1 #define NROUNDS 32
2
3 #define substLong(t) ( (uint)SubstTable20[(uint)t&255] | \
4 ((uint)SubstTable20[(int)(t>> 8)&255]<< 8) | \
5 ((uint)SubstTable20[(int)(t>>16)&255]<<16) | \
6 ((uint)SubstTable20[(int)(t>>24)&255]<<24) )
7
8
9 static byte InitSubstTable20[256]={
10 215, 19,149, 35, 73,197,192,205,249, 28, 16,119, 48,221, 2, 42,
11 232, 1,177,233, 14, 88,219, 25,223,195,244, 90, 87,239,153,137,
12 255,199,147, 70, 92, 66,246, 13,216, 40, 62, 29,217,230, 86, 6,
13 71, 24,171,196,101,113,218,123, 93, 91,163,178,202, 67, 44,235,
14 107,250, 75,234, 49,167,125,211, 83,114,157,144, 32,193,143, 36,
15 158,124,247,187, 89,214,141, 47,121,228, 61,130,213,194,174,251,
16 97,110, 54,229,115, 57,152, 94,105,243,212, 55,209,245, 63, 11,
17 164,200, 31,156, 81,176,227, 21, 76, 99,139,188,127, 17,248, 51,
18 207,120,189,210, 8,226, 41, 72,183,203,135,165,166, 60, 98, 7,
19 122, 38,155,170, 69,172,252,238, 39,134, 59,128,236, 27,240, 80,
20 131, 3, 85,206,145, 79,154,142,159,220,201,133, 74, 64, 20,129,
21 224,185,138,103,173,182, 43, 34,254, 82,198,151,231,180, 58, 10,
22 118, 26,102, 12, 50,132, 22,191,136,111,162,179, 45, 4,148,108,
23 161, 56, 78,126,242,222, 15,175,146, 23, 33,241,181,190, 77,225,
24 0, 46,169,186, 68, 95,237, 65, 53,208,253,168, 9, 18,100, 52,
25 116,184,160, 96,109, 37, 30,106,140,104,150, 5,204,117,112, 84
26 };
27
28
SetKey20(const char * Password)29 void CryptData::SetKey20(const char *Password)
30 {
31 InitCRC32(CRCTab);
32
33 char Psw[MAXPASSWORD];
34 strncpyz(Psw,Password,ASIZE(Psw)); // We'll need to modify it below.
35 size_t PswLength=strlen(Psw);
36
37 Key20[0]=0xD3A3B879L;
38 Key20[1]=0x3F6D12F7L;
39 Key20[2]=0x7515A235L;
40 Key20[3]=0xA4E7F123L;
41
42 memcpy(SubstTable20,InitSubstTable20,sizeof(SubstTable20));
43 for (uint J=0;J<256;J++)
44 for (size_t I=0;I<PswLength;I+=2)
45 {
46 uint N1=(byte)CRCTab [ (byte(Password[I]) - J) &0xff];
47 uint N2=(byte)CRCTab [ (byte(Password[I+1]) + J) &0xff];
48 for (int K=1;N1!=N2;N1=(N1+1)&0xff,K++)
49 Swap20(&SubstTable20[N1],&SubstTable20[(N1+I+K)&0xff]);
50 }
51
52 // Incomplete last block of password must be zero padded.
53 if ((PswLength & CRYPT_BLOCK_MASK)!=0)
54 for (size_t I=PswLength;I<=(PswLength|CRYPT_BLOCK_MASK);I++)
55 Psw[I]=0;
56
57 for (size_t I=0;I<PswLength;I+=CRYPT_BLOCK_SIZE)
58 EncryptBlock20((byte *)Psw+I);
59 }
60
61
EncryptBlock20(byte * Buf)62 void CryptData::EncryptBlock20(byte *Buf)
63 {
64 uint A,B,C,D,T,TA,TB;
65 A=RawGet4(Buf+0)^Key20[0];
66 B=RawGet4(Buf+4)^Key20[1];
67 C=RawGet4(Buf+8)^Key20[2];
68 D=RawGet4(Buf+12)^Key20[3];
69 for(int I=0;I<NROUNDS;I++)
70 {
71 T=((C+rotls(D,11,32))^Key20[I&3]);
72 TA=A^substLong(T);
73 T=((D^rotls(C,17,32))+Key20[I&3]);
74 TB=B^substLong(T);
75 A=C;
76 B=D;
77 C=TA;
78 D=TB;
79 }
80 RawPut4(C^Key20[0],Buf+0);
81 RawPut4(D^Key20[1],Buf+4);
82 RawPut4(A^Key20[2],Buf+8);
83 RawPut4(B^Key20[3],Buf+12);
84 UpdKeys20(Buf);
85 }
86
87
DecryptBlock20(byte * Buf)88 void CryptData::DecryptBlock20(byte *Buf)
89 {
90 byte InBuf[16];
91 uint A,B,C,D,T,TA,TB;
92 A=RawGet4(Buf+0)^Key20[0];
93 B=RawGet4(Buf+4)^Key20[1];
94 C=RawGet4(Buf+8)^Key20[2];
95 D=RawGet4(Buf+12)^Key20[3];
96 memcpy(InBuf,Buf,sizeof(InBuf));
97 for(int I=NROUNDS-1;I>=0;I--)
98 {
99 T=((C+rotls(D,11,32))^Key20[I&3]);
100 TA=A^substLong(T);
101 T=((D^rotls(C,17,32))+Key20[I&3]);
102 TB=B^substLong(T);
103 A=C;
104 B=D;
105 C=TA;
106 D=TB;
107 }
108 RawPut4(C^Key20[0],Buf+0);
109 RawPut4(D^Key20[1],Buf+4);
110 RawPut4(A^Key20[2],Buf+8);
111 RawPut4(B^Key20[3],Buf+12);
112 UpdKeys20(InBuf);
113 }
114
115
UpdKeys20(byte * Buf)116 void CryptData::UpdKeys20(byte *Buf)
117 {
118 for (int I=0;I<16;I+=4)
119 {
120 Key20[0]^=CRCTab[Buf[I]];
121 Key20[1]^=CRCTab[Buf[I+1]];
122 Key20[2]^=CRCTab[Buf[I+2]];
123 Key20[3]^=CRCTab[Buf[I+3]];
124 }
125 }
126
127
Swap20(byte * Ch1,byte * Ch2)128 void CryptData::Swap20(byte *Ch1,byte *Ch2)
129 {
130 byte Ch=*Ch1;
131 *Ch1=*Ch2;
132 *Ch2=Ch;
133 }
134