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#include "sha1-array.h"
12
13static char *server_capabilities;
14static const char *parse_feature_value(const char *, const char *, int *);
15
16static int check_ref(const char *name, int len, unsigned int flags)
17{
18 if (!flags)
19 return 1;
20
21 if (len < 5 || memcmp(name, "refs/", 5))
22 return 0;
23
24 /* Skip the "refs/" part */
25 name += 5;
26 len -= 5;
27
28 /* REF_NORMAL means that we don't want the magic fake tag refs */
29 if ((flags & REF_NORMAL) && check_refname_format(name, 0))
30 return 0;
31
32 /* REF_HEADS means that we want regular branch heads */
33 if ((flags & REF_HEADS) && !memcmp(name, "heads/", 6))
34 return 1;
35
36 /* REF_TAGS means that we want tags */
37 if ((flags & REF_TAGS) && !memcmp(name, "tags/", 5))
38 return 1;
39
40 /* All type bits clear means that we are ok with anything */
41 return !(flags & ~REF_NORMAL);
42}
43
44int check_ref_type(const struct ref *ref, int flags)
45{
46 return check_ref(ref->name, strlen(ref->name), flags);
47}
48
49static void die_initial_contact(int got_at_least_one_head)
50{
51 if (got_at_least_one_head)
52 die("The remote end hung up upon initial contact");
53 else
54 die("Could not read from remote repository.\n\n"
55 "Please make sure you have the correct access rights\n"
56 "and the repository exists.");
57}
58
59static void parse_one_symref_info(struct string_list *symref, const char *val, int len)
60{
61 char *sym, *target;
62 struct string_list_item *item;
63
64 if (!len)
65 return; /* just "symref" */
66 /* e.g. "symref=HEAD:refs/heads/master" */
67 sym = xmemdupz(val, len);
68 target = strchr(sym, ':');
69 if (!target)
70 /* just "symref=something" */
71 goto reject;
72 *(target++) = '\0';
73 if (check_refname_format(sym, REFNAME_ALLOW_ONELEVEL) ||
74 check_refname_format(target, REFNAME_ALLOW_ONELEVEL))
75 /* "symref=bogus:pair */
76 goto reject;
77 item = string_list_append(symref, sym);
78 item->util = target;
79 return;
80reject:
81 free(sym);
82 return;
83}
84
85static void annotate_refs_with_symref_info(struct ref *ref)
86{
87 struct string_list symref = STRING_LIST_INIT_DUP;
88 const char *feature_list = server_capabilities;
89
90 while (feature_list) {
91 int len;
92 const char *val;
93
94 val = parse_feature_value(feature_list, "symref", &len);
95 if (!val)
96 break;
97 parse_one_symref_info(&symref, val, len);
98 feature_list = val + 1;
99 }
100 sort_string_list(&symref);
101
102 for (; ref; ref = ref->next) {
103 struct string_list_item *item;
104 item = string_list_lookup(&symref, ref->name);
105 if (!item)
106 continue;
107 ref->symref = xstrdup((char *)item->util);
108 }
109 string_list_clear(&symref, 0);
110}
111
112/*
113 * Read all the refs from the other end
114 */
115struct ref **get_remote_heads(int in, char *src_buf, size_t src_len,
116 struct ref **list, unsigned int flags,
117 struct sha1_array *extra_have,
118 struct sha1_array *shallow_points)
119{
120 struct ref **orig_list = list;
121 int got_at_least_one_head = 0;
122
123 *list = NULL;
124 for (;;) {
125 struct ref *ref;
126 unsigned char old_sha1[20];
127 char *name;
128 int len, name_len;
129 char *buffer = packet_buffer;
130
131 len = packet_read(in, &src_buf, &src_len,
132 packet_buffer, sizeof(packet_buffer),
133 PACKET_READ_GENTLE_ON_EOF |
134 PACKET_READ_CHOMP_NEWLINE);
135 if (len < 0)
136 die_initial_contact(got_at_least_one_head);
137
138 if (!len)
139 break;
140
141 if (len > 4 && starts_with(buffer, "ERR "))
142 die("remote error: %s", buffer + 4);
143
144 if (len == 48 && starts_with(buffer, "shallow ")) {
145 if (get_sha1_hex(buffer + 8, old_sha1))
146 die("protocol error: expected shallow sha-1, got '%s'", buffer + 8);
147 if (!shallow_points)
148 die("repository on the other end cannot be shallow");
149 sha1_array_append(shallow_points, old_sha1);
150 continue;
151 }
152
153 if (len < 42 || get_sha1_hex(buffer, old_sha1) || buffer[40] != ' ')
154 die("protocol error: expected sha/ref, got '%s'", buffer);
155 name = buffer + 41;
156
157 name_len = strlen(name);
158 if (len != name_len + 41) {
159 free(server_capabilities);
160 server_capabilities = xstrdup(name + name_len + 1);
161 }
162
163 if (extra_have &&
164 name_len == 5 && !memcmp(".have", name, 5)) {
165 sha1_array_append(extra_have, old_sha1);
166 continue;
167 }
168
169 if (!check_ref(name, name_len, flags))
170 continue;
171 ref = alloc_ref(buffer + 41);
172 hashcpy(ref->old_sha1, old_sha1);
173 *list = ref;
174 list = &ref->next;
175 got_at_least_one_head = 1;
176 }
177
178 annotate_refs_with_symref_info(*orig_list);
179
180 return list;
181}
182
183static const char *parse_feature_value(const char *feature_list, const char *feature, int *lenp)
184{
185 int len;
186
187 if (!feature_list)
188 return NULL;
189
190 len = strlen(feature);
191 while (*feature_list) {
192 const char *found = strstr(feature_list, feature);
193 if (!found)
194 return NULL;
195 if (feature_list == found || isspace(found[-1])) {
196 const char *value = found + len;
197 /* feature with no value (e.g., "thin-pack") */
198 if (!*value || isspace(*value)) {
199 if (lenp)
200 *lenp = 0;
201 return value;
202 }
203 /* feature with a value (e.g., "agent=git/1.2.3") */
204 else if (*value == '=') {
205 value++;
206 if (lenp)
207 *lenp = strcspn(value, " \t\n");
208 return value;
209 }
210 /*
211 * otherwise we matched a substring of another feature;
212 * keep looking
213 */
214 }
215 feature_list = found + 1;
216 }
217 return NULL;
218}
219
220int parse_feature_request(const char *feature_list, const char *feature)
221{
222 return !!parse_feature_value(feature_list, feature, NULL);
223}
224
225const char *server_feature_value(const char *feature, int *len)
226{
227 return parse_feature_value(server_capabilities, feature, len);
228}
229
230int server_supports(const char *feature)
231{
232 return !!server_feature_value(feature, NULL);
233}
234
235enum protocol {
236 PROTO_LOCAL = 1,
237 PROTO_FILE,
238 PROTO_SSH,
239 PROTO_GIT
240};
241
242int url_is_local_not_ssh(const char *url)
243{
244 const char *colon = strchr(url, ':');
245 const char *slash = strchr(url, '/');
246 return !colon || (slash && slash < colon) ||
247 has_dos_drive_prefix(url);
248}
249
250static const char *prot_name(enum protocol protocol)
251{
252 switch (protocol) {
253 case PROTO_LOCAL:
254 case PROTO_FILE:
255 return "file";
256 case PROTO_SSH:
257 return "ssh";
258 case PROTO_GIT:
259 return "git";
260 default:
261 return "unkown protocol";
262 }
263}
264
265static enum protocol get_protocol(const char *name)
266{
267 if (!strcmp(name, "ssh"))
268 return PROTO_SSH;
269 if (!strcmp(name, "git"))
270 return PROTO_GIT;
271 if (!strcmp(name, "git+ssh"))
272 return PROTO_SSH;
273 if (!strcmp(name, "ssh+git"))
274 return PROTO_SSH;
275 if (!strcmp(name, "file"))
276 return PROTO_FILE;
277 die("I don't handle protocol '%s'", name);
278}
279
280#define STR_(s) # s
281#define STR(s) STR_(s)
282
283static void get_host_and_port(char **host, const char **port)
284{
285 char *colon, *end;
286
287 if (*host[0] == '[') {
288 end = strchr(*host + 1, ']');
289 if (end) {
290 *end = 0;
291 end++;
292 (*host)++;
293 } else
294 end = *host;
295 } else
296 end = *host;
297 colon = strchr(end, ':');
298
299 if (colon) {
300 *colon = 0;
301 *port = colon + 1;
302 }
303}
304
305static void enable_keepalive(int sockfd)
306{
307 int ka = 1;
308
309 if (setsockopt(sockfd, SOL_SOCKET, SO_KEEPALIVE, &ka, sizeof(ka)) < 0)
310 fprintf(stderr, "unable to set SO_KEEPALIVE on socket: %s\n",
311 strerror(errno));
312}
313
314#ifndef NO_IPV6
315
316static const char *ai_name(const struct addrinfo *ai)
317{
318 static char addr[NI_MAXHOST];
319 if (getnameinfo(ai->ai_addr, ai->ai_addrlen, addr, sizeof(addr), NULL, 0,
320 NI_NUMERICHOST) != 0)
321 strcpy(addr, "(unknown)");
322
323 return addr;
324}
325
326/*
327 * Returns a connected socket() fd, or else die()s.
328 */
329static int git_tcp_connect_sock(char *host, int flags)
330{
331 struct strbuf error_message = STRBUF_INIT;
332 int sockfd = -1;
333 const char *port = STR(DEFAULT_GIT_PORT);
334 struct addrinfo hints, *ai0, *ai;
335 int gai;
336 int cnt = 0;
337
338 get_host_and_port(&host, &port);
339 if (!*port)
340 port = "<none>";
341
342 memset(&hints, 0, sizeof(hints));
343 hints.ai_socktype = SOCK_STREAM;
344 hints.ai_protocol = IPPROTO_TCP;
345
346 if (flags & CONNECT_VERBOSE)
347 fprintf(stderr, "Looking up %s ... ", host);
348
349 gai = getaddrinfo(host, port, &hints, &ai);
350 if (gai)
351 die("Unable to look up %s (port %s) (%s)", host, port, gai_strerror(gai));
352
353 if (flags & CONNECT_VERBOSE)
354 fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
355
356 for (ai0 = ai; ai; ai = ai->ai_next, cnt++) {
357 sockfd = socket(ai->ai_family,
358 ai->ai_socktype, ai->ai_protocol);
359 if ((sockfd < 0) ||
360 (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0)) {
361 strbuf_addf(&error_message, "%s[%d: %s]: errno=%s\n",
362 host, cnt, ai_name(ai), strerror(errno));
363 if (0 <= sockfd)
364 close(sockfd);
365 sockfd = -1;
366 continue;
367 }
368 if (flags & CONNECT_VERBOSE)
369 fprintf(stderr, "%s ", ai_name(ai));
370 break;
371 }
372
373 freeaddrinfo(ai0);
374
375 if (sockfd < 0)
376 die("unable to connect to %s:\n%s", host, error_message.buf);
377
378 enable_keepalive(sockfd);
379
380 if (flags & CONNECT_VERBOSE)
381 fprintf(stderr, "done.\n");
382
383 strbuf_release(&error_message);
384
385 return sockfd;
386}
387
388#else /* NO_IPV6 */
389
390/*
391 * Returns a connected socket() fd, or else die()s.
392 */
393static int git_tcp_connect_sock(char *host, int flags)
394{
395 struct strbuf error_message = STRBUF_INIT;
396 int sockfd = -1;
397 const char *port = STR(DEFAULT_GIT_PORT);
398 char *ep;
399 struct hostent *he;
400 struct sockaddr_in sa;
401 char **ap;
402 unsigned int nport;
403 int cnt;
404
405 get_host_and_port(&host, &port);
406
407 if (flags & CONNECT_VERBOSE)
408 fprintf(stderr, "Looking up %s ... ", host);
409
410 he = gethostbyname(host);
411 if (!he)
412 die("Unable to look up %s (%s)", host, hstrerror(h_errno));
413 nport = strtoul(port, &ep, 10);
414 if ( ep == port || *ep ) {
415 /* Not numeric */
416 struct servent *se = getservbyname(port,"tcp");
417 if ( !se )
418 die("Unknown port %s", port);
419 nport = se->s_port;
420 }
421
422 if (flags & CONNECT_VERBOSE)
423 fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
424
425 for (cnt = 0, ap = he->h_addr_list; *ap; ap++, cnt++) {
426 memset(&sa, 0, sizeof sa);
427 sa.sin_family = he->h_addrtype;
428 sa.sin_port = htons(nport);
429 memcpy(&sa.sin_addr, *ap, he->h_length);
430
431 sockfd = socket(he->h_addrtype, SOCK_STREAM, 0);
432 if ((sockfd < 0) ||
433 connect(sockfd, (struct sockaddr *)&sa, sizeof sa) < 0) {
434 strbuf_addf(&error_message, "%s[%d: %s]: errno=%s\n",
435 host,
436 cnt,
437 inet_ntoa(*(struct in_addr *)&sa.sin_addr),
438 strerror(errno));
439 if (0 <= sockfd)
440 close(sockfd);
441 sockfd = -1;
442 continue;
443 }
444 if (flags & CONNECT_VERBOSE)
445 fprintf(stderr, "%s ",
446 inet_ntoa(*(struct in_addr *)&sa.sin_addr));
447 break;
448 }
449
450 if (sockfd < 0)
451 die("unable to connect to %s:\n%s", host, error_message.buf);
452
453 enable_keepalive(sockfd);
454
455 if (flags & CONNECT_VERBOSE)
456 fprintf(stderr, "done.\n");
457
458 return sockfd;
459}
460
461#endif /* NO_IPV6 */
462
463
464static void git_tcp_connect(int fd[2], char *host, int flags)
465{
466 int sockfd = git_tcp_connect_sock(host, flags);
467
468 fd[0] = sockfd;
469 fd[1] = dup(sockfd);
470}
471
472
473static char *git_proxy_command;
474
475static int git_proxy_command_options(const char *var, const char *value,
476 void *cb)
477{
478 if (!strcmp(var, "core.gitproxy")) {
479 const char *for_pos;
480 int matchlen = -1;
481 int hostlen;
482 const char *rhost_name = cb;
483 int rhost_len = strlen(rhost_name);
484
485 if (git_proxy_command)
486 return 0;
487 if (!value)
488 return config_error_nonbool(var);
489 /* [core]
490 * ;# matches www.kernel.org as well
491 * gitproxy = netcatter-1 for kernel.org
492 * gitproxy = netcatter-2 for sample.xz
493 * gitproxy = netcatter-default
494 */
495 for_pos = strstr(value, " for ");
496 if (!for_pos)
497 /* matches everybody */
498 matchlen = strlen(value);
499 else {
500 hostlen = strlen(for_pos + 5);
501 if (rhost_len < hostlen)
502 matchlen = -1;
503 else if (!strncmp(for_pos + 5,
504 rhost_name + rhost_len - hostlen,
505 hostlen) &&
506 ((rhost_len == hostlen) ||
507 rhost_name[rhost_len - hostlen -1] == '.'))
508 matchlen = for_pos - value;
509 else
510 matchlen = -1;
511 }
512 if (0 <= matchlen) {
513 /* core.gitproxy = none for kernel.org */
514 if (matchlen == 4 &&
515 !memcmp(value, "none", 4))
516 matchlen = 0;
517 git_proxy_command = xmemdupz(value, matchlen);
518 }
519 return 0;
520 }
521
522 return git_default_config(var, value, cb);
523}
524
525static int git_use_proxy(const char *host)
526{
527 git_proxy_command = getenv("GIT_PROXY_COMMAND");
528 git_config(git_proxy_command_options, (void*)host);
529 return (git_proxy_command && *git_proxy_command);
530}
531
532static struct child_process *git_proxy_connect(int fd[2], char *host)
533{
534 const char *port = STR(DEFAULT_GIT_PORT);
535 const char **argv;
536 struct child_process *proxy;
537
538 get_host_and_port(&host, &port);
539
540 argv = xmalloc(sizeof(*argv) * 4);
541 argv[0] = git_proxy_command;
542 argv[1] = host;
543 argv[2] = port;
544 argv[3] = NULL;
545 proxy = xcalloc(1, sizeof(*proxy));
546 proxy->argv = argv;
547 proxy->in = -1;
548 proxy->out = -1;
549 if (start_command(proxy))
550 die("cannot start proxy %s", argv[0]);
551 fd[0] = proxy->out; /* read from proxy stdout */
552 fd[1] = proxy->in; /* write to proxy stdin */
553 return proxy;
554}
555
556static const char *get_port_numeric(const char *p)
557{
558 char *end;
559 if (p) {
560 long port = strtol(p + 1, &end, 10);
561 if (end != p + 1 && *end == '\0' && 0 <= port && port < 65536) {
562 return p;
563 }
564 }
565
566 return NULL;
567}
568
569/*
570 * Extract protocol and relevant parts from the specified connection URL.
571 * The caller must free() the returned strings.
572 */
573static enum protocol parse_connect_url(const char *url_orig, char **ret_host,
574 char **ret_path)
575{
576 char *url;
577 char *host, *path;
578 char *end;
579 int separator = '/';
580 enum protocol protocol = PROTO_LOCAL;
581
582 if (is_url(url_orig))
583 url = url_decode(url_orig);
584 else
585 url = xstrdup(url_orig);
586
587 host = strstr(url, "://");
588 if (host) {
589 *host = '\0';
590 protocol = get_protocol(url);
591 host += 3;
592 } else {
593 host = url;
594 if (!url_is_local_not_ssh(url)) {
595 protocol = PROTO_SSH;
596 separator = ':';
597 }
598 }
599
600 /*
601 * Don't do destructive transforms as protocol code does
602 * '[]' unwrapping in get_host_and_port()
603 */
604 if (host[0] == '[') {
605 end = strchr(host + 1, ']');
606 if (end) {
607 end++;
608 } else
609 end = host;
610 } else
611 end = host;
612
613 if (protocol == PROTO_LOCAL)
614 path = end;
615 else if (protocol == PROTO_FILE && has_dos_drive_prefix(end))
616 path = end; /* "file://$(pwd)" may be "file://C:/projects/repo" */
617 else
618 path = strchr(end, separator);
619
620 if (!path || !*path)
621 die("No path specified. See 'man git-pull' for valid url syntax");
622
623 /*
624 * null-terminate hostname and point path to ~ for URL's like this:
625 * ssh://host.xz/~user/repo
626 */
627
628 end = path; /* Need to \0 terminate host here */
629 if (separator == ':')
630 path++; /* path starts after ':' */
631 if (protocol == PROTO_GIT || protocol == PROTO_SSH) {
632 if (path[1] == '~')
633 path++;
634 }
635
636 path = xstrdup(path);
637 *end = '\0';
638
639 *ret_host = xstrdup(host);
640 *ret_path = path;
641 free(url);
642 return protocol;
643}
644
645static struct child_process no_fork;
646
647/*
648 * This returns a dummy child_process if the transport protocol does not
649 * need fork(2), or a struct child_process object if it does. Once done,
650 * finish the connection with finish_connect() with the value returned from
651 * this function (it is safe to call finish_connect() with NULL to support
652 * the former case).
653 *
654 * If it returns, the connect is successful; it just dies on errors (this
655 * will hopefully be changed in a libification effort, to return NULL when
656 * the connection failed).
657 */
658struct child_process *git_connect(int fd[2], const char *url,
659 const char *prog, int flags)
660{
661 char *hostandport, *path;
662 struct child_process *conn = &no_fork;
663 enum protocol protocol;
664 const char **arg;
665 struct strbuf cmd = STRBUF_INIT;
666
667 /* Without this we cannot rely on waitpid() to tell
668 * what happened to our children.
669 */
670 signal(SIGCHLD, SIG_DFL);
671
672 protocol = parse_connect_url(url, &hostandport, &path);
673 if (flags & CONNECT_DIAG_URL) {
674 printf("Diag: url=%s\n", url ? url : "NULL");
675 printf("Diag: protocol=%s\n", prot_name(protocol));
676 printf("Diag: hostandport=%s\n", hostandport ? hostandport : "NULL");
677 printf("Diag: path=%s\n", path ? path : "NULL");
678 conn = NULL;
679 } else if (protocol == PROTO_GIT) {
680 /* These underlying connection commands die() if they
681 * cannot connect.
682 */
683 char *target_host = xstrdup(hostandport);
684 if (git_use_proxy(hostandport))
685 conn = git_proxy_connect(fd, hostandport);
686 else
687 git_tcp_connect(fd, hostandport, flags);
688 /*
689 * Separate original protocol components prog and path
690 * from extended host header with a NUL byte.
691 *
692 * Note: Do not add any other headers here! Doing so
693 * will cause older git-daemon servers to crash.
694 */
695 packet_write(fd[1],
696 "%s %s%chost=%s%c",
697 prog, path, 0,
698 target_host, 0);
699 free(target_host);
700 } else {
701 conn = xcalloc(1, sizeof(*conn));
702
703 strbuf_addstr(&cmd, prog);
704 strbuf_addch(&cmd, ' ');
705 sq_quote_buf(&cmd, path);
706
707 conn->in = conn->out = -1;
708 conn->argv = arg = xcalloc(7, sizeof(*arg));
709 if (protocol == PROTO_SSH) {
710 const char *ssh = getenv("GIT_SSH");
711 int putty = ssh && strcasestr(ssh, "plink");
712 char *ssh_host = hostandport;
713 const char *port = NULL;
714 get_host_and_port(&ssh_host, &port);
715 port = get_port_numeric(port);
716
717 if (!ssh) ssh = "ssh";
718
719 *arg++ = ssh;
720 if (putty && !strcasestr(ssh, "tortoiseplink"))
721 *arg++ = "-batch";
722 if (port) {
723 /* P is for PuTTY, p is for OpenSSH */
724 *arg++ = putty ? "-P" : "-p";
725 *arg++ = port;
726 }
727 *arg++ = ssh_host;
728 } else {
729 /* remove repo-local variables from the environment */
730 conn->env = local_repo_env;
731 conn->use_shell = 1;
732 }
733 *arg++ = cmd.buf;
734 *arg = NULL;
735
736 if (start_command(conn))
737 die("unable to fork");
738
739 fd[0] = conn->out; /* read from child's stdout */
740 fd[1] = conn->in; /* write to child's stdin */
741 strbuf_release(&cmd);
742 }
743 free(hostandport);
744 free(path);
745 return conn;
746}
747
748int git_connection_is_socket(struct child_process *conn)
749{
750 return conn == &no_fork;
751}
752
753int finish_connect(struct child_process *conn)
754{
755 int code;
756 if (!conn || git_connection_is_socket(conn))
757 return 0;
758
759 code = finish_command(conn);
760 free(conn->argv);
761 free(conn);
762 return code;
763}