sha

cube/User/Inc/config.h

@@ -5,6 +5,8 @@
 #include <spi.h>
 #include <assert.h>
 
+#include <sha256.h>
+
 #define CONFIG_MAGIC 0xdead0006
 
 typedef struct __attribute__((__packed__)) s_configBlock {
@@ -13,7 +15,7 @@ typedef struct __attribute__((__packed__)) s_configBlock {
     uint8_t macAddress[6];
     char ntpServer[48];
     char deviceId[16];
-    char sharedSecret[32];
+    char sharedSecret[SHA256_BLOCK_SIZE];
     char location[48];
     char sinkServer[48];
     uint8_t filler[6];

cube/User/Inc/sha256.h

@@ -0,0 +1,35 @@
+/*********************************************************************
+* Filename:   sha256.h
+* Author:     Brad Conte (brad AT bradconte.com)
+* Copyright:
+* Disclaimer: This code is presented "as is" without any guarantees.
+* Details:    Defines the API for the corresponding SHA1 implementation.
+*********************************************************************/
+
+#ifndef SHA256_H
+#define SHA256_H
+
+/*************************** HEADER FILES ***************************/
+#include <stddef.h>
+#include <stdint.h>
+
+/****************************** MACROS ******************************/
+#define SHA256_BLOCK_SIZE 32            // SHA256 outputs a 32 byte digest
+
+/**************************** DATA TYPES ****************************/
+typedef uint8_t BYTE;             // 8-bit byte
+typedef uint32_t  WORD;             // 32-bit word, change to "long" for 16-bit machines
+
+typedef struct {
+	BYTE data[64];
+	WORD datalen;
+	unsigned long long bitlen;
+	WORD state[8];
+} SHA256_CTX;
+
+/*********************** FUNCTION DECLARATIONS **********************/
+void sha256_init(SHA256_CTX *ctx);
+void sha256_update(SHA256_CTX *ctx, const BYTE data[], size_t len);
+void sha256_final(SHA256_CTX *ctx, BYTE hash[]);
+
+#endif   // SHA256_H