/* protocol.c -- handle the meta-protocol, basic functions Copyright (C) 1999-2001 Ivo Timmermans , 2000,2001 Guus Sliepen 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: protocol.c,v 1.28.4.126 2002/03/22 13:31:18 guus Exp $ */ #include "config.h" #include #include #include #include #include #include #include #include #include #include "conf.h" #include "protocol.h" #include "meta.h" #include "connection.h" #include "system.h" avl_tree_t *past_request_tree; int check_id(char *id) { int i; for (i = 0; i < strlen(id); i++) if(!isalnum(id[i]) && id[i] != '_') return -1; return 0; } /* Generic request routines - takes care of logging and error detection as well */ int send_request(connection_t *c, const char *format, ...) { va_list args; char buffer[MAXBUFSIZE]; int len, request; cp /* Use vsnprintf instead of vasprintf: faster, no memory fragmentation, cleanup is automatic, and there is a limit on the input buffer anyway */ va_start(args, format); len = vsnprintf(buffer, MAXBUFSIZE, format, args); va_end(args); if(len < 0 || len > MAXBUFSIZE-1) { syslog(LOG_ERR, _("Output buffer overflow while sending request to %s (%s)"), c->name, c->hostname); return -1; } if(debug_lvl >= DEBUG_PROTOCOL) { sscanf(buffer, "%d", &request); if(debug_lvl >= DEBUG_META) syslog(LOG_DEBUG, _("Sending %s to %s (%s): %s"), request_name[request], c->name, c->hostname, buffer); else syslog(LOG_DEBUG, _("Sending %s to %s (%s)"), request_name[request], c->name, c->hostname); } buffer[len++] = '\n'; cp return send_meta(c, buffer, len); } int receive_request(connection_t *c) { int request; cp if(sscanf(c->buffer, "%d", &request) == 1) { if((request < 0) || (request >= LAST) || (request_handlers[request] == NULL)) { if(debug_lvl >= DEBUG_META) syslog(LOG_DEBUG, _("Unknown request from %s (%s): %s"), c->name, c->hostname, c->buffer); else syslog(LOG_ERR, _("Unknown request from %s (%s)"), c->name, c->hostname); return -1; } else { if(debug_lvl >= DEBUG_PROTOCOL) { if(debug_lvl >= DEBUG_META) syslog(LOG_DEBUG, _("Got %s from %s (%s): %s"), request_name[request], c->name, c->hostname, c->buffer); else syslog(LOG_DEBUG, _("Got %s from %s (%s)"), request_name[request], c->name, c->hostname); } } if((c->allow_request != ALL) && (c->allow_request != request)) { syslog(LOG_ERR, _("Unauthorized request from %s (%s)"), c->name, c->hostname); return -1; } if(request_handlers[request](c)) /* Something went wrong. Probably scriptkiddies. Terminate. */ { syslog(LOG_ERR, _("Error while processing %s from %s (%s)"), request_name[request], c->name, c->hostname); return -1; } } else { syslog(LOG_ERR, _("Bogus data received from %s (%s)"), c->name, c->hostname); return -1; } cp return 0; } int request_compare(past_request_t *a, past_request_t *b) { cp return strcmp(a->request, b->request); } void init_requests(void) { cp past_request_tree = avl_alloc_tree((avl_compare_t)request_compare, (avl_action_t)free); cp } void exit_requests(void) { cp avl_delete_tree(past_request_tree); cp } int seen_request(char *request) { past_request_t p, *new; cp p.request = request; if(avl_search(past_request_tree, &p)) { if(debug_lvl >= DEBUG_SCARY_THINGS) syslog(LOG_DEBUG, _("Already seen request")); return 1; } else { new = (past_request_t *)xmalloc(sizeof(*new)); new->request = xstrdup(request); new->firstseen = now; avl_insert(past_request_tree, new); return 0; } cp } void age_past_requests(void) { avl_node_t *node, *next; past_request_t *p; int left = 0, deleted = 0; cp for(node = past_request_tree->head; node; node = next) { next = node->next; p = (past_request_t *)node->data; if(p->firstseen + pingtimeout < now) avl_delete_node(past_request_tree, node), deleted++; else left++; } if(debug_lvl >= DEBUG_SCARY_THINGS && left + deleted) syslog(LOG_DEBUG, _("Aging past requests: deleted %d, left %d\n"), deleted, left); cp } /* Jumptable for the request handlers */ int (*request_handlers[])(connection_t*) = { id_h, metakey_h, challenge_h, chal_reply_h, ack_h, status_h, error_h, termreq_h, ping_h, pong_h, // add_node_h, del_node_h, add_subnet_h, del_subnet_h, add_edge_h, del_edge_h, key_changed_h, req_key_h, ans_key_h, tcppacket_h, }; /* Request names */ char (*request_name[]) = { "ID", "METAKEY", "CHALLENGE", "CHAL_REPLY", "ACK", "STATUS", "ERROR", "TERMREQ", "PING", "PONG", // "ADD_NODE", "DEL_NODE", "ADD_SUBNET", "DEL_SUBNET", "ADD_EDGE", "DEL_EDGE", "KEY_CHANGED", "REQ_KEY", "ANS_KEY", "PACKET", };