From 5110c4743751145c4ae1934cd1d83bc6c55bb43f Mon Sep 17 00:00:00 2001 From: John Abd-El-Malek Date: Sat, 17 May 2014 22:33:34 -0700 Subject: Initial commit. --- .../fpdfapi/fpdf_parser/fpdf_parser_encrypt.cpp | 957 +++++++++++++++++++++ 1 file changed, 957 insertions(+) create mode 100644 core/src/fpdfapi/fpdf_parser/fpdf_parser_encrypt.cpp (limited to 'core/src/fpdfapi/fpdf_parser/fpdf_parser_encrypt.cpp') diff --git a/core/src/fpdfapi/fpdf_parser/fpdf_parser_encrypt.cpp b/core/src/fpdfapi/fpdf_parser/fpdf_parser_encrypt.cpp new file mode 100644 index 0000000000..d1f1a24488 --- /dev/null +++ b/core/src/fpdfapi/fpdf_parser/fpdf_parser_encrypt.cpp @@ -0,0 +1,957 @@ +// Copyright 2014 PDFium Authors. All rights reserved. +// Use of this source code is governed by a BSD-style license that can be +// found in the LICENSE file. + +// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com + +#include +#include "../../../include/fpdfapi/fpdf_parser.h" +#include "../../../include/fdrm/fx_crypt.h" +const FX_BYTE defpasscode[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 +}; +void CalcEncryptKey(CPDF_Dictionary* pEncrypt, FX_LPCBYTE password, FX_DWORD pass_size, + FX_LPBYTE key, int keylen, FX_BOOL bIgnoreMeta, CPDF_Array* pIdArray) +{ + int revision = pEncrypt->GetInteger(FX_BSTRC("R")); + FX_BYTE passcode[32]; + for (FX_DWORD i = 0; i < 32; i ++) { + passcode[i] = i < pass_size ? password[i] : defpasscode[i - pass_size]; + } + FX_BYTE md5[100]; + CRYPT_MD5Start(md5); + CRYPT_MD5Update(md5, passcode, 32); + CFX_ByteString okey = pEncrypt->GetString(FX_BSTRC("O")); + CRYPT_MD5Update(md5, (FX_LPBYTE)(FX_LPCSTR)okey, okey.GetLength()); + FX_DWORD perm = pEncrypt->GetInteger(FX_BSTRC("P")); + CRYPT_MD5Update(md5, (FX_LPBYTE)&perm, 4); + if (pIdArray) { + CFX_ByteString id = pIdArray->GetString(0); + CRYPT_MD5Update(md5, (FX_LPBYTE)(FX_LPCSTR)id, id.GetLength()); + } + if (!bIgnoreMeta && revision >= 3 && !pEncrypt->GetInteger(FX_BSTRC("EncryptMetadata"), 1)) { + FX_DWORD tag = (FX_DWORD) - 1; + CRYPT_MD5Update(md5, (FX_LPBYTE)&tag, 4); + } + FX_BYTE digest[16]; + CRYPT_MD5Finish(md5, digest); + FX_DWORD copy_len = keylen; + if (copy_len > sizeof(digest)) { + copy_len = sizeof(digest); + } + if (revision >= 3) { + for (int i = 0; i < 50; i ++) { + CRYPT_MD5Generate(digest, copy_len, digest); + } + } + FXSYS_memset32(key, 0, keylen); + FXSYS_memcpy32(key, digest, copy_len); +} +CPDF_CryptoHandler* CPDF_StandardSecurityHandler::CreateCryptoHandler() +{ + return FX_NEW CPDF_StandardCryptoHandler; +} +typedef struct _PDF_CRYPTOITEM : public CFX_Object { + FX_INT32 m_Cipher; + FX_INT32 m_KeyLen; + FX_BOOL m_bChecked; + CPDF_StandardCryptoHandler* m_pCryptoHandler; +} PDF_CRYPTOITEM; +CPDF_StandardSecurityHandler::CPDF_StandardSecurityHandler() +{ + m_Version = 0; + m_Revision = 0; + m_pParser = NULL; + m_pEncryptDict = NULL; + m_bOwner = FALSE; + m_Permissions = 0; + m_Cipher = FXCIPHER_NONE; + m_KeyLen = 0; +} +CPDF_StandardSecurityHandler::~CPDF_StandardSecurityHandler() +{ +} +FX_BOOL CPDF_StandardSecurityHandler::OnInit(CPDF_Parser* pParser, CPDF_Dictionary* pEncryptDict) +{ + m_pParser = pParser; + if (!LoadDict(pEncryptDict)) { + return FALSE; + } + if (m_Cipher == FXCIPHER_NONE) { + return TRUE; + } + return CheckSecurity(m_KeyLen); +} +FX_BOOL CPDF_StandardSecurityHandler::CheckSecurity(FX_INT32 key_len) +{ + CFX_ByteString password = m_pParser->GetPassword(); + if (CheckPassword(password, password.GetLength(), TRUE, m_EncryptKey, key_len)) { + if (password.IsEmpty()) { + if (!CheckPassword(password, password.GetLength(), FALSE, m_EncryptKey, key_len)) { + return FALSE; + } + } + m_bOwner = TRUE; + return TRUE; + } + return CheckPassword(password, password.GetLength(), FALSE, m_EncryptKey, key_len); +} +FX_DWORD CPDF_StandardSecurityHandler::GetPermissions() +{ + return m_Permissions; +} +static FX_BOOL _LoadCryptInfo(CPDF_Dictionary* pEncryptDict, FX_BSTR name, int& cipher, int& keylen) +{ + int Version = pEncryptDict->GetInteger(FX_BSTRC("V")); + int Revision = pEncryptDict->GetInteger(FX_BSTRC("R")); + cipher = FXCIPHER_RC4; + keylen = 0; + if (Version >= 4) { + CPDF_Dictionary* pCryptFilters = pEncryptDict->GetDict(FX_BSTRC("CF")); + if (pCryptFilters == NULL) { + return FALSE; + } + if (name == FX_BSTRC("Identity")) { + cipher = FXCIPHER_NONE; + } else { + CPDF_Dictionary* pDefFilter = pCryptFilters->GetDict(name); + if (pDefFilter == NULL) { + return FALSE; + } + int nKeyBits = 0; + if (Version == 4) { + nKeyBits = pDefFilter->GetInteger(FX_BSTRC("Length"), 0); + if (nKeyBits == 0) { + nKeyBits = pEncryptDict->GetInteger(FX_BSTRC("Length"), 128); + } + } else { + nKeyBits = pEncryptDict->GetInteger(FX_BSTRC("Length"), 256); + } + if (nKeyBits < 40) { + nKeyBits *= 8; + } + keylen = nKeyBits / 8; + CFX_ByteString cipher_name = pDefFilter->GetString(FX_BSTRC("CFM")); + if (cipher_name == FX_BSTRC("AESV2") || cipher_name == FX_BSTRC("AESV3")) { + cipher = FXCIPHER_AES; + } + } + } else { + keylen = Version > 1 ? pEncryptDict->GetInteger(FX_BSTRC("Length"), 40) / 8 : 5; + } + if (keylen > 32 || keylen < 0) { + return FALSE; + } + return TRUE; +} +FX_BOOL CPDF_StandardSecurityHandler::LoadDict(CPDF_Dictionary* pEncryptDict) +{ + m_pEncryptDict = pEncryptDict; + m_bOwner = FALSE; + m_Version = pEncryptDict->GetInteger(FX_BSTRC("V")); + m_Revision = pEncryptDict->GetInteger(FX_BSTRC("R")); + m_Permissions = pEncryptDict->GetInteger(FX_BSTRC("P"), -1); + if (m_Version < 4) { + return _LoadCryptInfo(pEncryptDict, CFX_ByteString(), m_Cipher, m_KeyLen); + } + CFX_ByteString stmf_name = pEncryptDict->GetString(FX_BSTRC("StmF")); + CFX_ByteString strf_name = pEncryptDict->GetString(FX_BSTRC("StrF")); + if (stmf_name != strf_name) { + return FALSE; + } + if (!_LoadCryptInfo(pEncryptDict, strf_name, m_Cipher, m_KeyLen)) { + return FALSE; + } + return TRUE; +} +FX_BOOL CPDF_StandardSecurityHandler::LoadDict(CPDF_Dictionary* pEncryptDict, FX_DWORD type, int& cipher, int& key_len) +{ + m_pEncryptDict = pEncryptDict; + m_bOwner = FALSE; + m_Version = pEncryptDict->GetInteger(FX_BSTRC("V")); + m_Revision = pEncryptDict->GetInteger(FX_BSTRC("R")); + m_Permissions = pEncryptDict->GetInteger(FX_BSTRC("P"), -1); + CFX_ByteString strf_name, stmf_name; + if (m_Version >= 4) { + stmf_name = pEncryptDict->GetString(FX_BSTRC("StmF")); + strf_name = pEncryptDict->GetString(FX_BSTRC("StrF")); + if (stmf_name != strf_name) { + return FALSE; + } + } + if (!_LoadCryptInfo(pEncryptDict, strf_name, cipher, key_len)) { + return FALSE; + } + m_Cipher = cipher; + m_KeyLen = key_len; + return TRUE; + return TRUE; +} +FX_BOOL CPDF_StandardSecurityHandler::GetCryptInfo(int& cipher, FX_LPCBYTE& buffer, int& keylen) +{ + cipher = m_Cipher; + buffer = m_EncryptKey; + keylen = m_KeyLen; + return TRUE; +} +#define FX_GET_32WORD(n,b,i) \ + { \ + (n) = (FX_DWORD)(( (FX_UINT64) (b)[(i)] << 24 ) \ + | ( (FX_UINT64) (b)[(i) + 1] << 16 ) \ + | ( (FX_UINT64) (b)[(i) + 2] << 8 ) \ + | ( (FX_UINT64) (b)[(i) + 3] )); \ + } +int BigOrder64BitsMod3(FX_LPBYTE data) +{ + FX_UINT64 ret = 0; + for (int i = 0; i < 4; ++i) { + FX_DWORD value; + FX_GET_32WORD(value, data, 4 * i); + ret <<= 32; + ret |= value; + ret %= 3; + } + return (int)ret; +} +void Revision6_Hash(FX_LPCBYTE password, FX_DWORD size, FX_LPCBYTE salt, FX_LPCBYTE vector, FX_LPBYTE hash) +{ + int iBlockSize = 32; + FX_BYTE sha[128]; + CRYPT_SHA256Start(sha); + CRYPT_SHA256Update(sha, password, size); + CRYPT_SHA256Update(sha, salt, 8); + if (vector) { + CRYPT_SHA256Update(sha, vector, 48); + } + FX_BYTE digest[32]; + CRYPT_SHA256Finish(sha, digest); + CFX_ByteTextBuf buf; + FX_LPBYTE input = digest; + FX_LPBYTE key = input; + FX_LPBYTE iv = input + 16; + FX_LPBYTE E = buf.GetBuffer(); + int iBufLen = buf.GetLength(); + CFX_ByteTextBuf interDigest; + int i = 0; + FX_LPBYTE aes = FX_Alloc(FX_BYTE, 2048); + while (i < 64 || i < E[iBufLen - 1] + 32) { + int iRoundSize = size + iBlockSize; + if (vector) { + iRoundSize += 48; + } + iBufLen = iRoundSize * 64; + buf.EstimateSize(iBufLen); + E = buf.GetBuffer(); + CFX_ByteTextBuf content; + for (int j = 0; j < 64; ++j) { + content.AppendBlock(password, size); + content.AppendBlock(input, iBlockSize); + if (vector) { + content.AppendBlock(vector, 48); + } + } + CRYPT_AESSetKey(aes, 16, key, 16, TRUE); + CRYPT_AESSetIV(aes, iv); + CRYPT_AESEncrypt(aes, E, content.GetBuffer(), iBufLen); + int iHash = 0; + switch (BigOrder64BitsMod3(E)) { + case 0: + iHash = 0; + iBlockSize = 32; + break; + case 1: + iHash = 1; + iBlockSize = 48; + break; + default: + iHash = 2; + iBlockSize = 64; + break; + } + interDigest.EstimateSize(iBlockSize); + input = interDigest.GetBuffer(); + if (iHash == 0) { + CRYPT_SHA256Generate(E, iBufLen, input); + } else if (iHash == 1) { + CRYPT_SHA384Generate(E, iBufLen, input); + } else if (iHash == 2) { + CRYPT_SHA512Generate(E, iBufLen, input); + } + key = input; + iv = input + 16; + ++i; + } + FX_Free(aes); + if (hash) { + FXSYS_memcpy32(hash, input, 32); + } +} +FX_BOOL CPDF_StandardSecurityHandler::AES256_CheckPassword(FX_LPCBYTE password, FX_DWORD size, + FX_BOOL bOwner, FX_LPBYTE key) +{ + CFX_ByteString okey = m_pEncryptDict->GetString(FX_BSTRC("O")); + if (okey.GetLength() < 48) { + return FALSE; + } + CFX_ByteString ukey = m_pEncryptDict->GetString(FX_BSTRC("U")); + if (ukey.GetLength() < 48) { + return FALSE; + } + FX_LPCBYTE pkey = bOwner ? (FX_LPCBYTE)okey : (FX_LPCBYTE)ukey; + FX_BYTE sha[128]; + FX_BYTE digest[32]; + if (m_Revision >= 6) { + Revision6_Hash(password, size, (FX_LPCBYTE)pkey + 32, (bOwner ? (FX_LPCBYTE)ukey : NULL), digest); + } else { + CRYPT_SHA256Start(sha); + CRYPT_SHA256Update(sha, password, size); + CRYPT_SHA256Update(sha, pkey + 32, 8); + if (bOwner) { + CRYPT_SHA256Update(sha, ukey, 48); + } + CRYPT_SHA256Finish(sha, digest); + } + if (FXSYS_memcmp32(digest, pkey, 32) != 0) { + return FALSE; + } + if (key == NULL) { + return TRUE; + } + if (m_Revision >= 6) { + Revision6_Hash(password, size, (FX_LPCBYTE)pkey + 40, (bOwner ? (FX_LPCBYTE)ukey : NULL), digest); + } else { + CRYPT_SHA256Start(sha); + CRYPT_SHA256Update(sha, password, size); + CRYPT_SHA256Update(sha, pkey + 40, 8); + if (bOwner) { + CRYPT_SHA256Update(sha, ukey, 48); + } + CRYPT_SHA256Finish(sha, digest); + } + CFX_ByteString ekey = m_pEncryptDict->GetString(bOwner ? FX_BSTRC("OE") : FX_BSTRC("UE")); + if (ekey.GetLength() < 32) { + return FALSE; + } + FX_BYTE* aes = FX_Alloc(FX_BYTE, 2048); + CRYPT_AESSetKey(aes, 16, digest, 32, FALSE); + FX_BYTE iv[16]; + FXSYS_memset32(iv, 0, 16); + CRYPT_AESSetIV(aes, iv); + CRYPT_AESDecrypt(aes, key, ekey, 32); + CRYPT_AESSetKey(aes, 16, key, 32, FALSE); + CRYPT_AESSetIV(aes, iv); + CFX_ByteString perms = m_pEncryptDict->GetString(FX_BSTRC("Perms")); + if (perms.IsEmpty()) { + return FALSE; + } + FX_BYTE perms_buf[16]; + FXSYS_memset32(perms_buf, 0, sizeof(perms_buf)); + FX_DWORD copy_len = sizeof(perms_buf); + if (copy_len > (FX_DWORD)perms.GetLength()) { + copy_len = perms.GetLength(); + } + FXSYS_memcpy32(perms_buf, (FX_LPCBYTE)perms, copy_len); + FX_BYTE buf[16]; + CRYPT_AESDecrypt(aes, buf, perms_buf, 16); + FX_Free(aes); + if (buf[9] != 'a' || buf[10] != 'd' || buf[11] != 'b') { + return FALSE; + } + if (FXDWORD_GET_LSBFIRST(buf) != m_Permissions) { + return FALSE; + } + if ((buf[8] == 'T' && !IsMetadataEncrypted()) || (buf[8] == 'F' && IsMetadataEncrypted())) { + return FALSE; + } + return TRUE; +} +int CPDF_StandardSecurityHandler::CheckPassword(FX_LPCBYTE password, FX_DWORD pass_size, FX_BOOL bOwner, FX_LPBYTE key) +{ + return CheckPassword(password, pass_size, bOwner, key, m_KeyLen); +} +int CPDF_StandardSecurityHandler::CheckPassword(FX_LPCBYTE password, FX_DWORD size, FX_BOOL bOwner, FX_LPBYTE key, FX_INT32 key_len) +{ + if (m_Revision >= 5) { + return AES256_CheckPassword(password, size, bOwner, key); + } + FX_BYTE keybuf[32]; + if (key == NULL) { + key = keybuf; + } + if (bOwner) { + return CheckOwnerPassword(password, size, key, key_len); + } + return CheckUserPassword(password, size, FALSE, key, key_len) || CheckUserPassword(password, size, TRUE, key, key_len); +} +FX_BOOL CPDF_StandardSecurityHandler::CheckUserPassword(FX_LPCBYTE password, FX_DWORD pass_size, + FX_BOOL bIgnoreEncryptMeta, FX_LPBYTE key, FX_INT32 key_len) +{ + CalcEncryptKey(m_pEncryptDict, password, pass_size, key, key_len, bIgnoreEncryptMeta, + m_pParser->GetIDArray()); + CFX_ByteString ukey = m_pEncryptDict->GetString(FX_BSTRC("U")); + if (ukey.GetLength() < 16) { + return FALSE; + } + FX_BYTE ukeybuf[32]; + if (m_Revision == 2) { + FXSYS_memcpy32(ukeybuf, defpasscode, 32); + CRYPT_ArcFourCryptBlock(ukeybuf, 32, key, key_len); + } else { + FX_BYTE test[32], tmpkey[32]; + FX_DWORD copy_len = sizeof(test); + if (copy_len > (FX_DWORD)ukey.GetLength()) { + copy_len = ukey.GetLength(); + } + FXSYS_memset32(test, 0, sizeof(test)); + FXSYS_memcpy32(test, (FX_LPCSTR)ukey, copy_len); + for (int i = 19; i >= 0; i --) { + for (int j = 0; j < key_len; j ++) { + tmpkey[j] = key[j] ^ i; + } + CRYPT_ArcFourCryptBlock(test, 32, tmpkey, key_len); + } + FX_BYTE md5[100]; + CRYPT_MD5Start(md5); + CRYPT_MD5Update(md5, defpasscode, 32); + CPDF_Array* pIdArray = m_pParser->GetIDArray(); + if (pIdArray) { + CFX_ByteString id = pIdArray->GetString(0); + CRYPT_MD5Update(md5, (FX_LPBYTE)(FX_LPCSTR)id, id.GetLength()); + } + CRYPT_MD5Finish(md5, ukeybuf); + return FXSYS_memcmp32(test, ukeybuf, 16) == 0; + } + if (FXSYS_memcmp32((FX_LPVOID)(FX_LPCSTR)ukey, ukeybuf, 16) == 0) { + return TRUE; + } + return FALSE; +} +CFX_ByteString CPDF_StandardSecurityHandler::GetUserPassword(FX_LPCBYTE owner_pass, FX_DWORD pass_size) +{ + return GetUserPassword(owner_pass, pass_size, m_KeyLen); +} +CFX_ByteString CPDF_StandardSecurityHandler::GetUserPassword(FX_LPCBYTE owner_pass, FX_DWORD pass_size, FX_INT32 key_len) +{ + CFX_ByteString okey = m_pEncryptDict->GetString(FX_BSTRC("O")); + FX_BYTE passcode[32]; + FX_DWORD i; + for (i = 0; i < 32; i ++) { + passcode[i] = i < pass_size ? owner_pass[i] : defpasscode[i - pass_size]; + } + FX_BYTE digest[16]; + CRYPT_MD5Generate(passcode, 32, digest); + if (m_Revision >= 3) { + for (int i = 0; i < 50; i ++) { + CRYPT_MD5Generate(digest, 16, digest); + } + } + FX_BYTE enckey[32]; + FXSYS_memset32(enckey, 0, sizeof(enckey)); + FX_DWORD copy_len = key_len; + if (copy_len > sizeof(digest)) { + copy_len = sizeof(digest); + } + FXSYS_memcpy32(enckey, digest, copy_len); + int okeylen = okey.GetLength(); + if (okeylen > 32) { + okeylen = 32; + } + FX_BYTE okeybuf[64]; + FXSYS_memcpy32(okeybuf, (FX_LPCSTR)okey, okeylen); + if (m_Revision == 2) { + CRYPT_ArcFourCryptBlock(okeybuf, okeylen, enckey, key_len); + } else { + for (int i = 19; i >= 0; i --) { + FX_BYTE tempkey[32]; + for (int j = 0; j < m_KeyLen; j ++) { + tempkey[j] = enckey[j] ^ i; + } + CRYPT_ArcFourCryptBlock(okeybuf, okeylen, tempkey, key_len); + } + } + int len = 32; + while (len && defpasscode[len - 1] == okeybuf[len - 1]) { + len --; + } + return CFX_ByteString(okeybuf, len); +} +FX_BOOL CPDF_StandardSecurityHandler::CheckOwnerPassword(FX_LPCBYTE password, FX_DWORD pass_size, + FX_LPBYTE key, FX_INT32 key_len) +{ + CFX_ByteString user_pass = GetUserPassword(password, pass_size, key_len); + if (CheckUserPassword(user_pass, user_pass.GetLength(), FALSE, key, key_len)) { + return TRUE; + } + return CheckUserPassword(user_pass, user_pass.GetLength(), TRUE, key, key_len); +} +FX_BOOL CPDF_StandardSecurityHandler::IsMetadataEncrypted() +{ + return m_pEncryptDict->GetBoolean(FX_BSTRC("EncryptMetadata"), TRUE); +} +CPDF_SecurityHandler* FPDF_CreateStandardSecurityHandler() +{ + return FX_NEW CPDF_StandardSecurityHandler; +} +void CPDF_StandardSecurityHandler::OnCreate(CPDF_Dictionary* pEncryptDict, CPDF_Array* pIdArray, + FX_LPCBYTE user_pass, FX_DWORD user_size, + FX_LPCBYTE owner_pass, FX_DWORD owner_size, FX_BOOL bDefault, FX_DWORD type) +{ + int cipher = 0, key_len = 0; + if (!LoadDict(pEncryptDict, type, cipher, key_len)) { + return; + } + if (bDefault && (owner_pass == NULL || owner_size == 0)) { + owner_pass = user_pass; + owner_size = user_size; + } + if (m_Revision >= 5) { + int t = (int)time(NULL); + FX_BYTE sha[128]; + CRYPT_SHA256Start(sha); + CRYPT_SHA256Update(sha, (FX_BYTE*)&t, sizeof t); + CRYPT_SHA256Update(sha, m_EncryptKey, 32); + CRYPT_SHA256Update(sha, (FX_BYTE*)"there", 5); + CRYPT_SHA256Finish(sha, m_EncryptKey); + AES256_SetPassword(pEncryptDict, user_pass, user_size, FALSE, m_EncryptKey); + if (bDefault) { + AES256_SetPassword(pEncryptDict, owner_pass, owner_size, TRUE, m_EncryptKey); + AES256_SetPerms(pEncryptDict, m_Permissions, pEncryptDict->GetBoolean(FX_BSTRC("EncryptMetadata"), TRUE), m_EncryptKey); + } + return; + } + if (bDefault) { + FX_BYTE passcode[32]; + FX_DWORD i; + for (i = 0; i < 32; i ++) { + passcode[i] = i < owner_size ? owner_pass[i] : defpasscode[i - owner_size]; + } + FX_BYTE digest[16]; + CRYPT_MD5Generate(passcode, 32, digest); + if (m_Revision >= 3) { + for (int i = 0; i < 50; i ++) { + CRYPT_MD5Generate(digest, 16, digest); + } + } + FX_BYTE enckey[32]; + FXSYS_memcpy32(enckey, digest, key_len); + for (i = 0; i < 32; i ++) { + passcode[i] = i < user_size ? user_pass[i] : defpasscode[i - user_size]; + } + CRYPT_ArcFourCryptBlock(passcode, 32, enckey, key_len); + FX_BYTE tempkey[32]; + if (m_Revision >= 3) { + for (i = 1; i <= 19; i ++) { + for (int j = 0; j < key_len; j ++) { + tempkey[j] = enckey[j] ^ (FX_BYTE)i; + } + CRYPT_ArcFourCryptBlock(passcode, 32, tempkey, key_len); + } + } + pEncryptDict->SetAtString(FX_BSTRC("O"), CFX_ByteString(passcode, 32)); + } + CalcEncryptKey(m_pEncryptDict, (FX_LPBYTE)user_pass, user_size, m_EncryptKey, key_len, FALSE, pIdArray); + if (m_Revision < 3) { + FX_BYTE tempbuf[32]; + FXSYS_memcpy32(tempbuf, defpasscode, 32); + CRYPT_ArcFourCryptBlock(tempbuf, 32, m_EncryptKey, key_len); + pEncryptDict->SetAtString(FX_BSTRC("U"), CFX_ByteString(tempbuf, 32)); + } else { + FX_BYTE md5[100]; + CRYPT_MD5Start(md5); + CRYPT_MD5Update(md5, defpasscode, 32); + if (pIdArray) { + CFX_ByteString id = pIdArray->GetString(0); + CRYPT_MD5Update(md5, (FX_LPBYTE)(FX_LPCSTR)id, id.GetLength()); + } + FX_BYTE digest[32]; + CRYPT_MD5Finish(md5, digest); + CRYPT_ArcFourCryptBlock(digest, 16, m_EncryptKey, key_len); + FX_BYTE tempkey[32]; + for (int i = 1; i <= 19; i ++) { + for (int j = 0; j < key_len; j ++) { + tempkey[j] = m_EncryptKey[j] ^ (FX_BYTE)i; + } + CRYPT_ArcFourCryptBlock(digest, 16, tempkey, key_len); + } + CRYPT_MD5Generate(digest, 16, digest + 16); + pEncryptDict->SetAtString(FX_BSTRC("U"), CFX_ByteString(digest, 32)); + } +} +void CPDF_StandardSecurityHandler::OnCreate(CPDF_Dictionary* pEncryptDict, CPDF_Array* pIdArray, + FX_LPCBYTE user_pass, FX_DWORD user_size, + FX_LPCBYTE owner_pass, FX_DWORD owner_size, FX_DWORD type) +{ + OnCreate(pEncryptDict, pIdArray, user_pass, user_size, owner_pass, owner_size, TRUE, type); +} +void CPDF_StandardSecurityHandler::OnCreate(CPDF_Dictionary* pEncryptDict, CPDF_Array* pIdArray, FX_LPCBYTE user_pass, FX_DWORD user_size, FX_DWORD type) +{ + OnCreate(pEncryptDict, pIdArray, user_pass, user_size, NULL, 0, FALSE, type); +} +void CPDF_StandardSecurityHandler::AES256_SetPassword(CPDF_Dictionary* pEncryptDict, FX_LPCBYTE password, FX_DWORD size, FX_BOOL bOwner, FX_LPCBYTE key) +{ + FX_BYTE sha[128]; + CRYPT_SHA1Start(sha); + CRYPT_SHA1Update(sha, key, 32); + CRYPT_SHA1Update(sha, (FX_BYTE*)"hello", 5); + FX_BYTE digest[20]; + CRYPT_SHA1Finish(sha, digest); + CFX_ByteString ukey = pEncryptDict->GetString(FX_BSTRC("U")); + FX_BYTE digest1[48]; + if (m_Revision >= 6) { + Revision6_Hash(password, size, digest, (bOwner ? (FX_LPCBYTE)ukey : NULL), digest1); + } else { + CRYPT_SHA256Start(sha); + CRYPT_SHA256Update(sha, password, size); + CRYPT_SHA256Update(sha, digest, 8); + if (bOwner) { + CRYPT_SHA256Update(sha, ukey, ukey.GetLength()); + } + CRYPT_SHA256Finish(sha, digest1); + } + FXSYS_memcpy32(digest1 + 32, digest, 16); + pEncryptDict->SetAtString(bOwner ? FX_BSTRC("O") : FX_BSTRC("U"), CFX_ByteString(digest1, 48)); + if (m_Revision >= 6) { + Revision6_Hash(password, size, digest + 8, (bOwner ? (FX_LPCBYTE)ukey : NULL), digest1); + } else { + CRYPT_SHA256Start(sha); + CRYPT_SHA256Update(sha, password, size); + CRYPT_SHA256Update(sha, digest + 8, 8); + if (bOwner) { + CRYPT_SHA256Update(sha, ukey, ukey.GetLength()); + } + CRYPT_SHA256Finish(sha, digest1); + } + FX_BYTE* aes = FX_Alloc(FX_BYTE, 2048); + CRYPT_AESSetKey(aes, 16, digest1, 32, TRUE); + FX_BYTE iv[16]; + FXSYS_memset32(iv, 0, 16); + CRYPT_AESSetIV(aes, iv); + CRYPT_AESEncrypt(aes, digest1, key, 32); + FX_Free(aes); + pEncryptDict->SetAtString(bOwner ? FX_BSTRC("OE") : FX_BSTRC("UE"), CFX_ByteString(digest1, 32)); +} +void CPDF_StandardSecurityHandler::AES256_SetPerms(CPDF_Dictionary* pEncryptDict, FX_DWORD permissions, + FX_BOOL bEncryptMetadata, FX_LPCBYTE key) +{ + FX_BYTE buf[16]; + buf[0] = (FX_BYTE)permissions; + buf[1] = (FX_BYTE)(permissions >> 8); + buf[2] = (FX_BYTE)(permissions >> 16); + buf[3] = (FX_BYTE)(permissions >> 24); + buf[4] = 0xff; + buf[5] = 0xff; + buf[6] = 0xff; + buf[7] = 0xff; + buf[8] = bEncryptMetadata ? 'T' : 'F'; + buf[9] = 'a'; + buf[10] = 'd'; + buf[11] = 'b'; + FX_BYTE* aes = FX_Alloc(FX_BYTE, 2048); + CRYPT_AESSetKey(aes, 16, key, 32, TRUE); + FX_BYTE iv[16], buf1[16]; + FXSYS_memset32(iv, 0, 16); + CRYPT_AESSetIV(aes, iv); + CRYPT_AESEncrypt(aes, buf1, buf, 16); + FX_Free(aes); + pEncryptDict->SetAtString(FX_BSTRC("Perms"), CFX_ByteString(buf1, 16)); +} +void CPDF_StandardCryptoHandler::CryptBlock(FX_BOOL bEncrypt, FX_DWORD objnum, FX_DWORD gennum, FX_LPCBYTE src_buf, FX_DWORD src_size, + FX_LPBYTE dest_buf, FX_DWORD& dest_size) +{ + if (m_Cipher == FXCIPHER_NONE) { + FXSYS_memcpy32(dest_buf, src_buf, src_size); + return; + } + FX_BYTE realkey[16]; + int realkeylen = 16; + if (m_Cipher != FXCIPHER_AES || m_KeyLen != 32) { + FX_BYTE key1[32]; + FXSYS_memcpy32(key1, m_EncryptKey, m_KeyLen); + key1[m_KeyLen + 0] = (FX_BYTE)objnum; + key1[m_KeyLen + 1] = (FX_BYTE)(objnum >> 8); + key1[m_KeyLen + 2] = (FX_BYTE)(objnum >> 16); + key1[m_KeyLen + 3] = (FX_BYTE)gennum; + key1[m_KeyLen + 4] = (FX_BYTE)(gennum >> 8); + FXSYS_memcpy32(key1 + m_KeyLen, &objnum, 3); + FXSYS_memcpy32(key1 + m_KeyLen + 3, &gennum, 2); + if (m_Cipher == FXCIPHER_AES) { + FXSYS_memcpy32(key1 + m_KeyLen + 5, "sAlT", 4); + } + CRYPT_MD5Generate(key1, m_Cipher == FXCIPHER_AES ? m_KeyLen + 9 : m_KeyLen + 5, realkey); + realkeylen = m_KeyLen + 5; + if (realkeylen > 16) { + realkeylen = 16; + } + } + if (m_Cipher == FXCIPHER_AES) { + CRYPT_AESSetKey(m_pAESContext, 16, m_KeyLen == 32 ? m_EncryptKey : realkey, m_KeyLen, bEncrypt); + if (bEncrypt) { + FX_BYTE iv[16]; + for (int i = 0; i < 16; i ++) { + iv[i] = (FX_BYTE)rand(); + } + CRYPT_AESSetIV(m_pAESContext, iv); + FXSYS_memcpy32(dest_buf, iv, 16); + int nblocks = src_size / 16; + CRYPT_AESEncrypt(m_pAESContext, dest_buf + 16, src_buf, nblocks * 16); + FX_BYTE padding[16]; + FXSYS_memcpy32(padding, src_buf + nblocks * 16, src_size % 16); + FXSYS_memset8(padding + src_size % 16, 16 - src_size % 16, 16 - src_size % 16); + CRYPT_AESEncrypt(m_pAESContext, dest_buf + nblocks * 16 + 16, padding, 16); + dest_size = 32 + nblocks * 16; + } else { + CRYPT_AESSetIV(m_pAESContext, src_buf); + CRYPT_AESDecrypt(m_pAESContext, dest_buf, src_buf + 16, src_size - 16); + dest_size = src_size - 16; + dest_size -= dest_buf[dest_size - 1]; + } + } else { + ASSERT(dest_size == src_size); + if (dest_buf != src_buf) { + FXSYS_memcpy32(dest_buf, src_buf, src_size); + } + CRYPT_ArcFourCryptBlock(dest_buf, dest_size, realkey, realkeylen); + } +} +typedef struct _AESCryptContext { + FX_BYTE m_Context[2048]; + FX_BOOL m_bIV; + FX_BYTE m_Block[16]; + FX_DWORD m_BlockOffset; +} AESCryptContext; +FX_LPVOID CPDF_StandardCryptoHandler::CryptStart(FX_DWORD objnum, FX_DWORD gennum, FX_BOOL bEncrypt) +{ + if (m_Cipher == FXCIPHER_NONE) { + return this; + } + if (m_Cipher == FXCIPHER_AES && m_KeyLen == 32) { + AESCryptContext* pContext = FX_Alloc(AESCryptContext, 1); + pContext->m_bIV = TRUE; + pContext->m_BlockOffset = 0; + CRYPT_AESSetKey(pContext->m_Context, 16, m_EncryptKey, 32, bEncrypt); + if (bEncrypt) { + for (int i = 0; i < 16; i ++) { + pContext->m_Block[i] = (FX_BYTE)rand(); + } + CRYPT_AESSetIV(pContext->m_Context, pContext->m_Block); + } + return pContext; + } + FX_BYTE key1[48]; + FXSYS_memcpy32(key1, m_EncryptKey, m_KeyLen); + FXSYS_memcpy32(key1 + m_KeyLen, &objnum, 3); + FXSYS_memcpy32(key1 + m_KeyLen + 3, &gennum, 2); + if (m_Cipher == FXCIPHER_AES) { + FXSYS_memcpy32(key1 + m_KeyLen + 5, "sAlT", 4); + } + FX_BYTE realkey[16]; + CRYPT_MD5Generate(key1, m_Cipher == FXCIPHER_AES ? m_KeyLen + 9 : m_KeyLen + 5, realkey); + int realkeylen = m_KeyLen + 5; + if (realkeylen > 16) { + realkeylen = 16; + } + if (m_Cipher == FXCIPHER_AES) { + AESCryptContext* pContext = FX_Alloc(AESCryptContext, 1); + pContext->m_bIV = TRUE; + pContext->m_BlockOffset = 0; + CRYPT_AESSetKey(pContext->m_Context, 16, realkey, 16, bEncrypt); + if (bEncrypt) { + for (int i = 0; i < 16; i ++) { + pContext->m_Block[i] = (FX_BYTE)rand(); + } + CRYPT_AESSetIV(pContext->m_Context, pContext->m_Block); + } + return pContext; + } + void* pContext = FX_Alloc(FX_BYTE, 1040); + CRYPT_ArcFourSetup(pContext, realkey, realkeylen); + return pContext; +} +FX_BOOL CPDF_StandardCryptoHandler::CryptStream(FX_LPVOID context, FX_LPCBYTE src_buf, FX_DWORD src_size, CFX_BinaryBuf& dest_buf, FX_BOOL bEncrypt) +{ + if (!context) { + return FALSE; + } + if (m_Cipher == FXCIPHER_NONE) { + dest_buf.AppendBlock(src_buf, src_size); + return TRUE; + } + if (m_Cipher == FXCIPHER_RC4) { + int old_size = dest_buf.GetSize(); + dest_buf.AppendBlock(src_buf, src_size); + CRYPT_ArcFourCrypt(context, dest_buf.GetBuffer() + old_size, src_size); + return TRUE; + } + AESCryptContext* pContext = (AESCryptContext*)context; + if (pContext->m_bIV && bEncrypt) { + dest_buf.AppendBlock(pContext->m_Block, 16); + pContext->m_bIV = FALSE; + } + FX_DWORD src_off = 0; + FX_DWORD src_left = src_size; + while (1) { + FX_DWORD copy_size = 16 - pContext->m_BlockOffset; + if (copy_size > src_left) { + copy_size = src_left; + } + FXSYS_memcpy32(pContext->m_Block + pContext->m_BlockOffset, src_buf + src_off, copy_size); + src_off += copy_size; + src_left -= copy_size; + pContext->m_BlockOffset += copy_size; + if (pContext->m_BlockOffset == 16) { + if (!bEncrypt && pContext->m_bIV) { + CRYPT_AESSetIV(pContext->m_Context, pContext->m_Block); + pContext->m_bIV = FALSE; + pContext->m_BlockOffset = 0; + } else if (src_off < src_size) { + FX_BYTE block_buf[16]; + if (bEncrypt) { + CRYPT_AESEncrypt(pContext->m_Context, block_buf, pContext->m_Block, 16); + } else { + CRYPT_AESDecrypt(pContext->m_Context, block_buf, pContext->m_Block, 16); + } + dest_buf.AppendBlock(block_buf, 16); + pContext->m_BlockOffset = 0; + } + } + if (!src_left) { + break; + } + } + return TRUE; +} +FX_BOOL CPDF_StandardCryptoHandler::CryptFinish(FX_LPVOID context, CFX_BinaryBuf& dest_buf, FX_BOOL bEncrypt) +{ + if (!context) { + return FALSE; + } + if (m_Cipher == FXCIPHER_NONE) { + return TRUE; + } + if (m_Cipher == FXCIPHER_RC4) { + FX_Free(context); + return TRUE; + } + AESCryptContext* pContext = (AESCryptContext*)context; + if (bEncrypt) { + FX_BYTE block_buf[16]; + if (pContext->m_BlockOffset == 16) { + CRYPT_AESEncrypt(pContext->m_Context, block_buf, pContext->m_Block, 16); + dest_buf.AppendBlock(block_buf, 16); + pContext->m_BlockOffset = 0; + } + FXSYS_memset8(pContext->m_Block + pContext->m_BlockOffset, (FX_BYTE)(16 - pContext->m_BlockOffset), 16 - pContext->m_BlockOffset); + CRYPT_AESEncrypt(pContext->m_Context, block_buf, pContext->m_Block, 16); + dest_buf.AppendBlock(block_buf, 16); + } else if (pContext->m_BlockOffset == 16) { + FX_BYTE block_buf[16]; + CRYPT_AESDecrypt(pContext->m_Context, block_buf, pContext->m_Block, 16); + if (block_buf[15] <= 16) { + dest_buf.AppendBlock(block_buf, 16 - block_buf[15]); + } + } + FX_Free(pContext); + return TRUE; +} +FX_LPVOID CPDF_StandardCryptoHandler::DecryptStart(FX_DWORD objnum, FX_DWORD gennum) +{ + return CryptStart(objnum, gennum, FALSE); +} +FX_DWORD CPDF_StandardCryptoHandler::DecryptGetSize(FX_DWORD src_size) +{ + return m_Cipher == FXCIPHER_AES ? src_size - 16 : src_size; +} +FX_BOOL CPDF_StandardCryptoHandler::Init(CPDF_Dictionary* pEncryptDict, CPDF_SecurityHandler* pSecurityHandler) +{ + FX_LPCBYTE key; + if (!pSecurityHandler->GetCryptInfo(m_Cipher, key, m_KeyLen)) { + return FALSE; + } + if (m_KeyLen > 32 || m_KeyLen < 0) { + return FALSE; + } + if (m_Cipher != FXCIPHER_NONE) { + FXSYS_memcpy32(m_EncryptKey, key, m_KeyLen); + } + if (m_Cipher == FXCIPHER_AES) { + m_pAESContext = FX_Alloc(FX_BYTE, 2048); + } + return TRUE; +} +FX_BOOL CPDF_StandardCryptoHandler::Init(int cipher, FX_LPCBYTE key, int keylen) +{ + if (cipher == FXCIPHER_AES) { + switch(keylen) { + case 16: + case 24: + case 32: + break; + default: + return FALSE; + } + } else if (cipher == FXCIPHER_AES2) { + if (keylen != 32) { + return FALSE; + } + } else if (cipher == FXCIPHER_RC4) { + if (keylen < 5 || keylen > 16) { + return FALSE; + } + } else { + if (keylen > 32) { + keylen = 32; + } + } + m_Cipher = cipher; + m_KeyLen = keylen; + FXSYS_memcpy32(m_EncryptKey, key, keylen); + if (m_Cipher == FXCIPHER_AES) { + m_pAESContext = FX_Alloc(FX_BYTE, 2048); + } + return TRUE; +} +FX_BOOL CPDF_StandardCryptoHandler::DecryptStream(FX_LPVOID context, FX_LPCBYTE src_buf, FX_DWORD src_size, + CFX_BinaryBuf& dest_buf) +{ + return CryptStream(context, src_buf, src_size, dest_buf, FALSE); +} +FX_BOOL CPDF_StandardCryptoHandler::DecryptFinish(FX_LPVOID context, CFX_BinaryBuf& dest_buf) +{ + return CryptFinish(context, dest_buf, FALSE); +} +FX_DWORD CPDF_StandardCryptoHandler::EncryptGetSize(FX_DWORD objnum, FX_DWORD version, FX_LPCBYTE src_buf, FX_DWORD src_size) +{ + if (m_Cipher == FXCIPHER_AES) { + return src_size + 32; + } + return src_size; +} +FX_BOOL CPDF_StandardCryptoHandler::EncryptContent(FX_DWORD objnum, FX_DWORD gennum, FX_LPCBYTE src_buf, FX_DWORD src_size, + FX_LPBYTE dest_buf, FX_DWORD& dest_size) +{ + CryptBlock(TRUE, objnum, gennum, src_buf, src_size, dest_buf, dest_size); + return TRUE; +} +void CPDF_CryptoHandler::Decrypt(FX_DWORD objnum, FX_DWORD gennum, CFX_ByteString& str) +{ + CFX_BinaryBuf dest_buf; + FX_LPVOID context = DecryptStart(objnum, gennum); + DecryptStream(context, (FX_LPCBYTE)str, str.GetLength(), dest_buf); + DecryptFinish(context, dest_buf); + str = dest_buf; +} +CPDF_StandardCryptoHandler::CPDF_StandardCryptoHandler() +{ + m_pAESContext = NULL; + m_Cipher = FXCIPHER_NONE; + m_KeyLen = 0; +} +CPDF_StandardCryptoHandler::~CPDF_StandardCryptoHandler() +{ + if (m_pAESContext) { + FX_Free(m_pAESContext); + } +} -- cgit v1.2.3