1*205f2136Sderaadt /* $OpenBSD: table.c,v 1.15 2014/10/08 02:10:05 deraadt Exp $ */ 2ebad6d3cSmickey 3df930be7Sderaadt /* 4df930be7Sderaadt * Copyright (c) 1983 Regents of the University of California. 5df930be7Sderaadt * All rights reserved. 6df930be7Sderaadt * 7df930be7Sderaadt * Redistribution and use in source and binary forms, with or without 8df930be7Sderaadt * modification, are permitted provided that the following conditions 9df930be7Sderaadt * are met: 10df930be7Sderaadt * 1. Redistributions of source code must retain the above copyright 11df930be7Sderaadt * notice, this list of conditions and the following disclaimer. 12df930be7Sderaadt * 2. Redistributions in binary form must reproduce the above copyright 13df930be7Sderaadt * notice, this list of conditions and the following disclaimer in the 14df930be7Sderaadt * documentation and/or other materials provided with the distribution. 15e33d3bd3Smillert * 3. Neither the name of the University nor the names of its contributors 16df930be7Sderaadt * may be used to endorse or promote products derived from this software 17df930be7Sderaadt * without specific prior written permission. 18df930be7Sderaadt * 19df930be7Sderaadt * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20df930be7Sderaadt * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21df930be7Sderaadt * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22df930be7Sderaadt * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23df930be7Sderaadt * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24df930be7Sderaadt * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25df930be7Sderaadt * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26df930be7Sderaadt * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27df930be7Sderaadt * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28df930be7Sderaadt * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29df930be7Sderaadt * SUCH DAMAGE. 30df930be7Sderaadt */ 31df930be7Sderaadt 32df930be7Sderaadt /* 33df930be7Sderaadt * Routines to handle insertion, deletion, etc on the table 34df930be7Sderaadt * of requests kept by the daemon. Nothing fancy here, linear 35df930be7Sderaadt * search on a double-linked list. A time is kept with each 36df930be7Sderaadt * entry so that overly old invitations can be eliminated. 37df930be7Sderaadt * 38df930be7Sderaadt * Consider this a mis-guided attempt at modularity 39df930be7Sderaadt */ 40df930be7Sderaadt #include <sys/param.h> 41df930be7Sderaadt #include <sys/time.h> 42df930be7Sderaadt #include <sys/socket.h> 43e4de0f9aSmickey #include <sys/queue.h> 44df930be7Sderaadt #include <protocols/talkd.h> 45df930be7Sderaadt #include <syslog.h> 46df930be7Sderaadt #include <unistd.h> 47df930be7Sderaadt #include <stdio.h> 48df930be7Sderaadt #include <stdlib.h> 49df930be7Sderaadt #include <string.h> 50ebad6d3cSmickey #include "talkd.h" 51df930be7Sderaadt 52df930be7Sderaadt #define MAX_ID 16000 /* << 2^15 so I don't have sign troubles */ 53df930be7Sderaadt 54df930be7Sderaadt struct timeval tp; 55df930be7Sderaadt struct timezone txp; 56df930be7Sderaadt 57df930be7Sderaadt typedef struct table_entry TABLE_ENTRY; 58df930be7Sderaadt 59df930be7Sderaadt struct table_entry { 60df930be7Sderaadt CTL_MSG request; 61e4de0f9aSmickey time_t time; 62e4de0f9aSmickey TAILQ_ENTRY(table_entry) list; 63df930be7Sderaadt }; 64e4de0f9aSmickey TAILQ_HEAD(, table_entry) table; 65ebad6d3cSmickey 66c72b5b24Smillert static void delete(TABLE_ENTRY *); 67df930be7Sderaadt 68df930be7Sderaadt /* 69e4de0f9aSmickey * Init the table 70e4de0f9aSmickey */ 71e4de0f9aSmickey void 726bcb9e83Sderaadt init_table(void) 73e4de0f9aSmickey { 74e4de0f9aSmickey TAILQ_INIT(&table); 75e4de0f9aSmickey } 76e4de0f9aSmickey 77e4de0f9aSmickey /* 78df930be7Sderaadt * Look in the table for an invitation that matches the current 79df930be7Sderaadt * request looking for an invitation 80df930be7Sderaadt */ 81df930be7Sderaadt CTL_MSG * 826bcb9e83Sderaadt find_match(CTL_MSG *request) 83df930be7Sderaadt { 84f58a73dfSotto TABLE_ENTRY *ptr, *next; 85df930be7Sderaadt time_t current_time; 86df930be7Sderaadt 87df930be7Sderaadt gettimeofday(&tp, &txp); 88df930be7Sderaadt current_time = tp.tv_sec; 89df930be7Sderaadt if (debug) 90df930be7Sderaadt print_request("find_match", request); 919723d6b1Sotto for (ptr = TAILQ_FIRST(&table); ptr != NULL; ptr = next) { 929723d6b1Sotto next = TAILQ_NEXT(ptr, list); 93e4de0f9aSmickey if ((current_time - ptr->time) > MAX_LIFE) { 94df930be7Sderaadt /* the entry is too old */ 95df930be7Sderaadt if (debug) 96df930be7Sderaadt print_request("deleting expired entry", 97df930be7Sderaadt &ptr->request); 98df930be7Sderaadt delete(ptr); 99df930be7Sderaadt continue; 100df930be7Sderaadt } 101df930be7Sderaadt if (debug) 102df930be7Sderaadt print_request("", &ptr->request); 103f58a73dfSotto if (ptr->request.type == LEAVE_INVITE && 104f58a73dfSotto strcmp(request->l_name, ptr->request.r_name) == 0 && 105f58a73dfSotto strcmp(request->r_name, ptr->request.l_name) == 0) 106df930be7Sderaadt return (&ptr->request); 107df930be7Sderaadt } 108ebad6d3cSmickey if (debug) 109ea0b9ac4Sderaadt syslog(LOG_DEBUG, "find_match: not found"); 110ebad6d3cSmickey 111df930be7Sderaadt return ((CTL_MSG *)0); 112df930be7Sderaadt } 113df930be7Sderaadt 114df930be7Sderaadt /* 115df930be7Sderaadt * Look for an identical request, as opposed to a complimentary 116df930be7Sderaadt * one as find_match does 117df930be7Sderaadt */ 118df930be7Sderaadt CTL_MSG * 1196bcb9e83Sderaadt find_request(CTL_MSG *request) 120df930be7Sderaadt { 121f58a73dfSotto TABLE_ENTRY *ptr, *next; 122df930be7Sderaadt time_t current_time; 123df930be7Sderaadt 124df930be7Sderaadt gettimeofday(&tp, &txp); 125df930be7Sderaadt current_time = tp.tv_sec; 126df930be7Sderaadt /* 127df930be7Sderaadt * See if this is a repeated message, and check for 128df930be7Sderaadt * out of date entries in the table while we are it. 129df930be7Sderaadt */ 130df930be7Sderaadt if (debug) 131df930be7Sderaadt print_request("find_request", request); 1329723d6b1Sotto for (ptr = TAILQ_FIRST(&table); ptr != NULL; ptr = next) { 1339723d6b1Sotto next = TAILQ_NEXT(ptr, list); 134e4de0f9aSmickey if ((current_time - ptr->time) > MAX_LIFE) { 135df930be7Sderaadt /* the entry is too old */ 136df930be7Sderaadt if (debug) 137df930be7Sderaadt print_request("deleting expired entry", 138df930be7Sderaadt &ptr->request); 139df930be7Sderaadt delete(ptr); 140df930be7Sderaadt continue; 141df930be7Sderaadt } 142df930be7Sderaadt if (debug) 143df930be7Sderaadt print_request("", &ptr->request); 144f58a73dfSotto if (request->pid == ptr->request.pid && 145df930be7Sderaadt request->type == ptr->request.type && 146f58a73dfSotto strcmp(request->r_name, ptr->request.r_name) == 0 && 147f58a73dfSotto strcmp(request->l_name, ptr->request.l_name) == 0) { 148df930be7Sderaadt /* update the time if we 'touch' it */ 149df930be7Sderaadt ptr->time = current_time; 150df930be7Sderaadt return (&ptr->request); 151df930be7Sderaadt } 152df930be7Sderaadt } 153df930be7Sderaadt return ((CTL_MSG *)0); 154df930be7Sderaadt } 155df930be7Sderaadt 156ebad6d3cSmickey void 1576bcb9e83Sderaadt insert_table(CTL_MSG *request, CTL_RESPONSE *response) 158df930be7Sderaadt { 15950d2b651Smpech TABLE_ENTRY *ptr; 160df930be7Sderaadt time_t current_time; 161df930be7Sderaadt 162ebad6d3cSmickey if (debug) 163ebad6d3cSmickey print_request( "insert_table", request ); 164df930be7Sderaadt gettimeofday(&tp, &txp); 165df930be7Sderaadt current_time = tp.tv_sec; 166df930be7Sderaadt request->id_num = new_id(); 167df930be7Sderaadt response->id_num = htonl(request->id_num); 168df930be7Sderaadt /* insert a new entry into the top of the list */ 169*205f2136Sderaadt ptr = malloc(sizeof(TABLE_ENTRY)); 170e4de0f9aSmickey if (ptr == NULL) { 171df930be7Sderaadt syslog(LOG_ERR, "insert_table: Out of memory"); 172df930be7Sderaadt _exit(1); 173df930be7Sderaadt } 174df930be7Sderaadt ptr->time = current_time; 175df930be7Sderaadt ptr->request = *request; 176e4de0f9aSmickey TAILQ_INSERT_HEAD(&table, ptr, list); 177df930be7Sderaadt } 178df930be7Sderaadt 179df930be7Sderaadt /* 180df930be7Sderaadt * Generate a unique non-zero sequence number 181df930be7Sderaadt */ 182ebad6d3cSmickey int 183ebad6d3cSmickey new_id(void) 184df930be7Sderaadt { 185df930be7Sderaadt static int current_id = 0; 186df930be7Sderaadt 187df930be7Sderaadt current_id = (current_id + 1) % MAX_ID; 188df930be7Sderaadt /* 0 is reserved, helps to pick up bugs */ 189df930be7Sderaadt if (current_id == 0) 190df930be7Sderaadt current_id = 1; 191df930be7Sderaadt return (current_id); 192df930be7Sderaadt } 193df930be7Sderaadt 194df930be7Sderaadt /* 195df930be7Sderaadt * Delete the invitation with id 'id_num' 196df930be7Sderaadt */ 197ebad6d3cSmickey int 1986bcb9e83Sderaadt delete_invite(int id_num) 199df930be7Sderaadt { 20050d2b651Smpech TABLE_ENTRY *ptr; 201df930be7Sderaadt 202df930be7Sderaadt if (debug) 203df930be7Sderaadt syslog(LOG_DEBUG, "delete_invite(%d)", id_num); 2049723d6b1Sotto TAILQ_FOREACH(ptr, &table, list) { 205df930be7Sderaadt if (ptr->request.id_num == id_num) 206df930be7Sderaadt break; 207df930be7Sderaadt if (debug) 208df930be7Sderaadt print_request("", &ptr->request); 209df930be7Sderaadt } 210e4de0f9aSmickey if (ptr != NULL) { 211df930be7Sderaadt delete(ptr); 212df930be7Sderaadt return (SUCCESS); 213df930be7Sderaadt } 214df930be7Sderaadt return (NOT_HERE); 215df930be7Sderaadt } 216df930be7Sderaadt 217df930be7Sderaadt /* 218df930be7Sderaadt * Classic delete from a double-linked list 219df930be7Sderaadt */ 220ebad6d3cSmickey static void 2216bcb9e83Sderaadt delete(TABLE_ENTRY *ptr) 222df930be7Sderaadt { 223df930be7Sderaadt 224df930be7Sderaadt if (debug) 225df930be7Sderaadt print_request("delete", &ptr->request); 226e4de0f9aSmickey TAILQ_REMOVE(&table, ptr, list); 227df930be7Sderaadt free((char *)ptr); 228df930be7Sderaadt } 229