Public AES block interface.

The higher-level stream modes will be in crypto/block.

R=r
DELTA=205  (136 added, 7 deleted, 62 changed)
OCL=29002
CL=29006

diff --git a/src/lib/crypto/aes/Makefile b/src/lib/crypto/aes/Makefile
index 309416324050b93f151a8b43c6de12ebdab57cef..f301d0cefb1dc21f11d752565fda38d5f178153d 100644 (file)
--- a/src/lib/crypto/aes/Makefile
+++ b/src/lib/crypto/aes/Makefile
@@ -41,23 +41,29 @@ coverage: packages
 
 O1=\
        const.$O\
-       modes.$O\
 
 O2=\
        block.$O\
 
+O3=\
+       cipher.$O\
 
-phases: a1 a2
+
+phases: a1 a2 a3
 _obj$D/aes.a: phases
 
 a1: $(O1)
-       $(AR) grc _obj$D/aes.a const.$O modes.$O
+       $(AR) grc _obj$D/aes.a const.$O
        rm -f $(O1)
 
 a2: $(O2)
        $(AR) grc _obj$D/aes.a block.$O
        rm -f $(O2)
 
+a3: $(O3)
+       $(AR) grc _obj$D/aes.a cipher.$O
+       rm -f $(O3)
+
 
 newpkg: clean
        mkdir -p _obj$D
@@ -66,6 +72,7 @@ newpkg: clean
 $(O1): newpkg
 $(O2): a1
 $(O3): a2
+$(O4): a3
 
 nuke: clean
        rm -f $(GOROOT)/pkg$D/aes.a

diff --git a/src/lib/crypto/aes/aes_test.go b/src/lib/crypto/aes/aes_test.go
index f16cf4b2da21427cf622ab96e1fcb8a28f55692c..2f6cb4a9230f4a4f9369e78a2fa4ee71647a6854 100644 (file)
--- a/src/lib/crypto/aes/aes_test.go
+++ b/src/lib/crypto/aes/aes_test.go
@@ -126,7 +126,7 @@ func TestTd(t *testing.T) {
 
 // Appendix A of FIPS 197: Key expansion examples
 type KeyTest struct {
-       key []uint32;
+       key []byte;
        enc []uint32;
        dec []uint32;   // decryption expansion; not in FIPS 197, computed from C implementation.
 }
@@ -134,8 +134,8 @@ type KeyTest struct {
 var keyTests = []KeyTest {
        KeyTest {
                // A.1.  Expansion of a 128-bit Cipher Key
-               []uint32 {
-                       0x2b7e1516, 0x28aed2a6, 0xabf71588, 0x09cf4f3c
+               []byte {
+                       0x2b, 0x7e, 0x15, 0x16, 0x28, 0xae, 0xd2, 0xa6, 0xab, 0xf7, 0x15, 0x88, 0x09, 0xcf, 0x4f, 0x3c
                },
                []uint32 {
                        0x2b7e1516, 0x28aed2a6, 0xabf71588, 0x09cf4f3c,
@@ -166,9 +166,9 @@ var keyTests = []KeyTest {
        },
        KeyTest {
                // A.2.  Expansion of a 192-bit Cipher Key
-               []uint32 {
-                       0x8e73b0f7, 0xda0e6452, 0xc810f32b, 0x809079e5,
-                       0x62f8ead2, 0x522c6b7b,
+               []byte {
+                       0x8e, 0x73, 0xb0, 0xf7, 0xda, 0x0e, 0x64, 0x52, 0xc8, 0x10, 0xf3, 0x2b, 0x80, 0x90, 0x79, 0xe5,
+                       0x62, 0xf8, 0xea, 0xd2, 0x52, 0x2c, 0x6b, 0x7b,
                },
                []uint32 {
                        0x8e73b0f7, 0xda0e6452, 0xc810f32b, 0x809079e5,
@@ -189,9 +189,9 @@ var keyTests = []KeyTest {
        },
        KeyTest {
                // A.3.  Expansion of a 256-bit Cipher Key
-               []uint32 {
-                       0x603deb10, 0x15ca71be, 0x2b73aef0, 0x857d7781,
-                       0x1f352c07, 0x3b6108d7, 0x2d9810a3, 0x0914dff4,
+               []byte {
+                       0x60, 0x3d, 0xeb, 0x10, 0x15, 0xca, 0x71, 0xbe, 0x2b, 0x73, 0xae, 0xf0, 0x85, 0x7d, 0x77, 0x81,
+                       0x1f, 0x35, 0x2c, 0x07, 0x3b, 0x61, 0x08, 0xd7, 0x2d, 0x98, 0x10, 0xa3, 0x09, 0x14, 0xdf, 0xf4,
                },
                []uint32 {
                        0x603deb10, 0x15ca71be, 0x2b73aef0, 0x857d7781,
@@ -243,70 +243,108 @@ L:
 
 // Appendix B, C of FIPS 197: Cipher examples, Example vectors.
 type CryptTest struct {
-       key []uint32;
-       in []uint32;
-       out []uint32;
+       key []byte;
+       in []byte;
+       out []byte;
 }
 
 var encryptTests = []CryptTest {
        CryptTest {
                // Appendix B.
-               []uint32 { 0x2b7e1516, 0x28aed2a6, 0xabf71588, 0x09cf4f3c, },
-               []uint32 { 0x3243f6a8, 0x885a308d, 0x313198a2, 0xe0370734, },
-               []uint32 { 0x3925841d, 0x02dc09fb, 0xdc118597, 0x196a0b32, },
+               []byte { 0x2b, 0x7e, 0x15, 0x16, 0x28, 0xae, 0xd2, 0xa6, 0xab, 0xf7, 0x15, 0x88, 0x09, 0xcf, 0x4f, 0x3c, },
+               []byte { 0x32, 0x43, 0xf6, 0xa8, 0x88, 0x5a, 0x30, 0x8d, 0x31, 0x31, 0x98, 0xa2, 0xe0, 0x37, 0x07, 0x34, },
+               []byte { 0x39, 0x25, 0x84, 0x1d, 0x02, 0xdc, 0x09, 0xfb, 0xdc, 0x11, 0x85, 0x97, 0x19, 0x6a, 0x0b, 0x32, },
        },
        CryptTest {
                // Appendix C.1.  AES-128
-               []uint32 { 0x00010203, 0x04050607, 0x08090a0b, 0x0c0d0e0f, },
-               []uint32 { 0x00112233, 0x44556677, 0x8899aabb, 0xccddeeff, },
-               []uint32 { 0x69c4e0d8, 0x6a7b0430, 0xd8cdb780, 0x70b4c55a, },
+               []byte { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, },
+               []byte { 0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88, 0x99, 0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff, },
+               []byte { 0x69, 0xc4, 0xe0, 0xd8, 0x6a, 0x7b, 0x04, 0x30, 0xd8, 0xcd, 0xb7, 0x80, 0x70, 0xb4, 0xc5, 0x5a, },
        },
        CryptTest {
                // Appendix C.2.  AES-192
-               []uint32 { 0x00010203, 0x04050607, 0x08090a0b, 0x0c0d0e0f,
-                       0x10111213, 0x14151617, },
-               []uint32 { 0x00112233, 0x44556677, 0x8899aabb, 0xccddeeff, },
-               []uint32 { 0xdda97ca4, 0x864cdfe0, 0x6eaf70a0, 0xec0d7191, },
+               []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, },
+               []byte { 0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88, 0x99, 0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff, },
+               []byte { 0xdd, 0xa9, 0x7c, 0xa4, 0x86, 0x4c, 0xdf, 0xe0, 0x6e, 0xaf, 0x70, 0xa0, 0xec, 0x0d, 0x71, 0x91, },
        },
        CryptTest {
                // Appendix C.3.  AES-256
-               []uint32 { 0x00010203, 0x04050607, 0x08090a0b, 0x0c0d0e0f,
-                       0x10111213, 0x14151617, 0x18191a1b, 0x1c1d1e1f, },
-               []uint32 { 0x00112233, 0x44556677, 0x8899aabb, 0xccddeeff, },
-               []uint32 { 0x8ea2b7ca, 0x516745bf, 0xeafc4990, 0x4b496089, },
+               []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 { 0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88, 0x99, 0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff, },
+               []byte { 0x8e, 0xa2, 0xb7, 0xca, 0x51, 0x67, 0x45, 0xbf, 0xea, 0xfc, 0x49, 0x90, 0x4b, 0x49, 0x60, 0x89, },
        },
 }
 
-// Test encryption against FIPS 197 examples.
-func TestEncrypt(t *testing.T) {
+// Test encryptBlock against FIPS 197 examples.
+func TestEncryptBlock(t *testing.T) {
        for i, tt := range encryptTests {
-               n := 4*(len(tt.key) + 7);
+               n := len(tt.key) + 28;
                enc := make([]uint32, n);
                dec := make([]uint32, n);
                expandKey(tt.key, enc, dec);
-               out := make([]uint32, len(tt.in));
+               out := make([]byte, len(tt.in));
                encryptBlock(enc, tt.in, out);
                for j, v := range out {
                        if v != tt.out[j] {
-                               t.Errorf("encrypt %d: out[%d] = %#x, want %#x", i, j, v, tt.out[j]);
+                               t.Errorf("encryptBlock %d: out[%d] = %#x, want %#x", i, j, v, tt.out[j]);
                                break;
                        }
                }
        }
 }
 
-// Test decryption against FIPS 197 examples.
-func TestDecrypt(t *testing.T) {
+// Test decryptBlock against FIPS 197 examples.
+func TestDecryptBlock(t *testing.T) {
        for i, tt := range encryptTests {
-               n := 4*(len(tt.key) + 7);
+               n := len(tt.key) + 28;
                enc := make([]uint32, n);
                dec := make([]uint32, n);
                expandKey(tt.key, enc, dec);
-               plain := make([]uint32, len(tt.in));
+               plain := make([]byte, len(tt.in));
                decryptBlock(dec, tt.out, plain);
                for j, v := range plain {
                        if v != tt.in[j] {
-                               t.Errorf("decrypt %d: plain[%d] = %#x, want %#x", i, j, v, tt.in[j]);
+                               t.Errorf("decryptBlock %d: plain[%d] = %#x, want %#x", i, j, v, tt.in[j]);
+                               break;
+                       }
+               }
+       }
+}
+
+// Test Cipher Encrypt method against FIPS 197 examples.
+func TestCipherEncrypt(t *testing.T) {
+       for i, tt := range encryptTests {
+               c, err := NewCipher(tt.key);
+               if err != nil {
+                       t.Errorf("NewCipher(%d bytes) = %s", len(tt.key), err);
+                       continue;
+               }
+               out := make([]byte, len(tt.in));
+               c.Encrypt(tt.in, out);
+               for j, v := range out {
+                       if v != tt.out[j] {
+                               t.Errorf("Cipher.Encrypt %d: out[%d] = %#x, want %#x", i, j, v, tt.out[j]);
+                               break;
+                       }
+               }
+       }
+}
+
+// Test Cipher Decrypt against FIPS 197 examples.
+func TestCipherDecrypt(t *testing.T) {
+       for i, tt := range encryptTests {
+               c, err := NewCipher(tt.key);
+               if err != nil {
+                       t.Errorf("NewCipher(%d bytes) = %s", len(tt.key), err);
+                       continue;
+               }
+               plain := make([]byte, len(tt.in));
+               c.Decrypt(tt.out, plain);
+               for j, v := range plain {
+                       if v != tt.in[j] {
+                               t.Errorf("decryptBlock %d: plain[%d] = %#x, want %#x", i, j, v, tt.in[j]);
                                break;
                        }
                }

diff --git a/src/lib/crypto/aes/block.go b/src/lib/crypto/aes/block.go
index 56c48fe34302a93f860119e8930833a6c4bee3ae..3c67d1c3c057681293962cf10301fb93cede7f0a 100644 (file)
--- a/src/lib/crypto/aes/block.go
+++ b/src/lib/crypto/aes/block.go
@@ -39,14 +39,19 @@ package aes
 import "crypto/aes"
 
 // Encrypt one block from src into dst, using the expanded key xk.
-func encryptBlock(xk, src, dst []uint32) {
+func encryptBlock(xk []uint32, src, dst []byte) {
        var s0, s1, s2, s3, t0, t1, t2, t3 uint32;
 
+       s0 = uint32(src[0])<<24 | uint32(src[1])<<16 | uint32(src[2])<<8 | uint32(src[3]);
+       s1 = uint32(src[4])<<24 | uint32(src[5])<<16 | uint32(src[6])<<8 | uint32(src[7]);
+       s2 = uint32(src[8])<<24 | uint32(src[9])<<16 | uint32(src[10])<<8 | uint32(src[11]);
+       s3 = uint32(src[12])<<24 | uint32(src[13])<<16 | uint32(src[14])<<8 | uint32(src[15]);
+
        // First round just XORs input with key.
-       s0 = src[0] ^ xk[0];
-       s1 = src[1] ^ xk[1];
-       s2 = src[2] ^ xk[2];
-       s3 = src[3] ^ xk[3];
+       s0 ^= xk[0];
+       s1 ^= xk[1];
+       s2 ^= xk[2];
+       s3 ^= xk[3];
 
        // Middle rounds shuffle using tables.
        // Number of rounds is set by length of expanded key.
@@ -67,21 +72,31 @@ func encryptBlock(xk, src, dst []uint32) {
        s2 = uint32(sbox0[t2>>24])<<24 | uint32(sbox0[t3>>16 & 0xff])<<16 | uint32(sbox0[t0>>8 & 0xff])<<8 | uint32(sbox0[t1 & 0xff]);
        s3 = uint32(sbox0[t3>>24])<<24 | uint32(sbox0[t0>>16 & 0xff])<<16 | uint32(sbox0[t1>>8 & 0xff])<<8 | uint32(sbox0[t2 & 0xff]);
 
-       dst[0] = s0 ^ xk[k+0];
-       dst[1] = s1 ^ xk[k+1];
-       dst[2] = s2 ^ xk[k+2];
-       dst[3] = s3 ^ xk[k+3];
+       s0 ^= xk[k+0];
+       s1 ^= xk[k+1];
+       s2 ^= xk[k+2];
+       s3 ^= xk[k+3];
+
+       dst[0], dst[1], dst[2], dst[3] = byte(s0>>24), byte(s0>>16), byte(s0>>8), byte(s0);
+       dst[4], dst[5], dst[6], dst[7] = byte(s1>>24), byte(s1>>16), byte(s1>>8), byte(s1);
+       dst[8], dst[9], dst[10], dst[11] = byte(s2>>24), byte(s2>>16), byte(s2>>8), byte(s2);
+       dst[12], dst[13], dst[14], dst[15] = byte(s3>>24), byte(s3>>16), byte(s3>>8), byte(s3);
 }
 
 // Decrypt one block from src into dst, using the expanded key xk.
-func decryptBlock(xk, src, dst []uint32) {
+func decryptBlock(xk []uint32, src, dst []byte) {
        var s0, s1, s2, s3, t0, t1, t2, t3 uint32;
 
+       s0 = uint32(src[0])<<24 | uint32(src[1])<<16 | uint32(src[2])<<8 | uint32(src[3]);
+       s1 = uint32(src[4])<<24 | uint32(src[5])<<16 | uint32(src[6])<<8 | uint32(src[7]);
+       s2 = uint32(src[8])<<24 | uint32(src[9])<<16 | uint32(src[10])<<8 | uint32(src[11]);
+       s3 = uint32(src[12])<<24 | uint32(src[13])<<16 | uint32(src[14])<<8 | uint32(src[15]);
+
        // First round just XORs input with key.
-       s0 = src[0] ^ xk[0];
-       s1 = src[1] ^ xk[1];
-       s2 = src[2] ^ xk[2];
-       s3 = src[3] ^ xk[3];
+       s0 ^= xk[0];
+       s1 ^= xk[1];
+       s2 ^= xk[2];
+       s3 ^= xk[3];
 
        // Middle rounds shuffle using tables.
        // Number of rounds is set by length of expanded key.
@@ -102,10 +117,15 @@ func decryptBlock(xk, src, dst []uint32) {
        s2 = uint32(sbox1[t2>>24])<<24 | uint32(sbox1[t1>>16 & 0xff])<<16 | uint32(sbox1[t0>>8 & 0xff])<<8 | uint32(sbox1[t3 & 0xff]);
        s3 = uint32(sbox1[t3>>24])<<24 | uint32(sbox1[t2>>16 & 0xff])<<16 | uint32(sbox1[t1>>8 & 0xff])<<8 | uint32(sbox1[t0 & 0xff]);
 
-       dst[0] = s0 ^ xk[k+0];
-       dst[1] = s1 ^ xk[k+1];
-       dst[2] = s2 ^ xk[k+2];
-       dst[3] = s3 ^ xk[k+3];
+       s0 ^= xk[k+0];
+       s1 ^= xk[k+1];
+       s2 ^= xk[k+2];
+       s3 ^= xk[k+3];
+
+       dst[0], dst[1], dst[2], dst[3] = byte(s0>>24), byte(s0>>16), byte(s0>>8), byte(s0);
+       dst[4], dst[5], dst[6], dst[7] = byte(s1>>24), byte(s1>>16), byte(s1>>8), byte(s1);
+       dst[8], dst[9], dst[10], dst[11] = byte(s2>>24), byte(s2>>16), byte(s2>>8), byte(s2);
+       dst[12], dst[13], dst[14], dst[15] = byte(s3>>24), byte(s3>>16), byte(s3>>8), byte(s3);
 }
 
 // Apply sbox0 to each byte in w.
@@ -124,12 +144,12 @@ func rotw(w uint32) uint32 {
 
 // Key expansion algorithm.  See FIPS-197, Figure 11.
 // Their rcon[i] is our powx[i-1] << 24.
-func expandKey(key, enc, dec []uint32) {
+func expandKey(key []byte, enc, dec []uint32) {
        // Encryption key setup.
        var i int;
-       nk := len(key);
+       nk := len(key) / 4;
        for i = 0; i < nk; i++ {
-               enc[i] = key[i];
+               enc[i] = uint32(key[4*i])<<24 | uint32(key[4*i+1])<<16 | uint32(key[4*i+2])<<8 | uint32(key[4*i+3]);
        }
        for ; i < len(enc); i++ {
                t := enc[i-1];

diff --git a/src/lib/crypto/aes/cipher.go b/src/lib/crypto/aes/cipher.go
new file mode 100644 (file)
index 0000000..fd8e43e
--- /dev/null
+++ b/src/lib/crypto/aes/cipher.go
@@ -0,0 +1,71 @@
+// 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 aes
+
+import (
+       "crypto/aes";
+       "os";
+)
+
+// The AES block size in bytes.
+const BlockSize = 16;
+
+// A Cipher is an instance of AES encryption using a particular key.
+type Cipher struct {
+       enc []uint32;
+       dec []uint32;
+}
+
+// NewCipher creates and returns a new Cipher.
+// The key argument should be the AES key,
+// either 16, 24, or 32 bytes to select
+// AES-128, AES-192, or AES-256.
+func NewCipher(key []byte) (*Cipher, os.Error) {
+       switch len(key) {
+       default:
+               return nil, os.ErrorString("crypto/aes: invalid key size");
+       case 16, 24, 32:
+               break;
+       }
+
+       n := len(key) + 28;
+       c := &Cipher{make([]uint32, n), make([]uint32, n)};
+       expandKey(key, c.enc, c.dec);
+       return c, nil;
+}
+
+// BlockSize returns the AES block size, 16 bytes.
+// It is necessary to satisfy the Key interface in the
+// package "crypto/modes".
+func (c *Cipher) BlockSize() int {
+       return BlockSize;
+}
+
+// Encrypt encrypts the 16-byte buffer src using the key k
+// and stores the result in dst.
+// Note that for amounts of data larger than a block,
+// it is not safe to just call Encrypt on successive blocks;
+// instead, use an encryption mode like AESCBC (see modes.go).
+func (c *Cipher) Encrypt(src, dst []byte) {
+       encryptBlock(c.enc, src, dst);
+}
+
+// Decrypt decrypts the 16-byte buffer src using the key k
+// and stores the result in dst.
+func (c *Cipher) Decrypt(src, dst []byte) {
+       decryptBlock(c.dec, src, dst);
+}
+
+// Reset zeros the key data, so that it will no longer
+// appear in the process's memory.
+func (c *Cipher) Reset() {
+       for i := 0; i < len(c.enc); i++ {
+               c.enc[i] = 0;
+       }
+       for i := 0; i < len(c.dec); i++ {
+               c.dec[i] = 0;
+       }
+}
+

diff --git a/src/lib/crypto/aes/modes.go b/src/lib/crypto/aes/modes.go
deleted file mode 100644 (file)
index 96d0154..0000000
--- a/src/lib/crypto/aes/modes.go
+++ /dev/null
@@ -1,7 +0,0 @@
-// 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 aes
-
-// TODO(rsc): mode implementations go here.