1=pod 2 3=head1 NAME 4 5EVP_sha1 6- SHA-1 For EVP 7 8=head1 SYNOPSIS 9 10 #include <openssl/evp.h> 11 12 const EVP_MD *EVP_sha1(void); 13 14=head1 DESCRIPTION 15 16SHA-1 (Secure Hash Algorithm 1) is a cryptographic hash function standardized 17in NIST FIPS 180-4. The algorithm was designed by the United States National 18Security Agency and initially published in 1995. 19 20=over 4 21 22=item EVP_sha1() 23 24The SHA-1 algorithm which produces a 160-bit output from a given input. 25 26=back 27 28=head1 NOTES 29 30Developers should be aware of the negative performance implications of 31calling this function multiple times and should consider using 32L<EVP_MD_fetch(3)> with L<EVP_MD-SHA1(7)> instead. 33See L<crypto(7)/Performance> for further information. 34 35=head1 RETURN VALUES 36 37These functions return a B<EVP_MD> structure that contains the 38implementation of the message digest. See L<EVP_MD_meth_new(3)> for 39details of the B<EVP_MD> structure. 40 41=head1 CONFORMING TO 42 43NIST FIPS 180-4. 44 45=head1 SEE ALSO 46 47L<evp(7)>, 48L<EVP_DigestInit(3)> 49 50=head1 COPYRIGHT 51 52Copyright 2017-2023 The OpenSSL Project Authors. All Rights Reserved. 53 54Licensed under the Apache License 2.0 (the "License"). You may not use 55this file except in compliance with the License. You can obtain a copy 56in the file LICENSE in the source distribution or at 57L<https://www.openssl.org/source/license.html>. 58 59=cut 60 61