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("$Id$"); 36 37 #if 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 KRB5 78 if(auth_method == AUTH_KRB5) { 79 krb5_error_code ret; 80 uint32_t len, outer_len; 81 int status; 82 krb5_data data; 83 void *edata; 84 85 ret = krb5_net_read (context, &fd, &len, 4); 86 if (ret <= 0) 87 return ret; 88 len = ntohl(len); 89 if (len > sz) 90 abort (); 91 /* ivec will be non null for protocol version 2 */ 92 if(ivec != NULL) 93 outer_len = krb5_get_wrapped_length (context, crypto, len + 4); 94 else 95 outer_len = krb5_get_wrapped_length (context, crypto, len); 96 edata = malloc (outer_len); 97 if (edata == NULL) 98 errx (1, "malloc: cannot allocate %u bytes", outer_len); 99 ret = krb5_net_read (context, &fd, edata, outer_len); 100 if (ret <= 0) { 101 free(edata); 102 return ret; 103 } 104 105 status = krb5_decrypt_ivec(context, crypto, key_usage, 106 edata, outer_len, &data, ivec); 107 free (edata); 108 109 if (status) 110 krb5_err (context, 1, status, "decrypting data"); 111 if(ivec != NULL) { 112 unsigned long l; 113 if(data.length < len + 4) 114 errx (1, "data received is too short"); 115 _krb5_get_int(data.data, &l, 4); 116 if(l != len) 117 errx (1, "inconsistency in received data"); 118 memcpy (buf, (unsigned char *)data.data+4, len); 119 } else 120 memcpy (buf, data.data, len); 121 krb5_data_free (&data); 122 return len; 123 } else 124 #endif /* KRB5 */ 125 abort (); 126 } else 127 return read (fd, buf, sz); 128 } 129 130 ssize_t 131 do_write (int fd, void *buf, size_t sz, void *ivec) 132 { 133 if (do_encrypt) { 134 #ifdef KRB5 135 if(auth_method == AUTH_KRB5) { 136 krb5_error_code status; 137 krb5_data data; 138 unsigned char len[4]; 139 int ret; 140 141 _krb5_put_int(len, sz, 4); 142 if(ivec != NULL) { 143 unsigned char *tmp = malloc(sz + 4); 144 if(tmp == NULL) 145 err(1, "malloc"); 146 _krb5_put_int(tmp, sz, 4); 147 memcpy(tmp + 4, buf, sz); 148 status = krb5_encrypt_ivec(context, crypto, key_usage, 149 tmp, sz + 4, &data, ivec); 150 free(tmp); 151 } else 152 status = krb5_encrypt_ivec(context, crypto, key_usage, 153 buf, sz, &data, ivec); 154 155 if (status) 156 krb5_err(context, 1, status, "encrypting data"); 157 158 ret = krb5_net_write (context, &fd, len, 4); 159 if (ret != 4) 160 return ret; 161 ret = krb5_net_write (context, &fd, data.data, data.length); 162 if (ret != data.length) 163 return ret; 164 free (data.data); 165 return sz; 166 } else 167 #endif /* KRB5 */ 168 abort(); 169 } else 170 return write (fd, buf, sz); 171 } 172 #endif /* KRB5 */ 173