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Added DRBG_HMAC & DRBG_HASH + Added defaults for setting DRBG for master/public/private + renamed generate_counter back to reseed_counter + generated new cavs data tests
Reviewed-by: Matt Caswell <[email protected]> Reviewed-by: Paul Dale <[email protected]> (Merged from #6779)
1 parent 1362190 commit 8bf3665

18 files changed

+18527
-170426
lines changed

‎crypto/rand/build.info‎

Lines changed: 3 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -1,4 +1,6 @@
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LIBS=../../libcrypto
22
SOURCE[../../libcrypto]=\
33
randfile.c rand_lib.c rand_err.c rand_egd.c \
4-
rand_win.c rand_unix.c rand_vms.c drbg_lib.c drbg_ctr.c
4+
rand_win.c rand_unix.c rand_vms.c drbg_lib.c drbg_ctr.c \
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drbg_hash.c drbg_hmac.c
6+

‎crypto/rand/drbg_ctr.c‎

Lines changed: 1 addition & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -13,12 +13,11 @@
1313
#include <openssl/err.h>
1414
#include <openssl/rand.h>
1515
#include "internal/thread_once.h"
16-
#include "internal/thread_once.h"
1716
#include "rand_lcl.h"
17+
1818
/*
1919
* Implementation of NIST SP 800-90A CTR DRBG.
2020
*/
21-
2221
static void inc_128(RAND_DRBG_CTR *ctr)
2322
{
2423
int i;

‎crypto/rand/drbg_hash.c‎

Lines changed: 347 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,347 @@
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/*
2+
* Copyright 2011-2018 The OpenSSL Project Authors. All Rights Reserved.
3+
*
4+
* Licensed under the OpenSSL license (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+
#include <assert.h>
11+
#include <stdlib.h>
12+
#include <string.h>
13+
#include <openssl/crypto.h>
14+
#include <openssl/err.h>
15+
#include <openssl/rand.h>
16+
#include "internal/thread_once.h"
17+
#include "rand_lcl.h"
18+
19+
/* 440 bits from SP800-90Ar1 10.1 table 2 */
20+
#define HASH_PRNG_SMALL_SEEDLEN (440/8)
21+
/* Determine what seedlen to use based on the block length */
22+
#define MAX_BLOCKLEN_USING_SMALL_SEEDLEN (256/8)
23+
#define INBYTE_IGNORE ((unsigned char)0xFF)
24+
25+
26+
/*
27+
* SP800-90Ar1 10.3.1 Derivation function using a Hash Function (Hash_df).
28+
* The input string used is composed of:
29+
* inbyte - An optional leading byte (ignore if equal to INBYTE_IGNORE)
30+
* in - input string 1 (A Non NULL value).
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* in2 - optional input string (Can be NULL).
32+
* in3 - optional input string (Can be NULL).
33+
* These are concatenated as part of the DigestUpdate process.
34+
*/
35+
static int hash_df(RAND_DRBG *drbg, unsigned char *out,
36+
const unsigned char inbyte,
37+
const unsigned char *in, size_t inlen,
38+
const unsigned char *in2, size_t in2len,
39+
const unsigned char *in3, size_t in3len)
40+
{
41+
RAND_DRBG_HASH *hash = &drbg->data.hash;
42+
EVP_MD_CTX *ctx = hash->ctx;
43+
unsigned char *vtmp = hash->vtmp;
44+
/* tmp = counter || num_bits_returned || [inbyte] */
45+
unsigned char tmp[1 + 4 + 1];
46+
int tmp_sz = 0;
47+
size_t outlen = drbg->seedlen;
48+
size_t num_bits_returned = outlen * 8;
49+
/*
50+
* No need to check outlen size here, as the standard only ever needs
51+
* seedlen bytes which is always less than the maximum permitted.
52+
*/
53+
54+
/* (Step 3) counter = 1 (tmp[0] is the 8 bit counter) */
55+
tmp[tmp_sz++] = 1;
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/* tmp[1..4] is the fixed 32 bit no_of_bits_to_return */
57+
tmp[tmp_sz++] = (unsigned char)((num_bits_returned >> 24) & 0xff);
58+
tmp[tmp_sz++] = (unsigned char)((num_bits_returned >> 16) & 0xff);
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tmp[tmp_sz++] = (unsigned char)((num_bits_returned >> 8) & 0xff);
60+
tmp[tmp_sz++] = (unsigned char)(num_bits_returned & 0xff);
61+
/* Tack the additional input byte onto the end of tmp if it exists */
62+
if (inbyte != INBYTE_IGNORE)
63+
tmp[tmp_sz++] = inbyte;
64+
65+
/* (Step 4) */
66+
for (;;) {
67+
/*
68+
* (Step 4.1) out = out || Hash(tmp || in || [in2] || [in3])
69+
* (where tmp = counter || num_bits_returned || [inbyte])
70+
*/
71+
if (!(EVP_DigestInit_ex(ctx, hash->md, NULL)
72+
&& EVP_DigestUpdate(ctx, tmp, tmp_sz)
73+
&& EVP_DigestUpdate(ctx, in, inlen)
74+
&& (in2 == NULL || EVP_DigestUpdate(ctx, in2, in2len))
75+
&& (in3 == NULL || EVP_DigestUpdate(ctx, in3, in3len))))
76+
return 0;
77+
78+
if (outlen < hash->blocklen) {
79+
if (!EVP_DigestFinal(ctx, vtmp, NULL))
80+
return 0;
81+
memcpy(out, vtmp, outlen);
82+
OPENSSL_cleanse(vtmp, hash->blocklen);
83+
break;
84+
} else if(!EVP_DigestFinal(ctx, out, NULL)) {
85+
return 0;
86+
}
87+
88+
outlen -= hash->blocklen;
89+
if (outlen == 0)
90+
break;
91+
/* (Step 4.2) counter++ */
92+
tmp[0]++;
93+
out += hash->blocklen;
94+
}
95+
return 1;
96+
}
97+
98+
/* Helper function that just passes 2 input parameters to hash_df() */
99+
static int hash_df1(RAND_DRBG *drbg, unsigned char *out,
100+
const unsigned char in_byte,
101+
const unsigned char *in1, size_t in1len)
102+
{
103+
return hash_df(drbg, out, in_byte, in1, in1len, NULL, 0, NULL, 0);
104+
}
105+
106+
/*
107+
* Add 2 byte buffers together. The first elements in each buffer are the top
108+
* most bytes. The result is stored in the dst buffer.
109+
* The final carry is ignored i.e: dst = (dst + in) mod (2^seedlen_bits).
110+
* where dst size is drbg->seedlen, and inlen <= drbg->seedlen.
111+
*/
112+
static int add_bytes(RAND_DRBG *drbg, unsigned char *dst,
113+
unsigned char *in, size_t inlen)
114+
{
115+
size_t i;
116+
int result;
117+
const unsigned char *add;
118+
unsigned char carry = 0, *d;
119+
120+
assert(drbg->seedlen >= 1 && inlen >= 1 && inlen <= drbg->seedlen);
121+
122+
d = &dst[drbg->seedlen - 1];
123+
add = &in[inlen - 1];
124+
125+
for (i = inlen; i > 0; i--, d--, add--) {
126+
result = *d + *add + carry;
127+
carry = (unsigned char)(result >> 8);
128+
*d = (unsigned char)(result & 0xff);
129+
}
130+
131+
if (carry != 0) {
132+
/* Add the carry to the top of the dst if inlen is not the same size */
133+
for (i = drbg->seedlen - inlen; i > 0; --i, d--) {
134+
*d += 1; /* Carry can only be 1 */
135+
if (*d != 0) /* exit if carry doesnt propagate to the next byte */
136+
break;
137+
}
138+
}
139+
return 1;
140+
}
141+
142+
/* V = (V + Hash(inbyte || V || [additional_input]) mod (2^seedlen) */
143+
static int add_hash_to_v(RAND_DRBG *drbg, unsigned char inbyte,
144+
const unsigned char *adin, size_t adinlen)
145+
{
146+
RAND_DRBG_HASH *hash = &drbg->data.hash;
147+
EVP_MD_CTX *ctx = hash->ctx;
148+
149+
return EVP_DigestInit_ex(ctx, hash->md, NULL)
150+
&& EVP_DigestUpdate(ctx, &inbyte, 1)
151+
&& EVP_DigestUpdate(ctx, hash->V, drbg->seedlen)
152+
&& (adin == NULL || EVP_DigestUpdate(ctx, adin, adinlen))
153+
&& EVP_DigestFinal(ctx, hash->vtmp, NULL)
154+
&& add_bytes(drbg, hash->V, hash->vtmp, hash->blocklen);
155+
}
156+
157+
/*
158+
* The Hashgen() as listed in SP800-90Ar1 10.1.1.4 Hash_DRBG_Generate_Process.
159+
*
160+
* drbg contains the current value of V.
161+
* outlen is the requested number of bytes.
162+
* out is a buffer to return the generated bits.
163+
*
164+
* The algorithm to generate the bits is:
165+
* data = V
166+
* w = NULL
167+
* for (i = 1 to m) {
168+
* W = W || Hash(data)
169+
* data = (data + 1) mod (2^seedlen)
170+
* }
171+
* out = Leftmost(W, outlen)
172+
*
173+
* Returns zero if an error occurs otherwise it returns 1.
174+
*/
175+
static int hash_gen(RAND_DRBG *drbg, unsigned char *out, size_t outlen)
176+
{
177+
RAND_DRBG_HASH *hash = &drbg->data.hash;
178+
unsigned char one = 1;
179+
180+
if (outlen == 0)
181+
return 1;
182+
memcpy(hash->vtmp, hash->V, drbg->seedlen);
183+
for(;;) {
184+
if (!EVP_DigestInit_ex(hash->ctx, hash->md, NULL)
185+
|| !EVP_DigestUpdate(hash->ctx, hash->vtmp, drbg->seedlen))
186+
return 0;
187+
188+
if (outlen < hash->blocklen) {
189+
if (!EVP_DigestFinal(hash->ctx, hash->vtmp, NULL))
190+
return 0;
191+
memcpy(out, hash->vtmp, outlen);
192+
return 1;
193+
} else {
194+
if (!EVP_DigestFinal(hash->ctx, out, NULL))
195+
return 0;
196+
outlen -= hash->blocklen;
197+
if (outlen == 0)
198+
break;
199+
out += hash->blocklen;
200+
}
201+
add_bytes(drbg, hash->vtmp, &one, 1);
202+
}
203+
return 1;
204+
}
205+
206+
/*
207+
* SP800-90Ar1 10.1.1.2 Hash_DRBG_Instantiate_Process:
208+
*
209+
* ent is entropy input obtained from a randomness source of length ent_len.
210+
* nonce is a string of bytes of length nonce_len.
211+
* pstr is a personalization string received from an application. May be NULL.
212+
*
213+
* Returns zero if an error occurs otherwise it returns 1.
214+
*/
215+
static int drbg_hash_instantiate(RAND_DRBG *drbg,
216+
const unsigned char *ent, size_t ent_len,
217+
const unsigned char *nonce, size_t nonce_len,
218+
const unsigned char *pstr, size_t pstr_len)
219+
{
220+
RAND_DRBG_HASH *hash = &drbg->data.hash;
221+
222+
/* (Step 1-3) V = Hash_df(entropy||nonce||pers, seedlen) */
223+
return hash_df(drbg, hash->V, INBYTE_IGNORE,
224+
ent, ent_len, nonce, nonce_len, pstr, pstr_len)
225+
/* (Step 4) C = Hash_df(0x00||V, seedlen) */
226+
&& hash_df1(drbg, hash->C, 0x00, hash->V, drbg->seedlen);
227+
}
228+
229+
/*
230+
* SP800-90Ar1 10.1.1.3 Hash_DRBG_Reseed_Process:
231+
*
232+
* ent is entropy input bytes obtained from a randomness source.
233+
* addin is additional input received from an application. May be NULL.
234+
*
235+
* Returns zero if an error occurs otherwise it returns 1.
236+
*/
237+
static int drbg_hash_reseed(RAND_DRBG *drbg,
238+
const unsigned char *ent, size_t ent_len,
239+
const unsigned char *adin, size_t adin_len)
240+
{
241+
RAND_DRBG_HASH *hash = &drbg->data.hash;
242+
243+
/* (Step 1-2) V = Hash_df(0x01 || V || entropy_input || additional_input)*/
244+
/* V about to be updated so use C as output instead */
245+
if (!hash_df(drbg, hash->C, 0x01, hash->V, drbg->seedlen, ent, ent_len,
246+
adin, adin_len))
247+
return 0;
248+
memcpy(hash->V, hash->C, drbg->seedlen);
249+
/* (Step 4) C = Hash_df(0x00||V, seedlen) */
250+
return hash_df1(drbg, hash->C, 0x00, hash->V, drbg->seedlen);
251+
}
252+
253+
/*
254+
* SP800-90Ar1 10.1.1.4 Hash_DRBG_Generate_Process:
255+
*
256+
* Generates pseudo random bytes using the drbg.
257+
* out is a buffer to fill with outlen bytes of pseudo random data.
258+
* addin is additional input received from an application. May be NULL.
259+
*
260+
* Returns zero if an error occurs otherwise it returns 1.
261+
*/
262+
static int drbg_hash_generate(RAND_DRBG *drbg,
263+
unsigned char *out, size_t outlen,
264+
const unsigned char *adin, size_t adin_len)
265+
{
266+
RAND_DRBG_HASH *hash = &drbg->data.hash;
267+
unsigned char counter[4];
268+
int reseed_counter = drbg->reseed_gen_counter;
269+
270+
counter[0] = (unsigned char)((reseed_counter >> 24) & 0xff);
271+
counter[1] = (unsigned char)((reseed_counter >> 16) & 0xff);
272+
counter[2] = (unsigned char)((reseed_counter >> 8) & 0xff);
273+
counter[3] = (unsigned char)(reseed_counter & 0xff);
274+
275+
return (adin == NULL
276+
/* (Step 2) if adin != NULL then V = V + Hash(0x02||V||adin) */
277+
|| adin_len == 0
278+
|| add_hash_to_v(drbg, 0x02, adin, adin_len))
279+
/* (Step 3) Hashgen(outlen, V) */
280+
&& hash_gen(drbg, out, outlen)
281+
/* (Step 4/5) H = V = (V + Hash(0x03||V) mod (2^seedlen_bits) */
282+
&& add_hash_to_v(drbg, 0x03, NULL, 0)
283+
/* (Step 5) V = (V + H + C + reseed_counter) mod (2^seedlen_bits) */
284+
/* V = (V + C) mod (2^seedlen_bits) */
285+
&& add_bytes(drbg, hash->V, hash->C, drbg->seedlen)
286+
/* V = (V + reseed_counter) mod (2^seedlen_bits) */
287+
&& add_bytes(drbg, hash->V, counter, 4);
288+
}
289+
290+
static int drbg_hash_uninstantiate(RAND_DRBG *drbg)
291+
{
292+
EVP_MD_CTX_free(drbg->data.hash.ctx);
293+
OPENSSL_cleanse(&drbg->data.hash, sizeof(drbg->data.hash));
294+
return 1;
295+
}
296+
297+
static RAND_DRBG_METHOD drbg_hash_meth = {
298+
drbg_hash_instantiate,
299+
drbg_hash_reseed,
300+
drbg_hash_generate,
301+
drbg_hash_uninstantiate
302+
};
303+
304+
int drbg_hash_init(RAND_DRBG *drbg)
305+
{
306+
const EVP_MD *md;
307+
RAND_DRBG_HASH *hash = &drbg->data.hash;
308+
309+
/* Any approved digest is allowed */
310+
md = EVP_get_digestbynid(drbg->type);
311+
if (md == NULL)
312+
return 0;
313+
314+
drbg->meth = &drbg_hash_meth;
315+
hash->md = md;
316+
317+
if (hash->ctx == NULL) {
318+
hash->ctx = EVP_MD_CTX_new();
319+
if (hash->ctx == NULL)
320+
return 0;
321+
}
322+
323+
/* These are taken from SP 800-90 10.1 Table 2 */
324+
hash->blocklen = EVP_MD_size(md);
325+
/* See SP800-57 Part1 Rev4 5.6.1 Table 3 */
326+
drbg->strength = 64 * (hash->blocklen >> 3);
327+
if (drbg->strength > 256)
328+
drbg->strength = 256;
329+
if (hash->blocklen > MAX_BLOCKLEN_USING_SMALL_SEEDLEN)
330+
drbg->seedlen = HASH_PRNG_MAX_SEEDLEN;
331+
else
332+
drbg->seedlen = HASH_PRNG_SMALL_SEEDLEN;
333+
334+
drbg->min_entropylen = drbg->strength / 8;
335+
drbg->max_entropylen = DRBG_MINMAX_FACTOR * drbg->min_entropylen;
336+
337+
drbg->min_noncelen = drbg->min_entropylen / 2;
338+
drbg->max_noncelen = DRBG_MINMAX_FACTOR * drbg->min_noncelen;
339+
340+
drbg->max_perslen = DRBG_MAX_LENGTH;
341+
drbg->max_adinlen = DRBG_MAX_LENGTH;
342+
343+
/* Maximum number of bits per request = 2^19 = 2^16 bytes */
344+
drbg->max_request = 1 << 16;
345+
346+
return 1;
347+
}

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