+++ /dev/null
-=pod
-
-=head1 NAME
-
-CMS_verify, CMS_get0_signers - verify a CMS SignedData structure
-
-=head1 SYNOPSIS
-
- #include <openssl/cms.h>
-
- int CMS_verify(CMS_ContentInfo *cms, STACK_OF(X509) *certs, X509_STORE *store, BIO *indata, BIO *out, unsigned int flags);
-
- STACK_OF(X509) *CMS_get0_signers(CMS_ContentInfo *cms);
-
-=head1 DESCRIPTION
-
-CMS_verify() verifies a CMS SignedData structure. B<cms> is the CMS_ContentInfo
-structure to verify. B<certs> is a set of certificates in which to search for
-the signing certificate(s). B<store> is a trusted certificate store used for
-chain verification. B<indata> is the detached content if the content is not
-present in B<cms>. The content is written to B<out> if it is not NULL.
-
-B<flags> is an optional set of flags, which can be used to modify the verify
-operation.
-
-CMS_get0_signers() retrieves the signing certificate(s) from B<cms>, it must
-be called after a successful CMS_verify() operation.
-
-=head1 VERIFY PROCESS
-
-Normally the verify process proceeds as follows.
-
-Initially some sanity checks are performed on B<cms>. The type of B<cms> must
-be SignedData. There must be at least one signature on the data and if
-the content is detached B<indata> cannot be B<NULL>.
-
-An attempt is made to locate all the signing certificate(s), first looking in
-the B<certs> parameter (if it is not NULL) and then looking in any
-certificates contained in the B<cms> structure itself. If any signing
-certificate cannot be located the operation fails.
-
-Each signing certificate is chain verified using the B<smimesign> purpose and
-the supplied trusted certificate store. Any internal certificates in the message
-are used as untrusted CAs. If CRL checking is enabled in B<store> any internal
-CRLs are used in addition to attempting to look them up in B<store>. If any
-chain verify fails an error code is returned.
-
-Finally the signed content is read (and written to B<out> is it is not NULL)
-and the signature's checked.
-
-If all signature's verify correctly then the function is successful.
-
-Any of the following flags (ored together) can be passed in the B<flags>
-parameter to change the default verify behaviour.
-
-If B<CMS_NOINTERN> is set the certificates in the message itself are not
-searched when locating the signing certificate(s). This means that all the
-signing certificates must be in the B<certs> parameter.
-
-If B<CMS_NOCRL> is set and CRL checking is enabled in B<store> then any
-CRLs in the message itself are ignored.
-
-If the B<CMS_TEXT> flag is set MIME headers for type B<text/plain> are deleted
-from the content. If the content is not of type B<text/plain> then an error is
-returned.
-
-If B<CMS_NO_SIGNER_CERT_VERIFY> is set the signing certificates are not
-verified.
-
-If B<CMS_NO_ATTR_VERIFY> is set the signed attributes signature is not
-verified.
-
-If B<CMS_NO_CONTENT_VERIFY> is set then the content digest is not checked.
-
-=head1 NOTES
-
-One application of B<CMS_NOINTERN> is to only accept messages signed by
-a small number of certificates. The acceptable certificates would be passed
-in the B<certs> parameter. In this case if the signer is not one of the
-certificates supplied in B<certs> then the verify will fail because the
-signer cannot be found.
-
-In some cases the standard techniques for looking up and validating
-certificates are not appropriate: for example an application may wish to
-lookup certificates in a database or perform customised verification. This
-can be achieved by setting and verifying the signers certificates manually
-using the signed data utility functions.
-
-Care should be taken when modifying the default verify behaviour, for example
-setting B<CMS_NO_CONTENT_VERIFY> will totally disable all content verification
-and any modified content will be considered valid. This combination is however
-useful if one merely wishes to write the content to B<out> and its validity
-is not considered important.
-
-Chain verification should arguably be performed using the signing time rather
-than the current time. However since the signing time is supplied by the
-signer it cannot be trusted without additional evidence (such as a trusted
-timestamp).
-
-=head1 RETURN VALUES
-
-CMS_verify() returns 1 for a successful verification and zero if an error
-occurred.
-
-CMS_get0_signers() returns all signers or NULL if an error occurred.
-
-The error can be obtained from L<ERR_get_error(3)>
-
-=head1 BUGS
-
-The trusted certificate store is not searched for the signing certificate,
-this is primarily due to the inadequacies of the current B<X509_STORE>
-functionality.
-
-The lack of single pass processing means that the signed content must all
-be held in memory if it is not detached.
-
-=head1 SEE ALSO
-
-L<ERR_get_error(3)>, L<CMS_sign(3)>
-
-=head1 COPYRIGHT
-
-Copyright 2008-2016 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