+++ /dev/null
-/*
- Unix SMB/CIFS implementation.
-
- endpoint server for the backupkey interface
-
- Copyright (C) Matthieu Patou <mat@samba.org> 2010
-
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 3 of the License, or
- (at your option) any later version.
-
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with this program. If not, see <http://www.gnu.org/licenses/>.
-*/
-
-#include "includes.h"
-#include "rpc_server/dcerpc_server.h"
-#include "rpc_server/common/common.h"
-#include "librpc/gen_ndr/ndr_backupkey.h"
-#include "dsdb/common/util.h"
-#include "dsdb/samdb/samdb.h"
-#include "lib/ldb/include/ldb_errors.h"
-#include "../lib/util/util_ldb.h"
-#include "param/param.h"
-#include "auth/session.h"
-#include "system/network.h"
-#include <com_err.h>
-#include <hx509.h>
-#include <hcrypto/rsa.h>
-#include <hcrypto/bn.h>
-#include <hcrypto/sha.h>
-#include <hcrypto/evp.h>
-#include <hcrypto/hmac.h>
-#include <der.h>
-#include "../lib/tsocket/tsocket.h"
-#include "../libcli/security/security.h"
-#include "librpc/gen_ndr/ndr_security.h"
-#include "lib/crypto/arcfour.h"
-#include "libds/common/roles.h"
-#include <gnutls/gnutls.h>
-#include <gnutls/x509.h>
-
-#define DCESRV_INTERFACE_BACKUPKEY_BIND(context, iface) \
- dcesrv_interface_backupkey_bind(context, iface)
-static NTSTATUS dcesrv_interface_backupkey_bind(struct dcesrv_connection_context *context,
- const struct dcesrv_interface *iface)
-{
- return dcesrv_interface_bind_require_privacy(context, iface);
-}
-
-static const unsigned rsa_with_var_num[] = { 1, 2, 840, 113549, 1, 1, 1 };
-/* Equivalent to asn1_oid_id_pkcs1_rsaEncryption*/
-static const AlgorithmIdentifier _hx509_signature_rsa_with_var_num = {
- { 7, discard_const_p(unsigned, rsa_with_var_num) }, NULL
-};
-
-static NTSTATUS set_lsa_secret(TALLOC_CTX *mem_ctx,
- struct ldb_context *ldb,
- const char *name,
- const DATA_BLOB *lsa_secret)
-{
- struct ldb_message *msg;
- struct ldb_result *res;
- struct ldb_dn *domain_dn;
- struct ldb_dn *system_dn;
- struct ldb_val val;
- int ret;
- char *name2;
- struct timeval now = timeval_current();
- NTTIME nt_now = timeval_to_nttime(&now);
- const char *attrs[] = {
- NULL
- };
-
- domain_dn = ldb_get_default_basedn(ldb);
- if (!domain_dn) {
- return NT_STATUS_INTERNAL_ERROR;
- }
-
- msg = ldb_msg_new(mem_ctx);
- if (msg == NULL) {
- return NT_STATUS_NO_MEMORY;
- }
-
- /*
- * This function is a lot like dcesrv_lsa_CreateSecret
- * in the rpc_server/lsa directory
- * The reason why we duplicate the effort here is that:
- * * we want to keep the former function static
- * * we want to avoid the burden of doing LSA calls
- * when we can just manipulate the secrets directly
- * * taillor the function to the particular needs of backup protocol
- */
-
- system_dn = samdb_search_dn(ldb, msg, domain_dn, "(&(objectClass=container)(cn=System))");
- if (system_dn == NULL) {
- talloc_free(msg);
- return NT_STATUS_NO_MEMORY;
- }
-
- name2 = talloc_asprintf(msg, "%s Secret", name);
- if (name2 == NULL) {
- talloc_free(msg);
- return NT_STATUS_NO_MEMORY;
- }
-
- ret = ldb_search(ldb, mem_ctx, &res, system_dn, LDB_SCOPE_SUBTREE, attrs,
- "(&(cn=%s)(objectclass=secret))",
- ldb_binary_encode_string(mem_ctx, name2));
-
- if (ret != LDB_SUCCESS || res->count != 0 ) {
- DEBUG(2, ("Secret %s already exists !\n", name2));
- talloc_free(msg);
- return NT_STATUS_OBJECT_NAME_COLLISION;
- }
-
- /*
- * We don't care about previous value as we are
- * here only if the key didn't exists before
- */
-
- msg->dn = ldb_dn_copy(mem_ctx, system_dn);
- if (msg->dn == NULL) {
- talloc_free(msg);
- return NT_STATUS_NO_MEMORY;
- }
- if (!ldb_dn_add_child_fmt(msg->dn, "cn=%s", name2)) {
- talloc_free(msg);
- return NT_STATUS_NO_MEMORY;
- }
-
- ret = ldb_msg_add_string(msg, "cn", name2);
- if (ret != LDB_SUCCESS) {
- talloc_free(msg);
- return NT_STATUS_NO_MEMORY;
- }
- ret = ldb_msg_add_string(msg, "objectClass", "secret");
- if (ret != LDB_SUCCESS) {
- talloc_free(msg);
- return NT_STATUS_NO_MEMORY;
- }
- ret = samdb_msg_add_uint64(ldb, mem_ctx, msg, "priorSetTime", nt_now);
- if (ret != LDB_SUCCESS) {
- talloc_free(msg);
- return NT_STATUS_NO_MEMORY;
- }
- val.data = lsa_secret->data;
- val.length = lsa_secret->length;
- ret = ldb_msg_add_value(msg, "currentValue", &val, NULL);
- if (ret != LDB_SUCCESS) {
- talloc_free(msg);
- return NT_STATUS_NO_MEMORY;
- }
- ret = samdb_msg_add_uint64(ldb, mem_ctx, msg, "lastSetTime", nt_now);
- if (ret != LDB_SUCCESS) {
- talloc_free(msg);
- return NT_STATUS_NO_MEMORY;
- }
-
- /*
- * create the secret with DSDB_MODIFY_RELAX
- * otherwise dsdb/samdb/ldb_modules/objectclass.c forbid
- * the create of LSA secret object
- */
- ret = dsdb_add(ldb, msg, DSDB_MODIFY_RELAX);
- if (ret != LDB_SUCCESS) {
- DEBUG(2,("Failed to create secret record %s: %s\n",
- ldb_dn_get_linearized(msg->dn),
- ldb_errstring(ldb)));
- talloc_free(msg);
- return NT_STATUS_ACCESS_DENIED;
- }
-
- talloc_free(msg);
- return NT_STATUS_OK;
-}
-
-/* This function is pretty much like dcesrv_lsa_QuerySecret */
-static NTSTATUS get_lsa_secret(TALLOC_CTX *mem_ctx,
- struct ldb_context *ldb,
- const char *name,
- DATA_BLOB *lsa_secret)
-{
- TALLOC_CTX *tmp_mem;
- struct ldb_result *res;
- struct ldb_dn *domain_dn;
- struct ldb_dn *system_dn;
- const struct ldb_val *val;
- uint8_t *data;
- const char *attrs[] = {
- "currentValue",
- NULL
- };
- int ret;
-
- lsa_secret->data = NULL;
- lsa_secret->length = 0;
-
- domain_dn = ldb_get_default_basedn(ldb);
- if (!domain_dn) {
- return NT_STATUS_INTERNAL_ERROR;
- }
-
- tmp_mem = talloc_new(mem_ctx);
- if (tmp_mem == NULL) {
- return NT_STATUS_NO_MEMORY;
- }
-
- system_dn = samdb_search_dn(ldb, tmp_mem, domain_dn, "(&(objectClass=container)(cn=System))");
- if (system_dn == NULL) {
- talloc_free(tmp_mem);
- return NT_STATUS_NO_MEMORY;
- }
-
- ret = ldb_search(ldb, mem_ctx, &res, system_dn, LDB_SCOPE_SUBTREE, attrs,
- "(&(cn=%s Secret)(objectclass=secret))",
- ldb_binary_encode_string(tmp_mem, name));
-
- if (ret != LDB_SUCCESS) {
- talloc_free(tmp_mem);
- return NT_STATUS_INTERNAL_DB_CORRUPTION;
- }
- if (res->count == 0) {
- talloc_free(tmp_mem);
- return NT_STATUS_RESOURCE_NAME_NOT_FOUND;
- }
- if (res->count > 1) {
- DEBUG(2, ("Secret %s collision\n", name));
- talloc_free(tmp_mem);
- return NT_STATUS_INTERNAL_DB_CORRUPTION;
- }
-
- val = ldb_msg_find_ldb_val(res->msgs[0], "currentValue");
- if (val == NULL) {
- /*
- * The secret object is here but we don't have the secret value
- * The most common case is a RODC
- */
- *lsa_secret = data_blob_null;
- talloc_free(tmp_mem);
- return NT_STATUS_OK;
- }
-
- data = val->data;
- lsa_secret->data = talloc_move(mem_ctx, &data);
- lsa_secret->length = val->length;
-
- talloc_free(tmp_mem);
- return NT_STATUS_OK;
-}
-
-static DATA_BLOB *reverse_and_get_blob(TALLOC_CTX *mem_ctx, BIGNUM *bn)
-{
- DATA_BLOB blob;
- DATA_BLOB *rev = talloc(mem_ctx, DATA_BLOB);
- uint32_t i;
-
- blob.length = BN_num_bytes(bn);
- blob.data = talloc_array(mem_ctx, uint8_t, blob.length);
-
- if (blob.data == NULL) {
- return NULL;
- }
-
- BN_bn2bin(bn, blob.data);
-
- rev->data = talloc_array(mem_ctx, uint8_t, blob.length);
- if (rev->data == NULL) {
- return NULL;
- }
-
- for(i=0; i < blob.length; i++) {
- rev->data[i] = blob.data[blob.length - i -1];
- }
- rev->length = blob.length;
- talloc_free(blob.data);
- return rev;
-}
-
-static BIGNUM *reverse_and_get_bignum(TALLOC_CTX *mem_ctx, DATA_BLOB *blob)
-{
- BIGNUM *ret;
- DATA_BLOB rev;
- uint32_t i;
-
- rev.data = talloc_array(mem_ctx, uint8_t, blob->length);
- if (rev.data == NULL) {
- return NULL;
- }
-
- for(i=0; i < blob->length; i++) {
- rev.data[i] = blob->data[blob->length - i -1];
- }
- rev.length = blob->length;
-
- ret = BN_bin2bn(rev.data, rev.length, NULL);
- talloc_free(rev.data);
-
- return ret;
-}
-
-static NTSTATUS get_pk_from_raw_keypair_params(TALLOC_CTX *ctx,
- struct bkrp_exported_RSA_key_pair *keypair,
- hx509_private_key *pk)
-{
- hx509_context hctx;
- RSA *rsa;
- struct hx509_private_key_ops *ops;
- hx509_private_key privkey = NULL;
-
- hx509_context_init(&hctx);
- ops = hx509_find_private_alg(&_hx509_signature_rsa_with_var_num.algorithm);
- if (ops == NULL) {
- DEBUG(2, ("Not supported algorithm\n"));
- hx509_context_free(&hctx);
- return NT_STATUS_INTERNAL_ERROR;
- }
-
- if (hx509_private_key_init(&privkey, ops, NULL) != 0) {
- hx509_context_free(&hctx);
- return NT_STATUS_NO_MEMORY;
- }
-
- rsa = RSA_new();
- if (rsa ==NULL) {
- hx509_private_key_free(&privkey);
- hx509_context_free(&hctx);
- return NT_STATUS_INVALID_PARAMETER;
- }
-
- rsa->n = reverse_and_get_bignum(ctx, &(keypair->modulus));
- if (rsa->n == NULL) {
- RSA_free(rsa);
- hx509_private_key_free(&privkey);
- hx509_context_free(&hctx);
- return NT_STATUS_INVALID_PARAMETER;
- }
- rsa->d = reverse_and_get_bignum(ctx, &(keypair->private_exponent));
- if (rsa->d == NULL) {
- RSA_free(rsa);
- hx509_private_key_free(&privkey);
- hx509_context_free(&hctx);
- return NT_STATUS_INVALID_PARAMETER;
- }
- rsa->p = reverse_and_get_bignum(ctx, &(keypair->prime1));
- if (rsa->p == NULL) {
- RSA_free(rsa);
- hx509_private_key_free(&privkey);
- hx509_context_free(&hctx);
- return NT_STATUS_INVALID_PARAMETER;
- }
- rsa->q = reverse_and_get_bignum(ctx, &(keypair->prime2));
- if (rsa->q == NULL) {
- RSA_free(rsa);
- hx509_private_key_free(&privkey);
- hx509_context_free(&hctx);
- return NT_STATUS_INVALID_PARAMETER;
- }
- rsa->dmp1 = reverse_and_get_bignum(ctx, &(keypair->exponent1));
- if (rsa->dmp1 == NULL) {
- RSA_free(rsa);
- hx509_private_key_free(&privkey);
- hx509_context_free(&hctx);
- return NT_STATUS_INVALID_PARAMETER;
- }
- rsa->dmq1 = reverse_and_get_bignum(ctx, &(keypair->exponent2));
- if (rsa->dmq1 == NULL) {
- RSA_free(rsa);
- hx509_private_key_free(&privkey);
- hx509_context_free(&hctx);
- return NT_STATUS_INVALID_PARAMETER;
- }
- rsa->iqmp = reverse_and_get_bignum(ctx, &(keypair->coefficient));
- if (rsa->iqmp == NULL) {
- RSA_free(rsa);
- hx509_private_key_free(&privkey);
- hx509_context_free(&hctx);
- return NT_STATUS_INVALID_PARAMETER;
- }
- rsa->e = reverse_and_get_bignum(ctx, &(keypair->public_exponent));
- if (rsa->e == NULL) {
- RSA_free(rsa);
- hx509_private_key_free(&privkey);
- hx509_context_free(&hctx);
- return NT_STATUS_INVALID_PARAMETER;
- }
-
- *pk = privkey;
-
- hx509_private_key_assign_rsa(*pk, rsa);
-
- hx509_context_free(&hctx);
- return NT_STATUS_OK;
-}
-
-static WERROR get_and_verify_access_check(TALLOC_CTX *sub_ctx,
- uint32_t version,
- uint8_t *key_and_iv,
- uint8_t *access_check,
- uint32_t access_check_len,
- struct auth_session_info *session_info)
-{
- heim_octet_string iv;
- heim_octet_string access_check_os;
- hx509_crypto crypto;
-
- DATA_BLOB blob_us;
- uint32_t key_len;
- uint32_t iv_len;
- int res;
- enum ndr_err_code ndr_err;
- hx509_context hctx;
-
- struct dom_sid *access_sid = NULL;
- struct dom_sid *caller_sid = NULL;
-
- /* This one should not be freed */
- const AlgorithmIdentifier *alg;
-
- switch (version) {
- case 2:
- key_len = 24;
- iv_len = 8;
- alg = hx509_crypto_des_rsdi_ede3_cbc();
- break;
-
- case 3:
- key_len = 32;
- iv_len = 16;
- alg =hx509_crypto_aes256_cbc();
- break;
-
- default:
- return WERR_INVALID_DATA;
- }
-
- hx509_context_init(&hctx);
- res = hx509_crypto_init(hctx, NULL,
- &(alg->algorithm),
- &crypto);
- hx509_context_free(&hctx);
-
- if (res != 0) {
- return WERR_INVALID_DATA;
- }
-
- res = hx509_crypto_set_key_data(crypto, key_and_iv, key_len);
-
- iv.data = talloc_memdup(sub_ctx, key_len + key_and_iv, iv_len);
- iv.length = iv_len;
-
- if (res != 0) {
- hx509_crypto_destroy(crypto);
- return WERR_INVALID_DATA;
- }
-
- hx509_crypto_set_padding(crypto, HX509_CRYPTO_PADDING_NONE);
- res = hx509_crypto_decrypt(crypto,
- access_check,
- access_check_len,
- &iv,
- &access_check_os);
-
- if (res != 0) {
- hx509_crypto_destroy(crypto);
- return WERR_INVALID_DATA;
- }
-
- blob_us.data = access_check_os.data;
- blob_us.length = access_check_os.length;
-
- hx509_crypto_destroy(crypto);
-
- switch (version) {
- case 2:
- {
- uint32_t hash_size = 20;
- uint8_t hash[hash_size];
- struct sha sctx;
- struct bkrp_access_check_v2 uncrypted_accesscheckv2;
-
- ndr_err = ndr_pull_struct_blob(&blob_us, sub_ctx, &uncrypted_accesscheckv2,
- (ndr_pull_flags_fn_t)ndr_pull_bkrp_access_check_v2);
- if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
- /* Unable to unmarshall */
- der_free_octet_string(&access_check_os);
- return WERR_INVALID_DATA;
- }
- if (uncrypted_accesscheckv2.magic != 0x1) {
- /* wrong magic */
- der_free_octet_string(&access_check_os);
- return WERR_INVALID_DATA;
- }
-
- SHA1_Init(&sctx);
- SHA1_Update(&sctx, blob_us.data, blob_us.length - hash_size);
- SHA1_Final(hash, &sctx);
- der_free_octet_string(&access_check_os);
- /*
- * We free it after the sha1 calculation because blob.data
- * point to the same area
- */
-
- if (memcmp(hash, uncrypted_accesscheckv2.hash, hash_size) != 0) {
- DEBUG(2, ("Wrong hash value in the access check in backup key remote protocol\n"));
- return WERR_INVALID_DATA;
- }
- access_sid = &(uncrypted_accesscheckv2.sid);
- break;
- }
- case 3:
- {
- uint32_t hash_size = 64;
- uint8_t hash[hash_size];
- struct hc_sha512state sctx;
- struct bkrp_access_check_v3 uncrypted_accesscheckv3;
-
- ndr_err = ndr_pull_struct_blob(&blob_us, sub_ctx, &uncrypted_accesscheckv3,
- (ndr_pull_flags_fn_t)ndr_pull_bkrp_access_check_v3);
- if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
- /* Unable to unmarshall */
- der_free_octet_string(&access_check_os);
- return WERR_INVALID_DATA;
- }
- if (uncrypted_accesscheckv3.magic != 0x1) {
- /* wrong magic */
- der_free_octet_string(&access_check_os);
- return WERR_INVALID_DATA;
- }
-
- SHA512_Init(&sctx);
- SHA512_Update(&sctx, blob_us.data, blob_us.length - hash_size);
- SHA512_Final(hash, &sctx);
- der_free_octet_string(&access_check_os);
- /*
- * We free it after the sha1 calculation because blob.data
- * point to the same area
- */
-
- if (memcmp(hash, uncrypted_accesscheckv3.hash, hash_size) != 0) {
- DEBUG(2, ("Wrong hash value in the access check in backup key remote protocol\n"));
- return WERR_INVALID_DATA;
- }
- access_sid = &(uncrypted_accesscheckv3.sid);
- break;
- }
- default:
- /* Never reached normally as we filtered at the switch / case level */
- return WERR_INVALID_DATA;
- }
-
- caller_sid = &session_info->security_token->sids[PRIMARY_USER_SID_INDEX];
-
- if (!dom_sid_equal(caller_sid, access_sid)) {
- return WERR_INVALID_ACCESS;
- }
- return WERR_OK;
-}
-
-/*
- * We have some data, such as saved website or IMAP passwords that the
- * client has in profile on-disk. This needs to be decrypted. This
- * version gives the server the data over the network (protected by
- * the X.509 certificate and public key encryption, and asks that it
- * be decrypted returned for short-term use, protected only by the
- * negotiated transport encryption.
- *
- * The data is NOT stored in the LSA, but a X.509 certificate, public
- * and private keys used to encrypt the data will be stored. There is
- * only one active encryption key pair and certificate per domain, it
- * is pointed at with G$BCKUPKEY_PREFERRED in the LSA secrets store.
- *
- * The potentially multiple valid decrypting key pairs are in turn
- * stored in the LSA secrets store as G$BCKUPKEY_keyGuidString.
- *
- */
-static WERROR bkrp_client_wrap_decrypt_data(struct dcesrv_call_state *dce_call,
- TALLOC_CTX *mem_ctx,
- struct bkrp_BackupKey *r,
- struct ldb_context *ldb_ctx)
-{
- struct auth_session_info *session_info =
- dcesrv_call_session_info(dce_call);
- struct bkrp_client_side_wrapped uncrypt_request;
- DATA_BLOB blob;
- enum ndr_err_code ndr_err;
- char *guid_string;
- char *cert_secret_name;
- DATA_BLOB lsa_secret;
- DATA_BLOB *uncrypted_data = NULL;
- NTSTATUS status;
- uint32_t requested_version;
-
- blob.data = r->in.data_in;
- blob.length = r->in.data_in_len;
-
- if (r->in.data_in_len < 4 || r->in.data_in == NULL) {
- return WERR_INVALID_PARAMETER;
- }
-
- /*
- * We check for the version here, so we can actually print the
- * message as we are unlikely to parse it with NDR.
- */
- requested_version = IVAL(r->in.data_in, 0);
- if ((requested_version != BACKUPKEY_CLIENT_WRAP_VERSION2)
- && (requested_version != BACKUPKEY_CLIENT_WRAP_VERSION3)) {
- DEBUG(1, ("Request for unknown BackupKey sub-protocol %d\n", requested_version));
- return WERR_INVALID_PARAMETER;
- }
-
- ndr_err = ndr_pull_struct_blob(&blob, mem_ctx, &uncrypt_request,
- (ndr_pull_flags_fn_t)ndr_pull_bkrp_client_side_wrapped);
- if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
- return WERR_INVALID_PARAMETER;
- }
-
- if ((uncrypt_request.version != BACKUPKEY_CLIENT_WRAP_VERSION2)
- && (uncrypt_request.version != BACKUPKEY_CLIENT_WRAP_VERSION3)) {
- DEBUG(1, ("Request for unknown BackupKey sub-protocol %d\n", uncrypt_request.version));
- return WERR_INVALID_PARAMETER;
- }
-
- guid_string = GUID_string(mem_ctx, &uncrypt_request.guid);
- if (guid_string == NULL) {
- return WERR_NOT_ENOUGH_MEMORY;
- }
-
- cert_secret_name = talloc_asprintf(mem_ctx,
- "BCKUPKEY_%s",
- guid_string);
- if (cert_secret_name == NULL) {
- return WERR_NOT_ENOUGH_MEMORY;
- }
-
- status = get_lsa_secret(mem_ctx,
- ldb_ctx,
- cert_secret_name,
- &lsa_secret);
- if (!NT_STATUS_IS_OK(status)) {
- DEBUG(10, ("Error while fetching secret %s\n", cert_secret_name));
- return WERR_INVALID_DATA;
- } else if (lsa_secret.length == 0) {
- /* we do not have the real secret attribute, like if we are an RODC */
- return WERR_INVALID_PARAMETER;
- } else {
- hx509_context hctx;
- struct bkrp_exported_RSA_key_pair keypair;
- hx509_private_key pk;
- uint32_t i, res;
- heim_octet_string reversed_secret;
- heim_octet_string uncrypted_secret;
- AlgorithmIdentifier alg;
- DATA_BLOB blob_us;
- WERROR werr;
-
- ndr_err = ndr_pull_struct_blob(&lsa_secret, mem_ctx, &keypair, (ndr_pull_flags_fn_t)ndr_pull_bkrp_exported_RSA_key_pair);
- if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
- DEBUG(2, ("Unable to parse the ndr encoded cert in key %s\n", cert_secret_name));
- return WERR_FILE_NOT_FOUND;
- }
-
- status = get_pk_from_raw_keypair_params(mem_ctx, &keypair, &pk);
- if (!NT_STATUS_IS_OK(status)) {
- return WERR_INTERNAL_ERROR;
- }
-
- reversed_secret.data = talloc_array(mem_ctx, uint8_t,
- uncrypt_request.encrypted_secret_len);
- if (reversed_secret.data == NULL) {
- hx509_private_key_free(&pk);
- return WERR_NOT_ENOUGH_MEMORY;
- }
-
- /* The secret has to be reversed ... */
- for(i=0; i< uncrypt_request.encrypted_secret_len; i++) {
- uint8_t *reversed = (uint8_t *)reversed_secret.data;
- uint8_t *uncrypt = uncrypt_request.encrypted_secret;
- reversed[i] = uncrypt[uncrypt_request.encrypted_secret_len - 1 - i];
- }
- reversed_secret.length = uncrypt_request.encrypted_secret_len;
-
- /*
- * Let's try to decrypt the secret now that
- * we have the private key ...
- */
- hx509_context_init(&hctx);
- res = hx509_private_key_private_decrypt(hctx, &reversed_secret,
- &alg.algorithm, pk,
- &uncrypted_secret);
- hx509_context_free(&hctx);
- hx509_private_key_free(&pk);
- if (res != 0) {
- /* We are not able to decrypt the secret, looks like something is wrong */
- return WERR_INVALID_PARAMETER;
- }
- blob_us.data = uncrypted_secret.data;
- blob_us.length = uncrypted_secret.length;
-
- if (uncrypt_request.version == 2) {
- struct bkrp_encrypted_secret_v2 uncrypted_secretv2;
-
- ndr_err = ndr_pull_struct_blob(&blob_us, mem_ctx, &uncrypted_secretv2,
- (ndr_pull_flags_fn_t)ndr_pull_bkrp_encrypted_secret_v2);
- der_free_octet_string(&uncrypted_secret);
- if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
- /* Unable to unmarshall */
- return WERR_INVALID_DATA;
- }
- if (uncrypted_secretv2.magic != 0x20) {
- /* wrong magic */
- return WERR_INVALID_DATA;
- }
-
- werr = get_and_verify_access_check(mem_ctx, 2,
- uncrypted_secretv2.payload_key,
- uncrypt_request.access_check,
- uncrypt_request.access_check_len,
- session_info);
- if (!W_ERROR_IS_OK(werr)) {
- return werr;
- }
- uncrypted_data = talloc(mem_ctx, DATA_BLOB);
- if (uncrypted_data == NULL) {
- return WERR_INVALID_DATA;
- }
-
- uncrypted_data->data = uncrypted_secretv2.secret;
- uncrypted_data->length = uncrypted_secretv2.secret_len;
- }
- if (uncrypt_request.version == 3) {
- struct bkrp_encrypted_secret_v3 uncrypted_secretv3;
-
- ndr_err = ndr_pull_struct_blob(&blob_us, mem_ctx, &uncrypted_secretv3,
- (ndr_pull_flags_fn_t)ndr_pull_bkrp_encrypted_secret_v3);
-
- der_free_octet_string(&uncrypted_secret);
- if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
- /* Unable to unmarshall */
- return WERR_INVALID_DATA;
- }
-
- if (uncrypted_secretv3.magic1 != 0x30 ||
- uncrypted_secretv3.magic2 != 0x6610 ||
- uncrypted_secretv3.magic3 != 0x800e) {
- /* wrong magic */
- return WERR_INVALID_DATA;
- }
-
- /*
- * Confirm that the caller is permitted to
- * read this particular data. Because one key
- * pair is used per domain, the caller could
- * have stolen the profile data on-disk and
- * would otherwise be able to read the
- * passwords.
- */
-
- werr = get_and_verify_access_check(mem_ctx, 3,
- uncrypted_secretv3.payload_key,
- uncrypt_request.access_check,
- uncrypt_request.access_check_len,
- session_info);
- if (!W_ERROR_IS_OK(werr)) {
- return werr;
- }
-
- uncrypted_data = talloc(mem_ctx, DATA_BLOB);
- if (uncrypted_data == NULL) {
- return WERR_INVALID_DATA;
- }
-
- uncrypted_data->data = uncrypted_secretv3.secret;
- uncrypted_data->length = uncrypted_secretv3.secret_len;
- }
-
- /*
- * Yeah if we are here all looks pretty good:
- * - hash is ok
- * - user sid is the same as the one in access check
- * - we were able to decrypt the whole stuff
- */
- }
-
- if (uncrypted_data->data == NULL) {
- return WERR_INVALID_DATA;
- }
-
- /* There is a magic value a the beginning of the data
- * we can use an adhoc structure but as the
- * parent structure is just an array of bytes it a lot of work
- * work just prepending 4 bytes
- */
- *(r->out.data_out) = talloc_zero_array(mem_ctx, uint8_t, uncrypted_data->length + 4);
- W_ERROR_HAVE_NO_MEMORY(*(r->out.data_out));
- memcpy(4+*(r->out.data_out), uncrypted_data->data, uncrypted_data->length);
- *(r->out.data_out_len) = uncrypted_data->length + 4;
-
- return WERR_OK;
-}
-
-/*
- * Strictly, this function no longer uses Heimdal in order to generate an RSA
- * key, but GnuTLS.
- *
- * The resulting key is then imported into Heimdal's RSA structure.
- *
- * We use GnuTLS because it can reliably generate 2048 bit keys every time.
- * Windows clients strictly require 2048, no more since it won't fit and no
- * less either. Heimdal would almost always generate a smaller key.
- */
-static WERROR create_heimdal_rsa_key(TALLOC_CTX *ctx, hx509_context *hctx,
- hx509_private_key *pk, RSA **rsa)
-{
- int ret;
- uint8_t *p0 = NULL;
- const uint8_t *p;
- size_t len;
- int bits = 2048;
- int RSA_returned_bits;
- gnutls_x509_privkey_t gtls_key;
- WERROR werr;
-
- *rsa = NULL;
-
- ret = gnutls_global_init();
- if (ret != GNUTLS_E_SUCCESS) {
- DBG_ERR("TLS error: %s\n", gnutls_strerror(ret));
- return WERR_INTERNAL_ERROR;
- }
-
- ret = gnutls_x509_privkey_init(>ls_key);
- if (ret != 0) {
- gnutls_global_deinit();
- return WERR_INTERNAL_ERROR;
- }
-
- /*
- * Unlike Heimdal's RSA_generate_key_ex(), this generates a
- * 2048 bit key 100% of the time. The heimdal code had a ~1/8
- * chance of doing so, chewing vast quantities of computation
- * and entropy in the process.
- */
-
- ret = gnutls_x509_privkey_generate(gtls_key, GNUTLS_PK_RSA, bits, 0);
- if (ret != 0) {
- werr = WERR_INTERNAL_ERROR;
- goto done;
- }
-
- /* No need to check error code, this SHOULD fail */
- gnutls_x509_privkey_export(gtls_key, GNUTLS_X509_FMT_DER, NULL, &len);
-
- if (len < 1) {
- werr = WERR_INTERNAL_ERROR;
- goto done;
- }
-
- p0 = talloc_size(ctx, len);
- if (p0 == NULL) {
- werr = WERR_NOT_ENOUGH_MEMORY;
- goto done;
- }
- p = p0;
-
- /*
- * Only this GnuTLS export function correctly exports the key,
- * we can't use gnutls_rsa_params_export_raw() because while
- * it appears to be fixed in more recent versions, in the
- * Ubuntu 14.04 version 2.12.23 (at least) it incorrectly
- * exports one of the key parameters (qInv). Additionally, we
- * would have to work around subtle differences in big number
- * representations.
- *
- * We need access to the RSA parameters directly (in the
- * parameter RSA **rsa) as the caller has to manually encode
- * them in a non-standard data structure.
- */
- ret = gnutls_x509_privkey_export(gtls_key, GNUTLS_X509_FMT_DER, p0, &len);
-
- if (ret != 0) {
- werr = WERR_INTERNAL_ERROR;
- goto done;
- }
-
- /*
- * To dump the key we can use :
- * rk_dumpdata("h5lkey", p0, len);
- */
- ret = hx509_parse_private_key(*hctx, &_hx509_signature_rsa_with_var_num ,
- p0, len, HX509_KEY_FORMAT_DER, pk);
-
- if (ret != 0) {
- werr = WERR_INTERNAL_ERROR;
- goto done;
- }
-
- *rsa = d2i_RSAPrivateKey(NULL, &p, len);
- TALLOC_FREE(p0);
-
- if (*rsa == NULL) {
- hx509_private_key_free(pk);
- werr = WERR_INTERNAL_ERROR;
- goto done;
- }
-
- RSA_returned_bits = BN_num_bits((*rsa)->n);
- DEBUG(6, ("GnuTLS returned an RSA private key with %d bits\n", RSA_returned_bits));
-
- if (RSA_returned_bits != bits) {
- DEBUG(0, ("GnuTLS unexpectedly returned an RSA private key with %d bits, needed %d\n", RSA_returned_bits, bits));
- hx509_private_key_free(pk);
- werr = WERR_INTERNAL_ERROR;
- goto done;
- }
-
- werr = WERR_OK;
-
-done:
- if (p0 != NULL) {
- memset(p0, 0, len);
- TALLOC_FREE(p0);
- }
-
- gnutls_x509_privkey_deinit(gtls_key);
- gnutls_global_deinit();
- return werr;
-}
-
-static WERROR self_sign_cert(TALLOC_CTX *ctx, hx509_context *hctx, hx509_request *req,
- time_t lifetime, hx509_private_key *private_key,
- hx509_cert *cert, DATA_BLOB *guidblob)
-{
- SubjectPublicKeyInfo spki;
- hx509_name subject = NULL;
- hx509_ca_tbs tbs;
- struct heim_bit_string uniqueid;
- struct heim_integer serialnumber;
- int ret, i;
-
- uniqueid.data = talloc_memdup(ctx, guidblob->data, guidblob->length);
- if (uniqueid.data == NULL) {
- return WERR_NOT_ENOUGH_MEMORY;
- }
- /* uniqueid is a bit string in which each byte represent 1 bit (1 or 0)
- * so as 1 byte is 8 bits we need to provision 8 times more space as in the
- * blob
- */
- uniqueid.length = 8 * guidblob->length;
-
- serialnumber.data = talloc_array(ctx, uint8_t,
- guidblob->length);
- if (serialnumber.data == NULL) {
- talloc_free(uniqueid.data);
- return WERR_NOT_ENOUGH_MEMORY;
- }
-
- /* Native AD generates certificates with serialnumber in reversed notation */
- for (i = 0; i < guidblob->length; i++) {
- uint8_t *reversed = (uint8_t *)serialnumber.data;
- uint8_t *uncrypt = guidblob->data;
- reversed[i] = uncrypt[guidblob->length - 1 - i];
- }
- serialnumber.length = guidblob->length;
- serialnumber.negative = 0;
-
- memset(&spki, 0, sizeof(spki));
-
- ret = hx509_request_get_name(*hctx, *req, &subject);
- if (ret !=0) {
- goto fail_subject;
- }
- ret = hx509_request_get_SubjectPublicKeyInfo(*hctx, *req, &spki);
- if (ret !=0) {
- goto fail_spki;
- }
-
- ret = hx509_ca_tbs_init(*hctx, &tbs);
- if (ret !=0) {
- goto fail_tbs;
- }
-
- ret = hx509_ca_tbs_set_spki(*hctx, tbs, &spki);
- if (ret !=0) {
- goto fail;
- }
- ret = hx509_ca_tbs_set_subject(*hctx, tbs, subject);
- if (ret !=0) {
- goto fail;
- }
- ret = hx509_ca_tbs_set_notAfter_lifetime(*hctx, tbs, lifetime);
- if (ret !=0) {
- goto fail;
- }
- ret = hx509_ca_tbs_set_unique(*hctx, tbs, &uniqueid, &uniqueid);
- if (ret !=0) {
- goto fail;
- }
- ret = hx509_ca_tbs_set_serialnumber(*hctx, tbs, &serialnumber);
- if (ret !=0) {
- goto fail;
- }
- ret = hx509_ca_sign_self(*hctx, tbs, *private_key, cert);
- if (ret !=0) {
- goto fail;
- }
- hx509_name_free(&subject);
- free_SubjectPublicKeyInfo(&spki);
- hx509_ca_tbs_free(&tbs);
-
- return WERR_OK;
-
-fail:
- hx509_ca_tbs_free(&tbs);
-fail_tbs:
- free_SubjectPublicKeyInfo(&spki);
-fail_spki:
- hx509_name_free(&subject);
-fail_subject:
- talloc_free(uniqueid.data);
- talloc_free(serialnumber.data);
- return WERR_INTERNAL_ERROR;
-}
-
-static WERROR create_req(TALLOC_CTX *ctx, hx509_context *hctx, hx509_request *req,
- hx509_private_key *signer,RSA **rsa, const char *dn)
-{
- int ret;
- SubjectPublicKeyInfo key;
-
- hx509_name name;
- WERROR werr;
-
- werr = create_heimdal_rsa_key(ctx, hctx, signer, rsa);
- if (!W_ERROR_IS_OK(werr)) {
- return werr;
- }
-
- hx509_request_init(*hctx, req);
- ret = hx509_parse_name(*hctx, dn, &name);
- if (ret != 0) {
- RSA_free(*rsa);
- hx509_private_key_free(signer);
- hx509_request_free(req);
- hx509_name_free(&name);
- return WERR_INTERNAL_ERROR;
- }
-
- ret = hx509_request_set_name(*hctx, *req, name);
- if (ret != 0) {
- RSA_free(*rsa);
- hx509_private_key_free(signer);
- hx509_request_free(req);
- hx509_name_free(&name);
- return WERR_INTERNAL_ERROR;
- }
- hx509_name_free(&name);
-
- ret = hx509_private_key2SPKI(*hctx, *signer, &key);
- if (ret != 0) {
- RSA_free(*rsa);
- hx509_private_key_free(signer);
- hx509_request_free(req);
- return WERR_INTERNAL_ERROR;
- }
- ret = hx509_request_set_SubjectPublicKeyInfo(*hctx, *req, &key);
- if (ret != 0) {
- RSA_free(*rsa);
- hx509_private_key_free(signer);
- free_SubjectPublicKeyInfo(&key);
- hx509_request_free(req);
- return WERR_INTERNAL_ERROR;
- }
-
- free_SubjectPublicKeyInfo(&key);
-
- return WERR_OK;
-}
-
-/* Return an error when we fail to generate a certificate */
-static WERROR generate_bkrp_cert(TALLOC_CTX *ctx, struct dcesrv_call_state *dce_call, struct ldb_context *ldb_ctx, const char *dn)
-{
- heim_octet_string data;
- WERROR werr;
- RSA *rsa;
- hx509_context hctx;
- hx509_private_key pk;
- hx509_request req;
- hx509_cert cert;
- DATA_BLOB blob;
- DATA_BLOB blobkeypair;
- DATA_BLOB *tmp;
- int ret;
- bool ok = true;
- struct GUID guid = GUID_random();
- NTSTATUS status;
- char *secret_name;
- struct bkrp_exported_RSA_key_pair keypair;
- enum ndr_err_code ndr_err;
- uint32_t nb_seconds_validity = 3600 * 24 * 365;
-
- DEBUG(6, ("Trying to generate a certificate\n"));
- hx509_context_init(&hctx);
- werr = create_req(ctx, &hctx, &req, &pk, &rsa, dn);
- if (!W_ERROR_IS_OK(werr)) {
- hx509_context_free(&hctx);
- return werr;
- }
-
- status = GUID_to_ndr_blob(&guid, ctx, &blob);
- if (!NT_STATUS_IS_OK(status)) {
- hx509_context_free(&hctx);
- hx509_private_key_free(&pk);
- RSA_free(rsa);
- return WERR_INVALID_DATA;
- }
-
- werr = self_sign_cert(ctx, &hctx, &req, nb_seconds_validity, &pk, &cert, &blob);
- if (!W_ERROR_IS_OK(werr)) {
- hx509_private_key_free(&pk);
- hx509_context_free(&hctx);
- return WERR_INVALID_DATA;
- }
-
- ret = hx509_cert_binary(hctx, cert, &data);
- if (ret !=0) {
- hx509_cert_free(cert);
- hx509_private_key_free(&pk);
- hx509_context_free(&hctx);
- return WERR_INVALID_DATA;
- }
-
- keypair.cert.data = talloc_memdup(ctx, data.data, data.length);
- keypair.cert.length = data.length;
-
- /*
- * Heimdal's bignum are big endian and the
- * structure expect it to be in little endian
- * so we reverse the buffer to make it work
- */
- tmp = reverse_and_get_blob(ctx, rsa->e);
- if (tmp == NULL) {
- ok = false;
- } else {
- keypair.public_exponent = *tmp;
- SMB_ASSERT(tmp->length <= 4);
- /*
- * The value is now in little endian but if can happen that the length is
- * less than 4 bytes.
- * So if we have less than 4 bytes we pad with zeros so that it correctly
- * fit into the structure.
- */
- if (tmp->length < 4) {
- /*
- * We need the expo to fit 4 bytes
- */
- keypair.public_exponent.data = talloc_zero_array(ctx, uint8_t, 4);
- memcpy(keypair.public_exponent.data, tmp->data, tmp->length);
- keypair.public_exponent.length = 4;
- }
- }
-
- tmp = reverse_and_get_blob(ctx,rsa->d);
- if (tmp == NULL) {
- ok = false;
- } else {
- keypair.private_exponent = *tmp;
- }
-
- tmp = reverse_and_get_blob(ctx,rsa->n);
- if (tmp == NULL) {
- ok = false;
- } else {
- keypair.modulus = *tmp;
- }
-
- tmp = reverse_and_get_blob(ctx,rsa->p);
- if (tmp == NULL) {
- ok = false;
- } else {
- keypair.prime1 = *tmp;
- }
-
- tmp = reverse_and_get_blob(ctx,rsa->q);
- if (tmp == NULL) {
- ok = false;
- } else {
- keypair.prime2 = *tmp;
- }
-
- tmp = reverse_and_get_blob(ctx,rsa->dmp1);
- if (tmp == NULL) {
- ok = false;
- } else {
- keypair.exponent1 = *tmp;
- }
-
- tmp = reverse_and_get_blob(ctx,rsa->dmq1);
- if (tmp == NULL) {
- ok = false;
- } else {
- keypair.exponent2 = *tmp;
- }
-
- tmp = reverse_and_get_blob(ctx,rsa->iqmp);
- if (tmp == NULL) {
- ok = false;
- } else {
- keypair.coefficient = *tmp;
- }
-
- /* One of the keypair allocation was wrong */
- if (ok == false) {
- der_free_octet_string(&data);
- hx509_cert_free(cert);
- hx509_private_key_free(&pk);
- hx509_context_free(&hctx);
- RSA_free(rsa);
- return WERR_INVALID_DATA;
- }
- keypair.certificate_len = keypair.cert.length;
- ndr_err = ndr_push_struct_blob(&blobkeypair, ctx, &keypair, (ndr_push_flags_fn_t)ndr_push_bkrp_exported_RSA_key_pair);
- if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
- der_free_octet_string(&data);
- hx509_cert_free(cert);
- hx509_private_key_free(&pk);
- hx509_context_free(&hctx);
- RSA_free(rsa);
- return WERR_INVALID_DATA;
- }
-
- secret_name = talloc_asprintf(ctx, "BCKUPKEY_%s", GUID_string(ctx, &guid));
- if (secret_name == NULL) {
- der_free_octet_string(&data);
- hx509_cert_free(cert);
- hx509_private_key_free(&pk);
- hx509_context_free(&hctx);
- RSA_free(rsa);
- return WERR_OUTOFMEMORY;
- }
-
- status = set_lsa_secret(ctx, ldb_ctx, secret_name, &blobkeypair);
- if (!NT_STATUS_IS_OK(status)) {
- DEBUG(2, ("Failed to save the secret %s\n", secret_name));
- }
- talloc_free(secret_name);
-
- GUID_to_ndr_blob(&guid, ctx, &blob);
- status = set_lsa_secret(ctx, ldb_ctx, "BCKUPKEY_PREFERRED", &blob);
- if (!NT_STATUS_IS_OK(status)) {
- DEBUG(2, ("Failed to save the secret BCKUPKEY_PREFERRED\n"));
- }
-
- der_free_octet_string(&data);
- hx509_cert_free(cert);
- hx509_private_key_free(&pk);
- hx509_context_free(&hctx);
- RSA_free(rsa);
- return WERR_OK;
-}
-
-static WERROR bkrp_retrieve_client_wrap_key(struct dcesrv_call_state *dce_call, TALLOC_CTX *mem_ctx,
- struct bkrp_BackupKey *r, struct ldb_context *ldb_ctx)
-{
- struct GUID guid;
- char *guid_string;
- DATA_BLOB lsa_secret;
- enum ndr_err_code ndr_err;
- NTSTATUS status;
-
- /*
- * here we basicaly need to return our certificate
- * search for lsa secret BCKUPKEY_PREFERRED first
- */
-
- status = get_lsa_secret(mem_ctx,
- ldb_ctx,
- "BCKUPKEY_PREFERRED",
- &lsa_secret);
- if (NT_STATUS_EQUAL(status, NT_STATUS_RESOURCE_NAME_NOT_FOUND)) {
- /* Ok we can be in this case if there was no certs */
- struct loadparm_context *lp_ctx = dce_call->conn->dce_ctx->lp_ctx;
- char *dn = talloc_asprintf(mem_ctx, "CN=%s",
- lpcfg_realm(lp_ctx));
-
- WERROR werr = generate_bkrp_cert(mem_ctx, dce_call, ldb_ctx, dn);
- if (!W_ERROR_IS_OK(werr)) {
- return WERR_INVALID_PARAMETER;
- }
- status = get_lsa_secret(mem_ctx,
- ldb_ctx,
- "BCKUPKEY_PREFERRED",
- &lsa_secret);
-
- if (!NT_STATUS_IS_OK(status)) {
- /* Ok we really don't manage to get this certs ...*/
- DEBUG(2, ("Unable to locate BCKUPKEY_PREFERRED after cert generation\n"));
- return WERR_FILE_NOT_FOUND;
- }
- } else if (!NT_STATUS_IS_OK(status)) {
- return WERR_INTERNAL_ERROR;
- }
-
- if (lsa_secret.length == 0) {
- DEBUG(1, ("No secret in BCKUPKEY_PREFERRED, are we an undetected RODC?\n"));
- return WERR_INTERNAL_ERROR;
- } else {
- char *cert_secret_name;
-
- status = GUID_from_ndr_blob(&lsa_secret, &guid);
- if (!NT_STATUS_IS_OK(status)) {
- return WERR_FILE_NOT_FOUND;
- }
-
- guid_string = GUID_string(mem_ctx, &guid);
- if (guid_string == NULL) {
- /* We return file not found because the client
- * expect this error
- */
- return WERR_FILE_NOT_FOUND;
- }
-
- cert_secret_name = talloc_asprintf(mem_ctx,
- "BCKUPKEY_%s",
- guid_string);
- status = get_lsa_secret(mem_ctx,
- ldb_ctx,
- cert_secret_name,
- &lsa_secret);
- if (!NT_STATUS_IS_OK(status)) {
- return WERR_FILE_NOT_FOUND;
- }
-
- if (lsa_secret.length != 0) {
- struct bkrp_exported_RSA_key_pair keypair;
- ndr_err = ndr_pull_struct_blob(&lsa_secret, mem_ctx, &keypair,
- (ndr_pull_flags_fn_t)ndr_pull_bkrp_exported_RSA_key_pair);
- if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
- return WERR_FILE_NOT_FOUND;
- }
- *(r->out.data_out_len) = keypair.cert.length;
- *(r->out.data_out) = talloc_memdup(mem_ctx, keypair.cert.data, keypair.cert.length);
- W_ERROR_HAVE_NO_MEMORY(*(r->out.data_out));
- return WERR_OK;
- } else {
- DEBUG(1, ("No or broken secret called %s\n", cert_secret_name));
- return WERR_INTERNAL_ERROR;
- }
- }
-
- return WERR_NOT_SUPPORTED;
-}
-
-static WERROR generate_bkrp_server_wrap_key(TALLOC_CTX *ctx, struct ldb_context *ldb_ctx)
-{
- struct GUID guid = GUID_random();
- enum ndr_err_code ndr_err;
- DATA_BLOB blob_wrap_key, guid_blob;
- struct bkrp_dc_serverwrap_key wrap_key;
- NTSTATUS status;
- char *secret_name;
- TALLOC_CTX *frame = talloc_stackframe();
-
- generate_random_buffer(wrap_key.key, sizeof(wrap_key.key));
-
- ndr_err = ndr_push_struct_blob(&blob_wrap_key, ctx, &wrap_key, (ndr_push_flags_fn_t)ndr_push_bkrp_dc_serverwrap_key);
- if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
- TALLOC_FREE(frame);
- return WERR_INVALID_DATA;
- }
-
- secret_name = talloc_asprintf(frame, "BCKUPKEY_%s", GUID_string(ctx, &guid));
- if (secret_name == NULL) {
- TALLOC_FREE(frame);
- return WERR_NOT_ENOUGH_MEMORY;
- }
-
- status = set_lsa_secret(frame, ldb_ctx, secret_name, &blob_wrap_key);
- if (!NT_STATUS_IS_OK(status)) {
- DEBUG(2, ("Failed to save the secret %s\n", secret_name));
- TALLOC_FREE(frame);
- return WERR_INTERNAL_ERROR;
- }
-
- status = GUID_to_ndr_blob(&guid, frame, &guid_blob);
- if (!NT_STATUS_IS_OK(status)) {
- DEBUG(2, ("Failed to save the secret %s\n", secret_name));
- TALLOC_FREE(frame);
- }
-
- status = set_lsa_secret(frame, ldb_ctx, "BCKUPKEY_P", &guid_blob);
- if (!NT_STATUS_IS_OK(status)) {
- DEBUG(2, ("Failed to save the secret %s\n", secret_name));
- TALLOC_FREE(frame);
- return WERR_INTERNAL_ERROR;
- }
-
- TALLOC_FREE(frame);
-
- return WERR_OK;
-}
-
-/*
- * Find the specified decryption keys from the LSA secrets store as
- * G$BCKUPKEY_keyGuidString.
- */
-
-static WERROR bkrp_do_retrieve_server_wrap_key(TALLOC_CTX *mem_ctx, struct ldb_context *ldb_ctx,
- struct bkrp_dc_serverwrap_key *server_key,
- struct GUID *guid)
-{
- NTSTATUS status;
- DATA_BLOB lsa_secret;
- char *secret_name;
- char *guid_string;
- enum ndr_err_code ndr_err;
-
- guid_string = GUID_string(mem_ctx, guid);
- if (guid_string == NULL) {
- /* We return file not found because the client
- * expect this error
- */
- return WERR_FILE_NOT_FOUND;
- }
-
- secret_name = talloc_asprintf(mem_ctx, "BCKUPKEY_%s", guid_string);
- if (secret_name == NULL) {
- return WERR_NOT_ENOUGH_MEMORY;
- }
-
- status = get_lsa_secret(mem_ctx, ldb_ctx, secret_name, &lsa_secret);
- if (!NT_STATUS_IS_OK(status)) {
- DEBUG(10, ("Error while fetching secret %s\n", secret_name));
- return WERR_INVALID_DATA;
- }
- if (lsa_secret.length == 0) {
- /* RODC case, we do not have secrets locally */
- DEBUG(1, ("Unable to fetch value for secret %s, are we an undetected RODC?\n",
- secret_name));
- return WERR_INTERNAL_ERROR;
- }
- ndr_err = ndr_pull_struct_blob(&lsa_secret, mem_ctx, server_key,
- (ndr_pull_flags_fn_t)ndr_pull_bkrp_dc_serverwrap_key);
- if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
- DEBUG(2, ("Unable to parse the ndr encoded server wrap key %s\n", secret_name));
- return WERR_INVALID_DATA;
- }
-
- return WERR_OK;
-}
-
-/*
- * Find the current, preferred ServerWrap Key by looking at
- * G$BCKUPKEY_P in the LSA secrets store.
- *
- * Then find the current decryption keys from the LSA secrets store as
- * G$BCKUPKEY_keyGuidString.
- */
-
-static WERROR bkrp_do_retrieve_default_server_wrap_key(TALLOC_CTX *mem_ctx,
- struct ldb_context *ldb_ctx,
- struct bkrp_dc_serverwrap_key *server_key,
- struct GUID *returned_guid)
-{
- NTSTATUS status;
- DATA_BLOB guid_binary;
-
- status = get_lsa_secret(mem_ctx, ldb_ctx, "BCKUPKEY_P", &guid_binary);
- if (!NT_STATUS_IS_OK(status)) {
- DEBUG(10, ("Error while fetching secret BCKUPKEY_P to find current GUID\n"));
- return WERR_FILE_NOT_FOUND;
- } else if (guid_binary.length == 0) {
- /* RODC case, we do not have secrets locally */
- DEBUG(1, ("Unable to fetch value for secret BCKUPKEY_P, are we an undetected RODC?\n"));
- return WERR_INTERNAL_ERROR;
- }
-
- status = GUID_from_ndr_blob(&guid_binary, returned_guid);
- if (!NT_STATUS_IS_OK(status)) {
- return WERR_FILE_NOT_FOUND;
- }
-
- return bkrp_do_retrieve_server_wrap_key(mem_ctx, ldb_ctx,
- server_key, returned_guid);
-}
-
-static WERROR bkrp_server_wrap_decrypt_data(struct dcesrv_call_state *dce_call, TALLOC_CTX *mem_ctx,
- struct bkrp_BackupKey *r ,struct ldb_context *ldb_ctx)
-{
- struct auth_session_info *session_info =
- dcesrv_call_session_info(dce_call);
- WERROR werr;
- struct bkrp_server_side_wrapped decrypt_request;
- DATA_BLOB sid_blob, encrypted_blob, symkey_blob;
- DATA_BLOB blob;
- enum ndr_err_code ndr_err;
- struct bkrp_dc_serverwrap_key server_key;
- struct bkrp_rc4encryptedpayload rc4payload;
- struct dom_sid *caller_sid;
- uint8_t symkey[20]; /* SHA-1 hash len */
- uint8_t mackey[20]; /* SHA-1 hash len */
- uint8_t mac[20]; /* SHA-1 hash len */
- unsigned int hash_len;
- HMAC_CTX ctx;
-
- blob.data = r->in.data_in;
- blob.length = r->in.data_in_len;
-
- if (r->in.data_in_len == 0 || r->in.data_in == NULL) {
- return WERR_INVALID_PARAMETER;
- }
-
- ndr_err = ndr_pull_struct_blob_all(&blob, mem_ctx, &decrypt_request,
- (ndr_pull_flags_fn_t)ndr_pull_bkrp_server_side_wrapped);
- if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
- return WERR_INVALID_PARAMETER;
- }
-
- if (decrypt_request.magic != BACKUPKEY_SERVER_WRAP_VERSION) {
- return WERR_INVALID_PARAMETER;
- }
-
- werr = bkrp_do_retrieve_server_wrap_key(mem_ctx, ldb_ctx, &server_key,
- &decrypt_request.guid);
- if (!W_ERROR_IS_OK(werr)) {
- return werr;
- }
-
- dump_data_pw("server_key: \n", server_key.key, sizeof(server_key.key));
-
- dump_data_pw("r2: \n", decrypt_request.r2, sizeof(decrypt_request.r2));
-
- /*
- * This is *not* the leading 64 bytes, as indicated in MS-BKRP 3.1.4.1.1
- * BACKUPKEY_BACKUP_GUID, it really is the whole key
- */
- HMAC(EVP_sha1(), server_key.key, sizeof(server_key.key),
- decrypt_request.r2, sizeof(decrypt_request.r2),
- symkey, &hash_len);
-
- dump_data_pw("symkey: \n", symkey, hash_len);
-
- /* rc4 decrypt sid and secret using sym key */
- symkey_blob = data_blob_const(symkey, sizeof(symkey));
-
- encrypted_blob = data_blob_const(decrypt_request.rc4encryptedpayload,
- decrypt_request.ciphertext_length);
-
- arcfour_crypt_blob(encrypted_blob.data, encrypted_blob.length, &symkey_blob);
-
- ndr_err = ndr_pull_struct_blob_all(&encrypted_blob, mem_ctx, &rc4payload,
- (ndr_pull_flags_fn_t)ndr_pull_bkrp_rc4encryptedpayload);
- if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
- return WERR_INVALID_PARAMETER;
- }
-
- if (decrypt_request.payload_length != rc4payload.secret_data.length) {
- return WERR_INVALID_PARAMETER;
- }
-
- dump_data_pw("r3: \n", rc4payload.r3, sizeof(rc4payload.r3));
-
- /*
- * This is *not* the leading 64 bytes, as indicated in MS-BKRP 3.1.4.1.1
- * BACKUPKEY_BACKUP_GUID, it really is the whole key
- */
- HMAC(EVP_sha1(), server_key.key, sizeof(server_key.key),
- rc4payload.r3, sizeof(rc4payload.r3),
- mackey, &hash_len);
-
- dump_data_pw("mackey: \n", mackey, sizeof(mackey));
-
- ndr_err = ndr_push_struct_blob(&sid_blob, mem_ctx, &rc4payload.sid,
- (ndr_push_flags_fn_t)ndr_push_dom_sid);
- if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
- return WERR_INTERNAL_ERROR;
- }
-
- HMAC_CTX_init(&ctx);
- HMAC_Init_ex(&ctx, mackey, hash_len, EVP_sha1(), NULL);
- /* SID field */
- HMAC_Update(&ctx, sid_blob.data, sid_blob.length);
- /* Secret field */
- HMAC_Update(&ctx, rc4payload.secret_data.data, rc4payload.secret_data.length);
- HMAC_Final(&ctx, mac, &hash_len);
- HMAC_CTX_cleanup(&ctx);
-
- dump_data_pw("mac: \n", mac, sizeof(mac));
- dump_data_pw("rc4payload.mac: \n", rc4payload.mac, sizeof(rc4payload.mac));
-
- if (memcmp(mac, rc4payload.mac, sizeof(mac)) != 0) {
- return WERR_INVALID_ACCESS;
- }
-
- caller_sid = &session_info->security_token->sids[PRIMARY_USER_SID_INDEX];
-
- if (!dom_sid_equal(&rc4payload.sid, caller_sid)) {
- return WERR_INVALID_ACCESS;
- }
-
- *(r->out.data_out) = rc4payload.secret_data.data;
- *(r->out.data_out_len) = rc4payload.secret_data.length;
-
- return WERR_OK;
-}
-
-/*
- * For BACKUPKEY_RESTORE_GUID we need to check the first 4 bytes to
- * determine what type of restore is wanted.
- *
- * See MS-BKRP 3.1.4.1.4 BACKUPKEY_RESTORE_GUID point 1.
- */
-
-static WERROR bkrp_generic_decrypt_data(struct dcesrv_call_state *dce_call, TALLOC_CTX *mem_ctx,
- struct bkrp_BackupKey *r, struct ldb_context *ldb_ctx)
-{
- if (r->in.data_in_len < 4 || r->in.data_in == NULL) {
- return WERR_INVALID_PARAMETER;
- }
-
- if (IVAL(r->in.data_in, 0) == BACKUPKEY_SERVER_WRAP_VERSION) {
- return bkrp_server_wrap_decrypt_data(dce_call, mem_ctx, r, ldb_ctx);
- }
-
- return bkrp_client_wrap_decrypt_data(dce_call, mem_ctx, r, ldb_ctx);
-}
-
-/*
- * We have some data, such as saved website or IMAP passwords that the
- * client would like to put into the profile on-disk. This needs to
- * be encrypted. This version gives the server the data over the
- * network (protected only by the negotiated transport encryption),
- * and asks that it be encrypted and returned for long-term storage.
- *
- * The data is NOT stored in the LSA, but a key to encrypt the data
- * will be stored. There is only one active encryption key per domain,
- * it is pointed at with G$BCKUPKEY_P in the LSA secrets store.
- *
- * The potentially multiple valid decryptiong keys (and the encryption
- * key) are in turn stored in the LSA secrets store as
- * G$BCKUPKEY_keyGuidString.
- *
- */
-
-static WERROR bkrp_server_wrap_encrypt_data(struct dcesrv_call_state *dce_call, TALLOC_CTX *mem_ctx,
- struct bkrp_BackupKey *r ,struct ldb_context *ldb_ctx)
-{
- struct auth_session_info *session_info =
- dcesrv_call_session_info(dce_call);
- DATA_BLOB sid_blob, encrypted_blob, symkey_blob, server_wrapped_blob;
- WERROR werr;
- struct dom_sid *caller_sid;
- uint8_t symkey[20]; /* SHA-1 hash len */
- uint8_t mackey[20]; /* SHA-1 hash len */
- unsigned int hash_len;
- struct bkrp_rc4encryptedpayload rc4payload;
- HMAC_CTX ctx;
- struct bkrp_dc_serverwrap_key server_key;
- enum ndr_err_code ndr_err;
- struct bkrp_server_side_wrapped server_side_wrapped;
- struct GUID guid;
-
- if (r->in.data_in_len == 0 || r->in.data_in == NULL) {
- return WERR_INVALID_PARAMETER;
- }
-
- werr = bkrp_do_retrieve_default_server_wrap_key(mem_ctx,
- ldb_ctx, &server_key,
- &guid);
-
- if (!W_ERROR_IS_OK(werr)) {
- if (W_ERROR_EQUAL(werr, WERR_FILE_NOT_FOUND)) {
- /* Generate the server wrap key since one wasn't found */
- werr = generate_bkrp_server_wrap_key(mem_ctx,
- ldb_ctx);
- if (!W_ERROR_IS_OK(werr)) {
- return WERR_INVALID_PARAMETER;
- }
- werr = bkrp_do_retrieve_default_server_wrap_key(mem_ctx,
- ldb_ctx,
- &server_key,
- &guid);
-
- if (W_ERROR_EQUAL(werr, WERR_FILE_NOT_FOUND)) {
- /* Ok we really don't manage to get this secret ...*/
- return WERR_FILE_NOT_FOUND;
- }
- } else {
- /* In theory we should NEVER reach this point as it
- should only appear in a rodc server */
- /* we do not have the real secret attribute */
- return WERR_INVALID_PARAMETER;
- }
- }
-
- caller_sid = &session_info->security_token->sids[PRIMARY_USER_SID_INDEX];
-
- dump_data_pw("server_key: \n", server_key.key, sizeof(server_key.key));
-
- /*
- * This is the key derivation step, so that the HMAC and RC4
- * operations over the user-supplied data are not able to
- * disclose the master key. By using random data, the symkey
- * and mackey values are unique for this operation, and
- * discovering these (by reversing the RC4 over the
- * attacker-controlled data) does not return something able to
- * be used to decyrpt the encrypted data of other users
- */
- generate_random_buffer(server_side_wrapped.r2, sizeof(server_side_wrapped.r2));
-
- dump_data_pw("r2: \n", server_side_wrapped.r2, sizeof(server_side_wrapped.r2));
-
- generate_random_buffer(rc4payload.r3, sizeof(rc4payload.r3));
-
- dump_data_pw("r3: \n", rc4payload.r3, sizeof(rc4payload.r3));
-
-
- /*
- * This is *not* the leading 64 bytes, as indicated in MS-BKRP 3.1.4.1.1
- * BACKUPKEY_BACKUP_GUID, it really is the whole key
- */
- HMAC(EVP_sha1(), server_key.key, sizeof(server_key.key),
- server_side_wrapped.r2, sizeof(server_side_wrapped.r2),
- symkey, &hash_len);
-
- dump_data_pw("symkey: \n", symkey, hash_len);
-
- /*
- * This is *not* the leading 64 bytes, as indicated in MS-BKRP 3.1.4.1.1
- * BACKUPKEY_BACKUP_GUID, it really is the whole key
- */
- HMAC(EVP_sha1(), server_key.key, sizeof(server_key.key),
- rc4payload.r3, sizeof(rc4payload.r3),
- mackey, &hash_len);
-
- dump_data_pw("mackey: \n", mackey, sizeof(mackey));
-
- ndr_err = ndr_push_struct_blob(&sid_blob, mem_ctx, caller_sid,
- (ndr_push_flags_fn_t)ndr_push_dom_sid);
- if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
- return WERR_INTERNAL_ERROR;
- }
-
- rc4payload.secret_data.data = r->in.data_in;
- rc4payload.secret_data.length = r->in.data_in_len;
-
- HMAC_CTX_init(&ctx);
- HMAC_Init_ex(&ctx, mackey, 20, EVP_sha1(), NULL);
- /* SID field */
- HMAC_Update(&ctx, sid_blob.data, sid_blob.length);
- /* Secret field */
- HMAC_Update(&ctx, rc4payload.secret_data.data, rc4payload.secret_data.length);
- HMAC_Final(&ctx, rc4payload.mac, &hash_len);
- HMAC_CTX_cleanup(&ctx);
-
- dump_data_pw("rc4payload.mac: \n", rc4payload.mac, sizeof(rc4payload.mac));
-
- rc4payload.sid = *caller_sid;
-
- ndr_err = ndr_push_struct_blob(&encrypted_blob, mem_ctx, &rc4payload,
- (ndr_push_flags_fn_t)ndr_push_bkrp_rc4encryptedpayload);
- if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
- return WERR_INTERNAL_ERROR;
- }
-
- /* rc4 encrypt sid and secret using sym key */
- symkey_blob = data_blob_const(symkey, sizeof(symkey));
- arcfour_crypt_blob(encrypted_blob.data, encrypted_blob.length, &symkey_blob);
-
- /* create server wrap structure */
-
- server_side_wrapped.payload_length = rc4payload.secret_data.length;
- server_side_wrapped.ciphertext_length = encrypted_blob.length;
- server_side_wrapped.guid = guid;
- server_side_wrapped.rc4encryptedpayload = encrypted_blob.data;
-
- ndr_err = ndr_push_struct_blob(&server_wrapped_blob, mem_ctx, &server_side_wrapped,
- (ndr_push_flags_fn_t)ndr_push_bkrp_server_side_wrapped);
- if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
- return WERR_INTERNAL_ERROR;
- }
-
- *(r->out.data_out) = server_wrapped_blob.data;
- *(r->out.data_out_len) = server_wrapped_blob.length;
-
- return WERR_OK;
-}
-
-static WERROR dcesrv_bkrp_BackupKey(struct dcesrv_call_state *dce_call,
- TALLOC_CTX *mem_ctx, struct bkrp_BackupKey *r)
-{
- WERROR error = WERR_INVALID_PARAMETER;
- struct ldb_context *ldb_ctx;
- bool is_rodc;
- const char *addr = "unknown";
- /* At which level we start to add more debug of what is done in the protocol */
- const int debuglevel = 4;
-
- if (DEBUGLVL(debuglevel)) {
- const struct tsocket_address *remote_address;
- remote_address = dcesrv_connection_get_remote_address(dce_call->conn);
- if (tsocket_address_is_inet(remote_address, "ip")) {
- addr = tsocket_address_inet_addr_string(remote_address, mem_ctx);
- W_ERROR_HAVE_NO_MEMORY(addr);
- }
- }
-
- if (lpcfg_server_role(dce_call->conn->dce_ctx->lp_ctx) != ROLE_ACTIVE_DIRECTORY_DC) {
- return WERR_NOT_SUPPORTED;
- }
-
- /*
- * Save the current remote session details so they can used by the
- * audit logging module. This allows the audit logging to report the
- * remote users details, rather than the system users details.
- */
- ldb_ctx = dcesrv_samdb_connect_as_system(mem_ctx, dce_call);
- if (samdb_rodc(ldb_ctx, &is_rodc) != LDB_SUCCESS) {
- talloc_unlink(mem_ctx, ldb_ctx);
- return WERR_INVALID_PARAMETER;
- }
-
- if (!is_rodc) {
- if(strncasecmp(GUID_string(mem_ctx, r->in.guidActionAgent),
- BACKUPKEY_RESTORE_GUID, strlen(BACKUPKEY_RESTORE_GUID)) == 0) {
- DEBUG(debuglevel, ("Client %s requested to decrypt a wrapped secret\n", addr));
- error = bkrp_generic_decrypt_data(dce_call, mem_ctx, r, ldb_ctx);
- }
-
- if (strncasecmp(GUID_string(mem_ctx, r->in.guidActionAgent),
- BACKUPKEY_RETRIEVE_BACKUP_KEY_GUID, strlen(BACKUPKEY_RETRIEVE_BACKUP_KEY_GUID)) == 0) {
- DEBUG(debuglevel, ("Client %s requested certificate for client wrapped secret\n", addr));
- error = bkrp_retrieve_client_wrap_key(dce_call, mem_ctx, r, ldb_ctx);
- }
-
- if (strncasecmp(GUID_string(mem_ctx, r->in.guidActionAgent),
- BACKUPKEY_RESTORE_GUID_WIN2K, strlen(BACKUPKEY_RESTORE_GUID_WIN2K)) == 0) {
- DEBUG(debuglevel, ("Client %s requested to decrypt a server side wrapped secret\n", addr));
- error = bkrp_server_wrap_decrypt_data(dce_call, mem_ctx, r, ldb_ctx);
- }
-
- if (strncasecmp(GUID_string(mem_ctx, r->in.guidActionAgent),
- BACKUPKEY_BACKUP_GUID, strlen(BACKUPKEY_BACKUP_GUID)) == 0) {
- DEBUG(debuglevel, ("Client %s requested a server wrapped secret\n", addr));
- error = bkrp_server_wrap_encrypt_data(dce_call, mem_ctx, r, ldb_ctx);
- }
- }
- /*else: I am a RODC so I don't handle backup key protocol */
-
- talloc_unlink(mem_ctx, ldb_ctx);
- return error;
-}
-
-/* include the generated boilerplate */
-#include "librpc/gen_ndr/ndr_backupkey_s.c"
git.samba.org / samba.git / blobdiff