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 "run-command.h"
7static char *server_capabilities;
9static int check_ref(const char *name, int len, unsigned int flags)
11{
12 if (!flags)
13 return 1;
14 if (len < 5 || memcmp(name, "refs/", 5))
16 return 0;
17 /* Skip the "refs/" part */
19 name += 5;
20 len -= 5;
21 /* REF_NORMAL means that we don't want the magic fake tag refs */
23 if ((flags & REF_NORMAL) && check_ref_format(name) < 0)
24 return 0;
25 /* REF_HEADS means that we want regular branch heads */
27 if ((flags & REF_HEADS) && !memcmp(name, "heads/", 6))
28 return 1;
29 /* REF_TAGS means that we want tags */
31 if ((flags & REF_TAGS) && !memcmp(name, "tags/", 5))
32 return 1;
33 /* All type bits clear means that we are ok with anything */
35 return !(flags & ~REF_NORMAL);
36}
37/*
39 * Read all the refs from the other end
40 */
41struct ref **get_remote_heads(int in, struct ref **list,
42 int nr_match, char **match,
43 unsigned int flags)
44{
45 *list = NULL;
46 for (;;) {
47 struct ref *ref;
48 unsigned char old_sha1[20];
49 static char buffer[1000];
50 char *name;
51 int len, name_len;
52 len = packet_read_line(in, buffer, sizeof(buffer));
54 if (!len)
55 break;
56 if (buffer[len-1] == '\n')
57 buffer[--len] = 0;
58 if (len < 42 || get_sha1_hex(buffer, old_sha1) || buffer[40] != ' ')
60 die("protocol error: expected sha/ref, got '%s'", buffer);
61 name = buffer + 41;
62 name_len = strlen(name);
64 if (len != name_len + 41) {
65 if (server_capabilities)
66 free(server_capabilities);
67 server_capabilities = xstrdup(name + name_len + 1);
68 }
69 if (!check_ref(name, name_len, flags))
71 continue;
72 if (nr_match && !path_match(name, nr_match, match))
73 continue;
74 ref = xcalloc(1, sizeof(*ref) + len - 40);
75 hashcpy(ref->old_sha1, old_sha1);
76 memcpy(ref->name, buffer + 41, len - 40);
77 *list = ref;
78 list = &ref->next;
79 }
80 return list;
81}
82int server_supports(const char *feature)
84{
85 return server_capabilities &&
86 strstr(server_capabilities, feature) != NULL;
87}
88int get_ack(int fd, unsigned char *result_sha1)
90{
91 static char line[1000];
92 int len = packet_read_line(fd, line, sizeof(line));
93 if (!len)
95 die("git-fetch-pack: expected ACK/NAK, got EOF");
96 if (line[len-1] == '\n')
97 line[--len] = 0;
98 if (!strcmp(line, "NAK"))
99 return 0;
100 if (!prefixcmp(line, "ACK ")) {
101 if (!get_sha1_hex(line+4, result_sha1)) {
102 if (strstr(line+45, "continue"))
103 return 2;
104 return 1;
105 }
106 }
107 die("git-fetch_pack: expected ACK/NAK, got '%s'", line);
108}
109int path_match(const char *path, int nr, char **match)
111{
112 int i;
113 int pathlen = strlen(path);
114 for (i = 0; i < nr; i++) {
116 char *s = match[i];
117 int len = strlen(s);
118 if (!len || len > pathlen)
120 continue;
121 if (memcmp(path + pathlen - len, s, len))
122 continue;
123 if (pathlen > len && path[pathlen - len - 1] != '/')
124 continue;
125 *s = 0;
126 return (i + 1);
127 }
128 return 0;
129}
130struct refspec {
132 char *src;
133 char *dst;
134 char force;
135};
136/*
138 * A:B means fast forward remote B with local A.
139 * +A:B means overwrite remote B with local A.
140 * +A is a shorthand for +A:A.
141 * A is a shorthand for A:A.
142 * :B means delete remote B.
143 */
144static struct refspec *parse_ref_spec(int nr_refspec, char **refspec)
145{
146 int i;
147 struct refspec *rs = xcalloc(sizeof(*rs), (nr_refspec + 1));
148 for (i = 0; i < nr_refspec; i++) {
149 char *sp, *dp, *ep;
150 sp = refspec[i];
151 if (*sp == '+') {
152 rs[i].force = 1;
153 sp++;
154 }
155 ep = strchr(sp, ':');
156 if (ep) {
157 dp = ep + 1;
158 *ep = 0;
159 }
160 else
161 dp = sp;
162 rs[i].src = sp;
163 rs[i].dst = dp;
164 }
165 rs[nr_refspec].src = rs[nr_refspec].dst = NULL;
166 return rs;
167}
168static int count_refspec_match(const char *pattern,
170 struct ref *refs,
171 struct ref **matched_ref)
172{
173 int patlen = strlen(pattern);
174 struct ref *matched_weak = NULL;
175 struct ref *matched = NULL;
176 int weak_match = 0;
177 int match = 0;
178 for (weak_match = match = 0; refs; refs = refs->next) {
180 char *name = refs->name;
181 int namelen = strlen(name);
182 int weak_match;
183 if (namelen < patlen ||
185 memcmp(name + namelen - patlen, pattern, patlen))
186 continue;
187 if (namelen != patlen && name[namelen - patlen - 1] != '/')
188 continue;
189 /* A match is "weak" if it is with refs outside
191 * heads or tags, and did not specify the pattern
192 * in full (e.g. "refs/remotes/origin/master") or at
193 * least from the toplevel (e.g. "remotes/origin/master");
194 * otherwise "git push $URL master" would result in
195 * ambiguity between remotes/origin/master and heads/master
196 * at the remote site.
197 */
198 if (namelen != patlen &&
199 patlen != namelen - 5 &&
200 prefixcmp(name, "refs/heads/") &&
201 prefixcmp(name, "refs/tags/")) {
202 /* We want to catch the case where only weak
203 * matches are found and there are multiple
204 * matches, and where more than one strong
205 * matches are found, as ambiguous. One
206 * strong match with zero or more weak matches
207 * are acceptable as a unique match.
208 */
209 matched_weak = refs;
210 weak_match++;
211 }
212 else {
213 matched = refs;
214 match++;
215 }
216 }
217 if (!matched) {
218 *matched_ref = matched_weak;
219 return weak_match;
220 }
221 else {
222 *matched_ref = matched;
223 return match;
224 }
225}
226static void link_dst_tail(struct ref *ref, struct ref ***tail)
228{
229 **tail = ref;
230 *tail = &ref->next;
231 **tail = NULL;
232}
233static struct ref *try_explicit_object_name(const char *name)
235{
236 unsigned char sha1[20];
237 struct ref *ref;
238 int len;
239 if (!*name) {
241 ref = xcalloc(1, sizeof(*ref) + 20);
242 strcpy(ref->name, "(delete)");
243 hashclr(ref->new_sha1);
244 return ref;
245 }
246 if (get_sha1(name, sha1))
247 return NULL;
248 len = strlen(name) + 1;
249 ref = xcalloc(1, sizeof(*ref) + len);
250 memcpy(ref->name, name, len);
251 hashcpy(ref->new_sha1, sha1);
252 return ref;
253}
254static int match_explicit_refs(struct ref *src, struct ref *dst,
256 struct ref ***dst_tail, struct refspec *rs)
257{
258 int i, errs;
259 for (i = errs = 0; rs[i].src; i++) {
260 struct ref *matched_src, *matched_dst;
261 matched_src = matched_dst = NULL;
263 switch (count_refspec_match(rs[i].src, src, &matched_src)) {
264 case 1:
265 break;
266 case 0:
267 /* The source could be in the get_sha1() format
268 * not a reference name. :refs/other is a
269 * way to delete 'other' ref at the remote end.
270 */
271 matched_src = try_explicit_object_name(rs[i].src);
272 if (matched_src)
273 break;
274 errs = 1;
275 error("src refspec %s does not match any.",
276 rs[i].src);
277 break;
278 default:
279 errs = 1;
280 error("src refspec %s matches more than one.",
281 rs[i].src);
282 break;
283 }
284 switch (count_refspec_match(rs[i].dst, dst, &matched_dst)) {
285 case 1:
286 break;
287 case 0:
288 if (!memcmp(rs[i].dst, "refs/", 5)) {
289 int len = strlen(rs[i].dst) + 1;
290 matched_dst = xcalloc(1, sizeof(*dst) + len);
291 memcpy(matched_dst->name, rs[i].dst, len);
292 link_dst_tail(matched_dst, dst_tail);
293 }
294 else if (!strcmp(rs[i].src, rs[i].dst) &&
295 matched_src) {
296 /* pushing "master:master" when
297 * remote does not have master yet.
298 */
299 int len = strlen(matched_src->name) + 1;
300 matched_dst = xcalloc(1, sizeof(*dst) + len);
301 memcpy(matched_dst->name, matched_src->name,
302 len);
303 link_dst_tail(matched_dst, dst_tail);
304 }
305 else {
306 errs = 1;
307 error("dst refspec %s does not match any "
308 "existing ref on the remote and does "
309 "not start with refs/.", rs[i].dst);
310 }
311 break;
312 default:
313 errs = 1;
314 error("dst refspec %s matches more than one.",
315 rs[i].dst);
316 break;
317 }
318 if (errs)
319 continue;
320 if (matched_dst->peer_ref) {
321 errs = 1;
322 error("dst ref %s receives from more than one src.",
323 matched_dst->name);
324 }
325 else {
326 matched_dst->peer_ref = matched_src;
327 matched_dst->force = rs[i].force;
328 }
329 }
330 return -errs;
331}
332static struct ref *find_ref_by_name(struct ref *list, const char *name)
334{
335 for ( ; list; list = list->next)
336 if (!strcmp(list->name, name))
337 return list;
338 return NULL;
339}
340int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
342 int nr_refspec, char **refspec, int all)
343{
344 struct refspec *rs = parse_ref_spec(nr_refspec, refspec);
345 if (nr_refspec)
347 return match_explicit_refs(src, dst, dst_tail, rs);
348 /* pick the remainder */
350 for ( ; src; src = src->next) {
351 struct ref *dst_peer;
352 if (src->peer_ref)
353 continue;
354 dst_peer = find_ref_by_name(dst, src->name);
355 if ((dst_peer && dst_peer->peer_ref) || (!dst_peer && !all))
356 continue;
357 if (!dst_peer) {
358 /* Create a new one and link it */
359 int len = strlen(src->name) + 1;
360 dst_peer = xcalloc(1, sizeof(*dst_peer) + len);
361 memcpy(dst_peer->name, src->name, len);
362 hashcpy(dst_peer->new_sha1, src->new_sha1);
363 link_dst_tail(dst_peer, dst_tail);
364 }
365 dst_peer->peer_ref = src;
366 }
367 return 0;
368}
369enum protocol {
371 PROTO_LOCAL = 1,
372 PROTO_SSH,
373 PROTO_GIT,
374};
375static enum protocol get_protocol(const char *name)
377{
378 if (!strcmp(name, "ssh"))
379 return PROTO_SSH;
380 if (!strcmp(name, "git"))
381 return PROTO_GIT;
382 if (!strcmp(name, "git+ssh"))
383 return PROTO_SSH;
384 if (!strcmp(name, "ssh+git"))
385 return PROTO_SSH;
386 die("I don't handle protocol '%s'", name);
387}
388#define STR_(s) # s
390#define STR(s) STR_(s)
391#ifndef NO_IPV6
393/*
395 * Returns a connected socket() fd, or else die()s.
396 */
397static int git_tcp_connect_sock(char *host, int flags)
398{
399 int sockfd = -1, saved_errno = 0;
400 char *colon, *end;
401 const char *port = STR(DEFAULT_GIT_PORT);
402 struct addrinfo hints, *ai0, *ai;
403 int gai;
404 if (host[0] == '[') {
406 end = strchr(host + 1, ']');
407 if (end) {
408 *end = 0;
409 end++;
410 host++;
411 } else
412 end = host;
413 } else
414 end = host;
415 colon = strchr(end, ':');
416 if (colon) {
418 *colon = 0;
419 port = colon + 1;
420 if (!*port)
421 port = "<none>";
422 }
423 memset(&hints, 0, sizeof(hints));
425 hints.ai_socktype = SOCK_STREAM;
426 hints.ai_protocol = IPPROTO_TCP;
427 if (flags & CONNECT_VERBOSE)
429 fprintf(stderr, "Looking up %s ... ", host);
430 gai = getaddrinfo(host, port, &hints, &ai);
432 if (gai)
433 die("Unable to look up %s (port %s) (%s)", host, port, gai_strerror(gai));
434 if (flags & CONNECT_VERBOSE)
436 fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
437 for (ai0 = ai; ai; ai = ai->ai_next) {
439 sockfd = socket(ai->ai_family,
440 ai->ai_socktype, ai->ai_protocol);
441 if (sockfd < 0) {
442 saved_errno = errno;
443 continue;
444 }
445 if (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
446 saved_errno = errno;
447 close(sockfd);
448 sockfd = -1;
449 continue;
450 }
451 break;
452 }
453 freeaddrinfo(ai0);
455 if (sockfd < 0)
457 die("unable to connect a socket (%s)", strerror(saved_errno));
458 if (flags & CONNECT_VERBOSE)
460 fprintf(stderr, "done.\n");
461 return sockfd;
463}
464#else /* NO_IPV6 */
466/*
468 * Returns a connected socket() fd, or else die()s.
469 */
470static int git_tcp_connect_sock(char *host, int flags)
471{
472 int sockfd = -1, saved_errno = 0;
473 char *colon, *end;
474 char *port = STR(DEFAULT_GIT_PORT), *ep;
475 struct hostent *he;
476 struct sockaddr_in sa;
477 char **ap;
478 unsigned int nport;
479 if (host[0] == '[') {
481 end = strchr(host + 1, ']');
482 if (end) {
483 *end = 0;
484 end++;
485 host++;
486 } else
487 end = host;
488 } else
489 end = host;
490 colon = strchr(end, ':');
491 if (colon) {
493 *colon = 0;
494 port = colon + 1;
495 }
496 if (flags & CONNECT_VERBOSE)
498 fprintf(stderr, "Looking up %s ... ", host);
499 he = gethostbyname(host);
501 if (!he)
502 die("Unable to look up %s (%s)", host, hstrerror(h_errno));
503 nport = strtoul(port, &ep, 10);
504 if ( ep == port || *ep ) {
505 /* Not numeric */
506 struct servent *se = getservbyname(port,"tcp");
507 if ( !se )
508 die("Unknown port %s\n", port);
509 nport = se->s_port;
510 }
511 if (flags & CONNECT_VERBOSE)
513 fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
514 for (ap = he->h_addr_list; *ap; ap++) {
516 sockfd = socket(he->h_addrtype, SOCK_STREAM, 0);
517 if (sockfd < 0) {
518 saved_errno = errno;
519 continue;
520 }
521 memset(&sa, 0, sizeof sa);
523 sa.sin_family = he->h_addrtype;
524 sa.sin_port = htons(nport);
525 memcpy(&sa.sin_addr, *ap, he->h_length);
526 if (connect(sockfd, (struct sockaddr *)&sa, sizeof sa) < 0) {
528 saved_errno = errno;
529 close(sockfd);
530 sockfd = -1;
531 continue;
532 }
533 break;
534 }
535 if (sockfd < 0)
537 die("unable to connect a socket (%s)", strerror(saved_errno));
538 if (flags & CONNECT_VERBOSE)
540 fprintf(stderr, "done.\n");
541 return sockfd;
543}
544#endif /* NO_IPV6 */
546static void git_tcp_connect(int fd[2], char *host, int flags)
549{
550 int sockfd = git_tcp_connect_sock(host, flags);
551 fd[0] = sockfd;
553 fd[1] = dup(sockfd);
554}
555static char *git_proxy_command;
558static const char *rhost_name;
559static int rhost_len;
560static int git_proxy_command_options(const char *var, const char *value)
562{
563 if (!strcmp(var, "core.gitproxy")) {
564 const char *for_pos;
565 int matchlen = -1;
566 int hostlen;
567 if (git_proxy_command)
569 return 0;
570 /* [core]
571 * ;# matches www.kernel.org as well
572 * gitproxy = netcatter-1 for kernel.org
573 * gitproxy = netcatter-2 for sample.xz
574 * gitproxy = netcatter-default
575 */
576 for_pos = strstr(value, " for ");
577 if (!for_pos)
578 /* matches everybody */
579 matchlen = strlen(value);
580 else {
581 hostlen = strlen(for_pos + 5);
582 if (rhost_len < hostlen)
583 matchlen = -1;
584 else if (!strncmp(for_pos + 5,
585 rhost_name + rhost_len - hostlen,
586 hostlen) &&
587 ((rhost_len == hostlen) ||
588 rhost_name[rhost_len - hostlen -1] == '.'))
589 matchlen = for_pos - value;
590 else
591 matchlen = -1;
592 }
593 if (0 <= matchlen) {
594 /* core.gitproxy = none for kernel.org */
595 if (matchlen == 4 &&
596 !memcmp(value, "none", 4))
597 matchlen = 0;
598 git_proxy_command = xmalloc(matchlen + 1);
599 memcpy(git_proxy_command, value, matchlen);
600 git_proxy_command[matchlen] = 0;
601 }
602 return 0;
603 }
604 return git_default_config(var, value);
606}
607static int git_use_proxy(const char *host)
609{
610 rhost_name = host;
611 rhost_len = strlen(host);
612 git_proxy_command = getenv("GIT_PROXY_COMMAND");
613 git_config(git_proxy_command_options);
614 rhost_name = NULL;
615 return (git_proxy_command && *git_proxy_command);
616}
617static void git_proxy_connect(int fd[2], char *host)
619{
620 const char *port = STR(DEFAULT_GIT_PORT);
621 char *colon, *end;
622 const char *argv[4];
623 struct child_process proxy;
624 if (host[0] == '[') {
626 end = strchr(host + 1, ']');
627 if (end) {
628 *end = 0;
629 end++;
630 host++;
631 } else
632 end = host;
633 } else
634 end = host;
635 colon = strchr(end, ':');
636 if (colon) {
638 *colon = 0;
639 port = colon + 1;
640 }
641 argv[0] = git_proxy_command;
643 argv[1] = host;
644 argv[2] = port;
645 argv[3] = NULL;
646 memset(&proxy, 0, sizeof(proxy));
647 proxy.argv = argv;
648 proxy.in = -1;
649 proxy.out = -1;
650 if (start_command(&proxy))
651 die("cannot start proxy %s", argv[0]);
652 fd[0] = proxy.out; /* read from proxy stdout */
653 fd[1] = proxy.in; /* write to proxy stdin */
654}
655#define MAX_CMD_LEN 1024
657/*
659 * This returns 0 if the transport protocol does not need fork(2),
660 * or a process id if it does. Once done, finish the connection
661 * with finish_connect() with the value returned from this function
662 * (it is safe to call finish_connect() with 0 to support the former
663 * case).
664 *
665 * Does not return a negative value on error; it just dies.
666 */
667pid_t git_connect(int fd[2], char *url, const char *prog, int flags)
668{
669 char *host, *path = url;
670 char *end;
671 int c;
672 int pipefd[2][2];
673 pid_t pid;
674 enum protocol protocol = PROTO_LOCAL;
675 int free_path = 0;
676 /* Without this we cannot rely on waitpid() to tell
678 * what happened to our children.
679 */
680 signal(SIGCHLD, SIG_DFL);
681 host = strstr(url, "://");
683 if(host) {
684 *host = '\0';
685 protocol = get_protocol(url);
686 host += 3;
687 c = '/';
688 } else {
689 host = url;
690 c = ':';
691 }
692 if (host[0] == '[') {
694 end = strchr(host + 1, ']');
695 if (end) {
696 *end = 0;
697 end++;
698 host++;
699 } else
700 end = host;
701 } else
702 end = host;
703 path = strchr(end, c);
705 if (c == ':') {
706 if (path) {
707 protocol = PROTO_SSH;
708 *path++ = '\0';
709 } else
710 path = host;
711 }
712 if (!path || !*path)
714 die("No path specified. See 'man git-pull' for valid url syntax");
715 /*
717 * null-terminate hostname and point path to ~ for URL's like this:
718 * ssh://host.xz/~user/repo
719 */
720 if (protocol != PROTO_LOCAL && host != url) {
721 char *ptr = path;
722 if (path[1] == '~')
723 path++;
724 else {
725 path = xstrdup(ptr);
726 free_path = 1;
727 }
728 *ptr = '\0';
730 }
731 if (protocol == PROTO_GIT) {
733 /* These underlying connection commands die() if they
734 * cannot connect.
735 */
736 char *target_host = xstrdup(host);
737 if (git_use_proxy(host))
738 git_proxy_connect(fd, host);
739 else
740 git_tcp_connect(fd, host, flags);
741 /*
742 * Separate original protocol components prog and path
743 * from extended components with a NUL byte.
744 */
745 packet_write(fd[1],
746 "%s %s%chost=%s%c",
747 prog, path, 0,
748 target_host, 0);
749 free(target_host);
750 if (free_path)
751 free(path);
752 return 0;
753 }
754 if (pipe(pipefd[0]) < 0 || pipe(pipefd[1]) < 0)
756 die("unable to create pipe pair for communication");
757 pid = fork();
758 if (pid < 0)
759 die("unable to fork");
760 if (!pid) {
761 char command[MAX_CMD_LEN];
762 char *posn = command;
763 int size = MAX_CMD_LEN;
764 int of = 0;
765 of |= add_to_string(&posn, &size, prog, 0);
767 of |= add_to_string(&posn, &size, " ", 0);
768 of |= add_to_string(&posn, &size, path, 1);
769 if (of)
771 die("command line too long");
772 dup2(pipefd[1][0], 0);
774 dup2(pipefd[0][1], 1);
775 close(pipefd[0][0]);
776 close(pipefd[0][1]);
777 close(pipefd[1][0]);
778 close(pipefd[1][1]);
779 if (protocol == PROTO_SSH) {
780 const char *ssh, *ssh_basename;
781 ssh = getenv("GIT_SSH");
782 if (!ssh) ssh = "ssh";
783 ssh_basename = strrchr(ssh, '/');
784 if (!ssh_basename)
785 ssh_basename = ssh;
786 else
787 ssh_basename++;
788 execlp(ssh, ssh_basename, host, command, NULL);
789 }
790 else {
791 unsetenv(ALTERNATE_DB_ENVIRONMENT);
792 unsetenv(DB_ENVIRONMENT);
793 unsetenv(GIT_DIR_ENVIRONMENT);
794 unsetenv(GRAFT_ENVIRONMENT);
795 unsetenv(INDEX_ENVIRONMENT);
796 execlp("sh", "sh", "-c", command, NULL);
797 }
798 die("exec failed");
799 }
800 fd[0] = pipefd[0][0];
801 fd[1] = pipefd[1][1];
802 close(pipefd[0][1]);
803 close(pipefd[1][0]);
804 if (free_path)
805 free(path);
806 return pid;
807}
808int finish_connect(pid_t pid)
810{
811 if (pid == 0)
812 return 0;
813 while (waitpid(pid, NULL, 0) < 0) {
815 if (errno != EINTR)
816 return -1;
817 }
818 return 0;
819}