apache & misc work

==================
* added prelim helpers for htpasswd & htdigest
* bugfix to ldap hashes
* added CryptContext.replace() back
* NOTE: all above need UTs and docs

3 files changed, 188 insertions, 15 deletions

diff --git a/passlib/apache.py b/passlib/apache.py
index 9888210..3187612 100644
--- a/passlib/apache.py
+++ b/passlib/apache.py
@@ -1,32 +1,202 @@
-"""
-apache support
+"""passlib.apache - apache password support
+
+.. todo::
+
+    support htpasswd context
+
+    needs ldap_sha1 support
+    detect when crypt should be used, and what ones.
+
+.. todo::
+    support htdigest context
 
-http://httpd.apache.org/docs/2.2/misc/password_encryptions.html
-http://httpd.apache.org/docs/2.0/programs/htpasswd.html
-NOTE: digest format is md5(user ":" realm ":" passwd).hexdigest()
-    file is "user:realm:hash"
+.. todo::
+
+    support reading / writing htpasswd & htdigest files using this module.
+
+    references -
+        http://httpd.apache.org/docs/2.2/misc/password_encryptions.html
+        http://httpd.apache.org/docs/2.0/programs/htpasswd.html
+
+    NOTE: htdigest format is md5(user ":" realm ":" passwd).hexdigest()
+        file format is "user:realm:hash"
 """
 #=========================================================
 #imports
 #=========================================================
 from __future__ import with_statement
 #core
+from hashlib import md5
 import logging; log = logging.getLogger(__name__)
+import os
 #site
 #libs
-from passlib.hash import postgres_md5
 from passlib.base import CryptContext
 #pkg
 #local
 __all__ = [
-    'postgres_md5',
-    'postgres_context',
 ]
 
 #=========================================================
-#db contexts
+#common helpers
+#=========================================================
+class _CommonFile(object):
+    "helper for HtpasswdFile / HtdigestFile"
+
+    def __init__(self, path, create=False):
+        self.path = path
+        if create:
+            self._entry_order = []
+            self._entry_map = {}
+            self.mtime = 0
+        else:
+            self.load()
+
+    def reload(self):
+        "load only if file has changed; throw error if file not found"
+        if self.mtime and self.mtime == os.path.getmtime(self.path):
+            return False
+        self.load()
+        return True
+
+    def load(self):
+        "load entries from file; throw error if file not found or malformed"
+        pl = self._parse_line
+        with file(self.path, "rU") as fh:
+            self.mtime = os.path.getmtime(self.path)
+            entry_order = self._entry_order = []
+            entry_map = self._entry_map = {}
+            for line in fh:
+                key, value = pl(line)
+                if key in entry_map:
+                    #XXX: should we use data from first entry, or last entry?
+                    #     going w/ first entry for now.
+                    continue
+                entry_order.append(key)
+                entry_map[key] = value
+        return True
+
+    #subclass: _parse_line(line) -> (key, hash)
+
+    def save(self):
+        "save entries to file"
+        rl = self._render_line
+        entry_order = self._entry_order
+        entry_map = self._entry_map
+        assert len(entry_order) == len(entry_map), "internal error in entry list"
+        with file(self.path, "wb") as fh:
+            fh.writelines(rl(key, entry_map[key]) for key in entry_order)
+            self.mtime = os.path.getmtime(self.path)
+
+    #subclass: _render_line(entry) -> line
+
+    def _update_key(self, key, value):
+        entry_map = self._entry_map
+        if key in entry_map:
+            entry_map[key] = value
+            return True
+        else:
+            self._entry_order.append(key)
+            entry_map[key] = value
+            return False
+
+    def _delete_key(self, key):
+        entry_map = self._entry_map
+        if key in entry_map:
+            del entry_map[key]
+            self._entry_order.remove(key)
+            return True
+        else:
+            return False
+
+#=========================================================
+#htpasswd editing
+#=========================================================
+#FIXME: apr_md5_crypt technically the default only for windows, netware and tpf.
+#TODO: find out if htpasswd's "crypt" mode is crypt *call* or des_crypt implementation.
+htpasswd_context = CryptContext(["apr_md5_crypt", "des_crypt", "ldap_sha1", "plaintext" ])
+
+class HtpasswdFile(_CommonFile):
+    "class for reading & writing Htpasswd files"
+
+    def __init__(self, path, default=None, **kwds):
+        self.context = htpasswd_context
+        if default:
+            self.context = self.context.replace(default=default)
+        super(HtpasswdFile, self).__init__(path, **kwds)
+
+    def _parse_line(self, line):
+        #should be user, hash
+        return line.rstrip().split(":")
+
+    def _render_line(self, user, hash):
+        return "%s:%s\n" % (user, hash)
+
+    def update(self, user, password):
+        "update entry for user; added user if needed"
+        hash = self.context.encrypt(password)
+        return self._update_key(user, hash)
+
+    def delete(self, user):
+        "delete any entries for specified user"
+        return self._delete_key(user)
+
+    def verify(self, user, password):
+        "verify password for specified user"
+        hash = self._entry_map.get(user)
+        if hash is None:
+            return None
+        else:
+            return self.context.verify(password, hash)
+
+#=========================================================
+#htdigest editing
 #=========================================================
-postgres_context = CryptContext([postgres_md5])
+
+class HtdigestFile(_CommonFile):
+    "class for reading & writing Htdigest files"
+
+    def _parse_line(self, line):
+        user, realm, hash = line.rstrip().split(":")
+        return (user, realm), hash
+
+    def _render_line(self, key, hash):
+        return "%s:%s:%s\n" % (key[0], key[1], hash)
+
+    def update(self, user, realm, password):
+        "update entry for user+realm; added entry if needed"
+        key = (user,realm)
+        hash = md5("%s:%s:%s" % (user,realm,password)).hexdigest()
+        return self._update_key(key, hash)
+
+    def delete(self, user, realm):
+        "delete any entries for specified user+realm"
+        key = (user,realm)
+        return self._delete_key(key)
+
+    def delete_realm(self, realm):
+        "delete all entries for specified realm"
+        entry_order = self._entry_order
+        entry_map = self._entry_map
+        keys = [
+            key for key in entry_map
+            if key[1] == realm
+        ]
+        if keys:
+            for key in keys:
+                del entry_map[key]
+                entry_order.remove(key)
+            return True
+        else:
+            return False
+
+    def verify(self, user, realm, password):
+        "verify password for specified user+realm"
+        key = (user, realm)
+        hash = self._entry_map.get(key)
+        if hash is None:
+            return None
+        return hash == md5("%s:%s:%s" % (user,realm,password)).hexdigest()
 
 #=========================================================
 # eof
diff --git a/passlib/base.py b/passlib/base.py
index 76935bb..29fb45a 100644
--- a/passlib/base.py
+++ b/passlib/base.py
@@ -787,6 +787,9 @@ class CryptContext(object):
         names = [ handler.name for handler in self.policy.iter_handlers() ]
         return "<CryptContext %0xd schemes=%r>" % (id(self), names)
 
+    def replace(self, **kwds):
+        return CryptContext(policy=self.policy.replace(**kwds))
+
     #===================================================================
     #policy adaptation
     #===================================================================
diff --git a/passlib/drivers/ldap.py b/passlib/drivers/ldap.py
index f242567..886474a 100644
--- a/passlib/drivers/ldap.py
+++ b/passlib/drivers/ldap.py
@@ -90,7 +90,7 @@ class ldap_md5(_Base64DigestHelper):
     setting_kwds = ()
 
     _ident = "{MD5}"
-    _hash = hashlib.md5
+    _hash = md5
     _pat = re.compile(r"^\{MD5\}(?P<chk>[+/a-zA-Z0-9]{22}==)$")
 
 class ldap_sha1(_Base64DigestHelper):
@@ -98,20 +98,20 @@ class ldap_sha1(_Base64DigestHelper):
     setting_kwds = ()
 
     _ident = "{SHA}"
-    _hash = hashlib.sha1
+    _hash = sha1
     _pat = re.compile(r"^\{SHA\}(?P<chk>[+/a-zA-Z0-9]{27}=)$")
 
 class ldap_salted_md5(_SaltedBase64DigestHelper):
     name = "ldap_salted_md5"
     _ident = "{SMD5}"
-    _hash = hashlib.md5
+    _hash = md5
     _pat = re.compile(r"^\{SMD5\}(?P<tmp>[+/a-zA-Z0-9]{27}=)$")
     _default_chk = '\x00' * 16
 
 class ldap_salted_sha1(_SaltedBase64DigestHelper):
     name = "ldap_salted_sha1"
     _ident = "{SSHA}"
-    _hash = hashlib.sha1
+    _hash = sha1
     _pat = re.compile(r"^\{SSHA\}(?P<tmp>[+/a-zA-Z0-9]{32})$")
     _default_chk = '\x00' * 20