esp-idf: [TW#26741] BLE generating and resolving random mac addresses does not work correctly (IDFGH-10752)

@Weijian-Espressif Most likely there is easier way to do it or more elegant, but this is my address generator. Maybe its not pretty but i think it works just like i expecting:

void BLEAdvertising::setPrivateAddress(esp_ble_addr_type_t type) {
	esp_bd_addr_t addr;
	m_advParams.own_addr_type = type;

	if(type == BLE_ADDR_TYPE_RPA_PUBLIC) {
		esp_ble_gap_config_local_privacy(true);
		return;
	}
	else{
		mbedtls_ctr_drbg_context ctr_drbg;
		mbedtls_entropy_context entropy;
		mbedtls_md_context_t ctx;

		char pers[] = "aes generate key";
		int ret;
		unsigned char key[BLOCK_SIZE] = {0};
		const char inp[] = "random static address";
		unsigned char outp[BLOCK_SIZE/2];

		mbedtls_entropy_init( &entropy );
		mbedtls_ctr_drbg_init( &ctr_drbg );

		if( ( ret = mbedtls_ctr_drbg_seed( &ctr_drbg, mbedtls_entropy_func, &entropy,
			(unsigned char *) pers, strlen( pers ) ) ) != 0 )
		{
			printf( " failed\n ! mbedtls_ctr_drbg_init returned -0x%04x\n", -ret );
			goto exit;
		}

		if( ( ret = mbedtls_ctr_drbg_random( &ctr_drbg, key, BLOCK_SIZE ) ) != 0 )
		{
			printf( " failed\n ! mbedtls_ctr_drbg_random returned -0x%04x\n", -ret );
			goto exit;
		}

		mbedtls_md_init(&ctx);
		mbedtls_md_setup(&ctx, mbedtls_md_info_from_type(HMAC), true);
		mbedtls_md_hmac_starts(&ctx, (const unsigned char *)key, BLOCK_SIZE);
		mbedtls_md_hmac_update(&ctx, (const unsigned char *)inp, strlen(inp));
		mbedtls_md_hmac_finish(&ctx, outp);
		mbedtls_md_free(&ctx);
		ESP_LOG_BUFFER_HEX("random key", key, BLOCK_SIZE);
		ESP_LOG_BUFFER_HEX("HASH step 2", outp, BLOCK_SIZE/2);

		memcpy(addr, outp, 6);
	}
	if(type == BLE_ADDR_TYPE_RANDOM) {
		addr[0] &= 0x3F;  // <--- Format of non-resolvable private address 00xx xxxx
	}
	else{
		addr[0] |= 0xC0;  // <--- Format of static address 11xx xxxx
	}

	esp_ble_gap_set_rand_addr(addr);
	ESP_LOG_BUFFER_HEX("random address", addr, 6);
	exit:
	return;
}

@chegewara esp_ble_gap_set_rand_addr can set random address.

1. BLE_ADDR_TYPE_PUBLIC use public address
2. BLE_ADDR_TYPE_RANDOM use static random address, if not exist, use resolvable address, Otherwise report error
3. BLE_ADDR_TYPE_RPA_RANDOM use resolvable address, if not exist, use random address, Otherwise report error
4. BLE_ADDR_TYPE_RPA_PUBLIC use resolvable address, if not exist, use public address

you can set adv param or scan param to switch address.

btw your time is not wasted, now i ca help other users answering their questions:

https://www.esp32.com/viewtopic.php?f=13&t=7657