Ubuntu Manpage: pdfsig - Portable Document Format (PDF) digital signatures tool

Provided by: poppler-utils_25.03.0-3ubuntu1_amd64

NAME

       pdfsig - Portable Document Format (PDF) digital signatures tool

SYNOPSIS

       pdfsig [options] [PDF-file] [Output-file]

DESCRIPTION

       pdfsig  verifies  the digital signatures in a PDF document.  It also displays the identity of each signer
       (commonName field and full distinguished name of the signer  certificate),  the  time  and  date  of  the
       signature,  the  hash  algorithm used for signing, the type of the signature as stated in the PDF and the
       signed ranges with a statement wether the total document is signed.   It  can  also  sign  PDF  documents
       (options -add-signature or -sign).

       pdfsig  uses the trusted certificates stored either in the Network Security Services (NSS) Database or in
       GnuPG's S/MIME system (gpgsm).

       pdfsig    also    uses    the    Online    Certificate    Status    Protocol     (OCSP)     (refer     to
       http://en.wikipedia.org/wiki/Online_Certificate_Status_Protocol)  to  look  up the certificate online and
       check if it has been revoked (unless -no-ocsp has been specified).

       If the NSS backend is used, the NSS Database is searched for in the following locations:

       •      If the -nssdir option is specified, the directory specified by this option.

       •      The    NSS    Certificate    database     in     the     default     Firefox     profile.     i.e.
              $HOME/.mozilla/firefox/*.default.

       •      The NSS Certificate database in /etc/pki/nssdb.

       If the GPG backend is used, the S/MIME certificate is read from $GNUPGHOME, defaulting to $HOME/.gnupg

OPTIONS

-nssdir [prefix]directory
Specify the database directory containing the certificate and key database files. See certutil(1)
-d option for details of the prefix. If not specified the other search locations described in
DESCRIPTION are used.

-nss-pwd password
Specify the password needed to access the NSS database (if any).

-nocert
Do not validate the certificate.

-no-ocsp
Do not perform online OCSP certificate revocation check (local Certificate Revocation Lists (CRL)
are still used).

-no-appearance
Do not add appearance information when signing existing fields (signer name and date).

-aia Enable the use of Authority Information Access (AIA) extension to fetch missing certificates to
build the certificate chain.

-dump Dump all signatures into current directory in their native format. Most likely it is either a
unpadded or zero-padded CMS/PKCS7 bundle.

-add-signature
Add a new signature to the document.

-new-signature-field-name name
Specifies the field name to be used when adding a new signature. A random ID will be used by
default.

-sign field
Sign the document in the specified signature field present in the document (must be unsigned).
Field can be specified by field name (string) or the n-th signature field in the document
(integer).

-nick nickname
Use the certificate with the given nickname for signing (NSS backend). If nickname starts with
pkcs11:, it's treated as PKCS#11 URI (NSS backend). If the nickname is given as a fingerprint, it
will be the certificate used (GPG backend)

-backend backend
Use the specified backeng for cryptographic signatures

-kpw password
Use the given password for the signing key (this might be missing if the key isn't password
protected).

-digest algorithm
Use the given digest algorithm for signing (default: SHA256).

-reason reason
Set the given reason string for the signature (default: no reason set).

-etsi Create a signature of type ETSI.CAdES.detached instead of adbe.pkcs7.detached.

-list-nicks
List available nicknames in the NSS database.

-list-backends
List available backends for cryptographic signatures

-v Print copyright and version information.

-h Print usage information. (-help and --help are equivalent.)

EXAMPLES

       pdfsig signed_file.pdf
              Displays signature info for signed_file.pdf.

       pdfsig input.pdf output.pdf -add-signature -nss-pwd password -nick my-cert -reason 'for fun!'
              Creates a new pdf named output.pdf  with  the  contents  of  input.pdf  signed  by  the  'my-cert'
              certificate.

       pdfsig input.pdf output.pdf -add-signature -nss-pwd password -nick
       'pkcs11:token=smartcard0;object=Second%20certificate;type=cert'
              Same,  but uses a PKCS#11 URI as defined in IETF RFC 7512 to select the certificate to be used for
              signing.

       pdfsig input.pdf output.pdf -sign 0 -nss-pwd password -nick my-cert -reason 'for fun!'
              Creates a new pdf named output.pdf  with  the  contents  of  input.pdf  signed  by  the  'my-cert'
              certificate. input.pdf must have an already existing un-signed signature field.

AUTHOR