From b50ac7faef96a45291b0c3201b82185f7579e826 Mon Sep 17 00:00:00 2001 From: schwarze <> Date: Wed, 2 Nov 2016 09:11:53 +0000 Subject: convert DES and DH manuals from pod to mdoc --- src/lib/libcrypto/man/DH_generate_parameters.3 | 125 +++++++++++++++++++++++++ 1 file changed, 125 insertions(+) create mode 100644 src/lib/libcrypto/man/DH_generate_parameters.3 (limited to 'src/lib/libcrypto/man/DH_generate_parameters.3') diff --git a/src/lib/libcrypto/man/DH_generate_parameters.3 b/src/lib/libcrypto/man/DH_generate_parameters.3 new file mode 100644 index 0000000000..431ffd634c --- /dev/null +++ b/src/lib/libcrypto/man/DH_generate_parameters.3 @@ -0,0 +1,125 @@ +.Dd $Mdocdate: November 2 2016 $ +.Dt DH_GENERATE_PARAMETERS 3 +.Os +.Sh NAME +.Nm DH_generate_parameters_ex , +.Nm DH_generate_parameters , +.Nm DH_check +.Nd generate and check Diffie-Hellman parameters +.Sh SYNOPSIS +.In openssl/dh.h +.Ft int +.Fo DH_generate_parameters_ex +.Fa "DH *dh" +.Fa "int prime_len" +.Fa "int generator" +.Fa "BN_GENCB *cb" +.Fc +.Ft int +.Fo DH_check +.Fa "DH *dh" +.Fa "int *codes" +.Fc +.Pp +Deprecated: +.Pp +.Ft DH * +.Fo DH_generate_parameters +.Fa "int prime_len" +.Fa "int generator" +.Fa "void (*callback)(int" +.Fa int +.Fa "void *)" +.Fa "void *cb_arg" +.Fc +.Sh DESCRIPTION +.Fn DH_generate_parameters_ex +generates Diffie-Hellman parameters that can be shared among a group of +users, and stores them in the provided +.Vt DH +structure. +.Pp +.Fa prime_len +is the length in bits of the safe prime to be generated. +.Fa generator +is a small number > 1, typically 2 or 5. +.Pp +A callback function may be used to provide feedback about the progress +of the key generation. +If +.Fa cb +is not +.Dv NULL , +it will be called as described in +.Xr BN_generate_prime 3 +while a random prime number is generated, and when a prime has been +found, +.Fn BN_GENCB_call cb 3 0 +is called; see +.Xr BN_GENCB_call 3 . +.Pp +.Fn DH_check +validates Diffie-Hellman parameters. +It checks that +.Fa dh->p +is a safe prime, and that +.Fa dh->g +is a suitable generator. +In the case of an error, the bit flags +.Dv DH_CHECK_P_NOT_SAFE_PRIME +or +.Dv DH_NOT_SUITABLE_GENERATOR +are set in +.Pf * Fa codes . +.Dv DH_UNABLE_TO_CHECK_GENERATOR +is set if the generator cannot be checked, i.e. if it does not equal 2 or 5. +.Sh RETURN VALUES +.Fn DH_generate_parameters_ex +and +.Fn DH_check +return 1 if the check could be performed, 0 otherwise. +.Pp +.Fn DH_generate_parameters +(deprecated) returns a pointer to the +.Vt DH +structure, or +.Dv NULL +if the parameter generation fails. +.Pp +The error codes can be obtained by +.Xr ERR_get_error 3 . +.Sh SEE ALSO +.Xr dh 3 , +.Xr DH_free 3 , +.Xr ERR_get_error 3 , +.Xr rand 3 +.Sh HISTORY +.Fn DH_check +is available in all versions of SSLeay and OpenSSL. +The +.Fa cb_arg +argument to +.Fn DH_generate_parameters +was added in SSLeay 0.9.0. +.Pp +In versions before OpenSSL 0.9.5, +.Dv DH_CHECK_P_NOT_STRONG_PRIME +is used instead of +.Dv DH_CHECK_P_NOT_SAFE_PRIME . +.Sh CAVEATS +.Fn DH_generate_parameters_ex +and +.Fn DH_generate_parameters +may run for several hours before finding a suitable prime. +.Pp +The parameters generated by +.Fn DH_generate_parameters_ex +and +.Fn DH_generate_parameters +are not to be used in signature schemes. +.Sh BUGS +If +.Fa generator +is not 2 or 5, +.Fa dh->g Ns = Ns Fa generator +is not a usable generator. -- cgit v1.2.3-55-g6feb