From 0d3a421d284812d07970b4ccee74d4fa38737e4d Mon Sep 17 00:00:00 2001 From: Geir Ola Vaagland Date: Sat, 12 Jul 2014 20:30:37 +0200 Subject: [PATCH] net: sctp: implement rfc6458, 5.3.5. SCTP_RCVINFO cmsg support This patch implements section 5.3.5. of RFC6458, that is, support for 'SCTP Receive Information Structure' (SCTP_RCVINFO) which is placed into ancillary data cmsghdr structure for each recvmsg() call. This option can be enabled/disabled via setsockopt(2) on SOL_SCTP level by setting an int value with 1/0 for SCTP_RECVRCVINFO in user space applications as per RFC6458, section 8.1.29. The sctp_rcvinfo structure is defined as per RFC as below ... struct sctp_rcvinfo { uint16_t rcv_sid; uint16_t rcv_ssn; uint16_t rcv_flags; <-- 2 bytes hole --> uint32_t rcv_ppid; uint32_t rcv_tsn; uint32_t rcv_cumtsn; uint32_t rcv_context; sctp_assoc_t rcv_assoc_id; }; ... and provided under cmsg_level IPPROTO_SCTP, cmsg_type SCTP_RCVINFO, while cmsg_data[] contains struct sctp_rcvinfo. An sctp_rcvinfo item always corresponds to the data in msg_iov. Joint work with Daniel Borkmann. Signed-off-by: Geir Ola Vaagland Signed-off-by: Daniel Borkmann Signed-off-by: David S. Miller --- include/net/sctp/structs.h | 3 +++ include/net/sctp/ulpevent.h | 5 +++- include/uapi/linux/sctp.h | 32 ++++++++++++++++++------ net/sctp/socket.c | 49 ++++++++++++++++++++++++++++++++++++- net/sctp/ulpevent.c | 25 +++++++++++++++++++ 5 files changed, 105 insertions(+), 9 deletions(-) diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h index 7af9a0f5d8ce..11d5df015370 100644 --- a/include/net/sctp/structs.h +++ b/include/net/sctp/structs.h @@ -207,7 +207,9 @@ struct sctp_sock { struct sctp_paddrparams paddrparam; struct sctp_event_subscribe subscribe; struct sctp_assocparams assocparams; + int user_frag; + __u32 autoclose; __u8 nodelay; __u8 disable_fragments; @@ -215,6 +217,7 @@ struct sctp_sock { __u8 frag_interleave; __u32 adaptation_ind; __u32 pd_point; + __u8 recvrcvinfo; atomic_t pd_mode; /* Receive to here while partial delivery is in effect. */ diff --git a/include/net/sctp/ulpevent.h b/include/net/sctp/ulpevent.h index daacb32b55b5..e8095f973e94 100644 --- a/include/net/sctp/ulpevent.h +++ b/include/net/sctp/ulpevent.h @@ -129,7 +129,10 @@ struct sctp_ulpevent *sctp_ulpevent_make_sender_dry_event( const struct sctp_association *asoc, gfp_t gfp); void sctp_ulpevent_read_sndrcvinfo(const struct sctp_ulpevent *event, - struct msghdr *); + struct msghdr *); +void sctp_ulpevent_read_rcvinfo(const struct sctp_ulpevent *event, + struct msghdr *); + __u16 sctp_ulpevent_get_notification_type(const struct sctp_ulpevent *event); /* Is this event type enabled? */ diff --git a/include/uapi/linux/sctp.h b/include/uapi/linux/sctp.h index a387761f7e02..29b81bbfc53d 100644 --- a/include/uapi/linux/sctp.h +++ b/include/uapi/linux/sctp.h @@ -95,6 +95,7 @@ typedef __s32 sctp_assoc_t; #define SCTP_GET_ASSOC_ID_LIST 29 /* Read only */ #define SCTP_AUTO_ASCONF 30 #define SCTP_PEER_ADDR_THLDS 31 +#define SCTP_RECVRCVINFO 32 /* Internal Socket Options. Some of the sctp library functions are * implemented using these socket options. @@ -110,8 +111,7 @@ typedef __s32 sctp_assoc_t; #define SCTP_SOCKOPT_CONNECTX3 111 /* CONNECTX requests (updated) */ #define SCTP_GET_ASSOC_STATS 112 /* Read only */ -/* - * 5.2.1 SCTP Initiation Structure (SCTP_INIT) +/* 5.3.1 SCTP Initiation Structure (SCTP_INIT) * * This cmsghdr structure provides information for initializing new * SCTP associations with sendmsg(). The SCTP_INITMSG socket option @@ -121,7 +121,6 @@ typedef __s32 sctp_assoc_t; * cmsg_level cmsg_type cmsg_data[] * ------------ ------------ ---------------------- * IPPROTO_SCTP SCTP_INIT struct sctp_initmsg - * */ struct sctp_initmsg { __u16 sinit_num_ostreams; @@ -130,8 +129,7 @@ struct sctp_initmsg { __u16 sinit_max_init_timeo; }; -/* - * 5.2.2 SCTP Header Information Structure (SCTP_SNDRCV) +/* 5.3.2 SCTP Header Information Structure (SCTP_SNDRCV) * * This cmsghdr structure specifies SCTP options for sendmsg() and * describes SCTP header information about a received message through @@ -140,7 +138,6 @@ struct sctp_initmsg { * cmsg_level cmsg_type cmsg_data[] * ------------ ------------ ---------------------- * IPPROTO_SCTP SCTP_SNDRCV struct sctp_sndrcvinfo - * */ struct sctp_sndrcvinfo { __u16 sinfo_stream; @@ -170,13 +167,32 @@ struct sctp_sndinfo { sctp_assoc_t snd_assoc_id; }; +/* 5.3.5 SCTP Receive Information Structure (SCTP_RCVINFO) + * + * This cmsghdr structure describes SCTP receive information + * about a received message through recvmsg(). + * + * cmsg_level cmsg_type cmsg_data[] + * ------------ ------------ ------------------- + * IPPROTO_SCTP SCTP_RCVINFO struct sctp_rcvinfo + */ +struct sctp_rcvinfo { + __u16 rcv_sid; + __u16 rcv_ssn; + __u16 rcv_flags; + __u32 rcv_ppid; + __u32 rcv_tsn; + __u32 rcv_cumtsn; + __u32 rcv_context; + sctp_assoc_t rcv_assoc_id; +}; + /* * sinfo_flags: 16 bits (unsigned integer) * * This field may contain any of the following flags and is composed of * a bitwise OR of these values. */ - enum sctp_sinfo_flags { SCTP_UNORDERED = 1, /* Send/receive message unordered. */ SCTP_ADDR_OVER = 2, /* Override the primary destination. */ @@ -199,6 +215,8 @@ typedef enum sctp_cmsg_type { #define SCTP_SNDRCV SCTP_SNDRCV SCTP_SNDINFO, /* 5.3.4 SCTP Send Information Structure */ #define SCTP_SNDINFO SCTP_SNDINFO + SCTP_RCVINFO, /* 5.3.5 SCTP Receive Information Structure */ +#define SCTP_RCVINFO SCTP_RCVINFO } sctp_cmsg_t; /* diff --git a/net/sctp/socket.c b/net/sctp/socket.c index d61729e99856..9c193887c5cd 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -2112,9 +2112,13 @@ static int sctp_recvmsg(struct kiocb *iocb, struct sock *sk, sp->pf->skb_msgname(skb, msg->msg_name, addr_len); } + /* Check if we allow SCTP_RCVINFO. */ + if (sp->recvrcvinfo) + sctp_ulpevent_read_rcvinfo(event, msg); /* Check if we allow SCTP_SNDRCVINFO. */ if (sp->subscribe.sctp_data_io_event) sctp_ulpevent_read_sndrcvinfo(event, msg); + #if 0 /* FIXME: we should be calling IP/IPv6 layers. */ if (sk->sk_protinfo.af_inet.cmsg_flags) @@ -3541,7 +3545,6 @@ static int sctp_setsockopt_auto_asconf(struct sock *sk, char __user *optval, return 0; } - /* * SCTP_PEER_ADDR_THLDS * @@ -3592,6 +3595,22 @@ static int sctp_setsockopt_paddr_thresholds(struct sock *sk, return 0; } +static int sctp_setsockopt_recvrcvinfo(struct sock *sk, + char __user *optval, + unsigned int optlen) +{ + int val; + + if (optlen < sizeof(int)) + return -EINVAL; + if (get_user(val, (int __user *) optval)) + return -EFAULT; + + sctp_sk(sk)->recvrcvinfo = (val == 0) ? 0 : 1; + + return 0; +} + /* API 6.2 setsockopt(), getsockopt() * * Applications use setsockopt() and getsockopt() to set or retrieve @@ -3743,6 +3762,9 @@ static int sctp_setsockopt(struct sock *sk, int level, int optname, case SCTP_PEER_ADDR_THLDS: retval = sctp_setsockopt_paddr_thresholds(sk, optval, optlen); break; + case SCTP_RECVRCVINFO: + retval = sctp_setsockopt_recvrcvinfo(sk, optval, optlen); + break; default: retval = -ENOPROTOOPT; break; @@ -3989,6 +4011,8 @@ static int sctp_init_sock(struct sock *sk) /* Enable Nagle algorithm by default. */ sp->nodelay = 0; + sp->recvrcvinfo = 0; + /* Enable by default. */ sp->v4mapped = 1; @@ -5770,6 +5794,26 @@ static int sctp_getsockopt_assoc_stats(struct sock *sk, int len, return 0; } +static int sctp_getsockopt_recvrcvinfo(struct sock *sk, int len, + char __user *optval, + int __user *optlen) +{ + int val = 0; + + if (len < sizeof(int)) + return -EINVAL; + + len = sizeof(int); + if (sctp_sk(sk)->recvrcvinfo) + val = 1; + if (put_user(len, optlen)) + return -EFAULT; + if (copy_to_user(optval, &val, len)) + return -EFAULT; + + return 0; +} + static int sctp_getsockopt(struct sock *sk, int level, int optname, char __user *optval, int __user *optlen) { @@ -5913,6 +5957,9 @@ static int sctp_getsockopt(struct sock *sk, int level, int optname, case SCTP_GET_ASSOC_STATS: retval = sctp_getsockopt_assoc_stats(sk, len, optval, optlen); break; + case SCTP_RECVRCVINFO: + retval = sctp_getsockopt_recvrcvinfo(sk, len, optval, optlen); + break; default: retval = -ENOPROTOOPT; break; diff --git a/net/sctp/ulpevent.c b/net/sctp/ulpevent.c index b6842fdb53d4..b31f365f18ab 100644 --- a/net/sctp/ulpevent.c +++ b/net/sctp/ulpevent.c @@ -886,6 +886,31 @@ void sctp_ulpevent_read_sndrcvinfo(const struct sctp_ulpevent *event, sizeof(sinfo), &sinfo); } +/* RFC6458, Section 5.3.5 SCTP Receive Information Structure + * (SCTP_SNDRCV) + */ +void sctp_ulpevent_read_rcvinfo(const struct sctp_ulpevent *event, + struct msghdr *msghdr) +{ + struct sctp_rcvinfo rinfo; + + if (sctp_ulpevent_is_notification(event)) + return; + + memset(&rinfo, 0, sizeof(struct sctp_rcvinfo)); + rinfo.rcv_sid = event->stream; + rinfo.rcv_ssn = event->ssn; + rinfo.rcv_ppid = event->ppid; + rinfo.rcv_flags = event->flags; + rinfo.rcv_tsn = event->tsn; + rinfo.rcv_cumtsn = event->cumtsn; + rinfo.rcv_assoc_id = sctp_assoc2id(event->asoc); + rinfo.rcv_context = event->asoc->default_rcv_context; + + put_cmsg(msghdr, IPPROTO_SCTP, SCTP_RCVINFO, + sizeof(rinfo), &rinfo); +} + /* Do accounting for bytes received and hold a reference to the association * for each skb. */