# 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http://en.wikipedia.org/wiki/Online_Certificate_Status_Protocol) to look up the certificate online and check if it has been revoked (unless -no-ocsp has been specified).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

The pdfsig software and documentation are copyright 1996-2004 Glyph & Cog, LLC and copyright 2005-2015 The Poppler Developers - http://poppler.freedesktop.org

# SEE ALSO

pdfdetach(1), pdffonts(1), pdfimages(1), pdfinfo(1), pdftocairo(1), pdftohtml(1), pdftoppm(1), pdftops(1), pdftotext(1) pdfseparate(1), pdfunite(1) certutil(1)