diff options
Diffstat (limited to 'source4/dsdb/repl')
| -rw-r--r-- | source4/dsdb/repl/replicated_objects.c | 133 |
1 files changed, 132 insertions, 1 deletions
diff --git a/source4/dsdb/repl/replicated_objects.c b/source4/dsdb/repl/replicated_objects.c index 08a349d1c3..2184f32567 100644 --- a/source4/dsdb/repl/replicated_objects.c +++ b/source4/dsdb/repl/replicated_objects.c @@ -27,11 +27,138 @@ #include "librpc/gen_ndr/ndr_misc.h" #include "librpc/gen_ndr/ndr_drsuapi.h" #include "librpc/gen_ndr/ndr_drsblobs.h" +#include "lib/crypto/crypto.h" + +static WERROR dsdb_decrypt_attribute_value(TALLOC_CTX *mem_ctx, + const DATA_BLOB *gensec_skey, + DATA_BLOB *in, + DATA_BLOB *out) +{ + DATA_BLOB confounder; + DATA_BLOB enc_buffer; + + struct MD5Context md5; + uint8_t _enc_key[16]; + DATA_BLOB enc_key; + + DATA_BLOB dec_buffer; + + uint32_t crc32_given; + uint32_t crc32_calc; + DATA_BLOB checked_buffer; + + DATA_BLOB plain_buffer; + + /* + * the first 16 bytes at the beginning are the confounder + * followed by the 4 byte crc32 checksum + */ + if (in->length < 20) { + return WERR_DS_DRA_INVALID_PARAMETER; + } + confounder = data_blob_const(in->data, 16); + enc_buffer = data_blob_const(in->data + 16, in->length - 16); + + /* + * build the encryption key md5 over the session key followed + * by the confounder + * + * here the gensec session key is used and + * not the dcerpc ncacn_ip_tcp "SystemLibraryDTC" key! + */ + enc_key = data_blob_const(_enc_key, sizeof(_enc_key)); + MD5Init(&md5); + MD5Update(&md5, gensec_skey->data, gensec_skey->length); + MD5Update(&md5, confounder.data, confounder.length); + MD5Final(enc_key.data, &md5); + + /* + * copy the encrypted buffer part and + * decrypt it using the created encryption key using arcfour + */ + dec_buffer = data_blob_const(enc_buffer.data, enc_buffer.length); + arcfour_crypt_blob(dec_buffer.data, dec_buffer.length, &enc_key); + + /* + * the first 4 byte are the crc32 checksum + * of the remaining bytes + */ + crc32_given = IVAL(dec_buffer.data, 0); + crc32_calc = crc32_calc_buffer(dec_buffer.data + 4 , dec_buffer.length - 4); + if (crc32_given != crc32_calc) { + return WERR_SEC_E_DECRYPT_FAILURE; + } + checked_buffer = data_blob_const(dec_buffer.data + 4, dec_buffer.length - 4); + + if (checked_buffer.length) { + plain_buffer = data_blob_talloc(mem_ctx, checked_buffer.data, checked_buffer.length); + memset(checked_buffer.data, 0x00, checked_buffer.length); + W_ERROR_HAVE_NO_MEMORY(plain_buffer.data); + } else { + plain_buffer = data_blob_const(NULL, 0); + } + + *out = plain_buffer; + return WERR_OK; +} + +static WERROR dsdb_decrypt_attribute(const DATA_BLOB *gensec_skey, + struct drsuapi_DsReplicaAttribute *attr) +{ + WERROR status; + TALLOC_CTX *mem_ctx; + DATA_BLOB *enc_data; + DATA_BLOB plain_data; + + if (attr->value_ctr.num_values == 0) { + return WERR_OK; + } + + switch (attr->attid) { + case DRSUAPI_ATTRIBUTE_dBCSPwd: + case DRSUAPI_ATTRIBUTE_unicodePwd: + case DRSUAPI_ATTRIBUTE_ntPwdHistory: + case DRSUAPI_ATTRIBUTE_lmPwdHistory: + case DRSUAPI_ATTRIBUTE_supplementalCredentials: + case DRSUAPI_ATTRIBUTE_priorValue: + case DRSUAPI_ATTRIBUTE_currentValue: + case DRSUAPI_ATTRIBUTE_trustAuthOutgoing: + case DRSUAPI_ATTRIBUTE_trustAuthIncoming: + case DRSUAPI_ATTRIBUTE_initialAuthOutgoing: + case DRSUAPI_ATTRIBUTE_initialAuthIncoming: + break; + default: + return WERR_OK; + } + + if (attr->value_ctr.num_values > 1) { + return WERR_DS_DRA_INVALID_PARAMETER; + } + + if (!attr->value_ctr.values[0].blob) { + return WERR_DS_DRA_INVALID_PARAMETER; + } + + mem_ctx = attr->value_ctr.values[0].blob; + enc_data = attr->value_ctr.values[0].blob; + + status = dsdb_decrypt_attribute_value(mem_ctx, + gensec_skey, + enc_data, + &plain_data); + W_ERROR_NOT_OK_RETURN(status); + + talloc_free(attr->value_ctr.values[0].blob->data); + *attr->value_ctr.values[0].blob = plain_data; + + return WERR_OK; +} static WERROR dsdb_convert_object(struct ldb_context *ldb, const struct dsdb_schema *schema, struct dsdb_extended_replicated_objects *ctr, const struct drsuapi_DsReplicaObjectListItemEx *in, + const DATA_BLOB *gensec_skey, TALLOC_CTX *mem_ctx, struct dsdb_extended_replicated_object *out) { @@ -111,6 +238,9 @@ static WERROR dsdb_convert_object(struct ldb_context *ldb, m = &md->ctr.ctr1.array[i]; e = &msg->elements[i]; + status = dsdb_decrypt_attribute(gensec_skey, a); + W_ERROR_NOT_OK_RETURN(status); + status = dsdb_attribute_drsuapi_to_ldb(schema, a, msg->elements, e); W_ERROR_NOT_OK_RETURN(status); @@ -174,6 +304,7 @@ WERROR dsdb_extended_replicated_objects_commit(struct ldb_context *ldb, const struct drsuapi_DsReplicaLinkedAttribute *linked_attributes, const struct repsFromTo1 *source_dsa, const struct drsuapi_DsReplicaCursor2CtrEx *uptodateness_vector, + const DATA_BLOB *gensec_skey, TALLOC_CTX *mem_ctx, struct dsdb_extended_replicated_objects **_out) { @@ -214,7 +345,7 @@ WERROR dsdb_extended_replicated_objects_commit(struct ldb_context *ldb, return WERR_FOOBAR; } - status = dsdb_convert_object(ldb, schema, out, cur, out->objects, &out->objects[i]); + status = dsdb_convert_object(ldb, schema, out, cur, gensec_skey, out->objects, &out->objects[i]); W_ERROR_NOT_OK_RETURN(status); } if (i != out->num_objects) { |