roaming_common.c

   1 /* $OpenBSD: roaming_common.c,v 1.6 2009/10/24 11:22:37 andreas 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
  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
  52 get_snd_buf_size()
  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
  64 get_recv_buf_size()
  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
  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
  91 get_recv_bytes(void)
  92 {
  93         return read_bytes;
  94 }
  95
  96 void
  97 add_recv_bytes(u_int64_t num)
  98 {
  99         read_bytes += num;
 100 }
 101
 102 u_int64_t
 103 get_sent_bytes(void)
 104 {
 105         return write_bytes;
 106 }
 107
 108 void
 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
 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
 138 roaming_write(int fd, const void *buf, size_t count, int *cont)
 139 {
 140         ssize_t ret;
 141
 142         ret = write(fd, buf, count);
 143         if (ret > 0 && !resume_in_progress) {
 144                 write_bytes += ret;
 145                 if (out_buf_size > 0)
 146                         buf_append(buf, ret);
 147         }
 148         debug3("Wrote %ld bytes for a total of %llu", (long)ret,
 149             (unsigned long long)write_bytes);
 150         if (out_buf_size > 0 &&
 151             (ret == 0 || (ret == -1 && errno == EPIPE))) {
 152                 if (wait_for_roaming_reconnect() != 0) {
 153                         ret = 0;
 154                         *cont = 1;
 155                 } else {
 156                         ret = -1;
 157                         errno = EAGAIN;
 158                 }
 159         }
 160         return ret;
 161 }
 162
 163 ssize_t
 164 roaming_read(int fd, void *buf, size_t count, int *cont)
 165 {
 166         ssize_t ret = read(fd, buf, count);
 167         if (ret > 0) {
 168                 if (!resume_in_progress) {
 169                         read_bytes += ret;
 170                 }
 171         } else if (out_buf_size > 0 &&
 172             (ret == 0 || (ret == -1 && (errno == ECONNRESET
 173             || errno == ECONNABORTED || errno == ETIMEDOUT
 174             || errno == EHOSTUNREACH)))) {
 175                 debug("roaming_read failed for %d  ret=%ld  errno=%d",
 176                     fd, (long)ret, errno);
 177                 ret = 0;
 178                 if (wait_for_roaming_reconnect() == 0)
 179                         *cont = 1;
 180         }
 181         return ret;
 182 }
 183
 184 size_t
 185 roaming_atomicio(ssize_t(*f)(int, void*, size_t), int fd, void *buf,
 186     size_t count)
 187 {
 188         size_t ret = atomicio(f, fd, buf, count);
 189
 190         if (f == vwrite && ret > 0 && !resume_in_progress) {
 191                 write_bytes += ret;
 192         } else if (f == read && ret > 0 && !resume_in_progress) {
 193                 read_bytes += ret;
 194         }
 195         return ret;
 196 }
 197
 198 void
 199 resend_bytes(int fd, u_int64_t *offset)
 200 {
 201         size_t available, needed;
 202
 203         if (out_start < out_last)
 204                 available = out_last - out_start;
 205         else
 206                 available = out_buf_size;
 207         needed = write_bytes - *offset;
 208         debug3("resend_bytes: resend %lu bytes from %llu",
 209             (unsigned long)needed, (unsigned long long)*offset);
 210         if (needed > available)
 211                 fatal("Needed to resend more data than in the cache");
 212         if (out_last < needed) {
 213                 int chunkend = needed - out_last;
 214                 atomicio(vwrite, fd, out_buf + out_buf_size - chunkend,
 215                     chunkend);
 216                 atomicio(vwrite, fd, out_buf, out_last);
 217         } else {
 218                 atomicio(vwrite, fd, out_buf + (out_last - needed), needed);
 219         }
 220 }
 221
 222 /*
 223  * Caclulate a new key after a reconnect
 224  */
 225 void
 226 calculate_new_key(u_int64_t *key, u_int64_t cookie, u_int64_t challenge)
 227 {
 228         const EVP_MD *md = EVP_sha1();
 229         EVP_MD_CTX ctx;
 230         char hash[EVP_MAX_MD_SIZE];
 231         Buffer b;
 232
 233         buffer_init(&b);
 234         buffer_put_int64(&b, *key);
 235         buffer_put_int64(&b, cookie);
 236         buffer_put_int64(&b, challenge);
 237
 238         EVP_DigestInit(&ctx, md);
 239         EVP_DigestUpdate(&ctx, buffer_ptr(&b), buffer_len(&b));
 240         EVP_DigestFinal(&ctx, hash, NULL);
 241
 242         buffer_clear(&b);
 243         buffer_append(&b, hash, EVP_MD_size(md));
 244         *key = buffer_get_int64(&b);
 245         buffer_free(&b);
 246 }