Annotation of src/usr.bin/ssh/xmss_hash.c, Revision 1.3
1.3 ! millert 1: /* $OpenBSD: xmss_hash.c,v 1.2 2018/02/26 03:56:44 dtucker Exp $ */
1.1 markus 2: /*
3: hash.c version 20160722
4: Andreas Hülsing
5: Joost Rijneveld
6: Public domain.
7: */
8:
9: #include "xmss_hash_address.h"
10: #include "xmss_commons.h"
11: #include "xmss_hash.h"
12:
13: #include <stddef.h>
14: #include <stdint.h>
15: #include <stdio.h>
16: #include <string.h>
17: #include <openssl/sha.h>
18:
19: int core_hash_SHA2(unsigned char *, const unsigned int, const unsigned char *,
20: unsigned int, const unsigned char *, unsigned long long, unsigned int);
21:
22: unsigned char* addr_to_byte(unsigned char *bytes, const uint32_t addr[8]){
23: #if IS_LITTLE_ENDIAN==1
24: int i = 0;
25: for(i=0;i<8;i++)
26: to_byte(bytes+i*4, addr[i],4);
27: return bytes;
28: #else
29: memcpy(bytes, addr, 32);
30: return bytes;
31: #endif
32: }
33:
34: int core_hash_SHA2(unsigned char *out, const unsigned int type, const unsigned char *key, unsigned int keylen, const unsigned char *in, unsigned long long inlen, unsigned int n){
35: unsigned long long i = 0;
36: unsigned char buf[inlen + n + keylen];
37:
38: // Input is (toByte(X, 32) || KEY || M)
39:
40: // set toByte
41: to_byte(buf, type, n);
42:
43: for (i=0; i < keylen; i++) {
44: buf[i+n] = key[i];
45: }
46:
47: for (i=0; i < inlen; i++) {
48: buf[keylen + n + i] = in[i];
49: }
50:
51: if (n == 32) {
52: SHA256(buf, inlen + keylen + n, out);
53: return 0;
54: }
55: else {
56: if (n == 64) {
57: SHA512(buf, inlen + keylen + n, out);
58: return 0;
59: }
60: }
61: return 1;
62: }
63:
64: /**
65: * Implements PRF
66: */
67: int prf(unsigned char *out, const unsigned char *in, const unsigned char *key, unsigned int keylen)
68: {
69: return core_hash_SHA2(out, 3, key, keylen, in, 32, keylen);
70: }
71:
72: /*
73: * Implemts H_msg
74: */
75: int h_msg(unsigned char *out, const unsigned char *in, unsigned long long inlen, const unsigned char *key, const unsigned int keylen, const unsigned int n)
76: {
77: if (keylen != 3*n){
78: // H_msg takes 3n-bit keys, but n does not match the keylength of keylen
79: return -1;
80: }
81: return core_hash_SHA2(out, 2, key, keylen, in, inlen, n);
82: }
83:
84: /**
85: * We assume the left half is in in[0]...in[n-1]
86: */
87: int hash_h(unsigned char *out, const unsigned char *in, const unsigned char *pub_seed, uint32_t addr[8], const unsigned int n)
88: {
89:
90: unsigned char buf[2*n];
91: unsigned char key[n];
92: unsigned char bitmask[2*n];
93: unsigned char byte_addr[32];
94: unsigned int i;
95:
96: setKeyAndMask(addr, 0);
97: addr_to_byte(byte_addr, addr);
98: prf(key, byte_addr, pub_seed, n);
99: // Use MSB order
100: setKeyAndMask(addr, 1);
101: addr_to_byte(byte_addr, addr);
102: prf(bitmask, byte_addr, pub_seed, n);
103: setKeyAndMask(addr, 2);
104: addr_to_byte(byte_addr, addr);
105: prf(bitmask+n, byte_addr, pub_seed, n);
106: for (i = 0; i < 2*n; i++) {
107: buf[i] = in[i] ^ bitmask[i];
108: }
109: return core_hash_SHA2(out, 1, key, n, buf, 2*n, n);
110: }
111:
112: int hash_f(unsigned char *out, const unsigned char *in, const unsigned char *pub_seed, uint32_t addr[8], const unsigned int n)
113: {
114: unsigned char buf[n];
115: unsigned char key[n];
116: unsigned char bitmask[n];
117: unsigned char byte_addr[32];
118: unsigned int i;
119:
120: setKeyAndMask(addr, 0);
121: addr_to_byte(byte_addr, addr);
122: prf(key, byte_addr, pub_seed, n);
123:
124: setKeyAndMask(addr, 1);
125: addr_to_byte(byte_addr, addr);
126: prf(bitmask, byte_addr, pub_seed, n);
127:
128: for (i = 0; i < n; i++) {
129: buf[i] = in[i] ^ bitmask[i];
130: }
131: return core_hash_SHA2(out, 0, key, n, buf, n, n);
132: }