X-Git-Url: https://mattmccutchen.net/rsync/rsync.git/blobdiff_plain/a538066d5acd059903cff5103d944cad1fb5c7b2..d62bcc17f303f30d1e3df1051b1390202a21cf9c:/clientserver.c diff --git a/clientserver.c b/clientserver.c index 1b3801bc..a1e15c06 100644 --- a/clientserver.c +++ b/clientserver.c @@ -1,68 +1,80 @@ /* -*- c-file-style: "linux"; -*- - - Copyright (C) 1998-2001 by Andrew Tridgell - Copyright (C) 2001 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. -*/ - -/* the socket based protocol for setting up a connection with rsyncd */ + * + * 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" +extern int am_sender; +extern int am_server; +extern int am_daemon; +extern int am_root; extern int module_id; extern int read_only; extern int verbose; extern int rsync_port; +extern int kludge_around_eof; +extern int daemon_over_rsh; +extern int list_only; +extern int sanitize_paths; +extern int filesfrom_fd; +extern int remote_protocol; +extern int protocol_version; +extern int io_timeout; +extern int orig_umask; +extern int no_detach; +extern int default_af_hint; +extern char *bind_address; +extern struct exclude_list_struct server_exclude_list; +extern char *exclude_path_prefix; +extern char *config_file; + char *auth_user; -int sanitize_paths = 0; -/* +/** * 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; - 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 char *shell_cmd; - extern int kludge_around_eof; - extern char *bind_address; - - if (argc == 0 && !am_sender) { - extern int list_only; - list_only = 1; - } - /* This is just a friendliness enhancement: if the connection - * is to an rsyncd then there is no point specifying the -e option. - * Note that this is only set if the -e was explicitly specified, - * not if the environment variable just happens to be set. - * See http://lists.samba.org/pipermail/rsync/2000-September/002744.html - */ - if (shell_cmd) { - rprintf(FERROR, "WARNING: --rsh or -e option ignored when " - "connecting to rsync daemon\n"); - /* continue */ - } - + /* 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 not a /\n"); return -1; @@ -75,77 +87,121 @@ int start_socket_client(char *host, char *path, int argc, char *argv[]) *p = 0; } + fd = open_socket_out_wrapped(host, rsync_port, bind_address, + default_af_hint); + if (fd == -1) + exit_cleanup(RERR_SOCKETIO); + + 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; + + 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"); - fd = open_socket_out_wrapped (host, rsync_port, bind_address, - global_opts.af_hint); - if (fd == -1) { - exit_cleanup(RERR_SOCKETIO); - } - - server_options(sargs,&sargc); + /* 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++] = "."; - if (path && *path) + if (path && *path) sargs[sargc++] = path; 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) { + if (sscanf(line,"@RSYNCD: %d", &remote_protocol) != 1) { + /* note that read_line strips of \n or \r */ + rprintf(FERROR, "rsync: server sent \"%s\" rather than greeting\n", + line); return -1; } + if (protocol_version > remote_protocol) + protocol_version = remote_protocol; 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 = remote_version < 25; + kludge_around_eof = list_only && (protocol_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; - if (strcmp(line,"@RSYNCD: EXIT") == 0) exit(0); + 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); + } - rprintf(FINFO,"%s\n", line); + 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 17 && !am_sender)) - io_start_multiplex_in(fd); + if (protocol_version < 23) { + if (protocol_version == 22 || !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]; @@ -154,93 +210,105 @@ static int rsync_module(int fd, int i) 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 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", - lp_lock_file(i), strerror(errno)); + rsyserr(FERROR, errno, "failed to open lock file %s", + lp_lock_file(i)); + io_printf(f_out, "@ERROR: failed to open lock file %s\n", + lp_lock_file(i)); } 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); - return -1; + name, host, addr); + io_printf(f_out, "@ERROR: auth failed on module %s\n", name); + return -1; } module_id = i; - am_root = (getuid() == 0); + am_root = (MY_UID() == 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 %s\n", p); + io_printf(f_out, "@ERROR: invalid uid %s\n", p); return -1; - } + } uid = atoi(p); } 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); + 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. */ + /* 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. */ + + exclude_path_prefix = use_chroot? "" : lp_path(i); + if (*exclude_path_prefix == '/' && !exclude_path_prefix[1]) + exclude_path_prefix = ""; p = lp_include_from(i); - add_exclude_file(p, 1, 1); + add_exclude_file(&server_exclude_list, p, + XFLG_FATAL_ERRORS | XFLG_DEF_INCLUDE); p = lp_include(i); - add_include_line(p); + add_exclude(&server_exclude_list, p, + XFLG_WORD_SPLIT | XFLG_DEF_INCLUDE); p = lp_exclude_from(i); - add_exclude_file(p, 1, 0); + add_exclude_file(&server_exclude_list, p, + XFLG_FATAL_ERRORS); p = lp_exclude(i); - add_exclude_line(p); + add_exclude(&server_exclude_list, p, XFLG_WORD_SPLIT); + + exclude_path_prefix = NULL; log_init(); @@ -259,47 +327,66 @@ static int rsync_module(int fd, int i) */ if (chroot(lp_path(i))) { rsyserr(FERROR, errno, "chroot %s failed", lp_path(i)); - io_printf(fd,"@ERROR: chroot failed\n"); + io_printf(f_out, "@ERROR: chroot failed\n"); return -1; } - if (!push_dir("/", 0)) { - rsyserr(FERROR, errno, "chdir %s failed\n", lp_path(i)); - io_printf(fd,"@ERROR: chdir failed\n"); + if (!push_dir("/")) { + 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)) { + if (!push_dir(lp_path(i))) { rsyserr(FERROR, errno, "chdir %s failed\n", lp_path(i)); - io_printf(fd,"@ERROR: chdir failed\n"); + io_printf(f_out, "@ERROR: chdir failed\n"); return -1; } sanitize_paths = 1; } if (am_root) { + /* 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", (int) gid); - io_printf(fd,"@ERROR: setgid failed\n"); + io_printf(f_out, "@ERROR: setgid failed\n"); + return -1; + } +#ifdef HAVE_SETGROUPS + /* Get rid of any supplementary groups this process + * might have inheristed. */ + if (setgroups(1, &gid)) { + rsyserr(FERROR, errno, "setgroups failed"); + io_printf(f_out, "@ERROR: setgroups failed\n"); return -1; } +#endif if (setuid(uid)) { rsyserr(FERROR, errno, "setuid %d failed", (int) uid); - io_printf(fd,"@ERROR: setuid failed\n"); + io_printf(f_out, "@ERROR: setuid failed\n"); return -1; } - am_root = (getuid() == 0); + am_root = (MY_UID() == 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; } @@ -331,22 +418,12 @@ static int rsync_module(int fd, int i) } } - if (sanitize_paths) { - /* - * Note that this is applied to all parameters, whether or not - * they are filenames, but no other legal parameters contain - * the forms that need to be sanitized so it doesn't hurt; - * it is not known at this point which parameters are files - * and which aren't. - */ - for (i = 1; i < argc; i++) { - sanitize_path(argv[i], NULL); - } - } - - argp = argv; + argp = argv; ret = parse_arguments(&argc, (const char ***) &argp, 0); + if (filesfrom_fd == 0) + filesfrom_fd = f_in; + if (request) { if (*auth_user) { rprintf(FINFO,"rsync %s %s from %s@%s (%s)\n", @@ -362,33 +439,33 @@ static int rsync_module(int fd, int i) #ifndef DEBUG /* don't allow the logs to be flooded too fast */ - if (verbose > 1) verbose = 1; + if (verbose > lp_max_verbosity()) + verbose = lp_max_verbosity(); #endif - if (remote_version < 23) { - if (remote_version == 22 || (remote_version > 17 && am_sender)) - io_start_multiplex_out(fd); + if (protocol_version < 23) { + if (protocol_version == 22 || 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. */ + + /* 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(); - exit_cleanup(RERR_UNSUPPORTED); + option_error(); + exit_cleanup(RERR_UNSUPPORTED); } if (lp_timeout(i)) { - extern int io_timeout; io_timeout = lp_timeout(i); } - start_server(fd, fd, argc, argp); + start_server(f_in, f_out, argc, argp); return 0; } @@ -399,36 +476,37 @@ static void send_listing(int fd) { int n = lp_numservices(); int i; - extern int remote_version; for (i=0;i= 25) + if (protocol_version >= 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; if (!lp_load(config_file, 0)) { exit_cleanup(RERR_SYNTAX); } - set_socket_options(fd,"SO_KEEPALIVE"); - set_socket_options(fd,lp_socket_options()); - set_nonblocking(fd); + 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) { @@ -437,72 +515,72 @@ 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"); + if (sscanf(line,"@RSYNCD: %d", &remote_protocol) != 1) { + io_printf(f_out, "@ERROR: protocol startup error\n"); return -1; - } + } + if (protocol_version > remote_protocol) + protocol_version = remote_protocol; 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); } int daemon_main(void) { - extern char *config_file; - extern int orig_umask; char *pid_file; if (is_a_socket(STDIN_FILENO)) { int i; /* we are running via inetd - close off stdout and - stderr so that library functions (and getopt) don't - try to use them. Redirect them to /dev/null */ + * stderr so that library functions (and getopt) don't + * try to use them. Redirect them to /dev/null */ for (i=1;i<3;i++) { - close(i); + close(i); open("/dev/null", O_RDWR); } - return start_daemon(STDIN_FILENO); + return start_daemon(STDIN_FILENO, STDIN_FILENO); } - if (!global_opts.no_detach) - become_daemon(); + if (!no_detach) + become_daemon(); if (!lp_load(config_file, 1)) { exit_cleanup(RERR_SYNTAX); @@ -511,24 +589,23 @@ int daemon_main(void) log_init(); 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??? */ + 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]; int fd; - int pid = (int) getpid(); + pid_t pid = getpid(); cleanup_set_pid(pid); if ((fd = do_open(lp_pid_file(), O_WRONLY|O_CREAT|O_TRUNC, 0666 & ~orig_umask)) == -1) { - cleanup_set_pid(0); - rsyserr(FLOG, errno, "failed to create pid file %s", pid_file); - exit_cleanup(RERR_FILEIO); + cleanup_set_pid(0); + rsyserr(FLOG, errno, "failed to create pid file %s", pid_file); + exit_cleanup(RERR_FILEIO); } - snprintf(pidbuf, sizeof(pidbuf), "%d\n", pid); + snprintf(pidbuf, sizeof pidbuf, "%ld\n", (long)pid); write(fd, pidbuf, strlen(pidbuf)); close(fd); } @@ -536,4 +613,3 @@ int daemon_main(void) start_accept_loop(rsync_port, start_daemon); return -1; } -