github.com/mattn/go@v0.0.0-20171011075504-07f7db3ea99f/src/crypto/elliptic/p224_test.go (about)

     1  // Copyright 2012 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package elliptic
     6  
     7  import (
     8  	"math/big"
     9  	"testing"
    10  )
    11  
    12  var toFromBigTests = []string{
    13  	"0",
    14  	"1",
    15  	"23",
    16  	"b70e0cb46bb4bf7f321390b94a03c1d356c01122343280d6105c1d21",
    17  	"706a46d476dcb76798e6046d89474788d164c18032d268fd10704fa6",
    18  }
    19  
    20  func p224AlternativeToBig(in *p224FieldElement) *big.Int {
    21  	ret := new(big.Int)
    22  	tmp := new(big.Int)
    23  
    24  	for i := uint(0); i < 8; i++ {
    25  		tmp.SetInt64(int64(in[i]))
    26  		tmp.Lsh(tmp, 28*i)
    27  		ret.Add(ret, tmp)
    28  	}
    29  	ret.Mod(ret, p224.P)
    30  	return ret
    31  }
    32  
    33  func TestToFromBig(t *testing.T) {
    34  	for i, test := range toFromBigTests {
    35  		n, _ := new(big.Int).SetString(test, 16)
    36  		var x p224FieldElement
    37  		p224FromBig(&x, n)
    38  		m := p224ToBig(&x)
    39  		if n.Cmp(m) != 0 {
    40  			t.Errorf("#%d: %x != %x", i, n, m)
    41  		}
    42  		q := p224AlternativeToBig(&x)
    43  		if n.Cmp(q) != 0 {
    44  			t.Errorf("#%d: %x != %x (alternative)", i, n, m)
    45  		}
    46  	}
    47  }