1 /* $OpenBSD: roaming_common.c,v 1.12 2014/01/09 23:20:00 djm Exp $ */
2 /*
3 * Copyright (c) 2004-2009 AppGate Network Security AB
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 */
17
18 #include "includes.h"
19
20 #include <sys/types.h>
21 #include <sys/socket.h>
22 #include <sys/uio.h>
23
24 #include <errno.h>
25 #ifdef HAVE_INTTYPES_H
26 #include <inttypes.h>
27 #endif
28 #include <stdarg.h>
29 #include <string.h>
30 #include <unistd.h>
31
32 #include "atomicio.h"
33 #include "log.h"
34 #include "packet.h"
35 #include "xmalloc.h"
36 #include "cipher.h"
37 #include "buffer.h"
38 #include "roaming.h"
39 #include "digest.h"
40
41 static size_t out_buf_size = 0;
42 static char *out_buf = NULL;
43 static size_t out_start;
44 static size_t out_last;
45
46 static u_int64_t write_bytes = 0;
47 static u_int64_t read_bytes = 0;
48
49 int roaming_enabled = 0;
50 int resume_in_progress = 0;
51
52 int
get_snd_buf_size(void)53 get_snd_buf_size(void)
54 {
55 int fd = packet_get_connection_out();
56 int optval;
57 socklen_t optvallen = sizeof(optval);
58
59 if (getsockopt(fd, SOL_SOCKET, SO_SNDBUF, &optval, &optvallen) != 0)
60 optval = DEFAULT_ROAMBUF;
61 return optval;
62 }
63
64 int
get_recv_buf_size(void)65 get_recv_buf_size(void)
66 {
67 int fd = packet_get_connection_in();
68 int optval;
69 socklen_t optvallen = sizeof(optval);
70
71 if (getsockopt(fd, SOL_SOCKET, SO_RCVBUF, &optval, &optvallen) != 0)
72 optval = DEFAULT_ROAMBUF;
73 return optval;
74 }
75
76 void
set_out_buffer_size(size_t size)77 set_out_buffer_size(size_t size)
78 {
79 if (size == 0 || size > MAX_ROAMBUF)
80 fatal("%s: bad buffer size %lu", __func__, (u_long)size);
81 /*
82 * The buffer size can only be set once and the buffer will live
83 * as long as the session lives.
84 */
85 if (out_buf == NULL) {
86 out_buf_size = size;
87 out_buf = xmalloc(size);
88 out_start = 0;
89 out_last = 0;
90 }
91 }
92
93 u_int64_t
get_recv_bytes(void)94 get_recv_bytes(void)
95 {
96 return read_bytes;
97 }
98
99 void
add_recv_bytes(u_int64_t num)100 add_recv_bytes(u_int64_t num)
101 {
102 read_bytes += num;
103 }
104
105 u_int64_t
get_sent_bytes(void)106 get_sent_bytes(void)
107 {
108 return write_bytes;
109 }
110
111 void
roam_set_bytes(u_int64_t sent,u_int64_t recvd)112 roam_set_bytes(u_int64_t sent, u_int64_t recvd)
113 {
114 read_bytes = recvd;
115 write_bytes = sent;
116 }
117
118 static void
buf_append(const char * buf,size_t count)119 buf_append(const char *buf, size_t count)
120 {
121 if (count > out_buf_size) {
122 buf += count - out_buf_size;
123 count = out_buf_size;
124 }
125 if (count < out_buf_size - out_last) {
126 memcpy(out_buf + out_last, buf, count);
127 if (out_start > out_last)
128 out_start += count;
129 out_last += count;
130 } else {
131 /* data will wrap */
132 size_t chunk = out_buf_size - out_last;
133 memcpy(out_buf + out_last, buf, chunk);
134 memcpy(out_buf, buf + chunk, count - chunk);
135 out_last = count - chunk;
136 out_start = out_last + 1;
137 }
138 }
139
140 ssize_t
roaming_write(int fd,const void * buf,size_t count,int * cont)141 roaming_write(int fd, const void *buf, size_t count, int *cont)
142 {
143 ssize_t ret;
144
145 ret = write(fd, buf, count);
146 if (ret > 0 && !resume_in_progress) {
147 write_bytes += ret;
148 if (out_buf_size > 0)
149 buf_append(buf, ret);
150 }
151 if (out_buf_size > 0 &&
152 (ret == 0 || (ret == -1 && errno == EPIPE))) {
153 if (wait_for_roaming_reconnect() != 0) {
154 ret = 0;
155 *cont = 1;
156 } else {
157 ret = -1;
158 errno = EAGAIN;
159 }
160 }
161 return ret;
162 }
163
164 ssize_t
roaming_read(int fd,void * buf,size_t count,int * cont)165 roaming_read(int fd, void *buf, size_t count, int *cont)
166 {
167 ssize_t ret = read(fd, buf, count);
168 if (ret > 0) {
169 if (!resume_in_progress) {
170 read_bytes += ret;
171 }
172 } else if (out_buf_size > 0 &&
173 (ret == 0 || (ret == -1 && (errno == ECONNRESET
174 || errno == ECONNABORTED || errno == ETIMEDOUT
175 || errno == EHOSTUNREACH)))) {
176 debug("roaming_read failed for %d ret=%ld errno=%d",
177 fd, (long)ret, errno);
178 ret = 0;
179 if (wait_for_roaming_reconnect() == 0)
180 *cont = 1;
181 }
182 return ret;
183 }
184
185 size_t
roaming_atomicio(ssize_t (* f)(int,void *,size_t),int fd,void * buf,size_t count)186 roaming_atomicio(ssize_t(*f)(int, void*, size_t), int fd, void *buf,
187 size_t count)
188 {
189 size_t ret = atomicio(f, fd, buf, count);
190
191 if (f == vwrite && ret > 0 && !resume_in_progress) {
192 write_bytes += ret;
193 } else if (f == read && ret > 0 && !resume_in_progress) {
194 read_bytes += ret;
195 }
196 return ret;
197 }
198
199 void
resend_bytes(int fd,u_int64_t * offset)200 resend_bytes(int fd, u_int64_t *offset)
201 {
202 size_t available, needed;
203
204 if (out_start < out_last)
205 available = out_last - out_start;
206 else
207 available = out_buf_size;
208 needed = write_bytes - *offset;
209 debug3("resend_bytes: resend %lu bytes from %llu",
210 (unsigned long)needed, (unsigned long long)*offset);
211 if (needed > available)
212 fatal("Needed to resend more data than in the cache");
213 if (out_last < needed) {
214 int chunkend = needed - out_last;
215 atomicio(vwrite, fd, out_buf + out_buf_size - chunkend,
216 chunkend);
217 atomicio(vwrite, fd, out_buf, out_last);
218 } else {
219 atomicio(vwrite, fd, out_buf + (out_last - needed), needed);
220 }
221 }
222
223 /*
224 * Caclulate a new key after a reconnect
225 */
226 void
calculate_new_key(u_int64_t * key,u_int64_t cookie,u_int64_t challenge)227 calculate_new_key(u_int64_t *key, u_int64_t cookie, u_int64_t challenge)
228 {
229 u_char hash[SSH_DIGEST_MAX_LENGTH];
230 Buffer b;
231
232 buffer_init(&b);
233 buffer_put_int64(&b, *key);
234 buffer_put_int64(&b, cookie);
235 buffer_put_int64(&b, challenge);
236
237 if (ssh_digest_buffer(SSH_DIGEST_SHA1, &b, hash, sizeof(hash)) != 0)
238 fatal("%s: digest_buffer failed", __func__);
239
240 buffer_clear(&b);
241 buffer_append(&b, hash, ssh_digest_bytes(SSH_DIGEST_SHA1));
242 *key = buffer_get_int64(&b);
243 buffer_free(&b);
244 }
245