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-rw-r--r--third_party/heimdal/lib/gssapi/krb5/unwrap.c468
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diff --git a/third_party/heimdal/lib/gssapi/krb5/unwrap.c b/third_party/heimdal/lib/gssapi/krb5/unwrap.c
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+/*
+ * Copyright (c) 1997 - 2004 Kungliga Tekniska Högskolan
+ * (Royal Institute of Technology, Stockholm, Sweden).
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * 3. Neither the name of the Institute nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include "gsskrb5_locl.h"
+
+#ifdef HEIM_WEAK_CRYPTO
+
+static OM_uint32
+unwrap_des
+ (OM_uint32 * minor_status,
+ const gsskrb5_ctx context_handle,
+ const gss_buffer_t input_message_buffer,
+ gss_buffer_t output_message_buffer,
+ int * conf_state,
+ gss_qop_t * qop_state,
+ krb5_keyblock *key
+ )
+{
+ u_char *p, *seq;
+ size_t len;
+ EVP_MD_CTX *md5;
+ u_char hash[16];
+ EVP_CIPHER_CTX des_ctx;
+ DES_key_schedule schedule;
+ DES_cblock deskey;
+ DES_cblock zero;
+ size_t i;
+ uint32_t seq_number;
+ size_t padlength;
+ OM_uint32 ret;
+ int cstate;
+ int cmp;
+ int token_len;
+
+ if (IS_DCE_STYLE(context_handle)) {
+ token_len = 22 + 8 + 15; /* 45 */
+ if (input_message_buffer->length < token_len)
+ return GSS_S_BAD_MECH;
+ } else {
+ token_len = input_message_buffer->length;
+ }
+
+ p = input_message_buffer->value;
+ ret = _gsskrb5_verify_header (&p,
+ token_len,
+ "\x02\x01",
+ GSS_KRB5_MECHANISM);
+ if (ret)
+ return ret;
+
+ len = (p - (u_char *)input_message_buffer->value)
+ + 22 + 8;
+ if (input_message_buffer->length < len)
+ return GSS_S_BAD_MECH;
+
+ if (memcmp (p, "\x00\x00", 2) != 0)
+ return GSS_S_BAD_SIG;
+ p += 2;
+ if (memcmp (p, "\x00\x00", 2) == 0) {
+ cstate = 1;
+ } else if (memcmp (p, "\xFF\xFF", 2) == 0) {
+ cstate = 0;
+ } else
+ return GSS_S_BAD_MIC;
+ p += 2;
+ if(conf_state != NULL)
+ *conf_state = cstate;
+ if (memcmp (p, "\xff\xff", 2) != 0)
+ return GSS_S_DEFECTIVE_TOKEN;
+ p += 2;
+ p += 16;
+
+ len = p - (u_char *)input_message_buffer->value;
+
+ if(cstate) {
+ /* decrypt data */
+ memcpy (&deskey, key->keyvalue.data, sizeof(deskey));
+ memset (&zero, 0, sizeof(zero));
+
+ for (i = 0; i < sizeof(deskey); ++i)
+ deskey[i] ^= 0xf0;
+
+
+ EVP_CIPHER_CTX_init(&des_ctx);
+ EVP_CipherInit_ex(&des_ctx, EVP_des_cbc(), NULL, deskey, zero, 0);
+ EVP_Cipher(&des_ctx, p, p, input_message_buffer->length - len);
+ EVP_CIPHER_CTX_cleanup(&des_ctx);
+
+ memset (&deskey, 0, sizeof(deskey));
+ }
+
+ if (IS_DCE_STYLE(context_handle)) {
+ padlength = 0;
+ } else {
+ /* check pad */
+ ret = _gssapi_verify_pad(input_message_buffer,
+ input_message_buffer->length - len - 8,
+ &padlength);
+ if (ret)
+ return ret;
+ }
+
+ md5 = EVP_MD_CTX_create();
+ EVP_DigestInit_ex(md5, EVP_md5(), NULL);
+ EVP_DigestUpdate(md5, p - 24, 8);
+ EVP_DigestUpdate(md5, p, input_message_buffer->length - len);
+ EVP_DigestFinal_ex(md5, hash, NULL);
+ EVP_MD_CTX_destroy(md5);
+
+ memset (&zero, 0, sizeof(zero));
+ memcpy (&deskey, key->keyvalue.data, sizeof(deskey));
+ DES_set_key_unchecked (&deskey, &schedule);
+ DES_cbc_cksum ((void *)hash, (void *)hash, sizeof(hash),
+ &schedule, &zero);
+ if (ct_memcmp (p - 8, hash, 8) != 0) {
+ memset_s(&deskey, sizeof(deskey), 0, sizeof(deskey));
+ memset_s(&schedule, sizeof(schedule), 0, sizeof(schedule));
+ return GSS_S_BAD_MIC;
+ }
+
+ /* verify sequence number */
+
+ HEIMDAL_MUTEX_lock(&context_handle->ctx_id_mutex);
+
+ p -= 16;
+
+ EVP_CIPHER_CTX_init(&des_ctx);
+ EVP_CipherInit_ex(&des_ctx, EVP_des_cbc(), NULL, key->keyvalue.data, hash, 0);
+ EVP_Cipher(&des_ctx, p, p, 8);
+ EVP_CIPHER_CTX_cleanup(&des_ctx);
+
+ memset (deskey, 0, sizeof(deskey));
+ memset (&schedule, 0, sizeof(schedule));
+
+ seq = p;
+ _gsskrb5_decode_om_uint32(seq, &seq_number);
+
+ if (context_handle->more_flags & LOCAL)
+ cmp = ct_memcmp(&seq[4], "\xff\xff\xff\xff", 4);
+ else
+ cmp = ct_memcmp(&seq[4], "\x00\x00\x00\x00", 4);
+
+ if (cmp != 0) {
+ HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex);
+ return GSS_S_BAD_MIC;
+ }
+
+ ret = _gssapi_msg_order_check(context_handle->order, seq_number);
+ if (ret) {
+ HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex);
+ return ret;
+ }
+
+ HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex);
+
+ /* copy out data */
+
+ output_message_buffer->length = input_message_buffer->length
+ - len - padlength - 8;
+ output_message_buffer->value = malloc(output_message_buffer->length);
+ if(output_message_buffer->length != 0 && output_message_buffer->value == NULL)
+ return GSS_S_FAILURE;
+ if (output_message_buffer->value != NULL)
+ memcpy (output_message_buffer->value,
+ p + 24,
+ output_message_buffer->length);
+ return GSS_S_COMPLETE;
+}
+#endif
+
+static OM_uint32
+unwrap_des3
+ (OM_uint32 * minor_status,
+ const gsskrb5_ctx context_handle,
+ krb5_context context,
+ const gss_buffer_t input_message_buffer,
+ gss_buffer_t output_message_buffer,
+ int * conf_state,
+ gss_qop_t * qop_state,
+ krb5_keyblock *key
+ )
+{
+ u_char *p;
+ size_t len;
+ u_char *seq;
+ krb5_data seq_data;
+ u_char cksum[20];
+ uint32_t seq_number;
+ size_t padlength;
+ OM_uint32 ret;
+ int cstate;
+ krb5_crypto crypto;
+ Checksum csum;
+ int cmp;
+ int token_len;
+
+ if (IS_DCE_STYLE(context_handle)) {
+ token_len = 34 + 8 + 15; /* 57 */
+ if (input_message_buffer->length < token_len)
+ return GSS_S_BAD_MECH;
+ } else {
+ token_len = input_message_buffer->length;
+ }
+
+ p = input_message_buffer->value;
+ ret = _gsskrb5_verify_header (&p,
+ token_len,
+ "\x02\x01",
+ GSS_KRB5_MECHANISM);
+ if (ret)
+ return ret;
+
+ len = (p - (u_char *)input_message_buffer->value)
+ + 34 + 8;
+ if (input_message_buffer->length < len)
+ return GSS_S_BAD_MECH;
+
+ if (ct_memcmp (p, "\x04\x00", 2) != 0) /* HMAC SHA1 DES3_KD */
+ return GSS_S_BAD_SIG;
+ p += 2;
+ if (ct_memcmp (p, "\x02\x00", 2) == 0) {
+ cstate = 1;
+ } else if (ct_memcmp (p, "\xff\xff", 2) == 0) {
+ cstate = 0;
+ } else
+ return GSS_S_BAD_MIC;
+ p += 2;
+ if(conf_state != NULL)
+ *conf_state = cstate;
+ if (ct_memcmp (p, "\xff\xff", 2) != 0)
+ return GSS_S_DEFECTIVE_TOKEN;
+ p += 2;
+ p += 28;
+
+ len = p - (u_char *)input_message_buffer->value;
+
+ if(cstate) {
+ /* decrypt data */
+ krb5_data tmp;
+
+ ret = krb5_crypto_init(context, key,
+ ETYPE_DES3_CBC_NONE, &crypto);
+ if (ret) {
+ *minor_status = ret;
+ return GSS_S_FAILURE;
+ }
+ ret = krb5_decrypt(context, crypto, KRB5_KU_USAGE_SEAL,
+ p, input_message_buffer->length - len, &tmp);
+ krb5_crypto_destroy(context, crypto);
+ if (ret) {
+ *minor_status = ret;
+ return GSS_S_FAILURE;
+ }
+ assert (tmp.length == input_message_buffer->length - len);
+
+ memcpy (p, tmp.data, tmp.length);
+ krb5_data_free(&tmp);
+ }
+
+ if (IS_DCE_STYLE(context_handle)) {
+ padlength = 0;
+ } else {
+ /* check pad */
+ ret = _gssapi_verify_pad(input_message_buffer,
+ input_message_buffer->length - len - 8,
+ &padlength);
+ if (ret)
+ return ret;
+ }
+
+ /* verify sequence number */
+
+ HEIMDAL_MUTEX_lock(&context_handle->ctx_id_mutex);
+
+ p -= 28;
+
+ ret = krb5_crypto_init(context, key,
+ ETYPE_DES3_CBC_NONE, &crypto);
+ if (ret) {
+ *minor_status = ret;
+ HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex);
+ return GSS_S_FAILURE;
+ }
+ {
+ DES_cblock ivec;
+
+ memcpy(&ivec, p + 8, 8);
+ ret = krb5_decrypt_ivec (context,
+ crypto,
+ KRB5_KU_USAGE_SEQ,
+ p, 8, &seq_data,
+ &ivec);
+ }
+ krb5_crypto_destroy (context, crypto);
+ if (ret) {
+ *minor_status = ret;
+ HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex);
+ return GSS_S_FAILURE;
+ }
+ if (seq_data.length != 8) {
+ krb5_data_free (&seq_data);
+ *minor_status = 0;
+ HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex);
+ return GSS_S_BAD_MIC;
+ }
+
+ seq = seq_data.data;
+ _gsskrb5_decode_om_uint32(seq, &seq_number);
+
+ if (context_handle->more_flags & LOCAL)
+ cmp = ct_memcmp(&seq[4], "\xff\xff\xff\xff", 4);
+ else
+ cmp = ct_memcmp(&seq[4], "\x00\x00\x00\x00", 4);
+
+ krb5_data_free (&seq_data);
+ if (cmp != 0) {
+ *minor_status = 0;
+ HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex);
+ return GSS_S_BAD_MIC;
+ }
+
+ ret = _gssapi_msg_order_check(context_handle->order, seq_number);
+ if (ret) {
+ *minor_status = 0;
+ HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex);
+ return ret;
+ }
+
+ HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex);
+
+ /* verify checksum */
+
+ memcpy (cksum, p + 8, 20);
+
+ memcpy (p + 20, p - 8, 8);
+
+ csum.cksumtype = CKSUMTYPE_HMAC_SHA1_DES3;
+ csum.checksum.length = 20;
+ csum.checksum.data = cksum;
+
+ ret = krb5_crypto_init(context, key, 0, &crypto);
+ if (ret) {
+ *minor_status = ret;
+ return GSS_S_FAILURE;
+ }
+
+ ret = krb5_verify_checksum (context, crypto,
+ KRB5_KU_USAGE_SIGN,
+ p + 20,
+ input_message_buffer->length - len + 8,
+ &csum);
+ krb5_crypto_destroy (context, crypto);
+ if (ret) {
+ *minor_status = ret;
+ return GSS_S_FAILURE;
+ }
+
+ /* copy out data */
+
+ output_message_buffer->length = input_message_buffer->length
+ - len - padlength - 8;
+ output_message_buffer->value = malloc(output_message_buffer->length);
+ if(output_message_buffer->length != 0 && output_message_buffer->value == NULL)
+ return GSS_S_FAILURE;
+ if (output_message_buffer->value != NULL)
+ memcpy (output_message_buffer->value,
+ p + 36,
+ output_message_buffer->length);
+ return GSS_S_COMPLETE;
+}
+
+OM_uint32 GSSAPI_CALLCONV _gsskrb5_unwrap
+ (OM_uint32 * minor_status,
+ gss_const_ctx_id_t context_handle,
+ const gss_buffer_t input_message_buffer,
+ gss_buffer_t output_message_buffer,
+ int * conf_state,
+ gss_qop_t * qop_state
+ )
+{
+ krb5_keyblock *key;
+ krb5_context context;
+ OM_uint32 ret;
+ gsskrb5_ctx ctx = (gsskrb5_ctx) context_handle;
+
+ output_message_buffer->value = NULL;
+ output_message_buffer->length = 0;
+ if (qop_state != NULL)
+ *qop_state = GSS_C_QOP_DEFAULT;
+
+ GSSAPI_KRB5_INIT (&context);
+
+ if (ctx->more_flags & IS_CFX)
+ return _gssapi_unwrap_cfx (minor_status, ctx, context,
+ input_message_buffer, output_message_buffer,
+ conf_state, qop_state);
+
+ HEIMDAL_MUTEX_lock(&ctx->ctx_id_mutex);
+ ret = _gsskrb5i_get_token_key(ctx, context, &key);
+ HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex);
+ if (ret) {
+ *minor_status = ret;
+ return GSS_S_FAILURE;
+ }
+
+ *minor_status = 0;
+
+ switch (key->keytype) {
+ case KRB5_ENCTYPE_DES_CBC_CRC :
+ case KRB5_ENCTYPE_DES_CBC_MD4 :
+ case KRB5_ENCTYPE_DES_CBC_MD5 :
+#ifdef HEIM_WEAK_CRYPTO
+ ret = unwrap_des (minor_status, ctx,
+ input_message_buffer, output_message_buffer,
+ conf_state, qop_state, key);
+#else
+ ret = GSS_S_FAILURE;
+#endif
+ break;
+ case KRB5_ENCTYPE_DES3_CBC_MD5 :
+ case KRB5_ENCTYPE_DES3_CBC_SHA1 :
+ ret = unwrap_des3 (minor_status, ctx, context,
+ input_message_buffer, output_message_buffer,
+ conf_state, qop_state, key);
+ break;
+ case KRB5_ENCTYPE_ARCFOUR_HMAC_MD5:
+ case KRB5_ENCTYPE_ARCFOUR_HMAC_MD5_56:
+ ret = _gssapi_unwrap_arcfour (minor_status, ctx, context,
+ input_message_buffer, output_message_buffer,
+ conf_state, qop_state, key);
+ break;
+ default :
+ abort();
+ break;
+ }
+ krb5_free_keyblock (context, key);
+ return ret;
+}
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