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-rw-r--r--daemon.c1331
1 files changed, 1331 insertions, 0 deletions
diff --git a/daemon.c b/daemon.c
new file mode 100644
index 0000000000..eba1255684
--- /dev/null
+++ b/daemon.c
@@ -0,0 +1,1331 @@
+#include "cache.h"
+#include "pkt-line.h"
+#include "exec_cmd.h"
+#include "run-command.h"
+#include "strbuf.h"
+#include "string-list.h"
+
+#ifndef HOST_NAME_MAX
+#define HOST_NAME_MAX 256
+#endif
+
+#ifdef NO_INITGROUPS
+#define initgroups(x, y) (0) /* nothing */
+#endif
+
+static int log_syslog;
+static int verbose;
+static int reuseaddr;
+static int informative_errors;
+
+static const char daemon_usage[] =
+"git daemon [--verbose] [--syslog] [--export-all]\n"
+" [--timeout=<n>] [--init-timeout=<n>] [--max-connections=<n>]\n"
+" [--strict-paths] [--base-path=<path>] [--base-path-relaxed]\n"
+" [--user-path | --user-path=<path>]\n"
+" [--interpolated-path=<path>]\n"
+" [--reuseaddr] [--pid-file=<file>]\n"
+" [--(enable|disable|allow-override|forbid-override)=<service>]\n"
+" [--access-hook=<path>]\n"
+" [--inetd | [--listen=<host_or_ipaddr>] [--port=<n>]\n"
+" [--detach] [--user=<user> [--group=<group>]]\n"
+" [<directory>...]";
+
+/* List of acceptable pathname prefixes */
+static char **ok_paths;
+static int strict_paths;
+
+/* If this is set, git-daemon-export-ok is not required */
+static int export_all_trees;
+
+/* Take all paths relative to this one if non-NULL */
+static char *base_path;
+static char *interpolated_path;
+static int base_path_relaxed;
+
+/* Flag indicating client sent extra args. */
+static int saw_extended_args;
+
+/* 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;
+
+/* Timeout, and initial timeout */
+static unsigned int timeout;
+static unsigned int init_timeout;
+
+static char *hostname;
+static char *canon_hostname;
+static char *ip_address;
+static char *tcp_port;
+
+static void logreport(int priority, const char *err, va_list params)
+{
+ if (log_syslog) {
+ char buf[1024];
+ vsnprintf(buf, sizeof(buf), err, params);
+ syslog(priority, "%s", buf);
+ } else {
+ /*
+ * Since stderr is set to buffered mode, the
+ * logging of different processes will not overlap
+ * unless they overflow the (rather big) buffers.
+ */
+ fprintf(stderr, "[%"PRIuMAX"] ", (uintmax_t)getpid());
+ vfprintf(stderr, err, params);
+ fputc('\n', stderr);
+ fflush(stderr);
+ }
+}
+
+__attribute__((format (printf, 1, 2)))
+static void logerror(const char *err, ...)
+{
+ va_list params;
+ va_start(params, err);
+ logreport(LOG_ERR, err, params);
+ va_end(params);
+}
+
+__attribute__((format (printf, 1, 2)))
+static void loginfo(const char *err, ...)
+{
+ va_list params;
+ if (!verbose)
+ return;
+ va_start(params, err);
+ logreport(LOG_INFO, err, params);
+ va_end(params);
+}
+
+static void NORETURN daemon_die(const char *err, va_list params)
+{
+ logreport(LOG_ERR, err, params);
+ exit(1);
+}
+
+static const char *path_ok(char *directory)
+{
+ static char rpath[PATH_MAX];
+ static char interp_path[PATH_MAX];
+ const char *path;
+ char *dir;
+
+ dir = directory;
+
+ if (daemon_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 (interpolated_path && saw_extended_args) {
+ struct strbuf expanded_path = STRBUF_INIT;
+ struct strbuf_expand_dict_entry dict[6];
+
+ dict[0].placeholder = "H"; dict[0].value = hostname;
+ dict[1].placeholder = "CH"; dict[1].value = canon_hostname;
+ dict[2].placeholder = "IP"; dict[2].value = ip_address;
+ dict[3].placeholder = "P"; dict[3].value = tcp_port;
+ dict[4].placeholder = "D"; dict[4].value = directory;
+ dict[5].placeholder = NULL; dict[5].value = NULL;
+ if (*dir != '/') {
+ /* Allow only absolute */
+ logerror("'%s': Non-absolute path denied (interpolated-path active)", dir);
+ return NULL;
+ }
+
+ strbuf_expand(&expanded_path, interpolated_path,
+ strbuf_expand_dict_cb, &dict);
+ strlcpy(interp_path, expanded_path.buf, PATH_MAX);
+ strbuf_release(&expanded_path);
+ loginfo("Interpolated dir '%s'", interp_path);
+
+ dir = interp_path;
+ }
+ else if (base_path) {
+ if (*dir != '/') {
+ /* Allow only absolute */
+ logerror("'%s': Non-absolute path denied (base-path active)", dir);
+ return NULL;
+ }
+ snprintf(rpath, PATH_MAX, "%s%s", base_path, dir);
+ dir = rpath;
+ }
+
+ path = enter_repo(dir, strict_paths);
+ if (!path && base_path && base_path_relaxed) {
+ /*
+ * if we fail and base_path_relaxed is enabled, try without
+ * prefixing the base path
+ */
+ dir = directory;
+ path = enter_repo(dir, strict_paths);
+ }
+
+ if (!path) {
+ logerror("'%s' does not appear to be a git repository", 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 <= pathlen &&
+ !memcmp(*pp, path, len) &&
+ (path[len] == '\0' ||
+ (!strict_paths && path[len] == '/')))
+ return path;
+ }
+ }
+ else {
+ /* be backwards compatible */
+ if (!strict_paths)
+ return path;
+ }
+
+ logerror("'%s': not in whitelist", path);
+ return NULL; /* Fallthrough. Deny by default */
+}
+
+typedef int (*daemon_service_fn)(void);
+struct daemon_service {
+ const char *name;
+ const char *config_name;
+ daemon_service_fn fn;
+ int enabled;
+ int overridable;
+};
+
+static struct daemon_service *service_looking_at;
+static int service_enabled;
+
+static int git_daemon_config(const char *var, const char *value, void *cb)
+{
+ if (starts_with(var, "daemon.") &&
+ !strcmp(var + 7, service_looking_at->config_name)) {
+ service_enabled = git_config_bool(var, value);
+ return 0;
+ }
+
+ /* we are not interested in parsing any other configuration here */
+ return 0;
+}
+
+static int daemon_error(const char *dir, const char *msg)
+{
+ if (!informative_errors)
+ msg = "access denied or repository not exported";
+ packet_write(1, "ERR %s: %s", msg, dir);
+ return -1;
+}
+
+static char *access_hook;
+
+static int run_access_hook(struct daemon_service *service, const char *dir, const char *path)
+{
+ struct child_process child;
+ struct strbuf buf = STRBUF_INIT;
+ const char *argv[8];
+ const char **arg = argv;
+ char *eol;
+ int seen_errors = 0;
+
+#define STRARG(x) ((x) ? (x) : "")
+ *arg++ = access_hook;
+ *arg++ = service->name;
+ *arg++ = path;
+ *arg++ = STRARG(hostname);
+ *arg++ = STRARG(canon_hostname);
+ *arg++ = STRARG(ip_address);
+ *arg++ = STRARG(tcp_port);
+ *arg = NULL;
+#undef STRARG
+
+ memset(&child, 0, sizeof(child));
+ child.use_shell = 1;
+ child.argv = argv;
+ child.no_stdin = 1;
+ child.no_stderr = 1;
+ child.out = -1;
+ if (start_command(&child)) {
+ logerror("daemon access hook '%s' failed to start",
+ access_hook);
+ goto error_return;
+ }
+ if (strbuf_read(&buf, child.out, 0) < 0) {
+ logerror("failed to read from pipe to daemon access hook '%s'",
+ access_hook);
+ strbuf_reset(&buf);
+ seen_errors = 1;
+ }
+ if (close(child.out) < 0) {
+ logerror("failed to close pipe to daemon access hook '%s'",
+ access_hook);
+ seen_errors = 1;
+ }
+ if (finish_command(&child))
+ seen_errors = 1;
+
+ if (!seen_errors) {
+ strbuf_release(&buf);
+ return 0;
+ }
+
+error_return:
+ strbuf_ltrim(&buf);
+ if (!buf.len)
+ strbuf_addstr(&buf, "service rejected");
+ eol = strchr(buf.buf, '\n');
+ if (eol)
+ *eol = '\0';
+ errno = EACCES;
+ daemon_error(dir, buf.buf);
+ strbuf_release(&buf);
+ return -1;
+}
+
+static int run_service(char *dir, struct daemon_service *service)
+{
+ const char *path;
+ int enabled = service->enabled;
+
+ loginfo("Request %s for '%s'", service->name, dir);
+
+ if (!enabled && !service->overridable) {
+ logerror("'%s': service not enabled.", service->name);
+ errno = EACCES;
+ return daemon_error(dir, "service not enabled");
+ }
+
+ if (!(path = path_ok(dir)))
+ return daemon_error(dir, "no such repository");
+
+ /*
+ * Security on the cheap.
+ *
+ * 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)) {
+ logerror("'%s': repository not exported.", path);
+ errno = EACCES;
+ return daemon_error(dir, "repository not exported");
+ }
+
+ if (service->overridable) {
+ service_looking_at = service;
+ service_enabled = -1;
+ git_config(git_daemon_config, NULL);
+ if (0 <= service_enabled)
+ enabled = service_enabled;
+ }
+ if (!enabled) {
+ logerror("'%s': service not enabled for '%s'",
+ service->name, path);
+ errno = EACCES;
+ return daemon_error(dir, "service not enabled");
+ }
+
+ /*
+ * Optionally, a hook can choose to deny access to the
+ * repository depending on the phase of the moon.
+ */
+ if (access_hook && run_access_hook(service, dir, path))
+ return -1;
+
+ /*
+ * We'll ignore SIGTERM from now on, we have a
+ * good client.
+ */
+ signal(SIGTERM, SIG_IGN);
+
+ return service->fn();
+}
+
+static void copy_to_log(int fd)
+{
+ struct strbuf line = STRBUF_INIT;
+ FILE *fp;
+
+ fp = fdopen(fd, "r");
+ if (fp == NULL) {
+ logerror("fdopen of error channel failed");
+ close(fd);
+ return;
+ }
+
+ while (strbuf_getline(&line, fp, '\n') != EOF) {
+ logerror("%s", line.buf);
+ strbuf_setlen(&line, 0);
+ }
+
+ strbuf_release(&line);
+ fclose(fp);
+}
+
+static int run_service_command(const char **argv)
+{
+ struct child_process cld;
+
+ memset(&cld, 0, sizeof(cld));
+ cld.argv = argv;
+ cld.git_cmd = 1;
+ cld.err = -1;
+ if (start_command(&cld))
+ return -1;
+
+ close(0);
+ close(1);
+
+ copy_to_log(cld.err);
+
+ return finish_command(&cld);
+}
+
+static int upload_pack(void)
+{
+ /* Timeout as string */
+ char timeout_buf[64];
+ const char *argv[] = { "upload-pack", "--strict", NULL, ".", NULL };
+
+ argv[2] = timeout_buf;
+
+ snprintf(timeout_buf, sizeof timeout_buf, "--timeout=%u", timeout);
+ return run_service_command(argv);
+}
+
+static int upload_archive(void)
+{
+ static const char *argv[] = { "upload-archive", ".", NULL };
+ return run_service_command(argv);
+}
+
+static int receive_pack(void)
+{
+ static const char *argv[] = { "receive-pack", ".", NULL };
+ return run_service_command(argv);
+}
+
+static struct daemon_service daemon_service[] = {
+ { "upload-archive", "uploadarch", upload_archive, 0, 1 },
+ { "upload-pack", "uploadpack", upload_pack, 1, 1 },
+ { "receive-pack", "receivepack", receive_pack, 0, 1 },
+};
+
+static void enable_service(const char *name, int ena)
+{
+ int i;
+ for (i = 0; i < ARRAY_SIZE(daemon_service); i++) {
+ if (!strcmp(daemon_service[i].name, name)) {
+ daemon_service[i].enabled = ena;
+ return;
+ }
+ }
+ die("No such service %s", name);
+}
+
+static void make_service_overridable(const char *name, int ena)
+{
+ int i;
+ for (i = 0; i < ARRAY_SIZE(daemon_service); i++) {
+ if (!strcmp(daemon_service[i].name, name)) {
+ daemon_service[i].overridable = ena;
+ return;
+ }
+ }
+ die("No such service %s", name);
+}
+
+static char *xstrdup_tolower(const char *str)
+{
+ char *p, *dup = xstrdup(str);
+ for (p = dup; *p; p++)
+ *p = tolower(*p);
+ return dup;
+}
+
+static void parse_host_and_port(char *hostport, char **host,
+ char **port)
+{
+ if (*hostport == '[') {
+ char *end;
+
+ end = strchr(hostport, ']');
+ if (!end)
+ die("Invalid request ('[' without ']')");
+ *end = '\0';
+ *host = hostport + 1;
+ if (!end[1])
+ *port = NULL;
+ else if (end[1] == ':')
+ *port = end + 2;
+ else
+ die("Garbage after end of host part");
+ } else {
+ *host = hostport;
+ *port = strrchr(hostport, ':');
+ if (*port) {
+ **port = '\0';
+ ++*port;
+ }
+ }
+}
+
+/*
+ * Read the host as supplied by the client connection.
+ */
+static void parse_host_arg(char *extra_args, int buflen)
+{
+ char *val;
+ int vallen;
+ char *end = extra_args + buflen;
+
+ if (extra_args < end && *extra_args) {
+ saw_extended_args = 1;
+ if (strncasecmp("host=", extra_args, 5) == 0) {
+ val = extra_args + 5;
+ vallen = strlen(val) + 1;
+ if (*val) {
+ /* Split <host>:<port> at colon. */
+ char *host;
+ char *port;
+ parse_host_and_port(val, &host, &port);
+ if (port) {
+ free(tcp_port);
+ tcp_port = xstrdup(port);
+ }
+ free(hostname);
+ hostname = xstrdup_tolower(host);
+ }
+
+ /* On to the next one */
+ extra_args = val + vallen;
+ }
+ if (extra_args < end && *extra_args)
+ die("Invalid request");
+ }
+
+ /*
+ * Locate canonical hostname and its IP address.
+ */
+ if (hostname) {
+#ifndef NO_IPV6
+ struct addrinfo hints;
+ struct addrinfo *ai;
+ int gai;
+ static char addrbuf[HOST_NAME_MAX + 1];
+
+ memset(&hints, 0, sizeof(hints));
+ hints.ai_flags = AI_CANONNAME;
+
+ gai = getaddrinfo(hostname, NULL, &hints, &ai);
+ if (!gai) {
+ struct sockaddr_in *sin_addr = (void *)ai->ai_addr;
+
+ inet_ntop(AF_INET, &sin_addr->sin_addr,
+ addrbuf, sizeof(addrbuf));
+ free(ip_address);
+ ip_address = xstrdup(addrbuf);
+
+ free(canon_hostname);
+ canon_hostname = xstrdup(ai->ai_canonname ?
+ ai->ai_canonname : ip_address);
+
+ freeaddrinfo(ai);
+ }
+#else
+ struct hostent *hent;
+ struct sockaddr_in sa;
+ char **ap;
+ static char addrbuf[HOST_NAME_MAX + 1];
+
+ hent = gethostbyname(hostname);
+
+ ap = hent->h_addr_list;
+ memset(&sa, 0, sizeof sa);
+ sa.sin_family = hent->h_addrtype;
+ sa.sin_port = htons(0);
+ memcpy(&sa.sin_addr, *ap, hent->h_length);
+
+ inet_ntop(hent->h_addrtype, &sa.sin_addr,
+ addrbuf, sizeof(addrbuf));
+
+ free(canon_hostname);
+ canon_hostname = xstrdup(hent->h_name);
+ free(ip_address);
+ ip_address = xstrdup(addrbuf);
+#endif
+ }
+}
+
+
+static int execute(void)
+{
+ char *line = packet_buffer;
+ int pktlen, len, i;
+ char *addr = getenv("REMOTE_ADDR"), *port = getenv("REMOTE_PORT");
+
+ if (addr)
+ loginfo("Connection from %s:%s", addr, port);
+
+ alarm(init_timeout ? init_timeout : timeout);
+ pktlen = packet_read(0, NULL, NULL, packet_buffer, sizeof(packet_buffer), 0);
+ 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;
+ pktlen--;
+ }
+
+ free(hostname);
+ free(canon_hostname);
+ free(ip_address);
+ free(tcp_port);
+ hostname = canon_hostname = ip_address = tcp_port = NULL;
+
+ if (len != pktlen)
+ parse_host_arg(line + len + 1, pktlen - len - 1);
+
+ for (i = 0; i < ARRAY_SIZE(daemon_service); i++) {
+ struct daemon_service *s = &(daemon_service[i]);
+ int namelen = strlen(s->name);
+ if (starts_with(line, "git-") &&
+ !strncmp(s->name, line + 4, namelen) &&
+ line[namelen + 4] == ' ') {
+ /*
+ * Note: The directory here is probably context sensitive,
+ * and might depend on the actual service being performed.
+ */
+ return run_service(line + namelen + 5, s);
+ }
+ }
+
+ logerror("Protocol error: '%s'", line);
+ return -1;
+}
+
+static int addrcmp(const struct sockaddr_storage *s1,
+ const struct sockaddr_storage *s2)
+{
+ const struct sockaddr *sa1 = (const struct sockaddr*) s1;
+ const struct sockaddr *sa2 = (const struct sockaddr*) s2;
+
+ if (sa1->sa_family != sa2->sa_family)
+ return sa1->sa_family - sa2->sa_family;
+ if (sa1->sa_family == AF_INET)
+ return memcmp(&((struct sockaddr_in *)s1)->sin_addr,
+ &((struct sockaddr_in *)s2)->sin_addr,
+ sizeof(struct in_addr));
+#ifndef NO_IPV6
+ if (sa1->sa_family == AF_INET6)
+ return memcmp(&((struct sockaddr_in6 *)s1)->sin6_addr,
+ &((struct sockaddr_in6 *)s2)->sin6_addr,
+ sizeof(struct in6_addr));
+#endif
+ return 0;
+}
+
+static int max_connections = 32;
+
+static unsigned int live_children;
+
+static struct child {
+ struct child *next;
+ struct child_process cld;
+ struct sockaddr_storage address;
+} *firstborn;
+
+static void add_child(struct child_process *cld, struct sockaddr *addr, socklen_t addrlen)
+{
+ struct child *newborn, **cradle;
+
+ newborn = xcalloc(1, sizeof(*newborn));
+ live_children++;
+ memcpy(&newborn->cld, cld, sizeof(*cld));
+ memcpy(&newborn->address, addr, addrlen);
+ for (cradle = &firstborn; *cradle; cradle = &(*cradle)->next)
+ if (!addrcmp(&(*cradle)->address, &newborn->address))
+ break;
+ newborn->next = *cradle;
+ *cradle = newborn;
+}
+
+/*
+ * This gets called if the number of connections grows
+ * past "max_connections".
+ *
+ * We kill the newest connection from a duplicate IP.
+ */
+static void kill_some_child(void)
+{
+ const struct child *blanket, *next;
+
+ if (!(blanket = firstborn))
+ return;
+
+ for (; (next = blanket->next); blanket = next)
+ if (!addrcmp(&blanket->address, &next->address)) {
+ kill(blanket->cld.pid, SIGTERM);
+ break;
+ }
+}
+
+static void check_dead_children(void)
+{
+ int status;
+ pid_t pid;
+
+ struct child **cradle, *blanket;
+ for (cradle = &firstborn; (blanket = *cradle);)
+ if ((pid = waitpid(blanket->cld.pid, &status, WNOHANG)) > 1) {
+ const char *dead = "";
+ if (status)
+ dead = " (with error)";
+ loginfo("[%"PRIuMAX"] Disconnected%s", (uintmax_t)pid, dead);
+
+ /* remove the child */
+ *cradle = blanket->next;
+ live_children--;
+ free(blanket);
+ } else
+ cradle = &blanket->next;
+}
+
+static char **cld_argv;
+static void handle(int incoming, struct sockaddr *addr, socklen_t addrlen)
+{
+ struct child_process cld = { NULL };
+ char addrbuf[300] = "REMOTE_ADDR=", portbuf[300];
+ char *env[] = { addrbuf, portbuf, NULL };
+
+ if (max_connections && live_children >= max_connections) {
+ kill_some_child();
+ sleep(1); /* give it some time to die */
+ check_dead_children();
+ if (live_children >= max_connections) {
+ close(incoming);
+ logerror("Too many children, dropping connection");
+ return;
+ }
+ }
+
+ if (addr->sa_family == AF_INET) {
+ struct sockaddr_in *sin_addr = (void *) addr;
+ inet_ntop(addr->sa_family, &sin_addr->sin_addr, addrbuf + 12,
+ sizeof(addrbuf) - 12);
+ snprintf(portbuf, sizeof(portbuf), "REMOTE_PORT=%d",
+ ntohs(sin_addr->sin_port));
+#ifndef NO_IPV6
+ } else if (addr->sa_family == AF_INET6) {
+ struct sockaddr_in6 *sin6_addr = (void *) addr;
+
+ char *buf = addrbuf + 12;
+ *buf++ = '['; *buf = '\0'; /* stpcpy() is cool */
+ inet_ntop(AF_INET6, &sin6_addr->sin6_addr, buf,
+ sizeof(addrbuf) - 13);
+ strcat(buf, "]");
+
+ snprintf(portbuf, sizeof(portbuf), "REMOTE_PORT=%d",
+ ntohs(sin6_addr->sin6_port));
+#endif
+ }
+
+ cld.env = (const char **)env;
+ cld.argv = (const char **)cld_argv;
+ cld.in = incoming;
+ cld.out = dup(incoming);
+
+ if (start_command(&cld))
+ logerror("unable to fork");
+ else
+ add_child(&cld, addr, addrlen);
+ close(incoming);
+}
+
+static void child_handler(int signo)
+{
+ /*
+ * Otherwise empty handler because systemcalls will get interrupted
+ * upon signal receipt
+ * SysV needs the handler to be rearmed
+ */
+ signal(SIGCHLD, child_handler);
+}
+
+static int set_reuse_addr(int sockfd)
+{
+ int on = 1;
+
+ if (!reuseaddr)
+ return 0;
+ return setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR,
+ &on, sizeof(on));
+}
+
+struct socketlist {
+ int *list;
+ size_t nr;
+ size_t alloc;
+};
+
+static const char *ip2str(int family, struct sockaddr *sin, socklen_t len)
+{
+#ifdef NO_IPV6
+ static char ip[INET_ADDRSTRLEN];
+#else
+ static char ip[INET6_ADDRSTRLEN];
+#endif
+
+ switch (family) {
+#ifndef NO_IPV6
+ case AF_INET6:
+ inet_ntop(family, &((struct sockaddr_in6*)sin)->sin6_addr, ip, len);
+ break;
+#endif
+ case AF_INET:
+ inet_ntop(family, &((struct sockaddr_in*)sin)->sin_addr, ip, len);
+ break;
+ default:
+ strcpy(ip, "<unknown>");
+ }
+ return ip;
+}
+
+#ifndef NO_IPV6
+
+static int setup_named_sock(char *listen_addr, int listen_port, struct socketlist *socklist)
+{
+ int socknum = 0;
+ int maxfd = -1;
+ char pbuf[NI_MAXSERV];
+ struct addrinfo hints, *ai0, *ai;
+ int gai;
+ long flags;
+
+ sprintf(pbuf, "%d", listen_port);
+ memset(&hints, 0, sizeof(hints));
+ hints.ai_family = AF_UNSPEC;
+ hints.ai_socktype = SOCK_STREAM;
+ hints.ai_protocol = IPPROTO_TCP;
+ hints.ai_flags = AI_PASSIVE;
+
+ gai = getaddrinfo(listen_addr, pbuf, &hints, &ai0);
+ if (gai) {
+ logerror("getaddrinfo() for %s failed: %s", listen_addr, gai_strerror(gai));
+ return 0;
+ }
+
+ for (ai = ai0; ai; ai = ai->ai_next) {
+ int sockfd;
+
+ sockfd = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
+ if (sockfd < 0)
+ continue;
+ if (sockfd >= FD_SETSIZE) {
+ logerror("Socket descriptor too large");
+ close(sockfd);
+ continue;
+ }
+
+#ifdef IPV6_V6ONLY
+ if (ai->ai_family == AF_INET6) {
+ int on = 1;
+ setsockopt(sockfd, IPPROTO_IPV6, IPV6_V6ONLY,
+ &on, sizeof(on));
+ /* Note: error is not fatal */
+ }
+#endif
+
+ if (set_reuse_addr(sockfd)) {
+ logerror("Could not set SO_REUSEADDR: %s", strerror(errno));
+ close(sockfd);
+ continue;
+ }
+
+ if (bind(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
+ logerror("Could not bind to %s: %s",
+ ip2str(ai->ai_family, ai->ai_addr, ai->ai_addrlen),
+ strerror(errno));
+ close(sockfd);
+ continue; /* not fatal */
+ }
+ if (listen(sockfd, 5) < 0) {
+ logerror("Could not listen to %s: %s",
+ ip2str(ai->ai_family, ai->ai_addr, ai->ai_addrlen),
+ strerror(errno));
+ close(sockfd);
+ continue; /* not fatal */
+ }
+
+ flags = fcntl(sockfd, F_GETFD, 0);
+ if (flags >= 0)
+ fcntl(sockfd, F_SETFD, flags | FD_CLOEXEC);
+
+ ALLOC_GROW(socklist->list, socklist->nr + 1, socklist->alloc);
+ socklist->list[socklist->nr++] = sockfd;
+ socknum++;
+
+ if (maxfd < sockfd)
+ maxfd = sockfd;
+ }
+
+ freeaddrinfo(ai0);
+
+ return socknum;
+}
+
+#else /* NO_IPV6 */
+
+static int setup_named_sock(char *listen_addr, int listen_port, struct socketlist *socklist)
+{
+ struct sockaddr_in sin;
+ int sockfd;
+ long flags;
+
+ memset(&sin, 0, sizeof sin);
+ sin.sin_family = AF_INET;
+ sin.sin_port = htons(listen_port);
+
+ if (listen_addr) {
+ /* Well, host better be an IP address here. */
+ if (inet_pton(AF_INET, listen_addr, &sin.sin_addr.s_addr) <= 0)
+ return 0;
+ } else {
+ sin.sin_addr.s_addr = htonl(INADDR_ANY);
+ }
+
+ sockfd = socket(AF_INET, SOCK_STREAM, 0);
+ if (sockfd < 0)
+ return 0;
+
+ if (set_reuse_addr(sockfd)) {
+ logerror("Could not set SO_REUSEADDR: %s", strerror(errno));
+ close(sockfd);
+ return 0;
+ }
+
+ if ( bind(sockfd, (struct sockaddr *)&sin, sizeof sin) < 0 ) {
+ logerror("Could not listen to %s: %s",
+ ip2str(AF_INET, (struct sockaddr *)&sin, sizeof(sin)),
+ strerror(errno));
+ close(sockfd);
+ return 0;
+ }
+
+ if (listen(sockfd, 5) < 0) {
+ logerror("Could not listen to %s: %s",
+ ip2str(AF_INET, (struct sockaddr *)&sin, sizeof(sin)),
+ strerror(errno));
+ close(sockfd);
+ return 0;
+ }
+
+ flags = fcntl(sockfd, F_GETFD, 0);
+ if (flags >= 0)
+ fcntl(sockfd, F_SETFD, flags | FD_CLOEXEC);
+
+ ALLOC_GROW(socklist->list, socklist->nr + 1, socklist->alloc);
+ socklist->list[socklist->nr++] = sockfd;
+ return 1;
+}
+
+#endif
+
+static void socksetup(struct string_list *listen_addr, int listen_port, struct socketlist *socklist)
+{
+ if (!listen_addr->nr)
+ setup_named_sock(NULL, listen_port, socklist);
+ else {
+ int i, socknum;
+ for (i = 0; i < listen_addr->nr; i++) {
+ socknum = setup_named_sock(listen_addr->items[i].string,
+ listen_port, socklist);
+
+ if (socknum == 0)
+ logerror("unable to allocate any listen sockets for host %s on port %u",
+ listen_addr->items[i].string, listen_port);
+ }
+ }
+}
+
+static int service_loop(struct socketlist *socklist)
+{
+ struct pollfd *pfd;
+ int i;
+
+ pfd = xcalloc(socklist->nr, sizeof(struct pollfd));
+
+ for (i = 0; i < socklist->nr; i++) {
+ pfd[i].fd = socklist->list[i];
+ pfd[i].events = POLLIN;
+ }
+
+ signal(SIGCHLD, child_handler);
+
+ for (;;) {
+ int i;
+
+ check_dead_children();
+
+ if (poll(pfd, socklist->nr, -1) < 0) {
+ if (errno != EINTR) {
+ logerror("Poll failed, resuming: %s",
+ strerror(errno));
+ sleep(1);
+ }
+ continue;
+ }
+
+ for (i = 0; i < socklist->nr; i++) {
+ if (pfd[i].revents & POLLIN) {
+ union {
+ struct sockaddr sa;
+ struct sockaddr_in sai;
+#ifndef NO_IPV6
+ struct sockaddr_in6 sai6;
+#endif
+ } ss;
+ socklen_t sslen = sizeof(ss);
+ int incoming = accept(pfd[i].fd, &ss.sa, &sslen);
+ if (incoming < 0) {
+ switch (errno) {
+ case EAGAIN:
+ case EINTR:
+ case ECONNABORTED:
+ continue;
+ default:
+ die_errno("accept returned");
+ }
+ }
+ handle(incoming, &ss.sa, sslen);
+ }
+ }
+ }
+}
+
+#ifdef NO_POSIX_GOODIES
+
+struct credentials;
+
+static void drop_privileges(struct credentials *cred)
+{
+ /* nothing */
+}
+
+static struct credentials *prepare_credentials(const char *user_name,
+ const char *group_name)
+{
+ die("--user not supported on this platform");
+}
+
+#else
+
+struct credentials {
+ struct passwd *pass;
+ gid_t gid;
+};
+
+static void drop_privileges(struct credentials *cred)
+{
+ if (cred && (initgroups(cred->pass->pw_name, cred->gid) ||
+ setgid (cred->gid) || setuid(cred->pass->pw_uid)))
+ die("cannot drop privileges");
+}
+
+static struct credentials *prepare_credentials(const char *user_name,
+ const char *group_name)
+{
+ static struct credentials c;
+
+ c.pass = getpwnam(user_name);
+ if (!c.pass)
+ die("user not found - %s", user_name);
+
+ if (!group_name)
+ c.gid = c.pass->pw_gid;
+ else {
+ struct group *group = getgrnam(group_name);
+ if (!group)
+ die("group not found - %s", group_name);
+
+ c.gid = group->gr_gid;
+ }
+
+ return &c;
+}
+#endif
+
+static void store_pid(const char *path)
+{
+ FILE *f = fopen(path, "w");
+ if (!f)
+ die_errno("cannot open pid file '%s'", path);
+ if (fprintf(f, "%"PRIuMAX"\n", (uintmax_t) getpid()) < 0 || fclose(f) != 0)
+ die_errno("failed to write pid file '%s'", path);
+}
+
+static int serve(struct string_list *listen_addr, int listen_port,
+ struct credentials *cred)
+{
+ struct socketlist socklist = { NULL, 0, 0 };
+
+ socksetup(listen_addr, listen_port, &socklist);
+ if (socklist.nr == 0)
+ die("unable to allocate any listen sockets on port %u",
+ listen_port);
+
+ drop_privileges(cred);
+
+ loginfo("Ready to rumble");
+
+ return service_loop(&socklist);
+}
+
+int main(int argc, char **argv)
+{
+ int listen_port = 0;
+ struct string_list listen_addr = STRING_LIST_INIT_NODUP;
+ int serve_mode = 0, inetd_mode = 0;
+ const char *pid_file = NULL, *user_name = NULL, *group_name = NULL;
+ int detach = 0;
+ struct credentials *cred = NULL;
+ int i;
+
+ git_setup_gettext();
+
+ git_extract_argv0_path(argv[0]);
+
+ for (i = 1; i < argc; i++) {
+ char *arg = argv[i];
+
+ if (starts_with(arg, "--listen=")) {
+ string_list_append(&listen_addr, xstrdup_tolower(arg + 9));
+ continue;
+ }
+ if (starts_with(arg, "--port=")) {
+ char *end;
+ unsigned long n;
+ n = strtoul(arg+7, &end, 0);
+ if (arg[7] && !*end) {
+ listen_port = n;
+ continue;
+ }
+ }
+ if (!strcmp(arg, "--serve")) {
+ serve_mode = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--inetd")) {
+ inetd_mode = 1;
+ log_syslog = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--verbose")) {
+ verbose = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--syslog")) {
+ log_syslog = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--export-all")) {
+ export_all_trees = 1;
+ continue;
+ }
+ if (starts_with(arg, "--access-hook=")) {
+ access_hook = arg + 14;
+ continue;
+ }
+ if (starts_with(arg, "--timeout=")) {
+ timeout = atoi(arg+10);
+ continue;
+ }
+ if (starts_with(arg, "--init-timeout=")) {
+ init_timeout = atoi(arg+15);
+ continue;
+ }
+ if (starts_with(arg, "--max-connections=")) {
+ max_connections = atoi(arg+18);
+ if (max_connections < 0)
+ max_connections = 0; /* unlimited */
+ continue;
+ }
+ if (!strcmp(arg, "--strict-paths")) {
+ strict_paths = 1;
+ continue;
+ }
+ if (starts_with(arg, "--base-path=")) {
+ base_path = arg+12;
+ continue;
+ }
+ if (!strcmp(arg, "--base-path-relaxed")) {
+ base_path_relaxed = 1;
+ continue;
+ }
+ if (starts_with(arg, "--interpolated-path=")) {
+ interpolated_path = arg+20;
+ continue;
+ }
+ if (!strcmp(arg, "--reuseaddr")) {
+ reuseaddr = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--user-path")) {
+ user_path = "";
+ continue;
+ }
+ if (starts_with(arg, "--user-path=")) {
+ user_path = arg + 12;
+ continue;
+ }
+ if (starts_with(arg, "--pid-file=")) {
+ pid_file = arg + 11;
+ continue;
+ }
+ if (!strcmp(arg, "--detach")) {
+ detach = 1;
+ log_syslog = 1;
+ continue;
+ }
+ if (starts_with(arg, "--user=")) {
+ user_name = arg + 7;
+ continue;
+ }
+ if (starts_with(arg, "--group=")) {
+ group_name = arg + 8;
+ continue;
+ }
+ if (starts_with(arg, "--enable=")) {
+ enable_service(arg + 9, 1);
+ continue;
+ }
+ if (starts_with(arg, "--disable=")) {
+ enable_service(arg + 10, 0);
+ continue;
+ }
+ if (starts_with(arg, "--allow-override=")) {
+ make_service_overridable(arg + 17, 1);
+ continue;
+ }
+ if (starts_with(arg, "--forbid-override=")) {
+ make_service_overridable(arg + 18, 0);
+ continue;
+ }
+ if (!strcmp(arg, "--informative-errors")) {
+ informative_errors = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--no-informative-errors")) {
+ informative_errors = 0;
+ continue;
+ }
+ if (!strcmp(arg, "--")) {
+ ok_paths = &argv[i+1];
+ break;
+ } else if (arg[0] != '-') {
+ ok_paths = &argv[i];
+ break;
+ }
+
+ usage(daemon_usage);
+ }
+
+ if (log_syslog) {
+ openlog("git-daemon", LOG_PID, LOG_DAEMON);
+ set_die_routine(daemon_die);
+ } else
+ /* avoid splitting a message in the middle */
+ setvbuf(stderr, NULL, _IOFBF, 4096);
+
+ if (inetd_mode && (detach || group_name || user_name))
+ die("--detach, --user and --group are incompatible with --inetd");
+
+ if (inetd_mode && (listen_port || (listen_addr.nr > 0)))
+ die("--listen= and --port= are incompatible with --inetd");
+ else if (listen_port == 0)
+ listen_port = DEFAULT_GIT_PORT;
+
+ if (group_name && !user_name)
+ die("--group supplied without --user");
+
+ if (user_name)
+ cred = prepare_credentials(user_name, group_name);
+
+ if (strict_paths && (!ok_paths || !*ok_paths))
+ die("option --strict-paths requires a whitelist");
+
+ if (base_path && !is_directory(base_path))
+ die("base-path '%s' does not exist or is not a directory",
+ base_path);
+
+ if (inetd_mode) {
+ if (!freopen("/dev/null", "w", stderr))
+ die_errno("failed to redirect stderr to /dev/null");
+ }
+
+ if (inetd_mode || serve_mode)
+ return execute();
+
+ if (detach) {
+ if (daemonize())
+ die("--detach not supported on this platform");
+ } else
+ sanitize_stdfds();
+
+ if (pid_file)
+ store_pid(pid_file);
+
+ /* prepare argv for serving-processes */
+ cld_argv = xmalloc(sizeof (char *) * (argc + 2));
+ cld_argv[0] = argv[0]; /* git-daemon */
+ cld_argv[1] = "--serve";
+ for (i = 1; i < argc; ++i)
+ cld_argv[i+1] = argv[i];
+ cld_argv[argc+1] = NULL;
+
+ return serve(&listen_addr, listen_port, cred);
+}