Applied patch from GENI by Aaron Helsinger

[sfa.git] / sfa / trust / credential.py

diff --git a/sfa/trust/credential.py b/sfa/trust/credential.py
index 59623f4..f61601a 100644 (file)
--- a/sfa/trust/credential.py
+++ b/sfa/trust/credential.py
@@ -181,6 +181,12 @@ class Signature(object):
         self.gid = gid
 
     def decode(self):
+        # Helper function to pull characters off the front of a string if present
+        def remove_prefix(text, prefix):
+            if text and prefix and text.startswith(prefix):
+                return text[len(prefix):]
+            return text
+
         try:
             doc = parseString(self.xml)
         except ExpatError,e:
@@ -188,14 +194,14 @@ class Signature(object):
             raise
         sig = doc.getElementsByTagName("Signature")[0]
         ## This code until the end of function rewritten by Aaron Helsinger
-        ref_id = sig.getAttribute("xml:id").strip().strip("Sig_")
+        ref_id = remove_prefix(sig.getAttribute("xml:id").strip(), "Sig_")
         # The xml:id tag is optional, and could be in a 
         # Reference xml:id or Reference UID sub element instead
         if not ref_id or ref_id == '':
             reference = sig.getElementsByTagName('Reference')[0]
-            ref_id = reference.getAttribute('xml:id').strip().strip('Sig_')
+            ref_id = remove_prefix(reference.getAttribute('xml:id').strip(), "Sig_")
             if not ref_id or ref_id == '':
-                ref_id = reference.getAttribute('URI').strip().strip('#')
+                ref_id = remove_prefix(reference.getAttribute('URI').strip(), "#")
         self.set_refid(ref_id)
         keyinfos = sig.getElementsByTagName("X509Data")
         gids = None
@@ -299,16 +305,25 @@ class Credential(object):
             else:
                 self.xml = str
                 self.decode()
-
-        # Find an xmlsec1 path
-        self.xmlsec_path = ''
-        paths = ['/usr/bin','/usr/local/bin','/bin','/opt/bin','/opt/local/bin']
-        for path in paths:
-            if os.path.isfile(path + '/' + 'xmlsec1'):
-                self.xmlsec_path = path + '/' + 'xmlsec1'
-                break
-        if not self.xmlsec_path:
-            logger.warn("Could not locate binary for xmlsec1 - SFA will be unable to sign stuff !!")
+        # not strictly necessary but won't hurt either
+        self.get_xmlsec1_path()
+
+    @staticmethod
+    def get_xmlsec1_path():
+        if not getattr(Credential, 'xmlsec1_path', None):
+            # Find a xmlsec1 binary path
+            Credential.xmlsec1_path = ''
+            paths = ['/usr/bin', '/usr/local/bin', '/bin', '/opt/bin', '/opt/local/bin']
+            try:     paths += os.getenv('PATH').split(':')
+            except:  pass
+            for path in paths:
+                xmlsec1 = os.path.join(path, 'xmlsec1')
+                if os.path.isfile(xmlsec1):
+                    Credential.xmlsec1_path = xmlsec1
+                    break
+        if not Credential.xmlsec1_path:
+            logger.error("Could not locate required binary 'xmlsec1' - SFA will be unable to sign stuff !!")
+        return Credential.xmlsec1_path
 
     def get_subject(self):
         if not self.gidObject:
@@ -683,8 +698,11 @@ class Credential(object):
         # Call out to xmlsec1 to sign it
         ref = 'Sig_%s' % self.get_refid()
         filename = self.save_to_random_tmp_file()
-        command='%s --sign --node-id "%s" --privkey-pem %s,%s %s' \
-            % (self.xmlsec_path, ref, self.issuer_privkey, ",".join(gid_files), filename)
+        xmlsec1 = self.get_xmlsec1_path()
+        if not xmlsec1:
+            raise Exception("Could not locate required 'xmlsec1' program")
+        command = '%s --sign --node-id "%s" --privkey-pem %s,%s %s' \
+            % (xmlsec1, ref, self.issuer_privkey, ",".join(gid_files), filename)
 #        print 'command',command
         signed = os.popen(command).read()
         os.remove(filename)
@@ -881,7 +899,10 @@ class Credential(object):
             #cert_args = " ".join(['--trusted-pem %s' % x for x in trusted_certs])
             #command = '{} --verify --node-id "{}" {} {} 2>&1'.\
             #          format(self.xmlsec_path, ref, cert_args, filename)
-            command = [ self.xmlsec_path, '--verify', '--node-id', ref ]
+            xmlsec1 = self.get_xmlsec1_path()
+            if not xmlsec1:
+                raise Exception("Could not locate required 'xmlsec1' program")
+            command = [ xmlsec1, '--verify', '--node-id', ref ]
             for trusted in trusted_certs:
                 command += ["--trusted-pem", trusted ]
             command += [ filename ]