diff options
Diffstat (limited to 'lib/libpcap/libpcap/fad-gifc.c')
| -rw-r--r-- | lib/libpcap/libpcap/fad-gifc.c | 431 |
1 files changed, 431 insertions, 0 deletions
diff --git a/lib/libpcap/libpcap/fad-gifc.c b/lib/libpcap/libpcap/fad-gifc.c new file mode 100644 index 0000000..6b16127 --- /dev/null +++ b/lib/libpcap/libpcap/fad-gifc.c @@ -0,0 +1,431 @@ +/* -*- 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. + */ + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +#include <sys/param.h> +#include <sys/ioctl.h> +#include <sys/socket.h> +#ifdef HAVE_SYS_SOCKIO_H +#include <sys/sockio.h> +#endif +#include <sys/time.h> /* concession to AIX */ + +struct mbuf; /* Squelch compiler warnings on some platforms for */ +struct rtentry; /* declarations in <net/if.h> */ +#include <net/if.h> +#include <netinet/in.h> + +#include <ctype.h> +#include <errno.h> +#include <memory.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#ifdef HAVE_LIMITS_H +#include <limits.h> +#else +#define INT_MAX 2147483647 +#endif + +#include "pcap-int.h" + +#ifdef HAVE_OS_PROTO_H +#include "os-proto.h" +#endif + +/* + * This is fun. + * + * In older BSD systems, socket addresses were fixed-length, and + * "sizeof (struct sockaddr)" gave the size of the structure. + * All addresses fit within a "struct sockaddr". + * + * In newer BSD systems, the socket address is variable-length, and + * there's an "sa_len" field giving the length of the structure; + * this allows socket addresses to be longer than 2 bytes of family + * and 14 bytes of data. + * + * Some commercial UNIXes use the old BSD scheme, some use the RFC 2553 + * variant of the old BSD scheme (with "struct sockaddr_storage" rather + * than "struct sockaddr"), and some use the new BSD scheme. + * + * Some versions of GNU libc use neither scheme, but has an "SA_LEN()" + * macro that determines the size based on the address family. Other + * versions don't have "SA_LEN()" (as it was in drafts of RFC 2553 + * but not in the final version). + * + * We assume that a UNIX that doesn't have "getifaddrs()" and doesn't have + * SIOCGLIFCONF, but has SIOCGIFCONF, uses "struct sockaddr" for the + * address in an entry returned by SIOCGIFCONF. + */ +#ifndef SA_LEN +#ifdef HAVE_STRUCT_SOCKADDR_SA_LEN +#define SA_LEN(addr) ((addr)->sa_len) +#else /* HAVE_STRUCT_SOCKADDR_SA_LEN */ +#define SA_LEN(addr) (sizeof (struct sockaddr)) +#endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */ +#endif /* SA_LEN */ + +/* + * This is also fun. + * + * There is no ioctl that returns the amount of space required for all + * the data that SIOCGIFCONF could return, and if a buffer is supplied + * that's not large enough for all the data SIOCGIFCONF could return, + * on at least some platforms it just returns the data that'd fit with + * no indication that there wasn't enough room for all the data, much + * less an indication of how much more room is required. + * + * The only way to ensure that we got all the data is to pass a buffer + * large enough that the amount of space in the buffer *not* filled in + * is greater than the largest possible entry. + * + * We assume that's "sizeof(ifreq.ifr_name)" plus 255, under the assumption + * that no address is more than 255 bytes (on systems where the "sa_len" + * field in a "struct sockaddr" is 1 byte, e.g. newer BSDs, that's the + * case, and addresses are unlikely to be bigger than that in any case). + */ +#define MAX_SA_LEN 255 + +/* + * Get a list of all interfaces that are up and that we can open. + * Returns -1 on error, 0 otherwise. + * The list, as returned through "alldevsp", may be null if no interfaces + * were up and could be opened. + * + * This is the implementation used on platforms that have SIOCGIFCONF but + * don't have any other mechanism for getting a list of interfaces. + * + * XXX - or platforms that have other, better mechanisms but for which + * we don't yet have code to use that mechanism; I think there's a better + * way on Linux, for example, but if that better way is "getifaddrs()", + * we already have that. + */ +int +pcap_findalldevs_interfaces(pcap_if_list_t *devlistp, char *errbuf, + int (*check_usable)(const char *), get_if_flags_func get_flags_func) +{ + register int fd; + register struct ifreq *ifrp, *ifend, *ifnext; + size_t n; + struct ifconf ifc; + char *buf = NULL; + unsigned buf_size; +#if defined (HAVE_SOLARIS) || defined (HAVE_HPUX10_20_OR_LATER) + char *p, *q; +#endif + struct ifreq ifrflags, ifrnetmask, ifrbroadaddr, ifrdstaddr; + struct sockaddr *netmask, *broadaddr, *dstaddr; + size_t netmask_size, broadaddr_size, dstaddr_size; + int ret = 0; + + /* + * Create a socket from which to fetch the list of interfaces. + */ + fd = socket(AF_INET, SOCK_DGRAM, 0); + if (fd < 0) { + pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE, + errno, "socket"); + return (-1); + } + + /* + * Start with an 8K buffer, and keep growing the buffer until + * we have more than "sizeof(ifrp->ifr_name) + MAX_SA_LEN" + * bytes left over in the buffer or we fail to get the + * interface list for some reason other than EINVAL (which is + * presumed here to mean "buffer is too small"). + */ + buf_size = 8192; + for (;;) { + /* + * Don't let the buffer size get bigger than INT_MAX. + */ + if (buf_size > INT_MAX) { + (void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE, + "interface information requires more than %u bytes", + INT_MAX); + (void)close(fd); + return (-1); + } + buf = malloc(buf_size); + if (buf == NULL) { + pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE, + errno, "malloc"); + (void)close(fd); + return (-1); + } + + ifc.ifc_len = buf_size; + ifc.ifc_buf = buf; + memset(buf, 0, buf_size); + if (ioctl(fd, SIOCGIFCONF, (char *)&ifc) < 0 + && errno != EINVAL) { + pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE, + errno, "SIOCGIFCONF"); + (void)close(fd); + free(buf); + return (-1); + } + if (ifc.ifc_len < (int)buf_size && + (buf_size - ifc.ifc_len) > sizeof(ifrp->ifr_name) + MAX_SA_LEN) + break; + free(buf); + buf_size *= 2; + } + + ifrp = (struct ifreq *)buf; + ifend = (struct ifreq *)(buf + ifc.ifc_len); + + for (; ifrp < ifend; ifrp = ifnext) { + /* + * XXX - what if this isn't an IPv4 address? Can + * we still get the netmask, etc. with ioctls on + * an IPv4 socket? + * + * The answer is probably platform-dependent, and + * if the answer is "no" on more than one platform, + * the way you work around it is probably platform- + * dependent as well. + */ + n = SA_LEN(&ifrp->ifr_addr) + sizeof(ifrp->ifr_name); + if (n < sizeof(*ifrp)) + ifnext = ifrp + 1; + else + ifnext = (struct ifreq *)((char *)ifrp + n); + + /* + * XXX - The 32-bit compatibility layer for Linux on IA-64 + * is slightly broken. It correctly converts the structures + * to and from kernel land from 64 bit to 32 bit but + * doesn't update ifc.ifc_len, leaving it larger than the + * amount really used. This means we read off the end + * of the buffer and encounter an interface with an + * "empty" name. Since this is highly unlikely to ever + * occur in a valid case we can just finish looking for + * interfaces if we see an empty name. + */ + if (!(*ifrp->ifr_name)) + break; + + /* + * Skip entries that begin with "dummy". + * XXX - what are these? Is this Linux-specific? + * Are there platforms on which we shouldn't do this? + */ + if (strncmp(ifrp->ifr_name, "dummy", 5) == 0) + continue; + + /* + * Can we capture on this device? + */ + if (!(*check_usable)(ifrp->ifr_name)) { + /* + * No. + */ + continue; + } + + /* + * Get the flags for this interface. + */ + strncpy(ifrflags.ifr_name, ifrp->ifr_name, + sizeof(ifrflags.ifr_name)); + if (ioctl(fd, SIOCGIFFLAGS, (char *)&ifrflags) < 0) { + if (errno == ENXIO) + continue; + pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE, + errno, "SIOCGIFFLAGS: %.*s", + (int)sizeof(ifrflags.ifr_name), + ifrflags.ifr_name); + ret = -1; + break; + } + + /* + * Get the netmask for this address on this interface. + */ + strncpy(ifrnetmask.ifr_name, ifrp->ifr_name, + sizeof(ifrnetmask.ifr_name)); + memcpy(&ifrnetmask.ifr_addr, &ifrp->ifr_addr, + sizeof(ifrnetmask.ifr_addr)); + if (ioctl(fd, SIOCGIFNETMASK, (char *)&ifrnetmask) < 0) { + if (errno == EADDRNOTAVAIL) { + /* + * Not available. + */ + netmask = NULL; + netmask_size = 0; + } else { + pcap_fmt_errmsg_for_errno(errbuf, + PCAP_ERRBUF_SIZE, errno, + "SIOCGIFNETMASK: %.*s", + (int)sizeof(ifrnetmask.ifr_name), + ifrnetmask.ifr_name); + ret = -1; + break; + } + } else { + netmask = &ifrnetmask.ifr_addr; + netmask_size = SA_LEN(netmask); + } + + /* + * Get the broadcast address for this address on this + * interface (if any). + */ + if (ifrflags.ifr_flags & IFF_BROADCAST) { + strncpy(ifrbroadaddr.ifr_name, ifrp->ifr_name, + sizeof(ifrbroadaddr.ifr_name)); + memcpy(&ifrbroadaddr.ifr_addr, &ifrp->ifr_addr, + sizeof(ifrbroadaddr.ifr_addr)); + if (ioctl(fd, SIOCGIFBRDADDR, + (char *)&ifrbroadaddr) < 0) { + if (errno == EADDRNOTAVAIL) { + /* + * Not available. + */ + broadaddr = NULL; + broadaddr_size = 0; + } else { + pcap_fmt_errmsg_for_errno(errbuf, + PCAP_ERRBUF_SIZE, errno, + "SIOCGIFBRDADDR: %.*s", + (int)sizeof(ifrbroadaddr.ifr_name), + ifrbroadaddr.ifr_name); + ret = -1; + break; + } + } else { + broadaddr = &ifrbroadaddr.ifr_broadaddr; + broadaddr_size = SA_LEN(broadaddr); + } + } else { + /* + * Not a broadcast interface, so no broadcast + * address. + */ + broadaddr = NULL; + broadaddr_size = 0; + } + + /* + * Get the destination address for this address on this + * interface (if any). + */ + if (ifrflags.ifr_flags & IFF_POINTOPOINT) { + strncpy(ifrdstaddr.ifr_name, ifrp->ifr_name, + sizeof(ifrdstaddr.ifr_name)); + memcpy(&ifrdstaddr.ifr_addr, &ifrp->ifr_addr, + sizeof(ifrdstaddr.ifr_addr)); + if (ioctl(fd, SIOCGIFDSTADDR, + (char *)&ifrdstaddr) < 0) { + if (errno == EADDRNOTAVAIL) { + /* + * Not available. + */ + dstaddr = NULL; + dstaddr_size = 0; + } else { + pcap_fmt_errmsg_for_errno(errbuf, + PCAP_ERRBUF_SIZE, errno, + "SIOCGIFDSTADDR: %.*s", + (int)sizeof(ifrdstaddr.ifr_name), + ifrdstaddr.ifr_name); + ret = -1; + break; + } + } else { + dstaddr = &ifrdstaddr.ifr_dstaddr; + dstaddr_size = SA_LEN(dstaddr); + } + } else { + /* + * Not a point-to-point interface, so no destination + * address. + */ + dstaddr = NULL; + dstaddr_size = 0; + } + +#if defined (HAVE_SOLARIS) || defined (HAVE_HPUX10_20_OR_LATER) + /* + * If this entry has a colon followed by a number at + * the end, it's a logical interface. Those are just + * the way you assign multiple IP addresses to a real + * interface, so an entry for a logical interface should + * be treated like the entry for the real interface; + * we do that by stripping off the ":" and the number. + */ + p = strchr(ifrp->ifr_name, ':'); + if (p != NULL) { + /* + * We have a ":"; is it followed by a number? + */ + q = p + 1; + while (isdigit((unsigned char)*q)) + q++; + if (*q == '\0') { + /* + * All digits after the ":" until the end. + * Strip off the ":" and everything after + * it. + */ + *p = '\0'; + } + } +#endif + + /* + * Add information for this address to the list. + */ + if (add_addr_to_if(devlistp, ifrp->ifr_name, + ifrflags.ifr_flags, get_flags_func, + &ifrp->ifr_addr, SA_LEN(&ifrp->ifr_addr), + netmask, netmask_size, broadaddr, broadaddr_size, + dstaddr, dstaddr_size, errbuf) < 0) { + ret = -1; + break; + } + } + free(buf); + (void)close(fd); + + return (ret); +} |