add circuitpython code

1 files changed, 35 insertions, 0 deletions

diff --git a/circuitpython/lib/crypto-algorithms/sha256.h b/circuitpython/lib/crypto-algorithms/sha256.h
new file mode 100644
index 0000000..9c19472
--- /dev/null
+++ b/circuitpython/lib/crypto-algorithms/sha256.h
@@ -0,0 +1,35 @@
+/*********************************************************************
+* Source:     https://github.com/B-Con/crypto-algorithms
+* Filename:   sha256.h
+* Author:     Brad Conte (brad AT bradconte.com)
+* Copyright:  This code is released into the public domain.
+* 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>
+
+/****************************** MACROS ******************************/
+#define SHA256_BLOCK_SIZE 32            // SHA256 outputs a 32 byte digest
+
+/**************************** DATA TYPES ****************************/
+typedef unsigned char BYTE;             // 8-bit byte
+typedef unsigned int  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];
+} CRYAL_SHA256_CTX;
+
+/*********************** FUNCTION DECLARATIONS **********************/
+void sha256_init(CRYAL_SHA256_CTX *ctx);
+void sha256_update(CRYAL_SHA256_CTX *ctx, const BYTE data[], size_t len);
+void sha256_final(CRYAL_SHA256_CTX *ctx, BYTE hash[]);
+
+#endif   // SHA256_H