1 /* 2 * Copyright (c) 1997 - 2001 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 <krb5_locl.h> 35 36 RCSID("$Id: rd_priv.c,v 1.28 2001/05/14 06:14:50 assar Exp $"); 37 38 krb5_error_code 39 krb5_rd_priv(krb5_context context, 40 krb5_auth_context auth_context, 41 const krb5_data *inbuf, 42 krb5_data *outbuf, 43 /*krb5_replay_data*/ void *outdata) 44 { 45 krb5_error_code ret; 46 KRB_PRIV priv; 47 EncKrbPrivPart part; 48 size_t len; 49 krb5_data plain; 50 krb5_keyblock *key; 51 krb5_crypto crypto; 52 53 memset(&priv, 0, sizeof(priv)); 54 ret = decode_KRB_PRIV (inbuf->data, inbuf->length, &priv, &len); 55 if (ret) 56 goto failure; 57 if (priv.pvno != 5) { 58 krb5_clear_error_string (context); 59 ret = KRB5KRB_AP_ERR_BADVERSION; 60 goto failure; 61 } 62 if (priv.msg_type != krb_priv) { 63 krb5_clear_error_string (context); 64 ret = KRB5KRB_AP_ERR_MSG_TYPE; 65 goto failure; 66 } 67 68 /* XXX - Is this right? */ 69 70 if (auth_context->local_subkey) 71 key = auth_context->local_subkey; 72 else if (auth_context->remote_subkey) 73 key = auth_context->remote_subkey; 74 else 75 key = auth_context->keyblock; 76 77 ret = krb5_crypto_init(context, key, 0, &crypto); 78 if (ret) 79 goto failure; 80 ret = krb5_decrypt_EncryptedData(context, 81 crypto, 82 KRB5_KU_KRB_PRIV, 83 &priv.enc_part, 84 &plain); 85 krb5_crypto_destroy(context, crypto); 86 if (ret) 87 goto failure; 88 89 ret = decode_EncKrbPrivPart (plain.data, plain.length, &part, &len); 90 krb5_data_free (&plain); 91 if (ret) 92 goto failure; 93 94 /* check sender address */ 95 96 if (part.s_address 97 && auth_context->remote_address 98 && !krb5_address_compare (context, 99 auth_context->remote_address, 100 part.s_address)) { 101 krb5_clear_error_string (context); 102 ret = KRB5KRB_AP_ERR_BADADDR; 103 goto failure_part; 104 } 105 106 /* check receiver address */ 107 108 if (part.r_address 109 && auth_context->local_address 110 && !krb5_address_compare (context, 111 auth_context->local_address, 112 part.r_address)) { 113 krb5_clear_error_string (context); 114 ret = KRB5KRB_AP_ERR_BADADDR; 115 goto failure_part; 116 } 117 118 /* check timestamp */ 119 if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_TIME) { 120 krb5_timestamp sec; 121 122 krb5_timeofday (context, &sec); 123 if (part.timestamp == NULL || 124 part.usec == NULL || 125 abs(*part.timestamp - sec) > context->max_skew) { 126 krb5_clear_error_string (context); 127 ret = KRB5KRB_AP_ERR_SKEW; 128 goto failure_part; 129 } 130 } 131 132 /* XXX - check replay cache */ 133 134 /* check sequence number. since MIT krb5 cannot generate a sequence 135 number of zero but instead generates no sequence number, we accept that 136 */ 137 138 if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE) { 139 if ((part.seq_number == NULL 140 && auth_context->remote_seqnumber != 0) 141 || (part.seq_number != NULL 142 && *part.seq_number != auth_context->remote_seqnumber)) { 143 krb5_clear_error_string (context); 144 ret = KRB5KRB_AP_ERR_BADORDER; 145 goto failure_part; 146 } 147 auth_context->remote_seqnumber++; 148 } 149 150 ret = krb5_data_copy (outbuf, part.user_data.data, part.user_data.length); 151 if (ret) 152 goto failure_part; 153 154 free_EncKrbPrivPart (&part); 155 free_KRB_PRIV (&priv); 156 return 0; 157 158 failure_part: 159 free_EncKrbPrivPart (&part); 160 161 failure: 162 free_KRB_PRIV (&priv); 163 return ret; 164 } 165