EVP_PKEY_PRINT_PRIVATE(3) | Library Functions Manual | EVP_PKEY_PRINT_PRIVATE(3)

# NAME

`EVP_PKEY_print_public`, `EVP_PKEY_print_private`, `EVP_PKEY_print_params` — public key algorithm printing routines

# SYNOPSIS

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

int
`EVP_PKEY_print_public`(BIO *out, const EVP_PKEY *pkey, int indent, ASN1_PCTX *pctx);

int
`EVP_PKEY_print_private`(BIO *out, const EVP_PKEY *pkey, int indent, ASN1_PCTX *pctx);

int
`EVP_PKEY_print_params`(BIO *out, const EVP_PKEY *pkey, int indent, ASN1_PCTX *pctx);

# DESCRIPTION

The functions `EVP_PKEY_print_public`(), `EVP_PKEY_print_private`(), and `EVP_PKEY_print_params`() print out the public, private or parameter components of key pkey, respectively. The key is sent to BIO out in human readable form. The parameter indent indicates how far the printout should be indented.

The pctx parameter allows the print output to be finely tuned by using ASN.1 printing options. If pctx is set to `NULL`, then default values will be used. Currently, no public key algorithms include any options in the pctx parameter.

If the key does not include all the components indicated by the function, then only those contained in the key will be printed. For example, passing a public key to `EVP_PKEY_print_private`() will only print the public components.

# RETURN VALUES

These functions all return 1 for success and 0 or a negative value for failure. In particular, a return value of -2 indicates the operation is not supported by the public key algorithm.

# SEE ALSO

EVP_PKEY_CTX_new(3), EVP_PKEY_keygen(3), EVP_PKEY_new(3)

# HISTORY

These functions first appeared in OpenSSL 1.0.0 and have been available since OpenBSD 4.9.

June 8, 2025 | Debian