* [PATCH v2 0/9] net: add support for IPv6 Segment Routing
@ 2016-10-26 15:54 David Lebrun
2016-10-26 15:54 ` [PATCH v2 1/9] ipv6: implement dataplane support for rthdr type 4 (Segment Routing Header) David Lebrun
` (9 more replies)
0 siblings, 10 replies; 15+ messages in thread
From: David Lebrun @ 2016-10-26 15:54 UTC (permalink / raw)
To: netdev; +Cc: David Lebrun
v2:
- Remove packed attribute from sr6 struct and replaced unaligned
16-bit flags with two 8-bit flags.
- SR code now included by default. Option CONFIG_IPV6_SEG6_HMAC
exists for HMAC support (which requires crypto dependencies).
- Replace "hidden" calls to mutex_{un,}lock to direct calls.
- Fix reverse xmas tree coding style.
- Fix cast-from-void*'s.
- Update skb->csum to account for SR modifications.
- Add dst_cache in seg6_output.
Segment Routing (SR) is a source routing paradigm, architecturally
defined in draft-ietf-spring-segment-routing-09 [1]. The IPv6 flavor of
SR is defined in draft-ietf-6man-segment-routing-header-02 [2].
The main idea is that an SR-enabled packet contains a list of segments,
which represent mandatory waypoints. Each waypoint is called a segment
endpoint. The SR-enabled packet is routed normally (e.g. shortest path)
between the segment endpoints. A node that inserts an SRH into a packet
is called an ingress node, and a node that is the last segment endpoint
is called an egress node.
>From an IPv6 viewpoint, an SR-enabled packet contains an IPv6 extension
header, which is a Routing Header type 4, defined as follows:
struct ipv6_sr_hdr {
__u8 nexthdr;
__u8 hdrlen;
__u8 type;
__u8 segments_left;
__u8 first_segment;
__be16 flags;
__u8 reserved;
struct in6_addr segments[0];
} __attribute__((packed));
The first 4 bytes of the SRH is consistent with the Routing Header
definition in RFC 2460. The type is set to `4' (SRH).
Each segment is encoded as an IPv6 address. The segments are encoded in
reverse order: segments[0] is the last segment of the path, and
segments[first_segment] is the first segment of the path.
segments[segments_left] points to the currently active segment and
segments_left is decremented at each segment endpoint.
There exist two ways for a packet to receive an SRH, we call them
encap mode and inline mode. In the encap mode, the packet is encapsulated
in an outer IPv6 header that contains the SRH. The inner (original) packet
is not modified. A virtual tunnel is thus created between the ingress node
(the node that encapsulates) and the egress node (the last segment of the path).
Once an encapsulated SR packet reaches the egress node, the node decapsulates
the packet and performs a routing decision on the inner packet. This kind of
SRH insertion is intended to use for routers that encapsulates in-transit
packet.
The second SRH insertion method, the inline mode, acts by directly inserting
the SRH right after the IPv6 header of the original packet. For this method,
if a particular flag (SR6_FLAG_CLEANUP) is set, then the penultimate segment
endpoint must strip the SRH from the packet before forwarding it to the last
segment endpoint. This insertion method is intended to use for endhosts,
however it is also used for in-transit packets by some industry actors.
Finally, the SRH may contain TLVs after the segments list. Several types of
TLVs are defined, but we currently consider only the HMAC TLV. This TLV is
an answer to the deprecation of the RH0 and enables to ensure the authenticity
and integrity of the SRH. The HMAC text contains the flags, the first_segment
index, the full list of segments, and the source address of the packet. While
SR is intended to use mostly within a single administrative domain, the HMAC
TLV allows to verify SR packets coming from an untrusted source.
This patches series implements support for the IPv6 flavor of SR and is
logically divided into the following components:
(1) Data plane support (patch 01). This patch adds a function
in net/ipv6/exthdrs.c to handle the Routing Header type 4.
It enables the kernel to act as a segment endpoint, by supporting
the following operations: decrementation of the segments_left field,
cleanup flag support (removal of the SRH if we are the penultimate
segment endpoint) and decapsulation of the inner packet as an egress
node.
(2) Control plane support (patches 02..03 and 07..09). These patches enables
to insert SRH on locally emitted and/or forwarded packets, both with
encap mode and with inline mode. The SRH insertion is controlled through
the lightweight tunnels mechanism. Furthermore, patch 08 enables the
applications to insert an SRH on a per-socket basis, through the
setsockopt() system call. The mechanism to specify a per-socket
Routing Header was already defined for RH0 and no special modification
was performed on this side. However, the code to actually push the RH
onto the packets had to be adapted for the SRH specifications.
(3) HMAC support (patches 04..06). These patches adds the support of the
HMAC TLV verification for the dataplane part, and generation for
the control plane part. Two hashing algorithms are supported
(SHA-1 as legacy and SHA-256 as required by the IETF draft), but
additional algorithms can be easily supported by simply adding an
entry into an array.
[1] https://tools.ietf.org/html/draft-ietf-spring-segment-routing-09
[2] https://tools.ietf.org/html/draft-ietf-6man-segment-routing-header-02
David Lebrun (9):
ipv6: implement dataplane support for rthdr type 4 (Segment Routing
Header)
ipv6: sr: add code base for control plane support of SR-IPv6
ipv6: sr: add support for SRH encapsulation and injection with
lwtunnels
ipv6: sr: add core files for SR HMAC support
ipv6: sr: implement API to control SR HMAC structure
ipv6: sr: add calls to verify and insert HMAC signatures
ipv6: add source address argument for ipv6_push_nfrag_opts
ipv6: sr: add support for SRH injection through setsockopt
ipv6: sr: add documentation file for per-interface sysctls
Documentation/networking/seg6-sysctl.txt | 18 ++
include/linux/ipv6.h | 4 +
include/linux/seg6.h | 6 +
include/linux/seg6_genl.h | 6 +
include/linux/seg6_hmac.h | 6 +
include/linux/seg6_iptunnel.h | 6 +
include/net/ipv6.h | 3 +-
include/net/netns/ipv6.h | 1 +
include/net/seg6.h | 41 +++
include/net/seg6_hmac.h | 62 +++++
include/uapi/linux/ipv6.h | 3 +
include/uapi/linux/lwtunnel.h | 1 +
include/uapi/linux/seg6.h | 48 ++++
include/uapi/linux/seg6_genl.h | 32 +++
include/uapi/linux/seg6_hmac.h | 20 ++
include/uapi/linux/seg6_iptunnel.h | 41 +++
net/core/lwtunnel.c | 2 +
net/ipv6/Kconfig | 12 +
net/ipv6/Makefile | 3 +-
net/ipv6/addrconf.c | 28 ++
net/ipv6/exthdrs.c | 276 +++++++++++++++++++-
net/ipv6/ip6_output.c | 5 +-
net/ipv6/ip6_tunnel.c | 2 +-
net/ipv6/ipv6_sockglue.c | 2 +
net/ipv6/seg6.c | 403 ++++++++++++++++++++++++++++
net/ipv6/seg6_hmac.c | 432 +++++++++++++++++++++++++++++++
net/ipv6/seg6_iptunnel.c | 388 +++++++++++++++++++++++++++
27 files changed, 1840 insertions(+), 11 deletions(-)
create mode 100644 Documentation/networking/seg6-sysctl.txt
create mode 100644 include/linux/seg6.h
create mode 100644 include/linux/seg6_genl.h
create mode 100644 include/linux/seg6_hmac.h
create mode 100644 include/linux/seg6_iptunnel.h
create mode 100644 include/net/seg6.h
create mode 100644 include/net/seg6_hmac.h
create mode 100644 include/uapi/linux/seg6.h
create mode 100644 include/uapi/linux/seg6_genl.h
create mode 100644 include/uapi/linux/seg6_hmac.h
create mode 100644 include/uapi/linux/seg6_iptunnel.h
create mode 100644 net/ipv6/seg6.c
create mode 100644 net/ipv6/seg6_hmac.c
create mode 100644 net/ipv6/seg6_iptunnel.c
--
2.7.3
^ permalink raw reply [flat|nested] 15+ messages in thread
* [PATCH v2 1/9] ipv6: implement dataplane support for rthdr type 4 (Segment Routing Header)
2016-10-26 15:54 [PATCH v2 0/9] net: add support for IPv6 Segment Routing David Lebrun
@ 2016-10-26 15:54 ` David Lebrun
2016-10-28 2:50 ` Tom Herbert
2016-10-26 15:54 ` [PATCH v2 2/9] ipv6: sr: add code base for control plane support of SR-IPv6 David Lebrun
` (8 subsequent siblings)
9 siblings, 1 reply; 15+ messages in thread
From: David Lebrun @ 2016-10-26 15:54 UTC (permalink / raw)
To: netdev; +Cc: David Lebrun
Implement minimal support for processing of SR-enabled packets
as described in
https://tools.ietf.org/html/draft-ietf-6man-segment-routing-header-02.
This patch implements the following operations:
- Intermediate segment endpoint: incrementation of active segment and rerouting.
- Egress for SR-encapsulated packets: decapsulation of outer IPv6 header + SRH
and routing of inner packet.
- Cleanup flag support for SR-inlined packets: removal of SRH if we are the
penultimate segment endpoint.
A per-interface sysctl seg6_enabled is provided, to accept/deny SR-enabled
packets. Default is deny.
This patch does not provide support for HMAC-signed packets.
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
---
include/linux/ipv6.h | 1 +
include/linux/seg6.h | 6 ++
include/uapi/linux/ipv6.h | 2 +
include/uapi/linux/seg6.h | 48 ++++++++++++
net/ipv6/addrconf.c | 10 +++
net/ipv6/exthdrs.c | 183 ++++++++++++++++++++++++++++++++++++++++++++++
6 files changed, 250 insertions(+)
create mode 100644 include/linux/seg6.h
create mode 100644 include/uapi/linux/seg6.h
diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h
index 7e9a789..76830e6 100644
--- a/include/linux/ipv6.h
+++ b/include/linux/ipv6.h
@@ -64,6 +64,7 @@ struct ipv6_devconf {
} stable_secret;
__s32 use_oif_addrs_only;
__s32 keep_addr_on_down;
+ __s32 seg6_enabled;
struct ctl_table_header *sysctl_header;
};
diff --git a/include/linux/seg6.h b/include/linux/seg6.h
new file mode 100644
index 0000000..7a66d2b
--- /dev/null
+++ b/include/linux/seg6.h
@@ -0,0 +1,6 @@
+#ifndef _LINUX_SEG6_H
+#define _LINUX_SEG6_H
+
+#include <uapi/linux/seg6.h>
+
+#endif
diff --git a/include/uapi/linux/ipv6.h b/include/uapi/linux/ipv6.h
index 8c27723..7ff1d65 100644
--- a/include/uapi/linux/ipv6.h
+++ b/include/uapi/linux/ipv6.h
@@ -39,6 +39,7 @@ struct in6_ifreq {
#define IPV6_SRCRT_STRICT 0x01 /* Deprecated; will be removed */
#define IPV6_SRCRT_TYPE_0 0 /* Deprecated; will be removed */
#define IPV6_SRCRT_TYPE_2 2 /* IPv6 type 2 Routing Header */
+#define IPV6_SRCRT_TYPE_4 4 /* Segment Routing with IPv6 */
/*
* routing header
@@ -178,6 +179,7 @@ enum {
DEVCONF_DROP_UNSOLICITED_NA,
DEVCONF_KEEP_ADDR_ON_DOWN,
DEVCONF_RTR_SOLICIT_MAX_INTERVAL,
+ DEVCONF_SEG6_ENABLED,
DEVCONF_MAX
};
diff --git a/include/uapi/linux/seg6.h b/include/uapi/linux/seg6.h
new file mode 100644
index 0000000..7630e7d
--- /dev/null
+++ b/include/uapi/linux/seg6.h
@@ -0,0 +1,48 @@
+/*
+ * SR-IPv6 implementation
+ *
+ * Author:
+ * David Lebrun <david.lebrun@uclouvain.be>
+ *
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _UAPI_LINUX_SEG6_H
+#define _UAPI_LINUX_SEG6_H
+
+/*
+ * SRH
+ */
+struct ipv6_sr_hdr {
+ __u8 nexthdr;
+ __u8 hdrlen;
+ __u8 type;
+ __u8 segments_left;
+ __u8 first_segment;
+ __u8 flag_1;
+ __u8 flag_2;
+ __u8 reserved;
+
+ struct in6_addr segments[0];
+};
+
+#define SR6_FLAG1_CLEANUP (1 << 7)
+#define SR6_FLAG1_PROTECTED (1 << 6)
+#define SR6_FLAG1_OAM (1 << 5)
+#define SR6_FLAG1_ALERT (1 << 4)
+#define SR6_FLAG1_HMAC (1 << 3)
+
+#define SR6_TLV_INGRESS 1
+#define SR6_TLV_EGRESS 2
+#define SR6_TLV_OPAQUE 3
+#define SR6_TLV_PADDING 4
+#define SR6_TLV_HMAC 5
+
+#define sr_has_cleanup(srh) ((srh)->flag_1 & SR6_FLAG1_CLEANUP)
+#define sr_has_hmac(srh) ((srh)->flag_1 & SR6_FLAG1_HMAC)
+
+#endif
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index d8983e1..8d068ee 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -239,6 +239,7 @@ static struct ipv6_devconf ipv6_devconf __read_mostly = {
.use_oif_addrs_only = 0,
.ignore_routes_with_linkdown = 0,
.keep_addr_on_down = 0,
+ .seg6_enabled = 0,
};
static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
@@ -285,6 +286,7 @@ static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
.use_oif_addrs_only = 0,
.ignore_routes_with_linkdown = 0,
.keep_addr_on_down = 0,
+ .seg6_enabled = 0,
};
/* Check if a valid qdisc is available */
@@ -4965,6 +4967,7 @@ static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
+ array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
}
static inline size_t inet6_ifla6_size(void)
@@ -6057,6 +6060,13 @@ static const struct ctl_table addrconf_sysctl[] = {
},
{
+ .procname = "seg6_enabled",
+ .data = &ipv6_devconf.seg6_enabled,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
+ {
/* sentinel */
}
};
diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c
index 139ceb6..cf9f338 100644
--- a/net/ipv6/exthdrs.c
+++ b/net/ipv6/exthdrs.c
@@ -47,6 +47,7 @@
#if IS_ENABLED(CONFIG_IPV6_MIP6)
#include <net/xfrm.h>
#endif
+#include <linux/seg6.h>
#include <linux/uaccess.h>
@@ -286,6 +287,184 @@ static int ipv6_destopt_rcv(struct sk_buff *skb)
return -1;
}
+static inline void update_csum_diff4(struct sk_buff *skb, __be32 from,
+ __be32 to)
+{
+ __be32 diff[] = { ~from, to };
+
+ skb->csum = ~csum_partial((char *)diff, sizeof(diff), ~skb->csum);
+}
+
+static inline void update_csum_diff16(struct sk_buff *skb, __be32 *from,
+ __be32 *to)
+{
+ __be32 diff[] = {
+ ~from[0], ~from[1], ~from[2], ~from[3],
+ to[0], to[1], to[2], to[3],
+ };
+
+ skb->csum = ~csum_partial((char *)diff, sizeof(diff), ~skb->csum);
+}
+
+static void seg6_update_csum(struct sk_buff *skb)
+{
+ struct ipv6_sr_hdr *hdr;
+ struct in6_addr *addr;
+ __be32 from, to;
+
+ /* srh is at transport offset and seg_left is already decremented
+ * but daddr is not yet updated with next segment
+ */
+
+ hdr = (struct ipv6_sr_hdr *)skb_transport_header(skb);
+ addr = hdr->segments + hdr->segments_left;
+
+ hdr->segments_left++;
+ from = *(__be32 *)hdr;
+
+ hdr->segments_left--;
+ to = *(__be32 *)hdr;
+
+ /* update skb csum with diff resulting from seg_left decrement */
+
+ update_csum_diff4(skb, from, to);
+
+ /* compute csum diff between current and next segment and update */
+
+ update_csum_diff16(skb, (__be32 *)(&ipv6_hdr(skb)->daddr),
+ (__be32 *)addr);
+}
+
+static int ipv6_srh_rcv(struct sk_buff *skb)
+{
+ struct inet6_skb_parm *opt = IP6CB(skb);
+ struct net *net = dev_net(skb->dev);
+ struct ipv6_sr_hdr *hdr;
+ struct inet6_dev *idev;
+ struct in6_addr *addr;
+ int cleanup = 0;
+ int accept_seg6;
+
+ hdr = (struct ipv6_sr_hdr *)skb_transport_header(skb);
+
+ idev = __in6_dev_get(skb->dev);
+
+ accept_seg6 = net->ipv6.devconf_all->seg6_enabled;
+ if (accept_seg6 > idev->cnf.seg6_enabled)
+ accept_seg6 = idev->cnf.seg6_enabled;
+
+ if (!accept_seg6) {
+ kfree_skb(skb);
+ return -1;
+ }
+
+looped_back:
+ if (hdr->segments_left > 0) {
+ if (hdr->nexthdr != NEXTHDR_IPV6 && hdr->segments_left == 1 &&
+ sr_has_cleanup(hdr))
+ cleanup = 1;
+ } else {
+ if (hdr->nexthdr == NEXTHDR_IPV6) {
+ int offset = (hdr->hdrlen + 1) << 3;
+
+ skb_postpull_rcsum(skb, skb_network_header(skb),
+ skb_network_header_len(skb));
+
+ if (!pskb_pull(skb, offset)) {
+ kfree_skb(skb);
+ return -1;
+ }
+ skb_postpull_rcsum(skb, skb_transport_header(skb),
+ offset);
+
+ skb_reset_network_header(skb);
+ skb_reset_transport_header(skb);
+ skb->encapsulation = 0;
+
+ __skb_tunnel_rx(skb, skb->dev, net);
+
+ netif_rx(skb);
+ return -1;
+ }
+
+ opt->srcrt = skb_network_header_len(skb);
+ opt->lastopt = opt->srcrt;
+ skb->transport_header += (hdr->hdrlen + 1) << 3;
+ opt->nhoff = (&hdr->nexthdr) - skb_network_header(skb);
+
+ return 1;
+ }
+
+ if (skb_cloned(skb)) {
+ if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) {
+ __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
+ IPSTATS_MIB_OUTDISCARDS);
+ kfree_skb(skb);
+ return -1;
+ }
+ }
+
+ hdr = (struct ipv6_sr_hdr *)skb_transport_header(skb);
+
+ hdr->segments_left--;
+ addr = hdr->segments + hdr->segments_left;
+
+ skb_push(skb, sizeof(struct ipv6hdr));
+
+ if (skb->ip_summed == CHECKSUM_COMPLETE)
+ seg6_update_csum(skb);
+
+ ipv6_hdr(skb)->daddr = *addr;
+
+ if (cleanup) {
+ int srhlen = (hdr->hdrlen + 1) << 3;
+ int nh = hdr->nexthdr;
+
+ skb_pull_rcsum(skb, sizeof(struct ipv6hdr) + srhlen);
+ memmove(skb_network_header(skb) + srhlen,
+ skb_network_header(skb),
+ (unsigned char *)hdr - skb_network_header(skb));
+ skb->network_header += srhlen;
+ ipv6_hdr(skb)->nexthdr = nh;
+ ipv6_hdr(skb)->payload_len = htons(skb->len -
+ sizeof(struct ipv6hdr));
+ skb_push_rcsum(skb, sizeof(struct ipv6hdr));
+ }
+
+ skb_dst_drop(skb);
+
+ ip6_route_input(skb);
+
+ if (skb_dst(skb)->error) {
+ dst_input(skb);
+ return -1;
+ }
+
+ if (skb_dst(skb)->dev->flags & IFF_LOOPBACK) {
+ if (ipv6_hdr(skb)->hop_limit <= 1) {
+ __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
+ IPSTATS_MIB_INHDRERRORS);
+ icmpv6_send(skb, ICMPV6_TIME_EXCEED,
+ ICMPV6_EXC_HOPLIMIT, 0);
+ kfree_skb(skb);
+ return -1;
+ }
+ ipv6_hdr(skb)->hop_limit--;
+
+ /* be sure that srh is still present before reinjecting */
+ if (!cleanup) {
+ skb_pull(skb, sizeof(struct ipv6hdr));
+ goto looped_back;
+ }
+ skb_set_transport_header(skb, sizeof(struct ipv6hdr));
+ IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr);
+ }
+
+ dst_input(skb);
+
+ return -1;
+}
+
/********************************
Routing header.
********************************/
@@ -326,6 +505,10 @@ static int ipv6_rthdr_rcv(struct sk_buff *skb)
return -1;
}
+ /* segment routing */
+ if (hdr->type == IPV6_SRCRT_TYPE_4)
+ return ipv6_srh_rcv(skb);
+
looped_back:
if (hdr->segments_left == 0) {
switch (hdr->type) {
--
2.7.3
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v2 2/9] ipv6: sr: add code base for control plane support of SR-IPv6
2016-10-26 15:54 [PATCH v2 0/9] net: add support for IPv6 Segment Routing David Lebrun
2016-10-26 15:54 ` [PATCH v2 1/9] ipv6: implement dataplane support for rthdr type 4 (Segment Routing Header) David Lebrun
@ 2016-10-26 15:54 ` David Lebrun
2016-10-28 2:52 ` Tom Herbert
2016-10-26 15:54 ` [PATCH v2 3/9] ipv6: sr: add support for SRH encapsulation and injection with lwtunnels David Lebrun
` (7 subsequent siblings)
9 siblings, 1 reply; 15+ messages in thread
From: David Lebrun @ 2016-10-26 15:54 UTC (permalink / raw)
To: netdev; +Cc: David Lebrun
This patch adds the necessary hooks and structures to provide support
for SR-IPv6 control plane, essentially the Generic Netlink commands
that will be used for userspace control over the Segment Routing
kernel structures.
The genetlink commands provide control over two different structures:
tunnel source and HMAC data. The tunnel source is the source address
that will be used by default when encapsulating packets into an
outer IPv6 header + SRH. If the tunnel source is set to :: then an
address of the outgoing interface will be selected as the source.
The HMAC commands currently just return ENOTSUPP and will be implemented
in a future patch.
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
---
include/linux/seg6_genl.h | 6 ++
include/net/netns/ipv6.h | 1 +
include/net/seg6.h | 30 ++++++
include/uapi/linux/seg6_genl.h | 32 ++++++
net/ipv6/Makefile | 2 +-
net/ipv6/seg6.c | 214 +++++++++++++++++++++++++++++++++++++++++
6 files changed, 284 insertions(+), 1 deletion(-)
create mode 100644 include/linux/seg6_genl.h
create mode 100644 include/net/seg6.h
create mode 100644 include/uapi/linux/seg6_genl.h
create mode 100644 net/ipv6/seg6.c
diff --git a/include/linux/seg6_genl.h b/include/linux/seg6_genl.h
new file mode 100644
index 0000000..d6c3fb4f
--- /dev/null
+++ b/include/linux/seg6_genl.h
@@ -0,0 +1,6 @@
+#ifndef _LINUX_SEG6_GENL_H
+#define _LINUX_SEG6_GENL_H
+
+#include <uapi/linux/seg6_genl.h>
+
+#endif
diff --git a/include/net/netns/ipv6.h b/include/net/netns/ipv6.h
index 10d0848..de7745e 100644
--- a/include/net/netns/ipv6.h
+++ b/include/net/netns/ipv6.h
@@ -85,6 +85,7 @@ struct netns_ipv6 {
#endif
atomic_t dev_addr_genid;
atomic_t fib6_sernum;
+ struct seg6_pernet_data *seg6_data;
};
#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
diff --git a/include/net/seg6.h b/include/net/seg6.h
new file mode 100644
index 0000000..a9d9a9b
--- /dev/null
+++ b/include/net/seg6.h
@@ -0,0 +1,30 @@
+/*
+ * SR-IPv6 implementation
+ *
+ * Author:
+ * David Lebrun <david.lebrun@uclouvain.be>
+ *
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _NET_SEG6_H
+#define _NET_SEG6_H
+
+#include <linux/net.h>
+#include <linux/ipv6.h>
+
+struct seg6_pernet_data {
+ struct mutex lock;
+ struct in6_addr __rcu *tun_src;
+};
+
+static inline struct seg6_pernet_data *seg6_pernet(struct net *net)
+{
+ return net->ipv6.seg6_data;
+}
+
+#endif
diff --git a/include/uapi/linux/seg6_genl.h b/include/uapi/linux/seg6_genl.h
new file mode 100644
index 0000000..fcf1c60
--- /dev/null
+++ b/include/uapi/linux/seg6_genl.h
@@ -0,0 +1,32 @@
+#ifndef _UAPI_LINUX_SEG6_GENL_H
+#define _UAPI_LINUX_SEG6_GENL_H
+
+#define SEG6_GENL_NAME "SEG6"
+#define SEG6_GENL_VERSION 0x1
+
+enum {
+ SEG6_ATTR_UNSPEC,
+ SEG6_ATTR_DST,
+ SEG6_ATTR_DSTLEN,
+ SEG6_ATTR_HMACKEYID,
+ SEG6_ATTR_SECRET,
+ SEG6_ATTR_SECRETLEN,
+ SEG6_ATTR_ALGID,
+ SEG6_ATTR_HMACINFO,
+ __SEG6_ATTR_MAX,
+};
+
+#define SEG6_ATTR_MAX (__SEG6_ATTR_MAX - 1)
+
+enum {
+ SEG6_CMD_UNSPEC,
+ SEG6_CMD_SETHMAC,
+ SEG6_CMD_DUMPHMAC,
+ SEG6_CMD_SET_TUNSRC,
+ SEG6_CMD_GET_TUNSRC,
+ __SEG6_CMD_MAX,
+};
+
+#define SEG6_CMD_MAX (__SEG6_CMD_MAX - 1)
+
+#endif
diff --git a/net/ipv6/Makefile b/net/ipv6/Makefile
index c174ccb..29a77d3 100644
--- a/net/ipv6/Makefile
+++ b/net/ipv6/Makefile
@@ -45,7 +45,7 @@ obj-$(CONFIG_IPV6_TUNNEL) += ip6_tunnel.o
obj-$(CONFIG_IPV6_GRE) += ip6_gre.o
obj-$(CONFIG_IPV6_FOU) += fou6.o
-obj-y += addrconf_core.o exthdrs_core.o ip6_checksum.o ip6_icmp.o
+obj-y += addrconf_core.o exthdrs_core.o ip6_checksum.o ip6_icmp.o seg6.o
obj-$(CONFIG_INET) += output_core.o protocol.o $(ipv6-offload)
obj-$(subst m,y,$(CONFIG_IPV6)) += inet6_hashtables.o
diff --git a/net/ipv6/seg6.c b/net/ipv6/seg6.c
new file mode 100644
index 0000000..24111662
--- /dev/null
+++ b/net/ipv6/seg6.c
@@ -0,0 +1,214 @@
+/*
+ * SR-IPv6 implementation
+ *
+ * Author:
+ * David Lebrun <david.lebrun@uclouvain.be>
+ *
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/net.h>
+#include <linux/in6.h>
+#include <linux/slab.h>
+
+#include <net/ipv6.h>
+#include <net/protocol.h>
+
+#include <net/seg6.h>
+#include <net/genetlink.h>
+#include <linux/seg6.h>
+#include <linux/seg6_genl.h>
+
+static const struct nla_policy seg6_genl_policy[SEG6_ATTR_MAX + 1] = {
+ [SEG6_ATTR_DST] = { .type = NLA_BINARY,
+ .len = sizeof(struct in6_addr) },
+ [SEG6_ATTR_DSTLEN] = { .type = NLA_S32, },
+ [SEG6_ATTR_HMACKEYID] = { .type = NLA_U32, },
+ [SEG6_ATTR_SECRET] = { .type = NLA_BINARY, },
+ [SEG6_ATTR_SECRETLEN] = { .type = NLA_U8, },
+ [SEG6_ATTR_ALGID] = { .type = NLA_U8, },
+ [SEG6_ATTR_HMACINFO] = { .type = NLA_NESTED, },
+};
+
+static struct genl_family seg6_genl_family = {
+ .id = GENL_ID_GENERATE,
+ .hdrsize = 0,
+ .name = SEG6_GENL_NAME,
+ .version = SEG6_GENL_VERSION,
+ .maxattr = SEG6_ATTR_MAX,
+ .netnsok = true,
+};
+
+static int seg6_genl_sethmac(struct sk_buff *skb, struct genl_info *info)
+{
+ return -ENOTSUPP;
+}
+
+static int seg6_genl_set_tunsrc(struct sk_buff *skb, struct genl_info *info)
+{
+ struct net *net = genl_info_net(info);
+ struct in6_addr *val, *t_old, *t_new;
+ struct seg6_pernet_data *sdata;
+
+ sdata = seg6_pernet(net);
+
+ if (!info->attrs[SEG6_ATTR_DST])
+ return -EINVAL;
+
+ val = nla_data(info->attrs[SEG6_ATTR_DST]);
+ t_new = kmemdup(val, sizeof(*val), GFP_KERNEL);
+
+ mutex_lock(&sdata->lock);
+
+ t_old = sdata->tun_src;
+ rcu_assign_pointer(sdata->tun_src, t_new);
+
+ mutex_unlock(&sdata->lock);
+
+ synchronize_net();
+ kfree(t_old);
+
+ return 0;
+}
+
+static int seg6_genl_get_tunsrc(struct sk_buff *skb, struct genl_info *info)
+{
+ struct net *net = genl_info_net(info);
+ struct in6_addr *tun_src;
+ struct sk_buff *msg;
+ void *hdr;
+
+ msg = genlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+ if (!msg)
+ return -ENOMEM;
+
+ hdr = genlmsg_put(msg, info->snd_portid, info->snd_seq,
+ &seg6_genl_family, 0, SEG6_CMD_GET_TUNSRC);
+ if (!hdr)
+ goto free_msg;
+
+ rcu_read_lock();
+ tun_src = rcu_dereference(seg6_pernet(net)->tun_src);
+
+ if (nla_put(msg, SEG6_ATTR_DST, sizeof(struct in6_addr), tun_src))
+ goto nla_put_failure;
+
+ rcu_read_unlock();
+
+ genlmsg_end(msg, hdr);
+ genlmsg_reply(msg, info);
+
+ return 0;
+
+nla_put_failure:
+ rcu_read_unlock();
+ genlmsg_cancel(msg, hdr);
+free_msg:
+ nlmsg_free(msg);
+ return -ENOMEM;
+}
+
+static int seg6_genl_dumphmac(struct sk_buff *skb, struct netlink_callback *cb)
+{
+ return -ENOTSUPP;
+}
+
+static const struct genl_ops seg6_genl_ops[] = {
+ {
+ .cmd = SEG6_CMD_SETHMAC,
+ .doit = seg6_genl_sethmac,
+ .policy = seg6_genl_policy,
+ .flags = GENL_ADMIN_PERM,
+ },
+ {
+ .cmd = SEG6_CMD_DUMPHMAC,
+ .dumpit = seg6_genl_dumphmac,
+ .policy = seg6_genl_policy,
+ .flags = GENL_ADMIN_PERM,
+ },
+ {
+ .cmd = SEG6_CMD_SET_TUNSRC,
+ .doit = seg6_genl_set_tunsrc,
+ .policy = seg6_genl_policy,
+ .flags = GENL_ADMIN_PERM,
+ },
+ {
+ .cmd = SEG6_CMD_GET_TUNSRC,
+ .doit = seg6_genl_get_tunsrc,
+ .policy = seg6_genl_policy,
+ .flags = GENL_ADMIN_PERM,
+ },
+};
+
+static int __net_init seg6_net_init(struct net *net)
+{
+ struct seg6_pernet_data *sdata;
+
+ sdata = kzalloc(sizeof(*sdata), GFP_KERNEL);
+ if (!sdata)
+ return -ENOMEM;
+
+ mutex_init(&sdata->lock);
+
+ sdata->tun_src = kzalloc(sizeof(*sdata->tun_src), GFP_KERNEL);
+ if (!sdata->tun_src) {
+ kfree(sdata);
+ return -ENOMEM;
+ }
+
+ net->ipv6.seg6_data = sdata;
+
+ return 0;
+}
+
+static void __net_exit seg6_net_exit(struct net *net)
+{
+ struct seg6_pernet_data *sdata = seg6_pernet(net);
+
+ kfree(sdata->tun_src);
+ kfree(sdata);
+}
+
+static struct pernet_operations ip6_segments_ops = {
+ .init = seg6_net_init,
+ .exit = seg6_net_exit,
+};
+
+static int __init seg6_init(void)
+{
+ int err = -ENOMEM;
+
+ err = genl_register_family_with_ops(&seg6_genl_family, seg6_genl_ops);
+ if (err)
+ goto out;
+
+ err = register_pernet_subsys(&ip6_segments_ops);
+ if (err)
+ goto out_unregister_genl;
+
+ pr_info("Segment Routing with IPv6\n");
+
+out:
+ return err;
+out_unregister_genl:
+ genl_unregister_family(&seg6_genl_family);
+ goto out;
+}
+module_init(seg6_init);
+
+static void __exit seg6_exit(void)
+{
+ unregister_pernet_subsys(&ip6_segments_ops);
+ genl_unregister_family(&seg6_genl_family);
+}
+module_exit(seg6_exit);
+
+MODULE_DESCRIPTION("Segment Routing with IPv6");
+MODULE_LICENSE("GPL v2");
--
2.7.3
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v2 3/9] ipv6: sr: add support for SRH encapsulation and injection with lwtunnels
2016-10-26 15:54 [PATCH v2 0/9] net: add support for IPv6 Segment Routing David Lebrun
2016-10-26 15:54 ` [PATCH v2 1/9] ipv6: implement dataplane support for rthdr type 4 (Segment Routing Header) David Lebrun
2016-10-26 15:54 ` [PATCH v2 2/9] ipv6: sr: add code base for control plane support of SR-IPv6 David Lebrun
@ 2016-10-26 15:54 ` David Lebrun
2016-10-28 2:56 ` Tom Herbert
2016-10-26 15:54 ` [PATCH v2 4/9] ipv6: sr: add core files for SR HMAC support David Lebrun
` (6 subsequent siblings)
9 siblings, 1 reply; 15+ messages in thread
From: David Lebrun @ 2016-10-26 15:54 UTC (permalink / raw)
To: netdev; +Cc: David Lebrun
This patch creates a new type of interfaceless lightweight tunnel (SEG6),
enabling the encapsulation and injection of SRH within locally emitted
packets and forwarded packets.
>From a configuration viewpoint, a seg6 tunnel would be configured as follows:
ip -6 ro ad fc00::1/128 encap seg6 mode encap segs fc42::1,fc42::2,fc42::3 dev eth0
Any packet whose destination address is fc00::1 would thus be encapsulated
within an outer IPv6 header containing the SRH with three segments, and would
actually be routed to the first segment of the list. If `mode inline' was
specified instead of `mode encap', then the SRH would be directly inserted
after the IPv6 header without outer encapsulation.
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
---
include/linux/seg6_iptunnel.h | 6 +
include/net/seg6.h | 1 +
include/uapi/linux/lwtunnel.h | 1 +
include/uapi/linux/seg6_iptunnel.h | 41 ++++
net/core/lwtunnel.c | 2 +
net/ipv6/Makefile | 2 +-
net/ipv6/seg6_iptunnel.c | 370 +++++++++++++++++++++++++++++++++++++
7 files changed, 422 insertions(+), 1 deletion(-)
create mode 100644 include/linux/seg6_iptunnel.h
create mode 100644 include/uapi/linux/seg6_iptunnel.h
create mode 100644 net/ipv6/seg6_iptunnel.c
diff --git a/include/linux/seg6_iptunnel.h b/include/linux/seg6_iptunnel.h
new file mode 100644
index 0000000..5377cf6
--- /dev/null
+++ b/include/linux/seg6_iptunnel.h
@@ -0,0 +1,6 @@
+#ifndef _LINUX_SEG6_IPTUNNEL_H
+#define _LINUX_SEG6_IPTUNNEL_H
+
+#include <uapi/linux/seg6_iptunnel.h>
+
+#endif
diff --git a/include/net/seg6.h b/include/net/seg6.h
index a9d9a9b..53d3bdb 100644
--- a/include/net/seg6.h
+++ b/include/net/seg6.h
@@ -16,6 +16,7 @@
#include <linux/net.h>
#include <linux/ipv6.h>
+#include <net/lwtunnel.h>
struct seg6_pernet_data {
struct mutex lock;
diff --git a/include/uapi/linux/lwtunnel.h b/include/uapi/linux/lwtunnel.h
index a478fe8..453cc62 100644
--- a/include/uapi/linux/lwtunnel.h
+++ b/include/uapi/linux/lwtunnel.h
@@ -9,6 +9,7 @@ enum lwtunnel_encap_types {
LWTUNNEL_ENCAP_IP,
LWTUNNEL_ENCAP_ILA,
LWTUNNEL_ENCAP_IP6,
+ LWTUNNEL_ENCAP_SEG6,
__LWTUNNEL_ENCAP_MAX,
};
diff --git a/include/uapi/linux/seg6_iptunnel.h b/include/uapi/linux/seg6_iptunnel.h
new file mode 100644
index 0000000..da5524a
--- /dev/null
+++ b/include/uapi/linux/seg6_iptunnel.h
@@ -0,0 +1,41 @@
+/*
+ * SR-IPv6 implementation
+ *
+ * Author:
+ * David Lebrun <david.lebrun@uclouvain.be>
+ *
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _UAPI_LINUX_SEG6_IPTUNNEL_H
+#define _UAPI_LINUX_SEG6_IPTUNNEL_H
+
+enum {
+ SEG6_IPTUNNEL_UNSPEC,
+ SEG6_IPTUNNEL_SRH,
+ __SEG6_IPTUNNEL_MAX,
+};
+#define SEG6_IPTUNNEL_MAX (__SEG6_IPTUNNEL_MAX - 1)
+
+struct seg6_iptunnel_encap {
+ int flags;
+ struct ipv6_sr_hdr srh[0];
+};
+
+#define SEG6_IPTUN_ENCAP_SIZE(x) ((sizeof(*x)) + (((x)->srh->hdrlen + 1) << 3))
+
+#define SEG6_IPTUN_FLAG_ENCAP 0x1
+
+static inline size_t seg6_lwt_headroom(struct seg6_iptunnel_encap *tuninfo)
+{
+ int encap = !!(tuninfo->flags & SEG6_IPTUN_FLAG_ENCAP);
+
+ return ((tuninfo->srh->hdrlen + 1) << 3) +
+ (encap * sizeof(struct ipv6hdr));
+}
+
+#endif
diff --git a/net/core/lwtunnel.c b/net/core/lwtunnel.c
index 88fd642..03976e9 100644
--- a/net/core/lwtunnel.c
+++ b/net/core/lwtunnel.c
@@ -39,6 +39,8 @@ static const char *lwtunnel_encap_str(enum lwtunnel_encap_types encap_type)
return "MPLS";
case LWTUNNEL_ENCAP_ILA:
return "ILA";
+ case LWTUNNEL_ENCAP_SEG6:
+ return "SEG6";
case LWTUNNEL_ENCAP_IP6:
case LWTUNNEL_ENCAP_IP:
case LWTUNNEL_ENCAP_NONE:
diff --git a/net/ipv6/Makefile b/net/ipv6/Makefile
index 29a77d3..4bd1e73 100644
--- a/net/ipv6/Makefile
+++ b/net/ipv6/Makefile
@@ -45,7 +45,7 @@ obj-$(CONFIG_IPV6_TUNNEL) += ip6_tunnel.o
obj-$(CONFIG_IPV6_GRE) += ip6_gre.o
obj-$(CONFIG_IPV6_FOU) += fou6.o
-obj-y += addrconf_core.o exthdrs_core.o ip6_checksum.o ip6_icmp.o seg6.o
+obj-y += addrconf_core.o exthdrs_core.o ip6_checksum.o ip6_icmp.o seg6.o seg6_iptunnel.o
obj-$(CONFIG_INET) += output_core.o protocol.o $(ipv6-offload)
obj-$(subst m,y,$(CONFIG_IPV6)) += inet6_hashtables.o
diff --git a/net/ipv6/seg6_iptunnel.c b/net/ipv6/seg6_iptunnel.c
new file mode 100644
index 0000000..caae8ab
--- /dev/null
+++ b/net/ipv6/seg6_iptunnel.c
@@ -0,0 +1,370 @@
+/*
+ * SR-IPv6 implementation
+ *
+ * Author:
+ * David Lebrun <david.lebrun@uclouvain.be>
+ *
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/types.h>
+#include <linux/skbuff.h>
+#include <linux/net.h>
+#include <linux/module.h>
+#include <net/ip.h>
+#include <net/lwtunnel.h>
+#include <net/netevent.h>
+#include <net/netns/generic.h>
+#include <net/ip6_fib.h>
+#include <net/route.h>
+#include <net/seg6.h>
+#include <linux/seg6.h>
+#include <linux/seg6_iptunnel.h>
+#include <net/addrconf.h>
+#include <net/ip6_route.h>
+#include <net/dst_cache.h>
+
+struct seg6_lwt {
+ struct dst_cache cache;
+ struct seg6_iptunnel_encap tuninfo[0];
+};
+
+static inline struct seg6_lwt *seg6_lwt_lwtunnel(struct lwtunnel_state *lwt)
+{
+ return (struct seg6_lwt *)lwt->data;
+}
+
+static inline struct seg6_iptunnel_encap *
+seg6_encap_lwtunnel(struct lwtunnel_state *lwt)
+{
+ return seg6_lwt_lwtunnel(lwt)->tuninfo;
+}
+
+static const struct nla_policy seg6_iptunnel_policy[SEG6_IPTUNNEL_MAX + 1] = {
+ [SEG6_IPTUNNEL_SRH] = { .type = NLA_BINARY },
+};
+
+int nla_put_srh(struct sk_buff *skb, int attrtype,
+ struct seg6_iptunnel_encap *tuninfo)
+{
+ struct seg6_iptunnel_encap *data;
+ struct nlattr *nla;
+ int len;
+
+ len = SEG6_IPTUN_ENCAP_SIZE(tuninfo);
+
+ nla = nla_reserve(skb, attrtype, len);
+ if (!nla)
+ return -EMSGSIZE;
+
+ data = nla_data(nla);
+ memcpy(data, tuninfo, len);
+
+ return 0;
+}
+
+static void set_tun_src(struct net *net, struct net_device *dev,
+ struct in6_addr *daddr, struct in6_addr *saddr)
+{
+ struct seg6_pernet_data *sdata = seg6_pernet(net);
+ struct in6_addr *tun_src;
+
+ rcu_read_lock();
+
+ tun_src = rcu_dereference(sdata->tun_src);
+
+ if (!ipv6_addr_any(tun_src)) {
+ memcpy(saddr, tun_src, sizeof(struct in6_addr));
+ } else {
+ ipv6_dev_get_saddr(net, dev, daddr, IPV6_PREFER_SRC_PUBLIC,
+ saddr);
+ }
+
+ rcu_read_unlock();
+}
+
+/* encapsulate an IPv6 packet within an outer IPv6 header with a given SRH */
+static int seg6_do_srh_encap(struct sk_buff *skb, struct ipv6_sr_hdr *osrh)
+{
+ struct net *net = dev_net(skb_dst(skb)->dev);
+ struct ipv6hdr *hdr, *inner_hdr;
+ struct ipv6_sr_hdr *isrh;
+ int hdrlen, tot_len, err;
+
+ hdrlen = (osrh->hdrlen + 1) << 3;
+ tot_len = hdrlen + sizeof(*hdr);
+
+ err = pskb_expand_head(skb, tot_len, 0, GFP_ATOMIC);
+ if (unlikely(err))
+ return err;
+
+ inner_hdr = ipv6_hdr(skb);
+
+ skb_push(skb, tot_len);
+ skb_reset_network_header(skb);
+ skb_mac_header_rebuild(skb);
+ hdr = ipv6_hdr(skb);
+
+ /* inherit tc, flowlabel and hlim
+ * hlim will be decremented in ip6_forward() afterwards and
+ * decapsulation will overwrite inner hlim with outer hlim
+ */
+ ip6_flow_hdr(hdr, ip6_tclass(ip6_flowinfo(inner_hdr)),
+ ip6_flowlabel(inner_hdr));
+ hdr->hop_limit = inner_hdr->hop_limit;
+ hdr->nexthdr = NEXTHDR_ROUTING;
+
+ isrh = (void *)hdr + sizeof(*hdr);
+ memcpy(isrh, osrh, hdrlen);
+
+ isrh->nexthdr = NEXTHDR_IPV6;
+
+ hdr->daddr = isrh->segments[isrh->first_segment];
+ set_tun_src(net, skb->dev, &hdr->daddr, &hdr->saddr);
+
+ skb_postpush_rcsum(skb, hdr, tot_len);
+
+ return 0;
+}
+
+/* insert an SRH within an IPv6 packet, just after the IPv6 header */
+static int seg6_do_srh_inline(struct sk_buff *skb, struct ipv6_sr_hdr *osrh)
+{
+ struct ipv6hdr *hdr, *oldhdr;
+ struct ipv6_sr_hdr *isrh;
+ int hdrlen, err;
+
+ hdrlen = (osrh->hdrlen + 1) << 3;
+
+ err = pskb_expand_head(skb, hdrlen, 0, GFP_ATOMIC);
+ if (unlikely(err))
+ return err;
+
+ oldhdr = ipv6_hdr(skb);
+
+ skb_pull(skb, sizeof(struct ipv6hdr));
+ skb_postpull_rcsum(skb, skb_network_header(skb),
+ sizeof(struct ipv6hdr));
+
+ skb_push(skb, sizeof(struct ipv6hdr) + hdrlen);
+ skb_reset_network_header(skb);
+ skb_mac_header_rebuild(skb);
+
+ hdr = ipv6_hdr(skb);
+
+ memmove(hdr, oldhdr, sizeof(*hdr));
+
+ isrh = (void *)hdr + sizeof(*hdr);
+ memcpy(isrh, osrh, hdrlen);
+
+ isrh->nexthdr = hdr->nexthdr;
+ hdr->nexthdr = NEXTHDR_ROUTING;
+
+ isrh->segments[0] = hdr->daddr;
+ hdr->daddr = isrh->segments[isrh->first_segment];
+
+ skb_postpush_rcsum(skb, hdr, sizeof(struct ipv6hdr) + hdrlen);
+
+ return 0;
+}
+
+static int seg6_do_srh(struct sk_buff *skb)
+{
+ struct dst_entry *dst = skb_dst(skb);
+ struct seg6_iptunnel_encap *tinfo;
+ int err = 0;
+
+ tinfo = seg6_encap_lwtunnel(dst->lwtstate);
+
+ if (likely(!skb->encapsulation)) {
+ skb_reset_inner_headers(skb);
+ skb->encapsulation = 1;
+ }
+
+ if (tinfo->flags & SEG6_IPTUN_FLAG_ENCAP) {
+ err = seg6_do_srh_encap(skb, tinfo->srh);
+ } else {
+ err = seg6_do_srh_inline(skb, tinfo->srh);
+ skb_reset_inner_headers(skb);
+ }
+
+ if (err)
+ return err;
+
+ ipv6_hdr(skb)->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
+ skb_set_transport_header(skb, sizeof(struct ipv6hdr));
+
+ skb_set_inner_protocol(skb, skb->protocol);
+
+ return 0;
+}
+
+int seg6_input(struct sk_buff *skb)
+{
+ int err;
+
+ err = seg6_do_srh(skb);
+ if (unlikely(err)) {
+ kfree_skb(skb);
+ return err;
+ }
+
+ skb_dst_drop(skb);
+ ip6_route_input(skb);
+
+ return dst_input(skb);
+}
+
+int seg6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
+{
+ struct dst_entry *orig_dst = skb_dst(skb);
+ struct seg6_lwt *slwt;
+ struct dst_entry *dst;
+ int err = -EINVAL;
+
+ err = seg6_do_srh(skb);
+ if (unlikely(err))
+ goto drop;
+
+ slwt = seg6_lwt_lwtunnel(orig_dst->lwtstate);
+
+ dst = dst_cache_get(&slwt->cache);
+ if (unlikely(!dst)) {
+ struct ipv6hdr *hdr = ipv6_hdr(skb);
+ struct flowi6 fl6;
+
+ fl6.daddr = hdr->daddr;
+ fl6.saddr = hdr->saddr;
+ fl6.flowlabel = ip6_flowinfo(hdr);
+ fl6.flowi6_mark = skb->mark;
+ fl6.flowi6_proto = hdr->nexthdr;
+
+ dst = ip6_route_output(net, NULL, &fl6);
+ if (dst->error) {
+ err = dst->error;
+ dst_release(dst);
+ goto drop;
+ }
+
+ dst_cache_set_ip6(&slwt->cache, dst, &fl6.saddr);
+ }
+
+ skb_dst_drop(skb);
+ skb_dst_set(skb, dst);
+
+ return dst_output(net, sk, skb);
+drop:
+ kfree_skb(skb);
+ return err;
+}
+
+static int seg6_build_state(struct net_device *dev, struct nlattr *nla,
+ unsigned int family, const void *cfg,
+ struct lwtunnel_state **ts)
+{
+ struct nlattr *tb[SEG6_IPTUNNEL_MAX + 1];
+ struct seg6_iptunnel_encap *tuninfo;
+ struct lwtunnel_state *newts;
+ struct seg6_lwt *slwt;
+ int tuninfo_len;
+ int err;
+
+ err = nla_parse_nested(tb, SEG6_IPTUNNEL_MAX, nla,
+ seg6_iptunnel_policy);
+
+ if (err < 0)
+ return err;
+
+ if (!tb[SEG6_IPTUNNEL_SRH])
+ return -EINVAL;
+
+ tuninfo = nla_data(tb[SEG6_IPTUNNEL_SRH]);
+ tuninfo_len = SEG6_IPTUN_ENCAP_SIZE(tuninfo);
+
+ newts = lwtunnel_state_alloc(tuninfo_len + sizeof(*slwt));
+ if (!newts)
+ return -ENOMEM;
+
+ slwt = seg6_lwt_lwtunnel(newts);
+
+ err = dst_cache_init(&slwt->cache, GFP_KERNEL);
+ if (err) {
+ kfree(newts);
+ return err;
+ }
+
+ memcpy(&slwt->tuninfo, tuninfo, tuninfo_len);
+
+ newts->type = LWTUNNEL_ENCAP_SEG6;
+ newts->flags |= LWTUNNEL_STATE_OUTPUT_REDIRECT |
+ LWTUNNEL_STATE_INPUT_REDIRECT;
+ newts->headroom = seg6_lwt_headroom(tuninfo);
+
+ *ts = newts;
+
+ return 0;
+}
+
+static void seg6_destroy_state(struct lwtunnel_state *lwt)
+{
+ dst_cache_destroy(&seg6_lwt_lwtunnel(lwt)->cache);
+}
+
+static int seg6_fill_encap_info(struct sk_buff *skb,
+ struct lwtunnel_state *lwtstate)
+{
+ struct seg6_iptunnel_encap *tuninfo = seg6_encap_lwtunnel(lwtstate);
+
+ if (nla_put_srh(skb, SEG6_IPTUNNEL_SRH, tuninfo))
+ return -EMSGSIZE;
+
+ return 0;
+}
+
+static int seg6_encap_nlsize(struct lwtunnel_state *lwtstate)
+{
+ struct seg6_iptunnel_encap *tuninfo = seg6_encap_lwtunnel(lwtstate);
+
+ return nla_total_size(SEG6_IPTUN_ENCAP_SIZE(tuninfo));
+}
+
+static int seg6_encap_cmp(struct lwtunnel_state *a, struct lwtunnel_state *b)
+{
+ struct seg6_iptunnel_encap *a_hdr = seg6_encap_lwtunnel(a);
+ struct seg6_iptunnel_encap *b_hdr = seg6_encap_lwtunnel(b);
+ int len = SEG6_IPTUN_ENCAP_SIZE(a_hdr);
+
+ if (len != SEG6_IPTUN_ENCAP_SIZE(b_hdr))
+ return 1;
+
+ return memcmp(a_hdr, b_hdr, len);
+}
+
+static const struct lwtunnel_encap_ops seg6_iptun_ops = {
+ .build_state = seg6_build_state,
+ .destroy_state = seg6_destroy_state,
+ .output = seg6_output,
+ .input = seg6_input,
+ .fill_encap = seg6_fill_encap_info,
+ .get_encap_size = seg6_encap_nlsize,
+ .cmp_encap = seg6_encap_cmp,
+};
+
+static int __init seg6_iptunnel_init(void)
+{
+ return lwtunnel_encap_add_ops(&seg6_iptun_ops, LWTUNNEL_ENCAP_SEG6);
+}
+module_init(seg6_iptunnel_init);
+
+static void __exit seg6_iptunnel_exit(void)
+{
+ lwtunnel_encap_del_ops(&seg6_iptun_ops, LWTUNNEL_ENCAP_SEG6);
+}
+module_exit(seg6_iptunnel_exit);
+
+MODULE_DESCRIPTION("Segment Routing with IPv6 IP Tunnels");
+MODULE_LICENSE("GPL v2");
--
2.7.3
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v2 4/9] ipv6: sr: add core files for SR HMAC support
2016-10-26 15:54 [PATCH v2 0/9] net: add support for IPv6 Segment Routing David Lebrun
` (2 preceding siblings ...)
2016-10-26 15:54 ` [PATCH v2 3/9] ipv6: sr: add support for SRH encapsulation and injection with lwtunnels David Lebrun
@ 2016-10-26 15:54 ` David Lebrun
2016-10-28 3:05 ` Tom Herbert
2016-10-26 15:56 ` [PATCH v2 5/9] ipv6: sr: implement API to control SR HMAC structure David Lebrun
` (5 subsequent siblings)
9 siblings, 1 reply; 15+ messages in thread
From: David Lebrun @ 2016-10-26 15:54 UTC (permalink / raw)
To: netdev; +Cc: David Lebrun
This patch adds the necessary functions to compute and check the HMAC signature
of an SR-enabled packet. Two HMAC algorithms are supported: hmac(sha1) and
hmac(sha256).
In order to avoid dynamic memory allocation for each HMAC computation,
a per-cpu ring buffer is allocated for this purpose.
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
---
include/linux/seg6_hmac.h | 6 +
include/net/seg6_hmac.h | 61 ++++++
include/uapi/linux/seg6_hmac.h | 20 ++
net/ipv6/Kconfig | 12 ++
net/ipv6/seg6_hmac.c | 432 +++++++++++++++++++++++++++++++++++++++++
5 files changed, 531 insertions(+)
create mode 100644 include/linux/seg6_hmac.h
create mode 100644 include/net/seg6_hmac.h
create mode 100644 include/uapi/linux/seg6_hmac.h
create mode 100644 net/ipv6/seg6_hmac.c
diff --git a/include/linux/seg6_hmac.h b/include/linux/seg6_hmac.h
new file mode 100644
index 0000000..da437eb
--- /dev/null
+++ b/include/linux/seg6_hmac.h
@@ -0,0 +1,6 @@
+#ifndef _LINUX_SEG6_HMAC_H
+#define _LINUX_SEG6_HMAC_H
+
+#include <uapi/linux/seg6_hmac.h>
+
+#endif
diff --git a/include/net/seg6_hmac.h b/include/net/seg6_hmac.h
new file mode 100644
index 0000000..6e5ee6a
--- /dev/null
+++ b/include/net/seg6_hmac.h
@@ -0,0 +1,61 @@
+/*
+ * SR-IPv6 implementation
+ *
+ * Author:
+ * David Lebrun <david.lebrun@uclouvain.be>
+ *
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _NET_SEG6_HMAC_H
+#define _NET_SEG6_HMAC_H
+
+#include <net/flow.h>
+#include <net/ip6_fib.h>
+#include <net/sock.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <linux/route.h>
+#include <net/seg6.h>
+#include <linux/seg6_hmac.h>
+
+#define SEG6_HMAC_MAX_DIGESTSIZE 160
+#define SEG6_HMAC_RING_SIZE 256
+
+struct seg6_hmac_info {
+ struct list_head list;
+
+ u32 hmackeyid;
+ char secret[SEG6_HMAC_SECRET_LEN];
+ u8 slen;
+ u8 alg_id;
+};
+
+struct seg6_hmac_algo {
+ u8 alg_id;
+ char name[64];
+ struct crypto_shash * __percpu *tfms;
+ struct shash_desc * __percpu *shashs;
+};
+
+extern int seg6_hmac_compute(struct seg6_hmac_info *hinfo,
+ struct ipv6_sr_hdr *hdr, struct in6_addr *saddr,
+ u8 *output);
+extern struct seg6_hmac_info *seg6_hmac_info_lookup(struct net *net, u32 key);
+extern int seg6_hmac_info_add(struct net *net, u32 key,
+ struct seg6_hmac_info *hinfo);
+extern int seg6_hmac_info_del(struct net *net, u32 key,
+ struct seg6_hmac_info *hinfo);
+extern int seg6_push_hmac(struct net *net, struct in6_addr *saddr,
+ struct ipv6_sr_hdr *srh);
+extern bool seg6_hmac_validate_skb(struct sk_buff *skb);
+extern int seg6_hmac_init(void);
+extern void seg6_hmac_exit(void);
+extern int seg6_hmac_net_init(struct net *net);
+extern void seg6_hmac_net_exit(struct net *net);
+
+#endif
diff --git a/include/uapi/linux/seg6_hmac.h b/include/uapi/linux/seg6_hmac.h
new file mode 100644
index 0000000..0b5eda7
--- /dev/null
+++ b/include/uapi/linux/seg6_hmac.h
@@ -0,0 +1,20 @@
+#ifndef _UAPI_LINUX_SEG6_HMAC_H
+#define _UAPI_LINUX_SEG6_HMAC_H
+
+#define SEG6_HMAC_SECRET_LEN 64
+#define SEG6_HMAC_FIELD_LEN 32
+
+struct sr6_tlv_hmac {
+ __u8 type;
+ __u8 len;
+ __u16 reserved;
+ __be32 hmackeyid;
+ __u8 hmac[SEG6_HMAC_FIELD_LEN];
+} __attribute__((packed));
+
+enum {
+ SEG6_HMAC_ALGO_SHA1 = 1,
+ SEG6_HMAC_ALGO_SHA256 = 2,
+};
+
+#endif
diff --git a/net/ipv6/Kconfig b/net/ipv6/Kconfig
index 2343e4f..c647712 100644
--- a/net/ipv6/Kconfig
+++ b/net/ipv6/Kconfig
@@ -289,4 +289,16 @@ config IPV6_PIMSM_V2
Support for IPv6 PIM multicast routing protocol PIM-SMv2.
If unsure, say N.
+config IPV6_SEG6_HMAC
+ bool "IPv6: Segment Routing HMAC support"
+ depends on IPV6
+ select CRYPTO_HMAC
+ select CRYPTO_SHA1
+ select CRYPTO_SHA256
+ ---help---
+ Support for HMAC signature generation and verification
+ of SR-enabled packets.
+
+ If unsure, say N.
+
endif # IPV6
diff --git a/net/ipv6/seg6_hmac.c b/net/ipv6/seg6_hmac.c
new file mode 100644
index 0000000..65ebc0c
--- /dev/null
+++ b/net/ipv6/seg6_hmac.c
@@ -0,0 +1,432 @@
+/*
+ * SR-IPv6 implementation -- HMAC functions
+ *
+ * Author:
+ * David Lebrun <david.lebrun@uclouvain.be>
+ *
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <linux/net.h>
+#include <linux/netdevice.h>
+#include <linux/in6.h>
+#include <linux/icmpv6.h>
+#include <linux/mroute6.h>
+#include <linux/slab.h>
+
+#include <linux/netfilter.h>
+#include <linux/netfilter_ipv6.h>
+
+#include <net/sock.h>
+#include <net/snmp.h>
+
+#include <net/ipv6.h>
+#include <net/protocol.h>
+#include <net/transp_v6.h>
+#include <net/rawv6.h>
+#include <net/ndisc.h>
+#include <net/ip6_route.h>
+#include <net/addrconf.h>
+#include <net/xfrm.h>
+
+#include <linux/cryptohash.h>
+#include <crypto/hash.h>
+#include <crypto/sha.h>
+#include <net/seg6.h>
+#include <net/genetlink.h>
+#include <net/seg6_hmac.h>
+#include <linux/random.h>
+
+static char * __percpu *hmac_ring;
+
+static struct seg6_hmac_algo hmac_algos[] = {
+ {
+ .alg_id = SEG6_HMAC_ALGO_SHA1,
+ .name = "hmac(sha1)",
+ },
+ {
+ .alg_id = SEG6_HMAC_ALGO_SHA256,
+ .name = "hmac(sha256)",
+ },
+};
+
+static struct seg6_hmac_algo *__hmac_get_algo(u8 alg_id)
+{
+ struct seg6_hmac_algo *algo;
+ int i, alg_count;
+
+ alg_count = sizeof(hmac_algos) / sizeof(struct seg6_hmac_algo);
+ for (i = 0; i < alg_count; i++) {
+ algo = &hmac_algos[i];
+ if (algo->alg_id == alg_id)
+ return algo;
+ }
+
+ return NULL;
+}
+
+static int __do_hmac(struct seg6_hmac_info *hinfo, const char *text, u8 psize,
+ u8 *output, int outlen)
+{
+ struct seg6_hmac_algo *algo;
+ struct crypto_shash *tfm;
+ struct shash_desc *shash;
+ int ret, dgsize;
+
+ algo = __hmac_get_algo(hinfo->alg_id);
+ if (!algo)
+ return -ENOENT;
+
+ tfm = *this_cpu_ptr(algo->tfms);
+
+ dgsize = crypto_shash_digestsize(tfm);
+ if (dgsize > outlen) {
+ pr_debug("sr-ipv6: __do_hmac: digest size too big (%d / %d)\n",
+ dgsize, outlen);
+ return -ENOMEM;
+ }
+
+ ret = crypto_shash_setkey(tfm, hinfo->secret, hinfo->slen);
+ if (ret < 0) {
+ pr_debug("sr-ipv6: crypto_shash_setkey failed: err %d\n", ret);
+ goto failed;
+ }
+
+ shash = *this_cpu_ptr(algo->shashs);
+ shash->tfm = tfm;
+
+ ret = crypto_shash_digest(shash, text, psize, output);
+ if (ret < 0) {
+ pr_debug("sr-ipv6: crypto_shash_digest failed: err %d\n", ret);
+ goto failed;
+ }
+
+ return dgsize;
+
+failed:
+ return ret;
+}
+
+int seg6_hmac_compute(struct seg6_hmac_info *hinfo, struct ipv6_sr_hdr *hdr,
+ struct in6_addr *saddr, u8 *output)
+{
+ __be32 hmackeyid = cpu_to_be32(hinfo->hmackeyid);
+ u8 tmp_out[SEG6_HMAC_MAX_DIGESTSIZE];
+ int plen, i, dgsize, wrsize;
+ char *ring, *off;
+
+ /* a 160-byte buffer for digest output allows to store highest known
+ * hash function (RadioGatun) with up to 1216 bits
+ */
+
+ /* saddr(16) + first_seg(1) + cleanup(1) + keyid(4) + seglist(16n) */
+ plen = 16 + 1 + 1 + 4 + (hdr->first_segment + 1) * 16;
+
+ /* this limit allows for 14 segments */
+ if (plen >= SEG6_HMAC_RING_SIZE)
+ return -EMSGSIZE;
+
+ local_bh_disable();
+ ring = *this_cpu_ptr(hmac_ring);
+ off = ring;
+ memcpy(off, saddr, 16);
+ off += 16;
+ *off++ = hdr->first_segment;
+ *off++ = !!(sr_has_cleanup(hdr)) << 7;
+ memcpy(off, &hmackeyid, 4);
+ off += 4;
+
+ for (i = 0; i < hdr->first_segment + 1; i++) {
+ memcpy(off, hdr->segments + i, 16);
+ off += 16;
+ }
+
+ dgsize = __do_hmac(hinfo, ring, plen, tmp_out,
+ SEG6_HMAC_MAX_DIGESTSIZE);
+ local_bh_enable();
+
+ if (dgsize < 0)
+ return dgsize;
+
+ wrsize = SEG6_HMAC_FIELD_LEN;
+ if (wrsize > dgsize)
+ wrsize = dgsize;
+
+ memset(output, 0, SEG6_HMAC_FIELD_LEN);
+ memcpy(output, tmp_out, wrsize);
+
+ return 0;
+}
+EXPORT_SYMBOL(seg6_hmac_compute);
+
+/* checks if an incoming SR-enabled packet's HMAC status matches
+ * the incoming policy.
+ *
+ * called with rcu_read_lock()
+ */
+bool seg6_hmac_validate_skb(struct sk_buff *skb)
+{
+ u8 hmac_output[SEG6_HMAC_FIELD_LEN];
+ struct net *net = dev_net(skb->dev);
+ struct seg6_hmac_info *hinfo;
+ struct sr6_tlv_hmac *tlv;
+ struct ipv6_sr_hdr *srh;
+ struct inet6_dev *idev;
+
+ idev = __in6_dev_get(skb->dev);
+
+ srh = (struct ipv6_sr_hdr *)skb_transport_header(skb);
+
+ tlv = seg6_get_tlv_hmac(srh);
+
+ /* mandatory check but no tlv */
+ if (idev->cnf.seg6_require_hmac > 0 && !tlv)
+ return false;
+
+ /* no check */
+ if (idev->cnf.seg6_require_hmac < 0)
+ return true;
+
+ /* check only if present */
+ if (idev->cnf.seg6_require_hmac == 0 && !tlv)
+ return true;
+
+ /* now, seg6_require_hmac >= 0 && tlv */
+
+ hinfo = seg6_hmac_info_lookup(net, be32_to_cpu(tlv->hmackeyid));
+ if (!hinfo)
+ return false;
+
+ if (seg6_hmac_compute(hinfo, srh, &ipv6_hdr(skb)->saddr, hmac_output))
+ return false;
+
+ if (memcmp(hmac_output, tlv->hmac, SEG6_HMAC_FIELD_LEN) != 0)
+ return false;
+
+ return true;
+}
+
+/* called with rcu_read_lock() */
+struct seg6_hmac_info *seg6_hmac_info_lookup(struct net *net, u32 key)
+{
+ struct seg6_pernet_data *sdata = seg6_pernet(net);
+ struct seg6_hmac_info *hinfo;
+
+ list_for_each_entry_rcu(hinfo, &sdata->hmac_infos, list) {
+ if (hinfo->hmackeyid == key)
+ return hinfo;
+ }
+
+ return NULL;
+}
+EXPORT_SYMBOL(seg6_hmac_info_lookup);
+
+int seg6_hmac_info_add(struct net *net, u32 key, struct seg6_hmac_info *hinfo)
+{
+ struct seg6_pernet_data *sdata = seg6_pernet(net);
+ struct seg6_hmac_info *old_hinfo;
+
+ old_hinfo = seg6_hmac_info_lookup(net, key);
+ if (old_hinfo)
+ return -EEXIST;
+
+ list_add_rcu(&hinfo->list, &sdata->hmac_infos);
+
+ return 0;
+}
+EXPORT_SYMBOL(seg6_hmac_info_add);
+
+int seg6_hmac_info_del(struct net *net, u32 key, struct seg6_hmac_info *hinfo)
+{
+ struct seg6_hmac_info *tmp;
+
+ tmp = seg6_hmac_info_lookup(net, key);
+ if (!tmp)
+ return -ENOENT;
+
+ /* entry was replaced, ignore deletion */
+ if (tmp != hinfo)
+ return -ENOENT;
+
+ list_del_rcu(&hinfo->list);
+ synchronize_net();
+
+ return 0;
+}
+EXPORT_SYMBOL(seg6_hmac_info_del);
+
+static void seg6_hmac_info_flush(struct net *net)
+{
+ struct seg6_pernet_data *sdata = seg6_pernet(net);
+ struct seg6_hmac_info *hinfo;
+
+ mutex_lock(&sdata->lock);
+ while ((hinfo = list_first_or_null_rcu(&sdata->hmac_infos,
+ struct seg6_hmac_info,
+ list)) != NULL) {
+ list_del_rcu(&hinfo->list);
+ mutex_unlock(&sdata->lock);
+ synchronize_net();
+ kfree(hinfo);
+ mutex_lock(&sdata->lock);
+ }
+
+ mutex_unlock(&sdata->lock);
+}
+
+int seg6_push_hmac(struct net *net, struct in6_addr *saddr,
+ struct ipv6_sr_hdr *srh)
+{
+ struct seg6_hmac_info *hinfo;
+ struct sr6_tlv_hmac *tlv;
+ int err = -ENOENT;
+
+ tlv = seg6_get_tlv_hmac(srh);
+ if (!tlv)
+ return -EINVAL;
+
+ rcu_read_lock();
+
+ hinfo = seg6_hmac_info_lookup(net, be32_to_cpu(tlv->hmackeyid));
+ if (!hinfo)
+ goto out;
+
+ memset(tlv->hmac, 0, SEG6_HMAC_FIELD_LEN);
+ err = seg6_hmac_compute(hinfo, srh, saddr, tlv->hmac);
+
+out:
+ rcu_read_unlock();
+ return err;
+}
+EXPORT_SYMBOL(seg6_push_hmac);
+
+static int seg6_hmac_init_ring(void)
+{
+ int i;
+
+ hmac_ring = alloc_percpu(char *);
+
+ if (!hmac_ring)
+ return -ENOMEM;
+
+ for_each_possible_cpu(i) {
+ char *ring = kzalloc(SEG6_HMAC_RING_SIZE, GFP_KERNEL);
+
+ if (!ring)
+ return -ENOMEM;
+
+ *per_cpu_ptr(hmac_ring, i) = ring;
+ }
+
+ return 0;
+}
+
+static int seg6_hmac_init_algo(void)
+{
+ struct seg6_hmac_algo *algo;
+ struct crypto_shash *tfm;
+ struct shash_desc *shash;
+ int i, alg_count, cpu;
+
+ alg_count = sizeof(hmac_algos) / sizeof(struct seg6_hmac_algo);
+
+ for (i = 0; i < alg_count; i++) {
+ struct crypto_shash **p_tfm;
+ int shsize;
+
+ algo = &hmac_algos[i];
+ algo->tfms = alloc_percpu(struct crypto_shash *);
+ if (!algo->tfms)
+ return -ENOMEM;
+
+ for_each_possible_cpu(cpu) {
+ tfm = crypto_alloc_shash(algo->name, 0, GFP_KERNEL);
+ if (IS_ERR(tfm))
+ return PTR_ERR(tfm);
+ p_tfm = per_cpu_ptr(algo->tfms, cpu);
+ *p_tfm = tfm;
+ }
+
+ p_tfm = this_cpu_ptr(algo->tfms);
+ tfm = *p_tfm;
+
+ shsize = sizeof(*shash) + crypto_shash_descsize(tfm);
+
+ algo->shashs = alloc_percpu(struct shash_desc *);
+ if (!algo->shashs)
+ return -ENOMEM;
+
+ for_each_possible_cpu(cpu) {
+ shash = kzalloc(shsize, GFP_KERNEL);
+ if (!shash)
+ return -ENOMEM;
+ *per_cpu_ptr(algo->shashs, cpu) = shash;
+ }
+ }
+
+ return 0;
+}
+
+int __init seg6_hmac_init(void)
+{
+ int ret;
+
+ ret = seg6_hmac_init_ring();
+ if (ret < 0)
+ goto out;
+
+ ret = seg6_hmac_init_algo();
+
+out:
+ return ret;
+}
+
+int __net_init seg6_hmac_net_init(struct net *net)
+{
+ struct seg6_pernet_data *sdata = seg6_pernet(net);
+
+ INIT_LIST_HEAD(&sdata->hmac_infos);
+ return 0;
+}
+
+void __exit seg6_hmac_exit(void)
+{
+ struct seg6_hmac_algo *algo = NULL;
+ int i, alg_count, cpu;
+
+ for_each_possible_cpu(i) {
+ char *ring = *per_cpu_ptr(hmac_ring, i);
+
+ kfree(ring);
+ }
+ free_percpu(hmac_ring);
+
+ alg_count = sizeof(hmac_algos) / sizeof(struct seg6_hmac_algo);
+ for (i = 0; i < alg_count; i++) {
+ algo = &hmac_algos[i];
+ for_each_possible_cpu(cpu) {
+ struct crypto_shash *tfm;
+ struct shash_desc *shash;
+
+ shash = *per_cpu_ptr(algo->shashs, cpu);
+ kfree(shash);
+ tfm = *per_cpu_ptr(algo->tfms, cpu);
+ crypto_free_shash(tfm);
+ }
+ free_percpu(algo->tfms);
+ free_percpu(algo->shashs);
+ }
+}
+
+void __net_exit seg6_hmac_net_exit(struct net *net)
+{
+ seg6_hmac_info_flush(net);
+}
--
2.7.3
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v2 5/9] ipv6: sr: implement API to control SR HMAC structure
2016-10-26 15:54 [PATCH v2 0/9] net: add support for IPv6 Segment Routing David Lebrun
` (3 preceding siblings ...)
2016-10-26 15:54 ` [PATCH v2 4/9] ipv6: sr: add core files for SR HMAC support David Lebrun
@ 2016-10-26 15:56 ` David Lebrun
2016-10-26 15:56 ` [PATCH v2 6/9] ipv6: sr: add calls to verify and insert HMAC signatures David Lebrun
` (4 subsequent siblings)
9 siblings, 0 replies; 15+ messages in thread
From: David Lebrun @ 2016-10-26 15:56 UTC (permalink / raw)
To: netdev; +Cc: David Lebrun
This patch provides an implementation of the genetlink commands
to associate a given HMAC key identifier with an hashing algorithm
and a secret. It also provides a per-interface sysctl called
seg6_require_hmac, allowing a user-defined policy for processing
HMAC-signed SR-enabled packets. A value of -1 means that the HMAC
field will always be ignored. A value of 0 means that if an HMAC
field is present, its validity will be enforced (the packet is
dropped is the signature is incorrect). Finally, a value of 1 means
that any SR-enabled packet that does not contain an HMAC signature
or whose signature is incorrect will be dropped.
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
---
include/linux/ipv6.h | 3 +
include/net/seg6.h | 10 +++
include/net/seg6_hmac.h | 1 +
include/uapi/linux/ipv6.h | 1 +
net/ipv6/Makefile | 1 +
net/ipv6/addrconf.c | 18 +++++
net/ipv6/seg6.c | 189 ++++++++++++++++++++++++++++++++++++++++++++++
7 files changed, 223 insertions(+)
diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h
index 76830e6..bad8363 100644
--- a/include/linux/ipv6.h
+++ b/include/linux/ipv6.h
@@ -65,6 +65,9 @@ struct ipv6_devconf {
__s32 use_oif_addrs_only;
__s32 keep_addr_on_down;
__s32 seg6_enabled;
+#ifdef CONFIG_IPV6_SEG6_HMAC
+ __s32 seg6_require_hmac;
+#endif
struct ctl_table_header *sysctl_header;
};
diff --git a/include/net/seg6.h b/include/net/seg6.h
index 53d3bdb..a4062db 100644
--- a/include/net/seg6.h
+++ b/include/net/seg6.h
@@ -17,10 +17,16 @@
#include <linux/net.h>
#include <linux/ipv6.h>
#include <net/lwtunnel.h>
+#ifdef CONFIG_IPV6_SEG6_HMAC
+#include <net/seg6_hmac.h>
+#endif
struct seg6_pernet_data {
struct mutex lock;
struct in6_addr __rcu *tun_src;
+#ifdef CONFIG_IPV6_SEG6_HMAC
+ struct list_head hmac_infos;
+#endif
};
static inline struct seg6_pernet_data *seg6_pernet(struct net *net)
@@ -28,4 +34,8 @@ static inline struct seg6_pernet_data *seg6_pernet(struct net *net)
return net->ipv6.seg6_data;
}
+#ifdef CONFIG_IPV6_SEG6_HMAC
+extern struct sr6_tlv_hmac *seg6_get_tlv_hmac(struct ipv6_sr_hdr *srh);
+#endif
+
#endif
diff --git a/include/net/seg6_hmac.h b/include/net/seg6_hmac.h
index 6e5ee6a..9646b7e 100644
--- a/include/net/seg6_hmac.h
+++ b/include/net/seg6_hmac.h
@@ -21,6 +21,7 @@
#include <linux/ipv6.h>
#include <linux/route.h>
#include <net/seg6.h>
+#include <linux/seg6.h>
#include <linux/seg6_hmac.h>
#define SEG6_HMAC_MAX_DIGESTSIZE 160
diff --git a/include/uapi/linux/ipv6.h b/include/uapi/linux/ipv6.h
index 7ff1d65..53561be 100644
--- a/include/uapi/linux/ipv6.h
+++ b/include/uapi/linux/ipv6.h
@@ -180,6 +180,7 @@ enum {
DEVCONF_KEEP_ADDR_ON_DOWN,
DEVCONF_RTR_SOLICIT_MAX_INTERVAL,
DEVCONF_SEG6_ENABLED,
+ DEVCONF_SEG6_REQUIRE_HMAC,
DEVCONF_MAX
};
diff --git a/net/ipv6/Makefile b/net/ipv6/Makefile
index 4bd1e73..81a70b1 100644
--- a/net/ipv6/Makefile
+++ b/net/ipv6/Makefile
@@ -44,6 +44,7 @@ obj-$(CONFIG_IPV6_SIT) += sit.o
obj-$(CONFIG_IPV6_TUNNEL) += ip6_tunnel.o
obj-$(CONFIG_IPV6_GRE) += ip6_gre.o
obj-$(CONFIG_IPV6_FOU) += fou6.o
+obj-$(CONFIG_IPV6_SEG6_HMAC) += seg6_hmac.o
obj-y += addrconf_core.o exthdrs_core.o ip6_checksum.o ip6_icmp.o seg6.o seg6_iptunnel.o
obj-$(CONFIG_INET) += output_core.o protocol.o $(ipv6-offload)
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 8d068ee..6e5f72b 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -240,6 +240,9 @@ static struct ipv6_devconf ipv6_devconf __read_mostly = {
.ignore_routes_with_linkdown = 0,
.keep_addr_on_down = 0,
.seg6_enabled = 0,
+#ifdef CONFIG_IPV6_SEG6_HMAC
+ .seg6_require_hmac = 0,
+#endif
};
static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
@@ -287,6 +290,9 @@ static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
.ignore_routes_with_linkdown = 0,
.keep_addr_on_down = 0,
.seg6_enabled = 0,
+#ifdef CONFIG_IPV6_SEG6_HMAC
+ .seg6_require_hmac = 0,
+#endif
};
/* Check if a valid qdisc is available */
@@ -4968,6 +4974,9 @@ static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
+#ifdef CONFIG_IPV6_SEG6_HMAC
+ array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
+#endif
}
static inline size_t inet6_ifla6_size(void)
@@ -6066,6 +6075,15 @@ static const struct ctl_table addrconf_sysctl[] = {
.mode = 0644,
.proc_handler = proc_dointvec,
},
+#ifdef CONFIG_IPV6_SEG6_HMAC
+ {
+ .procname = "seg6_require_hmac",
+ .data = &ipv6_devconf.seg6_require_hmac,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
+#endif
{
/* sentinel */
}
diff --git a/net/ipv6/seg6.c b/net/ipv6/seg6.c
index 24111662..e967f4f 100644
--- a/net/ipv6/seg6.c
+++ b/net/ipv6/seg6.c
@@ -25,6 +25,9 @@
#include <net/genetlink.h>
#include <linux/seg6.h>
#include <linux/seg6_genl.h>
+#ifdef CONFIG_IPV6_SEG6_HMAC
+#include <net/seg6_hmac.h>
+#endif
static const struct nla_policy seg6_genl_policy[SEG6_ATTR_MAX + 1] = {
[SEG6_ATTR_DST] = { .type = NLA_BINARY,
@@ -46,11 +49,108 @@ static struct genl_family seg6_genl_family = {
.netnsok = true,
};
+#ifdef CONFIG_IPV6_SEG6_HMAC
+struct sr6_tlv_hmac *seg6_get_tlv_hmac(struct ipv6_sr_hdr *srh)
+{
+ struct sr6_tlv_hmac *tlv;
+
+ if (srh->hdrlen < (srh->first_segment + 1) * 2 + 5)
+ return NULL;
+
+ if (!sr_has_hmac(srh))
+ return NULL;
+
+ tlv = (struct sr6_tlv_hmac *)
+ ((char *)srh + ((srh->hdrlen + 1) << 3) - 40);
+
+ if (tlv->type != SR6_TLV_HMAC || tlv->len != 38)
+ return NULL;
+
+ return tlv;
+}
+
+static int seg6_genl_sethmac(struct sk_buff *skb, struct genl_info *info)
+{
+ struct net *net = genl_info_net(info);
+ struct seg6_pernet_data *sdata;
+ struct seg6_hmac_info *hinfo;
+ u32 hmackeyid;
+ char *secret;
+ int err = 0;
+ u8 algid;
+ u8 slen;
+
+ sdata = seg6_pernet(net);
+
+ if (!info->attrs[SEG6_ATTR_HMACKEYID] ||
+ !info->attrs[SEG6_ATTR_SECRETLEN] ||
+ !info->attrs[SEG6_ATTR_ALGID])
+ return -EINVAL;
+
+ hmackeyid = nla_get_u32(info->attrs[SEG6_ATTR_HMACKEYID]);
+ slen = nla_get_u8(info->attrs[SEG6_ATTR_SECRETLEN]);
+ algid = nla_get_u8(info->attrs[SEG6_ATTR_ALGID]);
+
+ if (hmackeyid == 0)
+ return -EINVAL;
+
+ if (slen > SEG6_HMAC_SECRET_LEN)
+ return -EINVAL;
+
+ mutex_lock(&sdata->lock);
+ hinfo = seg6_hmac_info_lookup(net, hmackeyid);
+
+ if (!slen) {
+ if (!hinfo || seg6_hmac_info_del(net, hmackeyid, hinfo))
+ err = -ENOENT;
+ else
+ kfree(hinfo);
+
+ goto out_unlock;
+ }
+
+ if (!info->attrs[SEG6_ATTR_SECRET]) {
+ err = -EINVAL;
+ goto out_unlock;
+ }
+
+ if (hinfo) {
+ if (seg6_hmac_info_del(net, hmackeyid, hinfo)) {
+ err = -ENOENT;
+ goto out_unlock;
+ }
+ kfree(hinfo);
+ }
+
+ secret = (char *)nla_data(info->attrs[SEG6_ATTR_SECRET]);
+
+ hinfo = kzalloc(sizeof(*hinfo), GFP_KERNEL);
+ if (!hinfo) {
+ err = -ENOMEM;
+ goto out_unlock;
+ }
+
+ memcpy(hinfo->secret, secret, slen);
+ hinfo->slen = slen;
+ hinfo->alg_id = algid;
+ hinfo->hmackeyid = hmackeyid;
+
+ seg6_hmac_info_add(net, hmackeyid, hinfo);
+
+out_unlock:
+ mutex_unlock(&sdata->lock);
+ return err;
+}
+
+#else
+
static int seg6_genl_sethmac(struct sk_buff *skb, struct genl_info *info)
{
return -ENOTSUPP;
}
+#endif
+
static int seg6_genl_set_tunsrc(struct sk_buff *skb, struct genl_info *info)
{
struct net *net = genl_info_net(info);
@@ -115,11 +215,78 @@ static int seg6_genl_get_tunsrc(struct sk_buff *skb, struct genl_info *info)
return -ENOMEM;
}
+#ifdef CONFIG_IPV6_SEG6_HMAC
+
+static int __seg6_hmac_fill_info(struct seg6_hmac_info *hinfo,
+ struct sk_buff *msg)
+{
+ if (nla_put_u32(msg, SEG6_ATTR_HMACKEYID, hinfo->hmackeyid) ||
+ nla_put_u8(msg, SEG6_ATTR_SECRETLEN, hinfo->slen) ||
+ nla_put(msg, SEG6_ATTR_SECRET, hinfo->slen, hinfo->secret) ||
+ nla_put_u8(msg, SEG6_ATTR_ALGID, hinfo->alg_id))
+ return -1;
+
+ return 0;
+}
+
+static int __seg6_genl_dumphmac_element(struct seg6_hmac_info *hinfo,
+ u32 portid, u32 seq, u32 flags,
+ struct sk_buff *skb, u8 cmd)
+{
+ void *hdr;
+
+ hdr = genlmsg_put(skb, portid, seq, &seg6_genl_family, flags, cmd);
+ if (!hdr)
+ return -ENOMEM;
+
+ if (__seg6_hmac_fill_info(hinfo, skb) < 0)
+ goto nla_put_failure;
+
+ genlmsg_end(skb, hdr);
+ return 0;
+
+nla_put_failure:
+ genlmsg_cancel(skb, hdr);
+ return -EMSGSIZE;
+}
+
+static int seg6_genl_dumphmac(struct sk_buff *skb, struct netlink_callback *cb)
+{
+ struct net *net = sock_net(skb->sk);
+ struct seg6_pernet_data *sdata;
+ struct seg6_hmac_info *hinfo;
+ int idx = 0, ret;
+
+ sdata = seg6_pernet(net);
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(hinfo, &sdata->hmac_infos, list) {
+ if (idx++ < cb->args[0])
+ continue;
+
+ ret = __seg6_genl_dumphmac_element(hinfo,
+ NETLINK_CB(cb->skb).portid,
+ cb->nlh->nlmsg_seq,
+ NLM_F_MULTI,
+ skb, SEG6_CMD_DUMPHMAC);
+ if (ret)
+ break;
+ }
+ rcu_read_unlock();
+
+ cb->args[0] = idx;
+ return skb->len;
+}
+
+#else
+
static int seg6_genl_dumphmac(struct sk_buff *skb, struct netlink_callback *cb)
{
return -ENOTSUPP;
}
+#endif
+
static const struct genl_ops seg6_genl_ops[] = {
{
.cmd = SEG6_CMD_SETHMAC,
@@ -165,6 +332,10 @@ static int __net_init seg6_net_init(struct net *net)
net->ipv6.seg6_data = sdata;
+#ifdef CONFIG_IPV6_SEG6_HMAC
+ seg6_hmac_net_init(net);
+#endif
+
return 0;
}
@@ -172,6 +343,10 @@ static void __net_exit seg6_net_exit(struct net *net)
{
struct seg6_pernet_data *sdata = seg6_pernet(net);
+#ifdef CONFIG_IPV6_SEG6_HMAC
+ seg6_hmac_net_exit(net);
+#endif
+
kfree(sdata->tun_src);
kfree(sdata);
}
@@ -193,10 +368,20 @@ static int __init seg6_init(void)
if (err)
goto out_unregister_genl;
+#ifdef CONFIG_IPV6_SEG6_HMAC
+ err = seg6_hmac_init();
+ if (err)
+ goto out_unregister_pernet;
+#endif
+
pr_info("Segment Routing with IPv6\n");
out:
return err;
+#ifdef CONFIG_IPV6_SEG6_HMAC
+out_unregister_pernet:
+ unregister_pernet_subsys(&ip6_segments_ops);
+#endif
out_unregister_genl:
genl_unregister_family(&seg6_genl_family);
goto out;
@@ -205,6 +390,10 @@ module_init(seg6_init);
static void __exit seg6_exit(void)
{
+#ifdef CONFIG_IPV6_SEG6_HMAC
+ seg6_hmac_exit();
+#endif
+
unregister_pernet_subsys(&ip6_segments_ops);
genl_unregister_family(&seg6_genl_family);
}
--
2.7.3
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v2 6/9] ipv6: sr: add calls to verify and insert HMAC signatures
2016-10-26 15:54 [PATCH v2 0/9] net: add support for IPv6 Segment Routing David Lebrun
` (4 preceding siblings ...)
2016-10-26 15:56 ` [PATCH v2 5/9] ipv6: sr: implement API to control SR HMAC structure David Lebrun
@ 2016-10-26 15:56 ` David Lebrun
2016-10-26 15:56 ` [PATCH v2 7/9] ipv6: add source address argument for ipv6_push_nfrag_opts David Lebrun
` (3 subsequent siblings)
9 siblings, 0 replies; 15+ messages in thread
From: David Lebrun @ 2016-10-26 15:56 UTC (permalink / raw)
To: netdev; +Cc: David Lebrun
This patch enables the verification of the HMAC signature for transiting
SR-enabled packets, and its insertion on encapsulated/injected SRH.
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
---
net/ipv6/exthdrs.c | 10 ++++++++++
net/ipv6/seg6_iptunnel.c | 18 ++++++++++++++++++
2 files changed, 28 insertions(+)
diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c
index cf9f338..9b63932 100644
--- a/net/ipv6/exthdrs.c
+++ b/net/ipv6/exthdrs.c
@@ -48,6 +48,9 @@
#include <net/xfrm.h>
#endif
#include <linux/seg6.h>
+#ifdef CONFIG_IPV6_SEG6_HMAC
+#include <net/seg6_hmac.h>
+#endif
#include <linux/uaccess.h>
@@ -358,6 +361,13 @@ static int ipv6_srh_rcv(struct sk_buff *skb)
return -1;
}
+#ifdef CONFIG_IPV6_SEG6_HMAC
+ if (!seg6_hmac_validate_skb(skb)) {
+ kfree_skb(skb);
+ return -1;
+ }
+#endif
+
looped_back:
if (hdr->segments_left > 0) {
if (hdr->nexthdr != NEXTHDR_IPV6 && hdr->segments_left == 1 &&
diff --git a/net/ipv6/seg6_iptunnel.c b/net/ipv6/seg6_iptunnel.c
index caae8ab..2c53991 100644
--- a/net/ipv6/seg6_iptunnel.c
+++ b/net/ipv6/seg6_iptunnel.c
@@ -126,6 +126,14 @@ static int seg6_do_srh_encap(struct sk_buff *skb, struct ipv6_sr_hdr *osrh)
hdr->daddr = isrh->segments[isrh->first_segment];
set_tun_src(net, skb->dev, &hdr->daddr, &hdr->saddr);
+#ifdef CONFIG_IPV6_SEG6_HMAC
+ if (sr_has_hmac(isrh)) {
+ err = seg6_push_hmac(net, &hdr->saddr, isrh);
+ if (unlikely(err))
+ return err;
+ }
+#endif
+
skb_postpush_rcsum(skb, hdr, tot_len);
return 0;
@@ -167,6 +175,16 @@ static int seg6_do_srh_inline(struct sk_buff *skb, struct ipv6_sr_hdr *osrh)
isrh->segments[0] = hdr->daddr;
hdr->daddr = isrh->segments[isrh->first_segment];
+#ifdef CONFIG_IPV6_SEG6_HMAC
+ if (sr_has_hmac(isrh)) {
+ struct net *net = dev_net(skb_dst(skb)->dev);
+
+ err = seg6_push_hmac(net, &hdr->saddr, isrh);
+ if (unlikely(err))
+ return err;
+ }
+#endif
+
skb_postpush_rcsum(skb, hdr, sizeof(struct ipv6hdr) + hdrlen);
return 0;
--
2.7.3
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v2 7/9] ipv6: add source address argument for ipv6_push_nfrag_opts
2016-10-26 15:54 [PATCH v2 0/9] net: add support for IPv6 Segment Routing David Lebrun
` (5 preceding siblings ...)
2016-10-26 15:56 ` [PATCH v2 6/9] ipv6: sr: add calls to verify and insert HMAC signatures David Lebrun
@ 2016-10-26 15:56 ` David Lebrun
2016-10-26 15:56 ` [PATCH v2 8/9] ipv6: sr: add support for SRH injection through setsockopt David Lebrun
` (2 subsequent siblings)
9 siblings, 0 replies; 15+ messages in thread
From: David Lebrun @ 2016-10-26 15:56 UTC (permalink / raw)
To: netdev; +Cc: David Lebrun
This patch prepares for insertion of SRH through setsockopt().
The new source address argument is used when an HMAC field is
present in the SRH, which must be filled. The HMAC signature
process requires the source address as input text.
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
---
include/net/ipv6.h | 3 ++-
net/ipv6/exthdrs.c | 6 +++---
net/ipv6/ip6_output.c | 5 +++--
net/ipv6/ip6_tunnel.c | 2 +-
4 files changed, 9 insertions(+), 7 deletions(-)
diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index 8fed1cd..0a3622b 100644
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -932,7 +932,8 @@ int ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
*/
void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
- u8 *proto, struct in6_addr **daddr_p);
+ u8 *proto, struct in6_addr **daddr_p,
+ struct in6_addr *saddr);
void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
u8 *proto);
diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c
index 9b63932..28d2629 100644
--- a/net/ipv6/exthdrs.c
+++ b/net/ipv6/exthdrs.c
@@ -874,7 +874,7 @@ int ipv6_parse_hopopts(struct sk_buff *skb)
static void ipv6_push_rthdr(struct sk_buff *skb, u8 *proto,
struct ipv6_rt_hdr *opt,
- struct in6_addr **addr_p)
+ struct in6_addr **addr_p, struct in6_addr *saddr)
{
struct rt0_hdr *phdr, *ihdr;
int hops;
@@ -908,10 +908,10 @@ static void ipv6_push_exthdr(struct sk_buff *skb, u8 *proto, u8 type, struct ipv
void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
u8 *proto,
- struct in6_addr **daddr)
+ struct in6_addr **daddr, struct in6_addr *saddr)
{
if (opt->srcrt) {
- ipv6_push_rthdr(skb, proto, opt->srcrt, daddr);
+ ipv6_push_rthdr(skb, proto, opt->srcrt, daddr, saddr);
/*
* IPV6_RTHDRDSTOPTS is ignored
* unless IPV6_RTHDR is set (RFC3542).
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 6001e78..ddc878d 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -203,7 +203,8 @@ int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
if (opt->opt_flen)
ipv6_push_frag_opts(skb, opt, &proto);
if (opt->opt_nflen)
- ipv6_push_nfrag_opts(skb, opt, &proto, &first_hop);
+ ipv6_push_nfrag_opts(skb, opt, &proto, &first_hop,
+ &fl6->saddr);
}
skb_push(skb, sizeof(struct ipv6hdr));
@@ -1672,7 +1673,7 @@ struct sk_buff *__ip6_make_skb(struct sock *sk,
if (opt && opt->opt_flen)
ipv6_push_frag_opts(skb, opt, &proto);
if (opt && opt->opt_nflen)
- ipv6_push_nfrag_opts(skb, opt, &proto, &final_dst);
+ ipv6_push_nfrag_opts(skb, opt, &proto, &final_dst, &fl6->saddr);
skb_push(skb, sizeof(struct ipv6hdr));
skb_reset_network_header(skb);
diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index 3a70567..9c894c9 100644
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -1155,7 +1155,7 @@ int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield,
if (encap_limit >= 0) {
init_tel_txopt(&opt, encap_limit);
- ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL);
+ ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL, NULL);
}
/* Calculate max headroom for all the headers and adjust
--
2.7.3
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v2 8/9] ipv6: sr: add support for SRH injection through setsockopt
2016-10-26 15:54 [PATCH v2 0/9] net: add support for IPv6 Segment Routing David Lebrun
` (6 preceding siblings ...)
2016-10-26 15:56 ` [PATCH v2 7/9] ipv6: add source address argument for ipv6_push_nfrag_opts David Lebrun
@ 2016-10-26 15:56 ` David Lebrun
2016-10-26 15:56 ` [PATCH v2 9/9] ipv6: sr: add documentation file for per-interface sysctls David Lebrun
2016-10-26 16:03 ` [PATCH v2 0/9] net: add support for IPv6 Segment Routing David Lebrun
9 siblings, 0 replies; 15+ messages in thread
From: David Lebrun @ 2016-10-26 15:56 UTC (permalink / raw)
To: netdev; +Cc: David Lebrun
This patch adds support for per-socket SRH injection with the setsockopt
system call through the IPPROTO_IPV6, IPV6_RTHDR options.
The SRH is pushed through the ipv6_push_nfrag_opts function.
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
---
net/ipv6/exthdrs.c | 79 +++++++++++++++++++++++++++++++++++++++++++++---
net/ipv6/ipv6_sockglue.c | 2 ++
2 files changed, 77 insertions(+), 4 deletions(-)
diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c
index 28d2629..489f9ea 100644
--- a/net/ipv6/exthdrs.c
+++ b/net/ipv6/exthdrs.c
@@ -872,9 +872,9 @@ int ipv6_parse_hopopts(struct sk_buff *skb)
* for headers.
*/
-static void ipv6_push_rthdr(struct sk_buff *skb, u8 *proto,
- struct ipv6_rt_hdr *opt,
- struct in6_addr **addr_p, struct in6_addr *saddr)
+static void ipv6_push_rthdr0(struct sk_buff *skb, u8 *proto,
+ struct ipv6_rt_hdr *opt,
+ struct in6_addr **addr_p, struct in6_addr *saddr)
{
struct rt0_hdr *phdr, *ihdr;
int hops;
@@ -897,6 +897,62 @@ static void ipv6_push_rthdr(struct sk_buff *skb, u8 *proto,
*proto = NEXTHDR_ROUTING;
}
+static void ipv6_push_rthdr4(struct sk_buff *skb, u8 *proto,
+ struct ipv6_rt_hdr *opt,
+ struct in6_addr **addr_p, struct in6_addr *saddr)
+{
+ struct ipv6_sr_hdr *sr_phdr, *sr_ihdr;
+ int plen, hops;
+
+ sr_ihdr = (struct ipv6_sr_hdr *)opt;
+ plen = (sr_ihdr->hdrlen + 1) << 3;
+
+ sr_phdr = (struct ipv6_sr_hdr *)skb_push(skb, plen);
+ memcpy(sr_phdr, sr_ihdr, sizeof(struct ipv6_sr_hdr));
+
+ hops = sr_ihdr->first_segment + 1;
+ memcpy(sr_phdr->segments + 1, sr_ihdr->segments + 1,
+ (hops - 1) * sizeof(struct in6_addr));
+
+ sr_phdr->segments[0] = **addr_p;
+ *addr_p = &sr_ihdr->segments[hops - 1];
+
+#ifdef CONFIG_IPV6_SEG6_HMAC
+ if (sr_has_hmac(sr_phdr)) {
+ struct net *net = NULL;
+
+ if (skb->dev)
+ net = dev_net(skb->dev);
+ else if (skb->sk)
+ net = sock_net(skb->sk);
+
+ WARN_ON(!net);
+
+ if (net)
+ seg6_push_hmac(net, saddr, sr_phdr);
+ }
+#endif
+
+ sr_phdr->nexthdr = *proto;
+ *proto = NEXTHDR_ROUTING;
+}
+
+static void ipv6_push_rthdr(struct sk_buff *skb, u8 *proto,
+ struct ipv6_rt_hdr *opt,
+ struct in6_addr **addr_p, struct in6_addr *saddr)
+{
+ switch (opt->type) {
+ case IPV6_SRCRT_TYPE_0:
+ ipv6_push_rthdr0(skb, proto, opt, addr_p, saddr);
+ break;
+ case IPV6_SRCRT_TYPE_4:
+ ipv6_push_rthdr4(skb, proto, opt, addr_p, saddr);
+ break;
+ default:
+ break;
+ }
+}
+
static void ipv6_push_exthdr(struct sk_buff *skb, u8 *proto, u8 type, struct ipv6_opt_hdr *opt)
{
struct ipv6_opt_hdr *h = (struct ipv6_opt_hdr *)skb_push(skb, ipv6_optlen(opt));
@@ -1138,7 +1194,22 @@ struct in6_addr *fl6_update_dst(struct flowi6 *fl6,
return NULL;
*orig = fl6->daddr;
- fl6->daddr = *((struct rt0_hdr *)opt->srcrt)->addr;
+
+ switch (opt->srcrt->type) {
+ case IPV6_SRCRT_TYPE_0:
+ fl6->daddr = *((struct rt0_hdr *)opt->srcrt)->addr;
+ break;
+ case IPV6_SRCRT_TYPE_4:
+ {
+ struct ipv6_sr_hdr *srh = (struct ipv6_sr_hdr *)opt->srcrt;
+
+ fl6->daddr = srh->segments[srh->first_segment];
+ break;
+ }
+ default:
+ return NULL;
+ }
+
return orig;
}
EXPORT_SYMBOL_GPL(fl6_update_dst);
diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c
index 5330262..3fd6371 100644
--- a/net/ipv6/ipv6_sockglue.c
+++ b/net/ipv6/ipv6_sockglue.c
@@ -429,6 +429,8 @@ static int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
break;
#endif
+ case IPV6_SRCRT_TYPE_4:
+ break;
default:
goto sticky_done;
}
--
2.7.3
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v2 9/9] ipv6: sr: add documentation file for per-interface sysctls
2016-10-26 15:54 [PATCH v2 0/9] net: add support for IPv6 Segment Routing David Lebrun
` (7 preceding siblings ...)
2016-10-26 15:56 ` [PATCH v2 8/9] ipv6: sr: add support for SRH injection through setsockopt David Lebrun
@ 2016-10-26 15:56 ` David Lebrun
2016-10-26 16:03 ` [PATCH v2 0/9] net: add support for IPv6 Segment Routing David Lebrun
9 siblings, 0 replies; 15+ messages in thread
From: David Lebrun @ 2016-10-26 15:56 UTC (permalink / raw)
To: netdev; +Cc: David Lebrun
This patch adds documentation for some SR-related per-interface
sysctls.
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
---
Documentation/networking/seg6-sysctl.txt | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
create mode 100644 Documentation/networking/seg6-sysctl.txt
diff --git a/Documentation/networking/seg6-sysctl.txt b/Documentation/networking/seg6-sysctl.txt
new file mode 100644
index 0000000..bdbde23
--- /dev/null
+++ b/Documentation/networking/seg6-sysctl.txt
@@ -0,0 +1,18 @@
+/proc/sys/net/conf/<iface>/seg6_* variables:
+
+seg6_enabled - BOOL
+ Accept or drop SR-enabled IPv6 packets on this interface.
+
+ Relevant packets are those with SRH present and DA = local.
+
+ 0 - disabled (default)
+ not 0 - enabled
+
+seg6_require_hmac - INTEGER
+ Define HMAC policy for ingress SR-enabled packets on this interface.
+
+ -1 - Ignore HMAC field
+ 0 - Accept SR packets without HMAC, validate SR packets with HMAC
+ 1 - Drop SR packets without HMAC, validate SR packets with HMAC
+
+ Default is 0.
--
2.7.3
^ permalink raw reply related [flat|nested] 15+ messages in thread
* Re: [PATCH v2 0/9] net: add support for IPv6 Segment Routing
2016-10-26 15:54 [PATCH v2 0/9] net: add support for IPv6 Segment Routing David Lebrun
` (8 preceding siblings ...)
2016-10-26 15:56 ` [PATCH v2 9/9] ipv6: sr: add documentation file for per-interface sysctls David Lebrun
@ 2016-10-26 16:03 ` David Lebrun
9 siblings, 0 replies; 15+ messages in thread
From: David Lebrun @ 2016-10-26 16:03 UTC (permalink / raw)
To: Linux Kernel Network Developers; +Cc: David Lebrun
[-- Attachment #1: Type: text/plain, Size: 734 bytes --]
On 10/26/2016 05:54 PM, David Lebrun wrote:
> struct ipv6_sr_hdr {
> __u8 nexthdr;
> __u8 hdrlen;
> __u8 type;
> __u8 segments_left;
> __u8 first_segment;
> __be16 flags;
> __u8 reserved;
>
> struct in6_addr segments[0];
> } __attribute__((packed));
I forgot to update the struct in the cover letter description, please
disregard. Actual struct is:
struct ipv6_sr_hdr {
__u8 nexthdr;
__u8 hdrlen;
__u8 type;
__u8 segments_left;
__u8 first_segment;
__u8 flag_1;
__u8 flag_2;
__u8 reserved;
struct in6_addr segments[0];
};
[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 163 bytes --]
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v2 1/9] ipv6: implement dataplane support for rthdr type 4 (Segment Routing Header)
2016-10-26 15:54 ` [PATCH v2 1/9] ipv6: implement dataplane support for rthdr type 4 (Segment Routing Header) David Lebrun
@ 2016-10-28 2:50 ` Tom Herbert
0 siblings, 0 replies; 15+ messages in thread
From: Tom Herbert @ 2016-10-28 2:50 UTC (permalink / raw)
To: David Lebrun; +Cc: Linux Kernel Network Developers
On Wed, Oct 26, 2016 at 8:54 AM, David Lebrun <david.lebrun@uclouvain.be> wrote:
> Implement minimal support for processing of SR-enabled packets
> as described in
> https://tools.ietf.org/html/draft-ietf-6man-segment-routing-header-02.
>
> This patch implements the following operations:
> - Intermediate segment endpoint: incrementation of active segment and rerouting.
> - Egress for SR-encapsulated packets: decapsulation of outer IPv6 header + SRH
> and routing of inner packet.
> - Cleanup flag support for SR-inlined packets: removal of SRH if we are the
> penultimate segment endpoint.
>
> A per-interface sysctl seg6_enabled is provided, to accept/deny SR-enabled
> packets. Default is deny.
>
> This patch does not provide support for HMAC-signed packets.
>
> Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
> ---
> include/linux/ipv6.h | 1 +
> include/linux/seg6.h | 6 ++
> include/uapi/linux/ipv6.h | 2 +
> include/uapi/linux/seg6.h | 48 ++++++++++++
> net/ipv6/addrconf.c | 10 +++
> net/ipv6/exthdrs.c | 183 ++++++++++++++++++++++++++++++++++++++++++++++
> 6 files changed, 250 insertions(+)
> create mode 100644 include/linux/seg6.h
> create mode 100644 include/uapi/linux/seg6.h
>
> diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h
> index 7e9a789..76830e6 100644
> --- a/include/linux/ipv6.h
> +++ b/include/linux/ipv6.h
> @@ -64,6 +64,7 @@ struct ipv6_devconf {
> } stable_secret;
> __s32 use_oif_addrs_only;
> __s32 keep_addr_on_down;
> + __s32 seg6_enabled;
>
> struct ctl_table_header *sysctl_header;
> };
> diff --git a/include/linux/seg6.h b/include/linux/seg6.h
> new file mode 100644
> index 0000000..7a66d2b
> --- /dev/null
> +++ b/include/linux/seg6.h
> @@ -0,0 +1,6 @@
> +#ifndef _LINUX_SEG6_H
> +#define _LINUX_SEG6_H
> +
> +#include <uapi/linux/seg6.h>
> +
> +#endif
> diff --git a/include/uapi/linux/ipv6.h b/include/uapi/linux/ipv6.h
> index 8c27723..7ff1d65 100644
> --- a/include/uapi/linux/ipv6.h
> +++ b/include/uapi/linux/ipv6.h
> @@ -39,6 +39,7 @@ struct in6_ifreq {
> #define IPV6_SRCRT_STRICT 0x01 /* Deprecated; will be removed */
> #define IPV6_SRCRT_TYPE_0 0 /* Deprecated; will be removed */
> #define IPV6_SRCRT_TYPE_2 2 /* IPv6 type 2 Routing Header */
> +#define IPV6_SRCRT_TYPE_4 4 /* Segment Routing with IPv6 */
>
> /*
> * routing header
> @@ -178,6 +179,7 @@ enum {
> DEVCONF_DROP_UNSOLICITED_NA,
> DEVCONF_KEEP_ADDR_ON_DOWN,
> DEVCONF_RTR_SOLICIT_MAX_INTERVAL,
> + DEVCONF_SEG6_ENABLED,
> DEVCONF_MAX
> };
>
> diff --git a/include/uapi/linux/seg6.h b/include/uapi/linux/seg6.h
> new file mode 100644
> index 0000000..7630e7d
> --- /dev/null
> +++ b/include/uapi/linux/seg6.h
> @@ -0,0 +1,48 @@
> +/*
> + * SR-IPv6 implementation
> + *
> + * Author:
> + * David Lebrun <david.lebrun@uclouvain.be>
> + *
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * as published by the Free Software Foundation; either version
> + * 2 of the License, or (at your option) any later version.
> + */
> +
> +#ifndef _UAPI_LINUX_SEG6_H
> +#define _UAPI_LINUX_SEG6_H
> +
> +/*
> + * SRH
> + */
> +struct ipv6_sr_hdr {
> + __u8 nexthdr;
> + __u8 hdrlen;
> + __u8 type;
> + __u8 segments_left;
> + __u8 first_segment;
> + __u8 flag_1;
> + __u8 flag_2;
> + __u8 reserved;
> +
> + struct in6_addr segments[0];
> +};
> +
> +#define SR6_FLAG1_CLEANUP (1 << 7)
> +#define SR6_FLAG1_PROTECTED (1 << 6)
> +#define SR6_FLAG1_OAM (1 << 5)
> +#define SR6_FLAG1_ALERT (1 << 4)
> +#define SR6_FLAG1_HMAC (1 << 3)
> +
> +#define SR6_TLV_INGRESS 1
> +#define SR6_TLV_EGRESS 2
> +#define SR6_TLV_OPAQUE 3
> +#define SR6_TLV_PADDING 4
> +#define SR6_TLV_HMAC 5
> +
> +#define sr_has_cleanup(srh) ((srh)->flag_1 & SR6_FLAG1_CLEANUP)
> +#define sr_has_hmac(srh) ((srh)->flag_1 & SR6_FLAG1_HMAC)
> +
> +#endif
> diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
> index d8983e1..8d068ee 100644
> --- a/net/ipv6/addrconf.c
> +++ b/net/ipv6/addrconf.c
> @@ -239,6 +239,7 @@ static struct ipv6_devconf ipv6_devconf __read_mostly = {
> .use_oif_addrs_only = 0,
> .ignore_routes_with_linkdown = 0,
> .keep_addr_on_down = 0,
> + .seg6_enabled = 0,
> };
>
> static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
> @@ -285,6 +286,7 @@ static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
> .use_oif_addrs_only = 0,
> .ignore_routes_with_linkdown = 0,
> .keep_addr_on_down = 0,
> + .seg6_enabled = 0,
> };
>
> /* Check if a valid qdisc is available */
> @@ -4965,6 +4967,7 @@ static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
> array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
> array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
> array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
> + array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
> }
>
> static inline size_t inet6_ifla6_size(void)
> @@ -6057,6 +6060,13 @@ static const struct ctl_table addrconf_sysctl[] = {
>
> },
> {
> + .procname = "seg6_enabled",
> + .data = &ipv6_devconf.seg6_enabled,
> + .maxlen = sizeof(int),
> + .mode = 0644,
> + .proc_handler = proc_dointvec,
> + },
> + {
> /* sentinel */
> }
> };
> diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c
> index 139ceb6..cf9f338 100644
> --- a/net/ipv6/exthdrs.c
> +++ b/net/ipv6/exthdrs.c
> @@ -47,6 +47,7 @@
> #if IS_ENABLED(CONFIG_IPV6_MIP6)
> #include <net/xfrm.h>
> #endif
> +#include <linux/seg6.h>
>
> #include <linux/uaccess.h>
>
> @@ -286,6 +287,184 @@ static int ipv6_destopt_rcv(struct sk_buff *skb)
> return -1;
> }
>
> +static inline void update_csum_diff4(struct sk_buff *skb, __be32 from,
> + __be32 to)
> +{
> + __be32 diff[] = { ~from, to };
> +
> + skb->csum = ~csum_partial((char *)diff, sizeof(diff), ~skb->csum);
> +}
> +
> +static inline void update_csum_diff16(struct sk_buff *skb, __be32 *from,
> + __be32 *to)
> +{
> + __be32 diff[] = {
> + ~from[0], ~from[1], ~from[2], ~from[3],
> + to[0], to[1], to[2], to[3],
> + };
> +
> + skb->csum = ~csum_partial((char *)diff, sizeof(diff), ~skb->csum);
> +}
These should be in a common header file.
> +
> +static void seg6_update_csum(struct sk_buff *skb)
> +{
> + struct ipv6_sr_hdr *hdr;
> + struct in6_addr *addr;
> + __be32 from, to;
> +
> + /* srh is at transport offset and seg_left is already decremented
> + * but daddr is not yet updated with next segment
> + */
> +
> + hdr = (struct ipv6_sr_hdr *)skb_transport_header(skb);
> + addr = hdr->segments + hdr->segments_left;
> +
> + hdr->segments_left++;
> + from = *(__be32 *)hdr;
> +
> + hdr->segments_left--;
> + to = *(__be32 *)hdr;
> +
> + /* update skb csum with diff resulting from seg_left decrement */
> +
> + update_csum_diff4(skb, from, to);
> +
> + /* compute csum diff between current and next segment and update */
> +
> + update_csum_diff16(skb, (__be32 *)(&ipv6_hdr(skb)->daddr),
> + (__be32 *)addr);
> +}
NIce. Have you tested that checksum offload works if the penultimate
and final addresses are in same host?
> +
> +static int ipv6_srh_rcv(struct sk_buff *skb)
> +{
> + struct inet6_skb_parm *opt = IP6CB(skb);
> + struct net *net = dev_net(skb->dev);
> + struct ipv6_sr_hdr *hdr;
> + struct inet6_dev *idev;
> + struct in6_addr *addr;
> + int cleanup = 0;
Should be a bool?
> + int accept_seg6;
> +
> + hdr = (struct ipv6_sr_hdr *)skb_transport_header(skb);
> +
> + idev = __in6_dev_get(skb->dev);
> +
> + accept_seg6 = net->ipv6.devconf_all->seg6_enabled;
> + if (accept_seg6 > idev->cnf.seg6_enabled)
> + accept_seg6 = idev->cnf.seg6_enabled;
> +
> + if (!accept_seg6) {
> + kfree_skb(skb);
> + return -1;
> + }
> +
> +looped_back:
> + if (hdr->segments_left > 0) {
> + if (hdr->nexthdr != NEXTHDR_IPV6 && hdr->segments_left == 1 &&
> + sr_has_cleanup(hdr))
> + cleanup = 1;
> + } else {
> + if (hdr->nexthdr == NEXTHDR_IPV6) {
> + int offset = (hdr->hdrlen + 1) << 3;
> +
> + skb_postpull_rcsum(skb, skb_network_header(skb),
> + skb_network_header_len(skb));
> +
> + if (!pskb_pull(skb, offset)) {
> + kfree_skb(skb);
> + return -1;
> + }
> + skb_postpull_rcsum(skb, skb_transport_header(skb),
> + offset);
> +
> + skb_reset_network_header(skb);
> + skb_reset_transport_header(skb);
> + skb->encapsulation = 0;
> +
> + __skb_tunnel_rx(skb, skb->dev, net);
> +
> + netif_rx(skb);
> + return -1;
> + }
> +
> + opt->srcrt = skb_network_header_len(skb);
> + opt->lastopt = opt->srcrt;
> + skb->transport_header += (hdr->hdrlen + 1) << 3;
> + opt->nhoff = (&hdr->nexthdr) - skb_network_header(skb);
> +
> + return 1;
> + }
> +
> + if (skb_cloned(skb)) {
> + if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) {
> + __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
> + IPSTATS_MIB_OUTDISCARDS);
> + kfree_skb(skb);
> + return -1;
> + }
> + }
> +
> + hdr = (struct ipv6_sr_hdr *)skb_transport_header(skb);
> +
> + hdr->segments_left--;
> + addr = hdr->segments + hdr->segments_left;
> +
> + skb_push(skb, sizeof(struct ipv6hdr));
> +
> + if (skb->ip_summed == CHECKSUM_COMPLETE)
> + seg6_update_csum(skb);
> +
> + ipv6_hdr(skb)->daddr = *addr;
> +
> + if (cleanup) {
> + int srhlen = (hdr->hdrlen + 1) << 3;
> + int nh = hdr->nexthdr;
> +
> + skb_pull_rcsum(skb, sizeof(struct ipv6hdr) + srhlen);
> + memmove(skb_network_header(skb) + srhlen,
> + skb_network_header(skb),
> + (unsigned char *)hdr - skb_network_header(skb));
> + skb->network_header += srhlen;
> + ipv6_hdr(skb)->nexthdr = nh;
> + ipv6_hdr(skb)->payload_len = htons(skb->len -
> + sizeof(struct ipv6hdr));
> + skb_push_rcsum(skb, sizeof(struct ipv6hdr));
> + }
> +
> + skb_dst_drop(skb);
> +
> + ip6_route_input(skb);
> +
> + if (skb_dst(skb)->error) {
> + dst_input(skb);
> + return -1;
> + }
> +
> + if (skb_dst(skb)->dev->flags & IFF_LOOPBACK) {
> + if (ipv6_hdr(skb)->hop_limit <= 1) {
> + __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
> + IPSTATS_MIB_INHDRERRORS);
> + icmpv6_send(skb, ICMPV6_TIME_EXCEED,
> + ICMPV6_EXC_HOPLIMIT, 0);
> + kfree_skb(skb);
> + return -1;
> + }
> + ipv6_hdr(skb)->hop_limit--;
> +
> + /* be sure that srh is still present before reinjecting */
> + if (!cleanup) {
> + skb_pull(skb, sizeof(struct ipv6hdr));
> + goto looped_back;
> + }
> + skb_set_transport_header(skb, sizeof(struct ipv6hdr));
> + IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr);
> + }
> +
> + dst_input(skb);
> +
> + return -1;
> +}
> +
> /********************************
> Routing header.
> ********************************/
> @@ -326,6 +505,10 @@ static int ipv6_rthdr_rcv(struct sk_buff *skb)
> return -1;
> }
>
> + /* segment routing */
> + if (hdr->type == IPV6_SRCRT_TYPE_4)
> + return ipv6_srh_rcv(skb);
> +
> looped_back:
> if (hdr->segments_left == 0) {
> switch (hdr->type) {
> --
> 2.7.3
>
Acked-by: Tom Herbert <tom@herberland.com>
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v2 2/9] ipv6: sr: add code base for control plane support of SR-IPv6
2016-10-26 15:54 ` [PATCH v2 2/9] ipv6: sr: add code base for control plane support of SR-IPv6 David Lebrun
@ 2016-10-28 2:52 ` Tom Herbert
0 siblings, 0 replies; 15+ messages in thread
From: Tom Herbert @ 2016-10-28 2:52 UTC (permalink / raw)
To: David Lebrun; +Cc: Linux Kernel Network Developers
On Wed, Oct 26, 2016 at 8:54 AM, David Lebrun <david.lebrun@uclouvain.be> wrote:
> This patch adds the necessary hooks and structures to provide support
> for SR-IPv6 control plane, essentially the Generic Netlink commands
> that will be used for userspace control over the Segment Routing
> kernel structures.
>
> The genetlink commands provide control over two different structures:
> tunnel source and HMAC data. The tunnel source is the source address
> that will be used by default when encapsulating packets into an
> outer IPv6 header + SRH. If the tunnel source is set to :: then an
> address of the outgoing interface will be selected as the source.
>
> The HMAC commands currently just return ENOTSUPP and will be implemented
> in a future patch.
>
> Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
> ---
> include/linux/seg6_genl.h | 6 ++
> include/net/netns/ipv6.h | 1 +
> include/net/seg6.h | 30 ++++++
> include/uapi/linux/seg6_genl.h | 32 ++++++
> net/ipv6/Makefile | 2 +-
> net/ipv6/seg6.c | 214 +++++++++++++++++++++++++++++++++++++++++
> 6 files changed, 284 insertions(+), 1 deletion(-)
> create mode 100644 include/linux/seg6_genl.h
> create mode 100644 include/net/seg6.h
> create mode 100644 include/uapi/linux/seg6_genl.h
> create mode 100644 net/ipv6/seg6.c
>
> diff --git a/include/linux/seg6_genl.h b/include/linux/seg6_genl.h
> new file mode 100644
> index 0000000..d6c3fb4f
> --- /dev/null
> +++ b/include/linux/seg6_genl.h
> @@ -0,0 +1,6 @@
> +#ifndef _LINUX_SEG6_GENL_H
> +#define _LINUX_SEG6_GENL_H
> +
> +#include <uapi/linux/seg6_genl.h>
> +
> +#endif
> diff --git a/include/net/netns/ipv6.h b/include/net/netns/ipv6.h
> index 10d0848..de7745e 100644
> --- a/include/net/netns/ipv6.h
> +++ b/include/net/netns/ipv6.h
> @@ -85,6 +85,7 @@ struct netns_ipv6 {
> #endif
> atomic_t dev_addr_genid;
> atomic_t fib6_sernum;
> + struct seg6_pernet_data *seg6_data;
> };
>
> #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
> diff --git a/include/net/seg6.h b/include/net/seg6.h
> new file mode 100644
> index 0000000..a9d9a9b
> --- /dev/null
> +++ b/include/net/seg6.h
> @@ -0,0 +1,30 @@
> +/*
> + * SR-IPv6 implementation
> + *
> + * Author:
> + * David Lebrun <david.lebrun@uclouvain.be>
> + *
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * as published by the Free Software Foundation; either version
> + * 2 of the License, or (at your option) any later version.
> + */
> +
> +#ifndef _NET_SEG6_H
> +#define _NET_SEG6_H
> +
> +#include <linux/net.h>
> +#include <linux/ipv6.h>
> +
> +struct seg6_pernet_data {
> + struct mutex lock;
> + struct in6_addr __rcu *tun_src;
> +};
> +
> +static inline struct seg6_pernet_data *seg6_pernet(struct net *net)
> +{
> + return net->ipv6.seg6_data;
> +}
> +
> +#endif
> diff --git a/include/uapi/linux/seg6_genl.h b/include/uapi/linux/seg6_genl.h
> new file mode 100644
> index 0000000..fcf1c60
> --- /dev/null
> +++ b/include/uapi/linux/seg6_genl.h
> @@ -0,0 +1,32 @@
> +#ifndef _UAPI_LINUX_SEG6_GENL_H
> +#define _UAPI_LINUX_SEG6_GENL_H
> +
> +#define SEG6_GENL_NAME "SEG6"
> +#define SEG6_GENL_VERSION 0x1
> +
> +enum {
> + SEG6_ATTR_UNSPEC,
> + SEG6_ATTR_DST,
> + SEG6_ATTR_DSTLEN,
> + SEG6_ATTR_HMACKEYID,
> + SEG6_ATTR_SECRET,
> + SEG6_ATTR_SECRETLEN,
> + SEG6_ATTR_ALGID,
> + SEG6_ATTR_HMACINFO,
> + __SEG6_ATTR_MAX,
> +};
> +
> +#define SEG6_ATTR_MAX (__SEG6_ATTR_MAX - 1)
> +
> +enum {
> + SEG6_CMD_UNSPEC,
> + SEG6_CMD_SETHMAC,
> + SEG6_CMD_DUMPHMAC,
> + SEG6_CMD_SET_TUNSRC,
> + SEG6_CMD_GET_TUNSRC,
> + __SEG6_CMD_MAX,
> +};
> +
> +#define SEG6_CMD_MAX (__SEG6_CMD_MAX - 1)
> +
> +#endif
> diff --git a/net/ipv6/Makefile b/net/ipv6/Makefile
> index c174ccb..29a77d3 100644
> --- a/net/ipv6/Makefile
> +++ b/net/ipv6/Makefile
> @@ -45,7 +45,7 @@ obj-$(CONFIG_IPV6_TUNNEL) += ip6_tunnel.o
> obj-$(CONFIG_IPV6_GRE) += ip6_gre.o
> obj-$(CONFIG_IPV6_FOU) += fou6.o
>
> -obj-y += addrconf_core.o exthdrs_core.o ip6_checksum.o ip6_icmp.o
> +obj-y += addrconf_core.o exthdrs_core.o ip6_checksum.o ip6_icmp.o seg6.o
> obj-$(CONFIG_INET) += output_core.o protocol.o $(ipv6-offload)
>
> obj-$(subst m,y,$(CONFIG_IPV6)) += inet6_hashtables.o
> diff --git a/net/ipv6/seg6.c b/net/ipv6/seg6.c
> new file mode 100644
> index 0000000..24111662
> --- /dev/null
> +++ b/net/ipv6/seg6.c
> @@ -0,0 +1,214 @@
> +/*
> + * SR-IPv6 implementation
> + *
> + * Author:
> + * David Lebrun <david.lebrun@uclouvain.be>
> + *
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * as published by the Free Software Foundation; either version
> + * 2 of the License, or (at your option) any later version.
> + */
> +
> +#include <linux/errno.h>
> +#include <linux/types.h>
> +#include <linux/socket.h>
> +#include <linux/net.h>
> +#include <linux/in6.h>
> +#include <linux/slab.h>
> +
> +#include <net/ipv6.h>
> +#include <net/protocol.h>
> +
> +#include <net/seg6.h>
> +#include <net/genetlink.h>
> +#include <linux/seg6.h>
> +#include <linux/seg6_genl.h>
> +
> +static const struct nla_policy seg6_genl_policy[SEG6_ATTR_MAX + 1] = {
> + [SEG6_ATTR_DST] = { .type = NLA_BINARY,
> + .len = sizeof(struct in6_addr) },
> + [SEG6_ATTR_DSTLEN] = { .type = NLA_S32, },
> + [SEG6_ATTR_HMACKEYID] = { .type = NLA_U32, },
> + [SEG6_ATTR_SECRET] = { .type = NLA_BINARY, },
> + [SEG6_ATTR_SECRETLEN] = { .type = NLA_U8, },
> + [SEG6_ATTR_ALGID] = { .type = NLA_U8, },
> + [SEG6_ATTR_HMACINFO] = { .type = NLA_NESTED, },
> +};
> +
> +static struct genl_family seg6_genl_family = {
> + .id = GENL_ID_GENERATE,
> + .hdrsize = 0,
> + .name = SEG6_GENL_NAME,
> + .version = SEG6_GENL_VERSION,
> + .maxattr = SEG6_ATTR_MAX,
> + .netnsok = true,
> +};
> +
> +static int seg6_genl_sethmac(struct sk_buff *skb, struct genl_info *info)
> +{
> + return -ENOTSUPP;
> +}
> +
> +static int seg6_genl_set_tunsrc(struct sk_buff *skb, struct genl_info *info)
> +{
> + struct net *net = genl_info_net(info);
> + struct in6_addr *val, *t_old, *t_new;
> + struct seg6_pernet_data *sdata;
> +
> + sdata = seg6_pernet(net);
> +
> + if (!info->attrs[SEG6_ATTR_DST])
> + return -EINVAL;
> +
> + val = nla_data(info->attrs[SEG6_ATTR_DST]);
> + t_new = kmemdup(val, sizeof(*val), GFP_KERNEL);
> +
> + mutex_lock(&sdata->lock);
> +
> + t_old = sdata->tun_src;
> + rcu_assign_pointer(sdata->tun_src, t_new);
> +
> + mutex_unlock(&sdata->lock);
> +
> + synchronize_net();
> + kfree(t_old);
> +
> + return 0;
> +}
> +
> +static int seg6_genl_get_tunsrc(struct sk_buff *skb, struct genl_info *info)
> +{
> + struct net *net = genl_info_net(info);
> + struct in6_addr *tun_src;
> + struct sk_buff *msg;
> + void *hdr;
> +
> + msg = genlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
> + if (!msg)
> + return -ENOMEM;
> +
> + hdr = genlmsg_put(msg, info->snd_portid, info->snd_seq,
> + &seg6_genl_family, 0, SEG6_CMD_GET_TUNSRC);
> + if (!hdr)
> + goto free_msg;
> +
> + rcu_read_lock();
> + tun_src = rcu_dereference(seg6_pernet(net)->tun_src);
> +
> + if (nla_put(msg, SEG6_ATTR_DST, sizeof(struct in6_addr), tun_src))
> + goto nla_put_failure;
> +
> + rcu_read_unlock();
> +
> + genlmsg_end(msg, hdr);
> + genlmsg_reply(msg, info);
> +
> + return 0;
> +
> +nla_put_failure:
> + rcu_read_unlock();
> + genlmsg_cancel(msg, hdr);
> +free_msg:
> + nlmsg_free(msg);
> + return -ENOMEM;
> +}
> +
> +static int seg6_genl_dumphmac(struct sk_buff *skb, struct netlink_callback *cb)
> +{
> + return -ENOTSUPP;
> +}
> +
> +static const struct genl_ops seg6_genl_ops[] = {
> + {
> + .cmd = SEG6_CMD_SETHMAC,
> + .doit = seg6_genl_sethmac,
> + .policy = seg6_genl_policy,
> + .flags = GENL_ADMIN_PERM,
> + },
> + {
> + .cmd = SEG6_CMD_DUMPHMAC,
> + .dumpit = seg6_genl_dumphmac,
> + .policy = seg6_genl_policy,
> + .flags = GENL_ADMIN_PERM,
> + },
> + {
> + .cmd = SEG6_CMD_SET_TUNSRC,
> + .doit = seg6_genl_set_tunsrc,
> + .policy = seg6_genl_policy,
> + .flags = GENL_ADMIN_PERM,
> + },
> + {
> + .cmd = SEG6_CMD_GET_TUNSRC,
> + .doit = seg6_genl_get_tunsrc,
> + .policy = seg6_genl_policy,
> + .flags = GENL_ADMIN_PERM,
> + },
> +};
> +
> +static int __net_init seg6_net_init(struct net *net)
> +{
> + struct seg6_pernet_data *sdata;
> +
> + sdata = kzalloc(sizeof(*sdata), GFP_KERNEL);
> + if (!sdata)
> + return -ENOMEM;
> +
> + mutex_init(&sdata->lock);
> +
> + sdata->tun_src = kzalloc(sizeof(*sdata->tun_src), GFP_KERNEL);
> + if (!sdata->tun_src) {
> + kfree(sdata);
> + return -ENOMEM;
> + }
> +
> + net->ipv6.seg6_data = sdata;
> +
> + return 0;
> +}
> +
> +static void __net_exit seg6_net_exit(struct net *net)
> +{
> + struct seg6_pernet_data *sdata = seg6_pernet(net);
> +
> + kfree(sdata->tun_src);
> + kfree(sdata);
> +}
> +
> +static struct pernet_operations ip6_segments_ops = {
> + .init = seg6_net_init,
> + .exit = seg6_net_exit,
> +};
> +
> +static int __init seg6_init(void)
> +{
> + int err = -ENOMEM;
> +
> + err = genl_register_family_with_ops(&seg6_genl_family, seg6_genl_ops);
> + if (err)
> + goto out;
> +
> + err = register_pernet_subsys(&ip6_segments_ops);
> + if (err)
> + goto out_unregister_genl;
> +
> + pr_info("Segment Routing with IPv6\n");
> +
> +out:
> + return err;
> +out_unregister_genl:
> + genl_unregister_family(&seg6_genl_family);
> + goto out;
> +}
> +module_init(seg6_init);
> +
> +static void __exit seg6_exit(void)
> +{
> + unregister_pernet_subsys(&ip6_segments_ops);
> + genl_unregister_family(&seg6_genl_family);
> +}
> +module_exit(seg6_exit);
> +
> +MODULE_DESCRIPTION("Segment Routing with IPv6");
> +MODULE_LICENSE("GPL v2");
> --
> 2.7.3
>
Acked-by: Tom Herbert <tom@herbertland.com>
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v2 3/9] ipv6: sr: add support for SRH encapsulation and injection with lwtunnels
2016-10-26 15:54 ` [PATCH v2 3/9] ipv6: sr: add support for SRH encapsulation and injection with lwtunnels David Lebrun
@ 2016-10-28 2:56 ` Tom Herbert
0 siblings, 0 replies; 15+ messages in thread
From: Tom Herbert @ 2016-10-28 2:56 UTC (permalink / raw)
To: David Lebrun; +Cc: Linux Kernel Network Developers
On Wed, Oct 26, 2016 at 8:54 AM, David Lebrun <david.lebrun@uclouvain.be> wrote:
> This patch creates a new type of interfaceless lightweight tunnel (SEG6),
> enabling the encapsulation and injection of SRH within locally emitted
> packets and forwarded packets.
>
> From a configuration viewpoint, a seg6 tunnel would be configured as follows:
>
> ip -6 ro ad fc00::1/128 encap seg6 mode encap segs fc42::1,fc42::2,fc42::3 dev eth0
>
> Any packet whose destination address is fc00::1 would thus be encapsulated
> within an outer IPv6 header containing the SRH with three segments, and would
> actually be routed to the first segment of the list. If `mode inline' was
> specified instead of `mode encap', then the SRH would be directly inserted
> after the IPv6 header without outer encapsulation.
>
> Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
> ---
> include/linux/seg6_iptunnel.h | 6 +
> include/net/seg6.h | 1 +
> include/uapi/linux/lwtunnel.h | 1 +
> include/uapi/linux/seg6_iptunnel.h | 41 ++++
> net/core/lwtunnel.c | 2 +
> net/ipv6/Makefile | 2 +-
> net/ipv6/seg6_iptunnel.c | 370 +++++++++++++++++++++++++++++++++++++
> 7 files changed, 422 insertions(+), 1 deletion(-)
> create mode 100644 include/linux/seg6_iptunnel.h
> create mode 100644 include/uapi/linux/seg6_iptunnel.h
> create mode 100644 net/ipv6/seg6_iptunnel.c
>
> diff --git a/include/linux/seg6_iptunnel.h b/include/linux/seg6_iptunnel.h
> new file mode 100644
> index 0000000..5377cf6
> --- /dev/null
> +++ b/include/linux/seg6_iptunnel.h
> @@ -0,0 +1,6 @@
> +#ifndef _LINUX_SEG6_IPTUNNEL_H
> +#define _LINUX_SEG6_IPTUNNEL_H
> +
> +#include <uapi/linux/seg6_iptunnel.h>
> +
> +#endif
> diff --git a/include/net/seg6.h b/include/net/seg6.h
> index a9d9a9b..53d3bdb 100644
> --- a/include/net/seg6.h
> +++ b/include/net/seg6.h
> @@ -16,6 +16,7 @@
>
> #include <linux/net.h>
> #include <linux/ipv6.h>
> +#include <net/lwtunnel.h>
>
> struct seg6_pernet_data {
> struct mutex lock;
> diff --git a/include/uapi/linux/lwtunnel.h b/include/uapi/linux/lwtunnel.h
> index a478fe8..453cc62 100644
> --- a/include/uapi/linux/lwtunnel.h
> +++ b/include/uapi/linux/lwtunnel.h
> @@ -9,6 +9,7 @@ enum lwtunnel_encap_types {
> LWTUNNEL_ENCAP_IP,
> LWTUNNEL_ENCAP_ILA,
> LWTUNNEL_ENCAP_IP6,
> + LWTUNNEL_ENCAP_SEG6,
> __LWTUNNEL_ENCAP_MAX,
> };
>
> diff --git a/include/uapi/linux/seg6_iptunnel.h b/include/uapi/linux/seg6_iptunnel.h
> new file mode 100644
> index 0000000..da5524a
> --- /dev/null
> +++ b/include/uapi/linux/seg6_iptunnel.h
> @@ -0,0 +1,41 @@
> +/*
> + * SR-IPv6 implementation
> + *
> + * Author:
> + * David Lebrun <david.lebrun@uclouvain.be>
> + *
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * as published by the Free Software Foundation; either version
> + * 2 of the License, or (at your option) any later version.
> + */
> +
> +#ifndef _UAPI_LINUX_SEG6_IPTUNNEL_H
> +#define _UAPI_LINUX_SEG6_IPTUNNEL_H
> +
> +enum {
> + SEG6_IPTUNNEL_UNSPEC,
> + SEG6_IPTUNNEL_SRH,
> + __SEG6_IPTUNNEL_MAX,
> +};
> +#define SEG6_IPTUNNEL_MAX (__SEG6_IPTUNNEL_MAX - 1)
> +
> +struct seg6_iptunnel_encap {
> + int flags;
> + struct ipv6_sr_hdr srh[0];
> +};
> +
> +#define SEG6_IPTUN_ENCAP_SIZE(x) ((sizeof(*x)) + (((x)->srh->hdrlen + 1) << 3))
> +
> +#define SEG6_IPTUN_FLAG_ENCAP 0x1
> +
> +static inline size_t seg6_lwt_headroom(struct seg6_iptunnel_encap *tuninfo)
> +{
> + int encap = !!(tuninfo->flags & SEG6_IPTUN_FLAG_ENCAP);
> +
> + return ((tuninfo->srh->hdrlen + 1) << 3) +
> + (encap * sizeof(struct ipv6hdr));
> +}
> +
> +#endif
> diff --git a/net/core/lwtunnel.c b/net/core/lwtunnel.c
> index 88fd642..03976e9 100644
> --- a/net/core/lwtunnel.c
> +++ b/net/core/lwtunnel.c
> @@ -39,6 +39,8 @@ static const char *lwtunnel_encap_str(enum lwtunnel_encap_types encap_type)
> return "MPLS";
> case LWTUNNEL_ENCAP_ILA:
> return "ILA";
> + case LWTUNNEL_ENCAP_SEG6:
> + return "SEG6";
> case LWTUNNEL_ENCAP_IP6:
> case LWTUNNEL_ENCAP_IP:
> case LWTUNNEL_ENCAP_NONE:
> diff --git a/net/ipv6/Makefile b/net/ipv6/Makefile
> index 29a77d3..4bd1e73 100644
> --- a/net/ipv6/Makefile
> +++ b/net/ipv6/Makefile
> @@ -45,7 +45,7 @@ obj-$(CONFIG_IPV6_TUNNEL) += ip6_tunnel.o
> obj-$(CONFIG_IPV6_GRE) += ip6_gre.o
> obj-$(CONFIG_IPV6_FOU) += fou6.o
>
> -obj-y += addrconf_core.o exthdrs_core.o ip6_checksum.o ip6_icmp.o seg6.o
> +obj-y += addrconf_core.o exthdrs_core.o ip6_checksum.o ip6_icmp.o seg6.o seg6_iptunnel.o
> obj-$(CONFIG_INET) += output_core.o protocol.o $(ipv6-offload)
>
> obj-$(subst m,y,$(CONFIG_IPV6)) += inet6_hashtables.o
> diff --git a/net/ipv6/seg6_iptunnel.c b/net/ipv6/seg6_iptunnel.c
> new file mode 100644
> index 0000000..caae8ab
> --- /dev/null
> +++ b/net/ipv6/seg6_iptunnel.c
> @@ -0,0 +1,370 @@
> +/*
> + * SR-IPv6 implementation
> + *
> + * Author:
> + * David Lebrun <david.lebrun@uclouvain.be>
> + *
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * as published by the Free Software Foundation; either version
> + * 2 of the License, or (at your option) any later version.
> + */
> +
> +#include <linux/types.h>
> +#include <linux/skbuff.h>
> +#include <linux/net.h>
> +#include <linux/module.h>
> +#include <net/ip.h>
> +#include <net/lwtunnel.h>
> +#include <net/netevent.h>
> +#include <net/netns/generic.h>
> +#include <net/ip6_fib.h>
> +#include <net/route.h>
> +#include <net/seg6.h>
> +#include <linux/seg6.h>
> +#include <linux/seg6_iptunnel.h>
> +#include <net/addrconf.h>
> +#include <net/ip6_route.h>
> +#include <net/dst_cache.h>
> +
> +struct seg6_lwt {
> + struct dst_cache cache;
> + struct seg6_iptunnel_encap tuninfo[0];
> +};
> +
> +static inline struct seg6_lwt *seg6_lwt_lwtunnel(struct lwtunnel_state *lwt)
> +{
> + return (struct seg6_lwt *)lwt->data;
> +}
> +
> +static inline struct seg6_iptunnel_encap *
> +seg6_encap_lwtunnel(struct lwtunnel_state *lwt)
> +{
> + return seg6_lwt_lwtunnel(lwt)->tuninfo;
> +}
> +
> +static const struct nla_policy seg6_iptunnel_policy[SEG6_IPTUNNEL_MAX + 1] = {
> + [SEG6_IPTUNNEL_SRH] = { .type = NLA_BINARY },
> +};
> +
> +int nla_put_srh(struct sk_buff *skb, int attrtype,
> + struct seg6_iptunnel_encap *tuninfo)
> +{
> + struct seg6_iptunnel_encap *data;
> + struct nlattr *nla;
> + int len;
> +
> + len = SEG6_IPTUN_ENCAP_SIZE(tuninfo);
> +
> + nla = nla_reserve(skb, attrtype, len);
> + if (!nla)
> + return -EMSGSIZE;
> +
> + data = nla_data(nla);
> + memcpy(data, tuninfo, len);
> +
> + return 0;
> +}
> +
> +static void set_tun_src(struct net *net, struct net_device *dev,
> + struct in6_addr *daddr, struct in6_addr *saddr)
> +{
> + struct seg6_pernet_data *sdata = seg6_pernet(net);
> + struct in6_addr *tun_src;
> +
> + rcu_read_lock();
> +
> + tun_src = rcu_dereference(sdata->tun_src);
> +
> + if (!ipv6_addr_any(tun_src)) {
> + memcpy(saddr, tun_src, sizeof(struct in6_addr));
> + } else {
> + ipv6_dev_get_saddr(net, dev, daddr, IPV6_PREFER_SRC_PUBLIC,
> + saddr);
> + }
> +
> + rcu_read_unlock();
> +}
> +
> +/* encapsulate an IPv6 packet within an outer IPv6 header with a given SRH */
> +static int seg6_do_srh_encap(struct sk_buff *skb, struct ipv6_sr_hdr *osrh)
> +{
> + struct net *net = dev_net(skb_dst(skb)->dev);
> + struct ipv6hdr *hdr, *inner_hdr;
> + struct ipv6_sr_hdr *isrh;
> + int hdrlen, tot_len, err;
> +
> + hdrlen = (osrh->hdrlen + 1) << 3;
> + tot_len = hdrlen + sizeof(*hdr);
> +
> + err = pskb_expand_head(skb, tot_len, 0, GFP_ATOMIC);
> + if (unlikely(err))
> + return err;
> +
> + inner_hdr = ipv6_hdr(skb);
> +
> + skb_push(skb, tot_len);
> + skb_reset_network_header(skb);
> + skb_mac_header_rebuild(skb);
> + hdr = ipv6_hdr(skb);
> +
> + /* inherit tc, flowlabel and hlim
> + * hlim will be decremented in ip6_forward() afterwards and
> + * decapsulation will overwrite inner hlim with outer hlim
> + */
> + ip6_flow_hdr(hdr, ip6_tclass(ip6_flowinfo(inner_hdr)),
> + ip6_flowlabel(inner_hdr));
> + hdr->hop_limit = inner_hdr->hop_limit;
> + hdr->nexthdr = NEXTHDR_ROUTING;
> +
> + isrh = (void *)hdr + sizeof(*hdr);
> + memcpy(isrh, osrh, hdrlen);
> +
> + isrh->nexthdr = NEXTHDR_IPV6;
> +
> + hdr->daddr = isrh->segments[isrh->first_segment];
> + set_tun_src(net, skb->dev, &hdr->daddr, &hdr->saddr);
> +
> + skb_postpush_rcsum(skb, hdr, tot_len);
> +
> + return 0;
> +}
> +
> +/* insert an SRH within an IPv6 packet, just after the IPv6 header */
> +static int seg6_do_srh_inline(struct sk_buff *skb, struct ipv6_sr_hdr *osrh)
> +{
> + struct ipv6hdr *hdr, *oldhdr;
> + struct ipv6_sr_hdr *isrh;
> + int hdrlen, err;
> +
> + hdrlen = (osrh->hdrlen + 1) << 3;
> +
> + err = pskb_expand_head(skb, hdrlen, 0, GFP_ATOMIC);
> + if (unlikely(err))
> + return err;
> +
> + oldhdr = ipv6_hdr(skb);
> +
> + skb_pull(skb, sizeof(struct ipv6hdr));
> + skb_postpull_rcsum(skb, skb_network_header(skb),
> + sizeof(struct ipv6hdr));
> +
> + skb_push(skb, sizeof(struct ipv6hdr) + hdrlen);
> + skb_reset_network_header(skb);
> + skb_mac_header_rebuild(skb);
> +
> + hdr = ipv6_hdr(skb);
> +
> + memmove(hdr, oldhdr, sizeof(*hdr));
> +
> + isrh = (void *)hdr + sizeof(*hdr);
> + memcpy(isrh, osrh, hdrlen);
> +
> + isrh->nexthdr = hdr->nexthdr;
> + hdr->nexthdr = NEXTHDR_ROUTING;
> +
> + isrh->segments[0] = hdr->daddr;
> + hdr->daddr = isrh->segments[isrh->first_segment];
> +
> + skb_postpush_rcsum(skb, hdr, sizeof(struct ipv6hdr) + hdrlen);
> +
> + return 0;
> +}
> +
> +static int seg6_do_srh(struct sk_buff *skb)
> +{
> + struct dst_entry *dst = skb_dst(skb);
> + struct seg6_iptunnel_encap *tinfo;
> + int err = 0;
> +
> + tinfo = seg6_encap_lwtunnel(dst->lwtstate);
> +
> + if (likely(!skb->encapsulation)) {
> + skb_reset_inner_headers(skb);
> + skb->encapsulation = 1;
> + }
> +
> + if (tinfo->flags & SEG6_IPTUN_FLAG_ENCAP) {
> + err = seg6_do_srh_encap(skb, tinfo->srh);
> + } else {
> + err = seg6_do_srh_inline(skb, tinfo->srh);
> + skb_reset_inner_headers(skb);
> + }
> +
> + if (err)
> + return err;
> +
> + ipv6_hdr(skb)->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
> + skb_set_transport_header(skb, sizeof(struct ipv6hdr));
> +
> + skb_set_inner_protocol(skb, skb->protocol);
> +
> + return 0;
> +}
> +
> +int seg6_input(struct sk_buff *skb)
> +{
> + int err;
> +
> + err = seg6_do_srh(skb);
> + if (unlikely(err)) {
> + kfree_skb(skb);
> + return err;
> + }
> +
> + skb_dst_drop(skb);
> + ip6_route_input(skb);
> +
> + return dst_input(skb);
> +}
> +
> +int seg6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
> +{
> + struct dst_entry *orig_dst = skb_dst(skb);
> + struct seg6_lwt *slwt;
> + struct dst_entry *dst;
> + int err = -EINVAL;
> +
> + err = seg6_do_srh(skb);
> + if (unlikely(err))
> + goto drop;
> +
> + slwt = seg6_lwt_lwtunnel(orig_dst->lwtstate);
> +
> + dst = dst_cache_get(&slwt->cache);
> + if (unlikely(!dst)) {
> + struct ipv6hdr *hdr = ipv6_hdr(skb);
> + struct flowi6 fl6;
> +
> + fl6.daddr = hdr->daddr;
> + fl6.saddr = hdr->saddr;
> + fl6.flowlabel = ip6_flowinfo(hdr);
> + fl6.flowi6_mark = skb->mark;
> + fl6.flowi6_proto = hdr->nexthdr;
> +
> + dst = ip6_route_output(net, NULL, &fl6);
> + if (dst->error) {
> + err = dst->error;
> + dst_release(dst);
> + goto drop;
> + }
> +
> + dst_cache_set_ip6(&slwt->cache, dst, &fl6.saddr);
> + }
> +
> + skb_dst_drop(skb);
> + skb_dst_set(skb, dst);
> +
> + return dst_output(net, sk, skb);
> +drop:
> + kfree_skb(skb);
> + return err;
> +}
> +
> +static int seg6_build_state(struct net_device *dev, struct nlattr *nla,
> + unsigned int family, const void *cfg,
> + struct lwtunnel_state **ts)
> +{
> + struct nlattr *tb[SEG6_IPTUNNEL_MAX + 1];
> + struct seg6_iptunnel_encap *tuninfo;
> + struct lwtunnel_state *newts;
> + struct seg6_lwt *slwt;
> + int tuninfo_len;
> + int err;
> +
> + err = nla_parse_nested(tb, SEG6_IPTUNNEL_MAX, nla,
> + seg6_iptunnel_policy);
> +
> + if (err < 0)
> + return err;
> +
> + if (!tb[SEG6_IPTUNNEL_SRH])
> + return -EINVAL;
> +
> + tuninfo = nla_data(tb[SEG6_IPTUNNEL_SRH]);
> + tuninfo_len = SEG6_IPTUN_ENCAP_SIZE(tuninfo);
> +
> + newts = lwtunnel_state_alloc(tuninfo_len + sizeof(*slwt));
> + if (!newts)
> + return -ENOMEM;
> +
> + slwt = seg6_lwt_lwtunnel(newts);
> +
> + err = dst_cache_init(&slwt->cache, GFP_KERNEL);
> + if (err) {
> + kfree(newts);
> + return err;
> + }
> +
> + memcpy(&slwt->tuninfo, tuninfo, tuninfo_len);
> +
> + newts->type = LWTUNNEL_ENCAP_SEG6;
> + newts->flags |= LWTUNNEL_STATE_OUTPUT_REDIRECT |
> + LWTUNNEL_STATE_INPUT_REDIRECT;
> + newts->headroom = seg6_lwt_headroom(tuninfo);
> +
> + *ts = newts;
> +
> + return 0;
> +}
> +
> +static void seg6_destroy_state(struct lwtunnel_state *lwt)
> +{
> + dst_cache_destroy(&seg6_lwt_lwtunnel(lwt)->cache);
> +}
> +
> +static int seg6_fill_encap_info(struct sk_buff *skb,
> + struct lwtunnel_state *lwtstate)
> +{
> + struct seg6_iptunnel_encap *tuninfo = seg6_encap_lwtunnel(lwtstate);
> +
> + if (nla_put_srh(skb, SEG6_IPTUNNEL_SRH, tuninfo))
> + return -EMSGSIZE;
> +
> + return 0;
> +}
> +
> +static int seg6_encap_nlsize(struct lwtunnel_state *lwtstate)
> +{
> + struct seg6_iptunnel_encap *tuninfo = seg6_encap_lwtunnel(lwtstate);
> +
> + return nla_total_size(SEG6_IPTUN_ENCAP_SIZE(tuninfo));
> +}
> +
> +static int seg6_encap_cmp(struct lwtunnel_state *a, struct lwtunnel_state *b)
> +{
> + struct seg6_iptunnel_encap *a_hdr = seg6_encap_lwtunnel(a);
> + struct seg6_iptunnel_encap *b_hdr = seg6_encap_lwtunnel(b);
> + int len = SEG6_IPTUN_ENCAP_SIZE(a_hdr);
> +
> + if (len != SEG6_IPTUN_ENCAP_SIZE(b_hdr))
> + return 1;
> +
> + return memcmp(a_hdr, b_hdr, len);
> +}
> +
> +static const struct lwtunnel_encap_ops seg6_iptun_ops = {
> + .build_state = seg6_build_state,
> + .destroy_state = seg6_destroy_state,
> + .output = seg6_output,
> + .input = seg6_input,
> + .fill_encap = seg6_fill_encap_info,
> + .get_encap_size = seg6_encap_nlsize,
> + .cmp_encap = seg6_encap_cmp,
> +};
> +
> +static int __init seg6_iptunnel_init(void)
> +{
> + return lwtunnel_encap_add_ops(&seg6_iptun_ops, LWTUNNEL_ENCAP_SEG6);
> +}
> +module_init(seg6_iptunnel_init);
> +
> +static void __exit seg6_iptunnel_exit(void)
> +{
> + lwtunnel_encap_del_ops(&seg6_iptun_ops, LWTUNNEL_ENCAP_SEG6);
> +}
> +module_exit(seg6_iptunnel_exit);
> +
> +MODULE_DESCRIPTION("Segment Routing with IPv6 IP Tunnels");
> +MODULE_LICENSE("GPL v2");
> --
> 2.7.3
>
Looks good.
Acked-by: Tom Herbert <tom@herbertland.com>
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v2 4/9] ipv6: sr: add core files for SR HMAC support
2016-10-26 15:54 ` [PATCH v2 4/9] ipv6: sr: add core files for SR HMAC support David Lebrun
@ 2016-10-28 3:05 ` Tom Herbert
0 siblings, 0 replies; 15+ messages in thread
From: Tom Herbert @ 2016-10-28 3:05 UTC (permalink / raw)
To: David Lebrun; +Cc: Linux Kernel Network Developers
On Wed, Oct 26, 2016 at 8:54 AM, David Lebrun <david.lebrun@uclouvain.be> wrote:
> This patch adds the necessary functions to compute and check the HMAC signature
> of an SR-enabled packet. Two HMAC algorithms are supported: hmac(sha1) and
> hmac(sha256).
>
> In order to avoid dynamic memory allocation for each HMAC computation,
> a per-cpu ring buffer is allocated for this purpose.
>
> Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
> ---
> include/linux/seg6_hmac.h | 6 +
> include/net/seg6_hmac.h | 61 ++++++
> include/uapi/linux/seg6_hmac.h | 20 ++
> net/ipv6/Kconfig | 12 ++
> net/ipv6/seg6_hmac.c | 432 +++++++++++++++++++++++++++++++++++++++++
> 5 files changed, 531 insertions(+)
> create mode 100644 include/linux/seg6_hmac.h
> create mode 100644 include/net/seg6_hmac.h
> create mode 100644 include/uapi/linux/seg6_hmac.h
> create mode 100644 net/ipv6/seg6_hmac.c
>
> diff --git a/include/linux/seg6_hmac.h b/include/linux/seg6_hmac.h
> new file mode 100644
> index 0000000..da437eb
> --- /dev/null
> +++ b/include/linux/seg6_hmac.h
> @@ -0,0 +1,6 @@
> +#ifndef _LINUX_SEG6_HMAC_H
> +#define _LINUX_SEG6_HMAC_H
> +
> +#include <uapi/linux/seg6_hmac.h>
> +
> +#endif
> diff --git a/include/net/seg6_hmac.h b/include/net/seg6_hmac.h
> new file mode 100644
> index 0000000..6e5ee6a
> --- /dev/null
> +++ b/include/net/seg6_hmac.h
> @@ -0,0 +1,61 @@
> +/*
> + * SR-IPv6 implementation
> + *
> + * Author:
> + * David Lebrun <david.lebrun@uclouvain.be>
> + *
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * as published by the Free Software Foundation; either version
> + * 2 of the License, or (at your option) any later version.
> + */
> +
> +#ifndef _NET_SEG6_HMAC_H
> +#define _NET_SEG6_HMAC_H
> +
> +#include <net/flow.h>
> +#include <net/ip6_fib.h>
> +#include <net/sock.h>
> +#include <linux/ip.h>
> +#include <linux/ipv6.h>
> +#include <linux/route.h>
> +#include <net/seg6.h>
> +#include <linux/seg6_hmac.h>
> +
> +#define SEG6_HMAC_MAX_DIGESTSIZE 160
> +#define SEG6_HMAC_RING_SIZE 256
> +
> +struct seg6_hmac_info {
> + struct list_head list;
> +
> + u32 hmackeyid;
> + char secret[SEG6_HMAC_SECRET_LEN];
> + u8 slen;
> + u8 alg_id;
> +};
> +
> +struct seg6_hmac_algo {
> + u8 alg_id;
> + char name[64];
> + struct crypto_shash * __percpu *tfms;
> + struct shash_desc * __percpu *shashs;
> +};
> +
> +extern int seg6_hmac_compute(struct seg6_hmac_info *hinfo,
> + struct ipv6_sr_hdr *hdr, struct in6_addr *saddr,
> + u8 *output);
> +extern struct seg6_hmac_info *seg6_hmac_info_lookup(struct net *net, u32 key);
> +extern int seg6_hmac_info_add(struct net *net, u32 key,
> + struct seg6_hmac_info *hinfo);
> +extern int seg6_hmac_info_del(struct net *net, u32 key,
> + struct seg6_hmac_info *hinfo);
> +extern int seg6_push_hmac(struct net *net, struct in6_addr *saddr,
> + struct ipv6_sr_hdr *srh);
> +extern bool seg6_hmac_validate_skb(struct sk_buff *skb);
> +extern int seg6_hmac_init(void);
> +extern void seg6_hmac_exit(void);
> +extern int seg6_hmac_net_init(struct net *net);
> +extern void seg6_hmac_net_exit(struct net *net);
> +
> +#endif
> diff --git a/include/uapi/linux/seg6_hmac.h b/include/uapi/linux/seg6_hmac.h
> new file mode 100644
> index 0000000..0b5eda7
> --- /dev/null
> +++ b/include/uapi/linux/seg6_hmac.h
> @@ -0,0 +1,20 @@
> +#ifndef _UAPI_LINUX_SEG6_HMAC_H
> +#define _UAPI_LINUX_SEG6_HMAC_H
> +
> +#define SEG6_HMAC_SECRET_LEN 64
> +#define SEG6_HMAC_FIELD_LEN 32
> +
> +struct sr6_tlv_hmac {
> + __u8 type;
> + __u8 len;
> + __u16 reserved;
Maybe add a common definition for SR TLV.
> + __be32 hmackeyid;
> + __u8 hmac[SEG6_HMAC_FIELD_LEN];
> +} __attribute__((packed));
> +
> +enum {
> + SEG6_HMAC_ALGO_SHA1 = 1,
> + SEG6_HMAC_ALGO_SHA256 = 2,
> +};
> +
> +#endif
> diff --git a/net/ipv6/Kconfig b/net/ipv6/Kconfig
> index 2343e4f..c647712 100644
> --- a/net/ipv6/Kconfig
> +++ b/net/ipv6/Kconfig
> @@ -289,4 +289,16 @@ config IPV6_PIMSM_V2
> Support for IPv6 PIM multicast routing protocol PIM-SMv2.
> If unsure, say N.
>
> +config IPV6_SEG6_HMAC
> + bool "IPv6: Segment Routing HMAC support"
> + depends on IPV6
> + select CRYPTO_HMAC
> + select CRYPTO_SHA1
> + select CRYPTO_SHA256
> + ---help---
> + Support for HMAC signature generation and verification
> + of SR-enabled packets.
> +
> + If unsure, say N.
> +
> endif # IPV6
> diff --git a/net/ipv6/seg6_hmac.c b/net/ipv6/seg6_hmac.c
> new file mode 100644
> index 0000000..65ebc0c
> --- /dev/null
> +++ b/net/ipv6/seg6_hmac.c
> @@ -0,0 +1,432 @@
> +/*
> + * SR-IPv6 implementation -- HMAC functions
> + *
> + * Author:
> + * David Lebrun <david.lebrun@uclouvain.be>
> + *
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * as published by the Free Software Foundation; either version
> + * 2 of the License, or (at your option) any later version.
> + */
> +
> +#include <linux/errno.h>
> +#include <linux/types.h>
> +#include <linux/socket.h>
> +#include <linux/sockios.h>
> +#include <linux/net.h>
> +#include <linux/netdevice.h>
> +#include <linux/in6.h>
> +#include <linux/icmpv6.h>
> +#include <linux/mroute6.h>
> +#include <linux/slab.h>
> +
> +#include <linux/netfilter.h>
> +#include <linux/netfilter_ipv6.h>
> +
> +#include <net/sock.h>
> +#include <net/snmp.h>
> +
> +#include <net/ipv6.h>
> +#include <net/protocol.h>
> +#include <net/transp_v6.h>
> +#include <net/rawv6.h>
> +#include <net/ndisc.h>
> +#include <net/ip6_route.h>
> +#include <net/addrconf.h>
> +#include <net/xfrm.h>
> +
> +#include <linux/cryptohash.h>
> +#include <crypto/hash.h>
> +#include <crypto/sha.h>
> +#include <net/seg6.h>
> +#include <net/genetlink.h>
> +#include <net/seg6_hmac.h>
> +#include <linux/random.h>
> +
> +static char * __percpu *hmac_ring;
> +
> +static struct seg6_hmac_algo hmac_algos[] = {
> + {
> + .alg_id = SEG6_HMAC_ALGO_SHA1,
> + .name = "hmac(sha1)",
> + },
> + {
> + .alg_id = SEG6_HMAC_ALGO_SHA256,
> + .name = "hmac(sha256)",
> + },
> +};
> +
> +static struct seg6_hmac_algo *__hmac_get_algo(u8 alg_id)
> +{
> + struct seg6_hmac_algo *algo;
> + int i, alg_count;
> +
> + alg_count = sizeof(hmac_algos) / sizeof(struct seg6_hmac_algo);
> + for (i = 0; i < alg_count; i++) {
> + algo = &hmac_algos[i];
> + if (algo->alg_id == alg_id)
> + return algo;
> + }
> +
> + return NULL;
> +}
> +
> +static int __do_hmac(struct seg6_hmac_info *hinfo, const char *text, u8 psize,
> + u8 *output, int outlen)
> +{
> + struct seg6_hmac_algo *algo;
> + struct crypto_shash *tfm;
> + struct shash_desc *shash;
> + int ret, dgsize;
> +
> + algo = __hmac_get_algo(hinfo->alg_id);
> + if (!algo)
> + return -ENOENT;
> +
> + tfm = *this_cpu_ptr(algo->tfms);
> +
> + dgsize = crypto_shash_digestsize(tfm);
> + if (dgsize > outlen) {
> + pr_debug("sr-ipv6: __do_hmac: digest size too big (%d / %d)\n",
> + dgsize, outlen);
> + return -ENOMEM;
> + }
> +
> + ret = crypto_shash_setkey(tfm, hinfo->secret, hinfo->slen);
> + if (ret < 0) {
> + pr_debug("sr-ipv6: crypto_shash_setkey failed: err %d\n", ret);
> + goto failed;
> + }
> +
> + shash = *this_cpu_ptr(algo->shashs);
> + shash->tfm = tfm;
> +
> + ret = crypto_shash_digest(shash, text, psize, output);
> + if (ret < 0) {
> + pr_debug("sr-ipv6: crypto_shash_digest failed: err %d\n", ret);
> + goto failed;
> + }
> +
> + return dgsize;
> +
> +failed:
> + return ret;
> +}
> +
> +int seg6_hmac_compute(struct seg6_hmac_info *hinfo, struct ipv6_sr_hdr *hdr,
> + struct in6_addr *saddr, u8 *output)
> +{
> + __be32 hmackeyid = cpu_to_be32(hinfo->hmackeyid);
> + u8 tmp_out[SEG6_HMAC_MAX_DIGESTSIZE];
> + int plen, i, dgsize, wrsize;
> + char *ring, *off;
> +
> + /* a 160-byte buffer for digest output allows to store highest known
> + * hash function (RadioGatun) with up to 1216 bits
> + */
> +
> + /* saddr(16) + first_seg(1) + cleanup(1) + keyid(4) + seglist(16n) */
> + plen = 16 + 1 + 1 + 4 + (hdr->first_segment + 1) * 16;
> +
> + /* this limit allows for 14 segments */
> + if (plen >= SEG6_HMAC_RING_SIZE)
> + return -EMSGSIZE;
> +
> + local_bh_disable();
> + ring = *this_cpu_ptr(hmac_ring);
> + off = ring;
> + memcpy(off, saddr, 16);
> + off += 16;
> + *off++ = hdr->first_segment;
> + *off++ = !!(sr_has_cleanup(hdr)) << 7;
> + memcpy(off, &hmackeyid, 4);
> + off += 4;
> +
It's not clear what is being done here. Comment might be nice.
> + for (i = 0; i < hdr->first_segment + 1; i++) {
> + memcpy(off, hdr->segments + i, 16);
> + off += 16;
> + }
> +
> + dgsize = __do_hmac(hinfo, ring, plen, tmp_out,
> + SEG6_HMAC_MAX_DIGESTSIZE);
> + local_bh_enable();
> +
> + if (dgsize < 0)
> + return dgsize;
> +
> + wrsize = SEG6_HMAC_FIELD_LEN;
> + if (wrsize > dgsize)
> + wrsize = dgsize;
> +
> + memset(output, 0, SEG6_HMAC_FIELD_LEN);
> + memcpy(output, tmp_out, wrsize);
> +
> + return 0;
> +}
> +EXPORT_SYMBOL(seg6_hmac_compute);
> +
> +/* checks if an incoming SR-enabled packet's HMAC status matches
> + * the incoming policy.
> + *
> + * called with rcu_read_lock()
> + */
> +bool seg6_hmac_validate_skb(struct sk_buff *skb)
> +{
> + u8 hmac_output[SEG6_HMAC_FIELD_LEN];
> + struct net *net = dev_net(skb->dev);
> + struct seg6_hmac_info *hinfo;
> + struct sr6_tlv_hmac *tlv;
> + struct ipv6_sr_hdr *srh;
> + struct inet6_dev *idev;
> +
> + idev = __in6_dev_get(skb->dev);
> +
> + srh = (struct ipv6_sr_hdr *)skb_transport_header(skb);
> +
> + tlv = seg6_get_tlv_hmac(srh);
> +
> + /* mandatory check but no tlv */
> + if (idev->cnf.seg6_require_hmac > 0 && !tlv)
> + return false;
> +
> + /* no check */
> + if (idev->cnf.seg6_require_hmac < 0)
> + return true;
> +
> + /* check only if present */
> + if (idev->cnf.seg6_require_hmac == 0 && !tlv)
> + return true;
> +
> + /* now, seg6_require_hmac >= 0 && tlv */
> +
> + hinfo = seg6_hmac_info_lookup(net, be32_to_cpu(tlv->hmackeyid));
> + if (!hinfo)
> + return false;
> +
> + if (seg6_hmac_compute(hinfo, srh, &ipv6_hdr(skb)->saddr, hmac_output))
> + return false;
> +
> + if (memcmp(hmac_output, tlv->hmac, SEG6_HMAC_FIELD_LEN) != 0)
> + return false;
> +
> + return true;
> +}
> +
> +/* called with rcu_read_lock() */
> +struct seg6_hmac_info *seg6_hmac_info_lookup(struct net *net, u32 key)
> +{
> + struct seg6_pernet_data *sdata = seg6_pernet(net);
> + struct seg6_hmac_info *hinfo;
> +
Linked list? Is this something that should have a hash table.
> + list_for_each_entry_rcu(hinfo, &sdata->hmac_infos, list) {
> + if (hinfo->hmackeyid == key)
> + return hinfo;
> + }
> +
> + return NULL;
> +}
> +EXPORT_SYMBOL(seg6_hmac_info_lookup);
> +
> +int seg6_hmac_info_add(struct net *net, u32 key, struct seg6_hmac_info *hinfo)
> +{
> + struct seg6_pernet_data *sdata = seg6_pernet(net);
> + struct seg6_hmac_info *old_hinfo;
> +
> + old_hinfo = seg6_hmac_info_lookup(net, key);
> + if (old_hinfo)
> + return -EEXIST;
> +
> + list_add_rcu(&hinfo->list, &sdata->hmac_infos);
> +
> + return 0;
> +}
> +EXPORT_SYMBOL(seg6_hmac_info_add);
> +
> +int seg6_hmac_info_del(struct net *net, u32 key, struct seg6_hmac_info *hinfo)
> +{
> + struct seg6_hmac_info *tmp;
> +
> + tmp = seg6_hmac_info_lookup(net, key);
> + if (!tmp)
> + return -ENOENT;
> +
> + /* entry was replaced, ignore deletion */
> + if (tmp != hinfo)
> + return -ENOENT;
> +
> + list_del_rcu(&hinfo->list);
> + synchronize_net();
> +
> + return 0;
> +}
> +EXPORT_SYMBOL(seg6_hmac_info_del);
> +
> +static void seg6_hmac_info_flush(struct net *net)
> +{
> + struct seg6_pernet_data *sdata = seg6_pernet(net);
> + struct seg6_hmac_info *hinfo;
> +
> + mutex_lock(&sdata->lock);
> + while ((hinfo = list_first_or_null_rcu(&sdata->hmac_infos,
> + struct seg6_hmac_info,
> + list)) != NULL) {
> + list_del_rcu(&hinfo->list);
> + mutex_unlock(&sdata->lock);
> + synchronize_net();
> + kfree(hinfo);
> + mutex_lock(&sdata->lock);
> + }
> +
> + mutex_unlock(&sdata->lock);
> +}
> +
> +int seg6_push_hmac(struct net *net, struct in6_addr *saddr,
> + struct ipv6_sr_hdr *srh)
> +{
> + struct seg6_hmac_info *hinfo;
> + struct sr6_tlv_hmac *tlv;
> + int err = -ENOENT;
> +
> + tlv = seg6_get_tlv_hmac(srh);
> + if (!tlv)
> + return -EINVAL;
> +
> + rcu_read_lock();
> +
> + hinfo = seg6_hmac_info_lookup(net, be32_to_cpu(tlv->hmackeyid));
> + if (!hinfo)
> + goto out;
> +
> + memset(tlv->hmac, 0, SEG6_HMAC_FIELD_LEN);
> + err = seg6_hmac_compute(hinfo, srh, saddr, tlv->hmac);
> +
> +out:
> + rcu_read_unlock();
> + return err;
> +}
> +EXPORT_SYMBOL(seg6_push_hmac);
> +
> +static int seg6_hmac_init_ring(void)
> +{
> + int i;
> +
> + hmac_ring = alloc_percpu(char *);
> +
> + if (!hmac_ring)
> + return -ENOMEM;
> +
> + for_each_possible_cpu(i) {
> + char *ring = kzalloc(SEG6_HMAC_RING_SIZE, GFP_KERNEL);
> +
> + if (!ring)
> + return -ENOMEM;
> +
> + *per_cpu_ptr(hmac_ring, i) = ring;
> + }
> +
> + return 0;
> +}
> +
> +static int seg6_hmac_init_algo(void)
> +{
> + struct seg6_hmac_algo *algo;
> + struct crypto_shash *tfm;
> + struct shash_desc *shash;
> + int i, alg_count, cpu;
> +
> + alg_count = sizeof(hmac_algos) / sizeof(struct seg6_hmac_algo);
> +
> + for (i = 0; i < alg_count; i++) {
> + struct crypto_shash **p_tfm;
> + int shsize;
> +
> + algo = &hmac_algos[i];
> + algo->tfms = alloc_percpu(struct crypto_shash *);
> + if (!algo->tfms)
> + return -ENOMEM;
> +
> + for_each_possible_cpu(cpu) {
> + tfm = crypto_alloc_shash(algo->name, 0, GFP_KERNEL);
> + if (IS_ERR(tfm))
> + return PTR_ERR(tfm);
> + p_tfm = per_cpu_ptr(algo->tfms, cpu);
> + *p_tfm = tfm;
> + }
> +
> + p_tfm = this_cpu_ptr(algo->tfms);
> + tfm = *p_tfm;
> +
> + shsize = sizeof(*shash) + crypto_shash_descsize(tfm);
> +
> + algo->shashs = alloc_percpu(struct shash_desc *);
> + if (!algo->shashs)
> + return -ENOMEM;
> +
> + for_each_possible_cpu(cpu) {
> + shash = kzalloc(shsize, GFP_KERNEL);
> + if (!shash)
> + return -ENOMEM;
> + *per_cpu_ptr(algo->shashs, cpu) = shash;
> + }
> + }
> +
> + return 0;
> +}
> +
> +int __init seg6_hmac_init(void)
> +{
> + int ret;
> +
> + ret = seg6_hmac_init_ring();
> + if (ret < 0)
> + goto out;
> +
> + ret = seg6_hmac_init_algo();
> +
> +out:
> + return ret;
> +}
> +
> +int __net_init seg6_hmac_net_init(struct net *net)
> +{
> + struct seg6_pernet_data *sdata = seg6_pernet(net);
> +
> + INIT_LIST_HEAD(&sdata->hmac_infos);
> + return 0;
> +}
> +
> +void __exit seg6_hmac_exit(void)
> +{
> + struct seg6_hmac_algo *algo = NULL;
> + int i, alg_count, cpu;
> +
> + for_each_possible_cpu(i) {
> + char *ring = *per_cpu_ptr(hmac_ring, i);
> +
> + kfree(ring);
> + }
> + free_percpu(hmac_ring);
> +
> + alg_count = sizeof(hmac_algos) / sizeof(struct seg6_hmac_algo);
> + for (i = 0; i < alg_count; i++) {
> + algo = &hmac_algos[i];
> + for_each_possible_cpu(cpu) {
> + struct crypto_shash *tfm;
> + struct shash_desc *shash;
> +
> + shash = *per_cpu_ptr(algo->shashs, cpu);
> + kfree(shash);
> + tfm = *per_cpu_ptr(algo->tfms, cpu);
> + crypto_free_shash(tfm);
> + }
> + free_percpu(algo->tfms);
> + free_percpu(algo->shashs);
> + }
> +}
> +
> +void __net_exit seg6_hmac_net_exit(struct net *net)
> +{
> + seg6_hmac_info_flush(net);
> +}
This is pretty complex stuff. It would be great to generalize this
somehow in a library (maybe a future task). I am updating GUE to use
the same algorithm for HMAC so would be nice to share.
> --
> 2.7.3
>
^ permalink raw reply [flat|nested] 15+ messages in thread
end of thread, other threads:[~2016-10-28 3:58 UTC | newest]
Thread overview: 15+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2016-10-26 15:54 [PATCH v2 0/9] net: add support for IPv6 Segment Routing David Lebrun
2016-10-26 15:54 ` [PATCH v2 1/9] ipv6: implement dataplane support for rthdr type 4 (Segment Routing Header) David Lebrun
2016-10-28 2:50 ` Tom Herbert
2016-10-26 15:54 ` [PATCH v2 2/9] ipv6: sr: add code base for control plane support of SR-IPv6 David Lebrun
2016-10-28 2:52 ` Tom Herbert
2016-10-26 15:54 ` [PATCH v2 3/9] ipv6: sr: add support for SRH encapsulation and injection with lwtunnels David Lebrun
2016-10-28 2:56 ` Tom Herbert
2016-10-26 15:54 ` [PATCH v2 4/9] ipv6: sr: add core files for SR HMAC support David Lebrun
2016-10-28 3:05 ` Tom Herbert
2016-10-26 15:56 ` [PATCH v2 5/9] ipv6: sr: implement API to control SR HMAC structure David Lebrun
2016-10-26 15:56 ` [PATCH v2 6/9] ipv6: sr: add calls to verify and insert HMAC signatures David Lebrun
2016-10-26 15:56 ` [PATCH v2 7/9] ipv6: add source address argument for ipv6_push_nfrag_opts David Lebrun
2016-10-26 15:56 ` [PATCH v2 8/9] ipv6: sr: add support for SRH injection through setsockopt David Lebrun
2016-10-26 15:56 ` [PATCH v2 9/9] ipv6: sr: add documentation file for per-interface sysctls David Lebrun
2016-10-26 16:03 ` [PATCH v2 0/9] net: add support for IPv6 Segment Routing David Lebrun
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).