1=pod 2 3=head1 NAME 4 5CMS_get0_SignerInfos, CMS_SignerInfo_get0_signer_id, CMS_SignerInfo_get0_signature, CMS_SignerInfo_cert_cmp, CMS_set1_signer_cert - CMS signedData signer functions. 6 7=head1 SYNOPSIS 8 9 #include <openssl/cms.h> 10 11 STACK_OF(CMS_SignerInfo) *CMS_get0_SignerInfos(CMS_ContentInfo *cms); 12 13 int CMS_SignerInfo_get0_signer_id(CMS_SignerInfo *si, ASN1_OCTET_STRING **keyid, X509_NAME **issuer, ASN1_INTEGER **sno); 14 ASN1_OCTET_STRING *CMS_SignerInfo_get0_signature(CMS_SignerInfo *si); 15 int CMS_SignerInfo_cert_cmp(CMS_SignerInfo *si, X509 *cert); 16 void CMS_SignerInfo_set1_signer_cert(CMS_SignerInfo *si, X509 *signer); 17 18=head1 DESCRIPTION 19 20The function CMS_get0_SignerInfos() returns all the CMS_SignerInfo structures 21associated with a CMS signedData structure. 22 23CMS_SignerInfo_get0_signer_id() retrieves the certificate signer identifier 24associated with a specific CMS_SignerInfo structure B<si>. Either the 25keyidentifier will be set in B<keyid> or B<both> issuer name and serial number 26in B<issuer> and B<sno>. 27 28CMS_SignerInfo_get0_signature() retrieves the signature associated with 29B<si> in a pointer to an ASN1_OCTET_STRING structure. This pointer returned 30corresponds to the internal signature value if B<si> so it may be read or 31modified. 32 33CMS_SignerInfo_cert_cmp() compares the certificate B<cert> against the signer 34identifier B<si>. It returns zero if the comparison is successful and non zero 35if not. 36 37CMS_SignerInfo_set1_signer_cert() sets the signers certificate of B<si> to 38B<signer>. 39 40=head1 NOTES 41 42The main purpose of these functions is to enable an application to lookup 43signers certificates using any appropriate technique when the simpler method 44of CMS_verify() is not appropriate. 45 46In typical usage and application will retrieve all CMS_SignerInfo structures 47using CMS_get0_SignerInfo() and retrieve the identifier information using 48CMS. It will then obtain the signer certificate by some unspecified means 49(or return and error if it cannot be found) and set it using 50CMS_SignerInfo_set1_signer_cert(). 51 52Once all signer certificates have been set CMS_verify() can be used. 53 54Although CMS_get0_SignerInfos() can return NULL is an error occur B<or> if 55there are no signers this is not a problem in practice because the only 56error which can occur is if the B<cms> structure is not of type signedData 57due to application error. 58 59=head1 RETURN VALUES 60 61CMS_get0_SignerInfos() returns all CMS_SignerInfo structures, or NULL there 62are no signers or an error occurs. 63 64CMS_SignerInfo_get0_signer_id() returns 1 for success and 0 for failure. 65 66CMS_SignerInfo_cert_cmp() returns 0 for a successful comparison and non 67zero otherwise. 68 69CMS_SignerInfo_set1_signer_cert() does not return a value. 70 71Any error can be obtained from L<ERR_get_error(3)|ERR_get_error(3)> 72 73=head1 SEE ALSO 74 75L<ERR_get_error(3)|ERR_get_error(3)>, L<CMS_verify(3)|CMS_verify(3)> 76 77=head1 HISTORY 78 79These functions were first was added to OpenSSL 0.9.8 80 81=cut 82