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#include "connect.h"
9#include "url.h"
10#include "string-list.h"
11
12static char *server_capabilities;
13static const char *parse_feature_value(const char *, const char *, int *);
14
15static int check_ref(const char *name, int len, unsigned int flags)
16{
17 if (!flags)
18 return 1;
19
20 if (len < 5 || memcmp(name, "refs/", 5))
21 return 0;
22
23 /* Skip the "refs/" part */
24 name += 5;
25 len -= 5;
26
27 /* REF_NORMAL means that we don't want the magic fake tag refs */
28 if ((flags & REF_NORMAL) && check_refname_format(name, 0))
29 return 0;
30
31 /* REF_HEADS means that we want regular branch heads */
32 if ((flags & REF_HEADS) && !memcmp(name, "heads/", 6))
33 return 1;
34
35 /* REF_TAGS means that we want tags */
36 if ((flags & REF_TAGS) && !memcmp(name, "tags/", 5))
37 return 1;
38
39 /* All type bits clear means that we are ok with anything */
40 return !(flags & ~REF_NORMAL);
41}
42
43int check_ref_type(const struct ref *ref, int flags)
44{
45 return check_ref(ref->name, strlen(ref->name), flags);
46}
47
48static void add_extra_have(struct extra_have_objects *extra, unsigned char *sha1)
49{
50 ALLOC_GROW(extra->array, extra->nr + 1, extra->alloc);
51 hashcpy(&(extra->array[extra->nr][0]), sha1);
52 extra->nr++;
53}
54
55static void die_initial_contact(int got_at_least_one_head)
56{
57 if (got_at_least_one_head)
58 die("The remote end hung up upon initial contact");
59 else
60 die("Could not read from remote repository.\n\n"
61 "Please make sure you have the correct access rights\n"
62 "and the repository exists.");
63}
64
65static void parse_one_symref_info(struct string_list *symref, const char *val, int len)
66{
67 char *sym, *target;
68 struct string_list_item *item;
69
70 if (!len)
71 return; /* just "symref" */
72 /* e.g. "symref=HEAD:refs/heads/master" */
73 sym = xmalloc(len + 1);
74 memcpy(sym, val, len);
75 sym[len] = '\0';
76 target = strchr(sym, ':');
77 if (!target)
78 /* just "symref=something" */
79 goto reject;
80 *(target++) = '\0';
81 if (check_refname_format(sym, REFNAME_ALLOW_ONELEVEL) ||
82 check_refname_format(target, REFNAME_ALLOW_ONELEVEL))
83 /* "symref=bogus:pair */
84 goto reject;
85 item = string_list_append(symref, sym);
86 item->util = target;
87 return;
88reject:
89 free(sym);
90 return;
91}
92
93static void annotate_refs_with_symref_info(struct ref *ref)
94{
95 struct string_list symref = STRING_LIST_INIT_DUP;
96 const char *feature_list = server_capabilities;
97
98 while (feature_list) {
99 int len;
100 const char *val;
101
102 val = parse_feature_value(feature_list, "symref", &len);
103 if (!val)
104 break;
105 parse_one_symref_info(&symref, val, len);
106 feature_list = val + 1;
107 }
108 sort_string_list(&symref);
109
110 for (; ref; ref = ref->next) {
111 struct string_list_item *item;
112 item = string_list_lookup(&symref, ref->name);
113 if (!item)
114 continue;
115 ref->symref = xstrdup((char *)item->util);
116 }
117 string_list_clear(&symref, 0);
118}
119
120/*
121 * Read all the refs from the other end
122 */
123struct ref **get_remote_heads(int in, char *src_buf, size_t src_len,
124 struct ref **list, unsigned int flags,
125 struct extra_have_objects *extra_have)
126{
127 struct ref **orig_list = list;
128 int got_at_least_one_head = 0;
129
130 *list = NULL;
131 for (;;) {
132 struct ref *ref;
133 unsigned char old_sha1[20];
134 char *name;
135 int len, name_len;
136 char *buffer = packet_buffer;
137
138 len = packet_read(in, &src_buf, &src_len,
139 packet_buffer, sizeof(packet_buffer),
140 PACKET_READ_GENTLE_ON_EOF |
141 PACKET_READ_CHOMP_NEWLINE);
142 if (len < 0)
143 die_initial_contact(got_at_least_one_head);
144
145 if (!len)
146 break;
147
148 if (len > 4 && !prefixcmp(buffer, "ERR "))
149 die("remote error: %s", buffer + 4);
150
151 if (len < 42 || get_sha1_hex(buffer, old_sha1) || buffer[40] != ' ')
152 die("protocol error: expected sha/ref, got '%s'", buffer);
153 name = buffer + 41;
154
155 name_len = strlen(name);
156 if (len != name_len + 41) {
157 free(server_capabilities);
158 server_capabilities = xstrdup(name + name_len + 1);
159 }
160
161 if (extra_have &&
162 name_len == 5 && !memcmp(".have", name, 5)) {
163 add_extra_have(extra_have, old_sha1);
164 continue;
165 }
166
167 if (!check_ref(name, name_len, flags))
168 continue;
169 ref = alloc_ref(buffer + 41);
170 hashcpy(ref->old_sha1, old_sha1);
171 *list = ref;
172 list = &ref->next;
173 got_at_least_one_head = 1;
174 }
175
176 annotate_refs_with_symref_info(*orig_list);
177
178 return list;
179}
180
181static const char *parse_feature_value(const char *feature_list, const char *feature, int *lenp)
182{
183 int len;
184
185 if (!feature_list)
186 return NULL;
187
188 len = strlen(feature);
189 while (*feature_list) {
190 const char *found = strstr(feature_list, feature);
191 if (!found)
192 return NULL;
193 if (feature_list == found || isspace(found[-1])) {
194 const char *value = found + len;
195 /* feature with no value (e.g., "thin-pack") */
196 if (!*value || isspace(*value)) {
197 if (lenp)
198 *lenp = 0;
199 return value;
200 }
201 /* feature with a value (e.g., "agent=git/1.2.3") */
202 else if (*value == '=') {
203 value++;
204 if (lenp)
205 *lenp = strcspn(value, " \t\n");
206 return value;
207 }
208 /*
209 * otherwise we matched a substring of another feature;
210 * keep looking
211 */
212 }
213 feature_list = found + 1;
214 }
215 return NULL;
216}
217
218int parse_feature_request(const char *feature_list, const char *feature)
219{
220 return !!parse_feature_value(feature_list, feature, NULL);
221}
222
223const char *server_feature_value(const char *feature, int *len)
224{
225 return parse_feature_value(server_capabilities, feature, len);
226}
227
228int server_supports(const char *feature)
229{
230 return !!server_feature_value(feature, NULL);
231}
232
233enum protocol {
234 PROTO_LOCAL = 1,
235 PROTO_FILE,
236 PROTO_SSH,
237 PROTO_GIT
238};
239
240int url_is_local_not_ssh(const char *url)
241{
242 const char *colon = strchr(url, ':');
243 const char *slash = strchr(url, '/');
244 return !colon || (slash && slash < colon) ||
245 has_dos_drive_prefix(url);
246}
247
248static const char *prot_name(enum protocol protocol)
249{
250 switch (protocol) {
251 case PROTO_LOCAL:
252 case PROTO_FILE:
253 return "file";
254 case PROTO_SSH:
255 return "ssh";
256 case PROTO_GIT:
257 return "git";
258 default:
259 return "unkown protocol";
260 }
261}
262
263static enum protocol get_protocol(const char *name)
264{
265 if (!strcmp(name, "ssh"))
266 return PROTO_SSH;
267 if (!strcmp(name, "git"))
268 return PROTO_GIT;
269 if (!strcmp(name, "git+ssh"))
270 return PROTO_SSH;
271 if (!strcmp(name, "ssh+git"))
272 return PROTO_SSH;
273 if (!strcmp(name, "file"))
274 return PROTO_FILE;
275 die("I don't handle protocol '%s'", name);
276}
277
278#define STR_(s) # s
279#define STR(s) STR_(s)
280
281static void get_host_and_port(char **host, const char **port)
282{
283 char *colon, *end;
284
285 if (*host[0] == '[') {
286 end = strchr(*host + 1, ']');
287 if (end) {
288 *end = 0;
289 end++;
290 (*host)++;
291 } else
292 end = *host;
293 } else
294 end = *host;
295 colon = strchr(end, ':');
296
297 if (colon) {
298 *colon = 0;
299 *port = colon + 1;
300 }
301}
302
303static void enable_keepalive(int sockfd)
304{
305 int ka = 1;
306
307 if (setsockopt(sockfd, SOL_SOCKET, SO_KEEPALIVE, &ka, sizeof(ka)) < 0)
308 fprintf(stderr, "unable to set SO_KEEPALIVE on socket: %s\n",
309 strerror(errno));
310}
311
312#ifndef NO_IPV6
313
314static const char *ai_name(const struct addrinfo *ai)
315{
316 static char addr[NI_MAXHOST];
317 if (getnameinfo(ai->ai_addr, ai->ai_addrlen, addr, sizeof(addr), NULL, 0,
318 NI_NUMERICHOST) != 0)
319 strcpy(addr, "(unknown)");
320
321 return addr;
322}
323
324/*
325 * Returns a connected socket() fd, or else die()s.
326 */
327static int git_tcp_connect_sock(char *host, int flags)
328{
329 struct strbuf error_message = STRBUF_INIT;
330 int sockfd = -1;
331 const char *port = STR(DEFAULT_GIT_PORT);
332 struct addrinfo hints, *ai0, *ai;
333 int gai;
334 int cnt = 0;
335
336 get_host_and_port(&host, &port);
337 if (!*port)
338 port = "<none>";
339
340 memset(&hints, 0, sizeof(hints));
341 hints.ai_socktype = SOCK_STREAM;
342 hints.ai_protocol = IPPROTO_TCP;
343
344 if (flags & CONNECT_VERBOSE)
345 fprintf(stderr, "Looking up %s ... ", host);
346
347 gai = getaddrinfo(host, port, &hints, &ai);
348 if (gai)
349 die("Unable to look up %s (port %s) (%s)", host, port, gai_strerror(gai));
350
351 if (flags & CONNECT_VERBOSE)
352 fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
353
354 for (ai0 = ai; ai; ai = ai->ai_next, cnt++) {
355 sockfd = socket(ai->ai_family,
356 ai->ai_socktype, ai->ai_protocol);
357 if ((sockfd < 0) ||
358 (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0)) {
359 strbuf_addf(&error_message, "%s[%d: %s]: errno=%s\n",
360 host, cnt, ai_name(ai), strerror(errno));
361 if (0 <= sockfd)
362 close(sockfd);
363 sockfd = -1;
364 continue;
365 }
366 if (flags & CONNECT_VERBOSE)
367 fprintf(stderr, "%s ", ai_name(ai));
368 break;
369 }
370
371 freeaddrinfo(ai0);
372
373 if (sockfd < 0)
374 die("unable to connect to %s:\n%s", host, error_message.buf);
375
376 enable_keepalive(sockfd);
377
378 if (flags & CONNECT_VERBOSE)
379 fprintf(stderr, "done.\n");
380
381 strbuf_release(&error_message);
382
383 return sockfd;
384}
385
386#else /* NO_IPV6 */
387
388/*
389 * Returns a connected socket() fd, or else die()s.
390 */
391static int git_tcp_connect_sock(char *host, int flags)
392{
393 struct strbuf error_message = STRBUF_INIT;
394 int sockfd = -1;
395 const char *port = STR(DEFAULT_GIT_PORT);
396 char *ep;
397 struct hostent *he;
398 struct sockaddr_in sa;
399 char **ap;
400 unsigned int nport;
401 int cnt;
402
403 get_host_and_port(&host, &port);
404
405 if (flags & CONNECT_VERBOSE)
406 fprintf(stderr, "Looking up %s ... ", host);
407
408 he = gethostbyname(host);
409 if (!he)
410 die("Unable to look up %s (%s)", host, hstrerror(h_errno));
411 nport = strtoul(port, &ep, 10);
412 if ( ep == port || *ep ) {
413 /* Not numeric */
414 struct servent *se = getservbyname(port,"tcp");
415 if ( !se )
416 die("Unknown port %s", port);
417 nport = se->s_port;
418 }
419
420 if (flags & CONNECT_VERBOSE)
421 fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
422
423 for (cnt = 0, ap = he->h_addr_list; *ap; ap++, cnt++) {
424 memset(&sa, 0, sizeof sa);
425 sa.sin_family = he->h_addrtype;
426 sa.sin_port = htons(nport);
427 memcpy(&sa.sin_addr, *ap, he->h_length);
428
429 sockfd = socket(he->h_addrtype, SOCK_STREAM, 0);
430 if ((sockfd < 0) ||
431 connect(sockfd, (struct sockaddr *)&sa, sizeof sa) < 0) {
432 strbuf_addf(&error_message, "%s[%d: %s]: errno=%s\n",
433 host,
434 cnt,
435 inet_ntoa(*(struct in_addr *)&sa.sin_addr),
436 strerror(errno));
437 if (0 <= sockfd)
438 close(sockfd);
439 sockfd = -1;
440 continue;
441 }
442 if (flags & CONNECT_VERBOSE)
443 fprintf(stderr, "%s ",
444 inet_ntoa(*(struct in_addr *)&sa.sin_addr));
445 break;
446 }
447
448 if (sockfd < 0)
449 die("unable to connect to %s:\n%s", host, error_message.buf);
450
451 enable_keepalive(sockfd);
452
453 if (flags & CONNECT_VERBOSE)
454 fprintf(stderr, "done.\n");
455
456 return sockfd;
457}
458
459#endif /* NO_IPV6 */
460
461
462static void git_tcp_connect(int fd[2], char *host, int flags)
463{
464 int sockfd = git_tcp_connect_sock(host, flags);
465
466 fd[0] = sockfd;
467 fd[1] = dup(sockfd);
468}
469
470
471static char *git_proxy_command;
472
473static int git_proxy_command_options(const char *var, const char *value,
474 void *cb)
475{
476 if (!strcmp(var, "core.gitproxy")) {
477 const char *for_pos;
478 int matchlen = -1;
479 int hostlen;
480 const char *rhost_name = cb;
481 int rhost_len = strlen(rhost_name);
482
483 if (git_proxy_command)
484 return 0;
485 if (!value)
486 return config_error_nonbool(var);
487 /* [core]
488 * ;# matches www.kernel.org as well
489 * gitproxy = netcatter-1 for kernel.org
490 * gitproxy = netcatter-2 for sample.xz
491 * gitproxy = netcatter-default
492 */
493 for_pos = strstr(value, " for ");
494 if (!for_pos)
495 /* matches everybody */
496 matchlen = strlen(value);
497 else {
498 hostlen = strlen(for_pos + 5);
499 if (rhost_len < hostlen)
500 matchlen = -1;
501 else if (!strncmp(for_pos + 5,
502 rhost_name + rhost_len - hostlen,
503 hostlen) &&
504 ((rhost_len == hostlen) ||
505 rhost_name[rhost_len - hostlen -1] == '.'))
506 matchlen = for_pos - value;
507 else
508 matchlen = -1;
509 }
510 if (0 <= matchlen) {
511 /* core.gitproxy = none for kernel.org */
512 if (matchlen == 4 &&
513 !memcmp(value, "none", 4))
514 matchlen = 0;
515 git_proxy_command = xmemdupz(value, matchlen);
516 }
517 return 0;
518 }
519
520 return git_default_config(var, value, cb);
521}
522
523static int git_use_proxy(const char *host)
524{
525 git_proxy_command = getenv("GIT_PROXY_COMMAND");
526 git_config(git_proxy_command_options, (void*)host);
527 return (git_proxy_command && *git_proxy_command);
528}
529
530static struct child_process *git_proxy_connect(int fd[2], char *host)
531{
532 const char *port = STR(DEFAULT_GIT_PORT);
533 const char **argv;
534 struct child_process *proxy;
535
536 get_host_and_port(&host, &port);
537
538 argv = xmalloc(sizeof(*argv) * 4);
539 argv[0] = git_proxy_command;
540 argv[1] = host;
541 argv[2] = port;
542 argv[3] = NULL;
543 proxy = xcalloc(1, sizeof(*proxy));
544 proxy->argv = argv;
545 proxy->in = -1;
546 proxy->out = -1;
547 if (start_command(proxy))
548 die("cannot start proxy %s", argv[0]);
549 fd[0] = proxy->out; /* read from proxy stdout */
550 fd[1] = proxy->in; /* write to proxy stdin */
551 return proxy;
552}
553
554static const char *get_port_numeric(const char *p)
555{
556 char *end;
557 if (p) {
558 long port = strtol(p + 1, &end, 10);
559 if (end != p + 1 && *end == '\0' && 0 <= port && port < 65536) {
560 return p;
561 }
562 }
563
564 return NULL;
565}
566
567/*
568 * Extract protocol and relevant parts from the specified connection URL.
569 * The caller must free() the returned strings.
570 */
571static enum protocol parse_connect_url(const char *url_orig, char **ret_host,
572 char **ret_path)
573{
574 char *url;
575 char *host, *path;
576 char *end;
577 int separator = '/';
578 enum protocol protocol = PROTO_LOCAL;
579
580 if (is_url(url_orig))
581 url = url_decode(url_orig);
582 else
583 url = xstrdup(url_orig);
584
585 host = strstr(url, "://");
586 if (host) {
587 *host = '\0';
588 protocol = get_protocol(url);
589 host += 3;
590 } else {
591 host = url;
592 if (!url_is_local_not_ssh(url)) {
593 protocol = PROTO_SSH;
594 separator = ':';
595 }
596 }
597
598 /*
599 * Don't do destructive transforms as protocol code does
600 * '[]' unwrapping in get_host_and_port()
601 */
602 if (host[0] == '[') {
603 end = strchr(host + 1, ']');
604 if (end) {
605 end++;
606 } else
607 end = host;
608 } else
609 end = host;
610
611 if (protocol == PROTO_LOCAL)
612 path = end;
613 else if (protocol == PROTO_FILE && has_dos_drive_prefix(end))
614 path = end; /* "file://$(pwd)" may be "file://C:/projects/repo" */
615 else
616 path = strchr(end, separator);
617
618 if (!path || !*path)
619 die("No path specified. See 'man git-pull' for valid url syntax");
620
621 /*
622 * null-terminate hostname and point path to ~ for URL's like this:
623 * ssh://host.xz/~user/repo
624 */
625
626 end = path; /* Need to \0 terminate host here */
627 if (separator == ':')
628 path++; /* path starts after ':' */
629 if (protocol == PROTO_GIT || protocol == PROTO_SSH) {
630 if (path[1] == '~')
631 path++;
632 }
633
634 path = xstrdup(path);
635 *end = '\0';
636
637 *ret_host = xstrdup(host);
638 *ret_path = path;
639 free(url);
640 return protocol;
641}
642
643static struct child_process no_fork;
644
645/*
646 * This returns a dummy child_process if the transport protocol does not
647 * need fork(2), or a struct child_process object if it does. Once done,
648 * finish the connection with finish_connect() with the value returned from
649 * this function (it is safe to call finish_connect() with NULL to support
650 * the former case).
651 *
652 * If it returns, the connect is successful; it just dies on errors (this
653 * will hopefully be changed in a libification effort, to return NULL when
654 * the connection failed).
655 */
656struct child_process *git_connect(int fd[2], const char *url,
657 const char *prog, int flags)
658{
659 char *hostandport, *path;
660 struct child_process *conn = &no_fork;
661 enum protocol protocol;
662 const char **arg;
663 struct strbuf cmd = STRBUF_INIT;
664
665 /* Without this we cannot rely on waitpid() to tell
666 * what happened to our children.
667 */
668 signal(SIGCHLD, SIG_DFL);
669
670 protocol = parse_connect_url(url, &hostandport, &path);
671 if (flags & CONNECT_DIAG_URL) {
672 printf("Diag: url=%s\n", url ? url : "NULL");
673 printf("Diag: protocol=%s\n", prot_name(protocol));
674 printf("Diag: hostandport=%s\n", hostandport ? hostandport : "NULL");
675 printf("Diag: path=%s\n", path ? path : "NULL");
676 conn = NULL;
677 } else if (protocol == PROTO_GIT) {
678 /* These underlying connection commands die() if they
679 * cannot connect.
680 */
681 char *target_host = xstrdup(hostandport);
682 if (git_use_proxy(hostandport))
683 conn = git_proxy_connect(fd, hostandport);
684 else
685 git_tcp_connect(fd, hostandport, flags);
686 /*
687 * Separate original protocol components prog and path
688 * from extended host header with a NUL byte.
689 *
690 * Note: Do not add any other headers here! Doing so
691 * will cause older git-daemon servers to crash.
692 */
693 packet_write(fd[1],
694 "%s %s%chost=%s%c",
695 prog, path, 0,
696 target_host, 0);
697 free(target_host);
698 } else {
699 conn = xcalloc(1, sizeof(*conn));
700
701 strbuf_addstr(&cmd, prog);
702 strbuf_addch(&cmd, ' ');
703 sq_quote_buf(&cmd, path);
704
705 conn->in = conn->out = -1;
706 conn->argv = arg = xcalloc(7, sizeof(*arg));
707 if (protocol == PROTO_SSH) {
708 const char *ssh = getenv("GIT_SSH");
709 int putty = ssh && strcasestr(ssh, "plink");
710 char *ssh_host = hostandport;
711 const char *port = NULL;
712 get_host_and_port(&ssh_host, &port);
713 port = get_port_numeric(port);
714
715 if (!ssh) ssh = "ssh";
716
717 *arg++ = ssh;
718 if (putty && !strcasestr(ssh, "tortoiseplink"))
719 *arg++ = "-batch";
720 if (port) {
721 /* P is for PuTTY, p is for OpenSSH */
722 *arg++ = putty ? "-P" : "-p";
723 *arg++ = port;
724 }
725 *arg++ = ssh_host;
726 } else {
727 /* remove repo-local variables from the environment */
728 conn->env = local_repo_env;
729 conn->use_shell = 1;
730 }
731 *arg++ = cmd.buf;
732 *arg = NULL;
733
734 if (start_command(conn))
735 die("unable to fork");
736
737 fd[0] = conn->out; /* read from child's stdout */
738 fd[1] = conn->in; /* write to child's stdin */
739 strbuf_release(&cmd);
740 }
741 free(hostandport);
742 free(path);
743 return conn;
744}
745
746int git_connection_is_socket(struct child_process *conn)
747{
748 return conn == &no_fork;
749}
750
751int finish_connect(struct child_process *conn)
752{
753 int code;
754 if (!conn || git_connection_is_socket(conn))
755 return 0;
756
757 code = finish_command(conn);
758 free(conn->argv);
759 free(conn);
760 return code;
761}