signver - Man Page

Verify a detached PKCS#7 signature for a file​.

Synopsis

signtool -A | -V  -d directory [-a] [-i input_file] [-o output_file] [-s signature_file] [-v]

Status

This documentation is still work in progress​. Please contribute to the initial review in Mozilla NSS bug 836477[1]

Description

The Signature Verification Tool, signver, is a simple command-line utility that unpacks a base-64-encoded PKCS#7 signed object and verifies the digital signature using standard cryptographic techniques​. The Signature Verification Tool can also display the contents of the signed object​.

Options

-A

Displays all of the information in the PKCS#7 signature​.

-V

Verifies the digital signature​.

-d directory

Specify the database directory which contains the certificates and keys​.

signver supports SQLite databases (cert9​.db, key4​.db, and pkcs11​.txt)​.

-a

Sets that the given signature file is in ASCII format​.

-i input_file

Gives the input file for the object with signed data​.

-o output_file

Gives the output file to which to write the results​.

-s signature_file

Gives the input file for the digital signature​.

-v

Enables verbose output​.

Extended Examples

Verifying a Signature

The -V option verifies that the signature in a given signature file is valid when used to sign the given object (from the input file)​.

signver -V -s signature_file -i signed_file -d /home/my/sharednssdb

signatureValid=yes

Printing Signature Data

The -A option prints all of the information contained in a signature file​. Using the -o option prints the signature file information to the given output file rather than stdout​.

signver -A -s signature_file -o output_file

NSS Database Types

NSS originally used BerkeleyDB databases to store security information​. The last versions of these legacy databases are:

BerkeleyDB has performance limitations, though, which prevent it from being easily used by multiple applications simultaneously​. NSS has some flexibility that allows applications to use their own, independent database engine while keeping a shared database and working around the access issues​. Still, NSS requires more flexibility to provide a truly shared security database​.

In 2009, NSS introduced a new set of databases that are SQLite databases rather than BerkleyDB​. These new databases provide more accessibility and performance:

Because the SQLite databases are designed to be shared, these are the shared database type​. The shared database type is preferred; the legacy format is included for backward compatibility​.

By default, the tools (certutil, pk12util, modutil) assume that the given security databases use the SQLite type​.

For an engineering draft on the changes in the shared NSS databases, see the NSS project wiki:

See Also

signtool (1)

The NSS wiki has information on the new database design and how to configure applications to use it​.

Additional Resources

For information about NSS and other tools related to NSS (like JSS), check out the NSS project wiki at http://www​.mozilla​.org/projects/security/pki/nss/​. The NSS site relates directly to NSS code changes and releases​.

Mailing lists: https://lists​.mozilla​.org/listinfo/dev-tech-crypto

IRC: Freenode at #dogtag-pki

Authors

The NSS tools were written and maintained by developers with Netscape, Red Hat, Sun, Oracle, Mozilla, and Google​.

Authors: Elio Maldonado <emaldona@redhat​.com>, Deon Lackey <dlackey@redhat​.com>​.

License

Licensed under the Mozilla Public License, v​. 2​.0​. If a copy of the MPL was not distributed with this file, You can obtain one at http://mozilla​.org/MPL/2​.0/​.

Notes

1.

Mozilla NSS bug 836477
https://bugzilla.mozilla.org/show_bug.cgi?id=836477

Referenced By

signtool(1).

27 August 2026 nss-tools NSS Security Tools