1 /* 2 * Copyright (c) 1997-2004 Kungliga Tekniska H�gskolan 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("$Id: common.c 17450 2006-05-05 11:11:43Z lha $"); 36 37 #if defined(KRB4) || defined(KRB5) 38 39 #ifdef KRB5 40 int key_usage = 1026; 41 42 void *ivec_in[2]; 43 void *ivec_out[2]; 44 45 void 46 init_ivecs(int client, int have_errsock) 47 { 48 size_t blocksize; 49 50 krb5_crypto_getblocksize(context, crypto, &blocksize); 51 52 ivec_in[0] = malloc(blocksize); 53 memset(ivec_in[0], client, blocksize); 54 55 if(have_errsock) { 56 ivec_in[1] = malloc(blocksize); 57 memset(ivec_in[1], 2 | client, blocksize); 58 } else 59 ivec_in[1] = ivec_in[0]; 60 61 ivec_out[0] = malloc(blocksize); 62 memset(ivec_out[0], !client, blocksize); 63 64 if(have_errsock) { 65 ivec_out[1] = malloc(blocksize); 66 memset(ivec_out[1], 2 | !client, blocksize); 67 } else 68 ivec_out[1] = ivec_out[0]; 69 } 70 #endif 71 72 73 ssize_t 74 do_read (int fd, void *buf, size_t sz, void *ivec) 75 { 76 if (do_encrypt) { 77 #ifdef KRB4 78 if (auth_method == AUTH_KRB4) { 79 return des_enc_read (fd, buf, sz, schedule, &iv); 80 } else 81 #endif /* KRB4 */ 82 #ifdef KRB5 83 if(auth_method == AUTH_KRB5) { 84 krb5_error_code ret; 85 uint32_t len, outer_len; 86 int status; 87 krb5_data data; 88 void *edata; 89 90 ret = krb5_net_read (context, &fd, &len, 4); 91 if (ret <= 0) 92 return ret; 93 len = ntohl(len); 94 if (len > sz) 95 abort (); 96 /* ivec will be non null for protocol version 2 */ 97 if(ivec != NULL) 98 outer_len = krb5_get_wrapped_length (context, crypto, len + 4); 99 else 100 outer_len = krb5_get_wrapped_length (context, crypto, len); 101 edata = malloc (outer_len); 102 if (edata == NULL) 103 errx (1, "malloc: cannot allocate %u bytes", outer_len); 104 ret = krb5_net_read (context, &fd, edata, outer_len); 105 if (ret <= 0) 106 return ret; 107 108 status = krb5_decrypt_ivec(context, crypto, key_usage, 109 edata, outer_len, &data, ivec); 110 free (edata); 111 112 if (status) 113 krb5_err (context, 1, status, "decrypting data"); 114 if(ivec != NULL) { 115 unsigned long l; 116 if(data.length < len + 4) 117 errx (1, "data received is too short"); 118 _krb5_get_int(data.data, &l, 4); 119 if(l != len) 120 errx (1, "inconsistency in received data"); 121 memcpy (buf, (unsigned char *)data.data+4, len); 122 } else 123 memcpy (buf, data.data, len); 124 krb5_data_free (&data); 125 return len; 126 } else 127 #endif /* KRB5 */ 128 abort (); 129 } else 130 return read (fd, buf, sz); 131 } 132 133 ssize_t 134 do_write (int fd, void *buf, size_t sz, void *ivec) 135 { 136 if (do_encrypt) { 137 #ifdef KRB4 138 if(auth_method == AUTH_KRB4) { 139 return des_enc_write (fd, buf, sz, schedule, &iv); 140 } else 141 #endif /* KRB4 */ 142 #ifdef KRB5 143 if(auth_method == AUTH_KRB5) { 144 krb5_error_code status; 145 krb5_data data; 146 unsigned char len[4]; 147 int ret; 148 149 _krb5_put_int(len, sz, 4); 150 if(ivec != NULL) { 151 unsigned char *tmp = malloc(sz + 4); 152 if(tmp == NULL) 153 err(1, "malloc"); 154 _krb5_put_int(tmp, sz, 4); 155 memcpy(tmp + 4, buf, sz); 156 status = krb5_encrypt_ivec(context, crypto, key_usage, 157 tmp, sz + 4, &data, ivec); 158 free(tmp); 159 } else 160 status = krb5_encrypt_ivec(context, crypto, key_usage, 161 buf, sz, &data, ivec); 162 163 if (status) 164 krb5_err(context, 1, status, "encrypting data"); 165 166 ret = krb5_net_write (context, &fd, len, 4); 167 if (ret != 4) 168 return ret; 169 ret = krb5_net_write (context, &fd, data.data, data.length); 170 if (ret != data.length) 171 return ret; 172 free (data.data); 173 return sz; 174 } else 175 #endif /* KRB5 */ 176 abort(); 177 } else 178 return write (fd, buf, sz); 179 } 180 #endif /* KRB4 || KRB5 */ 181