1#include "cache.h"
2#include "pkt-line.h"
3#include "exec_cmd.h"
4#include <syslog.h>
6#ifndef HOST_NAME_MAX
8#define HOST_NAME_MAX 256
9#endif
10#ifndef NI_MAXSERV
12#define NI_MAXSERV 32
13#endif
14static int log_syslog;
16static int verbose;
17static int reuseaddr;
18static const char daemon_usage[] =
20"git daemon [--verbose] [--syslog] [--export-all]\n"
21" [--timeout=n] [--init-timeout=n] [--max-connections=n]\n"
22" [--strict-paths] [--base-path=path] [--base-path-relaxed]\n"
23" [--user-path | --user-path=path]\n"
24" [--interpolated-path=path]\n"
25" [--reuseaddr] [--detach] [--pid-file=file]\n"
26" [--[enable|disable|allow-override|forbid-override]=service]\n"
27" [--inetd | [--listen=host_or_ipaddr] [--port=n]\n"
28" [--user=user [--group=group]]\n"
29" [directory...]";
30/* List of acceptable pathname prefixes */
32static char **ok_paths;
33static int strict_paths;
34/* If this is set, git-daemon-export-ok is not required */
36static int export_all_trees;
37/* Take all paths relative to this one if non-NULL */
39static char *base_path;
40static char *interpolated_path;
41static int base_path_relaxed;
42/* Flag indicating client sent extra args. */
44static int saw_extended_args;
45/* If defined, ~user notation is allowed and the string is inserted
47 * after ~user/. E.g. a request to git://host/~alice/frotz would
48 * go to /home/alice/pub_git/frotz with --user-path=pub_git.
49 */
50static const char *user_path;
51/* Timeout, and initial timeout */
53static unsigned int timeout;
54static unsigned int init_timeout;
55static char *hostname;
57static char *canon_hostname;
58static char *ip_address;
59static char *tcp_port;
60static void logreport(int priority, const char *err, va_list params)
62{
63 if (log_syslog) {
64 char buf[1024];
65 vsnprintf(buf, sizeof(buf), err, params);
66 syslog(priority, "%s", buf);
67 } else {
68 /*
69 * Since stderr is set to linebuffered mode, the
70 * logging of different processes will not overlap
71 */
72 fprintf(stderr, "[%"PRIuMAX"] ", (uintmax_t)getpid());
73 vfprintf(stderr, err, params);
74 fputc('\n', stderr);
75 }
76}
77static void logerror(const char *err, ...)
79{
80 va_list params;
81 va_start(params, err);
82 logreport(LOG_ERR, err, params);
83 va_end(params);
84}
85static void loginfo(const char *err, ...)
87{
88 va_list params;
89 if (!verbose)
90 return;
91 va_start(params, err);
92 logreport(LOG_INFO, err, params);
93 va_end(params);
94}
95static void NORETURN daemon_die(const char *err, va_list params)
97{
98 logreport(LOG_ERR, err, params);
99 exit(1);
100}
101static int avoid_alias(char *p)
103{
104 int sl, ndot;
105 /*
107 * This resurrects the belts and suspenders paranoia check by HPA
108 * done in <435560F7.4080006@zytor.com> thread, now enter_repo()
109 * does not do getcwd() based path canonicalizations.
110 *
111 * sl becomes true immediately after seeing '/' and continues to
112 * be true as long as dots continue after that without intervening
113 * non-dot character.
114 */
115 if (!p || (*p != '/' && *p != '~'))
116 return -1;
117 sl = 1; ndot = 0;
118 p++;
119 while (1) {
121 char ch = *p++;
122 if (sl) {
123 if (ch == '.')
124 ndot++;
125 else if (ch == '/') {
126 if (ndot < 3)
127 /* reject //, /./ and /../ */
128 return -1;
129 ndot = 0;
130 }
131 else if (ch == 0) {
132 if (0 < ndot && ndot < 3)
133 /* reject /.$ and /..$ */
134 return -1;
135 return 0;
136 }
137 else
138 sl = ndot = 0;
139 }
140 else if (ch == 0)
141 return 0;
142 else if (ch == '/') {
143 sl = 1;
144 ndot = 0;
145 }
146 }
147}
148static char *path_ok(char *directory)
150{
151 static char rpath[PATH_MAX];
152 static char interp_path[PATH_MAX];
153 char *path;
154 char *dir;
155 dir = directory;
157 if (avoid_alias(dir)) {
159 logerror("'%s': aliased", dir);
160 return NULL;
161 }
162 if (*dir == '~') {
164 if (!user_path) {
165 logerror("'%s': User-path not allowed", dir);
166 return NULL;
167 }
168 if (*user_path) {
169 /* Got either "~alice" or "~alice/foo";
170 * rewrite them to "~alice/%s" or
171 * "~alice/%s/foo".
172 */
173 int namlen, restlen = strlen(dir);
174 char *slash = strchr(dir, '/');
175 if (!slash)
176 slash = dir + restlen;
177 namlen = slash - dir;
178 restlen -= namlen;
179 loginfo("userpath <%s>, request <%s>, namlen %d, restlen %d, slash <%s>", user_path, dir, namlen, restlen, slash);
180 snprintf(rpath, PATH_MAX, "%.*s/%s%.*s",
181 namlen, dir, user_path, restlen, slash);
182 dir = rpath;
183 }
184 }
185 else if (interpolated_path && saw_extended_args) {
186 struct strbuf expanded_path = STRBUF_INIT;
187 struct strbuf_expand_dict_entry dict[] = {
188 { "H", hostname },
189 { "CH", canon_hostname },
190 { "IP", ip_address },
191 { "P", tcp_port },
192 { "D", directory },
193 { "%", "%" },
194 { NULL }
195 };
196 if (*dir != '/') {
198 /* Allow only absolute */
199 logerror("'%s': Non-absolute path denied (interpolated-path active)", dir);
200 return NULL;
201 }
202 strbuf_expand(&expanded_path, interpolated_path,
204 strbuf_expand_dict_cb, &dict);
205 strlcpy(interp_path, expanded_path.buf, PATH_MAX);
206 strbuf_release(&expanded_path);
207 loginfo("Interpolated dir '%s'", interp_path);
208 dir = interp_path;
210 }
211 else if (base_path) {
212 if (*dir != '/') {
213 /* Allow only absolute */
214 logerror("'%s': Non-absolute path denied (base-path active)", dir);
215 return NULL;
216 }
217 snprintf(rpath, PATH_MAX, "%s%s", base_path, dir);
218 dir = rpath;
219 }
220 path = enter_repo(dir, strict_paths);
222 if (!path && base_path && base_path_relaxed) {
223 /*
224 * if we fail and base_path_relaxed is enabled, try without
225 * prefixing the base path
226 */
227 dir = directory;
228 path = enter_repo(dir, strict_paths);
229 }
230 if (!path) {
232 logerror("'%s' does not appear to be a git repository", dir);
233 return NULL;
234 }
235 if ( ok_paths && *ok_paths ) {
237 char **pp;
238 int pathlen = strlen(path);
239 /* The validation is done on the paths after enter_repo
241 * appends optional {.git,.git/.git} and friends, but
242 * it does not use getcwd(). So if your /pub is
243 * a symlink to /mnt/pub, you can whitelist /pub and
244 * do not have to say /mnt/pub.
245 * Do not say /pub/.
246 */
247 for ( pp = ok_paths ; *pp ; pp++ ) {
248 int len = strlen(*pp);
249 if (len <= pathlen &&
250 !memcmp(*pp, path, len) &&
251 (path[len] == '\0' ||
252 (!strict_paths && path[len] == '/')))
253 return path;
254 }
255 }
256 else {
257 /* be backwards compatible */
258 if (!strict_paths)
259 return path;
260 }
261 logerror("'%s': not in whitelist", path);
263 return NULL; /* Fallthrough. Deny by default */
264}
265typedef int (*daemon_service_fn)(void);
267struct daemon_service {
268 const char *name;
269 const char *config_name;
270 daemon_service_fn fn;
271 int enabled;
272 int overridable;
273};
274static struct daemon_service *service_looking_at;
276static int service_enabled;
277static int git_daemon_config(const char *var, const char *value, void *cb)
279{
280 if (!prefixcmp(var, "daemon.") &&
281 !strcmp(var + 7, service_looking_at->config_name)) {
282 service_enabled = git_config_bool(var, value);
283 return 0;
284 }
285 /* we are not interested in parsing any other configuration here */
287 return 0;
288}
289static int run_service(char *dir, struct daemon_service *service)
291{
292 const char *path;
293 int enabled = service->enabled;
294 loginfo("Request %s for '%s'", service->name, dir);
296 if (!enabled && !service->overridable) {
298 logerror("'%s': service not enabled.", service->name);
299 errno = EACCES;
300 return -1;
301 }
302 if (!(path = path_ok(dir)))
304 return -1;
305 /*
307 * Security on the cheap.
308 *
309 * We want a readable HEAD, usable "objects" directory, and
310 * a "git-daemon-export-ok" flag that says that the other side
311 * is ok with us doing this.
312 *
313 * path_ok() uses enter_repo() and does whitelist checking.
314 * We only need to make sure the repository is exported.
315 */
316 if (!export_all_trees && access("git-daemon-export-ok", F_OK)) {
318 logerror("'%s': repository not exported.", path);
319 errno = EACCES;
320 return -1;
321 }
322 if (service->overridable) {
324 service_looking_at = service;
325 service_enabled = -1;
326 git_config(git_daemon_config, NULL);
327 if (0 <= service_enabled)
328 enabled = service_enabled;
329 }
330 if (!enabled) {
331 logerror("'%s': service not enabled for '%s'",
332 service->name, path);
333 errno = EACCES;
334 return -1;
335 }
336 /*
338 * We'll ignore SIGTERM from now on, we have a
339 * good client.
340 */
341 signal(SIGTERM, SIG_IGN);
342 return service->fn();
344}
345static int upload_pack(void)
347{
348 /* Timeout as string */
349 char timeout_buf[64];
350 snprintf(timeout_buf, sizeof timeout_buf, "--timeout=%u", timeout);
352 /* git-upload-pack only ever reads stuff, so this is safe */
354 execl_git_cmd("upload-pack", "--strict", timeout_buf, ".", NULL);
355 return -1;
356}
357static int upload_archive(void)
359{
360 execl_git_cmd("upload-archive", ".", NULL);
361 return -1;
362}
363static int receive_pack(void)
365{
366 execl_git_cmd("receive-pack", ".", NULL);
367 return -1;
368}
369static struct daemon_service daemon_service[] = {
371 { "upload-archive", "uploadarch", upload_archive, 0, 1 },
372 { "upload-pack", "uploadpack", upload_pack, 1, 1 },
373 { "receive-pack", "receivepack", receive_pack, 0, 1 },
374};
375static void enable_service(const char *name, int ena)
377{
378 int i;
379 for (i = 0; i < ARRAY_SIZE(daemon_service); i++) {
380 if (!strcmp(daemon_service[i].name, name)) {
381 daemon_service[i].enabled = ena;
382 return;
383 }
384 }
385 die("No such service %s", name);
386}
387static void make_service_overridable(const char *name, int ena)
389{
390 int i;
391 for (i = 0; i < ARRAY_SIZE(daemon_service); i++) {
392 if (!strcmp(daemon_service[i].name, name)) {
393 daemon_service[i].overridable = ena;
394 return;
395 }
396 }
397 die("No such service %s", name);
398}
399static char *xstrdup_tolower(const char *str)
401{
402 char *p, *dup = xstrdup(str);
403 for (p = dup; *p; p++)
404 *p = tolower(*p);
405 return dup;
406}
407/*
409 * Read the host as supplied by the client connection.
410 */
411static void parse_host_arg(char *extra_args, int buflen)
412{
413 char *val;
414 int vallen;
415 char *end = extra_args + buflen;
416 if (extra_args < end && *extra_args) {
418 saw_extended_args = 1;
419 if (strncasecmp("host=", extra_args, 5) == 0) {
420 val = extra_args + 5;
421 vallen = strlen(val) + 1;
422 if (*val) {
423 /* Split <host>:<port> at colon. */
424 char *host = val;
425 char *port = strrchr(host, ':');
426 if (port) {
427 *port = 0;
428 port++;
429 free(tcp_port);
430 tcp_port = xstrdup(port);
431 }
432 free(hostname);
433 hostname = xstrdup_tolower(host);
434 }
435 /* On to the next one */
437 extra_args = val + vallen;
438 }
439 if (extra_args < end && *extra_args)
440 die("Invalid request");
441 }
442 /*
444 * Locate canonical hostname and its IP address.
445 */
446 if (hostname) {
447#ifndef NO_IPV6
448 struct addrinfo hints;
449 struct addrinfo *ai;
450 int gai;
451 static char addrbuf[HOST_NAME_MAX + 1];
452 memset(&hints, 0, sizeof(hints));
454 hints.ai_flags = AI_CANONNAME;
455 gai = getaddrinfo(hostname, 0, &hints, &ai);
457 if (!gai) {
458 struct sockaddr_in *sin_addr = (void *)ai->ai_addr;
459 inet_ntop(AF_INET, &sin_addr->sin_addr,
461 addrbuf, sizeof(addrbuf));
462 free(ip_address);
463 ip_address = xstrdup(addrbuf);
464 free(canon_hostname);
466 canon_hostname = xstrdup(ai->ai_canonname ?
467 ai->ai_canonname : ip_address);
468 freeaddrinfo(ai);
470 }
471#else
472 struct hostent *hent;
473 struct sockaddr_in sa;
474 char **ap;
475 static char addrbuf[HOST_NAME_MAX + 1];
476 hent = gethostbyname(hostname);
478 ap = hent->h_addr_list;
480 memset(&sa, 0, sizeof sa);
481 sa.sin_family = hent->h_addrtype;
482 sa.sin_port = htons(0);
483 memcpy(&sa.sin_addr, *ap, hent->h_length);
484 inet_ntop(hent->h_addrtype, &sa.sin_addr,
486 addrbuf, sizeof(addrbuf));
487 free(canon_hostname);
489 canon_hostname = xstrdup(hent->h_name);
490 free(ip_address);
491 ip_address = xstrdup(addrbuf);
492#endif
493 }
494}
495static int execute(struct sockaddr *addr)
498{
499 static char line[1000];
500 int pktlen, len, i;
501 if (addr) {
503 char addrbuf[256] = "";
504 int port = -1;
505 if (addr->sa_family == AF_INET) {
507 struct sockaddr_in *sin_addr = (void *) addr;
508 inet_ntop(addr->sa_family, &sin_addr->sin_addr, addrbuf, sizeof(addrbuf));
509 port = ntohs(sin_addr->sin_port);
510#ifndef NO_IPV6
511 } else if (addr && addr->sa_family == AF_INET6) {
512 struct sockaddr_in6 *sin6_addr = (void *) addr;
513 char *buf = addrbuf;
515 *buf++ = '['; *buf = '\0'; /* stpcpy() is cool */
516 inet_ntop(AF_INET6, &sin6_addr->sin6_addr, buf, sizeof(addrbuf) - 1);
517 strcat(buf, "]");
518 port = ntohs(sin6_addr->sin6_port);
520#endif
521 }
522 loginfo("Connection from %s:%d", addrbuf, port);
523 setenv("REMOTE_ADDR", addrbuf, 1);
524 }
525 else {
526 unsetenv("REMOTE_ADDR");
527 }
528 alarm(init_timeout ? init_timeout : timeout);
530 pktlen = packet_read_line(0, line, sizeof(line));
531 alarm(0);
532 len = strlen(line);
534 if (pktlen != len)
535 loginfo("Extended attributes (%d bytes) exist <%.*s>",
536 (int) pktlen - len,
537 (int) pktlen - len, line + len + 1);
538 if (len && line[len-1] == '\n') {
539 line[--len] = 0;
540 pktlen--;
541 }
542 free(hostname);
544 free(canon_hostname);
545 free(ip_address);
546 free(tcp_port);
547 hostname = canon_hostname = ip_address = tcp_port = NULL;
548 if (len != pktlen)
550 parse_host_arg(line + len + 1, pktlen - len - 1);
551 for (i = 0; i < ARRAY_SIZE(daemon_service); i++) {
553 struct daemon_service *s = &(daemon_service[i]);
554 int namelen = strlen(s->name);
555 if (!prefixcmp(line, "git-") &&
556 !strncmp(s->name, line + 4, namelen) &&
557 line[namelen + 4] == ' ') {
558 /*
559 * Note: The directory here is probably context sensitive,
560 * and might depend on the actual service being performed.
561 */
562 return run_service(line + namelen + 5, s);
563 }
564 }
565 logerror("Protocol error: '%s'", line);
567 return -1;
568}
569static int max_connections = 32;
571static unsigned int live_children;
573static struct child {
575 struct child *next;
576 pid_t pid;
577 struct sockaddr_storage address;
578} *firstborn;
579static void add_child(pid_t pid, struct sockaddr *addr, int addrlen)
581{
582 struct child *newborn, **cradle;
583 /*
585 * This must be xcalloc() -- we'll compare the whole sockaddr_storage
586 * but individual address may be shorter.
587 */
588 newborn = xcalloc(1, sizeof(*newborn));
589 live_children++;
590 newborn->pid = pid;
591 memcpy(&newborn->address, addr, addrlen);
592 for (cradle = &firstborn; *cradle; cradle = &(*cradle)->next)
593 if (!memcmp(&(*cradle)->address, &newborn->address,
594 sizeof(newborn->address)))
595 break;
596 newborn->next = *cradle;
597 *cradle = newborn;
598}
599static void remove_child(pid_t pid)
601{
602 struct child **cradle, *blanket;
603 for (cradle = &firstborn; (blanket = *cradle); cradle = &blanket->next)
605 if (blanket->pid == pid) {
606 *cradle = blanket->next;
607 live_children--;
608 free(blanket);
609 break;
610 }
611}
612/*
614 * This gets called if the number of connections grows
615 * past "max_connections".
616 *
617 * We kill the newest connection from a duplicate IP.
618 */
619static void kill_some_child(void)
620{
621 const struct child *blanket, *next;
622 if (!(blanket = firstborn))
624 return;
625 for (; (next = blanket->next); blanket = next)
627 if (!memcmp(&blanket->address, &next->address,
628 sizeof(next->address))) {
629 kill(blanket->pid, SIGTERM);
630 break;
631 }
632}
633static void check_dead_children(void)
635{
636 int status;
637 pid_t pid;
638 while ((pid = waitpid(-1, &status, WNOHANG)) > 0) {
640 const char *dead = "";
641 remove_child(pid);
642 if (!WIFEXITED(status) || (WEXITSTATUS(status) > 0))
643 dead = " (with error)";
644 loginfo("[%"PRIuMAX"] Disconnected%s", (uintmax_t)pid, dead);
645 }
646}
647static void handle(int incoming, struct sockaddr *addr, int addrlen)
649{
650 pid_t pid;
651 if (max_connections && live_children >= max_connections) {
653 kill_some_child();
654 sleep(1); /* give it some time to die */
655 check_dead_children();
656 if (live_children >= max_connections) {
657 close(incoming);
658 logerror("Too many children, dropping connection");
659 return;
660 }
661 }
662 if ((pid = fork())) {
664 close(incoming);
665 if (pid < 0) {
666 logerror("Couldn't fork %s", strerror(errno));
667 return;
668 }
669 add_child(pid, addr, addrlen);
671 return;
672 }
673 dup2(incoming, 0);
675 dup2(incoming, 1);
676 close(incoming);
677 exit(execute(addr));
679}
680static void child_handler(int signo)
682{
683 /*
684 * Otherwise empty handler because systemcalls will get interrupted
685 * upon signal receipt
686 * SysV needs the handler to be rearmed
687 */
688 signal(SIGCHLD, child_handler);
689}
690static int set_reuse_addr(int sockfd)
692{
693 int on = 1;
694 if (!reuseaddr)
696 return 0;
697 return setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR,
698 &on, sizeof(on));
699}
700#ifndef NO_IPV6
702static int socksetup(char *listen_addr, int listen_port, int **socklist_p)
704{
705 int socknum = 0, *socklist = NULL;
706 int maxfd = -1;
707 char pbuf[NI_MAXSERV];
708 struct addrinfo hints, *ai0, *ai;
709 int gai;
710 long flags;
711 sprintf(pbuf, "%d", listen_port);
713 memset(&hints, 0, sizeof(hints));
714 hints.ai_family = AF_UNSPEC;
715 hints.ai_socktype = SOCK_STREAM;
716 hints.ai_protocol = IPPROTO_TCP;
717 hints.ai_flags = AI_PASSIVE;
718 gai = getaddrinfo(listen_addr, pbuf, &hints, &ai0);
720 if (gai)
721 die("getaddrinfo() failed: %s", gai_strerror(gai));
722 for (ai = ai0; ai; ai = ai->ai_next) {
724 int sockfd;
725 sockfd = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
727 if (sockfd < 0)
728 continue;
729 if (sockfd >= FD_SETSIZE) {
730 logerror("Socket descriptor too large");
731 close(sockfd);
732 continue;
733 }
734#ifdef IPV6_V6ONLY
736 if (ai->ai_family == AF_INET6) {
737 int on = 1;
738 setsockopt(sockfd, IPPROTO_IPV6, IPV6_V6ONLY,
739 &on, sizeof(on));
740 /* Note: error is not fatal */
741 }
742#endif
743 if (set_reuse_addr(sockfd)) {
745 close(sockfd);
746 continue;
747 }
748 if (bind(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
750 close(sockfd);
751 continue; /* not fatal */
752 }
753 if (listen(sockfd, 5) < 0) {
754 close(sockfd);
755 continue; /* not fatal */
756 }
757 flags = fcntl(sockfd, F_GETFD, 0);
759 if (flags >= 0)
760 fcntl(sockfd, F_SETFD, flags | FD_CLOEXEC);
761 socklist = xrealloc(socklist, sizeof(int) * (socknum + 1));
763 socklist[socknum++] = sockfd;
764 if (maxfd < sockfd)
766 maxfd = sockfd;
767 }
768 freeaddrinfo(ai0);
770 *socklist_p = socklist;
772 return socknum;
773}
774#else /* NO_IPV6 */
776static int socksetup(char *listen_addr, int listen_port, int **socklist_p)
778{
779 struct sockaddr_in sin;
780 int sockfd;
781 long flags;
782 memset(&sin, 0, sizeof sin);
784 sin.sin_family = AF_INET;
785 sin.sin_port = htons(listen_port);
786 if (listen_addr) {
788 /* Well, host better be an IP address here. */
789 if (inet_pton(AF_INET, listen_addr, &sin.sin_addr.s_addr) <= 0)
790 return 0;
791 } else {
792 sin.sin_addr.s_addr = htonl(INADDR_ANY);
793 }
794 sockfd = socket(AF_INET, SOCK_STREAM, 0);
796 if (sockfd < 0)
797 return 0;
798 if (set_reuse_addr(sockfd)) {
800 close(sockfd);
801 return 0;
802 }
803 if ( bind(sockfd, (struct sockaddr *)&sin, sizeof sin) < 0 ) {
805 close(sockfd);
806 return 0;
807 }
808 if (listen(sockfd, 5) < 0) {
810 close(sockfd);
811 return 0;
812 }
813 flags = fcntl(sockfd, F_GETFD, 0);
815 if (flags >= 0)
816 fcntl(sockfd, F_SETFD, flags | FD_CLOEXEC);
817 *socklist_p = xmalloc(sizeof(int));
819 **socklist_p = sockfd;
820 return 1;
821}
822#endif
824static int service_loop(int socknum, int *socklist)
826{
827 struct pollfd *pfd;
828 int i;
829 pfd = xcalloc(socknum, sizeof(struct pollfd));
831 for (i = 0; i < socknum; i++) {
833 pfd[i].fd = socklist[i];
834 pfd[i].events = POLLIN;
835 }
836 signal(SIGCHLD, child_handler);
838 for (;;) {
840 int i;
841 check_dead_children();
843 if (poll(pfd, socknum, -1) < 0) {
845 if (errno != EINTR) {
846 logerror("Poll failed, resuming: %s",
847 strerror(errno));
848 sleep(1);
849 }
850 continue;
851 }
852 for (i = 0; i < socknum; i++) {
854 if (pfd[i].revents & POLLIN) {
855 struct sockaddr_storage ss;
856 unsigned int sslen = sizeof(ss);
857 int incoming = accept(pfd[i].fd, (struct sockaddr *)&ss, &sslen);
858 if (incoming < 0) {
859 switch (errno) {
860 case EAGAIN:
861 case EINTR:
862 case ECONNABORTED:
863 continue;
864 default:
865 die("accept returned %s", strerror(errno));
866 }
867 }
868 handle(incoming, (struct sockaddr *)&ss, sslen);
869 }
870 }
871 }
872}
873/* if any standard file descriptor is missing open it to /dev/null */
875static void sanitize_stdfds(void)
876{
877 int fd = open("/dev/null", O_RDWR, 0);
878 while (fd != -1 && fd < 2)
879 fd = dup(fd);
880 if (fd == -1)
881 die("open /dev/null or dup failed: %s", strerror(errno));
882 if (fd > 2)
883 close(fd);
884}
885static void daemonize(void)
887{
888 switch (fork()) {
889 case 0:
890 break;
891 case -1:
892 die("fork failed: %s", strerror(errno));
893 default:
894 exit(0);
895 }
896 if (setsid() == -1)
897 die("setsid failed: %s", strerror(errno));
898 close(0);
899 close(1);
900 close(2);
901 sanitize_stdfds();
902}
903static void store_pid(const char *path)
905{
906 FILE *f = fopen(path, "w");
907 if (!f)
908 die("cannot open pid file %s: %s", path, strerror(errno));
909 if (fprintf(f, "%"PRIuMAX"\n", (uintmax_t) getpid()) < 0 || fclose(f) != 0)
910 die("failed to write pid file %s: %s", path, strerror(errno));
911}
912static int serve(char *listen_addr, int listen_port, struct passwd *pass, gid_t gid)
914{
915 int socknum, *socklist;
916 socknum = socksetup(listen_addr, listen_port, &socklist);
918 if (socknum == 0)
919 die("unable to allocate any listen sockets on host %s port %u",
920 listen_addr, listen_port);
921 if (pass && gid &&
923 (initgroups(pass->pw_name, gid) || setgid (gid) ||
924 setuid(pass->pw_uid)))
925 die("cannot drop privileges");
926 return service_loop(socknum, socklist);
928}
929int main(int argc, char **argv)
931{
932 int listen_port = 0;
933 char *listen_addr = NULL;
934 int inetd_mode = 0;
935 const char *pid_file = NULL, *user_name = NULL, *group_name = NULL;
936 int detach = 0;
937 struct passwd *pass = NULL;
938 struct group *group;
939 gid_t gid = 0;
940 int i;
941 git_extract_argv0_path(argv[0]);
943 for (i = 1; i < argc; i++) {
945 char *arg = argv[i];
946 if (!prefixcmp(arg, "--listen=")) {
948 listen_addr = xstrdup_tolower(arg + 9);
949 continue;
950 }
951 if (!prefixcmp(arg, "--port=")) {
952 char *end;
953 unsigned long n;
954 n = strtoul(arg+7, &end, 0);
955 if (arg[7] && !*end) {
956 listen_port = n;
957 continue;
958 }
959 }
960 if (!strcmp(arg, "--inetd")) {
961 inetd_mode = 1;
962 log_syslog = 1;
963 continue;
964 }
965 if (!strcmp(arg, "--verbose")) {
966 verbose = 1;
967 continue;
968 }
969 if (!strcmp(arg, "--syslog")) {
970 log_syslog = 1;
971 continue;
972 }
973 if (!strcmp(arg, "--export-all")) {
974 export_all_trees = 1;
975 continue;
976 }
977 if (!prefixcmp(arg, "--timeout=")) {
978 timeout = atoi(arg+10);
979 continue;
980 }
981 if (!prefixcmp(arg, "--init-timeout=")) {
982 init_timeout = atoi(arg+15);
983 continue;
984 }
985 if (!prefixcmp(arg, "--max-connections=")) {
986 max_connections = atoi(arg+18);
987 if (max_connections < 0)
988 max_connections = 0; /* unlimited */
989 continue;
990 }
991 if (!strcmp(arg, "--strict-paths")) {
992 strict_paths = 1;
993 continue;
994 }
995 if (!prefixcmp(arg, "--base-path=")) {
996 base_path = arg+12;
997 continue;
998 }
999 if (!strcmp(arg, "--base-path-relaxed")) {
1000 base_path_relaxed = 1;
1001 continue;
1002 }
1003 if (!prefixcmp(arg, "--interpolated-path=")) {
1004 interpolated_path = arg+20;
1005 continue;
1006 }
1007 if (!strcmp(arg, "--reuseaddr")) {
1008 reuseaddr = 1;
1009 continue;
1010 }
1011 if (!strcmp(arg, "--user-path")) {
1012 user_path = "";
1013 continue;
1014 }
1015 if (!prefixcmp(arg, "--user-path=")) {
1016 user_path = arg + 12;
1017 continue;
1018 }
1019 if (!prefixcmp(arg, "--pid-file=")) {
1020 pid_file = arg + 11;
1021 continue;
1022 }
1023 if (!strcmp(arg, "--detach")) {
1024 detach = 1;
1025 log_syslog = 1;
1026 continue;
1027 }
1028 if (!prefixcmp(arg, "--user=")) {
1029 user_name = arg + 7;
1030 continue;
1031 }
1032 if (!prefixcmp(arg, "--group=")) {
1033 group_name = arg + 8;
1034 continue;
1035 }
1036 if (!prefixcmp(arg, "--enable=")) {
1037 enable_service(arg + 9, 1);
1038 continue;
1039 }
1040 if (!prefixcmp(arg, "--disable=")) {
1041 enable_service(arg + 10, 0);
1042 continue;
1043 }
1044 if (!prefixcmp(arg, "--allow-override=")) {
1045 make_service_overridable(arg + 17, 1);
1046 continue;
1047 }
1048 if (!prefixcmp(arg, "--forbid-override=")) {
1049 make_service_overridable(arg + 18, 0);
1050 continue;
1051 }
1052 if (!strcmp(arg, "--")) {
1053 ok_paths = &argv[i+1];
1054 break;
1055 } else if (arg[0] != '-') {
1056 ok_paths = &argv[i];
1057 break;
1058 }
1059 usage(daemon_usage);
1061 }
1062 if (log_syslog) {
1064 openlog("git-daemon", LOG_PID, LOG_DAEMON);
1065 set_die_routine(daemon_die);
1066 } else
1067 /* avoid splitting a message in the middle */
1068 setvbuf(stderr, NULL, _IOLBF, 0);
1069 if (inetd_mode && (group_name || user_name))
1071 die("--user and --group are incompatible with --inetd");
1072 if (inetd_mode && (listen_port || listen_addr))
1074 die("--listen= and --port= are incompatible with --inetd");
1075 else if (listen_port == 0)
1076 listen_port = DEFAULT_GIT_PORT;
1077 if (group_name && !user_name)
1079 die("--group supplied without --user");
1080 if (user_name) {
1082 pass = getpwnam(user_name);
1083 if (!pass)
1084 die("user not found - %s", user_name);
1085 if (!group_name)
1087 gid = pass->pw_gid;
1088 else {
1089 group = getgrnam(group_name);
1090 if (!group)
1091 die("group not found - %s", group_name);
1092 gid = group->gr_gid;
1094 }
1095 }
1096 if (strict_paths && (!ok_paths || !*ok_paths))
1098 die("option --strict-paths requires a whitelist");
1099 if (base_path && !is_directory(base_path))
1101 die("base-path '%s' does not exist or is not a directory",
1102 base_path);
1103 if (inetd_mode) {
1105 struct sockaddr_storage ss;
1106 struct sockaddr *peer = (struct sockaddr *)&ss;
1107 socklen_t slen = sizeof(ss);
1108 if (!freopen("/dev/null", "w", stderr))
1110 die("failed to redirect stderr to /dev/null: %s",
1111 strerror(errno));
1112 if (getpeername(0, peer, &slen))
1114 peer = NULL;
1115 return execute(peer);
1117 }
1118 if (detach) {
1120 daemonize();
1121 loginfo("Ready to rumble");
1122 }
1123 else
1124 sanitize_stdfds();
1125 if (pid_file)
1127 store_pid(pid_file);
1128 return serve(listen_addr, listen_port, pass, gid);
1130}