crypto/dist/heimdal/appl/rsh/common.c

   1 /*
   2  * Copyright (c) 1997-2004 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. Neither the name of the Institute nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #include "rsh_locl.h"
  35 __RCSID("$Heimdal: common.c 17450 2006-05-05 11:11:43Z lha $"
  36         "$NetBSD$");
  37
  38 #if defined(KRB4) || defined(KRB5)
  39
  40 #ifdef KRB5
  41 int key_usage = 1026;
  42
  43 void *ivec_in[2];
  44 void *ivec_out[2];
  45
  46 void
  47 init_ivecs(int client, int have_errsock)
  48 {
  49     size_t blocksize;
  50
  51     krb5_crypto_getblocksize(context, crypto, &blocksize);
  52
  53     ivec_in[0] = malloc(blocksize);
  54     memset(ivec_in[0], client, blocksize);
  55
  56     if(have_errsock) {
  57         ivec_in[1] = malloc(blocksize);
  58         memset(ivec_in[1], 2 | client, blocksize);
  59     } else
  60         ivec_in[1] = ivec_in[0];
  61
  62     ivec_out[0] = malloc(blocksize);
  63     memset(ivec_out[0], !client, blocksize);
  64
  65     if(have_errsock) {
  66         ivec_out[1] = malloc(blocksize);
  67         memset(ivec_out[1], 2 | !client, blocksize);
  68     } else
  69         ivec_out[1] = ivec_out[0];
  70 }
  71 #endif
  72
  73
  74 ssize_t
  75 do_read (int fd, void *buf, size_t sz, void *ivec)
  76 {
  77     if (do_encrypt) {
  78 #ifdef KRB4
  79         if (auth_method == AUTH_KRB4) {
  80             return des_enc_read (fd, buf, sz, schedule, &iv);
  81         } else
  82 #endif /* KRB4 */
  83 #ifdef KRB5
  84         if(auth_method == AUTH_KRB5) {
  85             krb5_error_code ret;
  86             uint32_t len, outer_len;
  87             int status;
  88             krb5_data data;
  89             void *edata;
  90
  91             ret = krb5_net_read (context, &fd, &len, 4);
  92             if (ret <= 0)
  93                 return ret;
  94             len = ntohl(len);
  95             if (len > sz)
  96                 abort ();
  97             /* ivec will be non null for protocol version 2 */
  98             if(ivec != NULL)
  99                 outer_len = krb5_get_wrapped_length (context, crypto, len + 4);
 100             else
 101                 outer_len = krb5_get_wrapped_length (context, crypto, len);
 102             edata = malloc (outer_len);
 103             if (edata == NULL)
 104                 errx (1, "malloc: cannot allocate %u bytes", outer_len);
 105             ret = krb5_net_read (context, &fd, edata, outer_len);
 106             if (ret <= 0)
 107                 return ret;
 108
 109             status = krb5_decrypt_ivec(context, crypto, key_usage,
 110                                        edata, outer_len, &data, ivec);
 111             free (edata);
 112
 113             if (status)
 114                 krb5_err (context, 1, status, "decrypting data");
 115             if(ivec != NULL) {
 116                 unsigned long l;
 117                 if(data.length < len + 4)
 118                     errx (1, "data received is too short");
 119                 _krb5_get_int(data.data, &l, 4);
 120                 if(l != len)
 121                     errx (1, "inconsistency in received data");
 122                 memcpy (buf, (unsigned char *)data.data+4, len);
 123             } else
 124                 memcpy (buf, data.data, len);
 125             krb5_data_free (&data);
 126             return len;
 127         } else
 128 #endif /* KRB5 */
 129             abort ();
 130     } else
 131         return read (fd, buf, sz);
 132 }
 133
 134 ssize_t
 135 do_write (int fd, void *buf, size_t sz, void *ivec)
 136 {
 137     if (do_encrypt) {
 138 #ifdef KRB4
 139         if(auth_method == AUTH_KRB4) {
 140             return des_enc_write (fd, buf, sz, schedule, &iv);
 141         } else
 142 #endif /* KRB4 */
 143 #ifdef KRB5
 144         if(auth_method == AUTH_KRB5) {
 145             krb5_error_code status;
 146             krb5_data data;
 147             unsigned char len[4];
 148             int ret;
 149
 150             _krb5_put_int(len, sz, 4);
 151             if(ivec != NULL) {
 152                 unsigned char *tmp = malloc(sz + 4);
 153                 if(tmp == NULL)
 154                     err(1, "malloc");
 155                 _krb5_put_int(tmp, sz, 4);
 156                 memcpy(tmp + 4, buf, sz);
 157                 status = krb5_encrypt_ivec(context, crypto, key_usage,
 158                                            tmp, sz + 4, &data, ivec);
 159                 free(tmp);
 160             } else
 161                 status = krb5_encrypt_ivec(context, crypto, key_usage,
 162                                            buf, sz, &data, ivec);
 163
 164             if (status)
 165                 krb5_err(context, 1, status, "encrypting data");
 166
 167             ret = krb5_net_write (context, &fd, len, 4);
 168             if (ret != 4)
 169                 return ret;
 170             ret = krb5_net_write (context, &fd, data.data, data.length);
 171             if (ret != data.length)
 172                 return ret;
 173             free (data.data);
 174             return sz;
 175         } else
 176 #endif /* KRB5 */
 177             abort();
 178     } else
 179         return write (fd, buf, sz);
 180 }
 181 #endif /* KRB4 || KRB5 */