db7342e4d26baa50dd944ebf06fb8b66fea59aaa
[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
12 static char *server_capabilities = NULL;
13
14 /*
15 * Read all the refs from the other end
16 */
17 struct ref **get_remote_heads(int in, struct ref **list,
18 int nr_match, char **match, int ignore_funny)
19 {
20 *list = NULL;
21 for (;;) {
22 struct ref *ref;
23 unsigned char old_sha1[20];
24 static char buffer[1000];
25 char *name;
26 int len, name_len;
27
28 len = packet_read_line(in, buffer, sizeof(buffer));
29 if (!len)
30 break;
31 if (buffer[len-1] == '\n')
32 buffer[--len] = 0;
33
34 if (len < 42 || get_sha1_hex(buffer, old_sha1) || buffer[40] != ' ')
35 die("protocol error: expected sha/ref, got '%s'", buffer);
36 name = buffer + 41;
37
38 name_len = strlen(name);
39 if (len != name_len + 41) {
40 if (server_capabilities)
41 free(server_capabilities);
42 server_capabilities = strdup(name + name_len + 1);
43 }
44
45 if (ignore_funny && 45 < len && !memcmp(name, "refs/", 5) &&
46 check_ref_format(name + 5))
47 continue;
48
49 if (nr_match && !path_match(name, nr_match, match))
50 continue;
51 ref = xcalloc(1, sizeof(*ref) + len - 40);
52 memcpy(ref->old_sha1, old_sha1, 20);
53 memcpy(ref->name, buffer + 41, len - 40);
54 *list = ref;
55 list = &ref->next;
56 }
57 return list;
58 }
59
60 int server_supports(const char *feature)
61 {
62 return server_capabilities &&
63 strstr(server_capabilities, feature) != NULL;
64 }
65
66 int get_ack(int fd, unsigned char *result_sha1)
67 {
68 static char line[1000];
69 int len = packet_read_line(fd, line, sizeof(line));
70
71 if (!len)
72 die("git-fetch-pack: expected ACK/NAK, got EOF");
73 if (line[len-1] == '\n')
74 line[--len] = 0;
75 if (!strcmp(line, "NAK"))
76 return 0;
77 if (!strncmp(line, "ACK ", 4)) {
78 if (!get_sha1_hex(line+4, result_sha1)) {
79 if (strstr(line+45, "continue"))
80 return 2;
81 return 1;
82 }
83 }
84 die("git-fetch_pack: expected ACK/NAK, got '%s'", line);
85 }
86
87 int path_match(const char *path, int nr, char **match)
88 {
89 int i;
90 int pathlen = strlen(path);
91
92 for (i = 0; i < nr; i++) {
93 char *s = match[i];
94 int len = strlen(s);
95
96 if (!len || len > pathlen)
97 continue;
98 if (memcmp(path + pathlen - len, s, len))
99 continue;
100 if (pathlen > len && path[pathlen - len - 1] != '/')
101 continue;
102 *s = 0;
103 return (i + 1);
104 }
105 return 0;
106 }
107
108 struct refspec {
109 char *src;
110 char *dst;
111 char force;
112 };
113
114 /*
115 * A:B means fast forward remote B with local A.
116 * +A:B means overwrite remote B with local A.
117 * +A is a shorthand for +A:A.
118 * A is a shorthand for A:A.
119 */
120 static struct refspec *parse_ref_spec(int nr_refspec, char **refspec)
121 {
122 int i;
123 struct refspec *rs = xcalloc(sizeof(*rs), (nr_refspec + 1));
124 for (i = 0; i < nr_refspec; i++) {
125 char *sp, *dp, *ep;
126 sp = refspec[i];
127 if (*sp == '+') {
128 rs[i].force = 1;
129 sp++;
130 }
131 ep = strchr(sp, ':');
132 if (ep) {
133 dp = ep + 1;
134 *ep = 0;
135 }
136 else
137 dp = sp;
138 rs[i].src = sp;
139 rs[i].dst = dp;
140 }
141 rs[nr_refspec].src = rs[nr_refspec].dst = NULL;
142 return rs;
143 }
144
145 static int count_refspec_match(const char *pattern,
146 struct ref *refs,
147 struct ref **matched_ref)
148 {
149 int match;
150 int patlen = strlen(pattern);
151
152 for (match = 0; refs; refs = refs->next) {
153 char *name = refs->name;
154 int namelen = strlen(name);
155 if (namelen < patlen ||
156 memcmp(name + namelen - patlen, pattern, patlen))
157 continue;
158 if (namelen != patlen && name[namelen - patlen - 1] != '/')
159 continue;
160 match++;
161 *matched_ref = refs;
162 }
163 return match;
164 }
165
166 static void link_dst_tail(struct ref *ref, struct ref ***tail)
167 {
168 **tail = ref;
169 *tail = &ref->next;
170 **tail = NULL;
171 }
172
173 static struct ref *try_explicit_object_name(const char *name)
174 {
175 unsigned char sha1[20];
176 struct ref *ref;
177 int len;
178 if (get_sha1(name, sha1))
179 return NULL;
180 len = strlen(name) + 1;
181 ref = xcalloc(1, sizeof(*ref) + len);
182 memcpy(ref->name, name, len);
183 memcpy(ref->new_sha1, sha1, 20);
184 return ref;
185 }
186
187 static int match_explicit_refs(struct ref *src, struct ref *dst,
188 struct ref ***dst_tail, struct refspec *rs)
189 {
190 int i, errs;
191 for (i = errs = 0; rs[i].src; i++) {
192 struct ref *matched_src, *matched_dst;
193
194 matched_src = matched_dst = NULL;
195 switch (count_refspec_match(rs[i].src, src, &matched_src)) {
196 case 1:
197 break;
198 case 0:
199 /* The source could be in the get_sha1() format
200 * not a reference name.
201 */
202 matched_src = try_explicit_object_name(rs[i].src);
203 if (matched_src)
204 break;
205 errs = 1;
206 error("src refspec %s does not match any.",
207 rs[i].src);
208 break;
209 default:
210 errs = 1;
211 error("src refspec %s matches more than one.",
212 rs[i].src);
213 break;
214 }
215 switch (count_refspec_match(rs[i].dst, dst, &matched_dst)) {
216 case 1:
217 break;
218 case 0:
219 if (!memcmp(rs[i].dst, "refs/", 5)) {
220 int len = strlen(rs[i].dst) + 1;
221 matched_dst = xcalloc(1, sizeof(*dst) + len);
222 memcpy(matched_dst->name, rs[i].dst, len);
223 link_dst_tail(matched_dst, dst_tail);
224 }
225 else if (!strcmp(rs[i].src, rs[i].dst) &&
226 matched_src) {
227 /* pushing "master:master" when
228 * remote does not have master yet.
229 */
230 int len = strlen(matched_src->name) + 1;
231 matched_dst = xcalloc(1, sizeof(*dst) + len);
232 memcpy(matched_dst->name, matched_src->name,
233 len);
234 link_dst_tail(matched_dst, dst_tail);
235 }
236 else {
237 errs = 1;
238 error("dst refspec %s does not match any "
239 "existing ref on the remote and does "
240 "not start with refs/.", rs[i].dst);
241 }
242 break;
243 default:
244 errs = 1;
245 error("dst refspec %s matches more than one.",
246 rs[i].dst);
247 break;
248 }
249 if (errs)
250 continue;
251 if (matched_dst->peer_ref) {
252 errs = 1;
253 error("dst ref %s receives from more than one src.",
254 matched_dst->name);
255 }
256 else {
257 matched_dst->peer_ref = matched_src;
258 matched_dst->force = rs[i].force;
259 }
260 }
261 return -errs;
262 }
263
264 static struct ref *find_ref_by_name(struct ref *list, const char *name)
265 {
266 for ( ; list; list = list->next)
267 if (!strcmp(list->name, name))
268 return list;
269 return NULL;
270 }
271
272 int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
273 int nr_refspec, char **refspec, int all)
274 {
275 struct refspec *rs = parse_ref_spec(nr_refspec, refspec);
276
277 if (nr_refspec)
278 return match_explicit_refs(src, dst, dst_tail, rs);
279
280 /* pick the remainder */
281 for ( ; src; src = src->next) {
282 struct ref *dst_peer;
283 if (src->peer_ref)
284 continue;
285 dst_peer = find_ref_by_name(dst, src->name);
286 if ((dst_peer && dst_peer->peer_ref) || (!dst_peer && !all))
287 continue;
288 if (!dst_peer) {
289 /* Create a new one and link it */
290 int len = strlen(src->name) + 1;
291 dst_peer = xcalloc(1, sizeof(*dst_peer) + len);
292 memcpy(dst_peer->name, src->name, len);
293 memcpy(dst_peer->new_sha1, src->new_sha1, 20);
294 link_dst_tail(dst_peer, dst_tail);
295 }
296 dst_peer->peer_ref = src;
297 }
298 return 0;
299 }
300
301 enum protocol {
302 PROTO_LOCAL = 1,
303 PROTO_SSH,
304 PROTO_GIT,
305 };
306
307 static enum protocol get_protocol(const char *name)
308 {
309 if (!strcmp(name, "ssh"))
310 return PROTO_SSH;
311 if (!strcmp(name, "git"))
312 return PROTO_GIT;
313 if (!strcmp(name, "git+ssh"))
314 return PROTO_SSH;
315 if (!strcmp(name, "ssh+git"))
316 return PROTO_SSH;
317 die("I don't handle protocol '%s'", name);
318 }
319
320 #define STR_(s) # s
321 #define STR(s) STR_(s)
322
323 #ifndef NO_IPV6
324
325 /*
326 * Returns a connected socket() fd, or else die()s.
327 */
328 static int git_tcp_connect_sock(char *host)
329 {
330 int sockfd = -1;
331 char *colon, *end;
332 char *port = STR(DEFAULT_GIT_PORT);
333 struct addrinfo hints, *ai0, *ai;
334 int gai;
335
336 if (host[0] == '[') {
337 end = strchr(host + 1, ']');
338 if (end) {
339 *end = 0;
340 end++;
341 host++;
342 } else
343 end = host;
344 } else
345 end = host;
346 colon = strchr(end, ':');
347
348 if (colon) {
349 *colon = 0;
350 port = colon + 1;
351 }
352
353 memset(&hints, 0, sizeof(hints));
354 hints.ai_socktype = SOCK_STREAM;
355 hints.ai_protocol = IPPROTO_TCP;
356
357 gai = getaddrinfo(host, port, &hints, &ai);
358 if (gai)
359 die("Unable to look up %s (%s)", host, gai_strerror(gai));
360
361 for (ai0 = ai; ai; ai = ai->ai_next) {
362 sockfd = socket(ai->ai_family,
363 ai->ai_socktype, ai->ai_protocol);
364 if (sockfd < 0)
365 continue;
366 if (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
367 close(sockfd);
368 sockfd = -1;
369 continue;
370 }
371 break;
372 }
373
374 freeaddrinfo(ai0);
375
376 if (sockfd < 0)
377 die("unable to connect a socket (%s)", strerror(errno));
378
379 return sockfd;
380 }
381
382 #else /* NO_IPV6 */
383
384 /*
385 * Returns a connected socket() fd, or else die()s.
386 */
387 static int git_tcp_connect_sock(char *host)
388 {
389 int sockfd = -1;
390 char *colon, *end;
391 char *port = STR(DEFAULT_GIT_PORT), *ep;
392 struct hostent *he;
393 struct sockaddr_in sa;
394 char **ap;
395 unsigned int nport;
396
397 if (host[0] == '[') {
398 end = strchr(host + 1, ']');
399 if (end) {
400 *end = 0;
401 end++;
402 host++;
403 } else
404 end = host;
405 } else
406 end = host;
407 colon = strchr(end, ':');
408
409 if (colon) {
410 *colon = 0;
411 port = colon + 1;
412 }
413
414 he = gethostbyname(host);
415 if (!he)
416 die("Unable to look up %s (%s)", host, hstrerror(h_errno));
417 nport = strtoul(port, &ep, 10);
418 if ( ep == port || *ep ) {
419 /* Not numeric */
420 struct servent *se = getservbyname(port,"tcp");
421 if ( !se )
422 die("Unknown port %s\n", port);
423 nport = se->s_port;
424 }
425
426 for (ap = he->h_addr_list; *ap; ap++) {
427 sockfd = socket(he->h_addrtype, SOCK_STREAM, 0);
428 if (sockfd < 0)
429 continue;
430
431 memset(&sa, 0, sizeof sa);
432 sa.sin_family = he->h_addrtype;
433 sa.sin_port = htons(nport);
434 memcpy(&sa.sin_addr, *ap, he->h_length);
435
436 if (connect(sockfd, (struct sockaddr *)&sa, sizeof sa) < 0) {
437 close(sockfd);
438 sockfd = -1;
439 continue;
440 }
441 break;
442 }
443
444 if (sockfd < 0)
445 die("unable to connect a socket (%s)", strerror(errno));
446
447 return sockfd;
448 }
449
450 #endif /* NO_IPV6 */
451
452
453 static void git_tcp_connect(int fd[2],
454 const char *prog, char *host, char *path)
455 {
456 int sockfd = git_tcp_connect_sock(host);
457
458 fd[0] = sockfd;
459 fd[1] = sockfd;
460 }
461
462
463 static char *git_proxy_command = NULL;
464 static const char *rhost_name = NULL;
465 static int rhost_len;
466
467 static int git_proxy_command_options(const char *var, const char *value)
468 {
469 if (!strcmp(var, "core.gitproxy")) {
470 const char *for_pos;
471 int matchlen = -1;
472 int hostlen;
473
474 if (git_proxy_command)
475 return 0;
476 /* [core]
477 * ;# matches www.kernel.org as well
478 * gitproxy = netcatter-1 for kernel.org
479 * gitproxy = netcatter-2 for sample.xz
480 * gitproxy = netcatter-default
481 */
482 for_pos = strstr(value, " for ");
483 if (!for_pos)
484 /* matches everybody */
485 matchlen = strlen(value);
486 else {
487 hostlen = strlen(for_pos + 5);
488 if (rhost_len < hostlen)
489 matchlen = -1;
490 else if (!strncmp(for_pos + 5,
491 rhost_name + rhost_len - hostlen,
492 hostlen) &&
493 ((rhost_len == hostlen) ||
494 rhost_name[rhost_len - hostlen -1] == '.'))
495 matchlen = for_pos - value;
496 else
497 matchlen = -1;
498 }
499 if (0 <= matchlen) {
500 /* core.gitproxy = none for kernel.org */
501 if (matchlen == 4 &&
502 !memcmp(value, "none", 4))
503 matchlen = 0;
504 git_proxy_command = xmalloc(matchlen + 1);
505 memcpy(git_proxy_command, value, matchlen);
506 git_proxy_command[matchlen] = 0;
507 }
508 return 0;
509 }
510
511 return git_default_config(var, value);
512 }
513
514 static int git_use_proxy(const char *host)
515 {
516 rhost_name = host;
517 rhost_len = strlen(host);
518 git_proxy_command = getenv("GIT_PROXY_COMMAND");
519 git_config(git_proxy_command_options);
520 rhost_name = NULL;
521 return (git_proxy_command && *git_proxy_command);
522 }
523
524 static void git_proxy_connect(int fd[2],
525 const char *prog, char *host, char *path)
526 {
527 char *port = STR(DEFAULT_GIT_PORT);
528 char *colon, *end;
529 int pipefd[2][2];
530 pid_t pid;
531
532 if (host[0] == '[') {
533 end = strchr(host + 1, ']');
534 if (end) {
535 *end = 0;
536 end++;
537 host++;
538 } else
539 end = host;
540 } else
541 end = host;
542 colon = strchr(end, ':');
543
544 if (colon) {
545 *colon = 0;
546 port = colon + 1;
547 }
548
549 if (pipe(pipefd[0]) < 0 || pipe(pipefd[1]) < 0)
550 die("unable to create pipe pair for communication");
551 pid = fork();
552 if (!pid) {
553 dup2(pipefd[1][0], 0);
554 dup2(pipefd[0][1], 1);
555 close(pipefd[0][0]);
556 close(pipefd[0][1]);
557 close(pipefd[1][0]);
558 close(pipefd[1][1]);
559 execlp(git_proxy_command, git_proxy_command, host, port, NULL);
560 die("exec failed");
561 }
562 if (pid < 0)
563 die("fork failed");
564 fd[0] = pipefd[0][0];
565 fd[1] = pipefd[1][1];
566 close(pipefd[0][1]);
567 close(pipefd[1][0]);
568 }
569
570 /*
571 * Yeah, yeah, fixme. Need to pass in the heads etc.
572 */
573 int git_connect(int fd[2], char *url, const char *prog)
574 {
575 char command[1024];
576 char *host, *path = url;
577 char *end;
578 int c;
579 int pipefd[2][2];
580 pid_t pid;
581 enum protocol protocol = PROTO_LOCAL;
582 int free_path = 0;
583
584 /* Without this we cannot rely on waitpid() to tell
585 * what happened to our children.
586 */
587 signal(SIGCHLD, SIG_DFL);
588
589 host = strstr(url, "://");
590 if(host) {
591 *host = '\0';
592 protocol = get_protocol(url);
593 host += 3;
594 c = '/';
595 } else {
596 host = url;
597 c = ':';
598 }
599
600 if (host[0] == '[') {
601 end = strchr(host + 1, ']');
602 if (end) {
603 *end = 0;
604 end++;
605 host++;
606 } else
607 end = host;
608 } else
609 end = host;
610
611 path = strchr(end, c);
612 if (c == ':') {
613 if (path) {
614 protocol = PROTO_SSH;
615 *path++ = '\0';
616 } else
617 path = host;
618 }
619
620 if (!path || !*path)
621 die("No path specified. See 'man git-pull' for valid url syntax");
622
623 /*
624 * null-terminate hostname and point path to ~ for URL's like this:
625 * ssh://host.xz/~user/repo
626 */
627 if (protocol != PROTO_LOCAL && host != url) {
628 char *ptr = path;
629 if (path[1] == '~')
630 path++;
631 else {
632 path = strdup(ptr);
633 free_path = 1;
634 }
635
636 *ptr = '\0';
637 }
638
639 if (protocol == PROTO_GIT) {
640 /* These underlying connection commands die() if they
641 * cannot connect.
642 */
643 char *target_host = strdup(host);
644 if (git_use_proxy(host))
645 git_proxy_connect(fd, prog, host, path);
646 else
647 git_tcp_connect(fd, prog, host, path);
648 /*
649 * Separate original protocol components prog and path
650 * from extended components with a NUL byte.
651 */
652 packet_write(fd[1],
653 "%s %s%chost=%s%c",
654 prog, path, 0,
655 target_host, 0);
656 free(target_host);
657 if (free_path)
658 free(path);
659 return 0;
660 }
661
662 if (pipe(pipefd[0]) < 0 || pipe(pipefd[1]) < 0)
663 die("unable to create pipe pair for communication");
664 pid = fork();
665 if (pid < 0)
666 die("unable to fork");
667 if (!pid) {
668 snprintf(command, sizeof(command), "%s %s", prog,
669 sq_quote(path));
670 dup2(pipefd[1][0], 0);
671 dup2(pipefd[0][1], 1);
672 close(pipefd[0][0]);
673 close(pipefd[0][1]);
674 close(pipefd[1][0]);
675 close(pipefd[1][1]);
676 if (protocol == PROTO_SSH) {
677 const char *ssh, *ssh_basename;
678 ssh = getenv("GIT_SSH");
679 if (!ssh) ssh = "ssh";
680 ssh_basename = strrchr(ssh, '/');
681 if (!ssh_basename)
682 ssh_basename = ssh;
683 else
684 ssh_basename++;
685 execlp(ssh, ssh_basename, host, command, NULL);
686 }
687 else {
688 unsetenv(ALTERNATE_DB_ENVIRONMENT);
689 unsetenv(DB_ENVIRONMENT);
690 unsetenv(GIT_DIR_ENVIRONMENT);
691 unsetenv(GRAFT_ENVIRONMENT);
692 unsetenv(INDEX_ENVIRONMENT);
693 execlp("sh", "sh", "-c", command, NULL);
694 }
695 die("exec failed");
696 }
697 fd[0] = pipefd[0][0];
698 fd[1] = pipefd[1][1];
699 close(pipefd[0][1]);
700 close(pipefd[1][0]);
701 if (free_path)
702 free(path);
703 return pid;
704 }
705
706 int finish_connect(pid_t pid)
707 {
708 int ret;
709
710 for (;;) {
711 ret = waitpid(pid, NULL, 0);
712 if (!ret)
713 break;
714 if (errno != EINTR)
715 break;
716 }
717 return ret;
718 }