1 files changed, 963 insertions, 0 deletions

diff --git a/third_party/heimdal/lib/krb5/fast.c b/third_party/heimdal/lib/krb5/fast.c
new file mode 100644
index 0000000..90133a7
--- /dev/null
+++ b/third_party/heimdal/lib/krb5/fast.c
@@ -0,0 +1,963 @@
+/*
+ * Copyright (c) 2011 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 "krb5_locl.h"
+#ifndef WIN32
+#include <heim-ipc.h>
+#endif
+
+KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
+_krb5_fast_cf2(krb5_context context,
+	       krb5_keyblock *key1,
+	       const char *pepper1,
+	       krb5_keyblock *key2,
+	       const char *pepper2,
+	       krb5_keyblock *armorkey,
+	       krb5_crypto *armor_crypto)
+{
+    krb5_crypto crypto1, crypto2;
+    krb5_data pa1, pa2;
+    krb5_error_code ret;
+
+    ret = krb5_crypto_init(context, key1, 0, &crypto1);
+    if (ret)
+	return ret;
+
+    ret = krb5_crypto_init(context, key2, 0, &crypto2);
+    if (ret) {
+	krb5_crypto_destroy(context, crypto1);
+	return ret;
+    }
+
+    pa1.data = rk_UNCONST(pepper1);
+    pa1.length = strlen(pepper1);
+    pa2.data = rk_UNCONST(pepper2);
+    pa2.length = strlen(pepper2);
+
+    ret = krb5_crypto_fx_cf2(context, crypto1, crypto2, &pa1, &pa2,
+			     key1->keytype, armorkey);
+    krb5_crypto_destroy(context, crypto1);
+    krb5_crypto_destroy(context, crypto2);
+    if (ret)
+	return ret;
+
+    if (armor_crypto) {
+	ret = krb5_crypto_init(context, armorkey, 0, armor_crypto);
+	if (ret)
+	    krb5_free_keyblock_contents(context, armorkey);
+    }
+
+    return ret;
+}
+
+KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
+_krb5_fast_armor_key(krb5_context context,
+		     krb5_keyblock *subkey,
+		     krb5_keyblock *sessionkey,
+		     krb5_keyblock *armorkey,
+		     krb5_crypto *armor_crypto)
+{
+    return _krb5_fast_cf2(context,
+			  subkey,
+			  "subkeyarmor",
+			  sessionkey,
+			  "ticketarmor",
+			  armorkey,
+			  armor_crypto);
+}
+
+KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
+_krb5_fast_explicit_armor_key(krb5_context context,
+			      krb5_keyblock *armorkey,
+			      krb5_keyblock *subkey,
+			      krb5_keyblock *explicit_armorkey,
+			      krb5_crypto *explicit_armor_crypto)
+{
+    return _krb5_fast_cf2(context,
+			  armorkey,
+			  "explicitarmor",
+			  subkey,
+			  "tgsarmor",
+			  explicit_armorkey,
+			  explicit_armor_crypto);
+}
+
+static krb5_error_code
+check_fast(krb5_context context, struct krb5_fast_state *state)
+{
+    if (state && (state->flags & KRB5_FAST_EXPECTED)) {
+	krb5_set_error_message(context, KRB5KRB_AP_ERR_MODIFIED,
+			       "Expected FAST, but no FAST "
+			       "was in the response from the KDC");
+	return KRB5KRB_AP_ERR_MODIFIED;
+    }
+    return 0;
+}
+
+static krb5_error_code
+make_local_fast_ap_fxarmor(krb5_context context,
+			   krb5_ccache armor_ccache,
+			   krb5_const_realm realm,
+			   krb5_data *armor_value,
+			   krb5_keyblock *armor_key,
+			   krb5_crypto *armor_crypto)
+{
+    krb5_auth_context auth_context = NULL;
+    krb5_creds cred, *credp = NULL;
+    krb5_error_code ret;
+    krb5_data empty;
+    krb5_const_realm tgs_realm;
+
+    if (armor_ccache == NULL) {
+	krb5_set_error_message(context, EINVAL,
+			       "Armor credential cache required");
+	return EINVAL;
+    }
+
+    krb5_data_zero(&empty);
+    memset(&cred, 0, sizeof(cred));
+
+    ret = krb5_auth_con_init (context, &auth_context);
+    if (ret)
+	goto out;
+
+    ret = krb5_cc_get_principal(context, armor_ccache, &cred.client);
+    if (ret)
+	goto out;
+
+    /*
+     * Make sure we don't ask for a krbtgt/WELLKNOWN:ANONYMOUS
+     */
+    if (krb5_principal_is_anonymous(context, cred.client,
+				    KRB5_ANON_MATCH_UNAUTHENTICATED))
+	tgs_realm = realm;
+    else
+	tgs_realm = cred.client->realm;
+
+    ret = krb5_make_principal(context, &cred.server,
+			      tgs_realm,
+			      KRB5_TGS_NAME,
+			      tgs_realm,
+			      NULL);
+    if (ret)
+	goto out;
+
+    ret = krb5_get_credentials(context, 0, armor_ccache, &cred, &credp);
+    if (ret)
+	goto out;
+
+    ret = krb5_auth_con_add_AuthorizationData(context, auth_context,
+					      KRB5_AUTHDATA_FX_FAST_ARMOR,
+					      &empty);
+    if (ret)
+	goto out;
+
+    ret = krb5_mk_req_extended(context,
+			       &auth_context,
+			       AP_OPTS_USE_SUBKEY,
+			       NULL,
+			       credp,
+			       armor_value);
+    if (ret)
+	goto out;
+
+    ret = _krb5_fast_armor_key(context,
+			       auth_context->local_subkey,
+			       auth_context->keyblock,
+			       armor_key,
+			       armor_crypto);
+    if (ret)
+	goto out;
+
+ out:
+    if (auth_context)
+	krb5_auth_con_free(context, auth_context);
+    if (credp)
+	krb5_free_creds(context, credp);
+    krb5_free_principal(context, cred.server);
+    krb5_free_principal(context, cred.client);
+
+    return ret;
+}
+
+#ifndef WIN32
+static heim_base_once_t armor_service_once = HEIM_BASE_ONCE_INIT;
+static heim_ipc armor_service = NULL;
+
+static void
+fast_armor_init_ipc(void *ctx)
+{
+    heim_ipc *ipc = ctx;
+    heim_ipc_init_context("ANY:org.h5l.armor-service", ipc);
+}
+#endif
+
+static krb5_error_code
+make_fast_ap_fxarmor(krb5_context context,
+		     struct krb5_fast_state *state,
+		     krb5_const_realm realm,
+		     KrbFastArmor **armor)
+{
+    KrbFastArmor *fxarmor = NULL;
+    krb5_error_code ret;
+
+    *armor = NULL;
+
+    ALLOC(fxarmor, 1);
+    if (fxarmor == NULL) {
+	ret = ENOMEM;
+	goto out;
+    }
+
+    if (state->flags & KRB5_FAST_AP_ARMOR_SERVICE) {
+#ifdef WIN32
+	krb5_set_error_message(context, ENOTSUP, "Fast armor IPC service not supportted yet on Windows");
+	ret = ENOTSUP;
+	goto out;
+#else
+	KERB_ARMOR_SERVICE_REPLY msg;
+	krb5_data request, reply;
+
+	heim_base_once_f(&armor_service_once, &armor_service, fast_armor_init_ipc);
+	if (armor_service == NULL) {
+	    krb5_set_error_message(context, ENOENT, "Failed to open fast armor service");
+	    ret = ENOENT;
+	    goto out;
+	}
+
+	krb5_data_zero(&reply);
+
+	request.data = rk_UNCONST(realm);
+	request.length = strlen(realm);
+
+	ret = heim_ipc_call(armor_service, &request, &reply, NULL);
+	if (ret) {
+	    krb5_set_error_message(context, ret, "Failed to get armor service credential");
+	    goto out;
+	}
+
+	ret = decode_KERB_ARMOR_SERVICE_REPLY(reply.data, reply.length, &msg, NULL);
+	krb5_data_free(&reply);
+	if (ret)
+	    goto out;
+
+	ret = copy_KrbFastArmor(fxarmor, &msg.armor);
+	if (ret) {
+	    free_KERB_ARMOR_SERVICE_REPLY(&msg);
+	    goto out;
+	}
+
+	ret = krb5_copy_keyblock_contents(context, &msg.armor_key, &state->armor_key);
+	free_KERB_ARMOR_SERVICE_REPLY(&msg);
+	if (ret)
+	    goto out;
+
+	ret = krb5_crypto_init(context, &state->armor_key, 0, &state->armor_crypto);
+	if (ret)
+	    goto out;
+#endif /* WIN32 */
+    } else {
+	fxarmor->armor_type = 1;
+
+	ret = make_local_fast_ap_fxarmor(context,
+					 state->armor_ccache,
+					 realm,
+					 &fxarmor->armor_value,
+					 &state->armor_key,
+					 &state->armor_crypto);
+	if (ret)
+	    goto out;
+    }
+
+
+    *armor = fxarmor;
+    fxarmor = NULL;
+
+ out:
+    if (fxarmor) {
+	free_KrbFastArmor(fxarmor);
+	free(fxarmor);
+    }
+    return ret;
+}
+
+static krb5_error_code
+unwrap_fast_rep(krb5_context context,
+		struct krb5_fast_state *state,
+		PA_DATA *pa,
+		KrbFastResponse *fastrep)
+{
+    PA_FX_FAST_REPLY fxfastrep;
+    krb5_error_code ret;
+
+    memset(&fxfastrep, 0, sizeof(fxfastrep));
+
+    ret = decode_PA_FX_FAST_REPLY(pa->padata_value.data,
+				  pa->padata_value.length,
+				  &fxfastrep, NULL);
+    if (ret)
+	return ret;
+
+    if (fxfastrep.element == choice_PA_FX_FAST_REPLY_armored_data) {
+	krb5_data data;
+
+	ret = krb5_decrypt_EncryptedData(context,
+					 state->armor_crypto,
+					 KRB5_KU_FAST_REP,
+					 &fxfastrep.u.armored_data.enc_fast_rep,
+					 &data);
+	if (ret)
+	    goto out;
+
+	ret = decode_KrbFastResponse(data.data, data.length, fastrep, NULL);
+	krb5_data_free(&data);
+	if (ret)
+	    goto out;
+
+    } else {
+	ret = KRB5KDC_ERR_PREAUTH_FAILED;
+	goto out;
+    }
+
+ out:
+    free_PA_FX_FAST_REPLY(&fxfastrep);
+
+    return ret;
+}
+
+static krb5_error_code
+set_anon_principal(krb5_context context, PrincipalName **p)
+{
+
+    ALLOC((*p), 1);
+    if (*p == NULL)
+	goto fail;
+
+    (*p)->name_type = KRB5_NT_PRINCIPAL;
+
+    ALLOC_SEQ(&(*p)->name_string, 2);
+    if ((*p)->name_string.val == NULL)
+	goto fail;
+
+    (*p)->name_string.val[0] = strdup(KRB5_WELLKNOWN_NAME);
+    if ((*p)->name_string.val[0] == NULL)
+	goto fail;
+
+    (*p)->name_string.val[1] = strdup(KRB5_ANON_NAME);
+    if ((*p)->name_string.val[1] == NULL)
+	goto fail;
+
+    return 0;
+ fail:
+    if (*p) {
+	if ((*p)->name_string.val) {
+	    free((*p)->name_string.val[0]);
+	    free((*p)->name_string.val[1]);
+	    free((*p)->name_string.val);
+	}
+	free(*p);
+    }
+
+    return krb5_enomem(context);
+}
+
+krb5_error_code
+_krb5_fast_create_armor(krb5_context context,
+			struct krb5_fast_state *state,
+			const char *realm)
+{
+    krb5_error_code ret;
+
+    if (state->armor_crypto == NULL) {
+	if (state->armor_ccache || state->armor_ac || (state->flags & KRB5_FAST_AP_ARMOR_SERVICE)) {
+	    /*
+	     * Instead of keeping state in FX_COOKIE in the KDC, we
+	     * rebuild a new armor key for every request, because this
+	     * is what the MIT KDC expect and RFC6113 is vage about
+	     * what the behavior should be.
+	     */
+	    state->type = choice_PA_FX_FAST_REQUEST_armored_data;
+	} else {
+	    return check_fast(context, state);
+	}
+    }
+
+    if (state->type == choice_PA_FX_FAST_REQUEST_armored_data) {
+	if (state->armor_crypto) {
+	    krb5_crypto_destroy(context, state->armor_crypto);
+	    state->armor_crypto = NULL;
+	}
+	if (state->strengthen_key) {
+	    krb5_free_keyblock(context, state->strengthen_key);
+	    state->strengthen_key = NULL;
+	}
+	krb5_free_keyblock_contents(context, &state->armor_key);
+
+	/*
+	 * If we have a armor auth context, its because the caller
+	 * wants us to do an implicit FAST armor (TGS-REQ).
+	 */
+	if (state->armor_ac) {
+	    heim_assert((state->flags & KRB5_FAST_AS_REQ) == 0, "FAST AS with AC");
+
+	    ret = _krb5_fast_armor_key(context,
+				       state->armor_ac->local_subkey,
+				       state->armor_ac->keyblock,
+				       &state->armor_key,
+				       &state->armor_crypto);
+	    if (ret)
+		goto out;
+	} else {
+	    heim_assert((state->flags & KRB5_FAST_AS_REQ) != 0, "FAST TGS without AC");
+
+	    if (state->armor_data) {
+		free_KrbFastArmor(state->armor_data);
+		free(state->armor_data);
+                state->armor_data = NULL;
+	    }
+	    ret = make_fast_ap_fxarmor(context, state, realm,
+				       &state->armor_data);
+	    if (ret)
+		goto out;
+	}
+    } else {
+	heim_abort("unknown state type: %d", (int)state->type);
+    }
+ out:
+    return ret;
+}
+
+
+krb5_error_code
+_krb5_fast_wrap_req(krb5_context context,
+		    struct krb5_fast_state *state,
+		    KDC_REQ *req)
+{
+    PA_FX_FAST_REQUEST fxreq;
+    krb5_error_code ret;
+    KrbFastReq fastreq;
+    krb5_data data, aschecksum_data, tgschecksum_data;
+    const krb5_data *checksum_data = NULL;
+    size_t size = 0;
+    krb5_boolean readd_padata_to_outer = FALSE;
+
+    if (state->flags & KRB5_FAST_DISABLED) {
+	_krb5_debug(context, 10, "fast disabled, not doing any fast wrapping");
+	return 0;
+    }
+
+    memset(&fxreq, 0, sizeof(fxreq));
+    memset(&fastreq, 0, sizeof(fastreq));
+    krb5_data_zero(&data);
+    krb5_data_zero(&aschecksum_data);
+    krb5_data_zero(&tgschecksum_data);
+
+    if (state->armor_crypto == NULL)
+	return check_fast(context, state);
+
+    state->flags |= KRB5_FAST_EXPECTED;
+
+    fastreq.fast_options.hide_client_names = 1;
+
+    ret = copy_KDC_REQ_BODY(&req->req_body, &fastreq.req_body);
+    if (ret)
+	goto out;
+
+    /*
+     * In the case of a AS-REQ, remove all account names. Want to this
+     * for TGS-REQ too, but due to layering this is tricky.
+     *
+     * 1. TGS-REQ need checksum of REQ-BODY
+     * 2. FAST needs checksum of TGS-REQ, so, FAST needs to happen after TGS-REQ
+     * 3. FAST privacy mangaling needs to happen before TGS-REQ does the checksum in 1.
+     *
+     * So lets not modify the bits for now for TGS-REQ
+     */
+    if (state->flags & KRB5_FAST_AS_REQ) {
+	free_KDC_REQ_BODY(&req->req_body);
+
+	req->req_body.realm = strdup(KRB5_ANON_REALM);
+	if (req->req_body.realm == NULL) {
+	    ret = krb5_enomem(context);
+	    goto out;
+	}
+
+	ret = set_anon_principal(context, &req->req_body.cname);
+	if (ret)
+	    goto out;
+
+	ALLOC(req->req_body.till, 1);
+	*req->req_body.till = 0;
+
+	ASN1_MALLOC_ENCODE(KDC_REQ_BODY,
+			   aschecksum_data.data,
+			   aschecksum_data.length,
+			   &req->req_body,
+			   &size, ret);
+	if (ret)
+	    goto out;
+	heim_assert(aschecksum_data.length == size, "ASN.1 internal error");
+
+	checksum_data = &aschecksum_data;
+
+	if (req->padata) {
+	    ret = copy_METHOD_DATA(req->padata, &fastreq.padata);
+	    free_METHOD_DATA(req->padata);
+	    if (ret)
+		goto out;
+	}
+    } else {
+	const PA_DATA *tgs_req_ptr = NULL;
+	int tgs_req_idx = 0;
+	size_t i;
+
+	heim_assert(req->padata != NULL, "req->padata is NULL");
+
+	tgs_req_ptr = krb5_find_padata(req->padata->val,
+				       req->padata->len,
+				       KRB5_PADATA_TGS_REQ,
+				       &tgs_req_idx);
+	heim_assert(tgs_req_ptr != NULL, "KRB5_PADATA_TGS_REQ not found");
+	heim_assert(tgs_req_idx == 0, "KRB5_PADATA_TGS_REQ not first");
+
+	tgschecksum_data.data = tgs_req_ptr->padata_value.data;
+	tgschecksum_data.length = tgs_req_ptr->padata_value.length;
+	checksum_data = &tgschecksum_data;
+
+	/*
+	 * Now copy all remaining once to
+	 * the fastreq.padata and clear
+	 * them in the outer req first,
+	 * and remember to readd them later.
+	 */
+	readd_padata_to_outer = TRUE;
+
+	for (i = 1; i < req->padata->len; i++) {
+	    PA_DATA *val = &req->padata->val[i];
+
+	    ret = krb5_padata_add(context,
+				  &fastreq.padata,
+				  val->padata_type,
+				  val->padata_value.data,
+				  val->padata_value.length);
+	    if (ret) {
+		krb5_set_error_message(context, ret,
+				       N_("malloc: out of memory", ""));
+		goto out;
+	    }
+	    val->padata_value.data = NULL;
+	    val->padata_value.length = 0;
+	}
+
+	/*
+	 * Only TGS-REQ remaining
+	 */
+	req->padata->len = 1;
+    }
+
+    if (req->padata == NULL) {
+	ALLOC(req->padata, 1);
+	if (req->padata == NULL) {
+	    ret = krb5_enomem(context);
+	    goto out;
+	}
+    }
+
+    ASN1_MALLOC_ENCODE(KrbFastReq, data.data, data.length, &fastreq, &size, ret);
+    if (ret)
+	goto out;
+    heim_assert(data.length == size, "ASN.1 internal error");
+
+    fxreq.element = state->type;
+
+    if (state->type == choice_PA_FX_FAST_REQUEST_armored_data) {
+	fxreq.u.armored_data.armor = state->armor_data;
+	state->armor_data = NULL;
+
+	heim_assert(state->armor_crypto != NULL,
+		    "FAST armor key missing when FAST started");
+
+	ret = krb5_create_checksum(context, state->armor_crypto,
+				   KRB5_KU_FAST_REQ_CHKSUM, 0,
+				   checksum_data->data,
+				   checksum_data->length,
+				   &fxreq.u.armored_data.req_checksum);
+	if (ret)
+	    goto out;
+
+	ret = krb5_encrypt_EncryptedData(context, state->armor_crypto,
+					 KRB5_KU_FAST_ENC,
+					 data.data,
+					 data.length,
+					 0,
+					 &fxreq.u.armored_data.enc_fast_req);
+	krb5_data_free(&data);
+	if (ret)
+	    goto out;
+
+    } else {
+	krb5_data_free(&data);
+	heim_assert(false, "unknown FAST type, internal error");
+    }
+
+    ASN1_MALLOC_ENCODE(PA_FX_FAST_REQUEST, data.data, data.length, &fxreq, &size, ret);
+    if (ret)
+	goto out;
+    heim_assert(data.length == size, "ASN.1 internal error");
+
+
+    ret = krb5_padata_add(context, req->padata, KRB5_PADATA_FX_FAST, data.data, data.length);
+    if (ret)
+	goto out;
+    krb5_data_zero(&data);
+
+    if (readd_padata_to_outer) {
+	size_t i;
+
+	for (i = 0; i < fastreq.padata.len; i++) {
+	    PA_DATA *val = &fastreq.padata.val[i];
+
+	    ret = krb5_padata_add(context,
+				  req->padata,
+				  val->padata_type,
+				  val->padata_value.data,
+				  val->padata_value.length);
+	    if (ret) {
+		krb5_set_error_message(context, ret,
+				       N_("malloc: out of memory", ""));
+		goto out;
+	    }
+	    val->padata_value.data = NULL;
+	    val->padata_value.length = 0;
+	}
+    }
+
+ out:
+    free_KrbFastReq(&fastreq);
+    free_PA_FX_FAST_REQUEST(&fxreq);
+    krb5_data_free(&data);
+    krb5_data_free(&aschecksum_data);
+
+    return ret;
+}
+
+krb5_error_code
+_krb5_fast_unwrap_error(krb5_context context,
+			int32_t nonce,
+			struct krb5_fast_state *state,
+			METHOD_DATA *md,
+			KRB_ERROR *error)
+{
+    KrbFastResponse fastrep;
+    krb5_error_code ret;
+    PA_DATA *pa;
+    int idx;
+
+    if (state->armor_crypto == NULL)
+	return check_fast(context, state);
+
+    memset(&fastrep, 0, sizeof(fastrep));
+
+    idx = 0;
+    pa = krb5_find_padata(md->val, md->len, KRB5_PADATA_FX_FAST, &idx);
+    if (pa == NULL) {
+	ret = KRB5_KDCREP_MODIFIED;
+	krb5_set_error_message(context, ret,
+			       N_("FAST fast response is missing FX-FAST", ""));
+	goto out;
+    }
+
+    ret = unwrap_fast_rep(context, state, pa, &fastrep);
+    if (ret)
+	goto out;
+
+    if (fastrep.strengthen_key || nonce != (int32_t)fastrep.nonce) {
+	ret = KRB5KDC_ERR_PREAUTH_FAILED;
+	goto out;
+    }
+
+    idx = 0;
+    pa = krb5_find_padata(fastrep.padata.val, fastrep.padata.len, KRB5_PADATA_FX_ERROR, &idx);
+    if (pa == NULL) {
+	ret = KRB5_KDCREP_MODIFIED;
+	krb5_set_error_message(context, ret, N_("No wrapped error", ""));
+	goto out;
+    }
+
+    free_KRB_ERROR(error);
+
+    ret = krb5_rd_error(context, &pa->padata_value, error);
+    if (ret)
+	goto out;
+
+    if (error->e_data)
+	_krb5_debug(context, 10, "FAST wrapped KBB_ERROR contained e_data: %d",
+		     (int)error->e_data->length);
+
+    free_METHOD_DATA(md);
+    md->val = fastrep.padata.val;
+    md->len = fastrep.padata.len;
+
+    fastrep.padata.val = NULL;
+    fastrep.padata.len = 0;
+
+ out:
+    free_KrbFastResponse(&fastrep);
+    return ret;
+}
+
+krb5_error_code
+_krb5_fast_unwrap_kdc_rep(krb5_context context, int32_t nonce,
+			  krb5_data *chksumdata,
+			  struct krb5_fast_state *state, AS_REP *rep)
+{
+    KrbFastResponse fastrep;
+    krb5_error_code ret;
+    PA_DATA *pa = NULL;
+    int idx = 0;
+
+    if (state == NULL || state->armor_crypto == NULL || rep->padata == NULL)
+	return check_fast(context, state);
+
+    /* find PA_FX_FAST_REPLY */
+
+    pa = krb5_find_padata(rep->padata->val, rep->padata->len,
+			  KRB5_PADATA_FX_FAST, &idx);
+    if (pa == NULL)
+	return check_fast(context, state);
+
+    memset(&fastrep, 0, sizeof(fastrep));
+
+    ret = unwrap_fast_rep(context, state, pa, &fastrep);
+    if (ret)
+	goto out;
+
+    free_METHOD_DATA(rep->padata);
+    ret = copy_METHOD_DATA(&fastrep.padata, rep->padata);
+    if (ret)
+	goto out;
+
+    if (fastrep.strengthen_key) {
+	if (state->strengthen_key)
+	    krb5_free_keyblock(context, state->strengthen_key);
+
+	ret = krb5_copy_keyblock(context, fastrep.strengthen_key, &state->strengthen_key);
+	if (ret)
+	    goto out;
+    }
+
+    if (nonce != (int32_t)fastrep.nonce) {
+	ret = KRB5KDC_ERR_PREAUTH_FAILED;
+	goto out;
+    }
+    if (fastrep.finished) {
+	PrincipalName cname;
+	krb5_realm crealm = NULL;
+
+	if (chksumdata == NULL) {
+	    ret = KRB5KDC_ERR_PREAUTH_FAILED;
+	    goto out;
+	}
+
+	ret = krb5_verify_checksum(context, state->armor_crypto,
+				   KRB5_KU_FAST_FINISHED,
+				   chksumdata->data, chksumdata->length,
+				   &fastrep.finished->ticket_checksum);
+	if (ret)
+	    goto out;
+
+	/* update */
+	ret = copy_Realm(&fastrep.finished->crealm, &crealm);
+	if (ret)
+	    goto out;
+	free_Realm(&rep->crealm);
+	rep->crealm = crealm;
+
+	ret = copy_PrincipalName(&fastrep.finished->cname, &cname);
+	if (ret)
+	    goto out;
+	free_PrincipalName(&rep->cname);
+	rep->cname = cname;
+    } else if (chksumdata) {
+	/* expected fastrep.finish but didn't get it */
+	ret = KRB5KDC_ERR_PREAUTH_FAILED;
+    }
+
+ out:
+    free_KrbFastResponse(&fastrep);
+    return ret;
+}
+
+void
+_krb5_fast_free(krb5_context context, struct krb5_fast_state *state)
+{
+    if (state->armor_ccache) {
+	if (state->flags & KRB5_FAST_ANON_PKINIT_ARMOR)
+	    krb5_cc_destroy(context, state->armor_ccache);
+	else
+	    krb5_cc_close(context, state->armor_ccache);
+    }
+    if (state->armor_service)
+	krb5_free_principal(context, state->armor_service);
+    if (state->armor_crypto)
+	krb5_crypto_destroy(context, state->armor_crypto);
+    if (state->strengthen_key)
+	krb5_free_keyblock(context, state->strengthen_key);
+    krb5_free_keyblock_contents(context, &state->armor_key);
+    if (state->armor_data) {
+	free_KrbFastArmor(state->armor_data);
+	free(state->armor_data);
+    }
+
+    if (state->anon_pkinit_ctx)
+	krb5_init_creds_free(context, state->anon_pkinit_ctx);
+    if (state->anon_pkinit_opt)
+	krb5_get_init_creds_opt_free(context, state->anon_pkinit_opt);
+
+    memset(state, 0, sizeof(*state));
+}
+
+krb5_error_code
+_krb5_fast_anon_pkinit_step(krb5_context context,
+			    krb5_init_creds_context ctx,
+			    struct krb5_fast_state *state,
+			    const krb5_data *in,
+			    krb5_data *out,
+			    krb5_realm *out_realm,
+			    unsigned int *flags)
+{
+    krb5_error_code ret;
+    krb5_const_realm realm = _krb5_init_creds_get_cred_client(context, ctx)->realm;
+    krb5_init_creds_context anon_pk_ctx;
+    krb5_principal principal = NULL, anon_pk_client;
+    krb5_ccache ccache = NULL;
+    krb5_creds cred;
+    krb5_data data = { 3, rk_UNCONST("yes") };
+
+    krb5_data_zero(out);
+    *out_realm = NULL;
+
+    memset(&cred, 0, sizeof(cred));
+
+    if (state->anon_pkinit_opt == NULL) {
+	ret = krb5_get_init_creds_opt_alloc(context, &state->anon_pkinit_opt);
+	if (ret)
+	    goto out;
+
+	krb5_get_init_creds_opt_set_tkt_life(state->anon_pkinit_opt, 60);
+	krb5_get_init_creds_opt_set_anonymous(state->anon_pkinit_opt, TRUE);
+
+	ret = krb5_make_principal(context, &principal, realm,
+				  KRB5_WELLKNOWN_NAME, KRB5_ANON_NAME, NULL);
+	if (ret)
+	    goto out;
+
+	ret = krb5_get_init_creds_opt_set_pkinit(context,
+						 state->anon_pkinit_opt,
+						 principal,
+						 NULL, NULL, NULL, NULL,
+						 KRB5_GIC_OPT_PKINIT_ANONYMOUS |
+						 KRB5_GIC_OPT_PKINIT_NO_KDC_ANCHOR,
+						 NULL, NULL, NULL);
+	if (ret)
+	    goto out;
+
+	ret = krb5_init_creds_init(context, principal, NULL, NULL,
+				   _krb5_init_creds_get_cred_starttime(context, ctx),
+				   state->anon_pkinit_opt,
+				   &state->anon_pkinit_ctx);
+	if (ret)
+	    goto out;
+    }
+
+    anon_pk_ctx = state->anon_pkinit_ctx;
+
+    ret = krb5_init_creds_step(context, anon_pk_ctx, in, out, out_realm, flags);
+    if (ret ||
+	(*flags & KRB5_INIT_CREDS_STEP_FLAG_CONTINUE))
+	goto out;
+
+    ret = krb5_process_last_request(context, state->anon_pkinit_opt, anon_pk_ctx);
+    if (ret)
+	goto out;
+
+    ret = krb5_cc_new_unique(context, "MEMORY", NULL, &ccache);
+    if (ret)
+	goto out;
+
+    ret = krb5_init_creds_get_creds(context, anon_pk_ctx, &cred);
+    if (ret)
+	goto out;
+
+    if (!cred.flags.b.enc_pa_rep) {
+	ret = KRB5KDC_ERR_BADOPTION; /* KDC does not support FAST */
+	goto out;
+    }
+
+    anon_pk_client = _krb5_init_creds_get_cred_client(context, anon_pk_ctx);
+
+    ret = krb5_cc_initialize(context, ccache, anon_pk_client);
+    if (ret)
+	goto out;
+
+    ret = krb5_cc_store_cred(context, ccache, &cred);
+    if (ret)
+	goto out;
+
+    ret = krb5_cc_set_config(context, ccache, cred.server,
+			     "fast_avail", &data);
+    if (ret && ret != KRB5_CC_NOSUPP)
+	return ret;
+
+    if (_krb5_pk_is_kdc_verified(context, state->anon_pkinit_opt))
+	state->flags |= KRB5_FAST_KDC_VERIFIED;
+    else
+	state->flags &= ~(KRB5_FAST_KDC_VERIFIED);
+
+    state->armor_ccache = ccache;
+    ccache = NULL;
+
+    krb5_init_creds_free(context, state->anon_pkinit_ctx);
+    state->anon_pkinit_ctx = NULL;
+
+    krb5_get_init_creds_opt_free(context, state->anon_pkinit_opt);
+    state->anon_pkinit_opt = NULL;
+
+out:
+    krb5_free_principal(context, principal);
+    krb5_free_cred_contents(context, &cred);
+    if (ccache)
+	krb5_cc_destroy(context, ccache);
+
+    return ret;
+}