tlv_use_case_trusted_name.c

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/*****************************************************************************
 *   (c) 2025 Ledger SAS.
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *****************************************************************************/
 
#include <stdint.h>
#include <string.h>
#include <ctype.h>
 
#include "os_utils.h"
#include "ox_ec.h"
#include "cx.h"
#include "os_pki.h"
#include "ledger_pki.h"
#include "tlv_use_case_trusted_name.h"
 
// Progressive hash of the received TLVs (except the signature type)
// We will know the correct format to use at reception of the signer_algo tag. We don't try to
// be clever and just calculate all hash until then.
// Performance hit is unnoticeable. Memory footprint is negligeable.
typedef struct multi_hash_ctx_s {
    cx_sha256_t    sha256;
    cx_sha3_t      sha3_256;
    cx_sha3_t      keccak_256;
    cx_ripemd160_t ripemd160;
    cx_sha512_t    sha512;
} multi_hash_ctx_t;
 
// Output of the multi hash after hash finalize
typedef struct multi_hash_finalized_u {
    // Use a union trick to always declare at max size
    union {
        uint8_t _sha256[CX_SHA256_SIZE];
        uint8_t _sha3_256[CX_SHA3_256_SIZE];
        uint8_t _keccak_256[CX_KECCAK_256_SIZE];
        uint8_t _ripemd160[CX_RIPEMD160_SIZE];
        uint8_t _sha512[CX_SHA512_SIZE];
        // Generic access at offset 0
        uint8_t _offset_0;
    };
    buffer_t hash;
} multi_hash_finalized_t;
 
static void init_multi_hash_ctx(multi_hash_ctx_t *hash_ctx)
{
    // Use CX_ASSERT, none of those functions can reasonably fail
    CX_ASSERT(cx_sha256_init_no_throw(&hash_ctx->sha256));
    CX_ASSERT(cx_sha3_init_no_throw(&hash_ctx->sha3_256, CX_SHA3_256_SIZE * 8));
    CX_ASSERT(cx_keccak_init_no_throw(&hash_ctx->keccak_256, CX_KECCAK_256_SIZE * 8));
    CX_ASSERT(cx_ripemd160_init_no_throw(&hash_ctx->ripemd160));
    CX_ASSERT(cx_sha512_init_no_throw(&hash_ctx->sha512));
}
 
// Feed data into all hash without concern
static void update_multi_hash_ctx(multi_hash_ctx_t *hash_ctx, buffer_t data)
{
    // Use CX_ASSERT, none of those functions can reasonably fail
    CX_ASSERT(cx_hash_update((cx_hash_t *) &hash_ctx->sha256, data.ptr, data.size));
    CX_ASSERT(cx_hash_update((cx_hash_t *) &hash_ctx->sha3_256, data.ptr, data.size));
    CX_ASSERT(cx_hash_update((cx_hash_t *) &hash_ctx->keccak_256, data.ptr, data.size));
    CX_ASSERT(cx_hash_update((cx_hash_t *) &hash_ctx->ripemd160, data.ptr, data.size));
    CX_ASSERT(cx_hash_update((cx_hash_t *) &hash_ctx->sha512, data.ptr, data.size));
}
 
// Select the correct hash to use depending on the requested algorithm and finalize it
static int finalize_hash_for_algo(const multi_hash_ctx_t             *hash_ctx,
                                  tlv_trusted_name_signer_algorithm_t signer_algo,
                                  multi_hash_finalized_t             *multi_hash_finalized)
{
    cx_hash_t *hash;
    switch (signer_algo) {
        case TLV_TRUSTED_NAME_SIGNER_ALGORITHM_ECDSA_SHA256:
            hash                            = (cx_hash_t *) &hash_ctx->sha256;
            multi_hash_finalized->hash.size = sizeof(multi_hash_finalized->_sha256);
            break;
        case TLV_TRUSTED_NAME_SIGNER_ALGORITHM_ECDSA_SHA3_256:
        case TLV_TRUSTED_NAME_SIGNER_ALGORITHM_EDDSA_SHA3_256:
            hash                            = (cx_hash_t *) &hash_ctx->sha3_256;
            multi_hash_finalized->hash.size = sizeof(multi_hash_finalized->_sha3_256);
            break;
        case TLV_TRUSTED_NAME_SIGNER_ALGORITHM_ECDSA_KECCAK_256:
        case TLV_TRUSTED_NAME_SIGNER_ALGORITHM_EDDSA_KECCAK_256:
            hash                            = (cx_hash_t *) &hash_ctx->keccak_256;
            multi_hash_finalized->hash.size = sizeof(multi_hash_finalized->_keccak_256);
            break;
        case TLV_TRUSTED_NAME_SIGNER_ALGORITHM_ECDSA_RIPEMD160:
            hash                            = (cx_hash_t *) &hash_ctx->ripemd160;
            multi_hash_finalized->hash.size = sizeof(multi_hash_finalized->_ripemd160);
            break;
        case TLV_TRUSTED_NAME_SIGNER_ALGORITHM_ECDSA_SHA512:
            hash                            = (cx_hash_t *) &hash_ctx->sha512;
            multi_hash_finalized->hash.size = sizeof(multi_hash_finalized->_sha512);
            break;
        default:
            PRINTF("Unknown signer_algo %d\n", signer_algo);
            return -1;
    }
 
    multi_hash_finalized->hash.ptr = &multi_hash_finalized->_offset_0;
    if (cx_hash_final(hash, &multi_hash_finalized->_offset_0) != CX_OK) {
        PRINTF("cx_hash_final failed for algo %d\n", signer_algo);
        return -1;
    }
 
    return 0;
}
 
// Parsed TLV data
typedef struct tlv_extracted_s {
    // Received tags set by the parser
    TLV_reception_t received_tags;
 
    // Trusted name output data
    tlv_trusted_name_out_t *output;
 
    // Tags handled by the use case API and not the caller
    uint8_t  structure_type;
    uint16_t signer_key_id;
    uint8_t  signer_algo;
    buffer_t input_sig;
 
    // Hash using all protocols at once
    multi_hash_ctx_t hash_ctx;
} tlv_extracted_t;
 
static bool handle_structure_type(const tlv_data_t *data, tlv_extracted_t *tlv_extracted)
{
    return get_uint8_t_from_tlv_data(data, &tlv_extracted->structure_type);
}
 
static bool handle_version(const tlv_data_t *data, tlv_extracted_t *tlv_extracted)
{
    return get_uint8_t_from_tlv_data(data, &tlv_extracted->output->version);
}
 
static bool handle_trusted_name_type(const tlv_data_t *data, tlv_extracted_t *tlv_extracted)
{
    return get_uint8_t_from_tlv_data(data, &tlv_extracted->output->trusted_name_type);
}
 
static bool handle_trusted_name_source(const tlv_data_t *data, tlv_extracted_t *tlv_extracted)
{
    return get_uint8_t_from_tlv_data(data, &tlv_extracted->output->trusted_name_source);
}
 
static bool handle_blockchain_family(const tlv_data_t *data, tlv_extracted_t *tlv_extracted)
{
    return get_uint8_t_from_tlv_data(data, &tlv_extracted->output->blockchain_family);
}
 
static bool handle_trusted_name(const tlv_data_t *data, tlv_extracted_t *tlv_extracted)
{
    return get_buffer_from_tlv_data(
        data, &tlv_extracted->output->trusted_name, 1, TRUSTED_NAME_STRINGS_MAX_SIZE);
}
 
static bool handle_chain_id(const tlv_data_t *data, tlv_extracted_t *tlv_extracted)
{
    return get_uint64_t_from_tlv_data(data, &tlv_extracted->output->chain_id);
}
 
static bool handle_address(const tlv_data_t *data, tlv_extracted_t *tlv_extracted)
{
    return get_buffer_from_tlv_data(data, &tlv_extracted->output->address, 1, 0);
}
 
static bool handle_nft_id(const tlv_data_t *data, tlv_extracted_t *tlv_extracted)
{
    return get_buffer_from_tlv_data(data, &tlv_extracted->output->nft_id, NFT_ID_SIZE, NFT_ID_SIZE);
}
 
static bool handle_source_contract(const tlv_data_t *data, tlv_extracted_t *tlv_extracted)
{
    return get_buffer_from_tlv_data(data, &tlv_extracted->output->source_contract, 1, 0);
}
 
static bool handle_challenge(const tlv_data_t *data, tlv_extracted_t *tlv_extracted)
{
    return get_uint32_t_from_tlv_data(data, &tlv_extracted->output->challenge);
}
 
static bool handle_not_valid_after(const tlv_data_t *data, tlv_extracted_t *tlv_extracted)
{
    if (data->value.size != sizeof(tlv_extracted->output->not_valid_after)) {
        PRINTF("Invalid handle_not_valid_after format length %d\n", data->value.size);
        return false;
    }
    tlv_extracted->output->not_valid_after.major = data->value.ptr[0];
    tlv_extracted->output->not_valid_after.minor = data->value.ptr[1];
    tlv_extracted->output->not_valid_after.patch = U2BE(data->value.ptr, 2);
    PRINTF("major = %d minor = %d patch = %d\n",
           tlv_extracted->output->not_valid_after.major,
           tlv_extracted->output->not_valid_after.minor,
           tlv_extracted->output->not_valid_after.patch);
    return true;
}
 
static bool handle_signer_key_id(const tlv_data_t *data, tlv_extracted_t *tlv_extracted)
{
    return get_uint16_t_from_tlv_data(data, &tlv_extracted->signer_key_id);
}
 
static bool handle_signer_algorithm(const tlv_data_t *data, tlv_extracted_t *tlv_extracted)
{
    return get_uint8_t_from_tlv_data(data, &tlv_extracted->signer_algo);
}
 
static bool handle_der_signature(const tlv_data_t *data, tlv_extracted_t *tlv_extracted)
{
    return get_buffer_from_tlv_data(
        data, &tlv_extracted->input_sig, DER_SIGNATURE_MIN_SIZE, DER_SIGNATURE_MAX_SIZE);
}
 
static bool handle_common(const tlv_data_t *data, tlv_extracted_t *tlv_extracted);
 
// clang-format off
// List of TLV tags recognized by the Solana application
#define TLV_TAGS(X)                                                                  \
    X(0x01, TAG_STRUCTURE_TYPE,      handle_structure_type,      ENFORCE_UNIQUE_TAG) \
    X(0x02, TAG_VERSION,             handle_version,             ENFORCE_UNIQUE_TAG) \
    X(0x70, TAG_TRUSTED_NAME_TYPE,   handle_trusted_name_type,   ENFORCE_UNIQUE_TAG) \
    X(0x71, TAG_TRUSTED_NAME_SOURCE, handle_trusted_name_source, ENFORCE_UNIQUE_TAG) \
    X(0x51, TAG_BLOCKCHAIN_FAMILY,   handle_blockchain_family,   ENFORCE_UNIQUE_TAG) \
    X(0x20, TAG_TRUSTED_NAME,        handle_trusted_name,        ENFORCE_UNIQUE_TAG) \
    X(0x23, TAG_CHAIN_ID,            handle_chain_id,            ENFORCE_UNIQUE_TAG) \
    X(0x22, TAG_ADDRESS,             handle_address,             ENFORCE_UNIQUE_TAG) \
    X(0x72, TAG_NFT_ID,              handle_nft_id,              ENFORCE_UNIQUE_TAG) \
    X(0x73, TAG_SOURCE_CONTRACT,     handle_source_contract,     ENFORCE_UNIQUE_TAG) \
    X(0x12, TAG_CHALLENGE,           handle_challenge,           ENFORCE_UNIQUE_TAG) \
    X(0x10, TAG_NOT_VALID_AFTER,     handle_not_valid_after,     ENFORCE_UNIQUE_TAG) \
    X(0x13, TAG_SIGNER_KEY_ID,       handle_signer_key_id,       ENFORCE_UNIQUE_TAG) \
    X(0x14, TAG_SIGNER_ALGORITHM,    handle_signer_algorithm,    ENFORCE_UNIQUE_TAG) \
    X(0x15, TAG_DER_SIGNATURE,       handle_der_signature,       ENFORCE_UNIQUE_TAG)
// clang-format on
 
DEFINE_TLV_PARSER(TLV_TAGS, &handle_common, parse_tlv_trusted_name)
 
static bool handle_common(const tlv_data_t *data, tlv_extracted_t *tlv_extracted)
{
    if (data->tag != TAG_DER_SIGNATURE) {
        update_multi_hash_ctx(&tlv_extracted->hash_ctx, data->raw);
    }
    return true;
}
 
static tlv_trusted_name_status_t verify_struct(const tlv_extracted_t *tlv_extracted)
{
#ifdef TRUSTED_NAME_TEST_KEY
    uint16_t valid_key_id = TLV_TRUSTED_NAME_SIGNER_KEY_ID_TEST;
#else
    uint16_t valid_key_id = TLV_TRUSTED_NAME_SIGNER_KEY_ID_PROD;
#endif
 
    if (!TLV_CHECK_RECEIVED_TAGS(tlv_extracted->received_tags, TAG_STRUCTURE_TYPE)) {
        PRINTF("Error: no struct type specified!\n");
        return TLV_TRUSTED_NAME_MISSING_STRUCTURE_TAG;
    }
 
    if (tlv_extracted->structure_type != TLV_STRUCTURE_TYPE_TRUSTED_NAME) {
        PRINTF("Error: unexpected struct type %d\n", tlv_extracted->structure_type);
        return TLV_TRUSTED_NAME_WRONG_TYPE;
    }
 
    // Check required fields
    if (!TLV_CHECK_RECEIVED_TAGS(tlv_extracted->received_tags,
                                 TAG_VERSION,
                                 TAG_TRUSTED_NAME_TYPE,
                                 TAG_TRUSTED_NAME_SOURCE,
                                 TAG_TRUSTED_NAME,
                                 TAG_CHAIN_ID,
                                 TAG_ADDRESS,
                                 TAG_SIGNER_KEY_ID,
                                 TAG_SIGNER_ALGORITHM,
                                 TAG_DER_SIGNATURE)) {
        PRINTF("Error: missing required fields in struct version %d\n",
               CURRENT_TRUSTED_NAME_SPEC_VERSION);
        return TLV_TRUSTED_NAME_MISSING_TAG;
    }
 
    // Forward optional fields to caller application
    tlv_extracted->output->nft_id_received
        = TLV_CHECK_RECEIVED_TAGS(tlv_extracted->received_tags, TAG_NFT_ID);
    tlv_extracted->output->source_contract_received
        = TLV_CHECK_RECEIVED_TAGS(tlv_extracted->received_tags, TAG_SOURCE_CONTRACT);
    tlv_extracted->output->challenge_received
        = TLV_CHECK_RECEIVED_TAGS(tlv_extracted->received_tags, TAG_CHALLENGE);
    tlv_extracted->output->not_valid_after_received
        = TLV_CHECK_RECEIVED_TAGS(tlv_extracted->received_tags, TAG_NOT_VALID_AFTER);
    tlv_extracted->output->blockchain_family_received
        = TLV_CHECK_RECEIVED_TAGS(tlv_extracted->received_tags, TAG_BLOCKCHAIN_FAMILY);
 
    if (tlv_extracted->output->version == 0
        || tlv_extracted->output->version > CURRENT_TRUSTED_NAME_SPEC_VERSION) {
        PRINTF("Error: unsupported struct version %d\n", tlv_extracted->output->version);
        return TLV_TRUSTED_NAME_UNKNOWN_VERSION;
    }
 
    if (tlv_extracted->output->source_contract_received
        && tlv_extracted->output->version < SOURCE_CONTRACT_RECEIVED_MIN_VERSION) {
        PRINTF("Error: source_contract_received is only supported in v >= %d\n",
               SOURCE_CONTRACT_RECEIVED_MIN_VERSION);
        return TLV_TRUSTED_NAME_UNSUPPORTED_TAG;
    }
 
    if (tlv_extracted->signer_key_id != valid_key_id) {
        PRINTF("Error: wrong metadata key ID %u\n", tlv_extracted->signer_key_id);
        return TLV_TRUSTED_NAME_WRONG_KEY_ID;
    }
 
    return TLV_TRUSTED_NAME_SUCCESS;
}
 
static tlv_trusted_name_status_t verify_signature(const tlv_extracted_t *tlv_extracted)
{
    // Finalize hash object filled by the parser
    multi_hash_finalized_t multi_hash_finalized;
    if (finalize_hash_for_algo(
            &tlv_extracted->hash_ctx, tlv_extracted->signer_algo, &multi_hash_finalized)
        != 0) {
        PRINTF("finalize_hash_for_algo failed\n");
        return TLV_TRUSTED_NAME_HASH_FAILED;
    }
 
    cx_curve_t curve;
    if (tlv_extracted->signer_algo == TLV_TRUSTED_NAME_SIGNER_ALGORITHM_EDDSA_SHA3_256
        || tlv_extracted->signer_algo == TLV_TRUSTED_NAME_SIGNER_ALGORITHM_EDDSA_KECCAK_256) {
        curve = CX_CURVE_Ed25519;
    }
    else {
        // ECDSA
        curve = CX_CURVE_SECP256K1;
    }
 
    // Verify that the signature field of the TLV is the signature of the TLV hash by the key loaded
    // by the PKI
    check_signature_with_pki_status_t err;
    uint8_t expected_key_usage = CERTIFICATE_PUBLIC_KEY_USAGE_TRUSTED_NAME;
    err                        = check_signature_with_pki(
        multi_hash_finalized.hash, &expected_key_usage, &curve, tlv_extracted->input_sig);
    if (err != CHECK_SIGNATURE_WITH_PKI_SUCCESS) {
        PRINTF("Failed to verify signature of trusted token info\n");
        return TLV_TRUSTED_NAME_SIGNATURE_ERROR | err;
    }
 
    return TLV_TRUSTED_NAME_SUCCESS;
}
 
tlv_trusted_name_status_t tlv_use_case_trusted_name(const buffer_t         *payload,
                                                    tlv_trusted_name_out_t *out)
{
    // Main structure that will received the parsed TLV data
    tlv_extracted_t tlv_extracted = {0};
    tlv_extracted.output          = out;
    tlv_trusted_name_status_t err;
 
    // The parser will fill it with the hash of the whole TLV payload (except SIGN tag)
    init_multi_hash_ctx(&tlv_extracted.hash_ctx);
 
    // Call the function created by the macro from the TLV lib
    if (!parse_tlv_trusted_name(payload, &tlv_extracted, &tlv_extracted.received_tags)) {
        PRINTF("Failed to parse tlv payload\n");
        return TLV_TRUSTED_NAME_PARSING_ERROR;
    }
 
    // Verify that the fields received are correct in our context
    err = verify_struct(&tlv_extracted);
    if (err != TLV_TRUSTED_NAME_SUCCESS) {
        PRINTF("Failed to verify tlv payload\n");
        return err;
    }
 
    // Verify that the fields received are correct in our context
    err = verify_signature(&tlv_extracted);
    if (err != TLV_TRUSTED_NAME_SUCCESS) {
        PRINTF("Failed to verify trusted name signature\n");
        return err;
    }
 
    return TLV_TRUSTED_NAME_SUCCESS;
}