The old repo for this was abandoned and no longer works with the Arduino IDE v1.6+

I have implemented a few changes so it now compiles. Below is the original readme (with a bit of formatting).

###Description

Cryptosuite is a cryptographic library for Arduino (including SHA and HMAC-SHA).

It currently supports secure hashing and hashed message authentication using SHA-1, SHA-256, HMAC-SHA-1 and HMAC-SHA-256.

Installation:

• Make a 'libraries' directory with your Arduino sketches folder if you do not already have one.
• Copy the 'Sha' directory of this project into that directory.
• Restart the Arduino IDE to rescan for new libraries.

###Using SHA-1:

  #include "sha1.h"
  ...
  uint8_t *hash;
  Sha1.init();
  Sha1.print("This is a message to hash");
  hash = Sha1.result();

The hash result is then stored in hash[0], hash[1] .. hash[19].

###Using HMAC-SHA-1:

  #include "sha1.h"
  ...
  uint8_t *hash;
  Sha1.initHmac("hash key",8); // key, and length of key in bytes
  Sha1.print("This is a message to hash");
  hash = Sha1.resultHmac();

The hash result is then stored in hash[0], hash[1] .. hash[19].

###Using SHA-256:

  #include "sha256.h"
  ...
  uint8_t *hash;
  Sha256.init();
  Sha256.print("This is a message to hash");
  hash = Sha256.result();

The hash result is then stored in hash[0], hash[1] .. hash[31].

Using HMAC-SHA-256:

  #include "sha256.h"
  ...
  uint8_t *hash;
  Sha256.initHmac("hash key",8); // key, and length of key in bytes
  Sha256.print("This is a message to hash");
  hash = Sha256.resultHmac();

The hash result is then stored in hash[0], hash[1] .. hash[31].

###Verification:

The provided example code tests against published test vectors.

• SHA-1: FIPS 180-2, RFC3174 compliant
• HMAC-SHA-1: FIPS 198a compliant
• SHA-256: FIPS 180-2, RFC4231 compliant
• HMAC-SHA-256: RFC4231 compliant