|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
|
// dsa.cpp - written and placed in the public domain by Wei Dai
#include "pch.h"
#ifndef CRYPTOPP_IMPORTS
#include "dsa.h"
#include "nbtheory.h"
NAMESPACE_BEGIN(CryptoPP)
size_t DSAConvertSignatureFormat(byte *buffer, size_t bufferSize, DSASignatureFormat toFormat, const byte *signature, size_t signatureLen, DSASignatureFormat fromFormat)
{
Integer r, s;
StringStore store(signature, signatureLen);
ArraySink sink(buffer, bufferSize);
switch (fromFormat)
{
case DSA_P1363:
r.Decode(store, signatureLen/2);
s.Decode(store, signatureLen/2);
break;
case DSA_DER:
{
BERSequenceDecoder seq(store);
r.BERDecode(seq);
s.BERDecode(seq);
seq.MessageEnd();
break;
}
case DSA_OPENPGP:
r.OpenPGPDecode(store);
s.OpenPGPDecode(store);
break;
}
switch (toFormat)
{
case DSA_P1363:
r.Encode(sink, bufferSize/2);
s.Encode(sink, bufferSize/2);
break;
case DSA_DER:
{
DERSequenceEncoder seq(sink);
r.DEREncode(seq);
s.DEREncode(seq);
seq.MessageEnd();
break;
}
case DSA_OPENPGP:
r.OpenPGPEncode(sink);
s.OpenPGPEncode(sink);
break;
}
return (size_t)sink.TotalPutLength();
}
NAMESPACE_END
#endif
|