libressl-X509_NAME_hash(3)

libressl-X509_NAME_hash3

Calculate sha-1 or md5 hashes of x.501 name objects

Usage

Crypto Library (libcrypto, -lcrypto)

#include <openssl/x509.h>

unsigned long

X509_NAME_hash(X509_NAME *name);

unsigned long

X509_issuer_name_hash(X509 *x);

unsigned long

X509_subject_name_hash(X509 *x);

unsigned long

X509_NAME_hash_old(X509_NAME *name);

unsigned long

X509_issuer_name_hash_old(X509 *x);

unsigned long

X509_subject_name_hash_old(X509 *x);

Overview

X509_NAME_hash() calculates an SHA1(3) hash of the DER-encoded form of name. It is for example used by X509_LOOKUP_hash_dir(3) to locate certificate files in the file system.

X509_issuer_name_hash() and X509_subject_name_hash() are wrappers to calculate this hash of the issuer or subject name of x, respectively.

X509_NAME_hash_old(), X509_issuer_name_hash_old(), and X509_subject_name_hash_old() are variants that use MD5 instead of SHA-1.

Return values

These functions return the hash value or 0 if an error occurs.

History

X509_subject_name_hash() first appeared in SSLeay 0.4.0, X509_issuer_name_hash() in SSLeay 0.5.1, and X509_NAME_hash() in SSLeay 0.8.0. They were switched to hashing the DER representation of the name rather than an ASCII rendering in SSLeay 0.9.0 and have all been available since OpenBSD 2.4.

They were switched to using SHA-1 instead of MD5 in OpenSSL 1.0.0 and in OpenBSD 4.9.

X509_NAME_hash_old(), X509_issuer_name_hash_old(), and X509_subject_name_hash_old() first appeared in OpenSSL 1.0.0 and have been available since OpenBSD 4.9.

From libressl 4.4.0-1 in Arch Linux 2026-11-01. Parsed by carta from the page's mdoc source.