TS(1SSL) OpenSSL TS(1SSL)NAMEts - Time Stamping Authority tool (client/server)
SYNOPSIS
openssl ts-query [-rand file:file...] [-config configfile] [-data
file_to_hash] [-digest digest_bytes]
[-md2|-md4|-md5|-sha|-sha1|-mdc2|-ripemd160|...] [-policy object_id]
[-no_nonce] [-cert] [-in request.tsq] [-out request.tsq] [-text]
openssl ts-reply [-config configfile] [-section tsa_section]
[-queryfile request.tsq] [-passin password_src] [-signer tsa_cert.pem]
[-inkey private.pem] [-chain certs_file.pem] [-policy object_id] [-in
response.tsr] [-token_in] [-out response.tsr] [-token_out] [-text]
[-engine id]
openssl ts-verify [-data file_to_hash] [-digest digest_bytes]
[-queryfile request.tsq] [-in response.tsr] [-token_in] [-CApath
trusted_cert_path] [-CAfile trusted_certs.pem] [-untrusted
cert_file.pem]
DESCRIPTION
The ts command is a basic Time Stamping Authority (TSA) client and
server application as specified in RFC 3161 (Time-Stamp Protocol, TSP).
A TSA can be part of a PKI deployment and its role is to provide long
term proof of the existence of a certain datum before a particular
time. Here is a brief description of the protocol:
1. The TSA client computes a one-way hash value for a data file and
sends the hash to the TSA.
2. The TSA attaches the current date and time to the received hash
value, signs them and sends the time stamp token back to the
client. By creating this token the TSA certifies the existence of
the original data file at the time of response generation.
3. The TSA client receives the time stamp token and verifies the
signature on it. It also checks if the token contains the same hash
value that it had sent to the TSA.
There is one DER encoded protocol data unit defined for transporting a
time stamp request to the TSA and one for sending the time stamp
response back to the client. The ts command has three main functions:
creating a time stamp request based on a data file, creating a time
stamp response based on a request, verifying if a response corresponds
to a particular request or a data file.
There is no support for sending the requests/responses automatically
over HTTP or TCP yet as suggested in RFC 3161. The users must send the
requests either by ftp or e-mail.
OPTIONS
Time Stamp Request generation
The -query switch can be used for creating and printing a time stamp
request with the following options:
-rand file:file...
The files containing random data for seeding the random number
generator. Multiple files can be specified, the separator is ; for
MS-Windows, , for VMS and : for all other platforms. (Optional)
-config configfile
The configuration file to use, this option overrides the
OPENSSL_CONF environment variable. Only the OID section of the
config file is used with the -query command. (Optional)
-data file_to_hash
The data file for which the time stamp request needs to be created.
stdin is the default if neither the -data nor the -digest parameter
is specified. (Optional)
-digest digest_bytes
It is possible to specify the message imprint explicitly without
the data file. The imprint must be specified in a hexadecimal
format, two characters per byte, the bytes optionally separated by
colons (e.g. 1A:F6:01:... or 1AF601...). The number of bytes must
match the message digest algorithm in use. (Optional)
-md2|-md4|-md5|-sha|-sha1|-mdc2|-ripemd160|...
The message digest to apply to the data file, it supports all the
message digest algorithms that are supported by the openssl dgst
command. The default is SHA-1. (Optional)
-policy object_id
The policy that the client expects the TSA to use for creating the
time stamp token. Either the dotted OID notation or OID names
defined in the config file can be used. If no policy is requested
the TSA will use its own default policy. (Optional)
-no_nonce
No nonce is specified in the request if this option is given.
Otherwise a 64 bit long pseudo-random none is included in the
request. It is recommended to use nonce to protect against replay-
attacks. (Optional)
-cert
The TSA is expected to include its signing certificate in the
response. (Optional)
-in request.tsq
This option specifies a previously created time stamp request in
DER format that will be printed into the output file. Useful when
you need to examine the content of a request in human-readable
format. (Optional)
-out request.tsq
Name of the output file to which the request will be written.
Default is stdout. (Optional)
-text
If this option is specified the output is human-readable text
format instead of DER. (Optional)
Time Stamp Response generation
A time stamp response (TimeStampResp) consists of a response status and
the time stamp token itself (ContentInfo), if the token generation was
successful. The -reply command is for creating a time stamp response or
time stamp token based on a request and printing the response/token in
human-readable format. If -token_out is not specified the output is
always a time stamp response (TimeStampResp), otherwise it is a time
stamp token (ContentInfo).
-config configfile
The configuration file to use, this option overrides the
OPENSSL_CONF environment variable. See CONFIGURATION FILE OPTIONS
for configurable variables. (Optional)
-section tsa_section
The name of the config file section conatining the settings for the
response generation. If not specified the default TSA section is
used, see CONFIGURATION FILE OPTIONS for details. (Optional)
-queryfile request.tsq
The name of the file containing a DER encoded time stamp request.
(Optional)
-passin password_src
Specifies the password source for the private key of the TSA. See
PASS PHRASE ARGUMENTS in openssl(1). (Optional)
-signer tsa_cert.pem
The signer certificate of the TSA in PEM format. The TSA signing
certificate must have exactly one extended key usage assigned to
it: timeStamping. The extended key usage must also be critical,
otherwise the certificate is going to be refused. Overrides the
signer_cert variable of the config file. (Optional)
-inkey private.pem
The signer private key of the TSA in PEM format. Overrides the
signer_key config file option. (Optional)
-chain certs_file.pem
The collection of certificates in PEM format that will all be
included in the response in addition to the signer certificate if
the -cert option was used for the request. This file is supposed to
contain the certificate chain for the signer certificate from its
issuer upwards. The -reply command does not build a certificate
chain automatically. (Optional)
-policy object_id
The default policy to use for the response unless the client
explicitly requires a particular TSA policy. The OID can be
specified either in dotted notation or with its name. Overrides the
default_policy config file option. (Optional)
-in response.tsr
Specifies a previously created time stamp response or time stamp
token (if -token_in is also specified) in DER format that will be
written to the output file. This option does not require a request,
it is useful e.g. when you need to examine the content of a
response or token or you want to extract the time stamp token from
a response. If the input is a token and the output is a time stamp
response a default 'granted' status info is added to the token.
(Optional)
-token_in
This flag can be used together with the -in option and indicates
that the input is a DER encoded time stamp token (ContentInfo)
instead of a time stamp response (TimeStampResp). (Optional)
-out response.tsr
The response is written to this file. The format and content of the
file depends on other options (see -text, -token_out). The default
is stdout. (Optional)
-token_out
The output is a time stamp token (ContentInfo) instead of time
stamp response (TimeStampResp). (Optional)
-text
If this option is specified the output is human-readable text
format instead of DER. (Optional)
-engine id
Specifying an engine (by its unique id string) will cause ts to
attempt to obtain a functional reference to the specified engine,
thus initialising it if needed. The engine will then be set as the
default for all available algorithms. Default is builtin.
(Optional)
Time Stamp Response verification
The -verify command is for verifying if a time stamp response or time
stamp token is valid and matches a particular time stamp request or
data file. The -verify command does not use the configuration file.
-data file_to_hash
The response or token must be verified against file_to_hash. The
file is hashed with the message digest algorithm specified in the
token. The -digest and -queryfile options must not be specified
with this one. (Optional)
-digest digest_bytes
The response or token must be verified against the message digest
specified with this option. The number of bytes must match the
message digest algorithm specified in the token. The -data and
-queryfile options must not be specified with this one. (Optional)
-queryfile request.tsq
The original time stamp request in DER format. The -data and
-digest options must not be specified with this one. (Optional)
-in response.tsr
The time stamp response that needs to be verified in DER format.
(Mandatory)
-token_in
This flag can be used together with the -in option and indicates
that the input is a DER encoded time stamp token (ContentInfo)
instead of a time stamp response (TimeStampResp). (Optional)
-CApath trusted_cert_path
The name of the directory containing the trused CA certificates of
the client. See the similar option of verify(1) for additional
details. Either this option or -CAfile must be specified.
(Optional)
-CAfile trusted_certs.pem
The name of the file containing a set of trusted self-signed CA
certificates in PEM format. See the similar option of verify(1) for
additional details. Either this option or -CApath must be
specified. (Optional)
-untrusted cert_file.pem
Set of additional untrusted certificates in PEM format which may be
needed when building the certificate chain for the TSA's signing
certificate. This file must contain the TSA signing certificate and
all intermediate CA certificates unless the response includes them.
(Optional)
CONFIGURATION FILE OPTIONS
The -query and -reply commands make use of a configuration file defined
by the OPENSSL_CONF environment variable. See config(5) for a general
description of the syntax of the config file. The -query command uses
only the symbolic OID names section and it can work without it.
However, the -reply command needs the config file for its operation.
When there is a command line switch equivalent of a variable the switch
always overrides the settings in the config file.
tsa section, default_tsa
This is the main section and it specifies the name of another
section that contains all the options for the -reply command. This
default section can be overridden with the -section command line
switch. (Optional)
oid_file
See ca(1) for description. (Optional)
oid_section
See ca(1) for description. (Optional)
RANDFILE
See ca(1) for description. (Optional)
serial
The name of the file containing the hexadecimal serial number of
the last time stamp response created. This number is incremented by
1 for each response. If the file does not exist at the time of
response generation a new file is created with serial number 1.
(Mandatory)
crypto_device
Specifies the OpenSSL engine that will be set as the default for
all available algorithms. The default value is builtin, you can
specify any other engines supported by OpenSSL (e.g. use chil for
the NCipher HSM). (Optional)
signer_cert
TSA signing certificate in PEM format. The same as the -signer
command line option. (Optional)
certs
A file containing a set of PEM encoded certificates that need to be
included in the response. The same as the -chain command line
option. (Optional)
signer_key
The private key of the TSA in PEM format. The same as the -inkey
command line option. (Optional)
default_policy
The default policy to use when the request does not mandate any
policy. The same as the -policy command line option. (Optional)
other_policies
Comma separated list of policies that are also acceptable by the
TSA and used only if the request explicitly specifies one of them.
(Optional)
digests
The list of message digest algorithms that the TSA accepts. At
least one algorithm must be specified. (Mandatory)
accuracy
The accuracy of the time source of the TSA in seconds, milliseconds
and microseconds. E.g. secs:1, millisecs:500, microsecs:100. If any
of the components is missing zero is assumed for that field.
(Optional)
clock_precision_digits
Specifies the maximum number of digits, which represent the
fraction of seconds, that need to be included in the time field.
The trailing zeroes must be removed from the time, so there might
actually be fewer digits, or no fraction of seconds at all.
Supported only on UNIX platforms. The maximum value is 6, default
is 0. (Optional)
ordering
If this option is yes the responses generated by this TSA can
always be ordered, even if the time difference between two
responses is less than the sum of their accuracies. Default is no.
(Optional)
tsa_name
Set this option to yes if the subject name of the TSA must be
included in the TSA name field of the response. Default is no.
(Optional)
ess_cert_id_chain
The SignedData objects created by the TSA always contain the
certificate identifier of the signing certificate in a signed
attribute (see RFC 2634, Enhanced Security Services). If this
option is set to yes and either the certs variable or the -chain
option is specified then the certificate identifiers of the chain
will also be included in the SigningCertificate signed attribute.
If this variable is set to no, only the signing certificate
identifier is included. Default is no. (Optional)
ENVIRONMENT VARIABLES
OPENSSL_CONF contains the path of the configuration file and can be
overridden by the -config command line option.
EXAMPLES
All the examples below presume that OPENSSL_CONF is set to a proper
configuration file, e.g. the example configuration file
openssl/apps/openssl.cnf will do.
Time Stamp Request
To create a time stamp request for design1.txt with SHA-1 without nonce
and policy and no certificate is required in the response:
openssl ts-query -data design1.txt -no_nonce \
-out design1.tsq
To create a similar time stamp request with specifying the message
imprint explicitly:
openssl ts-query -digest b7e5d3f93198b38379852f2c04e78d73abdd0f4b \
-no_nonce -out design1.tsq
To print the content of the previous request in human readable format:
openssl ts-query -in design1.tsq -text
To create a time stamp request which includes the MD-5 digest of
design2.txt, requests the signer certificate and nonce, specifies a
policy id (assuming the tsa_policy1 name is defined in the OID section
of the config file):
openssl ts-query -data design2.txt -md5 \
-policy tsa_policy1 -cert -out design2.tsq
Time Stamp Response
Before generating a response a signing certificate must be created for
the TSA that contains the timeStamping critical extended key usage
extension without any other key usage extensions. You can add the
'extendedKeyUsage = critical,timeStamping' line to the user certificate
section of the config file to generate a proper certificate. See
req(1), ca(1), x509(1) for instructions. The examples below assume that
cacert.pem contains the certificate of the CA, tsacert.pem is the
signing certificate issued by cacert.pem and tsakey.pem is the private
key of the TSA.
To create a time stamp response for a request:
openssl ts-reply -queryfile design1.tsq -inkey tsakey.pem \
-signer tsacert.pem -out design1.tsr
If you want to use the settings in the config file you could just
write:
openssl ts-reply -queryfile design1.tsq -out design1.tsr
To print a time stamp reply to stdout in human readable format:
openssl ts-reply -in design1.tsr -text
To create a time stamp token instead of time stamp response:
openssl ts-reply -queryfile design1.tsq -out design1_token.der -token_out
To print a time stamp token to stdout in human readable format:
openssl ts-reply -in design1_token.der -token_in -text -token_out
To extract the time stamp token from a response:
openssl ts-reply -in design1.tsr -out design1_token.der -token_out
To add 'granted' status info to a time stamp token thereby creating a
valid response:
openssl ts-reply -in design1_token.der -token_in -out design1.tsr
Time Stamp Verification
To verify a time stamp reply against a request:
openssl ts-verify -queryfile design1.tsq -in design1.tsr \
-CAfile cacert.pem -untrusted tsacert.pem
To verify a time stamp reply that includes the certificate chain:
openssl ts-verify -queryfile design2.tsq -in design2.tsr \
-CAfile cacert.pem
To verify a time stamp token against the original data file:
openssl ts-verify -data design2.txt -in design2.tsr \ -CAfile
cacert.pem
To verify a time stamp token against a message imprint:
openssl ts-verify -digest b7e5d3f93198b38379852f2c04e78d73abdd0f4b \
-in design2.tsr -CAfile cacert.pem
You could also look at the 'test' directory for more examples.
BUGS
If you find any bugs or you have suggestions please write to Zoltan
Glozik <zglozik@opentsa.org>. Known issues:
· No support for time stamps over SMTP, though it is quite easy to
implement an automatic e-mail based TSA with procmail(1) and
perl(1). HTTP server support is provided in the form of a separate
apache module. HTTP client support is provided by tsget(1). Pure
TCP/IP protocol is not supported.
· The file containing the last serial number of the TSA is not locked
when being read or written. This is a problem if more than one
instance of openssl(1) is trying to create a time stamp response at
the same time. This is not an issue when using the apache server
module, it does proper locking.
· Look for the FIXME word in the source files.
· The source code should really be reviewed by somebody else, too.
· More testing is needed, I have done only some basic tests (see
test/testtsa).
AUTHOR
Zoltan Glozik <zglozik@opentsa.org>, OpenTSA project
(http://www.opentsa.org)
SEE ALSOtsget(1), openssl(1), req(1), x509(1), ca(1), genrsa(1), config(5)1.0.1f 2014-04-07 TS(1SSL)
