1*1a3f6550Scheloha /* $OpenBSD: table.c,v 1.20 2019/08/09 22:52:13 cheloha 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 */
40e4de0f9aSmickey #include <sys/queue.h>
41f652621fSmestre #include <sys/socket.h>
42358ea70dSguenther #include <sys/time.h>
43df930be7Sderaadt #include <protocols/talkd.h>
44f652621fSmestre
45df930be7Sderaadt #include <stdlib.h>
46df930be7Sderaadt #include <string.h>
47f652621fSmestre #include <syslog.h>
48f652621fSmestre #include <unistd.h>
49f652621fSmestre
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
56df930be7Sderaadt typedef struct table_entry TABLE_ENTRY;
57df930be7Sderaadt
58df930be7Sderaadt struct table_entry {
59df930be7Sderaadt CTL_MSG request;
60e4de0f9aSmickey time_t time;
61e4de0f9aSmickey TAILQ_ENTRY(table_entry) list;
62df930be7Sderaadt };
63e4de0f9aSmickey TAILQ_HEAD(, table_entry) table;
64ebad6d3cSmickey
65c72b5b24Smillert static void delete(TABLE_ENTRY *);
66df930be7Sderaadt
67df930be7Sderaadt /*
68e4de0f9aSmickey * Init the table
69e4de0f9aSmickey */
70e4de0f9aSmickey void
init_table(void)716bcb9e83Sderaadt init_table(void)
72e4de0f9aSmickey {
73e4de0f9aSmickey TAILQ_INIT(&table);
74e4de0f9aSmickey }
75e4de0f9aSmickey
76e4de0f9aSmickey /*
77df930be7Sderaadt * Look in the table for an invitation that matches the current
78df930be7Sderaadt * request looking for an invitation
79df930be7Sderaadt */
80df930be7Sderaadt CTL_MSG *
find_match(CTL_MSG * request)816bcb9e83Sderaadt find_match(CTL_MSG *request)
82df930be7Sderaadt {
83f58a73dfSotto TABLE_ENTRY *ptr, *next;
84df930be7Sderaadt time_t current_time;
85df930be7Sderaadt
86*1a3f6550Scheloha gettimeofday(&tp, NULL);
87df930be7Sderaadt current_time = tp.tv_sec;
88df930be7Sderaadt if (debug)
89df930be7Sderaadt print_request("find_match", request);
909723d6b1Sotto for (ptr = TAILQ_FIRST(&table); ptr != NULL; ptr = next) {
919723d6b1Sotto next = TAILQ_NEXT(ptr, list);
92e4de0f9aSmickey if ((current_time - ptr->time) > MAX_LIFE) {
93df930be7Sderaadt /* the entry is too old */
94df930be7Sderaadt if (debug)
95df930be7Sderaadt print_request("deleting expired entry",
96df930be7Sderaadt &ptr->request);
97df930be7Sderaadt delete(ptr);
98df930be7Sderaadt continue;
99df930be7Sderaadt }
100df930be7Sderaadt if (debug)
101df930be7Sderaadt print_request("", &ptr->request);
102f58a73dfSotto if (ptr->request.type == LEAVE_INVITE &&
103f58a73dfSotto strcmp(request->l_name, ptr->request.r_name) == 0 &&
104f58a73dfSotto strcmp(request->r_name, ptr->request.l_name) == 0)
105df930be7Sderaadt return (&ptr->request);
106df930be7Sderaadt }
107ebad6d3cSmickey if (debug)
108ea0b9ac4Sderaadt syslog(LOG_DEBUG, "find_match: not found");
109ebad6d3cSmickey
110c9899b11Skrw return (NULL);
111df930be7Sderaadt }
112df930be7Sderaadt
113df930be7Sderaadt /*
114df930be7Sderaadt * Look for an identical request, as opposed to a complimentary
115df930be7Sderaadt * one as find_match does
116df930be7Sderaadt */
117df930be7Sderaadt CTL_MSG *
find_request(CTL_MSG * request)1186bcb9e83Sderaadt find_request(CTL_MSG *request)
119df930be7Sderaadt {
120f58a73dfSotto TABLE_ENTRY *ptr, *next;
121df930be7Sderaadt time_t current_time;
122df930be7Sderaadt
123*1a3f6550Scheloha gettimeofday(&tp, NULL);
124df930be7Sderaadt current_time = tp.tv_sec;
125df930be7Sderaadt /*
126df930be7Sderaadt * See if this is a repeated message, and check for
127df930be7Sderaadt * out of date entries in the table while we are it.
128df930be7Sderaadt */
129df930be7Sderaadt if (debug)
130df930be7Sderaadt print_request("find_request", request);
1319723d6b1Sotto for (ptr = TAILQ_FIRST(&table); ptr != NULL; ptr = next) {
1329723d6b1Sotto next = TAILQ_NEXT(ptr, list);
133e4de0f9aSmickey if ((current_time - ptr->time) > MAX_LIFE) {
134df930be7Sderaadt /* the entry is too old */
135df930be7Sderaadt if (debug)
136df930be7Sderaadt print_request("deleting expired entry",
137df930be7Sderaadt &ptr->request);
138df930be7Sderaadt delete(ptr);
139df930be7Sderaadt continue;
140df930be7Sderaadt }
141df930be7Sderaadt if (debug)
142df930be7Sderaadt print_request("", &ptr->request);
143f58a73dfSotto if (request->pid == ptr->request.pid &&
144df930be7Sderaadt request->type == ptr->request.type &&
145f58a73dfSotto strcmp(request->r_name, ptr->request.r_name) == 0 &&
146f58a73dfSotto strcmp(request->l_name, ptr->request.l_name) == 0) {
147df930be7Sderaadt /* update the time if we 'touch' it */
148df930be7Sderaadt ptr->time = current_time;
149df930be7Sderaadt return (&ptr->request);
150df930be7Sderaadt }
151df930be7Sderaadt }
152c9899b11Skrw return (NULL);
153df930be7Sderaadt }
154df930be7Sderaadt
155ebad6d3cSmickey void
insert_table(CTL_MSG * request,CTL_RESPONSE * response)1566bcb9e83Sderaadt insert_table(CTL_MSG *request, CTL_RESPONSE *response)
157df930be7Sderaadt {
15850d2b651Smpech TABLE_ENTRY *ptr;
159df930be7Sderaadt time_t current_time;
160df930be7Sderaadt
161ebad6d3cSmickey if (debug)
162ebad6d3cSmickey print_request( "insert_table", request );
163*1a3f6550Scheloha gettimeofday(&tp, NULL);
164df930be7Sderaadt current_time = tp.tv_sec;
165df930be7Sderaadt request->id_num = new_id();
166df930be7Sderaadt response->id_num = htonl(request->id_num);
167df930be7Sderaadt /* insert a new entry into the top of the list */
168205f2136Sderaadt ptr = malloc(sizeof(TABLE_ENTRY));
169e4de0f9aSmickey if (ptr == NULL) {
170df930be7Sderaadt syslog(LOG_ERR, "insert_table: Out of memory");
171df930be7Sderaadt _exit(1);
172df930be7Sderaadt }
173df930be7Sderaadt ptr->time = current_time;
174df930be7Sderaadt ptr->request = *request;
175e4de0f9aSmickey TAILQ_INSERT_HEAD(&table, ptr, list);
176df930be7Sderaadt }
177df930be7Sderaadt
178df930be7Sderaadt /*
179df930be7Sderaadt * Generate a unique non-zero sequence number
180df930be7Sderaadt */
181ebad6d3cSmickey int
new_id(void)182ebad6d3cSmickey new_id(void)
183df930be7Sderaadt {
184df930be7Sderaadt static int current_id = 0;
185df930be7Sderaadt
186df930be7Sderaadt current_id = (current_id + 1) % MAX_ID;
187df930be7Sderaadt /* 0 is reserved, helps to pick up bugs */
188df930be7Sderaadt if (current_id == 0)
189df930be7Sderaadt current_id = 1;
190df930be7Sderaadt return (current_id);
191df930be7Sderaadt }
192df930be7Sderaadt
193df930be7Sderaadt /*
194df930be7Sderaadt * Delete the invitation with id 'id_num'
195df930be7Sderaadt */
196ebad6d3cSmickey int
delete_invite(int id_num)1976bcb9e83Sderaadt delete_invite(int id_num)
198df930be7Sderaadt {
19950d2b651Smpech TABLE_ENTRY *ptr;
200df930be7Sderaadt
201df930be7Sderaadt if (debug)
202df930be7Sderaadt syslog(LOG_DEBUG, "delete_invite(%d)", id_num);
2039723d6b1Sotto TAILQ_FOREACH(ptr, &table, list) {
204df930be7Sderaadt if (ptr->request.id_num == id_num)
205df930be7Sderaadt break;
206df930be7Sderaadt if (debug)
207df930be7Sderaadt print_request("", &ptr->request);
208df930be7Sderaadt }
209e4de0f9aSmickey if (ptr != NULL) {
210df930be7Sderaadt delete(ptr);
211df930be7Sderaadt return (SUCCESS);
212df930be7Sderaadt }
213df930be7Sderaadt return (NOT_HERE);
214df930be7Sderaadt }
215df930be7Sderaadt
216df930be7Sderaadt /*
217df930be7Sderaadt * Classic delete from a double-linked list
218df930be7Sderaadt */
219ebad6d3cSmickey static void
delete(TABLE_ENTRY * ptr)2206bcb9e83Sderaadt delete(TABLE_ENTRY *ptr)
221df930be7Sderaadt {
222df930be7Sderaadt
223df930be7Sderaadt if (debug)
224df930be7Sderaadt print_request("delete", &ptr->request);
225e4de0f9aSmickey TAILQ_REMOVE(&table, ptr, list);
226df930be7Sderaadt free((char *)ptr);
227df930be7Sderaadt }
228