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-rw-r--r--daemon.c1181
1 files changed, 1181 insertions, 0 deletions
diff --git a/daemon.c b/daemon.c
new file mode 100644
index 0000000000..a3f2ac1d81
--- /dev/null
+++ b/daemon.c
@@ -0,0 +1,1181 @@
+#include "cache.h"
+#include "pkt-line.h"
+#include "exec_cmd.h"
+#include "interpolate.h"
+
+#include <syslog.h>
+
+#ifndef HOST_NAME_MAX
+#define HOST_NAME_MAX 256
+#endif
+
+static int log_syslog;
+static int verbose;
+static int reuseaddr;
+
+static const char daemon_usage[] =
+"git-daemon [--verbose] [--syslog] [--export-all]\n"
+" [--timeout=n] [--init-timeout=n] [--strict-paths]\n"
+" [--base-path=path] [--user-path | --user-path=path]\n"
+" [--interpolated-path=path]\n"
+" [--reuseaddr] [--detach] [--pid-file=file]\n"
+" [--[enable|disable|allow-override|forbid-override]=service]\n"
+" [--inetd | [--listen=host_or_ipaddr] [--port=n]\n"
+" [--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;
+
+/* 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 table for now. Ugh.
+ * Feel free to make dynamic as needed.
+ */
+#define INTERP_SLOT_HOST (0)
+#define INTERP_SLOT_CANON_HOST (1)
+#define INTERP_SLOT_IP (2)
+#define INTERP_SLOT_PORT (3)
+#define INTERP_SLOT_DIR (4)
+#define INTERP_SLOT_PERCENT (5)
+
+static struct interp interp_table[] = {
+ { "%H", 0},
+ { "%CH", 0},
+ { "%IP", 0},
+ { "%P", 0},
+ { "%D", 0},
+ { "%%", 0},
+};
+
+
+static void logreport(int priority, const char *err, va_list params)
+{
+ /* We should do a single write so that it is atomic and output
+ * of several processes do not get intermingled. */
+ char buf[1024];
+ int buflen;
+ int maxlen, msglen;
+
+ /* sizeof(buf) should be big enough for "[pid] \n" */
+ buflen = snprintf(buf, sizeof(buf), "[%ld] ", (long) getpid());
+
+ maxlen = sizeof(buf) - buflen - 1; /* -1 for our own LF */
+ msglen = vsnprintf(buf + buflen, maxlen, err, params);
+
+ if (log_syslog) {
+ syslog(priority, "%s", buf);
+ return;
+ }
+
+ /* maxlen counted our own LF but also counts space given to
+ * vsnprintf for the terminating NUL. We want to make sure that
+ * we have space for our own LF and NUL after the "meat" of the
+ * message, so truncate it at maxlen - 1.
+ */
+ if (msglen > maxlen - 1)
+ msglen = maxlen - 1;
+ else if (msglen < 0)
+ msglen = 0; /* Protect against weird return values. */
+ buflen += msglen;
+
+ buf[buflen++] = '\n';
+ buf[buflen] = '\0';
+
+ write_in_full(2, buf, buflen);
+}
+
+static void logerror(const char *err, ...)
+{
+ va_list params;
+ va_start(params, err);
+ logreport(LOG_ERR, err, params);
+ va_end(params);
+}
+
+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 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;
+ ndot = 0;
+ }
+ }
+}
+
+static char *path_ok(struct interp *itable)
+{
+ static char rpath[PATH_MAX];
+ static char interp_path[PATH_MAX];
+ char *path;
+ char *dir;
+
+ dir = itable[INTERP_SLOT_DIR].value;
+
+ 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 (interpolated_path && saw_extended_args) {
+ if (*dir != '/') {
+ /* Allow only absolute */
+ logerror("'%s': Non-absolute path denied (interpolated-path active)", dir);
+ return NULL;
+ }
+
+ interpolate(interp_path, PATH_MAX, interpolated_path,
+ interp_table, ARRAY_SIZE(interp_table));
+ 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) {
+ 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 <= 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)
+{
+ if (!prefixcmp(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 run_service(struct interp *itable, struct daemon_service *service)
+{
+ const char *path;
+ int enabled = service->enabled;
+
+ loginfo("Request %s for '%s'",
+ service->name,
+ itable[INTERP_SLOT_DIR].value);
+
+ if (!enabled && !service->overridable) {
+ logerror("'%s': service not enabled.", service->name);
+ errno = EACCES;
+ return -1;
+ }
+
+ if (!(path = path_ok(itable)))
+ return -1;
+
+ /*
+ * 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 -1;
+ }
+
+ if (service->overridable) {
+ service_looking_at = service;
+ service_enabled = -1;
+ git_config(git_daemon_config);
+ if (0 <= service_enabled)
+ enabled = service_enabled;
+ }
+ if (!enabled) {
+ logerror("'%s': service not enabled for '%s'",
+ service->name, path);
+ errno = EACCES;
+ return -1;
+ }
+
+ /*
+ * We'll ignore SIGTERM from now on, we have a
+ * good client.
+ */
+ signal(SIGTERM, SIG_IGN);
+
+ return service->fn();
+}
+
+static int upload_pack(void)
+{
+ /* Timeout as string */
+ char timeout_buf[64];
+
+ snprintf(timeout_buf, sizeof timeout_buf, "--timeout=%u", timeout);
+
+ /* git-upload-pack only ever reads stuff, so this is safe */
+ execl_git_cmd("upload-pack", "--strict", timeout_buf, ".", NULL);
+ return -1;
+}
+
+static int upload_archive(void)
+{
+ execl_git_cmd("upload-archive", ".", NULL);
+ return -1;
+}
+
+static int receive_pack(void)
+{
+ execl_git_cmd("receive-pack", ".", NULL);
+ return -1;
+}
+
+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);
+}
+
+/*
+ * Separate the "extra args" information as supplied by the client connection.
+ * Any resulting data is squirreled away in the given interpolation table.
+ */
+static void parse_extra_args(struct interp *table, char *extra_args, int buflen)
+{
+ char *val;
+ int vallen;
+ char *end = extra_args + buflen;
+
+ while (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 = val;
+ char *port = strrchr(host, ':');
+ if (port) {
+ *port = 0;
+ port++;
+ interp_set_entry(table, INTERP_SLOT_PORT, port);
+ }
+ interp_set_entry(table, INTERP_SLOT_HOST, host);
+ }
+
+ /* On to the next one */
+ extra_args = val + vallen;
+ }
+ }
+}
+
+static void fill_in_extra_table_entries(struct interp *itable)
+{
+ char *hp;
+
+ /*
+ * Replace literal host with lowercase-ized hostname.
+ */
+ hp = interp_table[INTERP_SLOT_HOST].value;
+ if (!hp)
+ return;
+ for ( ; *hp; hp++)
+ *hp = tolower(*hp);
+
+ /*
+ * Locate canonical hostname and its IP address.
+ */
+#ifndef NO_IPV6
+ {
+ struct addrinfo hints;
+ struct addrinfo *ai, *ai0;
+ int gai;
+ static char addrbuf[HOST_NAME_MAX + 1];
+
+ memset(&hints, 0, sizeof(hints));
+ hints.ai_flags = AI_CANONNAME;
+
+ gai = getaddrinfo(interp_table[INTERP_SLOT_HOST].value, 0, &hints, &ai0);
+ if (!gai) {
+ for (ai = ai0; ai; ai = ai->ai_next) {
+ struct sockaddr_in *sin_addr = (void *)ai->ai_addr;
+
+ inet_ntop(AF_INET, &sin_addr->sin_addr,
+ addrbuf, sizeof(addrbuf));
+ interp_set_entry(interp_table,
+ INTERP_SLOT_CANON_HOST, ai->ai_canonname);
+ interp_set_entry(interp_table,
+ INTERP_SLOT_IP, addrbuf);
+ break;
+ }
+ freeaddrinfo(ai0);
+ }
+ }
+#else
+ {
+ struct hostent *hent;
+ struct sockaddr_in sa;
+ char **ap;
+ static char addrbuf[HOST_NAME_MAX + 1];
+
+ hent = gethostbyname(interp_table[INTERP_SLOT_HOST].value);
+
+ 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));
+
+ interp_set_entry(interp_table, INTERP_SLOT_CANON_HOST, hent->h_name);
+ interp_set_entry(interp_table, INTERP_SLOT_IP, addrbuf);
+ }
+#endif
+}
+
+
+static int execute(struct sockaddr *addr)
+{
+ static char line[1000];
+ int pktlen, len, i;
+
+ 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);
+ }
+
+ 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;
+ pktlen--;
+ }
+
+ /*
+ * Initialize the path interpolation table for this connection.
+ */
+ interp_clear_table(interp_table, ARRAY_SIZE(interp_table));
+ interp_set_entry(interp_table, INTERP_SLOT_PERCENT, "%");
+
+ if (len != pktlen) {
+ parse_extra_args(interp_table, line + len + 1, pktlen - len - 1);
+ fill_in_extra_table_entries(interp_table);
+ }
+
+ for (i = 0; i < ARRAY_SIZE(daemon_service); i++) {
+ struct daemon_service *s = &(daemon_service[i]);
+ int namelen = strlen(s->name);
+ if (!prefixcmp(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.
+ */
+ interp_set_entry(interp_table,
+ INTERP_SLOT_DIR, line + namelen + 5);
+ return run_service(interp_table, s);
+ }
+ }
+
+ logerror("Protocol error: '%s'", line);
+ return -1;
+}
+
+
+/*
+ * We count spawned/reaped separately, just to avoid any
+ * races when updating them from signals. The SIGCHLD handler
+ * will only update children_reaped, and the fork logic will
+ * only update children_spawned.
+ *
+ * MAX_CHILDREN should be a power-of-two to make the modulus
+ * operation cheap. It should also be at least twice
+ * the maximum number of connections we will ever allow.
+ */
+#define MAX_CHILDREN 128
+
+static int max_connections = 25;
+
+/* These are updated by the signal handler */
+static volatile unsigned int children_reaped;
+static pid_t dead_child[MAX_CHILDREN];
+
+/* These are updated by the main loop */
+static unsigned int children_spawned;
+static unsigned int children_deleted;
+
+static struct child {
+ pid_t pid;
+ int addrlen;
+ struct sockaddr_storage address;
+} live_child[MAX_CHILDREN];
+
+static void add_child(int idx, pid_t pid, struct sockaddr *addr, int addrlen)
+{
+ live_child[idx].pid = pid;
+ live_child[idx].addrlen = addrlen;
+ memcpy(&live_child[idx].address, addr, addrlen);
+}
+
+/*
+ * Walk from "deleted" to "spawned", and remove child "pid".
+ *
+ * We move everything up by one, since the new "deleted" will
+ * be one higher.
+ */
+static void remove_child(pid_t pid, unsigned deleted, unsigned spawned)
+{
+ struct child n;
+
+ deleted %= MAX_CHILDREN;
+ spawned %= MAX_CHILDREN;
+ if (live_child[deleted].pid == pid) {
+ live_child[deleted].pid = -1;
+ return;
+ }
+ n = live_child[deleted];
+ for (;;) {
+ struct child m;
+ deleted = (deleted + 1) % MAX_CHILDREN;
+ if (deleted == spawned)
+ die("could not find dead child %d\n", pid);
+ m = live_child[deleted];
+ live_child[deleted] = n;
+ if (m.pid == pid)
+ return;
+ n = m;
+ }
+}
+
+/*
+ * This gets called if the number of connections grows
+ * past "max_connections".
+ *
+ * We _should_ start off by searching for connections
+ * from the same IP, and if there is some address wth
+ * multiple connections, we should kill that first.
+ *
+ * As it is, we just "randomly" kill 25% of the connections,
+ * and our pseudo-random generator sucks too. I have no
+ * shame.
+ *
+ * Really, this is just a place-holder for a _real_ algorithm.
+ */
+static void kill_some_children(int signo, unsigned start, unsigned stop)
+{
+ start %= MAX_CHILDREN;
+ stop %= MAX_CHILDREN;
+ while (start != stop) {
+ if (!(start & 3))
+ kill(live_child[start].pid, signo);
+ start = (start + 1) % MAX_CHILDREN;
+ }
+}
+
+static void check_max_connections(void)
+{
+ for (;;) {
+ int active;
+ unsigned spawned, reaped, deleted;
+
+ spawned = children_spawned;
+ reaped = children_reaped;
+ deleted = children_deleted;
+
+ while (deleted < reaped) {
+ pid_t pid = dead_child[deleted % MAX_CHILDREN];
+ remove_child(pid, deleted, spawned);
+ deleted++;
+ }
+ children_deleted = deleted;
+
+ active = spawned - deleted;
+ if (active <= max_connections)
+ break;
+
+ /* Kill some unstarted connections with SIGTERM */
+ kill_some_children(SIGTERM, deleted, spawned);
+ if (active <= max_connections << 1)
+ break;
+
+ /* If the SIGTERM thing isn't helping use SIGKILL */
+ kill_some_children(SIGKILL, deleted, spawned);
+ sleep(1);
+ }
+}
+
+static void handle(int incoming, struct sockaddr *addr, int addrlen)
+{
+ pid_t pid = fork();
+
+ if (pid) {
+ unsigned idx;
+
+ close(incoming);
+ if (pid < 0)
+ return;
+
+ idx = children_spawned % MAX_CHILDREN;
+ children_spawned++;
+ add_child(idx, pid, addr, addrlen);
+
+ check_max_connections();
+ return;
+ }
+
+ dup2(incoming, 0);
+ dup2(incoming, 1);
+ close(incoming);
+
+ exit(execute(addr));
+}
+
+static void child_handler(int signo)
+{
+ for (;;) {
+ int status;
+ pid_t pid = waitpid(-1, &status, WNOHANG);
+
+ if (pid > 0) {
+ unsigned reaped = children_reaped;
+ dead_child[reaped % MAX_CHILDREN] = pid;
+ children_reaped = reaped + 1;
+ /* XXX: Custom logging, since we don't wanna getpid() */
+ if (verbose) {
+ const char *dead = "";
+ if (!WIFEXITED(status) || WEXITSTATUS(status) > 0)
+ dead = " (with error)";
+ if (log_syslog)
+ syslog(LOG_INFO, "[%d] Disconnected%s", pid, dead);
+ else
+ fprintf(stderr, "[%d] Disconnected%s\n", pid, dead);
+ }
+ continue;
+ }
+ break;
+ }
+}
+
+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(char *listen_addr, int listen_port, int **socklist_p)
+{
+ int socknum = 0, *socklist = NULL;
+ 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)
+ die("getaddrinfo() failed: %s\n", gai_strerror(gai));
+
+ 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) {
+ error("too large socket descriptor.");
+ 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)) {
+ close(sockfd);
+ continue;
+ }
+
+ if (bind(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
+ close(sockfd);
+ continue; /* not fatal */
+ }
+ if (listen(sockfd, 5) < 0) {
+ close(sockfd);
+ continue; /* not fatal */
+ }
+
+ flags = fcntl(sockfd, F_GETFD, 0);
+ if (flags >= 0)
+ fcntl(sockfd, F_SETFD, flags | FD_CLOEXEC);
+
+ socklist = xrealloc(socklist, sizeof(int) * (socknum + 1));
+ socklist[socknum++] = sockfd;
+
+ if (maxfd < sockfd)
+ maxfd = sockfd;
+ }
+
+ freeaddrinfo(ai0);
+
+ *socklist_p = socklist;
+ return socknum;
+}
+
+#else /* NO_IPV6 */
+
+static int socksetup(char *listen_addr, int listen_port, int **socklist_p)
+{
+ 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)) {
+ 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;
+ }
+
+ flags = fcntl(sockfd, F_GETFD, 0);
+ if (flags >= 0)
+ fcntl(sockfd, F_SETFD, flags | FD_CLOEXEC);
+
+ *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;
+
+ if (poll(pfd, socknum, -1) < 0) {
+ if (errno != EINTR) {
+ error("poll failed, resuming: %s",
+ strerror(errno));
+ sleep(1);
+ }
+ continue;
+ }
+
+ for (i = 0; i < socknum; i++) {
+ if (pfd[i].revents & POLLIN) {
+ struct sockaddr_storage ss;
+ unsigned int sslen = sizeof(ss);
+ int incoming = accept(pfd[i].fd, (struct sockaddr *)&ss, &sslen);
+ if (incoming < 0) {
+ switch (errno) {
+ case EAGAIN:
+ case EINTR:
+ case ECONNABORTED:
+ continue;
+ default:
+ die("accept returned %s", strerror(errno));
+ }
+ }
+ handle(incoming, (struct sockaddr *)&ss, sslen);
+ }
+ }
+ }
+}
+
+/* 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));
+ if (fprintf(f, "%d\n", getpid()) < 0 || fclose(f) != 0)
+ die("failed to write pid file %s: %s", path, strerror(errno));
+}
+
+static int serve(char *listen_addr, int listen_port, struct passwd *pass, gid_t gid)
+{
+ int socknum, *socklist;
+
+ socknum = socksetup(listen_addr, listen_port, &socklist);
+ if (socknum == 0)
+ die("unable to allocate any listen sockets on host %s port %u",
+ listen_addr, listen_port);
+
+ if (pass && gid &&
+ (initgroups(pass->pw_name, gid) || setgid (gid) ||
+ setuid(pass->pw_uid)))
+ die("cannot drop privileges");
+
+ return service_loop(socknum, socklist);
+}
+
+int main(int argc, char **argv)
+{
+ int listen_port = 0;
+ char *listen_addr = NULL;
+ int inetd_mode = 0;
+ const char *pid_file = NULL, *user_name = NULL, *group_name = NULL;
+ int detach = 0;
+ struct passwd *pass = NULL;
+ struct group *group;
+ gid_t gid = 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 (!prefixcmp(arg, "--listen=")) {
+ char *p = arg + 9;
+ char *ph = listen_addr = xmalloc(strlen(arg + 9) + 1);
+ while (*p)
+ *ph++ = tolower(*p++);
+ *ph = 0;
+ continue;
+ }
+ if (!prefixcmp(arg, "--port=")) {
+ char *end;
+ unsigned long n;
+ n = strtoul(arg+7, &end, 0);
+ if (arg[7] && !*end) {
+ listen_port = n;
+ 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 (!prefixcmp(arg, "--timeout=")) {
+ timeout = atoi(arg+10);
+ continue;
+ }
+ if (!prefixcmp(arg, "--init-timeout=")) {
+ init_timeout = atoi(arg+15);
+ continue;
+ }
+ if (!strcmp(arg, "--strict-paths")) {
+ strict_paths = 1;
+ continue;
+ }
+ if (!prefixcmp(arg, "--base-path=")) {
+ base_path = arg+12;
+ continue;
+ }
+ if (!prefixcmp(arg, "--interpolated-path=")) {
+ interpolated_path = arg+20;
+ continue;
+ }
+ if (!strcmp(arg, "--reuseaddr")) {
+ reuseaddr = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--user-path")) {
+ user_path = "";
+ continue;
+ }
+ if (!prefixcmp(arg, "--user-path=")) {
+ user_path = arg + 12;
+ continue;
+ }
+ if (!prefixcmp(arg, "--pid-file=")) {
+ pid_file = arg + 11;
+ continue;
+ }
+ if (!strcmp(arg, "--detach")) {
+ detach = 1;
+ log_syslog = 1;
+ continue;
+ }
+ if (!prefixcmp(arg, "--user=")) {
+ user_name = arg + 7;
+ continue;
+ }
+ if (!prefixcmp(arg, "--group=")) {
+ group_name = arg + 8;
+ continue;
+ }
+ if (!prefixcmp(arg, "--enable=")) {
+ enable_service(arg + 9, 1);
+ continue;
+ }
+ if (!prefixcmp(arg, "--disable=")) {
+ enable_service(arg + 10, 0);
+ continue;
+ }
+ if (!prefixcmp(arg, "--allow-override=")) {
+ make_service_overridable(arg + 17, 1);
+ continue;
+ }
+ if (!prefixcmp(arg, "--forbid-override=")) {
+ make_service_overridable(arg + 18, 0);
+ continue;
+ }
+ if (!strcmp(arg, "--")) {
+ ok_paths = &argv[i+1];
+ break;
+ } else if (arg[0] != '-') {
+ ok_paths = &argv[i];
+ break;
+ }
+
+ usage(daemon_usage);
+ }
+
+ if (inetd_mode && (group_name || user_name))
+ die("--user and --group are incompatible with --inetd");
+
+ if (inetd_mode && (listen_port || listen_addr))
+ 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) {
+ pass = getpwnam(user_name);
+ if (!pass)
+ die("user not found - %s", user_name);
+
+ if (!group_name)
+ gid = pass->pw_gid;
+ else {
+ group = getgrnam(group_name);
+ if (!group)
+ die("group not found - %s", group_name);
+
+ gid = group->gr_gid;
+ }
+ }
+
+ 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) {
+ 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(listen_addr, listen_port, pass, gid);
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-18 20:32:13 +0000