ESP32 AES ハードウェアアクセラレータArduinoIDEから使えるようにしてみたが‥

 先日、SHAのアクセラレータが使えるようになりましたので、AESも試してみました。

ただし、Serial.printなどを追記すると、レジスタの出力が反映されていないなどの不具合も含みます。

↓

とりあえず不具合を修正したバージョンが出来上がりました

スケッチ

	#define DPORT_PERI_CLK_EN_REG *((volatile uint32_t *)0x3FF0001C)
	#define DPORT_PERI_RST_EN_REG *((volatile uint32_t *)0x3FF00020)
	#define AES_MODE_REG *((volatile uint32_t *)0x3FF01008)
	#define AES_ENDIAN_REG *((volatile uint32_t *)0x3FF01040)
	#define AES_KEY_0_REG *((volatile uint32_t *)0x3FF01010)
	#define AES_KEY_1_REG *((volatile uint32_t *)0x3FF01014)
	#define AES_KEY_2_REG *((volatile uint32_t *)0x3FF01018)
	#define AES_KEY_3_REG *((volatile uint32_t *)0x3FF0101C)
	#define AES_KEY_4_REG *((volatile uint32_t *)0x3FF01020)
	#define AES_KEY_5_REG *((volatile uint32_t *)0x3FF01024)
	#define AES_KEY_6_REG *((volatile uint32_t *)0x3FF01028)
	#define AES_KEY_7_REG *((volatile uint32_t *)0x3FF0102C)
	#define AES_TEXT_0_REG *((volatile uint32_t *)0x3FF01030)
	#define AES_TEXT_1_REG *((volatile uint32_t *)0x3FF01034)
	#define AES_TEXT_2_REG *((volatile uint32_t *)0x3FF01038)
	#define AES_TEXT_3_REG *((volatile uint32_t *)0x3FF0103C)
	#define AES_START_REG *((volatile uint32_t *)0x3FF01000)
	#define AES_IDLE_REG *((volatile uint32_t *)0x3FF01004)
	#define AES_MODE_AES128ENCRYPTION 0x00000000
	#define AES_MODE_AES192ENCRYPTION 0x00000001
	#define AES_MODE_AES256ENCRYPTION 0x00000002
	#define AES_MODE_AES128DECRYPTION 0x00000004
	#define AES_MODE_AES192DECRYPTION 0x00000005
	#define AES_MODE_AES256DECRYPTION 0x00000006
	#define AES_KEY_ENDIAN0 0x00000000
	#define AES_KEY_ENDIAN1 0x00000001
	#define AES_KEY_ENDIAN2 0x00000002
	#define AES_KEY_ENDIAN3 0x00000003
	#define AES_TEXT_ENDIAN0 0x00000000
	#define AES_TEXT_ENDIAN1 0x00000014
	#define AES_TEXT_ENDIAN2 0x00000028
	#define AES_TEXT_ENDIAN3 0x0000003C
	void setup() {
	uint32_t encrypt_text[4];
	uint32_t decrypt_text[4];
	Serial.begin(115200);
	delay(1000);
	uint32_t plane_text[] = {0x3243f6a8, 0x885a308d, 0x313198a2, 0xe0370734};
	uint32_t cipher_key[] = {0x2b7e1516, 0x28aed2a6, 0xabf71588, 0x09cf4f3c};
	uint32_t crypto_sample_text[] = {0x3925841d, 0x02dc09fb, 0xdc118597, 0x196a0b32};
	//Enable AES module
	DPORT_PERI_CLK_EN_REG = DPORT_PERI_CLK_EN_REG | 0x00000001; // peripheral clock enable
	DPORT_PERI_RST_EN_REG = DPORT_PERI_RST_EN_REG & (~(0x00000001 | 0x00000008 | 0x00000010)); // peripheral reset
	Serial.println("encrypt");
	//1. Initialize AES_MODE_REG, AES_KEY_n_REG, AES_TEXT_m_REG and AES_ENDIAN_REG.
	AES_MODE_REG = AES_MODE_AES128ENCRYPTION;
	AES_ENDIAN_REG = AES_KEY_ENDIAN2 | AES_TEXT_ENDIAN2;
	AES_KEY_0_REG = cipher_key[0];
	AES_KEY_1_REG = cipher_key[1];
	AES_KEY_2_REG = cipher_key[2];
	AES_KEY_3_REG = cipher_key[3];
	AES_TEXT_0_REG = plane_text[0];
	AES_TEXT_1_REG = plane_text[1];
	AES_TEXT_2_REG = plane_text[2];
	AES_TEXT_3_REG = plane_text[3];
	//2. Write 1 to AES_START_REG.
	AES_START_REG = 0x00000001;
	//3. Wait until AES_IDLE_REG reads 1.
	while (AES_IDLE_REG) {}
	while (AES_IDLE_REG) {}
	//4. Read results from AES_TEXT_m_REG
	encrypt_text[0] = AES_TEXT_0_REG;
	encrypt_text[1] = AES_TEXT_1_REG;
	encrypt_text[2] = AES_TEXT_2_REG;
	encrypt_text[3] = AES_TEXT_3_REG;
	//Serial.println("encrypt");
	Serial.print("ENC : ");
	showText(encrypt_text);
	Serial.print("SAMPL: ");
	showText(crypto_sample_text);
	//DeCypher
	Serial.println("decrypt");
	AES_MODE_REG = AES_MODE_AES128DECRYPTION;
	AES_ENDIAN_REG = AES_KEY_ENDIAN2 | AES_TEXT_ENDIAN2;
	AES_TEXT_0_REG = crypto_sample_text[0];
	AES_TEXT_1_REG = crypto_sample_text[1];
	AES_TEXT_2_REG = crypto_sample_text[2];
	AES_TEXT_3_REG = crypto_sample_text[3];
	AES_KEY_0_REG = cipher_key[0];
	AES_KEY_1_REG = cipher_key[1];
	AES_KEY_2_REG = cipher_key[2];
	AES_KEY_3_REG = cipher_key[3];
	AES_START_REG = 0x00000001;
	while (AES_IDLE_REG) {}
	decrypt_text[0] = AES_TEXT_0_REG;
	decrypt_text[1] = AES_TEXT_1_REG;
	decrypt_text[2] = AES_TEXT_2_REG;
	decrypt_text[3] = AES_TEXT_3_REG;
	Serial.print("DEC : ");
	showText(decrypt_text);
	Serial.print("SAMPL: ");
	showText(plane_text);
	//Disable SHA module
	DPORT_PERI_CLK_EN_REG = 0x00000000; // peripheral clock enable
	DPORT_PERI_RST_EN_REG = 0x0000000F; // peripheral reset
	}
	void loop() {
	// put your main code here, to run repeatedly:
	}
	void showText(uint32_t * text) {
	for (int i = 0; i < 4; i++)
	{
	char str[10];
	sprintf(str, "%08x ", text[i]);
	Serial.print(str);
	}
	Serial.println();
	}

view raw ESP32EAESHardwareAcceleratorTest.ino hosted with ❤ by GitHub

結果

encrypt
ENC  : 3925841d 02dc09fb dc118597 196a0b32 
SAMPL: 3925841d 02dc09fb dc118597 196a0b32 
decrypt
DEC  : 3243f6a8 885a308d 313198a2 e0370734 
SAMPL: 3243f6a8 885a308d 313198a2 e0370734 

いちおう動いてはいますが、最初に書いたとおり余計な記述を追加するとAES_TEXT_0_REGの値が実行前のままだったりするので注意が必要です。