-.\" $OpenBSD: SHA1.3,v 1.8 2024/05/26 09:54:16 tb Exp $
+.\" $OpenBSD: SHA1.3,v 1.9 2024/06/01 12:35:23 tb Exp $
.\" OpenSSL 99d63d46 Oct 26 13:56:48 2016 -0400
.\"
.\" This file was written by Ulf Moeller <ulf@openssl.org> and
.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
.\" OF THE POSSIBILITY OF SUCH DAMAGE.
.\"
-.Dd $Mdocdate: May 26 2024 $
+.Dd $Mdocdate: June 1 2024 $
.Dt SHA1 3
.Os
.Sh NAME
Applications should use the higher level functions
.Xr EVP_DigestInit 3
etc. instead of calling the hash functions directly.
-.Pp
-The predecessor of SHA-1, SHA, is also implemented, but it should be
-used only when backward compatibility is required.
.Sh RETURN VALUES
.Fn SHA1 ,
.Fn SHA224 ,
.Xr HMAC 3 ,
.Xr RIPEMD160 3
.Sh STANDARDS
-SHA: US Federal Information Processing Standard FIPS PUB 180 (Secure
-Hash Standard), SHA-1: US Federal Information Processing Standard FIPS
-PUB 180-1 (Secure Hash Standard), ANSI X9.30
+.Rs
+.%T Secure Hash Standard (SHS)
+.%R NIST FIPS Publication
+.%N 180-4
+.%U https://doi.org/10.6028/NIST.FIPS.180-4
+.%D 2015
+.Re
.Sh HISTORY
.Fn SHA1 ,
.Fn SHA1_Init ,