xmlsec1: xmlsec1 (XML Security Library) xmlsec1: xmlsec1: XML Security Library is a companion C library to LibXML, supporting xmlsec1: the major XML security standards: XML Signature, XML Encryption, xmlsec1: Canonical XML, Exclusive Canonical XML. xmlsec1: xmlsec1: xmlsec1: xmlsec1: xmlsec1: xmlsec1: