pkcs7 - PKCS#7 utility


   openssl pkcs7 [-inform PEM|DER] [-outform PEM|DER] [-in filename] [-out
   filename] [-print_certs] [-text] [-noout] [-engine id]


   The pkcs7 command processes PKCS#7 files in DER or PEM format.


   -inform DER|PEM
       This specifies the input format. DER format is DER encoded PKCS#7
       v1.5 structure.PEM (the default) is a base64 encoded version of the
       DER form with header and footer lines.

   -outform DER|PEM
       This specifies the output format, the options have the same meaning
       as the -inform option.

   -in filename
       This specifies the input filename to read from or standard input if
       this option is not specified.

   -out filename
       specifies the output filename to write to or standard output by

       prints out any certificates or CRLs contained in the file. They are
       preceded by their subject and issuer names in one line format.

       prints out certificates details in full rather than just subject
       and issuer names.

       don't output the encoded version of the PKCS#7 structure (or
       certificates is -print_certs is set).

   -engine id
       specifying an engine (by its unique id string) will cause pkcs7 to
       attempt to obtain a functional reference to the specified engine,
       thus initialising it if needed. The engine will then be set as the
       default for all available algorithms.


   Convert a PKCS#7 file from PEM to DER:

    openssl pkcs7 -in file.pem -outform DER -out file.der

   Output all certificates in a file:

    openssl pkcs7 -in file.pem -print_certs -out certs.pem


   The PEM PKCS#7 format uses the header and footer lines:

    -----BEGIN PKCS7-----

    -----END PKCS7-----
   For compatibility with some CAs it will also accept:


    -----END CERTIFICATE-----


   There is no option to print out all the fields of a PKCS#7 file.

   This PKCS#7 routines only understand PKCS#7 v 1.5 as specified in
   RFC2315 they cannot currently parse, for example, the new CMS as
   described in RFC2630.




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