diff options
Diffstat (limited to 'clientserver.c')
| -rw-r--r-- | clientserver.c | 1538 |
1 files changed, 1538 insertions, 0 deletions
diff --git a/clientserver.c b/clientserver.c new file mode 100644 index 0000000..7c897ab --- /dev/null +++ b/clientserver.c @@ -0,0 +1,1538 @@ +/* + * The socket based protocol for setting up a connection with rsyncd. + * + * Copyright (C) 1998-2001 Andrew Tridgell <tridge@samba.org> + * Copyright (C) 2001-2002 Martin Pool <mbp@samba.org> + * Copyright (C) 2002-2022 Wayne Davison + * + * 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 3 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, visit the http://fsf.org website. + */ + +#include "rsync.h" +#include "itypes.h" +#include "ifuncs.h" + +extern int quiet; +extern int dry_run; +extern int output_motd; +extern int list_only; +extern int am_sender; +extern int am_server; +extern int am_daemon; +extern int am_root; +extern int msgs2stderr; +extern int rsync_port; +extern int protect_args; +extern int ignore_errors; +extern int preserve_xattrs; +extern int kluge_around_eof; +extern int munge_symlinks; +extern int open_noatime; +extern int sanitize_paths; +extern int numeric_ids; +extern int filesfrom_fd; +extern int remote_protocol; +extern int protocol_version; +extern int io_timeout; +extern int no_detach; +extern int write_batch; +extern int old_style_args; +extern int default_af_hint; +extern int logfile_format_has_i; +extern int logfile_format_has_o_or_i; +extern char *bind_address; +extern char *config_file; +extern char *logfile_format; +extern char *files_from; +extern char *tmpdir; +extern char *early_input_file; +extern struct chmod_mode_struct *chmod_modes; +extern filter_rule_list daemon_filter_list; +#ifdef ICONV_OPTION +extern char *iconv_opt; +extern iconv_t ic_send, ic_recv; +#endif +extern uid_t our_uid; +extern gid_t our_gid; + +char *auth_user; +char *daemon_auth_choices; +int read_only = 0; +int module_id = -1; +int pid_file_fd = -1; +int early_input_len = 0; +char *early_input = NULL; +pid_t namecvt_pid = 0; +struct chmod_mode_struct *daemon_chmod_modes; + +#define EARLY_INPUT_CMD "#early_input=" +#define EARLY_INPUT_CMDLEN (sizeof EARLY_INPUT_CMD - 1) + +/* module_dirlen is the length of the module_dir string when in daemon + * mode and module_dir is not "/"; otherwise 0. (Note that a chroot- + * enabled module can have a non-"/" module_dir these days.) */ +char *module_dir = NULL; +unsigned int module_dirlen = 0; + +char *full_module_path; + +static int rl_nulls = 0; +static int namecvt_fd_req = -1, namecvt_fd_ans = -1; + +#ifdef HAVE_SIGACTION +static struct sigaction sigact; +#endif + +static item_list gid_list = EMPTY_ITEM_LIST; + +/* Used when "reverse lookup" is off. */ +const char undetermined_hostname[] = "UNDETERMINED"; + +/** + * 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, int remote_argc, char *remote_argv[], + int argc, char *argv[]) +{ + int fd, ret; + char *p, *user = NULL; + + /* This is redundant with code in start_inband_exchange(), but this + * short-circuits a problem in the client before we open a socket, + * and the extra check won't hurt. */ + if (**remote_argv == '/') { + rprintf(FERROR, + "ERROR: The remote path must start with a module name not a /\n"); + return -1; + } + + if ((p = strrchr(host, '@')) != NULL) { + user = host; + host = p+1; + *p = '\0'; + } + + fd = open_socket_out_wrapped(host, rsync_port, bind_address, default_af_hint); + if (fd == -1) + exit_cleanup(RERR_SOCKETIO); + +#ifdef ICONV_CONST + setup_iconv(); +#endif + + ret = start_inband_exchange(fd, fd, user, remote_argc, remote_argv); + + return ret ? ret : client_run(fd, fd, -1, argc, argv); +} + +static int exchange_protocols(int f_in, int f_out, char *buf, size_t bufsiz, int am_client) +{ + int remote_sub = -1; + int our_sub = get_subprotocol_version(); + + output_daemon_greeting(f_out, am_client); + if (!am_client) { + char *motd = lp_motd_file(); + if (motd && *motd) { + FILE *f = fopen(motd, "r"); + while (f && !feof(f)) { + int len = fread(buf, 1, bufsiz - 1, f); + if (len > 0) + write_buf(f_out, buf, len); + } + if (f) + fclose(f); + write_sbuf(f_out, "\n"); + } + } + + /* This strips the \n. */ + if (!read_line_old(f_in, buf, bufsiz, 0)) { + if (am_client) + rprintf(FERROR, "rsync: did not see server greeting\n"); + return -1; + } + + if (sscanf(buf, "@RSYNCD: %d.%d", &remote_protocol, &remote_sub) < 1) { + if (am_client) + rprintf(FERROR, "rsync: server sent \"%s\" rather than greeting\n", buf); + else + io_printf(f_out, "@ERROR: protocol startup error\n"); + return -1; + } + + if (remote_sub < 0) { + if (remote_protocol >= 30) { + if (am_client) + rprintf(FERROR, "rsync: the server omitted the subprotocol value: %s\n", buf); + else + io_printf(f_out, "@ERROR: your client omitted the subprotocol value: %s\n", buf); + return -1; + } + remote_sub = 0; + } + + daemon_auth_choices = strchr(buf + 9, ' '); + if (daemon_auth_choices) { + char *cp; + daemon_auth_choices = strdup(daemon_auth_choices + 1); + if ((cp = strchr(daemon_auth_choices, '\n')) != NULL) + *cp = '\0'; + } else if (remote_protocol > 31) { + if (am_client) + rprintf(FERROR, "rsync: the server omitted the digest name list: %s\n", buf); + else + io_printf(f_out, "@ERROR: your client omitted the digest name list: %s\n", buf); + return -1; + } + + if (protocol_version > remote_protocol) { + protocol_version = remote_protocol; + if (remote_sub) + protocol_version--; + } else if (protocol_version == remote_protocol) { + if (remote_sub != our_sub) + protocol_version--; + } +#if SUBPROTOCOL_VERSION != 0 + else if (protocol_version < remote_protocol) { + if (our_sub) + protocol_version--; + } +#endif + + if (protocol_version >= 30) + rl_nulls = 1; + + return 0; +} + +int start_inband_exchange(int f_in, int f_out, const char *user, int argc, char *argv[]) +{ + int i, modlen; + char line[BIGPATHBUFLEN]; + char *sargs[MAX_ARGS]; + int sargc = 0; + char *p, *modname; + + assert(argc > 0 && *argv != NULL); + + if (**argv == '/') { + rprintf(FERROR, + "ERROR: The remote path must start with a module name\n"); + return -1; + } + + if (!(p = strchr(*argv, '/'))) + modlen = strlen(*argv); + else + modlen = p - *argv; + + modname = new_array(char, modlen+1+1); /* room for '/' & '\0' */ + strlcpy(modname, *argv, modlen + 1); + modname[modlen] = '/'; + modname[modlen+1] = '\0'; + + if (!user) + user = getenv("USER"); + if (!user) + user = getenv("LOGNAME"); + + if (exchange_protocols(f_in, f_out, line, sizeof line, 1) < 0) + return -1; + + if (early_input_file) { + STRUCT_STAT st; + FILE *f = fopen(early_input_file, "rb"); + if (!f || do_fstat(fileno(f), &st) < 0) { + rsyserr(FERROR, errno, "failed to open %s", early_input_file); + return -1; + } + early_input_len = st.st_size; + if (early_input_len > (int)sizeof line) { + rprintf(FERROR, "%s is > %d bytes.\n", early_input_file, (int)sizeof line); + return -1; + } + if (early_input_len > 0) { + io_printf(f_out, EARLY_INPUT_CMD "%d\n", early_input_len); + while (early_input_len > 0) { + int len; + if (feof(f)) { + rprintf(FERROR, "Early EOF in %s\n", early_input_file); + return -1; + } + len = fread(line, 1, early_input_len, f); + if (len > 0) { + write_buf(f_out, line, len); + early_input_len -= len; + } + } + } + fclose(f); + } + + server_options(sargs, &sargc); + + if (sargc >= MAX_ARGS - 2) + goto arg_overflow; + + sargs[sargc++] = "."; + + if (!old_style_args) + snprintf(line, sizeof line, " %.*s/", modlen, modname); + + while (argc > 0) { + if (sargc >= MAX_ARGS - 1) { + arg_overflow: + rprintf(FERROR, "internal: args[] overflowed in do_cmd()\n"); + exit_cleanup(RERR_SYNTAX); + } + if (strncmp(*argv, modname, modlen) == 0 && argv[0][modlen] == '\0') + sargs[sargc++] = modname; /* we send "modname/" */ + else { + char *arg = *argv; + int extra_chars = *arg == '-' ? 2 : 0; /* a leading dash needs a "./" prefix. */ + /* If --old-args was not specified, make sure that the arg won't split at a mod name! */ + if (!old_style_args && (p = strstr(arg, line)) != NULL) { + do { + extra_chars += 2; + } while ((p = strstr(p+1, line)) != NULL); + } + if (extra_chars) { + char *f = arg; + char *t = arg = new_array(char, strlen(arg) + extra_chars + 1); + if (*f == '-') { + *t++ = '.'; + *t++ = '/'; + } + while (*f) { + if (*f == ' ' && strncmp(f, line, modlen+2) == 0) { + *t++ = '['; + *t++ = *f++; + *t++ = ']'; + } else + *t++ = *f++; + } + *t = '\0'; + } + sargs[sargc++] = arg; + } + argv++; + argc--; + } + + sargs[sargc] = NULL; + + if (DEBUG_GTE(CMD, 1)) + print_child_argv("sending daemon args:", sargs); + + io_printf(f_out, "%.*s\n", modlen, modname); + + /* Old servers may just drop the connection here, + rather than sending a proper EXIT command. Yuck. */ + kluge_around_eof = list_only && protocol_version < 25 ? 1 : 0; + + while (1) { + if (!read_line_old(f_in, line, sizeof line, 0)) { + rprintf(FERROR, "rsync: didn't get server startup line\n"); + return -1; + } + + if (strncmp(line,"@RSYNCD: AUTHREQD ",18) == 0) { + auth_client(f_out, user, line+18); + continue; + } + + if (strcmp(line,"@RSYNCD: OK") == 0) + break; + + 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 -1; + } + + /* This might be a MOTD line or a module listing, but there is + * no way to differentiate it. The manpage mentions this. */ + if (output_motd) + rprintf(FINFO, "%s\n", line); + } + kluge_around_eof = 0; + + if (rl_nulls) { + for (i = 0; i < sargc; i++) { + if (!sargs[i]) /* stop at --secluded-args NULL */ + break; + write_sbuf(f_out, sargs[i]); + write_byte(f_out, 0); + } + write_byte(f_out, 0); + } else { + for (i = 0; i < sargc; i++) + io_printf(f_out, "%s\n", sargs[i]); + write_sbuf(f_out, "\n"); + } + + if (protect_args) + send_protected_args(f_out, sargs); + + if (protocol_version < 23) { + if (protocol_version == 22 || !am_sender) + io_start_multiplex_in(f_in); + } + + free(modname); + + return 0; +} + +#if defined HAVE_SETENV || defined HAVE_PUTENV +static int read_arg_from_pipe(int fd, char *buf, int limit) +{ + char *bp = buf, *eob = buf + limit - 1; + + while (1) { + int got = read(fd, bp, 1); + if (got != 1) { + if (got < 0 && errno == EINTR) + continue; + return -1; + } + if (*bp == '\0') + break; + if (bp < eob) + bp++; + } + *bp = '\0'; + + return bp - buf; +} +#endif + +void set_env_str(const char *var, const char *str) +{ +#ifdef HAVE_SETENV + if (setenv(var, str, 1) < 0) + out_of_memory("set_env_str"); +#else +#ifdef HAVE_PUTENV + char *mem; + if (asprintf(&mem, "%s=%s", var, str) < 0) + out_of_memory("set_env_str"); + putenv(mem); +#else + (void)var; + (void)str; +#endif +#endif +} + +#if defined HAVE_SETENV || defined HAVE_PUTENV + +static void set_envN_str(const char *var, int num, const char *str) +{ +#ifdef HAVE_SETENV + char buf[128]; + (void)snprintf(buf, sizeof buf, "%s%d", var, num); + if (setenv(buf, str, 1) < 0) + out_of_memory("set_env_str"); +#else +#ifdef HAVE_PUTENV + char *mem; + if (asprintf(&mem, "%s%d=%s", var, num, str) < 0) + out_of_memory("set_envN_str"); + putenv(mem); +#endif +#endif +} + +void set_env_num(const char *var, long num) +{ +#ifdef HAVE_SETENV + char val[64]; + (void)snprintf(val, sizeof val, "%ld", num); + if (setenv(var, val, 1) < 0) + out_of_memory("set_env_str"); +#else +#ifdef HAVE_PUTENV + char *mem; + if (asprintf(&mem, "%s=%ld", var, num) < 0) + out_of_memory("set_env_num"); + putenv(mem); +#endif +#endif +} + +/* Used for "early exec", "pre-xfer exec", and the "name converter" script. */ +static pid_t start_pre_exec(const char *cmd, int *arg_fd_ptr, int *error_fd_ptr) +{ + int arg_fds[2], error_fds[2], arg_fd; + pid_t pid; + + if ((error_fd_ptr && pipe(error_fds) < 0) || pipe(arg_fds) < 0 || (pid = fork()) < 0) + return (pid_t)-1; + + if (pid == 0) { + char buf[BIGPATHBUFLEN]; + int j, len, status; + + if (error_fd_ptr) { + close(error_fds[0]); + set_blocking(error_fds[1]); + } + + close(arg_fds[1]); + arg_fd = arg_fds[0]; + set_blocking(arg_fd); + + len = read_arg_from_pipe(arg_fd, buf, BIGPATHBUFLEN); + if (len <= 0) + _exit(1); + set_env_str("RSYNC_REQUEST", buf); + + for (j = 0; ; j++) { + len = read_arg_from_pipe(arg_fd, buf, BIGPATHBUFLEN); + if (len <= 0) { + if (!len) + break; + _exit(1); + } + set_envN_str("RSYNC_ARG", j, buf); + } + + dup2(arg_fd, STDIN_FILENO); + close(arg_fd); + + if (error_fd_ptr) { + dup2(error_fds[1], STDOUT_FILENO); + close(error_fds[1]); + } + + status = shell_exec(cmd); + + if (!WIFEXITED(status)) + _exit(1); + _exit(WEXITSTATUS(status)); + } + + if (error_fd_ptr) { + close(error_fds[1]); + *error_fd_ptr = error_fds[0]; + set_blocking(error_fds[0]); + } + + close(arg_fds[0]); + arg_fd = *arg_fd_ptr = arg_fds[1]; + set_blocking(arg_fd); + + return pid; +} + +#endif + +static void write_pre_exec_args(int write_fd, char *request, char **early_argv, char **argv, int exec_type) +{ + int j = 0; + + if (!request) + request = "(NONE)"; + + write_buf(write_fd, request, strlen(request)+1); + if (early_argv) { + for ( ; *early_argv; early_argv++) + write_buf(write_fd, *early_argv, strlen(*early_argv)+1); + j = 1; /* Skip arg0 name in argv. */ + } + if (argv) { + for ( ; argv[j]; j++) + write_buf(write_fd, argv[j], strlen(argv[j])+1); + } + write_byte(write_fd, 0); + + if (exec_type == 1 && early_input_len) + write_buf(write_fd, early_input, early_input_len); + + if (exec_type != 2) /* the name converter needs this left open */ + close(write_fd); +} + +static char *finish_pre_exec(const char *desc, pid_t pid, int read_fd) +{ + char buf[BIGPATHBUFLEN], *bp, *cr; + int j, status = -1, msglen = sizeof buf - 1; + + if (read_fd >= 0) { + /* Read the stdout from the program. This it is only displayed + * to the user if the script also returns an error status. */ + for (bp = buf, cr = buf; msglen > 0; msglen -= j) { + if ((j = read(read_fd, bp, msglen)) <= 0) { + if (j == 0) + break; + if (errno == EINTR) + continue; + break; /* Just ignore the read error for now... */ + } + bp[j] = '\0'; + while (1) { + if ((cr = strchr(cr, '\r')) == NULL) { + cr = bp + j; + break; + } + if (!cr[1]) + break; /* wait for more data before we decide what to do */ + if (cr[1] == '\n') { + memmove(cr, cr+1, j - (cr - bp)); + j--; + } else + cr++; + } + bp += j; + } + *bp = '\0'; + + close(read_fd); + } else + *buf = '\0'; + + if (wait_process(pid, &status, 0) < 0 + || !WIFEXITED(status) || WEXITSTATUS(status) != 0) { + char *e; + if (asprintf(&e, "%s returned failure (%d)%s%s%s\n%s", + desc, status, status < 0 ? ": " : "", + status < 0 ? strerror(errno) : "", + *buf ? ":" : "", buf) < 0) + return "out_of_memory in finish_pre_exec\n"; + return e; + } + return NULL; +} + +static int path_failure(int f_out, const char *dir, BOOL was_chdir) +{ + if (was_chdir) + rsyserr(FLOG, errno, "chdir %s failed", dir); + else + rprintf(FLOG, "normalize_path(%s) failed\n", dir); + io_printf(f_out, "@ERROR: chdir failed\n"); + return -1; +} + +static int add_a_group(int f_out, const char *gname) +{ + gid_t gid, *gid_p; + if (!group_to_gid(gname, &gid, True)) { + rprintf(FLOG, "Invalid gid %s\n", gname); + io_printf(f_out, "@ERROR: invalid gid %s\n", gname); + return -1; + } + gid_p = EXPAND_ITEM_LIST(&gid_list, gid_t, -32); + *gid_p = gid; + return 0; +} + +#ifdef HAVE_GETGROUPLIST +static int want_all_groups(int f_out, uid_t uid) +{ + const char *err; + if ((err = getallgroups(uid, &gid_list)) != NULL) { + rsyserr(FLOG, errno, "%s", err); + io_printf(f_out, "@ERROR: %s\n", err); + return -1; + } + return 0; +} +#elif defined HAVE_INITGROUPS +static struct passwd *want_all_groups(int f_out, uid_t uid) +{ + struct passwd *pw; + gid_t *gid_p; + if ((pw = getpwuid(uid)) == NULL) { + rsyserr(FLOG, errno, "getpwuid failed"); + io_printf(f_out, "@ERROR: getpwuid failed\n"); + return NULL; + } + /* Start with the default group and initgroups() will add the rest. */ + gid_p = EXPAND_ITEM_LIST(&gid_list, gid_t, -32); + *gid_p = pw->pw_gid; + return pw; +} +#endif + +static int rsync_module(int f_in, int f_out, int i, const char *addr, const char *host) +{ + int argc; + char **argv, **orig_argv, **orig_early_argv, *module_chdir; + char line[BIGPATHBUFLEN]; +#if defined HAVE_INITGROUPS && !defined HAVE_GETGROUPLIST + struct passwd *pw = NULL; +#endif + uid_t uid; + int set_uid; + char *p, *err_msg = NULL; + char *name = lp_name(i); + int use_chroot = lp_use_chroot(i); /* might be 1 (yes), 0 (no), or -1 (unset) */ + int ret, pre_exec_arg_fd = -1, pre_exec_error_fd = -1; + int save_munge_symlinks; + pid_t pre_exec_pid = 0; + char *request = NULL; + + set_env_str("RSYNC_MODULE_NAME", name); + +#ifdef ICONV_OPTION + iconv_opt = lp_charset(i); + if (*iconv_opt) + setup_iconv(); + iconv_opt = NULL; +#endif + + /* If reverse lookup is disabled globally but enabled for this module, + * we need to do it now before the access check. */ + if (host == undetermined_hostname && lp_reverse_lookup(i)) + host = client_name(client_addr(f_in)); + set_env_str("RSYNC_HOST_NAME", host); + set_env_str("RSYNC_HOST_ADDR", addr); + + if (!allow_access(addr, &host, i)) { + rprintf(FLOG, "rsync denied on module %s from %s (%s)\n", + name, host, addr); + if (!lp_list(i)) + io_printf(f_out, "@ERROR: Unknown module '%s'\n", name); + else { + io_printf(f_out, + "@ERROR: access denied to %s from %s (%s)\n", + name, host, addr); + } + return -1; + } + + if (am_daemon > 0) { + rprintf(FLOG, "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) { + rsyserr(FLOG, errno, "failed to open lock file %s", + lp_lock_file(i)); + io_printf(f_out, "@ERROR: failed to open lock file\n"); + } else { + rprintf(FLOG, "max connections (%d) reached\n", + lp_max_connections(i)); + io_printf(f_out, "@ERROR: max connections (%d) reached -- try again later\n", + lp_max_connections(i)); + } + return -1; + } + + read_only = lp_read_only(i); /* may also be overridden by auth_server() */ + auth_user = auth_server(f_in, f_out, i, host, addr, "@RSYNCD: AUTHREQD "); + + if (!auth_user) { + io_printf(f_out, "@ERROR: auth failed on module %s\n", name); + return -1; + } + set_env_str("RSYNC_USER_NAME", auth_user); + + module_id = i; + + if (lp_transfer_logging(module_id) && !logfile_format) + logfile_format = lp_log_format(module_id); + if (log_format_has(logfile_format, 'i')) + logfile_format_has_i = 1; + if (logfile_format_has_i || log_format_has(logfile_format, 'o')) + logfile_format_has_o_or_i = 1; + + uid = MY_UID(); + am_root = (uid == ROOT_UID); + + p = *lp_uid(module_id) ? lp_uid(module_id) : am_root ? NOBODY_USER : NULL; + if (p) { + if (!user_to_uid(p, &uid, True)) { + rprintf(FLOG, "Invalid uid %s\n", p); + io_printf(f_out, "@ERROR: invalid uid %s\n", p); + return -1; + } + set_uid = 1; + } else + set_uid = 0; + + p = *lp_gid(module_id) ? conf_strtok(lp_gid(module_id)) : NULL; + if (p) { + /* The "*" gid must be the first item in the list. */ + if (strcmp(p, "*") == 0) { +#ifdef HAVE_GETGROUPLIST + if (want_all_groups(f_out, uid) < 0) + return -1; +#elif defined HAVE_INITGROUPS + if ((pw = want_all_groups(f_out, uid)) == NULL) + return -1; +#else + rprintf(FLOG, "This rsync does not support a gid of \"*\"\n"); + io_printf(f_out, "@ERROR: invalid gid setting.\n"); + return -1; +#endif + } else if (add_a_group(f_out, p) < 0) + return -1; + while ((p = conf_strtok(NULL)) != NULL) { +#if defined HAVE_INITGROUPS && !defined HAVE_GETGROUPLIST + if (pw) { + rprintf(FLOG, "This rsync cannot add groups after \"*\".\n"); + io_printf(f_out, "@ERROR: invalid gid setting.\n"); + return -1; + } +#endif + if (add_a_group(f_out, p) < 0) + return -1; + } + } else if (am_root) { + if (add_a_group(f_out, NOBODY_GROUP) < 0) + return -1; + } + + module_dir = lp_path(module_id); + if (*module_dir == '\0') { + rprintf(FLOG, "No path specified for module %s\n", name); + io_printf(f_out, "@ERROR: no path setting.\n"); + return -1; + } + if (use_chroot < 0) { + if (strstr(module_dir, "/./") != NULL) + use_chroot = 1; /* The module is expecting a chroot inner & outer path. */ + else if (chroot("/") < 0) { + rprintf(FLOG, "chroot test failed: %s. " + "Switching 'use chroot' from unset to false.\n", + strerror(errno)); + use_chroot = 0; + } else { + if (chdir("/") < 0) + rsyserr(FLOG, errno, "chdir(\"/\") failed"); + use_chroot = 1; + } + } + if (use_chroot) { + if ((p = strstr(module_dir, "/./")) != NULL) { + *p = '\0'; /* Temporary... */ + if (!(module_chdir = normalize_path(module_dir, True, NULL))) + return path_failure(f_out, module_dir, False); + *p = '/'; + if (!(p = normalize_path(p + 2, True, &module_dirlen))) + return path_failure(f_out, strstr(module_dir, "/./"), False); + if (!(full_module_path = normalize_path(module_dir, False, NULL))) + full_module_path = module_dir; + module_dir = p; + } else { + if (!(module_chdir = normalize_path(module_dir, False, NULL))) + return path_failure(f_out, module_dir, False); + full_module_path = module_chdir; + module_dir = "/"; + module_dirlen = 1; + } + } else { + if (!(module_chdir = normalize_path(module_dir, False, &module_dirlen))) + return path_failure(f_out, module_dir, False); + full_module_path = module_dir = module_chdir; + } + set_env_str("RSYNC_MODULE_PATH", full_module_path); + + if (module_dirlen == 1) { + module_dirlen = 0; + set_filter_dir("/", 1); + } else + set_filter_dir(module_dir, module_dirlen); + + p = lp_filter(module_id); + parse_filter_str(&daemon_filter_list, p, rule_template(FILTRULE_WORD_SPLIT), + XFLG_ABS_IF_SLASH | XFLG_DIR2WILD3); + + p = lp_include_from(module_id); + parse_filter_file(&daemon_filter_list, p, rule_template(FILTRULE_INCLUDE), + XFLG_ABS_IF_SLASH | XFLG_DIR2WILD3 | XFLG_OLD_PREFIXES | XFLG_FATAL_ERRORS); + + p = lp_include(module_id); + parse_filter_str(&daemon_filter_list, p, + rule_template(FILTRULE_INCLUDE | FILTRULE_WORD_SPLIT), + XFLG_ABS_IF_SLASH | XFLG_DIR2WILD3 | XFLG_OLD_PREFIXES); + + p = lp_exclude_from(module_id); + parse_filter_file(&daemon_filter_list, p, rule_template(0), + XFLG_ABS_IF_SLASH | XFLG_DIR2WILD3 | XFLG_OLD_PREFIXES | XFLG_FATAL_ERRORS); + + p = lp_exclude(module_id); + parse_filter_str(&daemon_filter_list, p, rule_template(FILTRULE_WORD_SPLIT), + XFLG_ABS_IF_SLASH | XFLG_DIR2WILD3 | XFLG_OLD_PREFIXES); + + log_init(1); + +#if defined HAVE_SETENV || defined HAVE_PUTENV + if ((*lp_early_exec(module_id) || *lp_prexfer_exec(module_id) + || *lp_postxfer_exec(module_id) || *lp_name_converter(module_id)) + && !getenv("RSYNC_NO_XFER_EXEC")) { + set_env_num("RSYNC_PID", (long)getpid()); + + /* For post-xfer exec, fork a new process to run the rsync + * daemon while this process waits for the exit status and + * runs the indicated command at that point. */ + if (*lp_postxfer_exec(module_id)) { + pid_t pid = fork(); + if (pid < 0) { + rsyserr(FLOG, errno, "fork failed"); + io_printf(f_out, "@ERROR: fork failed\n"); + return -1; + } + if (pid) { + int status; + close(f_in); + if (f_out != f_in) + close(f_out); + if (wait_process(pid, &status, 0) < 0) + status = -1; + set_env_num("RSYNC_RAW_STATUS", status); + if (WIFEXITED(status)) + status = WEXITSTATUS(status); + else + status = -1; + set_env_num("RSYNC_EXIT_STATUS", status); + if (shell_exec(lp_postxfer_exec(module_id)) < 0) + status = -1; + _exit(status); + } + } + + /* For early exec, fork a child process to run the indicated + * command and wait for it to exit. */ + if (*lp_early_exec(module_id)) { + int arg_fd; + pid_t pid = start_pre_exec(lp_early_exec(module_id), &arg_fd, NULL); + if (pid == (pid_t)-1) { + rsyserr(FLOG, errno, "early exec preparation failed"); + io_printf(f_out, "@ERROR: early exec preparation failed\n"); + return -1; + } + write_pre_exec_args(arg_fd, NULL, NULL, NULL, 1); + if (finish_pre_exec("early exec", pid, -1) != NULL) { + rsyserr(FLOG, errno, "early exec failed"); + io_printf(f_out, "@ERROR: early exec failed\n"); + return -1; + } + } + + /* For pre-xfer exec, fork a child process to run the indicated + * command, though it first waits for the parent process to + * send us the user's request via a pipe. */ + if (*lp_prexfer_exec(module_id)) { + pre_exec_pid = start_pre_exec(lp_prexfer_exec(module_id), &pre_exec_arg_fd, &pre_exec_error_fd); + if (pre_exec_pid == (pid_t)-1) { + rsyserr(FLOG, errno, "pre-xfer exec preparation failed"); + io_printf(f_out, "@ERROR: pre-xfer exec preparation failed\n"); + return -1; + } + } + + if (*lp_name_converter(module_id)) { + namecvt_pid = start_pre_exec(lp_name_converter(module_id), &namecvt_fd_req, &namecvt_fd_ans); + if (namecvt_pid == (pid_t)-1) { + rsyserr(FLOG, errno, "name-converter exec preparation failed"); + io_printf(f_out, "@ERROR: name-converter exec preparation failed\n"); + return -1; + } + } + } +#endif + + if (early_input) { + free(early_input); + early_input = NULL; + } + + if (use_chroot) { + if (chroot(module_chdir)) { + rsyserr(FLOG, errno, "chroot(\"%s\") failed", module_chdir); + io_printf(f_out, "@ERROR: chroot failed\n"); + return -1; + } + module_chdir = module_dir; + } + + if (!change_dir(module_chdir, CD_NORMAL)) + return path_failure(f_out, module_chdir, True); + if (module_dirlen) + sanitize_paths = 1; + + if ((munge_symlinks = lp_munge_symlinks(module_id)) < 0) + munge_symlinks = !use_chroot || module_dirlen; + if (munge_symlinks) { + STRUCT_STAT st; + char prefix[SYMLINK_PREFIX_LEN]; /* NOT +1 ! */ + strlcpy(prefix, SYMLINK_PREFIX, sizeof prefix); /* trim the trailing slash */ + if (do_stat(prefix, &st) == 0 && S_ISDIR(st.st_mode)) { + rprintf(FLOG, "Symlink munging is unsafe when a %s directory exists.\n", + prefix); + io_printf(f_out, "@ERROR: daemon security issue -- contact admin\n", name); + exit_cleanup(RERR_UNSUPPORTED); + } + } + + if (gid_list.count) { + gid_t *gid_array = gid_list.items; + if (setgid(gid_array[0])) { + rsyserr(FLOG, errno, "setgid %ld failed", (long)gid_array[0]); + io_printf(f_out, "@ERROR: setgid failed\n"); + return -1; + } +#ifdef HAVE_SETGROUPS + /* Set the group(s) we want to be active. */ + if (setgroups(gid_list.count, gid_array)) { + rsyserr(FLOG, errno, "setgroups failed"); + io_printf(f_out, "@ERROR: setgroups failed\n"); + return -1; + } +#endif +#if defined HAVE_INITGROUPS && !defined HAVE_GETGROUPLIST + /* pw is set if the user wants all the user's groups. */ + if (pw && initgroups(pw->pw_name, pw->pw_gid) < 0) { + rsyserr(FLOG, errno, "initgroups failed"); + io_printf(f_out, "@ERROR: initgroups failed\n"); + return -1; + } +#endif + our_gid = MY_GID(); + } + + if (set_uid) { + if (setuid(uid) < 0 +#ifdef HAVE_SETEUID + || seteuid(uid) < 0 +#endif + ) { + rsyserr(FLOG, errno, "setuid %ld failed", (long)uid); + io_printf(f_out, "@ERROR: setuid failed\n"); + return -1; + } + + our_uid = MY_UID(); + am_root = (our_uid == ROOT_UID); + } + + if (lp_temp_dir(module_id) && *lp_temp_dir(module_id)) { + tmpdir = lp_temp_dir(module_id); + if (strlen(tmpdir) >= MAXPATHLEN - 10) { + rprintf(FLOG, + "the 'temp dir' value for %s is WAY too long -- ignoring.\n", + name); + tmpdir = NULL; + } + } + + io_printf(f_out, "@RSYNCD: OK\n"); + + read_args(f_in, name, line, sizeof line, rl_nulls, &argv, &argc, &request); + orig_argv = argv; + + save_munge_symlinks = munge_symlinks; + + reset_output_levels(); /* future verbosity is controlled by client options */ + ret = parse_arguments(&argc, (const char ***) &argv); + if (protect_args && ret) { + orig_early_argv = orig_argv; + protect_args = 2; + read_args(f_in, name, line, sizeof line, 1, &argv, &argc, &request); + orig_argv = argv; + ret = parse_arguments(&argc, (const char ***) &argv); + } else + orig_early_argv = NULL; + + /* The default is to use the user's setting unless the module sets True or False. */ + if (lp_open_noatime(module_id) >= 0) + open_noatime = lp_open_noatime(module_id); + + munge_symlinks = save_munge_symlinks; /* The client mustn't control this. */ + + if (am_daemon > 0) + msgs2stderr = 0; /* A non-rsh-run daemon doesn't have stderr for msgs. */ + + if (pre_exec_pid) { + write_pre_exec_args(pre_exec_arg_fd, request, orig_early_argv, orig_argv, 0); + err_msg = finish_pre_exec("pre-xfer exec", pre_exec_pid, pre_exec_error_fd); + } + + if (namecvt_pid) + write_pre_exec_args(namecvt_fd_req, request, orig_early_argv, orig_argv, 2); + + if (orig_early_argv) + free(orig_early_argv); + + am_server = 1; /* Don't let someone try to be tricky. */ + quiet = 0; + if (lp_ignore_errors(module_id)) + ignore_errors = 1; + if (write_batch < 0) + dry_run = 1; + + if (lp_fake_super(module_id)) { + if (preserve_xattrs > 1) + preserve_xattrs = 1; + am_root = -1; + } else if (am_root < 0) /* Treat --fake-super from client as --super. */ + am_root = 2; + + if (filesfrom_fd == 0) + filesfrom_fd = f_in; + + if (request) { + if (*auth_user) { + rprintf(FLOG, "rsync %s %s from %s@%s (%s)\n", + am_sender ? "on" : "to", + request, auth_user, host, addr); + } else { + rprintf(FLOG, "rsync %s %s from %s (%s)\n", + am_sender ? "on" : "to", + request, host, addr); + } + free(request); + } + +#ifndef DEBUG + /* don't allow the logs to be flooded too fast */ + limit_output_verbosity(lp_max_verbosity(module_id)); +#endif + + if (protocol_version < 23 && (protocol_version == 22 || am_sender)) + io_start_multiplex_out(f_out); + else if (!ret || err_msg) { + /* We have to get I/O multiplexing started so that we can + * get the error back to the client. This means getting + * the protocol setup finished first in later versions. */ + setup_protocol(f_out, f_in); + if (!am_sender) { + /* Since we failed in our option parsing, we may not + * have finished parsing that the client sent us a + * --files-from option, so look for it manually. + * Without this, the socket would be in the wrong + * state for the upcoming error message. */ + if (!files_from) { + int i; + for (i = 0; i < argc; i++) { + if (strncmp(argv[i], "--files-from", 12) == 0) { + files_from = ""; + break; + } + } + } + if (files_from) + write_byte(f_out, 0); + } + io_start_multiplex_out(f_out); + } + + if (!ret || err_msg) { + if (err_msg) { + while ((p = strchr(err_msg, '\n')) != NULL) { + int len = p - err_msg + 1; + rwrite(FERROR, err_msg, len, 0); + err_msg += len; + } + if (*err_msg) + rprintf(FERROR, "%s\n", err_msg); + io_flush(MSG_FLUSH); + } else + option_error(); + msleep(400); + exit_cleanup(RERR_UNSUPPORTED); + } + +#ifdef ICONV_OPTION + if (!iconv_opt) { + if (ic_send != (iconv_t)-1) { + iconv_close(ic_send); + ic_send = (iconv_t)-1; + } + if (ic_recv != (iconv_t)-1) { + iconv_close(ic_recv); + ic_recv = (iconv_t)-1; + } + } +#endif + + if (!numeric_ids + && (use_chroot ? lp_numeric_ids(module_id) != False && !*lp_name_converter(module_id) + : lp_numeric_ids(module_id) == True)) + numeric_ids = -1; /* Set --numeric-ids w/o breaking protocol. */ + + if (lp_timeout(module_id) && (!io_timeout || lp_timeout(module_id) < io_timeout)) + set_io_timeout(lp_timeout(module_id)); + + /* If we have some incoming/outgoing chmod changes, append them to + * any user-specified changes (making our changes have priority). + * We also get a pointer to just our changes so that a receiver + * process can use them separately if --perms wasn't specified. */ + if (am_sender) + p = lp_outgoing_chmod(module_id); + else + p = lp_incoming_chmod(module_id); + if (*p && !(daemon_chmod_modes = parse_chmod(p, &chmod_modes))) { + rprintf(FLOG, "Invalid \"%sing chmod\" directive: %s\n", + am_sender ? "outgo" : "incom", p); + } + + start_server(f_in, f_out, argc, argv); + + return 0; +} + +BOOL namecvt_call(const char *cmd, const char **name_p, id_t *id_p) +{ + char buf[1024]; + int got, len; + + if (*name_p) + len = snprintf(buf, sizeof buf, "%s %s\n", cmd, *name_p); + else + len = snprintf(buf, sizeof buf, "%s %ld\n", cmd, (long)*id_p); + if (len >= (int)sizeof buf) { + rprintf(FERROR, "namecvt_call() request was too large.\n"); + exit_cleanup(RERR_UNSUPPORTED); + } + + while ((got = write(namecvt_fd_req, buf, len)) != len) { + if (got < 0 && errno == EINTR) + continue; + rprintf(FERROR, "Connection to name-converter failed.\n"); + exit_cleanup(RERR_SOCKETIO); + } + + if (!read_line_old(namecvt_fd_ans, buf, sizeof buf, 0)) + return False; + + if (*name_p) + *id_p = (id_t)atol(buf); + else + *name_p = strdup(buf); + + return True; +} + +/* send a list of available modules to the client. Don't list those + with "list = False". */ +static void send_listing(int fd) +{ + int n = lp_num_modules(); + int i; + + for (i = 0; i < n; i++) { + if (lp_list(i)) + io_printf(fd, "%-15s\t%s\n", lp_name(i), lp_comment(i)); + } + + if (protocol_version >= 25) + io_printf(fd,"@RSYNCD: EXIT\n"); +} + +static int load_config(int globals_only) +{ + if (!config_file) { + if (am_daemon < 0 && am_root <= 0) + config_file = RSYNCD_USERCONF; + else + config_file = RSYNCD_SYSCONF; + } + return lp_load(config_file, globals_only); +} + +/* 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 */ +int start_daemon(int f_in, int f_out) +{ + char line[1024]; + const char *addr, *host; + char *p; + int i; + + /* At this point, am_server is only set for a daemon started via rsh. + * Because am_server gets forced on soon, we'll set am_daemon to -1 as + * a flag that can be checked later on to distinguish a normal daemon + * from an rsh-run daemon. */ + if (am_server) + am_daemon = -1; + + io_set_sock_fds(f_in, f_out); + + /* We must load the config file before calling any function that + * might cause log-file output to occur. This ensures that the + * "log file" param gets honored for the 2 non-forked use-cases + * (when rsync is run by init and run by a remote shell). */ + if (!load_config(0)) + exit_cleanup(RERR_SYNTAX); + + if (lp_proxy_protocol() && !read_proxy_protocol_header(f_in)) + return -1; + + p = lp_daemon_chroot(); + if (*p) { + log_init(0); /* Make use we've initialized syslog before chrooting. */ + if (chroot(p) < 0) { + rsyserr(FLOG, errno, "daemon chroot(\"%s\") failed", p); + return -1; + } + if (chdir("/") < 0) { + rsyserr(FLOG, errno, "daemon chdir(\"/\") failed"); + return -1; + } + } + p = lp_daemon_gid(); + if (*p) { + gid_t gid; + if (!group_to_gid(p, &gid, True)) { + rprintf(FLOG, "Invalid daemon gid: %s\n", p); + return -1; + } + if (setgid(gid) < 0) { + rsyserr(FLOG, errno, "Unable to set group to daemon gid %ld", (long)gid); + return -1; + } + our_gid = MY_GID(); + } + p = lp_daemon_uid(); + if (*p) { + uid_t uid; + if (!user_to_uid(p, &uid, True)) { + rprintf(FLOG, "Invalid daemon uid: %s\n", p); + return -1; + } + if (setuid(uid) < 0) { + rsyserr(FLOG, errno, "Unable to set user to daemon uid %ld", (long)uid); + return -1; + } + our_uid = MY_UID(); + am_root = (our_uid == ROOT_UID); + } + + addr = client_addr(f_in); + host = lp_reverse_lookup(-1) ? client_name(addr) : undetermined_hostname; + rprintf(FLOG, "connect from %s (%s)\n", host, addr); + + if (am_daemon > 0) { + set_socket_options(f_in, "SO_KEEPALIVE"); + set_nonblocking(f_in); + } + + if (exchange_protocols(f_in, f_out, line, sizeof line, 0) < 0) + return -1; + + line[0] = 0; + if (!read_line_old(f_in, line, sizeof line, 0)) + return -1; + + if (strncmp(line, EARLY_INPUT_CMD, EARLY_INPUT_CMDLEN) == 0) { + early_input_len = strtol(line + EARLY_INPUT_CMDLEN, NULL, 10); + if (early_input_len <= 0 || early_input_len > BIGPATHBUFLEN) { + io_printf(f_out, "@ERROR: invalid early_input length\n"); + return -1; + } + early_input = new_array(char, early_input_len); + read_buf(f_in, early_input, early_input_len); + + if (!read_line_old(f_in, line, sizeof line, 0)) + return -1; + } + + if (!*line || strcmp(line, "#list") == 0) { + rprintf(FLOG, "module-list request from %s (%s)\n", + host, addr); + send_listing(f_out); + return -1; + } + + if (*line == '#') { + /* it's some sort of command that I don't understand */ + io_printf(f_out, "@ERROR: Unknown command '%s'\n", line); + return -1; + } + + if ((i = lp_number(line)) < 0) { + rprintf(FLOG, "unknown module '%s' tried from %s (%s)\n", + line, host, addr); + io_printf(f_out, "@ERROR: Unknown module '%s'\n", line); + return -1; + } + +#ifdef HAVE_SIGACTION + sigact.sa_flags = SA_NOCLDSTOP; +#endif + SIGACTION(SIGCHLD, remember_children); + + return rsync_module(f_in, f_out, i, addr, host); +} + +static void create_pid_file(void) +{ + char *pid_file = lp_pid_file(); + char pidbuf[32]; + STRUCT_STAT st1, st2; + char *fail = NULL; + + if (!pid_file || !*pid_file) + return; + +#ifdef O_NOFOLLOW +#define SAFE_OPEN_FLAGS (O_CREAT|O_NOFOLLOW) +#else +#define SAFE_OPEN_FLAGS (O_CREAT) +#endif + + /* These tests make sure that a temp-style lock dir is handled safely. */ + st1.st_mode = 0; + if (do_lstat(pid_file, &st1) == 0 && !S_ISREG(st1.st_mode) && unlink(pid_file) < 0) + fail = "unlink"; + else if ((pid_file_fd = do_open(pid_file, O_RDWR|SAFE_OPEN_FLAGS, 0664)) < 0) + fail = S_ISREG(st1.st_mode) ? "open" : "create"; + else if (!lock_range(pid_file_fd, 0, 4)) + fail = "lock"; + else if (do_fstat(pid_file_fd, &st1) < 0) + fail = "fstat opened"; + else if (st1.st_size > (int)sizeof pidbuf) + fail = "find small"; + else if (do_lstat(pid_file, &st2) < 0) + fail = "lstat"; + else if (!S_ISREG(st1.st_mode)) + fail = "avoid file overwrite race for"; + else if (st1.st_dev != st2.st_dev || st1.st_ino != st2.st_ino) + fail = "verify stat info for"; +#ifdef HAVE_FTRUNCATE + else if (do_ftruncate(pid_file_fd, 0) < 0) + fail = "truncate"; +#endif + else { + pid_t pid = getpid(); + int len = snprintf(pidbuf, sizeof pidbuf, "%d\n", (int)pid); +#ifndef HAVE_FTRUNCATE + /* What can we do with a too-long file and no truncate? I guess we'll add extra newlines. */ + while (len < st1.st_size) /* We already verified that st_size chars fits in the buffer. */ + pidbuf[len++] = '\n'; + /* We don't need the buffer to end in a '\0' (and we may not have room to add it). */ +#endif + if (write(pid_file_fd, pidbuf, len) != len) + fail = "write"; + cleanup_set_pid(pid); /* Mark the file for removal on exit, even if the write failed. */ + } + + if (fail) { + char msg[1024]; + snprintf(msg, sizeof msg, "failed to %s pid file %s: %s\n", + fail, pid_file, strerror(errno)); + fputs(msg, stderr); + rprintf(FLOG, "%s", msg); + exit_cleanup(RERR_FILEIO); + } + + /* The file is left open so that the lock remains valid. It is closed in our forked child procs. */ +} + +/* Become a daemon, discarding the controlling terminal. */ +static void become_daemon(void) +{ + int i; + pid_t pid = fork(); + + if (pid) { + if (pid < 0) { + fprintf(stderr, "failed to fork: %s\n", strerror(errno)); + exit_cleanup(RERR_FILEIO); + } + _exit(0); + } + + create_pid_file(); + + /* detach from the terminal */ +#ifdef HAVE_SETSID + setsid(); +#elif defined TIOCNOTTY + i = open("/dev/tty", O_RDWR); + if (i >= 0) { + ioctl(i, (int)TIOCNOTTY, (char *)0); + close(i); + } +#endif + /* make sure that stdin, stdout an stderr don't stuff things + * up (library functions, for example) */ + for (i = 0; i < 3; i++) { + close(i); + open("/dev/null", O_RDWR); + } +} + +int daemon_main(void) +{ + 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 */ + for (i = 1; i < 3; i++) { + close(i); + open("/dev/null", O_RDWR); + } + + return start_daemon(STDIN_FILENO, STDIN_FILENO); + } + + if (!load_config(1)) { + fprintf(stderr, "Failed to parse config file: %s\n", config_file); + exit_cleanup(RERR_SYNTAX); + } + set_dparams(0); + + if (no_detach) + create_pid_file(); + else + become_daemon(); + + if (rsync_port == 0 && (rsync_port = lp_rsync_port()) == 0) + rsync_port = RSYNC_PORT; + if (bind_address == NULL && *lp_bind_address()) + bind_address = lp_bind_address(); + + log_init(0); + + rprintf(FLOG, "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 getnameinfo on the + * local address??? */ + + start_accept_loop(rsync_port, start_daemon); + return -1; +} |