libskarnet
skalibs
Software
skarnet.org

The stdcrypto library interface

stdcrypto is a small collection of standard, public-domain cryptographic primitives. Currently, the following operations are provided:

• rc4
• md5
• sha1
• sha256
• sha512

Please bear in mind that rc4 and md5 are broken, and that sha1 is about to be. Do not use them in security-critical applications.

Compiling

• Use #include <skalibs/stdcrypto.h>

Programming

You should refer to the skalibs/stdcrypto.h header and included headers for the exact function prototypes.

RC4

  RC4Schedule ctx ;
  unsigned char const *key ;
  size_t keylen ;
  unsigned char const *in ;
  unsigned char *out ;
  size_t len ;

  rc4_init(&ctx, key, keylen) ;
  rc4(&ctx, in, out, len) ;

MD5

  MD5Schedule ctx ;
  char const *message ;
  size_t messagelen ;
  char digest[16] ;

  md5_init(&ctx) ;
  md5_update(&ctx, message, messagelen) ;
  md5_final(&ctx, digest) ;

SHA1

  SHA1Schedule ctx ;
  char const *message ;
  size_t messagelen ;
  unsigned char digest[20] ;

  sha1_init(&ctx) ;
  sha1_update(&ctx, message, messagelen) ;
  sha1_final(&ctx, digest) ;

• sha1_init() prepares a SHA1Schedule structure for computation
• sha1_update() adds message to the message to be digested
• sha1_final() computes the digest

SHA256

  SHA256Schedule ctx ;
  char const *message ;
  size_t messagelen ;
  char digest[32] ;

  sha256_init(&ctx) ;
  sha256_update(&ctx, message, messagelen) ;
  sha256_final(&ctx, digest) ;

• sha256_init() prepares a SHA256Schedule structure for computation
• sha256_update() adds message to the message to be digested
• sha256_final() computes the digest

SHA512

  SHA512Schedule ctx ;
  char const *message ;
  size_t messagelen ;
  char digest[64] ;

  sha512_init(&ctx) ;
  sha512_update(&ctx, message, messagelen) ;
  sha512_final(&ctx, digest) ;

• sha512_init() prepares a SHA512Schedule structure for computation
• sha512_update() adds message to the message to be digested
• sha512_final() computes the digest