1 /* 2 * Copyright (c) 1997 - 2003 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: mk_safe.c 13863 2004-05-25 21:46:46Z lha $"); 37 38 krb5_error_code KRB5_LIB_FUNCTION 39 krb5_mk_safe(krb5_context context, 40 krb5_auth_context auth_context, 41 const krb5_data *userdata, 42 krb5_data *outbuf, 43 krb5_replay_data *outdata) 44 { 45 krb5_error_code ret; 46 KRB_SAFE s; 47 u_char *buf = NULL; 48 size_t buf_size; 49 size_t len; 50 krb5_crypto crypto; 51 krb5_keyblock *key; 52 krb5_replay_data rdata; 53 54 if ((auth_context->flags & 55 (KRB5_AUTH_CONTEXT_RET_TIME | KRB5_AUTH_CONTEXT_RET_SEQUENCE)) && 56 outdata == NULL) 57 return KRB5_RC_REQUIRED; /* XXX better error, MIT returns this */ 58 59 if (auth_context->local_subkey) 60 key = auth_context->local_subkey; 61 else if (auth_context->remote_subkey) 62 key = auth_context->remote_subkey; 63 else 64 key = auth_context->keyblock; 65 66 s.pvno = 5; 67 s.msg_type = krb_safe; 68 69 memset(&rdata, 0, sizeof(rdata)); 70 71 s.safe_body.user_data = *userdata; 72 73 krb5_us_timeofday (context, &rdata.timestamp, &rdata.usec); 74 75 if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_TIME) { 76 s.safe_body.timestamp = &rdata.timestamp; 77 s.safe_body.usec = &rdata.usec; 78 } else { 79 s.safe_body.timestamp = NULL; 80 s.safe_body.usec = NULL; 81 } 82 83 if (auth_context->flags & KRB5_AUTH_CONTEXT_RET_TIME) { 84 outdata->timestamp = rdata.timestamp; 85 outdata->usec = rdata.usec; 86 } 87 88 if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE) { 89 rdata.seq = auth_context->local_seqnumber; 90 s.safe_body.seq_number = &rdata.seq; 91 } else 92 s.safe_body.seq_number = NULL; 93 94 if (auth_context->flags & KRB5_AUTH_CONTEXT_RET_SEQUENCE) 95 outdata->seq = auth_context->local_seqnumber; 96 97 s.safe_body.s_address = auth_context->local_address; 98 s.safe_body.r_address = auth_context->remote_address; 99 100 s.cksum.cksumtype = 0; 101 s.cksum.checksum.data = NULL; 102 s.cksum.checksum.length = 0; 103 104 ASN1_MALLOC_ENCODE(KRB_SAFE, buf, buf_size, &s, &len, ret); 105 if (ret) 106 return ret; 107 if(buf_size != len) 108 krb5_abortx(context, "internal error in ASN.1 encoder"); 109 ret = krb5_crypto_init(context, key, 0, &crypto); 110 if (ret) { 111 free (buf); 112 return ret; 113 } 114 ret = krb5_create_checksum(context, 115 crypto, 116 KRB5_KU_KRB_SAFE_CKSUM, 117 0, 118 buf, 119 len, 120 &s.cksum); 121 krb5_crypto_destroy(context, crypto); 122 if (ret) { 123 free (buf); 124 return ret; 125 } 126 127 free(buf); 128 ASN1_MALLOC_ENCODE(KRB_SAFE, buf, buf_size, &s, &len, ret); 129 free_Checksum (&s.cksum); 130 if(ret) 131 return ret; 132 if(buf_size != len) 133 krb5_abortx(context, "internal error in ASN.1 encoder"); 134 135 outbuf->length = len; 136 outbuf->data = buf; 137 if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE) 138 auth_context->local_seqnumber = 139 (auth_context->local_seqnumber + 1) & 0xFFFFFFFF; 140 return 0; 141 } 142