wpa_cli.c

一个Linux下无线网卡的设置工具

static int wpa_cli_exec(const char *program, const char *arg1,
			const char *arg2)
{
	char *cmd;
	size_t len;

	len = strlen(program) + strlen(arg1) + strlen(arg2) + 3;
	cmd = malloc(len);
	if (cmd == NULL)
		return -1;
	snprintf(cmd, len, "%s %s %s", program, arg1, arg2);
	system(cmd);
	free(cmd);

	return 0;
}


static void wpa_cli_action_process(const char *msg)
{
	const char *pos;

	pos = msg;
	if (*pos == '<') {
		/* skip priority */
		pos = strchr(pos, '>');
		if (pos)
			pos++;
		else
			pos = msg;
	}

	if (str_match(pos, WPA_EVENT_CONNECTED)) {
		wpa_cli_exec(action_file, ctrl_ifname, "CONNECTED");
	} else if (str_match(pos, WPA_EVENT_DISCONNECTED)) {
		wpa_cli_exec(action_file, ctrl_ifname, "DISCONNECTED");
	} else if (str_match(pos, WPA_EVENT_TERMINATING)) {
		printf("wpa_supplicant is terminating - stop monitoring\n");
		wpa_cli_quit = 1;
	}
}


static void wpa_cli_action_cb(char *msg, size_t len)
{
	wpa_cli_action_process(msg);
}


static void wpa_cli_recv_pending(struct wpa_ctrl *ctrl, int in_read,
				 int action_monitor)
{
	int first = 1;
	if (ctrl_conn == NULL)
		return;
	while (wpa_ctrl_pending(ctrl)) {
		char buf[256];
		size_t len = sizeof(buf) - 1;
		if (wpa_ctrl_recv(ctrl, buf, &len) == 0) {
			buf[len] = '\0';
			if (action_monitor)
				wpa_cli_action_process(buf);
			else {
				if (in_read && first)
					printf("\n");
				first = 0;
				printf("%s\n", buf);
			}
		} else {
			printf("Could not read pending message.\n");
			break;
		}
	}
}


#ifdef CONFIG_READLINE
static char * wpa_cli_cmd_gen(const char *text, int state)
{
	static int i, len;
	const char *cmd;

	if (state == 0) {
		i = 0;
		len = strlen(text);
	}

	while ((cmd = wpa_cli_commands[i].cmd)) {
		i++;
		if (strncasecmp(cmd, text, len) == 0)
			return strdup(cmd);
	}

	return NULL;
}


static char * wpa_cli_dummy_gen(const char *text, int state)
{
	return NULL;
}


static char ** wpa_cli_completion(const char *text, int start, int end)
{
	return rl_completion_matches(text, start == 0 ?
				     wpa_cli_cmd_gen : wpa_cli_dummy_gen);
}
#endif /* CONFIG_READLINE */


static void wpa_cli_interactive(void)
{
#define max_args 10
	char cmdbuf[256], *cmd, *argv[max_args], *pos;
	int argc;
#ifdef CONFIG_READLINE
	char *home, *hfile = NULL;
#endif /* CONFIG_READLINE */

	printf("\nInteractive mode\n\n");

#ifdef CONFIG_READLINE
	rl_attempted_completion_function = wpa_cli_completion;
	home = getenv("HOME");
	if (home) {
		const char *fname = ".wpa_cli_history";
		int hfile_len = strlen(home) + 1 + strlen(fname) + 1;
		hfile = malloc(hfile_len);
		if (hfile) {
			snprintf(hfile, hfile_len, "%s/%s", home, fname);
			read_history(hfile);
			stifle_history(100);
		}
	}
#endif /* CONFIG_READLINE */

	do {
		wpa_cli_recv_pending(ctrl_conn, 0, 0);
#ifndef CONFIG_NATIVE_WINDOWS
		alarm(1);
#endif /* CONFIG_NATIVE_WINDOWS */
#ifdef CONFIG_READLINE
		cmd = readline("> ");
		if (cmd && *cmd) {
			HIST_ENTRY *h;
			while (next_history())
				;
			h = previous_history();
			if (h == NULL || strcmp(cmd, h->line) != 0)
				add_history(cmd);
			next_history();
		}
#else /* CONFIG_READLINE */
		printf("> ");
		cmd = fgets(cmdbuf, sizeof(cmdbuf), stdin);
#endif /* CONFIG_READLINE */
#ifndef CONFIG_NATIVE_WINDOWS
		alarm(0);
#endif /* CONFIG_NATIVE_WINDOWS */
		if (cmd == NULL)
			break;
		pos = cmd;
		while (*pos != '\0') {
			if (*pos == '\n') {
				*pos = '\0';
				break;
			}
			pos++;
		}
		argc = 0;
		pos = cmd;
		for (;;) {
			while (*pos == ' ')
				pos++;
			if (*pos == '\0')
				break;
			argv[argc] = pos;
			argc++;
			if (argc == max_args)
				break;
			if (*pos == '"') {
				char *pos2 = strrchr(pos, '"');
				if (pos2)
					pos = pos2 + 1;
			}
			while (*pos != '\0' && *pos != ' ')
				pos++;
			if (*pos == ' ')
				*pos++ = '\0';
		}
		if (argc)
			wpa_request(ctrl_conn, argc, argv);

		if (cmd != cmdbuf)
			free(cmd);
	} while (!wpa_cli_quit);

#ifdef CONFIG_READLINE
	if (hfile) {
		/* Save command history, excluding lines that may contain
		 * passwords. */
		HIST_ENTRY *h;
		history_set_pos(0);
		h = next_history();
		while (h) {
			char *p = h->line;
			while (*p == ' ' || *p == '\t')
				p++;
			if (strncasecmp(p, "pa", 2) == 0 ||
			    strncasecmp(p, "o", 1) == 0 ||
			    strncasecmp(p, "n", 1)) {
				h = remove_history(where_history());
				if (h) {
					free(h->line);
					free(h->data);
					free(h);
				}
				h = current_history();
			} else {
				h = next_history();
			}
		}
		write_history(hfile);
		free(hfile);
	}
#endif /* CONFIG_READLINE */
}


static void wpa_cli_action(struct wpa_ctrl *ctrl)
{
	fd_set rfds;
	int fd, res;
	struct timeval tv;
	char buf[16];
	size_t len;

	fd = wpa_ctrl_get_fd(ctrl);

	while (!wpa_cli_quit) {
		FD_ZERO(&rfds);
		FD_SET(fd, &rfds);
		tv.tv_sec = 2;
		tv.tv_usec = 0;
		res = select(fd + 1, &rfds, NULL, NULL, &tv);
		if (res < 0 && errno != EINTR) {
			perror("select");
			break;
		}

		if (FD_ISSET(fd, &rfds))
			wpa_cli_recv_pending(ctrl, 0, 1);
		else {
			/* verify that connection is still working */
			len = sizeof(buf) - 1;
			if (wpa_ctrl_request(ctrl, "PING", 4, buf, &len,
					     wpa_cli_action_cb) < 0 ||
			    len < 4 || memcmp(buf, "PONG", 4) != 0) {
				printf("wpa_supplicant did not reply to PING "
				       "command - exiting\n");
				break;
			}
		}
	}
}


static void wpa_cli_cleanup(void)
{
	wpa_cli_close_connection();
	if (pid_file)
		unlink(pid_file);

#ifdef CONFIG_NATIVE_WINDOWS
	WSACleanup();
#endif /* CONFIG_NATIVE_WINDOWS */
}

static void wpa_cli_terminate(int sig)
{
	wpa_cli_cleanup();
	exit(0);
}


#ifndef CONFIG_NATIVE_WINDOWS
static void wpa_cli_alarm(int sig)
{
	if (ctrl_conn && _wpa_ctrl_command(ctrl_conn, "PING", 0)) {
		printf("Connection to wpa_supplicant lost - trying to "
		       "reconnect\n");
		wpa_cli_close_connection();
	}
	if (!ctrl_conn) {
		ctrl_conn = wpa_cli_open_connection(ctrl_ifname);
		if (ctrl_conn) {
			printf("Connection to wpa_supplicant "
			       "re-established\n");
			if (wpa_ctrl_attach(ctrl_conn) == 0) {
				wpa_cli_attached = 1;
			} else {
				printf("Warning: Failed to attach to "
				       "wpa_supplicant.\n");
			}
		}
	}
	if (ctrl_conn)
		wpa_cli_recv_pending(ctrl_conn, 1, 0);
	alarm(1);
}
#endif /* CONFIG_NATIVE_WINDOWS */


int main(int argc, char *argv[])
{
	int interactive;
	int warning_displayed = 0;
	int c;
	int daemonize = 0;
	FILE *f;
	const char *global = NULL;

#ifdef CONFIG_NATIVE_WINDOWS
	WSADATA wsaData;
	if (WSAStartup(MAKEWORD(2, 0), &wsaData)) {
		printf("Could not find a usable WinSock.dll\n");
		return -1;
	}
#endif /* CONFIG_NATIVE_WINDOWS */

	for (;;) {
		c = getopt(argc, argv, "a:Bg:hi:p:P:v");
		if (c < 0)
			break;
		switch (c) {
		case 'a':
			action_file = optarg;
			break;
		case 'B':
			daemonize = 1;
			break;
		case 'g':
			global = optarg;
			break;
		case 'h':
			usage();
			return 0;
		case 'v':
			printf("%s\n", wpa_cli_version);
			return 0;
		case 'i':
			ctrl_ifname = strdup(optarg);
			break;
		case 'p':
			ctrl_iface_dir = optarg;
			break;
		case 'P':
			pid_file = optarg;
			break;
		default:
			usage();
			return -1;
		}
	}

	interactive = (argc == optind) && (action_file == NULL);

	if (interactive)
		printf("%s\n\n%s\n\n", wpa_cli_version, wpa_cli_license);

	if (global) {
		ctrl_conn = wpa_ctrl_open(global);
		if (ctrl_conn == NULL) {
			perror("Failed to connect to wpa_supplicant - "
			       "wpa_ctrl_open");
			return -1;
		}
	}

	for (; !global;) {
		if (ctrl_ifname == NULL) {
			struct dirent *dent;
			DIR *dir = opendir(ctrl_iface_dir);
			if (dir) {
				while ((dent = readdir(dir))) {
					if (strcmp(dent->d_name, ".") == 0 ||
					    strcmp(dent->d_name, "..") == 0)
						continue;
					printf("Selected interface '%s'\n",
					       dent->d_name);
					ctrl_ifname = strdup(dent->d_name);
					break;
				}
				closedir(dir);
			}
		}
		ctrl_conn = wpa_cli_open_connection(ctrl_ifname);
		if (ctrl_conn) {
			if (warning_displayed)
				printf("Connection established.\n");
			break;
		}

		if (!interactive) {
			perror("Failed to connect to wpa_supplicant - "
			       "wpa_ctrl_open");
			return -1;
		}

		if (!warning_displayed) {
			printf("Could not connect to wpa_supplicant - "
			       "re-trying\n");
			warning_displayed = 1;
		}
		sleep(1);
		continue;
	}

	signal(SIGINT, wpa_cli_terminate);
	signal(SIGTERM, wpa_cli_terminate);
#ifndef CONFIG_NATIVE_WINDOWS
	signal(SIGALRM, wpa_cli_alarm);
#endif /* CONFIG_NATIVE_WINDOWS */

	if (interactive || action_file) {
		if (wpa_ctrl_attach(ctrl_conn) == 0) {
			wpa_cli_attached = 1;
		} else {
			printf("Warning: Failed to attach to "
			       "wpa_supplicant.\n");
			if (!interactive)
				return -1;
		}
	}

	if (daemonize && daemon(0, 0)) {
		perror("daemon");
		return -1;
	}

	if (pid_file) {
		f = fopen(pid_file, "w");
		if (f) {
			fprintf(f, "%u\n", getpid());
			fclose(f);
		}
	}

	if (interactive)
		wpa_cli_interactive();
	else if (action_file)
		wpa_cli_action(ctrl_conn);
	else
		wpa_request(ctrl_conn, argc - optind, &argv[optind]);

	free(ctrl_ifname);
	wpa_cli_cleanup();

	return 0;
}