1 // Copyright 2014 PDFium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
6 
7 #include <time.h>
8 #include "../../../include/fpdfapi/fpdf_parser.h"
9 #include "../../../include/fdrm/fx_crypt.h"
10 const FX_BYTE defpasscode[32] = {
11     0x28, 0xbf, 0x4e, 0x5e, 0x4e, 0x75, 0x8a, 0x41,
12     0x64, 0x00, 0x4e, 0x56, 0xff, 0xfa, 0x01, 0x08,
13     0x2e, 0x2e, 0x00, 0xb6, 0xd0, 0x68, 0x3e, 0x80,
14     0x2f, 0x0c, 0xa9, 0xfe, 0x64, 0x53, 0x69, 0x7a
15 };
CalcEncryptKey(CPDF_Dictionary * pEncrypt,FX_LPCBYTE password,FX_DWORD pass_size,FX_LPBYTE key,int keylen,FX_BOOL bIgnoreMeta,CPDF_Array * pIdArray)16 void CalcEncryptKey(CPDF_Dictionary* pEncrypt, FX_LPCBYTE password, FX_DWORD pass_size,
17                     FX_LPBYTE key, int keylen, FX_BOOL bIgnoreMeta, CPDF_Array* pIdArray)
18 {
19     int revision = pEncrypt->GetInteger(FX_BSTRC("R"));
20     FX_BYTE passcode[32];
21     for (FX_DWORD i = 0; i < 32; i ++) {
22         passcode[i] = i < pass_size ? password[i] : defpasscode[i - pass_size];
23     }
24     FX_BYTE md5[100];
25     CRYPT_MD5Start(md5);
26     CRYPT_MD5Update(md5, passcode, 32);
27     CFX_ByteString okey = pEncrypt->GetString(FX_BSTRC("O"));
28     CRYPT_MD5Update(md5, (FX_LPBYTE)okey.c_str(), okey.GetLength());
29     FX_DWORD perm = pEncrypt->GetInteger(FX_BSTRC("P"));
30     CRYPT_MD5Update(md5, (FX_LPBYTE)&perm, 4);
31     if (pIdArray) {
32         CFX_ByteString id = pIdArray->GetString(0);
33         CRYPT_MD5Update(md5, (FX_LPBYTE)id.c_str(), id.GetLength());
34     }
35     if (!bIgnoreMeta && revision >= 3 && !pEncrypt->GetInteger(FX_BSTRC("EncryptMetadata"), 1)) {
36         FX_DWORD tag = (FX_DWORD) - 1;
37         CRYPT_MD5Update(md5, (FX_LPBYTE)&tag, 4);
38     }
39     FX_BYTE digest[16];
40     CRYPT_MD5Finish(md5, digest);
41     FX_DWORD copy_len = keylen;
42     if (copy_len > sizeof(digest)) {
43         copy_len = sizeof(digest);
44     }
45     if (revision >= 3) {
46         for (int i = 0; i < 50; i ++) {
47             CRYPT_MD5Generate(digest, copy_len, digest);
48         }
49     }
50     FXSYS_memset32(key, 0, keylen);
51     FXSYS_memcpy32(key, digest, copy_len);
52 }
CreateCryptoHandler()53 CPDF_CryptoHandler* CPDF_StandardSecurityHandler::CreateCryptoHandler()
54 {
55     return new CPDF_StandardCryptoHandler;
56 }
57 typedef struct _PDF_CRYPTOITEM  {
58     FX_INT32	m_Cipher;
59     FX_INT32	m_KeyLen;
60     FX_BOOL		m_bChecked;
61     CPDF_StandardCryptoHandler*	m_pCryptoHandler;
62 } PDF_CRYPTOITEM;
CPDF_StandardSecurityHandler()63 CPDF_StandardSecurityHandler::CPDF_StandardSecurityHandler()
64 {
65     m_Version = 0;
66     m_Revision = 0;
67     m_pParser = NULL;
68     m_pEncryptDict = NULL;
69     m_bOwner = FALSE;
70     m_Permissions = 0;
71     m_Cipher = FXCIPHER_NONE;
72     m_KeyLen = 0;
73 }
~CPDF_StandardSecurityHandler()74 CPDF_StandardSecurityHandler::~CPDF_StandardSecurityHandler()
75 {
76 }
OnInit(CPDF_Parser * pParser,CPDF_Dictionary * pEncryptDict)77 FX_BOOL CPDF_StandardSecurityHandler::OnInit(CPDF_Parser* pParser, CPDF_Dictionary* pEncryptDict)
78 {
79     m_pParser = pParser;
80     if (!LoadDict(pEncryptDict)) {
81         return FALSE;
82     }
83     if (m_Cipher == FXCIPHER_NONE) {
84         return TRUE;
85     }
86     return CheckSecurity(m_KeyLen);
87 }
CheckSecurity(FX_INT32 key_len)88 FX_BOOL CPDF_StandardSecurityHandler::CheckSecurity(FX_INT32 key_len)
89 {
90     CFX_ByteString password = m_pParser->GetPassword();
91     if (CheckPassword(password, password.GetLength(), TRUE, m_EncryptKey, key_len)) {
92         if (password.IsEmpty()) {
93             if (!CheckPassword(password, password.GetLength(), FALSE, m_EncryptKey, key_len)) {
94                 return FALSE;
95             }
96         }
97         m_bOwner = TRUE;
98         return TRUE;
99     }
100     return CheckPassword(password, password.GetLength(), FALSE, m_EncryptKey, key_len);
101 }
GetPermissions()102 FX_DWORD CPDF_StandardSecurityHandler::GetPermissions()
103 {
104     return m_Permissions;
105 }
_LoadCryptInfo(CPDF_Dictionary * pEncryptDict,FX_BSTR name,int & cipher,int & keylen)106 static FX_BOOL _LoadCryptInfo(CPDF_Dictionary* pEncryptDict, FX_BSTR name, int& cipher, int& keylen)
107 {
108     int Version = pEncryptDict->GetInteger(FX_BSTRC("V"));
109     cipher = FXCIPHER_RC4;
110     keylen = 0;
111     if (Version >= 4) {
112         CPDF_Dictionary* pCryptFilters = pEncryptDict->GetDict(FX_BSTRC("CF"));
113         if (pCryptFilters == NULL) {
114             return FALSE;
115         }
116         if (name == FX_BSTRC("Identity")) {
117             cipher = FXCIPHER_NONE;
118         } else {
119             CPDF_Dictionary* pDefFilter = pCryptFilters->GetDict(name);
120             if (pDefFilter == NULL) {
121                 return FALSE;
122             }
123             int nKeyBits = 0;
124             if (Version == 4) {
125                 nKeyBits = pDefFilter->GetInteger(FX_BSTRC("Length"), 0);
126                 if (nKeyBits == 0) {
127                     nKeyBits = pEncryptDict->GetInteger(FX_BSTRC("Length"), 128);
128                 }
129             } else {
130                 nKeyBits = pEncryptDict->GetInteger(FX_BSTRC("Length"), 256);
131             }
132             if (nKeyBits < 40) {
133                 nKeyBits *= 8;
134             }
135             keylen = nKeyBits / 8;
136             CFX_ByteString cipher_name = pDefFilter->GetString(FX_BSTRC("CFM"));
137             if (cipher_name == FX_BSTRC("AESV2") || cipher_name == FX_BSTRC("AESV3")) {
138                 cipher = FXCIPHER_AES;
139             }
140         }
141     } else {
142         keylen = Version > 1 ? pEncryptDict->GetInteger(FX_BSTRC("Length"), 40) / 8 : 5;
143     }
144     if (keylen > 32 || keylen < 0) {
145         return FALSE;
146     }
147     return TRUE;
148 }
LoadDict(CPDF_Dictionary * pEncryptDict)149 FX_BOOL CPDF_StandardSecurityHandler::LoadDict(CPDF_Dictionary* pEncryptDict)
150 {
151     m_pEncryptDict = pEncryptDict;
152     m_bOwner = FALSE;
153     m_Version = pEncryptDict->GetInteger(FX_BSTRC("V"));
154     m_Revision = pEncryptDict->GetInteger(FX_BSTRC("R"));
155     m_Permissions = pEncryptDict->GetInteger(FX_BSTRC("P"), -1);
156     if (m_Version < 4) {
157         return _LoadCryptInfo(pEncryptDict, CFX_ByteString(), m_Cipher, m_KeyLen);
158     }
159     CFX_ByteString stmf_name = pEncryptDict->GetString(FX_BSTRC("StmF"));
160     CFX_ByteString strf_name = pEncryptDict->GetString(FX_BSTRC("StrF"));
161     if (stmf_name != strf_name) {
162         return FALSE;
163     }
164     if (!_LoadCryptInfo(pEncryptDict, strf_name, m_Cipher, m_KeyLen)) {
165         return FALSE;
166     }
167     return TRUE;
168 }
LoadDict(CPDF_Dictionary * pEncryptDict,FX_DWORD type,int & cipher,int & key_len)169 FX_BOOL CPDF_StandardSecurityHandler::LoadDict(CPDF_Dictionary* pEncryptDict, FX_DWORD type, int& cipher, int& key_len)
170 {
171     m_pEncryptDict = pEncryptDict;
172     m_bOwner = FALSE;
173     m_Version = pEncryptDict->GetInteger(FX_BSTRC("V"));
174     m_Revision = pEncryptDict->GetInteger(FX_BSTRC("R"));
175     m_Permissions = pEncryptDict->GetInteger(FX_BSTRC("P"), -1);
176     CFX_ByteString strf_name, stmf_name;
177     if (m_Version >= 4) {
178         stmf_name = pEncryptDict->GetString(FX_BSTRC("StmF"));
179         strf_name = pEncryptDict->GetString(FX_BSTRC("StrF"));
180         if (stmf_name != strf_name) {
181             return FALSE;
182         }
183     }
184     if (!_LoadCryptInfo(pEncryptDict, strf_name, cipher, key_len)) {
185         return FALSE;
186     }
187     m_Cipher = cipher;
188     m_KeyLen = key_len;
189     return TRUE;
190     return TRUE;
191 }
GetCryptInfo(int & cipher,FX_LPCBYTE & buffer,int & keylen)192 FX_BOOL CPDF_StandardSecurityHandler::GetCryptInfo(int& cipher, FX_LPCBYTE& buffer, int& keylen)
193 {
194     cipher = m_Cipher;
195     buffer = m_EncryptKey;
196     keylen = m_KeyLen;
197     return TRUE;
198 }
199 #define FX_GET_32WORD(n,b,i)								\
200     {														\
201         (n) = (FX_DWORD)(( (FX_UINT64) (b)[(i)] << 24 )			\
202                          | ( (FX_UINT64) (b)[(i) + 1] << 16 )					\
203                          | ( (FX_UINT64) (b)[(i) + 2] <<  8 )					\
204                          | ( (FX_UINT64) (b)[(i) + 3]       ));					\
205     }
BigOrder64BitsMod3(FX_LPBYTE data)206 int BigOrder64BitsMod3(FX_LPBYTE data)
207 {
208     FX_UINT64 ret = 0;
209     for (int i = 0; i < 4; ++i) {
210         FX_DWORD value;
211         FX_GET_32WORD(value, data, 4 * i);
212         ret <<= 32;
213         ret |= value;
214         ret %= 3;
215     }
216     return (int)ret;
217 }
Revision6_Hash(FX_LPCBYTE password,FX_DWORD size,FX_LPCBYTE salt,FX_LPCBYTE vector,FX_LPBYTE hash)218 void Revision6_Hash(FX_LPCBYTE password, FX_DWORD size, FX_LPCBYTE salt, FX_LPCBYTE vector, FX_LPBYTE hash)
219 {
220     int iBlockSize = 32;
221     FX_BYTE sha[128];
222     CRYPT_SHA256Start(sha);
223     CRYPT_SHA256Update(sha, password, size);
224     CRYPT_SHA256Update(sha, salt, 8);
225     if (vector) {
226         CRYPT_SHA256Update(sha, vector, 48);
227     }
228     FX_BYTE digest[32];
229     CRYPT_SHA256Finish(sha, digest);
230     CFX_ByteTextBuf buf;
231     FX_LPBYTE input = digest;
232     FX_LPBYTE key = input;
233     FX_LPBYTE iv = input + 16;
234     FX_LPBYTE E = buf.GetBuffer();
235     int iBufLen = buf.GetLength();
236     CFX_ByteTextBuf interDigest;
237     int i = 0;
238     FX_LPBYTE aes = FX_Alloc(FX_BYTE, 2048);
239     while (i < 64 || i < E[iBufLen - 1]  + 32) {
240         int iRoundSize = size + iBlockSize;
241         if (vector) {
242             iRoundSize += 48;
243         }
244         iBufLen = iRoundSize * 64;
245         buf.EstimateSize(iBufLen);
246         E = buf.GetBuffer();
247         CFX_ByteTextBuf content;
248         for (int j = 0; j < 64; ++j) {
249             content.AppendBlock(password, size);
250             content.AppendBlock(input, iBlockSize);
251             if (vector) {
252                 content.AppendBlock(vector, 48);
253             }
254         }
255         CRYPT_AESSetKey(aes, 16, key, 16, TRUE);
256         CRYPT_AESSetIV(aes, iv);
257         CRYPT_AESEncrypt(aes, E, content.GetBuffer(), iBufLen);
258         int iHash = 0;
259         switch (BigOrder64BitsMod3(E)) {
260             case 0:
261                 iHash = 0;
262                 iBlockSize = 32;
263                 break;
264             case 1:
265                 iHash = 1;
266                 iBlockSize = 48;
267                 break;
268             default:
269                 iHash = 2;
270                 iBlockSize = 64;
271                 break;
272         }
273         interDigest.EstimateSize(iBlockSize);
274         input = interDigest.GetBuffer();
275         if (iHash == 0) {
276             CRYPT_SHA256Generate(E, iBufLen, input);
277         } else if (iHash == 1) {
278             CRYPT_SHA384Generate(E, iBufLen, input);
279         } else if (iHash == 2) {
280             CRYPT_SHA512Generate(E, iBufLen, input);
281         }
282         key = input;
283         iv = input + 16;
284         ++i;
285     }
286     FX_Free(aes);
287     if (hash) {
288         FXSYS_memcpy32(hash, input, 32);
289     }
290 }
AES256_CheckPassword(FX_LPCBYTE password,FX_DWORD size,FX_BOOL bOwner,FX_LPBYTE key)291 FX_BOOL CPDF_StandardSecurityHandler::AES256_CheckPassword(FX_LPCBYTE password, FX_DWORD size,
292         FX_BOOL bOwner, FX_LPBYTE key)
293 {
294     CFX_ByteString okey = m_pEncryptDict ? m_pEncryptDict->GetString(FX_BSTRC("O")) : CFX_ByteString();
295     if (okey.GetLength() < 48) {
296         return FALSE;
297     }
298     CFX_ByteString ukey = m_pEncryptDict ? m_pEncryptDict->GetString(FX_BSTRC("U")) : CFX_ByteString();
299     if (ukey.GetLength() < 48) {
300         return FALSE;
301     }
302     FX_LPCBYTE pkey = bOwner ? (FX_LPCBYTE)okey : (FX_LPCBYTE)ukey;
303     FX_BYTE sha[128];
304     FX_BYTE digest[32];
305     if (m_Revision >= 6) {
306         Revision6_Hash(password, size, (FX_LPCBYTE)pkey + 32, (bOwner ? (FX_LPCBYTE)ukey : NULL), digest);
307     } else {
308         CRYPT_SHA256Start(sha);
309         CRYPT_SHA256Update(sha, password, size);
310         CRYPT_SHA256Update(sha, pkey + 32, 8);
311         if (bOwner) {
312             CRYPT_SHA256Update(sha, ukey, 48);
313         }
314         CRYPT_SHA256Finish(sha, digest);
315     }
316     if (FXSYS_memcmp32(digest, pkey, 32) != 0) {
317         return FALSE;
318     }
319     if (key == NULL) {
320         return TRUE;
321     }
322     if (m_Revision >= 6) {
323         Revision6_Hash(password, size, (FX_LPCBYTE)pkey + 40, (bOwner ? (FX_LPCBYTE)ukey : NULL), digest);
324     } else {
325         CRYPT_SHA256Start(sha);
326         CRYPT_SHA256Update(sha, password, size);
327         CRYPT_SHA256Update(sha, pkey + 40, 8);
328         if (bOwner) {
329             CRYPT_SHA256Update(sha, ukey, 48);
330         }
331         CRYPT_SHA256Finish(sha, digest);
332     }
333     CFX_ByteString ekey = m_pEncryptDict ? m_pEncryptDict->GetString(bOwner ? FX_BSTRC("OE") : FX_BSTRC("UE")) : CFX_ByteString();
334     if (ekey.GetLength() < 32) {
335         return FALSE;
336     }
337     FX_BYTE* aes = FX_Alloc(FX_BYTE, 2048);
338     CRYPT_AESSetKey(aes, 16, digest, 32, FALSE);
339     FX_BYTE iv[16];
340     FXSYS_memset32(iv, 0, 16);
341     CRYPT_AESSetIV(aes, iv);
342     CRYPT_AESDecrypt(aes, key, ekey, 32);
343     CRYPT_AESSetKey(aes, 16, key, 32, FALSE);
344     CRYPT_AESSetIV(aes, iv);
345     CFX_ByteString perms = m_pEncryptDict->GetString(FX_BSTRC("Perms"));
346     if (perms.IsEmpty()) {
347         return FALSE;
348     }
349     FX_BYTE perms_buf[16];
350     FXSYS_memset32(perms_buf, 0, sizeof(perms_buf));
351     FX_DWORD copy_len = sizeof(perms_buf);
352     if (copy_len > (FX_DWORD)perms.GetLength()) {
353         copy_len = perms.GetLength();
354     }
355     FXSYS_memcpy32(perms_buf, (FX_LPCBYTE)perms, copy_len);
356     FX_BYTE buf[16];
357     CRYPT_AESDecrypt(aes, buf, perms_buf, 16);
358     FX_Free(aes);
359     if (buf[9] != 'a' || buf[10] != 'd' || buf[11] != 'b') {
360         return FALSE;
361     }
362     if (FXDWORD_GET_LSBFIRST(buf) != m_Permissions) {
363         return FALSE;
364     }
365     if ((buf[8] == 'T' && !IsMetadataEncrypted()) || (buf[8] == 'F' && IsMetadataEncrypted())) {
366         return FALSE;
367     }
368     return TRUE;
369 }
CheckPassword(FX_LPCBYTE password,FX_DWORD pass_size,FX_BOOL bOwner,FX_LPBYTE key)370 int CPDF_StandardSecurityHandler::CheckPassword(FX_LPCBYTE password, FX_DWORD pass_size, FX_BOOL bOwner, FX_LPBYTE key)
371 {
372     return CheckPassword(password, pass_size, bOwner, key, m_KeyLen);
373 }
CheckPassword(FX_LPCBYTE password,FX_DWORD size,FX_BOOL bOwner,FX_LPBYTE key,FX_INT32 key_len)374 int CPDF_StandardSecurityHandler::CheckPassword(FX_LPCBYTE password, FX_DWORD size, FX_BOOL bOwner, FX_LPBYTE key, FX_INT32 key_len)
375 {
376     if (m_Revision >= 5) {
377         return AES256_CheckPassword(password, size, bOwner, key);
378     }
379     FX_BYTE keybuf[32];
380     if (key == NULL) {
381         key = keybuf;
382     }
383     if (bOwner) {
384         return CheckOwnerPassword(password, size, key, key_len);
385     }
386     return CheckUserPassword(password, size, FALSE, key, key_len) || CheckUserPassword(password, size, TRUE, key, key_len);
387 }
CheckUserPassword(FX_LPCBYTE password,FX_DWORD pass_size,FX_BOOL bIgnoreEncryptMeta,FX_LPBYTE key,FX_INT32 key_len)388 FX_BOOL CPDF_StandardSecurityHandler::CheckUserPassword(FX_LPCBYTE password, FX_DWORD pass_size,
389         FX_BOOL bIgnoreEncryptMeta, FX_LPBYTE key, FX_INT32 key_len)
390 {
391     CalcEncryptKey(m_pEncryptDict, password, pass_size, key, key_len, bIgnoreEncryptMeta,
392                    m_pParser->GetIDArray());
393     CFX_ByteString ukey = m_pEncryptDict ? m_pEncryptDict->GetString(FX_BSTRC("U")) : CFX_ByteString();
394     if (ukey.GetLength() < 16) {
395         return FALSE;
396     }
397     FX_BYTE ukeybuf[32];
398     if (m_Revision == 2) {
399         FXSYS_memcpy32(ukeybuf, defpasscode, 32);
400         CRYPT_ArcFourCryptBlock(ukeybuf, 32, key, key_len);
401     } else {
402         FX_BYTE test[32], tmpkey[32];
403         FX_DWORD copy_len = sizeof(test);
404         if (copy_len > (FX_DWORD)ukey.GetLength()) {
405             copy_len = ukey.GetLength();
406         }
407         FXSYS_memset32(test, 0, sizeof(test));
408         FXSYS_memset32(tmpkey, 0, sizeof(tmpkey));
409         FXSYS_memcpy32(test, ukey.c_str(), copy_len);
410         for (int i = 19; i >= 0; i --) {
411             for (int j = 0; j < key_len; j ++) {
412                 tmpkey[j] = key[j] ^ i;
413             }
414             CRYPT_ArcFourCryptBlock(test, 32, tmpkey, key_len);
415         }
416         FX_BYTE md5[100];
417         CRYPT_MD5Start(md5);
418         CRYPT_MD5Update(md5, defpasscode, 32);
419         CPDF_Array* pIdArray = m_pParser->GetIDArray();
420         if (pIdArray) {
421             CFX_ByteString id = pIdArray->GetString(0);
422             CRYPT_MD5Update(md5, (FX_LPBYTE)id.c_str(), id.GetLength());
423         }
424         CRYPT_MD5Finish(md5, ukeybuf);
425         return FXSYS_memcmp32(test, ukeybuf, 16) == 0;
426     }
427     if (FXSYS_memcmp32((FX_LPVOID)ukey.c_str(), ukeybuf, 16) == 0) {
428         return TRUE;
429     }
430     return FALSE;
431 }
GetUserPassword(FX_LPCBYTE owner_pass,FX_DWORD pass_size)432 CFX_ByteString CPDF_StandardSecurityHandler::GetUserPassword(FX_LPCBYTE owner_pass, FX_DWORD pass_size)
433 {
434     return GetUserPassword(owner_pass, pass_size, m_KeyLen);
435 }
GetUserPassword(FX_LPCBYTE owner_pass,FX_DWORD pass_size,FX_INT32 key_len)436 CFX_ByteString CPDF_StandardSecurityHandler::GetUserPassword(FX_LPCBYTE owner_pass, FX_DWORD pass_size, FX_INT32 key_len)
437 {
438     CFX_ByteString okey = m_pEncryptDict->GetString(FX_BSTRC("O"));
439     FX_BYTE passcode[32];
440     FX_DWORD i;
441     for (i = 0; i < 32; i ++) {
442         passcode[i] = i < pass_size ? owner_pass[i] : defpasscode[i - pass_size];
443     }
444     FX_BYTE digest[16];
445     CRYPT_MD5Generate(passcode, 32, digest);
446     if (m_Revision >= 3) {
447         for (int i = 0; i < 50; i ++) {
448             CRYPT_MD5Generate(digest, 16, digest);
449         }
450     }
451     FX_BYTE enckey[32];
452     FXSYS_memset32(enckey, 0, sizeof(enckey));
453     FX_DWORD copy_len = key_len;
454     if (copy_len > sizeof(digest)) {
455         copy_len = sizeof(digest);
456     }
457     FXSYS_memcpy32(enckey, digest, copy_len);
458     int okeylen = okey.GetLength();
459     if (okeylen > 32) {
460         okeylen = 32;
461     }
462     FX_BYTE okeybuf[64];
463     FXSYS_memset32(okeybuf, 0, sizeof(okeybuf));
464     FXSYS_memcpy32(okeybuf, okey.c_str(), okeylen);
465     if (m_Revision == 2) {
466         CRYPT_ArcFourCryptBlock(okeybuf, okeylen, enckey, key_len);
467     } else {
468         for (int i = 19; i >= 0; i --) {
469             FX_BYTE tempkey[32];
470             FXSYS_memset32(tempkey, 0, sizeof(tempkey));
471             for (int j = 0; j < m_KeyLen; j ++) {
472                 tempkey[j] = enckey[j] ^ i;
473             }
474             CRYPT_ArcFourCryptBlock(okeybuf, okeylen, tempkey, key_len);
475         }
476     }
477     int len = 32;
478     while (len && defpasscode[len - 1] == okeybuf[len - 1]) {
479         len --;
480     }
481     return CFX_ByteString(okeybuf, len);
482 }
CheckOwnerPassword(FX_LPCBYTE password,FX_DWORD pass_size,FX_LPBYTE key,FX_INT32 key_len)483 FX_BOOL CPDF_StandardSecurityHandler::CheckOwnerPassword(FX_LPCBYTE password, FX_DWORD pass_size,
484         FX_LPBYTE key, FX_INT32 key_len)
485 {
486     CFX_ByteString user_pass = GetUserPassword(password, pass_size, key_len);
487     if (CheckUserPassword(user_pass, user_pass.GetLength(), FALSE, key, key_len)) {
488         return TRUE;
489     }
490     return CheckUserPassword(user_pass, user_pass.GetLength(), TRUE, key, key_len);
491 }
IsMetadataEncrypted()492 FX_BOOL CPDF_StandardSecurityHandler::IsMetadataEncrypted()
493 {
494     return m_pEncryptDict->GetBoolean(FX_BSTRC("EncryptMetadata"), TRUE);
495 }
FPDF_CreateStandardSecurityHandler()496 CPDF_SecurityHandler* FPDF_CreateStandardSecurityHandler()
497 {
498     return new CPDF_StandardSecurityHandler;
499 }
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)500 void CPDF_StandardSecurityHandler::OnCreate(CPDF_Dictionary* pEncryptDict, CPDF_Array* pIdArray,
501         FX_LPCBYTE user_pass, FX_DWORD user_size,
502         FX_LPCBYTE owner_pass, FX_DWORD owner_size, FX_BOOL bDefault, FX_DWORD type)
503 {
504     int cipher = 0, key_len = 0;
505     if (!LoadDict(pEncryptDict, type, cipher, key_len)) {
506         return;
507     }
508     if (bDefault && (owner_pass == NULL || owner_size == 0)) {
509         owner_pass = user_pass;
510         owner_size = user_size;
511     }
512     if (m_Revision >= 5) {
513         int t = (int)time(NULL);
514         FX_BYTE sha[128];
515         CRYPT_SHA256Start(sha);
516         CRYPT_SHA256Update(sha, (FX_BYTE*)&t, sizeof t);
517         CRYPT_SHA256Update(sha, m_EncryptKey, 32);
518         CRYPT_SHA256Update(sha, (FX_BYTE*)"there", 5);
519         CRYPT_SHA256Finish(sha, m_EncryptKey);
520         AES256_SetPassword(pEncryptDict, user_pass, user_size, FALSE, m_EncryptKey);
521         if (bDefault) {
522             AES256_SetPassword(pEncryptDict, owner_pass, owner_size, TRUE, m_EncryptKey);
523             AES256_SetPerms(pEncryptDict, m_Permissions, pEncryptDict->GetBoolean(FX_BSTRC("EncryptMetadata"), TRUE), m_EncryptKey);
524         }
525         return;
526     }
527     if (bDefault) {
528         FX_BYTE passcode[32];
529         FX_DWORD i;
530         for (i = 0; i < 32; i ++) {
531             passcode[i] = i < owner_size ? owner_pass[i] : defpasscode[i - owner_size];
532         }
533         FX_BYTE digest[16];
534         CRYPT_MD5Generate(passcode, 32, digest);
535         if (m_Revision >= 3) {
536             for (int i = 0; i < 50; i ++) {
537                 CRYPT_MD5Generate(digest, 16, digest);
538             }
539         }
540         FX_BYTE enckey[32];
541         FXSYS_memcpy32(enckey, digest, key_len);
542         for (i = 0; i < 32; i ++) {
543             passcode[i] = i < user_size ? user_pass[i] : defpasscode[i - user_size];
544         }
545         CRYPT_ArcFourCryptBlock(passcode, 32, enckey, key_len);
546         FX_BYTE tempkey[32];
547         if (m_Revision >= 3) {
548             for (i = 1; i <= 19; i ++) {
549                 for (int j = 0; j < key_len; j ++) {
550                     tempkey[j] = enckey[j] ^ (FX_BYTE)i;
551                 }
552                 CRYPT_ArcFourCryptBlock(passcode, 32, tempkey, key_len);
553             }
554         }
555         pEncryptDict->SetAtString(FX_BSTRC("O"), CFX_ByteString(passcode, 32));
556     }
557     CalcEncryptKey(m_pEncryptDict, (FX_LPBYTE)user_pass, user_size, m_EncryptKey, key_len, FALSE, pIdArray);
558     if (m_Revision < 3) {
559         FX_BYTE tempbuf[32];
560         FXSYS_memcpy32(tempbuf, defpasscode, 32);
561         CRYPT_ArcFourCryptBlock(tempbuf, 32, m_EncryptKey, key_len);
562         pEncryptDict->SetAtString(FX_BSTRC("U"), CFX_ByteString(tempbuf, 32));
563     } else {
564         FX_BYTE md5[100];
565         CRYPT_MD5Start(md5);
566         CRYPT_MD5Update(md5, defpasscode, 32);
567         if (pIdArray) {
568             CFX_ByteString id = pIdArray->GetString(0);
569             CRYPT_MD5Update(md5, (FX_LPBYTE)id.c_str(), id.GetLength());
570         }
571         FX_BYTE digest[32];
572         CRYPT_MD5Finish(md5, digest);
573         CRYPT_ArcFourCryptBlock(digest, 16, m_EncryptKey, key_len);
574         FX_BYTE tempkey[32];
575         for (int i = 1; i <= 19; i ++) {
576             for (int j = 0; j < key_len; j ++) {
577                 tempkey[j] = m_EncryptKey[j] ^ (FX_BYTE)i;
578             }
579             CRYPT_ArcFourCryptBlock(digest, 16, tempkey, key_len);
580         }
581         CRYPT_MD5Generate(digest, 16, digest + 16);
582         pEncryptDict->SetAtString(FX_BSTRC("U"), CFX_ByteString(digest, 32));
583     }
584 }
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)585 void CPDF_StandardSecurityHandler::OnCreate(CPDF_Dictionary* pEncryptDict, CPDF_Array* pIdArray,
586         FX_LPCBYTE user_pass, FX_DWORD user_size,
587         FX_LPCBYTE owner_pass, FX_DWORD owner_size, FX_DWORD type)
588 {
589     OnCreate(pEncryptDict, pIdArray, user_pass, user_size, owner_pass, owner_size, TRUE, type);
590 }
OnCreate(CPDF_Dictionary * pEncryptDict,CPDF_Array * pIdArray,FX_LPCBYTE user_pass,FX_DWORD user_size,FX_DWORD type)591 void CPDF_StandardSecurityHandler::OnCreate(CPDF_Dictionary* pEncryptDict, CPDF_Array* pIdArray, FX_LPCBYTE user_pass, FX_DWORD user_size, FX_DWORD type)
592 {
593     OnCreate(pEncryptDict, pIdArray, user_pass, user_size, NULL, 0, FALSE, type);
594 }
AES256_SetPassword(CPDF_Dictionary * pEncryptDict,FX_LPCBYTE password,FX_DWORD size,FX_BOOL bOwner,FX_LPCBYTE key)595 void CPDF_StandardSecurityHandler::AES256_SetPassword(CPDF_Dictionary* pEncryptDict, FX_LPCBYTE password, FX_DWORD size, FX_BOOL bOwner, FX_LPCBYTE key)
596 {
597     FX_BYTE sha[128];
598     CRYPT_SHA1Start(sha);
599     CRYPT_SHA1Update(sha, key, 32);
600     CRYPT_SHA1Update(sha, (FX_BYTE*)"hello", 5);
601     FX_BYTE digest[20];
602     CRYPT_SHA1Finish(sha, digest);
603     CFX_ByteString ukey = pEncryptDict->GetString(FX_BSTRC("U"));
604     FX_BYTE digest1[48];
605     if (m_Revision >= 6) {
606         Revision6_Hash(password, size, digest, (bOwner ? (FX_LPCBYTE)ukey : NULL), digest1);
607     } else {
608         CRYPT_SHA256Start(sha);
609         CRYPT_SHA256Update(sha, password, size);
610         CRYPT_SHA256Update(sha, digest, 8);
611         if (bOwner) {
612             CRYPT_SHA256Update(sha, ukey, ukey.GetLength());
613         }
614         CRYPT_SHA256Finish(sha, digest1);
615     }
616     FXSYS_memcpy32(digest1 + 32, digest, 16);
617     pEncryptDict->SetAtString(bOwner ? FX_BSTRC("O") : FX_BSTRC("U"), CFX_ByteString(digest1, 48));
618     if (m_Revision >= 6) {
619         Revision6_Hash(password, size, digest + 8, (bOwner ? (FX_LPCBYTE)ukey : NULL), digest1);
620     } else {
621         CRYPT_SHA256Start(sha);
622         CRYPT_SHA256Update(sha, password, size);
623         CRYPT_SHA256Update(sha, digest + 8, 8);
624         if (bOwner) {
625             CRYPT_SHA256Update(sha, ukey, ukey.GetLength());
626         }
627         CRYPT_SHA256Finish(sha, digest1);
628     }
629     FX_BYTE* aes = FX_Alloc(FX_BYTE, 2048);
630     CRYPT_AESSetKey(aes, 16, digest1, 32, TRUE);
631     FX_BYTE iv[16];
632     FXSYS_memset32(iv, 0, 16);
633     CRYPT_AESSetIV(aes, iv);
634     CRYPT_AESEncrypt(aes, digest1, key, 32);
635     FX_Free(aes);
636     pEncryptDict->SetAtString(bOwner ? FX_BSTRC("OE") : FX_BSTRC("UE"), CFX_ByteString(digest1, 32));
637 }
AES256_SetPerms(CPDF_Dictionary * pEncryptDict,FX_DWORD permissions,FX_BOOL bEncryptMetadata,FX_LPCBYTE key)638 void CPDF_StandardSecurityHandler::AES256_SetPerms(CPDF_Dictionary* pEncryptDict, FX_DWORD permissions,
639         FX_BOOL bEncryptMetadata, FX_LPCBYTE key)
640 {
641     FX_BYTE buf[16];
642     buf[0] = (FX_BYTE)permissions;
643     buf[1] = (FX_BYTE)(permissions >> 8);
644     buf[2] = (FX_BYTE)(permissions >> 16);
645     buf[3] = (FX_BYTE)(permissions >> 24);
646     buf[4] = 0xff;
647     buf[5] = 0xff;
648     buf[6] = 0xff;
649     buf[7] = 0xff;
650     buf[8] = bEncryptMetadata ? 'T' : 'F';
651     buf[9] = 'a';
652     buf[10] = 'd';
653     buf[11] = 'b';
654     FX_BYTE* aes = FX_Alloc(FX_BYTE, 2048);
655     CRYPT_AESSetKey(aes, 16, key, 32, TRUE);
656     FX_BYTE iv[16], buf1[16];
657     FXSYS_memset32(iv, 0, 16);
658     CRYPT_AESSetIV(aes, iv);
659     CRYPT_AESEncrypt(aes, buf1, buf, 16);
660     FX_Free(aes);
661     pEncryptDict->SetAtString(FX_BSTRC("Perms"), CFX_ByteString(buf1, 16));
662 }
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)663 void CPDF_StandardCryptoHandler::CryptBlock(FX_BOOL bEncrypt, FX_DWORD objnum, FX_DWORD gennum, FX_LPCBYTE src_buf, FX_DWORD src_size,
664         FX_LPBYTE dest_buf, FX_DWORD& dest_size)
665 {
666     if (m_Cipher == FXCIPHER_NONE) {
667         FXSYS_memcpy32(dest_buf, src_buf, src_size);
668         return;
669     }
670     FX_BYTE realkey[16];
671     int realkeylen = 16;
672     if (m_Cipher != FXCIPHER_AES || m_KeyLen != 32) {
673         FX_BYTE key1[32];
674         FXSYS_memcpy32(key1, m_EncryptKey, m_KeyLen);
675         key1[m_KeyLen + 0] = (FX_BYTE)objnum;
676         key1[m_KeyLen + 1] = (FX_BYTE)(objnum >> 8);
677         key1[m_KeyLen + 2] = (FX_BYTE)(objnum >> 16);
678         key1[m_KeyLen + 3] = (FX_BYTE)gennum;
679         key1[m_KeyLen + 4] = (FX_BYTE)(gennum >> 8);
680         FXSYS_memcpy32(key1 + m_KeyLen, &objnum, 3);
681         FXSYS_memcpy32(key1 + m_KeyLen + 3, &gennum, 2);
682         if (m_Cipher == FXCIPHER_AES) {
683             FXSYS_memcpy32(key1 + m_KeyLen + 5, "sAlT", 4);
684         }
685         CRYPT_MD5Generate(key1, m_Cipher == FXCIPHER_AES ? m_KeyLen + 9 : m_KeyLen + 5, realkey);
686         realkeylen = m_KeyLen + 5;
687         if (realkeylen > 16) {
688             realkeylen = 16;
689         }
690     }
691     if (m_Cipher == FXCIPHER_AES) {
692         CRYPT_AESSetKey(m_pAESContext, 16, m_KeyLen == 32 ? m_EncryptKey : realkey, m_KeyLen, bEncrypt);
693         if (bEncrypt) {
694             FX_BYTE iv[16];
695             for (int i = 0; i < 16; i ++) {
696                 iv[i] = (FX_BYTE)rand();
697             }
698             CRYPT_AESSetIV(m_pAESContext, iv);
699             FXSYS_memcpy32(dest_buf, iv, 16);
700             int nblocks = src_size / 16;
701             CRYPT_AESEncrypt(m_pAESContext, dest_buf + 16, src_buf, nblocks * 16);
702             FX_BYTE padding[16];
703             FXSYS_memcpy32(padding, src_buf + nblocks * 16, src_size % 16);
704             FXSYS_memset8(padding + src_size % 16, 16 - src_size % 16, 16 - src_size % 16);
705             CRYPT_AESEncrypt(m_pAESContext, dest_buf + nblocks * 16 + 16, padding, 16);
706             dest_size = 32 + nblocks * 16;
707         } else {
708             CRYPT_AESSetIV(m_pAESContext, src_buf);
709             CRYPT_AESDecrypt(m_pAESContext, dest_buf, src_buf + 16, src_size - 16);
710             dest_size = src_size - 16;
711             dest_size -= dest_buf[dest_size - 1];
712         }
713     } else {
714         ASSERT(dest_size == src_size);
715         if (dest_buf != src_buf) {
716             FXSYS_memcpy32(dest_buf, src_buf, src_size);
717         }
718         CRYPT_ArcFourCryptBlock(dest_buf, dest_size, realkey, realkeylen);
719     }
720 }
721 typedef struct _AESCryptContext {
722     FX_BYTE		m_Context[2048];
723     FX_BOOL		m_bIV;
724     FX_BYTE		m_Block[16];
725     FX_DWORD	m_BlockOffset;
726 } AESCryptContext;
CryptStart(FX_DWORD objnum,FX_DWORD gennum,FX_BOOL bEncrypt)727 FX_LPVOID CPDF_StandardCryptoHandler::CryptStart(FX_DWORD objnum, FX_DWORD gennum, FX_BOOL bEncrypt)
728 {
729     if (m_Cipher == FXCIPHER_NONE) {
730         return this;
731     }
732     if (m_Cipher == FXCIPHER_AES && m_KeyLen == 32) {
733         AESCryptContext* pContext = FX_Alloc(AESCryptContext, 1);
734         pContext->m_bIV = TRUE;
735         pContext->m_BlockOffset = 0;
736         CRYPT_AESSetKey(pContext->m_Context, 16, m_EncryptKey, 32, bEncrypt);
737         if (bEncrypt) {
738             for (int i = 0; i < 16; i ++) {
739                 pContext->m_Block[i] = (FX_BYTE)rand();
740             }
741             CRYPT_AESSetIV(pContext->m_Context, pContext->m_Block);
742         }
743         return pContext;
744     }
745     FX_BYTE key1[48];
746     FXSYS_memcpy32(key1, m_EncryptKey, m_KeyLen);
747     FXSYS_memcpy32(key1 + m_KeyLen, &objnum, 3);
748     FXSYS_memcpy32(key1 + m_KeyLen + 3, &gennum, 2);
749     if (m_Cipher == FXCIPHER_AES) {
750         FXSYS_memcpy32(key1 + m_KeyLen + 5, "sAlT", 4);
751     }
752     FX_BYTE realkey[16];
753     CRYPT_MD5Generate(key1, m_Cipher == FXCIPHER_AES ? m_KeyLen + 9 : m_KeyLen + 5, realkey);
754     int realkeylen = m_KeyLen + 5;
755     if (realkeylen > 16) {
756         realkeylen = 16;
757     }
758     if (m_Cipher == FXCIPHER_AES) {
759         AESCryptContext* pContext = FX_Alloc(AESCryptContext, 1);
760         pContext->m_bIV = TRUE;
761         pContext->m_BlockOffset = 0;
762         CRYPT_AESSetKey(pContext->m_Context, 16, realkey, 16, bEncrypt);
763         if (bEncrypt) {
764             for (int i = 0; i < 16; i ++) {
765                 pContext->m_Block[i] = (FX_BYTE)rand();
766             }
767             CRYPT_AESSetIV(pContext->m_Context, pContext->m_Block);
768         }
769         return pContext;
770     }
771     void* pContext = FX_Alloc(FX_BYTE, 1040);
772     CRYPT_ArcFourSetup(pContext, realkey, realkeylen);
773     return pContext;
774 }
CryptStream(FX_LPVOID context,FX_LPCBYTE src_buf,FX_DWORD src_size,CFX_BinaryBuf & dest_buf,FX_BOOL bEncrypt)775 FX_BOOL CPDF_StandardCryptoHandler::CryptStream(FX_LPVOID context, FX_LPCBYTE src_buf, FX_DWORD src_size, CFX_BinaryBuf& dest_buf, FX_BOOL bEncrypt)
776 {
777     if (!context) {
778         return FALSE;
779     }
780     if (m_Cipher == FXCIPHER_NONE) {
781         dest_buf.AppendBlock(src_buf, src_size);
782         return TRUE;
783     }
784     if (m_Cipher == FXCIPHER_RC4) {
785         int old_size = dest_buf.GetSize();
786         dest_buf.AppendBlock(src_buf, src_size);
787         CRYPT_ArcFourCrypt(context, dest_buf.GetBuffer() + old_size, src_size);
788         return TRUE;
789     }
790     AESCryptContext* pContext = (AESCryptContext*)context;
791     if (pContext->m_bIV && bEncrypt) {
792         dest_buf.AppendBlock(pContext->m_Block, 16);
793         pContext->m_bIV = FALSE;
794     }
795     FX_DWORD src_off = 0;
796     FX_DWORD src_left = src_size;
797     while (1) {
798         FX_DWORD copy_size = 16 - pContext->m_BlockOffset;
799         if (copy_size > src_left) {
800             copy_size = src_left;
801         }
802         FXSYS_memcpy32(pContext->m_Block + pContext->m_BlockOffset, src_buf + src_off, copy_size);
803         src_off += copy_size;
804         src_left -= copy_size;
805         pContext->m_BlockOffset += copy_size;
806         if (pContext->m_BlockOffset == 16) {
807             if (!bEncrypt && pContext->m_bIV) {
808                 CRYPT_AESSetIV(pContext->m_Context, pContext->m_Block);
809                 pContext->m_bIV = FALSE;
810                 pContext->m_BlockOffset = 0;
811             } else if (src_off < src_size) {
812                 FX_BYTE block_buf[16];
813                 if (bEncrypt) {
814                     CRYPT_AESEncrypt(pContext->m_Context, block_buf, pContext->m_Block, 16);
815                 } else {
816                     CRYPT_AESDecrypt(pContext->m_Context, block_buf, pContext->m_Block, 16);
817                 }
818                 dest_buf.AppendBlock(block_buf, 16);
819                 pContext->m_BlockOffset = 0;
820             }
821         }
822         if (!src_left) {
823             break;
824         }
825     }
826     return TRUE;
827 }
CryptFinish(FX_LPVOID context,CFX_BinaryBuf & dest_buf,FX_BOOL bEncrypt)828 FX_BOOL CPDF_StandardCryptoHandler::CryptFinish(FX_LPVOID context, CFX_BinaryBuf& dest_buf, FX_BOOL bEncrypt)
829 {
830     if (!context) {
831         return FALSE;
832     }
833     if (m_Cipher == FXCIPHER_NONE) {
834         return TRUE;
835     }
836     if (m_Cipher == FXCIPHER_RC4) {
837         FX_Free(context);
838         return TRUE;
839     }
840     AESCryptContext* pContext = (AESCryptContext*)context;
841     if (bEncrypt) {
842         FX_BYTE block_buf[16];
843         if (pContext->m_BlockOffset == 16) {
844             CRYPT_AESEncrypt(pContext->m_Context, block_buf, pContext->m_Block, 16);
845             dest_buf.AppendBlock(block_buf, 16);
846             pContext->m_BlockOffset = 0;
847         }
848         FXSYS_memset8(pContext->m_Block + pContext->m_BlockOffset, (FX_BYTE)(16 - pContext->m_BlockOffset), 16 - pContext->m_BlockOffset);
849         CRYPT_AESEncrypt(pContext->m_Context, block_buf, pContext->m_Block, 16);
850         dest_buf.AppendBlock(block_buf, 16);
851     } else if (pContext->m_BlockOffset == 16) {
852         FX_BYTE block_buf[16];
853         CRYPT_AESDecrypt(pContext->m_Context, block_buf, pContext->m_Block, 16);
854         if (block_buf[15] <= 16) {
855             dest_buf.AppendBlock(block_buf, 16 - block_buf[15]);
856         }
857     }
858     FX_Free(pContext);
859     return TRUE;
860 }
DecryptStart(FX_DWORD objnum,FX_DWORD gennum)861 FX_LPVOID CPDF_StandardCryptoHandler::DecryptStart(FX_DWORD objnum, FX_DWORD gennum)
862 {
863     return CryptStart(objnum, gennum, FALSE);
864 }
DecryptGetSize(FX_DWORD src_size)865 FX_DWORD CPDF_StandardCryptoHandler::DecryptGetSize(FX_DWORD src_size)
866 {
867     return m_Cipher == FXCIPHER_AES ? src_size - 16 : src_size;
868 }
Init(CPDF_Dictionary * pEncryptDict,CPDF_SecurityHandler * pSecurityHandler)869 FX_BOOL CPDF_StandardCryptoHandler::Init(CPDF_Dictionary* pEncryptDict, CPDF_SecurityHandler* pSecurityHandler)
870 {
871     FX_LPCBYTE key;
872     if (!pSecurityHandler->GetCryptInfo(m_Cipher, key, m_KeyLen)) {
873         return FALSE;
874     }
875     if (m_KeyLen > 32 || m_KeyLen < 0) {
876         return FALSE;
877     }
878     if (m_Cipher != FXCIPHER_NONE) {
879         FXSYS_memcpy32(m_EncryptKey, key, m_KeyLen);
880     }
881     if (m_Cipher == FXCIPHER_AES) {
882         m_pAESContext = FX_Alloc(FX_BYTE, 2048);
883     }
884     return TRUE;
885 }
Init(int cipher,FX_LPCBYTE key,int keylen)886 FX_BOOL CPDF_StandardCryptoHandler::Init(int cipher, FX_LPCBYTE key, int keylen)
887 {
888     if (cipher == FXCIPHER_AES) {
889         switch(keylen) {
890             case 16:
891             case 24:
892             case 32:
893                 break;
894             default:
895                 return FALSE;
896         }
897     } else if (cipher == FXCIPHER_AES2) {
898         if (keylen != 32) {
899             return FALSE;
900         }
901     } else if (cipher == FXCIPHER_RC4) {
902         if (keylen < 5 || keylen > 16) {
903             return FALSE;
904         }
905     } else {
906         if (keylen > 32) {
907             keylen = 32;
908         }
909     }
910     m_Cipher = cipher;
911     m_KeyLen = keylen;
912     FXSYS_memcpy32(m_EncryptKey, key, keylen);
913     if (m_Cipher == FXCIPHER_AES) {
914         m_pAESContext = FX_Alloc(FX_BYTE, 2048);
915     }
916     return TRUE;
917 }
DecryptStream(FX_LPVOID context,FX_LPCBYTE src_buf,FX_DWORD src_size,CFX_BinaryBuf & dest_buf)918 FX_BOOL CPDF_StandardCryptoHandler::DecryptStream(FX_LPVOID context, FX_LPCBYTE src_buf, FX_DWORD src_size,
919         CFX_BinaryBuf& dest_buf)
920 {
921     return CryptStream(context, src_buf, src_size, dest_buf, FALSE);
922 }
DecryptFinish(FX_LPVOID context,CFX_BinaryBuf & dest_buf)923 FX_BOOL CPDF_StandardCryptoHandler::DecryptFinish(FX_LPVOID context, CFX_BinaryBuf& dest_buf)
924 {
925     return CryptFinish(context, dest_buf, FALSE);
926 }
EncryptGetSize(FX_DWORD objnum,FX_DWORD version,FX_LPCBYTE src_buf,FX_DWORD src_size)927 FX_DWORD CPDF_StandardCryptoHandler::EncryptGetSize(FX_DWORD objnum, FX_DWORD version, FX_LPCBYTE src_buf, FX_DWORD src_size)
928 {
929     if (m_Cipher == FXCIPHER_AES) {
930         return src_size + 32;
931     }
932     return src_size;
933 }
EncryptContent(FX_DWORD objnum,FX_DWORD gennum,FX_LPCBYTE src_buf,FX_DWORD src_size,FX_LPBYTE dest_buf,FX_DWORD & dest_size)934 FX_BOOL CPDF_StandardCryptoHandler::EncryptContent(FX_DWORD objnum, FX_DWORD gennum, FX_LPCBYTE src_buf, FX_DWORD src_size,
935         FX_LPBYTE dest_buf, FX_DWORD& dest_size)
936 {
937     CryptBlock(TRUE, objnum, gennum, src_buf, src_size, dest_buf, dest_size);
938     return TRUE;
939 }
Decrypt(FX_DWORD objnum,FX_DWORD gennum,CFX_ByteString & str)940 void CPDF_CryptoHandler::Decrypt(FX_DWORD objnum, FX_DWORD gennum, CFX_ByteString& str)
941 {
942     CFX_BinaryBuf dest_buf;
943     FX_LPVOID context = DecryptStart(objnum, gennum);
944     DecryptStream(context, (FX_LPCBYTE)str, str.GetLength(), dest_buf);
945     DecryptFinish(context, dest_buf);
946     str = dest_buf;
947 }
CPDF_StandardCryptoHandler()948 CPDF_StandardCryptoHandler::CPDF_StandardCryptoHandler()
949 {
950     m_pAESContext = NULL;
951     m_Cipher = FXCIPHER_NONE;
952     m_KeyLen = 0;
953 }
~CPDF_StandardCryptoHandler()954 CPDF_StandardCryptoHandler::~CPDF_StandardCryptoHandler()
955 {
956     if (m_pAESContext) {
957         FX_Free(m_pAESContext);
958     }
959 }
960