2 * Copyright 2016 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the OpenSSL licenses, (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 * https://www.openssl.org/source/license.html
8 * or in the file LICENSE in the source distribution.
12 * Confirm that if (d, r) = a / b, then b * d + r == a, and that sign(d) ==
13 * sign(a), and 0 <= r <= b
17 #include <openssl/bn.h>
18 #include <openssl/err.h>
28 int FuzzerInitialize(int *argc, char ***argv)
37 OPENSSL_init_crypto(OPENSSL_INIT_LOAD_CRYPTO_STRINGS, NULL);
43 int FuzzerTestOneInput(const uint8_t *buf, size_t len)
46 size_t l1 = 0, l2 = 0;
47 /* s1 and s2 will be the signs for b1 and b2. */
50 /* We are going to split the buffer in two, sizes l1 and l2, giving b1 and
55 /* Use first byte to divide the remaining buffer into 3Fths. I admit
56 * this disallows some number sizes. If it matters, better ideas are
59 l1 = ((buf[0] & 0x3f) * len) / 0x3f;
65 OPENSSL_assert(BN_bin2bn(buf, l1, b1) == b1);
66 BN_set_negative(b1, s1);
67 OPENSSL_assert(BN_bin2bn(buf + l1, l2, b2) == b2);
68 BN_set_negative(b2, s2);
70 /* divide by 0 is an error */
76 OPENSSL_assert(BN_div(b3, b4, b1, b2, ctx));
78 success = BN_is_zero(b3) && BN_is_zero(b4);
79 else if (BN_is_negative(b1))
80 success = (BN_is_negative(b3) != BN_is_negative(b2) || BN_is_zero(b3))
81 && (BN_is_negative(b4) || BN_is_zero(b4));
83 success = (BN_is_negative(b3) == BN_is_negative(b2) || BN_is_zero(b3))
84 && (!BN_is_negative(b4) || BN_is_zero(b4));
85 OPENSSL_assert(BN_mul(b5, b3, b2, ctx));
86 OPENSSL_assert(BN_add(b5, b5, b4));
88 success = success && BN_cmp(b5, b1) == 0;
90 BN_print_fp(stdout, b1);
92 BN_print_fp(stdout, b2);
94 BN_print_fp(stdout, b3);
96 BN_print_fp(stdout, b4);
98 BN_print_fp(stdout, b5);
100 printf("%d %d %d %d %d %d %d\n", BN_is_negative(b1),
102 BN_is_negative(b3), BN_is_negative(b4), BN_is_zero(b4),
103 BN_is_negative(b3) != BN_is_negative(b2)
104 && (BN_is_negative(b4) || BN_is_zero(b4)),
110 OPENSSL_assert(success);
116 void FuzzerCleanup(void)