mirror of
https://github.com/openssl/openssl.git
synced 2024-12-09 05:51:54 +08:00
3c86a2b5c8
Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/10420)
(cherry picked from commit ca7c982821)
189 lines
7.2 KiB
Plaintext
189 lines
7.2 KiB
Plaintext
=pod
|
|
|
|
=head1 NAME
|
|
|
|
EVP_DigestVerifyInit_ex, EVP_DigestVerifyInit, EVP_DigestVerifyUpdate,
|
|
EVP_DigestVerifyFinal, EVP_DigestVerify - EVP signature verification functions
|
|
|
|
=head1 SYNOPSIS
|
|
|
|
#include <openssl/evp.h>
|
|
|
|
int EVP_DigestVerifyInit_ex(EVP_MD_CTX *ctx, EVP_PKEY_CTX **pctx,
|
|
const char *mdname, const char *props,
|
|
EVP_PKEY *pkey, EVP_SIGNATURE *signature);
|
|
int EVP_DigestVerifyInit(EVP_MD_CTX *ctx, EVP_PKEY_CTX **pctx,
|
|
const EVP_MD *type, ENGINE *e, EVP_PKEY *pkey);
|
|
int EVP_DigestVerifyUpdate(EVP_MD_CTX *ctx, const void *d, size_t cnt);
|
|
int EVP_DigestVerifyFinal(EVP_MD_CTX *ctx, const unsigned char *sig,
|
|
size_t siglen);
|
|
int EVP_DigestVerify(EVP_MD_CTX *ctx, const unsigned char *sigret,
|
|
size_t siglen, const unsigned char *tbs, size_t tbslen);
|
|
|
|
=head1 DESCRIPTION
|
|
|
|
The EVP signature routines are a high level interface to digital signatures.
|
|
Input data is digested first before the signature verification takes place.
|
|
|
|
EVP_DigestVerifyInit_ex() sets up verification context B<ctx> to use a digest
|
|
with the name B<mdname> and public key B<pkey>. The signature algorithm
|
|
B<signature> will be used for the actual signature verification which must be
|
|
compatible with the public key. The name of the digest to be used is passed to
|
|
the provider of the signature algorithm in use. How that provider interprets the
|
|
digest name is provider specific. The provider may implement that digest
|
|
directly itself or it may (optionally) choose to fetch it (which could result in
|
|
a digest from a different provider being selected). If the provider supports
|
|
fetching the digest then it may use the B<props> argument for the properties to
|
|
be used during the fetch.
|
|
|
|
The B<signature> parameter may be NULL in which case a suitable signature
|
|
algorithm implementation will be implicitly fetched based on the type of key in
|
|
use. See L<provider(7)> for further information about providers and fetching
|
|
algorithms.
|
|
|
|
The OpenSSL default and legacy providers support fetching digests and can fetch
|
|
those digests from any available provider. The OpenSSL fips provider also
|
|
supports fetching digests but will only fetch digests that are themselves
|
|
implemented inside the fips provider.
|
|
|
|
B<ctx> must be created with EVP_MD_CTX_new() before calling this function. If
|
|
B<pctx> is not NULL, the EVP_PKEY_CTX of the verification operation will be
|
|
written to B<*pctx>: this can be used to set alternative verification options.
|
|
Note that any existing value in B<*pctx> is overwritten. The EVP_PKEY_CTX value
|
|
returned must not be freed directly by the application if B<ctx> is not assigned
|
|
an EVP_PKEY_CTX value before being passed to EVP_DigestVerifyInit_ex() (which
|
|
means the EVP_PKEY_CTX is created inside EVP_DigestVerifyInit_ex() and it will
|
|
be freed automatically when the EVP_MD_CTX is freed).
|
|
|
|
No B<EVP_PKEY_CTX> will be created by EVP_DigestSignInit_ex() if the passed
|
|
B<ctx> has already been assigned one via L<EVP_MD_CTX_set_pkey_ctx(3)>. See also
|
|
L<SM2(7)>.
|
|
|
|
Not all digests can be used for all key types. The following combinations apply.
|
|
|
|
=over 4
|
|
|
|
=item DSA
|
|
|
|
Supports SHA1, SHA224, SHA256, SHA384 and SHA512
|
|
|
|
=item ECDSA
|
|
|
|
Supports SHA1, SHA224, SHA256, SHA384, SHA512 and SM3
|
|
|
|
=item RSA with no padding
|
|
|
|
Supports no digests (the digest B<type> must be NULL)
|
|
|
|
=item RSA with X931 padding
|
|
|
|
Supports SHA1, SHA256, SHA384 and SHA512
|
|
|
|
=item All other RSA padding types
|
|
|
|
Support SHA1, SHA224, SHA256, SHA384, SHA512, MD5, MD5_SHA1, MD2, MD4, MDC2,
|
|
SHA3-224, SHA3-256, SHA3-384, SHA3-512
|
|
|
|
=item Ed25519 and Ed448
|
|
|
|
Support no digests (the digest B<type> must be NULL)
|
|
|
|
=item HMAC
|
|
|
|
Supports any digest
|
|
|
|
=item CMAC, Poly1305 and SipHash
|
|
|
|
Will ignore any digest provided.
|
|
|
|
=back
|
|
|
|
If RSA-PSS is used and restrictions apply then the digest must match.
|
|
|
|
EVP_DigestVerifyInit() works in the same way as EVP_DigestVerifyInit_ex() except
|
|
that the B<mdname> parameter will be inferred from the supplied digest B<type>,
|
|
and B<props> will be NULL. Where supplied the ENGINE B<e> will be used for the
|
|
signature verification and digest algorithm implementations. B<e> may be NULL.
|
|
|
|
EVP_DigestVerifyUpdate() hashes B<cnt> bytes of data at B<d> into the
|
|
verification context B<ctx>. This function can be called several times on the
|
|
same B<ctx> to include additional data.
|
|
|
|
EVP_DigestVerifyFinal() verifies the data in B<ctx> against the signature in
|
|
B<sig> of length B<siglen>.
|
|
|
|
EVP_DigestVerify() verifies B<tbslen> bytes at B<tbs> against the signature
|
|
in B<sig> of length B<siglen>.
|
|
|
|
=head1 RETURN VALUES
|
|
|
|
EVP_DigestVerifyInit() and EVP_DigestVerifyUpdate() return 1 for success and 0
|
|
for failure.
|
|
|
|
EVP_DigestVerifyFinal() and EVP_DigestVerify() return 1 for success; any other
|
|
value indicates failure. A return value of zero indicates that the signature
|
|
did not verify successfully (that is, B<tbs> did not match the original data or
|
|
the signature had an invalid form), while other values indicate a more serious
|
|
error (and sometimes also indicate an invalid signature form).
|
|
|
|
The error codes can be obtained from L<ERR_get_error(3)>.
|
|
|
|
=head1 NOTES
|
|
|
|
The B<EVP> interface to digital signatures should almost always be used in
|
|
preference to the low level interfaces. This is because the code then becomes
|
|
transparent to the algorithm used and much more flexible.
|
|
|
|
EVP_DigestVerify() is a one shot operation which verifies a single block of
|
|
data in one function. For algorithms that support streaming it is equivalent
|
|
to calling EVP_DigestVerifyUpdate() and EVP_DigestVerifyFinal(). For
|
|
algorithms which do not support streaming (e.g. PureEdDSA) it is the only way
|
|
to verify data.
|
|
|
|
In previous versions of OpenSSL there was a link between message digest types
|
|
and public key algorithms. This meant that "clone" digests such as EVP_dss1()
|
|
needed to be used to sign using SHA1 and DSA. This is no longer necessary and
|
|
the use of clone digest is now discouraged.
|
|
|
|
For some key types and parameters the random number generator must be seeded.
|
|
If the automatic seeding or reseeding of the OpenSSL CSPRNG fails due to
|
|
external circumstances (see L<RAND(7)>), the operation will fail.
|
|
|
|
The call to EVP_DigestVerifyFinal() internally finalizes a copy of the digest
|
|
context. This means that EVP_VerifyUpdate() and EVP_VerifyFinal() can
|
|
be called later to digest and verify additional data.
|
|
|
|
Since only a copy of the digest context is ever finalized, the context must
|
|
be cleaned up after use by calling EVP_MD_CTX_free() or a memory leak
|
|
will occur.
|
|
|
|
=head1 SEE ALSO
|
|
|
|
L<EVP_DigestSignInit(3)>,
|
|
L<EVP_DigestInit(3)>,
|
|
L<evp(7)>, L<HMAC(3)>, L<MD2(3)>,
|
|
L<MD5(3)>, L<MDC2(3)>, L<RIPEMD160(3)>,
|
|
L<SHA1(3)>, L<openssl-dgst(1)>,
|
|
L<RAND(7)>
|
|
|
|
=head1 HISTORY
|
|
|
|
EVP_DigestVerifyInit(), EVP_DigestVerifyUpdate() and EVP_DigestVerifyFinal()
|
|
were added in OpenSSL 1.0.0.
|
|
|
|
EVP_DigestVerifyInit_ex() was added in OpenSSL 3.0.
|
|
|
|
EVP_DigestVerifyUpdate() was converted from a macro to a function in OpenSSL
|
|
3.0.
|
|
|
|
=head1 COPYRIGHT
|
|
|
|
Copyright 2006-2018 The OpenSSL Project Authors. All Rights Reserved.
|
|
|
|
Licensed under the Apache License 2.0 (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
|