Get rid of FX_LPCSTR cast.

core/src/fpdfapi/fpdf_parser/fpdf_parser_encrypt.cpp

 // 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 <time.h>
 #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());
+    CRYPT_MD5Update(md5, (FX_LPBYTE)okey.c_str(), 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());
+        CRYPT_MD5Update(md5, (FX_LPBYTE)id.c_str(), 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);
@@ skipping 355 matching lines @@
         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_memset32(tmpkey, 0, sizeof(tmpkey));
-        FXSYS_memcpy32(test, (FX_LPCSTR)ukey, copy_len);
+        FXSYS_memcpy32(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);
         }
         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_MD5Update(md5, (FX_LPBYTE)id.c_str(), id.GetLength());
         }
         CRYPT_MD5Finish(md5, ukeybuf);
         return FXSYS_memcmp32(test, ukeybuf, 16) == 0;
     }
-    if (FXSYS_memcmp32((FX_LPVOID)(FX_LPCSTR)ukey, ukeybuf, 16) == 0) {
+    if (FXSYS_memcmp32((FX_LPVOID)ukey.c_str(), 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)
 {
@@ skipping 16 matching lines @@
     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_memset32(okeybuf, 0, sizeof(okeybuf));
-    FXSYS_memcpy32(okeybuf, (FX_LPCSTR)okey, okeylen);
+    FXSYS_memcpy32(okeybuf, okey.c_str(), okeylen);
     if (m_Revision == 2) {
         CRYPT_ArcFourCryptBlock(okeybuf, okeylen, enckey, key_len);
     } else {
         for (int i = 19; i >= 0; i --) {
             FX_BYTE tempkey[32];
             FXSYS_memset32(tempkey, 0, sizeof(tempkey));
             for (int j = 0; j < m_KeyLen; j ++) {
                 tempkey[j] = enckey[j] ^ i;
             }
             CRYPT_ArcFourCryptBlock(okeybuf, okeylen, tempkey, key_len);
@@ skipping 84 matching lines @@
         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());
+            CRYPT_MD5Update(md5, (FX_LPBYTE)id.c_str(), 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);
@@ skipping 370 matching lines @@
     m_pAESContext = NULL;
     m_Cipher = FXCIPHER_NONE;
     m_KeyLen = 0;
 }
 CPDF_StandardCryptoHandler::~CPDF_StandardCryptoHandler()
 {
     if (m_pAESContext) {
         FX_Free(m_pAESContext);
     }
 }