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
12static char *server_capabilities = NULL;
13
14/*
15 * Read all the refs from the other end
16 */
17struct 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
60int server_supports(const char *feature)
61{
62 return server_capabilities &&
63 strstr(server_capabilities, feature) != NULL;
64}
65
66int 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
87int 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
108struct 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 */
120static 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
145static 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
166static void link_dst_tail(struct ref *ref, struct ref ***tail)
167{
168 **tail = ref;
169 *tail = &ref->next;
170 **tail = NULL;
171}
172
173static 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
187static 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
264static 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
272int 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
301enum protocol {
302 PROTO_LOCAL = 1,
303 PROTO_SSH,
304 PROTO_GIT,
305};
306
307static 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
325static int git_tcp_connect(int fd[2], const char *prog, char *host, char *path)
326{
327 int sockfd = -1;
328 char *colon, *end;
329 char *port = STR(DEFAULT_GIT_PORT);
330 struct addrinfo hints, *ai0, *ai;
331 int gai;
332
333 if (host[0] == '[') {
334 end = strchr(host + 1, ']');
335 if (end) {
336 *end = 0;
337 end++;
338 host++;
339 } else
340 end = host;
341 } else
342 end = host;
343 colon = strchr(end, ':');
344
345 if (colon) {
346 *colon = 0;
347 port = colon + 1;
348 }
349
350 memset(&hints, 0, sizeof(hints));
351 hints.ai_socktype = SOCK_STREAM;
352 hints.ai_protocol = IPPROTO_TCP;
353
354 gai = getaddrinfo(host, port, &hints, &ai);
355 if (gai)
356 die("Unable to look up %s (%s)", host, gai_strerror(gai));
357
358 for (ai0 = ai; ai; ai = ai->ai_next) {
359 sockfd = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
360 if (sockfd < 0)
361 continue;
362 if (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
363 close(sockfd);
364 sockfd = -1;
365 continue;
366 }
367 break;
368 }
369
370 freeaddrinfo(ai0);
371
372 if (sockfd < 0)
373 die("unable to connect a socket (%s)", strerror(errno));
374
375 fd[0] = sockfd;
376 fd[1] = sockfd;
377 packet_write(sockfd, "%s %s\n", prog, path);
378 return 0;
379}
380
381#else /* NO_IPV6 */
382
383static int git_tcp_connect(int fd[2], const char *prog, char *host, char *path)
384{
385 int sockfd = -1;
386 char *colon, *end;
387 char *port = STR(DEFAULT_GIT_PORT), *ep;
388 struct hostent *he;
389 struct sockaddr_in sa;
390 char **ap;
391 unsigned int nport;
392
393 if (host[0] == '[') {
394 end = strchr(host + 1, ']');
395 if (end) {
396 *end = 0;
397 end++;
398 host++;
399 } else
400 end = host;
401 } else
402 end = host;
403 colon = strchr(end, ':');
404
405 if (colon) {
406 *colon = 0;
407 port = colon + 1;
408 }
409
410
411 he = gethostbyname(host);
412 if (!he)
413 die("Unable to look up %s (%s)", host, hstrerror(h_errno));
414 nport = strtoul(port, &ep, 10);
415 if ( ep == port || *ep ) {
416 /* Not numeric */
417 struct servent *se = getservbyname(port,"tcp");
418 if ( !se )
419 die("Unknown port %s\n", port);
420 nport = se->s_port;
421 }
422
423 for (ap = he->h_addr_list; *ap; ap++) {
424 sockfd = socket(he->h_addrtype, SOCK_STREAM, 0);
425 if (sockfd < 0)
426 continue;
427
428 memset(&sa, 0, sizeof sa);
429 sa.sin_family = he->h_addrtype;
430 sa.sin_port = htons(nport);
431 memcpy(&sa.sin_addr, *ap, he->h_length);
432
433 if (connect(sockfd, (struct sockaddr *)&sa, sizeof sa) < 0) {
434 close(sockfd);
435 sockfd = -1;
436 continue;
437 }
438 break;
439 }
440
441 if (sockfd < 0)
442 die("unable to connect a socket (%s)", strerror(errno));
443
444 fd[0] = sockfd;
445 fd[1] = sockfd;
446 packet_write(sockfd, "%s %s\n", prog, path);
447 return 0;
448}
449
450#endif /* NO_IPV6 */
451
452static char *git_proxy_command = NULL;
453static const char *rhost_name = NULL;
454static int rhost_len;
455
456static int git_proxy_command_options(const char *var, const char *value)
457{
458 if (!strcmp(var, "core.gitproxy")) {
459 const char *for_pos;
460 int matchlen = -1;
461 int hostlen;
462
463 if (git_proxy_command)
464 return 0;
465 /* [core]
466 * ;# matches www.kernel.org as well
467 * gitproxy = netcatter-1 for kernel.org
468 * gitproxy = netcatter-2 for sample.xz
469 * gitproxy = netcatter-default
470 */
471 for_pos = strstr(value, " for ");
472 if (!for_pos)
473 /* matches everybody */
474 matchlen = strlen(value);
475 else {
476 hostlen = strlen(for_pos + 5);
477 if (rhost_len < hostlen)
478 matchlen = -1;
479 else if (!strncmp(for_pos + 5,
480 rhost_name + rhost_len - hostlen,
481 hostlen) &&
482 ((rhost_len == hostlen) ||
483 rhost_name[rhost_len - hostlen -1] == '.'))
484 matchlen = for_pos - value;
485 else
486 matchlen = -1;
487 }
488 if (0 <= matchlen) {
489 /* core.gitproxy = none for kernel.org */
490 if (matchlen == 4 &&
491 !memcmp(value, "none", 4))
492 matchlen = 0;
493 git_proxy_command = xmalloc(matchlen + 1);
494 memcpy(git_proxy_command, value, matchlen);
495 git_proxy_command[matchlen] = 0;
496 }
497 return 0;
498 }
499
500 return git_default_config(var, value);
501}
502
503static int git_use_proxy(const char *host)
504{
505 rhost_name = host;
506 rhost_len = strlen(host);
507 git_proxy_command = getenv("GIT_PROXY_COMMAND");
508 git_config(git_proxy_command_options);
509 rhost_name = NULL;
510 return (git_proxy_command && *git_proxy_command);
511}
512
513static int git_proxy_connect(int fd[2], const char *prog, char *host, char *path)
514{
515 char *port = STR(DEFAULT_GIT_PORT);
516 char *colon, *end;
517 int pipefd[2][2];
518 pid_t pid;
519
520 if (host[0] == '[') {
521 end = strchr(host + 1, ']');
522 if (end) {
523 *end = 0;
524 end++;
525 host++;
526 } else
527 end = host;
528 } else
529 end = host;
530 colon = strchr(end, ':');
531
532 if (colon) {
533 *colon = 0;
534 port = colon + 1;
535 }
536
537 if (pipe(pipefd[0]) < 0 || pipe(pipefd[1]) < 0)
538 die("unable to create pipe pair for communication");
539 pid = fork();
540 if (!pid) {
541 dup2(pipefd[1][0], 0);
542 dup2(pipefd[0][1], 1);
543 close(pipefd[0][0]);
544 close(pipefd[0][1]);
545 close(pipefd[1][0]);
546 close(pipefd[1][1]);
547 execlp(git_proxy_command, git_proxy_command, host, port, NULL);
548 die("exec failed");
549 }
550 fd[0] = pipefd[0][0];
551 fd[1] = pipefd[1][1];
552 close(pipefd[0][1]);
553 close(pipefd[1][0]);
554 packet_write(fd[1], "%s %s\n", prog, path);
555 return pid;
556}
557
558/*
559 * Yeah, yeah, fixme. Need to pass in the heads etc.
560 */
561int git_connect(int fd[2], char *url, const char *prog)
562{
563 char command[1024];
564 char *host, *path = url;
565 char *end;
566 int c;
567 int pipefd[2][2];
568 pid_t pid;
569 enum protocol protocol = PROTO_LOCAL;
570 int free_path = 0;
571
572 host = strstr(url, "://");
573 if(host) {
574 *host = '\0';
575 protocol = get_protocol(url);
576 host += 3;
577 c = '/';
578 } else {
579 host = url;
580 c = ':';
581 }
582
583 if (host[0] == '[') {
584 end = strchr(host + 1, ']');
585 if (end) {
586 *end = 0;
587 end++;
588 host++;
589 } else
590 end = host;
591 } else
592 end = host;
593
594 path = strchr(end, c);
595 if (c == ':') {
596 if (path) {
597 protocol = PROTO_SSH;
598 *path++ = '\0';
599 } else
600 path = host;
601 }
602
603 if (!path || !*path)
604 die("No path specified. See 'man git-pull' for valid url syntax");
605
606 /*
607 * null-terminate hostname and point path to ~ for URL's like this:
608 * ssh://host.xz/~user/repo
609 */
610 if (protocol != PROTO_LOCAL && host != url) {
611 char *ptr = path;
612 if (path[1] == '~')
613 path++;
614 else {
615 path = strdup(ptr);
616 free_path = 1;
617 }
618
619 *ptr = '\0';
620 }
621
622 if (protocol == PROTO_GIT) {
623 int ret;
624 if (git_use_proxy(host))
625 ret = git_proxy_connect(fd, prog, host, path);
626 else
627 ret = git_tcp_connect(fd, prog, host, path);
628 if (free_path)
629 free(path);
630 return ret;
631 }
632
633 if (pipe(pipefd[0]) < 0 || pipe(pipefd[1]) < 0)
634 die("unable to create pipe pair for communication");
635 pid = fork();
636 if (!pid) {
637 snprintf(command, sizeof(command), "%s %s", prog,
638 sq_quote(path));
639 dup2(pipefd[1][0], 0);
640 dup2(pipefd[0][1], 1);
641 close(pipefd[0][0]);
642 close(pipefd[0][1]);
643 close(pipefd[1][0]);
644 close(pipefd[1][1]);
645 if (protocol == PROTO_SSH) {
646 const char *ssh, *ssh_basename;
647 ssh = getenv("GIT_SSH");
648 if (!ssh) ssh = "ssh";
649 ssh_basename = strrchr(ssh, '/');
650 if (!ssh_basename)
651 ssh_basename = ssh;
652 else
653 ssh_basename++;
654 execlp(ssh, ssh_basename, host, command, NULL);
655 }
656 else {
657 unsetenv(ALTERNATE_DB_ENVIRONMENT);
658 unsetenv(DB_ENVIRONMENT);
659 unsetenv(GIT_DIR_ENVIRONMENT);
660 unsetenv(GRAFT_ENVIRONMENT);
661 unsetenv(INDEX_ENVIRONMENT);
662 execlp("sh", "sh", "-c", command, NULL);
663 }
664 die("exec failed");
665 }
666 fd[0] = pipefd[0][0];
667 fd[1] = pipefd[1][1];
668 close(pipefd[0][1]);
669 close(pipefd[1][0]);
670 if (free_path)
671 free(path);
672 return pid;
673}
674
675int finish_connect(pid_t pid)
676{
677 int ret;
678
679 for (;;) {
680 ret = waitpid(pid, NULL, 0);
681 if (!ret)
682 break;
683 if (errno != EINTR)
684 break;
685 }
686 return ret;
687}