Contents

#include "ruby.h"
#include "yubikey.h"

/*
 * call-seq:
 *   decrypt(state, key) -> plaintext
 *
 * Decrypt 16 bytes of binary AES ciphertext to binary plaintext with the Yubico implementation of AES-128 ECB
 * 
 * [+state+] 16 bytes of binary ciphertext
 * [+key+] 16-byte binary key
 *
 */
static VALUE
aes_decrypt(VALUE self, VALUE state, VALUE key) {
  char* state_ptr = StringValuePtr(state);
  char* key_ptr = StringValuePtr(key);
  
  if (RSTRING(state)->len != YUBIKEY_BLOCK_SIZE || RSTRING(key)->len != YUBIKEY_KEY_SIZE)
    rb_raise(rb_eArgError, "key and state must be 16 bytes");
  
  yubikey_aes_decrypt((uint8_t*)state_ptr, (uint8_t*)key_ptr);
  
  return rb_str_new(state_ptr, YUBIKEY_BLOCK_SIZE);
}

/*
 * call-seq:
 *   valid?(token)
 *
 * Check the CRC of a decrypted Yubikey OTP
 *
 * [+token+] 16-byte binary token
 */
static VALUE
crc_check(VALUE self, VALUE token) {
  char* token_ptr = StringValuePtr(token);
  
  if (RSTRING(token)->len != YUBIKEY_BLOCK_SIZE)
    rb_raise(rb_eArgError, "token must be 16 bytes");
  
  return yubikey_crc_ok_p((uint8_t*)token_ptr) ? Qtrue : Qfalse;
}

void
Init_yubikey_ext() {
  VALUE rb_mYubikey = rb_define_module("Yubikey");
  VALUE rb_mYubikeyAES = rb_define_module_under(rb_mYubikey, "AES");
  VALUE rb_mYubikeyCRC = rb_define_module_under(rb_mYubikey, "CRC");

  rb_define_module_function(rb_mYubikeyAES, "decrypt", aes_decrypt, 2);
  rb_define_module_function(rb_mYubikeyCRC, "valid?", crc_check, 1);
}

Version data entries

6 entries across 6 versions & 2 rubygems

Version	Path
titanous-yubikey-1.0.2	ext/yubikey_ext/yubikey_ext.c
titanous-yubikey-1.1.0	ext/yubikey_ext/yubikey_ext.c
titanous-yubikey-1.1.1	ext/yubikey_ext/yubikey_ext.c
yubikey-1.0.2	ext/yubikey_ext/yubikey_ext.c
yubikey-1.1.0	ext/yubikey_ext/yubikey_ext.c
yubikey-1.1.1	ext/yubikey_ext/yubikey_ext.c