Use service account token for authentication (fixes #237)

osbs/core.py

@@ -7,6 +7,7 @@
 """
 from __future__ import print_function, unicode_literals, absolute_import
 import json
+import os
 
 import logging
 from osbs.kerberos_ccache import kerberos_ccache_init
@@ -32,6 +33,11 @@
 
 logger = logging.getLogger(__name__)
 
+# How to authenticate from within a pod
+SERVICEACCOUNT_SECRET = "/var/run/secrets/kubernetes.io/serviceaccount"
+SERVICEACCOUNT_TOKEN = "token"
+SERVICEACCOUNT_CACRT = "ca.crt"
+
 
 def check_response(response):
     if response.status_code not in (httplib.OK, httplib.CREATED):
@@ -66,11 +72,31 @@ def __init__(self, openshift_api_url, openshift_api_version, openshift_oauth_url
         self.kerberos_keytab = kerberos_keytab
         self.kerberos_principal = kerberos_principal
         self.kerberos_ccache = kerberos_ccache
+        self.token = None
+        self.ca = None
         if use_auth is None:
             self.use_auth = bool(use_kerberos or (username and password))
+            if not self.use_auth:
+                # Are we running inside a pod? If so, we will have a
+                # token available which can be used for authentication
+                try:
+                    with open(os.path.join(SERVICEACCOUNT_SECRET,
+                                           SERVICEACCOUNT_TOKEN),
+                              mode='rt') as tfp:
+                        self.token = tfp.read().rstrip()
+
+                    ca = os.path.join(SERVICEACCOUNT_SECRET,
+                                      SERVICEACCOUNT_CACRT)
+                    if os.access(ca, os.R_OK):
+                        self.ca = ca
+                except IOError:
+                    # No token available
+                    pass
+                else:
+                    # We can authenticate using the supplied token
+                    self.use_auth = True
         else:
             self.use_auth = use_auth
-        self.token = None
 
     @property
     def os_oauth_url(self):
@@ -103,6 +129,10 @@ def _request_args(self, with_auth=True, **kwargs):
             else:
                 raise OsbsAuthException("You need to provide both client certificate and key.")
 
+        # Do we have a ca.crt? If so, use it
+        if self.verify_ssl and self.ca is not None:
+            kwargs["ca"] = self.ca
+
         return headers, kwargs
 
     def _post(self, url, with_auth=True, **kwargs):

osbs/http.py

@@ -152,7 +152,7 @@ class HttpStream(object):
     """
 
     def __init__(self, url, method, data=None, kerberos_auth=False,
-                 allow_redirects=True, verify_ssl=True, use_json=False,
+                 allow_redirects=True, verify_ssl=True, ca=None, use_json=False,
                  headers=None, stream=False, username=None, password=None,
                  client_cert=None, client_key=None, verbose=False):
         self.finished = False  # have we read all data?
@@ -192,6 +192,10 @@ def __init__(self, url, method, data=None, kerberos_auth=False,
         self.c.setopt(pycurl.DEBUGFUNCTION, self._curl_debug)
         self.c.setopt(pycurl.SSL_VERIFYPEER, 1 if verify_ssl else 0)
         self.c.setopt(pycurl.SSL_VERIFYHOST, 2 if verify_ssl else 0)
+        if ca:
+            logger.info("Setting CAINFO to %r", ca)
+            self.c.setopt(pycurl.CAINFO, ca)
+
         self.c.setopt(pycurl.VERBOSE, 1 if verbose else 0)
         if username and password:
             username = username.encode('utf-8')