mirror of
https://github.com/openssl/openssl.git
synced 2024-11-21 01:15:20 +08:00
9b86974e0c
L<foo|foo> is sub-optimal If the xref is the same as the title, which is what we do, then you only need L<foo>. This fixes all 1457 occurrences in 349 files. Approximately. (And pod used to need both.) Reviewed-by: Richard Levitte <levitte@openssl.org>
92 lines
2.6 KiB
Plaintext
92 lines
2.6 KiB
Plaintext
=pod
|
|
|
|
=head1 NAME
|
|
|
|
EVP_PKEY_verify_init, EVP_PKEY_verify - signature verification using a public key algorithm
|
|
|
|
=head1 SYNOPSIS
|
|
|
|
#include <openssl/evp.h>
|
|
|
|
int EVP_PKEY_verify_init(EVP_PKEY_CTX *ctx);
|
|
int EVP_PKEY_verify(EVP_PKEY_CTX *ctx,
|
|
const unsigned char *sig, size_t siglen,
|
|
const unsigned char *tbs, size_t tbslen);
|
|
|
|
=head1 DESCRIPTION
|
|
|
|
The EVP_PKEY_verify_init() function initializes a public key algorithm
|
|
context using key B<pkey> for a signature verification operation.
|
|
|
|
The EVP_PKEY_verify() function performs a public key verification operation
|
|
using B<ctx>. The signature is specified using the B<sig> and
|
|
B<siglen> parameters. The verified data (i.e. the data believed originally
|
|
signed) is specified using the B<tbs> and B<tbslen> parameters.
|
|
|
|
=head1 NOTES
|
|
|
|
After the call to EVP_PKEY_verify_init() algorithm specific control
|
|
operations can be performed to set any appropriate parameters for the
|
|
operation.
|
|
|
|
The function EVP_PKEY_verify() can be called more than once on the same
|
|
context if several operations are performed using the same parameters.
|
|
|
|
=head1 RETURN VALUES
|
|
|
|
EVP_PKEY_verify_init() and EVP_PKEY_verify() return 1 if the verification was
|
|
successful and 0 if it failed. Unlike other functions the return value 0 from
|
|
EVP_PKEY_verify() only indicates that the signature did not not verify
|
|
successfully (that is tbs did not match the original data or the signature was
|
|
of invalid form) it is not an indication of a more serious error.
|
|
|
|
A negative value indicates an error other that signature verification failure.
|
|
In particular a return value of -2 indicates the operation is not supported by
|
|
the public key algorithm.
|
|
|
|
=head1 EXAMPLE
|
|
|
|
Verify signature using PKCS#1 and SHA256 digest:
|
|
|
|
#include <openssl/evp.h>
|
|
#include <openssl/rsa.h>
|
|
|
|
EVP_PKEY_CTX *ctx;
|
|
unsigned char *md, *sig;
|
|
size_t mdlen, siglen;
|
|
EVP_PKEY *verify_key;
|
|
/* NB: assumes verify_key, sig, siglen md and mdlen are already set up
|
|
* and that verify_key is an RSA public key
|
|
*/
|
|
ctx = EVP_PKEY_CTX_new(verify_key);
|
|
if (!ctx)
|
|
/* Error occurred */
|
|
if (EVP_PKEY_verify_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 */
|
|
|
|
/* Perform operation */
|
|
ret = EVP_PKEY_verify(ctx, sig, siglen, md, mdlen);
|
|
|
|
/* ret == 1 indicates success, 0 verify failure and < 0 for some
|
|
* other error.
|
|
*/
|
|
|
|
=head1 SEE ALSO
|
|
|
|
L<EVP_PKEY_CTX_new(3)>,
|
|
L<EVP_PKEY_encrypt(3)>,
|
|
L<EVP_PKEY_decrypt(3)>,
|
|
L<EVP_PKEY_sign(3)>,
|
|
L<EVP_PKEY_verify_recover(3)>,
|
|
L<EVP_PKEY_derive(3)>
|
|
|
|
=head1 HISTORY
|
|
|
|
These functions were first added to OpenSSL 1.0.0.
|
|
|
|
=cut
|