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Diffstat (limited to 'poly1305.c')
-rw-r--r-- | poly1305.c | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/poly1305.c b/poly1305.c new file mode 100644 index 000000000..6fd1fc8cd --- /dev/null +++ b/poly1305.c | |||
@@ -0,0 +1,160 @@ | |||
1 | /* | ||
2 | * Public Domain poly1305 from Andrew Moon | ||
3 | * poly1305-donna-unrolled.c from https://github.com/floodyberry/poly1305-donna | ||
4 | */ | ||
5 | |||
6 | /* $OpenBSD: poly1305.c,v 1.3 2013/12/19 22:57:13 djm Exp $ */ | ||
7 | |||
8 | #include "includes.h" | ||
9 | |||
10 | #include <sys/types.h> | ||
11 | #ifdef HAVE_STDINT_H | ||
12 | # include <stdint.h> | ||
13 | #endif | ||
14 | |||
15 | #include "poly1305.h" | ||
16 | |||
17 | #define mul32x32_64(a,b) ((uint64_t)(a) * (b)) | ||
18 | |||
19 | #define U8TO32_LE(p) \ | ||
20 | (((uint32_t)((p)[0])) | \ | ||
21 | ((uint32_t)((p)[1]) << 8) | \ | ||
22 | ((uint32_t)((p)[2]) << 16) | \ | ||
23 | ((uint32_t)((p)[3]) << 24)) | ||
24 | |||
25 | #define U32TO8_LE(p, v) \ | ||
26 | do { \ | ||
27 | (p)[0] = (uint8_t)((v)); \ | ||
28 | (p)[1] = (uint8_t)((v) >> 8); \ | ||
29 | (p)[2] = (uint8_t)((v) >> 16); \ | ||
30 | (p)[3] = (uint8_t)((v) >> 24); \ | ||
31 | } while (0) | ||
32 | |||
33 | void | ||
34 | poly1305_auth(unsigned char out[POLY1305_TAGLEN], const unsigned char *m, size_t inlen, const unsigned char key[POLY1305_KEYLEN]) { | ||
35 | uint32_t t0,t1,t2,t3; | ||
36 | uint32_t h0,h1,h2,h3,h4; | ||
37 | uint32_t r0,r1,r2,r3,r4; | ||
38 | uint32_t s1,s2,s3,s4; | ||
39 | uint32_t b, nb; | ||
40 | size_t j; | ||
41 | uint64_t t[5]; | ||
42 | uint64_t f0,f1,f2,f3; | ||
43 | uint32_t g0,g1,g2,g3,g4; | ||
44 | uint64_t c; | ||
45 | unsigned char mp[16]; | ||
46 | |||
47 | /* clamp key */ | ||
48 | t0 = U8TO32_LE(key+0); | ||
49 | t1 = U8TO32_LE(key+4); | ||
50 | t2 = U8TO32_LE(key+8); | ||
51 | t3 = U8TO32_LE(key+12); | ||
52 | |||
53 | /* precompute multipliers */ | ||
54 | r0 = t0 & 0x3ffffff; t0 >>= 26; t0 |= t1 << 6; | ||
55 | r1 = t0 & 0x3ffff03; t1 >>= 20; t1 |= t2 << 12; | ||
56 | r2 = t1 & 0x3ffc0ff; t2 >>= 14; t2 |= t3 << 18; | ||
57 | r3 = t2 & 0x3f03fff; t3 >>= 8; | ||
58 | r4 = t3 & 0x00fffff; | ||
59 | |||
60 | s1 = r1 * 5; | ||
61 | s2 = r2 * 5; | ||
62 | s3 = r3 * 5; | ||
63 | s4 = r4 * 5; | ||
64 | |||
65 | /* init state */ | ||
66 | h0 = 0; | ||
67 | h1 = 0; | ||
68 | h2 = 0; | ||
69 | h3 = 0; | ||
70 | h4 = 0; | ||
71 | |||
72 | /* full blocks */ | ||
73 | if (inlen < 16) goto poly1305_donna_atmost15bytes; | ||
74 | poly1305_donna_16bytes: | ||
75 | m += 16; | ||
76 | inlen -= 16; | ||
77 | |||
78 | t0 = U8TO32_LE(m-16); | ||
79 | t1 = U8TO32_LE(m-12); | ||
80 | t2 = U8TO32_LE(m-8); | ||
81 | t3 = U8TO32_LE(m-4); | ||
82 | |||
83 | h0 += t0 & 0x3ffffff; | ||
84 | h1 += ((((uint64_t)t1 << 32) | t0) >> 26) & 0x3ffffff; | ||
85 | h2 += ((((uint64_t)t2 << 32) | t1) >> 20) & 0x3ffffff; | ||
86 | h3 += ((((uint64_t)t3 << 32) | t2) >> 14) & 0x3ffffff; | ||
87 | h4 += (t3 >> 8) | (1 << 24); | ||
88 | |||
89 | |||
90 | poly1305_donna_mul: | ||
91 | t[0] = mul32x32_64(h0,r0) + mul32x32_64(h1,s4) + mul32x32_64(h2,s3) + mul32x32_64(h3,s2) + mul32x32_64(h4,s1); | ||
92 | t[1] = mul32x32_64(h0,r1) + mul32x32_64(h1,r0) + mul32x32_64(h2,s4) + mul32x32_64(h3,s3) + mul32x32_64(h4,s2); | ||
93 | t[2] = mul32x32_64(h0,r2) + mul32x32_64(h1,r1) + mul32x32_64(h2,r0) + mul32x32_64(h3,s4) + mul32x32_64(h4,s3); | ||
94 | t[3] = mul32x32_64(h0,r3) + mul32x32_64(h1,r2) + mul32x32_64(h2,r1) + mul32x32_64(h3,r0) + mul32x32_64(h4,s4); | ||
95 | t[4] = mul32x32_64(h0,r4) + mul32x32_64(h1,r3) + mul32x32_64(h2,r2) + mul32x32_64(h3,r1) + mul32x32_64(h4,r0); | ||
96 | |||
97 | h0 = (uint32_t)t[0] & 0x3ffffff; c = (t[0] >> 26); | ||
98 | t[1] += c; h1 = (uint32_t)t[1] & 0x3ffffff; b = (uint32_t)(t[1] >> 26); | ||
99 | t[2] += b; h2 = (uint32_t)t[2] & 0x3ffffff; b = (uint32_t)(t[2] >> 26); | ||
100 | t[3] += b; h3 = (uint32_t)t[3] & 0x3ffffff; b = (uint32_t)(t[3] >> 26); | ||
101 | t[4] += b; h4 = (uint32_t)t[4] & 0x3ffffff; b = (uint32_t)(t[4] >> 26); | ||
102 | h0 += b * 5; | ||
103 | |||
104 | if (inlen >= 16) goto poly1305_donna_16bytes; | ||
105 | |||
106 | /* final bytes */ | ||
107 | poly1305_donna_atmost15bytes: | ||
108 | if (!inlen) goto poly1305_donna_finish; | ||
109 | |||
110 | for (j = 0; j < inlen; j++) mp[j] = m[j]; | ||
111 | mp[j++] = 1; | ||
112 | for (; j < 16; j++) mp[j] = 0; | ||
113 | inlen = 0; | ||
114 | |||
115 | t0 = U8TO32_LE(mp+0); | ||
116 | t1 = U8TO32_LE(mp+4); | ||
117 | t2 = U8TO32_LE(mp+8); | ||
118 | t3 = U8TO32_LE(mp+12); | ||
119 | |||
120 | h0 += t0 & 0x3ffffff; | ||
121 | h1 += ((((uint64_t)t1 << 32) | t0) >> 26) & 0x3ffffff; | ||
122 | h2 += ((((uint64_t)t2 << 32) | t1) >> 20) & 0x3ffffff; | ||
123 | h3 += ((((uint64_t)t3 << 32) | t2) >> 14) & 0x3ffffff; | ||
124 | h4 += (t3 >> 8); | ||
125 | |||
126 | goto poly1305_donna_mul; | ||
127 | |||
128 | poly1305_donna_finish: | ||
129 | b = h0 >> 26; h0 = h0 & 0x3ffffff; | ||
130 | h1 += b; b = h1 >> 26; h1 = h1 & 0x3ffffff; | ||
131 | h2 += b; b = h2 >> 26; h2 = h2 & 0x3ffffff; | ||
132 | h3 += b; b = h3 >> 26; h3 = h3 & 0x3ffffff; | ||
133 | h4 += b; b = h4 >> 26; h4 = h4 & 0x3ffffff; | ||
134 | h0 += b * 5; b = h0 >> 26; h0 = h0 & 0x3ffffff; | ||
135 | h1 += b; | ||
136 | |||
137 | g0 = h0 + 5; b = g0 >> 26; g0 &= 0x3ffffff; | ||
138 | g1 = h1 + b; b = g1 >> 26; g1 &= 0x3ffffff; | ||
139 | g2 = h2 + b; b = g2 >> 26; g2 &= 0x3ffffff; | ||
140 | g3 = h3 + b; b = g3 >> 26; g3 &= 0x3ffffff; | ||
141 | g4 = h4 + b - (1 << 26); | ||
142 | |||
143 | b = (g4 >> 31) - 1; | ||
144 | nb = ~b; | ||
145 | h0 = (h0 & nb) | (g0 & b); | ||
146 | h1 = (h1 & nb) | (g1 & b); | ||
147 | h2 = (h2 & nb) | (g2 & b); | ||
148 | h3 = (h3 & nb) | (g3 & b); | ||
149 | h4 = (h4 & nb) | (g4 & b); | ||
150 | |||
151 | f0 = ((h0 ) | (h1 << 26)) + (uint64_t)U8TO32_LE(&key[16]); | ||
152 | f1 = ((h1 >> 6) | (h2 << 20)) + (uint64_t)U8TO32_LE(&key[20]); | ||
153 | f2 = ((h2 >> 12) | (h3 << 14)) + (uint64_t)U8TO32_LE(&key[24]); | ||
154 | f3 = ((h3 >> 18) | (h4 << 8)) + (uint64_t)U8TO32_LE(&key[28]); | ||
155 | |||
156 | U32TO8_LE(&out[ 0], f0); f1 += (f0 >> 32); | ||
157 | U32TO8_LE(&out[ 4], f1); f2 += (f1 >> 32); | ||
158 | U32TO8_LE(&out[ 8], f2); f3 += (f2 >> 32); | ||
159 | U32TO8_LE(&out[12], f3); | ||
160 | } | ||