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 1.29 2001/06/18 02:46:15 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 if (auth_context->remote_subkey) 69 key = auth_context->remote_subkey; 70 else if (auth_context->local_subkey) 71 key = auth_context->local_subkey; 72 else 73 key = auth_context->keyblock; 74 75 ret = krb5_crypto_init(context, key, 0, &crypto); 76 if (ret) 77 goto failure; 78 ret = krb5_decrypt_EncryptedData(context, 79 crypto, 80 KRB5_KU_KRB_PRIV, 81 &priv.enc_part, 82 &plain); 83 krb5_crypto_destroy(context, crypto); 84 if (ret) 85 goto failure; 86 87 ret = decode_EncKrbPrivPart (plain.data, plain.length, &part, &len); 88 krb5_data_free (&plain); 89 if (ret) 90 goto failure; 91 92 /* check sender address */ 93 94 if (part.s_address 95 && auth_context->remote_address 96 && !krb5_address_compare (context, 97 auth_context->remote_address, 98 part.s_address)) { 99 krb5_clear_error_string (context); 100 ret = KRB5KRB_AP_ERR_BADADDR; 101 goto failure_part; 102 } 103 104 /* check receiver address */ 105 106 if (part.r_address 107 && auth_context->local_address 108 && !krb5_address_compare (context, 109 auth_context->local_address, 110 part.r_address)) { 111 krb5_clear_error_string (context); 112 ret = KRB5KRB_AP_ERR_BADADDR; 113 goto failure_part; 114 } 115 116 /* check timestamp */ 117 if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_TIME) { 118 krb5_timestamp sec; 119 120 krb5_timeofday (context, &sec); 121 if (part.timestamp == NULL || 122 part.usec == NULL || 123 abs(*part.timestamp - sec) > context->max_skew) { 124 krb5_clear_error_string (context); 125 ret = KRB5KRB_AP_ERR_SKEW; 126 goto failure_part; 127 } 128 } 129 130 /* XXX - check replay cache */ 131 132 /* check sequence number. since MIT krb5 cannot generate a sequence 133 number of zero but instead generates no sequence number, we accept that 134 */ 135 136 if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE) { 137 if ((part.seq_number == NULL 138 && auth_context->remote_seqnumber != 0) 139 || (part.seq_number != NULL 140 && *part.seq_number != auth_context->remote_seqnumber)) { 141 krb5_clear_error_string (context); 142 ret = KRB5KRB_AP_ERR_BADORDER; 143 goto failure_part; 144 } 145 auth_context->remote_seqnumber++; 146 } 147 148 ret = krb5_data_copy (outbuf, part.user_data.data, part.user_data.length); 149 if (ret) 150 goto failure_part; 151 152 free_EncKrbPrivPart (&part); 153 free_KRB_PRIV (&priv); 154 return 0; 155 156 failure_part: 157 free_EncKrbPrivPart (&part); 158 159 failure: 160 free_KRB_PRIV (&priv); 161 return ret; 162 } 163