1 # hgweb/common.py - Utility functions needed by hgweb_mod and hgwebdir_mod

     2 #

     3 # Copyright 21 May 2005 - (c) 2005 Jake Edge <jake@edge2.net>

     4 # Copyright 2005, 2006 Matt Mackall <mpm@selenic.com>

     5 #

     6 # This software may be used and distributed according to the terms of the

     7 # GNU General Public License version 2 or any later version.

     8 

     9 import errno, mimetypes, os

    10 

    11 HTTP_OK = 200

    12 HTTP_NOT_MODIFIED = 304

    13 HTTP_BAD_REQUEST = 400

    14 HTTP_UNAUTHORIZED = 401

    15 HTTP_FORBIDDEN = 403

    16 HTTP_NOT_FOUND = 404

    17 HTTP_METHOD_NOT_ALLOWED = 405

    18 HTTP_SERVER_ERROR = 500

    19 

    20 # Hooks for hgweb permission checks; extensions can add hooks here. Each hook

    21 # is invoked like this: hook(hgweb, request, operation), where operation is

    22 # either read, pull or push. Hooks should either raise an ErrorResponse

    23 # exception, or just return.

    24 # It is possible to do both authentication and authorization through this.

    25 permhooks = []

    26 

    27 def checkauthz(hgweb, req, op):

    28     '''Check permission for operation based on request data (including

    29     authentication info). Return if op allowed, else raise an ErrorResponse

    30     exception.'''

    31 

    32     user = req.env.get('REMOTE_USER')

    33 

    34     deny_read = hgweb.configlist('web', 'deny_read')

    35     if deny_read and (not user or deny_read == ['*'] or user in deny_read):

    36         raise ErrorResponse(HTTP_UNAUTHORIZED, 'read not authorized')

    37 

    38     allow_read = hgweb.configlist('web', 'allow_read')

    39     result = (not allow_read) or (allow_read == ['*'])

    40     if not (result or user in allow_read):

    41         raise ErrorResponse(HTTP_UNAUTHORIZED, 'read not authorized')

    42 

    43     if op == 'pull' and not hgweb.allowpull:

    44         raise ErrorResponse(HTTP_UNAUTHORIZED, 'pull not authorized')

    45     elif op == 'pull' or op is None: # op is None for interface requests

    46         return

    47 

    48     # enforce that you can only push using POST requests

    49     if req.env['REQUEST_METHOD'] != 'POST':

    50         msg = 'push requires POST request'

    51         raise ErrorResponse(HTTP_METHOD_NOT_ALLOWED, msg)

    52 

    53     # require ssl by default for pushing, auth info cannot be sniffed

    54     # and replayed

    55     scheme = req.env.get('wsgi.url_scheme')

    56     if hgweb.configbool('web', 'push_ssl', True) and scheme != 'https':

    57         raise ErrorResponse(HTTP_OK, 'ssl required')

    58 

    59     deny = hgweb.configlist('web', 'deny_push')

    60     if deny and (not user or deny == ['*'] or user in deny):

    61         raise ErrorResponse(HTTP_UNAUTHORIZED, 'push not authorized')

    62 

    63     allow = hgweb.configlist('web', 'allow_push')

    64     result = allow and (allow == ['*'] or user in allow)

    65     if not result:

    66         raise ErrorResponse(HTTP_UNAUTHORIZED, 'push not authorized')

    67 

    68 # Add the default permhook, which provides simple authorization.

    69 permhooks.append(checkauthz)

    70 

    71 

    72 class ErrorResponse(Exception):

    73     def __init__(self, code, message=None, headers=[]):

    74         Exception.__init__(self)

    75         self.code = code

    76         self.headers = headers

    77         if message is not None:

    78             self.message = message

    79         else:

    80             self.message = _statusmessage(code)

    81 

    82 def _statusmessage(code):

    83     from BaseHTTPServer import BaseHTTPRequestHandler

    84     responses = BaseHTTPRequestHandler.responses

    85     return responses.get(code, ('Error', 'Unknown error'))[0]

    86 

    87 def statusmessage(code, message=None):

    88     return '%d %s' % (code, message or _statusmessage(code))

    89 

    90 def get_mtime(spath):

    91     cl_path = os.path.join(spath, "00changelog.i")

    92     if os.path.exists(cl_path):

    93         return os.stat(cl_path).st_mtime

    94     else:

    95         return os.stat(spath).st_mtime

    96 

    97 def staticfile(directory, fname, req):

    98     """return a file inside directory with guessed Content-Type header

    99 

   100     fname always uses '/' as directory separator and isn't allowed to

   101     contain unusual path components.

   102     Content-Type is guessed using the mimetypes module.

   103     Return an empty string if fname is illegal or file not found.

   104 

   105     """

   106     parts = fname.split('/')

   107     for part in parts:

   108         if (part in ('', os.curdir, os.pardir) or

   109             os.sep in part or os.altsep is not None and os.altsep in part):

   110             return ""

   111     fpath = os.path.join(*parts)

   112     if isinstance(directory, str):

   113         directory = [directory]

   114     for d in directory:

   115         path = os.path.join(d, fpath)

   116         if os.path.exists(path):

   117             break

   118     try:

   119         os.stat(path)

   120         ct = mimetypes.guess_type(path)[0] or "text/plain"

   121         req.respond(HTTP_OK, ct, length = os.path.getsize(path))

   122         return open(path, 'rb').read()

   123     except TypeError:

   124         raise ErrorResponse(HTTP_SERVER_ERROR, 'illegal filename')

   125     except OSError, err:

   126         if err.errno == errno.ENOENT:

   127             raise ErrorResponse(HTTP_NOT_FOUND)

   128         else:

   129             raise ErrorResponse(HTTP_SERVER_ERROR, err.strerror)

   130 

   131 def paritygen(stripecount, offset=0):

   132     """count parity of horizontal stripes for easier reading"""

   133     if stripecount and offset:

   134         # account for offset, e.g. due to building the list in reverse

   135         count = (stripecount + offset) % stripecount

   136         parity = (stripecount + offset) / stripecount & 1

   137     else:

   138         count = 0

   139         parity = 0

   140     while True:

   141         yield parity

   142         count += 1

   143         if stripecount and count >= stripecount:

   144             parity = 1 - parity

   145             count = 0

   146 

   147 def get_contact(config):

   148     """Return repo contact information or empty string.

   149 

   150     web.contact is the primary source, but if that is not set, try

   151     ui.username or $EMAIL as a fallback to display something useful.

   152     """

   153     return (config("web", "contact") or

   154             config("ui", "username") or

   155             os.environ.get("EMAIL") or "")

   156 

   157 def caching(web, req):

   158     tag = str(web.mtime)

   159     if req.env.get('HTTP_IF_NONE_MATCH') == tag:

   160         raise ErrorResponse(HTTP_NOT_MODIFIED)

   161     req.headers.append(('ETag', tag))