Teach -f <file> option to builtin-grep.
[gitweb.git] / daemon.c
index bd278b01c11ed831623e3c6db111f53c2e08d050..776749e3432fca916981d73d04a1fa19ed3d88b8 100644 (file)
--- a/daemon.c
+++ b/daemon.c
@@ -1,27 +1,42 @@
-#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]\n"
-"           [--timeout=n] [--init-timeout=n] [directory...]";
+"           [--timeout=n] [--init-timeout=n] [--strict-paths]\n"
+"           [--base-path=path] [--user-path | --user-path=path]\n"
+"           [--reuseaddr] [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 char *user_path = NULL;
+
 /* Timeout, and initial timeout */
 static unsigned int timeout = 0;
 static unsigned int init_timeout = 0;
@@ -80,113 +95,159 @@ static void loginfo(const char *err, ...)
        va_end(params);
 }
 
-static int path_ok(const char *dir)
+static int avoid_alias(char *p)
 {
-       const char *p = dir;
-       char **pp;
        int sl, ndot;
 
-       /* The pathname here should be an absolute path. */
-       if ( *p++ != '/' )
-               return 0;
-
-       sl = 1;  ndot = 0;
-
-       for (;;) {
-               if ( *p == '.' ) {
-                       ndot++;
-               } else if ( *p == '\0' ) {
-                       /* Reject "." and ".." at the end of the path */
-                       if ( sl && ndot > 0 && ndot < 3 )
-                               return 0;
-
-                       /* Otherwise OK */
-                       break;
-               } else if ( *p == '/' ) {
-                       /* Refuse "", "." or ".." */
-                       if ( sl && ndot < 3 )
+       /* 
+        * 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;
-               } else {
-                       sl = ndot = 0;
                }
-               p++;
        }
+}
 
-       if ( ok_paths && *ok_paths ) {
-               int ok = 0;
-               int dirlen = strlen(dir);
+static char *path_ok(char *dir)
+{
+       static char rpath[PATH_MAX];
+       char *path;
 
-               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 (avoid_alias(dir)) {
+               logerror("'%s': aliased", dir);
+               return NULL;
+       }
 
-               if ( !ok )
-                       return 0; /* Path not in whitelist */
+       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;
+               }
        }
 
-       return 1;               /* Path acceptable */
-}
+       path = enter_repo(dir, strict_paths);
 
-static int set_dir(const char *dir)
-{
-       if (!path_ok(dir)) {
-               errno = EACCES;
-               return -1;
+       if (!path) {
+               logerror("'%s': unable to chdir or not a git archive", dir);
+               return NULL;
        }
 
-       if ( chdir(dir) )
-               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.
-        */
-       if (!export_all_trees && access("git-daemon-export-ok", F_OK)) {
-               errno = EACCES;
-               return -1;
+       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;
+               }
        }
-
-       if (access("objects/", X_OK) || access("HEAD", R_OK)) {
-               errno = EINVAL;
-               return -1;
+       else {
+               /* be backwards compatible */
+               if (!strict_paths)
+                       return path;
        }
 
-       /* If all this passed, we're OK */
-       return 0;
+       logerror("'%s': not in whitelist", path);
+       return NULL;            /* Fallthrough. Deny by default */
 }
 
 static int upload(char *dir)
 {
-       /* Try paths in this order */
-       static const char *paths[] = { "%s", "%s/.git", "%s.git", "%s.git/.git", NULL };
-       const char **pp;
-       /* Enough for the longest path above including final null */
-       int buflen = strlen(dir)+10;
-       char *dirbuf = xmalloc(buflen);
        /* Timeout as string */
        char timeout_buf[64];
+       const char *path;
 
        loginfo("Request for '%s'", dir);
 
-       for ( pp = paths ; *pp ; pp++ ) {
-               snprintf(dirbuf, buflen, *pp, dir);
-               if ( !set_dir(dirbuf) )
-                       break;
-       }
+       if (!(path = path_ok(dir)))
+               return -1;
 
-       if ( !*pp ) {
-               logerror("Cannot set directory '%s': %s", dir, strerror(errno));
+       /*
+        * 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;
        }
 
@@ -199,7 +260,7 @@ static int upload(char *dir)
        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", "--strict", timeout_buf, ".", NULL);
+       execl_git_cmd("upload-pack", "--strict", timeout_buf, ".", NULL);
        return -1;
 }
 
@@ -215,7 +276,7 @@ static int execute(void)
        if (len && line[len-1] == '\n')
                line[--len] = 0;
 
-       if (!strncmp("git-upload-pack /", line, 17))
+       if (!strncmp("git-upload-pack ", line, 16))
                return upload(line+16);
 
        logerror("Protocol error: '%s'", line);
@@ -375,6 +436,7 @@ static void handle(int incoming, struct sockaddr *addr, int addrlen)
                inet_ntop(AF_INET, &sin_addr->sin_addr, addrbuf, sizeof(addrbuf));
                port = sin_addr->sin_port;
 
+#ifndef NO_IPV6
        } else if (addr->sa_family == AF_INET6) {
                struct sockaddr_in6 *sin6_addr = (void *) addr;
 
@@ -384,6 +446,7 @@ static void handle(int incoming, struct sockaddr *addr, int addrlen)
                strcat(buf, "]");
 
                port = sin6_addr->sin6_port;
+#endif
        }
        loginfo("Connection from %s:%d", addrbuf, port);
 
@@ -416,16 +479,26 @@ static void child_handler(int signo)
        }
 }
 
-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));
@@ -438,8 +511,6 @@ static int serve(int port)
        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;
@@ -462,6 +533,11 @@ static int serve(int port)
                }
 #endif
 
+               if (set_reuse_addr(sockfd)) {
+                       close(sockfd);
+                       continue;
+               }
+
                if (bind(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
                        close(sockfd);
                        continue;       /* not fatal */
@@ -478,23 +554,74 @@ static int serve(int port)
                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);
                        }
@@ -502,12 +629,10 @@ static int serve(int port)
                }
 
                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:
@@ -524,6 +649,17 @@ static int serve(int port)
        }
 }
 
+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;
@@ -544,6 +680,7 @@ int main(int argc, char **argv)
                }
                if (!strcmp(arg, "--inetd")) {
                        inetd_mode = 1;
+                       log_syslog = 1;
                        continue;
                }
                if (!strcmp(arg, "--verbose")) {
@@ -552,7 +689,6 @@ int main(int argc, char **argv)
                }
                if (!strcmp(arg, "--syslog")) {
                        log_syslog = 1;
-                       openlog("git-daemon", 0, LOG_DAEMON);
                        continue;
                }
                if (!strcmp(arg, "--export-all")) {
@@ -561,9 +697,31 @@ int main(int argc, char **argv)
                }
                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 (!strcmp(arg, "--")) {
                        ok_paths = &argv[i+1];
@@ -576,6 +734,17 @@ int main(int argc, char **argv)
                usage(daemon_usage);
        }
 
+       if (log_syslog)
+               openlog("git-daemon", 0, LOG_DAEMON);
+
+       if (strict_paths && (!ok_paths || !*ok_paths)) {
+               if (!inetd_mode)
+                       die("git-daemon: option --strict-paths requires a whitelist");
+
+               logerror("option --strict-paths requires a whitelist");
+               exit (1);
+       }
+
        if (inetd_mode) {
                fclose(stderr); //FIXME: workaround
                return execute();