fb538e36789972118aa654023736d5d7a8006565
1#include "cache.h"
2#include "config.h"
3#include "pkt-line.h"
4#include "run-command.h"
5#include "strbuf.h"
6#include "string-list.h"
7#ifdef NO_INITGROUPS
9#define initgroups(x, y) (0) /* nothing */
10#endif
11static enum log_destination {
13 LOG_DESTINATION_UNSET = -1,
14 LOG_DESTINATION_NONE = 0,
15 LOG_DESTINATION_STDERR = 1,
16 LOG_DESTINATION_SYSLOG = 2,
17} log_destination = LOG_DESTINATION_UNSET;
18static int verbose;
19static int reuseaddr;
20static int informative_errors;
21static const char daemon_usage[] =
23"git daemon [--verbose] [--syslog] [--export-all]\n"
24" [--timeout=<n>] [--init-timeout=<n>] [--max-connections=<n>]\n"
25" [--strict-paths] [--base-path=<path>] [--base-path-relaxed]\n"
26" [--user-path | --user-path=<path>]\n"
27" [--interpolated-path=<path>]\n"
28" [--reuseaddr] [--pid-file=<file>]\n"
29" [--(enable|disable|allow-override|forbid-override)=<service>]\n"
30" [--access-hook=<path>]\n"
31" [--inetd | [--listen=<host_or_ipaddr>] [--port=<n>]\n"
32" [--detach] [--user=<user> [--group=<group>]]\n"
33" [--log-destination=(stderr|syslog|none)]\n"
34" [<directory>...]";
35/* List of acceptable pathname prefixes */
37static const char **ok_paths;
38static int strict_paths;
39/* If this is set, git-daemon-export-ok is not required */
41static int export_all_trees;
42/* Take all paths relative to this one if non-NULL */
44static const char *base_path;
45static const char *interpolated_path;
46static int base_path_relaxed;
47/* If defined, ~user notation is allowed and the string is inserted
49 * after ~user/. E.g. a request to git://host/~alice/frotz would
50 * go to /home/alice/pub_git/frotz with --user-path=pub_git.
51 */
52static const char *user_path;
53/* Timeout, and initial timeout */
55static unsigned int timeout;
56static unsigned int init_timeout;
57struct hostinfo {
59 struct strbuf hostname;
60 struct strbuf canon_hostname;
61 struct strbuf ip_address;
62 struct strbuf tcp_port;
63 unsigned int hostname_lookup_done:1;
64 unsigned int saw_extended_args:1;
65};
66static void lookup_hostname(struct hostinfo *hi);
68static const char *get_canon_hostname(struct hostinfo *hi)
70{
71 lookup_hostname(hi);
72 return hi->canon_hostname.buf;
73}
74static const char *get_ip_address(struct hostinfo *hi)
76{
77 lookup_hostname(hi);
78 return hi->ip_address.buf;
79}
80static void logreport(int priority, const char *err, va_list params)
82{
83 switch (log_destination) {
84 case LOG_DESTINATION_SYSLOG: {
85 char buf[1024];
86 vsnprintf(buf, sizeof(buf), err, params);
87 syslog(priority, "%s", buf);
88 break;
89 }
90 case LOG_DESTINATION_STDERR:
91 /*
92 * Since stderr is set to buffered mode, the
93 * logging of different processes will not overlap
94 * unless they overflow the (rather big) buffers.
95 */
96 fprintf(stderr, "[%"PRIuMAX"] ", (uintmax_t)getpid());
97 vfprintf(stderr, err, params);
98 fputc('\n', stderr);
99 fflush(stderr);
100 break;
101 case LOG_DESTINATION_NONE:
102 break;
103 case LOG_DESTINATION_UNSET:
104 BUG("log destination not initialized correctly");
105 }
106}
107__attribute__((format (printf, 1, 2)))
109static void logerror(const char *err, ...)
110{
111 va_list params;
112 va_start(params, err);
113 logreport(LOG_ERR, err, params);
114 va_end(params);
115}
116__attribute__((format (printf, 1, 2)))
118static void loginfo(const char *err, ...)
119{
120 va_list params;
121 if (!verbose)
122 return;
123 va_start(params, err);
124 logreport(LOG_INFO, err, params);
125 va_end(params);
126}
127static void NORETURN daemon_die(const char *err, va_list params)
129{
130 logreport(LOG_ERR, err, params);
131 exit(1);
132}
133struct expand_path_context {
135 const char *directory;
136 struct hostinfo *hostinfo;
137};
138static size_t expand_path(struct strbuf *sb, const char *placeholder, void *ctx)
140{
141 struct expand_path_context *context = ctx;
142 struct hostinfo *hi = context->hostinfo;
143 switch (placeholder[0]) {
145 case 'H':
146 strbuf_addbuf(sb, &hi->hostname);
147 return 1;
148 case 'C':
149 if (placeholder[1] == 'H') {
150 strbuf_addstr(sb, get_canon_hostname(hi));
151 return 2;
152 }
153 break;
154 case 'I':
155 if (placeholder[1] == 'P') {
156 strbuf_addstr(sb, get_ip_address(hi));
157 return 2;
158 }
159 break;
160 case 'P':
161 strbuf_addbuf(sb, &hi->tcp_port);
162 return 1;
163 case 'D':
164 strbuf_addstr(sb, context->directory);
165 return 1;
166 }
167 return 0;
168}
169static const char *path_ok(const char *directory, struct hostinfo *hi)
171{
172 static char rpath[PATH_MAX];
173 static char interp_path[PATH_MAX];
174 size_t rlen;
175 const char *path;
176 const char *dir;
177 dir = directory;
179 if (daemon_avoid_alias(dir)) {
181 logerror("'%s': aliased", dir);
182 return NULL;
183 }
184 if (*dir == '~') {
186 if (!user_path) {
187 logerror("'%s': User-path not allowed", dir);
188 return NULL;
189 }
190 if (*user_path) {
191 /* Got either "~alice" or "~alice/foo";
192 * rewrite them to "~alice/%s" or
193 * "~alice/%s/foo".
194 */
195 int namlen, restlen = strlen(dir);
196 const char *slash = strchr(dir, '/');
197 if (!slash)
198 slash = dir + restlen;
199 namlen = slash - dir;
200 restlen -= namlen;
201 loginfo("userpath <%s>, request <%s>, namlen %d, restlen %d, slash <%s>", user_path, dir, namlen, restlen, slash);
202 rlen = snprintf(rpath, sizeof(rpath), "%.*s/%s%.*s",
203 namlen, dir, user_path, restlen, slash);
204 if (rlen >= sizeof(rpath)) {
205 logerror("user-path too large: %s", rpath);
206 return NULL;
207 }
208 dir = rpath;
209 }
210 }
211 else if (interpolated_path && hi->saw_extended_args) {
212 struct strbuf expanded_path = STRBUF_INIT;
213 struct expand_path_context context;
214 context.directory = directory;
216 context.hostinfo = hi;
217 if (*dir != '/') {
219 /* Allow only absolute */
220 logerror("'%s': Non-absolute path denied (interpolated-path active)", dir);
221 return NULL;
222 }
223 strbuf_expand(&expanded_path, interpolated_path,
225 expand_path, &context);
226 rlen = strlcpy(interp_path, expanded_path.buf,
228 sizeof(interp_path));
229 if (rlen >= sizeof(interp_path)) {
230 logerror("interpolated path too large: %s",
231 interp_path);
232 return NULL;
233 }
234 strbuf_release(&expanded_path);
236 loginfo("Interpolated dir '%s'", interp_path);
237 dir = interp_path;
239 }
240 else if (base_path) {
241 if (*dir != '/') {
242 /* Allow only absolute */
243 logerror("'%s': Non-absolute path denied (base-path active)", dir);
244 return NULL;
245 }
246 rlen = snprintf(rpath, sizeof(rpath), "%s%s", base_path, dir);
247 if (rlen >= sizeof(rpath)) {
248 logerror("base-path too large: %s", rpath);
249 return NULL;
250 }
251 dir = rpath;
252 }
253 path = enter_repo(dir, strict_paths);
255 if (!path && base_path && base_path_relaxed) {
256 /*
257 * if we fail and base_path_relaxed is enabled, try without
258 * prefixing the base path
259 */
260 dir = directory;
261 path = enter_repo(dir, strict_paths);
262 }
263 if (!path) {
265 logerror("'%s' does not appear to be a git repository", dir);
266 return NULL;
267 }
268 if ( ok_paths && *ok_paths ) {
270 const char **pp;
271 int pathlen = strlen(path);
272 /* The validation is done on the paths after enter_repo
274 * appends optional {.git,.git/.git} and friends, but
275 * it does not use getcwd(). So if your /pub is
276 * a symlink to /mnt/pub, you can whitelist /pub and
277 * do not have to say /mnt/pub.
278 * Do not say /pub/.
279 */
280 for ( pp = ok_paths ; *pp ; pp++ ) {
281 int len = strlen(*pp);
282 if (len <= pathlen &&
283 !memcmp(*pp, path, len) &&
284 (path[len] == '\0' ||
285 (!strict_paths && path[len] == '/')))
286 return path;
287 }
288 }
289 else {
290 /* be backwards compatible */
291 if (!strict_paths)
292 return path;
293 }
294 logerror("'%s': not in whitelist", path);
296 return NULL; /* Fallthrough. Deny by default */
297}
298typedef int (*daemon_service_fn)(const struct argv_array *env);
300struct daemon_service {
301 const char *name;
302 const char *config_name;
303 daemon_service_fn fn;
304 int enabled;
305 int overridable;
306};
307static int daemon_error(const char *dir, const char *msg)
309{
310 if (!informative_errors)
311 msg = "access denied or repository not exported";
312 packet_write_fmt(1, "ERR %s: %s", msg, dir);
313 return -1;
314}
315static const char *access_hook;
317static int run_access_hook(struct daemon_service *service, const char *dir,
319 const char *path, struct hostinfo *hi)
320{
321 struct child_process child = CHILD_PROCESS_INIT;
322 struct strbuf buf = STRBUF_INIT;
323 const char *argv[8];
324 const char **arg = argv;
325 char *eol;
326 int seen_errors = 0;
327 *arg++ = access_hook;
329 *arg++ = service->name;
330 *arg++ = path;
331 *arg++ = hi->hostname.buf;
332 *arg++ = get_canon_hostname(hi);
333 *arg++ = get_ip_address(hi);
334 *arg++ = hi->tcp_port.buf;
335 *arg = NULL;
336 child.use_shell = 1;
338 child.argv = argv;
339 child.no_stdin = 1;
340 child.no_stderr = 1;
341 child.out = -1;
342 if (start_command(&child)) {
343 logerror("daemon access hook '%s' failed to start",
344 access_hook);
345 goto error_return;
346 }
347 if (strbuf_read(&buf, child.out, 0) < 0) {
348 logerror("failed to read from pipe to daemon access hook '%s'",
349 access_hook);
350 strbuf_reset(&buf);
351 seen_errors = 1;
352 }
353 if (close(child.out) < 0) {
354 logerror("failed to close pipe to daemon access hook '%s'",
355 access_hook);
356 seen_errors = 1;
357 }
358 if (finish_command(&child))
359 seen_errors = 1;
360 if (!seen_errors) {
362 strbuf_release(&buf);
363 return 0;
364 }
365error_return:
367 strbuf_ltrim(&buf);
368 if (!buf.len)
369 strbuf_addstr(&buf, "service rejected");
370 eol = strchr(buf.buf, '\n');
371 if (eol)
372 *eol = '\0';
373 errno = EACCES;
374 daemon_error(dir, buf.buf);
375 strbuf_release(&buf);
376 return -1;
377}
378static int run_service(const char *dir, struct daemon_service *service,
380 struct hostinfo *hi, const struct argv_array *env)
381{
382 const char *path;
383 int enabled = service->enabled;
384 struct strbuf var = STRBUF_INIT;
385 loginfo("Request %s for '%s'", service->name, dir);
387 if (!enabled && !service->overridable) {
389 logerror("'%s': service not enabled.", service->name);
390 errno = EACCES;
391 return daemon_error(dir, "service not enabled");
392 }
393 if (!(path = path_ok(dir, hi)))
395 return daemon_error(dir, "no such repository");
396 /*
398 * Security on the cheap.
399 *
400 * We want a readable HEAD, usable "objects" directory, and
401 * a "git-daemon-export-ok" flag that says that the other side
402 * is ok with us doing this.
403 *
404 * path_ok() uses enter_repo() and does whitelist checking.
405 * We only need to make sure the repository is exported.
406 */
407 if (!export_all_trees && access("git-daemon-export-ok", F_OK)) {
409 logerror("'%s': repository not exported.", path);
410 errno = EACCES;
411 return daemon_error(dir, "repository not exported");
412 }
413 if (service->overridable) {
415 strbuf_addf(&var, "daemon.%s", service->config_name);
416 git_config_get_bool(var.buf, &enabled);
417 strbuf_release(&var);
418 }
419 if (!enabled) {
420 logerror("'%s': service not enabled for '%s'",
421 service->name, path);
422 errno = EACCES;
423 return daemon_error(dir, "service not enabled");
424 }
425 /*
427 * Optionally, a hook can choose to deny access to the
428 * repository depending on the phase of the moon.
429 */
430 if (access_hook && run_access_hook(service, dir, path, hi))
431 return -1;
432 /*
434 * We'll ignore SIGTERM from now on, we have a
435 * good client.
436 */
437 signal(SIGTERM, SIG_IGN);
438 return service->fn(env);
440}
441static void copy_to_log(int fd)
443{
444 struct strbuf line = STRBUF_INIT;
445 FILE *fp;
446 fp = fdopen(fd, "r");
448 if (fp == NULL) {
449 logerror("fdopen of error channel failed");
450 close(fd);
451 return;
452 }
453 while (strbuf_getline_lf(&line, fp) != EOF) {
455 logerror("%s", line.buf);
456 strbuf_setlen(&line, 0);
457 }
458 strbuf_release(&line);
460 fclose(fp);
461}
462static int run_service_command(struct child_process *cld)
464{
465 argv_array_push(&cld->args, ".");
466 cld->git_cmd = 1;
467 cld->err = -1;
468 if (start_command(cld))
469 return -1;
470 close(0);
472 close(1);
473 copy_to_log(cld->err);
475 return finish_command(cld);
477}
478static int upload_pack(const struct argv_array *env)
480{
481 struct child_process cld = CHILD_PROCESS_INIT;
482 argv_array_pushl(&cld.args, "upload-pack", "--strict", NULL);
483 argv_array_pushf(&cld.args, "--timeout=%u", timeout);
484 argv_array_pushv(&cld.env_array, env->argv);
486 return run_service_command(&cld);
488}
489static int upload_archive(const struct argv_array *env)
491{
492 struct child_process cld = CHILD_PROCESS_INIT;
493 argv_array_push(&cld.args, "upload-archive");
494 argv_array_pushv(&cld.env_array, env->argv);
496 return run_service_command(&cld);
498}
499static int receive_pack(const struct argv_array *env)
501{
502 struct child_process cld = CHILD_PROCESS_INIT;
503 argv_array_push(&cld.args, "receive-pack");
504 argv_array_pushv(&cld.env_array, env->argv);
506 return run_service_command(&cld);
508}
509static struct daemon_service daemon_service[] = {
511 { "upload-archive", "uploadarch", upload_archive, 0, 1 },
512 { "upload-pack", "uploadpack", upload_pack, 1, 1 },
513 { "receive-pack", "receivepack", receive_pack, 0, 1 },
514};
515static void enable_service(const char *name, int ena)
517{
518 int i;
519 for (i = 0; i < ARRAY_SIZE(daemon_service); i++) {
520 if (!strcmp(daemon_service[i].name, name)) {
521 daemon_service[i].enabled = ena;
522 return;
523 }
524 }
525 die("No such service %s", name);
526}
527static void make_service_overridable(const char *name, int ena)
529{
530 int i;
531 for (i = 0; i < ARRAY_SIZE(daemon_service); i++) {
532 if (!strcmp(daemon_service[i].name, name)) {
533 daemon_service[i].overridable = ena;
534 return;
535 }
536 }
537 die("No such service %s", name);
538}
539static void parse_host_and_port(char *hostport, char **host,
541 char **port)
542{
543 if (*hostport == '[') {
544 char *end;
545 end = strchr(hostport, ']');
547 if (!end)
548 die("Invalid request ('[' without ']')");
549 *end = '\0';
550 *host = hostport + 1;
551 if (!end[1])
552 *port = NULL;
553 else if (end[1] == ':')
554 *port = end + 2;
555 else
556 die("Garbage after end of host part");
557 } else {
558 *host = hostport;
559 *port = strrchr(hostport, ':');
560 if (*port) {
561 **port = '\0';
562 ++*port;
563 }
564 }
565}
566/*
568 * Sanitize a string from the client so that it's OK to be inserted into a
569 * filesystem path. Specifically, we disallow slashes, runs of "..", and
570 * trailing and leading dots, which means that the client cannot escape
571 * our base path via ".." traversal.
572 */
573static void sanitize_client(struct strbuf *out, const char *in)
574{
575 for (; *in; in++) {
576 if (*in == '/')
577 continue;
578 if (*in == '.' && (!out->len || out->buf[out->len - 1] == '.'))
579 continue;
580 strbuf_addch(out, *in);
581 }
582 while (out->len && out->buf[out->len - 1] == '.')
584 strbuf_setlen(out, out->len - 1);
585}
586/*
588 * Like sanitize_client, but we also perform any canonicalization
589 * to make life easier on the admin.
590 */
591static void canonicalize_client(struct strbuf *out, const char *in)
592{
593 sanitize_client(out, in);
594 strbuf_tolower(out);
595}
596/*
598 * Read the host as supplied by the client connection.
599 *
600 * Returns a pointer to the character after the NUL byte terminating the host
601 * arguemnt, or 'extra_args' if there is no host arguemnt.
602 */
603static char *parse_host_arg(struct hostinfo *hi, char *extra_args, int buflen)
604{
605 char *val;
606 int vallen;
607 char *end = extra_args + buflen;
608 if (extra_args < end && *extra_args) {
610 hi->saw_extended_args = 1;
611 if (strncasecmp("host=", extra_args, 5) == 0) {
612 val = extra_args + 5;
613 vallen = strlen(val) + 1;
614 if (*val) {
615 /* Split <host>:<port> at colon. */
616 char *host;
617 char *port;
618 parse_host_and_port(val, &host, &port);
619 if (port)
620 sanitize_client(&hi->tcp_port, port);
621 canonicalize_client(&hi->hostname, host);
622 hi->hostname_lookup_done = 0;
623 }
624 /* On to the next one */
626 extra_args = val + vallen;
627 }
628 if (extra_args < end && *extra_args)
629 die("Invalid request");
630 }
631 return extra_args;
633}
634static void parse_extra_args(struct hostinfo *hi, struct argv_array *env,
636 char *extra_args, int buflen)
637{
638 const char *end = extra_args + buflen;
639 struct strbuf git_protocol = STRBUF_INIT;
640 /* First look for the host argument */
642 extra_args = parse_host_arg(hi, extra_args, buflen);
643 /* Look for additional arguments places after a second NUL byte */
645 for (; extra_args < end; extra_args += strlen(extra_args) + 1) {
646 const char *arg = extra_args;
647 /*
649 * Parse the extra arguments, adding most to 'git_protocol'
650 * which will be used to set the 'GIT_PROTOCOL' envvar in the
651 * service that will be run.
652 *
653 * If there ends up being a particular arg in the future that
654 * git-daemon needs to parse specificly (like the 'host' arg)
655 * then it can be parsed here and not added to 'git_protocol'.
656 */
657 if (*arg) {
658 if (git_protocol.len > 0)
659 strbuf_addch(&git_protocol, ':');
660 strbuf_addstr(&git_protocol, arg);
661 }
662 }
663 if (git_protocol.len > 0)
665 argv_array_pushf(env, GIT_PROTOCOL_ENVIRONMENT "=%s",
666 git_protocol.buf);
667 strbuf_release(&git_protocol);
668}
669/*
671 * Locate canonical hostname and its IP address.
672 */
673static void lookup_hostname(struct hostinfo *hi)
674{
675 if (!hi->hostname_lookup_done && hi->hostname.len) {
676#ifndef NO_IPV6
677 struct addrinfo hints;
678 struct addrinfo *ai;
679 int gai;
680 static char addrbuf[HOST_NAME_MAX + 1];
681 memset(&hints, 0, sizeof(hints));
683 hints.ai_flags = AI_CANONNAME;
684 gai = getaddrinfo(hi->hostname.buf, NULL, &hints, &ai);
686 if (!gai) {
687 struct sockaddr_in *sin_addr = (void *)ai->ai_addr;
688 inet_ntop(AF_INET, &sin_addr->sin_addr,
690 addrbuf, sizeof(addrbuf));
691 strbuf_addstr(&hi->ip_address, addrbuf);
692 if (ai->ai_canonname)
694 sanitize_client(&hi->canon_hostname,
695 ai->ai_canonname);
696 else
697 strbuf_addbuf(&hi->canon_hostname,
698 &hi->ip_address);
699 freeaddrinfo(ai);
701 }
702#else
703 struct hostent *hent;
704 struct sockaddr_in sa;
705 char **ap;
706 static char addrbuf[HOST_NAME_MAX + 1];
707 hent = gethostbyname(hi->hostname.buf);
709 if (hent) {
710 ap = hent->h_addr_list;
711 memset(&sa, 0, sizeof sa);
712 sa.sin_family = hent->h_addrtype;
713 sa.sin_port = htons(0);
714 memcpy(&sa.sin_addr, *ap, hent->h_length);
715 inet_ntop(hent->h_addrtype, &sa.sin_addr,
717 addrbuf, sizeof(addrbuf));
718 sanitize_client(&hi->canon_hostname, hent->h_name);
720 strbuf_addstr(&hi->ip_address, addrbuf);
721 }
722#endif
723 hi->hostname_lookup_done = 1;
724 }
725}
726static void hostinfo_init(struct hostinfo *hi)
728{
729 memset(hi, 0, sizeof(*hi));
730 strbuf_init(&hi->hostname, 0);
731 strbuf_init(&hi->canon_hostname, 0);
732 strbuf_init(&hi->ip_address, 0);
733 strbuf_init(&hi->tcp_port, 0);
734}
735static void hostinfo_clear(struct hostinfo *hi)
737{
738 strbuf_release(&hi->hostname);
739 strbuf_release(&hi->canon_hostname);
740 strbuf_release(&hi->ip_address);
741 strbuf_release(&hi->tcp_port);
742}
743static void set_keep_alive(int sockfd)
745{
746 int ka = 1;
747 if (setsockopt(sockfd, SOL_SOCKET, SO_KEEPALIVE, &ka, sizeof(ka)) < 0) {
749 if (errno != ENOTSOCK)
750 logerror("unable to set SO_KEEPALIVE on socket: %s",
751 strerror(errno));
752 }
753}
754static int execute(void)
756{
757 char *line = packet_buffer;
758 int pktlen, len, i;
759 char *addr = getenv("REMOTE_ADDR"), *port = getenv("REMOTE_PORT");
760 struct hostinfo hi;
761 struct argv_array env = ARGV_ARRAY_INIT;
762 hostinfo_init(&hi);
764 if (addr)
766 loginfo("Connection from %s:%s", addr, port);
767 set_keep_alive(0);
769 alarm(init_timeout ? init_timeout : timeout);
770 pktlen = packet_read(0, NULL, NULL, packet_buffer, sizeof(packet_buffer), 0);
771 alarm(0);
772 len = strlen(line);
774 if (pktlen != len)
775 loginfo("Extended attributes (%d bytes) exist <%.*s>",
776 (int) pktlen - len,
777 (int) pktlen - len, line + len + 1);
778 if (len && line[len-1] == '\n') {
779 line[--len] = 0;
780 pktlen--;
781 }
782 /* parse additional args hidden behind a NUL byte */
784 if (len != pktlen)
785 parse_extra_args(&hi, &env, line + len + 1, pktlen - len - 1);
786 for (i = 0; i < ARRAY_SIZE(daemon_service); i++) {
788 struct daemon_service *s = &(daemon_service[i]);
789 const char *arg;
790 if (skip_prefix(line, "git-", &arg) &&
792 skip_prefix(arg, s->name, &arg) &&
793 *arg++ == ' ') {
794 /*
795 * Note: The directory here is probably context sensitive,
796 * and might depend on the actual service being performed.
797 */
798 int rc = run_service(arg, s, &hi, &env);
799 hostinfo_clear(&hi);
800 argv_array_clear(&env);
801 return rc;
802 }
803 }
804 hostinfo_clear(&hi);
806 argv_array_clear(&env);
807 logerror("Protocol error: '%s'", line);
808 return -1;
809}
810static int addrcmp(const struct sockaddr_storage *s1,
812 const struct sockaddr_storage *s2)
813{
814 const struct sockaddr *sa1 = (const struct sockaddr*) s1;
815 const struct sockaddr *sa2 = (const struct sockaddr*) s2;
816 if (sa1->sa_family != sa2->sa_family)
818 return sa1->sa_family - sa2->sa_family;
819 if (sa1->sa_family == AF_INET)
820 return memcmp(&((struct sockaddr_in *)s1)->sin_addr,
821 &((struct sockaddr_in *)s2)->sin_addr,
822 sizeof(struct in_addr));
823#ifndef NO_IPV6
824 if (sa1->sa_family == AF_INET6)
825 return memcmp(&((struct sockaddr_in6 *)s1)->sin6_addr,
826 &((struct sockaddr_in6 *)s2)->sin6_addr,
827 sizeof(struct in6_addr));
828#endif
829 return 0;
830}
831static int max_connections = 32;
833static unsigned int live_children;
835static struct child {
837 struct child *next;
838 struct child_process cld;
839 struct sockaddr_storage address;
840} *firstborn;
841static void add_child(struct child_process *cld, struct sockaddr *addr, socklen_t addrlen)
843{
844 struct child *newborn, **cradle;
845 newborn = xcalloc(1, sizeof(*newborn));
847 live_children++;
848 memcpy(&newborn->cld, cld, sizeof(*cld));
849 memcpy(&newborn->address, addr, addrlen);
850 for (cradle = &firstborn; *cradle; cradle = &(*cradle)->next)
851 if (!addrcmp(&(*cradle)->address, &newborn->address))
852 break;
853 newborn->next = *cradle;
854 *cradle = newborn;
855}
856/*
858 * This gets called if the number of connections grows
859 * past "max_connections".
860 *
861 * We kill the newest connection from a duplicate IP.
862 */
863static void kill_some_child(void)
864{
865 const struct child *blanket, *next;
866 if (!(blanket = firstborn))
868 return;
869 for (; (next = blanket->next); blanket = next)
871 if (!addrcmp(&blanket->address, &next->address)) {
872 kill(blanket->cld.pid, SIGTERM);
873 break;
874 }
875}
876static void check_dead_children(void)
878{
879 int status;
880 pid_t pid;
881 struct child **cradle, *blanket;
883 for (cradle = &firstborn; (blanket = *cradle);)
884 if ((pid = waitpid(blanket->cld.pid, &status, WNOHANG)) > 1) {
885 const char *dead = "";
886 if (status)
887 dead = " (with error)";
888 loginfo("[%"PRIuMAX"] Disconnected%s", (uintmax_t)pid, dead);
889 /* remove the child */
891 *cradle = blanket->next;
892 live_children--;
893 child_process_clear(&blanket->cld);
894 free(blanket);
895 } else
896 cradle = &blanket->next;
897}
898static struct argv_array cld_argv = ARGV_ARRAY_INIT;
900static void handle(int incoming, struct sockaddr *addr, socklen_t addrlen)
901{
902 struct child_process cld = CHILD_PROCESS_INIT;
903 if (max_connections && live_children >= max_connections) {
905 kill_some_child();
906 sleep(1); /* give it some time to die */
907 check_dead_children();
908 if (live_children >= max_connections) {
909 close(incoming);
910 logerror("Too many children, dropping connection");
911 return;
912 }
913 }
914 if (addr->sa_family == AF_INET) {
916 char buf[128] = "";
917 struct sockaddr_in *sin_addr = (void *) addr;
918 inet_ntop(addr->sa_family, &sin_addr->sin_addr, buf, sizeof(buf));
919 argv_array_pushf(&cld.env_array, "REMOTE_ADDR=%s", buf);
920 argv_array_pushf(&cld.env_array, "REMOTE_PORT=%d",
921 ntohs(sin_addr->sin_port));
922#ifndef NO_IPV6
923 } else if (addr->sa_family == AF_INET6) {
924 char buf[128] = "";
925 struct sockaddr_in6 *sin6_addr = (void *) addr;
926 inet_ntop(AF_INET6, &sin6_addr->sin6_addr, buf, sizeof(buf));
927 argv_array_pushf(&cld.env_array, "REMOTE_ADDR=[%s]", buf);
928 argv_array_pushf(&cld.env_array, "REMOTE_PORT=%d",
929 ntohs(sin6_addr->sin6_port));
930#endif
931 }
932 cld.argv = cld_argv.argv;
934 cld.in = incoming;
935 cld.out = dup(incoming);
936 if (start_command(&cld))
938 logerror("unable to fork");
939 else
940 add_child(&cld, addr, addrlen);
941}
942static void child_handler(int signo)
944{
945 /*
946 * Otherwise empty handler because systemcalls will get interrupted
947 * upon signal receipt
948 * SysV needs the handler to be rearmed
949 */
950 signal(SIGCHLD, child_handler);
951}
952static int set_reuse_addr(int sockfd)
954{
955 int on = 1;
956 if (!reuseaddr)
958 return 0;
959 return setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR,
960 &on, sizeof(on));
961}
962struct socketlist {
964 int *list;
965 size_t nr;
966 size_t alloc;
967};
968static const char *ip2str(int family, struct sockaddr *sin, socklen_t len)
970{
971#ifdef NO_IPV6
972 static char ip[INET_ADDRSTRLEN];
973#else
974 static char ip[INET6_ADDRSTRLEN];
975#endif
976 switch (family) {
978#ifndef NO_IPV6
979 case AF_INET6:
980 inet_ntop(family, &((struct sockaddr_in6*)sin)->sin6_addr, ip, len);
981 break;
982#endif
983 case AF_INET:
984 inet_ntop(family, &((struct sockaddr_in*)sin)->sin_addr, ip, len);
985 break;
986 default:
987 xsnprintf(ip, sizeof(ip), "<unknown>");
988 }
989 return ip;
990}
991#ifndef NO_IPV6
993static int setup_named_sock(char *listen_addr, int listen_port, struct socketlist *socklist)
995{
996 int socknum = 0;
997 char pbuf[NI_MAXSERV];
998 struct addrinfo hints, *ai0, *ai;
999 int gai;
1000 long flags;
1001 xsnprintf(pbuf, sizeof(pbuf), "%d", listen_port);
1003 memset(&hints, 0, sizeof(hints));
1004 hints.ai_family = AF_UNSPEC;
1005 hints.ai_socktype = SOCK_STREAM;
1006 hints.ai_protocol = IPPROTO_TCP;
1007 hints.ai_flags = AI_PASSIVE;
1008 gai = getaddrinfo(listen_addr, pbuf, &hints, &ai0);
1010 if (gai) {
1011 logerror("getaddrinfo() for %s failed: %s", listen_addr, gai_strerror(gai));
1012 return 0;
1013 }
1014 for (ai = ai0; ai; ai = ai->ai_next) {
1016 int sockfd;
1017 sockfd = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1019 if (sockfd < 0)
1020 continue;
1021 if (sockfd >= FD_SETSIZE) {
1022 logerror("Socket descriptor too large");
1023 close(sockfd);
1024 continue;
1025 }
1026#ifdef IPV6_V6ONLY
1028 if (ai->ai_family == AF_INET6) {
1029 int on = 1;
1030 setsockopt(sockfd, IPPROTO_IPV6, IPV6_V6ONLY,
1031 &on, sizeof(on));
1032 /* Note: error is not fatal */
1033 }
1034#endif
1035 if (set_reuse_addr(sockfd)) {
1037 logerror("Could not set SO_REUSEADDR: %s", strerror(errno));
1038 close(sockfd);
1039 continue;
1040 }
1041 set_keep_alive(sockfd);
1043 if (bind(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
1045 logerror("Could not bind to %s: %s",
1046 ip2str(ai->ai_family, ai->ai_addr, ai->ai_addrlen),
1047 strerror(errno));
1048 close(sockfd);
1049 continue; /* not fatal */
1050 }
1051 if (listen(sockfd, 5) < 0) {
1052 logerror("Could not listen to %s: %s",
1053 ip2str(ai->ai_family, ai->ai_addr, ai->ai_addrlen),
1054 strerror(errno));
1055 close(sockfd);
1056 continue; /* not fatal */
1057 }
1058 flags = fcntl(sockfd, F_GETFD, 0);
1060 if (flags >= 0)
1061 fcntl(sockfd, F_SETFD, flags | FD_CLOEXEC);
1062 ALLOC_GROW(socklist->list, socklist->nr + 1, socklist->alloc);
1064 socklist->list[socklist->nr++] = sockfd;
1065 socknum++;
1066 }
1067 freeaddrinfo(ai0);
1069 return socknum;
1071}
1072#else /* NO_IPV6 */
1074static int setup_named_sock(char *listen_addr, int listen_port, struct socketlist *socklist)
1076{
1077 struct sockaddr_in sin;
1078 int sockfd;
1079 long flags;
1080 memset(&sin, 0, sizeof sin);
1082 sin.sin_family = AF_INET;
1083 sin.sin_port = htons(listen_port);
1084 if (listen_addr) {
1086 /* Well, host better be an IP address here. */
1087 if (inet_pton(AF_INET, listen_addr, &sin.sin_addr.s_addr) <= 0)
1088 return 0;
1089 } else {
1090 sin.sin_addr.s_addr = htonl(INADDR_ANY);
1091 }
1092 sockfd = socket(AF_INET, SOCK_STREAM, 0);
1094 if (sockfd < 0)
1095 return 0;
1096 if (set_reuse_addr(sockfd)) {
1098 logerror("Could not set SO_REUSEADDR: %s", strerror(errno));
1099 close(sockfd);
1100 return 0;
1101 }
1102 set_keep_alive(sockfd);
1104 if ( bind(sockfd, (struct sockaddr *)&sin, sizeof sin) < 0 ) {
1106 logerror("Could not bind to %s: %s",
1107 ip2str(AF_INET, (struct sockaddr *)&sin, sizeof(sin)),
1108 strerror(errno));
1109 close(sockfd);
1110 return 0;
1111 }
1112 if (listen(sockfd, 5) < 0) {
1114 logerror("Could not listen to %s: %s",
1115 ip2str(AF_INET, (struct sockaddr *)&sin, sizeof(sin)),
1116 strerror(errno));
1117 close(sockfd);
1118 return 0;
1119 }
1120 flags = fcntl(sockfd, F_GETFD, 0);
1122 if (flags >= 0)
1123 fcntl(sockfd, F_SETFD, flags | FD_CLOEXEC);
1124 ALLOC_GROW(socklist->list, socklist->nr + 1, socklist->alloc);
1126 socklist->list[socklist->nr++] = sockfd;
1127 return 1;
1128}
1129#endif
1131static void socksetup(struct string_list *listen_addr, int listen_port, struct socketlist *socklist)
1133{
1134 if (!listen_addr->nr)
1135 setup_named_sock(NULL, listen_port, socklist);
1136 else {
1137 int i, socknum;
1138 for (i = 0; i < listen_addr->nr; i++) {
1139 socknum = setup_named_sock(listen_addr->items[i].string,
1140 listen_port, socklist);
1141 if (socknum == 0)
1143 logerror("unable to allocate any listen sockets for host %s on port %u",
1144 listen_addr->items[i].string, listen_port);
1145 }
1146 }
1147}
1148static int service_loop(struct socketlist *socklist)
1150{
1151 struct pollfd *pfd;
1152 int i;
1153 pfd = xcalloc(socklist->nr, sizeof(struct pollfd));
1155 for (i = 0; i < socklist->nr; i++) {
1157 pfd[i].fd = socklist->list[i];
1158 pfd[i].events = POLLIN;
1159 }
1160 signal(SIGCHLD, child_handler);
1162 for (;;) {
1164 int i;
1165 check_dead_children();
1167 if (poll(pfd, socklist->nr, -1) < 0) {
1169 if (errno != EINTR) {
1170 logerror("Poll failed, resuming: %s",
1171 strerror(errno));
1172 sleep(1);
1173 }
1174 continue;
1175 }
1176 for (i = 0; i < socklist->nr; i++) {
1178 if (pfd[i].revents & POLLIN) {
1179 union {
1180 struct sockaddr sa;
1181 struct sockaddr_in sai;
1182#ifndef NO_IPV6
1183 struct sockaddr_in6 sai6;
1184#endif
1185 } ss;
1186 socklen_t sslen = sizeof(ss);
1187 int incoming = accept(pfd[i].fd, &ss.sa, &sslen);
1188 if (incoming < 0) {
1189 switch (errno) {
1190 case EAGAIN:
1191 case EINTR:
1192 case ECONNABORTED:
1193 continue;
1194 default:
1195 die_errno("accept returned");
1196 }
1197 }
1198 handle(incoming, &ss.sa, sslen);
1199 }
1200 }
1201 }
1202}
1203#ifdef NO_POSIX_GOODIES
1205struct credentials;
1207static void drop_privileges(struct credentials *cred)
1209{
1210 /* nothing */
1211}
1212static struct credentials *prepare_credentials(const char *user_name,
1214 const char *group_name)
1215{
1216 die("--user not supported on this platform");
1217}
1218#else
1220struct credentials {
1222 struct passwd *pass;
1223 gid_t gid;
1224};
1225static void drop_privileges(struct credentials *cred)
1227{
1228 if (cred && (initgroups(cred->pass->pw_name, cred->gid) ||
1229 setgid (cred->gid) || setuid(cred->pass->pw_uid)))
1230 die("cannot drop privileges");
1231}
1232static struct credentials *prepare_credentials(const char *user_name,
1234 const char *group_name)
1235{
1236 static struct credentials c;
1237 c.pass = getpwnam(user_name);
1239 if (!c.pass)
1240 die("user not found - %s", user_name);
1241 if (!group_name)
1243 c.gid = c.pass->pw_gid;
1244 else {
1245 struct group *group = getgrnam(group_name);
1246 if (!group)
1247 die("group not found - %s", group_name);
1248 c.gid = group->gr_gid;
1250 }
1251 return &c;
1253}
1254#endif
1255static int serve(struct string_list *listen_addr, int listen_port,
1257 struct credentials *cred)
1258{
1259 struct socketlist socklist = { NULL, 0, 0 };
1260 socksetup(listen_addr, listen_port, &socklist);
1262 if (socklist.nr == 0)
1263 die("unable to allocate any listen sockets on port %u",
1264 listen_port);
1265 drop_privileges(cred);
1267 loginfo("Ready to rumble");
1269 return service_loop(&socklist);
1271}
1272int cmd_main(int argc, const char **argv)
1274{
1275 int listen_port = 0;
1276 struct string_list listen_addr = STRING_LIST_INIT_NODUP;
1277 int serve_mode = 0, inetd_mode = 0;
1278 const char *pid_file = NULL, *user_name = NULL, *group_name = NULL;
1279 int detach = 0;
1280 struct credentials *cred = NULL;
1281 int i;
1282 for (i = 1; i < argc; i++) {
1284 const char *arg = argv[i];
1285 const char *v;
1286 if (skip_prefix(arg, "--listen=", &v)) {
1288 string_list_append(&listen_addr, xstrdup_tolower(v));
1289 continue;
1290 }
1291 if (skip_prefix(arg, "--port=", &v)) {
1292 char *end;
1293 unsigned long n;
1294 n = strtoul(v, &end, 0);
1295 if (*v && !*end) {
1296 listen_port = n;
1297 continue;
1298 }
1299 }
1300 if (!strcmp(arg, "--serve")) {
1301 serve_mode = 1;
1302 continue;
1303 }
1304 if (!strcmp(arg, "--inetd")) {
1305 inetd_mode = 1;
1306 continue;
1307 }
1308 if (!strcmp(arg, "--verbose")) {
1309 verbose = 1;
1310 continue;
1311 }
1312 if (!strcmp(arg, "--syslog")) {
1313 log_destination = LOG_DESTINATION_SYSLOG;
1314 continue;
1315 }
1316 if (skip_prefix(arg, "--log-destination=", &v)) {
1317 if (!strcmp(v, "syslog")) {
1318 log_destination = LOG_DESTINATION_SYSLOG;
1319 continue;
1320 } else if (!strcmp(v, "stderr")) {
1321 log_destination = LOG_DESTINATION_STDERR;
1322 continue;
1323 } else if (!strcmp(v, "none")) {
1324 log_destination = LOG_DESTINATION_NONE;
1325 continue;
1326 } else
1327 die("unknown log destination '%s'", v);
1328 }
1329 if (!strcmp(arg, "--export-all")) {
1330 export_all_trees = 1;
1331 continue;
1332 }
1333 if (skip_prefix(arg, "--access-hook=", &v)) {
1334 access_hook = v;
1335 continue;
1336 }
1337 if (skip_prefix(arg, "--timeout=", &v)) {
1338 timeout = atoi(v);
1339 continue;
1340 }
1341 if (skip_prefix(arg, "--init-timeout=", &v)) {
1342 init_timeout = atoi(v);
1343 continue;
1344 }
1345 if (skip_prefix(arg, "--max-connections=", &v)) {
1346 max_connections = atoi(v);
1347 if (max_connections < 0)
1348 max_connections = 0; /* unlimited */
1349 continue;
1350 }
1351 if (!strcmp(arg, "--strict-paths")) {
1352 strict_paths = 1;
1353 continue;
1354 }
1355 if (skip_prefix(arg, "--base-path=", &v)) {
1356 base_path = v;
1357 continue;
1358 }
1359 if (!strcmp(arg, "--base-path-relaxed")) {
1360 base_path_relaxed = 1;
1361 continue;
1362 }
1363 if (skip_prefix(arg, "--interpolated-path=", &v)) {
1364 interpolated_path = v;
1365 continue;
1366 }
1367 if (!strcmp(arg, "--reuseaddr")) {
1368 reuseaddr = 1;
1369 continue;
1370 }
1371 if (!strcmp(arg, "--user-path")) {
1372 user_path = "";
1373 continue;
1374 }
1375 if (skip_prefix(arg, "--user-path=", &v)) {
1376 user_path = v;
1377 continue;
1378 }
1379 if (skip_prefix(arg, "--pid-file=", &v)) {
1380 pid_file = v;
1381 continue;
1382 }
1383 if (!strcmp(arg, "--detach")) {
1384 detach = 1;
1385 continue;
1386 }
1387 if (skip_prefix(arg, "--user=", &v)) {
1388 user_name = v;
1389 continue;
1390 }
1391 if (skip_prefix(arg, "--group=", &v)) {
1392 group_name = v;
1393 continue;
1394 }
1395 if (skip_prefix(arg, "--enable=", &v)) {
1396 enable_service(v, 1);
1397 continue;
1398 }
1399 if (skip_prefix(arg, "--disable=", &v)) {
1400 enable_service(v, 0);
1401 continue;
1402 }
1403 if (skip_prefix(arg, "--allow-override=", &v)) {
1404 make_service_overridable(v, 1);
1405 continue;
1406 }
1407 if (skip_prefix(arg, "--forbid-override=", &v)) {
1408 make_service_overridable(v, 0);
1409 continue;
1410 }
1411 if (!strcmp(arg, "--informative-errors")) {
1412 informative_errors = 1;
1413 continue;
1414 }
1415 if (!strcmp(arg, "--no-informative-errors")) {
1416 informative_errors = 0;
1417 continue;
1418 }
1419 if (!strcmp(arg, "--")) {
1420 ok_paths = &argv[i+1];
1421 break;
1422 } else if (arg[0] != '-') {
1423 ok_paths = &argv[i];
1424 break;
1425 }
1426 usage(daemon_usage);
1428 }
1429 if (log_destination == LOG_DESTINATION_UNSET) {
1431 if (inetd_mode || detach)
1432 log_destination = LOG_DESTINATION_SYSLOG;
1433 else
1434 log_destination = LOG_DESTINATION_STDERR;
1435 }
1436 if (log_destination == LOG_DESTINATION_SYSLOG) {
1438 openlog("git-daemon", LOG_PID, LOG_DAEMON);
1439 set_die_routine(daemon_die);
1440 } else
1441 /* avoid splitting a message in the middle */
1442 setvbuf(stderr, NULL, _IOFBF, 4096);
1443 if (inetd_mode && (detach || group_name || user_name))
1445 die("--detach, --user and --group are incompatible with --inetd");
1446 if (inetd_mode && (listen_port || (listen_addr.nr > 0)))
1448 die("--listen= and --port= are incompatible with --inetd");
1449 else if (listen_port == 0)
1450 listen_port = DEFAULT_GIT_PORT;
1451 if (group_name && !user_name)
1453 die("--group supplied without --user");
1454 if (user_name)
1456 cred = prepare_credentials(user_name, group_name);
1457 if (strict_paths && (!ok_paths || !*ok_paths))
1459 die("option --strict-paths requires a whitelist");
1460 if (base_path && !is_directory(base_path))
1462 die("base-path '%s' does not exist or is not a directory",
1463 base_path);
1464 if (inetd_mode) {
1466 if (!freopen("/dev/null", "w", stderr))
1467 die_errno("failed to redirect stderr to /dev/null");
1468 }
1469 if (inetd_mode || serve_mode)
1471 return execute();
1472 if (detach) {
1474 if (daemonize())
1475 die("--detach not supported on this platform");
1476 }
1477 if (pid_file)
1479 write_file(pid_file, "%"PRIuMAX, (uintmax_t) getpid());
1480 /* prepare argv for serving-processes */
1482 argv_array_push(&cld_argv, argv[0]); /* git-daemon */
1483 argv_array_push(&cld_argv, "--serve");
1484 for (i = 1; i < argc; ++i)
1485 argv_array_push(&cld_argv, argv[i]);
1486 return serve(&listen_addr, listen_port, cred);
1488}