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
9static char *server_capabilities;
10
11static 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 */
42struct 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 = xcalloc(1, sizeof(*ref) + len - 40);
76 hashcpy(ref->old_sha1, old_sha1);
77 memcpy(ref->name, buffer + 41, len - 40);
78 *list = ref;
79 list = &ref->next;
80 }
81 return list;
82}
83
84int server_supports(const char *feature)
85{
86 return server_capabilities &&
87 strstr(server_capabilities, feature) != NULL;
88}
89
90int 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
111int 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
132enum protocol {
133 PROTO_LOCAL = 1,
134 PROTO_SSH,
135 PROTO_GIT,
136};
137
138static 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 die("I don't handle protocol '%s'", name);
149}
150
151#define STR_(s) # s
152#define STR(s) STR_(s)
153
154#ifndef NO_IPV6
155
156static const char *ai_name(const struct addrinfo *ai)
157{
158 static char addr[INET_ADDRSTRLEN];
159 if ( AF_INET == ai->ai_family ) {
160 struct sockaddr_in *in;
161 in = (struct sockaddr_in *)ai->ai_addr;
162 inet_ntop(ai->ai_family, &in->sin_addr, addr, sizeof(addr));
163 } else if ( AF_INET6 == ai->ai_family ) {
164 struct sockaddr_in6 *in;
165 in = (struct sockaddr_in6 *)ai->ai_addr;
166 inet_ntop(ai->ai_family, &in->sin6_addr, addr, sizeof(addr));
167 } else {
168 strcpy(addr, "(unknown)");
169 }
170 return addr;
171}
172
173/*
174 * Returns a connected socket() fd, or else die()s.
175 */
176static int git_tcp_connect_sock(char *host, int flags)
177{
178 int sockfd = -1, saved_errno = 0;
179 char *colon, *end;
180 const char *port = STR(DEFAULT_GIT_PORT);
181 struct addrinfo hints, *ai0, *ai;
182 int gai;
183 int cnt = 0;
184
185 if (host[0] == '[') {
186 end = strchr(host + 1, ']');
187 if (end) {
188 *end = 0;
189 end++;
190 host++;
191 } else
192 end = host;
193 } else
194 end = host;
195 colon = strchr(end, ':');
196
197 if (colon) {
198 *colon = 0;
199 port = colon + 1;
200 if (!*port)
201 port = "<none>";
202 }
203
204 memset(&hints, 0, sizeof(hints));
205 hints.ai_socktype = SOCK_STREAM;
206 hints.ai_protocol = IPPROTO_TCP;
207
208 if (flags & CONNECT_VERBOSE)
209 fprintf(stderr, "Looking up %s ... ", host);
210
211 gai = getaddrinfo(host, port, &hints, &ai);
212 if (gai)
213 die("Unable to look up %s (port %s) (%s)", host, port, gai_strerror(gai));
214
215 if (flags & CONNECT_VERBOSE)
216 fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
217
218 for (ai0 = ai; ai; ai = ai->ai_next) {
219 sockfd = socket(ai->ai_family,
220 ai->ai_socktype, ai->ai_protocol);
221 if (sockfd < 0) {
222 saved_errno = errno;
223 continue;
224 }
225 if (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
226 saved_errno = errno;
227 fprintf(stderr, "%s[%d: %s]: errno=%s\n",
228 host,
229 cnt,
230 ai_name(ai),
231 strerror(saved_errno));
232 close(sockfd);
233 sockfd = -1;
234 continue;
235 }
236 if (flags & CONNECT_VERBOSE)
237 fprintf(stderr, "%s ", ai_name(ai));
238 break;
239 }
240
241 freeaddrinfo(ai0);
242
243 if (sockfd < 0)
244 die("unable to connect a socket (%s)", strerror(saved_errno));
245
246 if (flags & CONNECT_VERBOSE)
247 fprintf(stderr, "done.\n");
248
249 return sockfd;
250}
251
252#else /* NO_IPV6 */
253
254/*
255 * Returns a connected socket() fd, or else die()s.
256 */
257static int git_tcp_connect_sock(char *host, int flags)
258{
259 int sockfd = -1, saved_errno = 0;
260 char *colon, *end;
261 char *port = STR(DEFAULT_GIT_PORT), *ep;
262 struct hostent *he;
263 struct sockaddr_in sa;
264 char **ap;
265 unsigned int nport;
266 int cnt;
267
268 if (host[0] == '[') {
269 end = strchr(host + 1, ']');
270 if (end) {
271 *end = 0;
272 end++;
273 host++;
274 } else
275 end = host;
276 } else
277 end = host;
278 colon = strchr(end, ':');
279
280 if (colon) {
281 *colon = 0;
282 port = colon + 1;
283 }
284
285 if (flags & CONNECT_VERBOSE)
286 fprintf(stderr, "Looking up %s ... ", host);
287
288 he = gethostbyname(host);
289 if (!he)
290 die("Unable to look up %s (%s)", host, hstrerror(h_errno));
291 nport = strtoul(port, &ep, 10);
292 if ( ep == port || *ep ) {
293 /* Not numeric */
294 struct servent *se = getservbyname(port,"tcp");
295 if ( !se )
296 die("Unknown port %s\n", port);
297 nport = se->s_port;
298 }
299
300 if (flags & CONNECT_VERBOSE)
301 fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
302
303 for (cnt = 0, ap = he->h_addr_list; *ap; ap++, cnt++) {
304 sockfd = socket(he->h_addrtype, SOCK_STREAM, 0);
305 if (sockfd < 0) {
306 saved_errno = errno;
307 continue;
308 }
309
310 memset(&sa, 0, sizeof sa);
311 sa.sin_family = he->h_addrtype;
312 sa.sin_port = htons(nport);
313 memcpy(&sa.sin_addr, *ap, he->h_length);
314
315 if (connect(sockfd, (struct sockaddr *)&sa, sizeof sa) < 0) {
316 saved_errno = errno;
317 fprintf(stderr, "%s[%d: %s]: errno=%s\n",
318 host,
319 cnt,
320 inet_ntoa(*(struct in_addr *)&sa.sin_addr),
321 strerror(saved_errno));
322 close(sockfd);
323 sockfd = -1;
324 continue;
325 }
326 if (flags & CONNECT_VERBOSE)
327 fprintf(stderr, "%s ",
328 inet_ntoa(*(struct in_addr *)&sa.sin_addr));
329 break;
330 }
331
332 if (sockfd < 0)
333 die("unable to connect a socket (%s)", strerror(saved_errno));
334
335 if (flags & CONNECT_VERBOSE)
336 fprintf(stderr, "done.\n");
337
338 return sockfd;
339}
340
341#endif /* NO_IPV6 */
342
343
344static void git_tcp_connect(int fd[2], char *host, int flags)
345{
346 int sockfd = git_tcp_connect_sock(host, flags);
347
348 fd[0] = sockfd;
349 fd[1] = dup(sockfd);
350}
351
352
353static char *git_proxy_command;
354static const char *rhost_name;
355static int rhost_len;
356
357static int git_proxy_command_options(const char *var, const char *value)
358{
359 if (!strcmp(var, "core.gitproxy")) {
360 const char *for_pos;
361 int matchlen = -1;
362 int hostlen;
363
364 if (git_proxy_command)
365 return 0;
366 /* [core]
367 * ;# matches www.kernel.org as well
368 * gitproxy = netcatter-1 for kernel.org
369 * gitproxy = netcatter-2 for sample.xz
370 * gitproxy = netcatter-default
371 */
372 for_pos = strstr(value, " for ");
373 if (!for_pos)
374 /* matches everybody */
375 matchlen = strlen(value);
376 else {
377 hostlen = strlen(for_pos + 5);
378 if (rhost_len < hostlen)
379 matchlen = -1;
380 else if (!strncmp(for_pos + 5,
381 rhost_name + rhost_len - hostlen,
382 hostlen) &&
383 ((rhost_len == hostlen) ||
384 rhost_name[rhost_len - hostlen -1] == '.'))
385 matchlen = for_pos - value;
386 else
387 matchlen = -1;
388 }
389 if (0 <= matchlen) {
390 /* core.gitproxy = none for kernel.org */
391 if (matchlen == 4 &&
392 !memcmp(value, "none", 4))
393 matchlen = 0;
394 git_proxy_command = xmalloc(matchlen + 1);
395 memcpy(git_proxy_command, value, matchlen);
396 git_proxy_command[matchlen] = 0;
397 }
398 return 0;
399 }
400
401 return git_default_config(var, value);
402}
403
404static 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
414static 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/*
455 * This returns 0 if the transport protocol does not need fork(2),
456 * or a process id if it does. Once done, finish the connection
457 * with finish_connect() with the value returned from this function
458 * (it is safe to call finish_connect() with 0 to support the former
459 * case).
460 *
461 * Does not return a negative value on error; it just dies.
462 */
463pid_t git_connect(int fd[2], char *url, const char *prog, int flags)
464{
465 char *host, *path = url;
466 char *end;
467 int c;
468 int pipefd[2][2];
469 pid_t pid;
470 enum protocol protocol = PROTO_LOCAL;
471 int free_path = 0;
472
473 /* Without this we cannot rely on waitpid() to tell
474 * what happened to our children.
475 */
476 signal(SIGCHLD, SIG_DFL);
477
478 host = strstr(url, "://");
479 if(host) {
480 *host = '\0';
481 protocol = get_protocol(url);
482 host += 3;
483 c = '/';
484 } else {
485 host = url;
486 c = ':';
487 }
488
489 if (host[0] == '[') {
490 end = strchr(host + 1, ']');
491 if (end) {
492 *end = 0;
493 end++;
494 host++;
495 } else
496 end = host;
497 } else
498 end = host;
499
500 path = strchr(end, c);
501 if (c == ':') {
502 if (path) {
503 protocol = PROTO_SSH;
504 *path++ = '\0';
505 } else
506 path = host;
507 }
508
509 if (!path || !*path)
510 die("No path specified. See 'man git-pull' for valid url syntax");
511
512 /*
513 * null-terminate hostname and point path to ~ for URL's like this:
514 * ssh://host.xz/~user/repo
515 */
516 if (protocol != PROTO_LOCAL && host != url) {
517 char *ptr = path;
518 if (path[1] == '~')
519 path++;
520 else {
521 path = xstrdup(ptr);
522 free_path = 1;
523 }
524
525 *ptr = '\0';
526 }
527
528 if (protocol == PROTO_GIT) {
529 /* These underlying connection commands die() if they
530 * cannot connect.
531 */
532 char *target_host = xstrdup(host);
533 if (git_use_proxy(host))
534 git_proxy_connect(fd, host);
535 else
536 git_tcp_connect(fd, host, flags);
537 /*
538 * Separate original protocol components prog and path
539 * from extended components with a NUL byte.
540 */
541 packet_write(fd[1],
542 "%s %s%chost=%s%c",
543 prog, path, 0,
544 target_host, 0);
545 free(target_host);
546 if (free_path)
547 free(path);
548 return 0;
549 }
550
551 if (pipe(pipefd[0]) < 0 || pipe(pipefd[1]) < 0)
552 die("unable to create pipe pair for communication");
553 pid = fork();
554 if (pid < 0)
555 die("unable to fork");
556 if (!pid) {
557 char command[MAX_CMD_LEN];
558 char *posn = command;
559 int size = MAX_CMD_LEN;
560 int of = 0;
561
562 of |= add_to_string(&posn, &size, prog, 0);
563 of |= add_to_string(&posn, &size, " ", 0);
564 of |= add_to_string(&posn, &size, path, 1);
565
566 if (of)
567 die("command line too long");
568
569 dup2(pipefd[1][0], 0);
570 dup2(pipefd[0][1], 1);
571 close(pipefd[0][0]);
572 close(pipefd[0][1]);
573 close(pipefd[1][0]);
574 close(pipefd[1][1]);
575 if (protocol == PROTO_SSH) {
576 const char *ssh, *ssh_basename;
577 ssh = getenv("GIT_SSH");
578 if (!ssh) ssh = "ssh";
579 ssh_basename = strrchr(ssh, '/');
580 if (!ssh_basename)
581 ssh_basename = ssh;
582 else
583 ssh_basename++;
584 execlp(ssh, ssh_basename, host, command, NULL);
585 }
586 else {
587 unsetenv(ALTERNATE_DB_ENVIRONMENT);
588 unsetenv(DB_ENVIRONMENT);
589 unsetenv(GIT_DIR_ENVIRONMENT);
590 unsetenv(GIT_WORK_TREE_ENVIRONMENT);
591 unsetenv(GRAFT_ENVIRONMENT);
592 unsetenv(INDEX_ENVIRONMENT);
593 execlp("sh", "sh", "-c", command, NULL);
594 }
595 die("exec failed");
596 }
597 fd[0] = pipefd[0][0];
598 fd[1] = pipefd[1][1];
599 close(pipefd[0][1]);
600 close(pipefd[1][0]);
601 if (free_path)
602 free(path);
603 return pid;
604}
605
606int finish_connect(pid_t pid)
607{
608 if (pid == 0)
609 return 0;
610
611 while (waitpid(pid, NULL, 0) < 0) {
612 if (errno != EINTR)
613 return -1;
614 }
615 return 0;
616}