1
2
3
4
5
6
7
8
9#include <linux/kernel.h>
10#include <asm/unaligned.h>
11#include <crypto/internal/poly1305.h>
12
13void poly1305_core_setkey(struct poly1305_core_key *key,
14 const u8 raw_key[POLY1305_BLOCK_SIZE])
15{
16
17 key->key.r[0] = (get_unaligned_le32(&raw_key[0])) & 0x3ffffff;
18 key->key.r[1] = (get_unaligned_le32(&raw_key[3]) >> 2) & 0x3ffff03;
19 key->key.r[2] = (get_unaligned_le32(&raw_key[6]) >> 4) & 0x3ffc0ff;
20 key->key.r[3] = (get_unaligned_le32(&raw_key[9]) >> 6) & 0x3f03fff;
21 key->key.r[4] = (get_unaligned_le32(&raw_key[12]) >> 8) & 0x00fffff;
22
23
24 key->precomputed_s.r[0] = key->key.r[1] * 5;
25 key->precomputed_s.r[1] = key->key.r[2] * 5;
26 key->precomputed_s.r[2] = key->key.r[3] * 5;
27 key->precomputed_s.r[3] = key->key.r[4] * 5;
28}
29EXPORT_SYMBOL(poly1305_core_setkey);
30
31void poly1305_core_blocks(struct poly1305_state *state,
32 const struct poly1305_core_key *key, const void *src,
33 unsigned int nblocks, u32 hibit)
34{
35 const u8 *input = src;
36 u32 r0, r1, r2, r3, r4;
37 u32 s1, s2, s3, s4;
38 u32 h0, h1, h2, h3, h4;
39 u64 d0, d1, d2, d3, d4;
40 u32 c;
41
42 if (!nblocks)
43 return;
44
45 hibit <<= 24;
46
47 r0 = key->key.r[0];
48 r1 = key->key.r[1];
49 r2 = key->key.r[2];
50 r3 = key->key.r[3];
51 r4 = key->key.r[4];
52
53 s1 = key->precomputed_s.r[0];
54 s2 = key->precomputed_s.r[1];
55 s3 = key->precomputed_s.r[2];
56 s4 = key->precomputed_s.r[3];
57
58 h0 = state->h[0];
59 h1 = state->h[1];
60 h2 = state->h[2];
61 h3 = state->h[3];
62 h4 = state->h[4];
63
64 do {
65
66 h0 += (get_unaligned_le32(&input[0])) & 0x3ffffff;
67 h1 += (get_unaligned_le32(&input[3]) >> 2) & 0x3ffffff;
68 h2 += (get_unaligned_le32(&input[6]) >> 4) & 0x3ffffff;
69 h3 += (get_unaligned_le32(&input[9]) >> 6) & 0x3ffffff;
70 h4 += (get_unaligned_le32(&input[12]) >> 8) | hibit;
71
72
73 d0 = ((u64)h0 * r0) + ((u64)h1 * s4) +
74 ((u64)h2 * s3) + ((u64)h3 * s2) +
75 ((u64)h4 * s1);
76 d1 = ((u64)h0 * r1) + ((u64)h1 * r0) +
77 ((u64)h2 * s4) + ((u64)h3 * s3) +
78 ((u64)h4 * s2);
79 d2 = ((u64)h0 * r2) + ((u64)h1 * r1) +
80 ((u64)h2 * r0) + ((u64)h3 * s4) +
81 ((u64)h4 * s3);
82 d3 = ((u64)h0 * r3) + ((u64)h1 * r2) +
83 ((u64)h2 * r1) + ((u64)h3 * r0) +
84 ((u64)h4 * s4);
85 d4 = ((u64)h0 * r4) + ((u64)h1 * r3) +
86 ((u64)h2 * r2) + ((u64)h3 * r1) +
87 ((u64)h4 * r0);
88
89
90 c = (u32)(d0 >> 26);
91 h0 = (u32)d0 & 0x3ffffff;
92 d1 += c;
93 c = (u32)(d1 >> 26);
94 h1 = (u32)d1 & 0x3ffffff;
95 d2 += c;
96 c = (u32)(d2 >> 26);
97 h2 = (u32)d2 & 0x3ffffff;
98 d3 += c;
99 c = (u32)(d3 >> 26);
100 h3 = (u32)d3 & 0x3ffffff;
101 d4 += c;
102 c = (u32)(d4 >> 26);
103 h4 = (u32)d4 & 0x3ffffff;
104 h0 += c * 5;
105 c = (h0 >> 26);
106 h0 = h0 & 0x3ffffff;
107 h1 += c;
108
109 input += POLY1305_BLOCK_SIZE;
110 } while (--nblocks);
111
112 state->h[0] = h0;
113 state->h[1] = h1;
114 state->h[2] = h2;
115 state->h[3] = h3;
116 state->h[4] = h4;
117}
118EXPORT_SYMBOL(poly1305_core_blocks);
119
120void poly1305_core_emit(const struct poly1305_state *state, const u32 nonce[4],
121 void *dst)
122{
123 u8 *mac = dst;
124 u32 h0, h1, h2, h3, h4, c;
125 u32 g0, g1, g2, g3, g4;
126 u64 f;
127 u32 mask;
128
129
130 h0 = state->h[0];
131 h1 = state->h[1];
132 h2 = state->h[2];
133 h3 = state->h[3];
134 h4 = state->h[4];
135
136 c = h1 >> 26;
137 h1 = h1 & 0x3ffffff;
138 h2 += c;
139 c = h2 >> 26;
140 h2 = h2 & 0x3ffffff;
141 h3 += c;
142 c = h3 >> 26;
143 h3 = h3 & 0x3ffffff;
144 h4 += c;
145 c = h4 >> 26;
146 h4 = h4 & 0x3ffffff;
147 h0 += c * 5;
148 c = h0 >> 26;
149 h0 = h0 & 0x3ffffff;
150 h1 += c;
151
152
153 g0 = h0 + 5;
154 c = g0 >> 26;
155 g0 &= 0x3ffffff;
156 g1 = h1 + c;
157 c = g1 >> 26;
158 g1 &= 0x3ffffff;
159 g2 = h2 + c;
160 c = g2 >> 26;
161 g2 &= 0x3ffffff;
162 g3 = h3 + c;
163 c = g3 >> 26;
164 g3 &= 0x3ffffff;
165 g4 = h4 + c - (1UL << 26);
166
167
168 mask = (g4 >> ((sizeof(u32) * 8) - 1)) - 1;
169 g0 &= mask;
170 g1 &= mask;
171 g2 &= mask;
172 g3 &= mask;
173 g4 &= mask;
174 mask = ~mask;
175
176 h0 = (h0 & mask) | g0;
177 h1 = (h1 & mask) | g1;
178 h2 = (h2 & mask) | g2;
179 h3 = (h3 & mask) | g3;
180 h4 = (h4 & mask) | g4;
181
182
183 h0 = ((h0) | (h1 << 26)) & 0xffffffff;
184 h1 = ((h1 >> 6) | (h2 << 20)) & 0xffffffff;
185 h2 = ((h2 >> 12) | (h3 << 14)) & 0xffffffff;
186 h3 = ((h3 >> 18) | (h4 << 8)) & 0xffffffff;
187
188 if (likely(nonce)) {
189
190 f = (u64)h0 + nonce[0];
191 h0 = (u32)f;
192 f = (u64)h1 + nonce[1] + (f >> 32);
193 h1 = (u32)f;
194 f = (u64)h2 + nonce[2] + (f >> 32);
195 h2 = (u32)f;
196 f = (u64)h3 + nonce[3] + (f >> 32);
197 h3 = (u32)f;
198 }
199
200 put_unaligned_le32(h0, &mac[0]);
201 put_unaligned_le32(h1, &mac[4]);
202 put_unaligned_le32(h2, &mac[8]);
203 put_unaligned_le32(h3, &mac[12]);
204}
205EXPORT_SYMBOL(poly1305_core_emit);
206
