Ruby » Ruby trunk

 *  call-seq:

 *     hmac.verify(bytes) -> aBoolean

 *

 * Compares the receiver's digest to another digest in a timing-safe way.

 * +bytes+ must be a binary string containing a digest, for example by calling +#digest+ on another

 * instance of +OpenSSL::Digest+.

 */

VALUE

ossl_hmac_verify(VALUE self, VALUE other)

{

  HMAC_CTX *ctx;

  unsigned char *buf;

  unsigned int buf_len;

  unsigned char result;

  unsigned int cur_idx;

  unsigned char *other_buf;

  if (!RB_TYPE_P(other, T_STRING))

    rb_raise(rb_eArgError, "digest value must be a string");

  GetHMAC(self, ctx);

  hmac_final(ctx, &buf, &buf_len);

  if (!buf_len || buf_len != RSTRING_LEN(other))

    return Qfalse;

  other_buf = (unsigned char *)RSTRING_PTR(other);

  result = 0;

  for (cur_idx = 0; cur_idx < buf_len; cur_idx++) {

    result |= buf[cur_idx] ^ other_buf[cur_idx];

  }

  if (result == 0)

    return Qtrue;

  return Qfalse;

}

/*

    rb_define_method(cHMAC, "verify", ossl_hmac_verify, 1);

    assert_same(false, @h1.verify("\x9EPYl\x0F\xA1\x19\x7F\x85\x87D:\x94-\x8A\xFD"))

    assert_same(true, @h1.verify("\x9EPYl\x0F\xA1\x19\x7F\x85\x87D:\x94-\x8A\xFC"))

  end

  def test_hmac_verify