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RSA_check_key(3) OpenSSL RSA_check_key(3)
NNAAMMEE
RSA_check_key - validate private RSA keys
SSYYNNOOPPSSIISS
#include
int RSA_check_key(RSA *rsa);
DDEESSCCRRIIPPTTIIOONN
This function validates RSA keys. It checks that pp and qq are in fact
prime, and that nn == pp**qq.
It also checks that dd**ee == 11 mmoodd ((pp--11**qq--11)), and that ddmmpp11, ddmmqq11 and iiqqmmpp
are set correctly or are NNUULLLL.
As such, this function can not be used with any arbitrary RSA key
object, even if it is otherwise fit for regular RSA operation. See
NNOOTTEESS for more information.
RREETTUURRNN VVAALLUUEE
_R_S_A___c_h_e_c_k___k_e_y_(_) returns 1 if rrssaa is a valid RSA key, and 0 otherwise.
-1 is returned if an error occurs while checking the key.
If the key is invalid or an error occurred, the reason code can be
obtained using _E_R_R___g_e_t___e_r_r_o_r(3).
NNOOTTEESS
This function does not work on RSA public keys that have only the modu-
lus and public exponent elements populated. It performs integrity
checks on all the RSA key material, so the RSA key structure must con-
tain all the private key data too.
Unlike most other RSA functions, this function does nnoott work transpar-
ently with any underlying ENGINE implementation because it uses the key
data in the RSA structure directly. An ENGINE implementation can over-
ride the way key data is stored and handled, and can even provide sup-
port for HSM keys - in which case the RSA structure may contain nnoo key
data at all! If the ENGINE in question is only being used for accelera-
tion or analysis purposes, then in all likelihood the RSA key data is
complete and untouched, but this can't be assumed in the general case.
BBUUGGSS
A method of verifying the RSA key using opaque RSA API functions might
need to be considered. Right now _R_S_A___c_h_e_c_k___k_e_y_(_) simply uses the RSA
structure elements directly, bypassing the RSA_METHOD table altogether
(and completely violating encapsulation and object-orientation in the
process). The best fix will probably be to introduce a "_c_h_e_c_k___k_e_y_(_)"
handler to the RSA_METHOD function table so that alternative implemen-
tations can also provide their own verifiers.
SSEEEE AALLSSOO
_r_s_a(3), _E_R_R___g_e_t___e_r_r_o_r(3)
HHIISSTTOORRYY
_R_S_A___c_h_e_c_k___k_e_y_(_) appeared in OpenSSL 0.9.4.
1.0.2t 2019-09-10 RSA_check_key(3)