D2I_DHPARAMS(3) | Library Functions Manual | D2I_DHPARAMS(3)

# NAME

`d2i_DHparams`, `i2d_DHparams` — PKCS#3 DH parameter functions

# SYNOPSIS

library “libcrypto”
`#include <openssl/dh.h>`

DH *
`d2i_DHparams`(DH **a, unsigned char **pp, long length);

int
`i2d_DHparams`(DH *a, unsigned char **pp);

# DESCRIPTION

These functions decode and encode PKCS#3 DH parameters using the DHparameter structure described in PKCS#3. They otherwise behave in a way similar to d2i_X509(3) and i2d_X509(3).

# RETURN VALUES

`d2i_DHparams`() returns a DH object or `NULL` if an error occurs.

`i2d_DHparams`() returns the number of bytes successfully encoded or a value <= 0 if an error occurs.

# SEE ALSO

d2i_X509(3), DH_new(3)

# HISTORY

`d2i_DHparams`() and `i2d_DHparams`() first appeared in SSLeay 0.5.1 and have been available since OpenBSD 2.4.

June 8, 2025 | Debian