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-rw-r--r--crypto/heimdal/lib/gssapi/krb5/cfx.c878
1 files changed, 878 insertions, 0 deletions
diff --git a/crypto/heimdal/lib/gssapi/krb5/cfx.c b/crypto/heimdal/lib/gssapi/krb5/cfx.c
new file mode 100644
index 0000000..6452f80
--- /dev/null
+++ b/crypto/heimdal/lib/gssapi/krb5/cfx.c
@@ -0,0 +1,878 @@
+/*
+ * Copyright (c) 2003, PADL Software Pty Ltd.
+ * 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 PADL Software 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 PADL SOFTWARE 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 PADL SOFTWARE 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 "krb5/gsskrb5_locl.h"
+
+RCSID("$Id: cfx.c 19031 2006-11-13 18:02:57Z lha $");
+
+/*
+ * Implementation of draft-ietf-krb-wg-gssapi-cfx-06.txt
+ */
+
+#define CFXSentByAcceptor (1 << 0)
+#define CFXSealed (1 << 1)
+#define CFXAcceptorSubkey (1 << 2)
+
+krb5_error_code
+_gsskrb5cfx_wrap_length_cfx(krb5_context context,
+ krb5_crypto crypto,
+ int conf_req_flag,
+ size_t input_length,
+ size_t *output_length,
+ size_t *cksumsize,
+ uint16_t *padlength)
+{
+ krb5_error_code ret;
+ krb5_cksumtype type;
+
+ /* 16-byte header is always first */
+ *output_length = sizeof(gss_cfx_wrap_token_desc);
+ *padlength = 0;
+
+ ret = krb5_crypto_get_checksum_type(context, crypto, &type);
+ if (ret)
+ return ret;
+
+ ret = krb5_checksumsize(context, type, cksumsize);
+ if (ret)
+ return ret;
+
+ if (conf_req_flag) {
+ size_t padsize;
+
+ /* Header is concatenated with data before encryption */
+ input_length += sizeof(gss_cfx_wrap_token_desc);
+
+ ret = krb5_crypto_getpadsize(context, crypto, &padsize);
+ if (ret) {
+ return ret;
+ }
+ if (padsize > 1) {
+ /* XXX check this */
+ *padlength = padsize - (input_length % padsize);
+
+ /* We add the pad ourselves (noted here for completeness only) */
+ input_length += *padlength;
+ }
+
+ *output_length += krb5_get_wrapped_length(context,
+ crypto, input_length);
+ } else {
+ /* Checksum is concatenated with data */
+ *output_length += input_length + *cksumsize;
+ }
+
+ assert(*output_length > input_length);
+
+ return 0;
+}
+
+krb5_error_code
+_gsskrb5cfx_max_wrap_length_cfx(krb5_context context,
+ krb5_crypto crypto,
+ int conf_req_flag,
+ size_t input_length,
+ OM_uint32 *output_length)
+{
+ krb5_error_code ret;
+
+ *output_length = 0;
+
+ /* 16-byte header is always first */
+ if (input_length < 16)
+ return 0;
+ input_length -= 16;
+
+ if (conf_req_flag) {
+ size_t wrapped_size, sz;
+
+ wrapped_size = input_length + 1;
+ do {
+ wrapped_size--;
+ sz = krb5_get_wrapped_length(context,
+ crypto, wrapped_size);
+ } while (wrapped_size && sz > input_length);
+ if (wrapped_size == 0) {
+ *output_length = 0;
+ return 0;
+ }
+
+ /* inner header */
+ if (wrapped_size < 16) {
+ *output_length = 0;
+ return 0;
+ }
+ wrapped_size -= 16;
+
+ *output_length = wrapped_size;
+ } else {
+ krb5_cksumtype type;
+ size_t cksumsize;
+
+ ret = krb5_crypto_get_checksum_type(context, crypto, &type);
+ if (ret)
+ return ret;
+
+ ret = krb5_checksumsize(context, type, &cksumsize);
+ if (ret)
+ return ret;
+
+ if (input_length < cksumsize)
+ return 0;
+
+ /* Checksum is concatenated with data */
+ *output_length = input_length - cksumsize;
+ }
+
+ return 0;
+}
+
+
+OM_uint32 _gssapi_wrap_size_cfx(OM_uint32 *minor_status,
+ const gsskrb5_ctx context_handle,
+ krb5_context context,
+ int conf_req_flag,
+ gss_qop_t qop_req,
+ OM_uint32 req_output_size,
+ OM_uint32 *max_input_size,
+ krb5_keyblock *key)
+{
+ krb5_error_code ret;
+ krb5_crypto crypto;
+
+ ret = krb5_crypto_init(context, key, 0, &crypto);
+ if (ret != 0) {
+ *minor_status = ret;
+ return GSS_S_FAILURE;
+ }
+
+ ret = _gsskrb5cfx_max_wrap_length_cfx(context, crypto, conf_req_flag,
+ req_output_size, max_input_size);
+ if (ret != 0) {
+ *minor_status = ret;
+ krb5_crypto_destroy(context, crypto);
+ return GSS_S_FAILURE;
+ }
+
+ krb5_crypto_destroy(context, crypto);
+
+ return GSS_S_COMPLETE;
+}
+
+/*
+ * Rotate "rrc" bytes to the front or back
+ */
+
+static krb5_error_code
+rrc_rotate(void *data, size_t len, uint16_t rrc, krb5_boolean unrotate)
+{
+ u_char *tmp, buf[256];
+ size_t left;
+
+ if (len == 0)
+ return 0;
+
+ rrc %= len;
+
+ if (rrc == 0)
+ return 0;
+
+ left = len - rrc;
+
+ if (rrc <= sizeof(buf)) {
+ tmp = buf;
+ } else {
+ tmp = malloc(rrc);
+ if (tmp == NULL)
+ return ENOMEM;
+ }
+
+ if (unrotate) {
+ memcpy(tmp, data, rrc);
+ memmove(data, (u_char *)data + rrc, left);
+ memcpy((u_char *)data + left, tmp, rrc);
+ } else {
+ memcpy(tmp, (u_char *)data + left, rrc);
+ memmove((u_char *)data + rrc, data, left);
+ memcpy(data, tmp, rrc);
+ }
+
+ if (rrc > sizeof(buf))
+ free(tmp);
+
+ return 0;
+}
+
+OM_uint32 _gssapi_wrap_cfx(OM_uint32 *minor_status,
+ const gsskrb5_ctx context_handle,
+ krb5_context context,
+ int conf_req_flag,
+ gss_qop_t qop_req,
+ const gss_buffer_t input_message_buffer,
+ int *conf_state,
+ gss_buffer_t output_message_buffer,
+ krb5_keyblock *key)
+{
+ krb5_crypto crypto;
+ gss_cfx_wrap_token token;
+ krb5_error_code ret;
+ unsigned usage;
+ krb5_data cipher;
+ size_t wrapped_len, cksumsize;
+ uint16_t padlength, rrc = 0;
+ int32_t seq_number;
+ u_char *p;
+
+ ret = krb5_crypto_init(context, key, 0, &crypto);
+ if (ret != 0) {
+ *minor_status = ret;
+ return GSS_S_FAILURE;
+ }
+
+ ret = _gsskrb5cfx_wrap_length_cfx(context,
+ crypto, conf_req_flag,
+ input_message_buffer->length,
+ &wrapped_len, &cksumsize, &padlength);
+ if (ret != 0) {
+ *minor_status = ret;
+ krb5_crypto_destroy(context, crypto);
+ return GSS_S_FAILURE;
+ }
+
+ /* Always rotate encrypted token (if any) and checksum to header */
+ rrc = (conf_req_flag ? sizeof(*token) : 0) + (uint16_t)cksumsize;
+
+ output_message_buffer->length = wrapped_len;
+ output_message_buffer->value = malloc(output_message_buffer->length);
+ if (output_message_buffer->value == NULL) {
+ *minor_status = ENOMEM;
+ krb5_crypto_destroy(context, crypto);
+ return GSS_S_FAILURE;
+ }
+
+ p = output_message_buffer->value;
+ token = (gss_cfx_wrap_token)p;
+ token->TOK_ID[0] = 0x05;
+ token->TOK_ID[1] = 0x04;
+ token->Flags = 0;
+ token->Filler = 0xFF;
+ if ((context_handle->more_flags & LOCAL) == 0)
+ token->Flags |= CFXSentByAcceptor;
+ if (context_handle->more_flags & ACCEPTOR_SUBKEY)
+ token->Flags |= CFXAcceptorSubkey;
+ if (conf_req_flag) {
+ /*
+ * In Wrap tokens with confidentiality, the EC field is
+ * used to encode the size (in bytes) of the random filler.
+ */
+ token->Flags |= CFXSealed;
+ token->EC[0] = (padlength >> 8) & 0xFF;
+ token->EC[1] = (padlength >> 0) & 0xFF;
+ } else {
+ /*
+ * In Wrap tokens without confidentiality, the EC field is
+ * used to encode the size (in bytes) of the trailing
+ * checksum.
+ *
+ * This is not used in the checksum calcuation itself,
+ * because the checksum length could potentially vary
+ * depending on the data length.
+ */
+ token->EC[0] = 0;
+ token->EC[1] = 0;
+ }
+
+ /*
+ * In Wrap tokens that provide for confidentiality, the RRC
+ * field in the header contains the hex value 00 00 before
+ * encryption.
+ *
+ * In Wrap tokens that do not provide for confidentiality,
+ * both the EC and RRC fields in the appended checksum
+ * contain the hex value 00 00 for the purpose of calculating
+ * the checksum.
+ */
+ token->RRC[0] = 0;
+ token->RRC[1] = 0;
+
+ HEIMDAL_MUTEX_lock(&context_handle->ctx_id_mutex);
+ krb5_auth_con_getlocalseqnumber(context,
+ context_handle->auth_context,
+ &seq_number);
+ _gsskrb5_encode_be_om_uint32(0, &token->SND_SEQ[0]);
+ _gsskrb5_encode_be_om_uint32(seq_number, &token->SND_SEQ[4]);
+ krb5_auth_con_setlocalseqnumber(context,
+ context_handle->auth_context,
+ ++seq_number);
+ HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex);
+
+ /*
+ * If confidentiality is requested, the token header is
+ * appended to the plaintext before encryption; the resulting
+ * token is {"header" | encrypt(plaintext | pad | "header")}.
+ *
+ * If no confidentiality is requested, the checksum is
+ * calculated over the plaintext concatenated with the
+ * token header.
+ */
+ if (context_handle->more_flags & LOCAL) {
+ usage = KRB5_KU_USAGE_INITIATOR_SEAL;
+ } else {
+ usage = KRB5_KU_USAGE_ACCEPTOR_SEAL;
+ }
+
+ if (conf_req_flag) {
+ /*
+ * Any necessary padding is added here to ensure that the
+ * encrypted token header is always at the end of the
+ * ciphertext.
+ *
+ * The specification does not require that the padding
+ * bytes are initialized.
+ */
+ p += sizeof(*token);
+ memcpy(p, input_message_buffer->value, input_message_buffer->length);
+ memset(p + input_message_buffer->length, 0xFF, padlength);
+ memcpy(p + input_message_buffer->length + padlength,
+ token, sizeof(*token));
+
+ ret = krb5_encrypt(context, crypto,
+ usage, p,
+ input_message_buffer->length + padlength +
+ sizeof(*token),
+ &cipher);
+ if (ret != 0) {
+ *minor_status = ret;
+ krb5_crypto_destroy(context, crypto);
+ _gsskrb5_release_buffer(minor_status, output_message_buffer);
+ return GSS_S_FAILURE;
+ }
+ assert(sizeof(*token) + cipher.length == wrapped_len);
+ token->RRC[0] = (rrc >> 8) & 0xFF;
+ token->RRC[1] = (rrc >> 0) & 0xFF;
+
+ ret = rrc_rotate(cipher.data, cipher.length, rrc, FALSE);
+ if (ret != 0) {
+ *minor_status = ret;
+ krb5_crypto_destroy(context, crypto);
+ _gsskrb5_release_buffer(minor_status, output_message_buffer);
+ return GSS_S_FAILURE;
+ }
+ memcpy(p, cipher.data, cipher.length);
+ krb5_data_free(&cipher);
+ } else {
+ char *buf;
+ Checksum cksum;
+
+ buf = malloc(input_message_buffer->length + sizeof(*token));
+ if (buf == NULL) {
+ *minor_status = ENOMEM;
+ krb5_crypto_destroy(context, crypto);
+ _gsskrb5_release_buffer(minor_status, output_message_buffer);
+ return GSS_S_FAILURE;
+ }
+ memcpy(buf, input_message_buffer->value, input_message_buffer->length);
+ memcpy(buf + input_message_buffer->length, token, sizeof(*token));
+
+ ret = krb5_create_checksum(context, crypto,
+ usage, 0, buf,
+ input_message_buffer->length +
+ sizeof(*token),
+ &cksum);
+ if (ret != 0) {
+ *minor_status = ret;
+ krb5_crypto_destroy(context, crypto);
+ _gsskrb5_release_buffer(minor_status, output_message_buffer);
+ free(buf);
+ return GSS_S_FAILURE;
+ }
+
+ free(buf);
+
+ assert(cksum.checksum.length == cksumsize);
+ token->EC[0] = (cksum.checksum.length >> 8) & 0xFF;
+ token->EC[1] = (cksum.checksum.length >> 0) & 0xFF;
+ token->RRC[0] = (rrc >> 8) & 0xFF;
+ token->RRC[1] = (rrc >> 0) & 0xFF;
+
+ p += sizeof(*token);
+ memcpy(p, input_message_buffer->value, input_message_buffer->length);
+ memcpy(p + input_message_buffer->length,
+ cksum.checksum.data, cksum.checksum.length);
+
+ ret = rrc_rotate(p,
+ input_message_buffer->length + cksum.checksum.length, rrc, FALSE);
+ if (ret != 0) {
+ *minor_status = ret;
+ krb5_crypto_destroy(context, crypto);
+ _gsskrb5_release_buffer(minor_status, output_message_buffer);
+ free_Checksum(&cksum);
+ return GSS_S_FAILURE;
+ }
+ free_Checksum(&cksum);
+ }
+
+ krb5_crypto_destroy(context, crypto);
+
+ if (conf_state != NULL) {
+ *conf_state = conf_req_flag;
+ }
+
+ *minor_status = 0;
+ return GSS_S_COMPLETE;
+}
+
+OM_uint32 _gssapi_unwrap_cfx(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)
+{
+ krb5_crypto crypto;
+ gss_cfx_wrap_token token;
+ u_char token_flags;
+ krb5_error_code ret;
+ unsigned usage;
+ krb5_data data;
+ uint16_t ec, rrc;
+ OM_uint32 seq_number_lo, seq_number_hi;
+ size_t len;
+ u_char *p;
+
+ *minor_status = 0;
+
+ if (input_message_buffer->length < sizeof(*token)) {
+ return GSS_S_DEFECTIVE_TOKEN;
+ }
+
+ p = input_message_buffer->value;
+
+ token = (gss_cfx_wrap_token)p;
+
+ if (token->TOK_ID[0] != 0x05 || token->TOK_ID[1] != 0x04) {
+ return GSS_S_DEFECTIVE_TOKEN;
+ }
+
+ /* Ignore unknown flags */
+ token_flags = token->Flags &
+ (CFXSentByAcceptor | CFXSealed | CFXAcceptorSubkey);
+
+ if (token_flags & CFXSentByAcceptor) {
+ if ((context_handle->more_flags & LOCAL) == 0)
+ return GSS_S_DEFECTIVE_TOKEN;
+ }
+
+ if (context_handle->more_flags & ACCEPTOR_SUBKEY) {
+ if ((token_flags & CFXAcceptorSubkey) == 0)
+ return GSS_S_DEFECTIVE_TOKEN;
+ } else {
+ if (token_flags & CFXAcceptorSubkey)
+ return GSS_S_DEFECTIVE_TOKEN;
+ }
+
+ if (token->Filler != 0xFF) {
+ return GSS_S_DEFECTIVE_TOKEN;
+ }
+
+ if (conf_state != NULL) {
+ *conf_state = (token_flags & CFXSealed) ? 1 : 0;
+ }
+
+ ec = (token->EC[0] << 8) | token->EC[1];
+ rrc = (token->RRC[0] << 8) | token->RRC[1];
+
+ /*
+ * Check sequence number
+ */
+ _gsskrb5_decode_be_om_uint32(&token->SND_SEQ[0], &seq_number_hi);
+ _gsskrb5_decode_be_om_uint32(&token->SND_SEQ[4], &seq_number_lo);
+ if (seq_number_hi) {
+ /* no support for 64-bit sequence numbers */
+ *minor_status = ERANGE;
+ return GSS_S_UNSEQ_TOKEN;
+ }
+
+ HEIMDAL_MUTEX_lock(&context_handle->ctx_id_mutex);
+ ret = _gssapi_msg_order_check(context_handle->order, seq_number_lo);
+ if (ret != 0) {
+ *minor_status = 0;
+ HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex);
+ _gsskrb5_release_buffer(minor_status, output_message_buffer);
+ return ret;
+ }
+ HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex);
+
+ /*
+ * Decrypt and/or verify checksum
+ */
+ ret = krb5_crypto_init(context, key, 0, &crypto);
+ if (ret != 0) {
+ *minor_status = ret;
+ return GSS_S_FAILURE;
+ }
+
+ if (context_handle->more_flags & LOCAL) {
+ usage = KRB5_KU_USAGE_ACCEPTOR_SEAL;
+ } else {
+ usage = KRB5_KU_USAGE_INITIATOR_SEAL;
+ }
+
+ p += sizeof(*token);
+ len = input_message_buffer->length;
+ len -= (p - (u_char *)input_message_buffer->value);
+
+ /* Rotate by RRC; bogus to do this in-place XXX */
+ *minor_status = rrc_rotate(p, len, rrc, TRUE);
+ if (*minor_status != 0) {
+ krb5_crypto_destroy(context, crypto);
+ return GSS_S_FAILURE;
+ }
+
+ if (token_flags & CFXSealed) {
+ ret = krb5_decrypt(context, crypto, usage,
+ p, len, &data);
+ if (ret != 0) {
+ *minor_status = ret;
+ krb5_crypto_destroy(context, crypto);
+ return GSS_S_BAD_MIC;
+ }
+
+ /* Check that there is room for the pad and token header */
+ if (data.length < ec + sizeof(*token)) {
+ krb5_crypto_destroy(context, crypto);
+ krb5_data_free(&data);
+ return GSS_S_DEFECTIVE_TOKEN;
+ }
+ p = data.data;
+ p += data.length - sizeof(*token);
+
+ /* RRC is unprotected; don't modify input buffer */
+ ((gss_cfx_wrap_token)p)->RRC[0] = token->RRC[0];
+ ((gss_cfx_wrap_token)p)->RRC[1] = token->RRC[1];
+
+ /* Check the integrity of the header */
+ if (memcmp(p, token, sizeof(*token)) != 0) {
+ krb5_crypto_destroy(context, crypto);
+ krb5_data_free(&data);
+ return GSS_S_BAD_MIC;
+ }
+
+ output_message_buffer->value = data.data;
+ output_message_buffer->length = data.length - ec - sizeof(*token);
+ } else {
+ Checksum cksum;
+
+ /* Determine checksum type */
+ ret = krb5_crypto_get_checksum_type(context,
+ crypto, &cksum.cksumtype);
+ if (ret != 0) {
+ *minor_status = ret;
+ krb5_crypto_destroy(context, crypto);
+ return GSS_S_FAILURE;
+ }
+
+ cksum.checksum.length = ec;
+
+ /* Check we have at least as much data as the checksum */
+ if (len < cksum.checksum.length) {
+ *minor_status = ERANGE;
+ krb5_crypto_destroy(context, crypto);
+ return GSS_S_BAD_MIC;
+ }
+
+ /* Length now is of the plaintext only, no checksum */
+ len -= cksum.checksum.length;
+ cksum.checksum.data = p + len;
+
+ output_message_buffer->length = len; /* for later */
+ output_message_buffer->value = malloc(len + sizeof(*token));
+ if (output_message_buffer->value == NULL) {
+ *minor_status = ENOMEM;
+ krb5_crypto_destroy(context, crypto);
+ return GSS_S_FAILURE;
+ }
+
+ /* Checksum is over (plaintext-data | "header") */
+ memcpy(output_message_buffer->value, p, len);
+ memcpy((u_char *)output_message_buffer->value + len,
+ token, sizeof(*token));
+
+ /* EC is not included in checksum calculation */
+ token = (gss_cfx_wrap_token)((u_char *)output_message_buffer->value +
+ len);
+ token->EC[0] = 0;
+ token->EC[1] = 0;
+ token->RRC[0] = 0;
+ token->RRC[1] = 0;
+
+ ret = krb5_verify_checksum(context, crypto,
+ usage,
+ output_message_buffer->value,
+ len + sizeof(*token),
+ &cksum);
+ if (ret != 0) {
+ *minor_status = ret;
+ krb5_crypto_destroy(context, crypto);
+ _gsskrb5_release_buffer(minor_status, output_message_buffer);
+ return GSS_S_BAD_MIC;
+ }
+ }
+
+ krb5_crypto_destroy(context, crypto);
+
+ if (qop_state != NULL) {
+ *qop_state = GSS_C_QOP_DEFAULT;
+ }
+
+ *minor_status = 0;
+ return GSS_S_COMPLETE;
+}
+
+OM_uint32 _gssapi_mic_cfx(OM_uint32 *minor_status,
+ const gsskrb5_ctx context_handle,
+ krb5_context context,
+ gss_qop_t qop_req,
+ const gss_buffer_t message_buffer,
+ gss_buffer_t message_token,
+ krb5_keyblock *key)
+{
+ krb5_crypto crypto;
+ gss_cfx_mic_token token;
+ krb5_error_code ret;
+ unsigned usage;
+ Checksum cksum;
+ u_char *buf;
+ size_t len;
+ int32_t seq_number;
+
+ ret = krb5_crypto_init(context, key, 0, &crypto);
+ if (ret != 0) {
+ *minor_status = ret;
+ return GSS_S_FAILURE;
+ }
+
+ len = message_buffer->length + sizeof(*token);
+ buf = malloc(len);
+ if (buf == NULL) {
+ *minor_status = ENOMEM;
+ krb5_crypto_destroy(context, crypto);
+ return GSS_S_FAILURE;
+ }
+
+ memcpy(buf, message_buffer->value, message_buffer->length);
+
+ token = (gss_cfx_mic_token)(buf + message_buffer->length);
+ token->TOK_ID[0] = 0x04;
+ token->TOK_ID[1] = 0x04;
+ token->Flags = 0;
+ if ((context_handle->more_flags & LOCAL) == 0)
+ token->Flags |= CFXSentByAcceptor;
+ if (context_handle->more_flags & ACCEPTOR_SUBKEY)
+ token->Flags |= CFXAcceptorSubkey;
+ memset(token->Filler, 0xFF, 5);
+
+ HEIMDAL_MUTEX_lock(&context_handle->ctx_id_mutex);
+ krb5_auth_con_getlocalseqnumber(context,
+ context_handle->auth_context,
+ &seq_number);
+ _gsskrb5_encode_be_om_uint32(0, &token->SND_SEQ[0]);
+ _gsskrb5_encode_be_om_uint32(seq_number, &token->SND_SEQ[4]);
+ krb5_auth_con_setlocalseqnumber(context,
+ context_handle->auth_context,
+ ++seq_number);
+ HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex);
+
+ if (context_handle->more_flags & LOCAL) {
+ usage = KRB5_KU_USAGE_INITIATOR_SIGN;
+ } else {
+ usage = KRB5_KU_USAGE_ACCEPTOR_SIGN;
+ }
+
+ ret = krb5_create_checksum(context, crypto,
+ usage, 0, buf, len, &cksum);
+ if (ret != 0) {
+ *minor_status = ret;
+ krb5_crypto_destroy(context, crypto);
+ free(buf);
+ return GSS_S_FAILURE;
+ }
+ krb5_crypto_destroy(context, crypto);
+
+ /* Determine MIC length */
+ message_token->length = sizeof(*token) + cksum.checksum.length;
+ message_token->value = malloc(message_token->length);
+ if (message_token->value == NULL) {
+ *minor_status = ENOMEM;
+ free_Checksum(&cksum);
+ free(buf);
+ return GSS_S_FAILURE;
+ }
+
+ /* Token is { "header" | get_mic("header" | plaintext-data) } */
+ memcpy(message_token->value, token, sizeof(*token));
+ memcpy((u_char *)message_token->value + sizeof(*token),
+ cksum.checksum.data, cksum.checksum.length);
+
+ free_Checksum(&cksum);
+ free(buf);
+
+ *minor_status = 0;
+ return GSS_S_COMPLETE;
+}
+
+OM_uint32 _gssapi_verify_mic_cfx(OM_uint32 *minor_status,
+ const gsskrb5_ctx context_handle,
+ krb5_context context,
+ const gss_buffer_t message_buffer,
+ const gss_buffer_t token_buffer,
+ gss_qop_t *qop_state,
+ krb5_keyblock *key)
+{
+ krb5_crypto crypto;
+ gss_cfx_mic_token token;
+ u_char token_flags;
+ krb5_error_code ret;
+ unsigned usage;
+ OM_uint32 seq_number_lo, seq_number_hi;
+ u_char *buf, *p;
+ Checksum cksum;
+
+ *minor_status = 0;
+
+ if (token_buffer->length < sizeof(*token)) {
+ return GSS_S_DEFECTIVE_TOKEN;
+ }
+
+ p = token_buffer->value;
+
+ token = (gss_cfx_mic_token)p;
+
+ if (token->TOK_ID[0] != 0x04 || token->TOK_ID[1] != 0x04) {
+ return GSS_S_DEFECTIVE_TOKEN;
+ }
+
+ /* Ignore unknown flags */
+ token_flags = token->Flags & (CFXSentByAcceptor | CFXAcceptorSubkey);
+
+ if (token_flags & CFXSentByAcceptor) {
+ if ((context_handle->more_flags & LOCAL) == 0)
+ return GSS_S_DEFECTIVE_TOKEN;
+ }
+ if (context_handle->more_flags & ACCEPTOR_SUBKEY) {
+ if ((token_flags & CFXAcceptorSubkey) == 0)
+ return GSS_S_DEFECTIVE_TOKEN;
+ } else {
+ if (token_flags & CFXAcceptorSubkey)
+ return GSS_S_DEFECTIVE_TOKEN;
+ }
+
+ if (memcmp(token->Filler, "\xff\xff\xff\xff\xff", 5) != 0) {
+ return GSS_S_DEFECTIVE_TOKEN;
+ }
+
+ /*
+ * Check sequence number
+ */
+ _gsskrb5_decode_be_om_uint32(&token->SND_SEQ[0], &seq_number_hi);
+ _gsskrb5_decode_be_om_uint32(&token->SND_SEQ[4], &seq_number_lo);
+ if (seq_number_hi) {
+ *minor_status = ERANGE;
+ return GSS_S_UNSEQ_TOKEN;
+ }
+
+ HEIMDAL_MUTEX_lock(&context_handle->ctx_id_mutex);
+ ret = _gssapi_msg_order_check(context_handle->order, seq_number_lo);
+ if (ret != 0) {
+ *minor_status = 0;
+ HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex);
+ return ret;
+ }
+ HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex);
+
+ /*
+ * Verify checksum
+ */
+ ret = krb5_crypto_init(context, key, 0, &crypto);
+ if (ret != 0) {
+ *minor_status = ret;
+ return GSS_S_FAILURE;
+ }
+
+ ret = krb5_crypto_get_checksum_type(context, crypto,
+ &cksum.cksumtype);
+ if (ret != 0) {
+ *minor_status = ret;
+ krb5_crypto_destroy(context, crypto);
+ return GSS_S_FAILURE;
+ }
+
+ cksum.checksum.data = p + sizeof(*token);
+ cksum.checksum.length = token_buffer->length - sizeof(*token);
+
+ if (context_handle->more_flags & LOCAL) {
+ usage = KRB5_KU_USAGE_ACCEPTOR_SIGN;
+ } else {
+ usage = KRB5_KU_USAGE_INITIATOR_SIGN;
+ }
+
+ buf = malloc(message_buffer->length + sizeof(*token));
+ if (buf == NULL) {
+ *minor_status = ENOMEM;
+ krb5_crypto_destroy(context, crypto);
+ return GSS_S_FAILURE;
+ }
+ memcpy(buf, message_buffer->value, message_buffer->length);
+ memcpy(buf + message_buffer->length, token, sizeof(*token));
+
+ ret = krb5_verify_checksum(context, crypto,
+ usage,
+ buf,
+ sizeof(*token) + message_buffer->length,
+ &cksum);
+ krb5_crypto_destroy(context, crypto);
+ if (ret != 0) {
+ *minor_status = ret;
+ free(buf);
+ return GSS_S_BAD_MIC;
+ }
+
+ free(buf);
+
+ if (qop_state != NULL) {
+ *qop_state = GSS_C_QOP_DEFAULT;
+ }
+
+ return GSS_S_COMPLETE;
+}
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