/*
 * Type definitions for Group Key Distribution Service
 *
 * The below was initially obtained from MS-GKDI which is copyright © 2021
 * Microsoft Corporation as permitted by the Open Specifications terms
 * reproduced in IDL_LICENCE.txt.
 *
 * Only GetKey() was provided as IDL. The definitions of GroupKeyEnvelope,
 * KdfParameters, and FfcDhParameters were derived from structure diagrams.
 * KeyEnvelope was undocumented.
 */

#include "idl_types.h"

import "misc.idl";

[
  uuid("b9785960-524f-11df-8b6d-83dcded72085"),
  endpoint("ncacn_np:[\\pipe\\lsass]", "ncacn_ip_tcp:", "ncalrpc:"),
  version(1.0),
  pointer_default(unique),
  helpstring("Active Directory Group Key Distribution Service")
]
interface gkdi
{
	/* Public structures. */

	typedef [bitmap32bit] bitmap {
		ENVELOPE_FLAG_TRANSPORTING_PUBLIC_KEY = 0x00000001,
		ENVELOPE_FLAG_KEY_MAY_ENCRYPT_NEW_DATA = 0x00000002
	} EnvelopeFlags;

	/*
	 * This is an undocumented type. It is similar to GroupKeyEnvelope, but
	 * with some fields omitted.
	 */
	typedef [public] struct {
		uint32 version;
		[value(0x4b53444b), range(0x4b53444b, 0x4b53444b)] uint32 magic; /* ‘KDSK’ */
		EnvelopeFlags flags;
		uint32 l0_index;
		[range(0, 31)] uint32 l1_index;
		[range(0, 31)] uint32 l2_index;
		GUID root_key_id;
		uint32 additional_info_len;
		[value(2 * ndr_charset_length(domain_name, CH_UTF16))] uint32 domain_name_len;
		[value(2 * ndr_charset_length(forest_name, CH_UTF16))] uint32 forest_name_len;
		/*
		 * https://lists.samba.org/archive/cifs-protocol/2023-December/004170.html
		 * This is the public key blob of an ephemeral public key used in secret
		 * agreement, or a random number used in deriving a symmetric key.
		 */
		[flag(NDR_SECRET)] uint8 additional_info[additional_info_len];
		nstring domain_name; /* DNS name of the domain which generated the key. */
		nstring forest_name; /* DNS name of the forest which generated the key. */
	} KeyEnvelope;

	typedef [public] struct {
		uint32 version; /* The version (msKds-Version) of the root key ADM element. */
		[value(0x4b53444b), range(0x4b53444b, 0x4b53444b)] uint32 magic; /* ‘KDSK’ */
		EnvelopeFlags flags;
		uint32 l0_index;
		[range(0, 31)] uint32 l1_index;
		[range(0, 31)] uint32 l2_index;
		GUID root_key_id;
		[value(2 * ndr_charset_length(kdf_algorithm, CH_UTF16))] uint32 kdf_algorithm_len;
		uint32 kdf_parameters_len;
		[value(2 * ndr_charset_length(secret_agreement_algorithm, CH_UTF16))] uint32 secret_agreement_algorithm_len;
		uint32 secret_agreement_parameters_len;
		uint32 private_key_len;
		uint32 public_key_len;
		uint32 l1_key_len;
		uint32 l2_key_len;
		[value(2 * ndr_charset_length(domain_name, CH_UTF16))] uint32 domain_name_len;
		[value(2 * ndr_charset_length(forest_name, CH_UTF16))] uint32 forest_name_len;
		nstring kdf_algorithm;
		uint8 kdf_parameters[kdf_parameters_len];
		nstring secret_agreement_algorithm;
		uint8 secret_agreement_parameters[secret_agreement_parameters_len];
		nstring domain_name; /* DNS name of the domain which generated the key. */
		nstring forest_name; /* DNS name of the forest which generated the key. */
		[flag(NDR_SECRET)] uint8 l1_key[l1_key_len];
		[flag(NDR_SECRET)] uint8 l2_key[l2_key_len];
	} GroupKeyEnvelope;

	typedef [public] struct {
		[value(0)] uint32 padding_0;
		[value(1)] uint32 padding_1;
		[value(2 * ndr_charset_length(hash_algorithm, CH_UTF16))] uint32 hash_algorithm_len;
		[value(0)] uint32 padding_2;
		nstring hash_algorithm;
	} KdfParameters;

	typedef [public] struct {
		/*
		 * Twelve bytes account for the length, magic number, and key
		 * length; the remaining bytes cover the two arrays of
		 * ‘key_length’ bytes each.
		 */
		[value(12 + 2 * key_length)] uint32 length;
		[value(0x4d504844), range(0x4d504844, 0x4d504844)] uint32 magic; /* ‘DHPM’ */
		uint32 key_length;
		uint8 field_order[key_length];
		uint8 generator[key_length];
	} FfcDhParameters;

	typedef [public] struct {
		GUID guid;
		int32 l0_idx;
		int32 l1_idx;
		int32 l2_idx;
		[flag(NDR_REMAINING)] DATA_BLOB target_security_descriptor;
	} GkdiDerivationCtx;

	HRESULT gkdi_GetKey(
		[in] uint32 target_sd_len,
		[in] [size_is(target_sd_len)] [ref] char *target_sd,
		[in] [unique] GUID* root_key_id,
		[in] int32 l0_key_id,
		[in] int32 l1_key_id,
		[in] int32 l2_key_id,
		[out] uint32 *out_len,
		[out] [size_is(,*out_len)] uint8** out
	);
}