branchcache: add a "pure topological head" fast path
In a narrow but actually quick common case, all topological heads are all on
the same branch and all open. In this case, computing the branch map is very
simple. We can quickly detect situation where this situation will not change.
So we update the V3 format to be able to express this situation and upgrade the
update code to detect we remains in that mode.
The branch cache is populated with the actual value when the branch map is
accessed, but the update_disk method can do the update without needing to
populate it.
import base64
import hashlib
from mercurial.hgweb import common
from mercurial import node
def parse_keqv_list(req, l):
"""Parse list of key=value strings where keys are not duplicated."""
parsed = {}
for elt in l:
k, v = elt.split(b'=', 1)
if v[0:1] == b'"' and v[-1:] == b'"':
v = v[1:-1]
parsed[k] = v
return parsed
class digestauthserver:
def __init__(self):
self._user_hashes = {}
def gethashers(self):
def _md5sum(x):
m = hashlib.md5()
m.update(x)
return node.hex(m.digest())
h = _md5sum
kd = lambda s, d, h=h: h(b"%s:%s" % (s, d))
return h, kd
def adduser(self, user, password, realm):
h, kd = self.gethashers()
a1 = h(b'%s:%s:%s' % (user, realm, password))
self._user_hashes[(user, realm)] = a1
def makechallenge(self, realm):
# We aren't testing the protocol here, just that the bytes make the
# proper round trip. So hardcoded seems fine.
nonce = b'064af982c5b571cea6450d8eda91c20d'
return b'realm="%s", nonce="%s", algorithm=MD5, qop="auth"' % (
realm,
nonce,
)
def checkauth(self, req, header):
log = req.rawenv[b'wsgi.errors']
h, kd = self.gethashers()
resp = parse_keqv_list(req, header.split(b', '))
if resp.get(b'algorithm', b'MD5').upper() != b'MD5':
log.write(b'Unsupported algorithm: %s' % resp.get(b'algorithm'))
raise common.ErrorResponse(
common.HTTP_FORBIDDEN, b"unknown algorithm"
)
user = resp[b'username']
realm = resp[b'realm']
nonce = resp[b'nonce']
ha1 = self._user_hashes.get((user, realm))
if not ha1:
log.write(b'No hash found for user/realm "%s/%s"' % (user, realm))
raise common.ErrorResponse(common.HTTP_FORBIDDEN, b"bad user")
qop = resp.get(b'qop', b'auth')
if qop != b'auth':
log.write(b"Unsupported qop: %s" % qop)
raise common.ErrorResponse(common.HTTP_FORBIDDEN, b"bad qop")
cnonce, ncvalue = resp.get(b'cnonce'), resp.get(b'nc')
if not cnonce or not ncvalue:
log.write(b'No cnonce (%s) or ncvalue (%s)' % (cnonce, ncvalue))
raise common.ErrorResponse(common.HTTP_FORBIDDEN, b"no cnonce")
a2 = b'%s:%s' % (req.method, resp[b'uri'])
noncebit = b"%s:%s:%s:%s:%s" % (nonce, ncvalue, cnonce, qop, h(a2))
respdig = kd(ha1, noncebit)
if respdig != resp[b'response']:
log.write(
b'User/realm "%s/%s" gave %s, but expected %s'
% (user, realm, resp[b'response'], respdig)
)
return False
return True
digest = digestauthserver()
def perform_authentication(hgweb, req, op):
auth = req.headers.get(b'Authorization')
if req.headers.get(b'X-HgTest-AuthType') == b'Digest':
if not auth:
challenge = digest.makechallenge(b'mercurial')
raise common.ErrorResponse(
common.HTTP_UNAUTHORIZED,
b'who',
[(b'WWW-Authenticate', b'Digest %s' % challenge)],
)
if not digest.checkauth(req, auth[7:]):
raise common.ErrorResponse(common.HTTP_FORBIDDEN, b'no')
return
if not auth:
raise common.ErrorResponse(
common.HTTP_UNAUTHORIZED,
b'who',
[(b'WWW-Authenticate', b'Basic Realm="mercurial"')],
)
if base64.b64decode(auth.split()[1]).split(b':', 1) != [b'user', b'pass']:
raise common.ErrorResponse(common.HTTP_FORBIDDEN, b'no')
def extsetup(ui):
common.permhooks.insert(0, perform_authentication)
digest.adduser(b'user', b'pass', b'mercurial')