+++ /dev/null
-//========================================================================
-//
-// 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 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
-//------------------------------------------------------------------------
-
-Decrypt::Decrypt(Guchar *fileKey, int keyLength, int objNum, int objGen) {
- int i;
-
- // 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;
- md5(objKey, keyLength + 5, objKey);
-
- // set up for decryption
- x = y = 0;
- if ((objKeyLength = keyLength + 5) > 16) {
- objKeyLength = 16;
- }
- rc4InitKey(objKey, objKeyLength, state);
-}
-
-void Decrypt::reset() {
- x = y = 0;
- rc4InitKey(objKey, objKeyLength, state);
-}
-
-Guchar Decrypt::decryptByte(Guchar c) {
- return rc4DecryptByte(state, &x, &y, c);
-}
-
-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;
-}
-
-//------------------------------------------------------------------------
-// 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];
-}
-
-//------------------------------------------------------------------------
-// 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);
-}
git.asbjorn.biz / swftools.git / blobdiff