/* -*- Mode: C; tab-width: 4 -*- * * Copyright (c) 2002-2004 Apple Computer, Inc. All rights reserved. * * @APPLE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this * file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_LICENSE_HEADER_END@ Change History (most recent first): $Log: mDNSUNP.c,v $ Revision 1.30 2005/11/29 20:03:02 mkrochma Wrapped sin_len with #ifndef NOT_HAVE_SA_LEN Revision 1.29 2005/11/12 02:23:10 cheshire mDNSUNP.c needs to deal with lame results from SIOCGIFNETMASK, SIOCGIFBRDADDR and SIOCGIFDSTADDR Revision 1.28 2005/10/31 22:09:45 cheshire Buffer "char addr6[33]" was seven bytes too small Revision 1.27 2005/06/29 15:54:21 cheshire mDNSResponder-107.1 does not work on FreeBSD Refine last checkin so that it (hopefully) doesn't break get_ifi_info() for every other OS Revision 1.26 2005/04/08 21:43:59 ksekar mDNSPosix (v98) retrieve interface list bug on AMD64 architecture Submitted by Andrew de Quincey Revision 1.25 2005/04/08 21:37:57 ksekar get_ifi_info doesn't return IPv6 interfaces on Linux Revision 1.24 2005/04/08 21:30:16 ksekar Compiling problems with mDNSResponder-98 on Solaris/Sparc v9 Patch submitted by Bernd Kuhls Revision 1.23 2004/12/01 04:25:05 cheshire Darwin patches for Solaris and Suse Provide daemon() for platforms that don't have it Revision 1.22 2004/11/30 22:37:01 cheshire Update copyright dates and add "Mode: C; tab-width: 4" headers Revision 1.21 2004/11/08 22:13:59 rpantos Create sockf6 lazily when v6 interface found. Revision 1.20 2004/10/16 00:17:01 cheshire Replace IP TTL 255 check with local subnet source address check Revision 1.19 2004/07/20 01:47:36 rpantos NOT_HAVE_SA_LEN applies to v6, too. And use more-portable s6_addr. Revision 1.18 2004/07/08 21:30:21 rpantos Revision 1.17 2004/06/25 00:26:27 rpantos Changes to fix the Posix build on Solaris. Revision 1.16 2004/03/20 05:37:09 cheshire Fix contributed by Terry Lambert & Alfred Perlstein: Don't use uint8_t -- it requires stdint.h, which doesn't exist on FreeBSD 4.x Revision 1.15 2004/02/14 01:09:45 rpantos Just use HAVE_IPV6 rather than defined(HAVE_IPV6). Revision 1.14 2003/12/11 18:53:40 cheshire Fix compiler warning reported by Paul Guyot Revision 1.13 2003/12/08 20:47:02 rpantos Add support for mDNSResponder on Linux. Revision 1.12 2003/09/02 20:47:13 cheshire Fix signed/unsigned warning Revision 1.11 2003/08/12 19:56:26 cheshire Update to APSL 2.0 Revision 1.10 2003/08/06 18:20:51 cheshire Makefile cleanup Revision 1.9 2003/07/14 18:11:54 cheshire Fix stricter compiler warnings Revision 1.8 2003/07/02 21:19:59 cheshire Update copyright notices, etc., in source code comments Revision 1.7 2003/03/20 21:10:31 cheshire Fixes done at IETF 56 to make mDNSProxyResponderPosix run on Solaris Revision 1.6 2003/03/13 03:46:21 cheshire Fixes to make the code build on Linux Revision 1.5 2003/02/07 03:02:02 cheshire Submitted by: Mitsutaka Watanabe The code saying "index += 1;" was effectively making up random interface index values. The right way to find the correct interface index is if_nametoindex(); Revision 1.4 2002/12/23 22:13:31 jgraessl Reviewed by: Stuart Cheshire Initial IPv6 support for mDNSResponder. Revision 1.3 2002/09/21 20:44:53 zarzycki Added APSL info Revision 1.2 2002/09/19 04:20:44 cheshire Remove high-ascii characters that confuse some systems Revision 1.1 2002/09/17 06:24:34 cheshire First checkin */ #include "mDNSUNP.h" #include #include #include #include #include #include #include #include /* Solaris defined SIOCGIFCONF etc in but other platforms don't even have that include file. So, if we haven't yet got a definition, let's try to find . */ #ifndef SIOCGIFCONF #include #endif /* sockaddr_dl is only referenced if we're using IP_RECVIF, so only include the header in that case. */ #ifdef IP_RECVIF #include #endif #if defined(AF_INET6) && HAVE_IPV6 && !HAVE_LINUX #include #endif #if defined(AF_INET6) && HAVE_IPV6 && HAVE_LINUX #include #include /* Converts a prefix length to IPv6 network mask */ void plen_to_mask(int plen, char *addr) { int i; int colons=7; /* Number of colons in IPv6 address */ int bits_in_block=16; /* Bits per IPv6 block */ for(i=0;i<=colons;i++) { int block, ones=0xffff, ones_in_block; if(plen>bits_in_block) ones_in_block=bits_in_block; else ones_in_block=plen; block = ones & (ones << (bits_in_block-ones_in_block)); i==0 ? sprintf(addr, "%x", block) : sprintf(addr, "%s:%x", addr, block); plen -= ones_in_block; } } /* Gets IPv6 interface information from the /proc filesystem in linux*/ struct ifi_info *get_ifi_info_linuxv6(int family, int doaliases) { struct ifi_info *ifi, *ifihead, **ifipnext; FILE *fp; char addr[8][5]; int flags, myflags, index, plen, scope; char ifname[8], lastname[IFNAMSIZ]; char addr6[32+7+1]; /* don't forget the seven ':' */ struct addrinfo hints, *res0; struct sockaddr_in6 *sin6; struct in6_addr *addrptr; int err; res0=NULL; ifihead = NULL; ifipnext = &ifihead; lastname[0] = 0; if ((fp = fopen(PROC_IFINET6_PATH, "r")) != NULL) { while (fscanf(fp, "%4s%4s%4s%4s%4s%4s%4s%4s %02x %02x %02x %02x %8s\n", addr[0],addr[1],addr[2],addr[3], addr[4],addr[5],addr[6],addr[7], &index, &plen, &scope, &flags, ifname) != EOF) { myflags = 0; if (strncmp(lastname, ifname, IFNAMSIZ) == 0) { if (doaliases == 0) continue; /* already processed this interface */ myflags = IFI_ALIAS; } memcpy(lastname, ifname, IFNAMSIZ); ifi = (struct ifi_info*)calloc(1, sizeof(struct ifi_info)); if (ifi == NULL) { goto gotError; } *ifipnext = ifi; /* prev points to this new one */ ifipnext = &ifi->ifi_next; /* pointer to next one goes here */ sprintf(addr6, "%s:%s:%s:%s:%s:%s:%s:%s", addr[0],addr[1],addr[2],addr[3], addr[4],addr[5],addr[6],addr[7]); /* Add address of the interface */ memset(&hints, 0, sizeof(hints)); hints.ai_family = AF_INET6; hints.ai_flags = AI_NUMERICHOST; err = getaddrinfo(addr6, NULL, &hints, &res0); if (err) { goto gotError; } ifi->ifi_addr = calloc(1, sizeof(struct sockaddr_in6)); if (ifi->ifi_addr == NULL) { goto gotError; } memcpy(ifi->ifi_addr, res0->ai_addr, sizeof(struct sockaddr_in6)); /* Add netmask of the interface */ char ipv6addr[INET6_ADDRSTRLEN]; plen_to_mask(plen, ipv6addr); ifi->ifi_netmask = calloc(1, sizeof(struct sockaddr_in6)); if (ifi->ifi_addr == NULL) { goto gotError; } sin6=calloc(1, sizeof(struct sockaddr_in6)); addrptr=calloc(1, sizeof(struct in6_addr)); inet_pton(family, ipv6addr, addrptr); sin6->sin6_family=family; sin6->sin6_addr=*addrptr; sin6->sin6_scope_id=scope; memcpy(ifi->ifi_netmask, sin6, sizeof(struct sockaddr_in6)); free(sin6); /* Add interface name */ memcpy(ifi->ifi_name, ifname, IFI_NAME); /* Add interface index */ ifi->ifi_index = index; /* If interface is in /proc then it is up*/ ifi->ifi_flags = IFF_UP; freeaddrinfo(res0); res0=NULL; } } goto done; gotError: if (ifihead != NULL) { free_ifi_info(ifihead); ifihead = NULL; } if (res0 != NULL) { freeaddrinfo(res0); res0=NULL; } done: return(ifihead); /* pointer to first structure in linked list */ } #endif // defined(AF_INET6) && HAVE_IPV6 && HAVE_LINUX struct ifi_info *get_ifi_info(int family, int doaliases) { int junk; struct ifi_info *ifi, *ifihead, **ifipnext; int sockfd, sockf6, len, lastlen, flags, myflags; #ifdef NOT_HAVE_IF_NAMETOINDEX int index = 200; #endif char *ptr, *buf, lastname[IFNAMSIZ], *cptr; struct ifconf ifc; struct ifreq *ifr, ifrcopy; struct sockaddr_in *sinptr; #if defined(AF_INET6) && HAVE_IPV6 struct sockaddr_in6 *sinptr6; #endif #if defined(AF_INET6) && HAVE_IPV6 && HAVE_LINUX if(family == AF_INET6) return get_ifi_info_linuxv6(family, doaliases); #endif sockfd = -1; sockf6 = -1; buf = NULL; ifihead = NULL; sockfd = socket(AF_INET, SOCK_DGRAM, 0); if (sockfd < 0) { goto gotError; } lastlen = 0; len = 100 * sizeof(struct ifreq); /* initial buffer size guess */ for ( ; ; ) { buf = (char*)malloc(len); if (buf == NULL) { goto gotError; } ifc.ifc_len = len; ifc.ifc_buf = buf; if (ioctl(sockfd, SIOCGIFCONF, &ifc) < 0) { if (errno != EINVAL || lastlen != 0) { goto gotError; } } else { if (ifc.ifc_len == lastlen) break; /* success, len has not changed */ lastlen = ifc.ifc_len; } len += 10 * sizeof(struct ifreq); /* increment */ free(buf); } ifihead = NULL; ifipnext = &ifihead; lastname[0] = 0; /* end get_ifi_info1 */ /* include get_ifi_info2 */ for (ptr = buf; ptr < buf + ifc.ifc_len; ) { ifr = (struct ifreq *) ptr; /* Advance to next one in buffer */ if (sizeof(struct ifreq) > sizeof(ifr->ifr_name) + GET_SA_LEN(ifr->ifr_addr)) ptr += sizeof(struct ifreq); else ptr += sizeof(ifr->ifr_name) + GET_SA_LEN(ifr->ifr_addr); // fprintf(stderr, "intf %p name=%s AF=%d\n", index, ifr->ifr_name, ifr->ifr_addr.sa_family); if (ifr->ifr_addr.sa_family != family) continue; /* ignore if not desired address family */ myflags = 0; if ( (cptr = strchr(ifr->ifr_name, ':')) != NULL) *cptr = 0; /* replace colon will null */ if (strncmp(lastname, ifr->ifr_name, IFNAMSIZ) == 0) { if (doaliases == 0) continue; /* already processed this interface */ myflags = IFI_ALIAS; } memcpy(lastname, ifr->ifr_name, IFNAMSIZ); ifrcopy = *ifr; if (ioctl(sockfd, SIOCGIFFLAGS, &ifrcopy) < 0) { goto gotError; } flags = ifrcopy.ifr_flags; if ((flags & IFF_UP) == 0) continue; /* ignore if interface not up */ ifi = (struct ifi_info*)calloc(1, sizeof(struct ifi_info)); if (ifi == NULL) { goto gotError; } *ifipnext = ifi; /* prev points to this new one */ ifipnext = &ifi->ifi_next; /* pointer to next one goes here */ ifi->ifi_flags = flags; /* IFF_xxx values */ ifi->ifi_myflags = myflags; /* IFI_xxx values */ #ifndef NOT_HAVE_IF_NAMETOINDEX ifi->ifi_index = if_nametoindex(ifr->ifr_name); #else ifrcopy = *ifr; if ( 0 >= ioctl(sockfd, SIOCGIFINDEX, &ifrcopy)) ifi->ifi_index = ifrcopy.ifr_index; else ifi->ifi_index = index++; /* SIOCGIFINDEX is broken on Solaris 2.5ish, so fake it */ #endif memcpy(ifi->ifi_name, ifr->ifr_name, IFI_NAME); ifi->ifi_name[IFI_NAME-1] = '\0'; /* end get_ifi_info2 */ /* include get_ifi_info3 */ switch (ifr->ifr_addr.sa_family) { case AF_INET: sinptr = (struct sockaddr_in *) &ifr->ifr_addr; if (ifi->ifi_addr == NULL) { ifi->ifi_addr = (struct sockaddr*)calloc(1, sizeof(struct sockaddr_in)); if (ifi->ifi_addr == NULL) { goto gotError; } memcpy(ifi->ifi_addr, sinptr, sizeof(struct sockaddr_in)); #ifdef SIOCGIFNETMASK if (ioctl(sockfd, SIOCGIFNETMASK, &ifrcopy) < 0) goto gotError; ifi->ifi_netmask = (struct sockaddr*)calloc(1, sizeof(struct sockaddr_in)); if (ifi->ifi_netmask == NULL) goto gotError; sinptr = (struct sockaddr_in *) &ifrcopy.ifr_addr; /* The BSD ioctls (including Mac OS X) stick some weird values in for sin_len and sin_family */ #ifndef NOT_HAVE_SA_LEN sinptr->sin_len = sizeof(struct sockaddr_in); #endif sinptr->sin_family = AF_INET; memcpy(ifi->ifi_netmask, sinptr, sizeof(struct sockaddr_in)); #endif #ifdef SIOCGIFBRDADDR if (flags & IFF_BROADCAST) { if (ioctl(sockfd, SIOCGIFBRDADDR, &ifrcopy) < 0) { goto gotError; } sinptr = (struct sockaddr_in *) &ifrcopy.ifr_broadaddr; /* The BSD ioctls (including Mac OS X) stick some weird values in for sin_len and sin_family */ #ifndef NOT_HAVE_SA_LEN sinptr->sin_len = sizeof( struct sockaddr_in ); #endif sinptr->sin_family = AF_INET; ifi->ifi_brdaddr = (struct sockaddr*)calloc(1, sizeof(struct sockaddr_in)); if (ifi->ifi_brdaddr == NULL) { goto gotError; } memcpy(ifi->ifi_brdaddr, sinptr, sizeof(struct sockaddr_in)); } #endif #ifdef SIOCGIFDSTADDR if (flags & IFF_POINTOPOINT) { if (ioctl(sockfd, SIOCGIFDSTADDR, &ifrcopy) < 0) { goto gotError; } sinptr = (struct sockaddr_in *) &ifrcopy.ifr_dstaddr; /* The BSD ioctls (including Mac OS X) stick some weird values in for sin_len and sin_family */ #ifndef NOT_HAVE_SA_LEN sinptr->sin_len = sizeof( struct sockaddr_in ); #endif sinptr->sin_family = AF_INET; ifi->ifi_dstaddr = (struct sockaddr*)calloc(1, sizeof(struct sockaddr_in)); if (ifi->ifi_dstaddr == NULL) { goto gotError; } memcpy(ifi->ifi_dstaddr, sinptr, sizeof(struct sockaddr_in)); } #endif } break; #if defined(AF_INET6) && HAVE_IPV6 case AF_INET6: sinptr6 = (struct sockaddr_in6 *) &ifr->ifr_addr; if (ifi->ifi_addr == NULL) { ifi->ifi_addr = calloc(1, sizeof(struct sockaddr_in6)); if (ifi->ifi_addr == NULL) { goto gotError; } /* Some platforms (*BSD) inject the prefix in IPv6LL addresses */ /* We need to strip that out */ if (IN6_IS_ADDR_LINKLOCAL(&sinptr6->sin6_addr)) sinptr6->sin6_addr.s6_addr[2] = sinptr6->sin6_addr.s6_addr[3] = 0; memcpy(ifi->ifi_addr, sinptr6, sizeof(struct sockaddr_in6)); #ifdef SIOCGIFNETMASK_IN6 { struct in6_ifreq ifr6; if (sockf6 == -1) sockf6 = socket(AF_INET6, SOCK_DGRAM, 0); bzero(&ifr6, sizeof(ifr6)); memcpy(&ifr6.ifr_name, &ifr->ifr_name, sizeof(ifr6.ifr_name )); memcpy(&ifr6.ifr_ifru.ifru_addr, &ifr->ifr_addr, sizeof(ifr6.ifr_ifru.ifru_addr)); if (ioctl(sockf6, SIOCGIFNETMASK_IN6, &ifr6) < 0) goto gotError; ifi->ifi_netmask = (struct sockaddr*)calloc(1, sizeof(struct sockaddr_in6)); if (ifi->ifi_netmask == NULL) goto gotError; sinptr6 = (struct sockaddr_in6 *) &ifr6.ifr_ifru.ifru_addr; memcpy(ifi->ifi_netmask, sinptr6, sizeof(struct sockaddr_in6)); } #endif } break; #endif default: break; } } goto done; gotError: if (ifihead != NULL) { free_ifi_info(ifihead); ifihead = NULL; } done: if (buf != NULL) { free(buf); } if (sockfd != -1) { junk = close(sockfd); assert(junk == 0); } if (sockf6 != -1) { junk = close(sockf6); assert(junk == 0); } return(ifihead); /* pointer to first structure in linked list */ } /* end get_ifi_info3 */ /* include free_ifi_info */ void free_ifi_info(struct ifi_info *ifihead) { struct ifi_info *ifi, *ifinext; for (ifi = ifihead; ifi != NULL; ifi = ifinext) { if (ifi->ifi_addr != NULL) free(ifi->ifi_addr); if (ifi->ifi_brdaddr != NULL) free(ifi->ifi_brdaddr); if (ifi->ifi_dstaddr != NULL) free(ifi->ifi_dstaddr); ifinext = ifi->ifi_next; /* can't fetch ifi_next after free() */ free(ifi); /* the ifi_info{} itself */ } } /* end free_ifi_info */ ssize_t recvfrom_flags(int fd, void *ptr, size_t nbytes, int *flagsp, struct sockaddr *sa, socklen_t *salenptr, struct my_in_pktinfo *pktp, u_char *ttl) { struct msghdr msg; struct iovec iov[1]; ssize_t n; #ifdef CMSG_FIRSTHDR struct cmsghdr *cmptr; union { struct cmsghdr cm; char control[1024]; } control_un; *ttl = 255; // If kernel fails to provide TTL data then assume the TTL was 255 as it should be msg.msg_control = control_un.control; msg.msg_controllen = sizeof(control_un.control); msg.msg_flags = 0; #else memset(&msg, 0, sizeof(msg)); /* make certain msg_accrightslen = 0 */ #endif /* CMSG_FIRSTHDR */ msg.msg_name = (char *) sa; msg.msg_namelen = *salenptr; iov[0].iov_base = (char *)ptr; iov[0].iov_len = nbytes; msg.msg_iov = iov; msg.msg_iovlen = 1; if ( (n = recvmsg(fd, &msg, *flagsp)) < 0) return(n); *salenptr = msg.msg_namelen; /* pass back results */ if (pktp) { /* 0.0.0.0, i/f = -1 */ /* We set the interface to -1 so that the caller can tell whether we returned a meaningful value or just some default. Previously this code just set the value to 0, but I'm concerned that 0 might be a valid interface value. */ memset(pktp, 0, sizeof(struct my_in_pktinfo)); pktp->ipi_ifindex = -1; } /* end recvfrom_flags1 */ /* include recvfrom_flags2 */ #ifndef CMSG_FIRSTHDR #warning CMSG_FIRSTHDR not defined. Will not be able to determine destination address, received interface, etc. *flagsp = 0; /* pass back results */ return(n); #else *flagsp = msg.msg_flags; /* pass back results */ if (msg.msg_controllen < (socklen_t)sizeof(struct cmsghdr) || (msg.msg_flags & MSG_CTRUNC) || pktp == NULL) return(n); for (cmptr = CMSG_FIRSTHDR(&msg); cmptr != NULL; cmptr = CMSG_NXTHDR(&msg, cmptr)) { #ifdef IP_PKTINFO #if in_pktinfo_definition_is_missing struct in_pktinfo { int ipi_ifindex; struct in_addr ipi_spec_dst; struct in_addr ipi_addr; }; #endif if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_PKTINFO) { struct in_pktinfo *tmp; struct sockaddr_in *sin = (struct sockaddr_in*)&pktp->ipi_addr; tmp = (struct in_pktinfo *) CMSG_DATA(cmptr); sin->sin_family = AF_INET; sin->sin_addr = tmp->ipi_addr; sin->sin_port = 0; pktp->ipi_ifindex = tmp->ipi_ifindex; continue; } #endif #ifdef IP_RECVDSTADDR if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_RECVDSTADDR) { struct sockaddr_in *sin = (struct sockaddr_in*)&pktp->ipi_addr; sin->sin_family = AF_INET; sin->sin_addr = *(struct in_addr*)CMSG_DATA(cmptr); sin->sin_port = 0; continue; } #endif #ifdef IP_RECVIF if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_RECVIF) { struct sockaddr_dl *sdl = (struct sockaddr_dl *) CMSG_DATA(cmptr); #ifndef HAVE_BROKEN_RECVIF_NAME int nameLen = (sdl->sdl_nlen < IFI_NAME - 1) ? sdl->sdl_nlen : (IFI_NAME - 1); strncpy(pktp->ipi_ifname, sdl->sdl_data, nameLen); #endif pktp->ipi_ifindex = sdl->sdl_index; assert(pktp->ipi_ifname[IFI_NAME - 1] == 0); // null terminated because of memset above continue; } #endif #ifdef IP_RECVTTL if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_RECVTTL) { *ttl = *(u_char*)CMSG_DATA(cmptr); continue; } else if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_TTL) { // some implementations seem to send IP_TTL instead of IP_RECVTTL *ttl = *(int*)CMSG_DATA(cmptr); continue; } #endif #if defined(IPV6_PKTINFO) && HAVE_IPV6 if (cmptr->cmsg_level == IPPROTO_IPV6 && cmptr->cmsg_type == IPV6_PKTINFO) { struct sockaddr_in6 *sin6 = (struct sockaddr_in6*)&pktp->ipi_addr; struct in6_pktinfo *ip6_info = (struct in6_pktinfo*)CMSG_DATA(cmptr); sin6->sin6_family = AF_INET6; #ifndef NOT_HAVE_SA_LEN sin6->sin6_len = sizeof(*sin6); #endif sin6->sin6_addr = ip6_info->ipi6_addr; sin6->sin6_flowinfo = 0; sin6->sin6_scope_id = 0; sin6->sin6_port = 0; pktp->ipi_ifindex = ip6_info->ipi6_ifindex; continue; } #endif #if defined(IPV6_HOPLIMIT) && HAVE_IPV6 if (cmptr->cmsg_level == IPPROTO_IPV6 && cmptr->cmsg_type == IPV6_HOPLIMIT) { *ttl = *(int*)CMSG_DATA(cmptr); continue; } #endif assert(0); // unknown ancillary data } return(n); #endif /* CMSG_FIRSTHDR */ } // ********************************************************************************************** // daemonize the process. Adapted from "Unix Network Programming" vol 1 by Stevens, section 12.4. // Returns 0 on success, -1 on failure. #ifdef NOT_HAVE_DAEMON #include #include #include int daemon(int nochdir, int noclose) { switch (fork()) { case -1: return (-1); // Fork failed case 0: break; // Child -- continue default: _exit(0); // Parent -- exit } if (setsid() == -1) return(-1); signal(SIGHUP, SIG_IGN); switch (fork()) // Fork again, primarily for reasons of Unix trivia { case -1: return (-1); // Fork failed case 0: break; // Child -- continue default: _exit(0); // Parent -- exit } if (!nochdir) (void)chdir("/"); umask(0); if (!noclose) { int fd = open("/dev/null", O_RDWR, 0); if (fd != -1) { // Avoid unnecessarily duplicating a file descriptor to itself if (fd != STDIN_FILENO) (void)dup2(fd, STDIN_FILENO); if (fd != STDOUT_FILENO) (void)dup2(fd, STDOUT_FILENO); if (fd != STDERR_FILENO) (void)dup2(fd, STDERR_FILENO); if (fd != STDIN_FILENO && fd != STDOUT_FILENO && fd != STDERR_FILENO) (void)close (fd); } } return (0); } #endif /* NOT_HAVE_DAEMON */