From d2a0904b915c4f9ffe8ca7f8015ef201dd8b827d Mon Sep 17 00:00:00 2001
From: Andrew Bartlett <abartlet@samba.org>
Date: Wed, 31 Jul 2019 16:37:00 +1200
Subject: [PATCH 108/187] s4-samdb: Remove duplicate encrypted_secrets code
using internal Samba AES
We now rely on GnuTLS 3.4.7 or later.
Signed-off-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Andreas Schneider <asn@samba.org>
(cherry picked from commit 85a1c4973921fdf9412ec56a3ed6a77f3ab84116)
---
.../samdb/ldb_modules/encrypted_secrets.c | 266 +----------------
.../tests/test_encrypted_secrets.c | 278 ------------------
2 files changed, 2 insertions(+), 542 deletions(-)
diff --git a/source4/dsdb/samdb/ldb_modules/encrypted_secrets.c b/source4/dsdb/samdb/ldb_modules/encrypted_secrets.c
index e0932858588..0d46031ec64 100644
--- a/source4/dsdb/samdb/ldb_modules/encrypted_secrets.c
+++ b/source4/dsdb/samdb/ldb_modules/encrypted_secrets.c
@@ -39,22 +39,8 @@
#include "dsdb/samdb/samdb.h"
#include "dsdb/samdb/ldb_modules/util.h"
-/* Build either with GnuTLS crypto or Samba crypto. */
-#ifdef HAVE_GNUTLS_AEAD
- #define BUILD_WITH_GNUTLS_AEAD
-#else /* !HAVE_GNUTLS_AEAD */
- #define BUILD_WITH_SAMBA_AES_GCM
-#endif /* HAVE_GNUTLS_AEAD */
-
-#ifdef BUILD_WITH_GNUTLS_AEAD
- #include <gnutls/gnutls.h>
- #include <gnutls/crypto.h>
-#endif /* BUILD_WITH_GNUTLS_AEAD */
-
-#ifdef BUILD_WITH_SAMBA_AES_GCM
- #include "lib/crypto/aes.h"
- #include "lib/crypto/aes_gcm_128.h"
-#endif /* BUILD_WITH_SAMBA_AES_GCM */
+#include <gnutls/gnutls.h>
+#include <gnutls/crypto.h>
static const char * const secret_attributes[] = {DSDB_SECRET_ATTRIBUTES};
static const size_t num_secret_attributes = ARRAY_SIZE(secret_attributes);
@@ -74,12 +60,10 @@ struct es_data {
* Encryption keys for secret attributes
*/
DATA_BLOB keys[NUMBER_OF_KEYS];
-#ifdef BUILD_WITH_GNUTLS_AEAD
/*
* The gnutls algorithm used to encrypt attributes
*/
int encryption_algorithm;
-#endif /* BUILD_WITH_GNUTLS_AEAD */
};
/*
@@ -262,9 +246,7 @@ static int load_keys(struct ldb_module *module, struct es_data *data)
data->keys[0] = key;
data->encrypt_secrets = true;
-#ifdef BUILD_WITH_GNUTLS_AEAD
data->encryption_algorithm = GNUTLS_CIPHER_AES_128_GCM;
-#endif
TALLOC_FREE(frame);
return LDB_SUCCESS;
@@ -299,7 +281,6 @@ static bool should_encrypt(const struct ldb_message_element *el)
*
* @return Size rounded up to the nearest multiple of block_size
*/
-#ifdef BUILD_WITH_GNUTLS_AEAD
static size_t round_to_block_size(size_t block_size, size_t size)
{
if ((size % block_size) == 0) {
@@ -308,7 +289,6 @@ static size_t round_to_block_size(size_t block_size, size_t size)
return ((int)(size/block_size) + 1) * block_size;
}
}
-#endif /* BUILD_WITH_GNUTLS_AEAD */
/*
* @brief Create an new EncryptedSecret owned by the supplied talloc context.
@@ -375,239 +355,6 @@ static DATA_BLOB makePlainText(TALLOC_CTX *ctx,
return pt;
}
-#ifdef BUILD_WITH_SAMBA_AES_GCM
-/*
- * @brief Encrypt an ldb value using an aead algorithm.
- *
- * This function uses the samba internal implementation to perform the encryption. However
- * the encrypted data and tag are stored in a manner compatible with gnutls,
- * so the gnutls aead functions can be used to decrypt and verify the data.
- *
- * @param err Pointer to an error code, set to:
- * LDB_SUCESS If the value was successfully encrypted
- * LDB_ERR_OPERATIONS_ERROR If there was an error.
- *
- * @param ctx Talloc memory context the will own the memory allocated
- * @param ldb ldb context, to allow logging.
- * @param val The ldb value to encrypt, not altered or freed
- * @param data The context data for this module.
- *
- * @return The encrypted ldb_val, or data_blob_null if there was an error.
- */
-static struct ldb_val samba_encrypt_aead(int *err,
- TALLOC_CTX *ctx,
- struct ldb_context *ldb,
- const struct ldb_val val,
- const struct es_data *data)
-{
- struct aes_gcm_128_context cctx;
- struct EncryptedSecret *es = NULL;
- DATA_BLOB pt = data_blob_null;
- struct ldb_val enc = data_blob_null;
- DATA_BLOB key_blob = data_blob_null;
- int rc;
- TALLOC_CTX *frame = talloc_stackframe();
-
- es = makeEncryptedSecret(ldb, frame);
- if (es == NULL) {
- goto error_exit;
- }
-
- pt = makePlainText(frame, ldb, val);
- if (pt.length == 0) {
- goto error_exit;
- }
-
- /*
- * Set the encryption key
- */
- key_blob = get_key(data);
- if (key_blob.length != AES_BLOCK_SIZE) {
- ldb_asprintf_errstring(ldb,
- "Invalid EncryptedSecrets key size, "
- "expected %u bytes and is %zu bytes\n",
- AES_BLOCK_SIZE,
- key_blob.length);
- goto error_exit;
- }
-
- /*
- * Set the initialisation vector
- */
- {
- uint8_t *iv = talloc_zero_size(frame, AES_GCM_128_IV_SIZE);
- if (iv == NULL) {
- ldb_set_errstring(ldb,
- "Out of memory allocating iv\n");
- goto error_exit;
- }
-
- generate_nonce_buffer(iv, AES_GCM_128_IV_SIZE);
-
- es->iv.length = AES_GCM_128_IV_SIZE;
- es->iv.data = iv;
- }
-
- /*
- * Encrypt the value, and append the GCM digest to the encrypted
- * data so that it can be decrypted and validated by the
- * gnutls aead decryption routines.
- */
- {
- uint8_t *ct = talloc_zero_size(frame, pt.length + AES_BLOCK_SIZE);
- if (ct == NULL) {
- ldb_oom(ldb);
- goto error_exit;
- }
-
- memcpy(ct, pt.data, pt.length);
- es->encrypted.length = pt.length + AES_BLOCK_SIZE;
- es->encrypted.data = ct;
- }
-
- aes_gcm_128_init(&cctx, key_blob.data, es->iv.data);
- aes_gcm_128_updateA(&cctx,
- (uint8_t *)&es->header,
- sizeof(struct EncryptedSecretHeader));
- aes_gcm_128_crypt(&cctx, es->encrypted.data, pt.length);
- aes_gcm_128_updateC(&cctx, es->encrypted.data, pt.length);
- aes_gcm_128_digest(&cctx, &es->encrypted.data[pt.length]);
-
- rc = ndr_push_struct_blob(&enc,
- ctx,
- es,
- (ndr_push_flags_fn_t)
- ndr_push_EncryptedSecret);
- if (!NDR_ERR_CODE_IS_SUCCESS(rc)) {
- ldb_set_errstring(ldb,
- "Unable to ndr push EncryptedSecret\n");
- goto error_exit;
- }
- TALLOC_FREE(frame);
- return enc;
-
-error_exit:
- *err = LDB_ERR_OPERATIONS_ERROR;
- TALLOC_FREE(frame);
- return data_blob_null;
-}
-
-/*
- * @brief Decrypt data encrypted using an aead algorithm.
- *
- * Decrypt the data in ed and insert it into ev. The data was encrypted
- * with the samba aes gcm implementation.
- *
- * @param err Pointer to an error code, set to:
- * LDB_SUCESS If the value was successfully decrypted
- * LDB_ERR_OPERATIONS_ERROR If there was an error.
- *
- * @param ctx Talloc memory context that will own the memory allocated
- * @param ldb ldb context, to allow logging.
- * @param ev The value to be updated with the decrypted data.
- * @param ed The data to decrypt.
- * @param data The context data for this module.
- *
- * @return ev is updated with the unencrypted data.
- */
-static void samba_decrypt_aead(int *err,
- TALLOC_CTX *ctx,
- struct ldb_context *ldb,
- struct EncryptedSecret *es,
- struct PlaintextSecret *ps,
- const struct es_data *data)
-{
- struct aes_gcm_128_context cctx;
- DATA_BLOB pt = data_blob_null;
- DATA_BLOB key_blob = data_blob_null;
- uint8_t sig[AES_BLOCK_SIZE] = {0, };
- int rc;
- int cmp;
- TALLOC_CTX *frame = talloc_stackframe();
-
- /*
- * Set the encryption key
- */
- key_blob = get_key(data);
- if (key_blob.length != AES_BLOCK_SIZE) {
- ldb_asprintf_errstring(ldb,
- "Invalid EncryptedSecrets key size, "
- "expected %u bytes and is %zu bytes\n",
- AES_BLOCK_SIZE,
- key_blob.length);
- goto error_exit;
- }
-
- if (es->iv.length < AES_GCM_128_IV_SIZE) {
- ldb_asprintf_errstring(ldb,
- "Invalid EncryptedSecrets iv size, "
- "expected %u bytes and is %zu bytes\n",
- AES_GCM_128_IV_SIZE,
- es->iv.length);
- goto error_exit;
- }
-
- if (es->encrypted.length < AES_BLOCK_SIZE) {
- ldb_asprintf_errstring(ldb,
- "Invalid EncryptedData size, "
- "expected %u bytes and is %zu bytes\n",
- AES_BLOCK_SIZE,
- es->encrypted.length);
- goto error_exit;
- }
-
- pt.length = es->encrypted.length - AES_BLOCK_SIZE;
- pt.data = talloc_zero_size(ctx, pt.length);
- if (pt.data == NULL) {
- ldb_set_errstring(ldb,
- "Out of memory allocating space for "
- "plain text\n");
- goto error_exit;
- }
- memcpy(pt.data, es->encrypted.data, pt.length);
-
- aes_gcm_128_init(&cctx, key_blob.data, es->iv.data);
- aes_gcm_128_updateA(&cctx,
- (uint8_t *)&es->header,
- sizeof(struct EncryptedSecretHeader));
- aes_gcm_128_updateC(&cctx, pt.data, pt.length);
- aes_gcm_128_crypt(&cctx, pt.data, pt.length);
- aes_gcm_128_digest(&cctx, sig);
-
- /*
- * Check the authentication tag
- */
- cmp = memcmp(&es->encrypted.data[pt.length], sig, AES_BLOCK_SIZE);
- if (cmp != 0) {
- ldb_set_errstring(ldb,
- "Tag does not match, "
- "data corrupted or altered\n");
- goto error_exit;
- }
-
- rc = ndr_pull_struct_blob(&pt,
- ctx,
- ps,
- (ndr_pull_flags_fn_t)
- ndr_pull_PlaintextSecret);
- if(!NDR_ERR_CODE_IS_SUCCESS(rc)) {
- ldb_asprintf_errstring(ldb,
- "Error(%d) unpacking decrypted data, "
- "data possibly corrupted or altered\n",
- rc);
- goto error_exit;
- }
- TALLOC_FREE(frame);
- return;
-
-error_exit:
- *err = LDB_ERR_OPERATIONS_ERROR;
- TALLOC_FREE(frame);
- return;
-}
-#endif /* BUILD_WITH_SAMBA_AES_GCM */
-
-#ifdef BUILD_WITH_GNUTLS_AEAD
/*
* Helper function converts a data blob to a gnutls_datum_t.
@@ -946,7 +693,6 @@ error_exit:
*err = LDB_ERR_OPERATIONS_ERROR;
return;
}
-#endif /* BUILD_WITH_GNUTLS_AEAD */
/*
* @brief Encrypt an attribute value using the default encryption algorithm.
@@ -972,11 +718,7 @@ static struct ldb_val encrypt_value(int *err,
const struct ldb_val val,
const struct es_data *data)
{
-#ifdef BUILD_WITH_GNUTLS_AEAD
return gnutls_encrypt_aead(err, ctx, ldb, val, data);
-#elif defined BUILD_WITH_SAMBA_AES_GCM
- return samba_encrypt_aead(err, ctx, ldb, val, data);
-#endif
}
/*
@@ -1206,11 +948,7 @@ static struct ldb_val decrypt_value(int *err,
*err = LDB_ERR_OPERATIONS_ERROR;
return data_blob_null;
}
-#ifdef BUILD_WITH_GNUTLS_AEAD
gnutls_decrypt_aead(err, frame, ldb, &es, &ps, data);
-#elif defined BUILD_WITH_SAMBA_AES_GCM
- samba_decrypt_aead(err, frame, ldb, &es, &ps, data);
-#endif
if (*err != LDB_SUCCESS) {
TALLOC_FREE(frame);
diff --git a/source4/dsdb/samdb/ldb_modules/tests/test_encrypted_secrets.c b/source4/dsdb/samdb/ldb_modules/tests/test_encrypted_secrets.c
index a33781d703d..b9516815f75 100644
--- a/source4/dsdb/samdb/ldb_modules/tests/test_encrypted_secrets.c
+++ b/source4/dsdb/samdb/ldb_modules/tests/test_encrypted_secrets.c
@@ -336,7 +336,6 @@ static void test_key_file_long_key(void **state)
assert_int_equal(0, data_blob_cmp(&key, &data->keys[0]));
}
-#ifdef HAVE_GNUTLS_AEAD
/*
* Test gnutls_encryption and decryption.
*/
@@ -391,9 +390,7 @@ static void test_gnutls_value_encryption(void **state)
&plain_text));
}
}
-#endif /* HAVE_GNUTLS_AEAD */
-#ifdef HAVE_GNUTLS_AEAD
static void test_gnutls_altered_header(void **state)
{
struct ldbtest_ctx *test_ctx =
@@ -458,9 +455,7 @@ static void test_gnutls_altered_header(void **state)
assert_int_equal(LDB_ERR_OPERATIONS_ERROR, err);
}
}
-#endif /* HAVE_GNUTLS_AEAD */
-#ifdef HAVE_GNUTLS_AEAD
static void test_gnutls_altered_data(void **state)
{
struct ldbtest_ctx *test_ctx =
@@ -525,9 +520,7 @@ static void test_gnutls_altered_data(void **state)
assert_int_equal(LDB_ERR_OPERATIONS_ERROR, err);
}
}
-#endif /* HAVE_GNUTLS_AEAD */
-#ifdef HAVE_GNUTLS_AEAD
static void test_gnutls_altered_iv(void **state)
{
struct ldbtest_ctx *test_ctx =
@@ -592,260 +585,10 @@ static void test_gnutls_altered_iv(void **state)
assert_int_equal(LDB_ERR_OPERATIONS_ERROR, err);
}
}
-#endif /* HAVE_GNUTLS_AEAD */
/*
* Test samba encryption and decryption and decryption.
*/
-#ifndef HAVE_GNUTLS_AEAD
-static void test_samba_value_encryption(void **state)
-{
- struct ldbtest_ctx *test_ctx =
- talloc_get_type_abort(*state, struct ldbtest_ctx);
- struct ldb_val plain_text = data_blob_null;
- struct ldb_val cipher_text = data_blob_null;
- struct EncryptedSecret es;
-
- struct es_data *data = talloc_get_type(
- ldb_module_get_private(test_ctx->module),
- struct es_data);
- int err = LDB_SUCCESS;
- int rc;
-
- plain_text = data_blob_string_const("A text value");
- cipher_text = samba_encrypt_aead(
- &err,
- test_ctx,
- test_ctx->ldb,
- plain_text,
- data);
- assert_int_equal(LDB_SUCCESS, err);
-
- rc = ndr_pull_struct_blob(
- &cipher_text,
- test_ctx,
- &es,
- (ndr_pull_flags_fn_t) ndr_pull_EncryptedSecret);
- assert_true(NDR_ERR_CODE_IS_SUCCESS(rc));
- assert_true(check_header(&es));
-
- {
- struct PlaintextSecret *decrypted =
- talloc_zero(test_ctx, struct PlaintextSecret);
- samba_decrypt_aead(
- &err,
- test_ctx,
- test_ctx->ldb,
- &es,
- decrypted,
- data);
- assert_int_equal(LDB_SUCCESS, err);
- assert_int_equal(
- plain_text.length,
- decrypted->cleartext.length);
- assert_int_equal(0,
- data_blob_cmp(
- &decrypted->cleartext,
- &plain_text));
- }
-
-}
-
-static void test_samba_altered_header(void **state)
-{
- struct ldbtest_ctx *test_ctx =
- talloc_get_type_abort(*state, struct ldbtest_ctx);
- struct ldb_val plain_text = data_blob_null;
- struct ldb_val cipher_text = data_blob_null;
- struct EncryptedSecret es;
-
- struct es_data *data = talloc_get_type(
- ldb_module_get_private(test_ctx->module),
- struct es_data);
- int err = LDB_SUCCESS;
- int rc;
-
- plain_text = data_blob_string_const("A text value");
- cipher_text = samba_encrypt_aead(
- &err,
- test_ctx,
- test_ctx->ldb,
- plain_text,
- data);
- assert_int_equal(LDB_SUCCESS, err);
-
- rc = ndr_pull_struct_blob(
- &cipher_text,
- test_ctx,
- &es,
- (ndr_pull_flags_fn_t) ndr_pull_EncryptedSecret);
- assert_true(NDR_ERR_CODE_IS_SUCCESS(rc));
- assert_true(check_header(&es));
-
- {
- struct PlaintextSecret *decrypted =
- talloc_zero(test_ctx, struct PlaintextSecret);
- samba_decrypt_aead(
- &err,
- test_ctx,
- test_ctx->ldb,
- &es,
- decrypted,
- data);
- assert_int_equal(LDB_SUCCESS, err);
- assert_int_equal(
- plain_text.length,
- decrypted->cleartext.length);
- assert_int_equal(0,
- data_blob_cmp(
- &decrypted->cleartext,
- &plain_text));
- }
- es.header.flags = es.header.flags ^ 0xffffffff;
- {
- struct PlaintextSecret *decrypted =
- talloc_zero(test_ctx, struct PlaintextSecret);
- samba_decrypt_aead(
- &err,
- test_ctx,
- test_ctx->ldb,
- &es,
- decrypted,
- data);
- assert_int_equal(LDB_ERR_OPERATIONS_ERROR, err);
- }
-}
-
-static void test_samba_altered_data(void **state)
-{
- struct ldbtest_ctx *test_ctx =
- talloc_get_type_abort(*state, struct ldbtest_ctx);
- struct ldb_val plain_text = data_blob_null;
- struct ldb_val cipher_text = data_blob_null;
- struct EncryptedSecret es;
-
- struct es_data *data = talloc_get_type(
- ldb_module_get_private(test_ctx->module),
- struct es_data);
- int err = LDB_SUCCESS;
- int rc;
-
- plain_text = data_blob_string_const("A text value");
- cipher_text = samba_encrypt_aead(
- &err,
- test_ctx,
- test_ctx->ldb,
- plain_text,
- data);
- assert_int_equal(LDB_SUCCESS, err);
-
- rc = ndr_pull_struct_blob(
- &cipher_text,
- test_ctx,
- &es,
- (ndr_pull_flags_fn_t) ndr_pull_EncryptedSecret);
- assert_true(NDR_ERR_CODE_IS_SUCCESS(rc));
- assert_true(check_header(&es));
-
- {
- struct PlaintextSecret *decrypted =
- talloc_zero(test_ctx, struct PlaintextSecret);
- samba_decrypt_aead(
- &err,
- test_ctx,
- test_ctx->ldb,
- &es,
- decrypted,
- data);
- assert_int_equal(LDB_SUCCESS, err);
- assert_int_equal(
- plain_text.length,
- decrypted->cleartext.length);
- assert_int_equal(0,
- data_blob_cmp(
- &decrypted->cleartext,
- &plain_text));
- }
- es.encrypted.data[0] = es.encrypted.data[0] ^ 0xff;
- {
- struct PlaintextSecret *decrypted =
- talloc_zero(test_ctx, struct PlaintextSecret);
- samba_decrypt_aead(
- &err,
- test_ctx,
- test_ctx->ldb,
- &es,
- decrypted,
- data);
- assert_int_equal(LDB_ERR_OPERATIONS_ERROR, err);
- }
-}
-
-static void test_samba_altered_iv(void **state)
-{
- struct ldbtest_ctx *test_ctx =
- talloc_get_type_abort(*state, struct ldbtest_ctx);
- struct ldb_val plain_text = data_blob_null;
- struct ldb_val cipher_text = data_blob_null;
- struct EncryptedSecret es;
-
- struct es_data *data = talloc_get_type(
- ldb_module_get_private(test_ctx->module),
- struct es_data);
- int err = LDB_SUCCESS;
- int rc;
-
- plain_text = data_blob_string_const("A text value");
- cipher_text = samba_encrypt_aead(
- &err,
- test_ctx,
- test_ctx->ldb,
- plain_text,
- data);
- assert_int_equal(LDB_SUCCESS, err);
-
- rc = ndr_pull_struct_blob(
- &cipher_text,
- test_ctx,
- &es,
- (ndr_pull_flags_fn_t) ndr_pull_EncryptedSecret);
- assert_true(NDR_ERR_CODE_IS_SUCCESS(rc));
- assert_true(check_header(&es));
-
- {
- struct PlaintextSecret *decrypted =
- talloc_zero(test_ctx, struct PlaintextSecret);
- samba_decrypt_aead(
- &err,
- test_ctx,
- test_ctx->ldb,
- &es,
- decrypted,
- data);
- assert_int_equal(LDB_SUCCESS, err);
- assert_int_equal(
- plain_text.length,
- decrypted->cleartext.length);
- assert_int_equal(0,
- data_blob_cmp(
- &decrypted->cleartext,
- &plain_text));
- }
- es.iv.data[0] = es.iv.data[0] ^ 0xff;
- {
- struct PlaintextSecret *decrypted =
- talloc_zero(test_ctx, struct PlaintextSecret);
- samba_decrypt_aead(
- &err,
- test_ctx,
- test_ctx->ldb,
- &es,
- decrypted,
- data);
- assert_int_equal(LDB_ERR_OPERATIONS_ERROR, err);
- }
-}
-#endif
/*
* Test message encryption.
@@ -1096,9 +839,7 @@ static void test_record_decryption(void **state)
.data = es_keys_blob,
.length = sizeof(es_keys_blob),
},
-#ifdef HAVE_GNUTLS_AEAD
.encryption_algorithm = GNUTLS_CIPHER_AES_128_GCM,
-#endif
};
int err = LDB_SUCCESS;
struct ldb_val dec = decrypt_value(&err, test_ctx, test_ctx->ldb, cipher_text,
@@ -1131,7 +872,6 @@ int main(void) {
test_check_header,
setup,
teardown),
-#ifdef HAVE_GNUTLS_AEAD
cmocka_unit_test_setup_teardown(
test_gnutls_value_encryption,
setup_with_key,
@@ -1148,24 +888,6 @@ int main(void) {
test_gnutls_altered_iv,
setup_with_key,
teardown),
-#else
- cmocka_unit_test_setup_teardown(
- test_samba_value_encryption,
- setup_with_key,
- teardown),
- cmocka_unit_test_setup_teardown(
- test_samba_altered_header,
- setup_with_key,
- teardown),
- cmocka_unit_test_setup_teardown(
- test_samba_altered_data,
- setup_with_key,
- teardown),
- cmocka_unit_test_setup_teardown(
- test_samba_altered_iv,
- setup_with_key,
- teardown),
-#endif /* HAVE_GNUTLS_AEAD */
cmocka_unit_test_setup_teardown(
test_message_encryption_decryption,
setup_with_key,
--
2.23.0