ledger_account_provide_contact.c

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/*****************************************************************************
 *   (c) 2026 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.
 *****************************************************************************/
 
/* Includes ------------------------------------------------------------------*/
#include <string.h>
#include "os_utils.h"
#include "status_words.h"
#include "tlv_library.h"
#include "buffer.h"
#include "bip32.h"
#include "address_book.h"
#include "address_book_entrypoints.h"
#include "address_book_crypto.h"
#include "address_book_common.h"
#include "ledger_account.h"
 
#if defined(HAVE_ADDRESS_BOOK) && defined(HAVE_ADDRESS_BOOK_LEDGER_ACCOUNT)
 
/* Private defines------------------------------------------------------------*/
#define STRUCT_VERSION 0x01
 
/* Private types, structures, unions -----------------------------------------*/
typedef struct {
    ledger_account_t *ledger_account;
    TLV_reception_t   received_tags;
    uint8_t           hmac_proof[CX_SHA256_SIZE];
} s_provide_ledger_account_ctx;
 
/* Private macros-------------------------------------------------------------*/
#define PROVIDE_LEDGER_ACCOUNT_TAGS(X)                                           \
    X(0x01, TAG_STRUCTURE_TYPE, handle_struct_type, ENFORCE_UNIQUE_TAG)          \
    X(0x02, TAG_STRUCTURE_VERSION, handle_struct_version, ENFORCE_UNIQUE_TAG)    \
    X(0xf0, TAG_CONTACT_NAME, handle_contact_name, ENFORCE_UNIQUE_TAG)           \
    X(0x21, TAG_DERIVATION_PATH, handle_derivation_path, ENFORCE_UNIQUE_TAG)     \
    X(0x23, TAG_CHAIN_ID, handle_chain_id, ENFORCE_UNIQUE_TAG)                   \
    X(0x51, TAG_BLOCKCHAIN_FAMILY, handle_blockchain_family, ENFORCE_UNIQUE_TAG) \
    X(0x29, TAG_HMAC_PROOF, handle_hmac_proof, ENFORCE_UNIQUE_TAG)
 
/* Private variables ---------------------------------------------------------*/
 
/* Private functions ---------------------------------------------------------*/
 
static bool handle_struct_type(const tlv_data_t *data, s_provide_ledger_account_ctx *context)
{
    UNUSED(context);
    if (!tlv_enforce_u8_value(data, TYPE_PROVIDE_LEDGER_ACCOUNT_CONTACT)) {
        PRINTF("[Provide Ledger Account] Invalid STRUCTURE_TYPE value\n");
        return false;
    }
    return true;
}
 
static bool handle_struct_version(const tlv_data_t *data, s_provide_ledger_account_ctx *context)
{
    UNUSED(context);
    if (!tlv_enforce_u8_value(data, STRUCT_VERSION)) {
        PRINTF("[Provide Ledger Account] Invalid STRUCTURE_VERSION value\n");
        return false;
    }
    return true;
}
 
static bool handle_contact_name(const tlv_data_t *data, s_provide_ledger_account_ctx *context)
{
    if (!address_book_handle_printable_string(data,
                                              context->ledger_account->account_name,
                                              sizeof(context->ledger_account->account_name))) {
        PRINTF("[Provide Ledger Account] CONTACT_NAME: failed to parse\n");
        return false;
    }
    return true;
}
 
static bool handle_derivation_path(const tlv_data_t *data, s_provide_ledger_account_ctx *context)
{
    return address_book_handle_derivation_path(data, &context->ledger_account->bip32_path);
}
 
static bool handle_chain_id(const tlv_data_t *data, s_provide_ledger_account_ctx *context)
{
    return address_book_handle_chain_id(data, &context->ledger_account->chain_id);
}
 
static bool handle_blockchain_family(const tlv_data_t *data, s_provide_ledger_account_ctx *context)
{
    return address_book_handle_blockchain_family(data, &context->ledger_account->blockchain_family);
}
 
static bool handle_hmac_proof(const tlv_data_t *data, s_provide_ledger_account_ctx *context)
{
    buffer_t buf = {0};
    if (!get_buffer_from_tlv_data(data, &buf, CX_SHA256_SIZE, CX_SHA256_SIZE)) {
        PRINTF("[Provide Ledger Account] HMAC_PROOF: invalid length (expected %d bytes)\n",
               CX_SHA256_SIZE);
        return false;
    }
    memmove(context->hmac_proof, buf.ptr, CX_SHA256_SIZE);
    return true;
}
 
DEFINE_TLV_PARSER(PROVIDE_LEDGER_ACCOUNT_TAGS, NULL, provide_ledger_account_tlv_parser)
 
 
static bool verify_fields(const s_provide_ledger_account_ctx *context)
{
    bool result = TLV_CHECK_RECEIVED_TAGS(context->received_tags,
                                          TAG_STRUCTURE_TYPE,
                                          TAG_STRUCTURE_VERSION,
                                          TAG_CONTACT_NAME,
                                          TAG_DERIVATION_PATH,
                                          TAG_BLOCKCHAIN_FAMILY,
                                          TAG_HMAC_PROOF);
    if (!result) {
        PRINTF("[Provide Ledger Account] Missing mandatory fields!\n");
        return false;
    }
    if (context->ledger_account->blockchain_family == FAMILY_ETHEREUM) {
        result = TLV_CHECK_RECEIVED_TAGS(context->received_tags, TAG_CHAIN_ID);
        if (!result) {
            PRINTF("[Provide Ledger Account] Missing CHAIN_ID for Ethereum family!\n");
            return false;
        }
    }
    return true;
}
 
static void print_payload(const s_provide_ledger_account_ctx *context)
{
    UNUSED(context);
    char out[50] = {0};
 
    PRINTF("****************************************************************************\n");
    PRINTF("[Provide Ledger Account] - Retrieved Descriptor:\n");
    PRINTF("[Provide Ledger Account] -    Account name:        %s\n",
           context->ledger_account->account_name);
    if (bip32_path_format_simple(&context->ledger_account->bip32_path, out, sizeof(out))) {
        PRINTF("[Provide Ledger Account] -    Derivation path[%d]: %s\n",
               context->ledger_account->bip32_path.length,
               out);
    }
    else {
        PRINTF("[Provide Ledger Account] -    Derivation path length[%d] (failed to format)\n",
               context->ledger_account->bip32_path.length);
    }
    PRINTF("[Provide Ledger Account] -    Blockchain family:   %s\n",
           FAMILY_AS_STR(context->ledger_account->blockchain_family));
    if (context->ledger_account->blockchain_family == FAMILY_ETHEREUM) {
        PRINTF("[Provide Ledger Account] -    Chain ID:            %llu\n",
               context->ledger_account->chain_id);
    }
}
 
/* Exported functions --------------------------------------------------------*/
 
bolos_err_t provide_ledger_account_contact(uint8_t *buffer_in, size_t buffer_in_length)
{
    const buffer_t               payload = {.ptr = buffer_in, .size = buffer_in_length};
    s_provide_ledger_account_ctx ctx     = {0};
 
    // Init the structure
    ctx.ledger_account = &g_ab_payload.ledger_account;
    memset(&g_ab_payload.ledger_account, 0, sizeof(g_ab_payload.ledger_account));
 
    // Parse using SDK TLV parser
    if (!provide_ledger_account_tlv_parser(&payload, &ctx, &ctx.received_tags)) {
        PRINTF("[Provide Ledger Account] TLV parsing failed\n");
        return SWO_INCORRECT_DATA;
    }
    if (!verify_fields(&ctx)) {
        return SWO_INCORRECT_DATA;
    }
    print_payload(&ctx);
 
    // Verify HMAC Proof of Registration: HMAC(bip32_path, account_name, family, chain_id)
    if (!address_book_verify_hmac_proof_ledger_account(
            &g_ab_payload.ledger_account.bip32_path,
            g_ab_payload.ledger_account.account_name,
            g_ab_payload.ledger_account.blockchain_family,
            g_ab_payload.ledger_account.chain_id,
            ctx.hmac_proof)) {
        PRINTF("[Provide Ledger Account] HMAC proof verification failed\n");
        return SWO_SECURITY_CONDITION_NOT_SATISFIED;
    }
 
    // Pass verified contact to the coin app for storage
    if (!handle_provide_ledger_account(&g_ab_payload.ledger_account)) {
        PRINTF("[Provide Ledger Account] Rejected by coin application\n");
        return SWO_WRONG_PARAMETER_VALUE;
    }
 
    return SWO_SUCCESS;
}
 
#endif  // HAVE_ADDRESS_BOOK && HAVE_ADDRESS_BOOK_LEDGER_ACCOUNT