1=pod 2 3=head1 NAME 4 5RSA_check_key_ex, RSA_check_key - validate private RSA keys 6 7=head1 SYNOPSIS 8 9 #include <openssl/rsa.h> 10 11The following functions have been deprecated since OpenSSL 3.0, and can be 12hidden entirely by defining B<OPENSSL_API_COMPAT> with a suitable version value, 13see L<openssl_user_macros(7)>: 14 15 int RSA_check_key_ex(const RSA *rsa, BN_GENCB *cb); 16 17 int RSA_check_key(const RSA *rsa); 18 19=head1 DESCRIPTION 20 21Both of the functions described on this page are deprecated. 22Applications should instead use L<EVP_PKEY_public_check(3)>, 23L<EVP_PKEY_private_check(3)> and L<EVP_PKEY_pairwise_check(3)>. 24 25RSA_check_key_ex() function validates RSA keys. 26It checks that B<p> and B<q> are 27in fact prime, and that B<n = p*q>. 28 29It does not work on RSA public keys that have only the modulus 30and public exponent elements populated. 31It also checks that B<d*e = 1 mod (p-1*q-1)>, 32and that B<dmp1>, B<dmq1> and B<iqmp> are set correctly or are B<NULL>. 33It performs integrity checks on all 34the RSA key material, so the RSA key structure must contain all the private 35key data too. 36Therefore, it cannot be used with any arbitrary RSA key object, 37even if it is otherwise fit for regular RSA operation. 38 39The B<cb> parameter is a callback that will be invoked in the same 40manner as L<BN_is_prime_ex(3)>. 41 42RSA_check_key() is equivalent to RSA_check_key_ex() with a NULL B<cb>. 43 44=head1 RETURN VALUES 45 46RSA_check_key_ex() and RSA_check_key() 47return 1 if B<rsa> is a valid RSA key, and 0 otherwise. 48They return -1 if an error occurs while checking the key. 49 50If the key is invalid or an error occurred, the reason code can be 51obtained using L<ERR_get_error(3)>. 52 53=head1 NOTES 54 55Unlike most other RSA functions, this function does B<not> work 56transparently with any underlying ENGINE implementation because it uses the 57key data in the RSA structure directly. An ENGINE implementation can 58override the way key data is stored and handled, and can even provide 59support for HSM keys - in which case the RSA structure may contain B<no> 60key data at all! If the ENGINE in question is only being used for 61acceleration or analysis purposes, then in all likelihood the RSA key data 62is complete and untouched, but this can't be assumed in the general case. 63 64=head1 BUGS 65 66A method of verifying the RSA key using opaque RSA API functions might need 67to be considered. Right now RSA_check_key() simply uses the RSA structure 68elements directly, bypassing the RSA_METHOD table altogether (and 69completely violating encapsulation and object-orientation in the process). 70The best fix will probably be to introduce a "check_key()" handler to the 71RSA_METHOD function table so that alternative implementations can also 72provide their own verifiers. 73 74=head1 SEE ALSO 75 76L<BN_is_prime_ex(3)>, 77L<ERR_get_error(3)> 78 79=head1 HISTORY 80 81All of these functions were deprecated in OpenSSL 3.0. 82 83RSA_check_key_ex() appeared after OpenSSL 1.0.2. 84 85=head1 COPYRIGHT 86 87Copyright 2000-2020 The OpenSSL Project Authors. All Rights Reserved. 88 89Licensed under the Apache License 2.0 (the "License"). You may not use 90this file except in compliance with the License. You can obtain a copy 91in the file LICENSE in the source distribution or at 92L<https://www.openssl.org/source/license.html>. 93 94=cut 95
