From 50ad3f2a895c38f8d546f87490ca96ab7d9e011e Mon Sep 17 00:00:00 2001 From: Scott Lamb Date: Wed, 7 Nov 2007 02:48:33 +0000 Subject: [PATCH] Fancier protocol for control socket * pass error status back * pass message boundaries --- src/control.c | 64 ++++++++++++++++++-- src/control_common.h | 46 +++++++++++++++ src/tincctl.c | 135 ++++++++++++++++++++++++++++++++++++++++--- 3 files changed, 232 insertions(+), 13 deletions(-) create mode 100644 src/control_common.h diff --git a/src/control.c b/src/control.c index b3cce928..7b27f69a 100644 --- a/src/control.c +++ b/src/control.c @@ -24,6 +24,7 @@ #include "system.h" #include "conf.h" #include "control.h" +#include "control_common.h" #include "logger.h" #include "xalloc.h" @@ -33,17 +34,58 @@ static splay_tree_t *control_socket_tree; extern char *controlsocketname; static void handle_control_data(struct bufferevent *event, void *data) { - char *line = evbuffer_readline(event->input); - if(!line) + tinc_ctl_request_t req; + size_t size; + tinc_ctl_request_t res; + struct evbuffer *res_data = NULL; + + if(EVBUFFER_LENGTH(event->input) < sizeof(tinc_ctl_request_t)) return; - - if(!strcasecmp(line, "stop")) { + + /* Copy the structure to ensure alignment */ + memcpy(&req, EVBUFFER_DATA(event->input), sizeof(tinc_ctl_request_t)); + + if(EVBUFFER_LENGTH(event->input) < req.length) + return; + + if(req.length < sizeof(tinc_ctl_request_t)) + goto failure; + + memset(&res, 0, sizeof res); + res.type = req.type; + res.id = req.id; + + res_data = evbuffer_new(); + if (res_data == NULL) { + res.res_errno = ENOMEM; + goto respond; + } + + if(req.type == REQ_STOP) { logger(LOG_NOTICE, _("Got stop command")); event_loopexit(NULL); - return; + goto respond; } logger(LOG_DEBUG, _("Malformed control command received")); + res.res_errno = EINVAL; + +respond: + res.length = (sizeof res) + + ((res_data == NULL) ? 0 : EVBUFFER_LENGTH(res_data)); + evbuffer_drain(event->input, req.length); + if(bufferevent_write(event, &res, sizeof res) == -1) + goto failure; + if(res_data != NULL) { + if(bufferevent_write_buffer(event, res_data) == -1) + goto failure; + evbuffer_free(res_data); + } + return; + +failure: + logger(LOG_INFO, _("Closing control socket on error")); + evbuffer_free(res_data); close(event->ev_read.ev_fd); splay_delete(control_socket_tree, event); } @@ -61,6 +103,7 @@ static void handle_control_error(struct bufferevent *event, short what, void *da static void handle_new_control_socket(int fd, short events, void *data) { int newfd; struct bufferevent *ev; + tinc_ctl_greeting_t greeting; newfd = accept(fd, NULL, NULL); @@ -77,6 +120,17 @@ static void handle_new_control_socket(int fd, short events, void *data) { return; } + memset(&greeting, 0, sizeof greeting); + greeting.version = TINC_CTL_VERSION_CURRENT; + if(bufferevent_write(ev, &greeting, sizeof greeting) == -1) { + logger(LOG_ERR, + _("Cannot send greeting for new control connection: %s"), + strerror(errno)); + bufferevent_free(ev); + close(newfd); + return; + } + bufferevent_enable(ev, EV_READ); splay_insert(control_socket_tree, ev); diff --git a/src/control_common.h b/src/control_common.h new file mode 100644 index 00000000..3fa034eb --- /dev/null +++ b/src/control_common.h @@ -0,0 +1,46 @@ +/* + control_protocol.h -- control socket protocol. + Copyright (C) 2007 Scott Lamb + + 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. + + $Id$ +*/ + +#ifndef __TINC_CONTROL_PROTOCOL_H__ +#define __TINC_CONTROL_PROTOCOL_H__ + +enum request_type { + REQ_STOP, + REQ_RELOAD, + REQ_RESTART, +}; + +#define TINC_CTL_VERSION_CURRENT 0 + +/* This greeting is sent by the server on socket open. */ +typedef struct tinc_ctl_greeting_t { + int version; +} tinc_ctl_greeting_t; + +/* A single request or response header. */ +typedef struct tinc_ctl_request_t { + size_t length; /* total length, including the header */ + enum request_type type; + int id; + int res_errno; /* used only for responses */ +} tinc_ctl_request_t; + +#endif diff --git a/src/tincctl.c b/src/tincctl.c index 5d65f3aa..3944fa2e 100644 --- a/src/tincctl.c +++ b/src/tincctl.c @@ -30,8 +30,9 @@ #include -#include "protocol.h" #include "xalloc.h" +#include "protocol.h" +#include "control_common.h" /* The name this program was run with. */ char *program_name = NULL; @@ -327,9 +328,118 @@ static void make_names(void) { } } +static int fullread(int fd, void *data, size_t datalen) { + int rv, len = 0; + + while (len < datalen) { + rv = read(fd, data + len, datalen - len); + if(rv == -1 && errno == EINTR) + continue; + else if (rv == -1) + return rv; + else if (rv == 0) { + errno = ENODATA; + return -1; + } + len += rv; + } + return 0; +} + +/* + Send a request (raw) +*/ +static int send_ctl_request(int fd, enum request_type type, + void const *outdata, size_t outdatalen, + int *res_errno_p, void **indata_p, + size_t *indatalen_p) { + tinc_ctl_request_t req; + int rv; + struct iovec vector[2] = { + {&req, sizeof(req)}, + {(void*) outdata, outdatalen} + }; + void *indata; + + if(res_errno_p == NULL) + return -1; + + memset(&req, 0, sizeof req); + req.length = sizeof req + outdatalen; + req.type = type; + req.res_errno = 0; + + while((rv = writev(fd, vector, 2)) == -1 && errno == EINTR) ; + if(rv != req.length) + return -1; + + if(fullread(fd, &req, sizeof req) == -1) + return -1; + + if(req.length < sizeof req) { + errno = EINVAL; + return -1; + } + + if(req.length > sizeof req) { + if (indata_p == NULL) { + errno = EINVAL; + return -1; + } + + indata = xmalloc(req.length - sizeof req); + + if(fullread(fd, indata, req.length - sizeof req) == -1) { + free(indata); + return -1; + } + + *indata_p = indata; + if(indatalen_p != NULL) + *indatalen_p = req.length - sizeof req; + } + + *res_errno_p = req.res_errno; + + return 0; +} + +/* + Send a request (with printfs) +*/ +static int send_ctl_request_cooked(int fd, enum request_type type, + void const *outdata, size_t outdatalen) +{ + int res_errno = -1; + char *buf = NULL; + size_t buflen = 0; + + if(send_ctl_request(fd, type, outdata, outdatalen, &res_errno, + (void**) &buf, &buflen)) { + fprintf(stderr, _("Error sending request: %s\n"), strerror(errno)); + return -1; + } + + if(buf != NULL) { + printf("%*s", buflen, buf); + free(buf); + } + + if(res_errno != 0) { + fprintf(stderr, _("Server reported error: %s\n"), strerror(res_errno)); + return -1; + } + + return 0; +} + int main(int argc, char *argv[], char *envp[]) { - int fd; struct sockaddr_un addr; + int fd; + int len; + tinc_ctl_greeting_t greeting; + tinc_ctl_request_t req; + program_name = argv[0]; setlocale(LC_ALL, ""); @@ -399,6 +509,18 @@ int main(int argc, char *argv[], char *envp[]) { return 1; } + if(fullread(fd, &greeting, sizeof greeting) == -1) { + fprintf(stderr, _("Cannot read greeting from control socket: %s\n"), + strerror(errno)); + return 1; + } + + if(greeting.version != TINC_CTL_VERSION_CURRENT) { + fprintf(stderr, _("Version mismatch: server %d, client %d\n"), + greeting.version, TINC_CTL_VERSION_CURRENT); + return 1; + } + struct ucred cred; socklen_t credlen = sizeof cred; @@ -413,18 +535,15 @@ int main(int argc, char *argv[], char *envp[]) { } if(!strcasecmp(argv[optind], "stop")) { - write(fd, "stop\n", 5); - return 0; + return send_ctl_request_cooked(fd, REQ_STOP, NULL, 0) != -1; } if(!strcasecmp(argv[optind], "reload")) { - write(fd, "reload\n", 7); - return 0; + return send_ctl_request_cooked(fd, REQ_RELOAD, NULL, 0) != -1; } if(!strcasecmp(argv[optind], "restart")) { - write(fd, "restart\n", 8); - return 0; + return send_ctl_request_cooked(fd, REQ_RESTART, NULL, 0) != -1; } fprintf(stderr, _("Unknown command `%s'.\n"), argv[optind]); -- 2.20.1