From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chenbo Feng Subject: [PATCH net-next v5 1/3] Add a helper function to get socket cookie in eBPF Date: Mon, 20 Mar 2017 11:41:04 -0700 Message-ID: <1490035266-9861-2-git-send-email-chenbofeng.kernel@gmail.com> References: <1490035266-9861-1-git-send-email-chenbofeng.kernel@gmail.com> Cc: Lorenzo Colitti , Willem de Bruijn , Chenbo Feng To: netdev@vger.kernel.org, Alexei Starovoitov , Daniel Borkmann Return-path: Received: from mail-pg0-f68.google.com ([74.125.83.68]:32873 "EHLO mail-pg0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755916AbdCTSlw (ORCPT ); Mon, 20 Mar 2017 14:41:52 -0400 Received: by mail-pg0-f68.google.com with SMTP id 79so12709596pgf.0 for ; Mon, 20 Mar 2017 11:41:23 -0700 (PDT) In-Reply-To: <1490035266-9861-1-git-send-email-chenbofeng.kernel@gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Chenbo Feng Retrieve the socket cookie generated by sock_gen_cookie() from a sk_buff with a known socket. Generates a new cookie if one was not yet set.If the socket pointer inside sk_buff is NULL, 0 is returned. The helper function coud be useful in monitoring per socket networking traffic statistics and provide a unique socket identifier per namespace. Signed-off-by: Chenbo Feng --- include/linux/sock_diag.h | 1 + include/uapi/linux/bpf.h | 9 ++++++++- net/core/filter.c | 17 +++++++++++++++++ net/core/sock_diag.c | 2 +- tools/include/uapi/linux/bpf.h | 3 ++- 5 files changed, 29 insertions(+), 3 deletions(-) diff --git a/include/linux/sock_diag.h b/include/linux/sock_diag.h index a0596ca0..a2f8109 100644 --- a/include/linux/sock_diag.h +++ b/include/linux/sock_diag.h @@ -24,6 +24,7 @@ void sock_diag_unregister(const struct sock_diag_handler *h); void sock_diag_register_inet_compat(int (*fn)(struct sk_buff *skb, struct nlmsghdr *nlh)); void sock_diag_unregister_inet_compat(int (*fn)(struct sk_buff *skb, struct nlmsghdr *nlh)); +u64 sock_gen_cookie(struct sock *sk); int sock_diag_check_cookie(struct sock *sk, const __u32 *cookie); void sock_diag_save_cookie(struct sock *sk, __u32 *cookie); diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 0539a0c..dc81a9f 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -456,6 +456,12 @@ union bpf_attr { * Return: * > 0 length of the string including the trailing NUL on success * < 0 error + * + * u64 bpf_bpf_get_socket_cookie(skb) + * Get the cookie for the socket stored inside sk_buff. + * @skb: pointer to skb + * Return: 8 Bytes non-decreasing number on success or 0 if the socket + * field is missing inside sk_buff */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -503,7 +509,8 @@ union bpf_attr { FN(get_numa_node_id), \ FN(skb_change_head), \ FN(xdp_adjust_head), \ - FN(probe_read_str), + FN(probe_read_str), \ + FN(get_socket_cookie), /* 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 ebaeaf2..5b65ae3 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -26,6 +26,7 @@ #include #include #include +#include #include #include #include @@ -2599,6 +2600,18 @@ static const struct bpf_func_proto bpf_xdp_event_output_proto = { .arg5_type = ARG_CONST_SIZE, }; +BPF_CALL_1(bpf_get_socket_cookie, struct sk_buff *, skb) +{ + return skb->sk ? sock_gen_cookie(skb->sk) : 0; +} + +static const struct bpf_func_proto bpf_get_socket_cookie_proto = { + .func = bpf_get_socket_cookie, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_CTX, +}; + static const struct bpf_func_proto * bpf_base_func_proto(enum bpf_func_id func_id) { @@ -2633,6 +2646,8 @@ sk_filter_func_proto(enum bpf_func_id func_id) switch (func_id) { case BPF_FUNC_skb_load_bytes: return &bpf_skb_load_bytes_proto; + case BPF_FUNC_get_socket_cookie: + return &bpf_get_socket_cookie_proto; default: return bpf_base_func_proto(func_id); } @@ -2692,6 +2707,8 @@ tc_cls_act_func_proto(enum bpf_func_id func_id) return &bpf_get_smp_processor_id_proto; case BPF_FUNC_skb_under_cgroup: return &bpf_skb_under_cgroup_proto; + case BPF_FUNC_get_socket_cookie: + return &bpf_get_socket_cookie_proto; default: return bpf_base_func_proto(func_id); } diff --git a/net/core/sock_diag.c b/net/core/sock_diag.c index 6b10573..acd2a6c 100644 --- a/net/core/sock_diag.c +++ b/net/core/sock_diag.c @@ -19,7 +19,7 @@ static int (*inet_rcv_compat)(struct sk_buff *skb, struct nlmsghdr *nlh); static DEFINE_MUTEX(sock_diag_table_mutex); static struct workqueue_struct *broadcast_wq; -static u64 sock_gen_cookie(struct sock *sk) +u64 sock_gen_cookie(struct sock *sk) { while (1) { u64 res = atomic64_read(&sk->sk_cookie); diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 0539a0c..a94bdd3 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -503,7 +503,8 @@ union bpf_attr { FN(get_numa_node_id), \ FN(skb_change_head), \ FN(xdp_adjust_head), \ - FN(probe_read_str), + FN(probe_read_str), \ + FN(get_socket_cookie), /* integer value in 'imm' field of BPF_CALL instruction selects which helper * function eBPF program intends to call -- 2.7.4