X-Git-Url: https://mattmccutchen.net/rsync/rsync.git/blobdiff_plain/31ec50d7da5836163fa8d8ea15038ca3f88caf3e..c120ff37f549e50732948ee236d5680b1e7158e9:/clientserver.c diff --git a/clientserver.c b/clientserver.c index 4c44d26e..8a26ed5a 100644 --- a/clientserver.c +++ b/clientserver.c @@ -1,24 +1,29 @@ /* -*- 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" @@ -27,43 +32,33 @@ 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. - */ + * 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; extern int default_af_hint; - 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; @@ -76,16 +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"); - + 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++] = "."; @@ -94,59 +126,77 @@ 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 = remote_version < 25; + 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; - 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); + 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]; @@ -155,46 +205,53 @@ 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 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, host, addr); - io_printf(fd,"@ERROR: access denied to %s from %s (%s)\n", + 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; } @@ -205,9 +262,9 @@ 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); + io_printf(f_out, "@ERROR: invalid uid %s\n", p); return -1; } uid = atoi(p); @@ -215,9 +272,9 @@ 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); + io_printf(f_out, "@ERROR: invalid gid %s\n", p); return -1; } gid = atoi(p); @@ -260,47 +317,67 @@ 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"); + io_printf(f_out, "@ERROR: chdir failed\n"); return -1; } } else { if (!push_dir(lp_path(i), 0)) { 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) { +#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)) { 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; } 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); } - 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; } @@ -348,6 +425,9 @@ static int rsync_module(int fd, int i) 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", @@ -368,7 +448,7 @@ static int rsync_module(int fd, int i) if (remote_version < 23) { if (remote_version == 22 || (remote_version > 17 && am_sender)) - io_start_multiplex_out(fd); + io_start_multiplex_out(f_out); } /* For later protocol versions, we don't start multiplexing @@ -389,7 +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; } @@ -410,26 +490,31 @@ static void send_listing(int fd) 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()); - 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) { @@ -438,47 +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); } @@ -500,7 +585,7 @@ int daemon_main(void) open("/dev/null", O_RDWR); } - return start_daemon(STDIN_FILENO); + return start_daemon(STDIN_FILENO, STDIN_FILENO); } if (!no_detach)