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