/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright 2007 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ #pragma ident "%Z%%M% %I% %E% SMI" /* SunOS */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "snoop.h" /* * Old header format. * Actually two concatenated structs: nit_bufhdr + nit_head */ struct ohdr { /* nit_bufhdr */ int o_msglen; int o_totlen; /* nit_head */ struct timeval o_time; int o_drops; int o_len; }; static void scan(char *, int, int, int, int, void (*)(), int, int, int); void convert_to_network(); void convert_from_network(); static void convert_old(struct ohdr *); extern sigjmp_buf jmp_env, ojmp_env; static dlpi_info_t dlinfo; static char *bufp; /* pointer to read buffer */ static int strioctl(int, int, int, int, void *); /* * Open up the device in raw mode and passive mode * (see dlpi_open(3DLPI)) and start finding out something about it, * especially stuff about the data link headers. We need that information * to build the proper packet filters. */ boolean_t check_device(dlpi_handle_t *dhp, char **devicep) { int retval; /* * Determine which network device * to use if none given. * Should get back a value like "le0". */ if (*devicep == NULL) { char *cbuf; static struct ifconf ifc; static struct ifreq *ifr; int s; int n; int numifs; unsigned bufsize; if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0) pr_err("socket"); if (ioctl(s, SIOCGIFNUM, (char *)&numifs) < 0) { pr_err("check_device: ioctl SIOCGIFNUM"); (void) close(s); s = -1; return (B_FALSE); } bufsize = numifs * sizeof (struct ifreq); cbuf = (char *)malloc(bufsize); if (cbuf == NULL) { pr_err("out of memory\n"); (void) close(s); s = -1; return (B_FALSE); } ifc.ifc_len = bufsize; ifc.ifc_buf = cbuf; if (ioctl(s, SIOCGIFCONF, (char *)&ifc) < 0) { pr_err("check_device: ioctl SIOCGIFCONF"); (void) close(s); s = -1; (void) free(cbuf); return (B_FALSE); } n = ifc.ifc_len / sizeof (struct ifreq); ifr = ifc.ifc_req; for (; n > 0; n--, ifr++) { if (strchr(ifr->ifr_name, ':') != NULL) continue; if (ioctl(s, SIOCGIFFLAGS, (char *)ifr) < 0) pr_err("ioctl SIOCGIFFLAGS"); if ((ifr->ifr_flags & (IFF_VIRTUAL|IFF_LOOPBACK|IFF_UP| IFF_RUNNING)) == (IFF_UP|IFF_RUNNING)) break; } if (n == 0) pr_err("No network interface devices found"); *devicep = ifr->ifr_name; (void) close(s); } retval = dlpi_open(*devicep, dhp, DLPI_PASSIVE|DLPI_RAW); if (retval != DLPI_SUCCESS) { pr_err("cannot open \"%s\": %s", *devicep, dlpi_strerror(retval)); } if ((retval = dlpi_info(*dhp, &dlinfo, 0)) != DLPI_SUCCESS) pr_errdlpi(*dhp, "dlpi_info failed", retval); for (interface = &INTERFACES[0]; interface->mac_type != -1; interface++) if (interface->mac_type == dlinfo.di_mactype) break; /* allow limited functionality even if interface isn't known */ if (interface->mac_type == -1) { (void) fprintf(stderr, "snoop: WARNING: Mac Type = %x " "not supported\n", dlinfo.di_mactype); } /* for backward compatibility, allow known interface mtu_sizes */ if (interface->mtu_size > dlinfo.di_max_sdu) dlinfo.di_max_sdu = interface->mtu_size; return (interface->try_kernel_filter); } /* * Do whatever is necessary to initialize the interface * for packet capture. Bind the device opened in check_device(), set * promiscuous mode, push the streams buffer module and packet filter * module, set various buffer parameters. */ void initdevice(dlpi_handle_t dh, ulong_t snaplen, ulong_t chunksize, struct timeval *timeout, struct Pf_ext_packetfilt *fp) { extern int Pflg; int retv; int netfd; retv = dlpi_bind(dh, DLPI_ANY_SAP, NULL); if (retv != DLPI_SUCCESS) pr_errdlpi(dh, "cannot bind on", retv); (void) fprintf(stderr, "Using device %s ", dlpi_linkname(dh)); /* * If Pflg not set - use physical level * promiscuous mode. Otherwise - just SAP level. */ if (!Pflg) { (void) fprintf(stderr, "(promiscuous mode)\n"); retv = dlpi_promiscon(dh, DL_PROMISC_PHYS); if (retv != DLPI_SUCCESS) { pr_errdlpi(dh, "promiscuous mode(physical) failed", retv); } } else { (void) fprintf(stderr, "(non promiscuous)\n"); retv = dlpi_promiscon(dh, DL_PROMISC_MULTI); if (retv != DLPI_SUCCESS) { pr_errdlpi(dh, "promiscuous mode(multicast) failed", retv); } } retv = dlpi_promiscon(dh, DL_PROMISC_SAP); if (retv != DLPI_SUCCESS) pr_errdlpi(dh, "promiscuous mode(SAP) failed", retv); netfd = dlpi_fd(dh); if (fp) { /* * push and configure the packet filtering module */ if (ioctl(netfd, I_PUSH, "pfmod") < 0) pr_errdlpi(dh, "cannot push \"pfmod\"", DL_SYSERR); if (strioctl(netfd, PFIOCSETF, -1, sizeof (*fp), (char *)fp) < 0) pr_errdlpi(dh, "PFIOCSETF", DL_SYSERR); } if (ioctl(netfd, I_PUSH, "bufmod") < 0) pr_errdlpi(dh, "cannot push \"bufmod\"", DL_SYSERR); if (strioctl(netfd, SBIOCSTIME, -1, sizeof (struct timeval), (char *)timeout) < 0) pr_errdlpi(dh, "SBIOCSTIME", DL_SYSERR); if (strioctl(netfd, SBIOCSCHUNK, -1, sizeof (uint_t), (char *)&chunksize) < 0) pr_errdlpi(dh, "SBIOCGCHUNK", DL_SYSERR); if (strioctl(netfd, SBIOCSSNAP, -1, sizeof (uint_t), (char *)&snaplen) < 0) pr_errdlpi(dh, "SBIOCSSNAP", DL_SYSERR); /* * Flush the read queue, to get rid of anything that * accumulated before the device reached its final configuration. */ if (ioctl(netfd, I_FLUSH, FLUSHR) < 0) pr_errdlpi(dh, "cannot flush \"I_FLUSH\"", DL_SYSERR); } /* * Read packets from the network. Initdevice is called in * here to set up the network interface for reading of * raw ethernet packets in promiscuous mode into a buffer. * Packets are read and either written directly to a file * or interpreted for display on the fly. */ void net_read(dlpi_handle_t dh, size_t chunksize, int filter, void (*proc)(), int flags) { int retval; extern int count; size_t msglen; count = 0; /* allocate a read buffer */ bufp = malloc(chunksize); if (bufp == NULL) pr_err("no memory for %d buffer", chunksize); /* * read frames */ for (;;) { msglen = chunksize; retval = dlpi_recv(dh, NULL, NULL, bufp, &msglen, -1, NULL); if (retval != DLPI_SUCCESS || quitting) break; if (msglen != 0) scan(bufp, msglen, filter, 0, 0, proc, 0, 0, flags); } free(bufp); if (!quitting) pr_errdlpi(dh, "network read failed", retval); } #ifdef DEBUG /* * corrupt: simulate packet corruption for debugging interpreters */ void corrupt(volatile char *pktp, volatile char *pstop, char *buf, volatile char *bufstop) { int c; int i; int p; int li = rand() % (pstop - pktp - 1) + 1; volatile char *pp = pktp; volatile char *pe = bufstop < pstop ? bufstop : pstop; if (pktp < buf || pktp > bufstop) return; for (pp = pktp; pp < pe; pp += li) { c = ((pe - pp) < li ? pe - pp : li); i = (rand() % c)>>1; while (--i > 0) { p = (rand() % c); pp[p] = (unsigned char)(rand() & 0xFF); } } } #endif /* DEBUG */ static void scan(char *buf, int len, int filter, int cap, int old, void (*proc)(), int first, int last, int flags) { volatile char *bp, *bufstop; volatile struct sb_hdr *hdrp; volatile struct sb_hdr nhdr, *nhdrp; volatile char *pktp; volatile struct timeval last_timestamp; volatile int header_okay; extern int count, maxcount; extern int snoop_nrecover; #ifdef DEBUG extern int zflg; #endif /* DEBUG */ proc(0, 0, 0); bufstop = buf + len; /* * * Loop through each packet in the buffer */ last_timestamp.tv_sec = 0; (void) memcpy((char *)ojmp_env, (char *)jmp_env, sizeof (jmp_env)); for (bp = buf; bp < bufstop; bp += nhdrp->sbh_totlen) { /* * Gracefully exit if user terminates */ if (quitting) break; /* * Global error recocery: Prepare to continue when a corrupt * packet or header is encountered. */ if (sigsetjmp(jmp_env, 1)) { goto err; } header_okay = 0; hdrp = (struct sb_hdr *)bp; nhdrp = hdrp; pktp = (char *)hdrp + sizeof (*hdrp); /* * If reading a capture file * convert the headers from network * byte order (for little-endians like X86) */ if (cap) { /* * If the packets come from an old * capture file, convert the header. */ if (old) { convert_old((struct ohdr *)hdrp); } nhdrp = &nhdr; nhdrp->sbh_origlen = ntohl(hdrp->sbh_origlen); nhdrp->sbh_msglen = ntohl(hdrp->sbh_msglen); nhdrp->sbh_totlen = ntohl(hdrp->sbh_totlen); nhdrp->sbh_drops = ntohl(hdrp->sbh_drops); nhdrp->sbh_timestamp.tv_sec = ntohl(hdrp->sbh_timestamp.tv_sec); nhdrp->sbh_timestamp.tv_usec = ntohl(hdrp->sbh_timestamp.tv_usec); } /* Enhanced check for valid header */ if ((nhdrp->sbh_totlen == 0) || (bp + nhdrp->sbh_totlen) < bp || (bp + nhdrp->sbh_totlen) > bufstop || (nhdrp->sbh_origlen == 0) || (bp + nhdrp->sbh_origlen) < bp || (nhdrp->sbh_msglen == 0) || (bp + nhdrp->sbh_msglen) < bp || (bp + nhdrp->sbh_msglen) > bufstop || (nhdrp->sbh_msglen > nhdrp->sbh_origlen) || (nhdrp->sbh_totlen < nhdrp->sbh_msglen) || (nhdrp->sbh_timestamp.tv_sec == 0)) { if (cap) (void) fprintf(stderr, "(warning) bad packet " "header in capture file"); else (void) fprintf(stderr, "(warning) bad packet " "header in buffer"); (void) fprintf(stderr, " offset %d: length=%d\n", bp - buf, nhdrp->sbh_totlen); goto err; } if (nhdrp->sbh_totlen > (dlinfo.di_max_sdu + MAX_HDRTRAILER)) { if (cap) (void) fprintf(stderr, "(warning) packet length" " greater than MTU in capture file"); else (void) fprintf(stderr, "(warning) packet length" " greater than MTU in buffer"); (void) fprintf(stderr, " offset %d: length=%d\n", bp - buf, nhdrp->sbh_totlen); } /* * Check for incomplete packet. We are conservative here, * since we don't know how good the checking is in other * parts of the code. We pass a partial packet, with * a warning. */ if (pktp + nhdrp->sbh_msglen > bufstop) { (void) fprintf(stderr, "truncated packet buffer\n"); nhdrp->sbh_msglen = bufstop - pktp; } #ifdef DEBUG if (zflg) corrupt(pktp, pktp + nhdrp->sbh_msglen, buf, bufstop); #endif /* DEBUG */ header_okay = 1; if (!filter || want_packet(pktp, nhdrp->sbh_msglen, nhdrp->sbh_origlen)) { count++; /* * Start deadman timer for interpreter processing */ (void) snoop_alarm(SNOOP_ALARM_GRAN*SNOOP_MAXRECOVER, NULL); encap_levels = 0; if (!cap || count >= first) proc(nhdrp, pktp, count, flags); if (cap && count >= last) { (void) snoop_alarm(0, NULL); break; } if (maxcount && count >= maxcount) { (void) fprintf(stderr, "%d packets captured\n", count); exit(0); } snoop_nrecover = 0; /* success */ (void) snoop_alarm(0, NULL); last_timestamp = hdrp->sbh_timestamp; /* save stamp */ } continue; err: /* * Corruption has been detected. Reset errors. */ snoop_recover(); /* * packet header was apparently okay. Continue. */ if (header_okay) continue; /* * Otherwise try to scan forward to the next packet, using * the last known timestamp if it is available. */ nhdrp = &nhdr; nhdrp->sbh_totlen = 0; if (last_timestamp.tv_sec == 0) { bp += sizeof (int); } else { for (bp += sizeof (int); bp <= bufstop; bp += sizeof (int)) { hdrp = (struct sb_hdr *)bp; /* An approximate timestamp located */ if ((hdrp->sbh_timestamp.tv_sec >> 8) == (last_timestamp.tv_sec >> 8)) break; } } } /* reset jmp_env for program exit */ (void) memcpy((char *)jmp_env, (char *)ojmp_env, sizeof (jmp_env)); proc(0, -1, 0); } /* * Called if nwrite() encounters write problems. */ static void cap_write_error(const char *msgtype) { (void) fprintf(stderr, "snoop: cannot write %s to capture file: %s\n", msgtype, strerror(errno)); exit(1); } /* * Writes target buffer to the open file descriptor. Upon detection of a short * write, an attempt to process the remaining bytes occurs until all anticipated * bytes are written. An error status is returned to indicate any serious write * failures. */ static int nwrite(int fd, const void *buffer, size_t buflen) { size_t nwritten; ssize_t nbytes = 0; const char *buf = buffer; for (nwritten = 0; nwritten < buflen; nwritten += nbytes) { nbytes = write(fd, &buf[nwritten], buflen - nwritten); if (nbytes == -1) return (-1); if (nbytes == 0) { errno = EIO; return (-1); } } return (0); } /* * Routines for opening, closing, reading and writing * a capture file of packets saved with the -o option. */ static int capfile_out; /* * The snoop capture file has a header to identify * it as a capture file and record its version. * A file without this header is assumed to be an * old format snoop file. * * A version 1 header looks like this: * * 0 1 2 3 4 5 6 7 8 9 10 11 * +---+---+---+---+---+---+---+---+---+---+---+---+---+ * | s | n | o | o | p | \0| \0| \0| version | data * +---+---+---+---+---+---+---+---+---+---+---+---+---+ * | word 0 | word 1 | word 2 | * * * A version 2 header adds a word that identifies the MAC type. * This allows for capture files from FDDI etc. * * 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 * +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+ * | s | n | o | o | p | \0| \0| \0| version | MAC type | data * +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+ * | word 0 | word 1 | word 2 | word 3 * */ static const char *snoop_id = "snoop\0\0\0"; static const int snoop_idlen = 8; static const int snoop_version = 2; void cap_open_write(const char *name) { int vers; capfile_out = open(name, O_CREAT | O_TRUNC | O_RDWR, 0666); if (capfile_out < 0) pr_err("%s: %m", name); vers = htonl(snoop_version); if (nwrite(capfile_out, snoop_id, snoop_idlen) == -1) cap_write_error("snoop_id"); if (nwrite(capfile_out, &vers, sizeof (int)) == -1) cap_write_error("version"); } void cap_close(void) { (void) close(capfile_out); } static char *cap_buffp = NULL; static int cap_len = 0; static int cap_new; void cap_open_read(const char *name) { struct stat st; int cap_vers; int *word, device_mac_type; int capfile_in; capfile_in = open(name, O_RDONLY); if (capfile_in < 0) pr_err("couldn't open %s: %m", name); if (fstat(capfile_in, &st) < 0) pr_err("couldn't stat %s: %m", name); cap_len = st.st_size; cap_buffp = mmap(0, cap_len, PROT_READ, MAP_PRIVATE, capfile_in, 0); (void) close(capfile_in); if ((int)cap_buffp == -1) pr_err("couldn't mmap %s: %m", name); /* Check if new snoop capture file format */ cap_new = bcmp(cap_buffp, snoop_id, snoop_idlen) == 0; /* * If new file - check version and * set buffer pointer to point at first packet */ if (cap_new) { cap_vers = ntohl(*(int *)(cap_buffp + snoop_idlen)); cap_buffp += snoop_idlen + sizeof (int); cap_len -= snoop_idlen + sizeof (int); switch (cap_vers) { case 1: device_mac_type = DL_ETHER; break; case 2: device_mac_type = ntohl(*((int *)cap_buffp)); cap_buffp += sizeof (int); cap_len -= sizeof (int); break; default: pr_err("capture file: %s: Version %d unrecognized\n", name, cap_vers); } for (interface = &INTERFACES[0]; interface->mac_type != -1; interface++) if (interface->mac_type == device_mac_type) break; if (interface->mac_type == -1) pr_err("Mac Type = %x is not supported\n", device_mac_type); } else { /* Use heuristic to check if it's an old-style file */ device_mac_type = DL_ETHER; word = (int *)cap_buffp; if (!((word[0] < 1600 && word[1] < 1600) && (word[0] < word[1]) && (word[2] > 610000000 && word[2] < 770000000))) pr_err("not a capture file: %s", name); /* Change protection so's we can fix the headers */ if (mprotect(cap_buffp, cap_len, PROT_READ | PROT_WRITE) < 0) pr_err("mprotect: %s: %m", name); } dlinfo.di_max_sdu = MAXINT; /* Decode any stored packet. */ } void cap_read(int first, int last, int filter, void (*proc)(), int flags) { extern int count; count = 0; scan(cap_buffp, cap_len, filter, 1, !cap_new, proc, first, last, flags); (void) munmap(cap_buffp, cap_len); } /* ARGSUSED */ void cap_write(struct sb_hdr *hdrp, char *pktp, int num, int flags) { int pktlen, mac; static int first = 1; struct sb_hdr nhdr; extern boolean_t qflg; if (hdrp == NULL) return; if (first) { first = 0; mac = htonl(interface->mac_type); if (nwrite(capfile_out, &mac, sizeof (int)) == -1) cap_write_error("mac_type"); } pktlen = hdrp->sbh_totlen - sizeof (*hdrp); /* * Convert sb_hdr to network byte order */ nhdr.sbh_origlen = htonl(hdrp->sbh_origlen); nhdr.sbh_msglen = htonl(hdrp->sbh_msglen); nhdr.sbh_totlen = htonl(hdrp->sbh_totlen); nhdr.sbh_drops = htonl(hdrp->sbh_drops); nhdr.sbh_timestamp.tv_sec = htonl(hdrp->sbh_timestamp.tv_sec); nhdr.sbh_timestamp.tv_usec = htonl(hdrp->sbh_timestamp.tv_usec); if (nwrite(capfile_out, &nhdr, sizeof (nhdr)) == -1) cap_write_error("packet header"); if (nwrite(capfile_out, pktp, pktlen) == -1) cap_write_error("packet"); if (! qflg) show_count(); } /* * Convert a packet header from * old to new format. */ static void convert_old(struct ohdr *ohdrp) { struct sb_hdr nhdr; nhdr.sbh_origlen = ohdrp->o_len; nhdr.sbh_msglen = ohdrp->o_msglen; nhdr.sbh_totlen = ohdrp->o_totlen; nhdr.sbh_drops = ohdrp->o_drops; nhdr.sbh_timestamp = ohdrp->o_time; *(struct sb_hdr *)ohdrp = nhdr; } static int strioctl(int fd, int cmd, int timout, int len, void *dp) { struct strioctl sioc; int rc; sioc.ic_cmd = cmd; sioc.ic_timout = timout; sioc.ic_len = len; sioc.ic_dp = dp; rc = ioctl(fd, I_STR, &sioc); if (rc < 0) return (rc); else return (sioc.ic_len); }