1178825Sdfr/* 2178825Sdfr * Copyright (c) 1997 - 2003 Kungliga Tekniska H�gskolan 3178825Sdfr * (Royal Institute of Technology, Stockholm, Sweden). 4178825Sdfr * All rights reserved. 5178825Sdfr * 6178825Sdfr * Redistribution and use in source and binary forms, with or without 7178825Sdfr * modification, are permitted provided that the following conditions 8178825Sdfr * are met: 9178825Sdfr * 10178825Sdfr * 1. Redistributions of source code must retain the above copyright 11178825Sdfr * notice, this list of conditions and the following disclaimer. 12178825Sdfr * 13178825Sdfr * 2. Redistributions in binary form must reproduce the above copyright 14178825Sdfr * notice, this list of conditions and the following disclaimer in the 15178825Sdfr * documentation and/or other materials provided with the distribution. 16178825Sdfr * 17178825Sdfr * 3. Neither the name of the Institute nor the names of its contributors 18178825Sdfr * may be used to endorse or promote products derived from this software 19178825Sdfr * without specific prior written permission. 20178825Sdfr * 21178825Sdfr * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND 22178825Sdfr * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23178825Sdfr * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24178825Sdfr * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE 25178825Sdfr * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26178825Sdfr * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27178825Sdfr * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28178825Sdfr * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29178825Sdfr * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30178825Sdfr * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31178825Sdfr * SUCH DAMAGE. 32178825Sdfr */ 33178825Sdfr 34178825Sdfr#include "krb5/gsskrb5_locl.h" 35178825Sdfr 36178825SdfrRCSID("$Id: verify_mic.c 19031 2006-11-13 18:02:57Z lha $"); 37178825Sdfr 38178825Sdfrstatic OM_uint32 39178825Sdfrverify_mic_des 40178825Sdfr (OM_uint32 * minor_status, 41178825Sdfr const gsskrb5_ctx context_handle, 42178825Sdfr krb5_context context, 43178825Sdfr const gss_buffer_t message_buffer, 44178825Sdfr const gss_buffer_t token_buffer, 45178825Sdfr gss_qop_t * qop_state, 46178825Sdfr krb5_keyblock *key, 47178825Sdfr char *type 48178825Sdfr ) 49178825Sdfr{ 50178825Sdfr u_char *p; 51178825Sdfr MD5_CTX md5; 52178825Sdfr u_char hash[16], *seq; 53178825Sdfr DES_key_schedule schedule; 54178825Sdfr DES_cblock zero; 55178825Sdfr DES_cblock deskey; 56178825Sdfr uint32_t seq_number; 57178825Sdfr OM_uint32 ret; 58178825Sdfr int cmp; 59178825Sdfr 60178825Sdfr p = token_buffer->value; 61178825Sdfr ret = _gsskrb5_verify_header (&p, 62178825Sdfr token_buffer->length, 63178825Sdfr type, 64178825Sdfr GSS_KRB5_MECHANISM); 65178825Sdfr if (ret) 66178825Sdfr return ret; 67178825Sdfr 68178825Sdfr if (memcmp(p, "\x00\x00", 2) != 0) 69178825Sdfr return GSS_S_BAD_SIG; 70178825Sdfr p += 2; 71178825Sdfr if (memcmp (p, "\xff\xff\xff\xff", 4) != 0) 72178825Sdfr return GSS_S_BAD_MIC; 73178825Sdfr p += 4; 74178825Sdfr p += 16; 75178825Sdfr 76178825Sdfr /* verify checksum */ 77178825Sdfr MD5_Init (&md5); 78178825Sdfr MD5_Update (&md5, p - 24, 8); 79178825Sdfr MD5_Update (&md5, message_buffer->value, 80178825Sdfr message_buffer->length); 81178825Sdfr MD5_Final (hash, &md5); 82178825Sdfr 83178825Sdfr memset (&zero, 0, sizeof(zero)); 84178825Sdfr memcpy (&deskey, key->keyvalue.data, sizeof(deskey)); 85178825Sdfr 86178825Sdfr DES_set_key (&deskey, &schedule); 87178825Sdfr DES_cbc_cksum ((void *)hash, (void *)hash, sizeof(hash), 88178825Sdfr &schedule, &zero); 89178825Sdfr if (memcmp (p - 8, hash, 8) != 0) { 90178825Sdfr memset (deskey, 0, sizeof(deskey)); 91178825Sdfr memset (&schedule, 0, sizeof(schedule)); 92178825Sdfr return GSS_S_BAD_MIC; 93178825Sdfr } 94178825Sdfr 95178825Sdfr /* verify sequence number */ 96178825Sdfr 97178825Sdfr HEIMDAL_MUTEX_lock(&context_handle->ctx_id_mutex); 98178825Sdfr 99178825Sdfr p -= 16; 100178825Sdfr DES_set_key (&deskey, &schedule); 101178825Sdfr DES_cbc_encrypt ((void *)p, (void *)p, 8, 102178825Sdfr &schedule, (DES_cblock *)hash, DES_DECRYPT); 103178825Sdfr 104178825Sdfr memset (deskey, 0, sizeof(deskey)); 105178825Sdfr memset (&schedule, 0, sizeof(schedule)); 106178825Sdfr 107178825Sdfr seq = p; 108178825Sdfr _gsskrb5_decode_om_uint32(seq, &seq_number); 109178825Sdfr 110178825Sdfr if (context_handle->more_flags & LOCAL) 111178825Sdfr cmp = memcmp(&seq[4], "\xff\xff\xff\xff", 4); 112178825Sdfr else 113178825Sdfr cmp = memcmp(&seq[4], "\x00\x00\x00\x00", 4); 114178825Sdfr 115178825Sdfr if (cmp != 0) { 116178825Sdfr HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex); 117178825Sdfr return GSS_S_BAD_MIC; 118178825Sdfr } 119178825Sdfr 120178825Sdfr ret = _gssapi_msg_order_check(context_handle->order, seq_number); 121178825Sdfr if (ret) { 122178825Sdfr HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex); 123178825Sdfr return ret; 124178825Sdfr } 125178825Sdfr 126178825Sdfr HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex); 127178825Sdfr 128178825Sdfr return GSS_S_COMPLETE; 129178825Sdfr} 130178825Sdfr 131178825Sdfrstatic OM_uint32 132178825Sdfrverify_mic_des3 133178825Sdfr (OM_uint32 * minor_status, 134178825Sdfr const gsskrb5_ctx context_handle, 135178825Sdfr krb5_context context, 136178825Sdfr const gss_buffer_t message_buffer, 137178825Sdfr const gss_buffer_t token_buffer, 138178825Sdfr gss_qop_t * qop_state, 139178825Sdfr krb5_keyblock *key, 140178825Sdfr char *type 141178825Sdfr ) 142178825Sdfr{ 143178825Sdfr u_char *p; 144178825Sdfr u_char *seq; 145178825Sdfr uint32_t seq_number; 146178825Sdfr OM_uint32 ret; 147178825Sdfr krb5_crypto crypto; 148178825Sdfr krb5_data seq_data; 149178825Sdfr int cmp, docompat; 150178825Sdfr Checksum csum; 151178825Sdfr char *tmp; 152178825Sdfr char ivec[8]; 153178825Sdfr 154178825Sdfr p = token_buffer->value; 155178825Sdfr ret = _gsskrb5_verify_header (&p, 156178825Sdfr token_buffer->length, 157178825Sdfr type, 158178825Sdfr GSS_KRB5_MECHANISM); 159178825Sdfr if (ret) 160178825Sdfr return ret; 161178825Sdfr 162178825Sdfr if (memcmp(p, "\x04\x00", 2) != 0) /* SGN_ALG = HMAC SHA1 DES3-KD */ 163178825Sdfr return GSS_S_BAD_SIG; 164178825Sdfr p += 2; 165178825Sdfr if (memcmp (p, "\xff\xff\xff\xff", 4) != 0) 166178825Sdfr return GSS_S_BAD_MIC; 167178825Sdfr p += 4; 168178825Sdfr 169178825Sdfr ret = krb5_crypto_init(context, key, 170178825Sdfr ETYPE_DES3_CBC_NONE, &crypto); 171178825Sdfr if (ret){ 172178825Sdfr *minor_status = ret; 173178825Sdfr return GSS_S_FAILURE; 174178825Sdfr } 175178825Sdfr 176178825Sdfr /* verify sequence number */ 177178825Sdfr docompat = 0; 178178825Sdfrretry: 179178825Sdfr if (docompat) 180178825Sdfr memset(ivec, 0, 8); 181178825Sdfr else 182178825Sdfr memcpy(ivec, p + 8, 8); 183178825Sdfr 184178825Sdfr ret = krb5_decrypt_ivec (context, 185178825Sdfr crypto, 186178825Sdfr KRB5_KU_USAGE_SEQ, 187178825Sdfr p, 8, &seq_data, ivec); 188178825Sdfr if (ret) { 189178825Sdfr if (docompat++) { 190178825Sdfr krb5_crypto_destroy (context, crypto); 191178825Sdfr *minor_status = ret; 192178825Sdfr return GSS_S_FAILURE; 193178825Sdfr } else 194178825Sdfr goto retry; 195178825Sdfr } 196178825Sdfr 197178825Sdfr if (seq_data.length != 8) { 198178825Sdfr krb5_data_free (&seq_data); 199178825Sdfr if (docompat++) { 200178825Sdfr krb5_crypto_destroy (context, crypto); 201178825Sdfr return GSS_S_BAD_MIC; 202178825Sdfr } else 203178825Sdfr goto retry; 204178825Sdfr } 205178825Sdfr 206178825Sdfr HEIMDAL_MUTEX_lock(&context_handle->ctx_id_mutex); 207178825Sdfr 208178825Sdfr seq = seq_data.data; 209178825Sdfr _gsskrb5_decode_om_uint32(seq, &seq_number); 210178825Sdfr 211178825Sdfr if (context_handle->more_flags & LOCAL) 212178825Sdfr cmp = memcmp(&seq[4], "\xff\xff\xff\xff", 4); 213178825Sdfr else 214178825Sdfr cmp = memcmp(&seq[4], "\x00\x00\x00\x00", 4); 215178825Sdfr 216178825Sdfr krb5_data_free (&seq_data); 217178825Sdfr if (cmp != 0) { 218178825Sdfr krb5_crypto_destroy (context, crypto); 219178825Sdfr *minor_status = 0; 220178825Sdfr HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex); 221178825Sdfr return GSS_S_BAD_MIC; 222178825Sdfr } 223178825Sdfr 224178825Sdfr ret = _gssapi_msg_order_check(context_handle->order, seq_number); 225178825Sdfr if (ret) { 226178825Sdfr krb5_crypto_destroy (context, crypto); 227178825Sdfr *minor_status = 0; 228178825Sdfr HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex); 229178825Sdfr return ret; 230178825Sdfr } 231178825Sdfr 232178825Sdfr /* verify checksum */ 233178825Sdfr 234178825Sdfr tmp = malloc (message_buffer->length + 8); 235178825Sdfr if (tmp == NULL) { 236178825Sdfr krb5_crypto_destroy (context, crypto); 237178825Sdfr HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex); 238178825Sdfr *minor_status = ENOMEM; 239178825Sdfr return GSS_S_FAILURE; 240178825Sdfr } 241178825Sdfr 242178825Sdfr memcpy (tmp, p - 8, 8); 243178825Sdfr memcpy (tmp + 8, message_buffer->value, message_buffer->length); 244178825Sdfr 245178825Sdfr csum.cksumtype = CKSUMTYPE_HMAC_SHA1_DES3; 246178825Sdfr csum.checksum.length = 20; 247178825Sdfr csum.checksum.data = p + 8; 248178825Sdfr 249178825Sdfr ret = krb5_verify_checksum (context, crypto, 250178825Sdfr KRB5_KU_USAGE_SIGN, 251178825Sdfr tmp, message_buffer->length + 8, 252178825Sdfr &csum); 253178825Sdfr free (tmp); 254178825Sdfr if (ret) { 255178825Sdfr krb5_crypto_destroy (context, crypto); 256178825Sdfr *minor_status = ret; 257178825Sdfr HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex); 258178825Sdfr return GSS_S_BAD_MIC; 259178825Sdfr } 260178825Sdfr HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex); 261178825Sdfr 262178825Sdfr krb5_crypto_destroy (context, crypto); 263178825Sdfr return GSS_S_COMPLETE; 264178825Sdfr} 265178825Sdfr 266178825SdfrOM_uint32 267178825Sdfr_gsskrb5_verify_mic_internal 268178825Sdfr (OM_uint32 * minor_status, 269178825Sdfr const gsskrb5_ctx context_handle, 270178825Sdfr krb5_context context, 271178825Sdfr const gss_buffer_t message_buffer, 272178825Sdfr const gss_buffer_t token_buffer, 273178825Sdfr gss_qop_t * qop_state, 274178825Sdfr char * type 275178825Sdfr ) 276178825Sdfr{ 277178825Sdfr krb5_keyblock *key; 278178825Sdfr OM_uint32 ret; 279178825Sdfr krb5_keytype keytype; 280178825Sdfr 281178825Sdfr HEIMDAL_MUTEX_lock(&context_handle->ctx_id_mutex); 282178825Sdfr ret = _gsskrb5i_get_token_key(context_handle, context, &key); 283178825Sdfr HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex); 284178825Sdfr if (ret) { 285178825Sdfr *minor_status = ret; 286178825Sdfr return GSS_S_FAILURE; 287178825Sdfr } 288178825Sdfr *minor_status = 0; 289178825Sdfr krb5_enctype_to_keytype (context, key->keytype, &keytype); 290178825Sdfr switch (keytype) { 291178825Sdfr case KEYTYPE_DES : 292178825Sdfr ret = verify_mic_des (minor_status, context_handle, context, 293178825Sdfr message_buffer, token_buffer, qop_state, key, 294178825Sdfr type); 295178825Sdfr break; 296178825Sdfr case KEYTYPE_DES3 : 297178825Sdfr ret = verify_mic_des3 (minor_status, context_handle, context, 298178825Sdfr message_buffer, token_buffer, qop_state, key, 299178825Sdfr type); 300178825Sdfr break; 301178825Sdfr case KEYTYPE_ARCFOUR : 302178825Sdfr case KEYTYPE_ARCFOUR_56 : 303178825Sdfr ret = _gssapi_verify_mic_arcfour (minor_status, context_handle, 304178825Sdfr context, 305178825Sdfr message_buffer, token_buffer, 306178825Sdfr qop_state, key, type); 307178825Sdfr break; 308178825Sdfr default : 309178825Sdfr ret = _gssapi_verify_mic_cfx (minor_status, context_handle, 310178825Sdfr context, 311178825Sdfr message_buffer, token_buffer, qop_state, 312178825Sdfr key); 313178825Sdfr break; 314178825Sdfr } 315178825Sdfr krb5_free_keyblock (context, key); 316178825Sdfr 317178825Sdfr return ret; 318178825Sdfr} 319178825Sdfr 320178825SdfrOM_uint32 321178825Sdfr_gsskrb5_verify_mic 322178825Sdfr (OM_uint32 * minor_status, 323178825Sdfr const gss_ctx_id_t context_handle, 324178825Sdfr const gss_buffer_t message_buffer, 325178825Sdfr const gss_buffer_t token_buffer, 326178825Sdfr gss_qop_t * qop_state 327178825Sdfr ) 328178825Sdfr{ 329178825Sdfr krb5_context context; 330178825Sdfr OM_uint32 ret; 331178825Sdfr 332178825Sdfr GSSAPI_KRB5_INIT (&context); 333178825Sdfr 334178825Sdfr if (qop_state != NULL) 335178825Sdfr *qop_state = GSS_C_QOP_DEFAULT; 336178825Sdfr 337178825Sdfr ret = _gsskrb5_verify_mic_internal(minor_status, 338178825Sdfr (gsskrb5_ctx)context_handle, 339178825Sdfr context, 340178825Sdfr message_buffer, token_buffer, 341178825Sdfr qop_state, "\x01\x01"); 342178825Sdfr 343178825Sdfr return ret; 344178825Sdfr} 345