X-Git-Url: https://mattmccutchen.net/rsync/rsync.git/blobdiff_plain/ff81e809f46293171a332a2faa320aca57277b4b..973007daac25a8cd64c617fe57f566a037fad179:/clientserver.c

diff --git a/clientserver.c b/clientserver.c
index 3d8b0a18..43d9e541 100644
--- a/clientserver.c
+++ b/clientserver.c
@@ -1,24 +1,29 @@
 /* -*- c-file-style: "linux"; -*-
-   
-   Copyright (C) 1998-2001 by Andrew Tridgell <tridge@samba.org>
-   Copyright (C) 2001 by Martin Pool <mbp@samba.org>
-   
-   This program is free software; you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 2 of the License, or
-   (at your option) any later version.
-   
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-   
-   You should have received a copy of the GNU General Public License
-   along with this program; if not, write to the Free Software
-   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
-*/
-
-/* the socket based protocol for setting up a connection with rsyncd */
+ * 
+ * Copyright (C) 1998-2001 by Andrew Tridgell <tridge@samba.org>
+ * Copyright (C) 2001-2002 by Martin Pool <mbp@samba.org>
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+/**
+ * @file
+ *
+ * The socket based protocol for setting up a connection with
+ * rsyncd.
+ **/
 
 #include "rsync.h"
 
@@ -27,12 +32,22 @@ extern int read_only;
 extern int verbose;
 extern int rsync_port;
 char *auth_user;
-int sanitize_paths = 0;
+extern int sanitize_paths;
 
-/*
+/**
  * Run a client connected to an rsyncd.  The alternative to this
- * function for remote-shell connections is do_cmd.
- */
+ * function for remote-shell connections is do_cmd().
+ *
+ * After negotiating which module to use and reading the server's
+ * motd, this hands over to client_run().  Telling the server the
+ * module will cause it to chroot/setuid/etc.
+ *
+ * Instead of doing a transfer, the client may at this stage instead
+ * get a listing of remote modules and exit.
+ *
+ * @return -1 for error in startup, or the result of client_run().
+ * Either way, it eventually gets passed to exit_cleanup().
+ **/
 int start_socket_client(char *host, char *path, int argc, char *argv[])
 {
 	int fd, i;
@@ -42,9 +57,12 @@ int start_socket_client(char *host, char *path, int argc, char *argv[])
 	char *p, *user=NULL;
 	extern int remote_version;
 	extern int am_sender;
-	extern struct in_addr socket_address;
 	extern char *shell_cmd;
-
+	extern int list_only;
+	extern int kludge_around_eof;
+	extern char *bind_address;
+	extern int default_af_hint;
+       
 	if (argc == 0 && !am_sender) {
 		extern int list_only;
 		list_only = 1;
@@ -57,7 +75,7 @@ int start_socket_client(char *host, char *path, int argc, char *argv[])
          * See http://lists.samba.org/pipermail/rsync/2000-September/002744.html
          */
         if (shell_cmd) {
-                rprintf(FERROR, "WARNING: --rsh or -e option ignored when "
+                rprintf(FINFO, "WARNING: --rsh or -e option ignored when "
                         "connecting to rsync daemon\n");
                 /* continue */
         }
@@ -77,7 +95,15 @@ int start_socket_client(char *host, char *path, int argc, char *argv[])
 	if (!user) user = getenv("USER");
 	if (!user) user = getenv("LOGNAME");
 
-	fd = open_socket_out(host, rsync_port, &socket_address);
+	if (verbose >= 2) {
+		/* FIXME: If we're going to use a socket program for
+		 * testing, then this message is wrong.  We need to
+		 * say something like "(except really using %s)" */
+		rprintf(FINFO, "opening tcp connection to %s port %d\n",
+			host, rsync_port);
+	}
+	fd = open_socket_out_wrapped (host, rsync_port, bind_address,
+				      default_af_hint);
 	if (fd == -1) {
 		exit_cleanup(RERR_SOCKETIO);
 	}
@@ -94,10 +120,14 @@ int start_socket_client(char *host, char *path, int argc, char *argv[])
 	io_printf(fd,"@RSYNCD: %d\n", PROTOCOL_VERSION);
 
 	if (!read_line(fd, line, sizeof(line)-1)) {
+		rprintf(FERROR, "rsync: did not see server greeting\n");
 		return -1;
 	}
 
 	if (sscanf(line,"@RSYNCD: %d", &remote_version) != 1) {
+		/* note that read_line strips of \n or \r */
+		rprintf(FERROR, "rsync: server sent \"%s\" rather than greeting\n",
+			line);
 		return -1;
 	}
 
@@ -106,8 +136,13 @@ int start_socket_client(char *host, char *path, int argc, char *argv[])
 	io_printf(fd,"%s\n",path);
 	if (p) *p = '/';
 
+	/* Old servers may just drop the connection here,
+	 rather than sending a proper EXIT command.  Yuck. */
+	kludge_around_eof = list_only && (remote_version < 25);
+
 	while (1) {
 		if (!read_line(fd, line, sizeof(line)-1)) {
+			rprintf(FERROR, "rsync: didn't get server startup line\n");
 			return -1;
 		}
 
@@ -117,8 +152,25 @@ int start_socket_client(char *host, char *path, int argc, char *argv[])
 		}
 
 		if (strcmp(line,"@RSYNCD: OK") == 0) break;
-		rprintf(FINFO,"%s\n", line);
+
+		if (strcmp(line,"@RSYNCD: EXIT") == 0) {
+			/* This is sent by recent versions of the
+			 * server to terminate the listing of modules.
+			 * We don't want to go on and transfer
+			 * anything; just exit. */
+			exit(0);
+		}
+
+		if (strncmp(line, "@ERROR", 6) == 0) {
+			rprintf(FERROR,"%s\n", line);
+			/* This is always fatal; the server will now
+			 * close the socket. */
+			return RERR_STARTCLIENT;
+		} else {
+			rprintf(FINFO,"%s\n", line);
+		}
 	}
+	kludge_around_eof = False;
 
 	for (i=0;i<sargc;i++) {
 		io_printf(fd,"%s\n", sargs[i]);
@@ -157,9 +209,9 @@ static int rsync_module(int fd, int i)
 
 	if (!allow_access(addr, host, lp_hosts_allow(i), lp_hosts_deny(i))) {
 		rprintf(FERROR,"rsync denied on module %s from %s (%s)\n",
-			name, client_name(fd), client_addr(fd));
+			name, host, addr);
 		io_printf(fd,"@ERROR: access denied to %s from %s (%s)\n",
-			  name, client_name(fd), client_addr(fd));
+			  name, host, addr);
 		return -1;
 	}
 
@@ -194,7 +246,7 @@ static int rsync_module(int fd, int i)
 	if (am_root) {
 		p = lp_uid(i);
 		if (!name_to_uid(p, &uid)) {
-			if (!isdigit(*p)) {
+			if (!isdigit(* (unsigned char *) p)) {
 				rprintf(FERROR,"Invalid uid %s\n", p);
 				io_printf(fd,"@ERROR: invalid uid %s\n", p);
 				return -1;
@@ -204,7 +256,7 @@ static int rsync_module(int fd, int i)
 
 		p = lp_gid(i);
 		if (!name_to_gid(p, &gid)) {
-			if (!isdigit(*p)) {
+			if (!isdigit(* (unsigned char *) p)) {
 				rprintf(FERROR,"Invalid gid %s\n", p);
 				io_printf(fd,"@ERROR: invalid gid %s\n", p);
 				return -1;
@@ -235,6 +287,18 @@ static int rsync_module(int fd, int i)
 	log_init();
 
 	if (use_chroot) {
+		/*
+		 * XXX: The 'use chroot' flag is a fairly reliable
+		 * source of confusion, because it fails under two
+		 * important circumstances: running as non-root,
+		 * running on Win32 (or possibly others).  On the
+		 * other hand, if you are running as root, then it
+		 * might be better to always use chroot.
+		 *
+		 * So, perhaps if we can't chroot we should just issue
+		 * a warning, unless a "require chroot" flag is set,
+		 * in which case we fail.
+		 */
 		if (chroot(lp_path(i))) {
 			rsyserr(FERROR, errno, "chroot %s failed", lp_path(i));
 			io_printf(fd,"@ERROR: chroot failed\n");
@@ -257,14 +321,34 @@ static int rsync_module(int fd, int i)
 	}
 
 	if (am_root) {
+#ifdef HAVE_SETGROUPS
+		/* Get rid of any supplementary groups this process
+		 * might have inheristed. */
+		if (setgroups(0, NULL)) {
+			rsyserr(FERROR, errno, "setgroups failed");
+			io_printf(fd, "@ERROR: setgroups failed\n");
+			return -1;
+		}
+#endif
+
+		/* XXXX: You could argue that if the daemon is started
+		 * by a non-root user and they explicitly specify a
+		 * gid, then we should try to change to that gid --
+		 * this could be possible if it's already in their
+		 * supplementary groups. */
+
+		/* TODO: Perhaps we need to document that if rsyncd is
+		 * started by somebody other than root it will inherit
+		 * all their supplementary groups. */
+
 		if (setgid(gid)) {
-			rsyserr(FERROR, errno, "setgid %d failed", gid);
+			rsyserr(FERROR, errno, "setgid %d failed", (int) gid);
 			io_printf(fd,"@ERROR: setgid failed\n");
 			return -1;
 		}
 
 		if (setuid(uid)) {
-			rsyserr(FERROR, errno, "setuid %d failed", uid);
+			rsyserr(FERROR, errno, "setuid %d failed", (int) uid);
 			io_printf(fd,"@ERROR: setuid failed\n");
 			return -1;
 		}
@@ -377,10 +461,14 @@ static void send_listing(int fd)
 {
 	int n = lp_numservices();
 	int i;
-	
+	extern int remote_version;
+
 	for (i=0;i<n;i++)
 		if (lp_list(i))
 		    io_printf(fd, "%-15s\t%s\n", lp_name(i), lp_comment(i));
+
+	if (remote_version >= 25)
+		io_printf(fd,"@RSYNCD: EXIT\n");
 }
 
 /* this is called when a socket connection is established to a client
@@ -460,6 +548,7 @@ int daemon_main(void)
 	extern char *config_file;
 	extern int orig_umask;
 	char *pid_file;
+	extern int no_detach;
 
 	if (is_a_socket(STDIN_FILENO)) {
 		int i;
@@ -475,7 +564,8 @@ int daemon_main(void)
 		return start_daemon(STDIN_FILENO);
 	}
 
-	become_daemon();
+	if (!no_detach)
+	    become_daemon();
 
 	if (!lp_load(config_file, 1)) {
 		exit_cleanup(RERR_SYNTAX);
@@ -483,10 +573,12 @@ int daemon_main(void)
 
 	log_init();
 
-	rprintf(FINFO, "rsyncd version %s starting, listening on port %d\n", VERSION,
+	rprintf(FINFO, "rsyncd version %s starting, listening on port %d\n",
+		RSYNC_VERSION,
                 rsync_port);
         /* TODO: If listening on a particular address, then show that
-         * address too. */
+         * address too.  In fact, why not just do inet_ntop on the
+         * local address??? */
 
 	if (((pid_file = lp_pid_file()) != NULL) && (*pid_file != '\0')) {
 		char pidbuf[16];
@@ -499,7 +591,7 @@ int daemon_main(void)
 		    rsyserr(FLOG, errno, "failed to create pid file %s", pid_file);
 		    exit_cleanup(RERR_FILEIO);
 		}
-		slprintf(pidbuf, sizeof(pidbuf), "%d\n", pid);
+		snprintf(pidbuf, sizeof(pidbuf), "%d\n", pid);
 		write(fd, pidbuf, strlen(pidbuf));
 		close(fd);
 	}