O-Saft/Documentation

From OWASP
Jump to: navigation, search

O-Saft

This is O-Saft's documentation as you get with:

o-saft.pl --help

On Windows following must be used

o-saft.pl --help --v


NAME

o-saft.pl - OWASP SSL advanced forensic tool
OWASP SSL audit for testers

DESCRIPTION

This tools lists information about remote target's SSL certificate
and tests the remote target according given list of ciphers.
Note: Throughout this description $0 is used as an alias for the
program name o-saft.pl .

SYNOPSIS

 o-saft.pl [COMMANDS ..] [OPTIONS ..] target [target target ...]
Where [COMMANDS] and [OPTIONS] are described below and target
is a hostname either as full qualified domain name or as IP address.
Multiple commands and targets may be combined.
All commands and options can also be specified in a rc-file, see
RC-FILE below.

QUICKSTART

Before going into a detailed description of the purpose and usage,
here are some examples of the most common use cases:
  • Show supported (enabled) ciphers of target:
   o-saft.pl +cipher --enabled example.tld
  • Show supported (enabled) ciphers with their DH parameters:
   o-saft.pl +cipher-dh example.tld
  • Test all ciphers, even if not supported by local SSL implementation:
   o-saft.pl +cipherall example.tld
  • Show details of certificate and connection of target:
   o-saft.pl +info example.tld
  • Check certificate, ciphers and SSL connection of target:
   o-saft.pl +check example.tld
  • Check connection to target for vulnerabilities:
   o-saft.pl +vulns example.tld
  • Check for all known ciphers (independant of SSL library):
   o-saft.pl example.tld --range=full
   checkAllCiphers.pl example.tld
   checkAllCiphers.pl example.tld --range=full --v
  • Get the certificate's Common Name for a bunch of servers:
   o-saft.pl +cn example.tld some.tld other.tld
  • List more usage examples
   o-saft.pl --help=examples
  • List all available commands:
   o-saft.pl --help=commands
  • Get table of contents for complete help
   o-saft.pl --help=toc
  • Show just one section, for example SECURITY, from help
   o-saft.pl --help=SECURITY
  • Start the simple GUI
   o-saft.tcl
For more specialised test cases, refer to the COMMANDS and OPTIONS
sections below. For more examples please refer to EXAMPLES section.
For more details, please see INSTALLATION below.

WHY?

Why a new tool for checking SSL security and configuration when there
are already a dozen or more such good tools in existence (circa 2012)?
Unique features:
  • working in closed environments, i.e. without internet connection
  • checking availability of ciphers independent of installed library
  • checking for all possible ciphers (up to 65535 per SSL protocol)
  • mainly same results on all platforms.
Currently available tools suffer from some or all of following issues:
  • lack of tests of unusual SSL certificate configurations
  • may return different results for the same checks on a given target
  • missing tests for modern SSL/TLS functionality
  • missing tests for specific, known SSL/TLS vulnerabilities
  • no support for newer, advanced, features e.g. CRL, OCSP, EV
  • limited capability to create your own customised tests
Other reasons or problems are that other tools are either binary or
use additional binaries and hence not portable to other platforms.
In contrast to (all?) most other tools, including openssl, it can be
used to `ask simple questions' like `does target support STS' just by
calling:
   o-saft.pl +hsts_sts example.tld
For more, please see EXAMPLES section below.

SECURITY

This tool is designed to be used by people doing security or forensic
analyses. Hence no malicious input is expected.
There are no special security checks implemented. Some parameters are
roughly sanatised according unwanted characters. In particular there
are no checks according any kind of code injection.
Care should be taken, when additional tools and modules are installed
as described in INSTALLATION below. In particular we recommend to
do such installations into directoies specially prepared for use with
o-saft.pl . No other tools of your system should use these installations
i.e. by accident or because your environment variables point to them.
Note that compilation and installation of additional tools (openssl,
Net::SSLeay, etc.) uses known insecure configurations and features!
This is essential to make o-saft.pl able to check for such insecurities.
It is highly recommended to do these installations and use the tools
on a separate testing system.
DO NOT USE THESE INSTALLATIONS ON PRODUCTIVE SYTEMS.

TECHNICAL INFORMATION

It is important to understand, which provided information is based on
data returned by underlaying (used) libraries and the information
computed directly.
OpenSSL, libssl, libcrypto
In general the tool uses perl's Net::SSLeay(1) module which itself
is based on libssl and/or libssleay library of the operating system.
It's possible to use other versions of these libraries, see options:
  • --exe-path=PATH --exe=PATH
  • --lib-path=PATH --lib=PATH
  • --envlibvar=NAME
The external openssl(1) is called to extract some information from
its output. The version of openssl can be controlled with following
options:
  • --openssl=TOOL
  • --no-openssl
  • --force-openssl
  • --exe-path=PATH --exe=PATH
Above applies to all commands except +cipherall which uses no other
libraries.
OpenSSL is recommended to be used for libssl and libcrypto. Versions
0.9.8k to 1.0.2e (Jan. 2016) are known to work. However, versions be-
for 1.0.0 may not provide all informations.
LibreSSL is not recommended, because some functionallity considered
insecure, has been removed.
For more details, please see INSTALLATION below.
Certificates and CA
All checks according the validity of the certificate chain are based
on the root CAs installed on the system. NOTE that Net::SSLeay(1)
and openssl(1) may have their own rules how and where to find the
root CAs. Please refer to the documentation on your system for these
tools. However, there are folloing options to tweak these rules:
  • --ca-file=FILE
  • --ca-path=DIR
  • --ca-depth=INT
Commands and options
All arguments starting with + are considered COMMANDS for this
tool. All arguments starting with -- are considered OPTIONS for
this tool.
Reading any data from STDIN or here-documents is not yet supported.
It's reserved for future use.
Environment variables
Following environment variables are incorporated:
  • OPENSSL - if set, full path to openssl executable
  • OPENSSL_CONF - if set, full path to openssl's openssl.cnf or
directory where to find openssl.cnf
  • LD_LIBRARY_PATH - used and extended with definitions from options
Requirements
For checking all ciphers and all protocols with +cipherall command,
just perl (5.x) without any modules is required.
For +info and +check (and all related) commands, perl (5.x) with
following modules (minimal version) is required:
  • IO 1.25 (2011)
  • IO::Socket:SSL 1.37 (2011)
  • IO::Socket:SSL 1.90 (2013)
  • Net::DNS 0.66 (2011)
  • Net::SSLeay 1.49 (2012)
However, it is recommended to use the most recent version of the mod-
ules which then gives more accurate results and less warnings. Also
an openssl(1) executable should be available, but is not mandatory.
For checking DH parameters of ciphers, openssl 1.0.2 or newer should
be available. If an older version of openssl is found, we try hard to
extract the DH parameters from the data returned by the server.

RESULTS

All output is designed to make be easily parsed by postprocessors. Please
see OUTPUT section below for details.
For the results, we have to distinguish those returned by +cipher
command and those from all other tests and checks like +check or
+info command.
+cipher
The cipher checks will return one line for each tested cipher. It
contains at least the cipher name, yes or no whether it's
supported or not, and a security qualification. It may look like:
   AES256-SHA       yes    HIGH
   NULL-SHA         no     weak
Depending on the used --legacy=* option the format may differ
and also contain more information. For details see --legacy=*
option below.
The text for security qualifications are mainly those returned by
openssl (version 1.0.1): LOW, MEDIUM, HIGH and WEAK.
The same texts but with all lower case characters are used if the
qualification was adapted herein. Following rules for adjusting the
qualification were used:
  • weak:
    • all *NULL* ciphers
    • all *RC4* ciphers
    • all *EXPORT* ciphers
    • all *anon* (aka ADH aka DHA) ciphers
  • low:
    • all *CBC* ciphers
  • high:
    • all *CBC3* (aka 3DES) ciphers
    • all *AES(128|256)* ciphers
    • all *CAMELLIA* ciphers
+check
These tests return a line with a label describing the test and a
test result for it. The idea is to report yes if the result
is considered "secure" and report the reason why it is considered
insecure otherwise. Example of a check considered secure:
       Label of the performed check:           yes
Example of a check considered insecure:
       Label of the performed check:           no (reason why)
Note that there are tests where the results appear confusing when
first viewed, like for www.wi.ld:
       Certificate is valid according given hostname:  no (*.wi.ld)
       Certificate's wildcard does not match hostname: yes
This can for example occur with:
       Certificate Common Name:                *.wi.ld
       Certificate Subject's Alternate Names:  DNS:www.wi.ld
Please check the result with the +info command also to verify
if the check sounds reasonable.
+info
The test result contains detailed information. The labels there
are mainly the same as for the "+check" command.

COMMANDS

There are commands for various tests according the SSL connection to
the target, the targets certificate and the used ciphers.
All commands are preceded by a + to easily distinguish from other
arguments and options. However, some --OPT options are treated as
commands for historical reason or compatibility to other programs.
The most important commands are (in alphabetical order):
+check +cipher +info +http +list +quick +sni +sni_check +version
A list of all available commands will be printed with
   o-saft.pl --help=cmd
The description of all other commands will be printed with
   o-saft.pl --header --help=commands
The summary and internal commands return requested information or the
results of checks. These are described below.
Note that some commands may be a combination of other commands, see:
   o-saft.pl --header --help=intern
The following sub-sections only describe the commands, which do more
than giving a simple information from the target. All other commands
can be listed with:
   $0 --header --help=commands
The final sub-sections Notes about commands describes some notes
about special commands and related commands.
Commands for information about this tool
All these commands will exit after execution (cannot be used together
with other commands).
+ciphers
Show ciphers offered by local SSL implementation.
This commands prints the ciphers in format like openssl ciphers
does. It also accepts the -v and -V option. The --legacy=TYPE
option can be used as described for +list command.
Use +list command for more information according ciphers.
+list
Show all ciphers known by this tool. This includes cryptogrphic
details of the cipher and some internal details about the rating.
In contrast to +ciphers command +list uses TAB characters
instead of spaces to seperate columns. It also prints table header
lines by default.
Different output formats are used for the --legacy option:
  • --legacy=simple - tabular output of cipher values
  • --legacy=full - as --legacy=simple but more data
  • --legacy=openssl - output like with +cipher command
  • --legacy=ssltest - output like ssltest --list
+VERSION
Just show version and exit.
+version
Show version information for both the program and the Perl modules
that it uses, then exit.
Use --v option to show more details.
+libversion
Show version of openssl.
+quit
Show internal data and exit, used for debugging only.
Commands to check SSL details
Following (summary, internal) commands are simply a shortcut for
a list of other commands. For details of the list use:
   o-saft.pl --help=intern
+check
Check the SSL connection for security issues. This is the same as
+info +cipher +sizes --sslv2 --sslv3 --tlsv1 --tlsv11 --tlsv12
but also gives some kind of scoring for security issues if any.
+http
Perform HTTP checks (like STS, redirects etc.).
+info
Overview of most important details of the SSL connection.
Use --v option to show details also, which span multiple lines.
+info--v
Overview of all details of the SSL connection. This is a shortcut
for all commands listed below but not including +cipher.
This command is intended for debugging as it prints some details
from the used Net::SSLinfo module.
+quick
Quick overview of checks. Implies --enabled and --short.
+pfs
Check if servers offers ciphers with prefect forward secrecy (PFS)
+sts +hsts
Various checks according STS HTTP header.
This option implies --http, means that --no-http is ignored.
+sni
Check for Server Name Indication (SNI) usage.
+sni_check +check_sni
Check for Server Name Indication (SNI) usage and validity of all
names (CN, subjectAltName, FQDN, etc.).
+bsi
Various checks according BSI TR-02102-2 and TR-03116-4 compliance.
+ev
Various checks according certificate's extended Validation (EV).
Hint: use option --v --v to get information about failed checks.
+sizes
Check length, size and count of some values in the certificate.
+s_client
Dump data retrieved from openssl s_client ... call. Should be
used for debugging only.
It can be used just like openssl itself, for example:
        openssl s_client -connect host:443 -no_sslv2
+dump
Dumps internal data for SSL connection and target certificate.
This is mainly for debugging and should not be used together with
other commands (except +cipher).
Each key-value pair is enclosed in #{ and #} .
Using --trace --trace dumps data of Net::SSLinfo too.
+exec
Command used internally when requested to use other libraries.
This command should not be used directly.
Commands to test ciphers provided by target
+cipher
Check target for ciphers, either all ciphers or ciphers specified
with --cipher=* option.
Note that ciphers not supported by the local SSL implementation
are not checked by default, use +cipherall command for that.
+cipherall +cipherraw
Check target for all possible ciphers.
Does not depend on local SSL implementation.
In contrast to +cipher this command has some options to tweak
the cipher tests, connection results, and some strange behaviours
of the target. See #Options for +cipherall command for details.


+cipher-SSL
Get default cipher for protocol SSL.
Commands to test SSL connection to target
Please see:
   o-saft.pl --help=commands
Commands to show certificate details of the target
Please see:
   o-saft.pl --help=commands
Notes about commands
+extensions vs. +tlsextensions
+extensions shows the "Certificate extensions" and +tlsextensions
will show the TLS protocol extensions.
Use +tlsextdebug to show more informations about the TLS protocol
extensions.
+http2 +spdy +spdy3 +spdy31 +spdy4 +prots
These commands are just an alias for the +protocols command.

OPTIONS

All options are written in lowercase. Words written in all capital in
the description here is text provided by the user.
Options for help and documentation
--h
--help
WYSIWYG
--help=cmd
Show available commands.
--help=commands
Show available commands with short description.
--help=opt
Show available options; short form.
--help=options
Show available options with their description.
--help=checks
Show available checks.
--help=check-cfg --help=cfg-check
Show texts used as labels in output for checks (see +check) ready
for use in RC-FILE or as option.
--help=data
Show available informations.
--help=data-cfg --help=cfg-data
Show texts used as labels in output for data (see +info) ready
for use in RC-FILE or as option.
--help=hint
Show texts used in hint messages.
--help=hint-cfg --help=cfg-hint
Show texts used in hint messages ready for use in RC-FILE or as
option.
--help=text
Show texts used in various messages.
--help=text-cfg --help=cfg-text
Show texts used in various messages ready for use in RC-FILE or
as option.
--help=legacy
Show possible legacy formats (used as value in --legacy=KEY).
--help=compliance
Show available compliance checks.
--help=intern
Show internal commands.
--help=range
Show list of cipherranges (see --cipherrange=RANG).
--help=score
Show score value for each check.
Value is printed in format to be used for --cfg_score=KEY=SCORE.
Note that the sequence of options is important. Use the options
--trace and/or --cfg_score=KEY=SCORE before --help=score.
--help=toc --help=content
Show headlines from help textsUseful to get an overview.
--help=SECTION
Show <SECTION> from documentation, see --help=toc for a list.
Example:
     o-saft.pl --help=EXAMPLES
--help=regex
Show regular expressions used internally.
--help=gen-html
Show help text in HTML format.
--help=gen-wiki
Show help text in mediawiki format.
--help=gen-cgi
Generate HTML page with o-saft.cgi as form action..
--help=error --help=warning --help=problem
Show KNOWN PROBLEMS section with description of known error and
warning messages.
--help=FAQ
Show KNOWN PROBLEMS and LIMITATIONS section.
--help=glossar
Show common abbreviation used in the world of security.
--help=todo
Show known problems and bugs.
Options for all commands (general)
--no-rc
Do not read RC-FILE .
--dns
Do DNS lookups to map given hostname to IP, do a reverse lookup.
--no-dns
Do not make DNS lookups.
Note that the corresponding IP and reverse hostname may be missing
in some messages then.
--host=HOST
Specify HOST as target to be checked. Legacy option.
--port=PORT
Specify target's PORT to be used. Legacy option.
--host=HOST --port=PORT HOST:PORT HOST
When giving more than one HOST argument, the sequence of the given
HOST argument and the given --port=PORT and the given --host=HOST
options are important.
The rule how ports and hosts are mapped is as follows:
* HOST:PORT arguments are used as is (connection to HOST on PORT)
* only HOST is given, then previous specified --port=PORT is used
Note that URLs are treated as HOST:PORT, if they contain a port.
Example:
   o-saft.pl +cmd host-1 --port 23 host-2 host-3:42 host-4
will connect to:
      host-1:443
      host-2:23
      host-3:42
      host-4:23
--proxyhost=PROXYHOST --proxy=PROXYHOST:PROXYPORT
Make all connection to target using PROXYHOST.
Also possible is: --proxy=PROXYUSER:PROXYPASS@PROXYHOST:PROXYPORT
--proxyport=PROXYPORT
Make all connection to target using PROXYHOST:PROXYPORT.
--proxyuser=PROXYUSER
Specify username for proxy authentication.
--proxypass=PROXYPASS
Specify password for proxy authentication.
--proxy=PROXYUSER:PROXYPASS@PROXYHOST:PROXYPORT is also possible.
--starttls
Use STARTTLS command to start a TLS connection via SMTP.
This option is a shortcut for --starttls=SMTP
--starttls=PROT
Use STARTTLS command to start a TLS connection via protocol.
PROT may be any of: SMTP, IMAP, IMAP2, POP3, FTPS, LDAP, RDP, XMPP
For --starttls=SMTP see --dns-mx also to use MX records instead
of host
--starttls-delay=SEC
Number of seconds to wait before sending a packet, to slow down the
STARTTLS requests. Default is 0.
This may prevent blocking of requests by the target due to too much
or too fast connections.
Note: In this case there is an automatic suspension and retry with
a longer delay.
--cgi, --cgi-exec
Internal use for CGI mode only.
Options for SSL tool
--s_client
Use openssl s_slient ... call to retrieve more informations from
the SSL connection. This is disabled by default on Windows because
of performance problems. Without this option (default on Windows !)
following informations are missing on Windows:
      compression, expansion, renegotiation, resumption,
      selfsigned, verify, chain, protocols, DH parameters
See Net::SSLinfo for details.
If used together with --trace, s_client data will also be printed
in debug output of Net::SSLinfo.
--no-openssl
Do not use external openssl tool to retrieve informations. Use of
openssl is disabled by default on Windows.
Note that this results in some missing informations, see above.
--openssl=TOOL
TOOL can be a path to openssl executable; default: openssl
--openssl-cnf=FILE --openssl-conf=FILE
FILE path of directory or full path of openssl.cnf
If set, environment variable OPENSSL_CONF will be set to given path
(or file) when openssl(1) is started. Please see openssl's man page
for details about specifying alternate openssl.cnf files.
--force-openssl
Use openssl to check for supported ciphers; default: IO::Socket
This option forces to use openssl s_slient -connect CIPHER .. to
check if a cipher is supported by the remote target. This is useful
if the --lib=PATH option doesn't work (for example due to changes
of the API or other incompatibilities).
--exe-path=PATH --exe=PATH
PATH is a full path where to find openssl.
--lib-path=PATH --lib=PATH
PATH is a full path where to find libssl.so and libcrypto.so
See HACKER's INFO below for a detailed description how it works.
--envlibvar=NAME
NAME is the name of a environment variable containing additional
paths for searching dynamic shared libraries.
Default is LD_LIBRARY_PATH .
Check your system for the proper name, i.e.:
DYLD_LIBRARY_PATH, LIBPATH, RPATH, SHLIB_PATH .
--ssl-lazy
if the --lib=PATH option doesn't work (for example due to changes
I.g. this tools tries to identify available functionality according
SSL versions from the underlaying libraries. Unsupported versions
are then disables and a warning is shown.
Unfortunately some libraries have not implemented all functions to
check availability of a specific SSL version, which then results in
a compile error.
This option disables the strict check of availability.
If the underlaying library doesn't support the required SSL version
at all, following error may occour:
      Can't locate auto/Net/SSLeay/CTX_v2_new.al in @INC ...
-v
Print list of ciphers in style like: openssl ciphers -v.
Option used with +ciphers command only.
-V
Print list of ciphers in style like: openssl ciphers -V.
Option used with +ciphers command only.
Options for SSL connection to target
--cipher=CIPHER
  • CIPHER can be any string accepeted by openssl or following:
  • yeast use all ciphers from list defined herein, see +list
Beside the cipher names accepted by openssl, CIPHER can be the name
of the constant or the (hex) value as defined in openssl's files.
Currently supported are the names and constants of openssl 1.0.1k .
Example:
  • --cipher=DHE_DSS_WITH_RC4_128_SHA
  • --cipher=0x03000066
  • --cipher=66
will be mapped to DHE-DSS-RC4-SHA
Note: if more than one cipher matches, just one will be selected.
Default is ALL:NULL:eNULL:aNULL:LOW as specified in Net::SSLinfo
--ignore-no-connect
A simple check if the target can be connected will be performed by
default. If this check fails, the target will be ignored, means no
more reuqested checks will be done. As this connection check some-
times fails due to various reasons, the check can be disabled using
this option.
--no-md5-cipher
Do not use *-MD5 ciphers for other protocols than SSLv2.
This option is only effective with +cipher command.
The purpose is to avoid warnings from IO::Socket::SSL like:
        Use of uninitialized value in subroutine entry at lib/IO/Socket/SSL.pm line 430.
which occours with some versions of IO::Socket::SSL when a *-MD5
ciphers will be used with other protocols than SSLv2.
Note that these ciphers will be checked for SSLv2 only.
--SSL, -protocol SSL
--no-SSL
  • SSL can be any of:
ssl, ssl2, ssl3, sslv2, sslv3, tls1,
tls1, tls11, tls1.1, tls1-1, tlsv1, tlsv11, tlsv1.1, tlsv1-1
(and similar variants for tlsv1.2).
For example --tls1 --tlsv1 --tlsv1_1 are all the same.
(--SSL variants): Test ciphers for this SSL/TLS version.
(--no-SSL variants): Don't test ciphers for this SSL/TLS version.
--no-tcp
Shortcut for:
--no-sslv2 --no-sslv3 --no-tlsv1 --no-tlsv11 --no-tlsv12 --no-tlsv13
--tcp
Shortcut for: --sslv2 --sslv3 --tlsv1 --tlsv11 --tlsv12 --tlsv13
--no-udp
Shortcut for:
--no-dtlsv09 --no-dtlsv1 --no-dtlsv11 --no-dtlsv12 --no-dtlsv13
--udp
Shortcut for: --dtlsv09 --dtlsv1 --dtlsv11 --dtlsv12 --dtlsv13
--nullsslv2
This option forces to assume that SSLv2 is enabled even if the
target does not accept any ciphers.
The target server may accept connections with SSLv2 but not allow
any cipher. Some checks verify if SSLv2 is enabled at all, which
then would result in a failed test.
The default behaviour is to assume that SSLv2 is not enabled if no
ciphers are accepted.
--http
Make a HTTP request if cipher is supported.
If used twice debugging will be enabled using environment variable
HTTPS_DEBUG .
--no-http
Do not make HTTP request.
--sni
Make SSL connection in SNI mode.
--no-sni
Do not make SSL connection in SNI mode (default: SNI mode).
--sni-toggle --toggle-sni
Test with and witout SNI mode.
--force-sni
Do not check if SNI seems to be supported by Net::SSLeay(1).
Older versions of openssl and its libries do not support SNI or the
SNI support is implemented buggy. By default it's checked if SNI is
properly supported. With this option this check can be disabled.
Be warned that this may result in improper results.
--servername=NAME
--sni-name=NAME
Use NAME instead of given hostname to connect to target in SNI
mode. By default, NAME is automatically set to the given FQDN.
This is insufficient, when an IP instead of a FQDN was given, then
the connection needs to specify the correct hostname (i.g. a FQDN).
For historical reason, the value 1 is the same as if the the real
FQDN (given hostname) has been used. If the value is empty, or the
value 0 is given, no SNI name will be used.
Note: i.g. there is no need to use this option, as a correct value
for the SNI name will be choosen automatically (except for IPs).
However, it's kind of fuzzing ...
--no-cert
Do not get data from target's certificate, return empty string.
--no-cert --no-cert
Do not get data from target's certificate, return default string
of Net::SSLinfo (see --no-cert-text TEXT option).
--no-cert-text=TEXT
Set TEXT to be returned from Net::SSLinfo.pm if no certificate
data is collected due to use of --no-cert.
--ca-depth=INT
Check certificate chain to depth INT (like openssl's -verify).
--ca-file=FILE
Use FILE with bundle of CAs to verify target's certificate chain.
--ca-path=DIR
Use DIR where to find CA certificates in PEM format.
--no-nextprotoneg
Do not use -nextprotoneg option for openssl.
--no-reconnect
Do not use -reconnect option for openssl.
--no-tlsextdebug
Do not use -tlsextdebug option for openssl.
--sclient-opt=VALUE
Argument or option passed to openssl s_client command.
Options for +cipherall command
--range=RANGE
--cipherrange=RANGE
Specify range of cipher constants to be tested by +cipherall .
Following RANGEs are supported:
  • rfc all ciphers defined in various RFCs
  • shifted rfc, shifted by 64 bytes to the right
  • long like rfc but more lazy list of
  • huge all constants 0x03000000 .. 0x0300FFFF
  • safe all constants 0x03000000 .. 0x032FFFFF
  • full all constants 0x03000000 .. 0x0300FFFF
  • SSLv2 all ciphers according RFC for SSLv2
Note: SSLv2 is the internal list used for testing SSLv2 ciphers.
It does not make sense to use it for other protocols; however ...
--slow-server-delay=SEC
Additional delay in seconds after the server is connected using a
proxy or before starting STARTTLS.
This is useful when connecting via slow proxy chains or connecting
to slow servers before sending the STARTTLS sequence.
--ssl-maxciphers=CNT
Maximal number of ciphers sent in a sslhello (default: 32).
--ssl-double-reneg
Send SSL extension "reneg_info" even if list of ciphers includes
TLS_EMPTY_RENEGOTIATION_INFO_SCSV (default: do not include)
--ssl-nodata-nocipher
Do not abort testing for next cipher when the target responds with
"NoData" times out. Useful for TLS intolerant servers.
By default testing for ciphers is aborted when the target responds
with "noData message.
--ssl-use-ecc
Use supported elliptic curves. Default on.
--ssl-use-ec-point
Use TLS "ec_point_formats" extension. Default on.
--ssl-use-reneg
Test for ciphers with "secure renegotiation" flag set.
Default: don't set "secure renegotiation" flag.
--ssl-retry=CNT
Number of retries when connection timed-out (default: 2).
--ssl-timeout=SEC
Number of seconds to wait until connection is qualified as timeout.
--dns-mx, --mx
Get DNS MX records for given target and check the returned targets.
(only useful with --starttls=SMTP)
Options for checks and results
Options used for +check command:
--enabled
Only print result for ciphers accepted by target.
--disabled
Only print result for ciphers not accepted by target.
--ignorecase
Checks are done case insensitive.
--no-ignorecase
Checks are done case sensitive. Default: case insensitive.
Currently only checks according CN, alternate names in the target's
certificate compared to the given hostname are effected.
Options for output format
--short
Use short less descriptive text labels for +check and +info
command.
--legacy=TOOL
For compatibility with other tools, the output format used for the
result of the +cipher command can be adjusted to mimic the format
of other SSL testing tools.
The argument to the --legacy=TOOL option is the name of the tool
to be simulated.
Following TOOLs are supported:
  • sslaudit format of output similar to sslaudit
  • sslcipher format of output similar to ssl-cipher-check
  • ssldiagnos format of output similar to ssldiagnos
  • sslscan format of output similar to sslscan
  • ssltest format of output similar to ssltest
  • ssltestg format of output similar to ssltest -g
  • ssltest-g format of output similar to ssltest -g
  • sslyze format of output similar to sslyze
  • ssl-cipher-check same as sslcipher
  • ssl-cert-check format of output similar to ssl-cert-check
  • testsslserver format of output similar to TestSSLServer.jar
  • thcsslcHeck format of output similar to THCSSLCheck
Note that these legacy formats only apply to output of the checked
ciphers. Other texts like headers and footers are adapted slightly.
Please do not expect identical output as the TOOL when using these
options, it's a best guess and should be parsable in a very similar
way.
--legacy=compact
Internal format: mainly avoid tabs and spaces format is as follows:
Some Label:<-- anything right of colon is data
--legacy=full
Internal format: pretty print each label in its own line, followed
by data prepended by tab character (useful for +info only).
--legacy=quick
Internal format: use tab as separator; ciphers are printed with bit
length (implies --tab).
--legacy=simple
Internal default format.
--legacy=key
Internal format: print name of key instead of text as label. Key is
that of the internal data structure(s). For ciphers and protocols,
the corresponding hex value is used as key. Note that these values
are unique.
--format=FORM
  • raw Print raw data as passed from Net::SSLinfo .
Note: all data will be printed as is, without additional label
or formatting. It's recommended to use the option in conjunction
with exactly one command. Otherwise the user needs to know how
to "read" the printed data.
  • hex Convert some data to hex: 2 bytes separated by :.
  • 0x Convert some data with hex values:
2 bytes preceded by 0x and separated by a space.
  • /x Same as --format=\x
  • \x Convert some data with hex values:
2 bytes preceded by \x and no separating char.
--header
Print formatting header. Default for +check, +info, +quick.
and +cipher only.
--no-header
Do not print formatting header.
Usefull if raw output should be passed to other programs.
Note: must be used on command line to inhibit all header lines.
--ignore-cmd=CMD
--ignore-output=CMD
--no-cmd=CMD
--no-output=CMD
Do not print output (data or check result) for command CMD.
CMD is any valid command, see COMMANDS, without leading +.
Option can be used multiple times.
--score
Print scoring results. Default for +check.
--no-score
Do not print scoring results.
--separator=CHAR
--sep=CHAR
CHAR will be used as separator between label and value of the
printed results. Default is :
--tab
TAB character (0x09, \t) will be used as separator between label
and value of the printed results.
As label and value are already separated by a TAB character, this
options is only useful in conjunction with the --legacy=compact
option.
--showhost
Prefix each printed line with the given hostname (target).
The hostname will be followed by the separator character.
--win-CR
Print windows-Style with CR LF as end of line. Default is NL only.
Options for compatibility with other programs
Please see other programs for detailed description (if not obvious:).
Note that only the long form options are accepted as most short form
options are ambiguous.
Following list contains only those options not shown with:
 o-saft.pl --help=alias
Tool's Option        (Tool)          o-saft.pl Option
--------------------+---------------+---------------------------
 --checks CMD        (TLS-Check.pl)  same as +CMD
 -h, -h=HOST         (various tools) same as --host HOST
 -p, -p=PORT         (various tools) same as --port PORT
 -t HOST             (ssldiagnos)    same as --host HOST
 --protocol SSL      (ssldiagnos)    same as --SSL
 --UDP               (ssldiagnos)    same as --udp
 --insecure          (cnark.pl)      ignored
 --nopct --nocolor   (ssldiagnos)    ignored
 --timeout, --grep   (ssltest.pl)    ignored
 -r,  -s,  -t,  -x   (ssltest.pl)    ignored
 -connect, -H, -u, -url, -U          ignored
 -noSSL                              same as --no-SSL
 -no_SSL                             same as --no-SSL
--------------------+---------------+---------------------------
For definition of SSL see --SSL and --no-SSL above.
Options for customization
For general descriptions please see CUSTOMIZATION section below.
--cfg_cmd=CMD=LIST
Redefine list of commands. Sets  %cfg{cmd-CMD} to LIST. Commands
can be written without the leading +.
If CMD is any of the known internal commands, it will be redifned.
If CMD is a unknown command, it will be created.
Example: --cfg_cmd=sni=sni hostname
To get a list of commands and their settings, use:
   o-saft.pl --help=intern
Main purpose is to reduce list of commands or to print them sorted.
An example +preload can be found in .o-saft.pl .
--cfg_score=KEY=SCORE
Redefine value for scoring. Sets  %checks{KEY}{score} to SCORE.
Most score values are set to 10 by default. Values 0 .. 100 are
allowed.
To get a list of current score settings, use:
   o-saft.pl --help=score
For deatils how scoring works, please see SCORING section.
Use the --trace-key option for the +info and/or +check
command to get the values for KEY.
--cfg_checks=KEY=TEXT --cfg_data=KEY=TEXT
Redefine texts used for labels in output. Sets  %data{KEY}{txt} or
 %checks{KEY}{txt} to TEXT.
To get a list of preconfigured labels, use:
   o-saft.pl --help=cfg_checks
   o-saft.pl --help=cfg_data
--cfg_text=KEY=TEXT
Redefine general texts used in output. Sets  %text{KEY} to TEXT.
To get a list of preconfigured texts, use:
   o-saft.pl --help=cfg_text
Note that \n, \r and \t are replaced by the corresponding character
when read from RC-FILE.
--cfg_hint=KEY=TEXT
Redefine texts used for hints. Sets  %cfg{hints}{KEY} to TEXT.
To get a list of preconfigured texts, use:
   o-sat.pl --help=cfg-hint
--call=METHOD
See Options for SSL tool
--usr
Execute functions defined in o-saft-usr.pm.
--usr-*
--user-*
Options ignored, but stored as is internal in $cfg{usr-args} .
These options can be used in o-saft-usr.pm or o-saft-dbx.pm.
--experimental
Use experimental functionality.
Some functionality of this tool is under development and only used
when this option is given.
Options for tracing and debugging
--n
Do not execute, just show commands (only useful in conjunction with
using openssl).
Difference --trace vs. --v
While --v is used to print more data, --trace is used to print
more information about internal data such as procedure names and/or
variable names and program flow.
--v
--verbose
Print more information about checks.
Note that this option should be first otherwise some debug messages
are missing.
Note that --v is different from -v (see above).
--v --v
Print remotely checked ciphers.
--v --v --v
Print remotely checked ciphers one per line.
--v --v --v --v
Print processed ciphers (check, skip, etc.).
--trace
Print debugging messages.
--trace --trace
Print more debugging messages and pass trace=2 to Net::SSLeay and
Net::SSLinfo.
--trace --trace --trace
Print more debugging messages and pass trace=3 to Net::SSLeay and
Net::SSLinfo.
--trace --trace --trace --trace
Print processing of all command line arguments.
--trace--
--trace-arg
Print command line argument processing.
--trace-cmd
Trace execution of command processing (those given as +*).
--trace@
--trace-key
Print some internal variable names in output texts (labels).
Variable names are prefixed to printed line and enclosed in # .
Example without --trace-key :
      Certificate Serial Number:          deadbeef
Example with --trace-key :
      #serial#          Certificate Serial Number:          deadbeef
--trace=VALUE
Trace Option Alias Option
  • --trace=1 same as --trace
  • --trace=2 same as --trace --trace
  • --trace=arg same as --trace-arg
  • --trace=cmd same as --trace-cmd
  • --trace=key same as --trace-key
--trace-time
Prints timestamp in trace output (implies --trace-cmd).
--trace=FILE
Use FILE instead of the default rc-file (.o-saft.pl, see RC-FILE).
--trace-me
Print debugging messages for o-saft.pl only, but not any modules.
--trace-not-me
Print debugging messages for modules only, but not o-saft.pl istself.
--trace-sub +traceSUB
Print formatted list of internal functions with their description.
Not to be intended in conjunction with any target check.
--hint
Print hint messages (!!Hint:).
--no-hint
Do not print hint messages (!!Hint:).
--warning
Print warning messages (**WARNING:).
--no-warning
Do not print warning messages (**WARNING:).
--exit=KEY
For debugging only: terminate o-saft.pl at specified KEY.
For KEY please see: grep exit= o-saft.pl
Options vs. Commands
For compatibility with other programs and lazy users, some arguments
looking like options are silently taken as commands. This means that
--THIS becomes +THIS then. These options are:
  • --help
  • --abbr
  • --todo
  • --chain
  • --default
  • --fingerprint
  • --list
  • --version
Take care that this behaviour may be removed in future versions as it
conflicts with those options and commands which actually exist, like:
  • --sni vs. +sni

LAZY SYNOPSIS

Commands
Following strings are treated as a command instead of target names:
  • ciphers
  • s_client
  • version
A warning will be printed.
Options
We support following options, which are all identical, for lazy users
and for compatibility with other programs.
Option Variants
--port PORT
--port=PORT
This applies to most such options, --port is just an example.
When used in the RC-FILE, the --OPTION=VALUE variant must be used.
Option Names
Dash -, dot . and/or underscore _ in option names are optional,
all following are the same:
--no.dns
--no-dns
--no_dns
--nodns
This applies to all such options, --no-dns is just an example.
Targets
Following syntax is supported also:
   o-saft.pl http://some.tld other.tld:3889/some/path?a=b
Note that only the hostname and the port are used from an URL.
Options vs. Commands
See Options vs. Commands in OPTIONS section above

CHECKS

All SSL related check performed by the tool will be described here.
General Checks
Lookup the IP of the given hostname (FQDN), and then tries to reverse
resolve the FQDN again.
SSL Ciphers
Check which ciphers are supported by target. Please see RESULTS for
details of this check.
SSL Connection
heartbeat
Check if heartbead extension is supported by target.
poodle
Check if target is vulnerable to POODLE attack (SSLv3 enabled).
sloth
Check if target is vulnerable to SLOTH attack (server offeres RSA-MD5
or ECDSA-MD5 ciphers).
ALPN
Check if target supports ALPN. Following messages are evaluated:
   ALPN protocol: h2-14
   No ALPN negotiated
SSL Vulnerabilities
ADH
Check if ciphers for anonymous key exchange are supported: ADH|DHA .
Such key exchanges can be sniffed.
EDH
Check if ephemeral ciphers are supported: DHE|EDH .
They are necessary to support Perfect Forward Secrecy (PFS).
BEAST
Currently (2015) only a simple check is used: RC4 or CBC ciphers used.
Which is any cipher with RC4, ARC4 or ARCFOUR or with CBC.
TLSv1.2 checks are not yet implemented.
CRIME
Connection is vulnerable if target supports SSL-level compression.
DROWN
Connection is vulnerable if target supports SSLv2 (with at least one cipher).
FREAK
Attack Against SSL/TLS to downgrade to EXPORT ciphers.
Currently (2015) a simple check is used: SSLv3 enabled and EXPORT
ciphers supported by server.
See CVE-2015-0204 and https://freakattack.com/ .
HEARTBLEED
Check if target is vulnerable to heartbleed attack, see CVE-2014-0160
and http://heartbleed.com/ .
Logjam
Check if target is vulenerable to Logjam attack.
Check if target suports EXPORT ciphers and/or DH Parameter is less
than 2048 bits.
Lucky 13
Check if CBC ciphers are offered.
NOTE the recommendation to be safe againts Lucky 13 was to use RC4
ciphers. But they are also subjetc to attacks (see below). Hence the
check is only for CBC ciphers.
RC4
Check if RC4 ciphers are supported.
They are assumed to be broken.
Note that +rc4 reports the vulnerabilitiy to the RC4 Attack, while
+rc4_cipher simply reports if RC4 ciphers are offered. However the
the check, and hence the result, is the same.
PFS
Check if DHE ciphers are used. Also check if the TLS session ticket
is random or not used at all.
Currently (2015) only a simple check is used: only DHE ciphers used.
Which is any cipher with DHE or ECDHE. SSLv2 does not support PFS.
TLSv1.2 checks are not yet implemented.
POODLE
Check if target is vulnerable to POODLE attack (just check if SSLv3
is enabled).
Practical Invalid Curve Attack
This attack allows an attacker to read the servers private key if the
server does not check properly the passed points for a ecliptic curve
when EDH ciphers are used.
This check will not send multiple invalid points, but only checks if
the server closes the connection or responds with no matching cipher.
SLOTH
Currently (2016) we check for ciphers with ECDSA, RSA-MD5.
Checking the TLS extension 'tls-unique' is not yet implemented.
Target (server) Configuration and Support
BEAST, BREACH, CRIME, DROWN, FREAK, Logjam, Lucky 13, POODLE, RC4, SLOTH
See above.
Renegotiation
Check if the server allows client-side initiated renegotiation.
Version rollback attacks
NOT YET IMPLEMENTED
Check if the server allows changing the protocol.
DH Parameter
Check if target's DH Parameter is less 512 or 2048 bits.
Target (server) Certificate
Certificate Hashes
Check that fingerprint is not MD5.
Check that certificate private key signature is SHA2 or better.
Root CA
Provided certificate by target should not be a Root CA.
Self-signed Certificate
Certificate should not be self-signed.
IP in CommonName or subjectAltname (RFC6125)
NOT YET IMPLEMENTED
Basic Constraints
Certificate extension Basic Constraints should be CA:FALSE.
OCSP, CRL, CPS
Certificate should contain URL for OCSP and CRL.
Private Key encyption
Certificates signature key supports encryption.
Private Key encyption well known
Certificates signature key encryption algorithm is well known.
Public Key encyption
Certificates public key supports encryption.
Public Key encyption well known
Certificates public key encryption algorithm is well known.
Public Key Modulus size
Some (historic) SSL implementations are subject to buffer overflow if
the key exceeds 16384 or 32768 bits. The check is against 16384 bits.
Public Key Modulus Exponent size
The modulus exponent should be <= 65536 as some (mainly historic) SSL
implementations may have problems to connect.
Sizes and Lengths of Certificate Settings
Serial Number <= 20 octets (RFC5280, 4.1.2.2. Serial Number)
...
DV-SSL - Domain Validation Certificate
The Certificate must provide:
  • Common Name /CN= field
  • Common Name /CN= in subject or subjectAltname field
  • Domain name in commonName or altname field
EV-SSL - Extended Validation Certificate
This check is performed according the requirements defined by the CA/
Browser Forum https://www.cabforum.org/contents.html .
The Certificate must provide:
  • DV - Domain Validation Certificate (see above)
  • Organization name /O= Cn subject field
  • Organization name must be less to 64 characters
  • Business Category /businessCategory= in subject field
  • Registration Number /serialNumber= in subject field
  • Address of Place of Business in subject field
Required are: /C=, /ST=, /L=
Optional are: /street=, /postalCode=
  • Validation period does not exceed 27 month
See LIMITATIONS also.
Target (server) HTTP(S) Support
STS header (see RFC 6797)
Using STS is no perfect security. While the very first request using
http: is always prone to a MiTM attack, MiTM is possible to following
requests again, if STS is not well implemented on the server.
  • Request with http: should be redirected to https:
  • Redirects should use status code 301 (even others will work)
  • Redirect's Location header must contain schema https:
  • Redirect's Location header must redirect to same FQDN
  • Redirect may use Refresh instead of Location header (not RFC6797)
  • Redirects from HTTP must not contain STS header
  • Answer from redirected page (HTTPS) must contain STS header
  • Answer from redirected page for IP must not contain STS header
  • STS header must contain includeSubDirectoy directive
  • STS header max-age should be less than 1 month
  • STS must not be set in http-equiv attribute of a meta TAG
STS header preload attribute (+preload)
To satisfy the requirements on https://hstspreload.appspot.com/ the
HSTS header must:
  • have the max-age with at least 18 weeks (10886400 seconds)
  • have the includeSubDomains attribute
  • have the preload attribute
  • redirect to https first, then to sub-domains (if redirected)
  • have an HSTS header in each redirect to https.
Additionally, the site must have:
  • a valid certificate
  • serve all subdomains over https.
Except the last requirement, +preload will do the checks.
Note that +preload is defined in .o-saft.pl only.
Publix Key Pins header
TBD - to be described ...
Compliances
Note that it is not possible to satisfy all following compliances. Best
match is: PSF and ISM and PCI and lazy BSI TR-02102-2.
In general it is difficult to satisfy all conditions of a compliances,
and it is also difficult to check all these conditions. That's why some
of the compliances checks are not completely implemented, for details
please see blow.
Note that output of results of some checks is disabled in the RC-FILE
by default. A "**Hint:" message will be printed, if any of these checks
are used.
BSI TR-02102-2 (+bsi-tr-02102+ +bsi-tr-02102- +bsi)
Checks if connection and ciphers are compliant according TR-02102-2,
see https://www.bsi.bund.de/SharedDocs/Downloads/DE/BSI/Publikationen
/TechnischeRichtlinien/TR02102/BSI-TR-02102-2_pdf.pdf?__blob=publicationFile
(following headlines are taken from there)
  • 3.2.1 Empfohlene Cipher Suites
  • 3.2.2 Übergangsregelungen
RC4 allowed temporary for TLS 1.0. Only if TLS 1.1 and TLS 1.2
cannot be supported.
  • 3.2.3 Mindestanforderungen für Interoperabilität
Must at least support: ECDHE-ECDSA-* and ECDHE-RSA-*
  • 3.3 Session Renegotation
Only server-side (secure) renegotiation allowed (see RFC5280).
  • 3.4 Zertifikate und Zertifikatsverifikation
Must have CRLDistributionPoint or AuthorityInfoAccess.
MUST have OCSP URL.
PrivateKeyUsage must not exceed three years for certificate and
must not exceed five years for CA certificates.
Subject, CommonName and SubjectAltName must not contain
a wildcard.
Certificate itself must be valid according dates if validity.
Note that the validity check relies on the years provided by the
certificate's before and after values only. For example a
certificate valid from Jan 2013 to Mar 2016 is considered valid
even the validity is more than three years.
All certificates in the chain must be valid.
**NOT YET IMPLEMENTED**
Above conditions are not required for lazy checks.
  • 3.5 Domainparameter und Schlüssellängen
**NOT YET IMPLEMENTED**
  • 3.6 Schlüsselspeicherung
This requirement is not testable from remote.
  • 3.7 Umgang mit Ephemeralschlüsseln
This requirement is not testable from remote.
  • 3.8 Zufallszahlen
This requirement is not testable from remote.
BSI TR-03116-4 (+bsi-tr-03116+ +bsi-tr-03116- +bsi)
Checks if connection and ciphers are compliant according TR-03116-4,
see https://www.bsi.bund.de/SharedDocs/Downloads/DE/BSI/Publikationen
/TechnischeRichtlinien/TR03116/BSI-TR-03116-4.pdf?__blob=publicationFile
(following headlines are taken from there)
  • 2.1.1 TLS-Versionen und Sessions
Allows only TLS 1.2.
  • 2.1.2 Cipher Suites
Cipher suites must be ECDHE-ECDSA or -RSA with AES128 and SHA265.
For curiosity, stronger cipher suites with AES256 and/or SHA384 are
not not allowed. To follow this curiosity the +bsi-tr-03116- (lazy)
check allows the stronger cipher suites ;-)
  • 2.1.1 TLS-Versionen und Sessions
The TLS session lifetime must not exceed 2 days.
  • 2.1.4.2 Encrypt-then-MAC-Extension
  • 2.1.4.3 OCSP-Stapling
MUST have OCSP Stapling URL.
  • 4.1.1 Zertifizierungsstellen/Vertrauensanker
Certificate must provide all root CAs. (NOT YET IMPLEMENTED).
Should use a small certificate trust chain.
  • 4.1.2 Zertifikate
Must have CRLDistributionPoint or AuthorityInfoAccess.
End-user certificate must not be valid longer than 3 years.
Root-CA certificate must not be valid longer than 5 years.
Certificate extension pathLenConstraint must exist, and should be
a small value ("small" is not defined).
All certificates must contain the extension KeyUsage.
Wildcards for CN or Subject or SubjectAltName are not allowed
in any certificate.
EV certificates are recommended (NOT YET checked properly).
  • 4.1.3 Zertifikatsverifikation
Must verify all certificates in the chain down to their root-CA.
(NOT YET IMPLEMENTED).
Certificate must be valid according issue and expire date.
All Checks must be doen for all certificates in the chain.
  • 4.1.4 Domainparameter und Schlüssellängen
This requirement is not testable from remote.
  • 4 5.2 Zufallszahlen
This requirement is not testable from remote.
RFC 6125 (+rfc6125)
Checks values CommonName, Subject and SubjectAltname of the
certificate for:
  • must all be valid characters for DNS
  • must not contain more than one wildcards
  • must not contain invalid wildcards
  • must not contain invalid IDN characters
RFC 6797 (+rfc6797)
Same as STS header +hsts .
RFC 7525 (+rfc7525)
Checks if connection and ciphers are compliant according RFC 7525.
See http://tools.ietf.org/rfc/rfc7525.txt
(following headlines are taken from there)
  • 3.1.1. SSL/TLS Protocol Versions
SSLv2 and SSLv3 must not be supportetd.
TLSv1 should only be supported if there is no TLSv1.1 or TLSv1.2.
Either TLSv1.1 or TLSv1.2 must be supported, prefered is TLSv1.2.
  • 3.1.2. DTLS Protocol Versions
DTLSv1 and DTLSv1.1 must not be supported.
  • 3.1.3. Fallback to Lower Versions
(check implecitely done by 3.1.1, see above)
  • 3.2. Strict TLS
Check if server provides Strict Transport Security.
(STARTTLS check NOT YET IMPLEMENTED).
  • 3.3. Compression
Compression on TLS must not be supported.
  • 3.4. TLS Session Resumption
Server must support resumtion and random session tickets.
(Randomnes of session tickets implemented YET experimental.)
Check if ticket is authenticated and encrypted NOT YET IMPLEMENTED.
  • 3.5. TLS Renegotiation
Server must support renegotiation.
  • 3.6. Server Name Indication
(Check for SNI support implemented experimental.)
  • 4. Recommendations: Cipher Suites
  • 4.1. General Guidelines
  • 4.2. Recommended Cipher Suites
Check for recommended ciphers.
  • 4.3. Public Key Length
DH parameter must be at least 256 bits or 2048 its with EC.
(Check currently, 4/2016, based on openssl which may not provide DH
parameters for all ciphers.)
  • 4.5. Truncated HMAC
TLS extension "truncated hmac" must not be used.
  • 6. Security Considerations
  • 6.1. Host Name Validation
Given hostname must matches hostname in certificate's subject.
  • 6.2. AES-GCM
  • 6.3. Forward Secrecy
  • 6.4. Diffie-Hellman Exponent Reuse
(NOT YET IMPLEMENTED).
  • 6.5. Certificate Revocation
OCSP and CRL Distrbution Point in cetificate must be defined.

OUTPUT

All output is designed to make it easily parsable by postprocessors.
Following rules are used:
  • Lines for formatting or header lines start with =.
  • Lines for verbosity or tracing start with #.
  • Errors and warnings start with **.
  • Empty lines are comments ;-)
  • Label texts end with a separation character; default is :.
  • Label and value for all checks are separated by at least one TAB :character.
  • Texts for additional information are enclosed in << and >>.
  • N/A is used when no proper informations was found or provided.
Replace N/A by whatever you think is adequate: "No answer",
"Not available", "Not applicable", ...
When used in --legacy=full or --legacy=simple mode, the output
may contain formatting lines for better (human) readability.
Postprocessing Output
It is recommended to use the --legacy=quick option, if the output
should be postprocessed, as it omits the default separation character
(: , see above) and just uses on single tab character (0x09, \t or
TAB) to separate the label text from the text of the result. Example:
        Label of the performed checkTABresult
More examples for postprocessing the output can be found here:
https://github.com/OWASP/O-Saft/blob/master/contrib

CUSTOMIZATION

This tools can be customized as follows:
  • Using command line options
This is a simple way to redefine specific settings. Please see
CONFIGURATION OPTIONS below.
  • Using Configuration file
A configuration file can contain multiple configuration settings.
Syntax is simply KEY=VALUE. Please see CONFIGURATION FILE below.
  • Using resource files
A resource file can contain multiple command line options. Syntax
is the same as for command line options iteself. Each directory
may contain its own resource file. Please see RC-FILE below.
  • Using debugging files
These files are --nomen est omen-- used for debugging purposes.
However, they can be (mis-)used to redefine all settings too.
Please see DEBUG-FILE below.
  • Using user specified code
This file contains user specified program code. It can also be
(mis-)used to redefine all settings. Please see USER-FILE below.
Customization is done by redefining values in internal data structure
which are:  %cfg,  %data,  %checks,  %text,  %scores .
Unless used in DEBUG-FILE or USER-FILE, there is no need to know
these internal data structures or the names of variables; the options
will set the proper values. The key names being part of the option,
are printed in output with the --trace-key option.
I.g. texts (values) of keys in  %data are those used in output of the
Informations section. Texts of keys in  %checks are used for output
in Performed Checks section. And texts of keys in  %text are used
for additional information lines or texts (mainly beginning with =).
Configuration File vs. RC-FILE vs. DEBUG-FILE
  • CONFIGURATION FILE
Configuration Files must be specified with one of the --cfg_*
options. The specified file can be a valid path. Please note that
only the characters: a-zA-Z_0-9,.\/()- are allowed as pathname.
Syntax in configuration file is: KEY=VALUE where KEY is any
key as used in internal data structure.
the keys in output).
  • RC-FILE
Resource files are searched for and used automatically.
For details see RC-FILE below.
  • DEBUG-FILE
Debug files are searched for and used automatically.
For details see DEBUG-FILE below.
  • USER-FILE
The user program file is included only if the --usr option was
used. For details see USER-FILE below.
CONFIGURATION OPTIONS
Configuration options are used to redefine texts and labels or score
settings used in output. The options are:
  • --cfg-cmd=KEY=LIST
  • --cfg-checks=KEY=TEXT
  • --cfg-data=KEY=TEXT
  • --cfg-hint=KEY=TEXT
  • --cfg-text=KEY=TEXT
Here KEY is the key used in the internal data structure and TEXT
is the value to be set for this key. Note that unknown keys will be
ignored silently.
If KEY=TEXT is an exiting filename, all lines from that file are
read and set. For details see CONFIGURATION FILE below.
NOTE that such configuration options should be used before any --help
or --help=* option, otherwise the changed setting is not visible.
CONFIGURATION FILE
Note that the file can contain KEY=TEXT pairs for any kind of the
configuration as given by the --cfg_CFG option.
For example when used with --cfg_text=file only values for  %text
will be set, when used with --cfg_data=file only values for %data
will be set, and so on. KEY is not used when KEY=TEXT is an existing
filename. Though, it's recommended to use a non-existing key, i.e.:
--cfg-text=my_file=some/path/to/private/file .
RC-FILE
The rc-file will be searched for in the working directory only.
The name of the rc-file is the name of the program file prefixed by a
. (dot), for example: .o-saft.pl.
A rc-file can contain any of the commands and options valid for the
tool itself. The syntax for them is the same as on command line. Each
command or option must be in a single line. Any empty or comment line
will be ignored. Comment lines start with # or =.
Note that options with arguments must be used as KEY=VALUE instead
of KEY VALUE.
Configurations options must be written like --cfg-CFG=KEY=VALUE
where "CFG" is any of: cmd, check, data, text or score and "KEY is
any key from internal data structure (see above).
All commands and options given on command line will overwrite those
found in the rc-file.
DEBUG-FILE
All debugging functionality is defined in o-saft-dbx.pm, which will
be searched for using paths available in perl's @INC variable.
Syntax in this file is perl code. For details see DEBUG below.
USER-FILE
All user functionality is defined in o-saft-usr.pm, which will be
searched for using paths available in perl's @INC variable.
Syntax in this file is perl code.
All functions defined in o-saft-usr.pm are called when the option
--usr was given. The functions are defined as empty stub, any code
can be inserted as need. Please see perldoc o-saft-usr.pm to see
when and how these functions are called.
SHELL TWEAKS
Configuring the shell environment where the tool is startet, must be
done before the tools starts. It is not really a task for the tool
itself, but it can simplify your life, somehow.
There exist customizations for some commonly used shells, please see
the files in the ./contrib/ directory.
COMMANDS
The option --cfg-cmd=CMD=LIST can be used to define own commands.
When configuring own commands, CMD must not be one of the commands
listed with --help=intern and CMD must constist only of digits and
letters.

CIPHER NAMES

While the SSL/TLS protocol uses integer numbers to identify ciphers,
almost all tools use some kind of `human readable' texts for cipher
names.
These numbers (which are most likely written as hex values in source
code and documentations) are the only true identifier, and we have to
rely on the tools that they use the proper integers.
As such integer or hex numbers are difficult to handle by humans, we
decided to use human readable texts. Unfortunately no common standard
exists how to construct the names and map them to the correct number.
Some, but by far not all, oddities are described in Name Rodeo.
The rules for specifying cipher names are:
  • 1. textual names as defined by IANA (see [IANA])
  • 2. mapping of names and numbers as defined by IANA (see [IANA])
  • 3. - and _ are treated the same
  • 4. abbreviations are allowed, as long as they are unique
  • 5. beside IANA, openssl's cipher names are preferred
  • 6. name variants are supported, as long as they are unique
  • 7. hex numbers can be used
[IANA] http://www.iana.org/assignments/tls-parameters/tls-parameters.txt September 2013
[openssl] ... openssl 1.0.1
If in any doubt, use +list to get an idea about the mapping.
Use --help=regex to see which regex are used to handle all these
variants herein.
Mind the traps and dragons with cipher names and what number they are
actually mapped to. In particular when --lib, --exe or --openssl
options are in use. Always use these options with +list command too.
Name Rodeo
As said above, the SSL/TLS protocol uses integer numbers to identify
ciphers, but almost all tools use some kind of human readable texts
for cipher names.
For example the cipher commonly known as DES-CBC3-SHA is identified
by 0x020701c0 (in openssl) and has SSL2_DES_192_EDE3_CBC_WITH_SHA
as constant name. A definition is missing in IANA, but there is
TLS_RSA_WITH_3DES_EDE_CBC_SHA .
It's the responsibility of each tool to map the human readable cipher
name to the correct (hex, integer) identifier.
For example Firefox uses dhe_dss_des_ede3_sha, which is what?
Furthermore, there are different acronyms for the same thing in use.
For example DHE and EDH both mean "Ephemeral Diffie-Hellman".
Comments in the openssl(1) sources mention this. And for curiosity
these sources use both in cypher names but allow EDH as shortcut
only in openssl's "ciphers" command. Wonder about (up to 1.0.1h):
   openssl ciphers -V EDH
   openssl ciphers -V DHE
   openssl ciphers -V EECDH
   openssl ciphers -V ECDHE
Next example is ADH which is also known as DH_anon or DHAnon
or DHA or ANON_DH.
You think this is enough? Then have a look how many acronyms are used
for "Tripple DES".
Compared to above, the interchangeable use of - vs. _ in human
readable cipher names is just a very simple one. However, see openssl
again what following means (returns):
   openssl ciphers -v RC4-MD5
   openssl ciphers -v RC4+MD5
   openssl ciphers -v RC4:-MD5
   openssl ciphers -v RC4:!MD5
   openssl ciphers -v RC4!MD5
Looking at all these oddities, it would be nice to have a common unique
naming scheme for cipher names. We have not. As the SSL/TLS protocol
just uses a number, it would be natural to use the number as uniq key
for all cipher names, at least as key in our internal sources.
Unfortunately, the assignment of ciphers to numbers changed over the
years, which means that the same number refers to a different cipher
depending on the standard, and/or tool, or version of a tool you use.
As a result, we cannot use human readable cipher names as identifier
(aka unique key), as there are to many aliases for the same cipher.
And also the number cannot be used as unique key, as a key may have
multiple ciphers assigned.

KNOWN PROBLEMS

This section describes knwon problems, and known error messages which
may occour when using o-saft.pl. This sections can be used as FAQ too
as it gives hints and workarounds.
Segmentation fault
Sometimes the program terminates with a Segmentation fault. This
mainly happens if the target does not return certificate information.
If so, the --no-cert option may help.
**WARNING: empty result from openssl; ignored at ...
This most likely occurs when the provided cipher is not accepted by
the server, or the server expects client certificates.
**WARNING: unknown result from openssl; ignored at ...
This most likely occurs when the openssl executable is used with a
very slow connection. Typically the reason is a connection timeout.
Try to use --timeout=SEC option.
To get more information, use --v --v and/or --trace also.
**WARNING: undefined cipher description
May occour if ciphers are checked, but no description is available for
them herein. This results in printed cipher checks like:
        EXP-KRB5-RC4-MD5                no       <undef>>
instead of:
        EXP-KRB5-RC4-MD5                no       weak
**WARNING: Can't make a connection to your.tld:443; no initial data
**WARNING: Can't make a connection to your.tld:443; target ignored
This message occours if the underlaying SSL library (i.e. libssl.a)
was not able to connect to the target. Known observed reasons are:
  • target does not support SSL protocol on specified port
  • target expects a client certificate in ClientHello message
More details why the connection failed can be seen using --trace=2 .
If the targets supports SSL, it should be at least possible to check
for supported ciphers using +cipherall instead of +cipher .
Use of uninitialized value $headers in split ... do_httpx2.al)
The warning message (like follows or similar):
Use of uninitialized value $headers in split at blib/lib/Net/SSLeay.pm
(autosplit into blib/lib/auto/Net/SSLeay/do_httpx2.al) line 1290.
occurs if the target refused a connection on port 80.
This is considered a bug in Net::SSLeay.
Workaround to get rid of this message: use --no-http option.
invalid SSL_version specified at ... IO/Socket/SSL.pm
This error may occur on systems where a specific SSL version is not
supported. Subject are mainly SSLv2, SSLv3 TLSv1.3 and DTLSv1.
For DTLSv1 the full message looks like:
      invalid SSL_version specified at C:/programs/perl/perl/vendor/lib/IO/Socket/SSL.
See also Note on SSL versions .
Workaround: use options like: --no-sslv2 --no-sslv3 --no-tlsv13 --no-dtlsv1
Use of uninitialized value $_[0] in length at (eval 4) line 1.
This warning occours with IO::Socket::SSL 1.967, reason is unknown.
It seems not to harm functionality, hence no workaround, just ignore.
Use of uninitialized value in subroutine entry at lib/IO/Socket/SSL.pm line 430.
Some versions of IO::Socket::SSL return this error message if *-MD5
ciphers are used with other protocols than SSLv2.
Workaround: use --no-md5-cipher option.
Can't locate auto/Net/SSLeay/CTX_v2_new.al in @INC ...
Underlaying library doesn't support the required SSL version.
See also Note on SSL versions .
Workaround: use --ssl-lazy option, or corresponding --no-SSL option.
Read error: Connection reset by peer (,199725) at blib/lib/Net/SSLeay.pm (autosplit into blib/lib/auto/Net/SSLeay/tcp_read_all.al) line 535.
Error reported by some Net::SSLeay versions. Reason may be a timeout.
This error cannot be omitted or handled properly.
Workaround: try to use same call again (no guarantee, unfortunatelly)
openssl: ...some/path.../libssl.so.1.0.0: no version information available (required by openssl)
Mismatch of openssl executable and loaded underlaying library. This
most likely happens when options --lib=PATH and/or --exe=PATH are
used. See also Note on SSL versions .
Hint: use following commands to get information about used libraries:
  o-saft.pl +version
  o-saft.pl --v --v +version
Integer overflow in hexadecimal number at ...
This error message may occour on 32-bit systems if perl was not com-
piled with proper options. I.g. perl automatically converts the value
to a floating pont number.
Please report a bug with output of following command:
  o-saft.pl +s_client +dump your.tld
<<openssl did not return DH Paramter>>
Text may be part of a value. This means that all checks according DH
parameters and logkam attack cannot be done.
Workaround: try to use --openssl=TOOL option.
This text may appears in any of the compliance checks (like +rfc7525)
which may be a false positive. For these checks openssl is also used
to get the DH Parameter.
Workaround: not available yet
No output with +help and/or --help=todo
On some (mainly Windows-based) systems using
  o-saft.pl +help
  o-saft.pl --help
does not print anything.
Workaround: use --v option.
  o-saft.pl +help --v
or
  o-saft.pl +help | more
**WARNING: on MSWin32 additional option --v required, sometimes ...
On some (mainly Windows-based) systems this may happen when calling
for example:
  o-saft.pl --help=FAQ
which then may produce:
  **WARNING: on MSWin32 additional option  --v  required, sometimes ...
  === reading: ./.o-saft.pl (RC-FILE done) ===
  === reading: Net/SSLinfo.pm (O-Saft module done) ===
  **USAGE: no command given
  # most common usage: 
    o-saft.pl +info   your.tld
    o-saft.pl +check  your.tld
    o-saft.pl +cipher your.tld
  # for more help use:
    o-saft.pl --help 
Workaround: use full path to perl.exe, for example
  C:\Programs\perl\bin\perl.exe o-saft.pl --help=FAQ
Performance Problems
There are various reasons when the program responds slow, or seems to
hang. Beside the problems described below performance issues are most
likely a target-side problem. Most common reasons are:
  • a) DNS resolver problems
Try with --no-dns
  • b) target does not accept connections for https
Try with --no-http
  • c) target's certificate is not valid
Try with --no-cert
  • d) target expects that the client provides a client certificate
No option provided yet ...
  • e) target does not handle Server Name Indication (SNI)
Try with --no-sni
  • f) use of external openssl(1) executable
Use --no-openssl
Other options which may help to get closer to the problem's cause:
--timeout=SEC, --trace, --trace=cmd

LIMITATIONS

Commands
Some commands cannot be used together with others, for example:
+cipher, +ciphers, +list, +libversion, +version, +check, +help,
+protocols .
+quick should not be used together with other commands, it returns
strange output then.
+protocols requires openssl(1) with support for -nextprotoneg
option. Otherwise the value will be empty.
Options
The option --port=PORT must preceed --host=HOST for a target like
HOST:PORT .
The characters + and = cannot be used for --separator option.
Following strings should not be used in any value for options:
+check, +info, +quick, --header
as they my trigger the ---header option unintentional.
The used timeout(1) command cannot be defined with a full path like
openssl(1) can with the --openssl=path/to/openssl.
--cfg_text=file cannot be used to redefine the texts yes and no
as used in the output for +cipher command.
Checks (general)
+constraints
This check is only done for the certificate provided by the target.
All other certificate in the chain are not checked.
This is currently (2015) a limitation in o-saft.pl.
Broken pipe
This error message most likely means that the connection to specified
target was not possible (firewall or whatever reason).
Target Certificate Chain Verification
The systems default capabilities i.e. libssl.so, openssl, are used to
verify the target's certificate chain. Unfortunately various systems
have implemented different approaches and rules how identify and how
to report a successful verification. As a consequence this tool can
only return the same information about the chain verification as the
used underlying tools. If that information is trustworthy depends on
how trustworthy the tools are.
These limitations apply to following commands:
  • +verify
  • +selfsigned
Following commands and options are useful to get more information:
  • +chain_verify, +verify, +error_verify, +chain, +s_client
  • --ca-file, --ca-path, --ca-depth
User Provided Files
Please note that there cannot be any guarantee that the code provided
in the DEBUG-FILE o-saft-usr.pm or USER-FILE o-saft-usr.pm
will work flawless. Obviously this is the user's responsibility.
Problems and Errors
Checking the target for supported ciphers may return that a cipher is
not supported by the server misleadingly. Reason is most likely an
improper timeout for the connection. See --timeout=SEC option.
If the specified targets accepts connections but does not speak SSL,
the connection will be closed after the system's TCP/IP-timeout. This
script will hang (about 2-3 minutes).
If reverse DNS lookup fails, an error message is returned as hostname,
like: <<gethostbyaddr() failed>>.
Workaround to get rid of this message: use --no-dns option.
All checks for EV are solely based on the information provided by the
certificate.
Some versions of openssl (< 1.x) may not support all required options
which results in various error messages or --more worse-- may not be
visibale at all.
Following table shows the openssl option and how to disbale it within
o-saft:
-nextprotoneg --no-nextprotoneg
-reconnect --no-reconnect
-tlsextdebug --no-tlsextdebug
Poor Systems
Use of openssl(1) is disabled by default on Windows due to various
performance problems. It needs to be enabled with --openssl option.
On Windows the usage of openssl s_client needs to be enabled using
--s_client option.
On Windows it's a pain to specify the path for --openssl=.. option.
Variants are:
  • --openssl=/path/to/openssl.exe
  • --openssl=X:/path/to/openssl.exe
  • --openssl=\path\to\openssl.exe
  • --openssl=X:\path\to\openssl.exe
  • --openssl=\\path\\to\\openssl.exe
  • --openssl=X:\\path\\to\\openssl.exe
You have to fiddle around to find the proper one.
Debug and Trace Output
When both --trace=key and --trace=cmd options are used, output is
mixed, obviously. Hint: output for --trace=cmd always contains "CMD".

DEPENDENCIES

All perl modules and all private moduels and files will be searched
for using paths available in perl's @INC variable. @INC will
be prepended by following paths:
  • .
  • ./lib
  • INSTALL_PATH
  • INSTALL_PATH/lib
Where INSTALL_PATH is the path where the tool is installed.
To see which files have been included use:
   o-saft.pl +version --v --user
Perl Modules
  • IO::Socket::SSL(1)
  • IO::Socket::INET(1)
  • Net::SSLeay(1)
  • Net::SSLinfo(1)
  • Net::SSLhello(1)
Additional Files used if requested
  • .o-saft.pl
  • o-saft-dbx.pm
  • o-saft-man.pm
  • o-saft-usr.pm
  • o-saft-README

INSTALLATION

The tool can be installed in any path. It just requres the modules as
described in DEPENDENCIES above. However, it's recommended that the
modules Net::SSLhello and Net::SSLinfo are found in the directory
./Net/ where o-saft.pl is installed.
For security reasons, most modern libraries disabled or even removed
insecure or "dirty" functionality. As this tool's purpose is to find
such insecure settings, functions, etc., it needs these dirty things
enabled. What we need is (incomplete list):
  • insecure protocols like SSLv2, SSLv3
  • more more ciphers enabled, like NULL-MD5, AECDH-NULL-SHA, etc.
  • some SSL extensions and options
Therefore we recommend to compile and install at least following:
  • openssl with SSLv2, SSLv3 and more ciphers enabled
  • Net::SSLeay compiled with openssl version as described before.
Please read the SECURITY section first before following the install
instructions below.
OpenSSL
Currently it is recommend to use either the openssl version from
https://github.com/PeterMosmans/openssl/ which requires compilation,
see Example: Compile OpenSSL, or use any of the precomiled versions
which are available for several platforms at https://testssl.sh/ .
The sources are available at
The precomiled static versions are available at
For all following installation examples we assume:
  • openssl-1.0.2-chacha.zip or openssl-1.0.2d.tar.gz
  • /usr/local as bae installation directory
  • a bourne shell (sh) compatible shell
Example: Precompiled OpenSSL
Simply download the tarball or zip file for your platform, unpack it,
and install (copy) the binaries into a directory of your choice.
Example: Compile OpenSSL
OpenSSL can be used from http://openssl.org/ or, as recommended, from
https://github.com/PeterMosmans/openssl/ .
OpenSSL-chacha
Compiling and installing the later is as simple as:
   unzip openssl-1.0.2-chacha.zip
   cd openssl-1.0.2-chacha
   ./config --shared -Wl,-rpath=/usr/local/lib
   make
   make test
   make install
which will install openssl, libssl.so, libcrypto.so and some include
files as well as the include files in /usr/local/ .
The shared version of the libraries are necessary for Net::SSLeay.
OpenSSL.org
Building openssl from the offical openssl.org sources requires some
patching before compiling and installing the libraries and binaries.
Example with openssl-1.0.2d:
  echo == unpack tarball
  tar xf openssl-1.0.2d.tar.gz
  cd openssl-1.0.2d

  echo == backup files to be modified
  cp ssl/s2_lib.c{,.bak}
  cp ssl/s3_lib.c{,.bak}
  cp ssl/ssl3.h{,.bak}
  cp ssl/tls1.h{,.bak}
  echo == patch files
  vi ssl/tls1.h         +/TLS1_ALLOW_EXPERIMENTAL_CIPHERSUITES/
           # define TLS1_ALLOW_EXPERIMENTAL_CIPHERSUITES  1
  vi ssl/ssl3.h ssl/s{2,3}_lib.c   +"/# *if 0/"
           #==> remove all   # if 0  and corresponding  #endif
           #    except if lines contain:
           #        _FZA
           #        /* Fortezza ciphersuite from SSL 3.0
           #        /* Do not set the compare functions,
           #        if (s->shutdown & SSL_SEND_SHUTDOWN)
  echo == configure with static libraries
  echo omitt the zlib options if zlib-1g-dev is not installed
  echo omitt the krb5 options if no kerberos libraries available
  ./config --prefix=/usr/local --openssldir=/usr/local/ssl \
      enable-zlib zlib zlib-dynamic enable-ssl2 \
      enable-krb5 --with-krb5-flavor=MIT \
      enable-mdc2 enable-md2  enable-rc5  enable-rc2 \
      enable-cms  enable-ec   enable-ec2m enable-ecdh enable-ecdsa \
      enable-gost enable-seed enable-idea enable-camellia \
      enable-rfc3779 enable-ec_nistp_64_gcc_128 \
      experimental-jpake -fPIC \
      -DTEMP_GOST_TLS -DTLS1_ALLOW_EXPERIMENTAL_CIPHERSUITES \
      shared
  echo == make binaries and libraries
  make depend
  make
  make test
  make install
  echo == if you want static binaries and libraries
  make clean
  echo same ./config as before but without shared option
  ./config --prefix=/usr/local --openssldir=/usr/local/ssl \
      enable-zlib zlib zlib-dynamic enable-ssl2 \
      enable-krb5 --with-krb5-flavor=MIT \
      enable-mdc2 enable-md2 enable-rc5 enable-rc2 \
      enable-cms  enable-ec   enable-ec2m enable-ecdh enable-ecdsa \
      enable-gost enable-seed enable-idea enable-camellia \
      enable-rfc3779 enable-ec_nistp_64_gcc_128 \
      experimental-jpake -fPIC \
      -DTEMP_GOST_TLS -DTLS1_ALLOW_EXPERIMENTAL_CIPHERSUITES
  make depend
  make
  make test
  echo next make will overwrite the previously installed dynamic
  echo shared openssl binary with the static openssl binary
  make install
Example: Compile Net::SSLeay
To enable support for ancient protocol versions, Net::SSLeay must be
compiled manually after patching 'SSLeay.xs' (see below).
Reason is, that Net::SSLeay enables some functionality for SSL/TLS
according the identified openssl version. There is, currently (2015),
no possibility to enable this functionality by passing options on to
the configuration script perl Makefile.PL.
   echo == unpack tarball
   tar xf Net-SSLeay-1.72.tar.gz
   cd Net-SSLeay-1.72
   echo == patch files
   echo "edit SSLeay.xs and change some #if as described below"
   env OPENSSL_PREFIX=/usr/local perl Makefile.PL PREFIX=/usr/local \
         INC=/usr/local/include  DEFINE=-DOPENSSL_BUILD_UNSAFE=1
   make
   make install
   cd /tmp && o-saft.pl +version
SSLeay.xs needs to be changed as follows:
  • search for
   #ifndef OPENSSL_NO_SSL2
   #if OPENSSL_VERSION_NUMBER < 0x10000000L
 
   const SSL_METHOD *
   SSLv2_method()
 
   #endif
   #endif
 
   #ifndef OPENSSL_NO_SSL3
   #if OPENSSL_VERSION_NUMBER < 0x10002000L

   const SSL_METHOD *
   SSLv3_method()

   #endif
   #endif
  • and replace by
   const SSL_METHOD *
   SSLv2_method()

   const SSL_METHOD *
   SSLv3_method()
Note that Net::SSLeay will be installed in /usr/local/ then. This
can be adapted to your needs by passing another path to the PREFIX
and DESTDIR parameter.
Testing OpenSSL
After installation as descibed above finished, openssl may be tested:
   echo already installed openssl (found with PATH environment)
   openssl ciphers -v
   openssl ciphers -V -ssl2
   openssl ciphers -V -ssl3
   openssl ciphers -V ALL
   openssl ciphers -V ALL:COMPLEMENTOFALL
   openssl ciphers -V ALL:eNULL:EXP
   echo own compiled and installed openssl 
   /usr/local/openssl ciphers -v
   /usr/local/openssl ciphers -V -ssl2
   /usr/local/openssl ciphers -V -ssl3
   /usr/local/openssl ciphers -V ALL
   /usr/local/openssl ciphers -V ALL:COMPLEMENTOFALL
   /usr/local/openssl ciphers -V ALL:eNULL:EXP

The difference should be obvious. Note, the commands using "ALL:COMPLEMENTOFALL" and "ALL:eNULL:EXP" should return the same result.

Testing Net::SSLeay
As we want to test the separately installed Net::SSLeay, it is best
to do it with o-saft.pl itself:
   o-saft.pl +version
we should see a line similar to follwong at the end of the output:
   Net::SSLeay   1.72  /usr/local/lib/x86_64-linux-gnu/perl/5.20.2/Net/SSLeay.pm
Now check for supported (known) ciphers:
   o-saft.pl ciphers -V
we should see lines similar to those of the last /usr/local/openssl
call. However, it should contain more cipher lines.
Stand-alone Executable
Some people asked for a stand-alone executable (mainly for Windows).
Even perl is a scripting language there are situations where a stand-
alone executable would be nice, for example if the installed perl and
its libraries are outdated, or if perl is missing at all.
Currently (2016) there a at least following possibilities to generate
a stand-alone executable:
  • perl with PAR::Packer module
     pp -C -c o-saft.pl
     pp -C -c o-saft.pl -M Net::DNS -M Net::SSLeay -M IO::Socket \
                        -M Net::SSLinfo -M Net::SSLhello
     pp -C -c checkAllCiphers.pl
     pp -C -c checkAllCiphers.pl -M Net::DNS
  • ActiveState perl with its perlapp
     perlapp --clean o-saft.pl
     perlapp --clean o-saft.pl -M Net::DNS -M Net::SSLeay -M IO::Socket \
                 -M Net::SSLinfo -M Net::SSLhello
     perlapp --clean checkAllCiphers.pl
     perlapp --clean checkAllCiphers.pl -M Net::DNS
  • perl2exe from IndigoSTar
     perl2exe o-saft.pl
     perl2exe checkAllCiphers.pl
For details on building the executable, for example how to include
all required modules, please refer to the documentation of the tool.
Note that pre-build executables (build by perlapp, perl2exe) cannot
be provided due to licence problems.
Also note that using stand-alone executable have not been tested the
same way as the o-saft.pl itself. Use them at your own risk.

SEE ALSO

HACKER's INFO

Note on SSL versions
Automatically detecting the supported SSL versions of the underlaying
system is a hard job and not always possible. Reasons could be:
  • used perl modules (Socket::SSL, Net::SSLeay) does not handle errors
properly. Erros may be:
  invalid SSL_version specified at ... IO/Socket/SSL.pm
  Use of uninitialized value in subroutine entry at lib/IO/Socket/SSL.pm
  • the underlaying libssl does not support the version, which then may
result in segmentation fault
  • the underlaying libssl is newer than the perl module and the module
has not been reinstalled. This most often happens with Net::SSLeay
This can be detected with (see version numbers for Net::SSLeay):
   o-saft.pl +version
  • perl (in particular a used module, see above) may bail out with a
compile error, like
   Can't locate auto/Net/SSLeay/CTX_v2_new.al in @INC ...
We try to detect unsupported versions and disable them automatically,
a warning like follwoing is shown then:
   **WARNING: SSL version SSLv2 not supported by openssl
If problems occour with SSL versions, following commands and options
may help to to get closer to the reason or can be used as workaround:
   o-saft.pl +version
   o-saft.pl +version | grep versions
   o-saft.pl +version | grep 0x
   o-saft.pl +protocols your.tld
   o-saft.pl +protocols your.tld --no-rc
If problems occour with SSL versions, following commands and options
Checking for SSL version is done at one place in the code, search for
    supported SSL versions
Using private libssl.so and libcrypt.so
For all cryptographic functionality the libraries installed on the
system will be used. This is in particular perl's Net:SSLeay module,
the system's libssl.so and libcrypt.so and the openssl executable.
It is possible to provide your own libraries, if the perl module and
the executable are linked using dynamic shared objects (aka shared
library, position independent code).
The appropriate option is --lib=PATH .
On most systems these libraries are loaded at startup of the program.
The runtime loader uses a preconfigured list of directories where to
find these libraries. Also most systems provide a special environment
variable to specify additional paths to directories where to search
for libraries, for example the LD_LIBRARY_ variable.
This is the default environment variable used herein. If your system
uses another name it must be specified with the --envlibvar=NAME
option, where NAME is the name of the environment variable.
Understanding --exe=PATH, --lib=PATH, --openssl=FILE
If any of --exe=PATH or --lib=PATH is provided, the pragram calls
(exec) itself recursively with all given options, except the option
itself. The environment variables LD_LIBRARY_PATH and PATH are
set before executing as follows:
  • prepend PATH with all values given with --exe=PATH
  • prepend LD_LIBRARY_PATH with all values given with --lib=PATH
This is exactly, what Cumbersome Approach below describes. So these
option simply provide a shortcut for that.
Note that --openssl=FILE is a full path to the openssl executable
and will not be changed. However, if it is a relative path, it might
be searched for using the previously set PATH (see above).
Note that LD_LIBRARY_PATH is the default. It can be changed with
the --envlibvar=NAME option.
While --exe mainly impacts the openssl executable, --lib also
impacts o-saft.pl itself, as it loads other shared libraries if found.
Bear in mind that all these options can affect the behaviour of the
openssl subsystem, influencing both which executable is called and
which shared libraries will be used.
NOTE that no checks are done if the options are set proper. To verify
the settings, following commands may be used:
   o-saft.pl --lib=YOU-PATH --exe=YOUE-EXE +version
   o-saft.pl --lib=YOU-PATH --exe=YOUE-EXE --v +version
   o-saft.pl --lib=YOU-PATH --exe=YOUE-EXE --v --v +version


Why so many options? Exactly as described above, these options allow
the users to tune the behaviour of the tool to their needs. A common
use case is to enable the use of a separate openssl build independent
of the openssl package used by the operating system. This allows the
user fine grained control over openssl's encryption suites which are
compiled/available, without affecting the core system.
Caveats
Depending on your system and the used modules and executables, it can
be tricky to replace the configured shared libraries with own ones.
Reasons are:
a) the linked library name contains a version number,
b) the linked library uses a fixed path,
c) the linked library is searched at a predefined path,
d) the executable checks the library version when loaded.
Only the first one a) can be circumvented. The last one d) can often
be ignored as it only prints a warning or error message.
To circumvent the "name with version number" problem try following:
  • 1. use ldd (or a similar tool) to get the names used by openssl:
ldd /usr/bin/openssl
which returns something like:
libssl.so.0.9.8 => /lib/libssl.so.0.9.8 (0x00007f940cb6d000)
libcrypto.so.0.9.8 => /lib/libcrypto.so.0.9.8 (0x00007f940c7de000)
libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007f940c5d9000)
libz.so.1 => /lib/x86_64-linux-gnu/libz.so.1 (0x00007f940c3c1000)
libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f940c02c000)
/lib64/ld-linux-x86-64.so.2 (0x00007f940cdea000)
Here only the first two libraries are important. Both, libcrypto.so
and libssl.so need to be version "0.9.8" (in this example).
  • 2. create a directory for your libraries, i.e.:
mkdir /tmp/dada
  • 3. place your libraries there, assuming they are:
/tmp/dada/libssl.so.1.42
/tmp/dada/libcrypto.so.1.42
  • 4. create symbolic links in that directory:
ln -s libssl.so.1.42 libssl.so.0.9.8
ln -s libcrypto.so.1.42 libcrypto.so.0.9.8
  • 5. test program with following option:
   o-saft.pl +libversion --lib=/tmp/dada
   o-saft.pl +list --v   --lib=/tmp/dada
or:
   o-saft.pl +libversion --lib=/tmp/dada -exe=/path/to-openssl
   o-saft.pl +list --v   --lib=/tmp/dada -exe=/path/to-openssl
  • 6. start program with your options, i.e.:
   o-saft.pl --lib=/tmp/dada +ciphers
This works if openssl(1) uses the same shared libraries as
Net:SSLeay(1), which most likely is the case.
It's tested with Unix/Linux only. It may work on other platforms also
if they support such an environment variable and the installed
Net::SSLeay(1) and openssl(1) are linked using dynamic shared
objects.
Depending on compile time settings and/or the location of the used
tool or lib, a warning like following may occur:
  WARNING: can't open config file: /path/to/openssl/ssl/openssl.cnf
This warning can be ignored, usually as req or ca sub commands of
openssl is not used here.
To fix the problem, either use --openssl-cnf=FILE option or set the
the environment variable OPENSSL_CONF properly.
Cumbersome Approach
A more cumbersome approach to call this program is to set following
environment variables in your shell:
  PATH=/tmp/dada-1.42/apps:$PATH
  LD_LIBRARY_PATH=/tmp/dada-1.42
Windows Caveats
I.g. the used libraries on Windows are libeay32.dll and ssleay32.dll.
Windows also supports the LD_LIBRARY_PATH environment variable. If it
does not work as expected with that variable, it might be possible to
place the libs in the same directory as the corresponding executable
(which is found by the PATH environment variable).
Using CGI mode
This script can be used as CGI application. Output is the same as in
common CLI mode, using 'Content-Type:text/plain'. Keep in mind that
the used modules like Net::SSLeay will write some debug messages
on STDERR instead STDOUT. Therefore multiple --v and/or --trace
options behave slightly different.
No additional external files like RC-FILE or DEBUG-FILE are read
in CGI mode; they are silently ignored.
Some options are disabled in CGI mode because they are dangerous or
don't make any sense.
WARNING
There are no input data validation checks implemented herein. All
input data is url-decoded once and then used verbatim.
More advanced checks must be done outside before calling this tool.
It's not recommended to run this tool in CGI mode.
You have been warned!
Using user specified code
There are some functions called within the program flow, which can be
filled with any perl code. Empty stubs of the functions are prepared
in o-saft-usr.pm. See also USER-FILE.

DEBUG

Debugging, Tracing
Following options and commands are useful for hunting problems with
SSL connections and/or this tool. Note that some options can be given
multiple times to increase amount of listed information. Also keep in
mind that it's best to specify --v as very first argument.
Note that the file o-saft-dbx.pm is required, if any --trace*
or --v option is used.
Commands
  • +dump
  • +libversion
  • +s_client
  • +todo
  • +version
Options
  • --v
  • --v--
  • --trace
  • --trace-arg
  • --trace-cmd
  • --trace-key
Empty or undefined strings are written as <<undefined>> in texts.
Some parameters, in particular those of HTTP responses, are written
as <<response>>. Long parameter lists are abbreviated with ....
Output
When using --v and/or --trace options, additional output will
be prefixed with a # (mainly as first, left-most character.
Following formats are used:
  • #<space>
Addition text for verbosity (--v options).
  • #[variable name]<TAB>
Internal variable name (--trace-key options).
  • #o-saft.pl::
  • #Net::SSLinfo::
Trace information for --trace options.
  • #{
Trace information from NET::SSLinfo for --trace options.
These are data lines in the format: #{ variable name : value #}
Note that value here can span multiple lines and ends with #}

EXAMPLES

($0 in all following examples is the name of the tool)
General
   o-saft.pl +cipher some.tld
   o-saft.pl +info   some.tld
   o-saft.pl +check  some.tld
   o-saft.pl +quick  some.tld
   o-saft.pl +help=commands
   o-saft.pl +list
   o-saft.pl +list --v
   o-saft.pl +certificate  some.tld
   o-saft.pl +fingerprint  some.tld 444
   o-saft.pl +after +dates some.tld
Some Specials
  • Get an idea how messages look like
   o-saft.pl +check --cipher=RC4 some.tld
  • Check for Server Name Indication (SNI) usage only
   o-saft.pl +sni some.tld
  • Check for SNI and print certificate's subject and altname
   o-saft.pl +sni +cn +altname some.tld
  • Check for all SNI, certificate's subject and altname issues
   o-saft.pl +sni_check some.tld
  • Only print supported ciphers
   o-saft.pl +cipher --enabled some.tld
  • Only print unsupported ciphers
   o-saft.pl +cipher --disabled some.tld
  • Test for a specific ciphers
   o-saft.pl +cipher --cipher=ADH-AES256-SHA some.tld
  • Test all ciphers, even if not supported by local SSL implementation
   o-saft.pl +cipherall some.tld
   o-saft.pl +cipherall some.tld --range=full
   checkAllCiphers.pl example.tld --range=full --v
  • Show supported (enabled) ciphers with their DH parameters:
   o-saft.pl +cipher-dh some.tld
  • Test using a private libssl.so, libcrypto.so and openssl
   o-saft.pl +cipher --lib=/foo/bar-1.42 --exe=/foo/bar-1.42/apps some.tld
  • Test using a private openssl
   o-saft.pl +cipher --openssl=/foo/bar-1.42/openssl some.tld
  • Test using a private openssl also for testing supported ciphers
   o-saft.pl +cipher --openssl=/foo/bar-1.42/openssl --force-openssl some.tld
  • Show current score settings
   o-saft.pl --help=score
  • Change a single score setting
   o-saft.pl --cfg_score=http_https=42   +check some.tld 
  • Use your private score settings from a file
   o-saft.pl --help=score > magic.score
# edit as needed: magic.score
   o-saft.pl --cfg_score    magic.score  +check some.tld
  • Use your private texts in output
   o-saft.pl +check some.tld --cfg_text=desc=my special description
  • Use your private texts from RC-FILE
   o-saft.pl --help=cfg_text >> .o-saft.pl
# edit as needed: .o-saft.pl
   o-saft.pl +check some.tld
  • Use your private hint texts in output
   o-saft.pl +check some.tld --cfg-hint=renegotiation="my special hint text"
  • Get the certificate's Common Name for a bunch of servers:
   o-saft.pl +cn example.tld some.tld other.tld
   o-saft.pl +cn example.tld some.tld other.tld --showhost --no-header
  • Generate simple parsable output
   o-saft.pl --legacy=quick --no-header +info  some.tld
   o-saft.pl --legacy=quick --no-header +check some.tld
   o-saft.pl --legacy=quick --no-header --trace-key +info  some.tld
   o-saft.pl --legacy=quick --no-header --trace-key +check some.tld
  • Generate simple parsable output for multiple hosts
   o-saft.pl --legacy=quick --no-header --trace-key --showhost +check some.tld other.tld
  • Just for curiosity
   o-saft.pl some.tld +fingerprint --format=raw
   o-saft.pl some.tld +certificate --format=raw | openssl x509 -noout -fingerprint
Specials for hunting problems with connections etc.
  • Show command line argument processing
   o-saft.pl +info some.tld --trace-arg
  • Simple tracing
   o-saft.pl +cn   some.tld --trace
   o-saft.pl +info some.tld --trace
  • A bit more tracing
   o-saft.pl +cn   some.tld --trace --trace
  • Show internal variable names in output
   o-saft.pl +info some.tld --trace-key
  • Show internal argument processeing
   o-saft.pl +info --trace-arg some.tld
  • Show internal control flow and timing
   o-saft.pl +info some.tld --trace-time
  • List checked ciphers
   o-saft.pl +cipher some.tld --v --v
  • List checked ciphers one per line
   o-saft.pl +cipher some.tld --v --v -v
  • Show processing of ciphers
   o-saft.pl +cipher some.tld --v --v --v -v
  • Show values retrieved from target certificate directly
   o-saft.pl +info some.tld --no-cert --no-cert --no-cert-text=Value-from-Certificate
  • Show certificate CA verifications
   o-saft.pl some.tld +chain_verify +verify +error_verify +chain
  • Avoid most performance and timeout problems (don't use --v)
   o-saft.pl +info some.tld --no-cert --no-dns --no-http --no-openssl --no-sni

ATTRIBUTION

Based on ideas (in alphabetical order) of:
cnark.pl, SSLAudit.pl sslscan, ssltest.pl, sslyze.py, testssl.sh
O-Saft - OWASP SSL advanced forensic tool
Thanks to Gregor Kuznik for this title.
cipherraw and most proxy functionality implemented by Torsten Gigler.
For re-writing some docs in proper English, thanks to Robb Watson.
Code to check heartbleed vulnerability adapted from
Steffen Ullrich (08. April 2014):
https://github.com/noxxi/p5-scripts/blob/master/check-ssl-heartbleed.pl
Colouration inspired by https://testssl.sh/ .

AUTHOR

Achim Hoffmann

VERSION

@(#) 16.07.16

Content of this wiki page generated with:

o-saft.pl --no-warning --no-header --help=gen-wiki