X-Git-Url: https://mattmccutchen.net/rsync/rsync.git/blobdiff_plain/554e0a8dd0079cd8d28dbb30ffd90010f2f97933..c120ff37f549e50732948ee236d5680b1e7158e9:/clientserver.c diff --git a/clientserver.c b/clientserver.c index 8c558075..8a26ed5a 100644 --- a/clientserver.c +++ b/clientserver.c @@ -1,22 +1,29 @@ -/* - Copyright (C) Andrew Tridgell 1998 - - 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 wit rsyncd */ +/* -*- c-file-style: "linux"; -*- + * + * Copyright (C) 1998-2001 by Andrew Tridgell + * Copyright (C) 2001-2002 by Martin Pool + * + * 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" @@ -25,21 +32,35 @@ extern int read_only; extern int verbose; extern int rsync_port; char *auth_user; -int sanitize_paths = 0; - +extern int sanitize_paths; +extern int filesfrom_fd; + +/** + * Run a client connected to an rsyncd. The alternative to this + * 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; - char *sargs[MAX_ARGS]; - int sargc=0; - char line[MAXPATHLEN]; + int fd, ret; char *p, *user=NULL; - extern int remote_version; - extern int am_sender; - extern struct in_addr socket_address; - + extern char *bind_address; + extern int default_af_hint; + + /* this is redundant with code in start_inband_exchange(), but + this short-circuits a problem before we open a socket, and + the extra check won't hurt */ if (*path == '/') { - rprintf(FERROR,"ERROR: The remote path must start with a module name\n"); + rprintf(FERROR,"ERROR: The remote path must start with a module name not a /\n"); return -1; } @@ -50,15 +71,53 @@ int start_socket_client(char *host, char *path, int argc, char *argv[]) *p = 0; } - 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); } - - server_options(sargs,&sargc); + + ret = start_inband_exchange(user, path, fd, fd, argc); + + return ret < 0? ret : client_run(fd, fd, -1, argc, argv); +} + +int start_inband_exchange(char *user, char *path, int f_in, int f_out, int argc) +{ + int i; + char *sargs[MAX_ARGS]; + int sargc = 0; + char line[MAXPATHLEN]; + char *p; + extern int remote_version; + extern int kludge_around_eof; + extern int am_sender; + extern int daemon_over_rsh; + extern int list_only; + + if (argc == 0 && !am_sender) + list_only = 1; + + if (*path == '/') { + rprintf(FERROR, "ERROR: The remote path must start with a module name\n"); + return -1; + } + + if (!user) user = getenv("USER"); + if (!user) user = getenv("LOGNAME"); + + /* set daemon_over_rsh to false since we need to build the + true set of args passed through the rsh/ssh connection; + this is a no-op for direct-socket-connection mode */ + daemon_over_rsh = 0; + server_options(sargs, &sargc); sargs[sargc++] = "."; @@ -67,113 +126,145 @@ int start_socket_client(char *host, char *path, int argc, char *argv[]) sargs[sargc] = NULL; - io_printf(fd,"@RSYNCD: %d\n", PROTOCOL_VERSION); + io_printf(f_out, "@RSYNCD: %d\n", PROTOCOL_VERSION); - if (!read_line(fd, line, sizeof(line)-1)) { + if (!read_line(f_in, 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; } p = strchr(path,'/'); if (p) *p = 0; - io_printf(fd,"%s\n",path); + io_printf(f_out, "%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)) { + if (!read_line(f_in, line, sizeof(line)-1)) { + rprintf(FERROR, "rsync: didn't get server startup line\n"); return -1; } if (strncmp(line,"@RSYNCD: AUTHREQD ",18) == 0) { - auth_client(fd, user, line+18); + auth_client(f_out, user, line+18); continue; } 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= 22 || (remote_version > 17 && !am_sender)) - io_start_multiplex_in(fd); + if (remote_version < 23) { + if (remote_version == 22 || (remote_version > 17 && !am_sender)) + io_start_multiplex_in(f_in); + } - return client_run(fd, fd, -1, argc, argv); + return 0; } -static int rsync_module(int fd, int i) +static int rsync_module(int f_in, int f_out, int i) { int argc=0; char *argv[MAX_ARGS]; char **argp; char line[MAXPATHLEN]; - uid_t uid = (uid_t)-2; + uid_t uid = (uid_t)-2; /* canonically "nobody" */ gid_t gid = (gid_t)-2; char *p; - char *addr = client_addr(fd); - char *host = client_name(fd); + char *addr = client_addr(f_in); + char *host = client_name(f_in); char *name = lp_name(i); int use_chroot = lp_use_chroot(i); int start_glob=0; int ret; char *request=NULL; extern int am_sender; + extern int am_server; + extern int am_daemon; extern int remote_version; extern int am_root; 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)); - io_printf(fd,"@ERROR: access denied to %s from %s (%s)\n", - name, client_name(fd), client_addr(fd)); + name, host, addr); + io_printf(f_out, "@ERROR: access denied to %s from %s (%s)\n", + name, host, addr); return -1; } + if (am_daemon && am_server) { + rprintf(FINFO, "rsync allowed access on module %s from %s (%s)\n", + name, host, addr); + } + if (!claim_connection(lp_lock_file(i), lp_max_connections(i))) { if (errno) { rprintf(FERROR,"failed to open lock file %s : %s\n", lp_lock_file(i), strerror(errno)); - io_printf(fd,"@ERROR: failed to open lock file %s : %s\n", + io_printf(f_out, "@ERROR: failed to open lock file %s : %s\n", lp_lock_file(i), strerror(errno)); } else { rprintf(FERROR,"max connections (%d) reached\n", lp_max_connections(i)); - io_printf(fd,"@ERROR: max connections (%d) reached - try again later\n", lp_max_connections(i)); + io_printf(f_out, "@ERROR: max connections (%d) reached - try again later\n", lp_max_connections(i)); } return -1; } - auth_user = auth_server(fd, i, addr, "@RSYNCD: AUTHREQD "); + auth_user = auth_server(f_in, f_out, i, addr, "@RSYNCD: AUTHREQD "); if (!auth_user) { rprintf(FERROR,"auth failed on module %s from %s (%s)\n", - name, client_name(fd), client_addr(fd)); - io_printf(fd,"@ERROR: auth failed on module %s\n",name); + name, host, addr); + io_printf(f_out, "@ERROR: auth failed on module %s\n", name); return -1; } module_id = i; - if (lp_read_only(i)) - read_only = 1; - am_root = (getuid() == 0); 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\n"); + io_printf(f_out, "@ERROR: invalid uid %s\n", p); return -1; } uid = atoi(p); @@ -181,14 +272,21 @@ 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\n"); + io_printf(f_out, "@ERROR: invalid gid %s\n", p); return -1; } gid = atoi(p); } } + + /* TODO: If we're not root, but the configuration requests + * that we change to some uid other than the current one, then + * log a warning. */ + + /* TODO: Perhaps take a list of gids, and make them into the + * supplementary groups. */ p = lp_include_from(i); add_exclude_file(p, 1, 1); @@ -202,52 +300,84 @@ static int rsync_module(int fd, int i) p = lp_exclude(i); add_exclude_line(p); - log_open(); + 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))) { - rprintf(FERROR,"chroot %s failed\n", lp_path(i)); - io_printf(fd,"@ERROR: chroot failed\n"); + rsyserr(FERROR, errno, "chroot %s failed", lp_path(i)); + io_printf(f_out, "@ERROR: chroot failed\n"); return -1; } if (!push_dir("/", 0)) { - rprintf(FERROR,"chdir %s failed\n", lp_path(i)); - io_printf(fd,"@ERROR: chdir failed\n"); + rsyserr(FERROR, errno, "chdir %s failed\n", lp_path(i)); + io_printf(f_out, "@ERROR: chdir failed\n"); return -1; } } else { if (!push_dir(lp_path(i), 0)) { - rprintf(FERROR,"chdir %s failed\n", lp_path(i)); - io_printf(fd,"@ERROR: chdir failed\n"); + rsyserr(FERROR, errno, "chdir %s failed\n", lp_path(i)); + io_printf(f_out, "@ERROR: chdir failed\n"); return -1; } sanitize_paths = 1; } 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(f_out, "@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)) { - rprintf(FERROR,"setgid %d failed\n", gid); - io_printf(fd,"@ERROR: setgid failed\n"); + rsyserr(FERROR, errno, "setgid %d failed", (int) gid); + io_printf(f_out, "@ERROR: setgid failed\n"); return -1; } if (setuid(uid)) { - rprintf(FERROR,"setuid %d failed\n", uid); - io_printf(fd,"@ERROR: setuid failed\n"); + rsyserr(FERROR, errno, "setuid %d failed", (int) uid); + io_printf(f_out, "@ERROR: setuid failed\n"); return -1; } am_root = (getuid() == 0); } - io_printf(fd,"@RSYNCD: OK\n"); + io_printf(f_out, "@RSYNCD: OK\n"); argv[argc++] = "rsyncd"; while (1) { - if (!read_line(fd, line, sizeof(line)-1)) { + if (!read_line(f_in, line, sizeof(line)-1)) { return -1; } @@ -292,7 +422,11 @@ static int rsync_module(int fd, int i) } } - ret = parse_arguments(argc, argv, 0); + argp = argv; + ret = parse_arguments(&argc, (const char ***) &argp, 0); + + if (filesfrom_fd == 0) + filesfrom_fd = f_in; if (request) { if (*auth_user) { @@ -307,28 +441,27 @@ static int rsync_module(int fd, int i) free(request); } -#if !TRIDGE +#ifndef DEBUG /* don't allow the logs to be flooded too fast */ if (verbose > 1) verbose = 1; #endif - argc -= optind; - argp = argv + optind; - optind = 0; - - if (remote_version >= 22 || (remote_version > 17 && am_sender)) - io_start_multiplex_out(fd); - - if (read_only) { - extern int am_sender; - if (!am_sender) { - rprintf(FERROR,"ERROR: module is read only\n"); - return -1; - } + if (remote_version < 23) { + if (remote_version == 22 || (remote_version > 17 && am_sender)) + io_start_multiplex_out(f_out); } - + + /* For later protocol versions, we don't start multiplexing + * until we've configured nonblocking in start_server. That + * means we're in a sticky situation now: there's no way to + * convey errors to the client. */ + + /* FIXME: Hold off on reporting option processing errors until + * we've set up nonblocking and multiplexed IO and can get the + * message back to them. */ if (!ret) { - option_error(); + option_error(); + exit_cleanup(RERR_UNSUPPORTED); } if (lp_timeout(i)) { @@ -336,7 +469,7 @@ static int rsync_module(int fd, int i) io_timeout = lp_timeout(i); } - start_server(fd, fd, argc, argp); + start_server(f_in, f_out, argc, argp); return 0; } @@ -347,32 +480,41 @@ static void send_listing(int fd) { int n = lp_numservices(); int i; - + extern int remote_version; + for (i=0;i= 25) + io_printf(fd,"@RSYNCD: EXIT\n"); } -/* this is called when a socket connection is established to a client +/* this is called when a connection is established to a client and we want to start talking. The setup of the system is done from here */ -static int start_daemon(int fd) +int start_daemon(int f_in, int f_out) { char line[200]; char *motd; int i = -1; extern char *config_file; extern int remote_version; + extern int am_server; if (!lp_load(config_file, 0)) { exit_cleanup(RERR_SYNTAX); } - set_socket_options(fd,"SO_KEEPALIVE"); - set_socket_options(fd,lp_socket_options()); - + log_init(); + + if (!am_server) { + set_socket_options(f_in, "SO_KEEPALIVE"); + set_socket_options(f_in, lp_socket_options()); + set_nonblocking(f_in); + } - io_printf(fd,"@RSYNCD: %d\n", PROTOCOL_VERSION); + io_printf(f_out, "@RSYNCD: %d\n", PROTOCOL_VERSION); motd = lp_motd_file(); if (motd && *motd) { @@ -381,47 +523,47 @@ static int start_daemon(int fd) int len = fread(line, 1, sizeof(line)-1, f); if (len > 0) { line[len] = 0; - io_printf(fd,"%s", line); + io_printf(f_out, "%s", line); } } if (f) fclose(f); - io_printf(fd,"\n"); + io_printf(f_out, "\n"); } - if (!read_line(fd, line, sizeof(line)-1)) { + if (!read_line(f_in, line, sizeof(line)-1)) { return -1; } if (sscanf(line,"@RSYNCD: %d", &remote_version) != 1) { - io_printf(fd,"@ERROR: protocol startup error\n"); + io_printf(f_out, "@ERROR: protocol startup error\n"); return -1; } while (i == -1) { line[0] = 0; - if (!read_line(fd, line, sizeof(line)-1)) { + if (!read_line(f_in, line, sizeof(line)-1)) { return -1; } if (!*line || strcmp(line,"#list")==0) { - send_listing(fd); + send_listing(f_out); return -1; } if (*line == '#') { /* it's some sort of command that I don't understand */ - io_printf(fd,"@ERROR: Unknown command '%s'\n", line); + io_printf(f_out, "@ERROR: Unknown command '%s'\n", line); return -1; } i = lp_number(line); if (i == -1) { - io_printf(fd,"@ERROR: Unknown module '%s'\n", line); + io_printf(f_out, "@ERROR: Unknown module '%s'\n", line); return -1; } } - return rsync_module(fd, i); + return rsync_module(f_in, f_out, i); } @@ -430,6 +572,7 @@ 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; @@ -442,19 +585,24 @@ int daemon_main(void) open("/dev/null", O_RDWR); } - return start_daemon(STDIN_FILENO); + return start_daemon(STDIN_FILENO, STDIN_FILENO); } - become_daemon(); + if (!no_detach) + become_daemon(); if (!lp_load(config_file, 1)) { - fprintf(stderr,"failed to load config file %s\n", config_file); exit_cleanup(RERR_SYNTAX); } - log_open(); + log_init(); - rprintf(FINFO,"rsyncd version %s starting\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. 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]; @@ -464,10 +612,10 @@ int daemon_main(void) if ((fd = do_open(lp_pid_file(), O_WRONLY|O_CREAT|O_TRUNC, 0666 & ~orig_umask)) == -1) { cleanup_set_pid(0); - fprintf(stderr,"failed to create pid file %s\n", pid_file); + 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); }