t2400: drop no-op `--sq` from rev-parse call
[git.git] / daemon.c
blobdb8a31a6ea2145a4c3c2a44caaa82d0ed9e9c278
1 #include "cache.h"
2 #include "abspath.h"
3 #include "alloc.h"
4 #include "config.h"
5 #include "environment.h"
6 #include "pkt-line.h"
7 #include "run-command.h"
8 #include "setup.h"
9 #include "strbuf.h"
10 #include "string-list.h"
11 #include "wrapper.h"
13 #ifdef NO_INITGROUPS
14 #define initgroups(x, y) (0) /* nothing */
15 #endif
17 static enum log_destination {
18 LOG_DESTINATION_UNSET = -1,
19 LOG_DESTINATION_NONE = 0,
20 LOG_DESTINATION_STDERR = 1,
21 LOG_DESTINATION_SYSLOG = 2,
22 } log_destination = LOG_DESTINATION_UNSET;
23 static int verbose;
24 static int reuseaddr;
25 static int informative_errors;
27 static const char daemon_usage[] =
28 "git daemon [--verbose] [--syslog] [--export-all]\n"
29 " [--timeout=<n>] [--init-timeout=<n>] [--max-connections=<n>]\n"
30 " [--strict-paths] [--base-path=<path>] [--base-path-relaxed]\n"
31 " [--user-path | --user-path=<path>]\n"
32 " [--interpolated-path=<path>]\n"
33 " [--reuseaddr] [--pid-file=<file>]\n"
34 " [--(enable|disable|allow-override|forbid-override)=<service>]\n"
35 " [--access-hook=<path>]\n"
36 " [--inetd | [--listen=<host_or_ipaddr>] [--port=<n>]\n"
37 " [--detach] [--user=<user> [--group=<group>]]\n"
38 " [--log-destination=(stderr|syslog|none)]\n"
39 " [<directory>...]";
41 /* List of acceptable pathname prefixes */
42 static const char **ok_paths;
43 static int strict_paths;
45 /* If this is set, git-daemon-export-ok is not required */
46 static int export_all_trees;
48 /* Take all paths relative to this one if non-NULL */
49 static const char *base_path;
50 static const char *interpolated_path;
51 static int base_path_relaxed;
53 /* If defined, ~user notation is allowed and the string is inserted
54 * after ~user/. E.g. a request to git://host/~alice/frotz would
55 * go to /home/alice/pub_git/frotz with --user-path=pub_git.
57 static const char *user_path;
59 /* Timeout, and initial timeout */
60 static unsigned int timeout;
61 static unsigned int init_timeout;
63 struct hostinfo {
64 struct strbuf hostname;
65 struct strbuf canon_hostname;
66 struct strbuf ip_address;
67 struct strbuf tcp_port;
68 unsigned int hostname_lookup_done:1;
69 unsigned int saw_extended_args:1;
71 #define HOSTINFO_INIT { \
72 .hostname = STRBUF_INIT, \
73 .canon_hostname = STRBUF_INIT, \
74 .ip_address = STRBUF_INIT, \
75 .tcp_port = STRBUF_INIT, \
78 static void lookup_hostname(struct hostinfo *hi);
80 static const char *get_canon_hostname(struct hostinfo *hi)
82 lookup_hostname(hi);
83 return hi->canon_hostname.buf;
86 static const char *get_ip_address(struct hostinfo *hi)
88 lookup_hostname(hi);
89 return hi->ip_address.buf;
92 static void logreport(int priority, const char *err, va_list params)
94 switch (log_destination) {
95 case LOG_DESTINATION_SYSLOG: {
96 char buf[1024];
97 vsnprintf(buf, sizeof(buf), err, params);
98 syslog(priority, "%s", buf);
99 break;
101 case LOG_DESTINATION_STDERR:
103 * Since stderr is set to buffered mode, the
104 * logging of different processes will not overlap
105 * unless they overflow the (rather big) buffers.
107 fprintf(stderr, "[%"PRIuMAX"] ", (uintmax_t)getpid());
108 vfprintf(stderr, err, params);
109 fputc('\n', stderr);
110 fflush(stderr);
111 break;
112 case LOG_DESTINATION_NONE:
113 break;
114 case LOG_DESTINATION_UNSET:
115 BUG("log destination not initialized correctly");
119 __attribute__((format (printf, 1, 2)))
120 static void logerror(const char *err, ...)
122 va_list params;
123 va_start(params, err);
124 logreport(LOG_ERR, err, params);
125 va_end(params);
128 __attribute__((format (printf, 1, 2)))
129 static void loginfo(const char *err, ...)
131 va_list params;
132 if (!verbose)
133 return;
134 va_start(params, err);
135 logreport(LOG_INFO, err, params);
136 va_end(params);
139 static void NORETURN daemon_die(const char *err, va_list params)
141 logreport(LOG_ERR, err, params);
142 exit(1);
145 struct expand_path_context {
146 const char *directory;
147 struct hostinfo *hostinfo;
150 static size_t expand_path(struct strbuf *sb, const char *placeholder, void *ctx)
152 struct expand_path_context *context = ctx;
153 struct hostinfo *hi = context->hostinfo;
155 switch (placeholder[0]) {
156 case 'H':
157 strbuf_addbuf(sb, &hi->hostname);
158 return 1;
159 case 'C':
160 if (placeholder[1] == 'H') {
161 strbuf_addstr(sb, get_canon_hostname(hi));
162 return 2;
164 break;
165 case 'I':
166 if (placeholder[1] == 'P') {
167 strbuf_addstr(sb, get_ip_address(hi));
168 return 2;
170 break;
171 case 'P':
172 strbuf_addbuf(sb, &hi->tcp_port);
173 return 1;
174 case 'D':
175 strbuf_addstr(sb, context->directory);
176 return 1;
178 return 0;
181 static const char *path_ok(const char *directory, struct hostinfo *hi)
183 static char rpath[PATH_MAX];
184 static char interp_path[PATH_MAX];
185 size_t rlen;
186 const char *path;
187 const char *dir;
189 dir = directory;
191 if (daemon_avoid_alias(dir)) {
192 logerror("'%s': aliased", dir);
193 return NULL;
196 if (*dir == '~') {
197 if (!user_path) {
198 logerror("'%s': User-path not allowed", dir);
199 return NULL;
201 if (*user_path) {
202 /* Got either "~alice" or "~alice/foo";
203 * rewrite them to "~alice/%s" or
204 * "~alice/%s/foo".
206 int namlen, restlen = strlen(dir);
207 const char *slash = strchr(dir, '/');
208 if (!slash)
209 slash = dir + restlen;
210 namlen = slash - dir;
211 restlen -= namlen;
212 loginfo("userpath <%s>, request <%s>, namlen %d, restlen %d, slash <%s>", user_path, dir, namlen, restlen, slash);
213 rlen = snprintf(rpath, sizeof(rpath), "%.*s/%s%.*s",
214 namlen, dir, user_path, restlen, slash);
215 if (rlen >= sizeof(rpath)) {
216 logerror("user-path too large: %s", rpath);
217 return NULL;
219 dir = rpath;
222 else if (interpolated_path && hi->saw_extended_args) {
223 struct strbuf expanded_path = STRBUF_INIT;
224 struct expand_path_context context;
226 context.directory = directory;
227 context.hostinfo = hi;
229 if (*dir != '/') {
230 /* Allow only absolute */
231 logerror("'%s': Non-absolute path denied (interpolated-path active)", dir);
232 return NULL;
235 strbuf_expand(&expanded_path, interpolated_path,
236 expand_path, &context);
238 rlen = strlcpy(interp_path, expanded_path.buf,
239 sizeof(interp_path));
240 strbuf_release(&expanded_path);
241 if (rlen >= sizeof(interp_path)) {
242 logerror("interpolated path too large: %s",
243 interp_path);
244 return NULL;
247 loginfo("Interpolated dir '%s'", interp_path);
249 dir = interp_path;
251 else if (base_path) {
252 if (*dir != '/') {
253 /* Allow only absolute */
254 logerror("'%s': Non-absolute path denied (base-path active)", dir);
255 return NULL;
257 rlen = snprintf(rpath, sizeof(rpath), "%s%s", base_path, dir);
258 if (rlen >= sizeof(rpath)) {
259 logerror("base-path too large: %s", rpath);
260 return NULL;
262 dir = rpath;
265 path = enter_repo(dir, strict_paths);
266 if (!path && base_path && base_path_relaxed) {
268 * if we fail and base_path_relaxed is enabled, try without
269 * prefixing the base path
271 dir = directory;
272 path = enter_repo(dir, strict_paths);
275 if (!path) {
276 logerror("'%s' does not appear to be a git repository", dir);
277 return NULL;
280 if ( ok_paths && *ok_paths ) {
281 const char **pp;
282 int pathlen = strlen(path);
284 /* The validation is done on the paths after enter_repo
285 * appends optional {.git,.git/.git} and friends, but
286 * it does not use getcwd(). So if your /pub is
287 * a symlink to /mnt/pub, you can include /pub and
288 * do not have to say /mnt/pub.
289 * Do not say /pub/.
291 for ( pp = ok_paths ; *pp ; pp++ ) {
292 int len = strlen(*pp);
293 if (len <= pathlen &&
294 !memcmp(*pp, path, len) &&
295 (path[len] == '\0' ||
296 (!strict_paths && path[len] == '/')))
297 return path;
300 else {
301 /* be backwards compatible */
302 if (!strict_paths)
303 return path;
306 logerror("'%s': not in directory list", path);
307 return NULL; /* Fallthrough. Deny by default */
310 typedef int (*daemon_service_fn)(const struct strvec *env);
311 struct daemon_service {
312 const char *name;
313 const char *config_name;
314 daemon_service_fn fn;
315 int enabled;
316 int overridable;
319 static int daemon_error(const char *dir, const char *msg)
321 if (!informative_errors)
322 msg = "access denied or repository not exported";
323 packet_write_fmt(1, "ERR %s: %s", msg, dir);
324 return -1;
327 static const char *access_hook;
329 static int run_access_hook(struct daemon_service *service, const char *dir,
330 const char *path, struct hostinfo *hi)
332 struct child_process child = CHILD_PROCESS_INIT;
333 struct strbuf buf = STRBUF_INIT;
334 char *eol;
335 int seen_errors = 0;
337 strvec_push(&child.args, access_hook);
338 strvec_push(&child.args, service->name);
339 strvec_push(&child.args, path);
340 strvec_push(&child.args, hi->hostname.buf);
341 strvec_push(&child.args, get_canon_hostname(hi));
342 strvec_push(&child.args, get_ip_address(hi));
343 strvec_push(&child.args, hi->tcp_port.buf);
345 child.use_shell = 1;
346 child.no_stdin = 1;
347 child.no_stderr = 1;
348 child.out = -1;
349 if (start_command(&child)) {
350 logerror("daemon access hook '%s' failed to start",
351 access_hook);
352 goto error_return;
354 if (strbuf_read(&buf, child.out, 0) < 0) {
355 logerror("failed to read from pipe to daemon access hook '%s'",
356 access_hook);
357 strbuf_reset(&buf);
358 seen_errors = 1;
360 if (close(child.out) < 0) {
361 logerror("failed to close pipe to daemon access hook '%s'",
362 access_hook);
363 seen_errors = 1;
365 if (finish_command(&child))
366 seen_errors = 1;
368 if (!seen_errors) {
369 strbuf_release(&buf);
370 return 0;
373 error_return:
374 strbuf_ltrim(&buf);
375 if (!buf.len)
376 strbuf_addstr(&buf, "service rejected");
377 eol = strchr(buf.buf, '\n');
378 if (eol)
379 *eol = '\0';
380 errno = EACCES;
381 daemon_error(dir, buf.buf);
382 strbuf_release(&buf);
383 return -1;
386 static int run_service(const char *dir, struct daemon_service *service,
387 struct hostinfo *hi, const struct strvec *env)
389 const char *path;
390 int enabled = service->enabled;
391 struct strbuf var = STRBUF_INIT;
393 loginfo("Request %s for '%s'", service->name, dir);
395 if (!enabled && !service->overridable) {
396 logerror("'%s': service not enabled.", service->name);
397 errno = EACCES;
398 return daemon_error(dir, "service not enabled");
401 if (!(path = path_ok(dir, hi)))
402 return daemon_error(dir, "no such repository");
405 * Security on the cheap.
407 * We want a readable HEAD, usable "objects" directory, and
408 * a "git-daemon-export-ok" flag that says that the other side
409 * is ok with us doing this.
411 * path_ok() uses enter_repo() and checks for included directories.
412 * We only need to make sure the repository is exported.
415 if (!export_all_trees && access("git-daemon-export-ok", F_OK)) {
416 logerror("'%s': repository not exported.", path);
417 errno = EACCES;
418 return daemon_error(dir, "repository not exported");
421 if (service->overridable) {
422 strbuf_addf(&var, "daemon.%s", service->config_name);
423 git_config_get_bool(var.buf, &enabled);
424 strbuf_release(&var);
426 if (!enabled) {
427 logerror("'%s': service not enabled for '%s'",
428 service->name, path);
429 errno = EACCES;
430 return daemon_error(dir, "service not enabled");
434 * Optionally, a hook can choose to deny access to the
435 * repository depending on the phase of the moon.
437 if (access_hook && run_access_hook(service, dir, path, hi))
438 return -1;
441 * We'll ignore SIGTERM from now on, we have a
442 * good client.
444 signal(SIGTERM, SIG_IGN);
446 return service->fn(env);
449 static void copy_to_log(int fd)
451 struct strbuf line = STRBUF_INIT;
452 FILE *fp;
454 fp = fdopen(fd, "r");
455 if (!fp) {
456 logerror("fdopen of error channel failed");
457 close(fd);
458 return;
461 while (strbuf_getline_lf(&line, fp) != EOF) {
462 logerror("%s", line.buf);
463 strbuf_setlen(&line, 0);
466 strbuf_release(&line);
467 fclose(fp);
470 static int run_service_command(struct child_process *cld)
472 strvec_push(&cld->args, ".");
473 cld->git_cmd = 1;
474 cld->err = -1;
475 if (start_command(cld))
476 return -1;
478 close(0);
479 close(1);
481 copy_to_log(cld->err);
483 return finish_command(cld);
486 static int upload_pack(const struct strvec *env)
488 struct child_process cld = CHILD_PROCESS_INIT;
489 strvec_pushl(&cld.args, "upload-pack", "--strict", NULL);
490 strvec_pushf(&cld.args, "--timeout=%u", timeout);
492 strvec_pushv(&cld.env, env->v);
494 return run_service_command(&cld);
497 static int upload_archive(const struct strvec *env)
499 struct child_process cld = CHILD_PROCESS_INIT;
500 strvec_push(&cld.args, "upload-archive");
502 strvec_pushv(&cld.env, env->v);
504 return run_service_command(&cld);
507 static int receive_pack(const struct strvec *env)
509 struct child_process cld = CHILD_PROCESS_INIT;
510 strvec_push(&cld.args, "receive-pack");
512 strvec_pushv(&cld.env, env->v);
514 return run_service_command(&cld);
517 static struct daemon_service daemon_service[] = {
518 { "upload-archive", "uploadarch", upload_archive, 0, 1 },
519 { "upload-pack", "uploadpack", upload_pack, 1, 1 },
520 { "receive-pack", "receivepack", receive_pack, 0, 1 },
523 static void enable_service(const char *name, int ena)
525 int i;
526 for (i = 0; i < ARRAY_SIZE(daemon_service); i++) {
527 if (!strcmp(daemon_service[i].name, name)) {
528 daemon_service[i].enabled = ena;
529 return;
532 die("No such service %s", name);
535 static void make_service_overridable(const char *name, int ena)
537 int i;
538 for (i = 0; i < ARRAY_SIZE(daemon_service); i++) {
539 if (!strcmp(daemon_service[i].name, name)) {
540 daemon_service[i].overridable = ena;
541 return;
544 die("No such service %s", name);
547 static void parse_host_and_port(char *hostport, char **host,
548 char **port)
550 if (*hostport == '[') {
551 char *end;
553 end = strchr(hostport, ']');
554 if (!end)
555 die("Invalid request ('[' without ']')");
556 *end = '\0';
557 *host = hostport + 1;
558 if (!end[1])
559 *port = NULL;
560 else if (end[1] == ':')
561 *port = end + 2;
562 else
563 die("Garbage after end of host part");
564 } else {
565 *host = hostport;
566 *port = strrchr(hostport, ':');
567 if (*port) {
568 **port = '\0';
569 ++*port;
575 * Sanitize a string from the client so that it's OK to be inserted into a
576 * filesystem path. Specifically, we disallow directory separators, runs
577 * of "..", and trailing and leading dots, which means that the client
578 * cannot escape our base path via ".." traversal.
580 static void sanitize_client(struct strbuf *out, const char *in)
582 for (; *in; in++) {
583 if (is_dir_sep(*in))
584 continue;
585 if (*in == '.' && (!out->len || out->buf[out->len - 1] == '.'))
586 continue;
587 strbuf_addch(out, *in);
590 while (out->len && out->buf[out->len - 1] == '.')
591 strbuf_setlen(out, out->len - 1);
595 * Like sanitize_client, but we also perform any canonicalization
596 * to make life easier on the admin.
598 static void canonicalize_client(struct strbuf *out, const char *in)
600 sanitize_client(out, in);
601 strbuf_tolower(out);
605 * Read the host as supplied by the client connection.
607 * Returns a pointer to the character after the NUL byte terminating the host
608 * argument, or 'extra_args' if there is no host argument.
610 static char *parse_host_arg(struct hostinfo *hi, char *extra_args, int buflen)
612 char *val;
613 int vallen;
614 char *end = extra_args + buflen;
616 if (extra_args < end && *extra_args) {
617 hi->saw_extended_args = 1;
618 if (strncasecmp("host=", extra_args, 5) == 0) {
619 val = extra_args + 5;
620 vallen = strlen(val) + 1;
621 loginfo("Extended attribute \"host\": %s", val);
622 if (*val) {
623 /* Split <host>:<port> at colon. */
624 char *host;
625 char *port;
626 parse_host_and_port(val, &host, &port);
627 if (port)
628 sanitize_client(&hi->tcp_port, port);
629 canonicalize_client(&hi->hostname, host);
630 hi->hostname_lookup_done = 0;
633 /* On to the next one */
634 extra_args = val + vallen;
636 if (extra_args < end && *extra_args)
637 die("Invalid request");
640 return extra_args;
643 static void parse_extra_args(struct hostinfo *hi, struct strvec *env,
644 char *extra_args, int buflen)
646 const char *end = extra_args + buflen;
647 struct strbuf git_protocol = STRBUF_INIT;
649 /* First look for the host argument */
650 extra_args = parse_host_arg(hi, extra_args, buflen);
652 /* Look for additional arguments places after a second NUL byte */
653 for (; extra_args < end; extra_args += strlen(extra_args) + 1) {
654 const char *arg = extra_args;
657 * Parse the extra arguments, adding most to 'git_protocol'
658 * which will be used to set the 'GIT_PROTOCOL' envvar in the
659 * service that will be run.
661 * If there ends up being a particular arg in the future that
662 * git-daemon needs to parse specifically (like the 'host' arg)
663 * then it can be parsed here and not added to 'git_protocol'.
665 if (*arg) {
666 if (git_protocol.len > 0)
667 strbuf_addch(&git_protocol, ':');
668 strbuf_addstr(&git_protocol, arg);
672 if (git_protocol.len > 0) {
673 loginfo("Extended attribute \"protocol\": %s", git_protocol.buf);
674 strvec_pushf(env, GIT_PROTOCOL_ENVIRONMENT "=%s",
675 git_protocol.buf);
677 strbuf_release(&git_protocol);
681 * Locate canonical hostname and its IP address.
683 static void lookup_hostname(struct hostinfo *hi)
685 if (!hi->hostname_lookup_done && hi->hostname.len) {
686 #ifndef NO_IPV6
687 struct addrinfo hints;
688 struct addrinfo *ai;
689 int gai;
690 static char addrbuf[HOST_NAME_MAX + 1];
692 memset(&hints, 0, sizeof(hints));
693 hints.ai_flags = AI_CANONNAME;
695 gai = getaddrinfo(hi->hostname.buf, NULL, &hints, &ai);
696 if (!gai) {
697 struct sockaddr_in *sin_addr = (void *)ai->ai_addr;
699 inet_ntop(AF_INET, &sin_addr->sin_addr,
700 addrbuf, sizeof(addrbuf));
701 strbuf_addstr(&hi->ip_address, addrbuf);
703 if (ai->ai_canonname)
704 sanitize_client(&hi->canon_hostname,
705 ai->ai_canonname);
706 else
707 strbuf_addbuf(&hi->canon_hostname,
708 &hi->ip_address);
710 freeaddrinfo(ai);
712 #else
713 struct hostent *hent;
714 struct sockaddr_in sa;
715 char **ap;
716 static char addrbuf[HOST_NAME_MAX + 1];
718 hent = gethostbyname(hi->hostname.buf);
719 if (hent) {
720 ap = hent->h_addr_list;
721 memset(&sa, 0, sizeof sa);
722 sa.sin_family = hent->h_addrtype;
723 sa.sin_port = htons(0);
724 memcpy(&sa.sin_addr, *ap, hent->h_length);
726 inet_ntop(hent->h_addrtype, &sa.sin_addr,
727 addrbuf, sizeof(addrbuf));
729 sanitize_client(&hi->canon_hostname, hent->h_name);
730 strbuf_addstr(&hi->ip_address, addrbuf);
732 #endif
733 hi->hostname_lookup_done = 1;
737 static void hostinfo_clear(struct hostinfo *hi)
739 strbuf_release(&hi->hostname);
740 strbuf_release(&hi->canon_hostname);
741 strbuf_release(&hi->ip_address);
742 strbuf_release(&hi->tcp_port);
745 static void set_keep_alive(int sockfd)
747 int ka = 1;
749 if (setsockopt(sockfd, SOL_SOCKET, SO_KEEPALIVE, &ka, sizeof(ka)) < 0) {
750 if (errno != ENOTSOCK)
751 logerror("unable to set SO_KEEPALIVE on socket: %s",
752 strerror(errno));
756 static int execute(void)
758 char *line = packet_buffer;
759 int pktlen, len, i;
760 char *addr = getenv("REMOTE_ADDR"), *port = getenv("REMOTE_PORT");
761 struct hostinfo hi = HOSTINFO_INIT;
762 struct strvec env = STRVEC_INIT;
764 if (addr)
765 loginfo("Connection from %s:%s", addr, port);
767 set_keep_alive(0);
768 alarm(init_timeout ? init_timeout : timeout);
769 pktlen = packet_read(0, packet_buffer, sizeof(packet_buffer), 0);
770 alarm(0);
772 len = strlen(line);
773 if (len && line[len-1] == '\n')
774 line[len-1] = 0;
776 /* parse additional args hidden behind a NUL byte */
777 if (len != pktlen)
778 parse_extra_args(&hi, &env, line + len + 1, pktlen - len - 1);
780 for (i = 0; i < ARRAY_SIZE(daemon_service); i++) {
781 struct daemon_service *s = &(daemon_service[i]);
782 const char *arg;
784 if (skip_prefix(line, "git-", &arg) &&
785 skip_prefix(arg, s->name, &arg) &&
786 *arg++ == ' ') {
788 * Note: The directory here is probably context sensitive,
789 * and might depend on the actual service being performed.
791 int rc = run_service(arg, s, &hi, &env);
792 hostinfo_clear(&hi);
793 strvec_clear(&env);
794 return rc;
798 hostinfo_clear(&hi);
799 strvec_clear(&env);
800 logerror("Protocol error: '%s'", line);
801 return -1;
804 static int addrcmp(const struct sockaddr_storage *s1,
805 const struct sockaddr_storage *s2)
807 const struct sockaddr *sa1 = (const struct sockaddr*) s1;
808 const struct sockaddr *sa2 = (const struct sockaddr*) s2;
810 if (sa1->sa_family != sa2->sa_family)
811 return sa1->sa_family - sa2->sa_family;
812 if (sa1->sa_family == AF_INET)
813 return memcmp(&((struct sockaddr_in *)s1)->sin_addr,
814 &((struct sockaddr_in *)s2)->sin_addr,
815 sizeof(struct in_addr));
816 #ifndef NO_IPV6
817 if (sa1->sa_family == AF_INET6)
818 return memcmp(&((struct sockaddr_in6 *)s1)->sin6_addr,
819 &((struct sockaddr_in6 *)s2)->sin6_addr,
820 sizeof(struct in6_addr));
821 #endif
822 return 0;
825 static int max_connections = 32;
827 static unsigned int live_children;
829 static struct child {
830 struct child *next;
831 struct child_process cld;
832 struct sockaddr_storage address;
833 } *firstborn;
835 static void add_child(struct child_process *cld, struct sockaddr *addr, socklen_t addrlen)
837 struct child *newborn, **cradle;
839 CALLOC_ARRAY(newborn, 1);
840 live_children++;
841 memcpy(&newborn->cld, cld, sizeof(*cld));
842 memcpy(&newborn->address, addr, addrlen);
843 for (cradle = &firstborn; *cradle; cradle = &(*cradle)->next)
844 if (!addrcmp(&(*cradle)->address, &newborn->address))
845 break;
846 newborn->next = *cradle;
847 *cradle = newborn;
851 * This gets called if the number of connections grows
852 * past "max_connections".
854 * We kill the newest connection from a duplicate IP.
856 static void kill_some_child(void)
858 const struct child *blanket, *next;
860 if (!(blanket = firstborn))
861 return;
863 for (; (next = blanket->next); blanket = next)
864 if (!addrcmp(&blanket->address, &next->address)) {
865 kill(blanket->cld.pid, SIGTERM);
866 break;
870 static void check_dead_children(void)
872 int status;
873 pid_t pid;
875 struct child **cradle, *blanket;
876 for (cradle = &firstborn; (blanket = *cradle);)
877 if ((pid = waitpid(blanket->cld.pid, &status, WNOHANG)) > 1) {
878 const char *dead = "";
879 if (status)
880 dead = " (with error)";
881 loginfo("[%"PRIuMAX"] Disconnected%s", (uintmax_t)pid, dead);
883 /* remove the child */
884 *cradle = blanket->next;
885 live_children--;
886 child_process_clear(&blanket->cld);
887 free(blanket);
888 } else
889 cradle = &blanket->next;
892 static struct strvec cld_argv = STRVEC_INIT;
893 static void handle(int incoming, struct sockaddr *addr, socklen_t addrlen)
895 struct child_process cld = CHILD_PROCESS_INIT;
897 if (max_connections && live_children >= max_connections) {
898 kill_some_child();
899 sleep(1); /* give it some time to die */
900 check_dead_children();
901 if (live_children >= max_connections) {
902 close(incoming);
903 logerror("Too many children, dropping connection");
904 return;
908 if (addr->sa_family == AF_INET) {
909 char buf[128] = "";
910 struct sockaddr_in *sin_addr = (void *) addr;
911 inet_ntop(addr->sa_family, &sin_addr->sin_addr, buf, sizeof(buf));
912 strvec_pushf(&cld.env, "REMOTE_ADDR=%s", buf);
913 strvec_pushf(&cld.env, "REMOTE_PORT=%d",
914 ntohs(sin_addr->sin_port));
915 #ifndef NO_IPV6
916 } else if (addr->sa_family == AF_INET6) {
917 char buf[128] = "";
918 struct sockaddr_in6 *sin6_addr = (void *) addr;
919 inet_ntop(AF_INET6, &sin6_addr->sin6_addr, buf, sizeof(buf));
920 strvec_pushf(&cld.env, "REMOTE_ADDR=[%s]", buf);
921 strvec_pushf(&cld.env, "REMOTE_PORT=%d",
922 ntohs(sin6_addr->sin6_port));
923 #endif
926 strvec_pushv(&cld.args, cld_argv.v);
927 cld.in = incoming;
928 cld.out = dup(incoming);
930 if (start_command(&cld))
931 logerror("unable to fork");
932 else
933 add_child(&cld, addr, addrlen);
936 static void child_handler(int signo UNUSED)
939 * Otherwise empty handler because systemcalls will get interrupted
940 * upon signal receipt
941 * SysV needs the handler to be rearmed
943 signal(SIGCHLD, child_handler);
946 static int set_reuse_addr(int sockfd)
948 int on = 1;
950 if (!reuseaddr)
951 return 0;
952 return setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR,
953 &on, sizeof(on));
956 struct socketlist {
957 int *list;
958 size_t nr;
959 size_t alloc;
962 static const char *ip2str(int family, struct sockaddr *sin, socklen_t len)
964 #ifdef NO_IPV6
965 static char ip[INET_ADDRSTRLEN];
966 #else
967 static char ip[INET6_ADDRSTRLEN];
968 #endif
970 switch (family) {
971 #ifndef NO_IPV6
972 case AF_INET6:
973 inet_ntop(family, &((struct sockaddr_in6*)sin)->sin6_addr, ip, len);
974 break;
975 #endif
976 case AF_INET:
977 inet_ntop(family, &((struct sockaddr_in*)sin)->sin_addr, ip, len);
978 break;
979 default:
980 xsnprintf(ip, sizeof(ip), "<unknown>");
982 return ip;
985 #ifndef NO_IPV6
987 static int setup_named_sock(char *listen_addr, int listen_port, struct socketlist *socklist)
989 int socknum = 0;
990 char pbuf[NI_MAXSERV];
991 struct addrinfo hints, *ai0, *ai;
992 int gai;
993 long flags;
995 xsnprintf(pbuf, sizeof(pbuf), "%d", listen_port);
996 memset(&hints, 0, sizeof(hints));
997 hints.ai_family = AF_UNSPEC;
998 hints.ai_socktype = SOCK_STREAM;
999 hints.ai_protocol = IPPROTO_TCP;
1000 hints.ai_flags = AI_PASSIVE;
1002 gai = getaddrinfo(listen_addr, pbuf, &hints, &ai0);
1003 if (gai) {
1004 logerror("getaddrinfo() for %s failed: %s", listen_addr, gai_strerror(gai));
1005 return 0;
1008 for (ai = ai0; ai; ai = ai->ai_next) {
1009 int sockfd;
1011 sockfd = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1012 if (sockfd < 0)
1013 continue;
1014 if (sockfd >= FD_SETSIZE) {
1015 logerror("Socket descriptor too large");
1016 close(sockfd);
1017 continue;
1020 #ifdef IPV6_V6ONLY
1021 if (ai->ai_family == AF_INET6) {
1022 int on = 1;
1023 setsockopt(sockfd, IPPROTO_IPV6, IPV6_V6ONLY,
1024 &on, sizeof(on));
1025 /* Note: error is not fatal */
1027 #endif
1029 if (set_reuse_addr(sockfd)) {
1030 logerror("Could not set SO_REUSEADDR: %s", strerror(errno));
1031 close(sockfd);
1032 continue;
1035 set_keep_alive(sockfd);
1037 if (bind(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
1038 logerror("Could not bind to %s: %s",
1039 ip2str(ai->ai_family, ai->ai_addr, ai->ai_addrlen),
1040 strerror(errno));
1041 close(sockfd);
1042 continue; /* not fatal */
1044 if (listen(sockfd, 5) < 0) {
1045 logerror("Could not listen to %s: %s",
1046 ip2str(ai->ai_family, ai->ai_addr, ai->ai_addrlen),
1047 strerror(errno));
1048 close(sockfd);
1049 continue; /* not fatal */
1052 flags = fcntl(sockfd, F_GETFD, 0);
1053 if (flags >= 0)
1054 fcntl(sockfd, F_SETFD, flags | FD_CLOEXEC);
1056 ALLOC_GROW(socklist->list, socklist->nr + 1, socklist->alloc);
1057 socklist->list[socklist->nr++] = sockfd;
1058 socknum++;
1061 freeaddrinfo(ai0);
1063 return socknum;
1066 #else /* NO_IPV6 */
1068 static int setup_named_sock(char *listen_addr, int listen_port, struct socketlist *socklist)
1070 struct sockaddr_in sin;
1071 int sockfd;
1072 long flags;
1074 memset(&sin, 0, sizeof sin);
1075 sin.sin_family = AF_INET;
1076 sin.sin_port = htons(listen_port);
1078 if (listen_addr) {
1079 /* Well, host better be an IP address here. */
1080 if (inet_pton(AF_INET, listen_addr, &sin.sin_addr.s_addr) <= 0)
1081 return 0;
1082 } else {
1083 sin.sin_addr.s_addr = htonl(INADDR_ANY);
1086 sockfd = socket(AF_INET, SOCK_STREAM, 0);
1087 if (sockfd < 0)
1088 return 0;
1090 if (set_reuse_addr(sockfd)) {
1091 logerror("Could not set SO_REUSEADDR: %s", strerror(errno));
1092 close(sockfd);
1093 return 0;
1096 set_keep_alive(sockfd);
1098 if ( bind(sockfd, (struct sockaddr *)&sin, sizeof sin) < 0 ) {
1099 logerror("Could not bind to %s: %s",
1100 ip2str(AF_INET, (struct sockaddr *)&sin, sizeof(sin)),
1101 strerror(errno));
1102 close(sockfd);
1103 return 0;
1106 if (listen(sockfd, 5) < 0) {
1107 logerror("Could not listen to %s: %s",
1108 ip2str(AF_INET, (struct sockaddr *)&sin, sizeof(sin)),
1109 strerror(errno));
1110 close(sockfd);
1111 return 0;
1114 flags = fcntl(sockfd, F_GETFD, 0);
1115 if (flags >= 0)
1116 fcntl(sockfd, F_SETFD, flags | FD_CLOEXEC);
1118 ALLOC_GROW(socklist->list, socklist->nr + 1, socklist->alloc);
1119 socklist->list[socklist->nr++] = sockfd;
1120 return 1;
1123 #endif
1125 static void socksetup(struct string_list *listen_addr, int listen_port, struct socketlist *socklist)
1127 if (!listen_addr->nr)
1128 setup_named_sock(NULL, listen_port, socklist);
1129 else {
1130 int i, socknum;
1131 for (i = 0; i < listen_addr->nr; i++) {
1132 socknum = setup_named_sock(listen_addr->items[i].string,
1133 listen_port, socklist);
1135 if (socknum == 0)
1136 logerror("unable to allocate any listen sockets for host %s on port %u",
1137 listen_addr->items[i].string, listen_port);
1142 static int service_loop(struct socketlist *socklist)
1144 struct pollfd *pfd;
1145 int i;
1147 CALLOC_ARRAY(pfd, socklist->nr);
1149 for (i = 0; i < socklist->nr; i++) {
1150 pfd[i].fd = socklist->list[i];
1151 pfd[i].events = POLLIN;
1154 signal(SIGCHLD, child_handler);
1156 for (;;) {
1157 int i;
1159 check_dead_children();
1161 if (poll(pfd, socklist->nr, -1) < 0) {
1162 if (errno != EINTR) {
1163 logerror("Poll failed, resuming: %s",
1164 strerror(errno));
1165 sleep(1);
1167 continue;
1170 for (i = 0; i < socklist->nr; i++) {
1171 if (pfd[i].revents & POLLIN) {
1172 union {
1173 struct sockaddr sa;
1174 struct sockaddr_in sai;
1175 #ifndef NO_IPV6
1176 struct sockaddr_in6 sai6;
1177 #endif
1178 } ss;
1179 socklen_t sslen = sizeof(ss);
1180 int incoming = accept(pfd[i].fd, &ss.sa, &sslen);
1181 if (incoming < 0) {
1182 switch (errno) {
1183 case EAGAIN:
1184 case EINTR:
1185 case ECONNABORTED:
1186 continue;
1187 default:
1188 die_errno("accept returned");
1191 handle(incoming, &ss.sa, sslen);
1197 #ifdef NO_POSIX_GOODIES
1199 struct credentials;
1201 static void drop_privileges(struct credentials *cred)
1203 /* nothing */
1206 static struct credentials *prepare_credentials(const char *user_name,
1207 const char *group_name)
1209 die("--user not supported on this platform");
1212 #else
1214 struct credentials {
1215 struct passwd *pass;
1216 gid_t gid;
1219 static void drop_privileges(struct credentials *cred)
1221 if (cred && (initgroups(cred->pass->pw_name, cred->gid) ||
1222 setgid (cred->gid) || setuid(cred->pass->pw_uid)))
1223 die("cannot drop privileges");
1226 static struct credentials *prepare_credentials(const char *user_name,
1227 const char *group_name)
1229 static struct credentials c;
1231 c.pass = getpwnam(user_name);
1232 if (!c.pass)
1233 die("user not found - %s", user_name);
1235 if (!group_name)
1236 c.gid = c.pass->pw_gid;
1237 else {
1238 struct group *group = getgrnam(group_name);
1239 if (!group)
1240 die("group not found - %s", group_name);
1242 c.gid = group->gr_gid;
1245 return &c;
1247 #endif
1249 static int serve(struct string_list *listen_addr, int listen_port,
1250 struct credentials *cred)
1252 struct socketlist socklist = { NULL, 0, 0 };
1254 socksetup(listen_addr, listen_port, &socklist);
1255 if (socklist.nr == 0)
1256 die("unable to allocate any listen sockets on port %u",
1257 listen_port);
1259 drop_privileges(cred);
1261 loginfo("Ready to rumble");
1263 return service_loop(&socklist);
1266 int cmd_main(int argc, const char **argv)
1268 int listen_port = 0;
1269 struct string_list listen_addr = STRING_LIST_INIT_NODUP;
1270 int serve_mode = 0, inetd_mode = 0;
1271 const char *pid_file = NULL, *user_name = NULL, *group_name = NULL;
1272 int detach = 0;
1273 struct credentials *cred = NULL;
1274 int i;
1276 for (i = 1; i < argc; i++) {
1277 const char *arg = argv[i];
1278 const char *v;
1280 if (skip_prefix(arg, "--listen=", &v)) {
1281 string_list_append(&listen_addr, xstrdup_tolower(v));
1282 continue;
1284 if (skip_prefix(arg, "--port=", &v)) {
1285 char *end;
1286 unsigned long n;
1287 n = strtoul(v, &end, 0);
1288 if (*v && !*end) {
1289 listen_port = n;
1290 continue;
1293 if (!strcmp(arg, "--serve")) {
1294 serve_mode = 1;
1295 continue;
1297 if (!strcmp(arg, "--inetd")) {
1298 inetd_mode = 1;
1299 continue;
1301 if (!strcmp(arg, "--verbose")) {
1302 verbose = 1;
1303 continue;
1305 if (!strcmp(arg, "--syslog")) {
1306 log_destination = LOG_DESTINATION_SYSLOG;
1307 continue;
1309 if (skip_prefix(arg, "--log-destination=", &v)) {
1310 if (!strcmp(v, "syslog")) {
1311 log_destination = LOG_DESTINATION_SYSLOG;
1312 continue;
1313 } else if (!strcmp(v, "stderr")) {
1314 log_destination = LOG_DESTINATION_STDERR;
1315 continue;
1316 } else if (!strcmp(v, "none")) {
1317 log_destination = LOG_DESTINATION_NONE;
1318 continue;
1319 } else
1320 die("unknown log destination '%s'", v);
1322 if (!strcmp(arg, "--export-all")) {
1323 export_all_trees = 1;
1324 continue;
1326 if (skip_prefix(arg, "--access-hook=", &v)) {
1327 access_hook = v;
1328 continue;
1330 if (skip_prefix(arg, "--timeout=", &v)) {
1331 timeout = atoi(v);
1332 continue;
1334 if (skip_prefix(arg, "--init-timeout=", &v)) {
1335 init_timeout = atoi(v);
1336 continue;
1338 if (skip_prefix(arg, "--max-connections=", &v)) {
1339 max_connections = atoi(v);
1340 if (max_connections < 0)
1341 max_connections = 0; /* unlimited */
1342 continue;
1344 if (!strcmp(arg, "--strict-paths")) {
1345 strict_paths = 1;
1346 continue;
1348 if (skip_prefix(arg, "--base-path=", &v)) {
1349 base_path = v;
1350 continue;
1352 if (!strcmp(arg, "--base-path-relaxed")) {
1353 base_path_relaxed = 1;
1354 continue;
1356 if (skip_prefix(arg, "--interpolated-path=", &v)) {
1357 interpolated_path = v;
1358 continue;
1360 if (!strcmp(arg, "--reuseaddr")) {
1361 reuseaddr = 1;
1362 continue;
1364 if (!strcmp(arg, "--user-path")) {
1365 user_path = "";
1366 continue;
1368 if (skip_prefix(arg, "--user-path=", &v)) {
1369 user_path = v;
1370 continue;
1372 if (skip_prefix(arg, "--pid-file=", &v)) {
1373 pid_file = v;
1374 continue;
1376 if (!strcmp(arg, "--detach")) {
1377 detach = 1;
1378 continue;
1380 if (skip_prefix(arg, "--user=", &v)) {
1381 user_name = v;
1382 continue;
1384 if (skip_prefix(arg, "--group=", &v)) {
1385 group_name = v;
1386 continue;
1388 if (skip_prefix(arg, "--enable=", &v)) {
1389 enable_service(v, 1);
1390 continue;
1392 if (skip_prefix(arg, "--disable=", &v)) {
1393 enable_service(v, 0);
1394 continue;
1396 if (skip_prefix(arg, "--allow-override=", &v)) {
1397 make_service_overridable(v, 1);
1398 continue;
1400 if (skip_prefix(arg, "--forbid-override=", &v)) {
1401 make_service_overridable(v, 0);
1402 continue;
1404 if (!strcmp(arg, "--informative-errors")) {
1405 informative_errors = 1;
1406 continue;
1408 if (!strcmp(arg, "--no-informative-errors")) {
1409 informative_errors = 0;
1410 continue;
1412 if (!strcmp(arg, "--")) {
1413 ok_paths = &argv[i+1];
1414 break;
1415 } else if (arg[0] != '-') {
1416 ok_paths = &argv[i];
1417 break;
1420 usage(daemon_usage);
1423 if (log_destination == LOG_DESTINATION_UNSET) {
1424 if (inetd_mode || detach)
1425 log_destination = LOG_DESTINATION_SYSLOG;
1426 else
1427 log_destination = LOG_DESTINATION_STDERR;
1430 if (log_destination == LOG_DESTINATION_SYSLOG) {
1431 openlog("git-daemon", LOG_PID, LOG_DAEMON);
1432 set_die_routine(daemon_die);
1433 } else
1434 /* avoid splitting a message in the middle */
1435 setvbuf(stderr, NULL, _IOFBF, 4096);
1437 if (inetd_mode && (detach || group_name || user_name))
1438 die("--detach, --user and --group are incompatible with --inetd");
1440 if (inetd_mode && (listen_port || (listen_addr.nr > 0)))
1441 die("--listen= and --port= are incompatible with --inetd");
1442 else if (listen_port == 0)
1443 listen_port = DEFAULT_GIT_PORT;
1445 if (group_name && !user_name)
1446 die("--group supplied without --user");
1448 if (user_name)
1449 cred = prepare_credentials(user_name, group_name);
1451 if (strict_paths && (!ok_paths || !*ok_paths))
1452 die("option --strict-paths requires '<directory>' arguments");
1454 if (base_path && !is_directory(base_path))
1455 die("base-path '%s' does not exist or is not a directory",
1456 base_path);
1458 if (log_destination != LOG_DESTINATION_STDERR) {
1459 if (!freopen("/dev/null", "w", stderr))
1460 die_errno("failed to redirect stderr to /dev/null");
1463 if (inetd_mode || serve_mode)
1464 return execute();
1466 if (detach) {
1467 if (daemonize())
1468 die("--detach not supported on this platform");
1471 if (pid_file)
1472 write_file(pid_file, "%"PRIuMAX, (uintmax_t) getpid());
1474 /* prepare argv for serving-processes */
1475 strvec_push(&cld_argv, argv[0]); /* git-daemon */
1476 strvec_push(&cld_argv, "--serve");
1477 for (i = 1; i < argc; ++i)
1478 strvec_push(&cld_argv, argv[i]);
1480 return serve(&listen_addr, listen_port, cred);