Dynamic insertion of pubkey to mac_permissions.xml

Support the inseretion of the public key from pem
files into the mac_permissions.xml file at build
time.

Change-Id: Ia42b6cba39bf93723ed3fb85236eb8f80a08962a

1 files changed, 208 insertions, 0 deletions

diff --git a/tools/insertkeys.py b/tools/insertkeys.py
new file mode 100755
index 0000000..e4eeb43
--- /dev/null
+++ b/tools/insertkeys.py
@@ -0,0 +1,208 @@
+#!/usr/bin/env python
+
+from xml.sax import saxutils, handler, make_parser
+from optparse import OptionParser
+import ConfigParser
+import logging
+import base64
+import sys
+import os
+
+__VERSION = (0, 1)
+
+'''
+This tool reads a mac_permissions.xml and replaces keywords in the signature
+clause with keys provided by pem files.
+'''
+
+class GenerateKeys(object):
+    def __init__(self, path):
+        '''
+        Generates an object with Base16 and Base64 encoded versions of the keys
+        found in the supplied pem file argument. PEM files can contain multiple
+        certs, however this seems to be unused in Android as pkg manager grabs
+        the first cert in the APK. This will however support multiple certs in
+        the resulting generation with index[0] being the first cert in the pem
+        file.
+        '''
+
+        self._base64Key = list()
+        self._base16Key = list()
+
+        if not os.path.isfile(path):
+            sys.exit("Path " + path + " does not exist or is not a file!")
+
+        pkFile = open(path, 'rb').readlines()
+        base64Key = ""
+        inCert = False
+        for line in pkFile:
+            if line.startswith("-"):
+                inCert = not inCert
+                continue
+
+            base64Key += line.strip()
+
+        # Base 64 includes uppercase. DO NOT tolower()
+        self._base64Key.append(base64Key)
+
+        # Pkgmanager and setool see hex strings with lowercase, lets be consistent.
+        self._base16Key.append(base64.b16encode(base64.b64decode(base64Key)).lower())
+
+    def __len__(self):
+        return len(self._base16Key)
+
+    def __str__(self):
+        return str(self.getBase16Keys())
+
+    def getBase16Keys(self):
+        return self._base16Key
+
+    def getBase64Keys(self):
+        return self._base64Key
+
+class ParseConfig(ConfigParser.ConfigParser):
+
+    # This must be lowercase
+    OPTION_WILDCARD_TAG = "all"
+
+    def generateKeyMap(self, target_build_variant):
+
+        keyMap = dict()
+
+        for tag in self.sections():
+
+            options = self.options(tag)
+
+            for option in options:
+
+                # Only generate the key map for debug or release,
+                # not both!
+                if option != target_build_variant and \
+                option != ParseConfig.OPTION_WILDCARD_TAG:
+                    logging.info("Skipping " + tag + " : " + option +
+                        " because target build variant is set to " +
+                        str(target_build_variant))
+                    continue
+
+                if tag in keyMap:
+                    sys.exit("Duplicate tag detected " + tag)
+
+                path = self.get(tag, option)
+
+                keyMap[tag] = GenerateKeys(path)
+
+                # Multiple certificates may exist in
+                # the pem file. GenerateKeys supports
+                # this however, the mac_permissions.xml
+                # as well as PMS do not.
+                assert len(keyMap[tag]) == 1
+
+        return keyMap
+
+class ReplaceTags(handler.ContentHandler):
+
+    DEFAULT_TAG = "default"
+    PACKAGE_TAG = "package"
+    POLICY_TAG = "policy"
+    SIGNER_TAG = "signer"
+    SIGNATURE_TAG = "signature"
+
+    TAGS_WITH_CHILDREN = [ DEFAULT_TAG, PACKAGE_TAG, POLICY_TAG, SIGNER_TAG ]
+
+    XML_ENCODING_TAG = '<?xml version="1.0" encoding="iso-8859-1"?>'
+
+    def __init__(self, keyMap, out=sys.stdout):
+
+        handler.ContentHandler.__init__(self)
+        self._keyMap = keyMap
+        self._out = out
+
+    def startDocument(self):
+        self._out.write(ReplaceTags.XML_ENCODING_TAG)
+        self._out.write("<!-- AUTOGENERATED FILE DO NOT MODIFY -->")
+
+    def startElement(self, tag, attrs):
+
+        self._out.write('<' + tag)
+
+        for (name, value) in attrs.items():
+
+            if name == ReplaceTags.SIGNATURE_TAG and value in self._keyMap:
+                for key in self._keyMap[value].getBase16Keys():
+                    logging.info("Replacing " + name + " " + value + " with " + key)
+                    self._out.write(' %s="%s"' % (name, saxutils.escape(key)))
+            else:
+                self._out.write(' %s="%s"' % (name, saxutils.escape(value)))
+
+        if tag in ReplaceTags.TAGS_WITH_CHILDREN:
+            self._out.write('>')
+        else:
+            self._out.write('/>')
+
+    def endElement(self, tag):
+        if tag in ReplaceTags.TAGS_WITH_CHILDREN:
+            self._out.write('</%s>' % tag)
+
+    def characters(self, content):
+        if not content.isspace():
+            self._out.write(saxutils.escape(content))
+
+    def ignorableWhitespace(self, content):
+        pass
+
+    def processingInstruction(self, target, data):
+        self._out.write('<?%s %s?>' % (target, data))
+
+if __name__ == "__main__":
+
+    # Intentional double space to line up equls signs and opening " for
+    # readability.
+    usage  = "usage: %prog [options] CONFIG_FILE MAC_PERMISSIONS_FILE\n"
+    usage += "This tool allows one to configure an automatic inclusion "
+    usage += "of signing keys into the mac_permision.xml file from the "
+    usage += "pem files."
+
+    version = "%prog " + str(__VERSION)
+
+    parser = OptionParser(usage=usage, version=version)
+
+    parser.add_option("-v", "--verbose",
+                      action="store_true", dest="verbose", default=False,
+                      help="Print internal operations to stdout")
+
+    parser.add_option("-o", "--output", default="stdout", dest="output_file",
+                      metavar="FILE", help="Specify an output file, default is stdout")
+
+    parser.add_option("-c", "--cwd", default=os.getcwd(), dest="root",
+                      metavar="DIR", help="Specify a root (CWD) directory to run this from, it" \
+                                          "chdirs' AFTER loading the config file")
+
+    parser.add_option("-t", "--target-build-variant", default="eng", dest="target_build_variant",
+                      help="Specify the TARGET_BUILD_VARIANT, defaults to eng")
+
+
+    (options, args) = parser.parse_args()
+
+    if len(args) != 2:
+        parser.error("Must specify a config file (keys.conf) AND mac_permissions.xml file!")
+
+    logging.basicConfig(level=logging.INFO if options.verbose == True else logging.WARN)
+
+    # Read the config file
+    config = ParseConfig()
+    config.read(args[0])
+
+    os.chdir(options.root)
+
+    output_file = sys.stdout if options.output_file == "stdout" else open(options.output_file, "w")
+    logging.info("Setting output file to: " + options.output_file)
+
+    # Generate the key list
+    key_map = config.generateKeyMap(options.target_build_variant.lower())
+    logging.info("Generate key map:")
+    for k in key_map:
+        logging.info(k + " : " + str(key_map[k]))
+    # Generate the XML file with markup replaced with keys
+    parser = make_parser()
+    parser.setContentHandler(ReplaceTags(key_map, output_file))
+    parser.parse(args[1])