用于EagleEye3.0 规则集漏报和误报测试的示例项目,项目收集于github和gitee
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/*
///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
// Name: codec.cpp
// Purpose:
// Author: Ulrich Telle
// Modified by:
// Created: 2006-12-06
// RCS-ID: $$
// Copyright: (c) Ulrich Telle
// Licence: wxWindows licence + RSA Data Security license
///////////////////////////////////////////////////////////////////////////////
/// \file codec.cpp Implementation of MD5, RC4 and AES algorithms
*/
/*
**********************************************************************
** Copyright (C) 1990, RSA Data Security, Inc. All rights reserved. **
** **
** License to copy and use this software is granted provided that **
** it is identified as the "RSA Data Security, Inc. MD5 Message **
** Digest Algorithm" in all material mentioning or referencing this **
** software or this function. **
** **
** License is also granted to make and use derivative works **
** provided that such works are identified as "derived from the RSA **
** Data Security, Inc. MD5 Message Digest Algorithm" in all **
** material mentioning or referencing the derived work. **
** **
** RSA Data Security, Inc. makes no representations concerning **
** either the merchantability of this software or the suitability **
** of this software for any particular purpose. It is provided "as **
** is" without express or implied warranty of any kind. **
** **
** These notices must be retained in any copies of any part of this **
** documentation and/or software. **
**********************************************************************
*/
#include "codec.h"
#ifndef SQLITE_USER_AUTHENTICATION
#if CODEC_TYPE == CODEC_TYPE_AES256
#include "sha2.h"
#include "sha2.c"
#endif
#endif
/*
// ----------------
// MD5 by RSA
// ----------------
// C headers for MD5
*/
#include <sys/types.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#define MD5_HASHBYTES 16
/*
/// Structure representing an MD5 context while ecrypting. (For internal use only)
*/
typedef struct MD5Context
{
unsigned int buf[4];
unsigned int bits[2];
unsigned char in[64];
} MD5_CTX;
static void MD5Init(MD5_CTX *context);
static void MD5Update(MD5_CTX *context, unsigned char *buf, unsigned len);
static void MD5Final(unsigned char digest[MD5_HASHBYTES], MD5_CTX *context);
static void MD5Transform(unsigned int buf[4], unsigned int in[16]);
static void byteReverse(unsigned char *buf, unsigned longs);
/*
* Note: this code is harmless on little-endian machines.
*/
static void byteReverse(unsigned char *buf, unsigned longs)
{
static int littleEndian = -1;
if (littleEndian < 0)
{
/* Are we little or big endian? This method is from Harbison & Steele. */
union
{
long l;
char c[sizeof(long)];
} u;
u.l = 1;
littleEndian = (u.c[0] == 1) ? 1 : 0;
}
if (littleEndian != 1)
{
unsigned int t;
do
{
t = (unsigned int) ((unsigned) buf[3] << 8 | buf[2]) << 16 |
((unsigned) buf[1] << 8 | buf[0]);
*(unsigned int *) buf = t;
buf += 4;
}
while (--longs);
}
}
#if 0
static char* MD5End(MD5_CTX *, char *);
static char* MD5End(MD5_CTX *ctx, char *buf)
{
int i;
unsigned char digest[MD5_HASHBYTES];
char hex[]="0123456789abcdef";
if (!buf)
{
buf = (char *)malloc(33);
}
if (!buf)
{
return 0;
}
MD5Final(digest,ctx);
for (i=0;i<MD5_HASHBYTES;i++)
{
buf[i+i] = hex[digest[i] >> 4];
buf[i+i+1] = hex[digest[i] & 0x0f];
}
buf[i+i] = '\0';
return buf;
}
#endif
/*
* Final wrapup - pad to 64-byte boundary with the bit pattern
* 1 0* (64-bit count of bits processed, MSB-first)
*/
static void MD5Final(unsigned char digest[16], MD5_CTX *ctx)
{
unsigned count;
unsigned char *p;
/* Compute number of bytes mod 64 */
count = (ctx->bits[0] >> 3) & 0x3F;
/* Set the first char of padding to 0x80. This is safe since there is
always at least one byte free */
p = ctx->in + count;
*p++ = 0x80;
/* Bytes of padding needed to make 64 bytes */
count = 64 - 1 - count;
/* Pad out to 56 mod 64 */
if (count < 8)
{
/* Two lots of padding: Pad the first block to 64 bytes */
memset(p, 0, count);
byteReverse(ctx->in, 16);
MD5Transform(ctx->buf, (unsigned int *) ctx->in);
/* Now fill the next block with 56 bytes */
memset(ctx->in, 0, 56);
}
else
{
/* Pad block to 56 bytes */
memset(p, 0, count - 8);
}
byteReverse(ctx->in, 14);
/* Append length in bits and transform */
((unsigned int *) ctx->in)[14] = ctx->bits[0];
((unsigned int *) ctx->in)[15] = ctx->bits[1];
MD5Transform(ctx->buf, (unsigned int *) ctx->in);
byteReverse((unsigned char *) ctx->buf, 4);
memcpy(digest, ctx->buf, 16);
memset((char *) ctx, 0, sizeof(ctx)); /* In case it's sensitive */
}
static void MD5Init(MD5_CTX *ctx)
{
ctx->buf[0] = 0x67452301;
ctx->buf[1] = 0xefcdab89;
ctx->buf[2] = 0x98badcfe;
ctx->buf[3] = 0x10325476;
ctx->bits[0] = 0;
ctx->bits[1] = 0;
}
static void MD5Update(MD5_CTX *ctx, unsigned char *buf, unsigned len)
{
unsigned int t;
/* Update bitcount */
t = ctx->bits[0];
if ((ctx->bits[0] = t + ((unsigned int) len << 3)) < t)
{
ctx->bits[1]++; /* Carry from low to high */
}
ctx->bits[1] += len >> 29;
t = (t >> 3) & 0x3f; /* Bytes already in shsInfo->data */
/* Handle any leading odd-sized chunks */
if (t)
{
unsigned char *p = (unsigned char *) ctx->in + t;
t = 64 - t;
if (len < t)
{
memcpy(p, buf, len);
return;
}
memcpy(p, buf, t);
byteReverse(ctx->in, 16);
MD5Transform(ctx->buf, (unsigned int *) ctx->in);
buf += t;
len -= t;
}
/* Process data in 64-byte chunks */
while (len >= 64)
{
memcpy(ctx->in, buf, 64);
byteReverse(ctx->in, 16);
MD5Transform(ctx->buf, (unsigned int *) ctx->in);
buf += 64;
len -= 64;
}
/* Handle any remaining bytes of data. */
memcpy(ctx->in, buf, len);
}
/* #define F1(x, y, z) (x & y | ~x & z) */
#define F1(x, y, z) (z ^ (x & (y ^ z)))
#define F2(x, y, z) F1(z, x, y)
#define F3(x, y, z) (x ^ y ^ z)
#define F4(x, y, z) (y ^ (x | ~z))
/* This is the central step in the MD5 algorithm. */
#define MD5STEP(f, w, x, y, z, data, s) \
( w += f(x, y, z) + data, w = w<<s | w>>(32-s), w += x )
/*
* The core of the MD5 algorithm, this alters an existing MD5 hash to
* reflect the addition of 16 longwords of new data. MD5Update blocks
* the data and converts bytes into longwords for this routine.
*/
static void MD5Transform(unsigned int buf[4], unsigned int in[16])
{
register unsigned int a, b, c, d;
a = buf[0];
b = buf[1];
c = buf[2];
d = buf[3];
MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
buf[0] += a;
buf[1] += b;
buf[2] += c;
buf[3] += d;
}
/*
// ---------------------------
// RC4 implementation
// ---------------------------
*/
/**
* RC4 is the standard encryption algorithm used in PDF format
*/
void
CodecRC4(Codec* codec, unsigned char* key, int keylen,
unsigned char* textin, int textlen,
unsigned char* textout)
{
int i;
int j;
int t;
unsigned char rc4[256];
int a = 0;
int b = 0;
unsigned char k;
for (i = 0; i < 256; i++)
{
rc4[i] = i;
}
j = 0;
for (i = 0; i < 256; i++)
{
t = rc4[i];
j = (j + t + key[i % keylen]) % 256;
rc4[i] = rc4[j];
rc4[j] = t;
}
for (i = 0; i < textlen; i++)
{
a = (a + 1) % 256;
t = rc4[a];
b = (b + t) % 256;
rc4[a] = rc4[b];
rc4[b] = t;
k = rc4[(rc4[a] + rc4[b]) % 256];
textout[i] = textin[i] ^ k;
}
}
void
CodecGetMD5Binary(Codec* codec, unsigned char* data, int length, unsigned char* digest)
{
MD5_CTX ctx;
MD5Init(&ctx);
MD5Update(&ctx, data, length);
MD5Final(digest,&ctx);
}
#if CODEC_TYPE == CODEC_TYPE_AES256
void
CodecGetSHABinary(Codec* codec, unsigned char* data, int length, unsigned char* digest)
{
sha256(data, (unsigned int) length, digest);
}
#endif
#define MODMULT(a, b, c, m, s) q = s / a; s = b * (s - a * q) - c * q; if (s < 0) s += m
void
CodecGenerateInitialVector(Codec* codec, int seed, unsigned char iv[16])
{
unsigned char initkey[16];
int j, q;
int z = seed + 1;
for (j = 0; j < 4; j++)
{
MODMULT(52774, 40692, 3791, 2147483399L, z);
initkey[4*j+0] = 0xff & z;
initkey[4*j+1] = 0xff & (z >> 8);
initkey[4*j+2] = 0xff & (z >> 16);
initkey[4*j+3] = 0xff & (z >> 24);
}
CodecGetMD5Binary(codec, (unsigned char*) initkey, 16, iv);
}
void
CodecAES(Codec* codec, int page, int encrypt, unsigned char encryptionKey[KEYLENGTH],
unsigned char* datain, int datalen, unsigned char* dataout)
{
unsigned char initial[16];
unsigned char pagekey[KEYLENGTH];
unsigned char nkey[KEYLENGTH+4+4];
int keyLength = KEYLENGTH;
int nkeylen = keyLength + 4 + 4;
int j;
int direction = (encrypt) ? RIJNDAEL_Direction_Encrypt : RIJNDAEL_Direction_Decrypt;
int len = 0;
for (j = 0; j < keyLength; j++)
{
nkey[j] = encryptionKey[j];
}
nkey[keyLength+0] = 0xff & page;
nkey[keyLength+1] = 0xff & (page >> 8);
nkey[keyLength+2] = 0xff & (page >> 16);
nkey[keyLength+3] = 0xff & (page >> 24);
/* AES encryption needs some 'salt' */
nkey[keyLength+4] = 0x73;
nkey[keyLength+5] = 0x41;
nkey[keyLength+6] = 0x6c;
nkey[keyLength+7] = 0x54;
#if CODEC_TYPE == CODEC_TYPE_AES256
CodecGetSHABinary(codec, nkey, nkeylen, pagekey);
#else
CodecGetMD5Binary(codec, nkey, nkeylen, pagekey);
#endif
CodecGenerateInitialVector(codec, page, initial);
#if CODEC_TYPE == CODEC_TYPE_AES256
RijndaelInit(codec->m_aes, RIJNDAEL_Direction_Mode_CBC, direction, pagekey, RIJNDAEL_Direction_KeyLength_Key32Bytes, initial);
#else
RijndaelInit(codec->m_aes, RIJNDAEL_Direction_Mode_CBC, direction, pagekey, RIJNDAEL_Direction_KeyLength_Key16Bytes, initial);
#endif
if (encrypt)
{
len = RijndaelBlockEncrypt(codec->m_aes, datain, datalen*8, dataout);
}
else
{
len = RijndaelBlockDecrypt(codec->m_aes, datain, datalen*8, dataout);
}
/* It is a good idea to check the error code */
if (len < 0)
{
/* AES: Error on encrypting. */
}
}
static unsigned char padding[] =
"\x28\xBF\x4E\x5E\x4E\x75\x8A\x41\x64\x00\x4E\x56\xFF\xFA\x01\x08\x2E\x2E\x00\xB6\xD0\x68\x3E\x80\x2F\x0C\xA9\xFE\x64\x53\x69\x7A";
void
CodecInit(Codec* codec)
{
codec->m_isEncrypted = 0;
codec->m_hasReadKey = 0;
codec->m_hasWriteKey = 0;
codec->m_aes = (Rijndael*) sqlite3_malloc(sizeof(Rijndael));
RijndaelCreate(codec->m_aes);
}
void
CodecTerm(Codec* codec)
{
sqlite3_free(codec->m_aes);
}
void
CodecSetIsEncrypted(Codec* codec, int isEncrypted)
{
codec->m_isEncrypted = isEncrypted;
}
void
CodecSetHasReadKey(Codec* codec, int hasReadKey)
{
codec->m_hasReadKey = hasReadKey;
}
void
CodecSetHasWriteKey(Codec* codec, int hasWriteKey)
{
codec->m_hasWriteKey = hasWriteKey;
}
void
CodecSetBtree(Codec* codec, Btree* bt)
{
codec->m_bt = bt;
}
int
CodecIsEncrypted(Codec* codec)
{
return codec->m_isEncrypted;
}
int
CodecHasReadKey(Codec* codec)
{
return codec->m_hasReadKey;
}
int
CodecHasWriteKey(Codec* codec)
{
return codec->m_hasWriteKey;
}
Btree*
CodecGetBtree(Codec* codec)
{
return codec->m_bt;
}
unsigned char*
CodecGetPageBuffer(Codec* codec)
{
return &codec->m_page[4];
}
void
CodecCopy(Codec* codec, Codec* other)
{
int j;
codec->m_isEncrypted = other->m_isEncrypted;
codec->m_hasReadKey = other->m_hasReadKey;
codec->m_hasWriteKey = other->m_hasWriteKey;
for (j = 0; j < KEYLENGTH; j++)
{
codec->m_readKey[j] = other->m_readKey[j];
codec->m_writeKey[j] = other->m_writeKey[j];
}
codec->m_bt = other->m_bt;
RijndaelInvalidate(codec->m_aes);
}
void
CodecCopyKey(Codec* codec, int read2write)
{
int j;
if (read2write)
{
for (j = 0; j < KEYLENGTH; j++)
{
codec->m_writeKey[j] = codec->m_readKey[j];
}
}
else
{
for (j = 0; j < KEYLENGTH; j++)
{
codec->m_readKey[j] = codec->m_writeKey[j];
}
}
}
void
CodecPadPassword(Codec* codec, char* password, int pswdlen, unsigned char pswd[32])
{
int j;
int p = 0;
int m = pswdlen;
if (m > 32) m = 32;
for (j = 0; j < m; j++)
{
pswd[p++] = (unsigned char) password[j];
}
for (j = 0; p < 32 && j < 32; j++)
{
pswd[p++] = padding[j];
}
}
void
CodecGenerateReadKey(Codec* codec, char* userPassword, int passwordLength)
{
CodecGenerateEncryptionKey(codec, userPassword, passwordLength, codec->m_readKey);
}
void
CodecGenerateWriteKey(Codec* codec, char* userPassword, int passwordLength)
{
CodecGenerateEncryptionKey(codec, userPassword, passwordLength, codec->m_writeKey);
}
void
CodecGenerateEncryptionKey(Codec* codec, char* userPassword, int passwordLength,
unsigned char encryptionKey[KEYLENGTH])
{
#if CODEC_TYPE == CODEC_TYPE_AES256
unsigned char userPad[32];
unsigned char digest[KEYLENGTH];
int keyLength = KEYLENGTH;
int k;
/* Pad password */
CodecPadPassword(codec, userPassword, passwordLength, userPad);
sha256(userPad, 32, digest);
for (k = 0; k < CODEC_SHA_ITER; ++k)
{
sha256(digest, KEYLENGTH, digest);
}
memcpy(encryptionKey, digest, keyLength);
#else
unsigned char userPad[32];
unsigned char ownerPad[32];
unsigned char ownerKey[32];
unsigned char mkey[MD5_HASHBYTES];
unsigned char digest[MD5_HASHBYTES];
int keyLength = MD5_HASHBYTES;
int i, j, k;
MD5_CTX ctx;
/* Pad passwords */
CodecPadPassword(codec, userPassword, passwordLength, userPad);
CodecPadPassword(codec, "", 0, ownerPad);
/* Compute owner key */
MD5Init(&ctx);
MD5Update(&ctx, ownerPad, 32);
MD5Final(digest,&ctx);
/* only use for the input as many bit as the key consists of */
for (k = 0; k < 50; ++k)
{
MD5Init(&ctx);
MD5Update(&ctx, digest, keyLength);
MD5Final(digest,&ctx);
}
memcpy(ownerKey, userPad, 32);
for (i = 0; i < 20; ++i)
{
for (j = 0; j < keyLength ; ++j)
{
mkey[j] = (digest[j] ^ i);
}
CodecRC4(codec, mkey, keyLength, ownerKey, 32, ownerKey);
}
/* Compute encryption key */
MD5Init(&ctx);
MD5Update(&ctx, userPad, 32);
MD5Update(&ctx, ownerKey, 32);
MD5Final(digest,&ctx);
/* only use the really needed bits as input for the hash */
for (k = 0; k < 50; ++k)
{
MD5Init(&ctx);
MD5Update(&ctx, digest, keyLength);
MD5Final(digest, &ctx);
}
memcpy(encryptionKey, digest, keyLength);
#endif
}
void
CodecEncrypt(Codec* codec, int page, unsigned char* data, int len, int useWriteKey)
{
#ifdef WXSQLITE3_USE_OLD_ENCRYPTION_SCHEME
/* Use the previous encryption scheme */
unsigned char* key = (useWriteKey) ? codec->m_writeKey : codec->m_readKey;
CodecAES(codec, page, 1, key, data, len, data);
#else
unsigned char dbHeader[8];
int offset = 0;
unsigned char* key = (useWriteKey) ? codec->m_writeKey : codec->m_readKey;
if (page == 1)
{
/* Save the header bytes remaining unencrypted */
memcpy(dbHeader, data+16, 8);
offset = 16;
CodecAES(codec, page, 1, key, data, 16, data);
}
CodecAES(codec, page, 1, key, data+offset, len-offset, data+offset);
if (page == 1)
{
/* Move the encrypted header bytes 16..23 to a safe position */
memcpy(data+8, data+16, 8);
/* Restore the unencrypted header bytes 16..23 */
memcpy(data+16, dbHeader, 8);
}
#endif
}
void
CodecDecrypt(Codec* codec, int page, unsigned char* data, int len)
{
#ifdef WXSQLITE3_USE_OLD_ENCRYPTION_SCHEME
/* Use the previous encryption scheme */
CodecAES(codec, page, 0, codec->m_readKey, data, len, data);
#else
unsigned char dbHeader[8];
int dbPageSize;
int offset = 0;
if (page == 1)
{
/* Save (unencrypted) header bytes 16..23 */
memcpy(dbHeader, data+16, 8);
/* Determine page size */
dbPageSize = (dbHeader[0] << 8) | (dbHeader[1] << 16);
/* Check whether the database header is valid */
/* If yes, the database follows the new encryption scheme, otherwise use the previous encryption scheme */
if ((dbPageSize >= 512) && (dbPageSize <= SQLITE_MAX_PAGE_SIZE) && (((dbPageSize-1) & dbPageSize) == 0) &&
(dbHeader[5] == 0x40) && (dbHeader[6] == 0x20) && (dbHeader[7] == 0x20))
{
/* Restore encrypted bytes 16..23 for new encryption scheme */
memcpy(data+16, data+8, 8);
offset = 16;
}
}
CodecAES(codec, page, 0, codec->m_readKey, data+offset, len-offset, data+offset);
if (page == 1 && offset != 0)
{
/* Verify the database header */
if (memcmp(dbHeader, data+16, 8) == 0)
{
memcpy(data, SQLITE_FILE_HEADER, 16);
}
}
#endif
}