| // SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) |
| // Copyright (c) 2019 Facebook |
| // Copyright (c) 2020 Netflix |
| // |
| // Based on opensnoop(8) from BCC by Brendan Gregg and others. |
| // 14-Feb-2020 Brendan Gregg Created this. |
| #include <argp.h> |
| #include <signal.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <sys/time.h> |
| #include <time.h> |
| #include <unistd.h> |
| #include <bpf/libbpf.h> |
| #include <bpf/bpf.h> |
| #include "opensnoop.h" |
| #include "opensnoop.skel.h" |
| #include "btf_helpers.h" |
| #include "trace_helpers.h" |
| #ifdef USE_BLAZESYM |
| #include "blazesym.h" |
| #endif |
| |
| /* Tune the buffer size and wakeup rate. These settings cope with roughly |
| * 50k opens/sec. |
| */ |
| #define PERF_BUFFER_PAGES 64 |
| #define PERF_BUFFER_TIME_MS 10 |
| |
| /* Set the poll timeout when no events occur. This can affect -d accuracy. */ |
| #define PERF_POLL_TIMEOUT_MS 100 |
| |
| #define NSEC_PER_SEC 1000000000ULL |
| |
| static volatile sig_atomic_t exiting = 0; |
| |
| #ifdef USE_BLAZESYM |
| static blazesym *symbolizer; |
| #endif |
| |
| static struct env { |
| pid_t pid; |
| pid_t tid; |
| uid_t uid; |
| int duration; |
| bool verbose; |
| bool timestamp; |
| bool print_uid; |
| bool extended; |
| bool failed; |
| char *name; |
| #ifdef USE_BLAZESYM |
| bool callers; |
| #endif |
| } env = { |
| .uid = INVALID_UID |
| }; |
| |
| const char *argp_program_version = "opensnoop 0.1"; |
| const char *argp_program_bug_address = |
| "https://github.com/iovisor/bcc/tree/master/libbpf-tools"; |
| const char argp_program_doc[] = |
| "Trace open family syscalls\n" |
| "\n" |
| "USAGE: opensnoop [-h] [-T] [-U] [-x] [-p PID] [-t TID] [-u UID] [-d DURATION]\n" |
| #ifdef USE_BLAZESYM |
| " [-n NAME] [-e] [-c]\n" |
| #else |
| " [-n NAME] [-e]\n" |
| #endif |
| "\n" |
| "EXAMPLES:\n" |
| " ./opensnoop # trace all open() syscalls\n" |
| " ./opensnoop -T # include timestamps\n" |
| " ./opensnoop -U # include UID\n" |
| " ./opensnoop -x # only show failed opens\n" |
| " ./opensnoop -p 181 # only trace PID 181\n" |
| " ./opensnoop -t 123 # only trace TID 123\n" |
| " ./opensnoop -u 1000 # only trace UID 1000\n" |
| " ./opensnoop -d 10 # trace for 10 seconds only\n" |
| " ./opensnoop -n main # only print process names containing \"main\"\n" |
| " ./opensnoop -e # show extended fields\n" |
| #ifdef USE_BLAZESYM |
| " ./opensnoop -c # show calling functions\n" |
| #endif |
| ""; |
| |
| static const struct argp_option opts[] = { |
| { "duration", 'd', "DURATION", 0, "Duration to trace"}, |
| { "extended-fields", 'e', NULL, 0, "Print extended fields"}, |
| { NULL, 'h', NULL, OPTION_HIDDEN, "Show the full help"}, |
| { "name", 'n', "NAME", 0, "Trace process names containing this"}, |
| { "pid", 'p', "PID", 0, "Process ID to trace"}, |
| { "tid", 't', "TID", 0, "Thread ID to trace"}, |
| { "timestamp", 'T', NULL, 0, "Print timestamp"}, |
| { "uid", 'u', "UID", 0, "User ID to trace"}, |
| { "print-uid", 'U', NULL, 0, "Print UID"}, |
| { "verbose", 'v', NULL, 0, "Verbose debug output" }, |
| { "failed", 'x', NULL, 0, "Failed opens only"}, |
| #ifdef USE_BLAZESYM |
| { "callers", 'c', NULL, 0, "Show calling functions"}, |
| #endif |
| {}, |
| }; |
| |
| static error_t parse_arg(int key, char *arg, struct argp_state *state) |
| { |
| static int pos_args; |
| long int pid, uid, duration; |
| |
| switch (key) { |
| case 'e': |
| env.extended = true; |
| break; |
| case 'h': |
| argp_usage(state); |
| break; |
| case 'T': |
| env.timestamp = true; |
| break; |
| case 'U': |
| env.print_uid = true; |
| break; |
| case 'v': |
| env.verbose = true; |
| break; |
| case 'x': |
| env.failed = true; |
| break; |
| case 'd': |
| errno = 0; |
| duration = strtol(arg, NULL, 10); |
| if (errno || duration <= 0) { |
| fprintf(stderr, "Invalid duration: %s\n", arg); |
| argp_usage(state); |
| } |
| env.duration = duration; |
| break; |
| case 'n': |
| errno = 0; |
| env.name = arg; |
| break; |
| case 'p': |
| errno = 0; |
| pid = strtol(arg, NULL, 10); |
| if (errno || pid <= 0) { |
| fprintf(stderr, "Invalid PID: %s\n", arg); |
| argp_usage(state); |
| } |
| env.pid = pid; |
| break; |
| case 't': |
| errno = 0; |
| pid = strtol(arg, NULL, 10); |
| if (errno || pid <= 0) { |
| fprintf(stderr, "Invalid TID: %s\n", arg); |
| argp_usage(state); |
| } |
| env.tid = pid; |
| break; |
| case 'u': |
| errno = 0; |
| uid = strtol(arg, NULL, 10); |
| if (errno || uid < 0 || uid >= INVALID_UID) { |
| fprintf(stderr, "Invalid UID %s\n", arg); |
| argp_usage(state); |
| } |
| env.uid = uid; |
| break; |
| #ifdef USE_BLAZESYM |
| case 'c': |
| env.callers = true; |
| break; |
| #endif |
| case ARGP_KEY_ARG: |
| if (pos_args++) { |
| fprintf(stderr, |
| "Unrecognized positional argument: %s\n", arg); |
| argp_usage(state); |
| } |
| errno = 0; |
| 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; |
| } |
| |
| void handle_event(void *ctx, int cpu, void *data, __u32 data_sz) |
| { |
| const struct event *e = data; |
| struct tm *tm; |
| #ifdef USE_BLAZESYM |
| sym_src_cfg cfgs[] = { |
| { .src_type = SRC_T_PROCESS, .params = { .process = { .pid = e->pid }}}, |
| }; |
| const blazesym_result *result = NULL; |
| const blazesym_csym *sym; |
| int i, j; |
| #endif |
| int sps_cnt; |
| char ts[32]; |
| time_t t; |
| int fd, err; |
| |
| /* name filtering is currently done in user space */ |
| if (env.name && strstr(e->comm, env.name) == NULL) |
| return; |
| |
| /* prepare fields */ |
| time(&t); |
| tm = localtime(&t); |
| strftime(ts, sizeof(ts), "%H:%M:%S", tm); |
| if (e->ret >= 0) { |
| fd = e->ret; |
| err = 0; |
| } else { |
| fd = -1; |
| err = - e->ret; |
| } |
| |
| #ifdef USE_BLAZESYM |
| if (env.callers) |
| result = blazesym_symbolize(symbolizer, cfgs, 1, (const uint64_t *)&e->callers, 2); |
| #endif |
| |
| /* print output */ |
| sps_cnt = 0; |
| if (env.timestamp) { |
| printf("%-8s ", ts); |
| sps_cnt += 9; |
| } |
| if (env.print_uid) { |
| printf("%-7d ", e->uid); |
| sps_cnt += 8; |
| } |
| printf("%-6d %-16s %3d %3d ", e->pid, e->comm, fd, err); |
| sps_cnt += 7 + 17 + 4 + 4; |
| if (env.extended) { |
| printf("%08o ", e->flags); |
| sps_cnt += 9; |
| } |
| printf("%s\n", e->fname); |
| |
| #ifdef USE_BLAZESYM |
| for (i = 0; result && i < result->size; i++) { |
| if (result->entries[i].size == 0) |
| continue; |
| sym = &result->entries[i].syms[0]; |
| |
| for (j = 0; j < sps_cnt; j++) |
| printf(" "); |
| if (sym->line_no) |
| printf("%s:%ld\n", sym->symbol, sym->line_no); |
| else |
| printf("%s\n", sym->symbol); |
| } |
| |
| blazesym_result_free(result); |
| #endif |
| } |
| |
| void handle_lost_events(void *ctx, int cpu, __u64 lost_cnt) |
| { |
| fprintf(stderr, "Lost %llu events on CPU #%d!\n", lost_cnt, cpu); |
| } |
| |
| 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, |
| }; |
| struct perf_buffer *pb = NULL; |
| struct opensnoop_bpf *obj; |
| __u64 time_end = 0; |
| 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 = opensnoop_bpf__open_opts(&open_opts); |
| if (!obj) { |
| fprintf(stderr, "failed to open BPF object\n"); |
| return 1; |
| } |
| |
| /* initialize global data (filtering options) */ |
| obj->rodata->targ_tgid = env.pid; |
| obj->rodata->targ_pid = env.tid; |
| obj->rodata->targ_uid = env.uid; |
| obj->rodata->targ_failed = env.failed; |
| |
| /* aarch64 and riscv64 don't have open syscall */ |
| if (!tracepoint_exists("syscalls", "sys_enter_open")) { |
| bpf_program__set_autoload(obj->progs.tracepoint__syscalls__sys_enter_open, false); |
| bpf_program__set_autoload(obj->progs.tracepoint__syscalls__sys_exit_open, false); |
| } |
| |
| err = opensnoop_bpf__load(obj); |
| if (err) { |
| fprintf(stderr, "failed to load BPF object: %d\n", err); |
| goto cleanup; |
| } |
| |
| err = opensnoop_bpf__attach(obj); |
| if (err) { |
| fprintf(stderr, "failed to attach BPF programs\n"); |
| goto cleanup; |
| } |
| |
| #ifdef USE_BLAZESYM |
| if (env.callers) |
| symbolizer = blazesym_new(); |
| #endif |
| |
| /* print headers */ |
| if (env.timestamp) |
| printf("%-8s ", "TIME"); |
| if (env.print_uid) |
| printf("%-7s ", "UID"); |
| printf("%-6s %-16s %3s %3s ", "PID", "COMM", "FD", "ERR"); |
| if (env.extended) |
| printf("%-8s ", "FLAGS"); |
| printf("%s", "PATH"); |
| #ifdef USE_BLAZESYM |
| if (env.callers) |
| printf("/CALLER"); |
| #endif |
| printf("\n"); |
| |
| /* setup event callbacks */ |
| pb = perf_buffer__new(bpf_map__fd(obj->maps.events), PERF_BUFFER_PAGES, |
| handle_event, handle_lost_events, NULL, NULL); |
| if (!pb) { |
| err = -errno; |
| fprintf(stderr, "failed to open perf buffer: %d\n", err); |
| goto cleanup; |
| } |
| |
| /* setup duration */ |
| if (env.duration) |
| time_end = get_ktime_ns() + env.duration * NSEC_PER_SEC; |
| |
| if (signal(SIGINT, sig_int) == SIG_ERR) { |
| fprintf(stderr, "can't set signal handler: %s\n", strerror(errno)); |
| err = 1; |
| goto cleanup; |
| } |
| |
| /* main: poll */ |
| while (!exiting) { |
| err = perf_buffer__poll(pb, PERF_POLL_TIMEOUT_MS); |
| if (err < 0 && err != -EINTR) { |
| fprintf(stderr, "error polling perf buffer: %s\n", strerror(-err)); |
| goto cleanup; |
| } |
| if (env.duration && get_ktime_ns() > time_end) |
| goto cleanup; |
| /* reset err to return 0 if exiting */ |
| err = 0; |
| } |
| |
| cleanup: |
| perf_buffer__free(pb); |
| opensnoop_bpf__destroy(obj); |
| cleanup_core_btf(&open_opts); |
| #ifdef USE_BLAZESYM |
| blazesym_free(symbolizer); |
| #endif |
| |
| return err != 0; |
| } |