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->GetString(FX_BSTRC("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->GetString(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;
}
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->GetInteger(FX_BSTRC("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->GetString(FX_BSTRC("O"));
CRYPT_MD5Update(md5, (uint8_t*)okey.c_str(), okey.GetLength());
FX_DWORD perm = pEncrypt->GetInteger(FX_BSTRC("P"));
CRYPT_MD5Update(md5, (uint8_t*)&perm, 4);
if (pIdArray) {
CFX_ByteString id = pIdArray->GetString(0);
CRYPT_MD5Update(md5, (uint8_t*)id.c_str(), id.GetLength());
}
if (!bIgnoreMeta && revision >= 3 &&
!pEncrypt->GetInteger(FX_BSTRC("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);
}
void CPDF_SecurityHandler::OnCreate(CPDF_Dictionary* pEncryptDict,
CPDF_Array* pIdArray,
const uint8_t* user_pass,
uint32_t user_size,
const uint8_t* owner_pass,
uint32_t owner_size,
FX_BOOL bDefault,
uint32_t 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(nullptr);
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];
for (uint32_t 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 (uint32_t i = 0; i < 50; i++)
CRYPT_MD5Generate(digest, 16, digest);
}
uint8_t enckey[32];
FXSYS_memcpy(enckey, digest, key_len);
for (uint32_t 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 (uint8_t i = 1; i <= 19; i++) {
for (int j = 0; j < key_len; j++)
tempkey[j] = enckey[j] ^ 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 (uint8_t i = 1; i <= 19; i++) {
for (int j = 0; j < key_len; j++) {
tempkey[j] = m_EncryptKey[j] ^ 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,
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));
}
}