* [PATCH bpf-next v9 0/9] bpf: getsockopt and setsockopt hooks
@ 2019-06-27 20:38 Stanislav Fomichev
2019-06-27 20:38 ` [PATCH bpf-next v9 1/9] bpf: implement " Stanislav Fomichev
` (9 more replies)
0 siblings, 10 replies; 13+ messages in thread
From: Stanislav Fomichev @ 2019-06-27 20:38 UTC (permalink / raw)
To: netdev, bpf; +Cc: davem, ast, daniel, Stanislav Fomichev
This series implements two new per-cgroup hooks: getsockopt and
setsockopt along with a new sockopt program type. The idea is pretty
similar to recently introduced cgroup sysctl hooks, but
implementation is simpler (no need to convert to/from strings).
What this can be applied to:
* move business logic of what tos/priority/etc can be set by
containers (either pass or reject)
* handle existing options (or introduce new ones) differently by
propagating some information in cgroup/socket local storage
Compared to a simple syscall/{g,s}etsockopt tracepoint, those
hooks are context aware. Meaning, they can access underlying socket
and use cgroup and socket local storage.
v9:
* allow overwriting setsocktop arguments (Alexei Starovoitov)
(see individual changes for more changelog details)
Stanislav Fomichev (9):
bpf: implement getsockopt and setsockopt hooks
bpf: sync bpf.h to tools/
libbpf: support sockopt hooks
selftests/bpf: test sockopt section name
selftests/bpf: add sockopt test
selftests/bpf: add sockopt test that exercises sk helpers
selftests/bpf: add sockopt test that exercises BPF_F_ALLOW_MULTI
bpf: add sockopt documentation
bpftool: support cgroup sockopt
Documentation/bpf/index.rst | 1 +
Documentation/bpf/prog_cgroup_sockopt.rst | 93 ++
include/linux/bpf-cgroup.h | 45 +
include/linux/bpf.h | 2 +
include/linux/bpf_types.h | 1 +
include/linux/filter.h | 10 +
include/uapi/linux/bpf.h | 14 +
kernel/bpf/cgroup.c | 333 ++++++
kernel/bpf/core.c | 9 +
kernel/bpf/syscall.c | 19 +
kernel/bpf/verifier.c | 8 +
net/core/filter.c | 2 +-
net/socket.c | 30 +
.../bpftool/Documentation/bpftool-cgroup.rst | 7 +-
.../bpftool/Documentation/bpftool-prog.rst | 3 +-
tools/bpf/bpftool/bash-completion/bpftool | 9 +-
tools/bpf/bpftool/cgroup.c | 5 +-
tools/bpf/bpftool/main.h | 1 +
tools/bpf/bpftool/prog.c | 3 +-
tools/include/uapi/linux/bpf.h | 14 +
tools/lib/bpf/libbpf.c | 5 +
tools/lib/bpf/libbpf_probes.c | 1 +
tools/testing/selftests/bpf/.gitignore | 3 +
tools/testing/selftests/bpf/Makefile | 6 +-
.../selftests/bpf/progs/sockopt_multi.c | 71 ++
.../testing/selftests/bpf/progs/sockopt_sk.c | 111 ++
.../selftests/bpf/test_section_names.c | 10 +
tools/testing/selftests/bpf/test_sockopt.c | 1021 +++++++++++++++++
.../selftests/bpf/test_sockopt_multi.c | 374 ++++++
tools/testing/selftests/bpf/test_sockopt_sk.c | 214 ++++
30 files changed, 2415 insertions(+), 10 deletions(-)
create mode 100644 Documentation/bpf/prog_cgroup_sockopt.rst
create mode 100644 tools/testing/selftests/bpf/progs/sockopt_multi.c
create mode 100644 tools/testing/selftests/bpf/progs/sockopt_sk.c
create mode 100644 tools/testing/selftests/bpf/test_sockopt.c
create mode 100644 tools/testing/selftests/bpf/test_sockopt_multi.c
create mode 100644 tools/testing/selftests/bpf/test_sockopt_sk.c
--
2.22.0.410.gd8fdbe21b5-goog
^ permalink raw reply [flat|nested] 13+ messages in thread
* [PATCH bpf-next v9 1/9] bpf: implement getsockopt and setsockopt hooks
2019-06-27 20:38 [PATCH bpf-next v9 0/9] bpf: getsockopt and setsockopt hooks Stanislav Fomichev
@ 2019-06-27 20:38 ` Stanislav Fomichev
2019-06-27 20:38 ` [PATCH bpf-next v9 2/9] bpf: sync bpf.h to tools/ Stanislav Fomichev
` (8 subsequent siblings)
9 siblings, 0 replies; 13+ messages in thread
From: Stanislav Fomichev @ 2019-06-27 20:38 UTC (permalink / raw)
To: netdev, bpf
Cc: davem, ast, daniel, Stanislav Fomichev, Andrii Nakryiko, Martin Lau
Implement new BPF_PROG_TYPE_CGROUP_SOCKOPT program type and
BPF_CGROUP_{G,S}ETSOCKOPT cgroup hooks.
BPF_CGROUP_SETSOCKOPT can modify user setsockopt arguments before
passing them down to the kernel or bypass kernel completely.
BPF_CGROUP_GETSOCKOPT can can inspect/modify getsockopt arguments that
kernel returns.
Both hooks reuse existing PTR_TO_PACKET{,_END} infrastructure.
The buffer memory is pre-allocated (because I don't think there is
a precedent for working with __user memory from bpf). This might be
slow to do for each {s,g}etsockopt call, that's why I've added
__cgroup_bpf_prog_array_is_empty that exits early if there is nothing
attached to a cgroup. Note, however, that there is a race between
__cgroup_bpf_prog_array_is_empty and BPF_PROG_RUN_ARRAY where cgroup
program layout might have changed; this should not be a problem
because in general there is a race between multiple calls to
{s,g}etsocktop and user adding/removing bpf progs from a cgroup.
The return code of the BPF program is handled as follows:
* 0: EPERM
* 1: success, continue with next BPF program in the cgroup chain
v9:
* allow overwriting setsockopt arguments (Alexei Starovoitov):
* use set_fs (same as kernel_setsockopt)
* buffer is always kzalloc'd (no small on-stack buffer)
v8:
* use s32 for optlen (Andrii Nakryiko)
v7:
* return only 0 or 1 (Alexei Starovoitov)
* always run all progs (Alexei Starovoitov)
* use optval=0 as kernel bypass in setsockopt (Alexei Starovoitov)
(decided to use optval=-1 instead, optval=0 might be a valid input)
* call getsockopt hook after kernel handlers (Alexei Starovoitov)
v6:
* rework cgroup chaining; stop as soon as bpf program returns
0 or 2; see patch with the documentation for the details
* drop Andrii's and Martin's Acked-by (not sure they are comfortable
with the new state of things)
v5:
* skip copy_to_user() and put_user() when ret == 0 (Martin Lau)
v4:
* don't export bpf_sk_fullsock helper (Martin Lau)
* size != sizeof(__u64) for uapi pointers (Martin Lau)
* offsetof instead of bpf_ctx_range when checking ctx access (Martin Lau)
v3:
* typos in BPF_PROG_CGROUP_SOCKOPT_RUN_ARRAY comments (Andrii Nakryiko)
* reverse christmas tree in BPF_PROG_CGROUP_SOCKOPT_RUN_ARRAY (Andrii
Nakryiko)
* use __bpf_md_ptr instead of __u32 for optval{,_end} (Martin Lau)
* use BPF_FIELD_SIZEOF() for consistency (Martin Lau)
* new CG_SOCKOPT_ACCESS macro to wrap repeated parts
v2:
* moved bpf_sockopt_kern fields around to remove a hole (Martin Lau)
* aligned bpf_sockopt_kern->buf to 8 bytes (Martin Lau)
* bpf_prog_array_is_empty instead of bpf_prog_array_length (Martin Lau)
* added [0,2] return code check to verifier (Martin Lau)
* dropped unused buf[64] from the stack (Martin Lau)
* use PTR_TO_SOCKET for bpf_sockopt->sk (Martin Lau)
* dropped bpf_target_off from ctx rewrites (Martin Lau)
* use return code for kernel bypass (Martin Lau & Andrii Nakryiko)
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Martin Lau <kafai@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
---
include/linux/bpf-cgroup.h | 45 +++++
include/linux/bpf.h | 2 +
include/linux/bpf_types.h | 1 +
include/linux/filter.h | 10 ++
include/uapi/linux/bpf.h | 14 ++
kernel/bpf/cgroup.c | 333 +++++++++++++++++++++++++++++++++++++
kernel/bpf/core.c | 9 +
kernel/bpf/syscall.c | 19 +++
kernel/bpf/verifier.c | 8 +
net/core/filter.c | 2 +-
net/socket.c | 30 ++++
11 files changed, 472 insertions(+), 1 deletion(-)
diff --git a/include/linux/bpf-cgroup.h b/include/linux/bpf-cgroup.h
index bd79ae32909a..169fd25f6bc2 100644
--- a/include/linux/bpf-cgroup.h
+++ b/include/linux/bpf-cgroup.h
@@ -124,6 +124,14 @@ int __cgroup_bpf_run_filter_sysctl(struct ctl_table_header *head,
loff_t *ppos, void **new_buf,
enum bpf_attach_type type);
+int __cgroup_bpf_run_filter_setsockopt(struct sock *sock, int *level,
+ int *optname, char __user *optval,
+ int *optlen, char **kernel_optval);
+int __cgroup_bpf_run_filter_getsockopt(struct sock *sk, int level,
+ int optname, char __user *optval,
+ int __user *optlen, int max_optlen,
+ int retval);
+
static inline enum bpf_cgroup_storage_type cgroup_storage_type(
struct bpf_map *map)
{
@@ -286,6 +294,38 @@ int bpf_percpu_cgroup_storage_update(struct bpf_map *map, void *key,
__ret; \
})
+#define BPF_CGROUP_RUN_PROG_SETSOCKOPT(sock, level, optname, optval, optlen, \
+ kernel_optval) \
+({ \
+ int __ret = 0; \
+ if (cgroup_bpf_enabled) \
+ __ret = __cgroup_bpf_run_filter_setsockopt(sock, level, \
+ optname, optval, \
+ optlen, \
+ kernel_optval); \
+ __ret; \
+})
+
+#define BPF_CGROUP_GETSOCKOPT_MAX_OPTLEN(optlen) \
+({ \
+ int __ret = 0; \
+ if (cgroup_bpf_enabled) \
+ get_user(__ret, optlen); \
+ __ret; \
+})
+
+#define BPF_CGROUP_RUN_PROG_GETSOCKOPT(sock, level, optname, optval, optlen, \
+ max_optlen, retval) \
+({ \
+ int __ret = retval; \
+ if (cgroup_bpf_enabled) \
+ __ret = __cgroup_bpf_run_filter_getsockopt(sock, level, \
+ optname, optval, \
+ optlen, max_optlen, \
+ retval); \
+ __ret; \
+})
+
int cgroup_bpf_prog_attach(const union bpf_attr *attr,
enum bpf_prog_type ptype, struct bpf_prog *prog);
int cgroup_bpf_prog_detach(const union bpf_attr *attr,
@@ -357,6 +397,11 @@ static inline int bpf_percpu_cgroup_storage_update(struct bpf_map *map,
#define BPF_CGROUP_RUN_PROG_SOCK_OPS(sock_ops) ({ 0; })
#define BPF_CGROUP_RUN_PROG_DEVICE_CGROUP(type,major,minor,access) ({ 0; })
#define BPF_CGROUP_RUN_PROG_SYSCTL(head,table,write,buf,count,pos,nbuf) ({ 0; })
+#define BPF_CGROUP_GETSOCKOPT_MAX_OPTLEN(optlen) ({ 0; })
+#define BPF_CGROUP_RUN_PROG_GETSOCKOPT(sock, level, optname, optval, \
+ optlen, max_optlen, retval) ({ retval; })
+#define BPF_CGROUP_RUN_PROG_SETSOCKOPT(sock, level, optname, optval, optlen, \
+ kernel_optval) ({ 0; })
#define for_each_cgroup_storage_type(stype) for (; false; )
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index a62e7889b0b6..18f4cc2c6acd 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -518,6 +518,7 @@ struct bpf_prog_array {
struct bpf_prog_array *bpf_prog_array_alloc(u32 prog_cnt, gfp_t flags);
void bpf_prog_array_free(struct bpf_prog_array *progs);
int bpf_prog_array_length(struct bpf_prog_array *progs);
+bool bpf_prog_array_is_empty(struct bpf_prog_array *array);
int bpf_prog_array_copy_to_user(struct bpf_prog_array *progs,
__u32 __user *prog_ids, u32 cnt);
@@ -1051,6 +1052,7 @@ extern const struct bpf_func_proto bpf_spin_unlock_proto;
extern const struct bpf_func_proto bpf_get_local_storage_proto;
extern const struct bpf_func_proto bpf_strtol_proto;
extern const struct bpf_func_proto bpf_strtoul_proto;
+extern const struct bpf_func_proto bpf_tcp_sock_proto;
/* Shared helpers among cBPF and eBPF. */
void bpf_user_rnd_init_once(void);
diff --git a/include/linux/bpf_types.h b/include/linux/bpf_types.h
index 5a9975678d6f..eec5aeeeaf92 100644
--- a/include/linux/bpf_types.h
+++ b/include/linux/bpf_types.h
@@ -30,6 +30,7 @@ BPF_PROG_TYPE(BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE, raw_tracepoint_writable)
#ifdef CONFIG_CGROUP_BPF
BPF_PROG_TYPE(BPF_PROG_TYPE_CGROUP_DEVICE, cg_dev)
BPF_PROG_TYPE(BPF_PROG_TYPE_CGROUP_SYSCTL, cg_sysctl)
+BPF_PROG_TYPE(BPF_PROG_TYPE_CGROUP_SOCKOPT, cg_sockopt)
#endif
#ifdef CONFIG_BPF_LIRC_MODE2
BPF_PROG_TYPE(BPF_PROG_TYPE_LIRC_MODE2, lirc_mode2)
diff --git a/include/linux/filter.h b/include/linux/filter.h
index 43b45d6db36d..340f7d648974 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -1199,4 +1199,14 @@ struct bpf_sysctl_kern {
u64 tmp_reg;
};
+struct bpf_sockopt_kern {
+ struct sock *sk;
+ u8 *optval;
+ u8 *optval_end;
+ s32 level;
+ s32 optname;
+ s32 optlen;
+ s32 retval;
+};
+
#endif /* __LINUX_FILTER_H__ */
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index b077507efa3f..a396b516a2b2 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -170,6 +170,7 @@ enum bpf_prog_type {
BPF_PROG_TYPE_FLOW_DISSECTOR,
BPF_PROG_TYPE_CGROUP_SYSCTL,
BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE,
+ BPF_PROG_TYPE_CGROUP_SOCKOPT,
};
enum bpf_attach_type {
@@ -194,6 +195,8 @@ enum bpf_attach_type {
BPF_CGROUP_SYSCTL,
BPF_CGROUP_UDP4_RECVMSG,
BPF_CGROUP_UDP6_RECVMSG,
+ BPF_CGROUP_GETSOCKOPT,
+ BPF_CGROUP_SETSOCKOPT,
__MAX_BPF_ATTACH_TYPE
};
@@ -3541,4 +3544,15 @@ struct bpf_sysctl {
*/
};
+struct bpf_sockopt {
+ __bpf_md_ptr(struct bpf_sock *, sk);
+ __bpf_md_ptr(void *, optval);
+ __bpf_md_ptr(void *, optval_end);
+
+ __s32 level;
+ __s32 optname;
+ __s32 optlen;
+ __s32 retval;
+};
+
#endif /* _UAPI__LINUX_BPF_H__ */
diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c
index 077ed3a19848..76fa0076f20d 100644
--- a/kernel/bpf/cgroup.c
+++ b/kernel/bpf/cgroup.c
@@ -15,6 +15,7 @@
#include <linux/bpf.h>
#include <linux/bpf-cgroup.h>
#include <net/sock.h>
+#include <net/bpf_sk_storage.h>
#include "../cgroup/cgroup-internal.h"
@@ -938,6 +939,188 @@ int __cgroup_bpf_run_filter_sysctl(struct ctl_table_header *head,
}
EXPORT_SYMBOL(__cgroup_bpf_run_filter_sysctl);
+static bool __cgroup_bpf_prog_array_is_empty(struct cgroup *cgrp,
+ enum bpf_attach_type attach_type)
+{
+ struct bpf_prog_array *prog_array;
+ bool empty;
+
+ rcu_read_lock();
+ prog_array = rcu_dereference(cgrp->bpf.effective[attach_type]);
+ empty = bpf_prog_array_is_empty(prog_array);
+ rcu_read_unlock();
+
+ return empty;
+}
+
+static int sockopt_alloc_buf(struct bpf_sockopt_kern *ctx, int max_optlen)
+{
+ if (unlikely(max_optlen > PAGE_SIZE) || max_optlen < 0)
+ return -EINVAL;
+
+ ctx->optval = kzalloc(max_optlen, GFP_USER);
+ if (!ctx->optval)
+ return -ENOMEM;
+
+ ctx->optval_end = ctx->optval + max_optlen;
+ ctx->optlen = max_optlen;
+
+ return 0;
+}
+
+static void sockopt_free_buf(struct bpf_sockopt_kern *ctx)
+{
+ kfree(ctx->optval);
+}
+
+int __cgroup_bpf_run_filter_setsockopt(struct sock *sk, int *level,
+ int *optname, char __user *optval,
+ int *optlen, char **kernel_optval)
+{
+ struct cgroup *cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
+ struct bpf_sockopt_kern ctx = {
+ .sk = sk,
+ .level = *level,
+ .optname = *optname,
+ };
+ int ret;
+
+ /* Opportunistic check to see whether we have any BPF program
+ * attached to the hook so we don't waste time allocating
+ * memory and locking the socket.
+ */
+ if (!cgroup_bpf_enabled ||
+ __cgroup_bpf_prog_array_is_empty(cgrp, BPF_CGROUP_SETSOCKOPT))
+ return 0;
+
+ ret = sockopt_alloc_buf(&ctx, *optlen);
+ if (ret)
+ return ret;
+
+ if (copy_from_user(ctx.optval, optval, *optlen) != 0) {
+ ret = -EFAULT;
+ goto out;
+ }
+
+ lock_sock(sk);
+ ret = BPF_PROG_RUN_ARRAY(cgrp->bpf.effective[BPF_CGROUP_SETSOCKOPT],
+ &ctx, BPF_PROG_RUN);
+ release_sock(sk);
+
+ if (!ret) {
+ ret = -EPERM;
+ goto out;
+ }
+
+ if (ctx.optlen == -1) {
+ /* optlen set to -1, bypass kernel */
+ ret = 1;
+ } else if (ctx.optlen > *optlen || ctx.optlen < -1) {
+ /* optlen is out of bounds */
+ ret = -EFAULT;
+ } else {
+ /* optlen within bounds, run kernel handler */
+ ret = 0;
+
+ /* export any potential modifications */
+ *level = ctx.level;
+ *optname = ctx.optname;
+ *optlen = ctx.optlen;
+ *kernel_optval = ctx.optval;
+ }
+
+out:
+ if (ret)
+ sockopt_free_buf(&ctx);
+ return ret;
+}
+EXPORT_SYMBOL(__cgroup_bpf_run_filter_setsockopt);
+
+int __cgroup_bpf_run_filter_getsockopt(struct sock *sk, int level,
+ int optname, char __user *optval,
+ int __user *optlen, int max_optlen,
+ int retval)
+{
+ struct cgroup *cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
+ struct bpf_sockopt_kern ctx = {
+ .sk = sk,
+ .level = level,
+ .optname = optname,
+ .retval = retval,
+ };
+ int ret;
+
+ /* Opportunistic check to see whether we have any BPF program
+ * attached to the hook so we don't waste time allocating
+ * memory and locking the socket.
+ */
+ if (!cgroup_bpf_enabled ||
+ __cgroup_bpf_prog_array_is_empty(cgrp, BPF_CGROUP_GETSOCKOPT))
+ return retval;
+
+ ret = sockopt_alloc_buf(&ctx, max_optlen);
+ if (ret)
+ return ret;
+
+ if (!retval) {
+ /* If kernel getsockopt finished successfully,
+ * copy whatever was returned to the user back
+ * into our temporary buffer. Set optlen to the
+ * one that kernel returned as well to let
+ * BPF programs inspect the value.
+ */
+
+ if (get_user(ctx.optlen, optlen)) {
+ ret = -EFAULT;
+ goto out;
+ }
+
+ if (ctx.optlen > max_optlen)
+ ctx.optlen = max_optlen;
+
+ if (copy_from_user(ctx.optval, optval, ctx.optlen) != 0) {
+ ret = -EFAULT;
+ goto out;
+ }
+ }
+
+ lock_sock(sk);
+ ret = BPF_PROG_RUN_ARRAY(cgrp->bpf.effective[BPF_CGROUP_GETSOCKOPT],
+ &ctx, BPF_PROG_RUN);
+ release_sock(sk);
+
+ if (!ret) {
+ ret = -EPERM;
+ goto out;
+ }
+
+ if (ctx.optlen > max_optlen) {
+ ret = -EFAULT;
+ goto out;
+ }
+
+ /* BPF programs only allowed to set retval to 0, not some
+ * arbitrary value.
+ */
+ if (ctx.retval != 0 && ctx.retval != retval) {
+ ret = -EFAULT;
+ goto out;
+ }
+
+ if (copy_to_user(optval, ctx.optval, ctx.optlen) ||
+ put_user(ctx.optlen, optlen)) {
+ ret = -EFAULT;
+ goto out;
+ }
+
+ ret = ctx.retval;
+
+out:
+ sockopt_free_buf(&ctx);
+ return ret;
+}
+EXPORT_SYMBOL(__cgroup_bpf_run_filter_getsockopt);
+
static ssize_t sysctl_cpy_dir(const struct ctl_dir *dir, char **bufp,
size_t *lenp)
{
@@ -1198,3 +1381,153 @@ const struct bpf_verifier_ops cg_sysctl_verifier_ops = {
const struct bpf_prog_ops cg_sysctl_prog_ops = {
};
+
+static const struct bpf_func_proto *
+cg_sockopt_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
+{
+ switch (func_id) {
+ case BPF_FUNC_sk_storage_get:
+ return &bpf_sk_storage_get_proto;
+ case BPF_FUNC_sk_storage_delete:
+ return &bpf_sk_storage_delete_proto;
+#ifdef CONFIG_INET
+ case BPF_FUNC_tcp_sock:
+ return &bpf_tcp_sock_proto;
+#endif
+ default:
+ return cgroup_base_func_proto(func_id, prog);
+ }
+}
+
+static bool cg_sockopt_is_valid_access(int off, int size,
+ enum bpf_access_type type,
+ const struct bpf_prog *prog,
+ struct bpf_insn_access_aux *info)
+{
+ const int size_default = sizeof(__u32);
+
+ if (off < 0 || off >= sizeof(struct bpf_sockopt))
+ return false;
+
+ if (off % size != 0)
+ return false;
+
+ if (type == BPF_WRITE) {
+ switch (off) {
+ case offsetof(struct bpf_sockopt, retval):
+ if (size != size_default)
+ return false;
+ return prog->expected_attach_type ==
+ BPF_CGROUP_GETSOCKOPT;
+ case offsetof(struct bpf_sockopt, optname):
+ /* fallthrough */
+ case offsetof(struct bpf_sockopt, level):
+ if (size != size_default)
+ return false;
+ return prog->expected_attach_type ==
+ BPF_CGROUP_SETSOCKOPT;
+ case offsetof(struct bpf_sockopt, optlen):
+ return size == size_default;
+ default:
+ return false;
+ }
+ }
+
+ switch (off) {
+ case offsetof(struct bpf_sockopt, sk):
+ if (size != sizeof(__u64))
+ return false;
+ info->reg_type = PTR_TO_SOCKET;
+ break;
+ case offsetof(struct bpf_sockopt, optval):
+ if (size != sizeof(__u64))
+ return false;
+ info->reg_type = PTR_TO_PACKET;
+ break;
+ case offsetof(struct bpf_sockopt, optval_end):
+ if (size != sizeof(__u64))
+ return false;
+ info->reg_type = PTR_TO_PACKET_END;
+ break;
+ case offsetof(struct bpf_sockopt, retval):
+ if (size != size_default)
+ return false;
+ return prog->expected_attach_type == BPF_CGROUP_GETSOCKOPT;
+ default:
+ if (size != size_default)
+ return false;
+ break;
+ }
+ return true;
+}
+
+#define CG_SOCKOPT_ACCESS_FIELD(T, F) \
+ T(BPF_FIELD_SIZEOF(struct bpf_sockopt_kern, F), \
+ si->dst_reg, si->src_reg, \
+ offsetof(struct bpf_sockopt_kern, F))
+
+static u32 cg_sockopt_convert_ctx_access(enum bpf_access_type type,
+ const struct bpf_insn *si,
+ struct bpf_insn *insn_buf,
+ struct bpf_prog *prog,
+ u32 *target_size)
+{
+ struct bpf_insn *insn = insn_buf;
+
+ switch (si->off) {
+ case offsetof(struct bpf_sockopt, sk):
+ *insn++ = CG_SOCKOPT_ACCESS_FIELD(BPF_LDX_MEM, sk);
+ break;
+ case offsetof(struct bpf_sockopt, level):
+ if (type == BPF_WRITE)
+ *insn++ = CG_SOCKOPT_ACCESS_FIELD(BPF_STX_MEM, level);
+ else
+ *insn++ = CG_SOCKOPT_ACCESS_FIELD(BPF_LDX_MEM, level);
+ break;
+ case offsetof(struct bpf_sockopt, optname):
+ if (type == BPF_WRITE)
+ *insn++ = CG_SOCKOPT_ACCESS_FIELD(BPF_STX_MEM, optname);
+ else
+ *insn++ = CG_SOCKOPT_ACCESS_FIELD(BPF_LDX_MEM, optname);
+ break;
+ case offsetof(struct bpf_sockopt, optlen):
+ if (type == BPF_WRITE)
+ *insn++ = CG_SOCKOPT_ACCESS_FIELD(BPF_STX_MEM, optlen);
+ else
+ *insn++ = CG_SOCKOPT_ACCESS_FIELD(BPF_LDX_MEM, optlen);
+ break;
+ case offsetof(struct bpf_sockopt, retval):
+ if (type == BPF_WRITE)
+ *insn++ = CG_SOCKOPT_ACCESS_FIELD(BPF_STX_MEM, retval);
+ else
+ *insn++ = CG_SOCKOPT_ACCESS_FIELD(BPF_LDX_MEM, retval);
+ break;
+ case offsetof(struct bpf_sockopt, optval):
+ *insn++ = CG_SOCKOPT_ACCESS_FIELD(BPF_LDX_MEM, optval);
+ break;
+ case offsetof(struct bpf_sockopt, optval_end):
+ *insn++ = CG_SOCKOPT_ACCESS_FIELD(BPF_LDX_MEM, optval_end);
+ break;
+ }
+
+ return insn - insn_buf;
+}
+
+static int cg_sockopt_get_prologue(struct bpf_insn *insn_buf,
+ bool direct_write,
+ const struct bpf_prog *prog)
+{
+ /* Nothing to do for sockopt argument. The data is kzalloc'ated.
+ */
+ return 0;
+}
+
+const struct bpf_verifier_ops cg_sockopt_verifier_ops = {
+ .get_func_proto = cg_sockopt_func_proto,
+ .is_valid_access = cg_sockopt_is_valid_access,
+ .convert_ctx_access = cg_sockopt_convert_ctx_access,
+ .gen_prologue = cg_sockopt_get_prologue,
+};
+
+const struct bpf_prog_ops cg_sockopt_prog_ops = {
+};
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 561ed07d3007..e2c1b43728da 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -1809,6 +1809,15 @@ int bpf_prog_array_length(struct bpf_prog_array *array)
return cnt;
}
+bool bpf_prog_array_is_empty(struct bpf_prog_array *array)
+{
+ struct bpf_prog_array_item *item;
+
+ for (item = array->items; item->prog; item++)
+ if (item->prog != &dummy_bpf_prog.prog)
+ return false;
+ return true;
+}
static bool bpf_prog_array_copy_core(struct bpf_prog_array *array,
u32 *prog_ids,
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 7713cf39795a..b0f545e07425 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -1590,6 +1590,14 @@ bpf_prog_load_check_attach_type(enum bpf_prog_type prog_type,
default:
return -EINVAL;
}
+ case BPF_PROG_TYPE_CGROUP_SOCKOPT:
+ switch (expected_attach_type) {
+ case BPF_CGROUP_SETSOCKOPT:
+ case BPF_CGROUP_GETSOCKOPT:
+ return 0;
+ default:
+ return -EINVAL;
+ }
default:
return 0;
}
@@ -1840,6 +1848,7 @@ static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
switch (prog->type) {
case BPF_PROG_TYPE_CGROUP_SOCK:
case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
+ case BPF_PROG_TYPE_CGROUP_SOCKOPT:
return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
case BPF_PROG_TYPE_CGROUP_SKB:
return prog->enforce_expected_attach_type &&
@@ -1912,6 +1921,10 @@ static int bpf_prog_attach(const union bpf_attr *attr)
case BPF_CGROUP_SYSCTL:
ptype = BPF_PROG_TYPE_CGROUP_SYSCTL;
break;
+ case BPF_CGROUP_GETSOCKOPT:
+ case BPF_CGROUP_SETSOCKOPT:
+ ptype = BPF_PROG_TYPE_CGROUP_SOCKOPT;
+ break;
default:
return -EINVAL;
}
@@ -1995,6 +2008,10 @@ static int bpf_prog_detach(const union bpf_attr *attr)
case BPF_CGROUP_SYSCTL:
ptype = BPF_PROG_TYPE_CGROUP_SYSCTL;
break;
+ case BPF_CGROUP_GETSOCKOPT:
+ case BPF_CGROUP_SETSOCKOPT:
+ ptype = BPF_PROG_TYPE_CGROUP_SOCKOPT;
+ break;
default:
return -EINVAL;
}
@@ -2031,6 +2048,8 @@ static int bpf_prog_query(const union bpf_attr *attr,
case BPF_CGROUP_SOCK_OPS:
case BPF_CGROUP_DEVICE:
case BPF_CGROUP_SYSCTL:
+ case BPF_CGROUP_GETSOCKOPT:
+ case BPF_CGROUP_SETSOCKOPT:
break;
case BPF_LIRC_MODE2:
return lirc_prog_query(attr, uattr);
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 0e079b2298f8..6b5623d320f9 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -2215,6 +2215,13 @@ static bool may_access_direct_pkt_data(struct bpf_verifier_env *env,
env->seen_direct_write = true;
return true;
+
+ case BPF_PROG_TYPE_CGROUP_SOCKOPT:
+ if (t == BPF_WRITE)
+ env->seen_direct_write = true;
+
+ return true;
+
default:
return false;
}
@@ -6066,6 +6073,7 @@ static int check_return_code(struct bpf_verifier_env *env)
case BPF_PROG_TYPE_SOCK_OPS:
case BPF_PROG_TYPE_CGROUP_DEVICE:
case BPF_PROG_TYPE_CGROUP_SYSCTL:
+ case BPF_PROG_TYPE_CGROUP_SOCKOPT:
break;
default:
return 0;
diff --git a/net/core/filter.c b/net/core/filter.c
index 2014d76e0d2a..dc8534be12fc 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -5651,7 +5651,7 @@ BPF_CALL_1(bpf_tcp_sock, struct sock *, sk)
return (unsigned long)NULL;
}
-static const struct bpf_func_proto bpf_tcp_sock_proto = {
+const struct bpf_func_proto bpf_tcp_sock_proto = {
.func = bpf_tcp_sock,
.gpl_only = false,
.ret_type = RET_PTR_TO_TCP_SOCK_OR_NULL,
diff --git a/net/socket.c b/net/socket.c
index 963df5dbdd54..0ddfbfb761d9 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -2051,6 +2051,8 @@ SYSCALL_DEFINE4(recv, int, fd, void __user *, ubuf, size_t, size,
static int __sys_setsockopt(int fd, int level, int optname,
char __user *optval, int optlen)
{
+ mm_segment_t oldfs = get_fs();
+ char *kernel_optval = NULL;
int err, fput_needed;
struct socket *sock;
@@ -2063,6 +2065,22 @@ static int __sys_setsockopt(int fd, int level, int optname,
if (err)
goto out_put;
+ err = BPF_CGROUP_RUN_PROG_SETSOCKOPT(sock->sk, &level,
+ &optname, optval, &optlen,
+ &kernel_optval);
+
+ if (err < 0) {
+ goto out_put;
+ } else if (err > 0) {
+ err = 0;
+ goto out_put;
+ }
+
+ if (kernel_optval) {
+ set_fs(KERNEL_DS);
+ optval = (char __user __force *)kernel_optval;
+ }
+
if (level == SOL_SOCKET)
err =
sock_setsockopt(sock, level, optname, optval,
@@ -2071,6 +2089,11 @@ static int __sys_setsockopt(int fd, int level, int optname,
err =
sock->ops->setsockopt(sock, level, optname, optval,
optlen);
+
+ if (kernel_optval) {
+ set_fs(oldfs);
+ kfree(kernel_optval);
+ }
out_put:
fput_light(sock->file, fput_needed);
}
@@ -2093,6 +2116,7 @@ static int __sys_getsockopt(int fd, int level, int optname,
{
int err, fput_needed;
struct socket *sock;
+ int max_optlen;
sock = sockfd_lookup_light(fd, &err, &fput_needed);
if (sock != NULL) {
@@ -2100,6 +2124,8 @@ static int __sys_getsockopt(int fd, int level, int optname,
if (err)
goto out_put;
+ max_optlen = BPF_CGROUP_GETSOCKOPT_MAX_OPTLEN(optlen);
+
if (level == SOL_SOCKET)
err =
sock_getsockopt(sock, level, optname, optval,
@@ -2108,6 +2134,10 @@ static int __sys_getsockopt(int fd, int level, int optname,
err =
sock->ops->getsockopt(sock, level, optname, optval,
optlen);
+
+ err = BPF_CGROUP_RUN_PROG_GETSOCKOPT(sock->sk, level, optname,
+ optval, optlen,
+ max_optlen, err);
out_put:
fput_light(sock->file, fput_needed);
}
--
2.22.0.410.gd8fdbe21b5-goog
^ permalink raw reply related [flat|nested] 13+ messages in thread
* [PATCH bpf-next v9 2/9] bpf: sync bpf.h to tools/
2019-06-27 20:38 [PATCH bpf-next v9 0/9] bpf: getsockopt and setsockopt hooks Stanislav Fomichev
2019-06-27 20:38 ` [PATCH bpf-next v9 1/9] bpf: implement " Stanislav Fomichev
@ 2019-06-27 20:38 ` Stanislav Fomichev
2019-06-27 20:38 ` [PATCH bpf-next v9 3/9] libbpf: support sockopt hooks Stanislav Fomichev
` (7 subsequent siblings)
9 siblings, 0 replies; 13+ messages in thread
From: Stanislav Fomichev @ 2019-06-27 20:38 UTC (permalink / raw)
To: netdev, bpf
Cc: davem, ast, daniel, Stanislav Fomichev, Andrii Nakryiko, Martin Lau
Export new prog type and hook points to the libbpf.
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Martin Lau <kafai@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
---
tools/include/uapi/linux/bpf.h | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index b077507efa3f..a396b516a2b2 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -170,6 +170,7 @@ enum bpf_prog_type {
BPF_PROG_TYPE_FLOW_DISSECTOR,
BPF_PROG_TYPE_CGROUP_SYSCTL,
BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE,
+ BPF_PROG_TYPE_CGROUP_SOCKOPT,
};
enum bpf_attach_type {
@@ -194,6 +195,8 @@ enum bpf_attach_type {
BPF_CGROUP_SYSCTL,
BPF_CGROUP_UDP4_RECVMSG,
BPF_CGROUP_UDP6_RECVMSG,
+ BPF_CGROUP_GETSOCKOPT,
+ BPF_CGROUP_SETSOCKOPT,
__MAX_BPF_ATTACH_TYPE
};
@@ -3541,4 +3544,15 @@ struct bpf_sysctl {
*/
};
+struct bpf_sockopt {
+ __bpf_md_ptr(struct bpf_sock *, sk);
+ __bpf_md_ptr(void *, optval);
+ __bpf_md_ptr(void *, optval_end);
+
+ __s32 level;
+ __s32 optname;
+ __s32 optlen;
+ __s32 retval;
+};
+
#endif /* _UAPI__LINUX_BPF_H__ */
--
2.22.0.410.gd8fdbe21b5-goog
^ permalink raw reply related [flat|nested] 13+ messages in thread
* [PATCH bpf-next v9 3/9] libbpf: support sockopt hooks
2019-06-27 20:38 [PATCH bpf-next v9 0/9] bpf: getsockopt and setsockopt hooks Stanislav Fomichev
2019-06-27 20:38 ` [PATCH bpf-next v9 1/9] bpf: implement " Stanislav Fomichev
2019-06-27 20:38 ` [PATCH bpf-next v9 2/9] bpf: sync bpf.h to tools/ Stanislav Fomichev
@ 2019-06-27 20:38 ` Stanislav Fomichev
2019-06-27 20:38 ` [PATCH bpf-next v9 4/9] selftests/bpf: test sockopt section name Stanislav Fomichev
` (6 subsequent siblings)
9 siblings, 0 replies; 13+ messages in thread
From: Stanislav Fomichev @ 2019-06-27 20:38 UTC (permalink / raw)
To: netdev, bpf
Cc: davem, ast, daniel, Stanislav Fomichev, Andrii Nakryiko, Martin Lau
Make libbpf aware of new sockopt hooks so it can derive prog type
and hook point from the section names.
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Martin Lau <kafai@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
---
tools/lib/bpf/libbpf.c | 5 +++++
tools/lib/bpf/libbpf_probes.c | 1 +
2 files changed, 6 insertions(+)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 5186b7710430..6e6ebef11ba3 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -2646,6 +2646,7 @@ static bool bpf_prog_type__needs_kver(enum bpf_prog_type type)
case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
case BPF_PROG_TYPE_PERF_EVENT:
case BPF_PROG_TYPE_CGROUP_SYSCTL:
+ case BPF_PROG_TYPE_CGROUP_SOCKOPT:
return false;
case BPF_PROG_TYPE_KPROBE:
default:
@@ -3604,6 +3605,10 @@ static const struct {
BPF_CGROUP_UDP6_RECVMSG),
BPF_EAPROG_SEC("cgroup/sysctl", BPF_PROG_TYPE_CGROUP_SYSCTL,
BPF_CGROUP_SYSCTL),
+ BPF_EAPROG_SEC("cgroup/getsockopt", BPF_PROG_TYPE_CGROUP_SOCKOPT,
+ BPF_CGROUP_GETSOCKOPT),
+ BPF_EAPROG_SEC("cgroup/setsockopt", BPF_PROG_TYPE_CGROUP_SOCKOPT,
+ BPF_CGROUP_SETSOCKOPT),
};
#undef BPF_PROG_SEC_IMPL
diff --git a/tools/lib/bpf/libbpf_probes.c b/tools/lib/bpf/libbpf_probes.c
index 6635a31a7a16..ace1a0708d99 100644
--- a/tools/lib/bpf/libbpf_probes.c
+++ b/tools/lib/bpf/libbpf_probes.c
@@ -101,6 +101,7 @@ probe_load(enum bpf_prog_type prog_type, const struct bpf_insn *insns,
case BPF_PROG_TYPE_SK_REUSEPORT:
case BPF_PROG_TYPE_FLOW_DISSECTOR:
case BPF_PROG_TYPE_CGROUP_SYSCTL:
+ case BPF_PROG_TYPE_CGROUP_SOCKOPT:
default:
break;
}
--
2.22.0.410.gd8fdbe21b5-goog
^ permalink raw reply related [flat|nested] 13+ messages in thread
* [PATCH bpf-next v9 4/9] selftests/bpf: test sockopt section name
2019-06-27 20:38 [PATCH bpf-next v9 0/9] bpf: getsockopt and setsockopt hooks Stanislav Fomichev
` (2 preceding siblings ...)
2019-06-27 20:38 ` [PATCH bpf-next v9 3/9] libbpf: support sockopt hooks Stanislav Fomichev
@ 2019-06-27 20:38 ` Stanislav Fomichev
2019-06-27 20:38 ` [PATCH bpf-next v9 5/9] selftests/bpf: add sockopt test Stanislav Fomichev
` (5 subsequent siblings)
9 siblings, 0 replies; 13+ messages in thread
From: Stanislav Fomichev @ 2019-06-27 20:38 UTC (permalink / raw)
To: netdev, bpf
Cc: davem, ast, daniel, Stanislav Fomichev, Andrii Nakryiko, Martin Lau
Add tests that make sure libbpf section detection works.
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Martin Lau <kafai@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
---
tools/testing/selftests/bpf/test_section_names.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/tools/testing/selftests/bpf/test_section_names.c b/tools/testing/selftests/bpf/test_section_names.c
index dee2f2eceb0f..29833aeaf0de 100644
--- a/tools/testing/selftests/bpf/test_section_names.c
+++ b/tools/testing/selftests/bpf/test_section_names.c
@@ -134,6 +134,16 @@ static struct sec_name_test tests[] = {
{0, BPF_PROG_TYPE_CGROUP_SYSCTL, BPF_CGROUP_SYSCTL},
{0, BPF_CGROUP_SYSCTL},
},
+ {
+ "cgroup/getsockopt",
+ {0, BPF_PROG_TYPE_CGROUP_SOCKOPT, BPF_CGROUP_GETSOCKOPT},
+ {0, BPF_CGROUP_GETSOCKOPT},
+ },
+ {
+ "cgroup/setsockopt",
+ {0, BPF_PROG_TYPE_CGROUP_SOCKOPT, BPF_CGROUP_SETSOCKOPT},
+ {0, BPF_CGROUP_SETSOCKOPT},
+ },
};
static int test_prog_type_by_name(const struct sec_name_test *test)
--
2.22.0.410.gd8fdbe21b5-goog
^ permalink raw reply related [flat|nested] 13+ messages in thread
* [PATCH bpf-next v9 5/9] selftests/bpf: add sockopt test
2019-06-27 20:38 [PATCH bpf-next v9 0/9] bpf: getsockopt and setsockopt hooks Stanislav Fomichev
` (3 preceding siblings ...)
2019-06-27 20:38 ` [PATCH bpf-next v9 4/9] selftests/bpf: test sockopt section name Stanislav Fomichev
@ 2019-06-27 20:38 ` Stanislav Fomichev
2019-06-27 20:38 ` [PATCH bpf-next v9 6/9] selftests/bpf: add sockopt test that exercises sk helpers Stanislav Fomichev
` (4 subsequent siblings)
9 siblings, 0 replies; 13+ messages in thread
From: Stanislav Fomichev @ 2019-06-27 20:38 UTC (permalink / raw)
To: netdev, bpf
Cc: davem, ast, daniel, Stanislav Fomichev, Andrii Nakryiko, Martin Lau
Add sockopt selftests:
* require proper expected_attach_type
* enforce context field read/write access
* test bpf_sockopt_handled handler
* test EPERM
* test limiting optlen from getsockopt
* test out-of-bounds access
v9:
* add tests for setsockopt argument mangling
v7:
* remove return 2; test retval=0 and optlen=-1
v3:
* use DW for optval{,_end} loads
v2:
* use return code 2 for kernel bypass
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Martin Lau <kafai@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
---
tools/testing/selftests/bpf/.gitignore | 1 +
tools/testing/selftests/bpf/Makefile | 3 +-
tools/testing/selftests/bpf/test_sockopt.c | 1021 ++++++++++++++++++++
3 files changed, 1024 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/bpf/test_sockopt.c
diff --git a/tools/testing/selftests/bpf/.gitignore b/tools/testing/selftests/bpf/.gitignore
index 7470327edcfe..3fe92601223d 100644
--- a/tools/testing/selftests/bpf/.gitignore
+++ b/tools/testing/selftests/bpf/.gitignore
@@ -39,3 +39,4 @@ libbpf.so.*
test_hashmap
test_btf_dump
xdping
+test_sockopt
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index faeb8220daa2..7f2210402e57 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -26,7 +26,7 @@ TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test
test_sock test_btf test_sockmap get_cgroup_id_user test_socket_cookie \
test_cgroup_storage test_select_reuseport test_section_names \
test_netcnt test_tcpnotify_user test_sock_fields test_sysctl test_hashmap \
- test_btf_dump test_cgroup_attach xdping
+ test_btf_dump test_cgroup_attach xdping test_sockopt
BPF_OBJ_FILES = $(patsubst %.c,%.o, $(notdir $(wildcard progs/*.c)))
TEST_GEN_FILES = $(BPF_OBJ_FILES)
@@ -103,6 +103,7 @@ $(OUTPUT)/test_netcnt: cgroup_helpers.c
$(OUTPUT)/test_sock_fields: cgroup_helpers.c
$(OUTPUT)/test_sysctl: cgroup_helpers.c
$(OUTPUT)/test_cgroup_attach: cgroup_helpers.c
+$(OUTPUT)/test_sockopt: cgroup_helpers.c
.PHONY: force
diff --git a/tools/testing/selftests/bpf/test_sockopt.c b/tools/testing/selftests/bpf/test_sockopt.c
new file mode 100644
index 000000000000..23bd0819382d
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_sockopt.c
@@ -0,0 +1,1021 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+
+#include <linux/filter.h>
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
+
+#include "bpf_rlimit.h"
+#include "bpf_util.h"
+#include "cgroup_helpers.h"
+
+#define CG_PATH "/sockopt"
+
+static char bpf_log_buf[4096];
+static bool verbose;
+
+enum sockopt_test_error {
+ OK = 0,
+ DENY_LOAD,
+ DENY_ATTACH,
+ EPERM_GETSOCKOPT,
+ EFAULT_GETSOCKOPT,
+ EPERM_SETSOCKOPT,
+ EFAULT_SETSOCKOPT,
+};
+
+static struct sockopt_test {
+ const char *descr;
+ const struct bpf_insn insns[64];
+ enum bpf_attach_type attach_type;
+ enum bpf_attach_type expected_attach_type;
+
+ int set_optname;
+ int set_level;
+ const char set_optval[64];
+ socklen_t set_optlen;
+
+ int get_optname;
+ int get_level;
+ const char get_optval[64];
+ socklen_t get_optlen;
+ socklen_t get_optlen_ret;
+
+ enum sockopt_test_error error;
+} tests[] = {
+
+ /* ==================== getsockopt ==================== */
+
+ {
+ .descr = "getsockopt: no expected_attach_type",
+ .insns = {
+ /* return 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+
+ },
+ .attach_type = BPF_CGROUP_GETSOCKOPT,
+ .expected_attach_type = 0,
+ .error = DENY_LOAD,
+ },
+ {
+ .descr = "getsockopt: wrong expected_attach_type",
+ .insns = {
+ /* return 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+
+ },
+ .attach_type = BPF_CGROUP_GETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_SETSOCKOPT,
+ .error = DENY_ATTACH,
+ },
+ {
+ .descr = "getsockopt: bypass bpf hook",
+ .insns = {
+ /* return 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_GETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_GETSOCKOPT,
+
+ .get_level = SOL_IP,
+ .set_level = SOL_IP,
+
+ .get_optname = IP_TOS,
+ .set_optname = IP_TOS,
+
+ .set_optval = { 1 << 3 },
+ .set_optlen = 1,
+
+ .get_optval = { 1 << 3 },
+ .get_optlen = 1,
+ },
+ {
+ .descr = "getsockopt: return EPERM from bpf hook",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_GETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_GETSOCKOPT,
+
+ .get_level = SOL_IP,
+ .get_optname = IP_TOS,
+
+ .get_optlen = 1,
+ .error = EPERM_GETSOCKOPT,
+ },
+ {
+ .descr = "getsockopt: no optval bounds check, deny loading",
+ .insns = {
+ /* r6 = ctx->optval */
+ BPF_LDX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1,
+ offsetof(struct bpf_sockopt, optval)),
+
+ /* ctx->optval[0] = 0x80 */
+ BPF_MOV64_IMM(BPF_REG_0, 0x80),
+ BPF_STX_MEM(BPF_W, BPF_REG_6, BPF_REG_0, 0),
+
+ /* return 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_GETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_GETSOCKOPT,
+ .error = DENY_LOAD,
+ },
+ {
+ .descr = "getsockopt: read ctx->level",
+ .insns = {
+ /* r6 = ctx->level */
+ BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1,
+ offsetof(struct bpf_sockopt, level)),
+
+ /* if (ctx->level == 123) { */
+ BPF_JMP_IMM(BPF_JNE, BPF_REG_6, 123, 4),
+ /* ctx->retval = 0 */
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct bpf_sockopt, retval)),
+ /* return 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_JMP_A(1),
+ /* } else { */
+ /* return 0 */
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ /* } */
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_GETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_GETSOCKOPT,
+
+ .get_level = 123,
+
+ .get_optlen = 1,
+ },
+ {
+ .descr = "getsockopt: deny writing to ctx->level",
+ .insns = {
+ /* ctx->level = 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct bpf_sockopt, level)),
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_GETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_GETSOCKOPT,
+
+ .error = DENY_LOAD,
+ },
+ {
+ .descr = "getsockopt: read ctx->optname",
+ .insns = {
+ /* r6 = ctx->optname */
+ BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1,
+ offsetof(struct bpf_sockopt, optname)),
+
+ /* if (ctx->optname == 123) { */
+ BPF_JMP_IMM(BPF_JNE, BPF_REG_6, 123, 4),
+ /* ctx->retval = 0 */
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct bpf_sockopt, retval)),
+ /* return 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_JMP_A(1),
+ /* } else { */
+ /* return 0 */
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ /* } */
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_GETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_GETSOCKOPT,
+
+ .get_optname = 123,
+
+ .get_optlen = 1,
+ },
+ {
+ .descr = "getsockopt: read ctx->retval",
+ .insns = {
+ /* r6 = ctx->retval */
+ BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1,
+ offsetof(struct bpf_sockopt, retval)),
+
+ /* return 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_GETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_GETSOCKOPT,
+
+ .get_level = SOL_IP,
+ .get_optname = IP_TOS,
+ .get_optlen = 1,
+ },
+ {
+ .descr = "getsockopt: deny writing to ctx->optname",
+ .insns = {
+ /* ctx->optname = 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct bpf_sockopt, optname)),
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_GETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_GETSOCKOPT,
+
+ .error = DENY_LOAD,
+ },
+ {
+ .descr = "getsockopt: read ctx->optlen",
+ .insns = {
+ /* r6 = ctx->optlen */
+ BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1,
+ offsetof(struct bpf_sockopt, optlen)),
+
+ /* if (ctx->optlen == 64) { */
+ BPF_JMP_IMM(BPF_JNE, BPF_REG_6, 64, 4),
+ /* ctx->retval = 0 */
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct bpf_sockopt, retval)),
+ /* return 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_JMP_A(1),
+ /* } else { */
+ /* return 0 */
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ /* } */
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_GETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_GETSOCKOPT,
+
+ .get_optlen = 64,
+ },
+ {
+ .descr = "getsockopt: deny bigger ctx->optlen",
+ .insns = {
+ /* ctx->optlen = 65 */
+ BPF_MOV64_IMM(BPF_REG_0, 65),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct bpf_sockopt, optlen)),
+
+ /* ctx->retval = 0 */
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct bpf_sockopt, retval)),
+
+ /* return 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_GETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_GETSOCKOPT,
+
+ .get_optlen = 64,
+
+ .error = EFAULT_GETSOCKOPT,
+ },
+ {
+ .descr = "getsockopt: deny arbitrary ctx->retval",
+ .insns = {
+ /* ctx->retval = 123 */
+ BPF_MOV64_IMM(BPF_REG_0, 123),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct bpf_sockopt, retval)),
+
+ /* return 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_GETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_GETSOCKOPT,
+
+ .get_optlen = 64,
+
+ .error = EFAULT_GETSOCKOPT,
+ },
+ {
+ .descr = "getsockopt: support smaller ctx->optlen",
+ .insns = {
+ /* ctx->optlen = 32 */
+ BPF_MOV64_IMM(BPF_REG_0, 32),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct bpf_sockopt, optlen)),
+ /* ctx->retval = 0 */
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct bpf_sockopt, retval)),
+ /* return 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_GETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_GETSOCKOPT,
+
+ .get_optlen = 64,
+ .get_optlen_ret = 32,
+ },
+ {
+ .descr = "getsockopt: deny writing to ctx->optval",
+ .insns = {
+ /* ctx->optval = 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0,
+ offsetof(struct bpf_sockopt, optval)),
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_GETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_GETSOCKOPT,
+
+ .error = DENY_LOAD,
+ },
+ {
+ .descr = "getsockopt: deny writing to ctx->optval_end",
+ .insns = {
+ /* ctx->optval_end = 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0,
+ offsetof(struct bpf_sockopt, optval_end)),
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_GETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_GETSOCKOPT,
+
+ .error = DENY_LOAD,
+ },
+ {
+ .descr = "getsockopt: rewrite value",
+ .insns = {
+ /* r6 = ctx->optval */
+ BPF_LDX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1,
+ offsetof(struct bpf_sockopt, optval)),
+ /* r2 = ctx->optval */
+ BPF_MOV64_REG(BPF_REG_2, BPF_REG_6),
+ /* r6 = ctx->optval + 1 */
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_6, 1),
+
+ /* r7 = ctx->optval_end */
+ BPF_LDX_MEM(BPF_DW, BPF_REG_7, BPF_REG_1,
+ offsetof(struct bpf_sockopt, optval_end)),
+
+ /* if (ctx->optval + 1 <= ctx->optval_end) { */
+ BPF_JMP_REG(BPF_JGT, BPF_REG_6, BPF_REG_7, 1),
+ /* ctx->optval[0] = 0xF0 */
+ BPF_ST_MEM(BPF_B, BPF_REG_2, 0, 0xF0),
+ /* } */
+
+ /* ctx->retval = 0 */
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct bpf_sockopt, retval)),
+
+ /* return 1*/
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_GETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_GETSOCKOPT,
+
+ .get_level = SOL_IP,
+ .get_optname = IP_TOS,
+
+ .get_optval = { 0xF0 },
+ .get_optlen = 1,
+ },
+
+ /* ==================== setsockopt ==================== */
+
+ {
+ .descr = "setsockopt: no expected_attach_type",
+ .insns = {
+ /* return 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+
+ },
+ .attach_type = BPF_CGROUP_SETSOCKOPT,
+ .expected_attach_type = 0,
+ .error = DENY_LOAD,
+ },
+ {
+ .descr = "setsockopt: wrong expected_attach_type",
+ .insns = {
+ /* return 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+
+ },
+ .attach_type = BPF_CGROUP_SETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_GETSOCKOPT,
+ .error = DENY_ATTACH,
+ },
+ {
+ .descr = "setsockopt: bypass bpf hook",
+ .insns = {
+ /* return 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_SETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_SETSOCKOPT,
+
+ .get_level = SOL_IP,
+ .set_level = SOL_IP,
+
+ .get_optname = IP_TOS,
+ .set_optname = IP_TOS,
+
+ .set_optval = { 1 << 3 },
+ .set_optlen = 1,
+
+ .get_optval = { 1 << 3 },
+ .get_optlen = 1,
+ },
+ {
+ .descr = "setsockopt: return EPERM from bpf hook",
+ .insns = {
+ /* return 0 */
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_SETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_SETSOCKOPT,
+
+ .set_level = SOL_IP,
+ .set_optname = IP_TOS,
+
+ .set_optlen = 1,
+ .error = EPERM_SETSOCKOPT,
+ },
+ {
+ .descr = "setsockopt: no optval bounds check, deny loading",
+ .insns = {
+ /* r6 = ctx->optval */
+ BPF_LDX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1,
+ offsetof(struct bpf_sockopt, optval)),
+
+ /* r0 = ctx->optval[0] */
+ BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_6, 0),
+
+ /* return 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_SETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_SETSOCKOPT,
+ .error = DENY_LOAD,
+ },
+ {
+ .descr = "setsockopt: read ctx->level",
+ .insns = {
+ /* r6 = ctx->level */
+ BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1,
+ offsetof(struct bpf_sockopt, level)),
+
+ /* if (ctx->level == 123) { */
+ BPF_JMP_IMM(BPF_JNE, BPF_REG_6, 123, 4),
+ /* ctx->optlen = -1 */
+ BPF_MOV64_IMM(BPF_REG_0, -1),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct bpf_sockopt, optlen)),
+ /* return 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_JMP_A(1),
+ /* } else { */
+ /* return 0 */
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ /* } */
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_SETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_SETSOCKOPT,
+
+ .set_level = 123,
+
+ .set_optlen = 1,
+ },
+ {
+ .descr = "setsockopt: allow changing ctx->level",
+ .insns = {
+ /* ctx->level = SOL_IP */
+ BPF_MOV64_IMM(BPF_REG_0, SOL_IP),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct bpf_sockopt, level)),
+ /* return 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_SETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_SETSOCKOPT,
+
+ .get_level = SOL_IP,
+ .set_level = 234, /* should be rewritten to SOL_IP */
+
+ .get_optname = IP_TOS,
+ .set_optname = IP_TOS,
+
+ .set_optval = { 1 << 3 },
+ .set_optlen = 1,
+ .get_optval = { 1 << 3 },
+ .get_optlen = 1,
+ },
+ {
+ .descr = "setsockopt: read ctx->optname",
+ .insns = {
+ /* r6 = ctx->optname */
+ BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1,
+ offsetof(struct bpf_sockopt, optname)),
+
+ /* if (ctx->optname == 123) { */
+ BPF_JMP_IMM(BPF_JNE, BPF_REG_6, 123, 4),
+ /* ctx->optlen = -1 */
+ BPF_MOV64_IMM(BPF_REG_0, -1),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct bpf_sockopt, optlen)),
+ /* return 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_JMP_A(1),
+ /* } else { */
+ /* return 0 */
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ /* } */
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_SETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_SETSOCKOPT,
+
+ .set_optname = 123,
+
+ .set_optlen = 1,
+ },
+ {
+ .descr = "setsockopt: allow changing ctx->optname",
+ .insns = {
+ /* ctx->optname = IP_TOS */
+ BPF_MOV64_IMM(BPF_REG_0, IP_TOS),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct bpf_sockopt, optname)),
+ /* return 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_SETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_SETSOCKOPT,
+
+ .get_level = SOL_IP,
+ .set_level = SOL_IP,
+
+ .get_optname = IP_TOS,
+ .set_optname = 456, /* should be rewritten to IP_TOS */
+
+ .set_optval = { 1 << 3 },
+ .set_optlen = 1,
+ .get_optval = { 1 << 3 },
+ .get_optlen = 1,
+ },
+ {
+ .descr = "setsockopt: read ctx->optlen",
+ .insns = {
+ /* r6 = ctx->optlen */
+ BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1,
+ offsetof(struct bpf_sockopt, optlen)),
+
+ /* if (ctx->optlen == 64) { */
+ BPF_JMP_IMM(BPF_JNE, BPF_REG_6, 64, 4),
+ /* ctx->optlen = -1 */
+ BPF_MOV64_IMM(BPF_REG_0, -1),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct bpf_sockopt, optlen)),
+ /* return 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_JMP_A(1),
+ /* } else { */
+ /* return 0 */
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ /* } */
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_SETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_SETSOCKOPT,
+
+ .set_optlen = 64,
+ },
+ {
+ .descr = "setsockopt: ctx->optlen == -1 is ok",
+ .insns = {
+ /* ctx->optlen = -1 */
+ BPF_MOV64_IMM(BPF_REG_0, -1),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct bpf_sockopt, optlen)),
+ /* return 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_SETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_SETSOCKOPT,
+
+ .set_optlen = 64,
+ },
+ {
+ .descr = "setsockopt: deny ctx->optlen < 0 (except -1)",
+ .insns = {
+ /* ctx->optlen = -2 */
+ BPF_MOV64_IMM(BPF_REG_0, -2),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct bpf_sockopt, optlen)),
+ /* return 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_SETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_SETSOCKOPT,
+
+ .set_optlen = 4,
+
+ .error = EFAULT_SETSOCKOPT,
+ },
+ {
+ .descr = "setsockopt: deny ctx->optlen > input optlen",
+ .insns = {
+ /* ctx->optlen = 65 */
+ BPF_MOV64_IMM(BPF_REG_0, 65),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct bpf_sockopt, optlen)),
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_SETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_SETSOCKOPT,
+
+ .set_optlen = 64,
+
+ .error = EFAULT_SETSOCKOPT,
+ },
+ {
+ .descr = "setsockopt: allow changing ctx->optlen within bounds",
+ .insns = {
+ /* r6 = ctx->optval */
+ BPF_LDX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1,
+ offsetof(struct bpf_sockopt, optval)),
+ /* r2 = ctx->optval */
+ BPF_MOV64_REG(BPF_REG_2, BPF_REG_6),
+ /* r6 = ctx->optval + 1 */
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_6, 1),
+
+ /* r7 = ctx->optval_end */
+ BPF_LDX_MEM(BPF_DW, BPF_REG_7, BPF_REG_1,
+ offsetof(struct bpf_sockopt, optval_end)),
+
+ /* if (ctx->optval + 1 <= ctx->optval_end) { */
+ BPF_JMP_REG(BPF_JGT, BPF_REG_6, BPF_REG_7, 1),
+ /* ctx->optval[0] = 1 << 3 */
+ BPF_ST_MEM(BPF_B, BPF_REG_2, 0, 1 << 3),
+ /* } */
+
+ /* ctx->optlen = 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct bpf_sockopt, optlen)),
+
+ /* return 1*/
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_SETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_SETSOCKOPT,
+
+ .get_level = SOL_IP,
+ .set_level = SOL_IP,
+
+ .get_optname = IP_TOS,
+ .set_optname = IP_TOS,
+
+ .set_optval = { 1, 1, 1, 1 },
+ .set_optlen = 4,
+ .get_optval = { 1 << 3 },
+ .get_optlen = 1,
+ },
+ {
+ .descr = "setsockopt: deny write ctx->retval",
+ .insns = {
+ /* ctx->retval = 0 */
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct bpf_sockopt, retval)),
+
+ /* return 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_SETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_SETSOCKOPT,
+
+ .error = DENY_LOAD,
+ },
+ {
+ .descr = "setsockopt: deny read ctx->retval",
+ .insns = {
+ /* r6 = ctx->retval */
+ BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1,
+ offsetof(struct bpf_sockopt, retval)),
+
+ /* return 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_SETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_SETSOCKOPT,
+
+ .error = DENY_LOAD,
+ },
+ {
+ .descr = "setsockopt: deny writing to ctx->optval",
+ .insns = {
+ /* ctx->optval = 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0,
+ offsetof(struct bpf_sockopt, optval)),
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_SETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_SETSOCKOPT,
+
+ .error = DENY_LOAD,
+ },
+ {
+ .descr = "setsockopt: deny writing to ctx->optval_end",
+ .insns = {
+ /* ctx->optval_end = 1 */
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0,
+ offsetof(struct bpf_sockopt, optval_end)),
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_SETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_SETSOCKOPT,
+
+ .error = DENY_LOAD,
+ },
+ {
+ .descr = "setsockopt: allow IP_TOS <= 128",
+ .insns = {
+ /* r6 = ctx->optval */
+ BPF_LDX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1,
+ offsetof(struct bpf_sockopt, optval)),
+ /* r7 = ctx->optval + 1 */
+ BPF_MOV64_REG(BPF_REG_7, BPF_REG_6),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, 1),
+
+ /* r8 = ctx->optval_end */
+ BPF_LDX_MEM(BPF_DW, BPF_REG_8, BPF_REG_1,
+ offsetof(struct bpf_sockopt, optval_end)),
+
+ /* if (ctx->optval + 1 <= ctx->optval_end) { */
+ BPF_JMP_REG(BPF_JGT, BPF_REG_7, BPF_REG_8, 4),
+
+ /* r9 = ctx->optval[0] */
+ BPF_LDX_MEM(BPF_B, BPF_REG_9, BPF_REG_6, 0),
+
+ /* if (ctx->optval[0] < 128) */
+ BPF_JMP_IMM(BPF_JGT, BPF_REG_9, 128, 2),
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_JMP_A(1),
+ /* } */
+
+ /* } else { */
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ /* } */
+
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_SETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_SETSOCKOPT,
+
+ .get_level = SOL_IP,
+ .set_level = SOL_IP,
+
+ .get_optname = IP_TOS,
+ .set_optname = IP_TOS,
+
+ .set_optval = { 0x80 },
+ .set_optlen = 1,
+ .get_optval = { 0x80 },
+ .get_optlen = 1,
+ },
+ {
+ .descr = "setsockopt: deny IP_TOS > 128",
+ .insns = {
+ /* r6 = ctx->optval */
+ BPF_LDX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1,
+ offsetof(struct bpf_sockopt, optval)),
+ /* r7 = ctx->optval + 1 */
+ BPF_MOV64_REG(BPF_REG_7, BPF_REG_6),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, 1),
+
+ /* r8 = ctx->optval_end */
+ BPF_LDX_MEM(BPF_DW, BPF_REG_8, BPF_REG_1,
+ offsetof(struct bpf_sockopt, optval_end)),
+
+ /* if (ctx->optval + 1 <= ctx->optval_end) { */
+ BPF_JMP_REG(BPF_JGT, BPF_REG_7, BPF_REG_8, 4),
+
+ /* r9 = ctx->optval[0] */
+ BPF_LDX_MEM(BPF_B, BPF_REG_9, BPF_REG_6, 0),
+
+ /* if (ctx->optval[0] < 128) */
+ BPF_JMP_IMM(BPF_JGT, BPF_REG_9, 128, 2),
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_JMP_A(1),
+ /* } */
+
+ /* } else { */
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ /* } */
+
+ BPF_EXIT_INSN(),
+ },
+ .attach_type = BPF_CGROUP_SETSOCKOPT,
+ .expected_attach_type = BPF_CGROUP_SETSOCKOPT,
+
+ .get_level = SOL_IP,
+ .set_level = SOL_IP,
+
+ .get_optname = IP_TOS,
+ .set_optname = IP_TOS,
+
+ .set_optval = { 0x81 },
+ .set_optlen = 1,
+ .get_optval = { 0x00 },
+ .get_optlen = 1,
+
+ .error = EPERM_SETSOCKOPT,
+ },
+};
+
+static int load_prog(const struct bpf_insn *insns,
+ enum bpf_attach_type expected_attach_type)
+{
+ struct bpf_load_program_attr attr = {
+ .prog_type = BPF_PROG_TYPE_CGROUP_SOCKOPT,
+ .expected_attach_type = expected_attach_type,
+ .insns = insns,
+ .license = "GPL",
+ .log_level = 2,
+ };
+ int fd;
+
+ for (;
+ insns[attr.insns_cnt].code != (BPF_JMP | BPF_EXIT);
+ attr.insns_cnt++) {
+ }
+ attr.insns_cnt++;
+
+ fd = bpf_load_program_xattr(&attr, bpf_log_buf, sizeof(bpf_log_buf));
+ if (verbose && fd < 0)
+ fprintf(stderr, "%s\n", bpf_log_buf);
+
+ return fd;
+}
+
+static int run_test(int cgroup_fd, struct sockopt_test *test)
+{
+ int sock_fd, err, prog_fd;
+ void *optval = NULL;
+ int ret = 0;
+
+ prog_fd = load_prog(test->insns, test->expected_attach_type);
+ if (prog_fd < 0) {
+ if (test->error == DENY_LOAD)
+ return 0;
+
+ log_err("Failed to load BPF program");
+ return -1;
+ }
+
+ err = bpf_prog_attach(prog_fd, cgroup_fd, test->attach_type, 0);
+ if (err < 0) {
+ if (test->error == DENY_ATTACH)
+ goto close_prog_fd;
+
+ log_err("Failed to attach BPF program");
+ ret = -1;
+ goto close_prog_fd;
+ }
+
+ sock_fd = socket(AF_INET, SOCK_STREAM, 0);
+ if (sock_fd < 0) {
+ log_err("Failed to create AF_INET socket");
+ ret = -1;
+ goto detach_prog;
+ }
+
+ if (test->set_optlen) {
+ err = setsockopt(sock_fd, test->set_level, test->set_optname,
+ test->set_optval, test->set_optlen);
+ if (err) {
+ if (errno == EPERM && test->error == EPERM_SETSOCKOPT)
+ goto close_sock_fd;
+ if (errno == EFAULT && test->error == EFAULT_SETSOCKOPT)
+ goto free_optval;
+
+ log_err("Failed to call setsockopt");
+ ret = -1;
+ goto close_sock_fd;
+ }
+ }
+
+ if (test->get_optlen) {
+ optval = malloc(test->get_optlen);
+ socklen_t optlen = test->get_optlen;
+ socklen_t expected_get_optlen = test->get_optlen_ret ?:
+ test->get_optlen;
+
+ err = getsockopt(sock_fd, test->get_level, test->get_optname,
+ optval, &optlen);
+ if (err) {
+ if (errno == EPERM && test->error == EPERM_GETSOCKOPT)
+ goto free_optval;
+ if (errno == EFAULT && test->error == EFAULT_GETSOCKOPT)
+ goto free_optval;
+
+ log_err("Failed to call getsockopt");
+ ret = -1;
+ goto free_optval;
+ }
+
+ if (optlen != expected_get_optlen) {
+ errno = 0;
+ log_err("getsockopt returned unexpected optlen");
+ ret = -1;
+ goto free_optval;
+ }
+
+ if (memcmp(optval, test->get_optval, optlen) != 0) {
+ errno = 0;
+ log_err("getsockopt returned unexpected optval");
+ ret = -1;
+ goto free_optval;
+ }
+ }
+
+ ret = test->error != OK;
+
+free_optval:
+ free(optval);
+close_sock_fd:
+ close(sock_fd);
+detach_prog:
+ bpf_prog_detach2(prog_fd, cgroup_fd, test->attach_type);
+close_prog_fd:
+ close(prog_fd);
+ return ret;
+}
+
+int main(int args, char **argv)
+{
+ int err = EXIT_FAILURE, error_cnt = 0;
+ int cgroup_fd, i;
+
+ if (setup_cgroup_environment())
+ goto cleanup_obj;
+
+ cgroup_fd = create_and_get_cgroup(CG_PATH);
+ if (cgroup_fd < 0)
+ goto cleanup_cgroup_env;
+
+ if (join_cgroup(CG_PATH))
+ goto cleanup_cgroup;
+
+ for (i = 0; i < ARRAY_SIZE(tests); i++) {
+ int err = run_test(cgroup_fd, &tests[i]);
+
+ if (err)
+ error_cnt++;
+
+ printf("#%d %s: %s\n", i, err ? "FAIL" : "PASS",
+ tests[i].descr);
+ }
+
+ printf("Summary: %ld PASSED, %d FAILED\n",
+ ARRAY_SIZE(tests) - error_cnt, error_cnt);
+ err = error_cnt ? EXIT_FAILURE : EXIT_SUCCESS;
+
+cleanup_cgroup:
+ close(cgroup_fd);
+cleanup_cgroup_env:
+ cleanup_cgroup_environment();
+cleanup_obj:
+ return err;
+}
--
2.22.0.410.gd8fdbe21b5-goog
^ permalink raw reply related [flat|nested] 13+ messages in thread
* [PATCH bpf-next v9 6/9] selftests/bpf: add sockopt test that exercises sk helpers
2019-06-27 20:38 [PATCH bpf-next v9 0/9] bpf: getsockopt and setsockopt hooks Stanislav Fomichev
` (4 preceding siblings ...)
2019-06-27 20:38 ` [PATCH bpf-next v9 5/9] selftests/bpf: add sockopt test Stanislav Fomichev
@ 2019-06-27 20:38 ` Stanislav Fomichev
2019-06-27 20:38 ` [PATCH bpf-next v9 7/9] selftests/bpf: add sockopt test that exercises BPF_F_ALLOW_MULTI Stanislav Fomichev
` (3 subsequent siblings)
9 siblings, 0 replies; 13+ messages in thread
From: Stanislav Fomichev @ 2019-06-27 20:38 UTC (permalink / raw)
To: netdev, bpf
Cc: davem, ast, daniel, Stanislav Fomichev, Andrii Nakryiko, Martin Lau
socktop test that introduces new SOL_CUSTOM sockopt level and
stores whatever users sets in sk storage. Whenever getsockopt
is called, the original value is retrieved.
v9:
* SO_SNDBUF example to override user-supplied buffer
v7:
* use retval=0 and optlen-1
v6:
* test 'ret=1' use-case as well (Alexei Starovoitov)
v4:
* don't call bpf_sk_fullsock helper
v3:
* drop (__u8 *)(long) casts for optval{,_end}
v2:
* new test
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Martin Lau <kafai@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
---
tools/testing/selftests/bpf/.gitignore | 1 +
tools/testing/selftests/bpf/Makefile | 3 +-
.../testing/selftests/bpf/progs/sockopt_sk.c | 111 +++++++++
tools/testing/selftests/bpf/test_sockopt_sk.c | 214 ++++++++++++++++++
4 files changed, 328 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/bpf/progs/sockopt_sk.c
create mode 100644 tools/testing/selftests/bpf/test_sockopt_sk.c
diff --git a/tools/testing/selftests/bpf/.gitignore b/tools/testing/selftests/bpf/.gitignore
index 3fe92601223d..8ac076c311d4 100644
--- a/tools/testing/selftests/bpf/.gitignore
+++ b/tools/testing/selftests/bpf/.gitignore
@@ -40,3 +40,4 @@ test_hashmap
test_btf_dump
xdping
test_sockopt
+test_sockopt_sk
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index 7f2210402e57..57ae4e168ace 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -26,7 +26,7 @@ TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test
test_sock test_btf test_sockmap get_cgroup_id_user test_socket_cookie \
test_cgroup_storage test_select_reuseport test_section_names \
test_netcnt test_tcpnotify_user test_sock_fields test_sysctl test_hashmap \
- test_btf_dump test_cgroup_attach xdping test_sockopt
+ test_btf_dump test_cgroup_attach xdping test_sockopt test_sockopt_sk
BPF_OBJ_FILES = $(patsubst %.c,%.o, $(notdir $(wildcard progs/*.c)))
TEST_GEN_FILES = $(BPF_OBJ_FILES)
@@ -104,6 +104,7 @@ $(OUTPUT)/test_sock_fields: cgroup_helpers.c
$(OUTPUT)/test_sysctl: cgroup_helpers.c
$(OUTPUT)/test_cgroup_attach: cgroup_helpers.c
$(OUTPUT)/test_sockopt: cgroup_helpers.c
+$(OUTPUT)/test_sockopt_sk: cgroup_helpers.c
.PHONY: force
diff --git a/tools/testing/selftests/bpf/progs/sockopt_sk.c b/tools/testing/selftests/bpf/progs/sockopt_sk.c
new file mode 100644
index 000000000000..076122c898e9
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/sockopt_sk.c
@@ -0,0 +1,111 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <netinet/in.h>
+#include <linux/bpf.h>
+#include "bpf_helpers.h"
+
+char _license[] SEC("license") = "GPL";
+__u32 _version SEC("version") = 1;
+
+#define SOL_CUSTOM 0xdeadbeef
+
+struct sockopt_sk {
+ __u8 val;
+};
+
+struct bpf_map_def SEC("maps") socket_storage_map = {
+ .type = BPF_MAP_TYPE_SK_STORAGE,
+ .key_size = sizeof(int),
+ .value_size = sizeof(struct sockopt_sk),
+ .map_flags = BPF_F_NO_PREALLOC,
+};
+BPF_ANNOTATE_KV_PAIR(socket_storage_map, int, struct sockopt_sk);
+
+SEC("cgroup/getsockopt")
+int _getsockopt(struct bpf_sockopt *ctx)
+{
+ __u8 *optval_end = ctx->optval_end;
+ __u8 *optval = ctx->optval;
+ struct sockopt_sk *storage;
+
+ if (ctx->level == SOL_IP && ctx->optname == IP_TOS)
+ /* Not interested in SOL_IP:IP_TOS;
+ * let next BPF program in the cgroup chain or kernel
+ * handle it.
+ */
+ return 1;
+
+ if (ctx->level == SOL_SOCKET && ctx->optname == SO_SNDBUF) {
+ /* Not interested in SOL_SOCKET:SO_SNDBUF;
+ * let next BPF program in the cgroup chain or kernel
+ * handle it.
+ */
+ return 1;
+ }
+
+ if (ctx->level != SOL_CUSTOM)
+ return 0; /* EPERM, deny everything except custom level */
+
+ if (optval + 1 > optval_end)
+ return 0; /* EPERM, bounds check */
+
+ storage = bpf_sk_storage_get(&socket_storage_map, ctx->sk, 0,
+ BPF_SK_STORAGE_GET_F_CREATE);
+ if (!storage)
+ return 0; /* EPERM, couldn't get sk storage */
+
+ if (!ctx->retval)
+ return 0; /* EPERM, kernel should not have handled
+ * SOL_CUSTOM, something is wrong!
+ */
+ ctx->retval = 0; /* Reset system call return value to zero */
+
+ optval[0] = storage->val;
+ ctx->optlen = 1;
+
+ return 1;
+}
+
+SEC("cgroup/setsockopt")
+int _setsockopt(struct bpf_sockopt *ctx)
+{
+ __u8 *optval_end = ctx->optval_end;
+ __u8 *optval = ctx->optval;
+ struct sockopt_sk *storage;
+
+ if (ctx->level == SOL_IP && ctx->optname == IP_TOS)
+ /* Not interested in SOL_IP:IP_TOS;
+ * let next BPF program in the cgroup chain or kernel
+ * handle it.
+ */
+ return 1;
+
+ if (ctx->level == SOL_SOCKET && ctx->optname == SO_SNDBUF) {
+ /* Overwrite SO_SNDBUF value */
+
+ if (optval + sizeof(__u32) > optval_end)
+ return 0; /* EPERM, bounds check */
+
+ *(__u32 *)optval = 0x55AA;
+ ctx->optlen = 4;
+
+ return 1;
+ }
+
+ if (ctx->level != SOL_CUSTOM)
+ return 0; /* EPERM, deny everything except custom level */
+
+ if (optval + 1 > optval_end)
+ return 0; /* EPERM, bounds check */
+
+ storage = bpf_sk_storage_get(&socket_storage_map, ctx->sk, 0,
+ BPF_SK_STORAGE_GET_F_CREATE);
+ if (!storage)
+ return 0; /* EPERM, couldn't get sk storage */
+
+ storage->val = optval[0];
+ ctx->optlen = -1; /* BPF has consumed this option, don't call kernel
+ * setsockopt handler.
+ */
+
+ return 1;
+}
diff --git a/tools/testing/selftests/bpf/test_sockopt_sk.c b/tools/testing/selftests/bpf/test_sockopt_sk.c
new file mode 100644
index 000000000000..12e79ed075ce
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_sockopt_sk.c
@@ -0,0 +1,214 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+
+#include <linux/filter.h>
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
+
+#include "bpf_rlimit.h"
+#include "bpf_util.h"
+#include "cgroup_helpers.h"
+
+#define CG_PATH "/sockopt"
+
+#define SOL_CUSTOM 0xdeadbeef
+
+static int getsetsockopt(void)
+{
+ int fd, err;
+ char buf[4] = {};
+ socklen_t optlen;
+
+ fd = socket(AF_INET, SOCK_STREAM, 0);
+ if (fd < 0) {
+ log_err("Failed to create socket");
+ return -1;
+ }
+
+ /* IP_TOS - BPF bypass */
+
+ buf[0] = 0x08;
+ err = setsockopt(fd, SOL_IP, IP_TOS, buf, 1);
+ if (err) {
+ log_err("Failed to call setsockopt(IP_TOS)");
+ goto err;
+ }
+
+ buf[0] = 0x00;
+ optlen = 1;
+ err = getsockopt(fd, SOL_IP, IP_TOS, buf, &optlen);
+ if (err) {
+ log_err("Failed to call getsockopt(IP_TOS)");
+ goto err;
+ }
+
+ if (buf[0] != 0x08) {
+ log_err("Unexpected getsockopt(IP_TOS) buf[0] 0x%02x != 0x08",
+ buf[0]);
+ goto err;
+ }
+
+ /* IP_TTL - EPERM */
+
+ buf[0] = 1;
+ err = setsockopt(fd, SOL_IP, IP_TTL, buf, 1);
+ if (!err || errno != EPERM) {
+ log_err("Unexpected success from setsockopt(IP_TTL)");
+ goto err;
+ }
+
+ /* SOL_CUSTOM - handled by BPF */
+
+ buf[0] = 0x01;
+ err = setsockopt(fd, SOL_CUSTOM, 0, buf, 1);
+ if (err) {
+ log_err("Failed to call setsockopt");
+ goto err;
+ }
+
+ buf[0] = 0x00;
+ optlen = 4;
+ err = getsockopt(fd, SOL_CUSTOM, 0, buf, &optlen);
+ if (err) {
+ log_err("Failed to call getsockopt");
+ goto err;
+ }
+
+ if (optlen != 1) {
+ log_err("Unexpected optlen %d != 1", optlen);
+ goto err;
+ }
+ if (buf[0] != 0x01) {
+ log_err("Unexpected buf[0] 0x%02x != 0x01", buf[0]);
+ goto err;
+ }
+
+ /* SO_SNDBUF is overwritten */
+
+ buf[0] = 0x01;
+ buf[1] = 0x01;
+ buf[2] = 0x01;
+ buf[3] = 0x01;
+ err = setsockopt(fd, SOL_SOCKET, SO_SNDBUF, buf, 4);
+ if (err) {
+ log_err("Failed to call setsockopt(SO_SNDBUF)");
+ goto err;
+ }
+
+ buf[0] = 0x00;
+ buf[1] = 0x00;
+ buf[2] = 0x00;
+ buf[3] = 0x00;
+ optlen = 4;
+ err = getsockopt(fd, SOL_SOCKET, SO_SNDBUF, buf, &optlen);
+ if (err) {
+ log_err("Failed to call getsockopt(SO_SNDBUF)");
+ goto err;
+ }
+
+ if (*(__u32 *)buf != 0x55AA*2) {
+ log_err("Unexpected getsockopt(SO_SNDBUF) 0x%x != 0x55AA*2",
+ *(__u32 *)buf);
+ goto err;
+ }
+
+ close(fd);
+ return 0;
+err:
+ close(fd);
+ return -1;
+}
+
+static int prog_attach(struct bpf_object *obj, int cgroup_fd, const char *title)
+{
+ enum bpf_attach_type attach_type;
+ enum bpf_prog_type prog_type;
+ struct bpf_program *prog;
+ int err;
+
+ err = libbpf_prog_type_by_name(title, &prog_type, &attach_type);
+ if (err) {
+ log_err("Failed to deduct types for %s BPF program", title);
+ return -1;
+ }
+
+ prog = bpf_object__find_program_by_title(obj, title);
+ if (!prog) {
+ log_err("Failed to find %s BPF program", title);
+ return -1;
+ }
+
+ err = bpf_prog_attach(bpf_program__fd(prog), cgroup_fd,
+ attach_type, 0);
+ if (err) {
+ log_err("Failed to attach %s BPF program", title);
+ return -1;
+ }
+
+ return 0;
+}
+
+static int run_test(int cgroup_fd)
+{
+ struct bpf_prog_load_attr attr = {
+ .file = "./sockopt_sk.o",
+ };
+ struct bpf_object *obj;
+ int ignored;
+ int err;
+
+ err = bpf_prog_load_xattr(&attr, &obj, &ignored);
+ if (err) {
+ log_err("Failed to load BPF object");
+ return -1;
+ }
+
+ err = prog_attach(obj, cgroup_fd, "cgroup/getsockopt");
+ if (err)
+ goto close_bpf_object;
+
+ err = prog_attach(obj, cgroup_fd, "cgroup/setsockopt");
+ if (err)
+ goto close_bpf_object;
+
+ err = getsetsockopt();
+
+close_bpf_object:
+ bpf_object__close(obj);
+ return err;
+}
+
+int main(int args, char **argv)
+{
+ int cgroup_fd;
+ int err = EXIT_SUCCESS;
+
+ if (setup_cgroup_environment())
+ goto cleanup_obj;
+
+ cgroup_fd = create_and_get_cgroup(CG_PATH);
+ if (cgroup_fd < 0)
+ goto cleanup_cgroup_env;
+
+ if (join_cgroup(CG_PATH))
+ goto cleanup_cgroup;
+
+ if (run_test(cgroup_fd))
+ err = EXIT_FAILURE;
+
+ printf("test_sockopt_sk: %s\n",
+ err == EXIT_SUCCESS ? "PASSED" : "FAILED");
+
+cleanup_cgroup:
+ close(cgroup_fd);
+cleanup_cgroup_env:
+ cleanup_cgroup_environment();
+cleanup_obj:
+ return err;
+}
--
2.22.0.410.gd8fdbe21b5-goog
^ permalink raw reply related [flat|nested] 13+ messages in thread
* [PATCH bpf-next v9 7/9] selftests/bpf: add sockopt test that exercises BPF_F_ALLOW_MULTI
2019-06-27 20:38 [PATCH bpf-next v9 0/9] bpf: getsockopt and setsockopt hooks Stanislav Fomichev
` (5 preceding siblings ...)
2019-06-27 20:38 ` [PATCH bpf-next v9 6/9] selftests/bpf: add sockopt test that exercises sk helpers Stanislav Fomichev
@ 2019-06-27 20:38 ` Stanislav Fomichev
2019-06-27 20:38 ` [PATCH bpf-next v9 8/9] bpf: add sockopt documentation Stanislav Fomichev
` (2 subsequent siblings)
9 siblings, 0 replies; 13+ messages in thread
From: Stanislav Fomichev @ 2019-06-27 20:38 UTC (permalink / raw)
To: netdev, bpf
Cc: davem, ast, daniel, Stanislav Fomichev, Andrii Nakryiko, Martin Lau
sockopt test that verifies chaining behavior.
v9:
* setsockopt chaining example
v7:
* rework the test to verify cgroup getsockopt chaining
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Martin Lau <kafai@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
---
tools/testing/selftests/bpf/.gitignore | 1 +
tools/testing/selftests/bpf/Makefile | 4 +-
.../selftests/bpf/progs/sockopt_multi.c | 71 ++++
.../selftests/bpf/test_sockopt_multi.c | 374 ++++++++++++++++++
4 files changed, 449 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/bpf/progs/sockopt_multi.c
create mode 100644 tools/testing/selftests/bpf/test_sockopt_multi.c
diff --git a/tools/testing/selftests/bpf/.gitignore b/tools/testing/selftests/bpf/.gitignore
index 8ac076c311d4..a2f7f79c7908 100644
--- a/tools/testing/selftests/bpf/.gitignore
+++ b/tools/testing/selftests/bpf/.gitignore
@@ -41,3 +41,4 @@ test_btf_dump
xdping
test_sockopt
test_sockopt_sk
+test_sockopt_multi
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index 57ae4e168ace..de1754a8f5fe 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -26,7 +26,8 @@ TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test
test_sock test_btf test_sockmap get_cgroup_id_user test_socket_cookie \
test_cgroup_storage test_select_reuseport test_section_names \
test_netcnt test_tcpnotify_user test_sock_fields test_sysctl test_hashmap \
- test_btf_dump test_cgroup_attach xdping test_sockopt test_sockopt_sk
+ test_btf_dump test_cgroup_attach xdping test_sockopt test_sockopt_sk \
+ test_sockopt_multi
BPF_OBJ_FILES = $(patsubst %.c,%.o, $(notdir $(wildcard progs/*.c)))
TEST_GEN_FILES = $(BPF_OBJ_FILES)
@@ -105,6 +106,7 @@ $(OUTPUT)/test_sysctl: cgroup_helpers.c
$(OUTPUT)/test_cgroup_attach: cgroup_helpers.c
$(OUTPUT)/test_sockopt: cgroup_helpers.c
$(OUTPUT)/test_sockopt_sk: cgroup_helpers.c
+$(OUTPUT)/test_sockopt_multi: cgroup_helpers.c
.PHONY: force
diff --git a/tools/testing/selftests/bpf/progs/sockopt_multi.c b/tools/testing/selftests/bpf/progs/sockopt_multi.c
new file mode 100644
index 000000000000..4afd2595c08e
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/sockopt_multi.c
@@ -0,0 +1,71 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <netinet/in.h>
+#include <linux/bpf.h>
+#include "bpf_helpers.h"
+
+char _license[] SEC("license") = "GPL";
+__u32 _version SEC("version") = 1;
+
+SEC("cgroup/getsockopt/child")
+int _getsockopt_child(struct bpf_sockopt *ctx)
+{
+ __u8 *optval_end = ctx->optval_end;
+ __u8 *optval = ctx->optval;
+
+ if (ctx->level != SOL_IP || ctx->optname != IP_TOS)
+ return 1;
+
+ if (optval + 1 > optval_end)
+ return 0; /* EPERM, bounds check */
+
+ if (optval[0] != 0x80)
+ return 0; /* EPERM, unexpected optval from the kernel */
+
+ ctx->retval = 0; /* Reset system call return value to zero */
+
+ optval[0] = 0x90;
+ ctx->optlen = 1;
+
+ return 1;
+}
+
+SEC("cgroup/getsockopt/parent")
+int _getsockopt_parent(struct bpf_sockopt *ctx)
+{
+ __u8 *optval_end = ctx->optval_end;
+ __u8 *optval = ctx->optval;
+
+ if (ctx->level != SOL_IP || ctx->optname != IP_TOS)
+ return 1;
+
+ if (optval + 1 > optval_end)
+ return 0; /* EPERM, bounds check */
+
+ if (optval[0] != 0x90)
+ return 0; /* EPERM, unexpected optval from the kernel */
+
+ ctx->retval = 0; /* Reset system call return value to zero */
+
+ optval[0] = 0xA0;
+ ctx->optlen = 1;
+
+ return 1;
+}
+
+SEC("cgroup/setsockopt")
+int _setsockopt(struct bpf_sockopt *ctx)
+{
+ __u8 *optval_end = ctx->optval_end;
+ __u8 *optval = ctx->optval;
+
+ if (ctx->level != SOL_IP || ctx->optname != IP_TOS)
+ return 1;
+
+ if (optval + 1 > optval_end)
+ return 0; /* EPERM, bounds check */
+
+ optval[0] += 0x10;
+ ctx->optlen = 1;
+
+ return 1;
+}
diff --git a/tools/testing/selftests/bpf/test_sockopt_multi.c b/tools/testing/selftests/bpf/test_sockopt_multi.c
new file mode 100644
index 000000000000..4be3441db867
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_sockopt_multi.c
@@ -0,0 +1,374 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <error.h>
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+
+#include <linux/filter.h>
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
+
+#include "bpf_rlimit.h"
+#include "bpf_util.h"
+#include "cgroup_helpers.h"
+
+static int prog_attach(struct bpf_object *obj, int cgroup_fd, const char *title)
+{
+ enum bpf_attach_type attach_type;
+ enum bpf_prog_type prog_type;
+ struct bpf_program *prog;
+ int err;
+
+ err = libbpf_prog_type_by_name(title, &prog_type, &attach_type);
+ if (err) {
+ log_err("Failed to deduct types for %s BPF program", title);
+ return -1;
+ }
+
+ prog = bpf_object__find_program_by_title(obj, title);
+ if (!prog) {
+ log_err("Failed to find %s BPF program", title);
+ return -1;
+ }
+
+ err = bpf_prog_attach(bpf_program__fd(prog), cgroup_fd,
+ attach_type, BPF_F_ALLOW_MULTI);
+ if (err) {
+ log_err("Failed to attach %s BPF program", title);
+ return -1;
+ }
+
+ return 0;
+}
+
+static int prog_detach(struct bpf_object *obj, int cgroup_fd, const char *title)
+{
+ enum bpf_attach_type attach_type;
+ enum bpf_prog_type prog_type;
+ struct bpf_program *prog;
+ int err;
+
+ err = libbpf_prog_type_by_name(title, &prog_type, &attach_type);
+ if (err)
+ return -1;
+
+ prog = bpf_object__find_program_by_title(obj, title);
+ if (!prog)
+ return -1;
+
+ err = bpf_prog_detach2(bpf_program__fd(prog), cgroup_fd,
+ attach_type);
+ if (err)
+ return -1;
+
+ return 0;
+}
+
+static int run_getsockopt_test(struct bpf_object *obj, int cg_parent,
+ int cg_child, int sock_fd)
+{
+ socklen_t optlen;
+ __u8 buf;
+ int err;
+
+ /* Set IP_TOS to the expected value (0x80). */
+
+ buf = 0x80;
+ err = setsockopt(sock_fd, SOL_IP, IP_TOS, &buf, 1);
+ if (err < 0) {
+ log_err("Failed to call setsockopt(IP_TOS)");
+ goto detach;
+ }
+
+ buf = 0x00;
+ optlen = 1;
+ err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
+ if (err) {
+ log_err("Failed to call getsockopt(IP_TOS)");
+ goto detach;
+ }
+
+ if (buf != 0x80) {
+ log_err("Unexpected getsockopt 0x%x != 0x80 without BPF", buf);
+ err = -1;
+ goto detach;
+ }
+
+ /* Attach child program and make sure it returns new value:
+ * - kernel: -> 0x80
+ * - child: 0x80 -> 0x90
+ */
+
+ err = prog_attach(obj, cg_child, "cgroup/getsockopt/child");
+ if (err)
+ goto detach;
+
+ buf = 0x00;
+ optlen = 1;
+ err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
+ if (err) {
+ log_err("Failed to call getsockopt(IP_TOS)");
+ goto detach;
+ }
+
+ if (buf != 0x90) {
+ log_err("Unexpected getsockopt 0x%x != 0x90", buf);
+ err = -1;
+ goto detach;
+ }
+
+ /* Attach parent program and make sure it returns new value:
+ * - kernel: -> 0x80
+ * - child: 0x80 -> 0x90
+ * - parent: 0x90 -> 0xA0
+ */
+
+ err = prog_attach(obj, cg_parent, "cgroup/getsockopt/parent");
+ if (err)
+ goto detach;
+
+ buf = 0x00;
+ optlen = 1;
+ err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
+ if (err) {
+ log_err("Failed to call getsockopt(IP_TOS)");
+ goto detach;
+ }
+
+ if (buf != 0xA0) {
+ log_err("Unexpected getsockopt 0x%x != 0xA0", buf);
+ err = -1;
+ goto detach;
+ }
+
+ /* Setting unexpected initial sockopt should return EPERM:
+ * - kernel: -> 0x40
+ * - child: unexpected 0x40, EPERM
+ * - parent: unexpected 0x40, EPERM
+ */
+
+ buf = 0x40;
+ if (setsockopt(sock_fd, SOL_IP, IP_TOS, &buf, 1) < 0) {
+ log_err("Failed to call setsockopt(IP_TOS)");
+ goto detach;
+ }
+
+ buf = 0x00;
+ optlen = 1;
+ err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
+ if (!err) {
+ log_err("Unexpected success from getsockopt(IP_TOS)");
+ goto detach;
+ }
+
+ /* Detach child program and make sure we still get EPERM:
+ * - kernel: -> 0x40
+ * - parent: unexpected 0x40, EPERM
+ */
+
+ err = prog_detach(obj, cg_child, "cgroup/getsockopt/child");
+ if (err) {
+ log_err("Failed to detach child program");
+ goto detach;
+ }
+
+ buf = 0x00;
+ optlen = 1;
+ err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
+ if (!err) {
+ log_err("Unexpected success from getsockopt(IP_TOS)");
+ goto detach;
+ }
+
+ /* Set initial value to the one the parent program expects:
+ * - kernel: -> 0x90
+ * - parent: 0x90 -> 0xA0
+ */
+
+ buf = 0x90;
+ err = setsockopt(sock_fd, SOL_IP, IP_TOS, &buf, 1);
+ if (err < 0) {
+ log_err("Failed to call setsockopt(IP_TOS)");
+ goto detach;
+ }
+
+ buf = 0x00;
+ optlen = 1;
+ err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
+ if (err) {
+ log_err("Failed to call getsockopt(IP_TOS)");
+ goto detach;
+ }
+
+ if (buf != 0xA0) {
+ log_err("Unexpected getsockopt 0x%x != 0xA0", buf);
+ err = -1;
+ goto detach;
+ }
+
+detach:
+ prog_detach(obj, cg_child, "cgroup/getsockopt/child");
+ prog_detach(obj, cg_parent, "cgroup/getsockopt/parent");
+
+ return err;
+}
+
+static int run_setsockopt_test(struct bpf_object *obj, int cg_parent,
+ int cg_child, int sock_fd)
+{
+ socklen_t optlen;
+ __u8 buf;
+ int err;
+
+ /* Set IP_TOS to the expected value (0x80). */
+
+ buf = 0x80;
+ err = setsockopt(sock_fd, SOL_IP, IP_TOS, &buf, 1);
+ if (err < 0) {
+ log_err("Failed to call setsockopt(IP_TOS)");
+ goto detach;
+ }
+
+ buf = 0x00;
+ optlen = 1;
+ err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
+ if (err) {
+ log_err("Failed to call getsockopt(IP_TOS)");
+ goto detach;
+ }
+
+ if (buf != 0x80) {
+ log_err("Unexpected getsockopt 0x%x != 0x80 without BPF", buf);
+ err = -1;
+ goto detach;
+ }
+
+ /* Attach child program and make sure it adds 0x10. */
+
+ err = prog_attach(obj, cg_child, "cgroup/setsockopt");
+ if (err)
+ goto detach;
+
+ buf = 0x80;
+ err = setsockopt(sock_fd, SOL_IP, IP_TOS, &buf, 1);
+ if (err < 0) {
+ log_err("Failed to call setsockopt(IP_TOS)");
+ goto detach;
+ }
+
+ buf = 0x00;
+ optlen = 1;
+ err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
+ if (err) {
+ log_err("Failed to call getsockopt(IP_TOS)");
+ goto detach;
+ }
+
+ if (buf != 0x80 + 0x10) {
+ log_err("Unexpected getsockopt 0x%x != 0x80 + 0x10", buf);
+ err = -1;
+ goto detach;
+ }
+
+ /* Attach parent program and make sure it adds another 0x10. */
+
+ err = prog_attach(obj, cg_parent, "cgroup/setsockopt");
+ if (err)
+ goto detach;
+
+ buf = 0x80;
+ err = setsockopt(sock_fd, SOL_IP, IP_TOS, &buf, 1);
+ if (err < 0) {
+ log_err("Failed to call setsockopt(IP_TOS)");
+ goto detach;
+ }
+
+ buf = 0x00;
+ optlen = 1;
+ err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
+ if (err) {
+ log_err("Failed to call getsockopt(IP_TOS)");
+ goto detach;
+ }
+
+ if (buf != 0x80 + 2 * 0x10) {
+ log_err("Unexpected getsockopt 0x%x != 0x80 + 2 * 0x10", buf);
+ err = -1;
+ goto detach;
+ }
+
+detach:
+ prog_detach(obj, cg_child, "cgroup/setsockopt");
+ prog_detach(obj, cg_parent, "cgroup/setsockopt");
+
+ return err;
+}
+
+int main(int argc, char **argv)
+{
+ struct bpf_prog_load_attr attr = {
+ .file = "./sockopt_multi.o",
+ };
+ int cg_parent = -1, cg_child = -1;
+ struct bpf_object *obj = NULL;
+ int sock_fd = -1;
+ int err = -1;
+ int ignored;
+
+ if (setup_cgroup_environment()) {
+ log_err("Failed to setup cgroup environment\n");
+ goto out;
+ }
+
+ cg_parent = create_and_get_cgroup("/parent");
+ if (cg_parent < 0) {
+ log_err("Failed to create cgroup /parent\n");
+ goto out;
+ }
+
+ cg_child = create_and_get_cgroup("/parent/child");
+ if (cg_child < 0) {
+ log_err("Failed to create cgroup /parent/child\n");
+ goto out;
+ }
+
+ if (join_cgroup("/parent/child")) {
+ log_err("Failed to join cgroup /parent/child\n");
+ goto out;
+ }
+
+ err = bpf_prog_load_xattr(&attr, &obj, &ignored);
+ if (err) {
+ log_err("Failed to load BPF object");
+ goto out;
+ }
+
+ sock_fd = socket(AF_INET, SOCK_STREAM, 0);
+ if (sock_fd < 0) {
+ log_err("Failed to create socket");
+ goto out;
+ }
+
+ if (run_getsockopt_test(obj, cg_parent, cg_child, sock_fd))
+ err = -1;
+ printf("test_sockopt_multi: getsockopt %s\n",
+ err ? "FAILED" : "PASSED");
+
+ if (run_setsockopt_test(obj, cg_parent, cg_child, sock_fd))
+ err = -1;
+ printf("test_sockopt_multi: setsockopt %s\n",
+ err ? "FAILED" : "PASSED");
+
+out:
+ close(sock_fd);
+ bpf_object__close(obj);
+ close(cg_child);
+ close(cg_parent);
+
+ printf("test_sockopt_multi: %s\n", err ? "FAILED" : "PASSED");
+ return err ? EXIT_FAILURE : EXIT_SUCCESS;
+}
--
2.22.0.410.gd8fdbe21b5-goog
^ permalink raw reply related [flat|nested] 13+ messages in thread
* [PATCH bpf-next v9 8/9] bpf: add sockopt documentation
2019-06-27 20:38 [PATCH bpf-next v9 0/9] bpf: getsockopt and setsockopt hooks Stanislav Fomichev
` (6 preceding siblings ...)
2019-06-27 20:38 ` [PATCH bpf-next v9 7/9] selftests/bpf: add sockopt test that exercises BPF_F_ALLOW_MULTI Stanislav Fomichev
@ 2019-06-27 20:38 ` Stanislav Fomichev
2019-06-27 20:38 ` [PATCH bpf-next v9 9/9] bpftool: support cgroup sockopt Stanislav Fomichev
2019-06-27 22:31 ` [PATCH bpf-next v9 0/9] bpf: getsockopt and setsockopt hooks Alexei Starovoitov
9 siblings, 0 replies; 13+ messages in thread
From: Stanislav Fomichev @ 2019-06-27 20:38 UTC (permalink / raw)
To: netdev, bpf
Cc: davem, ast, daniel, Stanislav Fomichev, Andrii Nakryiko, Martin Lau
Provide user documentation about sockopt prog type and cgroup hooks.
v9:
* add details about setsockopt context and inheritance
v7:
* add description for retval=0 and optlen=-1
v6:
* describe cgroup chaining, add example
v2:
* use return code 2 for kernel bypass
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Martin Lau <kafai@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
---
Documentation/bpf/index.rst | 1 +
Documentation/bpf/prog_cgroup_sockopt.rst | 93 +++++++++++++++++++++++
2 files changed, 94 insertions(+)
create mode 100644 Documentation/bpf/prog_cgroup_sockopt.rst
diff --git a/Documentation/bpf/index.rst b/Documentation/bpf/index.rst
index d3fe4cac0c90..801a6ed3f2e5 100644
--- a/Documentation/bpf/index.rst
+++ b/Documentation/bpf/index.rst
@@ -42,6 +42,7 @@ Program types
.. toctree::
:maxdepth: 1
+ prog_cgroup_sockopt
prog_cgroup_sysctl
prog_flow_dissector
diff --git a/Documentation/bpf/prog_cgroup_sockopt.rst b/Documentation/bpf/prog_cgroup_sockopt.rst
new file mode 100644
index 000000000000..c47d974629ae
--- /dev/null
+++ b/Documentation/bpf/prog_cgroup_sockopt.rst
@@ -0,0 +1,93 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+============================
+BPF_PROG_TYPE_CGROUP_SOCKOPT
+============================
+
+``BPF_PROG_TYPE_CGROUP_SOCKOPT`` program type can be attached to two
+cgroup hooks:
+
+* ``BPF_CGROUP_GETSOCKOPT`` - called every time process executes ``getsockopt``
+ system call.
+* ``BPF_CGROUP_SETSOCKOPT`` - called every time process executes ``setsockopt``
+ system call.
+
+The context (``struct bpf_sockopt``) has associated socket (``sk``) and
+all input arguments: ``level``, ``optname``, ``optval`` and ``optlen``.
+
+BPF_CGROUP_SETSOCKOPT
+=====================
+
+``BPF_CGROUP_SETSOCKOPT`` is triggered *before* the kernel handling of
+sockopt and it has writable context: it can modify the supplied arguments
+before passing them down to the kernel. This hook has access to the cgroup
+and socket local storage.
+
+If BPF program sets ``optlen`` to -1, the control will be returned
+back to the userspace after all other BPF programs in the cgroup
+chain finish (i.e. kernel ``setsockopt`` handling will *not* be executed).
+
+Note, that ``optlen`` can not be increased beyond the user-supplied
+value. It can only be decreased or set to -1. Any other value will
+trigger ``EFAULT``.
+
+Return Type
+-----------
+
+* ``0`` - reject the syscall, ``EPERM`` will be returned to the userspace.
+* ``1`` - success, continue with next BPF program in the cgroup chain.
+
+BPF_CGROUP_GETSOCKOPT
+=====================
+
+``BPF_CGROUP_GETSOCKOPT`` is triggered *after* the kernel handing of
+sockopt. The BPF hook can observe ``optval``, ``optlen`` and ``retval``
+if it's interested in whatever kernel has returned. BPF hook can override
+the values above, adjust ``optlen`` and reset ``retval`` to 0. If ``optlen``
+has been increased above initial ``getsockopt`` value (i.e. userspace
+buffer is too small), ``EFAULT`` is returned.
+
+This hook has access to the cgroup and socket local storage.
+
+Note, that the only acceptable value to set to ``retval`` is 0 and the
+original value that the kernel returned. Any other value will trigger
+``EFAULT``.
+
+Return Type
+-----------
+
+* ``0`` - reject the syscall, ``EPERM`` will be returned to the userspace.
+* ``1`` - success: copy ``optval`` and ``optlen`` to userspace, return
+ ``retval`` from the syscall (note that this can be overwritten by
+ the BPF program from the parent cgroup).
+
+Cgroup Inheritance
+==================
+
+Suppose, there is the following cgroup hierarchy where each cgroup
+has ``BPF_CGROUP_GETSOCKOPT`` attached at each level with
+``BPF_F_ALLOW_MULTI`` flag::
+
+ A (root, parent)
+ \
+ B (child)
+
+When the application calls ``getsockopt`` syscall from the cgroup B,
+the programs are executed from the bottom up: B, A. First program
+(B) sees the result of kernel's ``getsockopt``. It can optionally
+adjust ``optval``, ``optlen`` and reset ``retval`` to 0. After that
+control will be passed to the second (A) program which will see the
+same context as B including any potential modifications.
+
+Same for ``BPF_CGROUP_SETSOCKOPT``: if the program is attached to
+A and B, the trigger order is B, then A. If B does any changes
+to the input arguments (``level``, ``optname``, ``optval``, ``optlen``),
+then the next program in the chain (A) will see those changes,
+*not* the original input ``setsockopt`` arguments. The potentially
+modified values will be then passed down to the kernel.
+
+Example
+=======
+
+See ``tools/testing/selftests/bpf/progs/sockopt_sk.c`` for an example
+of BPF program that handles socket options.
--
2.22.0.410.gd8fdbe21b5-goog
^ permalink raw reply related [flat|nested] 13+ messages in thread
* [PATCH bpf-next v9 9/9] bpftool: support cgroup sockopt
2019-06-27 20:38 [PATCH bpf-next v9 0/9] bpf: getsockopt and setsockopt hooks Stanislav Fomichev
` (7 preceding siblings ...)
2019-06-27 20:38 ` [PATCH bpf-next v9 8/9] bpf: add sockopt documentation Stanislav Fomichev
@ 2019-06-27 20:38 ` Stanislav Fomichev
2019-06-27 22:31 ` [PATCH bpf-next v9 0/9] bpf: getsockopt and setsockopt hooks Alexei Starovoitov
9 siblings, 0 replies; 13+ messages in thread
From: Stanislav Fomichev @ 2019-06-27 20:38 UTC (permalink / raw)
To: netdev, bpf
Cc: davem, ast, daniel, Stanislav Fomichev, Andrii Nakryiko,
Martin Lau, Jakub Kicinski
Support sockopt prog type and cgroup hooks in the bpftool.
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Martin Lau <kafai@fb.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
---
tools/bpf/bpftool/Documentation/bpftool-cgroup.rst | 7 +++++--
tools/bpf/bpftool/Documentation/bpftool-prog.rst | 3 ++-
tools/bpf/bpftool/bash-completion/bpftool | 9 ++++++---
tools/bpf/bpftool/cgroup.c | 5 ++++-
tools/bpf/bpftool/main.h | 1 +
tools/bpf/bpftool/prog.c | 3 ++-
6 files changed, 20 insertions(+), 8 deletions(-)
diff --git a/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst b/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst
index d80fdde79c22..585f270c2d25 100644
--- a/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst
+++ b/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst
@@ -29,7 +29,8 @@ CGROUP COMMANDS
| *PROG* := { **id** *PROG_ID* | **pinned** *FILE* | **tag** *PROG_TAG* }
| *ATTACH_TYPE* := { **ingress** | **egress** | **sock_create** | **sock_ops** | **device** |
| **bind4** | **bind6** | **post_bind4** | **post_bind6** | **connect4** | **connect6** |
-| **sendmsg4** | **sendmsg6** | **recvmsg4** | **recvmsg6** | **sysctl** }
+| **sendmsg4** | **sendmsg6** | **recvmsg4** | **recvmsg6** | **sysctl** |
+| **getsockopt** | **setsockopt** }
| *ATTACH_FLAGS* := { **multi** | **override** }
DESCRIPTION
@@ -90,7 +91,9 @@ DESCRIPTION
an unconnected udp4 socket (since 5.2);
**recvmsg6** call to recvfrom(2), recvmsg(2), recvmmsg(2) for
an unconnected udp6 socket (since 5.2);
- **sysctl** sysctl access (since 5.2).
+ **sysctl** sysctl access (since 5.2);
+ **getsockopt** call to getsockopt (since 5.3);
+ **setsockopt** call to setsockopt (since 5.3).
**bpftool cgroup detach** *CGROUP* *ATTACH_TYPE* *PROG*
Detach *PROG* from the cgroup *CGROUP* and attach type
diff --git a/tools/bpf/bpftool/Documentation/bpftool-prog.rst b/tools/bpf/bpftool/Documentation/bpftool-prog.rst
index 55dd06517a3b..1df637f85f94 100644
--- a/tools/bpf/bpftool/Documentation/bpftool-prog.rst
+++ b/tools/bpf/bpftool/Documentation/bpftool-prog.rst
@@ -40,7 +40,8 @@ PROG COMMANDS
| **lwt_seg6local** | **sockops** | **sk_skb** | **sk_msg** | **lirc_mode2** |
| **cgroup/bind4** | **cgroup/bind6** | **cgroup/post_bind4** | **cgroup/post_bind6** |
| **cgroup/connect4** | **cgroup/connect6** | **cgroup/sendmsg4** | **cgroup/sendmsg6** |
-| **cgroup/recvmsg4** | **cgroup/recvmsg6** | **cgroup/sysctl**
+| **cgroup/recvmsg4** | **cgroup/recvmsg6** | **cgroup/sysctl** |
+| **cgroup/getsockopt** | **cgroup/setsockopt**
| }
| *ATTACH_TYPE* := {
| **msg_verdict** | **stream_verdict** | **stream_parser** | **flow_dissector**
diff --git a/tools/bpf/bpftool/bash-completion/bpftool b/tools/bpf/bpftool/bash-completion/bpftool
index a17e84c67498..ba37095e1f62 100644
--- a/tools/bpf/bpftool/bash-completion/bpftool
+++ b/tools/bpf/bpftool/bash-completion/bpftool
@@ -379,7 +379,8 @@ _bpftool()
cgroup/sendmsg4 cgroup/sendmsg6 \
cgroup/recvmsg4 cgroup/recvmsg6 \
cgroup/post_bind4 cgroup/post_bind6 \
- cgroup/sysctl" -- \
+ cgroup/sysctl cgroup/getsockopt \
+ cgroup/setsockopt" -- \
"$cur" ) )
return 0
;;
@@ -689,7 +690,8 @@ _bpftool()
attach|detach)
local ATTACH_TYPES='ingress egress sock_create sock_ops \
device bind4 bind6 post_bind4 post_bind6 connect4 \
- connect6 sendmsg4 sendmsg6 recvmsg4 recvmsg6 sysctl'
+ connect6 sendmsg4 sendmsg6 recvmsg4 recvmsg6 sysctl \
+ getsockopt setsockopt'
local ATTACH_FLAGS='multi override'
local PROG_TYPE='id pinned tag'
case $prev in
@@ -699,7 +701,8 @@ _bpftool()
;;
ingress|egress|sock_create|sock_ops|device|bind4|bind6|\
post_bind4|post_bind6|connect4|connect6|sendmsg4|\
- sendmsg6|recvmsg4|recvmsg6|sysctl)
+ sendmsg6|recvmsg4|recvmsg6|sysctl|getsockopt|\
+ setsockopt)
COMPREPLY=( $( compgen -W "$PROG_TYPE" -- \
"$cur" ) )
return 0
diff --git a/tools/bpf/bpftool/cgroup.c b/tools/bpf/bpftool/cgroup.c
index 73ec8ea33fb4..390b89a224f1 100644
--- a/tools/bpf/bpftool/cgroup.c
+++ b/tools/bpf/bpftool/cgroup.c
@@ -26,7 +26,8 @@
" sock_ops | device | bind4 | bind6 |\n" \
" post_bind4 | post_bind6 | connect4 |\n" \
" connect6 | sendmsg4 | sendmsg6 |\n" \
- " recvmsg4 | recvmsg6 | sysctl }"
+ " recvmsg4 | recvmsg6 | sysctl |\n" \
+ " getsockopt | setsockopt }"
static const char * const attach_type_strings[] = {
[BPF_CGROUP_INET_INGRESS] = "ingress",
@@ -45,6 +46,8 @@ static const char * const attach_type_strings[] = {
[BPF_CGROUP_SYSCTL] = "sysctl",
[BPF_CGROUP_UDP4_RECVMSG] = "recvmsg4",
[BPF_CGROUP_UDP6_RECVMSG] = "recvmsg6",
+ [BPF_CGROUP_GETSOCKOPT] = "getsockopt",
+ [BPF_CGROUP_SETSOCKOPT] = "setsockopt",
[__MAX_BPF_ATTACH_TYPE] = NULL,
};
diff --git a/tools/bpf/bpftool/main.h b/tools/bpf/bpftool/main.h
index 28a2a5857e14..9c5d9c80f71e 100644
--- a/tools/bpf/bpftool/main.h
+++ b/tools/bpf/bpftool/main.h
@@ -74,6 +74,7 @@ static const char * const prog_type_name[] = {
[BPF_PROG_TYPE_SK_REUSEPORT] = "sk_reuseport",
[BPF_PROG_TYPE_FLOW_DISSECTOR] = "flow_dissector",
[BPF_PROG_TYPE_CGROUP_SYSCTL] = "cgroup_sysctl",
+ [BPF_PROG_TYPE_CGROUP_SOCKOPT] = "cgroup_sockopt",
};
extern const char * const map_type_name[];
diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c
index f1a831f05010..9b0db5d14e31 100644
--- a/tools/bpf/bpftool/prog.c
+++ b/tools/bpf/bpftool/prog.c
@@ -1071,7 +1071,8 @@ static int do_help(int argc, char **argv)
" cgroup/bind4 | cgroup/bind6 | cgroup/post_bind4 |\n"
" cgroup/post_bind6 | cgroup/connect4 | cgroup/connect6 |\n"
" cgroup/sendmsg4 | cgroup/sendmsg6 | cgroup/recvmsg4 |\n"
- " cgroup/recvmsg6 }\n"
+ " cgroup/recvmsg6 | cgroup/getsockopt |\n"
+ " cgroup/setsockopt }\n"
" ATTACH_TYPE := { msg_verdict | stream_verdict | stream_parser |\n"
" flow_dissector }\n"
" " HELP_SPEC_OPTIONS "\n"
--
2.22.0.410.gd8fdbe21b5-goog
^ permalink raw reply related [flat|nested] 13+ messages in thread
* Re: [PATCH bpf-next v9 0/9] bpf: getsockopt and setsockopt hooks
2019-06-27 20:38 [PATCH bpf-next v9 0/9] bpf: getsockopt and setsockopt hooks Stanislav Fomichev
` (8 preceding siblings ...)
2019-06-27 20:38 ` [PATCH bpf-next v9 9/9] bpftool: support cgroup sockopt Stanislav Fomichev
@ 2019-06-27 22:31 ` Alexei Starovoitov
2019-06-27 22:43 ` Stanislav Fomichev
9 siblings, 1 reply; 13+ messages in thread
From: Alexei Starovoitov @ 2019-06-27 22:31 UTC (permalink / raw)
To: Stanislav Fomichev; +Cc: netdev, bpf, davem, ast, daniel
On Thu, Jun 27, 2019 at 01:38:46PM -0700, Stanislav Fomichev wrote:
> This series implements two new per-cgroup hooks: getsockopt and
> setsockopt along with a new sockopt program type. The idea is pretty
> similar to recently introduced cgroup sysctl hooks, but
> implementation is simpler (no need to convert to/from strings).
>
> What this can be applied to:
> * move business logic of what tos/priority/etc can be set by
> containers (either pass or reject)
> * handle existing options (or introduce new ones) differently by
> propagating some information in cgroup/socket local storage
>
> Compared to a simple syscall/{g,s}etsockopt tracepoint, those
> hooks are context aware. Meaning, they can access underlying socket
> and use cgroup and socket local storage.
>
> v9:
> * allow overwriting setsocktop arguments (Alexei Starovoitov)
> (see individual changes for more changelog details)
Applied. Thanks.
There is a build warning though:
test_sockopt_sk.c: In function ‘getsetsockopt’:
test_sockopt_sk.c:115:2: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing]
if (*(__u32 *)buf != 0x55AA*2) {
^~
test_sockopt_sk.c:116:3: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing]
log_err("Unexpected getsockopt(SO_SNDBUF) 0x%x != 0x55AA*2",
^~~~~~~
Pls fix it in the follow up.
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH bpf-next v9 0/9] bpf: getsockopt and setsockopt hooks
2019-06-27 22:31 ` [PATCH bpf-next v9 0/9] bpf: getsockopt and setsockopt hooks Alexei Starovoitov
@ 2019-06-27 22:43 ` Stanislav Fomichev
2019-06-27 22:46 ` Alexei Starovoitov
0 siblings, 1 reply; 13+ messages in thread
From: Stanislav Fomichev @ 2019-06-27 22:43 UTC (permalink / raw)
To: Alexei Starovoitov; +Cc: Stanislav Fomichev, netdev, bpf, davem, ast, daniel
On 06/27, Alexei Starovoitov wrote:
> On Thu, Jun 27, 2019 at 01:38:46PM -0700, Stanislav Fomichev wrote:
> > This series implements two new per-cgroup hooks: getsockopt and
> > setsockopt along with a new sockopt program type. The idea is pretty
> > similar to recently introduced cgroup sysctl hooks, but
> > implementation is simpler (no need to convert to/from strings).
> >
> > What this can be applied to:
> > * move business logic of what tos/priority/etc can be set by
> > containers (either pass or reject)
> > * handle existing options (or introduce new ones) differently by
> > propagating some information in cgroup/socket local storage
> >
> > Compared to a simple syscall/{g,s}etsockopt tracepoint, those
> > hooks are context aware. Meaning, they can access underlying socket
> > and use cgroup and socket local storage.
> >
> > v9:
> > * allow overwriting setsocktop arguments (Alexei Starovoitov)
> > (see individual changes for more changelog details)
>
> Applied. Thanks.
Great, thanks for all the reviews!
> There is a build warning though:
> test_sockopt_sk.c: In function ‘getsetsockopt’:
> test_sockopt_sk.c:115:2: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing]
> if (*(__u32 *)buf != 0x55AA*2) {
> ^~
> test_sockopt_sk.c:116:3: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing]
> log_err("Unexpected getsockopt(SO_SNDBUF) 0x%x != 0x55AA*2",
> ^~~~~~~
>
> Pls fix it in the follow up.
Sure, but I can't reproduce it with gcc7 nor with clang9 :-/
Presumably, a switch to __get_unaligned_cpu32 should help,
I'll try to play with compilers a bit before sending a fix.
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH bpf-next v9 0/9] bpf: getsockopt and setsockopt hooks
2019-06-27 22:43 ` Stanislav Fomichev
@ 2019-06-27 22:46 ` Alexei Starovoitov
0 siblings, 0 replies; 13+ messages in thread
From: Alexei Starovoitov @ 2019-06-27 22:46 UTC (permalink / raw)
To: Stanislav Fomichev
Cc: Stanislav Fomichev, Network Development, bpf, David S. Miller,
Alexei Starovoitov, Daniel Borkmann
On Thu, Jun 27, 2019 at 3:43 PM Stanislav Fomichev <sdf@fomichev.me> wrote:
>
> > There is a build warning though:
> > test_sockopt_sk.c: In function ‘getsetsockopt’:
> > test_sockopt_sk.c:115:2: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing]
> > if (*(__u32 *)buf != 0x55AA*2) {
> > ^~
> > test_sockopt_sk.c:116:3: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing]
> > log_err("Unexpected getsockopt(SO_SNDBUF) 0x%x != 0x55AA*2",
> > ^~~~~~~
> >
> > Pls fix it in the follow up.
> Sure, but I can't reproduce it with gcc7 nor with clang9 :-/
I see it with gcc 6.3
^ permalink raw reply [flat|nested] 13+ messages in thread
end of thread, other threads:[~2019-06-27 22:46 UTC | newest]
Thread overview: 13+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-06-27 20:38 [PATCH bpf-next v9 0/9] bpf: getsockopt and setsockopt hooks Stanislav Fomichev
2019-06-27 20:38 ` [PATCH bpf-next v9 1/9] bpf: implement " Stanislav Fomichev
2019-06-27 20:38 ` [PATCH bpf-next v9 2/9] bpf: sync bpf.h to tools/ Stanislav Fomichev
2019-06-27 20:38 ` [PATCH bpf-next v9 3/9] libbpf: support sockopt hooks Stanislav Fomichev
2019-06-27 20:38 ` [PATCH bpf-next v9 4/9] selftests/bpf: test sockopt section name Stanislav Fomichev
2019-06-27 20:38 ` [PATCH bpf-next v9 5/9] selftests/bpf: add sockopt test Stanislav Fomichev
2019-06-27 20:38 ` [PATCH bpf-next v9 6/9] selftests/bpf: add sockopt test that exercises sk helpers Stanislav Fomichev
2019-06-27 20:38 ` [PATCH bpf-next v9 7/9] selftests/bpf: add sockopt test that exercises BPF_F_ALLOW_MULTI Stanislav Fomichev
2019-06-27 20:38 ` [PATCH bpf-next v9 8/9] bpf: add sockopt documentation Stanislav Fomichev
2019-06-27 20:38 ` [PATCH bpf-next v9 9/9] bpftool: support cgroup sockopt Stanislav Fomichev
2019-06-27 22:31 ` [PATCH bpf-next v9 0/9] bpf: getsockopt and setsockopt hooks Alexei Starovoitov
2019-06-27 22:43 ` Stanislav Fomichev
2019-06-27 22:46 ` Alexei Starovoitov
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