1 /*
2  * Copyright (c) 2019 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/types.h>
18 #include <sys/queue.h>
19 #include <sys/uio.h>
20 #include <sys/time.h>
21 
22 #include <stdint.h>
23 #include <imsg.h>
24 #include <limits.h>
25 #include <signal.h>
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <sha1.h>
30 #include <sha2.h>
31 #include <unistd.h>
32 #include <zlib.h>
33 
34 #include "got_error.h"
35 #include "got_object.h"
36 #include "got_repository.h"
37 
38 #include "got_lib_delta.h"
39 #include "got_lib_object.h"
40 #include "got_lib_privsep.h"
41 #include "got_lib_gitconfig.h"
42 
43 static volatile sig_atomic_t sigint_received;
44 
45 static void
46 catch_sigint(int signo)
47 {
48 	sigint_received = 1;
49 }
50 
51 static const struct got_error *
52 send_gitconfig_int(struct imsgbuf *ibuf, int value)
53 {
54 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_INT_VAL, 0, 0, -1,
55 	    &value, sizeof(value)) == -1)
56 		return got_error_from_errno("imsg_compose GITCONFIG_INT_VAL");
57 
58 	return got_privsep_flush_imsg(ibuf);
59 }
60 
61 static const struct got_error *
62 gitconfig_num_request(struct imsgbuf *ibuf, struct got_gitconfig *gitconfig,
63     const char *section, const char *tag, int def)
64 {
65 	int value;
66 
67 	if (gitconfig == NULL)
68 		return got_error(GOT_ERR_PRIVSEP_MSG);
69 
70 	value = got_gitconfig_get_num(gitconfig, section, tag, def);
71 	return send_gitconfig_int(ibuf, value);
72 }
73 
74 static const struct got_error *
75 send_gitconfig_str(struct imsgbuf *ibuf, const char *value)
76 {
77 	size_t len = value ? strlen(value) : 0;
78 
79 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_STR_VAL, 0, 0, -1,
80 	    value, len) == -1)
81 		return got_error_from_errno("imsg_compose GITCONFIG_STR_VAL");
82 
83 	return got_privsep_flush_imsg(ibuf);
84 }
85 
86 static const struct got_error *
87 send_gitconfig_pair(struct imsgbuf *ibuf, const char *key, const char *val)
88 {
89 	struct ibuf *wbuf;
90 	size_t klen = key ? strlen(key) : 0;
91 	size_t vlen = val ? strlen(val) : 0;
92 	size_t tot = sizeof(klen) + sizeof(vlen) + klen + vlen;
93 
94 	if (tot > MAX_IMSGSIZE - IMSG_HEADER_SIZE)
95 		return got_error(GOT_ERR_NO_SPACE);
96 
97 	wbuf = imsg_create(ibuf, GOT_IMSG_GITCONFIG_PAIR, 0, 0, tot);
98 	if (wbuf == NULL)
99 		return got_error_from_errno("imsg_create GITCONFIG_PAIR");
100 
101 	/* Keep in sync with got_imsg_gitconfig_pair */
102 	if (imsg_add(wbuf, &klen, sizeof(klen)) == -1)
103 		return got_error_from_errno("imsg_add GITCONFIG_PAIR");
104 	if (imsg_add(wbuf, &vlen, sizeof(vlen)) == -1)
105 		return got_error_from_errno("imsg_add GITCONFIG_PAIR");
106 	if (imsg_add(wbuf, key, klen) == -1)
107 		return got_error_from_errno("imsg_add GITCONFIG_PAIR");
108 	if (imsg_add(wbuf, val, vlen) == -1)
109 		return got_error_from_errno("imsg_add GITCONFIG_PAIR");
110 
111 	wbuf->fd = -1;
112 	imsg_close(ibuf, wbuf);
113 	return got_privsep_flush_imsg(ibuf);
114 }
115 
116 static const struct got_error *
117 gitconfig_str_request(struct imsgbuf *ibuf, struct got_gitconfig *gitconfig,
118     const char *section, const char *tag)
119 {
120 	char *value;
121 
122 	if (gitconfig == NULL)
123 		return got_error(GOT_ERR_PRIVSEP_MSG);
124 
125 	value = got_gitconfig_get_str(gitconfig, section, tag);
126 	return send_gitconfig_str(ibuf, value);
127 }
128 
129 static const struct got_error *
130 send_gitconfig_remotes(struct imsgbuf *ibuf, struct got_remote_repo *remotes,
131     int nremotes)
132 {
133 	const struct got_error *err = NULL;
134 	struct got_imsg_remotes iremotes;
135 	int i;
136 
137 	iremotes.nremotes = nremotes;
138 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_REMOTES, 0, 0, -1,
139 	    &iremotes, sizeof(iremotes)) == -1)
140 		return got_error_from_errno("imsg_compose GITCONFIG_REMOTES");
141 
142 	err = got_privsep_flush_imsg(ibuf);
143 	imsg_clear(ibuf);
144 	if (err)
145 		return err;
146 
147 	for (i = 0; i < nremotes; i++) {
148 		struct got_imsg_remote iremote;
149 		size_t len = sizeof(iremote);
150 		struct ibuf *wbuf;
151 
152 		iremote.mirror_references = remotes[i].mirror_references;
153 		iremote.name_len = strlen(remotes[i].name);
154 		len += iremote.name_len;
155 		iremote.fetch_url_len = strlen(remotes[i].fetch_url);
156 		len += iremote.fetch_url_len;
157 		iremote.send_url_len = strlen(remotes[i].send_url);
158 		len += iremote.send_url_len;
159 
160 		wbuf = imsg_create(ibuf, GOT_IMSG_GITCONFIG_REMOTE, 0, 0, len);
161 		if (wbuf == NULL)
162 			return got_error_from_errno(
163 			    "imsg_create GITCONFIG_REMOTE");
164 
165 		if (imsg_add(wbuf, &iremote, sizeof(iremote)) == -1)
166 			return got_error_from_errno(
167 			    "imsg_add GITCONFIG_REMOTE");
168 
169 		if (imsg_add(wbuf, remotes[i].name, iremote.name_len) == -1)
170 			return got_error_from_errno(
171 			    "imsg_add GITCONFIG_REMOTE");
172 		if (imsg_add(wbuf, remotes[i].fetch_url, iremote.fetch_url_len) == -1)
173 			return got_error_from_errno(
174 			    "imsg_add GITCONFIG_REMOTE");
175 		if (imsg_add(wbuf, remotes[i].send_url, iremote.send_url_len) == -1)
176 			return got_error_from_errno(
177 			    "imsg_add GITCONFIG_REMOTE");
178 
179 		wbuf->fd = -1;
180 		imsg_close(ibuf, wbuf);
181 		err = got_privsep_flush_imsg(ibuf);
182 		if (err)
183 			return err;
184 	}
185 
186 	return NULL;
187 }
188 
189 static int
190 get_boolean_val(char *val)
191 {
192     return (strcasecmp(val, "true") == 0 ||
193 	strcasecmp(val, "on") == 0 ||
194 	strcasecmp(val, "yes") == 0 ||
195 	strcmp(val, "1") == 0);
196 }
197 
198 static const struct got_error *
199 gitconfig_remotes_request(struct imsgbuf *ibuf, struct got_gitconfig *gitconfig)
200 {
201 	const struct got_error *err = NULL;
202 	struct got_gitconfig_list *sections;
203 	struct got_gitconfig_list_node *node;
204 	struct got_remote_repo *remotes = NULL;
205 	int nremotes = 0, i;
206 
207 	if (gitconfig == NULL)
208 		return got_error(GOT_ERR_PRIVSEP_MSG);
209 
210 	err = got_gitconfig_get_section_list(&sections, gitconfig);
211 	if (err)
212 		return err;
213 
214 	TAILQ_FOREACH(node, &sections->fields, link) {
215 		if (strncasecmp("remote \"", node->field, 8) != 0)
216 			continue;
217 		nremotes++;
218 	}
219 
220 	if (nremotes == 0) {
221 		err = send_gitconfig_remotes(ibuf, NULL, 0);
222 		goto done;
223 	}
224 
225 	remotes = recallocarray(NULL, 0, nremotes, sizeof(*remotes));
226 	if (remotes == NULL) {
227 		err = got_error_from_errno("recallocarray");
228 		goto done;
229 	}
230 
231 	i = 0;
232 	TAILQ_FOREACH(node, &sections->fields, link) {
233 		char *name, *end, *mirror;
234 
235 		if (strncasecmp("remote \"", node->field, 8) != 0)
236 			continue;
237 
238 		name = strdup(node->field + 8);
239 		if (name == NULL) {
240 			err = got_error_from_errno("strdup");
241 			goto done;
242 		}
243 		end = strrchr(name, '"');
244 		if (end)
245 			*end = '\0';
246 		remotes[i].name = name;
247 
248 		remotes[i].fetch_url = got_gitconfig_get_str(gitconfig,
249 		    node->field, "url");
250 		if (remotes[i].fetch_url == NULL) {
251 			err = got_error(GOT_ERR_GITCONFIG_SYNTAX);
252 			goto done;
253 		}
254 
255 		remotes[i].send_url = got_gitconfig_get_str(gitconfig,
256 		    node->field, "pushurl");
257 		if (remotes[i].send_url == NULL)
258 			remotes[i].send_url = got_gitconfig_get_str(gitconfig,
259 			    node->field, "url");
260 		if (remotes[i].send_url == NULL) {
261 			err = got_error(GOT_ERR_GITCONFIG_SYNTAX);
262 			goto done;
263 		}
264 
265 		remotes[i].mirror_references = 0;
266 		mirror = got_gitconfig_get_str(gitconfig, node->field,
267 		    "mirror");
268 		if (mirror != NULL && get_boolean_val(mirror))
269 			remotes[i].mirror_references = 1;
270 
271 		i++;
272 	}
273 
274 	err = send_gitconfig_remotes(ibuf, remotes, nremotes);
275 done:
276 	for (i = 0; i < nremotes; i++)
277 		free(remotes[i].name);
278 	free(remotes);
279 	got_gitconfig_free_list(sections);
280 	return err;
281 }
282 
283 static const struct got_error *
284 gitconfig_owner_request(struct imsgbuf *ibuf, struct got_gitconfig *gitconfig)
285 {
286 	char *value;
287 
288 	if (gitconfig == NULL)
289 		return got_error(GOT_ERR_PRIVSEP_MSG);
290 
291 	value = got_gitconfig_get_str(gitconfig, "gotweb", "owner");
292 	if (value)
293 		return send_gitconfig_str(ibuf, value);
294 	value = got_gitconfig_get_str(gitconfig, "gitweb", "owner");
295 	return send_gitconfig_str(ibuf, value);
296 }
297 
298 static const struct got_error *
299 gitconfig_extensions_request(struct imsgbuf *ibuf,
300     struct got_gitconfig *gitconfig)
301 {
302 	const struct got_error *err = NULL;
303 	struct got_gitconfig_list *tags;
304 	struct got_gitconfig_list_node *node;
305 	int nextensions = 0;
306 	char *val;
307 
308 	if (gitconfig == NULL)
309 		return got_error(GOT_ERR_PRIVSEP_MSG);
310 
311 	tags = got_gitconfig_get_tag_list(gitconfig, "extensions");
312 	if (tags == NULL)
313 		return send_gitconfig_int(ibuf, 0);
314 
315 	TAILQ_FOREACH(node, &tags->fields, link)
316 		nextensions++;
317 
318 	err = send_gitconfig_int(ibuf, nextensions);
319 	if (err)
320 		goto done;
321 
322 	TAILQ_FOREACH(node, &tags->fields, link) {
323 		val = got_gitconfig_get_str(gitconfig, "extensions",
324 		    node->field);
325 		err = send_gitconfig_pair(ibuf, node->field, val);
326 		if (err)
327 			goto done;
328 	}
329 done:
330 	got_gitconfig_free_list(tags);
331 	return err;
332 }
333 
334 int
335 main(int argc, char *argv[])
336 {
337 	const struct got_error *err = NULL;
338 	struct imsgbuf ibuf;
339 	size_t datalen;
340 	struct got_gitconfig *gitconfig = NULL;
341 #if 0
342 	static int attached;
343 
344 	while (!attached)
345 		sleep(1);
346 #endif
347 	signal(SIGINT, catch_sigint);
348 
349 	imsg_init(&ibuf, GOT_IMSG_FD_CHILD);
350 
351 #ifndef PROFILE
352 	/* revoke access to most system calls */
353 	if (pledge("stdio recvfd", NULL) == -1) {
354 		err = got_error_from_errno("pledge");
355 		got_privsep_send_error(&ibuf, err);
356 		return 1;
357 	}
358 #endif
359 
360 	for (;;) {
361 		struct imsg imsg;
362 
363 		memset(&imsg, 0, sizeof(imsg));
364 		imsg.fd = -1;
365 
366 		if (sigint_received) {
367 			err = got_error(GOT_ERR_CANCELLED);
368 			break;
369 		}
370 
371 		err = got_privsep_recv_imsg(&imsg, &ibuf, 0);
372 		if (err) {
373 			if (err->code == GOT_ERR_PRIVSEP_PIPE)
374 				err = NULL;
375 			break;
376 		}
377 
378 		if (imsg.hdr.type == GOT_IMSG_STOP)
379 			break;
380 
381 		switch (imsg.hdr.type) {
382 		case GOT_IMSG_GITCONFIG_PARSE_REQUEST:
383 			datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
384 			if (datalen != 0) {
385 				err = got_error(GOT_ERR_PRIVSEP_LEN);
386 				break;
387 			}
388 			if (imsg.fd == -1){
389 				err = got_error(GOT_ERR_PRIVSEP_NO_FD);
390 				break;
391 			}
392 
393 			if (gitconfig)
394 				got_gitconfig_close(gitconfig);
395 			err = got_gitconfig_open(&gitconfig, imsg.fd);
396 			break;
397 		case GOT_IMSG_GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST:
398 			err = gitconfig_num_request(&ibuf, gitconfig, "core",
399 			    "repositoryformatversion", 0);
400 			break;
401 		case GOT_IMSG_GITCONFIG_REPOSITORY_EXTENSIONS_REQUEST:
402 			err = gitconfig_extensions_request(&ibuf, gitconfig);
403 			break;
404 		case GOT_IMSG_GITCONFIG_AUTHOR_NAME_REQUEST:
405 			err = gitconfig_str_request(&ibuf, gitconfig, "user",
406 			    "name");
407 			break;
408 		case GOT_IMSG_GITCONFIG_AUTHOR_EMAIL_REQUEST:
409 			err = gitconfig_str_request(&ibuf, gitconfig, "user",
410 			    "email");
411 			break;
412 		case GOT_IMSG_GITCONFIG_REMOTES_REQUEST:
413 			err = gitconfig_remotes_request(&ibuf, gitconfig);
414 			break;
415 		case GOT_IMSG_GITCONFIG_OWNER_REQUEST:
416 			err = gitconfig_owner_request(&ibuf, gitconfig);
417 			break;
418 		default:
419 			err = got_error(GOT_ERR_PRIVSEP_MSG);
420 			break;
421 		}
422 
423 		if (imsg.fd != -1) {
424 			if (close(imsg.fd) == -1 && err == NULL)
425 				err = got_error_from_errno("close");
426 		}
427 
428 		imsg_free(&imsg);
429 		if (err)
430 			break;
431 	}
432 
433 	imsg_clear(&ibuf);
434 	if (err) {
435 		if (!sigint_received && err->code != GOT_ERR_PRIVSEP_PIPE) {
436 			fprintf(stderr, "%s: %s\n", getprogname(), err->msg);
437 			got_privsep_send_error(&ibuf, err);
438 		}
439 	}
440 	if (close(GOT_IMSG_FD_CHILD) == -1 && err == NULL)
441 		err = got_error_from_errno("close");
442 	return err ? 1 : 0;
443 }