xref: /plan9/sys/src/libsec/port/sha2_128.c (revision 7bc319fb0923feebf3ecec8ba4171959fa2265e2)
1 /*
2  * sha2 128-bit
3  */
4 #include <u.h>
5 #include <libc.h>
6 #include <libsec.h>
7 
8 static void encode64(uchar*, u64int*, ulong);
9 static DigestState* sha2_128(uchar *, ulong, uchar *, SHA2_256state *, int);
10 
11 extern void _sha2block128(uchar*, ulong, u64int*);
12 
13 /*
14  *  for sha2_384 and sha2_512, len must be multiple of 128 for all but
15  *  the last call.  There must be room in the input buffer to pad.
16  *
17  *  Note: sha2_384 calls sha2_512block as sha2_384; it just uses a different
18  *  initial seed to produce a truncated 384b hash result.  otherwise
19  *  it's the same as sha2_512.
20  */
21 SHA2_384state*
sha2_384(uchar * p,ulong len,uchar * digest,SHA2_384state * s)22 sha2_384(uchar *p, ulong len, uchar *digest, SHA2_384state *s)
23 {
24 	if(s == nil) {
25 		s = mallocz(sizeof(*s), 1);
26 		if(s == nil)
27 			return nil;
28 		s->malloced = 1;
29 	}
30 	if(s->seeded == 0){
31 		/*
32 		 * seed the state with the first 64 bits of the fractional
33 		 * parts of the square roots of the 9th thru 16th primes.
34 		 */
35  		s->bstate[0] = 0xcbbb9d5dc1059ed8LL;
36 		s->bstate[1] = 0x629a292a367cd507LL;
37 		s->bstate[2] = 0x9159015a3070dd17LL;
38 		s->bstate[3] = 0x152fecd8f70e5939LL;
39 		s->bstate[4] = 0x67332667ffc00b31LL;
40 		s->bstate[5] = 0x8eb44a8768581511LL;
41 		s->bstate[6] = 0xdb0c2e0d64f98fa7LL;
42 		s->bstate[7] = 0x47b5481dbefa4fa4LL;
43 		s->seeded = 1;
44 	}
45 	return sha2_128(p, len, digest, s, SHA2_384dlen);
46 }
47 
48 SHA2_512state*
sha2_512(uchar * p,ulong len,uchar * digest,SHA2_512state * s)49 sha2_512(uchar *p, ulong len, uchar *digest, SHA2_512state *s)
50 {
51 
52 	if(s == nil) {
53 		s = mallocz(sizeof(*s), 1);
54 		if(s == nil)
55 			return nil;
56 		s->malloced = 1;
57 	}
58 	if(s->seeded == 0){
59 		/*
60 		 * seed the state with the first 64 bits of the fractional
61 		 * parts of the square roots of the first 8 primes 2..19).
62 		 */
63  		s->bstate[0] = 0x6a09e667f3bcc908LL;
64 		s->bstate[1] = 0xbb67ae8584caa73bLL;
65 		s->bstate[2] = 0x3c6ef372fe94f82bLL;
66 		s->bstate[3] = 0xa54ff53a5f1d36f1LL;
67 		s->bstate[4] = 0x510e527fade682d1LL;
68 		s->bstate[5] = 0x9b05688c2b3e6c1fLL;
69 		s->bstate[6] = 0x1f83d9abfb41bd6bLL;
70 		s->bstate[7] = 0x5be0cd19137e2179LL;
71 		s->seeded = 1;
72 	}
73 	return sha2_128(p, len, digest, s, SHA2_512dlen);
74 }
75 
76 /* common 128 byte block padding and count code for SHA2_384 and SHA2_512 */
77 static DigestState*
sha2_128(uchar * p,ulong len,uchar * digest,SHA2_512state * s,int dlen)78 sha2_128(uchar *p, ulong len, uchar *digest, SHA2_512state *s, int dlen)
79 {
80 	int i;
81 	u64int x[16];
82 	uchar buf[256];
83 	uchar *e;
84 
85 	/* fill out the partial 128 byte block from previous calls */
86 	if(s->blen){
87 		i = 128 - s->blen;
88 		if(len < i)
89 			i = len;
90 		memmove(s->buf + s->blen, p, i);
91 		len -= i;
92 		s->blen += i;
93 		p += i;
94 		if(s->blen == 128){
95 			_sha2block128(s->buf, s->blen, s->bstate);
96 			s->len += s->blen;
97 			s->blen = 0;
98 		}
99 	}
100 
101 	/* do 128 byte blocks */
102 	i = len & ~(128-1);
103 	if(i){
104 		_sha2block128(p, i, s->bstate);
105 		s->len += i;
106 		len -= i;
107 		p += i;
108 	}
109 
110 	/* save the left overs if not last call */
111 	if(digest == 0){
112 		if(len){
113 			memmove(s->buf, p, len);
114 			s->blen += len;
115 		}
116 		return s;
117 	}
118 
119 	/*
120 	 *  this is the last time through, pad what's left with 0x80,
121 	 *  0's, and the input count to create a multiple of 128 bytes.
122 	 */
123 	if(s->blen){
124 		p = s->buf;
125 		len = s->blen;
126 	} else {
127 		memmove(buf, p, len);
128 		p = buf;
129 	}
130 	s->len += len;
131 	e = p + len;
132 	if(len < 112)
133 		i = 112 - len;
134 	else
135 		i = 240 - len;
136 	memset(e, 0, i);
137 	*e = 0x80;
138 	len += i;
139 
140 	/* append the count */
141 	x[0] = 0;			/* assume 32b length, i.e. < 4GB */
142 	x[1] = s->len<<3;
143 	encode64(p+len, x, 16);
144 
145 	/* digest the last part */
146 	_sha2block128(p, len+16, s->bstate);
147 	s->len += len+16;
148 
149 	/* return result and free state */
150 	encode64(digest, s->bstate, dlen);
151 	if(s->malloced == 1)
152 		free(s);
153 	return nil;
154 }
155 
156 /*
157  * Encodes input (ulong long) into output (uchar).
158  * Assumes len is a multiple of 8.
159  */
160 static void
encode64(uchar * output,u64int * input,ulong len)161 encode64(uchar *output, u64int *input, ulong len)
162 {
163 	u64int x;
164 	uchar *e;
165 
166 	for(e = output + len; output < e;) {
167 		x = *input++;
168 		*output++ = x >> 56;
169 		*output++ = x >> 48;
170 		*output++ = x >> 40;
171 		*output++ = x >> 32;
172 		*output++ = x >> 24;
173 		*output++ = x >> 16;
174 		*output++ = x >> 8;
175 		*output++ = x;
176 	}
177 }
178 
179 DigestState*
hmac_sha2_384(uchar * p,ulong len,uchar * key,ulong klen,uchar * digest,DigestState * s)180 hmac_sha2_384(uchar *p, ulong len, uchar *key, ulong klen, uchar *digest,
181 	DigestState *s)
182 {
183 	return hmac_x(p, len, key, klen, digest, s, sha2_384, SHA2_384dlen);
184 }
185 
186 DigestState*
hmac_sha2_512(uchar * p,ulong len,uchar * key,ulong klen,uchar * digest,DigestState * s)187 hmac_sha2_512(uchar *p, ulong len, uchar *key, ulong klen, uchar *digest,
188 	DigestState *s)
189 {
190 	return hmac_x(p, len, key, klen, digest, s, sha2_512, SHA2_512dlen);
191 }
192