Update tlslite to 0.4.6.

third_party/tlslite/tlslite/utils/pem.py

+# Author: Trevor Perrin
+# See the LICENSE file for legal information regarding use of this file.
+
+from .compat import *
+import binascii
+
+#This code is shared with tackpy (somewhat), so I'd rather make minimal
+#changes, and preserve the use of a2b_base64 throughout.
+
+def dePem(s, name):
+    """Decode a PEM string into a bytearray of its payload.
+    
+    The input must contain an appropriate PEM prefix and postfix
+    based on the input name string, e.g. for name="CERTIFICATE":
+
+    -----BEGIN CERTIFICATE-----
+    MIIBXDCCAUSgAwIBAgIBADANBgkqhkiG9w0BAQUFADAPMQ0wCwYDVQQDEwRUQUNL
+...
+    KoZIhvcNAQEFBQADAwA5kw==
+    -----END CERTIFICATE-----    
+
+    The first such PEM block in the input will be found, and its
+    payload will be base64 decoded and returned.
+    """
+    prefix  = "-----BEGIN %s-----" % name
+    postfix = "-----END %s-----" % name    
+    start = s.find(prefix)
+    if start == -1:
+        raise SyntaxError("Missing PEM prefix")
+    end = s.find(postfix, start+len(prefix))
+    if end == -1:
+        raise SyntaxError("Missing PEM postfix")
+    s = s[start+len("-----BEGIN %s-----" % name) : end]
+    retBytes = a2b_base64(s) # May raise SyntaxError
+    return retBytes
+    
+def dePemList(s, name):
+    """Decode a sequence of PEM blocks into a list of bytearrays.
+
+    The input must contain any number of PEM blocks, each with the appropriate
+    PEM prefix and postfix based on the input name string, e.g. for
+    name="TACK BREAK SIG".  Arbitrary text can appear between and before and
+    after the PEM blocks.  For example:
+
+    " Created by TACK.py 0.9.3 Created at 2012-02-01T00:30:10Z -----BEGIN TACK
+    BREAK SIG-----
+    ATKhrz5C6JHJW8BF5fLVrnQss6JnWVyEaC0p89LNhKPswvcC9/s6+vWLd9snYTUv
+    YMEBdw69PUP8JB4AdqA3K6Ap0Fgd9SSTOECeAKOUAym8zcYaXUwpk0+WuPYa7Zmm
+    SkbOlK4ywqt+amhWbg9txSGUwFO5tWUHT3QrnRlE/e3PeNFXLx5Bckg= -----END TACK
+    BREAK SIG----- Created by TACK.py 0.9.3 Created at 2012-02-01T00:30:11Z
+    -----BEGIN TACK BREAK SIG-----
+    ATKhrz5C6JHJW8BF5fLVrnQss6JnWVyEaC0p89LNhKPswvcC9/s6+vWLd9snYTUv
+    YMEBdw69PUP8JB4AdqA3K6BVCWfcjN36lx6JwxmZQncS6sww7DecFO/qjSePCxwM
+    +kdDqX/9/183nmjx6bf0ewhPXkA0nVXsDYZaydN8rJU1GaMlnjcIYxY= -----END TACK
+    BREAK SIG----- "
+    
+    All such PEM blocks will be found, decoded, and return in an ordered list
+    of bytearrays, which may have zero elements if not PEM blocks are found.
+     """
+    bList = []
+    prefix  = "-----BEGIN %s-----" % name
+    postfix = "-----END %s-----" % name
+    while 1:
+        start = s.find(prefix)
+        if start == -1:
+            return bList
+        end = s.find(postfix, start+len(prefix))
+        if end == -1:
+            raise SyntaxError("Missing PEM postfix")
+        s2 = s[start+len(prefix) : end]
+        retBytes = a2b_base64(s2) # May raise SyntaxError
+        bList.append(retBytes)
+        s = s[end+len(postfix) : ]
+
+def pem(b, name):
+    """Encode a payload bytearray into a PEM string.
+    
+    The input will be base64 encoded, then wrapped in a PEM prefix/postfix
+    based on the name string, e.g. for name="CERTIFICATE":
+    
+    -----BEGIN CERTIFICATE-----
+    MIIBXDCCAUSgAwIBAgIBADANBgkqhkiG9w0BAQUFADAPMQ0wCwYDVQQDEwRUQUNL
+...
+    KoZIhvcNAQEFBQADAwA5kw==
+    -----END CERTIFICATE-----    
+    """
+    s1 = b2a_base64(b)[:-1] # remove terminating \n
+    s2 = ""
+    while s1:
+        s2 += s1[:64] + "\n"
+        s1 = s1[64:]
+    s = ("-----BEGIN %s-----\n" % name) + s2 + \
+        ("-----END %s-----\n" % name)     
+    return s
+
+def pemSniff(inStr, name):
+    searchStr = "-----BEGIN %s-----" % name
+    return searchStr in inStr