Merge branch 'jk/path-name-safety-2.4' into jk/path-name-safety-2.5
[git/debian.git] / connect.c
blob27a706f76621621a25b7e58188e5d1da9b9a2ccd
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 #include "transport.h"
14 static char *server_capabilities;
15 static const char *parse_feature_value(const char *, const char *, int *);
17 static int check_ref(const char *name, unsigned int flags)
19 if (!flags)
20 return 1;
22 if (!skip_prefix(name, "refs/", &name))
23 return 0;
25 /* REF_NORMAL means that we don't want the magic fake tag refs */
26 if ((flags & REF_NORMAL) && check_refname_format(name, 0))
27 return 0;
29 /* REF_HEADS means that we want regular branch heads */
30 if ((flags & REF_HEADS) && starts_with(name, "heads/"))
31 return 1;
33 /* REF_TAGS means that we want tags */
34 if ((flags & REF_TAGS) && starts_with(name, "tags/"))
35 return 1;
37 /* All type bits clear means that we are ok with anything */
38 return !(flags & ~REF_NORMAL);
41 int check_ref_type(const struct ref *ref, int flags)
43 return check_ref(ref->name, flags);
46 static void die_initial_contact(int got_at_least_one_head)
48 if (got_at_least_one_head)
49 die("The remote end hung up upon initial contact");
50 else
51 die("Could not read from remote repository.\n\n"
52 "Please make sure you have the correct access rights\n"
53 "and the repository exists.");
56 static void parse_one_symref_info(struct string_list *symref, const char *val, int len)
58 char *sym, *target;
59 struct string_list_item *item;
61 if (!len)
62 return; /* just "symref" */
63 /* e.g. "symref=HEAD:refs/heads/master" */
64 sym = xmemdupz(val, len);
65 target = strchr(sym, ':');
66 if (!target)
67 /* just "symref=something" */
68 goto reject;
69 *(target++) = '\0';
70 if (check_refname_format(sym, REFNAME_ALLOW_ONELEVEL) ||
71 check_refname_format(target, REFNAME_ALLOW_ONELEVEL))
72 /* "symref=bogus:pair */
73 goto reject;
74 item = string_list_append(symref, sym);
75 item->util = target;
76 return;
77 reject:
78 free(sym);
79 return;
82 static void annotate_refs_with_symref_info(struct ref *ref)
84 struct string_list symref = STRING_LIST_INIT_DUP;
85 const char *feature_list = server_capabilities;
87 while (feature_list) {
88 int len;
89 const char *val;
91 val = parse_feature_value(feature_list, "symref", &len);
92 if (!val)
93 break;
94 parse_one_symref_info(&symref, val, len);
95 feature_list = val + 1;
97 string_list_sort(&symref);
99 for (; ref; ref = ref->next) {
100 struct string_list_item *item;
101 item = string_list_lookup(&symref, ref->name);
102 if (!item)
103 continue;
104 ref->symref = xstrdup((char *)item->util);
106 string_list_clear(&symref, 0);
110 * Read all the refs from the other end
112 struct ref **get_remote_heads(int in, char *src_buf, size_t src_len,
113 struct ref **list, unsigned int flags,
114 struct sha1_array *extra_have,
115 struct sha1_array *shallow_points)
117 struct ref **orig_list = list;
118 int got_at_least_one_head = 0;
120 *list = NULL;
121 for (;;) {
122 struct ref *ref;
123 unsigned char old_sha1[20];
124 char *name;
125 int len, name_len;
126 char *buffer = packet_buffer;
127 const char *arg;
129 len = packet_read(in, &src_buf, &src_len,
130 packet_buffer, sizeof(packet_buffer),
131 PACKET_READ_GENTLE_ON_EOF |
132 PACKET_READ_CHOMP_NEWLINE);
133 if (len < 0)
134 die_initial_contact(got_at_least_one_head);
136 if (!len)
137 break;
139 if (len > 4 && skip_prefix(buffer, "ERR ", &arg))
140 die("remote error: %s", arg);
142 if (len == 48 && skip_prefix(buffer, "shallow ", &arg)) {
143 if (get_sha1_hex(arg, old_sha1))
144 die("protocol error: expected shallow sha-1, got '%s'", arg);
145 if (!shallow_points)
146 die("repository on the other end cannot be shallow");
147 sha1_array_append(shallow_points, old_sha1);
148 continue;
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;
155 name_len = strlen(name);
156 if (len != name_len + 41) {
157 free(server_capabilities);
158 server_capabilities = xstrdup(name + name_len + 1);
161 if (extra_have && !strcmp(name, ".have")) {
162 sha1_array_append(extra_have, old_sha1);
163 continue;
166 if (!check_ref(name, flags))
167 continue;
168 ref = alloc_ref(buffer + 41);
169 hashcpy(ref->old_sha1, old_sha1);
170 *list = ref;
171 list = &ref->next;
172 got_at_least_one_head = 1;
175 annotate_refs_with_symref_info(*orig_list);
177 return list;
180 static const char *parse_feature_value(const char *feature_list, const char *feature, int *lenp)
182 int len;
184 if (!feature_list)
185 return NULL;
187 len = strlen(feature);
188 while (*feature_list) {
189 const char *found = strstr(feature_list, feature);
190 if (!found)
191 return NULL;
192 if (feature_list == found || isspace(found[-1])) {
193 const char *value = found + len;
194 /* feature with no value (e.g., "thin-pack") */
195 if (!*value || isspace(*value)) {
196 if (lenp)
197 *lenp = 0;
198 return value;
200 /* feature with a value (e.g., "agent=git/1.2.3") */
201 else if (*value == '=') {
202 value++;
203 if (lenp)
204 *lenp = strcspn(value, " \t\n");
205 return value;
208 * otherwise we matched a substring of another feature;
209 * keep looking
212 feature_list = found + 1;
214 return NULL;
217 int parse_feature_request(const char *feature_list, const char *feature)
219 return !!parse_feature_value(feature_list, feature, NULL);
222 const char *server_feature_value(const char *feature, int *len)
224 return parse_feature_value(server_capabilities, feature, len);
227 int server_supports(const char *feature)
229 return !!server_feature_value(feature, NULL);
232 enum protocol {
233 PROTO_LOCAL = 1,
234 PROTO_FILE,
235 PROTO_SSH,
236 PROTO_GIT
239 int url_is_local_not_ssh(const char *url)
241 const char *colon = strchr(url, ':');
242 const char *slash = strchr(url, '/');
243 return !colon || (slash && slash < colon) ||
244 has_dos_drive_prefix(url);
247 static const char *prot_name(enum protocol protocol)
249 switch (protocol) {
250 case PROTO_LOCAL:
251 case PROTO_FILE:
252 return "file";
253 case PROTO_SSH:
254 return "ssh";
255 case PROTO_GIT:
256 return "git";
257 default:
258 return "unkown protocol";
262 static enum protocol get_protocol(const char *name)
264 if (!strcmp(name, "ssh"))
265 return PROTO_SSH;
266 if (!strcmp(name, "git"))
267 return PROTO_GIT;
268 if (!strcmp(name, "git+ssh"))
269 return PROTO_SSH;
270 if (!strcmp(name, "ssh+git"))
271 return PROTO_SSH;
272 if (!strcmp(name, "file"))
273 return PROTO_FILE;
274 die("I don't handle protocol '%s'", name);
277 static char *host_end(char **hoststart, int removebrackets)
279 char *host = *hoststart;
280 char *end;
281 char *start = strstr(host, "@[");
282 if (start)
283 start++; /* Jump over '@' */
284 else
285 start = host;
286 if (start[0] == '[') {
287 end = strchr(start + 1, ']');
288 if (end) {
289 if (removebrackets) {
290 *end = 0;
291 memmove(start, start + 1, end - start);
292 end++;
294 } else
295 end = host;
296 } else
297 end = host;
298 return end;
301 #define STR_(s) # s
302 #define STR(s) STR_(s)
304 static void get_host_and_port(char **host, const char **port)
306 char *colon, *end;
307 end = host_end(host, 1);
308 colon = strchr(end, ':');
309 if (colon) {
310 long portnr = strtol(colon + 1, &end, 10);
311 if (end != colon + 1 && *end == '\0' && 0 <= portnr && portnr < 65536) {
312 *colon = 0;
313 *port = colon + 1;
314 } else if (!colon[1]) {
315 *colon = 0;
320 static void enable_keepalive(int sockfd)
322 int ka = 1;
324 if (setsockopt(sockfd, SOL_SOCKET, SO_KEEPALIVE, &ka, sizeof(ka)) < 0)
325 fprintf(stderr, "unable to set SO_KEEPALIVE on socket: %s\n",
326 strerror(errno));
329 #ifndef NO_IPV6
331 static const char *ai_name(const struct addrinfo *ai)
333 static char addr[NI_MAXHOST];
334 if (getnameinfo(ai->ai_addr, ai->ai_addrlen, addr, sizeof(addr), NULL, 0,
335 NI_NUMERICHOST) != 0)
336 strcpy(addr, "(unknown)");
338 return addr;
342 * Returns a connected socket() fd, or else die()s.
344 static int git_tcp_connect_sock(char *host, int flags)
346 struct strbuf error_message = STRBUF_INIT;
347 int sockfd = -1;
348 const char *port = STR(DEFAULT_GIT_PORT);
349 struct addrinfo hints, *ai0, *ai;
350 int gai;
351 int cnt = 0;
353 get_host_and_port(&host, &port);
354 if (!*port)
355 port = "<none>";
357 memset(&hints, 0, sizeof(hints));
358 hints.ai_socktype = SOCK_STREAM;
359 hints.ai_protocol = IPPROTO_TCP;
361 if (flags & CONNECT_VERBOSE)
362 fprintf(stderr, "Looking up %s ... ", host);
364 gai = getaddrinfo(host, port, &hints, &ai);
365 if (gai)
366 die("Unable to look up %s (port %s) (%s)", host, port, gai_strerror(gai));
368 if (flags & CONNECT_VERBOSE)
369 fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
371 for (ai0 = ai; ai; ai = ai->ai_next, cnt++) {
372 sockfd = socket(ai->ai_family,
373 ai->ai_socktype, ai->ai_protocol);
374 if ((sockfd < 0) ||
375 (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0)) {
376 strbuf_addf(&error_message, "%s[%d: %s]: errno=%s\n",
377 host, cnt, ai_name(ai), strerror(errno));
378 if (0 <= sockfd)
379 close(sockfd);
380 sockfd = -1;
381 continue;
383 if (flags & CONNECT_VERBOSE)
384 fprintf(stderr, "%s ", ai_name(ai));
385 break;
388 freeaddrinfo(ai0);
390 if (sockfd < 0)
391 die("unable to connect to %s:\n%s", host, error_message.buf);
393 enable_keepalive(sockfd);
395 if (flags & CONNECT_VERBOSE)
396 fprintf(stderr, "done.\n");
398 strbuf_release(&error_message);
400 return sockfd;
403 #else /* NO_IPV6 */
406 * Returns a connected socket() fd, or else die()s.
408 static int git_tcp_connect_sock(char *host, int flags)
410 struct strbuf error_message = STRBUF_INIT;
411 int sockfd = -1;
412 const char *port = STR(DEFAULT_GIT_PORT);
413 char *ep;
414 struct hostent *he;
415 struct sockaddr_in sa;
416 char **ap;
417 unsigned int nport;
418 int cnt;
420 get_host_and_port(&host, &port);
422 if (flags & CONNECT_VERBOSE)
423 fprintf(stderr, "Looking up %s ... ", host);
425 he = gethostbyname(host);
426 if (!he)
427 die("Unable to look up %s (%s)", host, hstrerror(h_errno));
428 nport = strtoul(port, &ep, 10);
429 if ( ep == port || *ep ) {
430 /* Not numeric */
431 struct servent *se = getservbyname(port,"tcp");
432 if ( !se )
433 die("Unknown port %s", port);
434 nport = se->s_port;
437 if (flags & CONNECT_VERBOSE)
438 fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
440 for (cnt = 0, ap = he->h_addr_list; *ap; ap++, cnt++) {
441 memset(&sa, 0, sizeof sa);
442 sa.sin_family = he->h_addrtype;
443 sa.sin_port = htons(nport);
444 memcpy(&sa.sin_addr, *ap, he->h_length);
446 sockfd = socket(he->h_addrtype, SOCK_STREAM, 0);
447 if ((sockfd < 0) ||
448 connect(sockfd, (struct sockaddr *)&sa, sizeof sa) < 0) {
449 strbuf_addf(&error_message, "%s[%d: %s]: errno=%s\n",
450 host,
451 cnt,
452 inet_ntoa(*(struct in_addr *)&sa.sin_addr),
453 strerror(errno));
454 if (0 <= sockfd)
455 close(sockfd);
456 sockfd = -1;
457 continue;
459 if (flags & CONNECT_VERBOSE)
460 fprintf(stderr, "%s ",
461 inet_ntoa(*(struct in_addr *)&sa.sin_addr));
462 break;
465 if (sockfd < 0)
466 die("unable to connect to %s:\n%s", host, error_message.buf);
468 enable_keepalive(sockfd);
470 if (flags & CONNECT_VERBOSE)
471 fprintf(stderr, "done.\n");
473 return sockfd;
476 #endif /* NO_IPV6 */
479 static void git_tcp_connect(int fd[2], char *host, int flags)
481 int sockfd = git_tcp_connect_sock(host, flags);
483 fd[0] = sockfd;
484 fd[1] = dup(sockfd);
488 static char *git_proxy_command;
490 static int git_proxy_command_options(const char *var, const char *value,
491 void *cb)
493 if (!strcmp(var, "core.gitproxy")) {
494 const char *for_pos;
495 int matchlen = -1;
496 int hostlen;
497 const char *rhost_name = cb;
498 int rhost_len = strlen(rhost_name);
500 if (git_proxy_command)
501 return 0;
502 if (!value)
503 return config_error_nonbool(var);
504 /* [core]
505 * ;# matches www.kernel.org as well
506 * gitproxy = netcatter-1 for kernel.org
507 * gitproxy = netcatter-2 for sample.xz
508 * gitproxy = netcatter-default
510 for_pos = strstr(value, " for ");
511 if (!for_pos)
512 /* matches everybody */
513 matchlen = strlen(value);
514 else {
515 hostlen = strlen(for_pos + 5);
516 if (rhost_len < hostlen)
517 matchlen = -1;
518 else if (!strncmp(for_pos + 5,
519 rhost_name + rhost_len - hostlen,
520 hostlen) &&
521 ((rhost_len == hostlen) ||
522 rhost_name[rhost_len - hostlen -1] == '.'))
523 matchlen = for_pos - value;
524 else
525 matchlen = -1;
527 if (0 <= matchlen) {
528 /* core.gitproxy = none for kernel.org */
529 if (matchlen == 4 &&
530 !memcmp(value, "none", 4))
531 matchlen = 0;
532 git_proxy_command = xmemdupz(value, matchlen);
534 return 0;
537 return git_default_config(var, value, cb);
540 static int git_use_proxy(const char *host)
542 git_proxy_command = getenv("GIT_PROXY_COMMAND");
543 git_config(git_proxy_command_options, (void*)host);
544 return (git_proxy_command && *git_proxy_command);
547 static struct child_process *git_proxy_connect(int fd[2], char *host)
549 const char *port = STR(DEFAULT_GIT_PORT);
550 struct child_process *proxy;
552 get_host_and_port(&host, &port);
554 proxy = xmalloc(sizeof(*proxy));
555 child_process_init(proxy);
556 argv_array_push(&proxy->args, git_proxy_command);
557 argv_array_push(&proxy->args, host);
558 argv_array_push(&proxy->args, port);
559 proxy->in = -1;
560 proxy->out = -1;
561 if (start_command(proxy))
562 die("cannot start proxy %s", git_proxy_command);
563 fd[0] = proxy->out; /* read from proxy stdout */
564 fd[1] = proxy->in; /* write to proxy stdin */
565 return proxy;
568 static char *get_port(char *host)
570 char *end;
571 char *p = strchr(host, ':');
573 if (p) {
574 long port = strtol(p + 1, &end, 10);
575 if (end != p + 1 && *end == '\0' && 0 <= port && port < 65536) {
576 *p = '\0';
577 return p+1;
581 return NULL;
585 * Extract protocol and relevant parts from the specified connection URL.
586 * The caller must free() the returned strings.
588 static enum protocol parse_connect_url(const char *url_orig, char **ret_host,
589 char **ret_path)
591 char *url;
592 char *host, *path;
593 char *end;
594 int separator = '/';
595 enum protocol protocol = PROTO_LOCAL;
597 if (is_url(url_orig))
598 url = url_decode(url_orig);
599 else
600 url = xstrdup(url_orig);
602 host = strstr(url, "://");
603 if (host) {
604 *host = '\0';
605 protocol = get_protocol(url);
606 host += 3;
607 } else {
608 host = url;
609 if (!url_is_local_not_ssh(url)) {
610 protocol = PROTO_SSH;
611 separator = ':';
616 * Don't do destructive transforms as protocol code does
617 * '[]' unwrapping in get_host_and_port()
619 end = host_end(&host, 0);
621 if (protocol == PROTO_LOCAL)
622 path = end;
623 else if (protocol == PROTO_FILE && has_dos_drive_prefix(end))
624 path = end; /* "file://$(pwd)" may be "file://C:/projects/repo" */
625 else
626 path = strchr(end, separator);
628 if (!path || !*path)
629 die("No path specified. See 'man git-pull' for valid url syntax");
632 * null-terminate hostname and point path to ~ for URL's like this:
633 * ssh://host.xz/~user/repo
636 end = path; /* Need to \0 terminate host here */
637 if (separator == ':')
638 path++; /* path starts after ':' */
639 if (protocol == PROTO_GIT || protocol == PROTO_SSH) {
640 if (path[1] == '~')
641 path++;
644 path = xstrdup(path);
645 *end = '\0';
647 *ret_host = xstrdup(host);
648 *ret_path = path;
649 free(url);
650 return protocol;
653 static struct child_process no_fork = CHILD_PROCESS_INIT;
656 * This returns a dummy child_process if the transport protocol does not
657 * need fork(2), or a struct child_process object if it does. Once done,
658 * finish the connection with finish_connect() with the value returned from
659 * this function (it is safe to call finish_connect() with NULL to support
660 * the former case).
662 * If it returns, the connect is successful; it just dies on errors (this
663 * will hopefully be changed in a libification effort, to return NULL when
664 * the connection failed).
666 struct child_process *git_connect(int fd[2], const char *url,
667 const char *prog, int flags)
669 char *hostandport, *path;
670 struct child_process *conn = &no_fork;
671 enum protocol protocol;
672 struct strbuf cmd = STRBUF_INIT;
674 /* Without this we cannot rely on waitpid() to tell
675 * what happened to our children.
677 signal(SIGCHLD, SIG_DFL);
679 protocol = parse_connect_url(url, &hostandport, &path);
680 if ((flags & CONNECT_DIAG_URL) && (protocol != PROTO_SSH)) {
681 printf("Diag: url=%s\n", url ? url : "NULL");
682 printf("Diag: protocol=%s\n", prot_name(protocol));
683 printf("Diag: hostandport=%s\n", hostandport ? hostandport : "NULL");
684 printf("Diag: path=%s\n", path ? path : "NULL");
685 conn = NULL;
686 } else if (protocol == PROTO_GIT) {
688 * Set up virtual host information based on where we will
689 * connect, unless the user has overridden us in
690 * the environment.
692 char *target_host = getenv("GIT_OVERRIDE_VIRTUAL_HOST");
693 if (target_host)
694 target_host = xstrdup(target_host);
695 else
696 target_host = xstrdup(hostandport);
698 transport_check_allowed("git");
700 /* These underlying connection commands die() if they
701 * cannot connect.
703 if (git_use_proxy(hostandport))
704 conn = git_proxy_connect(fd, hostandport);
705 else
706 git_tcp_connect(fd, hostandport, flags);
708 * Separate original protocol components prog and path
709 * from extended host header with a NUL byte.
711 * Note: Do not add any other headers here! Doing so
712 * will cause older git-daemon servers to crash.
714 packet_write(fd[1],
715 "%s %s%chost=%s%c",
716 prog, path, 0,
717 target_host, 0);
718 free(target_host);
719 } else {
720 conn = xmalloc(sizeof(*conn));
721 child_process_init(conn);
723 strbuf_addstr(&cmd, prog);
724 strbuf_addch(&cmd, ' ');
725 sq_quote_buf(&cmd, path);
727 conn->in = conn->out = -1;
728 if (protocol == PROTO_SSH) {
729 const char *ssh;
730 int putty, tortoiseplink = 0;
731 char *ssh_host = hostandport;
732 const char *port = NULL;
733 transport_check_allowed("ssh");
734 get_host_and_port(&ssh_host, &port);
736 if (!port)
737 port = get_port(ssh_host);
739 if (flags & CONNECT_DIAG_URL) {
740 printf("Diag: url=%s\n", url ? url : "NULL");
741 printf("Diag: protocol=%s\n", prot_name(protocol));
742 printf("Diag: userandhost=%s\n", ssh_host ? ssh_host : "NULL");
743 printf("Diag: port=%s\n", port ? port : "NONE");
744 printf("Diag: path=%s\n", path ? path : "NULL");
746 free(hostandport);
747 free(path);
748 free(conn);
749 return NULL;
752 ssh = getenv("GIT_SSH_COMMAND");
753 if (ssh) {
754 conn->use_shell = 1;
755 putty = 0;
756 } else {
757 const char *base;
758 char *ssh_dup;
760 ssh = getenv("GIT_SSH");
761 if (!ssh)
762 ssh = "ssh";
764 ssh_dup = xstrdup(ssh);
765 base = basename(ssh_dup);
767 tortoiseplink = !strcasecmp(base, "tortoiseplink") ||
768 !strcasecmp(base, "tortoiseplink.exe");
769 putty = !strcasecmp(base, "plink") ||
770 !strcasecmp(base, "plink.exe") || tortoiseplink;
772 free(ssh_dup);
775 argv_array_push(&conn->args, ssh);
776 if (tortoiseplink)
777 argv_array_push(&conn->args, "-batch");
778 if (port) {
779 /* P is for PuTTY, p is for OpenSSH */
780 argv_array_push(&conn->args, putty ? "-P" : "-p");
781 argv_array_push(&conn->args, port);
783 argv_array_push(&conn->args, ssh_host);
784 } else {
785 /* remove repo-local variables from the environment */
786 conn->env = local_repo_env;
787 conn->use_shell = 1;
788 transport_check_allowed("file");
790 argv_array_push(&conn->args, cmd.buf);
792 if (start_command(conn))
793 die("unable to fork");
795 fd[0] = conn->out; /* read from child's stdout */
796 fd[1] = conn->in; /* write to child's stdin */
797 strbuf_release(&cmd);
799 free(hostandport);
800 free(path);
801 return conn;
804 int git_connection_is_socket(struct child_process *conn)
806 return conn == &no_fork;
809 int finish_connect(struct child_process *conn)
811 int code;
812 if (!conn || git_connection_is_socket(conn))
813 return 0;
815 code = finish_command(conn);
816 free(conn);
817 return code;