files-backend: avoid ref api targeting main ref store
[git/debian.git] / http-backend.c
blobeef0a361f4f9bcc7f8fb278268334cb40a32fcb3
1 #include "cache.h"
2 #include "refs.h"
3 #include "pkt-line.h"
4 #include "object.h"
5 #include "tag.h"
6 #include "exec_cmd.h"
7 #include "run-command.h"
8 #include "string-list.h"
9 #include "url.h"
10 #include "argv-array.h"
12 static const char content_type[] = "Content-Type";
13 static const char content_length[] = "Content-Length";
14 static const char last_modified[] = "Last-Modified";
15 static int getanyfile = 1;
16 static unsigned long max_request_buffer = 10 * 1024 * 1024;
18 static struct string_list *query_params;
20 struct rpc_service {
21 const char *name;
22 const char *config_name;
23 unsigned buffer_input : 1;
24 signed enabled : 2;
27 static struct rpc_service rpc_service[] = {
28 { "upload-pack", "uploadpack", 1, 1 },
29 { "receive-pack", "receivepack", 0, -1 },
32 static struct string_list *get_parameters(void)
34 if (!query_params) {
35 const char *query = getenv("QUERY_STRING");
37 query_params = xcalloc(1, sizeof(*query_params));
38 while (query && *query) {
39 char *name = url_decode_parameter_name(&query);
40 char *value = url_decode_parameter_value(&query);
41 struct string_list_item *i;
43 i = string_list_lookup(query_params, name);
44 if (!i)
45 i = string_list_insert(query_params, name);
46 else
47 free(i->util);
48 i->util = value;
51 return query_params;
54 static const char *get_parameter(const char *name)
56 struct string_list_item *i;
57 i = string_list_lookup(get_parameters(), name);
58 return i ? i->util : NULL;
61 __attribute__((format (printf, 2, 3)))
62 static void format_write(int fd, const char *fmt, ...)
64 static char buffer[1024];
66 va_list args;
67 unsigned n;
69 va_start(args, fmt);
70 n = vsnprintf(buffer, sizeof(buffer), fmt, args);
71 va_end(args);
72 if (n >= sizeof(buffer))
73 die("protocol error: impossibly long line");
75 write_or_die(fd, buffer, n);
78 static void http_status(struct strbuf *hdr, unsigned code, const char *msg)
80 strbuf_addf(hdr, "Status: %u %s\r\n", code, msg);
83 static void hdr_str(struct strbuf *hdr, const char *name, const char *value)
85 strbuf_addf(hdr, "%s: %s\r\n", name, value);
88 static void hdr_int(struct strbuf *hdr, const char *name, uintmax_t value)
90 strbuf_addf(hdr, "%s: %" PRIuMAX "\r\n", name, value);
93 static void hdr_date(struct strbuf *hdr, const char *name, unsigned long when)
95 const char *value = show_date(when, 0, DATE_MODE(RFC2822));
96 hdr_str(hdr, name, value);
99 static void hdr_nocache(struct strbuf *hdr)
101 hdr_str(hdr, "Expires", "Fri, 01 Jan 1980 00:00:00 GMT");
102 hdr_str(hdr, "Pragma", "no-cache");
103 hdr_str(hdr, "Cache-Control", "no-cache, max-age=0, must-revalidate");
106 static void hdr_cache_forever(struct strbuf *hdr)
108 unsigned long now = time(NULL);
109 hdr_date(hdr, "Date", now);
110 hdr_date(hdr, "Expires", now + 31536000);
111 hdr_str(hdr, "Cache-Control", "public, max-age=31536000");
114 static void end_headers(struct strbuf *hdr)
116 strbuf_add(hdr, "\r\n", 2);
117 write_or_die(1, hdr->buf, hdr->len);
118 strbuf_release(hdr);
121 __attribute__((format (printf, 2, 3)))
122 static NORETURN void not_found(struct strbuf *hdr, const char *err, ...)
124 va_list params;
126 http_status(hdr, 404, "Not Found");
127 hdr_nocache(hdr);
128 end_headers(hdr);
130 va_start(params, err);
131 if (err && *err)
132 vfprintf(stderr, err, params);
133 va_end(params);
134 exit(0);
137 __attribute__((format (printf, 2, 3)))
138 static NORETURN void forbidden(struct strbuf *hdr, const char *err, ...)
140 va_list params;
142 http_status(hdr, 403, "Forbidden");
143 hdr_nocache(hdr);
144 end_headers(hdr);
146 va_start(params, err);
147 if (err && *err)
148 vfprintf(stderr, err, params);
149 va_end(params);
150 exit(0);
153 static void select_getanyfile(struct strbuf *hdr)
155 if (!getanyfile)
156 forbidden(hdr, "Unsupported service: getanyfile");
159 static void send_strbuf(struct strbuf *hdr,
160 const char *type, struct strbuf *buf)
162 hdr_int(hdr, content_length, buf->len);
163 hdr_str(hdr, content_type, type);
164 end_headers(hdr);
165 write_or_die(1, buf->buf, buf->len);
168 static void send_local_file(struct strbuf *hdr, const char *the_type,
169 const char *name)
171 char *p = git_pathdup("%s", name);
172 size_t buf_alloc = 8192;
173 char *buf = xmalloc(buf_alloc);
174 int fd;
175 struct stat sb;
177 fd = open(p, O_RDONLY);
178 if (fd < 0)
179 not_found(hdr, "Cannot open '%s': %s", p, strerror(errno));
180 if (fstat(fd, &sb) < 0)
181 die_errno("Cannot stat '%s'", p);
183 hdr_int(hdr, content_length, sb.st_size);
184 hdr_str(hdr, content_type, the_type);
185 hdr_date(hdr, last_modified, sb.st_mtime);
186 end_headers(hdr);
188 for (;;) {
189 ssize_t n = xread(fd, buf, buf_alloc);
190 if (n < 0)
191 die_errno("Cannot read '%s'", p);
192 if (!n)
193 break;
194 write_or_die(1, buf, n);
196 close(fd);
197 free(buf);
198 free(p);
201 static void get_text_file(struct strbuf *hdr, char *name)
203 select_getanyfile(hdr);
204 hdr_nocache(hdr);
205 send_local_file(hdr, "text/plain", name);
208 static void get_loose_object(struct strbuf *hdr, char *name)
210 select_getanyfile(hdr);
211 hdr_cache_forever(hdr);
212 send_local_file(hdr, "application/x-git-loose-object", name);
215 static void get_pack_file(struct strbuf *hdr, char *name)
217 select_getanyfile(hdr);
218 hdr_cache_forever(hdr);
219 send_local_file(hdr, "application/x-git-packed-objects", name);
222 static void get_idx_file(struct strbuf *hdr, char *name)
224 select_getanyfile(hdr);
225 hdr_cache_forever(hdr);
226 send_local_file(hdr, "application/x-git-packed-objects-toc", name);
229 static void http_config(void)
231 int i, value = 0;
232 struct strbuf var = STRBUF_INIT;
234 git_config_get_bool("http.getanyfile", &getanyfile);
235 git_config_get_ulong("http.maxrequestbuffer", &max_request_buffer);
237 for (i = 0; i < ARRAY_SIZE(rpc_service); i++) {
238 struct rpc_service *svc = &rpc_service[i];
239 strbuf_addf(&var, "http.%s", svc->config_name);
240 if (!git_config_get_bool(var.buf, &value))
241 svc->enabled = value;
242 strbuf_reset(&var);
245 strbuf_release(&var);
248 static struct rpc_service *select_service(struct strbuf *hdr, const char *name)
250 const char *svc_name;
251 struct rpc_service *svc = NULL;
252 int i;
254 if (!skip_prefix(name, "git-", &svc_name))
255 forbidden(hdr, "Unsupported service: '%s'", name);
257 for (i = 0; i < ARRAY_SIZE(rpc_service); i++) {
258 struct rpc_service *s = &rpc_service[i];
259 if (!strcmp(s->name, svc_name)) {
260 svc = s;
261 break;
265 if (!svc)
266 forbidden(hdr, "Unsupported service: '%s'", name);
268 if (svc->enabled < 0) {
269 const char *user = getenv("REMOTE_USER");
270 svc->enabled = (user && *user) ? 1 : 0;
272 if (!svc->enabled)
273 forbidden(hdr, "Service not enabled: '%s'", svc->name);
274 return svc;
278 * This is basically strbuf_read(), except that if we
279 * hit max_request_buffer we die (we'd rather reject a
280 * maliciously large request than chew up infinite memory).
282 static ssize_t read_request(int fd, unsigned char **out)
284 size_t len = 0, alloc = 8192;
285 unsigned char *buf = xmalloc(alloc);
287 if (max_request_buffer < alloc)
288 max_request_buffer = alloc;
290 while (1) {
291 ssize_t cnt;
293 cnt = read_in_full(fd, buf + len, alloc - len);
294 if (cnt < 0) {
295 free(buf);
296 return -1;
299 /* partial read from read_in_full means we hit EOF */
300 len += cnt;
301 if (len < alloc) {
302 *out = buf;
303 return len;
306 /* otherwise, grow and try again (if we can) */
307 if (alloc == max_request_buffer)
308 die("request was larger than our maximum size (%lu);"
309 " try setting GIT_HTTP_MAX_REQUEST_BUFFER",
310 max_request_buffer);
312 alloc = alloc_nr(alloc);
313 if (alloc > max_request_buffer)
314 alloc = max_request_buffer;
315 REALLOC_ARRAY(buf, alloc);
319 static void inflate_request(const char *prog_name, int out, int buffer_input)
321 git_zstream stream;
322 unsigned char *full_request = NULL;
323 unsigned char in_buf[8192];
324 unsigned char out_buf[8192];
325 unsigned long cnt = 0;
327 memset(&stream, 0, sizeof(stream));
328 git_inflate_init_gzip_only(&stream);
330 while (1) {
331 ssize_t n;
333 if (buffer_input) {
334 if (full_request)
335 n = 0; /* nothing left to read */
336 else
337 n = read_request(0, &full_request);
338 stream.next_in = full_request;
339 } else {
340 n = xread(0, in_buf, sizeof(in_buf));
341 stream.next_in = in_buf;
344 if (n <= 0)
345 die("request ended in the middle of the gzip stream");
346 stream.avail_in = n;
348 while (0 < stream.avail_in) {
349 int ret;
351 stream.next_out = out_buf;
352 stream.avail_out = sizeof(out_buf);
354 ret = git_inflate(&stream, Z_NO_FLUSH);
355 if (ret != Z_OK && ret != Z_STREAM_END)
356 die("zlib error inflating request, result %d", ret);
358 n = stream.total_out - cnt;
359 if (write_in_full(out, out_buf, n) != n)
360 die("%s aborted reading request", prog_name);
361 cnt += n;
363 if (ret == Z_STREAM_END)
364 goto done;
368 done:
369 git_inflate_end(&stream);
370 close(out);
371 free(full_request);
374 static void copy_request(const char *prog_name, int out)
376 unsigned char *buf;
377 ssize_t n = read_request(0, &buf);
378 if (n < 0)
379 die_errno("error reading request body");
380 if (write_in_full(out, buf, n) != n)
381 die("%s aborted reading request", prog_name);
382 close(out);
383 free(buf);
386 static void run_service(const char **argv, int buffer_input)
388 const char *encoding = getenv("HTTP_CONTENT_ENCODING");
389 const char *user = getenv("REMOTE_USER");
390 const char *host = getenv("REMOTE_ADDR");
391 int gzipped_request = 0;
392 struct child_process cld = CHILD_PROCESS_INIT;
394 if (encoding && !strcmp(encoding, "gzip"))
395 gzipped_request = 1;
396 else if (encoding && !strcmp(encoding, "x-gzip"))
397 gzipped_request = 1;
399 if (!user || !*user)
400 user = "anonymous";
401 if (!host || !*host)
402 host = "(none)";
404 if (!getenv("GIT_COMMITTER_NAME"))
405 argv_array_pushf(&cld.env_array, "GIT_COMMITTER_NAME=%s", user);
406 if (!getenv("GIT_COMMITTER_EMAIL"))
407 argv_array_pushf(&cld.env_array,
408 "GIT_COMMITTER_EMAIL=%s@http.%s", user, host);
410 cld.argv = argv;
411 if (buffer_input || gzipped_request)
412 cld.in = -1;
413 cld.git_cmd = 1;
414 if (start_command(&cld))
415 exit(1);
417 close(1);
418 if (gzipped_request)
419 inflate_request(argv[0], cld.in, buffer_input);
420 else if (buffer_input)
421 copy_request(argv[0], cld.in);
422 else
423 close(0);
425 if (finish_command(&cld))
426 exit(1);
429 static int show_text_ref(const char *name, const struct object_id *oid,
430 int flag, void *cb_data)
432 const char *name_nons = strip_namespace(name);
433 struct strbuf *buf = cb_data;
434 struct object *o = parse_object(oid->hash);
435 if (!o)
436 return 0;
438 strbuf_addf(buf, "%s\t%s\n", oid_to_hex(oid), name_nons);
439 if (o->type == OBJ_TAG) {
440 o = deref_tag(o, name, 0);
441 if (!o)
442 return 0;
443 strbuf_addf(buf, "%s\t%s^{}\n", oid_to_hex(&o->oid),
444 name_nons);
446 return 0;
449 static void get_info_refs(struct strbuf *hdr, char *arg)
451 const char *service_name = get_parameter("service");
452 struct strbuf buf = STRBUF_INIT;
454 hdr_nocache(hdr);
456 if (service_name) {
457 const char *argv[] = {NULL /* service name */,
458 "--stateless-rpc", "--advertise-refs",
459 ".", NULL};
460 struct rpc_service *svc = select_service(hdr, service_name);
462 strbuf_addf(&buf, "application/x-git-%s-advertisement",
463 svc->name);
464 hdr_str(hdr, content_type, buf.buf);
465 end_headers(hdr);
467 packet_write_fmt(1, "# service=git-%s\n", svc->name);
468 packet_flush(1);
470 argv[0] = svc->name;
471 run_service(argv, 0);
473 } else {
474 select_getanyfile(hdr);
475 for_each_namespaced_ref(show_text_ref, &buf);
476 send_strbuf(hdr, "text/plain", &buf);
478 strbuf_release(&buf);
481 static int show_head_ref(const char *refname, const struct object_id *oid,
482 int flag, void *cb_data)
484 struct strbuf *buf = cb_data;
486 if (flag & REF_ISSYMREF) {
487 struct object_id unused;
488 const char *target = resolve_ref_unsafe(refname,
489 RESOLVE_REF_READING,
490 unused.hash, NULL);
492 if (target)
493 strbuf_addf(buf, "ref: %s\n", strip_namespace(target));
494 } else {
495 strbuf_addf(buf, "%s\n", oid_to_hex(oid));
498 return 0;
501 static void get_head(struct strbuf *hdr, char *arg)
503 struct strbuf buf = STRBUF_INIT;
505 select_getanyfile(hdr);
506 head_ref_namespaced(show_head_ref, &buf);
507 send_strbuf(hdr, "text/plain", &buf);
508 strbuf_release(&buf);
511 static void get_info_packs(struct strbuf *hdr, char *arg)
513 size_t objdirlen = strlen(get_object_directory());
514 struct strbuf buf = STRBUF_INIT;
515 struct packed_git *p;
516 size_t cnt = 0;
518 select_getanyfile(hdr);
519 prepare_packed_git();
520 for (p = packed_git; p; p = p->next) {
521 if (p->pack_local)
522 cnt++;
525 strbuf_grow(&buf, cnt * 53 + 2);
526 for (p = packed_git; p; p = p->next) {
527 if (p->pack_local)
528 strbuf_addf(&buf, "P %s\n", p->pack_name + objdirlen + 6);
530 strbuf_addch(&buf, '\n');
532 hdr_nocache(hdr);
533 send_strbuf(hdr, "text/plain; charset=utf-8", &buf);
534 strbuf_release(&buf);
537 static void check_content_type(struct strbuf *hdr, const char *accepted_type)
539 const char *actual_type = getenv("CONTENT_TYPE");
541 if (!actual_type)
542 actual_type = "";
544 if (strcmp(actual_type, accepted_type)) {
545 http_status(hdr, 415, "Unsupported Media Type");
546 hdr_nocache(hdr);
547 end_headers(hdr);
548 format_write(1,
549 "Expected POST with Content-Type '%s',"
550 " but received '%s' instead.\n",
551 accepted_type, actual_type);
552 exit(0);
556 static void service_rpc(struct strbuf *hdr, char *service_name)
558 const char *argv[] = {NULL, "--stateless-rpc", ".", NULL};
559 struct rpc_service *svc = select_service(hdr, service_name);
560 struct strbuf buf = STRBUF_INIT;
562 strbuf_reset(&buf);
563 strbuf_addf(&buf, "application/x-git-%s-request", svc->name);
564 check_content_type(hdr, buf.buf);
566 hdr_nocache(hdr);
568 strbuf_reset(&buf);
569 strbuf_addf(&buf, "application/x-git-%s-result", svc->name);
570 hdr_str(hdr, content_type, buf.buf);
572 end_headers(hdr);
574 argv[0] = svc->name;
575 run_service(argv, svc->buffer_input);
576 strbuf_release(&buf);
579 static int dead;
580 static NORETURN void die_webcgi(const char *err, va_list params)
582 if (dead <= 1) {
583 struct strbuf hdr = STRBUF_INIT;
585 vreportf("fatal: ", err, params);
587 http_status(&hdr, 500, "Internal Server Error");
588 hdr_nocache(&hdr);
589 end_headers(&hdr);
591 exit(0); /* we successfully reported a failure ;-) */
594 static int die_webcgi_recursing(void)
596 return dead++ > 1;
599 static char* getdir(void)
601 struct strbuf buf = STRBUF_INIT;
602 char *pathinfo = getenv("PATH_INFO");
603 char *root = getenv("GIT_PROJECT_ROOT");
604 char *path = getenv("PATH_TRANSLATED");
606 if (root && *root) {
607 if (!pathinfo || !*pathinfo)
608 die("GIT_PROJECT_ROOT is set but PATH_INFO is not");
609 if (daemon_avoid_alias(pathinfo))
610 die("'%s': aliased", pathinfo);
611 end_url_with_slash(&buf, root);
612 if (pathinfo[0] == '/')
613 pathinfo++;
614 strbuf_addstr(&buf, pathinfo);
615 return strbuf_detach(&buf, NULL);
616 } else if (path && *path) {
617 return xstrdup(path);
618 } else
619 die("No GIT_PROJECT_ROOT or PATH_TRANSLATED from server");
620 return NULL;
623 static struct service_cmd {
624 const char *method;
625 const char *pattern;
626 void (*imp)(struct strbuf *, char *);
627 } services[] = {
628 {"GET", "/HEAD$", get_head},
629 {"GET", "/info/refs$", get_info_refs},
630 {"GET", "/objects/info/alternates$", get_text_file},
631 {"GET", "/objects/info/http-alternates$", get_text_file},
632 {"GET", "/objects/info/packs$", get_info_packs},
633 {"GET", "/objects/[0-9a-f]{2}/[0-9a-f]{38}$", get_loose_object},
634 {"GET", "/objects/pack/pack-[0-9a-f]{40}\\.pack$", get_pack_file},
635 {"GET", "/objects/pack/pack-[0-9a-f]{40}\\.idx$", get_idx_file},
637 {"POST", "/git-upload-pack$", service_rpc},
638 {"POST", "/git-receive-pack$", service_rpc}
641 static int bad_request(struct strbuf *hdr, const struct service_cmd *c)
643 const char *proto = getenv("SERVER_PROTOCOL");
645 if (proto && !strcmp(proto, "HTTP/1.1")) {
646 http_status(hdr, 405, "Method Not Allowed");
647 hdr_str(hdr, "Allow",
648 !strcmp(c->method, "GET") ? "GET, HEAD" : c->method);
649 } else
650 http_status(hdr, 400, "Bad Request");
651 hdr_nocache(hdr);
652 end_headers(hdr);
653 return 0;
656 int cmd_main(int argc, const char **argv)
658 char *method = getenv("REQUEST_METHOD");
659 char *dir;
660 struct service_cmd *cmd = NULL;
661 char *cmd_arg = NULL;
662 int i;
663 struct strbuf hdr = STRBUF_INIT;
665 set_die_routine(die_webcgi);
666 set_die_is_recursing_routine(die_webcgi_recursing);
668 if (!method)
669 die("No REQUEST_METHOD from server");
670 if (!strcmp(method, "HEAD"))
671 method = "GET";
672 dir = getdir();
674 for (i = 0; i < ARRAY_SIZE(services); i++) {
675 struct service_cmd *c = &services[i];
676 regex_t re;
677 regmatch_t out[1];
679 if (regcomp(&re, c->pattern, REG_EXTENDED))
680 die("Bogus regex in service table: %s", c->pattern);
681 if (!regexec(&re, dir, 1, out, 0)) {
682 size_t n;
684 if (strcmp(method, c->method))
685 return bad_request(&hdr, c);
687 cmd = c;
688 n = out[0].rm_eo - out[0].rm_so;
689 cmd_arg = xmemdupz(dir + out[0].rm_so + 1, n - 1);
690 dir[out[0].rm_so] = 0;
691 break;
693 regfree(&re);
696 if (!cmd)
697 not_found(&hdr, "Request not supported: '%s'", dir);
699 setup_path();
700 if (!enter_repo(dir, 0))
701 not_found(&hdr, "Not a git repository: '%s'", dir);
702 if (!getenv("GIT_HTTP_EXPORT_ALL") &&
703 access("git-daemon-export-ok", F_OK) )
704 not_found(&hdr, "Repository not exported: '%s'", dir);
706 http_config();
707 max_request_buffer = git_env_ulong("GIT_HTTP_MAX_REQUEST_BUFFER",
708 max_request_buffer);
710 cmd->imp(&hdr, cmd_arg);
711 return 0;