1 // pkcspad.cpp - originally written and placed in the public domain by Wei Dai
2
3 #include "pch.h"
4
5 #ifndef CRYPTOPP_PKCSPAD_CPP // SunCC workaround: compiler could cause this file to be included twice
6 #define CRYPTOPP_PKCSPAD_CPP
7
8 #include "pkcspad.h"
9 #include "emsa2.h"
10 #include "hashfwd.h"
11 #include "misc.h"
12 #include "trap.h"
13
14 NAMESPACE_BEGIN(CryptoPP)
15
16 // Typedef/cast change due to Clang, http://github.com/weidai11/cryptopp/issues/300
17 template<> const byte PKCS_DigestDecoration<Weak1::MD2>::decoration[] = {0x30,0x20,0x30,0x0c,0x06,0x08,0x2a,0x86,0x48,0x86,0xf7,0x0d,0x02,0x02,0x05,0x00,0x04,0x10};
18 template<> const unsigned int PKCS_DigestDecoration<Weak1::MD2>::length = (unsigned int)sizeof(PKCS_DigestDecoration<Weak1::MD2>::decoration);
19
20 template<> const byte PKCS_DigestDecoration<Weak1::MD5>::decoration[] = {0x30,0x20,0x30,0x0c,0x06,0x08,0x2a,0x86,0x48,0x86,0xf7,0x0d,0x02,0x05,0x05,0x00,0x04,0x10};
21 template<> const unsigned int PKCS_DigestDecoration<Weak1::MD5>::length = (unsigned int)sizeof(PKCS_DigestDecoration<Weak1::MD5>::decoration);
22
23 template<> const byte PKCS_DigestDecoration<RIPEMD160>::decoration[] = {0x30,0x21,0x30,0x09,0x06,0x05,0x2b,0x24,0x03,0x02,0x01,0x05,0x00,0x04,0x14};
24 template<> const unsigned int PKCS_DigestDecoration<RIPEMD160>::length = (unsigned int)sizeof(PKCS_DigestDecoration<RIPEMD160>::decoration);
25
26 template<> const byte PKCS_DigestDecoration<Tiger>::decoration[] = {0x30,0x29,0x30,0x0D,0x06,0x09,0x2B,0x06,0x01,0x04,0x01,0xDA,0x47,0x0C,0x02,0x05,0x00,0x04,0x18};
27 template<> const unsigned int PKCS_DigestDecoration<Tiger>::length = (unsigned int)sizeof(PKCS_DigestDecoration<Tiger>::decoration);
28
29 // Inclusion based on DLL due to Clang, http://github.com/weidai11/cryptopp/issues/300
30 #ifndef CRYPTOPP_IS_DLL
31 template<> const byte PKCS_DigestDecoration<SHA1>::decoration[] = {0x30,0x21,0x30,0x09,0x06,0x05,0x2B,0x0E,0x03,0x02,0x1A,0x05,0x00,0x04,0x14};
32 template<> const unsigned int PKCS_DigestDecoration<SHA1>::length = (unsigned int)sizeof(PKCS_DigestDecoration<SHA1>::decoration);
33
34 template<> const byte PKCS_DigestDecoration<SHA224>::decoration[] = {0x30,0x2d,0x30,0x0d,0x06,0x09,0x60,0x86,0x48,0x01,0x65,0x03,0x04,0x02,0x04,0x05,0x00,0x04,0x1c};
35 template<> const unsigned int PKCS_DigestDecoration<SHA224>::length = (unsigned int)sizeof(PKCS_DigestDecoration<SHA224>::decoration);
36
37 template<> const byte PKCS_DigestDecoration<SHA256>::decoration[] = {0x30,0x31,0x30,0x0d,0x06,0x09,0x60,0x86,0x48,0x01,0x65,0x03,0x04,0x02,0x01,0x05,0x00,0x04,0x20};
38 template<> const unsigned int PKCS_DigestDecoration<SHA256>::length = (unsigned int)sizeof(PKCS_DigestDecoration<SHA256>::decoration);
39
40 template<> const byte PKCS_DigestDecoration<SHA384>::decoration[] = {0x30,0x41,0x30,0x0d,0x06,0x09,0x60,0x86,0x48,0x01,0x65,0x03,0x04,0x02,0x02,0x05,0x00,0x04,0x30};
41 template<> const unsigned int PKCS_DigestDecoration<SHA384>::length = (unsigned int)sizeof(PKCS_DigestDecoration<SHA384>::decoration);
42
43 template<> const byte PKCS_DigestDecoration<SHA512>::decoration[] = {0x30,0x51,0x30,0x0d, 0x06,0x09,0x60,0x86, 0x48,0x01,0x65,0x03, 0x04,0x02,0x03,0x05, 0x00,0x04,0x40};
44 template<> const unsigned int PKCS_DigestDecoration<SHA512>::length = (unsigned int)sizeof(PKCS_DigestDecoration<SHA512>::decoration);
45
46 // http://github.com/weidai11/cryptopp/issues/517. OIDs and encoded prefixes found at
47 // http://www.ietf.org/archive/id/draft-jivsov-openpgp-sha3-01.txt
48 template<> const byte PKCS_DigestDecoration<SHA3_256>::decoration[] = {0x30,0x31,0x30,0x0d, 0x06,0x09,0x60,0x86, 0x48,0x01,0x65,0x03, 0x04,0x02,0x08,0x05, 0x00,0x04,0x20};
49 template<> const unsigned int PKCS_DigestDecoration<SHA3_256>::length = (unsigned int)sizeof(PKCS_DigestDecoration<SHA3_256>::decoration);
50
51 template<> const byte PKCS_DigestDecoration<SHA3_384>::decoration[] = {0x30,0x41,0x30,0x0d, 0x06,0x09,0x60,0x86, 0x48,0x01,0x65,0x03, 0x04,0x02,0x09,0x05, 0x00,0x04,0x30};
52 template<> const unsigned int PKCS_DigestDecoration<SHA3_384>::length = (unsigned int)sizeof(PKCS_DigestDecoration<SHA3_384>::decoration);
53
54 template<> const byte PKCS_DigestDecoration<SHA3_512>::decoration[] = {0x30,0x51,0x30,0x0d, 0x06,0x09,0x60,0x86, 0x48,0x01,0x65,0x03, 0x04,0x02,0x0a,0x05, 0x00,0x04,0x40};
55 template<> const unsigned int PKCS_DigestDecoration<SHA3_512>::length = (unsigned int)sizeof(PKCS_DigestDecoration<SHA3_512>::decoration);
56 #endif
57
MaxUnpaddedLength(size_t paddedLength) const58 size_t PKCS_EncryptionPaddingScheme::MaxUnpaddedLength(size_t paddedLength) const
59 {
60 return SaturatingSubtract(paddedLength/8, 10U);
61 }
62
Pad(RandomNumberGenerator & rng,const byte * input,size_t inputLen,byte * pkcsBlock,size_t pkcsBlockLen,const NameValuePairs & parameters) const63 void PKCS_EncryptionPaddingScheme::Pad(RandomNumberGenerator& rng, const byte *input, size_t inputLen, byte *pkcsBlock, size_t pkcsBlockLen, const NameValuePairs& parameters) const
64 {
65 CRYPTOPP_UNUSED(parameters);
66 CRYPTOPP_ASSERT (inputLen <= MaxUnpaddedLength(pkcsBlockLen)); // this should be checked by caller
67
68 // convert from bit length to byte length
69 if (pkcsBlockLen % 8 != 0)
70 {
71 pkcsBlock[0] = 0;
72 pkcsBlock++;
73 }
74 pkcsBlockLen /= 8;
75
76 pkcsBlock[0] = 2; // block type 2
77
78 // pad with non-zero random bytes
79 for (unsigned i = 1; i < pkcsBlockLen-inputLen-1; i++)
80 pkcsBlock[i] = (byte)rng.GenerateWord32(1, 0xff);
81
82 pkcsBlock[pkcsBlockLen-inputLen-1] = 0; // separator
83 memcpy(pkcsBlock+pkcsBlockLen-inputLen, input, inputLen);
84 }
85
Unpad(const byte * pkcsBlock,size_t pkcsBlockLen,byte * output,const NameValuePairs & parameters) const86 DecodingResult PKCS_EncryptionPaddingScheme::Unpad(const byte *pkcsBlock, size_t pkcsBlockLen, byte *output, const NameValuePairs& parameters) const
87 {
88 CRYPTOPP_UNUSED(parameters);
89 bool invalid = false;
90 size_t maxOutputLen = MaxUnpaddedLength(pkcsBlockLen);
91
92 // convert from bit length to byte length
93 if (pkcsBlockLen % 8 != 0)
94 {
95 invalid = (pkcsBlock[0] != 0) || invalid;
96 pkcsBlock++;
97 }
98 pkcsBlockLen /= 8;
99
100 // Require block type 2.
101 invalid = (pkcsBlock[0] != 2) || invalid;
102
103 // skip past the padding until we find the separator
104 size_t i=1;
105 while (i<pkcsBlockLen && pkcsBlock[i++]) { // null body
106 }
107 CRYPTOPP_ASSERT(i==pkcsBlockLen || pkcsBlock[i-1]==0);
108
109 size_t outputLen = pkcsBlockLen - i;
110 invalid = (outputLen > maxOutputLen) || invalid;
111
112 if (invalid)
113 return DecodingResult();
114
115 memcpy (output, pkcsBlock+i, outputLen);
116 return DecodingResult(outputLen);
117 }
118
119 // ********************************************************
120
121 #ifndef CRYPTOPP_IMPORTS
122
ComputeMessageRepresentative(RandomNumberGenerator & rng,const byte * recoverableMessage,size_t recoverableMessageLength,HashTransformation & hash,HashIdentifier hashIdentifier,bool messageEmpty,byte * representative,size_t representativeBitLength) const123 void PKCS1v15_SignatureMessageEncodingMethod::ComputeMessageRepresentative(RandomNumberGenerator &rng,
124 const byte *recoverableMessage, size_t recoverableMessageLength,
125 HashTransformation &hash, HashIdentifier hashIdentifier, bool messageEmpty,
126 byte *representative, size_t representativeBitLength) const
127 {
128 CRYPTOPP_UNUSED(rng), CRYPTOPP_UNUSED(recoverableMessage), CRYPTOPP_UNUSED(recoverableMessageLength);
129 CRYPTOPP_UNUSED(messageEmpty), CRYPTOPP_UNUSED(hashIdentifier);
130 CRYPTOPP_ASSERT(representativeBitLength >= MinRepresentativeBitLength(hashIdentifier.second, hash.DigestSize()));
131
132 size_t pkcsBlockLen = representativeBitLength;
133 // convert from bit length to byte length
134 if (pkcsBlockLen % 8 != 0)
135 {
136 representative[0] = 0;
137 representative++;
138 }
139 pkcsBlockLen /= 8;
140
141 representative[0] = 1; // block type 1
142
143 unsigned int digestSize = hash.DigestSize();
144 byte *pPadding = representative + 1;
145 byte *pDigest = representative + pkcsBlockLen - digestSize;
146 byte *pHashId = pDigest - hashIdentifier.second;
147 byte *pSeparator = pHashId - 1;
148
149 // pad with 0xff
150 memset(pPadding, 0xff, pSeparator-pPadding);
151 *pSeparator = 0;
152 memcpy(pHashId, hashIdentifier.first, hashIdentifier.second);
153 hash.Final(pDigest);
154 }
155
156 #endif
157
158 NAMESPACE_END
159
160 #endif
161