1 /* 2 * Copyright (c) 2007 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/gsskrb5_locl.h" 35 36 RCSID("$Id: prf.c 21129 2007-06-18 20:28:44Z lha $"); 37 38 OM_uint32 39 _gsskrb5_pseudo_random(OM_uint32 *minor_status, 40 gss_ctx_id_t context_handle, 41 int prf_key, 42 const gss_buffer_t prf_in, 43 ssize_t desired_output_len, 44 gss_buffer_t prf_out) 45 { 46 gsskrb5_ctx ctx = (gsskrb5_ctx)context_handle; 47 krb5_context context; 48 krb5_error_code ret; 49 krb5_crypto crypto; 50 krb5_data input, output; 51 uint32_t num; 52 unsigned char *p; 53 krb5_keyblock *key = NULL; 54 55 if (ctx == NULL) { 56 *minor_status = 0; 57 return GSS_S_NO_CONTEXT; 58 } 59 60 if (desired_output_len <= 0) { 61 *minor_status = 0; 62 return GSS_S_FAILURE; 63 } 64 65 GSSAPI_KRB5_INIT (&context); 66 67 switch(prf_key) { 68 case GSS_C_PRF_KEY_FULL: 69 _gsskrb5i_get_acceptor_subkey(ctx, context, &key); 70 break; 71 case GSS_C_PRF_KEY_PARTIAL: 72 _gsskrb5i_get_initiator_subkey(ctx, context, &key); 73 break; 74 default: 75 _gsskrb5_set_status("unknown kerberos prf_key"); 76 *minor_status = 0; 77 return GSS_S_FAILURE; 78 } 79 80 if (key == NULL) { 81 _gsskrb5_set_status("no prf_key found"); 82 *minor_status = 0; 83 return GSS_S_FAILURE; 84 } 85 86 ret = krb5_crypto_init(context, key, 0, &crypto); 87 krb5_free_keyblock (context, key); 88 if (ret) { 89 *minor_status = ret; 90 return GSS_S_FAILURE; 91 } 92 93 prf_out->value = malloc(desired_output_len); 94 if (prf_out->value == NULL) { 95 _gsskrb5_set_status("Out of memory"); 96 *minor_status = GSS_KRB5_S_KG_INPUT_TOO_LONG; 97 krb5_crypto_destroy(context, crypto); 98 return GSS_S_FAILURE; 99 } 100 prf_out->length = desired_output_len; 101 102 HEIMDAL_MUTEX_lock(&ctx->ctx_id_mutex); 103 104 input.length = prf_in->length + 4; 105 input.data = malloc(prf_in->length + 4); 106 if (input.data == NULL) { 107 OM_uint32 junk; 108 _gsskrb5_set_status("Out of memory"); 109 *minor_status = GSS_KRB5_S_KG_INPUT_TOO_LONG; 110 gss_release_buffer(&junk, prf_out); 111 krb5_crypto_destroy(context, crypto); 112 HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex); 113 return GSS_S_FAILURE; 114 } 115 memcpy(((unsigned char *)input.data) + 4, prf_in->value, prf_in->length); 116 117 num = 0; 118 p = prf_out->value; 119 while(desired_output_len > 0) { 120 _gsskrb5_encode_om_uint32(num, input.data); 121 ret = krb5_crypto_prf(context, crypto, &input, &output); 122 if (ret) { 123 OM_uint32 junk; 124 *minor_status = ret; 125 free(input.data); 126 gss_release_buffer(&junk, prf_out); 127 krb5_crypto_destroy(context, crypto); 128 HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex); 129 return GSS_S_FAILURE; 130 } 131 memcpy(p, output.data, min(desired_output_len, output.length)); 132 p += output.length; 133 desired_output_len -= output.length; 134 krb5_data_free(&output); 135 num++; 136 } 137 138 krb5_crypto_destroy(context, crypto); 139 140 HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex); 141 142 return GSS_S_COMPLETE; 143 } 144