1 /*
2 * Copyright 2017-2022 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10 /* Based on https://131002.net/siphash C reference implementation */
11 /*
12 SipHash reference C implementation
13
14 Copyright (c) 2012-2016 Jean-Philippe Aumasson
15 Copyright (c) 2012-2014 Daniel J. Bernstein
16
17 To the extent possible under law, the author(s) have dedicated all copyright
18 and related and neighboring rights to this software to the public domain
19 worldwide. This software is distributed without any warranty.
20
21 You should have received a copy of the CC0 Public Domain Dedication along
22 with this software. If not, see
23 <http://creativecommons.org/publicdomain/zero/1.0/>.
24 */
25
26 #include <stdlib.h>
27 #include <string.h>
28 #include <openssl/crypto.h>
29
30 #include "crypto/siphash.h"
31
32 #define ROTL(x, b) (uint64_t)(((x) << (b)) | ((x) >> (64 - (b))))
33
34 #define U32TO8_LE(p, v) \
35 (p)[0] = (uint8_t)((v)); \
36 (p)[1] = (uint8_t)((v) >> 8); \
37 (p)[2] = (uint8_t)((v) >> 16); \
38 (p)[3] = (uint8_t)((v) >> 24);
39
40 #define U64TO8_LE(p, v) \
41 U32TO8_LE((p), (uint32_t)((v))); \
42 U32TO8_LE((p) + 4, (uint32_t)((v) >> 32));
43
44 #define U8TO64_LE(p) \
45 (((uint64_t)((p)[0])) | ((uint64_t)((p)[1]) << 8) | \
46 ((uint64_t)((p)[2]) << 16) | ((uint64_t)((p)[3]) << 24) | \
47 ((uint64_t)((p)[4]) << 32) | ((uint64_t)((p)[5]) << 40) | \
48 ((uint64_t)((p)[6]) << 48) | ((uint64_t)((p)[7]) << 56))
49
50 #define SIPROUND \
51 do { \
52 v0 += v1; \
53 v1 = ROTL(v1, 13); \
54 v1 ^= v0; \
55 v0 = ROTL(v0, 32); \
56 v2 += v3; \
57 v3 = ROTL(v3, 16); \
58 v3 ^= v2; \
59 v0 += v3; \
60 v3 = ROTL(v3, 21); \
61 v3 ^= v0; \
62 v2 += v1; \
63 v1 = ROTL(v1, 17); \
64 v1 ^= v2; \
65 v2 = ROTL(v2, 32); \
66 } while (0)
67
SipHash_ctx_size(void)68 size_t SipHash_ctx_size(void)
69 {
70 return sizeof(SIPHASH);
71 }
72
SipHash_hash_size(SIPHASH * ctx)73 size_t SipHash_hash_size(SIPHASH *ctx)
74 {
75 return ctx->hash_size;
76 }
77
siphash_adjust_hash_size(size_t hash_size)78 static size_t siphash_adjust_hash_size(size_t hash_size)
79 {
80 if (hash_size == 0)
81 hash_size = SIPHASH_MAX_DIGEST_SIZE;
82 return hash_size;
83 }
84
SipHash_set_hash_size(SIPHASH * ctx,size_t hash_size)85 int SipHash_set_hash_size(SIPHASH *ctx, size_t hash_size)
86 {
87 hash_size = siphash_adjust_hash_size(hash_size);
88 if (hash_size != SIPHASH_MIN_DIGEST_SIZE
89 && hash_size != SIPHASH_MAX_DIGEST_SIZE)
90 return 0;
91
92 /*
93 * It's possible that the key was set first. If the hash size changes,
94 * we need to adjust v1 (see SipHash_Init().
95 */
96
97 /* Start by adjusting the stored size, to make things easier */
98 ctx->hash_size = siphash_adjust_hash_size(ctx->hash_size);
99
100 /* Now, adjust ctx->v1 if the old and the new size differ */
101 if ((size_t)ctx->hash_size != hash_size) {
102 ctx->v1 ^= 0xee;
103 ctx->hash_size = hash_size;
104 }
105 return 1;
106 }
107
108 /* hash_size = crounds = drounds = 0 means SipHash24 with 16-byte output */
SipHash_Init(SIPHASH * ctx,const unsigned char * k,int crounds,int drounds)109 int SipHash_Init(SIPHASH *ctx, const unsigned char *k, int crounds, int drounds)
110 {
111 uint64_t k0 = U8TO64_LE(k);
112 uint64_t k1 = U8TO64_LE(k + 8);
113
114 /* If the hash size wasn't set, i.e. is zero */
115 ctx->hash_size = siphash_adjust_hash_size(ctx->hash_size);
116
117 if (drounds == 0)
118 drounds = SIPHASH_D_ROUNDS;
119 if (crounds == 0)
120 crounds = SIPHASH_C_ROUNDS;
121
122 ctx->crounds = crounds;
123 ctx->drounds = drounds;
124
125 ctx->len = 0;
126 ctx->total_inlen = 0;
127
128 ctx->v0 = 0x736f6d6570736575ULL ^ k0;
129 ctx->v1 = 0x646f72616e646f6dULL ^ k1;
130 ctx->v2 = 0x6c7967656e657261ULL ^ k0;
131 ctx->v3 = 0x7465646279746573ULL ^ k1;
132
133 if (ctx->hash_size == SIPHASH_MAX_DIGEST_SIZE)
134 ctx->v1 ^= 0xee;
135
136 return 1;
137 }
138
SipHash_Update(SIPHASH * ctx,const unsigned char * in,size_t inlen)139 void SipHash_Update(SIPHASH *ctx, const unsigned char *in, size_t inlen)
140 {
141 uint64_t m;
142 const uint8_t *end;
143 int left;
144 unsigned int i;
145 uint64_t v0 = ctx->v0;
146 uint64_t v1 = ctx->v1;
147 uint64_t v2 = ctx->v2;
148 uint64_t v3 = ctx->v3;
149
150 ctx->total_inlen += inlen;
151
152 if (ctx->len) {
153 /* deal with leavings */
154 size_t available = SIPHASH_BLOCK_SIZE - ctx->len;
155
156 /* not enough to fill leavings */
157 if (inlen < available) {
158 memcpy(&ctx->leavings[ctx->len], in, inlen);
159 ctx->len += inlen;
160 return;
161 }
162
163 /* copy data into leavings and reduce input */
164 memcpy(&ctx->leavings[ctx->len], in, available);
165 inlen -= available;
166 in += available;
167
168 /* process leavings */
169 m = U8TO64_LE(ctx->leavings);
170 v3 ^= m;
171 for (i = 0; i < ctx->crounds; ++i)
172 SIPROUND;
173 v0 ^= m;
174 }
175 left = inlen & (SIPHASH_BLOCK_SIZE-1); /* gets put into leavings */
176 end = in + inlen - left;
177
178 for (; in != end; in += 8) {
179 m = U8TO64_LE(in);
180 v3 ^= m;
181 for (i = 0; i < ctx->crounds; ++i)
182 SIPROUND;
183 v0 ^= m;
184 }
185
186 /* save leavings and other ctx */
187 if (left)
188 memcpy(ctx->leavings, end, left);
189 ctx->len = left;
190
191 ctx->v0 = v0;
192 ctx->v1 = v1;
193 ctx->v2 = v2;
194 ctx->v3 = v3;
195 }
196
SipHash_Final(SIPHASH * ctx,unsigned char * out,size_t outlen)197 int SipHash_Final(SIPHASH *ctx, unsigned char *out, size_t outlen)
198 {
199 /* finalize hash */
200 unsigned int i;
201 uint64_t b = ctx->total_inlen << 56;
202 uint64_t v0 = ctx->v0;
203 uint64_t v1 = ctx->v1;
204 uint64_t v2 = ctx->v2;
205 uint64_t v3 = ctx->v3;
206
207 if (ctx->crounds == 0 || outlen == 0 || outlen != (size_t)ctx->hash_size)
208 return 0;
209
210 switch (ctx->len) {
211 case 7:
212 b |= ((uint64_t)ctx->leavings[6]) << 48;
213 /* fall thru */
214 case 6:
215 b |= ((uint64_t)ctx->leavings[5]) << 40;
216 /* fall thru */
217 case 5:
218 b |= ((uint64_t)ctx->leavings[4]) << 32;
219 /* fall thru */
220 case 4:
221 b |= ((uint64_t)ctx->leavings[3]) << 24;
222 /* fall thru */
223 case 3:
224 b |= ((uint64_t)ctx->leavings[2]) << 16;
225 /* fall thru */
226 case 2:
227 b |= ((uint64_t)ctx->leavings[1]) << 8;
228 /* fall thru */
229 case 1:
230 b |= ((uint64_t)ctx->leavings[0]);
231 case 0:
232 break;
233 }
234
235 v3 ^= b;
236 for (i = 0; i < ctx->crounds; ++i)
237 SIPROUND;
238 v0 ^= b;
239 if (ctx->hash_size == SIPHASH_MAX_DIGEST_SIZE)
240 v2 ^= 0xee;
241 else
242 v2 ^= 0xff;
243 for (i = 0; i < ctx->drounds; ++i)
244 SIPROUND;
245 b = v0 ^ v1 ^ v2 ^ v3;
246 U64TO8_LE(out, b);
247 if (ctx->hash_size == SIPHASH_MIN_DIGEST_SIZE)
248 return 1;
249 v1 ^= 0xdd;
250 for (i = 0; i < ctx->drounds; ++i)
251 SIPROUND;
252 b = v0 ^ v1 ^ v2 ^ v3;
253 U64TO8_LE(out + 8, b);
254 return 1;
255 }
256
