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)