| // SPDX-License-Identifier: GPL-2.0 |
| // Copyright (c) 2022 Microsoft Corporation |
| // |
| // Based on tcptracer(8) from BCC by Kinvolk GmbH and |
| // tcpconnect(8) by Anton Protopopov |
| #include <sys/resource.h> |
| #include <arpa/inet.h> |
| #include <argp.h> |
| #include <signal.h> |
| #include <limits.h> |
| #include <unistd.h> |
| #include <time.h> |
| #include <bpf/bpf.h> |
| #include "tcptracer.h" |
| #include "tcptracer.skel.h" |
| #include "btf_helpers.h" |
| #include "trace_helpers.h" |
| #include "map_helpers.h" |
| |
| #define warn(...) fprintf(stderr, __VA_ARGS__) |
| |
| static volatile sig_atomic_t exiting = 0; |
| |
| const char *argp_program_version = "tcptracer 0.1"; |
| const char *argp_program_bug_address = |
| "https://github.com/iovisor/bcc/tree/master/libbpf-tools"; |
| static const char argp_program_doc[] = |
| "\ntcptracer: Trace TCP connections\n" |
| "\n" |
| "EXAMPLES:\n" |
| " tcptracer # trace all TCP connections\n" |
| " tcptracer -t # include timestamps\n" |
| " tcptracer -p 181 # only trace PID 181\n" |
| " tcptracer -U # include UID\n" |
| " tcptracer -u 1000 # only trace UID 1000\n" |
| " tcptracer --C mappath # only trace cgroups in the map\n" |
| " tcptracer --M mappath # only trace mount namespaces in the map\n" |
| ; |
| |
| static int get_int(const char *arg, int *ret, int min, int max) |
| { |
| char *end; |
| long val; |
| |
| errno = 0; |
| val = strtol(arg, &end, 10); |
| if (errno) { |
| warn("strtol: %s: %s\n", arg, strerror(errno)); |
| return -1; |
| } else if (end == arg || val < min || val > max) { |
| return -1; |
| } |
| if (ret) |
| *ret = val; |
| return 0; |
| } |
| |
| static int get_uint(const char *arg, unsigned int *ret, |
| unsigned int min, unsigned int max) |
| { |
| char *end; |
| long val; |
| |
| errno = 0; |
| val = strtoul(arg, &end, 10); |
| if (errno) { |
| warn("strtoul: %s: %s\n", arg, strerror(errno)); |
| return -1; |
| } else if (end == arg || val < min || val > max) { |
| return -1; |
| } |
| if (ret) |
| *ret = val; |
| return 0; |
| } |
| |
| static const struct argp_option opts[] = { |
| { "verbose", 'v', NULL, 0, "Verbose debug output" }, |
| { "timestamp", 't', NULL, 0, "Include timestamp on output" }, |
| { "print-uid", 'U', NULL, 0, "Include UID on output" }, |
| { "pid", 'p', "PID", 0, "Process PID to trace" }, |
| { "uid", 'u', "UID", 0, "Process UID to trace" }, |
| { "cgroupmap", 'C', "PATH", 0, "trace cgroups in this map" }, |
| { "mntnsmap", 'M', "PATH", 0, "trace mount namespaces in this map" }, |
| { NULL, 'h', NULL, OPTION_HIDDEN, "Show the full help" }, |
| {}, |
| }; |
| |
| static struct env { |
| bool verbose; |
| bool count; |
| bool print_timestamp; |
| bool print_uid; |
| pid_t pid; |
| uid_t uid; |
| } env = { |
| .uid = (uid_t) -1, |
| }; |
| |
| static error_t parse_arg(int key, char *arg, struct argp_state *state) |
| { |
| int err; |
| |
| switch (key) { |
| case 'h': |
| argp_state_help(state, stderr, ARGP_HELP_STD_HELP); |
| break; |
| case 'v': |
| env.verbose = true; |
| break; |
| case 'c': |
| env.count = true; |
| break; |
| case 't': |
| env.print_timestamp = true; |
| break; |
| case 'U': |
| env.print_uid = true; |
| break; |
| case 'p': |
| err = get_int(arg, &env.pid, 1, INT_MAX); |
| if (err) { |
| warn("invalid PID: %s\n", arg); |
| argp_usage(state); |
| } |
| break; |
| case 'u': |
| err = get_uint(arg, &env.uid, 0, (uid_t) -2); |
| if (err) { |
| warn("invalid UID: %s\n", arg); |
| argp_usage(state); |
| } |
| break; |
| case 'C': |
| warn("not implemented: --cgroupmap"); |
| break; |
| case 'M': |
| warn("not implemented: --mntnsmap"); |
| break; |
| default: |
| return ARGP_ERR_UNKNOWN; |
| } |
| return 0; |
| } |
| |
| static int libbpf_print_fn(enum libbpf_print_level level, const char *format, va_list args) |
| { |
| if (level == LIBBPF_DEBUG && !env.verbose) |
| return 0; |
| return vfprintf(stderr, format, args); |
| } |
| |
| static void sig_int(int signo) |
| { |
| exiting = 1; |
| } |
| |
| static void print_events_header() |
| { |
| if (env.print_timestamp) |
| printf("%-9s", "TIME(s)"); |
| if (env.print_uid) |
| printf("%-6s", "UID"); |
| printf("%s %-6s %-12s %-2s %-16s %-16s %-4s %-4s\n", |
| "T", "PID", "COMM", "IP", "SADDR", "DADDR", "SPORT", "DPORT"); |
| } |
| |
| static void handle_event(void *ctx, int cpu, void *data, __u32 data_sz) |
| { |
| const struct event *event = data; |
| char src[INET6_ADDRSTRLEN]; |
| char dst[INET6_ADDRSTRLEN]; |
| union { |
| struct in_addr x4; |
| struct in6_addr x6; |
| } s, d; |
| static __u64 start_ts; |
| |
| if (event->af == AF_INET) { |
| s.x4.s_addr = event->saddr_v4; |
| d.x4.s_addr = event->daddr_v4; |
| } else if (event->af == AF_INET6) { |
| memcpy(&s.x6.s6_addr, &event->saddr_v6, sizeof(s.x6.s6_addr)); |
| memcpy(&d.x6.s6_addr, &event->daddr_v6, sizeof(d.x6.s6_addr)); |
| } else { |
| warn("broken event: event->af=%d", event->af); |
| return; |
| } |
| |
| if (env.print_timestamp) { |
| if (start_ts == 0) |
| start_ts = event->ts_us; |
| printf("%-9.3f", (event->ts_us - start_ts) / 1000000.0); |
| } |
| |
| if (env.print_uid) |
| printf("%-6d", event->uid); |
| |
| char type = '-'; |
| switch (event->type) { |
| case TCP_EVENT_TYPE_CONNECT: |
| type = 'C'; |
| break; |
| case TCP_EVENT_TYPE_ACCEPT: |
| type = 'A'; |
| break; |
| case TCP_EVENT_TYPE_CLOSE: |
| type = 'X'; |
| break; |
| } |
| |
| printf("%c %-6d %-12.12s %-2d %-16s %-16s %-4d %-4d\n", |
| type, event->pid, event->task, |
| event->af == AF_INET ? 4 : 6, |
| inet_ntop(event->af, &s, src, sizeof(src)), |
| inet_ntop(event->af, &d, dst, sizeof(dst)), |
| ntohs(event->sport), ntohs(event->dport)); |
| } |
| |
| static void handle_lost_events(void *ctx, int cpu, __u64 lost_cnt) |
| { |
| warn("Lost %llu events on CPU #%d!\n", lost_cnt, cpu); |
| } |
| |
| static void print_events(int perf_map_fd) |
| { |
| struct perf_buffer *pb; |
| int err; |
| |
| pb = perf_buffer__new(perf_map_fd, 128, |
| handle_event, handle_lost_events, NULL, NULL); |
| if (!pb) { |
| err = -errno; |
| warn("failed to open perf buffer: %d\n", err); |
| goto cleanup; |
| } |
| |
| print_events_header(); |
| while (!exiting) { |
| err = perf_buffer__poll(pb, 100); |
| if (err < 0 && err != -EINTR) { |
| warn("error polling perf buffer: %s\n", strerror(-err)); |
| goto cleanup; |
| } |
| /* reset err to return 0 if exiting */ |
| err = 0; |
| } |
| |
| cleanup: |
| perf_buffer__free(pb); |
| } |
| |
| int main(int argc, char **argv) |
| { |
| LIBBPF_OPTS(bpf_object_open_opts, open_opts); |
| static const struct argp argp = { |
| .options = opts, |
| .parser = parse_arg, |
| .doc = argp_program_doc, |
| .args_doc = NULL, |
| }; |
| struct tcptracer_bpf *obj; |
| int err; |
| |
| err = argp_parse(&argp, argc, argv, 0, NULL, NULL); |
| if (err) |
| return err; |
| |
| libbpf_set_print(libbpf_print_fn); |
| |
| err = ensure_core_btf(&open_opts); |
| if (err) { |
| fprintf(stderr, "failed to fetch necessary BTF for CO-RE: %s\n", strerror(-err)); |
| return 1; |
| } |
| |
| obj = tcptracer_bpf__open_opts(&open_opts); |
| if (!obj) { |
| warn("failed to open BPF object\n"); |
| return 1; |
| } |
| |
| if (env.pid) |
| obj->rodata->filter_pid = env.pid; |
| if (env.uid != (uid_t) -1) |
| obj->rodata->filter_uid = env.uid; |
| |
| err = tcptracer_bpf__load(obj); |
| if (err) { |
| warn("failed to load BPF object: %d\n", err); |
| goto cleanup; |
| } |
| |
| err = tcptracer_bpf__attach(obj); |
| if (err) { |
| warn("failed to attach BPF programs: %s\n", strerror(-err)); |
| goto cleanup; |
| } |
| |
| if (signal(SIGINT, sig_int) == SIG_ERR) { |
| warn("can't set signal handler: %s\n", strerror(errno)); |
| err = 1; |
| goto cleanup; |
| } |
| |
| |
| print_events(bpf_map__fd(obj->maps.events)); |
| |
| cleanup: |
| tcptracer_bpf__destroy(obj); |
| cleanup_core_btf(&open_opts); |
| |
| return err != 0; |
| } |