cheers,
Jeremy
^ permalink raw reply [flat|nested] 23+ messages in thread
end of thread, other threads:[~2021-10-16 2:13 UTC | newest]
Thread overview: 23+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-07-29 2:20 [PATCH net-next v4 00/15] Add Management Component Transport Protocol support Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 01/15] mctp: Add MCTP base Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 02/15] mctp: Add base socket/protocol definitions Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 03/15] mctp: Add base packet definitions Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 04/15] mctp: Add sockaddr_mctp to uapi Jeremy Kerr
2021-10-14 18:34 ` Eugene Syromiatnikov
2021-10-15 1:18 ` Jeremy Kerr
2021-10-15 6:27 ` Geert Uytterhoeven
2021-10-15 17:00 ` Eugene Syromiatnikov
2021-10-16 2:12 ` Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 05/15] mctp: Add initial driver infrastructure Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 06/15] mctp: Add device handling and netlink interface Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 07/15] mctp: Add initial routing framework Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 08/15] mctp: Add netlink route management Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 09/15] mctp: Add neighbour implementation Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 10/15] mctp: Add neighbour netlink interface Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 11/15] mctp: Populate socket implementation Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 12/15] mctp: Implement message fragmentation & reassembly Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 13/15] mctp: Add dest neighbour lladdr to route output Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 14/15] mctp: Allow per-netns default networks Jeremy Kerr
2021-07-29 2:20 ` [PATCH net-next v4 15/15] mctp: Add MCTP overview document Jeremy Kerr
2021-10-15 13:10 ` Eugene Syromiatnikov
2021-07-29 14:30 ` [PATCH net-next v4 00/15] Add Management Component Transport Protocol support patchwork-bot+netdevbpf
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