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.is_writing)
151 		printf("writing to %s\n", info.repo_name);
152 	else
153 		printf("reading from %s\n", info.repo_name);
154 
155 	return NULL;
156 }
157 
158 static const struct got_error *
159 show_capability(struct imsg *imsg)
160 {
161 	struct gotd_imsg_capability icapa;
162 	size_t datalen;
163 	char *key, *value = NULL;
164 
165 	memset(&icapa, 0, sizeof(icapa));
166 
167 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
168 	if (datalen < sizeof(icapa))
169 		return got_error(GOT_ERR_PRIVSEP_LEN);
170 	memcpy(&icapa, imsg->data, sizeof(icapa));
171 
172 	if (datalen != sizeof(icapa) + icapa.key_len + icapa.value_len)
173 		return got_error(GOT_ERR_PRIVSEP_LEN);
174 
175 	key = malloc(icapa.key_len + 1);
176 	if (key == NULL)
177 		return got_error_from_errno("malloc");
178 	if (icapa.value_len > 0) {
179 		value = malloc(icapa.value_len + 1);
180 		if (value == NULL) {
181 			free(key);
182 			return got_error_from_errno("malloc");
183 		}
184 	}
185 
186 	memcpy(key, imsg->data + sizeof(icapa), icapa.key_len);
187 	key[icapa.key_len] = '\0';
188 	if (value) {
189 		memcpy(value, imsg->data + sizeof(icapa) + icapa.key_len,
190 		    icapa.value_len);
191 		value[icapa.value_len] = '\0';
192 	}
193 
194 	if (strcmp(key, GOT_CAPA_AGENT) == 0)
195 		printf("  client user agent: %s\n", value);
196 	else if (value)
197 		printf("  client supports %s=%s\n", key, value);
198 	else
199 		printf("  client supports %s\n", key);
200 
201 	free(key);
202 	free(value);
203 	return NULL;
204 }
205 
206 static const struct got_error *
207 cmd_info(int argc, char *argv[], int gotd_sock)
208 {
209 	const struct got_error *err;
210 	struct imsgbuf ibuf;
211 	struct imsg imsg;
212 
213 	imsg_init(&ibuf, gotd_sock);
214 
215 	if (imsg_compose(&ibuf, GOTD_IMSG_INFO, 0, 0, -1, NULL, 0) == -1)
216 		return got_error_from_errno("imsg_compose INFO");
217 
218 	err = gotd_imsg_flush(&ibuf);
219 	while (err == NULL) {
220 		err = gotd_imsg_poll_recv(&imsg, &ibuf, 0);
221 		if (err) {
222 			if (err->code == GOT_ERR_EOF)
223 				err = NULL;
224 			break;
225 		}
226 		
227 		switch (imsg.hdr.type) {
228 		case GOTD_IMSG_ERROR:
229 			err = gotd_imsg_recv_error(NULL, &imsg);
230 			break;
231 		case GOTD_IMSG_INFO:
232 			err = show_info(&imsg);
233 			break;
234 		case GOTD_IMSG_INFO_REPO:
235 			err = show_repo_info(&imsg);
236 			break;
237 		case GOTD_IMSG_INFO_CLIENT:
238 			err = show_client_info(&imsg);
239 			break;
240 		case GOTD_IMSG_CAPABILITY:
241 			err = show_capability(&imsg);
242 			break;
243 		default:
244 			err = got_error(GOT_ERR_PRIVSEP_MSG);
245 			break;
246 		}
247 
248 		imsg_free(&imsg);
249 	}
250 
251 	imsg_clear(&ibuf);
252 	return err;
253 }
254 
255 __dead static void
256 usage_stop(void)
257 {
258 	fprintf(stderr, "usage: %s stop\n", getprogname());
259 	exit(1);
260 }
261 
262 static const struct got_error *
263 cmd_stop(int argc, char *argv[], int gotd_sock)
264 {
265 	const struct got_error *err;
266 	struct imsgbuf ibuf;
267 	struct imsg imsg;
268 
269 	imsg_init(&ibuf, gotd_sock);
270 
271 	if (imsg_compose(&ibuf, GOTD_IMSG_STOP, 0, 0, -1, NULL, 0) == -1)
272 		return got_error_from_errno("imsg_compose STOP");
273 
274 	err = gotd_imsg_flush(&ibuf);
275 	while (err == NULL) {
276 		err = gotd_imsg_poll_recv(&imsg, &ibuf, 0);
277 		if (err) {
278 			if (err->code == GOT_ERR_EOF)
279 				err = NULL;
280 			break;
281 		}
282 		
283 		switch (imsg.hdr.type) {
284 		case GOTD_IMSG_ERROR:
285 			err = gotd_imsg_recv_error(NULL, &imsg);
286 			break;
287 		default:
288 			err = got_error(GOT_ERR_PRIVSEP_MSG);
289 			break;
290 		}
291 
292 		imsg_free(&imsg);
293 	}
294 
295 	imsg_clear(&ibuf);
296 	return err;
297 }
298 
299 static void
300 list_commands(FILE *fp)
301 {
302 	size_t i;
303 
304 	fprintf(fp, "commands:");
305 	for (i = 0; i < nitems(gotctl_commands); i++) {
306 		const struct gotctl_cmd *cmd = &gotctl_commands[i];
307 		fprintf(fp, " %s", cmd->cmd_name);
308 	}
309 	fputc('\n', fp);
310 }
311 
312 __dead static void
313 usage(int hflag, int status)
314 {
315 	FILE *fp = (status == 0) ? stdout : stderr;
316 
317 	fprintf(fp, "usage: %s [-hV] [-f path] command [arg ...]\n",
318 	    getprogname());
319 	if (hflag)
320 		list_commands(fp);
321 	exit(status);
322 }
323 
324 static const struct got_error *
325 apply_unveil(const char *unix_socket_path)
326 {
327 #ifdef PROFILE
328 	if (unveil("gmon.out", "rwc") != 0)
329 		return got_error_from_errno2("unveil", "gmon.out");
330 #endif
331 	if (unveil(unix_socket_path, "w") != 0)
332 		return got_error_from_errno2("unveil", unix_socket_path);
333 
334 	if (unveil(NULL, NULL) != 0)
335 		return got_error_from_errno("unveil");
336 
337 	return NULL;
338 }
339 
340 static int
341 connect_gotd(const char *socket_path)
342 {
343 	const struct got_error *error = NULL;
344 	int gotd_sock = -1;
345 	struct sockaddr_un sun;
346 
347 	error = apply_unveil(socket_path);
348 	if (error)
349 		errx(1, "%s", error->msg);
350 
351 #ifndef PROFILE
352 	if (pledge("stdio unix", NULL) == -1)
353 		err(1, "pledge");
354 #endif
355 	if ((gotd_sock = socket(AF_UNIX, SOCK_STREAM, 0)) == -1)
356 		err(1, "socket");
357 
358 	memset(&sun, 0, sizeof(sun));
359 	sun.sun_family = AF_UNIX;
360 	if (strlcpy(sun.sun_path, socket_path, sizeof(sun.sun_path)) >=
361 	    sizeof(sun.sun_path))
362 		errx(1, "gotd socket path too long");
363 	if (connect(gotd_sock, (struct sockaddr *)&sun, sizeof(sun)) == -1)
364 		err(1, "connect: %s", socket_path);
365 
366 #ifndef PROFILE
367 	if (pledge("stdio", NULL) == -1)
368 		err(1, "pledge");
369 #endif
370 
371 	return gotd_sock;
372 }
373 
374 int
375 main(int argc, char *argv[])
376 {
377 	const struct gotctl_cmd *cmd;
378 	int gotd_sock = -1, i;
379 	int ch;
380 	int hflag = 0, Vflag = 0;
381 	static const struct option longopts[] = {
382 	    { "version", no_argument, NULL, 'V' },
383 	    { NULL, 0, NULL, 0 }
384 	};
385 	const char *socket_path = GOTD_UNIX_SOCKET;
386 
387 	setlocale(LC_CTYPE, "");
388 
389 #ifndef PROFILE
390 	if (pledge("stdio unix unveil", NULL) == -1)
391 		err(1, "pledge");
392 #endif
393 
394 	while ((ch = getopt_long(argc, argv, "+hf:V", longopts, NULL)) != -1) {
395 		switch (ch) {
396 		case 'h':
397 			hflag = 1;
398 			break;
399 		case 'f':
400 			socket_path = optarg;
401 			break;
402 		case 'V':
403 			Vflag = 1;
404 			break;
405 		default:
406 			usage(hflag, 1);
407 			/* NOTREACHED */
408 		}
409 	}
410 
411 	argc -= optind;
412 	argv += optind;
413 	optind = 1;
414 	optreset = 1;
415 
416 	if (Vflag) {
417 		got_version_print_str();
418 		return 0;
419 	}
420 
421 	if (argc <= 0)
422 		usage(hflag, hflag ? 0 : 1);
423 
424 	for (i = 0; i < nitems(gotctl_commands); i++) {
425 		const struct got_error *error;
426 
427 		cmd = &gotctl_commands[i];
428 
429 		if (strncmp(cmd->cmd_name, argv[0], strlen(argv[0])) != 0)
430 			continue;
431 
432 		if (hflag)
433 			cmd->cmd_usage();
434 
435 		gotd_sock = connect_gotd(socket_path);
436 		if (gotd_sock == -1)
437 			return 1;
438 		error = cmd->cmd_main(argc, argv, gotd_sock);
439 		close(gotd_sock);
440 		if (error) {
441 			fprintf(stderr, "%s: %s\n", getprogname(), error->msg);
442 			return 1;
443 		}
444 
445 		return 0;
446 	}
447 
448 	fprintf(stderr, "%s: unknown command '%s'\n", getprogname(), argv[0]);
449 	list_commands(stderr);
450 	return 1;
451 }