SYNOPSIS

#include <openssl/evp.h>
EVP_PKEY_CTX *EVP_PKEY_CTX_new(EVP_PKEY *pkey, ENGINE *e);
EVP_PKEY_CTX *EVP_PKEY_CTX_new_id(int id, ENGINE *e);
EVP_PKEY_CTX *EVP_PKEY_CTX_dup(EVP_PKEY_CTX *ctx);
void EVP_PKEY_CTX_free(EVP_PKEY_CTX *ctx);

DESCRIPTION

The EVP_PKEY_CTX_new() function allocates public key algorithm context using the algorithm specified in pkey and ENGINE e.

The EVP_PKEY_CTX_new_id() function allocates public key algorithm context using the algorithm specified by id and ENGINE e. It is normally used when no EVP_PKEY structure is associated with the operations, for example during parameter generation of key genration for some algorithms.

EVP_PKEY_CTX_dup() duplicates the context ctx.

EVP_PKEY_CTX_free() frees up the context ctx.

NOTES

The EVP_PKEY_CTX structure is an opaque public key algorithm context used by the OpenSSL high level public key API. Contexts MUST NOT be shared between threads: that is it is not permissible to use the same context simultaneously in two threads.

RETURN VALUES

EVP_PKEY_CTX_new(), EVP_PKEY_CTX_new_id(), EVP_PKEY_CTX_dup() returns either the newly allocated EVP_PKEY_CTX structure of NULL if an error occurred.

EVP_PKEY_CTX_free() does not return a value.

HISTORY

These functions were first added to OpenSSL 1.0.0.