1 /*
2 * Dropbear SSH
3 *
4 * Copyright (c) 2002,2003 Matt Johnston
5 * All rights reserved.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a copy
8 * of this software and associated documentation files (the "Software"), to deal
9 * in the Software without restriction, including without limitation the rights
10 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11 * copies of the Software, and to permit persons to whom the Software is
12 * furnished to do so, subject to the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be included in
15 * all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
20 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
23 * SOFTWARE. */
24
25 #include "includes.h"
26 #include "listener.h"
27 #include "session.h"
28 #include "dbutil.h"
29
listeners_initialise()30 void listeners_initialise() {
31
32 /* just one slot to start with */
33 ses.listeners = (struct Listener**)m_malloc(sizeof(struct Listener*));
34 ses.listensize = 1;
35 ses.listeners[0] = NULL;
36
37 }
38
set_listener_fds(fd_set * readfds)39 void set_listener_fds(fd_set * readfds) {
40
41 unsigned int i, j;
42 struct Listener *listener;
43
44 /* check each in turn */
45 for (i = 0; i < ses.listensize; i++) {
46 listener = ses.listeners[i];
47 if (listener != NULL) {
48 for (j = 0; j < listener->nsocks; j++) {
49 FD_SET(listener->socks[j], readfds);
50 }
51 }
52 }
53 }
54
55
handle_listeners(fd_set * readfds)56 void handle_listeners(fd_set * readfds) {
57
58 unsigned int i, j;
59 struct Listener *listener;
60 int sock;
61
62 /* check each in turn */
63 for (i = 0; i < ses.listensize; i++) {
64 listener = ses.listeners[i];
65 if (listener != NULL) {
66 for (j = 0; j < listener->nsocks; j++) {
67 sock = listener->socks[j];
68 if (FD_ISSET(sock, readfds)) {
69 listener->acceptor(listener, sock);
70 }
71 }
72 }
73 }
74 } /* Woo brace matching */
75
76
77 /* acceptor(int fd, void* typedata) is a function to accept connections,
78 * cleanup(void* typedata) happens when cleaning up */
new_listener(int socks[],unsigned int nsocks,int type,void * typedata,void (* acceptor)(struct Listener * listener,int sock),void (* cleanup)(struct Listener *))79 struct Listener* new_listener(int socks[], unsigned int nsocks,
80 int type, void* typedata,
81 void (*acceptor)(struct Listener* listener, int sock),
82 void (*cleanup)(struct Listener*)) {
83
84 unsigned int i, j;
85 struct Listener *newlisten = NULL;
86 /* try get a new structure to hold it */
87 for (i = 0; i < ses.listensize; i++) {
88 if (ses.listeners[i] == NULL) {
89 break;
90 }
91 }
92
93 /* or create a new one */
94 if (i == ses.listensize) {
95 if (ses.listensize > MAX_LISTENERS) {
96 TRACE(("leave newlistener: too many already"))
97 for (j = 0; j < nsocks; j++) {
98 close(socks[i]);
99 }
100 return NULL;
101 }
102
103 ses.listeners = (struct Listener**)m_realloc(ses.listeners,
104 (ses.listensize+LISTENER_EXTEND_SIZE)
105 *sizeof(struct Listener*));
106
107 ses.listensize += LISTENER_EXTEND_SIZE;
108
109 for (j = i; j < ses.listensize; j++) {
110 ses.listeners[j] = NULL;
111 }
112 }
113
114 for (j = 0; j < nsocks; j++) {
115 ses.maxfd = MAX(ses.maxfd, socks[j]);
116 }
117
118 TRACE(("new listener num %d ", i))
119
120 newlisten = (struct Listener*)m_malloc(sizeof(struct Listener));
121 newlisten->index = i;
122 newlisten->type = type;
123 newlisten->typedata = typedata;
124 newlisten->nsocks = nsocks;
125 memcpy(newlisten->socks, socks, nsocks * sizeof(int));
126 newlisten->acceptor = acceptor;
127 newlisten->cleanup = cleanup;
128
129 ses.listeners[i] = newlisten;
130 return newlisten;
131 }
132
133 /* Return the first listener which matches the type-specific comparison
134 * function. Particularly needed for global requests, like tcp */
get_listener(int type,void * typedata,int (* match)(void *,void *))135 struct Listener * get_listener(int type, void* typedata,
136 int (*match)(void*, void*)) {
137
138 unsigned int i;
139 struct Listener* listener;
140
141 for (i = 0, listener = ses.listeners[i]; i < ses.listensize; i++) {
142 if (listener->type == type
143 && match(typedata, listener->typedata)) {
144 return listener;
145 }
146 }
147
148 return NULL;
149 }
150
remove_listener(struct Listener * listener)151 void remove_listener(struct Listener* listener) {
152
153 unsigned int j;
154
155 if (listener->cleanup) {
156 listener->cleanup(listener);
157 }
158
159 for (j = 0; j < listener->nsocks; j++) {
160 close(listener->socks[j]);
161 }
162 ses.listeners[listener->index] = NULL;
163 m_free(listener);
164
165 }
166