From e2bbf175a2184bd76f6c54ccf8456babeb1a46fc Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Tue, 9 Apr 2024 15:16:35 +0200 Subject: Adding upstream version 9.1. Signed-off-by: Daniel Baumann --- pimd/mtracebis.c | 577 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 577 insertions(+) create mode 100644 pimd/mtracebis.c (limited to 'pimd/mtracebis.c') diff --git a/pimd/mtracebis.c b/pimd/mtracebis.c new file mode 100644 index 0000000..9c3f1a7 --- /dev/null +++ b/pimd/mtracebis.c @@ -0,0 +1,577 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Multicast Traceroute for FRRouting + * Copyright (C) 2018 Mladen Sablic + */ + +#include + +#ifdef __linux__ + +#include "pim_igmp_mtrace.h" + +#include "checksum.h" +#include "prefix.h" +#include "mtracebis_routeget.h" +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define MTRACEBIS_VERSION "0.1" +#define MTRACE_TIMEOUT (5) + +#define IP_HDR_LEN (sizeof(struct ip)) +#define IP_RA_LEN (4) +#define MTRACE_BUF_LEN (MTRACE_HDR_SIZE + (MTRACE_MAX_HOPS * MTRACE_RSP_SIZE)) +#define IP_AND_MTRACE_BUF_LEN (IP_HDR_LEN + IP_RA_LEN + MTRACE_BUF_LEN) + +static const char *progname; +static void usage(void) +{ + fprintf(stderr, "Usage : %s []\n", + progname); +} +static void version(void) +{ + fprintf(stderr, "%s %s\n", progname, MTRACEBIS_VERSION); +} + +static void print_host(struct in_addr addr) +{ + struct hostent *h; + char buf[PREFIX_STRLEN]; + + h = gethostbyaddr(&addr, sizeof(addr), AF_INET); + if (h == NULL) + printf("?"); + else + printf("%s", h->h_name); + printf(" (%s) ", inet_ntop(AF_INET, &addr, buf, sizeof(buf))); +} + +static void print_line_no(int i) +{ + printf("%3d ", -i); +} + +static const char *rtg_proto_str(enum mtrace_rtg_proto proto) +{ + static char buf[80]; + + buf[0] = '\0'; + + switch (proto) { + case MTRACE_RTG_PROTO_DVMRP: + return "DVMRP"; + case MTRACE_RTG_PROTO_MOSPF: + return "MOSPF"; + case MTRACE_RTG_PROTO_PIM: + return "PIM"; + case MTRACE_RTG_PROTO_CBT: + return "CBT"; + case MTRACE_RTG_PROTO_PIM_SPECIAL: + return "PIM special"; + case MTRACE_RTG_PROTO_PIM_STATIC: + return "PIM static"; + case MTRACE_RTG_PROTO_DVMRP_STATIC: + return "DVMRP static"; + case MTRACE_RTG_PROTO_PIM_MBGP: + return "PIM MBGP"; + case MTRACE_RTG_PROTO_CBT_SPECIAL: + return "CBT special"; + case MTRACE_RTG_PROTO_CBT_STATIC: + return "CBT static"; + case MTRACE_RTG_PROTO_PIM_ASSERT: + return "PIM assert"; + default: + snprintf(buf, sizeof(buf), "unknown protocol (%d)", proto); + return buf; + } +} + +static void print_rtg_proto(uint32_t rtg_proto) +{ + printf("%s", rtg_proto_str(rtg_proto)); +} + +static void print_fwd_ttl(uint32_t fwd_ttl) +{ + printf("thresh^ %d", fwd_ttl); +} + +static const char *fwd_code_str(enum mtrace_fwd_code code) +{ + static char buf[80]; + + buf[0] = '\0'; + + switch (code) { + case MTRACE_FWD_CODE_NO_ERROR: + return "no error"; + case MTRACE_FWD_CODE_WRONG_IF: + return "wrong interface"; + case MTRACE_FWD_CODE_PRUNE_SENT: + return "prune sent"; + case MTRACE_FWD_CODE_PRUNE_RCVD: + return "prune received"; + case MTRACE_FWD_CODE_SCOPED: + return "scoped"; + case MTRACE_FWD_CODE_NO_ROUTE: + return "no route"; + case MTRACE_FWD_CODE_WRONG_LAST_HOP: + return "wrong last hop"; + case MTRACE_FWD_CODE_NOT_FORWARDING: + return "not forwarding"; + case MTRACE_FWD_CODE_REACHED_RP: + return "reached RP"; + case MTRACE_FWD_CODE_RPF_IF: + return "RPF interface"; + case MTRACE_FWD_CODE_NO_MULTICAST: + return "no multicast"; + case MTRACE_FWD_CODE_INFO_HIDDEN: + return "info hidden"; + case MTRACE_FWD_CODE_NO_SPACE: + return "no space"; + case MTRACE_FWD_CODE_OLD_ROUTER: + return "old router"; + case MTRACE_FWD_CODE_ADMIN_PROHIB: + return "admin. prohib."; + default: + snprintf(buf, sizeof(buf), "unknown fwd. code (%d)", code); + return buf; + } +} + +static void print_fwd_code(uint32_t fwd_code) +{ + printf("%s", fwd_code_str(fwd_code)); +} + +static void print_rsp(struct igmp_mtrace_rsp *rsp) +{ + print_host(rsp->outgoing); + if (rsp->fwd_code == 0 || rsp->fwd_code == MTRACE_FWD_CODE_REACHED_RP) { + print_rtg_proto(rsp->rtg_proto); + printf(" "); + if (rsp->fwd_code == MTRACE_FWD_CODE_REACHED_RP) + printf("(RP) "); + if (rsp->rtg_proto == MTRACE_RTG_PROTO_PIM) { + switch (rsp->src_mask) { + case MTRACE_SRC_MASK_GROUP: + printf("(*,G) "); + break; + case MTRACE_SRC_MASK_SOURCE: + printf("(S,G) "); + break; + } + } + print_fwd_ttl(rsp->fwd_ttl); + } else { + print_fwd_code(rsp->fwd_code); + } + printf("\n"); +} + +static void print_dest(struct igmp_mtrace *mtrace) +{ + print_line_no(0); + print_host(mtrace->dst_addr); + printf("\n"); +} + +static void print_summary(struct igmp_mtrace *mtrace, int hops, long msec) +{ + int i; + int t = 0; + + for (i = 0; i < hops; i++) + t += mtrace->rsp[i].fwd_ttl; + + printf("Round trip time %ld ms; total ttl of %d required.\n", msec, t); +} + +static void print_responses(struct igmp_mtrace *mtrace, int hops, long msec) +{ + int i; + + print_dest(mtrace); + + for (i = 0; i < hops; i++) { + print_line_no(i + 1); + print_rsp(&mtrace->rsp[i]); + } + print_summary(mtrace, hops, msec); +} + +static int send_query(int fd, struct in_addr to_addr, + struct igmp_mtrace *mtrace) +{ + struct sockaddr_in to; + socklen_t tolen; + int sent; + + memset(&to, 0, sizeof(to)); + to.sin_family = AF_INET; + to.sin_addr = to_addr; + tolen = sizeof(to); + + sent = sendto(fd, (char *)mtrace, sizeof(*mtrace), MSG_DONTWAIT, + (struct sockaddr *)&to, tolen); + + if (sent < 1) + return -1; + return 0; +} + +static void print_query(struct igmp_mtrace *mtrace) +{ + char src_str[INET_ADDRSTRLEN]; + char dst_str[INET_ADDRSTRLEN]; + char grp_str[INET_ADDRSTRLEN]; + + printf("* Mtrace from %s to %s via group %s\n", + inet_ntop(AF_INET, &mtrace->src_addr, src_str, sizeof(src_str)), + inet_ntop(AF_INET, &mtrace->dst_addr, dst_str, sizeof(dst_str)), + inet_ntop(AF_INET, &mtrace->grp_addr, grp_str, sizeof(grp_str))); +} + +static int recv_response(int fd, int *hops, struct igmp_mtrace *mtracer) +{ + int recvd; + char mtrace_buf[IP_AND_MTRACE_BUF_LEN]; + struct ip *ip; + struct igmp_mtrace *mtrace; + int mtrace_len; + int responses; + unsigned short sum; + size_t mtrace_off; + size_t ip_len; + + recvd = recvfrom(fd, mtrace_buf, IP_AND_MTRACE_BUF_LEN, 0, NULL, 0); + + if (recvd < 1) { + fprintf(stderr, "recvfrom error: %s\n", strerror(errno)); + return -1; + } + + if (recvd < (int)sizeof(struct ip)) { + fprintf(stderr, "no ip header\n"); + return -1; + } + + ip = (struct ip *)mtrace_buf; + + if (ip->ip_v != 4) { + fprintf(stderr, "IP not version 4\n"); + return -1; + } + + sum = ip->ip_sum; + ip->ip_sum = 0; + + if (sum != in_cksum(ip, ip->ip_hl * 4)) + return -1; + + /* Header overflow check */ + mtrace_off = 4 * ip->ip_hl; + if (mtrace_off > MTRACE_BUF_LEN) + return -1; + + /* Underflow/overflow check */ + ip_len = ntohs(ip->ip_len); + if (ip_len < mtrace_off || ip_len < MTRACE_HDR_SIZE + || ip_len > MTRACE_BUF_LEN) + return -1; + + mtrace_len = ip_len - mtrace_off; + mtrace = (struct igmp_mtrace *)(mtrace_buf + mtrace_off); + + sum = mtrace->checksum; + mtrace->checksum = 0; + if (sum != in_cksum(mtrace, mtrace_len)) { + fprintf(stderr, "mtrace checksum wrong\n"); + return -1; + } + + if (mtrace->type != PIM_IGMP_MTRACE_RESPONSE) + return -1; + + + responses = mtrace_len - sizeof(struct igmp_mtrace); + responses /= sizeof(struct igmp_mtrace_rsp); + + if (responses > MTRACE_MAX_HOPS) { + fprintf(stderr, "mtrace too large\n"); + return -1; + } + + if (hops) + *hops = responses; + + if (mtracer) + memcpy(mtracer, mtrace, mtrace_len); + + return 0; +} + +static int wait_for_response(int fd, int *hops, struct igmp_mtrace *mtrace, + long *ret_msec) +{ + fd_set readfds; + struct timeval timeout; + int ret; + long msec, rmsec, tmsec; + + FD_ZERO(&readfds); + FD_SET(fd, &readfds); + + memset(&timeout, 0, sizeof(timeout)); + + timeout.tv_sec = MTRACE_TIMEOUT; + + tmsec = timeout.tv_sec * 1000 + timeout.tv_usec / 1000; + do { + ret = select(fd + 1, &readfds, NULL, NULL, &timeout); + if (ret <= 0) + return ret; + rmsec = timeout.tv_sec * 1000 + timeout.tv_usec / 1000; + msec = tmsec - rmsec; + } while (recv_response(fd, hops, mtrace) != 0); + + if (ret_msec) + *ret_msec = msec; + + return ret; +} + +static bool check_end(struct igmp_mtrace *mtrace, int hops) +{ + return mtrace->src_addr.s_addr == mtrace->rsp[hops - 1].prev_hop.s_addr; +} + +int main(int argc, char *const argv[]) +{ + struct in_addr mc_source; + struct in_addr mc_group; + struct in_addr iface_addr; + struct in_addr gw_addr; + struct in_addr mtrace_addr; + struct igmp_mtrace mtrace; + struct igmp_mtrace *mtracep; + int hops = 255; + int rhops; + int maxhops = 255; + int perhop = 3; + int ifindex; + int unicast = 1; + int ttl = 64; + int fd = -1; + int ret = -1; + int c; + long msec; + int i, j; + char ifname[IF_NAMESIZE]; + char mbuf[MTRACE_BUF_LEN]; + bool not_group; + + mtrace_addr.s_addr = inet_addr("224.0.1.32"); + + uid_t uid = getuid(); + + if (uid != 0) { + printf("must run as root\n"); + exit(EXIT_FAILURE); + } + + if (argc <= 0) + progname = "mtracebis"; + else + progname = argv[0]; + + if (argc != 2 && argc != 3) { + usage(); + exit(EXIT_FAILURE); + } + + while (1) { + static struct option long_options[] = { + {"help", no_argument, 0, 'h'}, + {"version", no_argument, 0, 'v'}, + {0, 0, 0, 0}}; + int option_index = 0; + + c = getopt_long(argc, argv, "vh", long_options, &option_index); + + if (c == -1) + break; + + switch (c) { + case 'h': + usage(); + exit(0); + case 'v': + version(); + exit(0); + default: + usage(); + exit(EXIT_FAILURE); + } + } + if (inet_pton(AF_INET, argv[1], &mc_source) != 1) { + usage(); + fprintf(stderr, "%s: %s is not a valid IPv4 address\n", argv[0], + argv[1]); + exit(EXIT_FAILURE); + } + + mc_group.s_addr = INADDR_ANY; + not_group = false; + + if (argc == 3) { + if (inet_pton(AF_INET, argv[2], &mc_group) != 1) + not_group = true; + if (!not_group && !IPV4_CLASS_DE(ntohl(mc_group.s_addr))) + not_group = true; + } + + if (not_group) { + usage(); + fprintf(stderr, "%s: %s is not a valid IPv4 group address\n", + argv[0], argv[2]); + exit(EXIT_FAILURE); + } + + ifindex = routeget(mc_source, &iface_addr, &gw_addr); + if (ifindex < 0) { + fprintf(stderr, "%s: failed to get route to source %s\n", + argv[0], argv[1]); + exit(EXIT_FAILURE); + } + + if (if_indextoname(ifindex, ifname) == NULL) { + fprintf(stderr, "%s: if_indextoname error: %s\n", argv[0], + strerror(errno)); + exit(EXIT_FAILURE); + } + + /* zero mtrace struct */ + memset((char *)&mtrace, 0, sizeof(mtrace)); + + /* set up query */ + mtrace.type = PIM_IGMP_MTRACE_QUERY_REQUEST; + mtrace.hops = hops; + mtrace.checksum = 0; + mtrace.grp_addr = mc_group; + mtrace.src_addr = mc_source; + mtrace.dst_addr = iface_addr; + mtrace.rsp_addr = unicast ? iface_addr : mtrace_addr; + mtrace.rsp_ttl = ttl; + mtrace.qry_id = 0xffffff & time(NULL); + + mtrace.checksum = in_cksum(&mtrace, sizeof(mtrace)); + + fd = socket(AF_INET, SOCK_RAW, IPPROTO_IGMP); + + if (fd < 1) { + fprintf(stderr, "%s: socket error: %s\n", argv[0], + strerror(errno)); + exit(EXIT_FAILURE); + } + + ret = setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, ifname, + strlen(ifname)); + + if (ret < 0) { + fprintf(stderr, "%s: setsockopt error: %s\n", argv[0], + strerror(errno)); + ret = EXIT_FAILURE; + goto close_fd; + } + + print_query(&mtrace); + if (send_query(fd, gw_addr, &mtrace) < 0) { + fprintf(stderr, "%s: sendto error: %s\n", argv[0], + strerror(errno)); + ret = EXIT_FAILURE; + goto close_fd; + } + printf("Querying full reverse path...\n"); + mtracep = (struct igmp_mtrace *)mbuf; + ret = wait_for_response(fd, &rhops, mtracep, &msec); + if (ret > 0) { + print_responses(mtracep, rhops, msec); + ret = 0; + goto close_fd; + } + if (ret < 0) { + fprintf(stderr, "%s: select error: %s\n", argv[0], + strerror(errno)); + ret = EXIT_FAILURE; + goto close_fd; + } + printf(" * "); + printf("switching to hop-by-hop:\n"); + print_dest(&mtrace); + for (i = 1; i < maxhops; i++) { + print_line_no(i); + mtrace.hops = i; + for (j = 0; j < perhop; j++) { + mtrace.qry_id++; + mtrace.checksum = 0; + mtrace.checksum = in_cksum(&mtrace, sizeof(mtrace)); + if (send_query(fd, gw_addr, &mtrace) < 0) { + fprintf(stderr, "%s: sendto error: %s\n", + argv[0], strerror(errno)); + ret = EXIT_FAILURE; + goto close_fd; + } + ret = wait_for_response(fd, &rhops, mtracep, &msec); + if (ret > 0) { + if (check_end(mtracep, rhops)) { + print_rsp(&mtracep->rsp[rhops - 1]); + print_summary(mtracep, rhops, msec); + ret = 0; + goto close_fd; + } + if (i > rhops) { + printf(" * ...giving up.\n"); + ret = 0; + goto close_fd; + } + print_rsp(&mtracep->rsp[rhops - 1]); + break; + } + printf(" *"); + } + if (ret <= 0) + printf("\n"); + } + ret = 0; +close_fd: + close(fd); + exit(ret); +} + +#else /* __linux__ */ + +#include +#include + +int main(int argc, char *argv[]) +{ + printf("%s implemented only for GNU/Linux\n", argv[0]); + exit(0); +} + +#endif /* __linux__ */ -- cgit v1.2.3