-#include "cache.h"
-#include "pkt-line.h"
#include <signal.h>
#include <sys/wait.h>
#include <sys/socket.h>
#include <sys/time.h>
+#include <sys/poll.h>
#include <netdb.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <syslog.h>
+#include "pkt-line.h"
+#include "cache.h"
+#include "exec_cmd.h"
static int log_syslog;
static int verbose;
+static int reuseaddr;
-static const char daemon_usage[] = "git-daemon [--verbose] [--syslog] [--inetd | --port=n] [--export-all] [directory...]";
+static const char daemon_usage[] =
+"git-daemon [--verbose] [--syslog] [--inetd | --port=n] [--export-all]\n"
+" [--timeout=n] [--init-timeout=n] [--strict-paths]\n"
+" [--base-path=path] [--user-path | --user-path=path]\n"
+" [--reuseaddr] [--detach] [--pid-file=file] [directory...]";
/* List of acceptable pathname prefixes */
static char **ok_paths = NULL;
+static int strict_paths = 0;
/* If this is set, git-daemon-export-ok is not required */
static int export_all_trees = 0;
+/* Take all paths relative to this one if non-NULL */
+static char *base_path = NULL;
+
+/* If defined, ~user notation is allowed and the string is inserted
+ * after ~user/. E.g. a request to git://host/~alice/frotz would
+ * go to /home/alice/pub_git/frotz with --user-path=pub_git.
+ */
+static const char *user_path = NULL;
+
+/* Timeout, and initial timeout */
+static unsigned int timeout = 0;
+static unsigned int init_timeout = 0;
static void logreport(int priority, const char *err, va_list params)
{
write(2, buf, buflen);
}
-void logerror(const char *err, ...)
+static void logerror(const char *err, ...)
{
va_list params;
va_start(params, err);
va_end(params);
}
-void loginfo(const char *err, ...)
+static void loginfo(const char *err, ...)
{
va_list params;
if (!verbose)
va_end(params);
}
-static int path_ok(const char *dir)
+static void NORETURN daemon_die(const char *err, va_list params)
{
- const char *p = dir;
- char **pp;
- int sl = 1, ndot = 0;
+ logreport(LOG_ERR, err, params);
+ exit(1);
+}
- for (;;) {
- if ( *p == '.' ) {
- ndot++;
- } else if ( *p == '/' || *p == '\0' ) {
- if ( sl && ndot > 0 && ndot < 3 )
- return 0; /* . or .. in path */
+static int avoid_alias(char *p)
+{
+ int sl, ndot;
+
+ /*
+ * This resurrects the belts and suspenders paranoia check by HPA
+ * done in <435560F7.4080006@zytor.com> thread, now enter_repo()
+ * does not do getcwd() based path canonicalizations.
+ *
+ * sl becomes true immediately after seeing '/' and continues to
+ * be true as long as dots continue after that without intervening
+ * non-dot character.
+ */
+ if (!p || (*p != '/' && *p != '~'))
+ return -1;
+ sl = 1; ndot = 0;
+ p++;
+
+ while (1) {
+ char ch = *p++;
+ if (sl) {
+ if (ch == '.')
+ ndot++;
+ else if (ch == '/') {
+ if (ndot < 3)
+ /* reject //, /./ and /../ */
+ return -1;
+ ndot = 0;
+ }
+ else if (ch == 0) {
+ if (0 < ndot && ndot < 3)
+ /* reject /.$ and /..$ */
+ return -1;
+ return 0;
+ }
+ else
+ sl = ndot = 0;
+ }
+ else if (ch == 0)
+ return 0;
+ else if (ch == '/') {
sl = 1;
- if ( *p == '\0' )
- break; /* End of string and all is good */
- } else {
- sl = ndot = 0;
+ ndot = 0;
}
- p++;
}
+}
- if ( ok_paths && *ok_paths ) {
- int ok = 0;
- int dirlen = strlen(dir); /* read_packet_line can return embedded \0 */
+static char *path_ok(char *dir)
+{
+ static char rpath[PATH_MAX];
+ char *path;
+
+ if (avoid_alias(dir)) {
+ logerror("'%s': aliased", dir);
+ return NULL;
+ }
+
+ if (*dir == '~') {
+ if (!user_path) {
+ logerror("'%s': User-path not allowed", dir);
+ return NULL;
+ }
+ if (*user_path) {
+ /* Got either "~alice" or "~alice/foo";
+ * rewrite them to "~alice/%s" or
+ * "~alice/%s/foo".
+ */
+ int namlen, restlen = strlen(dir);
+ char *slash = strchr(dir, '/');
+ if (!slash)
+ slash = dir + restlen;
+ namlen = slash - dir;
+ restlen -= namlen;
+ loginfo("userpath <%s>, request <%s>, namlen %d, restlen %d, slash <%s>", user_path, dir, namlen, restlen, slash);
+ snprintf(rpath, PATH_MAX, "%.*s/%s%.*s",
+ namlen, dir, user_path, restlen, slash);
+ dir = rpath;
+ }
+ }
+ else if (base_path) {
+ if (*dir != '/') {
+ /* Allow only absolute */
+ logerror("'%s': Non-absolute path denied (base-path active)", dir);
+ return NULL;
+ }
+ else {
+ snprintf(rpath, PATH_MAX, "%s%s", base_path, dir);
+ dir = rpath;
+ }
+ }
+
+ path = enter_repo(dir, strict_paths);
+
+ if (!path) {
+ logerror("'%s': unable to chdir or not a git archive", dir);
+ return NULL;
+ }
+ if ( ok_paths && *ok_paths ) {
+ char **pp;
+ int pathlen = strlen(path);
+
+ /* The validation is done on the paths after enter_repo
+ * appends optional {.git,.git/.git} and friends, but
+ * it does not use getcwd(). So if your /pub is
+ * a symlink to /mnt/pub, you can whitelist /pub and
+ * do not have to say /mnt/pub.
+ * Do not say /pub/.
+ */
for ( pp = ok_paths ; *pp ; pp++ ) {
int len = strlen(*pp);
- if ( len <= dirlen &&
- !strncmp(*pp, dir, len) &&
- (dir[len] == '/' || dir[len] == '\0') ) {
- ok = 1;
- break;
- }
+ if (len <= pathlen &&
+ !memcmp(*pp, path, len) &&
+ (path[len] == '\0' ||
+ (!strict_paths && path[len] == '/')))
+ return path;
}
-
- if ( !ok )
- return 0; /* Path not in whitelist */
+ }
+ else {
+ /* be backwards compatible */
+ if (!strict_paths)
+ return path;
}
- return 1; /* Path acceptable */
+ logerror("'%s': not in whitelist", path);
+ return NULL; /* Fallthrough. Deny by default */
}
-static int upload(char *dir, int dirlen)
+static int upload(char *dir)
{
- loginfo("Request for '%s'", dir);
+ /* Timeout as string */
+ char timeout_buf[64];
+ const char *path;
- if (!path_ok(dir)) {
- logerror("Forbidden directory: %s\n", dir);
- return -1;
- }
+ loginfo("Request for '%s'", dir);
- if (chdir(dir) < 0) {
- logerror("Cannot chdir('%s'): %s", dir, strerror(errno));
+ if (!(path = path_ok(dir)))
return -1;
- }
/*
* Security on the cheap.
*
- * We want a readable HEAD, usable "objects" directory, and
+ * We want a readable HEAD, usable "objects" directory, and
* a "git-daemon-export-ok" flag that says that the other side
* is ok with us doing this.
+ *
+ * path_ok() uses enter_repo() and does whitelist checking.
+ * We only need to make sure the repository is exported.
*/
- if ((!export_all_trees && access("git-daemon-export-ok", F_OK)) ||
- access("objects/00", X_OK) ||
- access("HEAD", R_OK)) {
- logerror("Not a valid git-daemon-enabled repository: '%s'", dir);
+
+ if (!export_all_trees && access("git-daemon-export-ok", F_OK)) {
+ logerror("'%s': repository not exported.", path);
+ errno = EACCES;
return -1;
}
*/
signal(SIGTERM, SIG_IGN);
+ snprintf(timeout_buf, sizeof timeout_buf, "--timeout=%u", timeout);
+
/* git-upload-pack only ever reads stuff, so this is safe */
- execlp("git-upload-pack", "git-upload-pack", ".", NULL);
+ execl_git_cmd("upload-pack", "--strict", timeout_buf, ".", NULL);
return -1;
}
-static int execute(void)
+static int execute(struct sockaddr *addr)
{
static char line[1000];
- int len;
+ int pktlen, len;
+
+ if (addr) {
+ char addrbuf[256] = "";
+ int port = -1;
+
+ if (addr->sa_family == AF_INET) {
+ struct sockaddr_in *sin_addr = (void *) addr;
+ inet_ntop(addr->sa_family, &sin_addr->sin_addr, addrbuf, sizeof(addrbuf));
+ port = sin_addr->sin_port;
+#ifndef NO_IPV6
+ } else if (addr && addr->sa_family == AF_INET6) {
+ struct sockaddr_in6 *sin6_addr = (void *) addr;
+
+ char *buf = addrbuf;
+ *buf++ = '['; *buf = '\0'; /* stpcpy() is cool */
+ inet_ntop(AF_INET6, &sin6_addr->sin6_addr, buf, sizeof(addrbuf) - 1);
+ strcat(buf, "]");
+
+ port = sin6_addr->sin6_port;
+#endif
+ }
+ loginfo("Connection from %s:%d", addrbuf, port);
+ }
- len = packet_read_line(0, line, sizeof(line));
+ alarm(init_timeout ? init_timeout : timeout);
+ pktlen = packet_read_line(0, line, sizeof(line));
+ alarm(0);
+ len = strlen(line);
+ if (pktlen != len)
+ loginfo("Extended attributes (%d bytes) exist <%.*s>",
+ (int) pktlen - len,
+ (int) pktlen - len, line + len + 1);
if (len && line[len-1] == '\n')
line[--len] = 0;
- if (!strncmp("git-upload-pack /", line, 17))
- return upload(line + 16, len - 16);
+ if (!strncmp("git-upload-pack ", line, 16))
+ return upload(line+16);
logerror("Protocol error: '%s'", line);
return -1;
static void handle(int incoming, struct sockaddr *addr, int addrlen)
{
pid_t pid = fork();
- char addrbuf[256] = "";
- int port = -1;
if (pid) {
unsigned idx;
dup2(incoming, 1);
close(incoming);
- if (addr->sa_family == AF_INET) {
- struct sockaddr_in *sin_addr = (void *) addr;
- inet_ntop(AF_INET, &sin_addr->sin_addr, addrbuf, sizeof(addrbuf));
- port = sin_addr->sin_port;
-
- } else if (addr->sa_family == AF_INET6) {
- struct sockaddr_in6 *sin6_addr = (void *) addr;
-
- char *buf = addrbuf;
- *buf++ = '['; *buf = '\0'; /* stpcpy() is cool */
- inet_ntop(AF_INET6, &sin6_addr->sin6_addr, buf, sizeof(addrbuf) - 1);
- strcat(buf, "]");
-
- port = sin6_addr->sin6_port;
- }
- loginfo("Connection from %s:%d", addrbuf, port);
-
- exit(execute());
+ exit(execute(addr));
}
static void child_handler(int signo)
children_reaped = reaped + 1;
/* XXX: Custom logging, since we don't wanna getpid() */
if (verbose) {
- char *dead = "";
+ const char *dead = "";
if (!WIFEXITED(status) || WEXITSTATUS(status) > 0)
dead = " (with error)";
if (log_syslog)
}
}
-static int serve(int port)
+static int set_reuse_addr(int sockfd)
+{
+ int on = 1;
+
+ if (!reuseaddr)
+ return 0;
+ return setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR,
+ &on, sizeof(on));
+}
+
+#ifndef NO_IPV6
+
+static int socksetup(int port, int **socklist_p)
{
- struct addrinfo hints, *ai0, *ai;
- int gai;
int socknum = 0, *socklist = NULL;
int maxfd = -1;
- fd_set fds_init, fds;
char pbuf[NI_MAXSERV];
- signal(SIGCHLD, child_handler);
+ struct addrinfo hints, *ai0, *ai;
+ int gai;
sprintf(pbuf, "%d", port);
memset(&hints, 0, sizeof(hints));
if (gai)
die("getaddrinfo() failed: %s\n", gai_strerror(gai));
- FD_ZERO(&fds_init);
-
for (ai = ai0; ai; ai = ai->ai_next) {
int sockfd;
int *newlist;
}
#endif
+ if (set_reuse_addr(sockfd)) {
+ close(sockfd);
+ continue;
+ }
+
if (bind(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
close(sockfd);
continue; /* not fatal */
socklist = newlist;
socklist[socknum++] = sockfd;
- FD_SET(sockfd, &fds_init);
if (maxfd < sockfd)
maxfd = sockfd;
}
freeaddrinfo(ai0);
- if (socknum == 0)
- die("unable to allocate any listen sockets on port %u", port);
+ *socklist_p = socklist;
+ return socknum;
+}
+
+#else /* NO_IPV6 */
+
+static int socksetup(int port, int **socklist_p)
+{
+ struct sockaddr_in sin;
+ int sockfd;
+
+ sockfd = socket(AF_INET, SOCK_STREAM, 0);
+ if (sockfd < 0)
+ return 0;
+
+ memset(&sin, 0, sizeof sin);
+ sin.sin_family = AF_INET;
+ sin.sin_addr.s_addr = htonl(INADDR_ANY);
+ sin.sin_port = htons(port);
+
+ if (set_reuse_addr(sockfd)) {
+ close(sockfd);
+ return 0;
+ }
+
+ if ( bind(sockfd, (struct sockaddr *)&sin, sizeof sin) < 0 ) {
+ close(sockfd);
+ return 0;
+ }
+
+ if (listen(sockfd, 5) < 0) {
+ close(sockfd);
+ return 0;
+ }
+
+ *socklist_p = xmalloc(sizeof(int));
+ **socklist_p = sockfd;
+ return 1;
+}
+
+#endif
+
+static int service_loop(int socknum, int *socklist)
+{
+ struct pollfd *pfd;
+ int i;
+
+ pfd = xcalloc(socknum, sizeof(struct pollfd));
+
+ for (i = 0; i < socknum; i++) {
+ pfd[i].fd = socklist[i];
+ pfd[i].events = POLLIN;
+ }
+
+ signal(SIGCHLD, child_handler);
for (;;) {
int i;
- fds = fds_init;
-
- if (select(maxfd + 1, &fds, NULL, NULL, NULL) < 0) {
+
+ if (poll(pfd, socknum, -1) < 0) {
if (errno != EINTR) {
- error("select failed, resuming: %s",
+ error("poll failed, resuming: %s",
strerror(errno));
sleep(1);
}
}
for (i = 0; i < socknum; i++) {
- int sockfd = socklist[i];
-
- if (FD_ISSET(sockfd, &fds)) {
+ if (pfd[i].revents & POLLIN) {
struct sockaddr_storage ss;
- int sslen = sizeof(ss);
- int incoming = accept(sockfd, (struct sockaddr *)&ss, &sslen);
+ unsigned int sslen = sizeof(ss);
+ int incoming = accept(pfd[i].fd, (struct sockaddr *)&ss, &sslen);
if (incoming < 0) {
switch (errno) {
case EAGAIN:
}
}
+/* if any standard file descriptor is missing open it to /dev/null */
+static void sanitize_stdfds(void)
+{
+ int fd = open("/dev/null", O_RDWR, 0);
+ while (fd != -1 && fd < 2)
+ fd = dup(fd);
+ if (fd == -1)
+ die("open /dev/null or dup failed: %s", strerror(errno));
+ if (fd > 2)
+ close(fd);
+}
+
+static void daemonize(void)
+{
+ switch (fork()) {
+ case 0:
+ break;
+ case -1:
+ die("fork failed: %s", strerror(errno));
+ default:
+ exit(0);
+ }
+ if (setsid() == -1)
+ die("setsid failed: %s", strerror(errno));
+ close(0);
+ close(1);
+ close(2);
+ sanitize_stdfds();
+}
+
+static void store_pid(const char *path)
+{
+ FILE *f = fopen(path, "w");
+ if (!f)
+ die("cannot open pid file %s: %s", path, strerror(errno));
+ fprintf(f, "%d\n", getpid());
+ fclose(f);
+}
+
+static int serve(int port)
+{
+ int socknum, *socklist;
+
+ socknum = socksetup(port, &socklist);
+ if (socknum == 0)
+ die("unable to allocate any listen sockets on port %u", port);
+
+ return service_loop(socknum, socklist);
+}
+
int main(int argc, char **argv)
{
int port = DEFAULT_GIT_PORT;
int inetd_mode = 0;
+ const char *pid_file = NULL;
+ int detach = 0;
int i;
+ /* Without this we cannot rely on waitpid() to tell
+ * what happened to our children.
+ */
+ signal(SIGCHLD, SIG_DFL);
+
for (i = 1; i < argc; i++) {
char *arg = argv[i];
}
if (!strcmp(arg, "--inetd")) {
inetd_mode = 1;
+ log_syslog = 1;
continue;
}
if (!strcmp(arg, "--verbose")) {
}
if (!strcmp(arg, "--syslog")) {
log_syslog = 1;
- openlog("git-daemon", 0, LOG_DAEMON);
continue;
}
if (!strcmp(arg, "--export-all")) {
export_all_trees = 1;
continue;
}
+ if (!strncmp(arg, "--timeout=", 10)) {
+ timeout = atoi(arg+10);
+ continue;
+ }
+ if (!strncmp(arg, "--init-timeout=", 15)) {
+ init_timeout = atoi(arg+15);
+ continue;
+ }
+ if (!strcmp(arg, "--strict-paths")) {
+ strict_paths = 1;
+ continue;
+ }
+ if (!strncmp(arg, "--base-path=", 12)) {
+ base_path = arg+12;
+ continue;
+ }
+ if (!strcmp(arg, "--reuseaddr")) {
+ reuseaddr = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--user-path")) {
+ user_path = "";
+ continue;
+ }
+ if (!strncmp(arg, "--user-path=", 12)) {
+ user_path = arg + 12;
+ continue;
+ }
+ if (!strncmp(arg, "--pid-file=", 11)) {
+ pid_file = arg + 11;
+ continue;
+ }
+ if (!strcmp(arg, "--detach")) {
+ detach = 1;
+ log_syslog = 1;
+ continue;
+ }
if (!strcmp(arg, "--")) {
ok_paths = &argv[i+1];
break;
usage(daemon_usage);
}
+ if (log_syslog) {
+ openlog("git-daemon", 0, LOG_DAEMON);
+ set_die_routine(daemon_die);
+ }
+
+ if (strict_paths && (!ok_paths || !*ok_paths))
+ die("option --strict-paths requires a whitelist");
+
if (inetd_mode) {
- fclose(stderr); //FIXME: workaround
- return execute();
+ struct sockaddr_storage ss;
+ struct sockaddr *peer = (struct sockaddr *)&ss;
+ socklen_t slen = sizeof(ss);
+
+ freopen("/dev/null", "w", stderr);
+
+ if (getpeername(0, peer, &slen))
+ peer = NULL;
+
+ return execute(peer);
}
+ if (detach)
+ daemonize();
+ else
+ sanitize_stdfds();
+
+ if (pid_file)
+ store_pid(pid_file);
+
return serve(port);
}