From f28ea365cdefc3b4fd0373e70b0106a0cd9b4c23 Mon Sep 17 00:00:00 2001 From: Edward Jee Date: Thu, 8 Oct 2015 14:56:48 -0700 Subject: [PATCH] sock: support per-packet fwmark It's useful to allow users to set fwmark for an individual packet, without changing the socket state. The function this patch adds in sock layer can be used by the protocols that need such a feature. Signed-off-by: Edward Hyunkoo Jee Signed-off-by: Eric Dumazet Cc: Willem de Bruijn Signed-off-by: David S. Miller --- include/net/sock.h | 7 +++++++ net/core/sock.c | 26 ++++++++++++++++++++++++++ 2 files changed, 33 insertions(+) diff --git a/include/net/sock.h b/include/net/sock.h index 771ca1996442..9322cafd191b 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1514,6 +1514,13 @@ void sock_kfree_s(struct sock *sk, void *mem, int size); void sock_kzfree_s(struct sock *sk, void *mem, int size); void sk_send_sigurg(struct sock *sk); +struct sockcm_cookie { + u32 mark; +}; + +int sock_cmsg_send(struct sock *sk, struct msghdr *msg, + struct sockcm_cookie *sockc); + /* * Functions to fill in entries in struct proto_ops when a protocol * does not implement a particular function. diff --git a/net/core/sock.c b/net/core/sock.c index 7dd1263e4c24..33957776cc1a 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -1852,6 +1852,32 @@ struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, } EXPORT_SYMBOL(sock_alloc_send_skb); +int sock_cmsg_send(struct sock *sk, struct msghdr *msg, + struct sockcm_cookie *sockc) +{ + struct cmsghdr *cmsg; + + for_each_cmsghdr(cmsg, msg) { + if (!CMSG_OK(msg, cmsg)) + return -EINVAL; + if (cmsg->cmsg_level != SOL_SOCKET) + continue; + switch (cmsg->cmsg_type) { + case SO_MARK: + if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) + return -EPERM; + if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32))) + return -EINVAL; + sockc->mark = *(u32 *)CMSG_DATA(cmsg); + break; + default: + return -EINVAL; + } + } + return 0; +} +EXPORT_SYMBOL(sock_cmsg_send); + /* On 32bit arches, an skb frag is limited to 2^15 */ #define SKB_FRAG_PAGE_ORDER get_order(32768) -- 2.20.1