1 /* $OpenBSD: roaming_common.c,v 1.5 2009/06/27 09:32:43 andreas Exp $ */
2 /*
3  * Copyright © 2013
4  *	Thorsten “mirabilos” Glaser <tg@mirbsd.org>
5  * Copyright (c) 2004-2009 AppGate Network Security AB
6  *
7  * Permission to use, copy, modify, and distribute this software for any
8  * purpose with or without fee is hereby granted, provided that the above
9  * copyright notice and this permission notice appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18  */
19 
20 #include <sys/types.h>
21 #include <sys/socket.h>
22 #include <sys/uio.h>
23 
24 #include <errno.h>
25 #include <inttypes.h>
26 #include <stdarg.h>
27 #include <string.h>
28 #include <unistd.h>
29 
30 #include "atomicio.h"
31 #include "log.h"
32 #include "packet.h"
33 #include "xmalloc.h"
34 #include "cipher.h"
35 #include "buffer.h"
36 #include "roaming.h"
37 
38 __RCSID("$MirOS: src/usr.bin/ssh/roaming_common.c,v 1.3 2013/10/31 20:07:12 tg Exp $");
39 
40 static size_t out_buf_size = 0;
41 static char *out_buf = NULL;
42 static size_t out_start;
43 static size_t out_last;
44 
45 static u_int64_t write_bytes = 0;
46 static u_int64_t read_bytes = 0;
47 
48 int roaming_enabled = 0;
49 int resume_in_progress = 0;
50 
51 int
get_snd_buf_size(void)52 get_snd_buf_size(void)
53 {
54 	int fd = packet_get_connection_out();
55 	int optval, optvallen;
56 
57 	optvallen = sizeof(optval);
58 	if (getsockopt(fd, SOL_SOCKET, SO_SNDBUF, &optval, &optvallen) != 0)
59 		optval = DEFAULT_ROAMBUF;
60 	return optval;
61 }
62 
63 int
get_recv_buf_size(void)64 get_recv_buf_size(void)
65 {
66 	int fd = packet_get_connection_in();
67 	int optval, optvallen;
68 
69 	optvallen = sizeof(optval);
70 	if (getsockopt(fd, SOL_SOCKET, SO_RCVBUF, &optval, &optvallen) != 0)
71 		optval = DEFAULT_ROAMBUF;
72 	return optval;
73 }
74 
75 void
set_out_buffer_size(size_t size)76 set_out_buffer_size(size_t size)
77 {
78 	/*
79 	 * The buffer size can only be set once and the buffer will live
80 	 * as long as the session lives.
81 	 */
82 	if (out_buf == NULL) {
83 		out_buf_size = size;
84 		out_buf = xmalloc(size);
85 		out_start = 0;
86 		out_last = 0;
87 	}
88 }
89 
90 u_int64_t
get_recv_bytes(void)91 get_recv_bytes(void)
92 {
93 	return read_bytes;
94 }
95 
96 void
add_recv_bytes(u_int64_t num)97 add_recv_bytes(u_int64_t num)
98 {
99 	read_bytes += num;
100 }
101 
102 u_int64_t
get_sent_bytes(void)103 get_sent_bytes(void)
104 {
105 	return write_bytes;
106 }
107 
108 void
roam_set_bytes(u_int64_t sent,u_int64_t recvd)109 roam_set_bytes(u_int64_t sent, u_int64_t recvd)
110 {
111 	read_bytes = recvd;
112 	write_bytes = sent;
113 }
114 
115 static void
buf_append(const char * buf,size_t count)116 buf_append(const char *buf, size_t count)
117 {
118 	if (count > out_buf_size) {
119 		buf += count - out_buf_size;
120 		count = out_buf_size;
121 	}
122 	if (count < out_buf_size - out_last) {
123 		memcpy(out_buf + out_last, buf, count);
124 		if (out_start > out_last)
125 			out_start += count;
126 		out_last += count;
127 	} else {
128 		/* data will wrap */
129 		size_t chunk = out_buf_size - out_last;
130 		memcpy(out_buf + out_last, buf, chunk);
131 		memcpy(out_buf, buf + chunk, count - chunk);
132 		out_last = count - chunk;
133 		out_start = out_last + 1;
134 	}
135 }
136 
137 ssize_t
roaming_write(int fd,const void * buf,size_t count,int * cont)138 roaming_write(int fd, const void *buf, size_t count,
139     int *cont __attribute__((__unused__)))
140 {
141 	ssize_t ret;
142 
143 	ret = write(fd, buf, count);
144 	if (ret > 0 && !resume_in_progress) {
145 		write_bytes += ret;
146 		if (out_buf_size > 0)
147 			buf_append(buf, ret);
148 	}
149 	debug3("Wrote %ld bytes for a total of %llu", (long)ret,
150 	    (unsigned long long)write_bytes);
151 	return ret;
152 }
153 
154 ssize_t
roaming_read(int fd,void * buf,size_t count,int * cont)155 roaming_read(int fd, void *buf, size_t count,
156     int *cont __attribute__((__unused__)))
157 {
158 	ssize_t ret = read(fd, buf, count);
159 	if (ret > 0) {
160 		if (!resume_in_progress) {
161 			read_bytes += ret;
162 		}
163 	}
164 	return ret;
165 }
166 
167 size_t
roaming_atomicio(ssize_t (* f)(int,void *,size_t),int fd,void * buf,size_t count)168 roaming_atomicio(ssize_t(*f)(int, void*, size_t), int fd, void *buf,
169     size_t count)
170 {
171 	size_t ret = atomicio(f, fd, buf, count);
172 
173 	if (f == vwrite && ret > 0 && !resume_in_progress) {
174 		write_bytes += ret;
175 	} else if (f == read && ret > 0 && !resume_in_progress) {
176 		read_bytes += ret;
177 	}
178 	return ret;
179 }
180 
181 void
resend_bytes(int fd,u_int64_t * offset)182 resend_bytes(int fd, u_int64_t *offset)
183 {
184 	size_t available, needed;
185 
186 	if (out_start < out_last)
187 		available = out_last - out_start;
188 	else
189 		available = out_buf_size;
190 	needed = write_bytes - *offset;
191 	debug3("resend_bytes: resend %lu bytes from %llu",
192 	    (unsigned long)needed, (unsigned long long)*offset);
193 	if (needed > available)
194 		fatal("Needed to resend more data than in the cache");
195 	if (out_last < needed) {
196 		int chunkend = needed - out_last;
197 		atomicio(vwrite, fd, out_buf + out_buf_size - chunkend,
198 		    chunkend);
199 		atomicio(vwrite, fd, out_buf, out_last);
200 	} else {
201 		atomicio(vwrite, fd, out_buf + (out_last - needed), needed);
202 	}
203 }
204