Initial Commit

openssl-1.0.2f/doc/crypto/CMS_get0_SignerInfos.pod

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+=pod
+
+=head1 NAME
+
+CMS_get0_SignerInfos, CMS_SignerInfo_get0_signer_id, CMS_SignerInfo_get0_signature, CMS_SignerInfo_cert_cmp, CMS_set1_signer_cert - CMS signedData signer functions.
+
+=head1 SYNOPSIS
+
+ #include <openssl/cms.h>
+
+ STACK_OF(CMS_SignerInfo) *CMS_get0_SignerInfos(CMS_ContentInfo *cms);
+
+ int CMS_SignerInfo_get0_signer_id(CMS_SignerInfo *si, ASN1_OCTET_STRING **keyid, X509_NAME **issuer, ASN1_INTEGER **sno);
+ ASN1_OCTET_STRING *CMS_SignerInfo_get0_signature(CMS_SignerInfo *si);
+ int CMS_SignerInfo_cert_cmp(CMS_SignerInfo *si, X509 *cert);
+ void CMS_SignerInfo_set1_signer_cert(CMS_SignerInfo *si, X509 *signer);
+
+=head1 DESCRIPTION
+
+The function CMS_get0_SignerInfos() returns all the CMS_SignerInfo structures
+associated with a CMS signedData structure.
+
+CMS_SignerInfo_get0_signer_id() retrieves the certificate signer identifier
+associated with a specific CMS_SignerInfo structure B<si>. Either the
+keyidentifier will be set in B<keyid> or B<both> issuer name and serial number
+in B<issuer> and B<sno>.
+
+CMS_SignerInfo_get0_signature() retrieves the signature associated with 
+B<si> in a pointer to an ASN1_OCTET_STRING structure. This pointer returned
+corresponds to the internal signature value if B<si> so it may be read or
+modified.
+
+CMS_SignerInfo_cert_cmp() compares the certificate B<cert> against the signer
+identifier B<si>. It returns zero if the comparison is successful and non zero
+if not.
+
+CMS_SignerInfo_set1_signer_cert() sets the signers certificate of B<si> to
+B<signer>.
+
+=head1 NOTES
+
+The main purpose of these functions is to enable an application to lookup
+signers certificates using any appropriate technique when the simpler method
+of CMS_verify() is not appropriate.
+
+In typical usage and application will retrieve all CMS_SignerInfo structures
+using CMS_get0_SignerInfo() and retrieve the identifier information using
+CMS. It will then obtain the signer certificate by some unspecified means
+(or return and error if it cannot be found) and set it using
+CMS_SignerInfo_set1_signer_cert().
+
+Once all signer certificates have been set CMS_verify() can be used.
+
+Although CMS_get0_SignerInfos() can return NULL is an error occur B<or> if
+there are no signers this is not a problem in practice because the only
+error which can occur is if the B<cms> structure is not of type signedData
+due to application error.
+
+=head1 RETURN VALUES
+
+CMS_get0_SignerInfos() returns all CMS_SignerInfo structures, or NULL there
+are no signers or an error occurs.
+
+CMS_SignerInfo_get0_signer_id() returns 1 for success and 0 for failure.
+
+CMS_SignerInfo_cert_cmp() returns 0 for a successful comparison and non
+zero otherwise.
+
+CMS_SignerInfo_set1_signer_cert() does not return a value.
+
+Any error can be obtained from L<ERR_get_error(3)|ERR_get_error(3)>
+
+=head1 SEE ALSO
+
+L<ERR_get_error(3)|ERR_get_error(3)>, L<CMS_verify(3)|CMS_verify(3)>
+
+=head1 HISTORY
+
+These functions were first was added to OpenSSL 0.9.8
+
+=cut