slaprunner: publish a ssh:// url

Instead of having to copy and paste the "ssh command", having a
clickable link is more user friendly. This integrates seamlessly with
ChromeOS secure shell app (eventhough the app does not do anything with
fingerprint as per version 0.19)

software/slaprunner/buildout.hash.cfg

@@ -18,7 +18,7 @@ md5sum = c44a7481bb85e3258128afe3fcf23f44
 
 [template-runner]
 filename = instance-runner.cfg
-md5sum = 67bfce2889be79f12da13fe9996b4f4b
+md5sum = 0b71f354260ab48615ed62c1c8ffc9d4
 
 [template-runner-import-script]
 filename = template/runner-import.sh.jinja2

software/slaprunner/instance-runner.cfg

@@ -326,6 +326,27 @@ recipe = slapos.cookbook:dropbear.add_authorized_key
 home = $${buildout:directory}
 key = $${slap-parameter:user-authorized-key}
 
+[runner-sshkeys-publickey-fingerprint-cmd]
+recipe = plone.recipe.command
+command = $${runner-sshkeys-authority:keygen-binary} -lf $${runner-sshkeys-sshd:public-key} | cut  -f 2 -d\ | sed 's/+/%2B/g' | sed 's/\//%2F/g' | sed 's/SHA256://'
+
+[runner-sshkeys-publickey-fingerprint-shelloutput]
+recipe = collective.recipe.shelloutput
+# XXX because collective.recipe.shelloutput ignore errors, we run the same
+# command in a plone.recipe.command so that if fails if something goes wrong.
+commands =
+  fingerprint = $${runner-sshkeys-publickey-fingerprint-cmd:command}
+
+[runner-sshkeys-publickey-fingerprint]
+# fingerprint for ssh url, see
+# https://tools.ietf.org/id/draft-salowey-secsh-uri-00.html#connparam
+# https://winscp.net/eng/docs/session_url#hostkey
+
+# format is host-key-alg-fingerprint, but we know that
+# $${runner-sshkeys-sshd:public-key} is rsa so for host-key-alg
+# we just use use rsa.
+fingerprint = ssh-rsa-$${runner-sshkeys-publickey-fingerprint-shelloutput:fingerprint}
+
 #---------------------------
 #--
 #-- Set nginx frontend
@@ -612,6 +633,7 @@ backend-url = $${slaprunner:access-url}
 init-user = $${runner-htpasswd:user}
 init-password = $${runner-htpasswd:password}
 ssh-command = ssh $${user-info:pw-name}@$${slap-network-information:global-ipv6} -p $${runner-sshd-port:port}
+ssh-url = ssh://$${user-info:pw-name};fingerprint=$${runner-sshkeys-publickey-fingerprint:fingerprint}@[$${slap-network-information:global-ipv6}]:$${runner-sshd-port:port}
 git-public-url = https://[$${httpd-parameters:global_ip}]:$${httpd-parameters:global_port}/git-public/
 git-private-url = https://[$${httpd-parameters:global_ip}]:$${httpd-parameters:global_port}/git/
 monitor-base-url = $${monitor-publish-parameters:monitor-base-url}

software/slaprunner/software.cfg

@@ -140,6 +140,7 @@ eggs =
   erp5.util
   lock-file
   plone.recipe.command
+  collective.recipe.shelloutput
   slapos.recipe.build
   slapos.toolbox[flask_auth]
   gunicorn==19.7.1
@@ -162,6 +163,7 @@ gunicorn = 19.7.1
 prettytable = 0.7.2
 pycurl = 7.43.0
 slapos.recipe.template = 4.3
+collective.recipe.shelloutput = 0.1
 collective.recipe.environment = 0.2.0
 smmap = 0.9.0
 lockfile = 0.12.2

software/slaprunner/test/setup.py

@@ -47,6 +47,8 @@ setup(name=name,
           'erp5.util',
           'supervisor',
           'psutil',
+          'paramiko',
+          'six',
       ],
       zip_safe=True,
       test_suite='test',

software/slaprunner/test/test.py

@@ -26,6 +26,12 @@
 ##############################################################################
 
 import os
+import paramiko
+import contextlib
+import base64
+import hashlib
+from six.moves.urllib.parse import urlparse
+from six.moves.urllib.parse import quote
 
 from slapos.recipe.librecipe import generateHashFromFiles
 from slapos.testing.testcase import makeModuleSetUpAndTestCaseClass
@@ -40,6 +46,82 @@ class SlaprunnerTestCase(SlapOSInstanceTestCase):
   __partition_reference__ = 's'
 
 
+class TestSSH(SlaprunnerTestCase):
+  @classmethod
+  def getInstanceParameterDict(cls):
+    cls.ssh_key = paramiko.RSAKey.generate(1024)
+    return {
+        'user-authorized-key': 'ssh-rsa {}'.format(cls.ssh_key.get_base64())
+    }
+
+  def test_connect(self):
+    parameter_dict = self.computer_partition.getConnectionParameterDict()
+    ssh_url = parameter_dict['ssh-url']
+    parsed = urlparse(ssh_url)
+    self.assertEqual('ssh', parsed.scheme)
+
+    # username contain a fingerprint (only, so we simplify the parsing)
+    #
+    # relevant parts of hte grammar defined in
+    # https://tools.ietf.org/id/draft-salowey-secsh-uri-00.html
+    #
+    #   ssh-info      =  [ userinfo ] [";" c-param *("," c-param)]
+    #   c-param       =  paramname "=" paramvalue
+    ssh_info = parsed.username
+    username, fingerprint_from_url = ssh_info.split(';fingerprint=')
+    client = paramiko.SSHClient()
+
+    self.assertTrue(fingerprint_from_url.startswith('ssh-rsa-'), '')
+    fingerprint_from_url = fingerprint_from_url[len('ssh-rsa-'):]
+
+    class KeyPolicy(object):
+      """Accept server key and keep it in self.key for inspection
+      """
+      def missing_host_key(self, client, hostname, key):
+        self.key = key
+
+    key_policy = KeyPolicy()
+    client.set_missing_host_key_policy(key_policy)
+
+    with contextlib.closing(client):
+      client.connect(
+          username=username,
+          hostname=parsed.hostname,
+          port=parsed.port,
+          pkey=self.ssh_key,
+      )
+      # Check fingerprint from server matches the published one.
+      # Paramiko does not allow to get the fingerprint as SHA256 easily yet
+      # https://github.com/paramiko/paramiko/pull/1103
+      self.assertEqual(
+          fingerprint_from_url,
+          quote(
+              # base64 encoded fingerprint adds an extra = at the end
+              base64.b64encode(
+                  hashlib.sha256(key_policy.key.asbytes()).digest())[:-1],
+              # also encode /
+              safe=''))
+
+      # Check shell is usable
+      channel = client.invoke_shell()
+      channel.settimeout(30)
+      received = ''
+      while True:
+        r = channel.recv(1024)
+        self.logger.debug("received >%s<", r)
+        if not r:
+          break
+        received += r
+        if 'slaprunner shell' in received:
+          break
+      self.assertIn("Welcome to SlapOS slaprunner shell", received)
+
+      # simple commands can also be executed ( this would be like `ssh bash -c 'cd; pwd'` )
+      self.assertEqual(
+          self.computer_partition_root_path,
+          client.exec_command("pwd")[1].read(1000).strip())
+
+
 class ServicesTestCase(SlaprunnerTestCase):
   def test_hashes(self):
     hash_files = [