Manual Pages for UNIX Operating System command usage for man asn1parse

OpenSSL                                       ASN1PARSE(1openssl)



NNNNAAAAMMMMEEEE
     asn1parse - ASN.1 parsing tool

SSSSYYYYNNNNOOOOPPPPSSSSIIIISSSS
     ooooppppeeeennnnssssssssllll aaaassssnnnn1111ppppaaaarrrrsssseeee [---iiinnnnffffoooorrrrmmmm PPPPEEEEMMMM||||DDDDEEEERRRR] [---iiinnnn ffffiiiilllleeeennnnaaaammmmeeee] [---ooouuuutttt
     ffffiiiilllleeeennnnaaaammmmeeee] [---nnnoooooooouuuutttt] [---oooffffffffsssseeeetttt nnnnuuuummmmbbbbeeeerrrr] [---llleeeennnnggggtttthhhh nnnnuuuummmmbbbbeeeerrrr] [---iii]
     [---oooiiiidddd ffffiiiilllleeeennnnaaaammmmeeee] [---sssttttrrrrppppaaaarrrrsssseeee ooooffffffffsssseeeetttt] [---gggeeeennnnssssttttrrrr ssssttttrrrriiiinnnngggg]
     [---gggeeeennnnccccoooonnnnffff ffffiiiilllleeee]

DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
     The aaaassssnnnn1111ppppaaaarrrrsssseeee command is a diagnostic utility that can parse
     ASN.1 structures. It can also be used to extract data from
     ASN.1 formatted data.

OOOOPPPPTTTTIIIIOOOONNNNSSSS
     -iiiinnnnffffoooorrrrmmmm DDDDEEEERRRR||||PPPPEEEEMMMM
         the input format. DDDDEEEERRRR is binary format and PPPPEEEEMMMM (the
         default) is base64 encoded.

     -iiiinnnn ffffiiiilllleeeennnnaaaammmmeeee
         the input file, default is standard input

     -oooouuuutttt ffffiiiilllleeeennnnaaaammmmeeee
         output file to place the DER encoded data into. If this
         option is not present then no data will be output. This
         is most useful when combined with the ---sssttttrrrrppppaaaarrrrsssseeee option.

     -nnnnoooooooouuuutttt
         don't output the parsed version of the input file.

     -ooooffffffffsssseeeetttt nnnnuuuummmmbbbbeeeerrrr
         starting offset to begin parsing, default is start of
         file.

     -lllleeeennnnggggtttthhhh nnnnuuuummmmbbbbeeeerrrr
         number of bytes to parse, default is until end of file.

     -iiii  indents the output according to the "depth" of the
         structures.

     -ooooiiiidddd ffffiiiilllleeeennnnaaaammmmeeee
         a file containing additional OBJECT IDENTIFIERs (OIDs).
         The format of this file is described in the NOTES
         section below.

     -ssssttttrrrrppppaaaarrrrsssseeee ooooffffffffsssseeeetttt
         parse the contents octets of the ASN.1 object starting
         at ooooffffffffsssseeeetttt. This option can be used multiple times to
         "drill down" into a nested structure.

     -ggggeeeennnnssssttttrrrr ssssttttrrrriiiinnnngggg, -ggggeeeennnnccccoooonnnnffff ffffiiiilllleeee
         generate encoded data based on ssssttttrrrriiiinnnngggg, ffffiiiilllleeee or both



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OpenSSL                                       ASN1PARSE(1openssl)



         using ASN1_generate_nconf() format. If ffffiiiilllleeee only is
         present then the string is obtained from the default
         section using the name aaaassssnnnn1111. The encoded data is passed
         through the ASN1 parser and printed out as though it
         came from a file, the contents can thus be examined and
         written to a file using the oooouuuutttt option.

     OOOOUUUUTTTTPPPPUUUUTTTT

     The output will typically contain lines like this:

       0:d=0  hl=4 l= 681 cons: SEQUENCE

     .....

       229:d=3  hl=3 l= 141 prim: BIT STRING
       373:d=2  hl=3 l= 162 cons: cont [ 3 ]
       376:d=3  hl=3 l= 159 cons: SEQUENCE
       379:d=4  hl=2 l=  29 cons: SEQUENCE
       381:d=5  hl=2 l=   3 prim: OBJECT            :X509v3 Subject Key Identifier
       386:d=5  hl=2 l=  22 prim: OCTET STRING
       410:d=4  hl=2 l= 112 cons: SEQUENCE
       412:d=5  hl=2 l=   3 prim: OBJECT            :X509v3 Authority Key Identifier
       417:d=5  hl=2 l= 105 prim: OCTET STRING
       524:d=4  hl=2 l=  12 cons: SEQUENCE

     .....

     This example is part of a self signed certificate. Each line
     starts with the offset in decimal. dddd====XXXXXXXX specifies the
     current depth. The depth is increased within the scope of
     any SET or SEQUENCE. hhhhllll====XXXXXXXX gives the header length (tag and
     length octets) of the current type. llll====XXXXXXXX gives the length of
     the contents octets.

     The ---iii option can be used to make the output more readable.

     Some knowledge of the ASN.1 structure is needed to interpret
     the output.

     In this example the BIT STRING at offset 229 is the
     certificate public key.  The contents octets of this will
     contain the public key information. This can be examined
     using the option ---sssttttrrrrppppaaaarrrrsssseeee 222222229999 to yield:

         0:d=0  hl=3 l= 137 cons: SEQUENCE
         3:d=1  hl=3 l= 129 prim: INTEGER           :E5D21E1F5C8D208EA7A2166C7FAF9F6BDF2059669C60876DDB70840F1A5AAFA59699FE471F379F1DD6A487E7D5409AB6A88D4A9746E24B91D8CF55DB3521015460C8EDE44EE8A4189F7A7BE77D6CD3A9AF2696F486855CF58BF0EDF2B4068058C7A947F52548DDF7E15E96B385F86422BEA9064A3EE9E1158A56E4A6F47E5897
       135:d=1  hl=2 l=   3 prim: INTEGER           :010001


NNNNOOOOTTTTEEEESSSS
     If an OID is not part of OpenSSL's internal table it will be



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OpenSSL                                       ASN1PARSE(1openssl)



     represented in numerical form (for example 1.2.3.4). The
     file passed to the ---oooiiiidddd option allows additional OIDs to be
     included. Each line consists of three columns, the first
     column is the OID in numerical format and should be followed
     by white space. The second column is the "short name" which
     is a single word followed by white space. The final column
     is the rest of the line and is the "long name". aaaassssnnnn1111ppppaaaarrrrsssseeee
     displays the long name. Example:

     1.2.3.4   shortName A long name

EEEEXXXXAAAAMMMMPPPPLLLLEEEESSSS
     Parse a file:

      openssl asn1parse -in file.pem

     Parse a DER file:

      openssl asn1parse -inform DER -in file.der

     Generate a simple UTF8String:

      openssl asn1parse -genstr 'UTF8:Hello World'

     Generate and write out a UTF8String, don't print parsed
     output:

      openssl asn1parse -genstr 'UTF8:Hello World' -noout -out utf8.der

     Generate using a config file:

      openssl asn1parse -genconf asn1.cnf -noout -out asn1.der

     Example config file:

      asn1=SEQUENCE:seq_sect

      [seq_sect]

      field1=BOOL:TRUE
      field2=EXP:0, UTF8:some random string


BBBBUUUUGGGGSSSS
     There should be options to change the format of output
     lines. The output of some ASN.1 types is not well handled
     (if at all).








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OpenSSL                                       ASN1PARSE(1openssl)























































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