Simplify CPDF_SecurityHandler code.
- Remove parameters that always pass the same member variables.
- Use curly brace initialization instead of memset().
- Use sizeof() in more places instead of hard coded sizes.
- Consistently treat /EncryptMetadata as a boolean.
Change-Id: I8f61e9470f105feda289cc1f3772ced844ce678e
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/63975
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>
diff --git a/core/fpdfapi/parser/cpdf_security_handler.cpp b/core/fpdfapi/parser/cpdf_security_handler.cpp
index 0c98bfb..cb0bd2b 100644
--- a/core/fpdfapi/parser/cpdf_security_handler.cpp
+++ b/core/fpdfapi/parser/cpdf_security_handler.cpp
@@ -51,7 +51,7 @@
if (!fileId.IsEmpty())
CRYPT_MD5Update(&md5, (uint8_t*)fileId.c_str(), fileId.GetLength());
if (!bIgnoreMeta && revision >= 3 &&
- !pEncrypt->GetIntegerFor("EncryptMetadata", 1)) {
+ !pEncrypt->GetBooleanFor("EncryptMetadata", true)) {
uint32_t tag = 0xFFFFFFFF;
CRYPT_MD5Update(&md5, (uint8_t*)&tag, 4);
}
@@ -258,8 +258,7 @@
std::vector<uint8_t> interDigest;
int i = 0;
int iBlockSize = 32;
- CRYPT_aes_context aes;
- memset(&aes, 0, sizeof(aes));
+ CRYPT_aes_context aes = {};
while (i < 64 || i < E[iBufLen - 1] + 32) {
int iRoundSize = password.GetLength() + iBlockSize;
if (vector) {
@@ -358,13 +357,12 @@
if (ekey.GetLength() < 32)
return false;
- CRYPT_aes_context aes;
- memset(&aes, 0, sizeof(aes));
- CRYPT_AESSetKey(&aes, digest, 32, false);
+ CRYPT_aes_context aes = {};
+ CRYPT_AESSetKey(&aes, digest, sizeof(digest), false);
uint8_t iv[16] = {};
CRYPT_AESSetIV(&aes, iv);
CRYPT_AESDecrypt(&aes, m_EncryptKey, ekey.raw_str(), 32);
- CRYPT_AESSetKey(&aes, m_EncryptKey, 32, false);
+ CRYPT_AESSetKey(&aes, m_EncryptKey, sizeof(m_EncryptKey), false);
CRYPT_AESSetIV(&aes, iv);
ByteString perms = m_pEncryptDict->GetStringFor("Perms");
if (perms.IsEmpty())
@@ -558,12 +556,10 @@
CRYPT_SHA256Update(&sha, reinterpret_cast<uint8_t*>(random),
sizeof(random));
CRYPT_SHA256Finish(&sha, m_EncryptKey);
- AES256_SetPassword(pEncryptDict, user_password, false, m_EncryptKey);
+ AES256_SetPassword(pEncryptDict, user_password, false);
if (bDefault)
- AES256_SetPassword(pEncryptDict, owner_password_copy, true, m_EncryptKey);
- AES256_SetPerms(pEncryptDict, m_Permissions,
- pEncryptDict->GetBooleanFor("EncryptMetadata", true),
- m_EncryptKey);
+ AES256_SetPassword(pEncryptDict, owner_password_copy, true);
+ AES256_SetPerms(pEncryptDict);
return;
}
if (bDefault) {
@@ -648,11 +644,10 @@
void CPDF_SecurityHandler::AES256_SetPassword(CPDF_Dictionary* pEncryptDict,
const ByteString& password,
- bool bOwner,
- const uint8_t* key) {
+ bool bOwner) {
CRYPT_sha1_context sha;
CRYPT_SHA1Start(&sha);
- CRYPT_SHA1Update(&sha, key, 32);
+ CRYPT_SHA1Update(&sha, m_EncryptKey, sizeof(m_EncryptKey));
CRYPT_SHA1Update(&sha, (uint8_t*)"hello", 5);
uint8_t digest[20];
@@ -688,30 +683,26 @@
}
CRYPT_SHA256Finish(&sha2, digest1);
}
- CRYPT_aes_context aes;
- memset(&aes, 0, sizeof(aes));
+ CRYPT_aes_context aes = {};
CRYPT_AESSetKey(&aes, digest1, 32, true);
uint8_t iv[16] = {};
CRYPT_AESSetIV(&aes, iv);
- CRYPT_AESEncrypt(&aes, digest1, key, 32);
+ CRYPT_AESEncrypt(&aes, digest1, m_EncryptKey, sizeof(m_EncryptKey));
pEncryptDict->SetNewFor<CPDF_String>(bOwner ? "OE" : "UE",
ByteString(digest1, 32), false);
}
-void CPDF_SecurityHandler::AES256_SetPerms(CPDF_Dictionary* pEncryptDict,
- uint32_t permissions,
- bool bEncryptMetadata,
- const uint8_t* key) {
+void CPDF_SecurityHandler::AES256_SetPerms(CPDF_Dictionary* pEncryptDict) {
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[0] = static_cast<uint8_t>(m_Permissions);
+ buf[1] = static_cast<uint8_t>(m_Permissions >> 8);
+ buf[2] = static_cast<uint8_t>(m_Permissions >> 16);
+ buf[3] = static_cast<uint8_t>(m_Permissions >> 24);
buf[4] = 0xff;
buf[5] = 0xff;
buf[6] = 0xff;
buf[7] = 0xff;
- buf[8] = bEncryptMetadata ? 'T' : 'F';
+ buf[8] = pEncryptDict->GetBooleanFor("EncryptMetadata", true) ? 'T' : 'F';
buf[9] = 'a';
buf[10] = 'd';
buf[11] = 'b';
@@ -721,9 +712,8 @@
uint32_t* buf_random = reinterpret_cast<uint32_t*>(&buf[12]);
FX_Random_GenerateMT(buf_random, 1);
- CRYPT_aes_context aes;
- memset(&aes, 0, sizeof(aes));
- CRYPT_AESSetKey(&aes, key, 32, true);
+ CRYPT_aes_context aes = {};
+ CRYPT_AESSetKey(&aes, m_EncryptKey, sizeof(m_EncryptKey), true);
uint8_t iv[16] = {};
CRYPT_AESSetIV(&aes, iv);
diff --git a/core/fpdfapi/parser/cpdf_security_handler.h b/core/fpdfapi/parser/cpdf_security_handler.h
index ee69283..05eb689 100644
--- a/core/fpdfapi/parser/cpdf_security_handler.h
+++ b/core/fpdfapi/parser/cpdf_security_handler.h
@@ -74,12 +74,8 @@
bool AES256_CheckPassword(const ByteString& password, bool bOwner);
void AES256_SetPassword(CPDF_Dictionary* pEncryptDict,
const ByteString& password,
- bool bOwner,
- const uint8_t* key);
- void AES256_SetPerms(CPDF_Dictionary* pEncryptDict,
- uint32_t permission,
- bool bEncryptMetadata,
- const uint8_t* key);
+ bool bOwner);
+ void AES256_SetPerms(CPDF_Dictionary* pEncryptDict);
void OnCreateInternal(CPDF_Dictionary* pEncryptDict,
const CPDF_Array* pIdArray,
const ByteString& user_password,
