Updated client auditing screen shot.

RFC: JSON output

.gitignore

@@ -6,3 +6,6 @@ venv*/
 .coverage*
 reports/
 .scannerwork/
+pypi/sshaudit/LICENSE
+pypi/sshaudit/README.md
+pypi/sshaudit/sshaudit.py

README.md

@@ -5,10 +5,11 @@
 [![codecov](https://codecov.io/gh/arthepsy/ssh-audit/branch/develop/graph/badge.svg)](https://codecov.io/gh/arthepsy/ssh-audit)
 [![Quality Gate](https://sonarqube.com/api/badges/gate?key=arthepsy-github%3Assh-audit%3Adevelop&template=ROUNDED)](https://sq.evolutiongaming.com/dashboard?id=arthepsy-github%3Assh-audit%3Adevelop)  
 -->
-**ssh-audit** is a tool for ssh server auditing.  
+**ssh-audit** is a tool for ssh server & client configuration auditing.
 
 ## Features
 - SSH1 and SSH2 protocol server support;
+- analyze SSH client configuration;
 - grab banner, recognize device or software and operating system, detect compression;
 - gather key-exchange, host-key, encryption and message authentication code algorithms;
 - output algorithm information (available since, removed/disabled, unsafe/weak/legacy, etc);
@@ -16,11 +17,11 @@
 - output security information (related issues, assigned CVE list, etc);
 - analyze SSH version compatibility based on algorithm information;
 - historical information from OpenSSH, Dropbear SSH and libssh;
-- no dependencies, compatible with Python 2.6+, Python 3.x and PyPy;
+- no dependencies
 
 ## Usage
 ```
-usage: ssh-audit.py [-1246pbnvlt] <host>
+usage: ssh-audit.py [-1246pbcnjvlt] <host>
 
    -1,  --ssh1             force ssh version 1 only
    -2,  --ssh2             force ssh version 2 only
@@ -28,7 +29,11 @@ usage: ssh-audit.py [-1246pbnvlt] <host>
    -6,  --ipv6             enable IPv6 (order of precedence)
    -p,  --port=<port>      port to connect
    -b,  --batch            batch output
+   -c,  --client-audit     starts a server on port 2222 to audit client
+                               software config (use -p to change port;
+                               use -t to change timeout)
    -n,  --no-colors        disable colors
+   -j,  --json             JSON output
    -v,  --verbose          verbose output
    -l,  --level=<level>    minimum output level (info|warn|fail)
    -t,  --timeout=<secs>   timeout (in seconds) for connection and reading
@@ -38,10 +43,24 @@ usage: ssh-audit.py [-1246pbnvlt] <host>
 * batch flag `-b` will output sections without header and without empty lines (implies verbose flag).  
 * verbose flag `-v` will prefix each line with section type and algorithm name.  
 
-### Example
-![screenshot](https://user-images.githubusercontent.com/2982011/63970414-104bdb00-ca72-11e9-832f-3e535be32811.png)
+### Server Audit Example
+Below is a screen shot of the server-auditing output when connecting to an unhardened OpenSSH v5.3 service:
+![screenshot](https://user-images.githubusercontent.com/2982011/64388792-317e6f80-d00e-11e9-826e-a4934769bb07.png)
+
+### Client Audit Example
+Below is a screen shot of the client-auditing output when an unhardened OpenSSH v7.2 client connects:
+![client_screenshot](https://user-images.githubusercontent.com/2982011/68867998-b946c100-06c4-11ea-975f-1f47e4178a74.png)
 
 ## ChangeLog
+### v2.1.0 (2019-11-14)
+ - Added client software auditing functionality (see `-c` / `--client-audit` option).
+ - Added JSON output option (see `-j` / `--json` option; credit [Andreas Jaggi](https://github.com/x-way)).
+ - Fixed crash while scanning Solaris Sun_SSH.
+ - Added 9 new key exchanges: `gss-group1-sha1-toWM5Slw5Ew8Mqkay+al2g==`, `gss-gex-sha1-toWM5Slw5Ew8Mqkay+al2g==`, `gss-group14-sha1-`, `gss-group14-sha1-toWM5Slw5Ew8Mqkay+al2g==`, `gss-group14-sha256-toWM5Slw5Ew8Mqkay+al2g==`, `gss-group15-sha512-toWM5Slw5Ew8Mqkay+al2g==`, `diffie-hellman-group15-sha256`, `ecdh-sha2-1.3.132.0.10`, `curve448-sha512`.
+ - Added 1 new host key type: `ecdsa-sha2-1.3.132.0.10`.
+ - Added 4 new ciphers: `idea-cbc`, `serpent128-cbc`, `serpent192-cbc`, `serpent256-cbc`.
+ - Added 6 new MACs: `hmac-sha2-256-96-etm@openssh.com`, `hmac-sha2-512-96-etm@openssh.com`, `hmac-ripemd`, `hmac-sha256-96@ssh.com`, `umac-32@openssh.com`, `umac-96@openssh.com`.
+
 ### v2.0.0 (2019-08-29)
  - Forked from https://github.com/arthepsy/ssh-audit (development was stalled, and developer went MIA).
  - Added RSA host key length test.
@@ -51,7 +70,7 @@ usage: ssh-audit.py [-1246pbnvlt] <host>
  - Added 5 new key exchanges: `sntrup4591761x25519-sha512@tinyssh.org`, `diffie-hellman-group-exchange-sha256@ssh.com`, `diffie-hellman-group-exchange-sha512@ssh.com`, `diffie-hellman-group16-sha256`, `diffie-hellman-group17-sha512`.
  - Added 3 new encryption algorithms: `des-cbc-ssh1`, `blowfish-ctr`, `twofish-ctr`.
  - Added 10 new MACs: `hmac-sha2-56`, `hmac-sha2-224`, `hmac-sha2-384`, `hmac-sha3-256`, `hmac-sha3-384`, `hmac-sha3-512`, `hmac-sha256`, `hmac-sha256@ssh.com`, `hmac-sha512`, `hmac-512@ssh.com`.
- - Added command line argument (-t / --timeout) for connection & reading timeouts.
+ - Added command line argument (`-t` / `--timeout`) for connection & reading timeouts.
  - Updated CVEs for libssh & Dropbear.
 
 ### v1.7.0 (2016-10-26)

docker_test.sh

@@ -385,24 +385,32 @@ function run_test {
     options=$4
 
     server_exec=
-    test_result=
-    expected_result=
+    test_result_stdout=
+    test_result_json=
+    expected_result_stdout=
+    expected_result_json=
     test_name=
     if [[ $server_type == 'OpenSSH' ]]; then
 	server_exec="/openssh/sshd-${version} -D -f /etc/ssh/sshd_config-${version}_${test_number}"
-	test_result="${TEST_RESULT_DIR}/openssh_${version}_${test_number}.txt"
-	expected_result="test/docker/expected_results/openssh_${version}_${test_number}.txt"
+	test_result_stdout="${TEST_RESULT_DIR}/openssh_${version}_${test_number}.txt"
+	test_result_json="${TEST_RESULT_DIR}/openssh_${version}_${test_number}.json"
+	expected_result_stdout="test/docker/expected_results/openssh_${version}_${test_number}.txt"
+	expected_result_json="test/docker/expected_results/openssh_${version}_${test_number}.json"
 	test_name="OpenSSH ${version} ${test_number}"
 	options=
     elif [[ $server_type == 'Dropbear' ]]; then
 	server_exec="/dropbear/dropbear-${version} -F ${options}"
-	test_result="${TEST_RESULT_DIR}/dropbear_${version}_${test_number}.txt"
-	expected_result="test/docker/expected_results/dropbear_${version}_${test_number}.txt"
+	test_result_stdout="${TEST_RESULT_DIR}/dropbear_${version}_${test_number}.txt"
+	test_result_json="${TEST_RESULT_DIR}/dropbear_${version}_${test_number}.json"
+	expected_result_stdout="test/docker/expected_results/dropbear_${version}_${test_number}.txt"
+	expected_result_json="test/docker/expected_results/dropbear_${version}_${test_number}.json"
 	test_name="Dropbear ${version} ${test_number}"
     elif [[ $server_type == 'TinySSH' ]]; then
 	server_exec="/usr/bin/tcpserver -HRDl0 0.0.0.0 22 /tinysshd/tinyssh-20190101 -v /etc/tinyssh/"
-	test_result="${TEST_RESULT_DIR}/tinyssh_${version}_${test_number}.txt"
-	expected_result="test/docker/expected_results/tinyssh_${version}_${test_number}.txt"
+	test_result_stdout="${TEST_RESULT_DIR}/tinyssh_${version}_${test_number}.txt"
+	test_result_json="${TEST_RESULT_DIR}/tinyssh_${version}_${test_number}.json"
+	expected_result_stdout="test/docker/expected_results/tinyssh_${version}_${test_number}.txt"
+	expected_result_json="test/docker/expected_results/tinyssh_${version}_${test_number}.json"
 	test_name="TinySSH ${version} ${test_number}"
     fi
 
@@ -412,7 +420,14 @@ function run_test {
 	exit 1
     fi
 
-    ./ssh-audit.py localhost:2222 > $test_result
+    ./ssh-audit.py localhost:2222 > $test_result_stdout
+    if [[ $? != 0 ]]; then
+	echo -e "${REDB}Failed to run ssh-audit.py! (exit code: $?)${CLR}"
+	docker container stop $cid > /dev/null
+	exit 1
+    fi
+
+    ./ssh-audit.py -j localhost:2222 > $test_result_json
     if [[ $? != 0 ]]; then
 	echo -e "${REDB}Failed to run ssh-audit.py! (exit code: $?)${CLR}"
 	docker container stop $cid > /dev/null
@@ -429,19 +444,25 @@ function run_test {
     # we need to filter out the banner part of the output so we get stable, repeatable
     # results.
     if [[ $server_type == 'TinySSH' ]]; then
-	grep -v "(gen) banner: " ${test_result} > "${test_result}.tmp"
-	mv "${test_result}.tmp" ${test_result}
+	grep -v "(gen) banner: " ${test_result_stdout} > "${test_result_stdout}.tmp"
+	mv "${test_result_stdout}.tmp" ${test_result_stdout}
+	cat "${test_result_json}" | perl -pe 's/"comments": ".*?"/"comments": ""/' | perl -pe 's/"raw": ".+?"/"raw": ""/' > "${test_result_json}.tmp"
+	mv "${test_result_json}.tmp" ${test_result_json}
     fi
 
-    diff=`diff -u ${expected_result} ${test_result}`
-    if [[ $? == 0 ]]; then
-	echo -e "${test_name} ${GREEN}passed${CLR}."
-    else
+    diff=`diff -u ${expected_result_stdout} ${test_result_stdout}`
+    if [[ $? != 0 ]]; then
 	echo -e "${test_name} ${REDB}FAILED${CLR}.\n\n${diff}\n"
 	exit 1
     fi
-}
 
+    diff=`diff -u ${expected_result_json} ${test_result_json}`
+    if [[ $? != 0 ]]; then
+	echo -e "${test_name} ${REDB}FAILED${CLR}.\n\n${diff}\n"
+	exit 1
+    fi
+    echo -e "${test_name} ${GREEN}passed${CLR}."
+}
 
 
 # First check if docker is functional.

pypi/MANIFEST.in

@@ -0,0 +1 @@
+include sshaudit/LICENSE

pypi/Makefile

@@ -0,0 +1,14 @@
+all:
+	cp ../ssh-audit.py sshaudit/sshaudit.py
+	cp ../LICENSE sshaudit/LICENSE
+	cp ../README.md sshaudit/README.md
+	python3 setup.py sdist bdist_wheel
+
+uploadtest:
+	twine upload --repository-url https://test.pypi.org/legacy/ dist/*
+
+uploadprod:
+	twine upload dist/*
+
+clean:
+	rm -rf build/ dist/ *.egg-info/ sshaudit/sshaudit.py sshaudit/LICENSE sshaudit/README.md

pypi/setup.py

@@ -0,0 +1,38 @@
+# -*- coding: utf-8 -*-
+
+
+import re
+from setuptools import setup
+
+
+version = re.search('^VERSION\s*=\s*\'v(\d\.\d\.\d)\'', open('sshaudit/sshaudit.py').read(), re.M).group(1)
+print("\n\nPackaging ssh-audit v%s...\n\n" % version)
+
+with open("sshaudit/README.md", "rb") as f:
+    long_descr = f.read().decode("utf-8")
+
+
+setup(
+    name = "ssh-audit",
+    packages = ["sshaudit"],
+    license = 'MIT',
+    entry_points = {
+        "console_scripts": ['ssh-audit = sshaudit.sshaudit:main']
+    },
+    version = version,
+    description = "An SSH server configuration security auditing tool",
+    long_description = long_descr,
+    long_description_content_type = "text/markdown",
+    author = "Joe Testa",
+    author_email = "jtesta@positronsecurity.com",
+    url = "https://github.com/jtesta/ssh-audit",
+    classifiers = [
+        "Development Status :: 5 - Production/Stable",
+        "Intended Audience :: Information Technology",
+        "Intended Audience :: System Administrators",
+        "License :: OSI Approved :: MIT License",
+        "Operating System :: OS Independent",
+        "Programming Language :: Python :: 3",
+        "Topic :: Security",
+        "Topic :: Security :: Cryptography"
+    ])

pypi/sshaudit/__main__.py

@@ -0,0 +1,4 @@
+# -*- coding: utf-8 -*-
+
+from .sshaudit import main
+main()

ssh-audit.py

@@ -25,9 +25,10 @@
    THE SOFTWARE.
 """
 from __future__ import print_function
-import binascii, os, io, sys, socket, struct, random, errno, getopt, re, hashlib, base64
+import base64, binascii, errno, hashlib, getopt, io, os, random, re, select, socket, struct, sys, json
 
-VERSION = 'v2.0.0'
+VERSION = 'v2.1.0'
+SSH_HEADER = 'SSH-{0}-OpenSSH_8.0' # SSH software to impersonate
 
 if sys.version_info.major < 3:
         print("\n!!!! NOTE: Python 2 is being considered for deprecation.  If you have a good reason to need continued Python 2 support, please e-mail jtesta@positronsecurity.com with your rationale.\n\n")
@@ -61,7 +62,7 @@ def usage(err=None):
 	uout.head('# {0} {1}, https://github.com/jtesta/ssh-audit\n'.format(p, VERSION))
 	if err is not None and len(err) > 0:
 		uout.fail('\n' + err)
-	uout.info('usage: {0} [-1246pbnvlt] <host>\n'.format(p))
+	uout.info('usage: {0} [-1246pbcnjvlt] <host>\n'.format(p))
 	uout.info('   -h,  --help             print this help')
 	uout.info('   -1,  --ssh1             force ssh version 1 only')
 	uout.info('   -2,  --ssh2             force ssh version 2 only')
@@ -69,7 +70,9 @@ def usage(err=None):
 	uout.info('   -6,  --ipv6             enable IPv6 (order of precedence)')
 	uout.info('   -p,  --port=<port>      port to connect')
 	uout.info('   -b,  --batch            batch output')
+	uout.info('   -c,  --client-audit     starts a server on port 2222 to audit client\n                               software config (use -p to change port;\n                               use -t to change timeout)')
 	uout.info('   -n,  --no-colors        disable colors')
+	uout.info('   -j,  --json             JSON output')
 	uout.info('   -v,  --verbose          verbose output')
 	uout.info('   -l,  --level=<level>    minimum output level (info|warn|fail)')
 	uout.info('   -t,  --timeout=<secs>   timeout (in seconds) for connection and reading\n                               (default: 5)')
@@ -86,18 +89,21 @@ class AuditConf(object):
 		self.ssh1 = True
 		self.ssh2 = True
 		self.batch = False
+		self.client_audit = False
 		self.colors = True
+		self.json = False
 		self.verbose = False
 		self.level = 'info'
 		self.ipvo = ()  # type: Sequence[int]
 		self.ipv4 = False
 		self.ipv6 = False
 		self.timeout = 5.0
+		self.timeout_set = False # Set to True when the user explicitly sets it.
 
 	def __setattr__(self, name, value):
 		# type: (str, Union[str, int, bool, Sequence[int]]) -> None
 		valid = False
-		if name in ['ssh1', 'ssh2', 'batch', 'colors', 'verbose']:
+		if name in ['ssh1', 'ssh2', 'batch', 'client_audit', 'colors', 'verbose', 'timeout_set', 'json']:
 			valid, value = True, True if bool(value) else False
 		elif name in ['ipv4', 'ipv6']:
 			valid = False
@@ -144,10 +150,10 @@ class AuditConf(object):
 		# pylint: disable=too-many-branches
 		aconf = cls()
 		try:
-			sopts = 'h1246p:bnvl:t:'
-			lopts = ['help', 'ssh1', 'ssh2', 'ipv4', 'ipv6', 'port',
-			         'batch', 'no-colors', 'verbose', 'level=', 'timeout=']
-			opts, args = getopt.getopt(args, sopts, lopts)
+			sopts = 'h1246p:bcnjvl:t:'
+			lopts = ['help', 'ssh1', 'ssh2', 'ipv4', 'ipv6', 'port', 'json',
+			         'batch', 'client-audit', 'no-colors', 'verbose', 'level=', 'timeout=']
+			opts, args = getopt.gnu_getopt(args, sopts, lopts)
 		except getopt.GetoptError as err:
 			usage_cb(str(err))
 		aconf.ssh1, aconf.ssh2 = False, False
@@ -168,8 +174,12 @@ class AuditConf(object):
 			elif o in ('-b', '--batch'):
 				aconf.batch = True
 				aconf.verbose = True
+			elif o in ('-c', '--client-audit'):
+				aconf.client_audit = True
 			elif o in ('-n', '--no-colors'):
 				aconf.colors = False
+			elif o in ('-j', '--json'):
+				aconf.json = True
 			elif o in ('-v', '--verbose'):
 				aconf.verbose = True
 			elif o in ('-l', '--level'):
@@ -178,8 +188,10 @@ class AuditConf(object):
 				aconf.level = a
 			elif o in ('-t', '--timeout'):
 				aconf.timeout = float(a)
-		if len(args) == 0:
+				aconf.timeout_set = True
+		if len(args) == 0 and aconf.client_audit == False:
 			usage_cb()
+		if aconf.client_audit == False:
 			if oport is not None:
 				host = args[0]
 			else:
@@ -192,9 +204,13 @@ class AuditConf(object):
 						host, oport = args[0], '22'
 					else:
 						host, oport = s[0], s[1] if len(s) > 1 else '22'
-		port = utils.parse_int(oport)
 			if not host:
 				usage_cb('host is empty')
+		else:
+			host = None
+			if oport is None:
+				oport = '2222'
+		port = utils.parse_int(oport)
 		if port <= 0 or port > 65535:
 			usage_cb('port {0} is not valid'.format(oport))
 		aconf.host = host
@@ -213,6 +229,7 @@ class Output(object):
 		self.batch = False
 		self.verbose = False
 		self.use_colors = True
+		self.json = False
 		self.__level = 0
 		self.__colsupport = 'colorama' in sys.modules or os.name == 'posix'
 	
@@ -303,6 +320,7 @@ class SSH2(object):  # pylint: disable=too-few-public-methods
 		FAIL_DEPRECATED_CIPHER = 'deprecated cipher'
 		FAIL_WEAK_CIPHER      = 'using weak cipher'
 		FAIL_PLAINTEXT        = 'no encryption/integrity'
+		FAIL_DEPRECATED_MAC   = 'deprecated MAC'
 		WARN_CURVES_WEAK      = 'using weak elliptic curves'
 		WARN_RNDSIG_KEY       = 'using weak random number generator could reveal the key'
 		WARN_MODULUS_SIZE     = 'using small 1024-bit modulus'
@@ -312,14 +330,22 @@ class SSH2(object):  # pylint: disable=too-few-public-methods
 		WARN_CIPHER_WEAK      = 'using weak cipher'
 		WARN_ENCRYPT_AND_MAC  = 'using encrypt-and-MAC mode'
 		WARN_TAG_SIZE         = 'using small 64-bit tag size'
+		WARN_TAG_SIZE_96      = 'using small 96-bit tag size'
 		WARN_EXPERIMENTAL     = 'using experimental algorithm'
 		
 		ALGORITHMS = {
                         # Format: 'algorithm_name': [['version_first_appeared_in'], [reason_for_failure1, reason_for_failure2, ...], [warning1, warning2, ...]]
 			'kex': {
 				'diffie-hellman-group1-sha1': [['2.3.0,d0.28,l10.2', '6.6', '6.9'], [FAIL_OPENSSH67_UNSAFE, FAIL_OPENSSH70_LOGJAM], [WARN_MODULUS_SIZE, WARN_HASH_WEAK]],
+				'gss-group1-sha1-toWM5Slw5Ew8Mqkay+al2g==': [[], [FAIL_OPENSSH67_UNSAFE, FAIL_OPENSSH70_LOGJAM], [WARN_MODULUS_SIZE, WARN_HASH_WEAK]],
+				'gss-gex-sha1-toWM5Slw5Ew8Mqkay+al2g==': [[], [], [WARN_HASH_WEAK]],
+				'gss-group14-sha1-': [[], [], [WARN_HASH_WEAK]],
+				'gss-group14-sha1-toWM5Slw5Ew8Mqkay+al2g==': [[], [], [WARN_HASH_WEAK]],
+				'gss-group14-sha256-toWM5Slw5Ew8Mqkay+al2g==': [[]],
+				'gss-group15-sha512-toWM5Slw5Ew8Mqkay+al2g==': [[]],
 				'diffie-hellman-group14-sha1': [['3.9,d0.53,l10.6.0'], [], [WARN_HASH_WEAK]],
 				'diffie-hellman-group14-sha256': [['7.3,d2016.73']],
+				'diffie-hellman-group15-sha256': [[]],
 				'diffie-hellman-group15-sha512': [[]],
 				'diffie-hellman-group16-sha256': [[]],
 				'diffie-hellman-group16-sha512': [['7.3,d2016.73']],
@@ -332,12 +358,16 @@ class SSH2(object):  # pylint: disable=too-few-public-methods
 				'ecdh-sha2-nistp256': [['5.7,d2013.62,l10.6.0'], [WARN_CURVES_WEAK]],
 				'ecdh-sha2-nistp384': [['5.7,d2013.62'], [WARN_CURVES_WEAK]],
 				'ecdh-sha2-nistp521': [['5.7,d2013.62'], [WARN_CURVES_WEAK]],
+				'ecdh-sha2-1.3.132.0.10': [[]], # ECDH over secp256k1 (i.e.: the Bitcoin curve)
 				'curve25519-sha256@libssh.org': [['6.5,d2013.62,l10.6.0']],
-				'curve25519-sha256': [['7.4']],
+				'curve25519-sha256': [['7.4,d2018.76']],
+				'curve448-sha512': [[]],
 				'kexguess2@matt.ucc.asn.au': [['d2013.57']],
 				'rsa1024-sha1': [[], [], [WARN_MODULUS_SIZE, WARN_HASH_WEAK]],
 				'rsa2048-sha256': [[]],
                                 'sntrup4591761x25519-sha512@tinyssh.org': [['8.0'], [], [WARN_EXPERIMENTAL]],
+                                'ext-info-c': [[]], # Extension negotiation (RFC 8308)
+                                'ext-info-s': [[]], # Extension negotiation (RFC 8308)
 			},
 			'key': {
 				'rsa-sha2-256': [['7.2']],
@@ -357,6 +387,7 @@ class SSH2(object):  # pylint: disable=too-few-public-methods
 				'ecdsa-sha2-nistp384-cert-v01@openssh.com': [['5.7'], [WARN_CURVES_WEAK], [WARN_RNDSIG_KEY]],
 				'ecdsa-sha2-nistp521-cert-v01@openssh.com': [['5.7'], [WARN_CURVES_WEAK], [WARN_RNDSIG_KEY]],
 				'ssh-rsa-sha256@ssh.com': [[]],
+				'ecdsa-sha2-1.3.132.0.10': [[], [], [WARN_RNDSIG_KEY]], # ECDSA over secp256k1 (i.e.: the Bitcoin curve)
 			},
 			'enc': {
 				'none': [['1.2.2,d2013.56,l10.2'], [FAIL_PLAINTEXT]],
@@ -374,9 +405,13 @@ class SSH2(object):  # pylint: disable=too-few-public-methods
 				'twofish128-ctr': [['d2015.68']],
 				'twofish192-ctr': [[]],
 				'twofish256-ctr': [['d2015.68']],
+				'serpent128-cbc': [[], [FAIL_DEPRECATED_CIPHER], [WARN_CIPHER_MODE]],
+				'serpent192-cbc': [[], [FAIL_DEPRECATED_CIPHER], [WARN_CIPHER_MODE]],
+				'serpent256-cbc': [[], [FAIL_DEPRECATED_CIPHER], [WARN_CIPHER_MODE]],
 				'serpent128-ctr': [[], [FAIL_DEPRECATED_CIPHER]],
 				'serpent192-ctr': [[], [FAIL_DEPRECATED_CIPHER]],
 				'serpent256-ctr': [[], [FAIL_DEPRECATED_CIPHER]],
+				'idea-cbc': [[], [FAIL_DEPRECATED_CIPHER], [WARN_CIPHER_MODE]],
 				'idea-ctr': [[], [FAIL_DEPRECATED_CIPHER]],
 				'cast128-ctr': [[], [FAIL_DEPRECATED_CIPHER]],
 				'cast128-cbc': [['2.1.0', '6.6', '7.1'], [FAIL_OPENSSH67_UNSAFE], [WARN_OPENSSH72_LEGACY, WARN_CIPHER_MODE, WARN_BLOCK_SIZE]],
@@ -412,23 +447,29 @@ class SSH2(object):  # pylint: disable=too-few-public-methods
 				'hmac-sha3-384': [[], [], [WARN_ENCRYPT_AND_MAC]],
 				'hmac-sha3-512': [[], [], [WARN_ENCRYPT_AND_MAC]],
 				'hmac-sha256': [[], [], [WARN_ENCRYPT_AND_MAC]],
+				'hmac-sha256-96@ssh.com': [[], [], [WARN_ENCRYPT_AND_MAC, WARN_TAG_SIZE]],
 				'hmac-sha256@ssh.com': [[], [], [WARN_ENCRYPT_AND_MAC]],
 				'hmac-sha512': [[], [], [WARN_ENCRYPT_AND_MAC]],
 				'hmac-sha512@ssh.com': [[], [], [WARN_ENCRYPT_AND_MAC]],
 				'hmac-md5': [['2.1.0,d0.28', '6.6', '7.1'], [FAIL_OPENSSH67_UNSAFE], [WARN_OPENSSH72_LEGACY, WARN_ENCRYPT_AND_MAC, WARN_HASH_WEAK]],
 				'hmac-md5-96': [['2.5.0', '6.6', '7.1'], [FAIL_OPENSSH67_UNSAFE], [WARN_OPENSSH72_LEGACY, WARN_ENCRYPT_AND_MAC, WARN_HASH_WEAK]],
+				'hmac-ripemd': [[], [FAIL_DEPRECATED_MAC], [WARN_OPENSSH72_LEGACY, WARN_ENCRYPT_AND_MAC]],
 				'hmac-ripemd160': [['2.5.0', '6.6', '7.1'], [FAIL_OPENSSH67_UNSAFE], [WARN_OPENSSH72_LEGACY, WARN_ENCRYPT_AND_MAC]],
 				'hmac-ripemd160@openssh.com': [['2.1.0', '6.6', '7.1'], [FAIL_OPENSSH67_UNSAFE], [WARN_OPENSSH72_LEGACY, WARN_ENCRYPT_AND_MAC]],
 				'umac-64@openssh.com': [['4.7'], [], [WARN_ENCRYPT_AND_MAC, WARN_TAG_SIZE]],
 				'umac-128@openssh.com': [['6.2'], [], [WARN_ENCRYPT_AND_MAC]],
 				'hmac-sha1-etm@openssh.com': [['6.2'], [], [WARN_HASH_WEAK]],
 				'hmac-sha1-96-etm@openssh.com': [['6.2', '6.6', None], [FAIL_OPENSSH67_UNSAFE], [WARN_HASH_WEAK]],
+				'hmac-sha2-256-96-etm@openssh.com': [[], [], [WARN_TAG_SIZE_96]], # Despite the @openssh.com tag, it doesn't appear that this was ever shipped with OpenSSH; it is only implemented in AsyncSSH (?).
+				'hmac-sha2-512-96-etm@openssh.com': [[], [], [WARN_TAG_SIZE_96]], # Despite the @openssh.com tag, it doesn't appear that this was ever shipped with OpenSSH; it is only implemented in AsyncSSH (?).
 				'hmac-sha2-256-etm@openssh.com': [['6.2']],
 				'hmac-sha2-512-etm@openssh.com': [['6.2']],
 				'hmac-md5-etm@openssh.com': [['6.2', '6.6', '7.1'], [FAIL_OPENSSH67_UNSAFE], [WARN_OPENSSH72_LEGACY, WARN_HASH_WEAK]],
 				'hmac-md5-96-etm@openssh.com': [['6.2', '6.6', '7.1'], [FAIL_OPENSSH67_UNSAFE], [WARN_OPENSSH72_LEGACY, WARN_HASH_WEAK]],
 				'hmac-ripemd160-etm@openssh.com': [['6.2', '6.6', '7.1'], [FAIL_OPENSSH67_UNSAFE], [WARN_OPENSSH72_LEGACY]],
+				'umac-32@openssh.com': [[], [], [WARN_ENCRYPT_AND_MAC, WARN_TAG_SIZE]], # Despite having the @openssh.com suffix, this may never have shipped with OpenSSH (!).
 				'umac-64-etm@openssh.com': [['6.2'], [], [WARN_TAG_SIZE]],
+				'umac-96@openssh.com': [[], [], [WARN_ENCRYPT_AND_MAC]], # Despite having the @openssh.com suffix, this may never have shipped with OpenSSH (!).
 				'umac-128-etm@openssh.com': [['6.2']],
 			}
 		}  # type: Dict[str, Dict[str, List[List[Optional[str]]]]]
@@ -1193,6 +1234,7 @@ class SSH(object):  # pylint: disable=too-few-public-methods
 	class Protocol(object):  # pylint: disable=too-few-public-methods
 		# pylint: disable=bad-whitespace
 		SMSG_PUBLIC_KEY = 2
+		MSG_DEBUG       = 4
 		MSG_KEXINIT     = 20
 		MSG_NEWKEYS     = 21
 		MSG_KEXDH_INIT  = 30
@@ -1207,6 +1249,7 @@ class SSH(object):  # pylint: disable=too-few-public-methods
 		DropbearSSH = 'Dropbear SSH'
 		LibSSH = 'libssh'
 		TinySSH = 'TinySSH'
+		PuTTY = 'PuTTY'
 	
 	class Software(object):
 		def __init__(self, vendor, product, version, patch, os_version):
@@ -1410,6 +1453,9 @@ class SSH(object):  # pylint: disable=too-few-public-methods
 			mx = re.match(r'^tinyssh_(.*)', software)
 			if bool(mx):
 				return cls(None, SSH.Product.TinySSH, mx.group(1), None, None)
+			mx = re.match(r'^PuTTY_Release_(.*)', software)
+			if bool(mx):
+				return cls(None, SSH.Product.PuTTY, mx.group(1), None, None)
 			return None
 	
 	class Banner(object):
@@ -1900,7 +1946,19 @@ class SSH(object):  # pylint: disable=too-few-public-methods
 				['3.0',     '3.0p1',   1, 'CVE-2001-1507',  7.5, 'bypass authentication'],
 				['1.2.3',   '3.0.1p1', 5, 'CVE-2001-0872',  7.2, 'privilege escalation via crafted environment variables'],
 				['1.2.3',   '2.1.1',   1, 'CVE-2001-0361',  4.0, 'recover plaintext from ciphertext'],
-				['1.2',     '2.1',     1, 'CVE-2000-0525', 10.0, 'execute arbitrary code (improper privileges)']]
+				['1.2',     '2.1',     1, 'CVE-2000-0525', 10.0, 'execute arbitrary code (improper privileges)']],
+			'PuTTY': [
+				['0.0', '0.71', 2, 'CVE-2019-XXXX', 5.0, 'undefined vulnerability in obsolete SSHv1 protocol handling'],
+				['0.0', '0.71', 6, 'CVE-2019-XXXX', 5.0, 'local privilege escalation in Pageant'],
+				['0.0', '0.70', 2, 'CVE-2019-9898', 7.5, 'potential recycling of random numbers'],
+				['0.0', '0.70', 2, 'CVE-2019-9897', 5.0, 'multiple denial-of-service issues from writing to the terminal'],
+				['0.0', '0.70', 6, 'CVE-2019-9896', 4.6, 'local application hijacking through malicious Windows help file'],
+				['0.0', '0.70', 2, 'CVE-2019-9894', 6.4, 'buffer overflow in RSA key exchange'],
+				['0.0', '0.69', 6, 'CVE-2016-6167', 4.4, 'local application hijacking through untrusted DLL loading'],
+				['0.0', '0.67', 2, 'CVE-2017-6542', 7.5, 'buffer overflow in UNIX client that can result in privilege escalation or denial-of-service'],
+				['0.0', '0.66', 2, 'CVE-2016-2563', 7.5, 'buffer overflow in SCP command-line utility'],
+				['0.0', '0.65', 2, 'CVE-2015-5309', 4.3, 'integer overflow in terminal-handling code'],
+			]
 		}  # type: Dict[str, List[List[Any]]]
 		TXT = {
 			'Dropbear SSH': [
@@ -1917,16 +1975,17 @@ class SSH(object):  # pylint: disable=too-few-public-methods
 		
 		SM_BANNER_SENT = 1
 		
-		def __init__(self, host, port, ipvo, timeout):
+		def __init__(self, host, port, ipvo, timeout, timeout_set):
 			# type: (Optional[str], int) -> None
 			super(SSH.Socket, self).__init__()
 			self.__sock = None  # type: Optional[socket.socket]
+			self.__sock_map = {}
 			self.__block_size = 8
 			self.__state = 0
 			self.__header = []  # type: List[text_type]
 			self.__banner = None  # type: Optional[SSH.Banner]
-			if host is None:
-				raise ValueError('undefined host')
+#			if host is None:
+#				raise ValueError('undefined host')
 			nport = utils.parse_int(port)
 			if nport < 1 or nport > 65535:
 				raise ValueError('invalid port: {0}'.format(port))
@@ -1937,6 +1996,7 @@ class SSH(object):  # pylint: disable=too-few-public-methods
 			else:
 				self.__ipvo = ()
 			self.__timeout = timeout
+			self.__timeout_set = timeout_set
 
 		
 		def _resolve(self, ipvo):
@@ -1962,6 +2022,65 @@ class SSH(object):  # pylint: disable=too-few-public-methods
 				out.fail('[exception] {0}'.format(e))
 				sys.exit(1)
 
+
+		# Listens on a server socket and accepts one connection (used for
+		# auditing client connections).
+		def listen_and_accept(self):
+
+			try:
+				# Socket to listen on all IPv4 addresses.
+				s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+				s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+				s.bind(('0.0.0.0', self.__port))
+				s.listen()
+				self.__sock_map[s.fileno()] = s
+			except Exception as e:
+				print("Warning: failed to listen on any IPv4 interfaces.")
+				pass
+
+			try:
+				# Socket to listen on all IPv6 addresses.
+				s = socket.socket(socket.AF_INET6, socket.SOCK_STREAM)
+				s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+				s.setsockopt(socket.IPPROTO_IPV6, socket.IPV6_V6ONLY, 1)
+				s.bind(('::', self.__port))
+				s.listen()
+				self.__sock_map[s.fileno()] = s
+			except Exception as e:
+				print("Warning: failed to listen on any IPv6 interfaces.")
+				pass
+
+			# If we failed to listen on any interfaces, terminate.
+			if len(self.__sock_map.keys()) == 0:
+				print("Error: failed to listen on any IPv4 and IPv6 interfaces!")
+				exit(-1)
+
+			# Wait for an incoming connection.  If a timeout was explicitly
+			# set by the user, terminate when it elapses.
+			fds = None
+			time_elapsed = 0.0
+			interval = 1.0
+			while True:
+				# Wait for a connection on either socket.
+				fds = select.select(self.__sock_map.keys(), [], [], interval)
+				time_elapsed += interval
+
+				# We have incoming data on at least one of the sockets.
+				if len(fds[0]) > 0:
+					break
+
+				if self.__timeout_set and time_elapsed >= self.__timeout:
+					print("Timeout elapsed.  Terminating...")
+					exit(-1)
+
+			# Accept the connection.
+			c, addr = self.__sock_map[fds[0][0]].accept()
+			self.client_host = addr[0]
+			self.client_port = addr[1]
+			c.settimeout(self.__timeout)
+			self.__sock = c
+
+
 		def connect(self):
 			# type: () -> None
 			err = None
@@ -1988,15 +2107,15 @@ class SSH(object):  # pylint: disable=too-few-public-methods
 			# type: (int) -> Tuple[Optional[SSH.Banner], List[text_type], Optional[str]]
 			if self.__sock is None:
 				return self.__banner, self.__header, 'not connected'
-			banner = 'SSH-{0}-OpenSSH_7.4'.format('1.5' if sshv == 1 else '2.0')
-			rto = self.__sock.gettimeout()
-			self.__sock.settimeout(0.7)
-			s, e = self.recv()
-			self.__sock.settimeout(rto)
-			if s < 0:
-				return self.__banner, self.__header, e
+			banner = SSH_HEADER.format('1.5' if sshv == 1 else '2.0')
 			if self.__state < self.SM_BANNER_SENT:
 				self.send_banner(banner)
+#			rto = self.__sock.gettimeout()
+#			self.__sock.settimeout(0.7)
+			s, e = self.recv()
+#			self.__sock.settimeout(rto)
+			if s < 0:
+				return self.__banner, self.__header, e
 			e = None
 			while self.__banner is None:
 				if not s > 0:
@@ -2153,6 +2272,8 @@ class SSH(object):  # pylint: disable=too-few-public-methods
 		def __cleanup(self):
 			# type: () -> None
 			self._close_socket(self.__sock)
+			for fd in self.__sock_map:
+				self._close_socket(self.__sock_map[fd])
 			self.__sock = None
 
 
@@ -2200,6 +2321,11 @@ class KexDH(object):  # pragma: nocover
 	# key blob (from which the fingerprint can be calculated).
 	def recv_reply(self, s, parse_host_key_size=True):
 		packet_type, payload = s.read_packet(2)
+
+		# Skip any & all MSG_DEBUG messages.
+		while packet_type == SSH.Protocol.MSG_DEBUG:
+			packet_type, payload = s.read_packet(2)
+
 		if packet_type != -1 and packet_type not in [SSH.Protocol.MSG_KEXDH_REPLY, SSH.Protocol.MSG_KEXDH_GEX_REPLY]:
 			# TODO: change Exception to something more specific.
 			raise Exception('Expected MSG_KEXDH_REPLY (%d) or MSG_KEXDH_GEX_REPLY (%d), but got %d instead.' % (SSH.Protocol.MSG_KEXDH_REPLY, SSH.Protocol.MSG_KEXDH_GEX_REPLY, packet_type))
@@ -2517,10 +2643,14 @@ class KexGroupExchange(KexDH):
 		s.send_packet()
 
 		packet_type, payload = s.read_packet(2)
-		if packet_type != SSH.Protocol.MSG_KEXDH_GEX_GROUP:
+		if (packet_type != SSH.Protocol.MSG_KEXDH_GEX_GROUP) and (packet_type != SSH.Protocol.MSG_DEBUG):
 			# TODO: replace with a better exception type.
 			raise Exception('Expected MSG_KEXDH_GEX_REPLY (%d), but got %d instead.' % (SSH.Protocol.MSG_KEXDH_GEX_REPLY, packet_type))
 
+		# Skip any & all MSG_DEBUG messages.
+		while packet_type == SSH.Protocol.MSG_DEBUG:
+			packet_type, payload = s.read_packet(2)
+
 		# Parse the modulus (p) and generator (g) values from the server.
 		ptr = 0
 		p_len = struct.unpack('>I', payload[ptr:ptr + 4])[0]
@@ -2624,8 +2754,13 @@ def output_algorithm(alg_db, alg_type, alg_name, unknown_algs, alg_max_len=0, al
 				f(' ' * len(prefix + alg_name) + comment)
 
 
-def output_compatibility(algs, for_server=True):
+def output_compatibility(algs, client_audit, for_server=True):
 	# type: (SSH.Algorithms, bool) -> None
+
+	# Don't output any compatibility info if we're doing a client audit.
+	if client_audit:
+		return
+
 	ssh_timeframe = algs.get_ssh_timeframe(for_server)
 	comp_text = []
 	for ssh_prod in [SSH.Product.OpenSSH, SSH.Product.DropbearSSH]:
@@ -2650,7 +2785,7 @@ def output_compatibility(algs, for_server=True):
 		out.good('(gen) compatibility: ' + ', '.join(comp_text))
 
 
-def output_security_sub(sub, software, padlen):
+def output_security_sub(sub, software, client_audit, padlen):
 	# type: (str, Optional[SSH.Software], int) -> None
 	secdb = SSH.Security.CVE if sub == 'cve' else SSH.Security.TXT
 	if software is None or software.product not in secdb:
@@ -2661,9 +2796,11 @@ def output_security_sub(sub, software, padlen):
 			continue
 		target, name = line[2:4]  # type: int, str
 		is_server = target & 1 == 1
-		# is_client = target & 2 == 2
+		is_client = target & 2 == 2
 		# is_local = target & 4 == 4
-		if not is_server:
+
+		# If this security entry applies only to servers, but we're testing a client, then skip it.  Similarly, skip entries that apply only to clients, but we're testing a server.
+		if (is_server and not is_client and client_audit) or (is_client and not is_server and not client_audit):
 			continue
 		p = '' if out.batch else ' ' * (padlen - len(name))
 		if sub == 'cve':
@@ -2679,13 +2816,13 @@ def output_security_sub(sub, software, padlen):
 			out.fail('(sec) {0}{1} -- {2}'.format(name, p, descr))
 
 
-def output_security(banner, padlen):
+def output_security(banner, client_audit, padlen):
 	# type: (Optional[SSH.Banner], int) -> None
 	with OutputBuffer() as obuf:
 		if banner is not None:
 			software = SSH.Software.parse(banner)
-			output_security_sub('cve', software, padlen)
-			output_security_sub('txt', software, padlen)
+			output_security_sub('cve', software, client_audit, padlen)
+			output_security_sub('txt', software, client_audit, padlen)
 	if len(obuf) > 0:
 		out.head('# security')
 		obuf.flush()
@@ -2730,8 +2867,39 @@ def output_fingerprints(algs, sha256=True):
 		out.sep()
 
 
+# Returns True if no warnings or failures encountered in configuration.
 def output_recommendations(algs, software, padlen=0):
 	# type: (SSH.Algorithms, Optional[SSH.Software], int) -> None
+
+	ret = True
+	# PuTTY's algorithms cannot be modified, so there's no point in issuing recommendations.
+	if (software is not None) and (software.product == SSH.Product.PuTTY):
+		max_vuln_version = 0.0
+		max_cvssv2_severity = 0.0
+		# Search the CVE database for the most recent vulnerable version and the max CVSSv2 score.
+		for cve_list in SSH.Security.CVE['PuTTY']:
+			vuln_version = float(cve_list[1])
+			cvssv2_severity = cve_list[4]
+
+			if vuln_version > max_vuln_version:
+				max_vuln_version = vuln_version
+			if cvssv2_severity > max_cvssv2_severity:
+				max_cvssv2_severity = cvssv2_severity
+
+		fn = out.warn
+		if max_cvssv2_severity > 8.0:
+			fn = out.fail
+
+		# Assuming that PuTTY versions will always increment by 0.01, we can calculate the first safe version by adding 0.01 to the latest vulnerable version.
+		current_version = float(software.version)
+		upgrade_to_version = max_vuln_version + 0.01
+		if current_version < upgrade_to_version:
+			out.head('# recommendations')
+			fn('(rec) Upgrade to PuTTY v%.2f' % upgrade_to_version)
+			out.sep()
+			ret = False
+		return ret
+
 	for_server = True
 	with OutputBuffer() as obuf:
 		software, alg_rec = algs.get_recommendations(software, for_server)
@@ -2749,12 +2917,14 @@ def output_recommendations(algs, software, padlen=0):
 						chg_additional_info = ''
 						if action == 'del':
 							an, sg, fn = 'remove', '-', out.warn
+							ret = False
 							if alg_rec[sshv][alg_type][action][name] >= 10:
 								fn = out.fail
 						elif action == 'add':
 							an, sg, fn = 'append', '+', out.good
 						elif action == 'chg':
 							an, sg, fn = 'change', '!', out.fail
+							ret = False
 							chg_additional_info = ' (increase modulus size to 2048 bits or larger)'
 						b = '(SSH{0})'.format(sshv) if sshv == 1 else ''
 						fm = '(rec) {0}{1}{2}-- {3} algorithm to {4}{5} {6}'
@@ -2767,9 +2937,27 @@ def output_recommendations(algs, software, padlen=0):
 		out.head('# algorithm recommendations {0}'.format(title))
 		obuf.flush(True) # Sort the output so that it is always stable (needed for repeatable testing).
 		out.sep()
+	return ret
 
 
-def output(banner, header, kex=None, pkm=None):
+# Output additional information & notes.
+def output_info(algs, software, client_audit, any_problems, padlen=0):
+	with OutputBuffer() as obuf:
+		# Tell user that PuTTY cannot be hardened at the protocol-level.
+		if client_audit and (software is not None) and (software.product == SSH.Product.PuTTY):
+			out.warn('(nfo) PuTTY does not have the option of restricting any algorithms during the SSH handshake.')
+
+		# If any warnings or failures were given, print a link to the hardening guides.
+		if any_problems:
+			out.warn('(nfo) For hardening guides on common OSes, please see: <https://www.ssh-audit.com/hardening_guides.html>')
+
+	if len(obuf) > 0:
+		out.head('# additional info')
+		obuf.flush()
+		out.sep()
+
+
+def output(banner, header, client_audit=False, kex=None, pkm=None):
 	# type: (Optional[SSH.Banner], List[text_type], Optional[SSH2.Kex], Optional[SSH1.PublicKeyMessage]) -> None
 	sshv = 1 if pkm is not None else 2
 	algs = SSH.Algorithms(pkm, kex)
@@ -2788,7 +2976,7 @@ def output(banner, header, kex=None, pkm=None):
 				out.good('(gen) software: {0}'.format(software))
 		else:
 			software = None
-		output_compatibility(algs)
+		output_compatibility(algs, client_audit)
 		if kex is not None:
 			compressions = [x for x in kex.server.compression if x != 'none']
 			if len(compressions) > 0:
@@ -2801,7 +2989,7 @@ def output(banner, header, kex=None, pkm=None):
 		obuf.flush()
 		out.sep()
 	maxlen = algs.maxlen + 1
-	output_security(banner, maxlen)
+	output_security(banner, client_audit, maxlen)
 	unknown_algorithms = []  # Filled in by output_algorithms() with unidentified algs.
 	if pkm is not None:
 		adb = SSH1.KexDB.ALGORITHMS
@@ -2824,7 +3012,9 @@ def output(banner, header, kex=None, pkm=None):
 		title, atype = 'message authentication code algorithms', 'mac'
 		output_algorithms(title, adb, atype, kex.server.mac, unknown_algorithms, maxlen)
 	output_fingerprints(algs, True)
-	output_recommendations(algs, software, maxlen)
+	perfect_config = output_recommendations(algs, software, maxlen)
+	output_info(algs, software, client_audit, not perfect_config)
+
 
 	# If we encountered any unknown algorithms, ask the user to report them.
 	if len(unknown_algorithms) > 0:
@@ -2952,6 +3142,80 @@ class Utils(object):
 		except:  # pylint: disable=bare-except
 			return -1.0
 
+def build_struct(banner, kex=None, pkm=None):
+	res = {
+		"banner": {
+			"raw": str(banner),
+			"protocol": banner.protocol,
+			"software": banner.software,
+			"comments": banner.comments,
+		},
+	}
+	if kex is not None:
+		res['compression'] = kex.server.compression
+
+		res['kex'] = []
+		alg_sizes = kex.dh_modulus_sizes()
+		for algorithm in kex.kex_algorithms:
+			entry = {
+				'algorithm': algorithm,
+			}
+			if (alg_sizes is not None) and (algorithm in alg_sizes):
+				hostkey_size, ca_size = alg_sizes[algorithm]
+				entry['keysize'] = hostkey_size
+				if ca_size > 0:
+					entry['casize'] = ca_size
+			res['kex'].append(entry)
+
+		res['key'] = []
+		alg_sizes = kex.rsa_key_sizes()
+		for algorithm in kex.key_algorithms:
+			entry = {
+				'algorithm': algorithm,
+			}
+			if (alg_sizes is not None) and (algorithm in alg_sizes):
+				hostkey_size, ca_size = alg_sizes[algorithm]
+				entry['keysize'] = hostkey_size
+				if ca_size > 0:
+					entry['casize'] = ca_size
+			res['key'].append(entry)
+
+		res['enc'] = kex.server.encryption
+		res['mac'] = kex.server.mac
+		res['fingerprints'] = []
+		host_keys = kex.host_keys()
+
+		# Normalize all RSA key types to 'ssh-rsa'.  Otherwise, due to Python's order-indifference dictionary types, we would iterate key types in unpredictable orders, which interferes with the docker testing framework (i.e.: tests would fail because elements are reported out of order, even though the output is semantically the same).
+		for host_key_type in host_keys.keys():
+			if host_key_type in SSH2.HostKeyTest.RSA_FAMILY:
+				val = host_keys[host_key_type]
+				del(host_keys[host_key_type])
+				host_keys['ssh-rsa'] = val
+
+		for host_key_type in sorted(host_keys):
+			if host_keys[host_key_type] is None:
+				continue
+
+			fp = SSH.Fingerprint(host_keys[host_key_type])
+
+			# Skip over certificate host types (or we would return invalid fingerprints).
+			if '-cert-' in host_key_type:
+				continue
+			entry = {
+				'type': host_key_type,
+				'fp': fp.sha256,
+			}
+			res['fingerprints'].append(entry)
+	else:
+		res['key'] = ['ssh-rsa1']
+		res['enc'] = pkm.supported_ciphers
+		res['aut'] = pkm.supported_authentications
+		res['fingerprints'] = [{
+			'type': 'ssh-rsa1',
+			'fp': SSH.Fingerprint(pkm.host_key_fingerprint_data).sha256,
+		}]
+
+	return res
 
 def audit(aconf, sshv=None):
 	# type: (AuditConf, Optional[int]) -> None
@@ -2959,7 +3223,10 @@ def audit(aconf, sshv=None):
 	out.verbose = aconf.verbose
 	out.level = aconf.level
 	out.use_colors = aconf.colors
-	s = SSH.Socket(aconf.host, aconf.port, aconf.ipvo, aconf.timeout)
+	s = SSH.Socket(aconf.host, aconf.port, aconf.ipvo, aconf.timeout, aconf.timeout_set)
+	if aconf.client_audit:
+		s.listen_and_accept()
+	else:
 		s.connect()
 	if sshv is None:
 		sshv = 2 if aconf.ssh2 else 1
@@ -3001,16 +3268,27 @@ def audit(aconf, sshv=None):
 		sys.exit(1)
 	if sshv == 1:
 		pkm = SSH1.PublicKeyMessage.parse(payload)
+		if aconf.json:
+			print(json.dumps(build_struct(banner, pkm=pkm), sort_keys=True))
+		else:
 			output(banner, header, pkm=pkm)
 	elif sshv == 2:
 		kex = SSH2.Kex.parse(payload)
+		if aconf.client_audit is False:
 			SSH2.HostKeyTest.run(s, kex)
 			SSH2.GEXTest.run(s, kex)
-		output(banner, header, kex=kex)
+		if aconf.json:
+			print(json.dumps(build_struct(banner, kex=kex), sort_keys=True))
+		else:
+			output(banner, header, client_audit=aconf.client_audit, kex=kex)
 
 
 utils = Utils()
 out = Output()
-if __name__ == '__main__':  # pragma: nocover
+
+def main():
 	conf = AuditConf.from_cmdline(sys.argv[1:], usage)
 	audit(conf)
+
+if __name__ == '__main__':  # pragma: nocover
+	main()

test/docker/expected_results/dropbear_2019.78_test1.json

@@ -0,0 +1 @@
+{"banner": {"comments": null, "protocol": [2, 0], "raw": "SSH-2.0-dropbear_2019.78", "software": "dropbear_2019.78"}, "compression": ["zlib@openssh.com", "none"], "enc": ["aes128-ctr", "aes256-ctr", "aes128-cbc", "aes256-cbc", "3des-ctr", "3des-cbc"], "fingerprints": [{"fp": "SHA256:CDfAU12pjQS7/91kg7gYacza0U/6PDbE04Ic3IpYxkM", "type": "ssh-rsa"}], "kex": [{"algorithm": "curve25519-sha256"}, {"algorithm": "curve25519-sha256@libssh.org"}, {"algorithm": "ecdh-sha2-nistp521"}, {"algorithm": "ecdh-sha2-nistp384"}, {"algorithm": "ecdh-sha2-nistp256"}, {"algorithm": "diffie-hellman-group14-sha256"}, {"algorithm": "diffie-hellman-group14-sha1"}, {"algorithm": "kexguess2@matt.ucc.asn.au"}], "key": [{"algorithm": "ecdsa-sha2-nistp256"}, {"algorithm": "ssh-rsa", "keysize": 1024}, {"algorithm": "ssh-dss"}], "mac": ["hmac-sha1-96", "hmac-sha1", "hmac-sha2-256"]}

test/docker/expected_results/dropbear_2019.78_test1.txt

@@ -1,11 +1,11 @@
 # general
 (gen) banner: SSH-2.0-dropbear_2019.78
 (gen) software: Dropbear SSH 2019.78
-(gen) compatibility: OpenSSH 7.4+ (some functionality from 6.6), Dropbear SSH 2016.73+
+(gen) compatibility: OpenSSH 7.4+ (some functionality from 6.6), Dropbear SSH 2018.76+
 (gen) compression: enabled (zlib@openssh.com)
 
 # key exchange algorithms
-(kex) curve25519-sha256              -- [info] available since OpenSSH 7.4
+(kex) curve25519-sha256              -- [info] available since OpenSSH 7.4, Dropbear SSH 2018.76
 (kex) curve25519-sha256@libssh.org   -- [info] available since OpenSSH 6.5, Dropbear SSH 2013.62
 (kex) ecdh-sha2-nistp521             -- [fail] using weak elliptic curves
                                      `- [info] available since OpenSSH 5.7, Dropbear SSH 2013.62
@@ -80,3 +80,6 @@
 (rec) -diffie-hellman-group14-sha1   -- kex algorithm to remove 
 (rec) -hmac-sha1                     -- mac algorithm to remove 
 
+# additional info
+(nfo) For hardening guides on common OSes, please see: <https://www.ssh-audit.com/hardening_guides.html>
+

test/docker/expected_results/openssh_4.0p1_test1.json

@@ -0,0 +1 @@
+{"banner": {"comments": null, "protocol": [1, 99], "raw": "SSH-1.99-OpenSSH_4.0", "software": "OpenSSH_4.0"}, "compression": ["none", "zlib"], "enc": ["aes128-cbc", "3des-cbc", "blowfish-cbc", "cast128-cbc", "arcfour", "aes192-cbc", "aes256-cbc", "rijndael-cbc@lysator.liu.se", "aes128-ctr", "aes192-ctr", "aes256-ctr"], "fingerprints": [{"fp": "SHA256:YZ457EBcJTSxRKI3yXRgtAj3PBf5B9/F36b1SVooml4", "type": "ssh-rsa"}], "kex": [{"algorithm": "diffie-hellman-group-exchange-sha1", "keysize": 1024}, {"algorithm": "diffie-hellman-group14-sha1"}, {"algorithm": "diffie-hellman-group1-sha1"}], "key": [{"algorithm": "ssh-rsa", "keysize": 1024}, {"algorithm": "ssh-dss"}], "mac": ["hmac-md5", "hmac-sha1", "hmac-ripemd160", "hmac-ripemd160@openssh.com", "hmac-sha1-96", "hmac-md5-96"]}

test/docker/expected_results/openssh_4.0p1_test1.txt

@@ -134,3 +134,6 @@
 (rec) -rijndael-cbc@lysator.liu.se        -- enc algorithm to remove 
 (rec) -ssh-dss                            -- key algorithm to remove 
 
+# additional info
+(nfo) For hardening guides on common OSes, please see: <https://www.ssh-audit.com/hardening_guides.html>
+

test/docker/expected_results/openssh_5.6p1_test1.json

@@ -0,0 +1 @@
+{"banner": {"comments": null, "protocol": [2, 0], "raw": "SSH-2.0-OpenSSH_5.6", "software": "OpenSSH_5.6"}, "compression": ["none", "zlib@openssh.com"], "enc": ["aes128-ctr", "aes192-ctr", "aes256-ctr", "arcfour256", "arcfour128", "aes128-cbc", "3des-cbc", "blowfish-cbc", "cast128-cbc", "aes192-cbc", "aes256-cbc", "arcfour", "rijndael-cbc@lysator.liu.se"], "fingerprints": [{"fp": "SHA256:YZ457EBcJTSxRKI3yXRgtAj3PBf5B9/F36b1SVooml4", "type": "ssh-rsa"}], "kex": [{"algorithm": "diffie-hellman-group-exchange-sha256", "keysize": 1024}, {"algorithm": "diffie-hellman-group-exchange-sha1", "keysize": 1024}, {"algorithm": "diffie-hellman-group14-sha1"}, {"algorithm": "diffie-hellman-group1-sha1"}], "key": [{"algorithm": "ssh-rsa", "keysize": 1024}, {"algorithm": "ssh-dss"}], "mac": ["hmac-md5", "hmac-sha1", "umac-64@openssh.com", "hmac-ripemd160", "hmac-ripemd160@openssh.com", "hmac-sha1-96", "hmac-md5-96"]}

test/docker/expected_results/openssh_5.6p1_test1.txt

@@ -143,3 +143,6 @@
 (rec) -ssh-dss                              -- key algorithm to remove 
 (rec) -diffie-hellman-group14-sha1          -- kex algorithm to remove 
 
+# additional info
+(nfo) For hardening guides on common OSes, please see: <https://www.ssh-audit.com/hardening_guides.html>
+

test/docker/expected_results/openssh_5.6p1_test2.json

@@ -0,0 +1 @@
+{"banner": {"comments": null, "protocol": [2, 0], "raw": "SSH-2.0-OpenSSH_5.6", "software": "OpenSSH_5.6"}, "compression": ["none", "zlib@openssh.com"], "enc": ["aes128-ctr", "aes192-ctr", "aes256-ctr", "arcfour256", "arcfour128", "aes128-cbc", "3des-cbc", "blowfish-cbc", "cast128-cbc", "aes192-cbc", "aes256-cbc", "arcfour", "rijndael-cbc@lysator.liu.se"], "fingerprints": [{"fp": "SHA256:YZ457EBcJTSxRKI3yXRgtAj3PBf5B9/F36b1SVooml4", "type": "ssh-rsa"}], "kex": [{"algorithm": "diffie-hellman-group-exchange-sha256", "keysize": 1024}, {"algorithm": "diffie-hellman-group-exchange-sha1", "keysize": 1024}, {"algorithm": "diffie-hellman-group14-sha1"}, {"algorithm": "diffie-hellman-group1-sha1"}], "key": [{"algorithm": "ssh-rsa", "keysize": 1024}, {"algorithm": "ssh-rsa-cert-v01@openssh.com", "casize": 1024, "keysize": 1024}], "mac": ["hmac-md5", "hmac-sha1", "umac-64@openssh.com", "hmac-ripemd160", "hmac-ripemd160@openssh.com", "hmac-sha1-96", "hmac-md5-96"]}

test/docker/expected_results/openssh_5.6p1_test2.txt

@@ -141,3 +141,6 @@
 (rec) -rijndael-cbc@lysator.liu.se          -- enc algorithm to remove 
 (rec) -diffie-hellman-group14-sha1          -- kex algorithm to remove 
 
+# additional info
+(nfo) For hardening guides on common OSes, please see: <https://www.ssh-audit.com/hardening_guides.html>
+

test/docker/expected_results/openssh_5.6p1_test3.json

@@ -0,0 +1 @@
+{"banner": {"comments": null, "protocol": [2, 0], "raw": "SSH-2.0-OpenSSH_5.6", "software": "OpenSSH_5.6"}, "compression": ["none", "zlib@openssh.com"], "enc": ["aes128-ctr", "aes192-ctr", "aes256-ctr", "arcfour256", "arcfour128", "aes128-cbc", "3des-cbc", "blowfish-cbc", "cast128-cbc", "aes192-cbc", "aes256-cbc", "arcfour", "rijndael-cbc@lysator.liu.se"], "fingerprints": [{"fp": "SHA256:YZ457EBcJTSxRKI3yXRgtAj3PBf5B9/F36b1SVooml4", "type": "ssh-rsa"}], "kex": [{"algorithm": "diffie-hellman-group-exchange-sha256", "keysize": 1024}, {"algorithm": "diffie-hellman-group-exchange-sha1", "keysize": 1024}, {"algorithm": "diffie-hellman-group14-sha1"}, {"algorithm": "diffie-hellman-group1-sha1"}], "key": [{"algorithm": "ssh-rsa", "keysize": 1024}, {"algorithm": "ssh-rsa-cert-v01@openssh.com", "casize": 3072, "keysize": 1024}], "mac": ["hmac-md5", "hmac-sha1", "umac-64@openssh.com", "hmac-ripemd160", "hmac-ripemd160@openssh.com", "hmac-sha1-96", "hmac-md5-96"]}

test/docker/expected_results/openssh_5.6p1_test3.txt

@@ -141,3 +141,6 @@
 (rec) -rijndael-cbc@lysator.liu.se          -- enc algorithm to remove 
 (rec) -diffie-hellman-group14-sha1          -- kex algorithm to remove 
 
+# additional info
+(nfo) For hardening guides on common OSes, please see: <https://www.ssh-audit.com/hardening_guides.html>
+

test/docker/expected_results/openssh_5.6p1_test4.json

@@ -0,0 +1 @@
+{"banner": {"comments": null, "protocol": [2, 0], "raw": "SSH-2.0-OpenSSH_5.6", "software": "OpenSSH_5.6"}, "compression": ["none", "zlib@openssh.com"], "enc": ["aes128-ctr", "aes192-ctr", "aes256-ctr", "arcfour256", "arcfour128", "aes128-cbc", "3des-cbc", "blowfish-cbc", "cast128-cbc", "aes192-cbc", "aes256-cbc", "arcfour", "rijndael-cbc@lysator.liu.se"], "fingerprints": [{"fp": "SHA256:nsWtdJ9Z67Vrf7OsUzQov7esXhsWAfVppArGh25u244", "type": "ssh-rsa"}], "kex": [{"algorithm": "diffie-hellman-group-exchange-sha256", "keysize": 1024}, {"algorithm": "diffie-hellman-group-exchange-sha1", "keysize": 1024}, {"algorithm": "diffie-hellman-group14-sha1"}, {"algorithm": "diffie-hellman-group1-sha1"}], "key": [{"algorithm": "ssh-rsa", "keysize": 3072}, {"algorithm": "ssh-rsa-cert-v01@openssh.com", "casize": 1024, "keysize": 3072}], "mac": ["hmac-md5", "hmac-sha1", "umac-64@openssh.com", "hmac-ripemd160", "hmac-ripemd160@openssh.com", "hmac-sha1-96", "hmac-md5-96"]}

test/docker/expected_results/openssh_5.6p1_test4.txt

@@ -139,3 +139,6 @@
 (rec) -rijndael-cbc@lysator.liu.se          -- enc algorithm to remove 
 (rec) -diffie-hellman-group14-sha1          -- kex algorithm to remove 
 
+# additional info
+(nfo) For hardening guides on common OSes, please see: <https://www.ssh-audit.com/hardening_guides.html>
+

test/docker/expected_results/openssh_5.6p1_test5.json

@@ -0,0 +1 @@
+{"banner": {"comments": null, "protocol": [2, 0], "raw": "SSH-2.0-OpenSSH_5.6", "software": "OpenSSH_5.6"}, "compression": ["none", "zlib@openssh.com"], "enc": ["aes128-ctr", "aes192-ctr", "aes256-ctr", "arcfour256", "arcfour128", "aes128-cbc", "3des-cbc", "blowfish-cbc", "cast128-cbc", "aes192-cbc", "aes256-cbc", "arcfour", "rijndael-cbc@lysator.liu.se"], "fingerprints": [{"fp": "SHA256:nsWtdJ9Z67Vrf7OsUzQov7esXhsWAfVppArGh25u244", "type": "ssh-rsa"}], "kex": [{"algorithm": "diffie-hellman-group-exchange-sha256", "keysize": 1024}, {"algorithm": "diffie-hellman-group-exchange-sha1", "keysize": 1024}, {"algorithm": "diffie-hellman-group14-sha1"}, {"algorithm": "diffie-hellman-group1-sha1"}], "key": [{"algorithm": "ssh-rsa", "keysize": 3072}, {"algorithm": "ssh-rsa-cert-v01@openssh.com", "casize": 3072, "keysize": 3072}], "mac": ["hmac-md5", "hmac-sha1", "umac-64@openssh.com", "hmac-ripemd160", "hmac-ripemd160@openssh.com", "hmac-sha1-96", "hmac-md5-96"]}

test/docker/expected_results/openssh_5.6p1_test5.txt

@@ -137,3 +137,6 @@
 (rec) -rijndael-cbc@lysator.liu.se          -- enc algorithm to remove 
 (rec) -diffie-hellman-group14-sha1          -- kex algorithm to remove 
 
+# additional info
+(nfo) For hardening guides on common OSes, please see: <https://www.ssh-audit.com/hardening_guides.html>
+

test/docker/expected_results/openssh_8.0p1_test1.json

@@ -0,0 +1 @@
+{"banner": {"comments": null, "protocol": [2, 0], "raw": "SSH-2.0-OpenSSH_8.0", "software": "OpenSSH_8.0"}, "compression": ["none", "zlib@openssh.com"], "enc": ["chacha20-poly1305@openssh.com", "aes128-ctr", "aes192-ctr", "aes256-ctr", "aes128-gcm@openssh.com", "aes256-gcm@openssh.com"], "fingerprints": [{"fp": "SHA256:UrnXIVH+7dlw8UqYocl48yUEcKrthGDQG2CPCgp7MxU", "type": "ssh-ed25519"}, {"fp": "SHA256:nsWtdJ9Z67Vrf7OsUzQov7esXhsWAfVppArGh25u244", "type": "ssh-rsa"}], "kex": [{"algorithm": "curve25519-sha256"}, {"algorithm": "curve25519-sha256@libssh.org"}, {"algorithm": "ecdh-sha2-nistp256"}, {"algorithm": "ecdh-sha2-nistp384"}, {"algorithm": "ecdh-sha2-nistp521"}, {"algorithm": "diffie-hellman-group-exchange-sha256", "keysize": 2048}, {"algorithm": "diffie-hellman-group16-sha512"}, {"algorithm": "diffie-hellman-group18-sha512"}, {"algorithm": "diffie-hellman-group14-sha256"}, {"algorithm": "diffie-hellman-group14-sha1"}], "key": [{"algorithm": "rsa-sha2-512", "keysize": 3072}, {"algorithm": "rsa-sha2-256", "keysize": 3072}, {"algorithm": "ssh-rsa", "keysize": 3072}, {"algorithm": "ecdsa-sha2-nistp256"}, {"algorithm": "ssh-ed25519"}], "mac": ["umac-64-etm@openssh.com", "umac-128-etm@openssh.com", "hmac-sha2-256-etm@openssh.com", "hmac-sha2-512-etm@openssh.com", "hmac-sha1-etm@openssh.com", "umac-64@openssh.com", "umac-128@openssh.com", "hmac-sha2-256", "hmac-sha2-512", "hmac-sha1"]}

test/docker/expected_results/openssh_8.0p1_test1.txt

@@ -1,11 +1,11 @@
 # general
 (gen) banner: SSH-2.0-OpenSSH_8.0
 (gen) software: OpenSSH 8.0
-(gen) compatibility: OpenSSH 7.4+, Dropbear SSH 2016.73+
+(gen) compatibility: OpenSSH 7.4+, Dropbear SSH 2018.76+
 (gen) compression: enabled (zlib@openssh.com)
 
 # key exchange algorithms
-(kex) curve25519-sha256                     -- [info] available since OpenSSH 7.4
+(kex) curve25519-sha256                     -- [info] available since OpenSSH 7.4, Dropbear SSH 2018.76
 (kex) curve25519-sha256@libssh.org          -- [info] available since OpenSSH 6.5, Dropbear SSH 2013.62
 (kex) ecdh-sha2-nistp256                    -- [fail] using weak elliptic curves
                                             `- [info] available since OpenSSH 5.7, Dropbear SSH 2013.62
@@ -77,3 +77,6 @@
 (rec) -umac-64-etm@openssh.com              -- mac algorithm to remove 
 (rec) -umac-64@openssh.com                  -- mac algorithm to remove 
 
+# additional info
+(nfo) For hardening guides on common OSes, please see: <https://www.ssh-audit.com/hardening_guides.html>
+

test/docker/expected_results/openssh_8.0p1_test2.json

@@ -0,0 +1 @@
+{"banner": {"comments": null, "protocol": [2, 0], "raw": "SSH-2.0-OpenSSH_8.0", "software": "OpenSSH_8.0"}, "compression": ["none", "zlib@openssh.com"], "enc": ["chacha20-poly1305@openssh.com", "aes128-ctr", "aes192-ctr", "aes256-ctr", "aes128-gcm@openssh.com", "aes256-gcm@openssh.com"], "fingerprints": [{"fp": "SHA256:UrnXIVH+7dlw8UqYocl48yUEcKrthGDQG2CPCgp7MxU", "type": "ssh-ed25519"}], "kex": [{"algorithm": "curve25519-sha256"}, {"algorithm": "curve25519-sha256@libssh.org"}, {"algorithm": "ecdh-sha2-nistp256"}, {"algorithm": "ecdh-sha2-nistp384"}, {"algorithm": "ecdh-sha2-nistp521"}, {"algorithm": "diffie-hellman-group-exchange-sha256", "keysize": 2048}, {"algorithm": "diffie-hellman-group16-sha512"}, {"algorithm": "diffie-hellman-group18-sha512"}, {"algorithm": "diffie-hellman-group14-sha256"}, {"algorithm": "diffie-hellman-group14-sha1"}], "key": [{"algorithm": "ssh-ed25519"}, {"algorithm": "ssh-ed25519-cert-v01@openssh.com"}], "mac": ["umac-64-etm@openssh.com", "umac-128-etm@openssh.com", "hmac-sha2-256-etm@openssh.com", "hmac-sha2-512-etm@openssh.com", "hmac-sha1-etm@openssh.com", "umac-64@openssh.com", "umac-128@openssh.com", "hmac-sha2-256", "hmac-sha2-512", "hmac-sha1"]}

test/docker/expected_results/openssh_8.0p1_test2.txt

@@ -1,11 +1,11 @@
 # general
 (gen) banner: SSH-2.0-OpenSSH_8.0
 (gen) software: OpenSSH 8.0
-(gen) compatibility: OpenSSH 7.4+, Dropbear SSH 2016.73+
+(gen) compatibility: OpenSSH 7.4+, Dropbear SSH 2018.76+
 (gen) compression: enabled (zlib@openssh.com)
 
 # key exchange algorithms
-(kex) curve25519-sha256                     -- [info] available since OpenSSH 7.4
+(kex) curve25519-sha256                     -- [info] available since OpenSSH 7.4, Dropbear SSH 2018.76
 (kex) curve25519-sha256@libssh.org          -- [info] available since OpenSSH 6.5, Dropbear SSH 2013.62
 (kex) ecdh-sha2-nistp256                    -- [fail] using weak elliptic curves
                                             `- [info] available since OpenSSH 5.7, Dropbear SSH 2013.62
@@ -73,3 +73,6 @@
 (rec) -umac-64-etm@openssh.com              -- mac algorithm to remove 
 (rec) -umac-64@openssh.com                  -- mac algorithm to remove 
 
+# additional info
+(nfo) For hardening guides on common OSes, please see: <https://www.ssh-audit.com/hardening_guides.html>
+

test/docker/expected_results/openssh_8.0p1_test3.json

@@ -0,0 +1 @@
+{"banner": {"comments": null, "protocol": [2, 0], "raw": "SSH-2.0-OpenSSH_8.0", "software": "OpenSSH_8.0"}, "compression": ["none", "zlib@openssh.com"], "enc": ["chacha20-poly1305@openssh.com", "aes256-gcm@openssh.com", "aes128-gcm@openssh.com", "aes256-ctr", "aes192-ctr", "aes128-ctr"], "fingerprints": [{"fp": "SHA256:UrnXIVH+7dlw8UqYocl48yUEcKrthGDQG2CPCgp7MxU", "type": "ssh-ed25519"}], "kex": [{"algorithm": "curve25519-sha256"}, {"algorithm": "curve25519-sha256@libssh.org"}, {"algorithm": "diffie-hellman-group-exchange-sha256", "keysize": 2048}], "key": [{"algorithm": "ssh-ed25519"}], "mac": ["hmac-sha2-256-etm@openssh.com", "hmac-sha2-512-etm@openssh.com", "umac-128-etm@openssh.com"]}

test/docker/expected_results/openssh_8.0p1_test3.txt

@@ -1,11 +1,11 @@
 # general
 (gen) banner: SSH-2.0-OpenSSH_8.0
 (gen) software: OpenSSH 8.0
-(gen) compatibility: OpenSSH 7.4+, Dropbear SSH 2013.62+
+(gen) compatibility: OpenSSH 7.4+, Dropbear SSH 2018.76+
 (gen) compression: enabled (zlib@openssh.com)
 
 # key exchange algorithms
-(kex) curve25519-sha256                     -- [info] available since OpenSSH 7.4
+(kex) curve25519-sha256                     -- [info] available since OpenSSH 7.4, Dropbear SSH 2018.76
 (kex) curve25519-sha256@libssh.org          -- [info] available since OpenSSH 6.5, Dropbear SSH 2013.62
 (kex) diffie-hellman-group-exchange-sha256 (2048-bit) -- [info] available since OpenSSH 4.4
 

test/docker/expected_results/tinyssh_20190101_test1.json

@@ -0,0 +1 @@
+{"banner": {"comments": "", "protocol": [2, 0], "raw": "", "software": "tinyssh_noversion"}, "compression": ["none"], "enc": ["chacha20-poly1305@openssh.com"], "fingerprints": [{"fp": "SHA256:89ocln1x7KNqnMgWffGoYtD70ksJ4FrH7BMJHa7SrwU", "type": "ssh-ed25519"}], "kex": [{"algorithm": "curve25519-sha256"}, {"algorithm": "curve25519-sha256@libssh.org"}, {"algorithm": "sntrup4591761x25519-sha512@tinyssh.org"}], "key": [{"algorithm": "ssh-ed25519"}], "mac": ["hmac-sha2-256"]}

test/docker/expected_results/tinyssh_20190101_test1.txt

@@ -1,10 +1,10 @@
 # general
 (gen) software: TinySSH noversion
-(gen) compatibility: OpenSSH 8.0+, Dropbear SSH 2013.62+
+(gen) compatibility: OpenSSH 8.0+, Dropbear SSH 2018.76+
 (gen) compression: disabled
 
 # key exchange algorithms
-(kex) curve25519-sha256                       -- [info] available since OpenSSH 7.4
+(kex) curve25519-sha256                       -- [info] available since OpenSSH 7.4, Dropbear SSH 2018.76
 (kex) curve25519-sha256@libssh.org            -- [info] available since OpenSSH 6.5, Dropbear SSH 2013.62
 (kex) sntrup4591761x25519-sha512@tinyssh.org  -- [warn] using experimental algorithm
                                               `- [info] available since OpenSSH 8.0