NSS tools : signtool¶

Name

signtool — Digitally sign objects and files.

Synopsis

signtool [-k keyName] -h -H -l -L -M
-v -w
-G nickname -s size -b basename [[-c
Compression
Level] ] [[-d cert-dir] ] [[-i installer script] ] [[-m metafile] ] [[-x
name] ] [[-f filename] ] [[-t|–token tokenname] ] [[-e extension] ] [[-o]
] [[-z] ] [[-X] ] [[–outfile] ] [[–verbose value] ] [[–norecurse] ]
[[–leavearc] ] [[-j directory] ] [[-Z jarfile] ] [[-O] ] [[-p password] ]
[directory-tree] [archive]

Description

The Signing Tool, signtool, creates digital signatures and uses a Java
Archive (JAR) file to associate the signatures with files in a directory.
Electronic software distribution over any network involves potential
security problems. To help address some of these problems, you can
associate digital signatures with the files in a JAR archive. Digital
signatures allow SSL-enabled clients to perform two important operations:
* Confirm the identity of the individual, company, or other entity whose
digital signature is associated with the files
* Check whether the files have been tampered with since being signed
If you have a signing certificate, you can use Netscape Signing Tool to
digitally sign files and package them as a JAR file. An object-signing
certificate is a special kind of certificate that allows you to associate
your digital signature with one or more files.
An individual file can potentially be signed with multiple digital
signatures. For example, a commercial software developer might sign the
files that constitute a software product to prove that the files are
indeed from a particular company. A network administrator manager might
sign the same files with an additional digital signature based on a
company-generated certificate to indicate that the product is approved for
use within the company.
The significance of a digital signature is comparable to the significance
of a handwritten signature. Once you have signed a file, it is difficult
to claim later that you didn’t sign it. In some situations, a digital
signature may be considered as legally binding as a handwritten signature.
Therefore, you should take great care to ensure that you can stand behind
any file you sign and distribute.
For example, if you are a software developer, you should test your code to
make sure it is virus-free before signing it. Similarly, if you are a
network administrator, you should make sure, before signing any code, that
it comes from a reliable source and will run correctly with the software
installed on the machines to which you are distributing it.
Before you can use Netscape Signing Tool to sign files, you must have an
object-signing certificate, which is a special certificate whose
associated private key is used to create digital signatures. For testing
purposes only, you can create an object-signing certificate with Netscape
Signing Tool 1.3. When testing is finished and you are ready to
disitribute your software, you should obtain an object-signing certificate
from one of two kinds of sources:
* An independent certificate authority (CA) that authenticates your
identity and charges you a fee. You typically get a certificate from an
independent CA if you want to sign software that will be distributed over
the Internet.
* CA server software running on your corporate intranet or extranet.
Netscape Certificate Management System provides a complete management
solution for creating, deploying, and managing certificates, including CAs
that issue object-signing certificates.
You must also have a certificate for the CA that issues your signing
certificate before you can sign files. If the certificate authority’s
certificate isn’t already installed in your copy of Communicator, you
typically install it by clicking the appropriate link on the certificate
authority’s web site, for example on the page from which you initiated
enrollment for your signing certificate. This is the case for some test
certificates, as well as certificates issued by Netscape Certificate
Management System: you must download the CA certificate in addition to
obtaining your own signing certificate. CA certificates for several
certificate authorities are preinstalled in the Communicator certificate
database.
When you receive an object-signing certificate for your own use, it is
automatically installed in your copy of the Communicator client software.
Communicator supports the public-key cryptography standard known as PKCS
#12, which governs key portability. You can, for example, move an
object-signing certificate and its associated private key from one
computer to another on a credit-card-sized device called a smart card.

Options

-b basename

Specifies the base filename for the .rsa and .sf files in the
META-INF directory to conform with the JAR format. For example, -b
signatures causes the files to be named signatures.rsa and
signatures.sf. The default is signtool.

-c#

Specifies the compression level for the -J or -Z option. The
symbol # represents a number from 0 to 9, where 0 means no
compression and 9 means maximum compression. The higher the level
of compression, the smaller the output but the longer the
operation takes. If the -c# option is not used with either the -J
or the -Z option, the default compression value used by both the
-J and -Z options is 6.

-d certdir

Specifies your certificate database directory; that is, the
directory in which you placed your key3.db and cert7.db files. To
specify the current directory, use “-d.” (including the period).
The Unix version of signtool assumes ~/.netscape unless told
otherwise. The NT version of signtool always requires the use of
the -d option to specify where the database files are located.

-e extension

Tells signtool to sign only files with the given extension; for
example, use -e”.class” to sign only Java class files. Note that
with Netscape Signing Tool version 1.1 and later this option can
appear multiple times on one command line, making it possible to
specify multiple file types or classes to include.

-f commandfile

Specifies a text file containing Netscape Signing Tool options and
arguments in keyword=value format. All options and arguments can
be expressed through this file. For more information about the
syntax used with this file, see “Tips and Techniques”.

-i scriptname

Specifies the name of an installer script for SmartUpdate. This
script installs files from the JAR archive in the local system
after SmartUpdate has validated the digital signature. For more
details, see the description of -m that follows. The -i option
provides a straightforward way to provide this information if you
don’t need to specify any metadata other than an installer script.

-j directory

Specifies a special JavaScript directory. This option causes the
specified directory to be signed and tags its entries as inline
JavaScript. This special type of entry does not have to appear in
the JAR file itself. Instead, it is located in the HTML page
containing the inline scripts. When you use signtool -v, these
entries are displayed with the string NOT PRESENT.

-k key … directory

Specifies the nickname (key) of the certificate you want to sign
with and signs the files in the specified directory. The directory
to sign is always specified as the last command-line argument.
Thus, it is possible to write signtool -k MyCert -d . signdir You
may have trouble if the nickname contains a single quotation mark.
To avoid problems, escape the quotation mark using the escape
conventions for your platform. It’s also possible to use the -k
option without signing any files or specifying a directory. For
example, you can use it with the -l option to get detailed
information about a particular signing certificate.

-G nickname

Generates a new private-public key pair and corresponding
object-signing certificate with the given nickname. The newly
generated keys and certificate are installed into the key and
certificate databases in the directory specified by the -d option.
With the NT version of Netscape Signing Tool, you must use the -d
option with the -G option. With the Unix version of Netscape
Signing Tool, omitting the -d option causes the tool to install
the keys and certificate in the Communicator key and certificate
databases. If you are installing the keys and certificate in the
Communicator databases, you must exit Communicator before using
this option; otherwise, you risk corrupting the databases. In all
cases, the certificate is also output to a file named x509.cacert,
which has the MIME-type application/x-x509-ca-cert. Unlike
certificates normally used to sign finished code to be distributed
over a network, a test certificate created with -G is not signed
by a recognized certificate authority. Instead, it is self-signed.
In addition, a single test signing certificate functions as both
an object-signing certificate and a CA. When you are using it to
sign objects, it behaves like an object-signing certificate. When
it is imported into browser software such as Communicator, it
behaves like an object-signing CA and cannot be used to sign
objects. The -G option is available in Netscape Signing Tool 1.0
and later versions only. By default, it produces only RSA
certificates with 1024-byte keys in the internal token. However,
you can use the -s option specify the required key size and the -t
option to specify the token. For more information about the use of
the -G option, see “Generating Test Object-Signing
Certificates””Generating Test Object-Signing Certificates” on page
1241.

-l

Lists signing certificates, including issuing CAs. If any of your
certificates are expired or invalid, the list will so specify.
This option can be used with the -k option to list detailed
information about a particular signing certificate. The -l option
is available in Netscape Signing Tool 1.0 and later versions only.

-J

Signs a directory of HTML files containing JavaScript and creates
as many archive files as are specified in the HTML tags. Even if
signtool creates more than one archive file, you need to supply
the key database password only once. The -J option is available
only in Netscape Signing Tool 1.0 and later versions. The -J
option cannot be used at the same time as the -Z option. If the
-c# option is not used with the -J option, the default compression
value is 6. Note that versions 1.1 and later of Netscape Signing
Tool correctly recognizes the CODEBASE attribute, allows paths to
be expressed for the CLASS and SRC attributes instead of filenames
only, processes LINK tags and parses HTML correctly, and offers
clearer error messages.

-L

Lists the certificates in your database. An asterisk appears to
the left of the nickname for any certificate that can be used to
sign objects with signtool.

–leavearc

Retains the temporary .arc (archive) directories that the -J
option creates. These directories are automatically erased by
default. Retaining the temporary directories can be an aid to
debugging.

-m metafile

Specifies the name of a metadata control file. Metadata is signed
information attached either to the JAR archive itself or to files
within the archive. This metadata can be any ASCII string, but is
used mainly for specifying an installer script. The metadata file
contains one entry per line, each with three fields: field #1:
file specification, or + if you want to specify global metadata
(that is, metadata about the JAR archive itself or all entries in
the archive) field #2: the name of the data you are specifying;
for example: Install-Script field #3: data corresponding to the
name in field #2 For example, the -i option uses the equivalent of
this line: + Install-Script: script.js This example associates a
MIME type with a file: movie.qt MIME-Type: video/quicktime For
information about the way installer script information appears in
the manifest file for a JAR archive, see The JAR Format on
Netscape DevEdge.

-M

Lists the PKCS #11 modules available to signtool, including smart
cards. The -M option is available in Netscape Signing Tool 1.0 and
later versions only. For information on using Netscape Signing
Tool with smart cards, see “Using Netscape Signing Tool with Smart
Cards”. For information on using the -M option to verify
FIPS-140-1 validated mode, see “Netscape Signing Tool and
FIPS-140-1”.

–norecurse

Blocks recursion into subdirectories when signing a directory’s

contents or when parsing HTML.

-o

Optimizes the archive for size. Use this only if you are signing
very large archives containing hundreds of files. This option
makes the manifest files (required by the JAR format) considerably
smaller, but they contain slightly less information.

–outfile outputfile

Specifies a file to receive redirected output from Netscape

Signing Tool.

-p password

Specifies a password for the private-key database. Note that the

password entered on the command line is displayed as plain text.

-s keysize

Specifies the size of the key for generated certificate. Use the
-M option to find out what tokens are available. The -s option can
be used with the -G option only.

-t token

Specifies which available token should generate the key and
receive the certificate. Use the -M option to find out what tokens
are available. The -t option can be used with the -G option only.

-v archive

Displays the contents of an archive and verifies the cryptographic
integrity of the digital signatures it contains and the files with
which they are associated. This includes checking that the
certificate for the issuer of the object-signing certificate is
listed in the certificate database, that the CA’s digital
signature on the object-signing certificate is valid, that the
relevant certificates have not expired, and so on.

–verbosity value

Sets the quantity of information Netscape Signing Tool generates
in operation. A value of 0 (zero) is the default and gives full
information. A value of -1 suppresses most messages, but not error
messages.

-w archive

Displays the names of signers of any files in the archive.

-x directory

Excludes the specified directory from signing. Note that with
Netscape Signing Tool version 1.1 and later this option can appear
multiple times on one command line, making it possible to specify
several particular directories to exclude.

-z

Tells signtool not to store the signing time in the digital
signature. This option is useful if you want the expiration date
of the signature checked against the current date and time rather
than the time the files were signed.

-Z jarfile

Creates a JAR file with the specified name. You must specify this
option if you want signtool to create the JAR file; it does not do
so automatically. If you don’t specify -Z, you must use an
external ZIP tool to create the JAR file. The -Z option cannot be
used at the same time as the -J option. If the -c# option is not
used with the -Z option, the default compression value is 6.

The Command File Format

Entries in a Netscape Signing Tool command file have this general format:

keyword=value Everything before the = sign on a single line is a keyword,

and everything from the = sign to the end of line is a value. The value

may include = signs; only the first = sign on a line is interpreted. Blank

lines are ignored, but white space on a line with keywords and values is

assumed to be part of the keyword (if it comes before the equal sign) or

part of the value (if it comes after the first equal sign). Keywords are

case insensitive, values are generally case sensitive. Since the = sign

and newline delimit the value, it should not be quoted.

Subsection

basename

Same as -b option.

compression

Same as -c option.

certdir

Same as -d option.

extension

Same as -e option.

generate

Same as -G option.

installscript

Same as -i option.

javascriptdir

Same as -j option.

htmldir

Same as -J option.

certname

Nickname of certificate, as with -k and -l -k options.

signdir

The directory to be signed, as with -k option.

list

Same as -l option. Value is ignored, but = sign must be present.

listall

Same as -L option. Value is ignored, but = sign must be present.

metafile

Same as -m option.

modules

Same as -M option. Value is ignored, but = sign must be present.

optimize

Same as -o option. Value is ignored, but = sign must be present.

password

Same as -p option.

keysize

Same as -s option.

token

Same as -t option.

verify

Same as -v option.

who

Same as -w option.

exclude

Same as -x option.

notime

Same as -z option. value is ignored, but = sign must be present.

jarfile

Same as -Z option.

outfile

Name of a file to which output and error messages will be

redirected. This option has no command-line equivalent.

Extended Examples

The following example will do this and that
Listing Available Signing Certificates
You use the -L option to list the nicknames for all available certificates
and check which ones are signing certificates.

signtool -L

using certificate directory: /u/jsmith/.netscape

S Certificates

- ————

BBN Certificate Services CA Root 1
IBM World Registry CA
VeriSign Class 1 CA - Individual Subscriber - VeriSign, Inc.
GTE CyberTrust Root CA
Uptime Group Plc. Class 4 CA

* Verisign Object Signing Cert

Integrion CA
GTE CyberTrust Secure Server CA
AT&T Directory Services

* test object signing cert

Uptime Group Plc. Class 1 CA

VeriSign Class 1 Primary CA

- ————

Certificates that can be used to sign objects have *’s to their left.

Two signing certificates are displayed: Verisign Object Signing Cert and
test object signing cert.
You use the -l option to get a list of signing certificates only,
including the signing CA for each.

signtool -l

using certificate directory: /u/jsmith/.netscape

Object signing certificates

—————————————

Verisign Object Signing Cert

Issued by: VeriSign, Inc. - Verisign, Inc.

Expires: Tue May 19, 1998

test object signing cert

Issued by: test object signing cert (Signtool 1.0 Testing

Certificate (960187691))

Expires: Sun May 17, 1998

—————————————

For a list including CAs, use the -L option.
Signing a File
1. Create an empty directory.

mkdir signdir

2. Put some file into it.

echo boo > signdir/test.f

3. Specify the name of your object-signing certificate and sign the

directory.

signtool -k MySignCert -Z testjar.jar signdir

using key “MySignCert”

using certificate directory: /u/jsmith/.netscape

Generating signdir/META-INF/manifest.mf file..

–> test.f

adding signdir/test.f to testjar.jar

Generating signtool.sf file..

Enter Password or Pin for “Communicator Certificate DB”:

adding signdir/META-INF/manifest.mf to testjar.jar

adding signdir/META-INF/signtool.sf to testjar.jar

adding signdir/META-INF/signtool.rsa to testjar.jar

tree “signdir” signed successfully

4. Test the archive you just created.

signtool -v testjar.jar

using certificate directory: /u/jsmith/.netscape

archive “testjar.jar” has passed crypto verification.

status   path
————   ——————-
verified   test.f
Using Netscape Signing Tool with a ZIP Utility
To use Netscape Signing Tool with a ZIP utility, you must have the utility
in your path environment variable. You should use the zip.exe utility
rather than pkzip.exe, which cannot handle long filenames. You can use a
ZIP utility instead of the -Z option to package a signed archive into a
JAR file after you have signed it:

cd signdir

zip -r ../myjar.jar *
adding: META-INF/ (stored 0%)
adding: META-INF/manifest.mf (deflated 15%)
adding: META-INF/signtool.sf (deflated 28%)
adding: META-INF/signtool.rsa (stored 0%)
adding: text.txt (stored 0%)
Generating the Keys and Certificate
The signtool option -G generates a new public-private key pair and
certificate. It takes the nickname of the new certificate as an argument.
The newly generated keys and certificate are installed into the key and
certificate databases in the directory specified by the -d option. With
the NT version of Netscape Signing Tool, you must use the -d option with
the -G option. With the Unix version of Netscape Signing Tool, omitting
the -d option causes the tool to install the keys and certificate in the
Communicator key and certificate databases. In all cases, the certificate
is also output to a file named x509.cacert, which has the MIME-type
application/x-x509-ca-cert.
Certificates contain standard information about the entity they identify,
such as the common name and organization name. Netscape Signing Tool
prompts you for this information when you run the command with the -G
option. However, all of the requested fields are optional for test
certificates. If you do not enter a common name, the tool provides a
default name. In the following example, the user input is in boldface:

signtool -G MyTestCert

using certificate directory: /u/someuser/.netscape

Enter certificate information. All fields are optional. Acceptable

characters are numbers, letters, spaces, and apostrophes.

certificate common name: Test Object Signing Certificate

organization: Netscape Communications Corp.

organization unit: Server Products Division

state or province: California

country (must be exactly 2 characters): US

username: someuser

email address: someuser@netscape.com

Enter Password or Pin for “Communicator Certificate DB”: [Password will not echo]

generated public/private key pair

certificate request generated

certificate has been signed

certificate “MyTestCert” added to database

Exported certificate to x509.raw and x509.cacert.

The certificate information is read from standard input. Therefore, the
information can be read from a file using the redirection operator (<) in
some operating systems. To create a file for this purpose, enter each of
the seven input fields, in order, on a separate line. Make sure there is a
newline character at the end of the last line. Then run signtool with
standard input redirected from your file as follows:

signtool -G MyTestCert inputfile

The prompts show up on the screen, but the responses will be automatically
read from the file. The password will still be read from the console
unless you use the -p option to give the password on the command line.
Using the -M Option to List Smart Cards
You can use the -M option to list the PKCS #11 modules, including smart
cards, that are available to signtool:

signtool -d “c:netscapeusersjsmith” -M

using certificate directory: c:netscapeusersusername

Listing of PKCS11 modules

———————————————–

1. Netscape Internal PKCS #11 Module

(this module is internally loaded)
slots: 2 slots attached
status: loaded

slot: Communicator Internal Cryptographic Services Version 4.0

token: Communicator Generic Crypto Svcs

slot: Communicator User Private Key and Certificate Services

token: Communicator Certificate DB

2. CryptOS

(this is an external module)

DLL name: core32

slots: 1 slots attached
status: loaded
slot: Litronic 210
token:
———————————————–
Using Netscape Signing Tool and a Smart Card to Sign Files
The signtool command normally takes an argument of the -k option to
specify a signing certificate. To sign with a smart card, you supply only
the fully qualified name of the certificate.
To see fully qualified certificate names when you run Communicator, click
the Security button in Navigator, then click Yours under Certificates in
the left frame. Fully qualified names are of the format smart
card:certificate, for example “MyCard:My Signing Cert”. You use this name
with the -k argument as follows:

signtool -k “MyCard:My Signing Cert” directory

Verifying FIPS Mode

Use the -M option to verify that you are using the FIPS-140-1 module.

signtool -d “c:netscapeusersjsmith” -M

using certificate directory: c:netscapeusersjsmith

Listing of PKCS11 modules

———————————————–

1. Netscape Internal PKCS #11 Module

(this module is internally loaded)
slots: 2 slots attached
status: loaded

slot: Communicator Internal Cryptographic Services Version 4.0

token: Communicator Generic Crypto Svcs

slot: Communicator User Private Key and Certificate Services

token: Communicator Certificate DB

———————————————–

This Unix example shows that Netscape Signing Tool is using a FIPS-140-1

module:

signtool -d “c:netscapeusersjsmith” -M

using certificate directory: c:netscapeusersjsmith

Enter Password or Pin for “Communicator Certificate DB”: [password will not echo]

Listing of PKCS11 modules

———————————————–

1. Netscape Internal FIPS PKCS #11 Module

(this module is internally loaded)

slots: 1 slots attached

status: loaded

slot: Netscape Internal FIPS-140-1 Cryptographic Services

token: Communicator Certificate DB

———————————————–