libbpf-tools/bindsnoop.c - platform/external/bcc - Git at Google

 /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */

 /*
  * Copyright (c) 2021 Hengqi Chen
  *
  * Based on bindsnoop(8) from BCC by Pavel Dubovitsky.
  * 11-May-2021   Hengqi Chen   Created this.
  */
 #include <argp.h>
 #include <arpa/inet.h>
 #include <errno.h>
 #include <signal.h>
 #include <string.h>
 #include <sys/socket.h>
 #include <time.h>
 #include <unistd.h>
 #include <fcntl.h>

 #include <bpf/libbpf.h>
 #include <bpf/bpf.h>
 #include "bindsnoop.h"
 #include "bindsnoop.skel.h"
 #include "trace_helpers.h"
 #include "btf_helpers.h"

 #define PERF_BUFFER_PAGES	16
 #define PERF_POLL_TIMEOUT_MS	100
 #define warn(...) fprintf(stderr, __VA_ARGS__)

 static struct env {
 	char	*cgroupspath;
 	bool	cg;
 } env;

 static volatile sig_atomic_t exiting = 0;

 static bool emit_timestamp = false;
 static pid_t target_pid = 0;
 static bool ignore_errors = true;
 static char *target_ports = NULL;
 static bool verbose = false;

 const char *argp_program_version = "bindsnoop 0.1";
 const char *argp_program_bug_address =
 	"https://github.com/iovisor/bcc/tree/master/libbpf-tools";
 const char argp_program_doc[] =
 "Trace bind syscalls.\n"
 "\n"
 "USAGE: bindsnoop [-h] [-t] [-x] [-p PID] [-P ports] [-c CG]\n"
 "\n"
 "EXAMPLES:\n"
 "    bindsnoop             # trace all bind syscall\n"
 "    bindsnoop -t          # include timestamps\n"
 "    bindsnoop -x          # include errors on output\n"
 "    bindsnoop -p 1216     # only trace PID 1216\n"
 "    bindsnoop -c CG       # Trace process under cgroupsPath CG\n"
 "    bindsnoop -P 80,81    # only trace port 80 and 81\n"
 "\n"
 "Socket options are reported as:\n"
 "  SOL_IP     IP_FREEBIND              F....\n"
 "  SOL_IP     IP_TRANSPARENT           .T...\n"
 "  SOL_IP     IP_BIND_ADDRESS_NO_PORT  ..N..\n"
 "  SOL_SOCKET SO_REUSEADDR             ...R.\n"
 "  SOL_SOCKET SO_REUSEPORT             ....r\n";

 static const struct argp_option opts[] = {
 	{ "timestamp", 't', NULL, 0, "Include timestamp on output" },
 	{ "cgroup", 'c', "/sys/fs/cgroup/unified", 0, "Trace process in cgroup path" },
 	{ "failed", 'x', NULL, 0, "Include errors on output." },
 	{ "pid", 'p', "PID", 0, "Process ID to trace" },
 	{ "ports", 'P', "PORTS", 0, "Comma-separated list of ports to trace." },
 	{ "verbose", 'v', NULL, 0, "Verbose debug output" },
 	{ NULL, 'h', NULL, OPTION_HIDDEN, "Show the full help" },
 	{},
 };

 static error_t parse_arg(int key, char *arg, struct argp_state *state)
 {
 	long pid, port_num;
 	char *port;

 	switch (key) {
 	case 'p':
 		errno = 0;
 		pid = strtol(arg, NULL, 10);
 		if (errno || pid <= 0) {
 			warn("Invalid PID: %s\n", arg);
 			argp_usage(state);
 		}
 		target_pid = pid;
 		break;
 	case 'c':
 		env.cgroupspath = arg;
 		env.cg = true;
 		break;
 	case 'P':
 		if (!arg) {
 			warn("No ports specified\n");
 			argp_usage(state);
 		}
 		target_ports = strdup(arg);
 		port = strtok(arg, ",");
 		while (port) {
 			port_num = strtol(port, NULL, 10);
 			if (errno || port_num <= 0 || port_num > 65536) {
 				warn("Invalid ports: %s\n", arg);
 				argp_usage(state);
 			}
 			port = strtok(NULL, ",");
 		}
 		break;
 	case 'x':
 		ignore_errors = false;
 		break;
 	case 't':
 		emit_timestamp = true;
 		break;
 	case 'v':
 		verbose = true;
 		break;
 	case 'h':
 		argp_state_help(state, stderr, ARGP_HELP_STD_HELP);
 		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 && !verbose)
 		return 0;
 	return vfprintf(stderr, format, args);
 }

 static void sig_int(int signo)
 {
 	exiting = 1;
 }

 static void handle_event(void *ctx, int cpu, void *data, __u32 data_sz)
 {
 	struct bind_event *e = data;
 	time_t t;
 	struct tm *tm;
 	char ts[32], addr[48];
 	char opts[] = {'F', 'T', 'N', 'R', 'r', '\0'};
 	const char *proto;
 	int i = 0;

 	if (emit_timestamp) {
 		time(&t);
 		tm = localtime(&t);
 		strftime(ts, sizeof(ts), "%H:%M:%S", tm);
 		printf("%8s ", ts);
 	}
 	if (e->proto == IPPROTO_TCP)
 		proto = "TCP";
 	else if (e->proto == IPPROTO_UDP)
 		proto = "UDP";
 	else
 		proto = "UNK";
 	while (opts[i]) {
 		if (!((1 << i) & e->opts)) {
 			opts[i] = '.';
 		}
 		i++;
 	}
 	if (e->ver == 4) {
 		inet_ntop(AF_INET, &e->addr, addr, sizeof(addr));
 	} else {
 		inet_ntop(AF_INET6, &e->addr, addr, sizeof(addr));
 	}
 	printf("%-7d %-16s %-3d %-5s %-5s %-4d %-5d %-48s\n",
 	       e->pid, e->task, e->ret, proto, opts, e->bound_dev_if, e->port, addr);
 }

 static void handle_lost_events(void *ctx, int cpu, __u64 lost_cnt)
 {
 	warn("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 bindsnoop_bpf *obj;
 	int err, port_map_fd;
 	char *port;
 	short port_num;
 	int idx, cg_map_fd;
 	int cgfd = -1;

 	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 = bindsnoop_bpf__open_opts(&open_opts);
 	if (!obj) {
 		warn("failed to open BPF object\n");
 		return 1;
 	}

 	obj->rodata->filter_cg = env.cg;
 	obj->rodata->target_pid = target_pid;
 	obj->rodata->ignore_errors = ignore_errors;
 	obj->rodata->filter_by_port = target_ports != NULL;

 	err = bindsnoop_bpf__load(obj);
 	if (err) {
 		warn("failed to load BPF object: %d\n", err);
 		goto cleanup;
 	}

 	/* update cgroup path fd to map */
 	if (env.cg) {
 		idx = 0;
 		cg_map_fd = bpf_map__fd(obj->maps.cgroup_map);
 		cgfd = open(env.cgroupspath, O_RDONLY);
 		if (cgfd < 0) {
 			fprintf(stderr, "Failed opening Cgroup path: %s", env.cgroupspath);
 			goto cleanup;
 		}
 		if (bpf_map_update_elem(cg_map_fd, &idx, &cgfd, BPF_ANY)) {
 			fprintf(stderr, "Failed adding target cgroup to map");
 			goto cleanup;
 		}
 	}

 	if (target_ports) {
 		port_map_fd = bpf_map__fd(obj->maps.ports);
 		port = strtok(target_ports, ",");
 		while (port) {
 			port_num = strtol(port, NULL, 10);
 			bpf_map_update_elem(port_map_fd, &port_num, &port_num, BPF_ANY);
 			port = strtok(NULL, ",");
 		}
 	}

 	err = bindsnoop_bpf__attach(obj);
 	if (err) {
 		warn("failed to attach BPF programs: %d\n", err);
 		goto cleanup;
 	}

 	pb = perf_buffer__new(bpf_map__fd(obj->maps.events), PERF_BUFFER_PAGES,
 			      handle_event, handle_lost_events, NULL, NULL);
 	if (!pb) {
 		err = -errno;
 		warn("failed to open perf buffer: %d\n", err);
 		goto cleanup;
 	}

 	if (signal(SIGINT, sig_int) == SIG_ERR) {
 		warn("can't set signal handler: %s\n", strerror(errno));
 		err = 1;
 		goto cleanup;
 	}

 	if (emit_timestamp)
 		printf("%-8s ", "TIME(s)");
 	printf("%-7s %-16s %-3s %-5s %-5s %-4s %-5s %-48s\n",
 	       "PID", "COMM", "RET", "PROTO", "OPTS", "IF", "PORT", "ADDR");

 	while (!exiting) {
 		err = perf_buffer__poll(pb, PERF_POLL_TIMEOUT_MS);
 		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);
 	bindsnoop_bpf__destroy(obj);
 	cleanup_core_btf(&open_opts);
 	if (cgfd > 0)
 		close(cgfd);

 	return err != 0;
 }
	/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */

	/*
	* Copyright (c) 2021 Hengqi Chen
	*
	* Based on bindsnoop(8) from BCC by Pavel Dubovitsky.
	* 11-May-2021 Hengqi Chen Created this.
	*/
	#include <argp.h>
	#include <arpa/inet.h>
	#include <errno.h>
	#include <signal.h>
	#include <string.h>
	#include <sys/socket.h>
	#include <time.h>
	#include <unistd.h>
	#include <fcntl.h>

	#include <bpf/libbpf.h>
	#include <bpf/bpf.h>
	#include "bindsnoop.h"
	#include "bindsnoop.skel.h"
	#include "trace_helpers.h"
	#include "btf_helpers.h"

	#define PERF_BUFFER_PAGES 16
	#define PERF_POLL_TIMEOUT_MS 100
	#define warn(...) fprintf(stderr, __VA_ARGS__)

	static struct env {
	char *cgroupspath;
	bool cg;
	} env;

	static volatile sig_atomic_t exiting = 0;

	static bool emit_timestamp = false;
	static pid_t target_pid = 0;
	static bool ignore_errors = true;
	static char *target_ports = NULL;
	static bool verbose = false;

	const char *argp_program_version = "bindsnoop 0.1";
	const char *argp_program_bug_address =
	"https://github.com/iovisor/bcc/tree/master/libbpf-tools";
	const char argp_program_doc[] =
	"Trace bind syscalls.\n"
	"\n"
	"USAGE: bindsnoop [-h] [-t] [-x] [-p PID] [-P ports] [-c CG]\n"
	"\n"
	"EXAMPLES:\n"
	" bindsnoop # trace all bind syscall\n"
	" bindsnoop -t # include timestamps\n"
	" bindsnoop -x # include errors on output\n"
	" bindsnoop -p 1216 # only trace PID 1216\n"
	" bindsnoop -c CG # Trace process under cgroupsPath CG\n"
	" bindsnoop -P 80,81 # only trace port 80 and 81\n"
	"\n"
	"Socket options are reported as:\n"
	" SOL_IP IP_FREEBIND F....\n"
	" SOL_IP IP_TRANSPARENT .T...\n"
	" SOL_IP IP_BIND_ADDRESS_NO_PORT ..N..\n"
	" SOL_SOCKET SO_REUSEADDR ...R.\n"
	" SOL_SOCKET SO_REUSEPORT ....r\n";

	static const struct argp_option opts[] = {
	{ "timestamp", 't', NULL, 0, "Include timestamp on output" },
	{ "cgroup", 'c', "/sys/fs/cgroup/unified", 0, "Trace process in cgroup path" },
	{ "failed", 'x', NULL, 0, "Include errors on output." },
	{ "pid", 'p', "PID", 0, "Process ID to trace" },
	{ "ports", 'P', "PORTS", 0, "Comma-separated list of ports to trace." },
	{ "verbose", 'v', NULL, 0, "Verbose debug output" },
	{ NULL, 'h', NULL, OPTION_HIDDEN, "Show the full help" },
	{},
	};

	static error_t parse_arg(int key, char arg, struct argp_state state)
	{
	long pid, port_num;
	char *port;

	switch (key) {
	case 'p':
	errno = 0;
	pid = strtol(arg, NULL, 10);
	if (errno \|\| pid <= 0) {
	warn("Invalid PID: %s\n", arg);
	argp_usage(state);
	}
	target_pid = pid;
	break;
	case 'c':
	env.cgroupspath = arg;
	env.cg = true;
	break;
	case 'P':
	if (!arg) {
	warn("No ports specified\n");
	argp_usage(state);
	}
	target_ports = strdup(arg);
	port = strtok(arg, ",");
	while (port) {
	port_num = strtol(port, NULL, 10);
	if (errno \|\| port_num <= 0 \|\| port_num > 65536) {
	warn("Invalid ports: %s\n", arg);
	argp_usage(state);
	}
	port = strtok(NULL, ",");
	}
	break;
	case 'x':
	ignore_errors = false;
	break;
	case 't':
	emit_timestamp = true;
	break;
	case 'v':
	verbose = true;
	break;
	case 'h':
	argp_state_help(state, stderr, ARGP_HELP_STD_HELP);
	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 && !verbose)
	return 0;
	return vfprintf(stderr, format, args);
	}

	static void sig_int(int signo)
	{
	exiting = 1;
	}

	static void handle_event(void ctx, int cpu, void data, __u32 data_sz)
	{
	struct bind_event *e = data;
	time_t t;
	struct tm *tm;
	char ts[32], addr[48];
	char opts[] = {'F', 'T', 'N', 'R', 'r', '\0'};
	const char *proto;
	int i = 0;

	if (emit_timestamp) {
	time(&t);
	tm = localtime(&t);
	strftime(ts, sizeof(ts), "%H:%M:%S", tm);
	printf("%8s ", ts);
	}
	if (e->proto == IPPROTO_TCP)
	proto = "TCP";
	else if (e->proto == IPPROTO_UDP)
	proto = "UDP";
	else
	proto = "UNK";
	while (opts[i]) {
	if (!((1 << i) & e->opts)) {
	opts[i] = '.';
	}
	i++;
	}
	if (e->ver == 4) {
	inet_ntop(AF_INET, &e->addr, addr, sizeof(addr));
	} else {
	inet_ntop(AF_INET6, &e->addr, addr, sizeof(addr));
	}
	printf("%-7d %-16s %-3d %-5s %-5s %-4d %-5d %-48s\n",
	e->pid, e->task, e->ret, proto, opts, e->bound_dev_if, e->port, addr);
	}

	static void handle_lost_events(void *ctx, int cpu, __u64 lost_cnt)
	{
	warn("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 bindsnoop_bpf *obj;
	int err, port_map_fd;
	char *port;
	short port_num;
	int idx, cg_map_fd;
	int cgfd = -1;

	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 = bindsnoop_bpf__open_opts(&open_opts);
	if (!obj) {
	warn("failed to open BPF object\n");
	return 1;
	}

	obj->rodata->filter_cg = env.cg;
	obj->rodata->target_pid = target_pid;
	obj->rodata->ignore_errors = ignore_errors;
	obj->rodata->filter_by_port = target_ports != NULL;

	err = bindsnoop_bpf__load(obj);
	if (err) {
	warn("failed to load BPF object: %d\n", err);
	goto cleanup;
	}

	/* update cgroup path fd to map */
	if (env.cg) {
	idx = 0;
	cg_map_fd = bpf_map__fd(obj->maps.cgroup_map);
	cgfd = open(env.cgroupspath, O_RDONLY);
	if (cgfd < 0) {
	fprintf(stderr, "Failed opening Cgroup path: %s", env.cgroupspath);
	goto cleanup;
	}
	if (bpf_map_update_elem(cg_map_fd, &idx, &cgfd, BPF_ANY)) {
	fprintf(stderr, "Failed adding target cgroup to map");
	goto cleanup;
	}
	}

	if (target_ports) {
	port_map_fd = bpf_map__fd(obj->maps.ports);
	port = strtok(target_ports, ",");
	while (port) {
	port_num = strtol(port, NULL, 10);
	bpf_map_update_elem(port_map_fd, &port_num, &port_num, BPF_ANY);
	port = strtok(NULL, ",");
	}
	}

	err = bindsnoop_bpf__attach(obj);
	if (err) {
	warn("failed to attach BPF programs: %d\n", err);
	goto cleanup;
	}

	pb = perf_buffer__new(bpf_map__fd(obj->maps.events), PERF_BUFFER_PAGES,
	handle_event, handle_lost_events, NULL, NULL);
	if (!pb) {
	err = -errno;
	warn("failed to open perf buffer: %d\n", err);
	goto cleanup;
	}

	if (signal(SIGINT, sig_int) == SIG_ERR) {
	warn("can't set signal handler: %s\n", strerror(errno));
	err = 1;
	goto cleanup;
	}

	if (emit_timestamp)
	printf("%-8s ", "TIME(s)");
	printf("%-7s %-16s %-3s %-5s %-5s %-4s %-5s %-48s\n",
	"PID", "COMM", "RET", "PROTO", "OPTS", "IF", "PORT", "ADDR");

	while (!exiting) {
	err = perf_buffer__poll(pb, PERF_POLL_TIMEOUT_MS);
	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);
	bindsnoop_bpf__destroy(obj);
	cleanup_core_btf(&open_opts);
	if (cgfd > 0)
	close(cgfd);

	return err != 0;
	}