From 7909e65f8307f0e0a632275d4d895cf95f3de039 Mon Sep 17 00:00:00 2001 From: Wayne Davison Date: Sun, 9 Sep 2007 07:53:05 +0000 Subject: [PATCH] - Made start_socket_client() and start_inband_exchange() take a variable number of remote args. - We now exchange a "VERSION.SUBVERSION" value in the initial @RSYNCD message. This is backward compatible with pre-protocol 30 rsyncs, and fixes a problem where rsync daemons weren't checking if they were speaking a compatible pre-release protocol. - Moved the protocol-handling code (which was in two places) into a new function: exchange_protocols(). - Protocol 30 now sends/receives the daemon args using NULLs as a separator rather than a newline. - Moved the arg-reading code into a new function in io.c: read_args(). --- clientserver.c | 229 ++++++++++++++++++++++++++----------------------- 1 file changed, 120 insertions(+), 109 deletions(-) diff --git a/clientserver.c b/clientserver.c index 6d1da3e8..d34f2b25 100644 --- a/clientserver.c +++ b/clientserver.c @@ -63,6 +63,8 @@ struct chmod_mode_struct *daemon_chmod_modes; char *module_dir = NULL; unsigned int module_dirlen = 0; +static int rl_nulls = 0; + #ifdef HAVE_SIGACTION static struct sigaction sigact; #endif @@ -81,7 +83,8 @@ static struct sigaction sigact; * @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 start_socket_client(char *host, int remote_argc, char *remote_argv[], + int argc, char *argv[]) { int fd, ret; char *p, *user = NULL; @@ -89,7 +92,7 @@ int start_socket_client(char *host, char *path, int argc, char *argv[]) /* 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 (*path == '/') { + if (**remote_argv == '/') { rprintf(FERROR, "ERROR: The remote path must start with a module name not a /\n"); return -1; @@ -108,19 +111,92 @@ int start_socket_client(char *host, char *path, int argc, char *argv[]) set_socket_options(fd, sockopts); - ret = start_inband_exchange(user, path, fd, fd, argc); + ret = start_inband_exchange(fd, fd, user, remote_argc, remote_argv); return ret ? ret : client_run(fd, fd, -1, argc, argv); } -int start_inband_exchange(const char *user, char *path, int f_in, int f_out, - int argc) +static int exchange_protocols(int f_in, int f_out, char *buf, size_t bufsiz, int am_client) +{ + int remote_sub = -1; +#if SUBPROTOCOL_VERSION != 0 + int our_sub = protocol_version < PROTOCOL_VERSION ? 0 : SUBPROTOCOL_VERSION; +#else + int our_sub = 0; +#endif + char *motd; + + io_printf(f_out, "@RSYNCD: %d.%d\n", protocol_version, our_sub); + + if (!am_client) { + 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)) { + 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: server is speaking an incompatible beta of protocol 30\n"); + else + io_printf(f_out, "@ERROR: your client is speaking an incompatible beta of protocol 30\n"); + return -1; + } + remote_sub = 0; + } + + 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; + char line[BIGPATHBUFLEN]; char *sargs[MAX_ARGS]; int sargc = 0; - char line[BIGPATHBUFLEN]; - char *p; + char *p, *path = *argv; if (argc == 0 && !am_sender) list_only |= 1; @@ -136,21 +212,8 @@ int start_inband_exchange(const char *user, char *path, int f_in, int f_out, if (!user) user = getenv("LOGNAME"); - io_printf(f_out, "@RSYNCD: %d\n", protocol_version); - - if (!read_line(f_in, line, sizeof line - 1)) { - rprintf(FERROR, "rsync: did not see server greeting\n"); + if (exchange_protocols(f_in, f_out, line, sizeof line, 1) < 0) return -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; if (list_only && protocol_version >= 29) list_only |= 2; @@ -161,18 +224,28 @@ int start_inband_exchange(const char *user, char *path, int f_in, int f_out, daemon_over_rsh = 0; server_options(sargs, &sargc); + if (sargc >= MAX_ARGS - 2) + goto arg_overflow; + sargs[sargc++] = "."; - if (path && *path) - sargs[sargc++] = path; + while (argc > 0) { + if (sargc >= MAX_ARGS - 1) { + arg_overflow: + rprintf(FERROR, "internal: args[] overflowed in do_cmd()\n"); + exit_cleanup(RERR_SYNTAX); + } + sargs[sargc++] = *argv++; + argc--; + } sargs[sargc] = NULL; if (verbose > 1) print_child_argv(sargs); - p = strchr(path,'/'); - if (p) *p = 0; + p = strchr(path, '/'); + if (p) *p = '\0'; io_printf(f_out, "%s\n", path); if (p) *p = '/'; @@ -181,7 +254,7 @@ int start_inband_exchange(const char *user, char *path, int f_in, int f_out, kluge_around_eof = list_only && protocol_version < 25 ? 1 : 0; while (1) { - if (!read_line(f_in, line, sizeof line - 1)) { + if (!read_line_old(f_in, line, sizeof line)) { rprintf(FERROR, "rsync: didn't get server startup line\n"); return -1; } @@ -216,10 +289,17 @@ int start_inband_exchange(const char *user, char *path, int f_in, int f_out, } kluge_around_eof = 0; - for (i = 0; i < sargc; i++) { - io_printf(f_out, "%s\n", sargs[i]); + if (rl_nulls) { + for (i = 0; i < sargc; i++) { + 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"); } - io_printf(f_out, "\n"); if (protocol_version < 23) { if (protocol_version == 22 || !am_sender) @@ -234,12 +314,12 @@ static char *finish_pre_exec(pid_t pid, int fd, char *request, { int j, status = -1; - if (request) { - write_buf(fd, request, strlen(request)+1); - for (j = 0; j < argc; j++) - write_buf(fd, argv[j], strlen(argv[j])+1); - } + if (!request) + request = "(NONE)"; + write_buf(fd, request, strlen(request)+1); + for (j = 0; j < argc; j++) + write_buf(fd, argv[j], strlen(argv[j])+1); write_byte(fd, 0); close(fd); @@ -275,8 +355,7 @@ static int read_arg_from_pipe(int fd, char *buf, int limit) static int rsync_module(int f_in, int f_out, int i, char *addr, char *host) { - int argc = 0; - int maxargs; + int argc, opt_cnt; char **argv; char line[BIGPATHBUFLEN]; uid_t uid = (uid_t)-2; /* canonically "nobody" */ @@ -284,7 +363,6 @@ static int rsync_module(int f_in, int f_out, int i, char *addr, char *host) char *p, *err_msg = NULL; char *name = lp_name(i); int use_chroot = lp_use_chroot(i); - int start_glob = 0; int ret, pre_exec_fd = -1; pid_t pre_exec_pid = 0; char *request = NULL; @@ -580,54 +658,11 @@ static int rsync_module(int f_in, int f_out, int i, char *addr, char *host) io_printf(f_out, "@RSYNCD: OK\n"); - maxargs = MAX_ARGS; - if (!(argv = new_array(char *, maxargs))) - out_of_memory("rsync_module"); - argv[argc++] = "rsyncd"; - - while (1) { - if (!read_line(f_in, line, sizeof line - 1)) - return -1; - - if (!*line) - break; - - p = line; - - if (argc == maxargs) { - maxargs += MAX_ARGS; - if (!(argv = realloc_array(argv, char *, maxargs))) - out_of_memory("rsync_module"); - } - if (!(argv[argc] = strdup(p))) - out_of_memory("rsync_module"); - - switch (start_glob) { - case 0: - argc++; - if (strcmp(line, ".") == 0) - start_glob = 1; - break; - case 1: - if (pre_exec_pid) { - err_msg = finish_pre_exec(pre_exec_pid, - pre_exec_fd, p, - argc, argv); - pre_exec_pid = 0; - } - request = strdup(p); - start_glob = 2; - /* FALL THROUGH */ - default: - if (!err_msg) - glob_expand(name, &argv, &argc, &maxargs); - break; - } - } + opt_cnt = read_args(f_in, name, line, sizeof line, rl_nulls, &argv, &argc, &request); if (pre_exec_pid) { err_msg = finish_pre_exec(pre_exec_pid, pre_exec_fd, request, - argc, argv); + opt_cnt, argv); } verbose = 0; /* future verbosity is controlled by client options */ @@ -744,7 +779,7 @@ static void send_listing(int fd) int start_daemon(int f_in, int f_out) { char line[1024]; - char *motd, *addr, *host; + char *addr, *host; int i; io_set_sock_fds(f_in, f_out); @@ -769,35 +804,11 @@ int start_daemon(int f_in, int f_out) set_nonblocking(f_in); } - io_printf(f_out, "@RSYNCD: %d\n", protocol_version); - - motd = lp_motd_file(); - if (motd && *motd) { - FILE *f = fopen(motd,"r"); - while (f && !feof(f)) { - int len = fread(line, 1, sizeof line - 1, f); - if (len > 0) { - line[len] = 0; - io_printf(f_out, "%s", line); - } - } - if (f) - fclose(f); - io_printf(f_out, "\n"); - } - - if (!read_line(f_in, line, sizeof line - 1)) + if (exchange_protocols(f_in, f_out, line, sizeof line, 0) < 0) return -1; - 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; - line[0] = 0; - if (!read_line(f_in, line, sizeof line - 1)) + if (!read_line_old(f_in, line, sizeof line)) return -1; if (!*line || strcmp(line, "#list") == 0) { -- 2.34.1