Change git_connect() to return a struct child_process instead of a pid_t.
[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 "run-command.h"
7 #include "remote.h"
8
9 static char *server_capabilities;
10
11 static int check_ref(const char *name, int len, unsigned int flags)
12 {
13 if (!flags)
14 return 1;
15
16 if (len < 5 || memcmp(name, "refs/", 5))
17 return 0;
18
19 /* Skip the "refs/" part */
20 name += 5;
21 len -= 5;
22
23 /* REF_NORMAL means that we don't want the magic fake tag refs */
24 if ((flags & REF_NORMAL) && check_ref_format(name) < 0)
25 return 0;
26
27 /* REF_HEADS means that we want regular branch heads */
28 if ((flags & REF_HEADS) && !memcmp(name, "heads/", 6))
29 return 1;
30
31 /* REF_TAGS means that we want tags */
32 if ((flags & REF_TAGS) && !memcmp(name, "tags/", 5))
33 return 1;
34
35 /* All type bits clear means that we are ok with anything */
36 return !(flags & ~REF_NORMAL);
37 }
38
39 /*
40 * Read all the refs from the other end
41 */
42 struct ref **get_remote_heads(int in, struct ref **list,
43 int nr_match, char **match,
44 unsigned int flags)
45 {
46 *list = NULL;
47 for (;;) {
48 struct ref *ref;
49 unsigned char old_sha1[20];
50 static char buffer[1000];
51 char *name;
52 int len, name_len;
53
54 len = packet_read_line(in, buffer, sizeof(buffer));
55 if (!len)
56 break;
57 if (buffer[len-1] == '\n')
58 buffer[--len] = 0;
59
60 if (len < 42 || get_sha1_hex(buffer, old_sha1) || buffer[40] != ' ')
61 die("protocol error: expected sha/ref, got '%s'", buffer);
62 name = buffer + 41;
63
64 name_len = strlen(name);
65 if (len != name_len + 41) {
66 if (server_capabilities)
67 free(server_capabilities);
68 server_capabilities = xstrdup(name + name_len + 1);
69 }
70
71 if (!check_ref(name, name_len, flags))
72 continue;
73 if (nr_match && !path_match(name, nr_match, match))
74 continue;
75 ref = alloc_ref(name_len + 1);
76 hashcpy(ref->old_sha1, old_sha1);
77 memcpy(ref->name, buffer + 41, name_len + 1);
78 *list = ref;
79 list = &ref->next;
80 }
81 return list;
82 }
83
84 int server_supports(const char *feature)
85 {
86 return server_capabilities &&
87 strstr(server_capabilities, feature) != NULL;
88 }
89
90 int get_ack(int fd, unsigned char *result_sha1)
91 {
92 static char line[1000];
93 int len = packet_read_line(fd, line, sizeof(line));
94
95 if (!len)
96 die("git-fetch-pack: expected ACK/NAK, got EOF");
97 if (line[len-1] == '\n')
98 line[--len] = 0;
99 if (!strcmp(line, "NAK"))
100 return 0;
101 if (!prefixcmp(line, "ACK ")) {
102 if (!get_sha1_hex(line+4, result_sha1)) {
103 if (strstr(line+45, "continue"))
104 return 2;
105 return 1;
106 }
107 }
108 die("git-fetch_pack: expected ACK/NAK, got '%s'", line);
109 }
110
111 int path_match(const char *path, int nr, char **match)
112 {
113 int i;
114 int pathlen = strlen(path);
115
116 for (i = 0; i < nr; i++) {
117 char *s = match[i];
118 int len = strlen(s);
119
120 if (!len || len > pathlen)
121 continue;
122 if (memcmp(path + pathlen - len, s, len))
123 continue;
124 if (pathlen > len && path[pathlen - len - 1] != '/')
125 continue;
126 *s = 0;
127 return (i + 1);
128 }
129 return 0;
130 }
131
132 enum protocol {
133 PROTO_LOCAL = 1,
134 PROTO_SSH,
135 PROTO_GIT,
136 };
137
138 static enum protocol get_protocol(const char *name)
139 {
140 if (!strcmp(name, "ssh"))
141 return PROTO_SSH;
142 if (!strcmp(name, "git"))
143 return PROTO_GIT;
144 if (!strcmp(name, "git+ssh"))
145 return PROTO_SSH;
146 if (!strcmp(name, "ssh+git"))
147 return PROTO_SSH;
148 if (!strcmp(name, "file"))
149 return PROTO_LOCAL;
150 die("I don't handle protocol '%s'", name);
151 }
152
153 #define STR_(s) # s
154 #define STR(s) STR_(s)
155
156 #ifndef NO_IPV6
157
158 static const char *ai_name(const struct addrinfo *ai)
159 {
160 static char addr[INET_ADDRSTRLEN];
161 if ( AF_INET == ai->ai_family ) {
162 struct sockaddr_in *in;
163 in = (struct sockaddr_in *)ai->ai_addr;
164 inet_ntop(ai->ai_family, &in->sin_addr, addr, sizeof(addr));
165 } else if ( AF_INET6 == ai->ai_family ) {
166 struct sockaddr_in6 *in;
167 in = (struct sockaddr_in6 *)ai->ai_addr;
168 inet_ntop(ai->ai_family, &in->sin6_addr, addr, sizeof(addr));
169 } else {
170 strcpy(addr, "(unknown)");
171 }
172 return addr;
173 }
174
175 /*
176 * Returns a connected socket() fd, or else die()s.
177 */
178 static int git_tcp_connect_sock(char *host, int flags)
179 {
180 int sockfd = -1, saved_errno = 0;
181 char *colon, *end;
182 const char *port = STR(DEFAULT_GIT_PORT);
183 struct addrinfo hints, *ai0, *ai;
184 int gai;
185 int cnt = 0;
186
187 if (host[0] == '[') {
188 end = strchr(host + 1, ']');
189 if (end) {
190 *end = 0;
191 end++;
192 host++;
193 } else
194 end = host;
195 } else
196 end = host;
197 colon = strchr(end, ':');
198
199 if (colon) {
200 *colon = 0;
201 port = colon + 1;
202 if (!*port)
203 port = "<none>";
204 }
205
206 memset(&hints, 0, sizeof(hints));
207 hints.ai_socktype = SOCK_STREAM;
208 hints.ai_protocol = IPPROTO_TCP;
209
210 if (flags & CONNECT_VERBOSE)
211 fprintf(stderr, "Looking up %s ... ", host);
212
213 gai = getaddrinfo(host, port, &hints, &ai);
214 if (gai)
215 die("Unable to look up %s (port %s) (%s)", host, port, gai_strerror(gai));
216
217 if (flags & CONNECT_VERBOSE)
218 fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
219
220 for (ai0 = ai; ai; ai = ai->ai_next) {
221 sockfd = socket(ai->ai_family,
222 ai->ai_socktype, ai->ai_protocol);
223 if (sockfd < 0) {
224 saved_errno = errno;
225 continue;
226 }
227 if (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
228 saved_errno = errno;
229 fprintf(stderr, "%s[%d: %s]: errno=%s\n",
230 host,
231 cnt,
232 ai_name(ai),
233 strerror(saved_errno));
234 close(sockfd);
235 sockfd = -1;
236 continue;
237 }
238 if (flags & CONNECT_VERBOSE)
239 fprintf(stderr, "%s ", ai_name(ai));
240 break;
241 }
242
243 freeaddrinfo(ai0);
244
245 if (sockfd < 0)
246 die("unable to connect a socket (%s)", strerror(saved_errno));
247
248 if (flags & CONNECT_VERBOSE)
249 fprintf(stderr, "done.\n");
250
251 return sockfd;
252 }
253
254 #else /* NO_IPV6 */
255
256 /*
257 * Returns a connected socket() fd, or else die()s.
258 */
259 static int git_tcp_connect_sock(char *host, int flags)
260 {
261 int sockfd = -1, saved_errno = 0;
262 char *colon, *end;
263 char *port = STR(DEFAULT_GIT_PORT), *ep;
264 struct hostent *he;
265 struct sockaddr_in sa;
266 char **ap;
267 unsigned int nport;
268 int cnt;
269
270 if (host[0] == '[') {
271 end = strchr(host + 1, ']');
272 if (end) {
273 *end = 0;
274 end++;
275 host++;
276 } else
277 end = host;
278 } else
279 end = host;
280 colon = strchr(end, ':');
281
282 if (colon) {
283 *colon = 0;
284 port = colon + 1;
285 }
286
287 if (flags & CONNECT_VERBOSE)
288 fprintf(stderr, "Looking up %s ... ", host);
289
290 he = gethostbyname(host);
291 if (!he)
292 die("Unable to look up %s (%s)", host, hstrerror(h_errno));
293 nport = strtoul(port, &ep, 10);
294 if ( ep == port || *ep ) {
295 /* Not numeric */
296 struct servent *se = getservbyname(port,"tcp");
297 if ( !se )
298 die("Unknown port %s\n", port);
299 nport = se->s_port;
300 }
301
302 if (flags & CONNECT_VERBOSE)
303 fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
304
305 for (cnt = 0, ap = he->h_addr_list; *ap; ap++, cnt++) {
306 sockfd = socket(he->h_addrtype, SOCK_STREAM, 0);
307 if (sockfd < 0) {
308 saved_errno = errno;
309 continue;
310 }
311
312 memset(&sa, 0, sizeof sa);
313 sa.sin_family = he->h_addrtype;
314 sa.sin_port = htons(nport);
315 memcpy(&sa.sin_addr, *ap, he->h_length);
316
317 if (connect(sockfd, (struct sockaddr *)&sa, sizeof sa) < 0) {
318 saved_errno = errno;
319 fprintf(stderr, "%s[%d: %s]: errno=%s\n",
320 host,
321 cnt,
322 inet_ntoa(*(struct in_addr *)&sa.sin_addr),
323 strerror(saved_errno));
324 close(sockfd);
325 sockfd = -1;
326 continue;
327 }
328 if (flags & CONNECT_VERBOSE)
329 fprintf(stderr, "%s ",
330 inet_ntoa(*(struct in_addr *)&sa.sin_addr));
331 break;
332 }
333
334 if (sockfd < 0)
335 die("unable to connect a socket (%s)", strerror(saved_errno));
336
337 if (flags & CONNECT_VERBOSE)
338 fprintf(stderr, "done.\n");
339
340 return sockfd;
341 }
342
343 #endif /* NO_IPV6 */
344
345
346 static void git_tcp_connect(int fd[2], char *host, int flags)
347 {
348 int sockfd = git_tcp_connect_sock(host, flags);
349
350 fd[0] = sockfd;
351 fd[1] = dup(sockfd);
352 }
353
354
355 static char *git_proxy_command;
356 static const char *rhost_name;
357 static int rhost_len;
358
359 static int git_proxy_command_options(const char *var, const char *value)
360 {
361 if (!strcmp(var, "core.gitproxy")) {
362 const char *for_pos;
363 int matchlen = -1;
364 int hostlen;
365
366 if (git_proxy_command)
367 return 0;
368 /* [core]
369 * ;# matches www.kernel.org as well
370 * gitproxy = netcatter-1 for kernel.org
371 * gitproxy = netcatter-2 for sample.xz
372 * gitproxy = netcatter-default
373 */
374 for_pos = strstr(value, " for ");
375 if (!for_pos)
376 /* matches everybody */
377 matchlen = strlen(value);
378 else {
379 hostlen = strlen(for_pos + 5);
380 if (rhost_len < hostlen)
381 matchlen = -1;
382 else if (!strncmp(for_pos + 5,
383 rhost_name + rhost_len - hostlen,
384 hostlen) &&
385 ((rhost_len == hostlen) ||
386 rhost_name[rhost_len - hostlen -1] == '.'))
387 matchlen = for_pos - value;
388 else
389 matchlen = -1;
390 }
391 if (0 <= matchlen) {
392 /* core.gitproxy = none for kernel.org */
393 if (matchlen == 4 &&
394 !memcmp(value, "none", 4))
395 matchlen = 0;
396 git_proxy_command = xmemdupz(value, matchlen);
397 }
398 return 0;
399 }
400
401 return git_default_config(var, value);
402 }
403
404 static int git_use_proxy(const char *host)
405 {
406 rhost_name = host;
407 rhost_len = strlen(host);
408 git_proxy_command = getenv("GIT_PROXY_COMMAND");
409 git_config(git_proxy_command_options);
410 rhost_name = NULL;
411 return (git_proxy_command && *git_proxy_command);
412 }
413
414 static void git_proxy_connect(int fd[2], char *host)
415 {
416 const char *port = STR(DEFAULT_GIT_PORT);
417 char *colon, *end;
418 const char *argv[4];
419 struct child_process proxy;
420
421 if (host[0] == '[') {
422 end = strchr(host + 1, ']');
423 if (end) {
424 *end = 0;
425 end++;
426 host++;
427 } else
428 end = host;
429 } else
430 end = host;
431 colon = strchr(end, ':');
432
433 if (colon) {
434 *colon = 0;
435 port = colon + 1;
436 }
437
438 argv[0] = git_proxy_command;
439 argv[1] = host;
440 argv[2] = port;
441 argv[3] = NULL;
442 memset(&proxy, 0, sizeof(proxy));
443 proxy.argv = argv;
444 proxy.in = -1;
445 proxy.out = -1;
446 if (start_command(&proxy))
447 die("cannot start proxy %s", argv[0]);
448 fd[0] = proxy.out; /* read from proxy stdout */
449 fd[1] = proxy.in; /* write to proxy stdin */
450 }
451
452 #define MAX_CMD_LEN 1024
453
454 char *get_port(char *host)
455 {
456 char *end;
457 char *p = strchr(host, ':');
458
459 if (p) {
460 strtol(p+1, &end, 10);
461 if (*end == '\0') {
462 *p = '\0';
463 return p+1;
464 }
465 }
466
467 return NULL;
468 }
469
470 /*
471 * This returns NULL if the transport protocol does not need fork(2), or a
472 * struct child_process object if it does. Once done, finish the connection
473 * with finish_connect() with the value returned from this function
474 * (it is safe to call finish_connect() with NULL to support the former
475 * case).
476 *
477 * If it returns, the connect is successful; it just dies on errors.
478 */
479 struct child_process *git_connect(int fd[2], char *url,
480 const char *prog, int flags)
481 {
482 char *host, *path = url;
483 char *end;
484 int c;
485 int pipefd[2][2];
486 struct child_process *conn;
487 enum protocol protocol = PROTO_LOCAL;
488 int free_path = 0;
489 char *port = NULL;
490
491 /* Without this we cannot rely on waitpid() to tell
492 * what happened to our children.
493 */
494 signal(SIGCHLD, SIG_DFL);
495
496 host = strstr(url, "://");
497 if(host) {
498 *host = '\0';
499 protocol = get_protocol(url);
500 host += 3;
501 c = '/';
502 } else {
503 host = url;
504 c = ':';
505 }
506
507 if (host[0] == '[') {
508 end = strchr(host + 1, ']');
509 if (end) {
510 *end = 0;
511 end++;
512 host++;
513 } else
514 end = host;
515 } else
516 end = host;
517
518 path = strchr(end, c);
519 if (path) {
520 if (c == ':') {
521 protocol = PROTO_SSH;
522 *path++ = '\0';
523 }
524 } else
525 path = end;
526
527 if (!path || !*path)
528 die("No path specified. See 'man git-pull' for valid url syntax");
529
530 /*
531 * null-terminate hostname and point path to ~ for URL's like this:
532 * ssh://host.xz/~user/repo
533 */
534 if (protocol != PROTO_LOCAL && host != url) {
535 char *ptr = path;
536 if (path[1] == '~')
537 path++;
538 else {
539 path = xstrdup(ptr);
540 free_path = 1;
541 }
542
543 *ptr = '\0';
544 }
545
546 /*
547 * Add support for ssh port: ssh://host.xy:<port>/...
548 */
549 if (protocol == PROTO_SSH && host != url)
550 port = get_port(host);
551
552 if (protocol == PROTO_GIT) {
553 /* These underlying connection commands die() if they
554 * cannot connect.
555 */
556 char *target_host = xstrdup(host);
557 if (git_use_proxy(host))
558 git_proxy_connect(fd, host);
559 else
560 git_tcp_connect(fd, host, flags);
561 /*
562 * Separate original protocol components prog and path
563 * from extended components with a NUL byte.
564 */
565 packet_write(fd[1],
566 "%s %s%chost=%s%c",
567 prog, path, 0,
568 target_host, 0);
569 free(target_host);
570 if (free_path)
571 free(path);
572 return NULL;
573 }
574
575 if (pipe(pipefd[0]) < 0 || pipe(pipefd[1]) < 0)
576 die("unable to create pipe pair for communication");
577 conn = xcalloc(1, sizeof(*conn));
578 conn->pid = fork();
579 if (conn->pid < 0)
580 die("unable to fork");
581 if (!conn->pid) {
582 struct strbuf cmd;
583
584 strbuf_init(&cmd, MAX_CMD_LEN);
585 strbuf_addstr(&cmd, prog);
586 strbuf_addch(&cmd, ' ');
587 sq_quote_buf(&cmd, path);
588 if (cmd.len >= MAX_CMD_LEN)
589 die("command line too long");
590
591 dup2(pipefd[1][0], 0);
592 dup2(pipefd[0][1], 1);
593 close(pipefd[0][0]);
594 close(pipefd[0][1]);
595 close(pipefd[1][0]);
596 close(pipefd[1][1]);
597 if (protocol == PROTO_SSH) {
598 const char *ssh, *ssh_basename;
599 ssh = getenv("GIT_SSH");
600 if (!ssh) ssh = "ssh";
601 ssh_basename = strrchr(ssh, '/');
602 if (!ssh_basename)
603 ssh_basename = ssh;
604 else
605 ssh_basename++;
606
607 if (!port)
608 execlp(ssh, ssh_basename, host, cmd.buf, NULL);
609 else
610 execlp(ssh, ssh_basename, "-p", port, host,
611 cmd.buf, NULL);
612 }
613 else {
614 unsetenv(ALTERNATE_DB_ENVIRONMENT);
615 unsetenv(DB_ENVIRONMENT);
616 unsetenv(GIT_DIR_ENVIRONMENT);
617 unsetenv(GIT_WORK_TREE_ENVIRONMENT);
618 unsetenv(GRAFT_ENVIRONMENT);
619 unsetenv(INDEX_ENVIRONMENT);
620 execlp("sh", "sh", "-c", cmd.buf, NULL);
621 }
622 die("exec failed");
623 }
624 fd[0] = pipefd[0][0];
625 fd[1] = pipefd[1][1];
626 close(pipefd[0][1]);
627 close(pipefd[1][0]);
628 if (free_path)
629 free(path);
630 return conn;
631 }
632
633 int finish_connect(struct child_process *conn)
634 {
635 if (!conn)
636 return 0;
637
638 while (waitpid(conn->pid, NULL, 0) < 0) {
639 if (errno != EINTR)
640 return -1;
641 }
642 free(conn);
643 return 0;
644 }