// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package hmac

import (
	"bytes"
	"crypto/md5"
	"crypto/sha1"
	"crypto/sha256"
	"crypto/sha512"
	"fmt"
	"hash"
	"testing"
)

type hmacTest struct {
	hash      func() hash.Hash
	key       []byte
	in        []byte
	out       string
	size      int
	blocksize int
}

var hmacTests = []hmacTest{
	// Tests from US FIPS 198
	// https://csrc.nist.gov/publications/fips/fips198/fips-198a.pdf
	{
		sha1.New,
		[]byte{
			0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
			0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
			0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
			0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
			0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
			0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
			0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
			0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
		},
		[]byte("Sample #1"),
		"4f4ca3d5d68ba7cc0a1208c9c61e9c5da0403c0a",
		sha1.Size,
		sha1.BlockSize,
	},
	{
		sha1.New,
		[]byte{
			0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
			0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
			0x40, 0x41, 0x42, 0x43,
		},
		[]byte("Sample #2"),
		"0922d3405faa3d194f82a45830737d5cc6c75d24",
		sha1.Size,
		sha1.BlockSize,
	},
	{
		sha1.New,
		[]byte{
			0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,
			0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f,
			0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,
			0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f,
			0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77,
			0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f,
			0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
			0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,
			0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97,
			0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f,
			0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,
			0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf,
			0xb0, 0xb1, 0xb2, 0xb3,
		},
		[]byte("Sample #3"),
		"bcf41eab8bb2d802f3d05caf7cb092ecf8d1a3aa",
		sha1.Size,
		sha1.BlockSize,
	},

	// Test from Plan 9.
	{
		md5.New,
		[]byte("Jefe"),
		[]byte("what do ya want for nothing?"),
		"750c783e6ab0b503eaa86e310a5db738",
		md5.Size,
		md5.BlockSize,
	},

	// Tests from RFC 4231
	{
		sha256.New,
		[]byte{
			0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b,
			0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b,
			0x0b, 0x0b, 0x0b, 0x0b,
		},
		[]byte("Hi There"),
		"b0344c61d8db38535ca8afceaf0bf12b881dc200c9833da726e9376c2e32cff7",
		sha256.Size,
		sha256.BlockSize,
	},
	{
		sha256.New,
		[]byte("Jefe"),
		[]byte("what do ya want for nothing?"),
		"5bdcc146bf60754e6a042426089575c75a003f089d2739839dec58b964ec3843",
		sha256.Size,
		sha256.BlockSize,
	},
	{
		sha256.New,
		[]byte{
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa,
		},
		[]byte{
			0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd,
			0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd,
			0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd,
			0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd,
			0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd,
			0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd,
			0xdd, 0xdd,
		},
		"773ea91e36800e46854db8ebd09181a72959098b3ef8c122d9635514ced565fe",
		sha256.Size,
		sha256.BlockSize,
	},
	{
		sha256.New,
		[]byte{
			0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08,
			0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10,
			0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18,
			0x19,
		},
		[]byte{
			0xcd, 0xcd, 0xcd, 0xcd, 0xcd, 0xcd, 0xcd, 0xcd,
			0xcd, 0xcd, 0xcd, 0xcd, 0xcd, 0xcd, 0xcd, 0xcd,
			0xcd, 0xcd, 0xcd, 0xcd, 0xcd, 0xcd, 0xcd, 0xcd,
			0xcd, 0xcd, 0xcd, 0xcd, 0xcd, 0xcd, 0xcd, 0xcd,
			0xcd, 0xcd, 0xcd, 0xcd, 0xcd, 0xcd, 0xcd, 0xcd,
			0xcd, 0xcd, 0xcd, 0xcd, 0xcd, 0xcd, 0xcd, 0xcd,
			0xcd, 0xcd,
		},
		"82558a389a443c0ea4cc819899f2083a85f0faa3e578f8077a2e3ff46729665b",
		sha256.Size,
		sha256.BlockSize,
	},
	{
		sha256.New,
		[]byte{
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa,
		},
		[]byte("Test Using Larger Than Block-Size Key - Hash Key First"),
		"60e431591ee0b67f0d8a26aacbf5b77f8e0bc6213728c5140546040f0ee37f54",
		sha256.Size,
		sha256.BlockSize,
	},
	{
		sha256.New,
		[]byte{
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa,
		},
		[]byte("This is a test using a larger than block-size key " +
			"and a larger than block-size data. The key needs to " +
			"be hashed before being used by the HMAC algorithm."),
		"9b09ffa71b942fcb27635fbcd5b0e944bfdc63644f0713938a7f51535c3a35e2",
		sha256.Size,
		sha256.BlockSize,
	},

	// Tests from https://csrc.nist.gov/groups/ST/toolkit/examples.html
	// (truncated tag tests are left out)
	{
		sha1.New,
		[]byte{
			0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
			0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
			0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
			0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
			0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
			0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
			0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
			0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
		},
		[]byte("Sample message for keylen=blocklen"),
		"5fd596ee78d5553c8ff4e72d266dfd192366da29",
		sha1.Size,
		sha1.BlockSize,
	},
	{
		sha1.New,
		[]byte{
			0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
			0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
			0x10, 0x11, 0x12, 0x13,
		},
		[]byte("Sample message for keylen<blocklen"),
		"4c99ff0cb1b31bd33f8431dbaf4d17fcd356a807",
		sha1.Size,
		sha1.BlockSize,
	},
	{
		sha1.New,
		[]byte{
			0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
			0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
			0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
			0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
			0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
			0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
			0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
			0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
			0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
			0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
			0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,
			0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f,
			0x60, 0x61, 0x62, 0x63,
		},
		[]byte("Sample message for keylen=blocklen"),
		"2d51b2f7750e410584662e38f133435f4c4fd42a",
		sha1.Size,
		sha1.BlockSize,
	},
	{
		sha256.New224,
		[]byte{
			0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
			0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
			0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
			0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
			0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
			0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
			0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
			0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
		},
		[]byte("Sample message for keylen=blocklen"),
		"c7405e3ae058e8cd30b08b4140248581ed174cb34e1224bcc1efc81b",
		sha256.Size224,
		sha256.BlockSize,
	},
	{
		sha256.New224,
		[]byte{
			0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
			0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
			0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
			0x18, 0x19, 0x1a, 0x1b,
		},
		[]byte("Sample message for keylen<blocklen"),
		"e3d249a8cfb67ef8b7a169e9a0a599714a2cecba65999a51beb8fbbe",
		sha256.Size224,
		sha256.BlockSize,
	},
	{
		sha256.New224,
		[]byte{
			0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
			0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
			0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
			0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
			0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
			0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
			0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
			0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
			0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
			0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
			0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,
			0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f,
			0x60, 0x61, 0x62, 0x63,
		},
		[]byte("Sample message for keylen=blocklen"),
		"91c52509e5af8531601ae6230099d90bef88aaefb961f4080abc014d",
		sha256.Size224,
		sha256.BlockSize,
	},
	{
		sha256.New,
		[]byte{
			0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
			0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
			0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
			0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
			0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
			0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
			0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
			0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
		},
		[]byte("Sample message for keylen=blocklen"),
		"8bb9a1db9806f20df7f77b82138c7914d174d59e13dc4d0169c9057b133e1d62",
		sha256.Size,
		sha256.BlockSize,
	},
	{
		sha256.New,
		[]byte{
			0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
			0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
			0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
			0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
		},
		[]byte("Sample message for keylen<blocklen"),
		"a28cf43130ee696a98f14a37678b56bcfcbdd9e5cf69717fecf5480f0ebdf790",
		sha256.Size,
		sha256.BlockSize,
	},
	{
		sha256.New,
		[]byte{
			0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
			0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
			0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
			0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
			0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
			0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
			0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
			0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
			0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
			0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
			0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,
			0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f,
			0x60, 0x61, 0x62, 0x63,
		},
		[]byte("Sample message for keylen=blocklen"),
		"bdccb6c72ddeadb500ae768386cb38cc41c63dbb0878ddb9c7a38a431b78378d",
		sha256.Size,
		sha256.BlockSize,
	},
	{
		sha512.New384,
		[]byte{
			0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
			0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
			0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
			0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
			0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
			0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
			0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
			0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
			0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
			0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
			0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,
			0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f,
			0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,
			0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f,
			0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77,
			0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f,
		},
		[]byte("Sample message for keylen=blocklen"),
		"63c5daa5e651847ca897c95814ab830bededc7d25e83eef9195cd45857a37f448947858f5af50cc2b1b730ddf29671a9",
		sha512.Size384,
		sha512.BlockSize,
	},
	{
		sha512.New384,
		[]byte{
			0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
			0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
			0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
			0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
			0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
			0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
		},
		[]byte("Sample message for keylen<blocklen"),
		"6eb242bdbb582ca17bebfa481b1e23211464d2b7f8c20b9ff2201637b93646af5ae9ac316e98db45d9cae773675eeed0",
		sha512.Size384,
		sha512.BlockSize,
	},
	{
		sha512.New384,
		[]byte{
			0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
			0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
			0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
			0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
			0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
			0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
			0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
			0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
			0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
			0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
			0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,
			0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f,
			0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,
			0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f,
			0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77,
			0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f,
			0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
			0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,
			0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97,
			0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f,
			0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,
			0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf,
			0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7,
			0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf,
			0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7,
		},
		[]byte("Sample message for keylen=blocklen"),
		"5b664436df69b0ca22551231a3f0a3d5b4f97991713cfa84bff4d0792eff96c27dccbbb6f79b65d548b40e8564cef594",
		sha512.Size384,
		sha512.BlockSize,
	},
	{
		sha512.New,
		[]byte{
			0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
			0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
			0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
			0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
			0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
			0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
			0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
			0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
			0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
			0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
			0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,
			0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f,
			0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,
			0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f,
			0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77,
			0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f,
		},
		[]byte("Sample message for keylen=blocklen"),
		"fc25e240658ca785b7a811a8d3f7b4ca" +
			"48cfa26a8a366bf2cd1f836b05fcb024bd36853081811d6c" +
			"ea4216ebad79da1cfcb95ea4586b8a0ce356596a55fb1347",
		sha512.Size,
		sha512.BlockSize,
	},
	{
		sha512.New,
		[]byte{
			0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
			0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
			0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
			0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
			0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
			0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
			0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
			0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
		},
		[]byte("Sample message for keylen<blocklen"),
		"fd44c18bda0bb0a6ce0e82b031bf2818" +
			"f6539bd56ec00bdc10a8a2d730b3634de2545d639b0f2cf7" +
			"10d0692c72a1896f1f211c2b922d1a96c392e07e7ea9fedc",
		sha512.Size,
		sha512.BlockSize,
	},
	{
		sha512.New,
		[]byte{
			0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
			0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
			0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
			0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
			0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
			0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
			0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
			0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
			0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
			0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
			0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,
			0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f,
			0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,
			0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f,
			0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77,
			0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f,
			0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
			0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,
			0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97,
			0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f,
			0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,
			0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf,
			0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7,
			0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf,
			0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7,
		},
		[]byte("Sample message for keylen=blocklen"),
		"d93ec8d2de1ad2a9957cb9b83f14e76a" +
			"d6b5e0cce285079a127d3b14bccb7aa7286d4ac0d4ce6421" +
			"5f2bc9e6870b33d97438be4aaa20cda5c5a912b48b8e27f3",
		sha512.Size,
		sha512.BlockSize,
	},
	// HMAC without key is dumb but should probably not fail.
	{
		sha1.New,
		[]byte{},
		[]byte("message"),
		"d5d1ed05121417247616cfc8378f360a39da7cfa",
		sha1.Size,
		sha1.BlockSize,
	},
	{
		sha256.New,
		[]byte{},
		[]byte("message"),
		"eb08c1f56d5ddee07f7bdf80468083da06b64cf4fac64fe3a90883df5feacae4",
		sha256.Size,
		sha256.BlockSize,
	},
	{
		sha512.New,
		[]byte{},
		[]byte("message"),
		"08fce52f6395d59c2a3fb8abb281d74ad6f112b9a9c787bcea290d94dadbc82b2ca3e5e12bf2277c7fedbb0154d5493e41bb7459f63c8e39554ea3651b812492",
		sha512.Size,
		sha512.BlockSize,
	},
}

func TestHMAC(t *testing.T) {
	for i, tt := range hmacTests {
		h := New(tt.hash, tt.key)
		if s := h.Size(); s != tt.size {
			t.Errorf("Size: got %v, want %v", s, tt.size)
		}
		if b := h.BlockSize(); b != tt.blocksize {
			t.Errorf("BlockSize: got %v, want %v", b, tt.blocksize)
		}
		for j := 0; j < 2; j++ {
			n, err := h.Write(tt.in)
			if n != len(tt.in) || err != nil {
				t.Errorf("test %d.%d: Write(%d) = %d, %v", i, j, len(tt.in), n, err)
				continue
			}

			// Repetitive Sum() calls should return the same value
			for k := 0; k < 2; k++ {
				sum := fmt.Sprintf("%x", h.Sum(nil))
				if sum != tt.out {
					t.Errorf("test %d.%d.%d: have %s want %s\n", i, j, k, sum, tt.out)
				}
			}

			// Second iteration: make sure reset works.
			h.Reset()
		}
	}
}

func TestEqual(t *testing.T) {
	a := []byte("test")
	b := []byte("test1")
	c := []byte("test2")

	if !Equal(b, b) {
		t.Error("Equal failed with equal arguments")
	}
	if Equal(a, b) {
		t.Error("Equal accepted a prefix of the second argument")
	}
	if Equal(b, a) {
		t.Error("Equal accepted a prefix of the first argument")
	}
	if Equal(b, c) {
		t.Error("Equal accepted unequal slices")
	}
}

func TestWriteAfterSum(t *testing.T) {
	h := New(sha1.New, nil)
	h.Write([]byte("hello"))
	sumHello := h.Sum(nil)

	h = New(sha1.New, nil)
	h.Write([]byte("hello world"))
	sumHelloWorld := h.Sum(nil)

	// Test that Sum has no effect on future Sum or Write operations.
	// This is a bit unusual as far as usage, but it's allowed
	// by the definition of Go hash.Hash, and some clients expect it to work.
	h = New(sha1.New, nil)
	h.Write([]byte("hello"))
	if sum := h.Sum(nil); !bytes.Equal(sum, sumHello) {
		t.Fatalf("1st Sum after hello = %x, want %x", sum, sumHello)
	}
	if sum := h.Sum(nil); !bytes.Equal(sum, sumHello) {
		t.Fatalf("2nd Sum after hello = %x, want %x", sum, sumHello)
	}

	h.Write([]byte(" world"))
	if sum := h.Sum(nil); !bytes.Equal(sum, sumHelloWorld) {
		t.Fatalf("1st Sum after hello world = %x, want %x", sum, sumHelloWorld)
	}
	if sum := h.Sum(nil); !bytes.Equal(sum, sumHelloWorld) {
		t.Fatalf("2nd Sum after hello world = %x, want %x", sum, sumHelloWorld)
	}

	h.Reset()
	h.Write([]byte("hello"))
	if sum := h.Sum(nil); !bytes.Equal(sum, sumHello) {
		t.Fatalf("Sum after Reset + hello = %x, want %x", sum, sumHello)
	}
}

func BenchmarkHMACSHA256_1K(b *testing.B) {
	key := make([]byte, 32)
	buf := make([]byte, 1024)
	h := New(sha256.New, key)
	b.SetBytes(int64(len(buf)))
	for i := 0; i < b.N; i++ {
		h.Write(buf)
		h.Reset()
		mac := h.Sum(nil)
		buf[0] = mac[0]
	}
}

func BenchmarkHMACSHA256_32(b *testing.B) {
	key := make([]byte, 32)
	buf := make([]byte, 32)
	h := New(sha256.New, key)
	b.SetBytes(int64(len(buf)))
	for i := 0; i < b.N; i++ {
		h.Write(buf)
		h.Reset()
		mac := h.Sum(nil)
		buf[0] = mac[0]
	}
}