Make some strings const
[git/git.git] / connect.c
1 #include "git-compat-util.h"
2 #include "cache.h"
3 #include "pkt-line.h"
4 #include "quote.h"
5 #include "refs.h"
6 #include <sys/wait.h>
7 #include <sys/socket.h>
8 #include <netinet/in.h>
9 #include <arpa/inet.h>
10 #include <netdb.h>
11 #include <signal.h>
12
13 static char *server_capabilities = NULL;
14
15 /*
16 * Read all the refs from the other end
17 */
18 struct ref **get_remote_heads(int in, struct ref **list,
19 int nr_match, char **match, int ignore_funny)
20 {
21 *list = NULL;
22 for (;;) {
23 struct ref *ref;
24 unsigned char old_sha1[20];
25 static char buffer[1000];
26 char *name;
27 int len, name_len;
28
29 len = packet_read_line(in, buffer, sizeof(buffer));
30 if (!len)
31 break;
32 if (buffer[len-1] == '\n')
33 buffer[--len] = 0;
34
35 if (len < 42 || get_sha1_hex(buffer, old_sha1) || buffer[40] != ' ')
36 die("protocol error: expected sha/ref, got '%s'", buffer);
37 name = buffer + 41;
38
39 name_len = strlen(name);
40 if (len != name_len + 41) {
41 if (server_capabilities)
42 free(server_capabilities);
43 server_capabilities = strdup(name + name_len + 1);
44 }
45
46 if (ignore_funny && 45 < len && !memcmp(name, "refs/", 5) &&
47 check_ref_format(name + 5))
48 continue;
49
50 if (nr_match && !path_match(name, nr_match, match))
51 continue;
52 ref = xcalloc(1, sizeof(*ref) + len - 40);
53 memcpy(ref->old_sha1, old_sha1, 20);
54 memcpy(ref->name, buffer + 41, len - 40);
55 *list = ref;
56 list = &ref->next;
57 }
58 return list;
59 }
60
61 int server_supports(const char *feature)
62 {
63 return server_capabilities &&
64 strstr(server_capabilities, feature) != NULL;
65 }
66
67 int get_ack(int fd, unsigned char *result_sha1)
68 {
69 static char line[1000];
70 int len = packet_read_line(fd, line, sizeof(line));
71
72 if (!len)
73 die("git-fetch-pack: expected ACK/NAK, got EOF");
74 if (line[len-1] == '\n')
75 line[--len] = 0;
76 if (!strcmp(line, "NAK"))
77 return 0;
78 if (!strncmp(line, "ACK ", 4)) {
79 if (!get_sha1_hex(line+4, result_sha1)) {
80 if (strstr(line+45, "continue"))
81 return 2;
82 return 1;
83 }
84 }
85 die("git-fetch_pack: expected ACK/NAK, got '%s'", line);
86 }
87
88 int path_match(const char *path, int nr, char **match)
89 {
90 int i;
91 int pathlen = strlen(path);
92
93 for (i = 0; i < nr; i++) {
94 char *s = match[i];
95 int len = strlen(s);
96
97 if (!len || len > pathlen)
98 continue;
99 if (memcmp(path + pathlen - len, s, len))
100 continue;
101 if (pathlen > len && path[pathlen - len - 1] != '/')
102 continue;
103 *s = 0;
104 return (i + 1);
105 }
106 return 0;
107 }
108
109 struct refspec {
110 char *src;
111 char *dst;
112 char force;
113 };
114
115 /*
116 * A:B means fast forward remote B with local A.
117 * +A:B means overwrite remote B with local A.
118 * +A is a shorthand for +A:A.
119 * A is a shorthand for A:A.
120 */
121 static struct refspec *parse_ref_spec(int nr_refspec, char **refspec)
122 {
123 int i;
124 struct refspec *rs = xcalloc(sizeof(*rs), (nr_refspec + 1));
125 for (i = 0; i < nr_refspec; i++) {
126 char *sp, *dp, *ep;
127 sp = refspec[i];
128 if (*sp == '+') {
129 rs[i].force = 1;
130 sp++;
131 }
132 ep = strchr(sp, ':');
133 if (ep) {
134 dp = ep + 1;
135 *ep = 0;
136 }
137 else
138 dp = sp;
139 rs[i].src = sp;
140 rs[i].dst = dp;
141 }
142 rs[nr_refspec].src = rs[nr_refspec].dst = NULL;
143 return rs;
144 }
145
146 static int count_refspec_match(const char *pattern,
147 struct ref *refs,
148 struct ref **matched_ref)
149 {
150 int match;
151 int patlen = strlen(pattern);
152
153 for (match = 0; refs; refs = refs->next) {
154 char *name = refs->name;
155 int namelen = strlen(name);
156 if (namelen < patlen ||
157 memcmp(name + namelen - patlen, pattern, patlen))
158 continue;
159 if (namelen != patlen && name[namelen - patlen - 1] != '/')
160 continue;
161 match++;
162 *matched_ref = refs;
163 }
164 return match;
165 }
166
167 static void link_dst_tail(struct ref *ref, struct ref ***tail)
168 {
169 **tail = ref;
170 *tail = &ref->next;
171 **tail = NULL;
172 }
173
174 static struct ref *try_explicit_object_name(const char *name)
175 {
176 unsigned char sha1[20];
177 struct ref *ref;
178 int len;
179 if (get_sha1(name, sha1))
180 return NULL;
181 len = strlen(name) + 1;
182 ref = xcalloc(1, sizeof(*ref) + len);
183 memcpy(ref->name, name, len);
184 memcpy(ref->new_sha1, sha1, 20);
185 return ref;
186 }
187
188 static int match_explicit_refs(struct ref *src, struct ref *dst,
189 struct ref ***dst_tail, struct refspec *rs)
190 {
191 int i, errs;
192 for (i = errs = 0; rs[i].src; i++) {
193 struct ref *matched_src, *matched_dst;
194
195 matched_src = matched_dst = NULL;
196 switch (count_refspec_match(rs[i].src, src, &matched_src)) {
197 case 1:
198 break;
199 case 0:
200 /* The source could be in the get_sha1() format
201 * not a reference name.
202 */
203 matched_src = try_explicit_object_name(rs[i].src);
204 if (matched_src)
205 break;
206 errs = 1;
207 error("src refspec %s does not match any.",
208 rs[i].src);
209 break;
210 default:
211 errs = 1;
212 error("src refspec %s matches more than one.",
213 rs[i].src);
214 break;
215 }
216 switch (count_refspec_match(rs[i].dst, dst, &matched_dst)) {
217 case 1:
218 break;
219 case 0:
220 if (!memcmp(rs[i].dst, "refs/", 5)) {
221 int len = strlen(rs[i].dst) + 1;
222 matched_dst = xcalloc(1, sizeof(*dst) + len);
223 memcpy(matched_dst->name, rs[i].dst, len);
224 link_dst_tail(matched_dst, dst_tail);
225 }
226 else if (!strcmp(rs[i].src, rs[i].dst) &&
227 matched_src) {
228 /* pushing "master:master" when
229 * remote does not have master yet.
230 */
231 int len = strlen(matched_src->name) + 1;
232 matched_dst = xcalloc(1, sizeof(*dst) + len);
233 memcpy(matched_dst->name, matched_src->name,
234 len);
235 link_dst_tail(matched_dst, dst_tail);
236 }
237 else {
238 errs = 1;
239 error("dst refspec %s does not match any "
240 "existing ref on the remote and does "
241 "not start with refs/.", rs[i].dst);
242 }
243 break;
244 default:
245 errs = 1;
246 error("dst refspec %s matches more than one.",
247 rs[i].dst);
248 break;
249 }
250 if (errs)
251 continue;
252 if (matched_dst->peer_ref) {
253 errs = 1;
254 error("dst ref %s receives from more than one src.",
255 matched_dst->name);
256 }
257 else {
258 matched_dst->peer_ref = matched_src;
259 matched_dst->force = rs[i].force;
260 }
261 }
262 return -errs;
263 }
264
265 static struct ref *find_ref_by_name(struct ref *list, const char *name)
266 {
267 for ( ; list; list = list->next)
268 if (!strcmp(list->name, name))
269 return list;
270 return NULL;
271 }
272
273 int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
274 int nr_refspec, char **refspec, int all)
275 {
276 struct refspec *rs = parse_ref_spec(nr_refspec, refspec);
277
278 if (nr_refspec)
279 return match_explicit_refs(src, dst, dst_tail, rs);
280
281 /* pick the remainder */
282 for ( ; src; src = src->next) {
283 struct ref *dst_peer;
284 if (src->peer_ref)
285 continue;
286 dst_peer = find_ref_by_name(dst, src->name);
287 if ((dst_peer && dst_peer->peer_ref) || (!dst_peer && !all))
288 continue;
289 if (!dst_peer) {
290 /* Create a new one and link it */
291 int len = strlen(src->name) + 1;
292 dst_peer = xcalloc(1, sizeof(*dst_peer) + len);
293 memcpy(dst_peer->name, src->name, len);
294 memcpy(dst_peer->new_sha1, src->new_sha1, 20);
295 link_dst_tail(dst_peer, dst_tail);
296 }
297 dst_peer->peer_ref = src;
298 }
299 return 0;
300 }
301
302 enum protocol {
303 PROTO_LOCAL = 1,
304 PROTO_SSH,
305 PROTO_GIT,
306 };
307
308 static enum protocol get_protocol(const char *name)
309 {
310 if (!strcmp(name, "ssh"))
311 return PROTO_SSH;
312 if (!strcmp(name, "git"))
313 return PROTO_GIT;
314 if (!strcmp(name, "git+ssh"))
315 return PROTO_SSH;
316 if (!strcmp(name, "ssh+git"))
317 return PROTO_SSH;
318 die("I don't handle protocol '%s'", name);
319 }
320
321 #define STR_(s) # s
322 #define STR(s) STR_(s)
323
324 #ifndef NO_IPV6
325
326 /*
327 * Returns a connected socket() fd, or else die()s.
328 */
329 static int git_tcp_connect_sock(char *host)
330 {
331 int sockfd = -1;
332 char *colon, *end;
333 const char *port = STR(DEFAULT_GIT_PORT);
334 struct addrinfo hints, *ai0, *ai;
335 int gai;
336
337 if (host[0] == '[') {
338 end = strchr(host + 1, ']');
339 if (end) {
340 *end = 0;
341 end++;
342 host++;
343 } else
344 end = host;
345 } else
346 end = host;
347 colon = strchr(end, ':');
348
349 if (colon) {
350 *colon = 0;
351 port = colon + 1;
352 }
353
354 memset(&hints, 0, sizeof(hints));
355 hints.ai_socktype = SOCK_STREAM;
356 hints.ai_protocol = IPPROTO_TCP;
357
358 gai = getaddrinfo(host, port, &hints, &ai);
359 if (gai)
360 die("Unable to look up %s (%s)", host, gai_strerror(gai));
361
362 for (ai0 = ai; ai; ai = ai->ai_next) {
363 sockfd = socket(ai->ai_family,
364 ai->ai_socktype, ai->ai_protocol);
365 if (sockfd < 0)
366 continue;
367 if (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
368 close(sockfd);
369 sockfd = -1;
370 continue;
371 }
372 break;
373 }
374
375 freeaddrinfo(ai0);
376
377 if (sockfd < 0)
378 die("unable to connect a socket (%s)", strerror(errno));
379
380 return sockfd;
381 }
382
383 #else /* NO_IPV6 */
384
385 /*
386 * Returns a connected socket() fd, or else die()s.
387 */
388 static int git_tcp_connect_sock(char *host)
389 {
390 int sockfd = -1;
391 char *colon, *end;
392 char *port = STR(DEFAULT_GIT_PORT), *ep;
393 struct hostent *he;
394 struct sockaddr_in sa;
395 char **ap;
396 unsigned int nport;
397
398 if (host[0] == '[') {
399 end = strchr(host + 1, ']');
400 if (end) {
401 *end = 0;
402 end++;
403 host++;
404 } else
405 end = host;
406 } else
407 end = host;
408 colon = strchr(end, ':');
409
410 if (colon) {
411 *colon = 0;
412 port = colon + 1;
413 }
414
415 he = gethostbyname(host);
416 if (!he)
417 die("Unable to look up %s (%s)", host, hstrerror(h_errno));
418 nport = strtoul(port, &ep, 10);
419 if ( ep == port || *ep ) {
420 /* Not numeric */
421 struct servent *se = getservbyname(port,"tcp");
422 if ( !se )
423 die("Unknown port %s\n", port);
424 nport = se->s_port;
425 }
426
427 for (ap = he->h_addr_list; *ap; ap++) {
428 sockfd = socket(he->h_addrtype, SOCK_STREAM, 0);
429 if (sockfd < 0)
430 continue;
431
432 memset(&sa, 0, sizeof sa);
433 sa.sin_family = he->h_addrtype;
434 sa.sin_port = htons(nport);
435 memcpy(&sa.sin_addr, *ap, he->h_length);
436
437 if (connect(sockfd, (struct sockaddr *)&sa, sizeof sa) < 0) {
438 close(sockfd);
439 sockfd = -1;
440 continue;
441 }
442 break;
443 }
444
445 if (sockfd < 0)
446 die("unable to connect a socket (%s)", strerror(errno));
447
448 return sockfd;
449 }
450
451 #endif /* NO_IPV6 */
452
453
454 static void git_tcp_connect(int fd[2],
455 const char *prog, char *host, char *path)
456 {
457 int sockfd = git_tcp_connect_sock(host);
458
459 fd[0] = sockfd;
460 fd[1] = sockfd;
461 }
462
463
464 static char *git_proxy_command = NULL;
465 static const char *rhost_name = NULL;
466 static int rhost_len;
467
468 static int git_proxy_command_options(const char *var, const char *value)
469 {
470 if (!strcmp(var, "core.gitproxy")) {
471 const char *for_pos;
472 int matchlen = -1;
473 int hostlen;
474
475 if (git_proxy_command)
476 return 0;
477 /* [core]
478 * ;# matches www.kernel.org as well
479 * gitproxy = netcatter-1 for kernel.org
480 * gitproxy = netcatter-2 for sample.xz
481 * gitproxy = netcatter-default
482 */
483 for_pos = strstr(value, " for ");
484 if (!for_pos)
485 /* matches everybody */
486 matchlen = strlen(value);
487 else {
488 hostlen = strlen(for_pos + 5);
489 if (rhost_len < hostlen)
490 matchlen = -1;
491 else if (!strncmp(for_pos + 5,
492 rhost_name + rhost_len - hostlen,
493 hostlen) &&
494 ((rhost_len == hostlen) ||
495 rhost_name[rhost_len - hostlen -1] == '.'))
496 matchlen = for_pos - value;
497 else
498 matchlen = -1;
499 }
500 if (0 <= matchlen) {
501 /* core.gitproxy = none for kernel.org */
502 if (matchlen == 4 &&
503 !memcmp(value, "none", 4))
504 matchlen = 0;
505 git_proxy_command = xmalloc(matchlen + 1);
506 memcpy(git_proxy_command, value, matchlen);
507 git_proxy_command[matchlen] = 0;
508 }
509 return 0;
510 }
511
512 return git_default_config(var, value);
513 }
514
515 static int git_use_proxy(const char *host)
516 {
517 rhost_name = host;
518 rhost_len = strlen(host);
519 git_proxy_command = getenv("GIT_PROXY_COMMAND");
520 git_config(git_proxy_command_options);
521 rhost_name = NULL;
522 return (git_proxy_command && *git_proxy_command);
523 }
524
525 static void git_proxy_connect(int fd[2],
526 const char *prog, char *host, char *path)
527 {
528 const char *port = STR(DEFAULT_GIT_PORT);
529 char *colon, *end;
530 int pipefd[2][2];
531 pid_t pid;
532
533 if (host[0] == '[') {
534 end = strchr(host + 1, ']');
535 if (end) {
536 *end = 0;
537 end++;
538 host++;
539 } else
540 end = host;
541 } else
542 end = host;
543 colon = strchr(end, ':');
544
545 if (colon) {
546 *colon = 0;
547 port = colon + 1;
548 }
549
550 if (pipe(pipefd[0]) < 0 || pipe(pipefd[1]) < 0)
551 die("unable to create pipe pair for communication");
552 pid = fork();
553 if (!pid) {
554 dup2(pipefd[1][0], 0);
555 dup2(pipefd[0][1], 1);
556 close(pipefd[0][0]);
557 close(pipefd[0][1]);
558 close(pipefd[1][0]);
559 close(pipefd[1][1]);
560 execlp(git_proxy_command, git_proxy_command, host, port, NULL);
561 die("exec failed");
562 }
563 if (pid < 0)
564 die("fork failed");
565 fd[0] = pipefd[0][0];
566 fd[1] = pipefd[1][1];
567 close(pipefd[0][1]);
568 close(pipefd[1][0]);
569 }
570
571 /*
572 * Yeah, yeah, fixme. Need to pass in the heads etc.
573 */
574 int git_connect(int fd[2], char *url, const char *prog)
575 {
576 char command[1024];
577 char *host, *path = url;
578 char *end;
579 int c;
580 int pipefd[2][2];
581 pid_t pid;
582 enum protocol protocol = PROTO_LOCAL;
583 int free_path = 0;
584
585 /* Without this we cannot rely on waitpid() to tell
586 * what happened to our children.
587 */
588 signal(SIGCHLD, SIG_DFL);
589
590 host = strstr(url, "://");
591 if(host) {
592 *host = '\0';
593 protocol = get_protocol(url);
594 host += 3;
595 c = '/';
596 } else {
597 host = url;
598 c = ':';
599 }
600
601 if (host[0] == '[') {
602 end = strchr(host + 1, ']');
603 if (end) {
604 *end = 0;
605 end++;
606 host++;
607 } else
608 end = host;
609 } else
610 end = host;
611
612 path = strchr(end, c);
613 if (c == ':') {
614 if (path) {
615 protocol = PROTO_SSH;
616 *path++ = '\0';
617 } else
618 path = host;
619 }
620
621 if (!path || !*path)
622 die("No path specified. See 'man git-pull' for valid url syntax");
623
624 /*
625 * null-terminate hostname and point path to ~ for URL's like this:
626 * ssh://host.xz/~user/repo
627 */
628 if (protocol != PROTO_LOCAL && host != url) {
629 char *ptr = path;
630 if (path[1] == '~')
631 path++;
632 else {
633 path = strdup(ptr);
634 free_path = 1;
635 }
636
637 *ptr = '\0';
638 }
639
640 if (protocol == PROTO_GIT) {
641 /* These underlying connection commands die() if they
642 * cannot connect.
643 */
644 char *target_host = strdup(host);
645 if (git_use_proxy(host))
646 git_proxy_connect(fd, prog, host, path);
647 else
648 git_tcp_connect(fd, prog, host, path);
649 /*
650 * Separate original protocol components prog and path
651 * from extended components with a NUL byte.
652 */
653 packet_write(fd[1],
654 "%s %s%chost=%s%c",
655 prog, path, 0,
656 target_host, 0);
657 free(target_host);
658 if (free_path)
659 free(path);
660 return 0;
661 }
662
663 if (pipe(pipefd[0]) < 0 || pipe(pipefd[1]) < 0)
664 die("unable to create pipe pair for communication");
665 pid = fork();
666 if (pid < 0)
667 die("unable to fork");
668 if (!pid) {
669 snprintf(command, sizeof(command), "%s %s", prog,
670 sq_quote(path));
671 dup2(pipefd[1][0], 0);
672 dup2(pipefd[0][1], 1);
673 close(pipefd[0][0]);
674 close(pipefd[0][1]);
675 close(pipefd[1][0]);
676 close(pipefd[1][1]);
677 if (protocol == PROTO_SSH) {
678 const char *ssh, *ssh_basename;
679 ssh = getenv("GIT_SSH");
680 if (!ssh) ssh = "ssh";
681 ssh_basename = strrchr(ssh, '/');
682 if (!ssh_basename)
683 ssh_basename = ssh;
684 else
685 ssh_basename++;
686 execlp(ssh, ssh_basename, host, command, NULL);
687 }
688 else {
689 unsetenv(ALTERNATE_DB_ENVIRONMENT);
690 unsetenv(DB_ENVIRONMENT);
691 unsetenv(GIT_DIR_ENVIRONMENT);
692 unsetenv(GRAFT_ENVIRONMENT);
693 unsetenv(INDEX_ENVIRONMENT);
694 execlp("sh", "sh", "-c", command, NULL);
695 }
696 die("exec failed");
697 }
698 fd[0] = pipefd[0][0];
699 fd[1] = pipefd[1][1];
700 close(pipefd[0][1]);
701 close(pipefd[1][0]);
702 if (free_path)
703 free(path);
704 return pid;
705 }
706
707 int finish_connect(pid_t pid)
708 {
709 int ret;
710
711 for (;;) {
712 ret = waitpid(pid, NULL, 0);
713 if (!ret)
714 break;
715 if (errno != EINTR)
716 break;
717 }
718 return ret;
719 }