+++ /dev/null
-=pod
-
-=head1 NAME
-
-EVP_PKEY_sign_init, EVP_PKEY_sign - sign using a public key algorithm
-
-=head1 SYNOPSIS
-
- #include <openssl/evp.h>
-
- int EVP_PKEY_sign_init(EVP_PKEY_CTX *ctx);
- int EVP_PKEY_sign(EVP_PKEY_CTX *ctx,
- unsigned char *sig, size_t *siglen,
- const unsigned char *tbs, size_t tbslen);
-
-=head1 DESCRIPTION
-
-The EVP_PKEY_sign_init() function initializes a public key algorithm
-context using key B<pkey> for a signing operation.
-
-The EVP_PKEY_sign() function performs a public key signing operation
-using B<ctx>. The data to be signed is specified using the B<tbs> and
-B<tbslen> parameters. If B<sig> is B<NULL> then the maximum size of the output
-buffer is written to the B<siglen> parameter. If B<sig> is not B<NULL> then
-before the call the B<siglen> parameter should contain the length of the
-B<sig> buffer, if the call is successful the signature is written to
-B<sig> and the amount of data written to B<siglen>.
-
-=head1 NOTES
-
-EVP_PKEY_sign() does not hash the data to be signed, and therefore is
-normally used to sign digests. For signing arbitrary messages, see the
-L<EVP_DigestSignInit(3)> and
-L<EVP_SignInit(3)> signing interfaces instead.
-
-After the call to EVP_PKEY_sign_init() algorithm specific control
-operations can be performed to set any appropriate parameters for the
-operation (see L<EVP_PKEY_CTX_ctrl(3)>).
-
-The function EVP_PKEY_sign() can be called more than once on the same
-context if several operations are performed using the same parameters.
-
-=head1 RETURN VALUES
-
-EVP_PKEY_sign_init() and EVP_PKEY_sign() 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.
-
-=head1 EXAMPLE
-
-Sign data using RSA with PKCS#1 padding and SHA256 digest:
-
- #include <openssl/evp.h>
- #include <openssl/rsa.h>
-
- EVP_PKEY_CTX *ctx;
- /* md is a SHA-256 digest in this example. */
- unsigned char *md, *sig;
- size_t mdlen = 32, siglen;
- EVP_PKEY *signing_key;
-
- /*
- * NB: assumes signing_key and md are set up before the next
- * step. signing_key must be an RSA private key and md must
- * point to the SHA-256 digest to be signed.
- */
- ctx = EVP_PKEY_CTX_new(signing_key, NULL /* no engine */);
- if (!ctx)
- /* Error occurred */
- if (EVP_PKEY_sign_init(ctx) <= 0)
- /* Error */
- if (EVP_PKEY_CTX_set_rsa_padding(ctx, RSA_PKCS1_PADDING) <= 0)
- /* Error */
- if (EVP_PKEY_CTX_set_signature_md(ctx, EVP_sha256()) <= 0)
- /* Error */
-
- /* Determine buffer length */
- if (EVP_PKEY_sign(ctx, NULL, &siglen, md, mdlen) <= 0)
- /* Error */
-
- sig = OPENSSL_malloc(siglen);
-
- if (!sig)
- /* malloc failure */
-
- if (EVP_PKEY_sign(ctx, sig, &siglen, md, mdlen) <= 0)
- /* Error */
-
- /* Signature is siglen bytes written to buffer sig */
-
-
-=head1 SEE ALSO
-
-L<EVP_PKEY_CTX_new(3)>,
-L<EVP_PKEY_CTX_ctrl(3)>,
-L<EVP_PKEY_encrypt(3)>,
-L<EVP_PKEY_decrypt(3)>,
-L<EVP_PKEY_verify(3)>,
-L<EVP_PKEY_verify_recover(3)>,
-L<EVP_PKEY_derive(3)>
-
-=head1 HISTORY
-
-These functions were first added to OpenSSL 1.0.0.
-
-=head1 COPYRIGHT
-
-Copyright 2006-2016 The OpenSSL Project Authors. All Rights Reserved.
-
-Licensed under the OpenSSL license (the "License"). You may not use
-this file except in compliance with the License. You can obtain a copy
-in the file LICENSE in the source distribution or at
-L<https://www.openssl.org/source/license.html>.
-
-=cut
projects / openssl.git / blobdiff