1 /* SCTP kernel Implementation: User API extensions. 2 * 3 * sendmsg.c 4 * 5 * Distributed under the terms of the LGPL v2.1 as described in 6 * http://www.gnu.org/copyleft/lesser.txt 7 * 8 * This file is part of the user library that offers support for the 9 * SCTP kernel Implementation. The main purpose of this 10 * code is to provide the SCTP Socket API mappings for user 11 * application to interface with the SCTP in kernel. 12 * 13 * This implementation is based on the Socket API Extensions for SCTP 14 * defined in <draft-ietf-tsvwg-sctpsocket-10.txt> 15 * 16 * Copyright (c) 2003 Intel Corp. 17 * 18 * Written or modified by: 19 * Ardelle Fan <ardelle.fan (at) intel.com> 20 */ 21 22 #include <string.h> 23 #include <sys/socket.h> /* struct sockaddr_storage, setsockopt() */ 24 #include <netinet/sctp.h> 25 26 /* This library function assists the user with the advanced features 27 * of SCTP. This is a new SCTP API described in the section 8.7 of the 28 * Sockets API Extensions for SCTP. This is implemented using the 29 * sendmsg() interface. 30 */ 31 int 32 sctp_sendmsg(int s, const void *msg, size_t len, struct sockaddr *to, 33 socklen_t tolen, uint32_t ppid, uint32_t flags, 34 uint16_t stream_no, uint32_t timetolive, uint32_t context) 35 { 36 struct msghdr outmsg; 37 struct iovec iov; 38 char outcmsg[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))]; 39 struct cmsghdr *cmsg; 40 struct sctp_sndrcvinfo *sinfo; 41 42 outmsg.msg_name = to; 43 outmsg.msg_namelen = tolen; 44 outmsg.msg_iov = &iov; 45 iov.iov_base = (void *)msg; 46 iov.iov_len = len; 47 outmsg.msg_iovlen = 1; 48 49 outmsg.msg_control = outcmsg; 50 outmsg.msg_controllen = sizeof(outcmsg); 51 outmsg.msg_flags = 0; 52 53 cmsg = CMSG_FIRSTHDR(&outmsg); 54 cmsg->cmsg_level = IPPROTO_SCTP; 55 cmsg->cmsg_type = SCTP_SNDRCV; 56 cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_sndrcvinfo)); 57 58 outmsg.msg_controllen = cmsg->cmsg_len; 59 sinfo = (struct sctp_sndrcvinfo *)CMSG_DATA(cmsg); 60 memset(sinfo, 0, sizeof(struct sctp_sndrcvinfo)); 61 sinfo->sinfo_ppid = ppid; 62 sinfo->sinfo_flags = flags; 63 sinfo->sinfo_stream = stream_no; 64 sinfo->sinfo_timetolive = timetolive; 65 sinfo->sinfo_context = context; 66 67 return sendmsg(s, &outmsg, 0); 68 } 69 70 /* This library function assist the user with sending a message without 71 * dealing directly with the CMSG header. 72 */ 73 int 74 sctp_send(int s, const void *msg, size_t len, 75 const struct sctp_sndrcvinfo *sinfo, int flags) 76 { 77 struct msghdr outmsg; 78 struct iovec iov; 79 char outcmsg[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))]; 80 81 outmsg.msg_name = NULL; 82 outmsg.msg_namelen = 0; 83 outmsg.msg_iov = &iov; 84 iov.iov_base = (void *)msg; 85 iov.iov_len = len; 86 outmsg.msg_iovlen = 1; 87 outmsg.msg_controllen = 0; 88 89 if (sinfo) { 90 struct cmsghdr *cmsg; 91 92 outmsg.msg_control = outcmsg; 93 outmsg.msg_controllen = sizeof(outcmsg); 94 outmsg.msg_flags = 0; 95 96 cmsg = CMSG_FIRSTHDR(&outmsg); 97 cmsg->cmsg_level = IPPROTO_SCTP; 98 cmsg->cmsg_type = SCTP_SNDRCV; 99 cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_sndrcvinfo)); 100 101 outmsg.msg_controllen = cmsg->cmsg_len; 102 memcpy(CMSG_DATA(cmsg), sinfo, sizeof(struct sctp_sndrcvinfo)); 103 } 104 105 return sendmsg(s, &outmsg, flags); 106 } 107