Files
Bento4/Source/C++/Crypto/Ap4Hmac.cpp
2010-11-01 08:51:41 +00:00

332 lines
11 KiB
C++

/*****************************************************************
|
| AP4 - HMAC Algorithms
|
| Copyright 2002-2009 Axiomatic Systems, LLC
|
|
| This file is part of Bento4/AP4 (MP4 Atom Processing Library).
|
| Unless you have obtained Bento4 under a difference license,
| this version of Bento4 is Bento4|GPL.
| Bento4|GPL is free software; you can redistribute it and/or modify
| it under the terms of the GNU General Public License as published by
| the Free Software Foundation; either version 2, or (at your option)
| any later version.
|
| Bento4|GPL is distributed in the hope that it will be useful,
| but WITHOUT ANY WARRANTY; without even the implied warranty of
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
| GNU General Public License for more details.
|
| You should have received a copy of the GNU General Public License
| along with Bento4|GPL; see the file COPYING. If not, write to the
| Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA
| 02111-1307, USA.
|
****************************************************************/
/*
Portions of this code are based on the code of LibTomCrypt
that was released into public domain by Tom St Denis.
*/
/*----------------------------------------------------------------------
| includes
+---------------------------------------------------------------------*/
#include "Ap4Hmac.h"
#include "Ap4Utils.h"
/*----------------------------------------------------------------------
| constants
+---------------------------------------------------------------------*/
#define AP4_SHA256_BLOCK_SIZE 64
static const AP4_UI32 AP4_Sha256_K[64] = {
0x428a2f98UL, 0x71374491UL, 0xb5c0fbcfUL, 0xe9b5dba5UL, 0x3956c25bUL,
0x59f111f1UL, 0x923f82a4UL, 0xab1c5ed5UL, 0xd807aa98UL, 0x12835b01UL,
0x243185beUL, 0x550c7dc3UL, 0x72be5d74UL, 0x80deb1feUL, 0x9bdc06a7UL,
0xc19bf174UL, 0xe49b69c1UL, 0xefbe4786UL, 0x0fc19dc6UL, 0x240ca1ccUL,
0x2de92c6fUL, 0x4a7484aaUL, 0x5cb0a9dcUL, 0x76f988daUL, 0x983e5152UL,
0xa831c66dUL, 0xb00327c8UL, 0xbf597fc7UL, 0xc6e00bf3UL, 0xd5a79147UL,
0x06ca6351UL, 0x14292967UL, 0x27b70a85UL, 0x2e1b2138UL, 0x4d2c6dfcUL,
0x53380d13UL, 0x650a7354UL, 0x766a0abbUL, 0x81c2c92eUL, 0x92722c85UL,
0xa2bfe8a1UL, 0xa81a664bUL, 0xc24b8b70UL, 0xc76c51a3UL, 0xd192e819UL,
0xd6990624UL, 0xf40e3585UL, 0x106aa070UL, 0x19a4c116UL, 0x1e376c08UL,
0x2748774cUL, 0x34b0bcb5UL, 0x391c0cb3UL, 0x4ed8aa4aUL, 0x5b9cca4fUL,
0x682e6ff3UL, 0x748f82eeUL, 0x78a5636fUL, 0x84c87814UL, 0x8cc70208UL,
0x90befffaUL, 0xa4506cebUL, 0xbef9a3f7UL, 0xc67178f2UL
};
/*----------------------------------------------------------------------
| AP4_DigestSha256
+---------------------------------------------------------------------*/
class AP4_DigestSha256
{
public:
AP4_DigestSha256();
virtual ~AP4_DigestSha256() {}
// AP4_Hmac methods
virtual AP4_Result Update(const AP4_UI08* data, AP4_Size data_size);
virtual AP4_Result Final(AP4_DataBuffer& digest);
private:
// methods
void CompressBlock(const AP4_UI08* block);
// members
AP4_UI64 m_Length;
AP4_UI32 m_Pending;
AP4_UI32 m_State[8];
AP4_UI08 m_Buffer[64];
};
/*----------------------------------------------------------------------
| AP4_HmacSha256
|
| compute SHA256(key XOR opad, SHA256(key XOR ipad, data))
| key is the MAC key
| ipad is the byte 0x36 repeated 64 times
| opad is the byte 0x5c repeated 64 times
| and data is the data to authenticate
|
+---------------------------------------------------------------------*/
class AP4_HmacSha256 : public AP4_Hmac
{
public:
AP4_HmacSha256(const AP4_UI08* key, AP4_Size key_size);
// AP4_Hmac methods
virtual AP4_Result Update(const AP4_UI08* data, AP4_Size data_size) {
return m_InnerDigest.Update(data, data_size);
}
virtual AP4_Result Final(AP4_DataBuffer& buffer);
private:
AP4_DigestSha256 m_InnerDigest;
AP4_DigestSha256 m_OuterDigest;
};
/*----------------------------------------------------------------------
| AP4_DigestSha256::AP4_DigestSha256
+---------------------------------------------------------------------*/
AP4_DigestSha256::AP4_DigestSha256() :
m_Length(0),
m_Pending(0)
{
m_State[0] = 0x6A09E667UL;
m_State[1] = 0xBB67AE85UL;
m_State[2] = 0x3C6EF372UL;
m_State[3] = 0xA54FF53AUL;
m_State[4] = 0x510E527FUL;
m_State[5] = 0x9B05688CUL;
m_State[6] = 0x1F83D9ABUL;
m_State[7] = 0x5BE0CD19UL;
AP4_SetMemory(m_Buffer, 0, sizeof(m_Buffer));
}
/*----------------------------------------------------------------------
| local macros
+---------------------------------------------------------------------*/
#define AP4_Sha256_RORc(x, y) \
( ((((unsigned long) (x) & 0xFFFFFFFFUL) >> (unsigned long) ((y) & 31)) | \
((unsigned long) (x) << (unsigned long) (32 - ((y) & 31)))) & 0xFFFFFFFFUL)
#define AP4_Sha256_Ch(x,y,z) (z ^ (x & (y ^ z)))
#define AP4_Sha256_Maj(x,y,z) (((x | y) & z) | (x & y))
#define AP4_Sha256_S(x, n) AP4_Sha256_RORc((x), (n))
#define AP4_Sha256_R(x, n) (((x)&0xFFFFFFFFUL)>>(n))
#define AP4_Sha256_Sigma0(x) (AP4_Sha256_S(x, 2) ^ AP4_Sha256_S(x, 13) ^ AP4_Sha256_S(x, 22))
#define AP4_Sha256_Sigma1(x) (AP4_Sha256_S(x, 6) ^ AP4_Sha256_S(x, 11) ^ AP4_Sha256_S(x, 25))
#define AP4_Sha256_Gamma0(x) (AP4_Sha256_S(x, 7) ^ AP4_Sha256_S(x, 18) ^ AP4_Sha256_R(x, 3))
#define AP4_Sha256_Gamma1(x) (AP4_Sha256_S(x, 17) ^ AP4_Sha256_S(x, 19) ^ AP4_Sha256_R(x, 10))
/*----------------------------------------------------------------------
| AP4_DigestSha256::CompressBlock
+---------------------------------------------------------------------*/
void
AP4_DigestSha256::CompressBlock(const AP4_UI08* block)
{
AP4_UI32 S[8], W[64];
/* copy the state into S */
for (unsigned int i = 0; i < 8; i++) {
S[i] = m_State[i];
}
/* copy the 512-bit block into W[0..15] */
for (unsigned int i = 0; i < 16; i++) {
W[i] = AP4_BytesToUInt32BE(&block[4*i]);
}
/* fill W[16..63] */
for (unsigned int i = 16; i < AP4_SHA256_BLOCK_SIZE; i++) {
W[i] = AP4_Sha256_Gamma1(W[i-2]) + W[i-7] + AP4_Sha256_Gamma0(W[i-15]) + W[i-16];
}
/* compress */
AP4_UI32 t, t0, t1;
for (unsigned int i = 0; i < AP4_SHA256_BLOCK_SIZE; ++i) {
t0 = S[7] + AP4_Sha256_Sigma1(S[4]) + AP4_Sha256_Ch(S[4], S[5], S[6]) + AP4_Sha256_K[i] + W[i];
t1 = AP4_Sha256_Sigma0(S[0]) + AP4_Sha256_Maj(S[0], S[1], S[2]);
S[3] += t0;
S[7] = t0 + t1;
t = S[7]; S[7] = S[6]; S[6] = S[5]; S[5] = S[4];
S[4] = S[3]; S[3] = S[2]; S[2] = S[1]; S[1] = S[0]; S[0] = t;
}
/* feedback */
for (unsigned int i = 0; i < 8; i++) {
m_State[i] = m_State[i] + S[i];
}
}
/*----------------------------------------------------------------------
| AP4_DigestSha256::Update
+---------------------------------------------------------------------*/
AP4_Result
AP4_DigestSha256::Update(const AP4_UI08* data, AP4_Size data_size)
{
while (data_size > 0) {
if (m_Pending == 0 && data_size >= AP4_SHA256_BLOCK_SIZE) {
CompressBlock(data);
m_Length += AP4_SHA256_BLOCK_SIZE * 8;
data += AP4_SHA256_BLOCK_SIZE;
data_size -= AP4_SHA256_BLOCK_SIZE;
} else {
unsigned int chunk = data_size;
if (chunk > (AP4_SHA256_BLOCK_SIZE - m_Pending)) {
chunk = AP4_SHA256_BLOCK_SIZE - m_Pending;
}
AP4_CopyMemory(&m_Buffer[m_Pending], data, chunk);
m_Pending += chunk;
data += chunk;
data_size -= chunk;
if (m_Pending == AP4_SHA256_BLOCK_SIZE) {
CompressBlock(m_Buffer);
m_Length += 8 * AP4_SHA256_BLOCK_SIZE;
m_Pending = 0;
}
}
}
return AP4_SUCCESS;
}
/*----------------------------------------------------------------------
| AP4_DigestSha256::Final
+---------------------------------------------------------------------*/
AP4_Result
AP4_DigestSha256::Final(AP4_DataBuffer& digest)
{
/* increase the length of the message */
m_Length += m_Pending * 8;
/* append the '1' bit */
m_Buffer[m_Pending++] = 0x80;
/* if the length is currently above 56 bytes we append zeros
* then compress. Then we can fall back to padding zeros and length
* encoding like normal.
*/
if (m_Pending > 56) {
while (m_Pending < 64) {
m_Buffer[m_Pending++] = 0;
}
CompressBlock(m_Buffer);
m_Pending = 0;
}
/* pad upto 56 bytes of zeroes */
while (m_Pending < 56) {
m_Buffer[m_Pending++] = 0;
}
/* store length */
AP4_BytesFromUInt64BE(&m_Buffer[56], m_Length);
CompressBlock(m_Buffer);
/* copy output */
digest.SetDataSize(32);
AP4_UI08* out = digest.UseData();
for (unsigned int i = 0; i < 8; i++) {
AP4_BytesFromUInt32BE(out, m_State[i]);
out += 4;
}
return AP4_SUCCESS;
}
/*----------------------------------------------------------------------
| AP4_HmacSha256::AP4_HmacSha256
+---------------------------------------------------------------------*/
AP4_HmacSha256::AP4_HmacSha256(const AP4_UI08* key, AP4_Size key_size)
{
AP4_UI08 workspace[AP4_SHA256_BLOCK_SIZE];
/* if the key is larger than the block size, use a digest of the key */
if (key_size > AP4_SHA256_BLOCK_SIZE) {
AP4_DigestSha256 kdigest;
kdigest.Update(key, key_size);
AP4_DataBuffer hk;
kdigest.Final(hk);
key = hk.GetData();
key_size = hk.GetDataSize();
}
/* compute key XOR ipad */
for (unsigned int i = 0; i < key_size; i++) {
workspace[i] = key[i] ^ 0x36;
}
for (unsigned int i = key_size; i < AP4_SHA256_BLOCK_SIZE; i++) {
workspace[i] = 0x36;
}
/* start the inner digest with (key XOR ipad) */
m_InnerDigest.Update(workspace, AP4_SHA256_BLOCK_SIZE);
/* compute key XOR opad */
for (unsigned int i = 0; i < key_size; i++) {
workspace[i] = key[i] ^ 0x5c;
}
for (unsigned int i = key_size; i < AP4_SHA256_BLOCK_SIZE; i++) {
workspace[i] = 0x5c;
}
/* start the outer digest with (key XOR opad) */
m_OuterDigest.Update(workspace, AP4_SHA256_BLOCK_SIZE);
}
/*----------------------------------------------------------------------
| AP4_HmacSha256::Final
+---------------------------------------------------------------------*/
AP4_Result
AP4_HmacSha256::Final(AP4_DataBuffer& mac)
{
/* finish the outer digest with the value of the inner digest */
AP4_DataBuffer inner;
m_InnerDigest.Final(inner);
m_OuterDigest.Update(inner.GetData(), inner.GetDataSize());
/* return the value of the outer digest */
return m_OuterDigest.Final(mac);
}
/*----------------------------------------------------------------------
| AP4_Hmac::Create
+---------------------------------------------------------------------*/
AP4_Result
AP4_Hmac::Create(Algorithm algorithm,
const AP4_UI08* key,
AP4_Size key_size,
AP4_Hmac*& hmac)
{
switch (algorithm) {
case SHA256: hmac = new AP4_HmacSha256(key, key_size); return AP4_SUCCESS;
default: hmac = NULL; return AP4_ERROR_NOT_SUPPORTED;
}
}