1 /*
2  * Copyright (c) 2022 Stefan Sperling <stsp@openbsd.org>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include <sys/queue.h>
18 #include <sys/socket.h>
19 #include <sys/un.h>
20 
21 #include <err.h>
22 #include <event.h>
23 #include <imsg.h>
24 #include <limits.h>
25 #include <locale.h>
26 #include <sha1.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <string.h>
30 #include <getopt.h>
31 #include <unistd.h>
32 
33 #include "got_error.h"
34 #include "got_version.h"
35 
36 #include "got_lib_gitproto.h"
37 
38 #include "gotd.h"
39 
40 #ifndef nitems
41 #define nitems(_a)	(sizeof((_a)) / sizeof((_a)[0]))
42 #endif
43 
44 #define GOTCTL_CMD_INFO "info"
45 #define GOTCTL_CMD_STOP "stop"
46 
47 struct gotctl_cmd {
48 	const char	*cmd_name;
49 	const struct got_error *(*cmd_main)(int, char *[], int);
50 	void		(*cmd_usage)(void);
51 };
52 
53 __dead static void	usage(int, int);
54 
55 __dead static void	usage_info(void);
56 __dead static void	usage_stop(void);
57 
58 static const struct got_error*		cmd_info(int, char *[], int);
59 static const struct got_error*		cmd_stop(int, char *[], int);
60 
61 static const struct gotctl_cmd gotctl_commands[] = {
62 	{ "info",	cmd_info,	usage_info },
63 	{ "stop",	cmd_stop,	usage_stop },
64 };
65 
66 __dead static void
67 usage_info(void)
68 {
69 	fprintf(stderr, "usage: %s info\n", getprogname());
70 	exit(1);
71 }
72 
73 static const struct got_error *
74 show_info(struct imsg *imsg)
75 {
76 	struct gotd_imsg_info info;
77 	size_t datalen;
78 
79 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
80 	if (datalen != sizeof(info))
81 		return got_error(GOT_ERR_PRIVSEP_LEN);
82 	memcpy(&info, imsg->data, sizeof(info));
83 
84 	printf("gotd PID: %d\n", info.pid);
85 	printf("verbosity: %d\n", info.verbosity);
86 	printf("number of repositories: %d\n", info.nrepos);
87 	printf("number of connected clients: %d\n", info.nclients);
88 	return NULL;
89 }
90 
91 static const struct got_error *
92 show_repo_info(struct imsg *imsg)
93 {
94 	struct gotd_imsg_info_repo info;
95 	size_t datalen;
96 
97 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
98 	if (datalen != sizeof(info))
99 		return got_error(GOT_ERR_PRIVSEP_LEN);
100 	memcpy(&info, imsg->data, sizeof(info));
101 
102 	printf("repository \"%s\", path %s\n", info.repo_name, info.repo_path);
103 	return NULL;
104 }
105 
106 static const char *
107 get_state_name(enum gotd_client_state state)
108 {
109 	static char unknown_state[64];
110 
111 	switch (state) {
112 	case GOTD_STATE_EXPECT_LIST_REFS:
113 		return "list-refs";
114 	case GOTD_STATE_EXPECT_CAPABILITIES:
115 		return "expect-capabilities";
116 	case GOTD_STATE_EXPECT_WANT:
117 		return "expect-want";
118 	case GOTD_STATE_EXPECT_REF_UPDATE:
119 		return "expect-ref-update";
120 	case GOTD_STATE_EXPECT_MORE_REF_UPDATES:
121 		return "expect-more-ref-updates";
122 	case GOTD_STATE_EXPECT_HAVE:
123 		return "expect-have";
124 	case GOTD_STATE_EXPECT_PACKFILE:
125 		return "expect-packfile";
126 	case GOTD_STATE_EXPECT_DONE:
127 		return "expect-done";
128 	case GOTD_STATE_DONE:
129 		return "done";
130 	}
131 
132 	snprintf(unknown_state, sizeof(unknown_state),
133 	    "unknown state %d", state);
134 	return unknown_state;
135 }
136 
137 static const struct got_error *
138 show_client_info(struct imsg *imsg)
139 {
140 	struct gotd_imsg_info_client info;
141 	size_t datalen;
142 
143 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
144 	if (datalen != sizeof(info))
145 		return got_error(GOT_ERR_PRIVSEP_LEN);
146 	memcpy(&info, imsg->data, sizeof(info));
147 
148 	printf("client UID %d, GID %d, protocol state '%s', ",
149 	    info.euid, info.egid, get_state_name(info.state));
150 	if (info.session_child_pid)
151 		printf("session PID %ld, ", (long)info.session_child_pid);
152 	if (info.repo_child_pid)
153 		printf("repo PID %ld, ", (long)info.repo_child_pid);
154 	if (info.is_writing)
155 		printf("writing to %s\n", info.repo_name);
156 	else
157 		printf("reading from %s\n", info.repo_name);
158 
159 	return NULL;
160 }
161 
162 static const struct got_error *
163 show_capability(struct imsg *imsg)
164 {
165 	struct gotd_imsg_capability icapa;
166 	size_t datalen;
167 	char *key, *value = NULL;
168 
169 	memset(&icapa, 0, sizeof(icapa));
170 
171 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
172 	if (datalen < sizeof(icapa))
173 		return got_error(GOT_ERR_PRIVSEP_LEN);
174 	memcpy(&icapa, imsg->data, sizeof(icapa));
175 
176 	if (datalen != sizeof(icapa) + icapa.key_len + icapa.value_len)
177 		return got_error(GOT_ERR_PRIVSEP_LEN);
178 
179 	key = malloc(icapa.key_len + 1);
180 	if (key == NULL)
181 		return got_error_from_errno("malloc");
182 	if (icapa.value_len > 0) {
183 		value = malloc(icapa.value_len + 1);
184 		if (value == NULL) {
185 			free(key);
186 			return got_error_from_errno("malloc");
187 		}
188 	}
189 
190 	memcpy(key, imsg->data + sizeof(icapa), icapa.key_len);
191 	key[icapa.key_len] = '\0';
192 	if (value) {
193 		memcpy(value, imsg->data + sizeof(icapa) + icapa.key_len,
194 		    icapa.value_len);
195 		value[icapa.value_len] = '\0';
196 	}
197 
198 	if (strcmp(key, GOT_CAPA_AGENT) == 0)
199 		printf("  client user agent: %s\n", value);
200 	else if (value)
201 		printf("  client supports %s=%s\n", key, value);
202 	else
203 		printf("  client supports %s\n", key);
204 
205 	free(key);
206 	free(value);
207 	return NULL;
208 }
209 
210 static const struct got_error *
211 cmd_info(int argc, char *argv[], int gotd_sock)
212 {
213 	const struct got_error *err;
214 	struct imsgbuf ibuf;
215 	struct imsg imsg;
216 
217 	imsg_init(&ibuf, gotd_sock);
218 
219 	if (imsg_compose(&ibuf, GOTD_IMSG_INFO, 0, 0, -1, NULL, 0) == -1)
220 		return got_error_from_errno("imsg_compose INFO");
221 
222 	err = gotd_imsg_flush(&ibuf);
223 	while (err == NULL) {
224 		err = gotd_imsg_poll_recv(&imsg, &ibuf, 0);
225 		if (err) {
226 			if (err->code == GOT_ERR_EOF)
227 				err = NULL;
228 			break;
229 		}
230 		
231 		switch (imsg.hdr.type) {
232 		case GOTD_IMSG_ERROR:
233 			err = gotd_imsg_recv_error(NULL, &imsg);
234 			break;
235 		case GOTD_IMSG_INFO:
236 			err = show_info(&imsg);
237 			break;
238 		case GOTD_IMSG_INFO_REPO:
239 			err = show_repo_info(&imsg);
240 			break;
241 		case GOTD_IMSG_INFO_CLIENT:
242 			err = show_client_info(&imsg);
243 			break;
244 		case GOTD_IMSG_CAPABILITY:
245 			err = show_capability(&imsg);
246 			break;
247 		default:
248 			err = got_error(GOT_ERR_PRIVSEP_MSG);
249 			break;
250 		}
251 
252 		imsg_free(&imsg);
253 	}
254 
255 	imsg_clear(&ibuf);
256 	return err;
257 }
258 
259 __dead static void
260 usage_stop(void)
261 {
262 	fprintf(stderr, "usage: %s stop\n", getprogname());
263 	exit(1);
264 }
265 
266 static const struct got_error *
267 cmd_stop(int argc, char *argv[], int gotd_sock)
268 {
269 	const struct got_error *err;
270 	struct imsgbuf ibuf;
271 	struct imsg imsg;
272 
273 	imsg_init(&ibuf, gotd_sock);
274 
275 	if (imsg_compose(&ibuf, GOTD_IMSG_STOP, 0, 0, -1, NULL, 0) == -1)
276 		return got_error_from_errno("imsg_compose STOP");
277 
278 	err = gotd_imsg_flush(&ibuf);
279 	while (err == NULL) {
280 		err = gotd_imsg_poll_recv(&imsg, &ibuf, 0);
281 		if (err) {
282 			if (err->code == GOT_ERR_EOF)
283 				err = NULL;
284 			break;
285 		}
286 		
287 		switch (imsg.hdr.type) {
288 		case GOTD_IMSG_ERROR:
289 			err = gotd_imsg_recv_error(NULL, &imsg);
290 			break;
291 		default:
292 			err = got_error(GOT_ERR_PRIVSEP_MSG);
293 			break;
294 		}
295 
296 		imsg_free(&imsg);
297 	}
298 
299 	imsg_clear(&ibuf);
300 	return err;
301 }
302 
303 static void
304 list_commands(FILE *fp)
305 {
306 	size_t i;
307 
308 	fprintf(fp, "commands:");
309 	for (i = 0; i < nitems(gotctl_commands); i++) {
310 		const struct gotctl_cmd *cmd = &gotctl_commands[i];
311 		fprintf(fp, " %s", cmd->cmd_name);
312 	}
313 	fputc('\n', fp);
314 }
315 
316 __dead static void
317 usage(int hflag, int status)
318 {
319 	FILE *fp = (status == 0) ? stdout : stderr;
320 
321 	fprintf(fp, "usage: %s [-hV] [-f path] command [arg ...]\n",
322 	    getprogname());
323 	if (hflag)
324 		list_commands(fp);
325 	exit(status);
326 }
327 
328 static const struct got_error *
329 apply_unveil(const char *unix_socket_path)
330 {
331 #ifdef PROFILE
332 	if (unveil("gmon.out", "rwc") != 0)
333 		return got_error_from_errno2("unveil", "gmon.out");
334 #endif
335 	if (unveil(unix_socket_path, "w") != 0)
336 		return got_error_from_errno2("unveil", unix_socket_path);
337 
338 	if (unveil(NULL, NULL) != 0)
339 		return got_error_from_errno("unveil");
340 
341 	return NULL;
342 }
343 
344 static int
345 connect_gotd(const char *socket_path)
346 {
347 	const struct got_error *error = NULL;
348 	int gotd_sock = -1;
349 	struct sockaddr_un sun;
350 
351 	error = apply_unveil(socket_path);
352 	if (error)
353 		errx(1, "%s", error->msg);
354 
355 #ifndef PROFILE
356 	if (pledge("stdio unix", NULL) == -1)
357 		err(1, "pledge");
358 #endif
359 	if ((gotd_sock = socket(AF_UNIX, SOCK_STREAM, 0)) == -1)
360 		err(1, "socket");
361 
362 	memset(&sun, 0, sizeof(sun));
363 	sun.sun_family = AF_UNIX;
364 	if (strlcpy(sun.sun_path, socket_path, sizeof(sun.sun_path)) >=
365 	    sizeof(sun.sun_path))
366 		errx(1, "gotd socket path too long");
367 	if (connect(gotd_sock, (struct sockaddr *)&sun, sizeof(sun)) == -1)
368 		err(1, "connect: %s", socket_path);
369 
370 #ifndef PROFILE
371 	if (pledge("stdio", NULL) == -1)
372 		err(1, "pledge");
373 #endif
374 
375 	return gotd_sock;
376 }
377 
378 int
379 main(int argc, char *argv[])
380 {
381 	const struct gotctl_cmd *cmd;
382 	int gotd_sock = -1, i;
383 	int ch;
384 	int hflag = 0, Vflag = 0;
385 	static const struct option longopts[] = {
386 	    { "version", no_argument, NULL, 'V' },
387 	    { NULL, 0, NULL, 0 }
388 	};
389 	const char *socket_path = GOTD_UNIX_SOCKET;
390 
391 	setlocale(LC_CTYPE, "");
392 
393 #ifndef PROFILE
394 	if (pledge("stdio unix unveil", NULL) == -1)
395 		err(1, "pledge");
396 #endif
397 
398 	while ((ch = getopt_long(argc, argv, "+hf:V", longopts, NULL)) != -1) {
399 		switch (ch) {
400 		case 'h':
401 			hflag = 1;
402 			break;
403 		case 'f':
404 			socket_path = optarg;
405 			break;
406 		case 'V':
407 			Vflag = 1;
408 			break;
409 		default:
410 			usage(hflag, 1);
411 			/* NOTREACHED */
412 		}
413 	}
414 
415 	argc -= optind;
416 	argv += optind;
417 	optind = 1;
418 	optreset = 1;
419 
420 	if (Vflag) {
421 		got_version_print_str();
422 		return 0;
423 	}
424 
425 	if (argc <= 0)
426 		usage(hflag, hflag ? 0 : 1);
427 
428 	for (i = 0; i < nitems(gotctl_commands); i++) {
429 		const struct got_error *error;
430 
431 		cmd = &gotctl_commands[i];
432 
433 		if (strncmp(cmd->cmd_name, argv[0], strlen(argv[0])) != 0)
434 			continue;
435 
436 		if (hflag)
437 			cmd->cmd_usage();
438 
439 		gotd_sock = connect_gotd(socket_path);
440 		if (gotd_sock == -1)
441 			return 1;
442 		error = cmd->cmd_main(argc, argv, gotd_sock);
443 		close(gotd_sock);
444 		if (error) {
445 			fprintf(stderr, "%s: %s\n", getprogname(), error->msg);
446 			return 1;
447 		}
448 
449 		return 0;
450 	}
451 
452 	fprintf(stderr, "%s: unknown command '%s'\n", getprogname(), argv[0]);
453 	list_commands(stderr);
454 	return 1;
455 }