- NAME
- SYNOPSIS
- DESCRIPTION
- NOTES
- RETURN VALUES
- SEE ALSO
- HISTORY

# NAME

EVP_PKEY_get_default_digest_nid - get default signature digest

# SYNOPSIS

     #include <openssl/evp.h>
     int EVP_PKEY_get_default_digest_nid(EVP_PKEY *pkey, int *pnid);

# DESCRIPTION

The `EVP_PKEY_get_default_digest_nid()` function sets pnid to the default message digest NID for the public key signature operations associated with key pkey.

# NOTES

For all current standard OpenSSL public key algorithms SHA1 is returned.

# RETURN VALUES

The `EVP_PKEY_get_default_digest_nid()` function returns 1 if the message digest is advisory (that is other digests can be used) and 2 if it is mandatory (other digests can not be used). It returns 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, EVP_PKEY_sign, EVP_PKEY_verify, EVP_PKEY_verify_recover,

# HISTORY

This function was first added to OpenSSL 1.0.0.