From: Lawrence Brakmo <brakmo@fb•com>
To: netdev <netdev@vger•kernel.org>
Cc: Kernel Team <kernel-team@fb•com>, Alexei Starovoitov <ast@fb•com>,
"Daniel Borkmann" <daniel@iogearbox•net>,
Blake Matheny <bmatheny@fb•com>,
"Lawrence Brakmo" <brakmo@fb•com>
Subject: [PATCH net-next 2/5] bpf: Adding helper function bpf_getsockops
Date: Fri, 20 Oct 2017 11:05:40 -0700 [thread overview]
Message-ID: <20171020180543.4156833-3-brakmo@fb.com> (raw)
In-Reply-To: <20171020180543.4156833-1-brakmo@fb.com>
Adding support for helper function bpf_getsockops to socket_ops BPF
programs. This patch only supports TCP_CONGESTION.
Signed-off-by: Vlad Vysotsky <vlad@cs•ucla.edu>
Acked-by: Lawrence Brakmo <brakmo@fb•com>
Acked-by: Alexei Starovoitov <ast@fb•com>
Acked-by: Daniel Borkmann <daniel@iogearbox•net>
---
include/uapi/linux/bpf.h | 19 ++++++++++---
net/core/filter.c | 46 ++++++++++++++++++++++++++++++-
tools/testing/selftests/bpf/bpf_helpers.h | 3 ++
3 files changed, 63 insertions(+), 5 deletions(-)
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 1aca744..f650346 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -613,12 +613,22 @@ union bpf_attr {
* int bpf_setsockopt(bpf_socket, level, optname, optval, optlen)
* Calls setsockopt. Not all opts are available, only those with
* integer optvals plus TCP_CONGESTION.
- * Supported levels: SOL_SOCKET and IPROTO_TCP
+ * Supported levels: SOL_SOCKET and IPPROTO_TCP
* @bpf_socket: pointer to bpf_socket
- * @level: SOL_SOCKET or IPROTO_TCP
+ * @level: SOL_SOCKET or IPPROTO_TCP
* @optname: option name
* @optval: pointer to option value
- * @optlen: length of optval in byes
+ * @optlen: length of optval in bytes
+ * Return: 0 or negative error
+ *
+ * int bpf_getsockopt(bpf_socket, level, optname, optval, optlen)
+ * Calls getsockopt. Not all opts are available.
+ * Supported levels: IPPROTO_TCP
+ * @bpf_socket: pointer to bpf_socket
+ * @level: IPPROTO_TCP
+ * @optname: option name
+ * @optval: pointer to option value
+ * @optlen: length of optval in bytes
* Return: 0 or negative error
*
* int bpf_skb_adjust_room(skb, len_diff, mode, flags)
@@ -721,7 +731,8 @@ union bpf_attr {
FN(sock_map_update), \
FN(xdp_adjust_meta), \
FN(perf_event_read_value), \
- FN(perf_prog_read_value),
+ FN(perf_prog_read_value), \
+ FN(getsockopt),
/* integer value in 'imm' field of BPF_CALL instruction selects which helper
* function eBPF program intends to call
diff --git a/net/core/filter.c b/net/core/filter.c
index 09e011f..ccf62f4 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -3273,7 +3273,7 @@ BPF_CALL_5(bpf_setsockopt, struct bpf_sock_ops_kern *, bpf_sock,
static const struct bpf_func_proto bpf_setsockopt_proto = {
.func = bpf_setsockopt,
- .gpl_only = true,
+ .gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
@@ -3282,6 +3282,48 @@ static const struct bpf_func_proto bpf_setsockopt_proto = {
.arg5_type = ARG_CONST_SIZE,
};
+BPF_CALL_5(bpf_getsockopt, struct bpf_sock_ops_kern *, bpf_sock,
+ int, level, int, optname, char *, optval, int, optlen)
+{
+ struct sock *sk = bpf_sock->sk;
+ int ret = 0;
+
+ if (!sk_fullsock(sk))
+ goto err_clear;
+
+#ifdef CONFIG_INET
+ if (level == SOL_TCP && sk->sk_prot->getsockopt == tcp_getsockopt) {
+ if (optname == TCP_CONGESTION) {
+ struct inet_connection_sock *icsk = inet_csk(sk);
+
+ if (!icsk->icsk_ca_ops || optlen <= 1)
+ goto err_clear;
+ strncpy(optval, icsk->icsk_ca_ops->name, optlen);
+ optval[optlen - 1] = 0;
+ } else {
+ goto err_clear;
+ }
+ } else {
+ goto err_clear;
+ }
+ return ret;
+#endif
+err_clear:
+ memset(optval, 0, optlen);
+ return -EINVAL;
+}
+
+static const struct bpf_func_proto bpf_getsockopt_proto = {
+ .func = bpf_getsockopt,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_ANYTHING,
+ .arg3_type = ARG_ANYTHING,
+ .arg4_type = ARG_PTR_TO_UNINIT_MEM,
+ .arg5_type = ARG_CONST_SIZE,
+};
+
static const struct bpf_func_proto *
bpf_base_func_proto(enum bpf_func_id func_id)
{
@@ -3460,6 +3502,8 @@ static const struct bpf_func_proto *
switch (func_id) {
case BPF_FUNC_setsockopt:
return &bpf_setsockopt_proto;
+ case BPF_FUNC_getsockopt:
+ return &bpf_getsockopt_proto;
case BPF_FUNC_sock_map_update:
return &bpf_sock_map_update_proto;
default:
diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h
index e25dbf6..609514f 100644
--- a/tools/testing/selftests/bpf/bpf_helpers.h
+++ b/tools/testing/selftests/bpf/bpf_helpers.h
@@ -67,6 +67,9 @@ static int (*bpf_xdp_adjust_meta)(void *ctx, int offset) =
static int (*bpf_setsockopt)(void *ctx, int level, int optname, void *optval,
int optlen) =
(void *) BPF_FUNC_setsockopt;
+static int (*bpf_getsockopt)(void *ctx, int level, int optname, void *optval,
+ int optlen) =
+ (void *) BPF_FUNC_getsockopt;
static int (*bpf_sk_redirect_map)(void *map, int key, int flags) =
(void *) BPF_FUNC_sk_redirect_map;
static int (*bpf_sock_map_update)(void *map, void *key, void *value,
--
2.9.5
next prev parent reply other threads:[~2017-10-20 18:06 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-10-20 18:05 [PATCH net-next 0/5] bpf: add support for BASE_RTT Lawrence Brakmo
2017-10-20 18:05 ` [PATCH net-next 1/5] bpf: add support for BPF_SOCK_OPS_BASE_RTT Lawrence Brakmo
2017-10-20 18:05 ` Lawrence Brakmo [this message]
2017-10-20 18:05 ` [PATCH net-next 3/5] bpf: Add BPF_SOCKET_OPS_BASE_RTT support to tcp_nv Lawrence Brakmo
2017-10-21 19:37 ` Alexei Starovoitov
2017-10-20 18:05 ` [PATCH net-next 4/5] bpf: sample BPF_SOCKET_OPS_BASE_RTT program Lawrence Brakmo
2017-10-20 18:05 ` [PATCH net-next 5/5] bpf: create samples/bpf/tcp_bpf.readme Lawrence Brakmo
2017-10-22 2:12 ` [PATCH net-next 0/5] bpf: add support for BASE_RTT David Miller
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