From 2c0dbaa0c43d04d8d6daf52adb724c5789676b15 Mon Sep 17 00:00:00 2001 From: Xin Long Date: Mon, 5 Mar 2018 20:44:19 +0800 Subject: [PATCH] sctp: add support for SCTP_DSTADDRV4/6 Information for sendmsg This patch is to add support for Destination IPv4/6 Address options for sendmsg, as described in section 5.3.9/10 of RFC6458. With this option, you can provide more than one destination addrs to sendmsg when creating asoc, like sctp_connectx. It's also a necessary send info for sctp_sendv. Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller --- include/net/sctp/structs.h | 1 + include/uapi/linux/sctp.h | 6 ++++ net/sctp/socket.c | 77 ++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 84 insertions(+) diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h index d40a2a329888..ec6e46b7e119 100644 --- a/include/net/sctp/structs.h +++ b/include/net/sctp/structs.h @@ -2113,6 +2113,7 @@ struct sctp_cmsgs { struct sctp_sndrcvinfo *srinfo; struct sctp_sndinfo *sinfo; struct sctp_prinfo *prinfo; + struct msghdr *addrs_msg; }; /* Structure for tracking memory objects */ diff --git a/include/uapi/linux/sctp.h b/include/uapi/linux/sctp.h index 0dd1f82a4fa8..a1bc35098033 100644 --- a/include/uapi/linux/sctp.h +++ b/include/uapi/linux/sctp.h @@ -308,6 +308,12 @@ typedef enum sctp_cmsg_type { #define SCTP_NXTINFO SCTP_NXTINFO SCTP_PRINFO, /* 5.3.7 SCTP PR-SCTP Information Structure */ #define SCTP_PRINFO SCTP_PRINFO + SCTP_AUTHINFO, /* 5.3.8 SCTP AUTH Information Structure (RESERVED) */ +#define SCTP_AUTHINFO SCTP_AUTHINFO + SCTP_DSTADDRV4, /* 5.3.9 SCTP Destination IPv4 Address Structure */ +#define SCTP_DSTADDRV4 SCTP_DSTADDRV4 + SCTP_DSTADDRV6, /* 5.3.10 SCTP Destination IPv6 Address Structure */ +#define SCTP_DSTADDRV6 SCTP_DSTADDRV6 } sctp_cmsg_t; /* diff --git a/net/sctp/socket.c b/net/sctp/socket.c index fdde697b37e7..067b57a330b1 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -1676,6 +1676,7 @@ static int sctp_sendmsg_new_asoc(struct sock *sk, __u16 sflags, struct net *net = sock_net(sk); struct sctp_association *asoc; enum sctp_scope scope; + struct cmsghdr *cmsg; int err = -EINVAL; *tp = NULL; @@ -1741,6 +1742,67 @@ static int sctp_sendmsg_new_asoc(struct sock *sk, __u16 sflags, goto free; } + if (!cmsgs->addrs_msg) + return 0; + + /* sendv addr list parse */ + for_each_cmsghdr(cmsg, cmsgs->addrs_msg) { + struct sctp_transport *transport; + struct sctp_association *old; + union sctp_addr _daddr; + int dlen; + + if (cmsg->cmsg_level != IPPROTO_SCTP || + (cmsg->cmsg_type != SCTP_DSTADDRV4 && + cmsg->cmsg_type != SCTP_DSTADDRV6)) + continue; + + daddr = &_daddr; + memset(daddr, 0, sizeof(*daddr)); + dlen = cmsg->cmsg_len - sizeof(struct cmsghdr); + if (cmsg->cmsg_type == SCTP_DSTADDRV4) { + if (dlen < sizeof(struct in_addr)) + goto free; + + dlen = sizeof(struct in_addr); + daddr->v4.sin_family = AF_INET; + daddr->v4.sin_port = htons(asoc->peer.port); + memcpy(&daddr->v4.sin_addr, CMSG_DATA(cmsg), dlen); + } else { + if (dlen < sizeof(struct in6_addr)) + goto free; + + dlen = sizeof(struct in6_addr); + daddr->v6.sin6_family = AF_INET6; + daddr->v6.sin6_port = htons(asoc->peer.port); + memcpy(&daddr->v6.sin6_addr, CMSG_DATA(cmsg), dlen); + } + err = sctp_verify_addr(sk, daddr, sizeof(*daddr)); + if (err) + goto free; + + old = sctp_endpoint_lookup_assoc(ep, daddr, &transport); + if (old && old != asoc) { + if (old->state >= SCTP_STATE_ESTABLISHED) + err = -EISCONN; + else + err = -EALREADY; + goto free; + } + + if (sctp_endpoint_is_peeled_off(ep, daddr)) { + err = -EADDRNOTAVAIL; + goto free; + } + + transport = sctp_assoc_add_peer(asoc, daddr, GFP_KERNEL, + SCTP_UNKNOWN); + if (!transport) { + err = -ENOMEM; + goto free; + } + } + return 0; free: @@ -7778,6 +7840,21 @@ static int sctp_msghdr_parse(const struct msghdr *msg, struct sctp_cmsgs *cmsgs) if (cmsgs->prinfo->pr_policy == SCTP_PR_SCTP_NONE) cmsgs->prinfo->pr_value = 0; break; + case SCTP_DSTADDRV4: + case SCTP_DSTADDRV6: + /* SCTP Socket API Extension + * 5.3.9/10 SCTP Destination IPv4/6 Address Structure (SCTP_DSTADDRV4/6) + * + * This cmsghdr structure specifies SCTP options for sendmsg(). + * + * cmsg_level cmsg_type cmsg_data[] + * ------------ ------------ --------------------- + * IPPROTO_SCTP SCTP_DSTADDRV4 struct in_addr + * ------------ ------------ --------------------- + * IPPROTO_SCTP SCTP_DSTADDRV6 struct in6_addr + */ + cmsgs->addrs_msg = my_msg; + break; default: return -EINVAL; } -- 2.11.0