jarsigner(1)jarsigner(1)NAMEjarsigner - JAR signing and verification tool
SYNOPSISjarsigner [ options ] jar-file alias
jarsigner-verify [ options ] jar-file alias
DESCRIPTION
The jarsigner tool is used for two purposes:
1. to sign Java ARchive (JAR) files, and
2. to verify the signatures and integrity of signed JAR files.
The JAR feature enables the packaging of class files, images, sounds,
and other digital data in a single file for faster and easier distribu‐
tion. A tool named jar enables developers to produce JAR files.
A digital signature is a string of bits that is computed from some data
(the data being "signed") and the private key of an entity (a person,
company, etc.). Like a handwritten signature, a digital signature has
many useful characteristics:
· Its authenticity can be verified, via a computation that uses the
public key corresponding to the private key used to generate the sig‐
nature.
· It cannot be forged, assuming the private key is kept secret.
· It is a function of the data signed and thus can't be claimed to be
the signature for other data as well.
· The signed data cannot be changed; if it is, the signature will no
longer verify as being authentic.
In order for an entity's signature to be generated for a file, the
entity must first have a public/private key pair associated with it,
and also one or more certificates authenticating its public key. A cer‐
tificate is a digitally signed statement from one entity, saying that
the public key of some other entity has a particular value.
jarsigner uses key and certificate information from a keystore to gen‐
erate digital signatures for JAR files. A keystore is a database of
private keys and their associated X.509 certificate chains authenticat‐
ing the corresponding public keys. The keytool utility is used to cre‐
ate and administer keystores.
jarsigner uses an entity's private key to generate a signature. The
signed JAR file contains, among other things, a copy of the certificate
from the keystore for the public key corresponding to the private key
used to sign the file. jarsigner can verify the digital signature of
the signed JAR file using the certificate inside it (in its signature
block file).
At this time, jarsigner can only sign JAR files created by the JDK jar
tool or zip files. (JAR files are the same as zip files, except they
also have a META-INF/MANIFEST.MF file. Such a file will automatically
be created when jarsigner signs a zip file.)
The default jarsigner behavior is to sign a JAR file. Use the -verify
option to instead have it verify a signed JAR file.
Compatibility with JDK 1.1
The keytool and jarsigner tools completely replace the javakey tool
provided in JDK 1.1. These new tools provide more features than
javakey, including the ability to protect the keystore and private keys
with passwords, and the ability to verify signatures in addition to
generating them.
The new keystore architecture replaces the identity database that
javakey created and managed. There is no backwards compatibility
between the keystore format and the database format used by javakey in
1.1. However:
· It is possible to import the information from an identity database
into a keystore, via the keytool -identitydb command
· jarsigner can sign JAR files also previously signed using javakey
· jarsigner can verify JAR files signed using javakey Thus, it recog‐
nizes and can work with signer aliases that are from a JDK 1.1 iden‐
tity database rather than a JDK 1.2 keystore.
The following table explains how JAR files that were signed in JDK
1.1.x are treated in the Java 2 Platform.
Trusted
Identity
imported Policy File
JAR File Identity in into 1.2 grants Privileges
Type 1.1 database keystore privileges to Granted
from 1.1 Identity/Alias
database
(4)
Signed Default
JAR NO NO NO privaleges
granted to
all code.
Unsigned Default
JAR NO NO NO privileges
granted to
all code.
Signed Default
JAR NO YES NO privileges
granted to
all code.
Signed Default
JAR YES/Untrusted NO NO privileges
granted to
all code. (3)
Signed Default
JAR YES/Untrusted NO YES privileges
granted to
all code.
(1,3)
Signed Default
JAR NO YES YES privileges
granted to
all code plus
privileges
granted in
policy file.
Signed Default
JAR YES/Trusted YES YES privileges
granted to
all code plus
privileges
granted in
policy file.
(2)
Signed All
JAR YES/Trusted NO NO privileges
Signed All
JAR YES/Trusted YES NO privileges
(1)
Signed All
JAR YES/Trusted NO YES privileges
(1)
Notes:
1. If an identity/alias is mentioned in the policy file, it must be
imported into the keystore for the policy file to have any effect
on privileges granted.
1. If an identity/alias is mentioned in the policy file, it must be
imported into the keystore for the policy file to have any effect
on privileges granted.
2. The policy file/keystore combination has precedence over a trusted
identity in the identity database.
3. Untrusted identities are ignored in the Java 2 platform.
4. Only trusted identities can be imported into Java 2 SDK keystores.
Keystore Aliases
All keystore entities are accessed via unique aliases.
When using jarsigner to sign a JAR file, you must specify the alias for
the keystore entry containing the private key needed to generate the
signature. For example, the following will sign the JAR file named
MyJARFile.jar, using the private key associated with the alias duke in
the keystore named mystore in the "working" directory. Since no output
file is specified, it overwrites MyJARFile.jar with the signed JAR
file.
jarsigner-keystore /working/mystore -storepass
myspass -keypass dukekeypasswd MyJARFile.jar duke
Keystores are protected with a password, so the store password (in this
case myspass) must be specified. You will be prompted for it if you
don't specify it on the command line. Similarly, private keys are pro‐
tected in a keystore with a password, so the private key's password (in
this case dukekeypasswd) must be specified, and you will be prompted
for it if you don't specify it on the command line and it isn't the
same as the store password.
Keystore Location
jarsigner has a -keystore option for specifying the name and location
of the keystore to be used. The keystore is by default stored in a file
named .keystore in the user's home directory, as determined by the
user.home system property.
Note that the input stream from the -keystore option is passed to the
KeyStore.load method. If NONE is specified as the URL, then a null
stream is passed to the KeyStore.load method. NONE should be specified
if the KeyStore is not file-based, for example, if it resides on a
hardware token device.
Keystore Implementation
The KeyStore class provided in the java.security package supplies well-
defined interfaces to access and modify the information in a keystore.
It is possible for there to be multiple different concrete implementa‐
tions, where each implementation is that for a particular type of key‐
store.
Currently, there are two command-line tools that make use of KeyStore:
keytool and jarsigner, and also a GUI-based tool named policytool.
Since KeyStore is publicly available, JDK users can write additional
security applications that use it.
There is a built-in default implementation, provided by Sun Microsys‐
tems. It implements the keystore as a file, utilizing a proprietary
keystore type (format) named "JKS". It protects each private key with
its individual password, and also protects the integrity of the entire
keystore with a (possibly different) password.
Keystore implementations are provider-based. More specifically, the
application interfaces supplied by KeyStore are implemented in terms of
a "Service Provider Interface" (SPI). That is, there is a corresponding
abstract KeystoreSpi class, also in the java.security package, which
defines the Service Provider Interface methods that "providers" must
implement. (The term "provider" refers to a package or a set of pack‐
ages that supply a concrete implementation of a subset of services that
can be accessed by the Java Security API.) Thus, to provide a keystore
implementation, clients must implement a provider and supply a Key‐
storeSpi subclass implementation, as described in How to Implement a
Provider for the Java Cryptography Architecture.
Applications can choose different types of keystore implementations
from different providers, using the getInstance factory method supplied
in the KeyStore class. A keystore type defines the storage and data
format of the keystore information, and the algorithms used to protect
private keys in the keystore and the integrity of the keystore itself.
Keystore implementations of different types are not compatible.
keytool works on any file-based keystore implementation. (It treats
the keytore location that is passed to it at the command line as a
filename and converts it to a FileInputStream, from which it loads the
keystore information.) The jarsigner and policytool tools, on the other
hand, can read a keystore from any location that can be specified using
a URL.
For jarsigner and keytool, you can specify a keystore type at the com‐
mand line, via the -storetype option. For policytool, you can specify a
keystore type via the "Change Keystore" command in the Edit menu.
If you don't explicitly specify a keystore type, the tools choose a
keystore implementation based simply on the value of the keystore.type
property specified in the security properties file. The security prop‐
erties file is called java.security, and it resides in the security
properties directory, java.home/lib/security, where java.home is the
runtime environment's directory (the jre directory in the SDK or the
top-level directory of the Java 2 Runtime Environment).
Each tool gets the keystore.type value and then examines all the cur‐
rently-installed providers until it finds one that implements keystores
of that type. It then uses the keystore implementation from that
provider.
The KeyStore class defines a static method named getDefaultType that
lets applications and applets retrieve the value of the keystore.type
property. The following line of code creates an instance of the default
keystore type (as specified in the keystore.type property):
KeyStore keyStore = KeyStore.getInstance(KeyStore.getDefault‐
Type());
The default keystore type is "jks" (the proprietary type of the key‐
store implementation provided by Sun). This is specified by the follow‐
ing line in the security properties file:
keystore.type=jks
To have the tools utilize a keystore implementation other than the
default, change that line to specify a different keystore type.
For example, if you have a provider package that supplies a keystore
implementation for a keystore type called "pkcs12", change the line to
keystore.type=pkcs12
Note: case doesn't matter in keystore type designations. For example,
"JKS" would be considered the same as "jks".
Supported Algorithms and Key Sizes
At this time, jarsigner can sign a JAR file using either
· DSA (Digital Signature Algorithm) with the SHA-1 digest algorithm, or
· the RSA algorithm with the MD5 digest algorithm.
That is, if the signer's public and private keys are DSA keys, jar‐
signer will attempt to sign the JAR file using the SHA-1/DSA algorithm.
If the signer's keys are RSA keys, jarsigner will sign the JAR file
using the MD5/RSA algorithm. This is only possible if there is a stati‐
cally installed provider supplying an implementation for the MD5/RSA
algorithm. (There is always a SHA-1/DSA algorithm available, from the
default "SUN" provider.)
The Signed JAR File
When jarsigner is used to sign a JAR file, the output signed JAR file
is exactly the same as the input JAR file, except that it has two addi‐
tional files placed in the META-INF directory:
· a signature file, with a .SF extension, and
· a signature block file, with a .DSA extension.
The base file names for these two files come from the value of the
-sigFile option. For example, if the option appears as
-sigFile MKSIGN
the files are named MKSIGN.SF and MKSIGN.DSA.
If no -sigfile option appears on the command line, the base file name
for the .SF and .DSA files will be the first 8 characters of the alias
name specified on the command line, all converted to upper case. If the
alias name has fewer than 8 characters, the full alias name is used. If
the alias name contains any characters that are not allowed in a signa‐
ture file name, each such character is converted to an underscore ("_")
character in forming the file name. Legal characters include letters,
digits, underscores, and hyphens.
The Signature (.SF) File
A signature file (the .SF file) looks similar to the manifest file that
is always included in a JAR file generated by the jar tool. That is,
for each source file included in the JAR file, the .SF file has three
lines, just as in the manifest file, listing the following:
· the file name,
· the name of the digest algorithm used (SHA), and
· a SHA digest value.
In the manifest file, the SHA digest value for each source file is the
digest (hash) of the binary data in the source file. In the .SF file,
on the other hand, the digest value for a given source file is the hash
of the three lines in the manifest file for the source file.
The signature file also, by default, includes a header containing a
hash of the whole manifest file. The presence of the header enables
verification optimization, as described in JAR File Verification.
The Signature Block (.DSA) File
The .SF file is signed and the signature is placed in the .DSA file.
The .DSA file also contains, encoded inside it, a certificate authenti‐
cating the public key corresponding to the private key used for sign‐
ing.
JAR File Verification
A successful JAR file verification occurs if the signature(s) are
valid, and none of the files that were in the JAR file when the signa‐
tures were generated have been changed since then. JAR file verifica‐
tion involves the following steps:
1. Verify the signature of the .SF file itself.
That is, the verification ensures that the signature stored in
each signature block (.DSA) file was in fact generated using the
private key corresponding to the public key whose certificate also
appears in the .DSA file. It also ensures that the signature is a
valid signature of the corresponding signature (.SF) file, and
thus the .SF file has not been tampered with.
2. Verify the digest listed in each entry in the .SF file with each
corresponding section in the manifest.
The .SF file by default includes a header containing a hash of the
entire manifest file. When the header is present, then the verifi‐
cation can check to see whether or not the hash in the header
indeed matches the hash of the manifest file. If that is the case,
verification proceeds to the next step.
If that is not the case, a less optimized verification is required
to ensure that the hash in each source file information section in
the .SF file equals the hash of its corresponding section in the
manifest file (see The Signature (.SF) File).
One reason the hash of the manifest file that is stored in the .SF
file header may not equal the hash of the current manifest file
would be because one or more files were added to the JAR file
(using the jar tool) after the signature (and thus the .SF file)
was generated. When the jar tool is used to add files, the mani‐
fest file is changed (sections are added to it for the new files),
but the .SF file is not. A verification is still considered suc‐
cessful if none of the files that were in the JAR file when the
signature was generated have been changed since then, which is the
case if the hashes in the non-header sections of the .SF file
equal the hashes of the corresponding sections in the manifest
file.
3. Read each file in the JAR file that has an entry in the .SF file.
While reading, compute the file's digest, and then compare the
result with the digest for this file in the manifest section. The
digests should be the same, or verification fails.
If any serious verification failures occur during the verification
process, the process is stopped and a security exception is thrown. It
is caught and displayed by jarsigner.
Multiple Signatures for a JAR File
A JAR file can be signed by multiple people simply by running the jar‐
signer tool on the file multiple times, specifying the alias for a dif‐
ferent person each time, as in:
jarsigner myBundle.jar susan
jarsigner myBundle.jar kevin
When a JAR file is signed multiple times, there are multiple .SF and
.DSA files in the resulting JAR file, one pair for each signature.
Thus, in the example above, the output JAR file includes files with the
following names:
SUSAN.SF
SUSAN.DSA
KEVIN.SF
KEVIN.DSA
Note: It is also possible for a JAR file to have mixed signatures, some
generated by the JDK 1.1 javakey tool and others by jarsigner. That is,
jarsigner can be used to sign JAR files already previously signed using
javakey.
OPTIONS
The various jarsigner options are listed and described below. Note:
· All option names are preceded by a minus sign (-).
· The options may be provided in any order.
· Items in italics (option values) represent the actual values that
must be supplied.
· The -keystore, -storepass, -keypass, -sigfile, and -signedjar options
are only relevant when signing a JAR file, not when verifying a
signed JAR file. Similarly, an alias is only specified on the command
line when signing a JAR file.
-keystore url Specifies the URL that tells the keystore location. This
defaults to the file .keystore in the user's home direc‐
tory, as determined by the user.home system property.
A keystore is required when signing, so you must explic‐
itly specify one if the default keystore does not exist
(or you want to use one other than the default).
A keystore is not required when verifying, but if one is
specified, or the default exists, and the -verbose
option was also specified, additional information is
output regarding whether or not any of the certificates
used to verify the JAR file are contained in that key‐
store.
Note: the -keystore argument can actually be a file name
(and path) specification rather than a URL, in which
case it will be treated the same as a "file:" URL. That
is,
-keystore filePathAndName
is treated as equivalent to
-keystore file:filePathAndName
-storetype storetype
Specifies the type of keystore to be instantiated. The
default keystore type is the one that is specified as
the value of the "keystore.type" property in the secu‐
rity properties file, which is returned by the static
getDefaultType method in java.security.KeyStore.
-storepass password
Specifies the password which is required to access the
keystore. This is only needed when signing (not verify‐
ing) a JAR file. In that case, if a -storepass option is
not provided at the command line, the user is prompted
for the password.
Note: The password shouldn't be specified on the command
line or in a script unless it is for testing purposes,
or you are on a secure system. Also, when typing in a
password at the password prompt, the password is echoed
(displayed exactly as typed), so be careful not to type
it in front of anyone.
-keypass password
Specifies the password used to protect the private key
of the keystore entry addressed by the alias specified
on the command line. The password is required when using
jarsigner to sign a JAR file. If no password is provided
on the command line, and the required password is dif‐
ferent from the store password, the user is prompted for
it.
Note: The password shouldn't be specified on the command
line or in a script unless it is for testing purposes,
or you are on a secure system. Also, when typing in a
password at the password prompt, the password is echoed
(displayed exactly as typed), so be careful not to type
it in front of anyone.
-sigfile file Specifies the base file name to be used for the gener‐
ated .SF and .DSA files. For example, if file is DUKE‐
SIGN, the generated .SF and .DSA files will be named
DUKESIGN.SF and DUKESIGN.DSA, and will be placed in the
META-INF directory of the signed JAR file.
The characters in file must come from the set "a-zA-
Z0-9_-". That is, only letters, numbers, underscore,
and hyphen characters are allowed. Note: All lowercase
characters will be converted to uppercase for the .SF
and .DSA file names.
If no -sigfile option appears on the command line, the
base file name for the .SF and .DSA files will be the
first 8 characters of the alias name specified on the
command line, all converted to upper case. If the alias
name has fewer than 8 characters, the full alias name is
used. If the alias name contains any characters that
are not legal in a signature file name, each such char‐
acter is converted to an underscore ("_") character in
forming the file name.
-signedjar file
Specifies the name to be used for the signed JAR file.
If no name is specified on the command line, the name
used is the same as the input JAR file name (the name of
the JAR file to be signed); in other words, that file is
overwritten with the signed JAR file.
-verify If this appears on the command line, the specified JAR
file will be verified, not signed. If the verification
is successful, "jar verified" will be displayed. If you
try to verify an unsigned JAR file, or a JAR file signed
with an unsupported algorithm (for example, RSA when you
don't have an RSA provider installed), the following is
displayed: "jar is unsigned. (signatures missing or not
parsable)"
It is possible to verify JAR files signed using either
jarsigner or the JDK 1.1 javakey tool, or both.
For further information on verification, see JAR File
Verification.
-certs If this appears on the command line, along with the
-verify and -verbose options, the output includes cer‐
tificate information for each signer of the JAR file.
This information includes:
· the name of the type of certificate (stored in the
.DSA file) that certifies the signer's public key
· if the certificate is an X.509 certificate (more
specifically, an instance of java.secu‐
rity.cert.X509Certificate): the distinguished name of
the signer
The keystore is also examined. If no keystore value is
specified on the command line, the default keystore file
(if any) will be checked. If the public key certificate
for a signer matches an entry in the keystore, then the
following information will also be displayed:
· in parentheses, the alias name for the keystore entry
for that signer. If the signer actually comes from a
JDK 1.1 identity database instead of from a keystore,
the alias name will appear in brackets instead of
parentheses.
-verbose If this appears on the command line, it indicates "ver‐
bose" mode, which causes jarsigner to output extra
information as to the progress of the JAR signing or
verification.
-internalsf In the past, the .DSA (signature block) file generated
when a JAR file was signed used to include a complete
encoded copy of the .SF file (signature file) also gen‐
erated. This behavior has been changed. To reduce the
overall size of the output JAR file, the .DSA file by
default doesn't contain a copy of the .SF file anymore.
But if -internalsf appears on the command line, the old
behavior is utilized. This option is mainly useful for
testing; in practice, it should not be used, since doing
so eliminates a useful optimization.
-sectionsonly If this appears on the command line, the .SF file (sig‐
nature file) generated when a JAR file is signed does
not include a header containing a hash of the whole man‐
ifest file. It just contains information and hashes
related to each individual source file included in the
JAR file, as described in The Signature (.SF) File .
By default, this header is added, as an optimization.
When the header is present, then whenever the JAR file
is verified, the verification can first check to see
whether or not the hash in the header indeed matches the
hash of the whole manifest file. If so, verification
proceeds to the next step. If not, it is necessary to do
a less optimized verification that the hash in each
source file information section in the .SF file equals
the hash of its corresponding section in the manifest
file.
For further information, see JAR File Verification.
This option is mainly useful for testing; in practice,
it should not be used, since doing so eliminates a use‐
ful optimization.
-provider provider_class_name
Used to specify the name of the cryptographic service
provider's master class file when the service provider
is not listed in the security properties file.
-Jjavaoption Passes the specified javaoption string directly to the
runtime system. (jarsigner is actually a "wrapper"
around the interpreter.) This option should not contain
any spaces. It is useful for adjusting the execution
environment or memory usage. For a list of possible
flags, type java -h or java -X at the command line.
EXAMPLES
Signing a JAR File
Suppose you have a JAR file named bundle.jar and you'd like to sign it
using the private key of the user whose keystore alias is "jane" in the
keystore named "mystore" in the "working" directory. Suppose the key‐
store password is "myspass" and the password for jane's private key is
"j638klm". You can use the following to sign the JAR file and name the
signed JAR file "sbundle.jar":
jarsigner-keystore "/working/mystore" -storepass myspass
-keypass j638klm -signedjar sbundle.jar bundle.jar jane
Note that there is no -sigfile specified in the command above, so the
generated .SF and .DSA files to be placed in the signed JAR file will
have default names based on the alias name. That is, they will be named
JANE.SF and JANE.DSA.
If you want to be prompted for the store password and the private key
password, you could shorten the above command to
jarsigner-keystore /working/mystore
-signedjar sbundle.jar bundle.jar jane
If the keystore to be used is the default keystore (the one named .key‐
store in your home directory), you don't need to specify a keystore, as
in:
jarsigner-signedjar sbundle.jar bundle.jar jane
Finally, if you want the signed JAR file to simply overwrite the input
JAR file (bundle.jar), you don't need to specify a -signedjar option:
jarsigner bundle.jar jane
Verifying a Signed JAR File
To verify a signed JAR file, that is, to verify that the signature is
valid and the JAR file has not been tampered with, use a command such
as the following:
jarsigner-verify sbundle.jar
If the verification is successful,
jar verified.
is displayed. Otherwise, an error message appears.
You can get more information if you use the -verbose option. A sample
use of jarsigner with the -verbose option is shown below, along with
sample output:
jarsigner-verify -verbose sbundle.jar
198 Fri Sep 26 16:14:06 PDT 1997 META-INF/MANIFEST.MF
199 Fri Sep 26 16:22:10 PDT 1997 META-INF/JANE.SF
1013 Fri Sep 26 16:22:10 PDT 1997 META-INF/JANE.DSA
smk 2752 Fri Sep 26 16:12:30 PDT 1997 AclEx.class
smk 849 Fri Sep 26 16:12:46 PDT 1997 test.class
s = signature was verified
m = entry is listed in manifest
k = at least one certificate was found in keystore
jar verified.
Verification with Certificate Information
If you specify the -certs option when verifying, along with the -verify
and -verbose options, the output includes certificate information for
each signer of the JAR file, including the certificate type, the signer
distinguished name information (if it's an X.509 certificate), and, in
parentheses, the keystore alias for the signer if the public key cer‐
tificate in the JAR file matches that in a keystore entry. For example,
example% jarsigner-keystore /working/mystore -verify -verbose -certs myTest.jar
198 Fri Sep 26 16:14:06 PDT 1997 META-INF/MANIFEST.MF
199 Fri Sep 26 16:22:10 PDT 1997 META-INF/JANE.SF
1013 Fri Sep 26 16:22:10 PDT 1997 META-INF/JANE.DSA
208 Fri Sep 26 16:23:30 PDT 1997 META-INF/JAVATEST.SF
1087 Fri Sep 26 16:23:30 PDT 1997 META-INF/JAVATEST.DSA
smk 2752 Fri Sep 26 16:12:30 PDT 1997 Tst.class
X.509, CN=Test Group, OU=Java Software, O=Sun Microsystems, L=CUP, S=CA, C=US (javatest)
X.509, CN=Jane Smith, OU=Java Software, O=Sun, L=cup, S=ca, C=us (jane)
s = signature was verified
m = entry is listed in manifest
k = at least one certificate was found in keystore
jar verified.
If the certificate for a signer is not an X.509 certificate, there is
no distinguished name information. In that case, just the certificate
type and the alias are shown. For example, if the certificate is a PGP
certificate, and the alias is "bob", you'd get
PGP, (bob)
Verification of a JAR File that Includes Idnetity Database Signers
If a JAR file has been signed using the JDK 1.1 javakey tool, and thus
the signer is an alias in an identity database, the verification output
includes an "i" symbol. If the JAR file has been signed by both an
alias in an identity database and an alias in a keystore, both "k" and
"i" appear.
When the -certs option is used, any identity database aliases are shown
in square brackets rather than the parentheses used for keystore
aliases. For example:
jarsigner-keystore /working/mystore -verify -verbose -certs writeFile.jar
198 Fri Sep 26 16:14:06 PDT 1997 META-INF/MANIFEST.MF
199 Fri Sep 26 16:22:10 PDT 1997 META-INF/JANE.SF
1013 Fri Sep 26 16:22:10 PDT 1997 META-INF/JANE.DSA
199 Fri Sep 27 12:22:30 PDT 1997 META-INF/DUKE.SF
1013 Fri Sep 27 12:22:30 PDT 1997 META-INF/DUKE.DSA
smki 2752 Fri Sep 26 16:12:30 PDT 1997 writeFile.html
X.509, CN=Jane Smith, OU=Java Software, O=Sun, L=cup, S=ca, C=us (jane)
X.509, CN=Duke, OU=Java Software, O=Sun, L=cup, S=ca, C=us [duke]
s = signature was verified
m = entry is listed in manifest
k = at least one certificate was found in keystore
i = at least one certificate was found in identity scope
jar verified.
Note that the alias "duke" is in brackets to denote that it is an iden‐
tity database alias, not a keystore alias.
SEE ALSOjar(1), keytool(1)
23 Jun 2004 jarsigner(1)