/* -*- Mode: c; tab-width: 8; indent-tabs-mode: 1; c-basic-offset: 8; -*- */ /* * Copyright (c) 1994, 1995, 1996, 1997, 1998 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the Computer Systems * Engineering Group at Lawrence Berkeley Laboratory. * 4. Neither the name of the University nor of the Laboratory may be used * to endorse or promote products derived from this software without * specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #ifndef lint static const char rcsid[] _U_ = "@(#) $Header: /tcpdump/master/libpcap/inet.c,v 1.66.2.6 2007/06/11 09:52:04 guy Exp $ (LBL)"; #endif #ifdef HAVE_CONFIG_H #include "config.h" #endif #ifdef WIN32 #include #else /* WIN32 */ #include #ifndef MSDOS #include #endif #include #include #ifdef HAVE_SYS_SOCKIO_H #include #endif struct mbuf; /* Squelch compiler warnings on some platforms for */ struct rtentry; /* declarations in */ #include #include #endif /* WIN32 */ #include #include #include #include #include #include #if !defined(WIN32) && !defined(__BORLANDC__) #include #endif /* !WIN32 && !__BORLANDC__ */ #ifdef HAVE_LIMITS_H #include #else #define INT_MAX 2147483647 #endif #include "pcap-int.h" #ifdef HAVE_OS_PROTO_H #include "os-proto.h" #endif /* Not all systems have IFF_LOOPBACK */ #ifdef IFF_LOOPBACK #define ISLOOPBACK(name, flags) ((flags) & IFF_LOOPBACK) #else #define ISLOOPBACK(name, flags) ((name)[0] == 'l' && (name)[1] == 'o' && \ (isdigit((unsigned char)((name)[2])) || (name)[2] == '\0')) #endif struct sockaddr * dup_sockaddr(struct sockaddr *sa, size_t sa_length) { struct sockaddr *newsa; if ((newsa = malloc(sa_length)) == NULL) return (NULL); return (memcpy(newsa, sa, sa_length)); } static int get_instance(const char *name) { const char *cp, *endcp; int n; if (strcmp(name, "any") == 0) { /* * Give the "any" device an artificially high instance * number, so it shows up after all other non-loopback * interfaces. */ return INT_MAX; } endcp = name + strlen(name); for (cp = name; cp < endcp && !isdigit((unsigned char)*cp); ++cp) continue; if (isdigit((unsigned char)*cp)) n = atoi(cp); else n = 0; return (n); } int add_or_find_if(pcap_if_t **curdev_ret, pcap_if_t **alldevs, const char *name, u_int flags, const char *description, char *errbuf) { pcap_t *p; pcap_if_t *curdev, *prevdev, *nextdev; int this_instance; /* * Is there already an entry in the list for this interface? */ for (curdev = *alldevs; curdev != NULL; curdev = curdev->next) { if (strcmp(name, curdev->name) == 0) break; /* yes, we found it */ } if (curdev == NULL) { /* * No, we didn't find it. * * Can we open this interface for live capture? * * We do this check so that interfaces that are * supplied by the interface enumeration mechanism * we're using but that don't support packet capture * aren't included in the list. Loopback interfaces * on Solaris are an example of this; we don't just * omit loopback interfaces on all platforms because * you *can* capture on loopback interfaces on some * OSes. * * On OS X, we don't do this check if the device * name begins with "wlt"; at least some versions * of OS X offer monitor mode capturing by having * a separate "monitor mode" device for each wireless * adapter, rather than by implementing the ioctls * that {Free,Net,Open,DragonFly}BSD provide. * Opening that device puts the adapter into monitor * mode, which, at least for some adapters, causes * them to deassociate from the network with which * they're associated. * * Instead, we try to open the corresponding "en" * device (so that we don't end up with, for users * without sufficient privilege to open capture * devices, a list of adapters that only includes * the wlt devices). */ #ifdef __APPLE__ if (strncmp(name, "wlt", 3) == 0) { char *en_name; size_t en_name_len; /* * Try to allocate a buffer for the "en" * device's name. */ en_name_len = strlen(name) - 1; en_name = malloc(en_name_len + 1); if (en_name == NULL) { (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, "malloc: %s", pcap_strerror(errno)); return (-1); } strcpy(en_name, "en"); strcat(en_name, name + 3); p = pcap_open_live(en_name, 68, 0, 0, errbuf); free(en_name); } else #endif /* __APPLE */ p = pcap_open_live(name, 68, 0, 0, errbuf); if (p == NULL) { /* * No. Don't bother including it. * Don't treat this as an error, though. */ *curdev_ret = NULL; return (0); } pcap_close(p); /* * Yes, we can open it. * Allocate a new entry. */ curdev = malloc(sizeof(pcap_if_t)); if (curdev == NULL) { (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, "malloc: %s", pcap_strerror(errno)); return (-1); } /* * Fill in the entry. */ curdev->next = NULL; curdev->name = strdup(name); if (curdev->name == NULL) { (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, "malloc: %s", pcap_strerror(errno)); free(curdev); return (-1); } if (description != NULL) { /* * We have a description for this interface. */ curdev->description = strdup(description); if (curdev->description == NULL) { (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, "malloc: %s", pcap_strerror(errno)); free(curdev->name); free(curdev); return (-1); } } else { /* * We don't. */ curdev->description = NULL; } curdev->addresses = NULL; /* list starts out as empty */ curdev->flags = 0; if (ISLOOPBACK(name, flags)) curdev->flags |= PCAP_IF_LOOPBACK; /* * Add it to the list, in the appropriate location. * First, get the instance number of this interface. */ this_instance = get_instance(name); /* * Now look for the last interface with an instance number * less than or equal to the new interface's instance * number - except that non-loopback interfaces are * arbitrarily treated as having interface numbers less * than those of loopback interfaces, so the loopback * interfaces are put at the end of the list. * * We start with "prevdev" being NULL, meaning we're before * the first element in the list. */ prevdev = NULL; for (;;) { /* * Get the interface after this one. */ if (prevdev == NULL) { /* * The next element is the first element. */ nextdev = *alldevs; } else nextdev = prevdev->next; /* * Are we at the end of the list? */ if (nextdev == NULL) { /* * Yes - we have to put the new entry * after "prevdev". */ break; } /* * Is the new interface a non-loopback interface * and the next interface a loopback interface? */ if (!(curdev->flags & PCAP_IF_LOOPBACK) && (nextdev->flags & PCAP_IF_LOOPBACK)) { /* * Yes, we should put the new entry * before "nextdev", i.e. after "prevdev". */ break; } /* * Is the new interface's instance number less * than the next interface's instance number, * and is it the case that the new interface is a * non-loopback interface or the next interface is * a loopback interface? * * (The goal of both loopback tests is to make * sure that we never put a loopback interface * before any non-loopback interface and that we * always put a non-loopback interface before all * loopback interfaces.) */ if (this_instance < get_instance(nextdev->name) && (!(curdev->flags & PCAP_IF_LOOPBACK) || (nextdev->flags & PCAP_IF_LOOPBACK))) { /* * Yes - we should put the new entry * before "nextdev", i.e. after "prevdev". */ break; } prevdev = nextdev; } /* * Insert before "nextdev". */ curdev->next = nextdev; /* * Insert after "prevdev" - unless "prevdev" is null, * in which case this is the first interface. */ if (prevdev == NULL) { /* * This is the first interface. Pass back a * pointer to it, and put "curdev" before * "nextdev". */ *alldevs = curdev; } else prevdev->next = curdev; } *curdev_ret = curdev; return (0); } int add_addr_to_iflist(pcap_if_t **alldevs, const char *name, u_int flags, struct sockaddr *addr, size_t addr_size, struct sockaddr *netmask, size_t netmask_size, struct sockaddr *broadaddr, size_t broadaddr_size, struct sockaddr *dstaddr, size_t dstaddr_size, char *errbuf) { pcap_if_t *curdev; pcap_addr_t *curaddr, *prevaddr, *nextaddr; if (add_or_find_if(&curdev, alldevs, name, flags, NULL, errbuf) == -1) { /* * Error - give up. */ return (-1); } if (curdev == NULL) { /* * Device wasn't added because it can't be opened. * Not a fatal error. */ return (0); } /* * "curdev" is an entry for this interface; add an entry for this * address to its list of addresses. * * Allocate the new entry and fill it in. */ curaddr = malloc(sizeof(pcap_addr_t)); if (curaddr == NULL) { (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, "malloc: %s", pcap_strerror(errno)); return (-1); } curaddr->next = NULL; if (addr != NULL) { curaddr->addr = dup_sockaddr(addr, addr_size); if (curaddr->addr == NULL) { (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, "malloc: %s", pcap_strerror(errno)); free(curaddr); return (-1); } } else curaddr->addr = NULL; if (netmask != NULL) { curaddr->netmask = dup_sockaddr(netmask, netmask_size); if (curaddr->netmask == NULL) { (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, "malloc: %s", pcap_strerror(errno)); if (curaddr->addr != NULL) free(curaddr->addr); free(curaddr); return (-1); } } else curaddr->netmask = NULL; if (broadaddr != NULL) { curaddr->broadaddr = dup_sockaddr(broadaddr, broadaddr_size); if (curaddr->broadaddr == NULL) { (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, "malloc: %s", pcap_strerror(errno)); if (curaddr->netmask != NULL) free(curaddr->netmask); if (curaddr->addr != NULL) free(curaddr->addr); free(curaddr); return (-1); } } else curaddr->broadaddr = NULL; if (dstaddr != NULL) { curaddr->dstaddr = dup_sockaddr(dstaddr, dstaddr_size); if (curaddr->dstaddr == NULL) { (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, "malloc: %s", pcap_strerror(errno)); if (curaddr->broadaddr != NULL) free(curaddr->broadaddr); if (curaddr->netmask != NULL) free(curaddr->netmask); if (curaddr->addr != NULL) free(curaddr->addr); free(curaddr); return (-1); } } else curaddr->dstaddr = NULL; /* * Find the end of the list of addresses. */ for (prevaddr = curdev->addresses; prevaddr != NULL; prevaddr = nextaddr) { nextaddr = prevaddr->next; if (nextaddr == NULL) { /* * This is the end of the list. */ break; } } if (prevaddr == NULL) { /* * The list was empty; this is the first member. */ curdev->addresses = curaddr; } else { /* * "prevaddr" is the last member of the list; append * this member to it. */ prevaddr->next = curaddr; } return (0); } int pcap_add_if(pcap_if_t **devlist, const char *name, u_int flags, const char *description, char *errbuf) { pcap_if_t *curdev; return (add_or_find_if(&curdev, devlist, name, flags, description, errbuf)); } /* * Free a list of interfaces. */ void pcap_freealldevs(pcap_if_t *alldevs) { pcap_if_t *curdev, *nextdev; pcap_addr_t *curaddr, *nextaddr; for (curdev = alldevs; curdev != NULL; curdev = nextdev) { nextdev = curdev->next; /* * Free all addresses. */ for (curaddr = curdev->addresses; curaddr != NULL; curaddr = nextaddr) { nextaddr = curaddr->next; if (curaddr->addr) free(curaddr->addr); if (curaddr->netmask) free(curaddr->netmask); if (curaddr->broadaddr) free(curaddr->broadaddr); if (curaddr->dstaddr) free(curaddr->dstaddr); free(curaddr); } /* * Free the name string. */ free(curdev->name); /* * Free the description string, if any. */ if (curdev->description != NULL) free(curdev->description); /* * Free the interface. */ free(curdev); } } #if !defined(WIN32) && !defined(MSDOS) /* * Return the name of a network interface attached to the system, or NULL * if none can be found. The interface must be configured up; the * lowest unit number is preferred; loopback is ignored. */ char * pcap_lookupdev(errbuf) register char *errbuf; { pcap_if_t *alldevs; /* for old BSD systems, including bsdi3 */ #ifndef IF_NAMESIZE #define IF_NAMESIZE IFNAMSIZ #endif static char device[IF_NAMESIZE + 1]; char *ret; if (pcap_findalldevs(&alldevs, errbuf) == -1) return (NULL); if (alldevs == NULL || (alldevs->flags & PCAP_IF_LOOPBACK)) { /* * There are no devices on the list, or the first device * on the list is a loopback device, which means there * are no non-loopback devices on the list. This means * we can't return any device. * * XXX - why not return a loopback device? If we can't * capture on it, it won't be on the list, and if it's * on the list, there aren't any non-loopback devices, * so why not just supply it as the default device? */ (void)strlcpy(errbuf, "no suitable device found", PCAP_ERRBUF_SIZE); ret = NULL; } else { /* * Return the name of the first device on the list. */ (void)strlcpy(device, alldevs->name, sizeof(device)); ret = device; } pcap_freealldevs(alldevs); return (ret); } int pcap_lookupnet(device, netp, maskp, errbuf) register const char *device; register bpf_u_int32 *netp, *maskp; register char *errbuf; { register int fd; register struct sockaddr_in *sin4; struct ifreq ifr; /* * The pseudo-device "any" listens on all interfaces and therefore * has the network address and -mask "0.0.0.0" therefore catching * all traffic. Using NULL for the interface is the same as "any". */ if (!device || strcmp(device, "any") == 0 #ifdef HAVE_DAG_API || strstr(device, "dag") != NULL #endif #ifdef HAVE_SEPTEL_API || strstr(device, "septel") != NULL #endif ) { *netp = *maskp = 0; return 0; } fd = socket(AF_INET, SOCK_DGRAM, 0); if (fd < 0) { (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, "socket: %s", pcap_strerror(errno)); return (-1); } memset(&ifr, 0, sizeof(ifr)); #ifdef linux /* XXX Work around Linux kernel bug */ ifr.ifr_addr.sa_family = AF_INET; #endif (void)strncpy(ifr.ifr_name, device, sizeof(ifr.ifr_name)); if (ioctl(fd, SIOCGIFADDR, (char *)&ifr) < 0) { if (errno == EADDRNOTAVAIL) { (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: no IPv4 address assigned", device); } else { (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, "SIOCGIFADDR: %s: %s", device, pcap_strerror(errno)); } (void)close(fd); return (-1); } sin4 = (struct sockaddr_in *)&ifr.ifr_addr; *netp = sin4->sin_addr.s_addr; if (ioctl(fd, SIOCGIFNETMASK, (char *)&ifr) < 0) { (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, "SIOCGIFNETMASK: %s: %s", device, pcap_strerror(errno)); (void)close(fd); return (-1); } (void)close(fd); *maskp = sin4->sin_addr.s_addr; if (*maskp == 0) { if (IN_CLASSA(*netp)) *maskp = IN_CLASSA_NET; else if (IN_CLASSB(*netp)) *maskp = IN_CLASSB_NET; else if (IN_CLASSC(*netp)) *maskp = IN_CLASSC_NET; else { (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, "inet class for 0x%x unknown", *netp); return (-1); } } *netp &= *maskp; return (0); } #elif defined(WIN32) /* * Return the name of a network interface attached to the system, or NULL * if none can be found. The interface must be configured up; the * lowest unit number is preferred; loopback is ignored. */ char * pcap_lookupdev(errbuf) register char *errbuf; { DWORD dwVersion; DWORD dwWindowsMajorVersion; dwVersion = GetVersion(); /* get the OS version */ dwWindowsMajorVersion = (DWORD)(LOBYTE(LOWORD(dwVersion))); if (dwVersion >= 0x80000000 && dwWindowsMajorVersion >= 4) { /* * Windows 95, 98, ME. */ ULONG NameLength = 8192; static char AdaptersName[8192]; if (PacketGetAdapterNames(AdaptersName,&NameLength) ) return (AdaptersName); else return NULL; } else { /* * Windows NT (NT 4.0, W2K, WXP). Convert the names to UNICODE for backward compatibility */ ULONG NameLength = 8192; static WCHAR AdaptersName[8192]; char *tAstr; WCHAR *tUstr; WCHAR *TAdaptersName = (WCHAR*)malloc(8192 * sizeof(WCHAR)); int NAdapts = 0; if(TAdaptersName == NULL) { (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, "memory allocation failure"); return NULL; } if ( !PacketGetAdapterNames((PTSTR)TAdaptersName,&NameLength) ) { (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, "PacketGetAdapterNames: %s", pcap_win32strerror()); free(TAdaptersName); return NULL; } tAstr = (char*)TAdaptersName; tUstr = (WCHAR*)AdaptersName; /* * Convert and copy the device names */ while(sscanf(tAstr, "%S", tUstr) > 0) { tAstr += strlen(tAstr) + 1; tUstr += wcslen(tUstr) + 1; NAdapts ++; } tAstr++; *tUstr = 0; tUstr++; /* * Copy the descriptions */ while(NAdapts--) { strcpy((char*)tUstr, tAstr); (char*)tUstr += strlen(tAstr) + 1;; tAstr += strlen(tAstr) + 1; } free(TAdaptersName); return (char *)(AdaptersName); } } int pcap_lookupnet(device, netp, maskp, errbuf) register const char *device; register bpf_u_int32 *netp, *maskp; register char *errbuf; { /* * We need only the first IPv4 address, so we must scan the array returned by PacketGetNetInfo() * in order to skip non IPv4 (i.e. IPv6 addresses) */ npf_if_addr if_addrs[MAX_NETWORK_ADDRESSES]; LONG if_addr_size = 1; struct sockaddr_in *t_addr; unsigned int i; if (!PacketGetNetInfoEx((void *)device, if_addrs, &if_addr_size)) { *netp = *maskp = 0; return (0); } for(i=0; isin_addr.S_un.S_addr; t_addr = (struct sockaddr_in *) &(if_addrs[i].SubnetMask); *maskp = t_addr->sin_addr.S_un.S_addr; *netp &= *maskp; return (0); } } *netp = *maskp = 0; return (0); } #endif /* !WIN32 && !MSDOS */