1RSA_GENERATE_KEY(3) OpenSSL RSA_GENERATE_KEY(3)
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6 RSA_generate_key_ex, RSA_generate_key, RSA_generate_multi_prime_key -
7 generate RSA key pair
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10 #include <openssl/rsa.h>
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12 int RSA_generate_key_ex(RSA *rsa, int bits, BIGNUM *e, BN_GENCB *cb);
13 int RSA_generate_multi_prime_key(RSA *rsa, int bits, int primes, BIGNUM *e, BN_GENCB *cb);
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15 Deprecated:
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17 #if OPENSSL_API_COMPAT < 0x00908000L
18 RSA *RSA_generate_key(int num, unsigned long e,
19 void (*callback)(int, int, void *), void *cb_arg);
20 #endif
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23 RSA_generate_key_ex() generates a 2-prime RSA key pair and stores it in
24 the RSA structure provided in rsa. The pseudo-random number generator
25 must be seeded prior to calling RSA_generate_key_ex().
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27 RSA_generate_multi_prime_key() generates a multi-prime RSA key pair and
28 stores it in the RSA structure provided in rsa. The number of primes is
29 given by the primes parameter. The pseudo-random number generator must
30 be seeded prior to calling RSA_generate_multi_prime_key().
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32 The modulus size will be of length bits, the number of primes to form
33 the modulus will be primes, and the public exponent will be e. Key
34 sizes with num < 1024 should be considered insecure. The exponent is an
35 odd number, typically 3, 17 or 65537.
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37 In order to maintain adequate security level, the maximum number of
38 permitted primes depends on modulus bit length:
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40 <1024 | >=1024 | >=4096 | >=8192
41 ------+--------+--------+-------
42 2 | 3 | 4 | 5
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44 A callback function may be used to provide feedback about the progress
45 of the key generation. If cb is not NULL, it will be called as follows
46 using the BN_GENCB_call() function described on the
47 BN_generate_prime(3) page.
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49 RSA_generate_prime() is similar to RSA_generate_prime_ex() but expects
50 an old-style callback function; see BN_generate_prime(3) for
51 information on the old-style callback.
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53 · While a random prime number is generated, it is called as described
54 in BN_generate_prime(3).
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56 · When the n-th randomly generated prime is rejected as not suitable
57 for the key, BN_GENCB_call(cb, 2, n) is called.
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59 · When a random p has been found with p-1 relatively prime to e, it is
60 called as BN_GENCB_call(cb, 3, 0).
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62 The process is then repeated for prime q and other primes (if any) with
63 BN_GENCB_call(cb, 3, i) where i indicates the i-th prime.
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66 RSA_generate_multi_prime_key() returns 1 on success or 0 on error.
67 RSA_generate_key_ex() returns 1 on success or 0 on error. The error
68 codes can be obtained by ERR_get_error(3).
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70 RSA_generate_key() returns a pointer to the RSA structure or NULL if
71 the key generation fails.
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74 BN_GENCB_call(cb, 2, x) is used with two different meanings.
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77 ERR_get_error(3), RAND_bytes(3), BN_generate_prime(3)
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80 RSA_generate_key() was deprecated in OpenSSL 0.9.8; use
81 RSA_generate_key_ex() instead.
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84 Copyright 2000-2018 The OpenSSL Project Authors. All Rights Reserved.
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86 Licensed under the OpenSSL license (the "License"). You may not use
87 this file except in compliance with the License. You can obtain a copy
88 in the file LICENSE in the source distribution or at
89 <https://www.openssl.org/source/license.html>.
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931.1.1c 2019-05-28 RSA_GENERATE_KEY(3)