4 * Arne de Bruijn (arne@knoware.nl), 1997
9 #ifdef CONFIG_NCPFS_PACKET_SIGNING
11 #include <linux/string.h>
12 #include <linux/ncp.h>
13 #include <linux/bitops.h>
14 #include "ncpsign_kernel.h"
16 /* i386: 32-bit, little endian, handles mis-alignment */
18 #define GET_LE32(p) (*(int *)(p))
19 #define PUT_LE32(p,v) { *(int *)(p)=v; }
21 /* from include/ncplib.h */
22 #define BVAL(buf,pos) (((__u8 *)(buf))[pos])
23 #define PVAL(buf,pos) ((unsigned)BVAL(buf,pos))
24 #define BSET(buf,pos,val) (BVAL(buf,pos) = (val))
27 WVAL_LH(__u8 * buf, int pos)
29 return PVAL(buf, pos) | PVAL(buf, pos + 1) << 8;
32 DVAL_LH(__u8 * buf, int pos)
34 return WVAL_LH(buf, pos) | WVAL_LH(buf, pos + 2) << 16;
37 WSET_LH(__u8 * buf, int pos, __u16 val)
39 BSET(buf, pos, val & 0xff);
40 BSET(buf, pos + 1, val >> 8);
43 DSET_LH(__u8 * buf, int pos, __u32 val)
45 WSET_LH(buf, pos, val & 0xffff);
46 WSET_LH(buf, pos + 2, val >> 16);
49 #define GET_LE32(p) DVAL_LH(p,0)
50 #define PUT_LE32(p,v) DSET_LH(p,0,v)
53 static void nwsign(char *r_data1, char *r_data2, char *outdata) {
55 unsigned int w0,w1,w2,w3;
56 static int rbit[4]={0, 2, 1, 3};
58 unsigned int *data2=(unsigned int *)r_data2;
60 unsigned int data2[16];
62 data2[i]=GET_LE32(r_data2+(i<<2));
65 w1=GET_LE32(r_data1+4);
66 w2=GET_LE32(r_data1+8);
67 w3=GET_LE32(r_data1+12);
69 w0=rol32(w0 + ((w1 & w2) | ((~w1) & w3)) + data2[i+0],3);
70 w3=rol32(w3 + ((w0 & w1) | ((~w0) & w2)) + data2[i+1],7);
71 w2=rol32(w2 + ((w3 & w0) | ((~w3) & w1)) + data2[i+2],11);
72 w1=rol32(w1 + ((w2 & w3) | ((~w2) & w0)) + data2[i+3],19);
75 w0=rol32(w0 + (((w2 | w3) & w1) | (w2 & w3)) + 0x5a827999 + data2[i+0],3);
76 w3=rol32(w3 + (((w1 | w2) & w0) | (w1 & w2)) + 0x5a827999 + data2[i+4],5);
77 w2=rol32(w2 + (((w0 | w1) & w3) | (w0 & w1)) + 0x5a827999 + data2[i+8],9);
78 w1=rol32(w1 + (((w3 | w0) & w2) | (w3 & w0)) + 0x5a827999 + data2[i+12],13);
81 w0=rol32(w0 + ((w1 ^ w2) ^ w3) + 0x6ed9eba1 + data2[rbit[i]+0],3);
82 w3=rol32(w3 + ((w0 ^ w1) ^ w2) + 0x6ed9eba1 + data2[rbit[i]+8],9);
83 w2=rol32(w2 + ((w3 ^ w0) ^ w1) + 0x6ed9eba1 + data2[rbit[i]+4],11);
84 w1=rol32(w1 + ((w2 ^ w3) ^ w0) + 0x6ed9eba1 + data2[rbit[i]+12],15);
86 PUT_LE32(outdata,(w0+GET_LE32(r_data1)) & 0xffffffff);
87 PUT_LE32(outdata+4,(w1+GET_LE32(r_data1+4)) & 0xffffffff);
88 PUT_LE32(outdata+8,(w2+GET_LE32(r_data1+8)) & 0xffffffff);
89 PUT_LE32(outdata+12,(w3+GET_LE32(r_data1+12)) & 0xffffffff);
92 /* Make a signature for the current packet and add it at the end of the */
94 void __sign_packet(struct ncp_server *server, const char *packet, size_t size, __u32 totalsize, void *sign_buff) {
95 unsigned char data[64];
97 memcpy(data, server->sign_root, 8);
98 *(__u32*)(data + 8) = totalsize;
100 memcpy(data + 12, packet, size);
101 memset(data + 12 + size, 0, 52 - size);
103 memcpy(data + 12, packet, 52);
105 nwsign(server->sign_last, data, server->sign_last);
106 memcpy(sign_buff, server->sign_last, 8);
109 int sign_verify_reply(struct ncp_server *server, const char *packet, size_t size, __u32 totalsize, const void *sign_buff) {
110 unsigned char data[64];
111 unsigned char hash[16];
113 memcpy(data, server->sign_root, 8);
114 *(__u32*)(data + 8) = totalsize;
116 memcpy(data + 12, packet, size);
117 memset(data + 12 + size, 0, 52 - size);
119 memcpy(data + 12, packet, 52);
121 nwsign(server->sign_last, data, hash);
122 return memcmp(sign_buff, hash, 8);
125 #endif /* CONFIG_NCPFS_PACKET_SIGNING */