[F24:CRYPTO] Add example using cryptographic module on F41x or F2x

2013-12-15 21:47:56 +01:00
parent d8757ab1fc
commit 314ad2d877
4 changed files with 188 additions and 0 deletions
--- a/examples/stm32/f4/other/crypto-basic/cryptobasic.c
+++ b/examples/stm32/f4/other/crypto-basic/cryptobasic.c
@@ -0,0 +1,125 @@
+/*
+ * This file is part of the libopencm3 project.
+ *
+ * Copyright (C) 2009 Uwe Hermann <uwe@hermann-uwe.de>
+ * Copyright (C) 2011 Stephen Caudle <scaudle@doceme.com>
+ *
+ * This library is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <libopencm3/stm32/rcc.h>
+#include <libopencm3/stm32/gpio.h>
+#include <libopencm3/stm32/usart.h>
+#include <libopencm3/stm32/crypto.h>
+
+static void clock_setup(void)
+{
+	/* Enable GPIOD clock for LED & USARTs. */
+	rcc_peripheral_enable_clock(&RCC_AHB1ENR, RCC_AHB1ENR_IOPDEN);
+	rcc_peripheral_enable_clock(&RCC_AHB1ENR, RCC_AHB1ENR_IOPAEN);
+
+	/* Enable clocks for USART2. */
+	rcc_peripheral_enable_clock(&RCC_APB1ENR, RCC_APB1ENR_USART2EN);
+	
+	/* Enable clocks for CRYP. */
+	rcc_peripheral_enable_clock(&RCC_AHB2ENR, RCC_AHB2ENR_CRYPEN);
+}
+
+static void usart_setup(void)
+{
+	/* Setup USART2 parameters. */
+	usart_set_baudrate(USART2, 38400);
+	usart_set_databits(USART2, 8);
+	usart_set_stopbits(USART2, USART_STOPBITS_1);
+	usart_set_mode(USART2, USART_MODE_TX);
+	usart_set_parity(USART2, USART_PARITY_NONE);
+	usart_set_flow_control(USART2, USART_FLOWCONTROL_NONE);
+
+	/* Finally enable the USART. */
+	usart_enable(USART2);
+}
+
+static void gpio_setup(void)
+{
+	/* Setup GPIO pin GPIO12 on GPIO port D for LED. */
+	gpio_mode_setup(GPIOD, GPIO_MODE_OUTPUT, GPIO_PUPD_NONE, GPIO12);
+
+	/* Setup GPIO pins for USART2 transmit. */
+	gpio_mode_setup(GPIOA, GPIO_MODE_AF, GPIO_PUPD_NONE, GPIO2);
+
+	/* Setup USART2 TX pin as alternate function. */
+	gpio_set_af(GPIOA, GPIO_AF7, GPIO2);
+}
+
+static uint64_t key[4] = {0x11223344,0x44556677,0x77889900, 0x99005522};
+static uint64_t iv[4] = {0x01020304,0x02030405,0x09080706, 0x55245711};
+
+static uint8_t plaintext[8] = { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
+static uint8_t ciphertext[8] = { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
+static uint8_t plaintext2[8] = { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00}; 
+
+int main(void)
+{
+	int i;
+	int iserr = 1;
+
+	clock_setup();
+	gpio_setup();
+	usart_setup();
+
+	/* Blink the LED (PD12) on the board with every transmitted byte. */
+	while (1) {
+		gpio_toggle(GPIOD, GPIO12);	/* LED on/off */
+		
+		/* encode the plaintext message into ciphertext */
+
+		crypto_set_key(CRYPTO_KEY_128BIT,key);
+		crypto_set_iv(iv); /* only in CBC or CTR mode */
+		crypto_set_datatype(CRYPTO_DATA_32BIT);
+		crypto_set_algorithm(ENCRYPT_DES_ECB);
+
+		crypto_start();
+		crypto_process_block((uint32_t*)plaintext,
+				     (uint32_t*)ciphertext,
+				      8 / sizeof(uint32_t));
+		crypto_stop();
+
+		/* decode the previously encoded message
+		   from ciphertext to plaintext2 */
+
+		crypto_set_key(CRYPTO_KEY_128BIT,key);
+		crypto_set_iv(iv); /* only in CBC or CTR mode */
+		crypto_set_datatype(CRYPTO_DATA_32BIT);
+		crypto_set_algorithm(DECRYPT_DES_ECB);
+
+		crypto_start();
+		crypto_process_block((uint32_t*)ciphertext,
+				     (uint32_t*)plaintext2,
+				      8 / sizeof(uint32_t));
+		crypto_stop();	
+
+		/* compare the two plaintexts if they are same */
+		iserr = 0;
+		for (i=0; i<8; i++)
+		{
+			if (plaintext[i] != plaintext2[i])
+				iserr = true;
+		}
+
+		if (iserr)
+			gpio_toggle(GPIOD,GPIO12); /* something went wrong. */
+	}
+
+	return 0;
+}