Support reading PEM files in TLSLite

third_party/tlslite/patches/parse_chain.patch

+diff -aurb tlslite-0.3.8/tlslite/X509.py chromium/tlslite/X509.py
+--- tlslite-0.3.8/tlslite/X509.py       Fri Mar 19 18:43:19 2004
++++ chromium/tlslite/X509.py    Wed Feb 29 11:53:54 2012
+@@ -91,6 +91,7 @@
+ 
+         #Create a public key instance
+         self.publicKey = _createPublicRSAKey(n, e)
++        return self
+ 
+     def getFingerprint(self):
+         """Get the hex-encoded fingerprint of this certificate.
+diff -aurb tlslite-0.3.8/tlslite/X509CertChain.py chromium/tlslite/X509CertChain.py
+--- tlslite-0.3.8/tlslite/X509CertChain.py      Fri Mar 19 18:49:58 2004
++++ chromium/tlslite/X509CertChain.py   Wed Feb 29 11:53:42 2012
+@@ -1,6 +1,7 @@
+ """Class representing an X.509 certificate chain."""
+ 
+ from utils import cryptomath
++from X509 import X509
+ 
+ class X509CertChain:
+     """This class represents a chain of X.509 certificates.
+@@ -23,6 +24,66 @@
+             self.x509List = x509List
+         else:
+             self.x509List = []
++
++    def parseChain(self, s):
++        """Parse a PEM-encoded X.509 certificate file chain file.
++
++        @type s: str
++        @param s: A PEM-encoded (eg: Base64) X.509 certificate file, with every
++        certificate wrapped within "-----BEGIN CERTIFICATE-----" and
++        "-----END CERTIFICATE-----" tags). Extraneous data outside such tags,
++        such as human readable representations, will be ignored.
++        """
++
++        class PEMIterator(object):
++            """Simple iterator over PEM-encoded certificates within a string.
++
++            @type data: string
++            @ivar data: A string containing PEM-encoded (Base64) certificates,
++            with every certificate wrapped within "-----BEGIN CERTIFICATE-----"
++            and "-----END CERTIFICATE-----" tags). Extraneous data outside such
++            tags, such as human readable representations, will be ignored.
++
++            @type index: integer
++            @ivar index: The current offset within data to begin iterating from.
++            """
++
++            _CERTIFICATE_HEADER = "----BEGIN CERTIFICATE-----"
++            """The PEM encoding block header for X.509 certificates."""
++
++            _CERTIFICATE_FOOTER = "----END CERTIFICATE-----"
++            """The PEM encoding block footer for X.509 certificates."""
++
++            def __init__(self, s):
++                self.data = s
++                self.index = 0
++
++            def __iter__(self):
++                return self
++
++            def next(self):
++                """Iterates and returns the next L{tlslite.X509.X509}
++                certificate in data.
++
++                @rtype tlslite.X509.X509
++                """
++
++                self.index = self.data.find(self._CERTIFICATE_HEADER,
++                                            self.index)
++                if self.index == -1:
++                    raise StopIteration
++                end = self.data.find(self._CERTIFICATE_FOOTER, self.index)
++                if end == -1:
++                    raise StopIteration
++
++                certStr = self.data[self.index+len(self._CERTIFICATE_HEADER) :
++                                    end]
++                self.index = end + len(self._CERTIFICATE_FOOTER)
++                bytes = cryptomath.base64ToBytes(certStr)
++                return X509().parseBinary(bytes)
++
++        self.x509List = list(PEMIterator(s))
++        return self
+ 
+     def getNumCerts(self):
+         """Get the number of certificates in this chain.