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DEFINITIONS
This source file includes following definitions.
- makeFileKey
- makeFileKey2
- reset
- getChar
- lookChar
- isBinary
- rc4InitKey
- rc4DecryptByte
- subWord
- rotWord
- invSubBytes
- invShiftRows
- mul09
- mul0b
- mul0d
- mul0e
- invMixColumns
- invMixColumnsW
- addRoundKey
- aesKeyExpansion
- aesDecryptBlock
- rotateLeft
- md5Round1
- md5Round2
- md5Round3
- md5Round4
- md5
//========================================================================
//
// Decrypt.cc
//
// Copyright 1996-2003 Glyph & Cog, LLC
//
//========================================================================
#include <aconf.h>
#ifdef USE_GCC_PRAGMAS
#pragma implementation
#endif
#include <string.h>
#include "gmem.h"
#include "Decrypt.h"
static void rc4InitKey(Guchar *key, int keyLen, Guchar *state);
static Guchar rc4DecryptByte(Guchar *state, Guchar *x, Guchar *y, Guchar c);
static void aesKeyExpansion(DecryptAESState *s,
Guchar *objKey, int objKeyLen);
static void aesDecryptBlock(DecryptAESState *s, Guchar *in, GBool last);
static void md5(Guchar *msg, int msgLen, Guchar *digest);
static Guchar passwordPad[32] = {
0x28, 0xbf, 0x4e, 0x5e, 0x4e, 0x75, 0x8a, 0x41,
0x64, 0x00, 0x4e, 0x56, 0xff, 0xfa, 0x01, 0x08,
0x2e, 0x2e, 0x00, 0xb6, 0xd0, 0x68, 0x3e, 0x80,
0x2f, 0x0c, 0xa9, 0xfe, 0x64, 0x53, 0x69, 0x7a
};
//------------------------------------------------------------------------
// Decrypt
//------------------------------------------------------------------------
GBool Decrypt::makeFileKey(int encVersion, int encRevision, int keyLength,
GString *ownerKey, GString *userKey,
int permissions, GString *fileID,
GString *ownerPassword, GString *userPassword,
Guchar *fileKey, GBool encryptMetadata,
GBool *ownerPasswordOk) {
Guchar test[32], test2[32];
GString *userPassword2;
Guchar fState[256];
Guchar tmpKey[16];
Guchar fx, fy;
int len, i, j;
// try using the supplied owner password to generate the user password
*ownerPasswordOk = gFalse;
if (ownerPassword) {
len = ownerPassword->getLength();
if (len < 32) {
memcpy(test, ownerPassword->getCString(), len);
memcpy(test + len, passwordPad, 32 - len);
} else {
memcpy(test, ownerPassword->getCString(), 32);
}
md5(test, 32, test);
if (encRevision == 3) {
for (i = 0; i < 50; ++i) {
md5(test, 16, test);
}
}
if (encRevision == 2) {
rc4InitKey(test, keyLength, fState);
fx = fy = 0;
for (i = 0; i < 32; ++i) {
test2[i] = rc4DecryptByte(fState, &fx, &fy, ownerKey->getChar(i));
}
} else {
memcpy(test2, ownerKey->getCString(), 32);
for (i = 19; i >= 0; --i) {
for (j = 0; j < keyLength; ++j) {
tmpKey[j] = test[j] ^ i;
}
rc4InitKey(tmpKey, keyLength, fState);
fx = fy = 0;
for (j = 0; j < 32; ++j) {
test2[j] = rc4DecryptByte(fState, &fx, &fy, test2[j]);
}
}
}
userPassword2 = new GString((char *)test2, 32);
if (makeFileKey2(encVersion, encRevision, keyLength, ownerKey, userKey,
permissions, fileID, userPassword2, fileKey,
encryptMetadata)) {
*ownerPasswordOk = gTrue;
delete userPassword2;
return gTrue;
}
delete userPassword2;
}
// try using the supplied user password
return makeFileKey2(encVersion, encRevision, keyLength, ownerKey, userKey,
permissions, fileID, userPassword, fileKey,
encryptMetadata);
}
GBool Decrypt::makeFileKey2(int encVersion, int encRevision, int keyLength,
GString *ownerKey, GString *userKey,
int permissions, GString *fileID,
GString *userPassword, Guchar *fileKey,
GBool encryptMetadata) {
Guchar *buf;
Guchar test[32];
Guchar fState[256];
Guchar tmpKey[16];
Guchar fx, fy;
int len, i, j;
GBool ok;
// generate file key
buf = (Guchar *)gmalloc(72 + fileID->getLength());
if (userPassword) {
len = userPassword->getLength();
if (len < 32) {
memcpy(buf, userPassword->getCString(), len);
memcpy(buf + len, passwordPad, 32 - len);
} else {
memcpy(buf, userPassword->getCString(), 32);
}
} else {
memcpy(buf, passwordPad, 32);
}
memcpy(buf + 32, ownerKey->getCString(), 32);
buf[64] = permissions & 0xff;
buf[65] = (permissions >> 8) & 0xff;
buf[66] = (permissions >> 16) & 0xff;
buf[67] = (permissions >> 24) & 0xff;
memcpy(buf + 68, fileID->getCString(), fileID->getLength());
len = 68 + fileID->getLength();
if (!encryptMetadata) {
buf[len++] = 0xff;
buf[len++] = 0xff;
buf[len++] = 0xff;
buf[len++] = 0xff;
}
md5(buf, len, fileKey);
if (encRevision == 3) {
for (i = 0; i < 50; ++i) {
md5(fileKey, keyLength, fileKey);
}
}
// test user password
if (encRevision == 2) {
rc4InitKey(fileKey, keyLength, fState);
fx = fy = 0;
for (i = 0; i < 32; ++i) {
test[i] = rc4DecryptByte(fState, &fx, &fy, userKey->getChar(i));
}
ok = memcmp(test, passwordPad, 32) == 0;
} else if (encRevision == 3) {
memcpy(test, userKey->getCString(), 32);
for (i = 19; i >= 0; --i) {
for (j = 0; j < keyLength; ++j) {
tmpKey[j] = fileKey[j] ^ i;
}
rc4InitKey(tmpKey, keyLength, fState);
fx = fy = 0;
for (j = 0; j < 32; ++j) {
test[j] = rc4DecryptByte(fState, &fx, &fy, test[j]);
}
}
memcpy(buf, passwordPad, 32);
memcpy(buf + 32, fileID->getCString(), fileID->getLength());
md5(buf, 32 + fileID->getLength(), buf);
ok = memcmp(test, buf, 16) == 0;
} else {
ok = gFalse;
}
gfree(buf);
return ok;
}
//------------------------------------------------------------------------
// DecryptStream
//------------------------------------------------------------------------
DecryptStream::DecryptStream(Stream *strA, Guchar *fileKey,
CryptAlgorithm algoA, int keyLength,
int objNum, int objGen):
FilterStream(strA)
{
int n, i;
algo = algoA;
// construct object key
for (i = 0; i < keyLength; ++i) {
objKey[i] = fileKey[i];
}
objKey[keyLength] = objNum & 0xff;
objKey[keyLength + 1] = (objNum >> 8) & 0xff;
objKey[keyLength + 2] = (objNum >> 16) & 0xff;
objKey[keyLength + 3] = objGen & 0xff;
objKey[keyLength + 4] = (objGen >> 8) & 0xff;
if (algo == cryptAES) {
objKey[keyLength + 5] = 0x73; // 's'
objKey[keyLength + 6] = 0x41; // 'A'
objKey[keyLength + 7] = 0x6c; // 'l'
objKey[keyLength + 8] = 0x54; // 'T'
n = keyLength + 9;
} else {
n = keyLength + 5;
}
md5(objKey, n, objKey);
if ((objKeyLength = keyLength + 5) > 16) {
objKeyLength = 16;
}
}
DecryptStream::~DecryptStream() {
delete str;
}
void DecryptStream::reset() {
int i;
str->reset();
switch (algo) {
case cryptRC4:
state.rc4.x = state.rc4.y = 0;
rc4InitKey(objKey, objKeyLength, state.rc4.state);
state.rc4.buf = EOF;
break;
case cryptAES:
aesKeyExpansion(&state.aes, objKey, objKeyLength);
for (i = 0; i < 16; ++i) {
state.aes.cbc[i] = str->getChar();
}
state.aes.bufIdx = 16;
break;
}
}
int DecryptStream::getChar() {
Guchar in[16];
int c, i;
c = EOF; // make gcc happy
switch (algo) {
case cryptRC4:
if (state.rc4.buf == EOF) {
c = str->getChar();
if (c != EOF) {
state.rc4.buf = rc4DecryptByte(state.rc4.state, &state.rc4.x,
&state.rc4.y, (Guchar)c);
}
}
c = state.rc4.buf;
state.rc4.buf = EOF;
break;
case cryptAES:
if (state.aes.bufIdx == 16) {
for (i = 0; i < 16; ++i) {
if ((c = str->getChar()) == EOF) {
return EOF;
}
in[i] = (Guchar)c;
}
aesDecryptBlock(&state.aes, in, str->lookChar() == EOF);
}
if (state.aes.bufIdx == 16) {
c = EOF;
} else {
c = state.aes.buf[state.aes.bufIdx++];
}
break;
}
return c;
}
int DecryptStream::lookChar() {
Guchar in[16];
int c, i;
c = EOF; // make gcc happy
switch (algo) {
case cryptRC4:
if (state.rc4.buf == EOF) {
c = str->getChar();
if (c != EOF) {
state.rc4.buf = rc4DecryptByte(state.rc4.state, &state.rc4.x,
&state.rc4.y, (Guchar)c);
}
}
c = state.rc4.buf;
break;
case cryptAES:
if (state.aes.bufIdx == 16) {
for (i = 0; i < 16; ++i) {
if ((c = str->getChar()) == EOF) {
return EOF;
}
in[i] = c;
}
aesDecryptBlock(&state.aes, in, str->lookChar() == EOF);
}
if (state.aes.bufIdx == 16) {
c = EOF;
} else {
c = state.aes.buf[state.aes.bufIdx];
}
break;
}
return c;
}
GBool DecryptStream::isBinary(GBool last) {
return str->isBinary(last);
}
//------------------------------------------------------------------------
// RC4-compatible decryption
//------------------------------------------------------------------------
static void rc4InitKey(Guchar *key, int keyLen, Guchar *state) {
Guchar index1, index2;
Guchar t;
int i;
for (i = 0; i < 256; ++i)
state[i] = i;
index1 = index2 = 0;
for (i = 0; i < 256; ++i) {
index2 = (key[index1] + state[i] + index2) % 256;
t = state[i];
state[i] = state[index2];
state[index2] = t;
index1 = (index1 + 1) % keyLen;
}
}
static Guchar rc4DecryptByte(Guchar *state, Guchar *x, Guchar *y, Guchar c) {
Guchar x1, y1, tx, ty;
x1 = *x = (*x + 1) % 256;
y1 = *y = (state[*x] + *y) % 256;
tx = state[x1];
ty = state[y1];
state[x1] = ty;
state[y1] = tx;
return c ^ state[(tx + ty) % 256];
}
//------------------------------------------------------------------------
// AES decryption
//------------------------------------------------------------------------
static Guchar sbox[256] = {
0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5, 0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76,
0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0, 0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0,
0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc, 0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15,
0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a, 0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75,
0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0, 0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84,
0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b, 0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf,
0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85, 0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8,
0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5, 0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2,
0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17, 0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73,
0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88, 0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb,
0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c, 0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79,
0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9, 0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08,
0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6, 0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a,
0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e, 0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e,
0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94, 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf,
0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68, 0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16
};
static Guchar invSbox[256] = {
0x52, 0x09, 0x6a, 0xd5, 0x30, 0x36, 0xa5, 0x38, 0xbf, 0x40, 0xa3, 0x9e, 0x81, 0xf3, 0xd7, 0xfb,
0x7c, 0xe3, 0x39, 0x82, 0x9b, 0x2f, 0xff, 0x87, 0x34, 0x8e, 0x43, 0x44, 0xc4, 0xde, 0xe9, 0xcb,
0x54, 0x7b, 0x94, 0x32, 0xa6, 0xc2, 0x23, 0x3d, 0xee, 0x4c, 0x95, 0x0b, 0x42, 0xfa, 0xc3, 0x4e,
0x08, 0x2e, 0xa1, 0x66, 0x28, 0xd9, 0x24, 0xb2, 0x76, 0x5b, 0xa2, 0x49, 0x6d, 0x8b, 0xd1, 0x25,
0x72, 0xf8, 0xf6, 0x64, 0x86, 0x68, 0x98, 0x16, 0xd4, 0xa4, 0x5c, 0xcc, 0x5d, 0x65, 0xb6, 0x92,
0x6c, 0x70, 0x48, 0x50, 0xfd, 0xed, 0xb9, 0xda, 0x5e, 0x15, 0x46, 0x57, 0xa7, 0x8d, 0x9d, 0x84,
0x90, 0xd8, 0xab, 0x00, 0x8c, 0xbc, 0xd3, 0x0a, 0xf7, 0xe4, 0x58, 0x05, 0xb8, 0xb3, 0x45, 0x06,
0xd0, 0x2c, 0x1e, 0x8f, 0xca, 0x3f, 0x0f, 0x02, 0xc1, 0xaf, 0xbd, 0x03, 0x01, 0x13, 0x8a, 0x6b,
0x3a, 0x91, 0x11, 0x41, 0x4f, 0x67, 0xdc, 0xea, 0x97, 0xf2, 0xcf, 0xce, 0xf0, 0xb4, 0xe6, 0x73,
0x96, 0xac, 0x74, 0x22, 0xe7, 0xad, 0x35, 0x85, 0xe2, 0xf9, 0x37, 0xe8, 0x1c, 0x75, 0xdf, 0x6e,
0x47, 0xf1, 0x1a, 0x71, 0x1d, 0x29, 0xc5, 0x89, 0x6f, 0xb7, 0x62, 0x0e, 0xaa, 0x18, 0xbe, 0x1b,
0xfc, 0x56, 0x3e, 0x4b, 0xc6, 0xd2, 0x79, 0x20, 0x9a, 0xdb, 0xc0, 0xfe, 0x78, 0xcd, 0x5a, 0xf4,
0x1f, 0xdd, 0xa8, 0x33, 0x88, 0x07, 0xc7, 0x31, 0xb1, 0x12, 0x10, 0x59, 0x27, 0x80, 0xec, 0x5f,
0x60, 0x51, 0x7f, 0xa9, 0x19, 0xb5, 0x4a, 0x0d, 0x2d, 0xe5, 0x7a, 0x9f, 0x93, 0xc9, 0x9c, 0xef,
0xa0, 0xe0, 0x3b, 0x4d, 0xae, 0x2a, 0xf5, 0xb0, 0xc8, 0xeb, 0xbb, 0x3c, 0x83, 0x53, 0x99, 0x61,
0x17, 0x2b, 0x04, 0x7e, 0xba, 0x77, 0xd6, 0x26, 0xe1, 0x69, 0x14, 0x63, 0x55, 0x21, 0x0c, 0x7d
};
static Guint rcon[11] = {
0x00000000, // unused
0x01000000,
0x02000000,
0x04000000,
0x08000000,
0x10000000,
0x20000000,
0x40000000,
0x80000000,
0x1b000000,
0x36000000
};
static inline Guint subWord(Guint x) {
return (sbox[x >> 24] << 24)
| (sbox[(x >> 16) & 0xff] << 16)
| (sbox[(x >> 8) & 0xff] << 8)
| sbox[x & 0xff];
}
static inline Guint rotWord(Guint x) {
return ((x << 8) & 0xffffffff) | (x >> 24);
}
static inline void invSubBytes(Guchar *state) {
int i;
for (i = 0; i < 16; ++i) {
state[i] = invSbox[state[i]];
}
}
static inline void invShiftRows(Guchar *state) {
Guchar t;
t = state[7];
state[7] = state[6];
state[6] = state[5];
state[5] = state[4];
state[4] = t;
t = state[8];
state[8] = state[10];
state[10] = t;
t = state[9];
state[9] = state[11];
state[11] = t;
t = state[12];
state[12] = state[13];
state[13] = state[14];
state[14] = state[15];
state[15] = t;
}
// {09} \cdot s
static inline Guchar mul09(Guchar s) {
Guchar s2, s4, s8;
s2 = (s & 0x80) ? ((s << 1) ^ 0x1b) : (s << 1);
s4 = (s2 & 0x80) ? ((s2 << 1) ^ 0x1b) : (s2 << 1);
s8 = (s4 & 0x80) ? ((s4 << 1) ^ 0x1b) : (s4 << 1);
return s ^ s8;
}
// {0b} \cdot s
static inline Guchar mul0b(Guchar s) {
Guchar s2, s4, s8;
s2 = (s & 0x80) ? ((s << 1) ^ 0x1b) : (s << 1);
s4 = (s2 & 0x80) ? ((s2 << 1) ^ 0x1b) : (s2 << 1);
s8 = (s4 & 0x80) ? ((s4 << 1) ^ 0x1b) : (s4 << 1);
return s ^ s2 ^ s8;
}
// {0d} \cdot s
static inline Guchar mul0d(Guchar s) {
Guchar s2, s4, s8;
s2 = (s & 0x80) ? ((s << 1) ^ 0x1b) : (s << 1);
s4 = (s2 & 0x80) ? ((s2 << 1) ^ 0x1b) : (s2 << 1);
s8 = (s4 & 0x80) ? ((s4 << 1) ^ 0x1b) : (s4 << 1);
return s ^ s4 ^ s8;
}
// {0e} \cdot s
static inline Guchar mul0e(Guchar s) {
Guchar s2, s4, s8;
s2 = (s & 0x80) ? ((s << 1) ^ 0x1b) : (s << 1);
s4 = (s2 & 0x80) ? ((s2 << 1) ^ 0x1b) : (s2 << 1);
s8 = (s4 & 0x80) ? ((s4 << 1) ^ 0x1b) : (s4 << 1);
return s2 ^ s4 ^ s8;
}
static inline void invMixColumns(Guchar *state) {
int c;
Guchar s0, s1, s2, s3;
for (c = 0; c < 4; ++c) {
s0 = state[c];
s1 = state[4+c];
s2 = state[8+c];
s3 = state[12+c];
state[c] = mul0e(s0) ^ mul0b(s1) ^ mul0d(s2) ^ mul09(s3);
state[4+c] = mul09(s0) ^ mul0e(s1) ^ mul0b(s2) ^ mul0d(s3);
state[8+c] = mul0d(s0) ^ mul09(s1) ^ mul0e(s2) ^ mul0b(s3);
state[12+c] = mul0b(s0) ^ mul0d(s1) ^ mul09(s2) ^ mul0e(s3);
}
}
static inline void invMixColumnsW(Guint *w) {
int c;
Guchar s0, s1, s2, s3;
for (c = 0; c < 4; ++c) {
s0 = w[c] >> 24;
s1 = w[c] >> 16;
s2 = w[c] >> 8;
s3 = w[c];
w[c] = ((mul0e(s0) ^ mul0b(s1) ^ mul0d(s2) ^ mul09(s3)) << 24)
| ((mul09(s0) ^ mul0e(s1) ^ mul0b(s2) ^ mul0d(s3)) << 16)
| ((mul0d(s0) ^ mul09(s1) ^ mul0e(s2) ^ mul0b(s3)) << 8)
| (mul0b(s0) ^ mul0d(s1) ^ mul09(s2) ^ mul0e(s3));
}
}
static inline void addRoundKey(Guchar *state, Guint *w) {
int c;
for (c = 0; c < 4; ++c) {
state[c] ^= w[c] >> 24;
state[4+c] ^= w[c] >> 16;
state[8+c] ^= w[c] >> 8;
state[12+c] ^= w[c];
}
}
static void aesKeyExpansion(DecryptAESState *s,
Guchar *objKey, int objKeyLen) {
Guint temp;
int i, round;
//~ this assumes objKeyLen == 16
for (i = 0; i < 4; ++i) {
s->w[i] = (objKey[4*i] << 24) + (objKey[4*i+1] << 16) +
(objKey[4*i+2] << 8) + objKey[4*i+3];
}
for (i = 4; i < 44; ++i) {
temp = s->w[i-1];
if (!(i & 3)) {
temp = subWord(rotWord(temp)) ^ rcon[i/4];
}
s->w[i] = s->w[i-4] ^ temp;
}
for (round = 1; round <= 9; ++round) {
invMixColumnsW(&s->w[round * 4]);
}
}
static void aesDecryptBlock(DecryptAESState *s, Guchar *in, GBool last) {
int c, round, n, i;
// initial state
for (c = 0; c < 4; ++c) {
s->state[c] = in[4*c];
s->state[4+c] = in[4*c+1];
s->state[8+c] = in[4*c+2];
s->state[12+c] = in[4*c+3];
}
// round 0
addRoundKey(s->state, &s->w[10 * 4]);
// rounds 1-9
for (round = 9; round >= 1; --round) {
invSubBytes(s->state);
invShiftRows(s->state);
invMixColumns(s->state);
addRoundKey(s->state, &s->w[round * 4]);
}
// round 10
invSubBytes(s->state);
invShiftRows(s->state);
addRoundKey(s->state, &s->w[0]);
// CBC
for (c = 0; c < 4; ++c) {
s->buf[4*c] = s->state[c] ^ s->cbc[4*c];
s->buf[4*c+1] = s->state[4+c] ^ s->cbc[4*c+1];
s->buf[4*c+2] = s->state[8+c] ^ s->cbc[4*c+2];
s->buf[4*c+3] = s->state[12+c] ^ s->cbc[4*c+3];
}
// save the input block for the next CBC
for (i = 0; i < 16; ++i) {
s->cbc[i] = in[i];
}
// remove padding
s->bufIdx = 0;
if (last) {
n = s->buf[15];
if(!n || n>16) n=16;
for (i = 15; i >= n; --i) {
s->buf[i] = s->buf[i-n];
}
s->bufIdx = n;
}
}
//------------------------------------------------------------------------
// MD5 message digest
//------------------------------------------------------------------------
// this works around a bug in older Sun compilers
static inline Gulong rotateLeft(Gulong x, int r) {
x &= 0xffffffff;
return ((x << r) | (x >> (32 - r))) & 0xffffffff;
}
static inline Gulong md5Round1(Gulong a, Gulong b, Gulong c, Gulong d,
Gulong Xk, Gulong s, Gulong Ti) {
return b + rotateLeft((a + ((b & c) | (~b & d)) + Xk + Ti), s);
}
static inline Gulong md5Round2(Gulong a, Gulong b, Gulong c, Gulong d,
Gulong Xk, Gulong s, Gulong Ti) {
return b + rotateLeft((a + ((b & d) | (c & ~d)) + Xk + Ti), s);
}
static inline Gulong md5Round3(Gulong a, Gulong b, Gulong c, Gulong d,
Gulong Xk, Gulong s, Gulong Ti) {
return b + rotateLeft((a + (b ^ c ^ d) + Xk + Ti), s);
}
static inline Gulong md5Round4(Gulong a, Gulong b, Gulong c, Gulong d,
Gulong Xk, Gulong s, Gulong Ti) {
return b + rotateLeft((a + (c ^ (b | ~d)) + Xk + Ti), s);
}
static void md5(Guchar *msg, int msgLen, Guchar *digest) {
Gulong x[16];
Gulong a, b, c, d, aa, bb, cc, dd;
int n64;
int i, j, k;
// compute number of 64-byte blocks
// (length + pad byte (0x80) + 8 bytes for length)
n64 = (msgLen + 1 + 8 + 63) / 64;
// initialize a, b, c, d
a = 0x67452301;
b = 0xefcdab89;
c = 0x98badcfe;
d = 0x10325476;
// loop through blocks
k = 0;
for (i = 0; i < n64; ++i) {
// grab a 64-byte block
for (j = 0; j < 16 && k < msgLen - 3; ++j, k += 4)
x[j] = (((((msg[k+3] << 8) + msg[k+2]) << 8) + msg[k+1]) << 8) + msg[k];
if (i == n64 - 1) {
if (k == msgLen - 3)
x[j] = 0x80000000 + (((msg[k+2] << 8) + msg[k+1]) << 8) + msg[k];
else if (k == msgLen - 2)
x[j] = 0x800000 + (msg[k+1] << 8) + msg[k];
else if (k == msgLen - 1)
x[j] = 0x8000 + msg[k];
else
x[j] = 0x80;
++j;
while (j < 16)
x[j++] = 0;
x[14] = msgLen << 3;
}
// save a, b, c, d
aa = a;
bb = b;
cc = c;
dd = d;
// round 1
a = md5Round1(a, b, c, d, x[0], 7, 0xd76aa478);
d = md5Round1(d, a, b, c, x[1], 12, 0xe8c7b756);
c = md5Round1(c, d, a, b, x[2], 17, 0x242070db);
b = md5Round1(b, c, d, a, x[3], 22, 0xc1bdceee);
a = md5Round1(a, b, c, d, x[4], 7, 0xf57c0faf);
d = md5Round1(d, a, b, c, x[5], 12, 0x4787c62a);
c = md5Round1(c, d, a, b, x[6], 17, 0xa8304613);
b = md5Round1(b, c, d, a, x[7], 22, 0xfd469501);
a = md5Round1(a, b, c, d, x[8], 7, 0x698098d8);
d = md5Round1(d, a, b, c, x[9], 12, 0x8b44f7af);
c = md5Round1(c, d, a, b, x[10], 17, 0xffff5bb1);
b = md5Round1(b, c, d, a, x[11], 22, 0x895cd7be);
a = md5Round1(a, b, c, d, x[12], 7, 0x6b901122);
d = md5Round1(d, a, b, c, x[13], 12, 0xfd987193);
c = md5Round1(c, d, a, b, x[14], 17, 0xa679438e);
b = md5Round1(b, c, d, a, x[15], 22, 0x49b40821);
// round 2
a = md5Round2(a, b, c, d, x[1], 5, 0xf61e2562);
d = md5Round2(d, a, b, c, x[6], 9, 0xc040b340);
c = md5Round2(c, d, a, b, x[11], 14, 0x265e5a51);
b = md5Round2(b, c, d, a, x[0], 20, 0xe9b6c7aa);
a = md5Round2(a, b, c, d, x[5], 5, 0xd62f105d);
d = md5Round2(d, a, b, c, x[10], 9, 0x02441453);
c = md5Round2(c, d, a, b, x[15], 14, 0xd8a1e681);
b = md5Round2(b, c, d, a, x[4], 20, 0xe7d3fbc8);
a = md5Round2(a, b, c, d, x[9], 5, 0x21e1cde6);
d = md5Round2(d, a, b, c, x[14], 9, 0xc33707d6);
c = md5Round2(c, d, a, b, x[3], 14, 0xf4d50d87);
b = md5Round2(b, c, d, a, x[8], 20, 0x455a14ed);
a = md5Round2(a, b, c, d, x[13], 5, 0xa9e3e905);
d = md5Round2(d, a, b, c, x[2], 9, 0xfcefa3f8);
c = md5Round2(c, d, a, b, x[7], 14, 0x676f02d9);
b = md5Round2(b, c, d, a, x[12], 20, 0x8d2a4c8a);
// round 3
a = md5Round3(a, b, c, d, x[5], 4, 0xfffa3942);
d = md5Round3(d, a, b, c, x[8], 11, 0x8771f681);
c = md5Round3(c, d, a, b, x[11], 16, 0x6d9d6122);
b = md5Round3(b, c, d, a, x[14], 23, 0xfde5380c);
a = md5Round3(a, b, c, d, x[1], 4, 0xa4beea44);
d = md5Round3(d, a, b, c, x[4], 11, 0x4bdecfa9);
c = md5Round3(c, d, a, b, x[7], 16, 0xf6bb4b60);
b = md5Round3(b, c, d, a, x[10], 23, 0xbebfbc70);
a = md5Round3(a, b, c, d, x[13], 4, 0x289b7ec6);
d = md5Round3(d, a, b, c, x[0], 11, 0xeaa127fa);
c = md5Round3(c, d, a, b, x[3], 16, 0xd4ef3085);
b = md5Round3(b, c, d, a, x[6], 23, 0x04881d05);
a = md5Round3(a, b, c, d, x[9], 4, 0xd9d4d039);
d = md5Round3(d, a, b, c, x[12], 11, 0xe6db99e5);
c = md5Round3(c, d, a, b, x[15], 16, 0x1fa27cf8);
b = md5Round3(b, c, d, a, x[2], 23, 0xc4ac5665);
// round 4
a = md5Round4(a, b, c, d, x[0], 6, 0xf4292244);
d = md5Round4(d, a, b, c, x[7], 10, 0x432aff97);
c = md5Round4(c, d, a, b, x[14], 15, 0xab9423a7);
b = md5Round4(b, c, d, a, x[5], 21, 0xfc93a039);
a = md5Round4(a, b, c, d, x[12], 6, 0x655b59c3);
d = md5Round4(d, a, b, c, x[3], 10, 0x8f0ccc92);
c = md5Round4(c, d, a, b, x[10], 15, 0xffeff47d);
b = md5Round4(b, c, d, a, x[1], 21, 0x85845dd1);
a = md5Round4(a, b, c, d, x[8], 6, 0x6fa87e4f);
d = md5Round4(d, a, b, c, x[15], 10, 0xfe2ce6e0);
c = md5Round4(c, d, a, b, x[6], 15, 0xa3014314);
b = md5Round4(b, c, d, a, x[13], 21, 0x4e0811a1);
a = md5Round4(a, b, c, d, x[4], 6, 0xf7537e82);
d = md5Round4(d, a, b, c, x[11], 10, 0xbd3af235);
c = md5Round4(c, d, a, b, x[2], 15, 0x2ad7d2bb);
b = md5Round4(b, c, d, a, x[9], 21, 0xeb86d391);
// increment a, b, c, d
a += aa;
b += bb;
c += cc;
d += dd;
}
// break digest into bytes
digest[0] = (Guchar)(a & 0xff);
digest[1] = (Guchar)((a >>= 8) & 0xff);
digest[2] = (Guchar)((a >>= 8) & 0xff);
digest[3] = (Guchar)((a >>= 8) & 0xff);
digest[4] = (Guchar)(b & 0xff);
digest[5] = (Guchar)((b >>= 8) & 0xff);
digest[6] = (Guchar)((b >>= 8) & 0xff);
digest[7] = (Guchar)((b >>= 8) & 0xff);
digest[8] = (Guchar)(c & 0xff);
digest[9] = (Guchar)((c >>= 8) & 0xff);
digest[10] = (Guchar)((c >>= 8) & 0xff);
digest[11] = (Guchar)((c >>= 8) & 0xff);
digest[12] = (Guchar)(d & 0xff);
digest[13] = (Guchar)((d >>= 8) & 0xff);
digest[14] = (Guchar)((d >>= 8) & 0xff);
digest[15] = (Guchar)((d >>= 8) & 0xff);
}