diff options
author | Tom Sepez <tsepez@chromium.org> | 2016-03-09 11:51:13 -0800 |
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committer | Tom Sepez <tsepez@chromium.org> | 2016-03-09 11:51:13 -0800 |
commit | ca78d9a5289354f85607f92f68713b25df4fb6ad (patch) | |
tree | ff5af854fe773699d9158b02723f9bf2284643ad /core/src/fpdfapi/fpdf_parser/cpdf_standard_security_handler.cpp | |
parent | 0c64d69b6ee66018eea20c6dc21f2bed6f199a2a (diff) | |
download | pdfium-ca78d9a5289354f85607f92f68713b25df4fb6ad.tar.xz |
Split off IPDF_SecurityHandler and CPDF_StandardSecurityHandler.
R=dsinclair@chromium.org
Review URL: https://codereview.chromium.org/1781593003 .
Diffstat (limited to 'core/src/fpdfapi/fpdf_parser/cpdf_standard_security_handler.cpp')
-rw-r--r-- | core/src/fpdfapi/fpdf_parser/cpdf_standard_security_handler.cpp | 709 |
1 files changed, 709 insertions, 0 deletions
diff --git a/core/src/fpdfapi/fpdf_parser/cpdf_standard_security_handler.cpp b/core/src/fpdfapi/fpdf_parser/cpdf_standard_security_handler.cpp new file mode 100644 index 0000000000..84da42ec19 --- /dev/null +++ b/core/src/fpdfapi/fpdf_parser/cpdf_standard_security_handler.cpp @@ -0,0 +1,709 @@ +// 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 "core/src/fpdfapi/fpdf_parser/cpdf_standard_security_handler.h" + +#include "core/include/fdrm/fx_crypt.h" +#include "core/include/fpdfapi/cpdf_parser.h" +#include "core/include/fpdfapi/fpdf_parser.h" + +namespace { + +const uint8_t 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, + const uint8_t* password, + FX_DWORD pass_size, + uint8_t* key, + int keylen, + FX_BOOL bIgnoreMeta, + CPDF_Array* pIdArray) { + int revision = pEncrypt->GetIntegerBy("R"); + uint8_t passcode[32]; + for (FX_DWORD i = 0; i < 32; i++) { + passcode[i] = i < pass_size ? password[i] : defpasscode[i - pass_size]; + } + uint8_t md5[100]; + CRYPT_MD5Start(md5); + CRYPT_MD5Update(md5, passcode, 32); + CFX_ByteString okey = pEncrypt->GetStringBy("O"); + CRYPT_MD5Update(md5, (uint8_t*)okey.c_str(), okey.GetLength()); + FX_DWORD perm = pEncrypt->GetIntegerBy("P"); + CRYPT_MD5Update(md5, (uint8_t*)&perm, 4); + if (pIdArray) { + CFX_ByteString id = pIdArray->GetStringAt(0); + CRYPT_MD5Update(md5, (uint8_t*)id.c_str(), id.GetLength()); + } + if (!bIgnoreMeta && revision >= 3 && + !pEncrypt->GetIntegerBy("EncryptMetadata", 1)) { + FX_DWORD tag = (FX_DWORD)-1; + CRYPT_MD5Update(md5, (uint8_t*)&tag, 4); + } + uint8_t 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_memset(key, 0, keylen); + FXSYS_memcpy(key, digest, copy_len); +} + +} // namespace + +IPDF_SecurityHandler::~IPDF_SecurityHandler() {} + +CPDF_StandardSecurityHandler::CPDF_StandardSecurityHandler() { + m_Version = 0; + m_Revision = 0; + m_pParser = NULL; + m_pEncryptDict = NULL; + m_Permissions = 0; + m_Cipher = FXCIPHER_NONE; + m_KeyLen = 0; +} + +CPDF_StandardSecurityHandler::~CPDF_StandardSecurityHandler() {} + +CPDF_CryptoHandler* CPDF_StandardSecurityHandler::CreateCryptoHandler() { + return new CPDF_StandardCryptoHandler; +} + +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(int32_t 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; + } + } + 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, + const CFX_ByteStringC& name, + int& cipher, + int& keylen) { + int Version = pEncryptDict->GetIntegerBy("V"); + cipher = FXCIPHER_RC4; + keylen = 0; + if (Version >= 4) { + CPDF_Dictionary* pCryptFilters = pEncryptDict->GetDictBy("CF"); + if (!pCryptFilters) { + return FALSE; + } + if (name == "Identity") { + cipher = FXCIPHER_NONE; + } else { + CPDF_Dictionary* pDefFilter = pCryptFilters->GetDictBy(name); + if (!pDefFilter) { + return FALSE; + } + int nKeyBits = 0; + if (Version == 4) { + nKeyBits = pDefFilter->GetIntegerBy("Length", 0); + if (nKeyBits == 0) { + nKeyBits = pEncryptDict->GetIntegerBy("Length", 128); + } + } else { + nKeyBits = pEncryptDict->GetIntegerBy("Length", 256); + } + if (nKeyBits < 40) { + nKeyBits *= 8; + } + keylen = nKeyBits / 8; + CFX_ByteString cipher_name = pDefFilter->GetStringBy("CFM"); + if (cipher_name == "AESV2" || cipher_name == "AESV3") { + cipher = FXCIPHER_AES; + } + } + } else { + keylen = Version > 1 ? pEncryptDict->GetIntegerBy("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_Version = pEncryptDict->GetIntegerBy("V"); + m_Revision = pEncryptDict->GetIntegerBy("R"); + m_Permissions = pEncryptDict->GetIntegerBy("P", -1); + if (m_Version < 4) { + return _LoadCryptInfo(pEncryptDict, CFX_ByteString(), m_Cipher, m_KeyLen); + } + CFX_ByteString stmf_name = pEncryptDict->GetStringBy("StmF"); + CFX_ByteString strf_name = pEncryptDict->GetStringBy("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_Version = pEncryptDict->GetIntegerBy("V"); + m_Revision = pEncryptDict->GetIntegerBy("R"); + m_Permissions = pEncryptDict->GetIntegerBy("P", -1); + CFX_ByteString strf_name, stmf_name; + if (m_Version >= 4) { + stmf_name = pEncryptDict->GetStringBy("StmF"); + strf_name = pEncryptDict->GetStringBy("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; +} + +FX_BOOL CPDF_StandardSecurityHandler::GetCryptInfo(int& cipher, + const uint8_t*& buffer, + int& keylen) { + cipher = m_Cipher; + buffer = m_EncryptKey; + keylen = m_KeyLen; + return TRUE; +} +#define FX_GET_32WORD(n, b, i) \ + { \ + (n) = (FX_DWORD)( \ + ((uint64_t)(b)[(i)] << 24) | ((uint64_t)(b)[(i) + 1] << 16) | \ + ((uint64_t)(b)[(i) + 2] << 8) | ((uint64_t)(b)[(i) + 3])); \ + } +int BigOrder64BitsMod3(uint8_t* data) { + uint64_t 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(const uint8_t* password, + FX_DWORD size, + const uint8_t* salt, + const uint8_t* vector, + uint8_t* hash) { + int iBlockSize = 32; + uint8_t sha[128]; + CRYPT_SHA256Start(sha); + CRYPT_SHA256Update(sha, password, size); + CRYPT_SHA256Update(sha, salt, 8); + if (vector) { + CRYPT_SHA256Update(sha, vector, 48); + } + uint8_t digest[32]; + CRYPT_SHA256Finish(sha, digest); + CFX_ByteTextBuf buf; + uint8_t* input = digest; + uint8_t* key = input; + uint8_t* iv = input + 16; + uint8_t* E = buf.GetBuffer(); + int iBufLen = buf.GetLength(); + CFX_ByteTextBuf interDigest; + int i = 0; + uint8_t* aes = FX_Alloc(uint8_t, 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_memcpy(hash, input, 32); + } +} +FX_BOOL CPDF_StandardSecurityHandler::AES256_CheckPassword( + const uint8_t* password, + FX_DWORD size, + FX_BOOL bOwner, + uint8_t* key) { + CFX_ByteString okey = + m_pEncryptDict ? m_pEncryptDict->GetStringBy("O") : CFX_ByteString(); + if (okey.GetLength() < 48) { + return FALSE; + } + CFX_ByteString ukey = + m_pEncryptDict ? m_pEncryptDict->GetStringBy("U") : CFX_ByteString(); + if (ukey.GetLength() < 48) { + return FALSE; + } + const uint8_t* pkey = bOwner ? (const uint8_t*)okey : (const uint8_t*)ukey; + uint8_t sha[128]; + uint8_t digest[32]; + if (m_Revision >= 6) { + Revision6_Hash(password, size, (const uint8_t*)pkey + 32, + (bOwner ? (const uint8_t*)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_memcmp(digest, pkey, 32) != 0) { + return FALSE; + } + if (!key) { + return TRUE; + } + if (m_Revision >= 6) { + Revision6_Hash(password, size, (const uint8_t*)pkey + 40, + (bOwner ? (const uint8_t*)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 + ? m_pEncryptDict->GetStringBy(bOwner ? "OE" : "UE") + : CFX_ByteString(); + if (ekey.GetLength() < 32) { + return FALSE; + } + uint8_t* aes = FX_Alloc(uint8_t, 2048); + CRYPT_AESSetKey(aes, 16, digest, 32, FALSE); + uint8_t iv[16]; + FXSYS_memset(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->GetStringBy("Perms"); + if (perms.IsEmpty()) { + return FALSE; + } + uint8_t perms_buf[16]; + FXSYS_memset(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_memcpy(perms_buf, (const uint8_t*)perms, copy_len); + uint8_t 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(const uint8_t* password, + FX_DWORD size, + FX_BOOL bOwner, + uint8_t* key, + int32_t key_len) { + if (m_Revision >= 5) { + return AES256_CheckPassword(password, size, bOwner, key); + } + uint8_t keybuf[32]; + if (!key) { + 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( + const uint8_t* password, + FX_DWORD pass_size, + FX_BOOL bIgnoreEncryptMeta, + uint8_t* key, + int32_t key_len) { + CalcEncryptKey(m_pEncryptDict, password, pass_size, key, key_len, + bIgnoreEncryptMeta, m_pParser->GetIDArray()); + CFX_ByteString ukey = + m_pEncryptDict ? m_pEncryptDict->GetStringBy("U") : CFX_ByteString(); + if (ukey.GetLength() < 16) { + return FALSE; + } + uint8_t ukeybuf[32]; + if (m_Revision == 2) { + FXSYS_memcpy(ukeybuf, defpasscode, 32); + CRYPT_ArcFourCryptBlock(ukeybuf, 32, key, key_len); + } else { + uint8_t test[32], tmpkey[32]; + FX_DWORD copy_len = sizeof(test); + if (copy_len > (FX_DWORD)ukey.GetLength()) { + copy_len = ukey.GetLength(); + } + FXSYS_memset(test, 0, sizeof(test)); + FXSYS_memset(tmpkey, 0, sizeof(tmpkey)); + FXSYS_memcpy(test, ukey.c_str(), 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); + } + uint8_t md5[100]; + CRYPT_MD5Start(md5); + CRYPT_MD5Update(md5, defpasscode, 32); + CPDF_Array* pIdArray = m_pParser->GetIDArray(); + if (pIdArray) { + CFX_ByteString id = pIdArray->GetStringAt(0); + CRYPT_MD5Update(md5, (uint8_t*)id.c_str(), id.GetLength()); + } + CRYPT_MD5Finish(md5, ukeybuf); + return FXSYS_memcmp(test, ukeybuf, 16) == 0; + } + if (FXSYS_memcmp((void*)ukey.c_str(), ukeybuf, 16) == 0) { + return TRUE; + } + return FALSE; +} +CFX_ByteString CPDF_StandardSecurityHandler::GetUserPassword( + const uint8_t* owner_pass, + FX_DWORD pass_size, + int32_t key_len) { + CFX_ByteString okey = m_pEncryptDict->GetStringBy("O"); + uint8_t passcode[32]; + FX_DWORD i; + for (i = 0; i < 32; i++) { + passcode[i] = i < pass_size ? owner_pass[i] : defpasscode[i - pass_size]; + } + uint8_t digest[16]; + CRYPT_MD5Generate(passcode, 32, digest); + if (m_Revision >= 3) { + for (int i = 0; i < 50; i++) { + CRYPT_MD5Generate(digest, 16, digest); + } + } + uint8_t enckey[32]; + FXSYS_memset(enckey, 0, sizeof(enckey)); + FX_DWORD copy_len = key_len; + if (copy_len > sizeof(digest)) { + copy_len = sizeof(digest); + } + FXSYS_memcpy(enckey, digest, copy_len); + int okeylen = okey.GetLength(); + if (okeylen > 32) { + okeylen = 32; + } + uint8_t okeybuf[64]; + FXSYS_memset(okeybuf, 0, sizeof(okeybuf)); + FXSYS_memcpy(okeybuf, okey.c_str(), okeylen); + if (m_Revision == 2) { + CRYPT_ArcFourCryptBlock(okeybuf, okeylen, enckey, key_len); + } else { + for (int i = 19; i >= 0; i--) { + uint8_t tempkey[32]; + FXSYS_memset(tempkey, 0, sizeof(tempkey)); + 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( + const uint8_t* password, + FX_DWORD pass_size, + uint8_t* key, + int32_t 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->GetBooleanBy("EncryptMetadata", TRUE); +} + +void CPDF_StandardSecurityHandler::OnCreate(CPDF_Dictionary* pEncryptDict, + CPDF_Array* pIdArray, + const uint8_t* user_pass, + FX_DWORD user_size, + const uint8_t* 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 || owner_size == 0)) { + owner_pass = user_pass; + owner_size = user_size; + } + if (m_Revision >= 5) { + int t = (int)time(NULL); + uint8_t sha[128]; + CRYPT_SHA256Start(sha); + CRYPT_SHA256Update(sha, (uint8_t*)&t, sizeof t); + CRYPT_SHA256Update(sha, m_EncryptKey, 32); + CRYPT_SHA256Update(sha, (uint8_t*)"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->GetBooleanBy("EncryptMetadata", TRUE), + m_EncryptKey); + } + return; + } + if (bDefault) { + uint8_t passcode[32]; + FX_DWORD i; + for (i = 0; i < 32; i++) { + passcode[i] = + i < owner_size ? owner_pass[i] : defpasscode[i - owner_size]; + } + uint8_t digest[16]; + CRYPT_MD5Generate(passcode, 32, digest); + if (m_Revision >= 3) { + for (int i = 0; i < 50; i++) { + CRYPT_MD5Generate(digest, 16, digest); + } + } + uint8_t enckey[32]; + FXSYS_memcpy(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); + uint8_t tempkey[32]; + if (m_Revision >= 3) { + for (i = 1; i <= 19; i++) { + for (int j = 0; j < key_len; j++) { + tempkey[j] = enckey[j] ^ (uint8_t)i; + } + CRYPT_ArcFourCryptBlock(passcode, 32, tempkey, key_len); + } + } + pEncryptDict->SetAtString("O", CFX_ByteString(passcode, 32)); + } + CalcEncryptKey(m_pEncryptDict, (uint8_t*)user_pass, user_size, m_EncryptKey, + key_len, FALSE, pIdArray); + if (m_Revision < 3) { + uint8_t tempbuf[32]; + FXSYS_memcpy(tempbuf, defpasscode, 32); + CRYPT_ArcFourCryptBlock(tempbuf, 32, m_EncryptKey, key_len); + pEncryptDict->SetAtString("U", CFX_ByteString(tempbuf, 32)); + } else { + uint8_t md5[100]; + CRYPT_MD5Start(md5); + CRYPT_MD5Update(md5, defpasscode, 32); + if (pIdArray) { + CFX_ByteString id = pIdArray->GetStringAt(0); + CRYPT_MD5Update(md5, (uint8_t*)id.c_str(), id.GetLength()); + } + uint8_t digest[32]; + CRYPT_MD5Finish(md5, digest); + CRYPT_ArcFourCryptBlock(digest, 16, m_EncryptKey, key_len); + uint8_t tempkey[32]; + for (int i = 1; i <= 19; i++) { + for (int j = 0; j < key_len; j++) { + tempkey[j] = m_EncryptKey[j] ^ (uint8_t)i; + } + CRYPT_ArcFourCryptBlock(digest, 16, tempkey, key_len); + } + CRYPT_MD5Generate(digest, 16, digest + 16); + pEncryptDict->SetAtString("U", CFX_ByteString(digest, 32)); + } +} +void CPDF_StandardSecurityHandler::OnCreate(CPDF_Dictionary* pEncryptDict, + CPDF_Array* pIdArray, + const uint8_t* user_pass, + FX_DWORD user_size, + const uint8_t* 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, + const uint8_t* 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, + const uint8_t* password, + FX_DWORD size, + FX_BOOL bOwner, + const uint8_t* key) { + uint8_t sha[128]; + CRYPT_SHA1Start(sha); + CRYPT_SHA1Update(sha, key, 32); + CRYPT_SHA1Update(sha, (uint8_t*)"hello", 5); + uint8_t digest[20]; + CRYPT_SHA1Finish(sha, digest); + CFX_ByteString ukey = pEncryptDict->GetStringBy("U"); + uint8_t digest1[48]; + if (m_Revision >= 6) { + Revision6_Hash(password, size, digest, + (bOwner ? (const uint8_t*)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_memcpy(digest1 + 32, digest, 16); + pEncryptDict->SetAtString(bOwner ? "O" : "U", CFX_ByteString(digest1, 48)); + if (m_Revision >= 6) { + Revision6_Hash(password, size, digest + 8, + (bOwner ? (const uint8_t*)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); + } + uint8_t* aes = FX_Alloc(uint8_t, 2048); + CRYPT_AESSetKey(aes, 16, digest1, 32, TRUE); + uint8_t iv[16]; + FXSYS_memset(iv, 0, 16); + CRYPT_AESSetIV(aes, iv); + CRYPT_AESEncrypt(aes, digest1, key, 32); + FX_Free(aes); + pEncryptDict->SetAtString(bOwner ? "OE" : "UE", CFX_ByteString(digest1, 32)); +} +void CPDF_StandardSecurityHandler::AES256_SetPerms( + CPDF_Dictionary* pEncryptDict, + FX_DWORD permissions, + FX_BOOL bEncryptMetadata, + const uint8_t* key) { + uint8_t buf[16]; + buf[0] = (uint8_t)permissions; + buf[1] = (uint8_t)(permissions >> 8); + buf[2] = (uint8_t)(permissions >> 16); + buf[3] = (uint8_t)(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'; + uint8_t* aes = FX_Alloc(uint8_t, 2048); + CRYPT_AESSetKey(aes, 16, key, 32, TRUE); + uint8_t iv[16], buf1[16]; + FXSYS_memset(iv, 0, 16); + CRYPT_AESSetIV(aes, iv); + CRYPT_AESEncrypt(aes, buf1, buf, 16); + FX_Free(aes); + pEncryptDict->SetAtString("Perms", CFX_ByteString(buf1, 16)); +} |