Openssl asn1parse命令

openssl asn1parse [-inform PEM|DER] [-in filename] [-out filename] [-noout] [-offset number] [-length number] [-i][ -dump ] [dlimit number] [-oid filename] [-strparse offset] [-genstr string ] [-genconf file]

 -inform arg   input format - one of DER PEM
 -in arg       input file
 -out arg      output file (output format is always DER
 -noout arg    don‘t produce any output
 -offset arg   offset into file
 -length arg   length of section in file
 -i            indent entries
 -dump         dump unknown data in hex form
 -dlimit arg   dump the first arg bytes of unknown data in hex form
 -oid file     file of extra oid definitions
 -strparse offset
               a series of these can be used to ‘dig‘ into multiple
               ASN1 blob wrappings
 -genstr str   string to generate ASN1 structure from
 -genconf file file to generate ASN1 structure from

参考：http://blog.csdn.net/lucien_cc/article/details/18407451
     http://www.netfoucs.com/article/as3luyuan123/45053.html