675 lines
24 KiB
Python
675 lines
24 KiB
Python
# Copyright 2010 United States Government as represented by the
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# Administrator of the National Aeronautics and Space Administration.
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# Copyright 2014 SoftLayer Technologies, Inc.
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# Copyright 2015 Mirantis, Inc
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# All Rights Reserved.
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#
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# Licensed under the Apache License, Version 2.0 (the "License"); you may
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# not use this file except in compliance with the License. You may obtain
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# a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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# License for the specific language governing permissions and limitations
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# under the License.
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"""
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System-level utilities and helper functions.
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"""
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import errno
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try:
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from eventlet import sleep
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except ImportError:
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from time import sleep
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from eventlet.green import socket
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import functools
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import os
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import re
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import uuid
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from OpenSSL import crypto
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from oslo_config import cfg
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from oslo_log import log as logging
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from oslo_utils import encodeutils
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from oslo_utils import excutils
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from oslo_utils import netutils
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from oslo_utils import strutils
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import six
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from webob import exc
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from glance.common import exception
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from glance.common import timeutils
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from glance.i18n import _, _LE, _LW
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CONF = cfg.CONF
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LOG = logging.getLogger(__name__)
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# Whitelist of v1 API headers of form x-image-meta-xxx
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IMAGE_META_HEADERS = ['x-image-meta-location', 'x-image-meta-size',
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'x-image-meta-is_public', 'x-image-meta-disk_format',
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'x-image-meta-container_format', 'x-image-meta-name',
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'x-image-meta-status', 'x-image-meta-copy_from',
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'x-image-meta-uri', 'x-image-meta-checksum',
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'x-image-meta-created_at', 'x-image-meta-updated_at',
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'x-image-meta-deleted_at', 'x-image-meta-min_ram',
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'x-image-meta-min_disk', 'x-image-meta-owner',
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'x-image-meta-store', 'x-image-meta-id',
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'x-image-meta-protected', 'x-image-meta-deleted',
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'x-image-meta-virtual_size']
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GLANCE_TEST_SOCKET_FD_STR = 'GLANCE_TEST_SOCKET_FD'
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def chunkreadable(iter, chunk_size=65536):
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"""
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Wrap a readable iterator with a reader yielding chunks of
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a preferred size, otherwise leave iterator unchanged.
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:param iter: an iter which may also be readable
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:param chunk_size: maximum size of chunk
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"""
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return chunkiter(iter, chunk_size) if hasattr(iter, 'read') else iter
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def chunkiter(fp, chunk_size=65536):
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"""
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Return an iterator to a file-like obj which yields fixed size chunks
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:param fp: a file-like object
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:param chunk_size: maximum size of chunk
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"""
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while True:
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chunk = fp.read(chunk_size)
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if chunk:
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yield chunk
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else:
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break
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def cooperative_iter(iter):
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"""
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Return an iterator which schedules after each
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iteration. This can prevent eventlet thread starvation.
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:param iter: an iterator to wrap
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"""
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try:
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for chunk in iter:
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sleep(0)
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yield chunk
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except Exception as err:
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with excutils.save_and_reraise_exception():
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msg = _LE("Error: cooperative_iter exception %s") % err
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LOG.error(msg)
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def cooperative_read(fd):
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"""
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Wrap a file descriptor's read with a partial function which schedules
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after each read. This can prevent eventlet thread starvation.
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:param fd: a file descriptor to wrap
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"""
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def readfn(*args):
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result = fd.read(*args)
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sleep(0)
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return result
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return readfn
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MAX_COOP_READER_BUFFER_SIZE = 134217728 # 128M seems like a sane buffer limit
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class CooperativeReader(object):
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"""
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An eventlet thread friendly class for reading in image data.
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When accessing data either through the iterator or the read method
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we perform a sleep to allow a co-operative yield. When there is more than
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one image being uploaded/downloaded this prevents eventlet thread
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starvation, ie allows all threads to be scheduled periodically rather than
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having the same thread be continuously active.
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"""
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def __init__(self, fd):
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"""
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:param fd: Underlying image file object
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"""
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self.fd = fd
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self.iterator = None
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# NOTE(markwash): if the underlying supports read(), overwrite the
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# default iterator-based implementation with cooperative_read which
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# is more straightforward
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if hasattr(fd, 'read'):
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self.read = cooperative_read(fd)
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else:
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self.iterator = None
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self.buffer = b''
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self.position = 0
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def read(self, length=None):
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"""Return the requested amount of bytes, fetching the next chunk of
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the underlying iterator when needed.
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This is replaced with cooperative_read in __init__ if the underlying
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fd already supports read().
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"""
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if length is None:
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if len(self.buffer) - self.position > 0:
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# if no length specified but some data exists in buffer,
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# return that data and clear the buffer
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result = self.buffer[self.position:]
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self.buffer = b''
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self.position = 0
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return str(result)
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else:
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# otherwise read the next chunk from the underlying iterator
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# and return it as a whole. Reset the buffer, as subsequent
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# calls may specify the length
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try:
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if self.iterator is None:
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self.iterator = self.__iter__()
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return next(self.iterator)
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except StopIteration:
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return ''
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finally:
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self.buffer = b''
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self.position = 0
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else:
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result = bytearray()
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while len(result) < length:
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if self.position < len(self.buffer):
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to_read = length - len(result)
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chunk = self.buffer[self.position:self.position + to_read]
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result.extend(chunk)
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# This check is here to prevent potential OOM issues if
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# this code is called with unreasonably high values of read
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# size. Currently it is only called from the HTTP clients
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# of Glance backend stores, which use httplib for data
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# streaming, which has readsize hardcoded to 8K, so this
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# check should never fire. Regardless it still worths to
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# make the check, as the code may be reused somewhere else.
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if len(result) >= MAX_COOP_READER_BUFFER_SIZE:
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raise exception.LimitExceeded()
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self.position += len(chunk)
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else:
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try:
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if self.iterator is None:
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self.iterator = self.__iter__()
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self.buffer = next(self.iterator)
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self.position = 0
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except StopIteration:
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self.buffer = b''
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self.position = 0
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return bytes(result)
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return bytes(result)
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def __iter__(self):
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return cooperative_iter(self.fd.__iter__())
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class LimitingReader(object):
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"""
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Reader designed to fail when reading image data past the configured
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allowable amount.
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"""
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def __init__(self, data, limit):
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"""
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:param data: Underlying image data object
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:param limit: maximum number of bytes the reader should allow
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"""
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self.data = data
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self.limit = limit
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self.bytes_read = 0
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def __iter__(self):
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for chunk in self.data:
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self.bytes_read += len(chunk)
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if self.bytes_read > self.limit:
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raise exception.ImageSizeLimitExceeded()
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else:
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yield chunk
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def read(self, i):
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result = self.data.read(i)
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self.bytes_read += len(result)
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if self.bytes_read > self.limit:
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raise exception.ImageSizeLimitExceeded()
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return result
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def image_meta_to_http_headers(image_meta):
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"""
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Returns a set of image metadata into a dict
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of HTTP headers that can be fed to either a Webob
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Request object or an httplib.HTTP(S)Connection object
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:param image_meta: Mapping of image metadata
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"""
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headers = {}
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for k, v in image_meta.items():
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if v is not None:
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if k == 'properties':
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for pk, pv in v.items():
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if pv is not None:
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headers["x-image-meta-property-%s"
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% pk.lower()] = six.text_type(pv)
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else:
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headers["x-image-meta-%s" % k.lower()] = six.text_type(v)
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return headers
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def get_image_meta_from_headers(response):
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"""
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Processes HTTP headers from a supplied response that
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match the x-image-meta and x-image-meta-property and
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returns a mapping of image metadata and properties
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:param response: Response to process
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"""
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result = {}
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properties = {}
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if hasattr(response, 'getheaders'): # httplib.HTTPResponse
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headers = response.getheaders()
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else: # webob.Response
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headers = response.headers.items()
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for key, value in headers:
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key = str(key.lower())
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if key.startswith('x-image-meta-property-'):
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field_name = key[len('x-image-meta-property-'):].replace('-', '_')
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properties[field_name] = value or None
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elif key.startswith('x-image-meta-'):
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field_name = key[len('x-image-meta-'):].replace('-', '_')
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if 'x-image-meta-' + field_name not in IMAGE_META_HEADERS:
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msg = _("Bad header: %(header_name)s") % {'header_name': key}
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raise exc.HTTPBadRequest(msg, content_type="text/plain")
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result[field_name] = value or None
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result['properties'] = properties
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for key, nullable in [('size', False), ('min_disk', False),
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('min_ram', False), ('virtual_size', True)]:
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if key in result:
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try:
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result[key] = int(result[key])
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except ValueError:
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if nullable and result[key] == str(None):
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result[key] = None
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else:
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extra = (_("Cannot convert image %(key)s '%(value)s' "
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"to an integer.")
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% {'key': key, 'value': result[key]})
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raise exception.InvalidParameterValue(value=result[key],
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param=key,
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extra_msg=extra)
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if result[key] is not None and result[key] < 0:
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extra = _('Cannot be a negative value.')
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raise exception.InvalidParameterValue(value=result[key],
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param=key,
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extra_msg=extra)
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for key in ('is_public', 'deleted', 'protected'):
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if key in result:
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result[key] = strutils.bool_from_string(result[key])
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return result
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def create_mashup_dict(image_meta):
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"""
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Returns a dictionary-like mashup of the image core properties
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and the image custom properties from given image metadata.
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:param image_meta: metadata of image with core and custom properties
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"""
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d = {}
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for key, value in six.iteritems(image_meta):
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if isinstance(value, dict):
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for subkey, subvalue in six.iteritems(
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create_mashup_dict(value)):
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if subkey not in image_meta:
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d[subkey] = subvalue
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else:
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d[key] = value
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return d
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def safe_mkdirs(path):
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try:
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os.makedirs(path)
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except OSError as e:
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if e.errno != errno.EEXIST:
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raise
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def mutating(func):
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"""Decorator to enforce read-only logic"""
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@functools.wraps(func)
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def wrapped(self, req, *args, **kwargs):
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if req.context.read_only:
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msg = "Read-only access"
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LOG.debug(msg)
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raise exc.HTTPForbidden(msg, request=req,
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content_type="text/plain")
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return func(self, req, *args, **kwargs)
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return wrapped
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def setup_remote_pydev_debug(host, port):
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error_msg = _LE('Error setting up the debug environment. Verify that the'
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' option pydev_worker_debug_host is pointing to a valid '
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'hostname or IP on which a pydev server is listening on'
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' the port indicated by pydev_worker_debug_port.')
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try:
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try:
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from pydev import pydevd
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except ImportError:
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import pydevd
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pydevd.settrace(host,
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port=port,
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stdoutToServer=True,
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stderrToServer=True)
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return True
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except Exception:
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with excutils.save_and_reraise_exception():
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LOG.exception(error_msg)
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def validate_key_cert(key_file, cert_file):
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try:
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error_key_name = "private key"
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error_filename = key_file
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with open(key_file, 'r') as keyfile:
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key_str = keyfile.read()
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key = crypto.load_privatekey(crypto.FILETYPE_PEM, key_str)
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error_key_name = "certificate"
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error_filename = cert_file
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with open(cert_file, 'r') as certfile:
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cert_str = certfile.read()
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cert = crypto.load_certificate(crypto.FILETYPE_PEM, cert_str)
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except IOError as ioe:
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raise RuntimeError(_("There is a problem with your %(error_key_name)s "
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"%(error_filename)s. Please verify it."
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" Error: %(ioe)s") %
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{'error_key_name': error_key_name,
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'error_filename': error_filename,
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'ioe': ioe})
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except crypto.Error as ce:
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raise RuntimeError(_("There is a problem with your %(error_key_name)s "
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"%(error_filename)s. Please verify it. OpenSSL"
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" error: %(ce)s") %
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{'error_key_name': error_key_name,
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'error_filename': error_filename,
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'ce': ce})
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try:
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data = str(uuid.uuid4())
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# On Python 3, explicitly encode to UTF-8 to call crypto.sign() which
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# requires bytes. Otherwise, it raises a deprecation warning (and
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# will raise an error later).
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data = encodeutils.to_utf8(data)
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digest = CONF.digest_algorithm
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if digest == 'sha1':
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LOG.warn(
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_LW('The FIPS (FEDERAL INFORMATION PROCESSING STANDARDS)'
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' state that the SHA-1 is not suitable for'
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' general-purpose digital signature applications (as'
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' specified in FIPS 186-3) that require 112 bits of'
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' security. The default value is sha1 in Kilo for a'
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' smooth upgrade process, and it will be updated'
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' with sha256 in next release(L).'))
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out = crypto.sign(key, data, digest)
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crypto.verify(cert, out, data, digest)
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except crypto.Error as ce:
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raise RuntimeError(_("There is a problem with your key pair. "
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"Please verify that cert %(cert_file)s and "
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"key %(key_file)s belong together. OpenSSL "
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"error %(ce)s") % {'cert_file': cert_file,
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'key_file': key_file,
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'ce': ce})
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def get_test_suite_socket():
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global GLANCE_TEST_SOCKET_FD_STR
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if GLANCE_TEST_SOCKET_FD_STR in os.environ:
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fd = int(os.environ[GLANCE_TEST_SOCKET_FD_STR])
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sock = socket.fromfd(fd, socket.AF_INET, socket.SOCK_STREAM)
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if six.PY2:
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sock = socket.SocketType(_sock=sock)
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sock.listen(CONF.backlog)
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del os.environ[GLANCE_TEST_SOCKET_FD_STR]
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os.close(fd)
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return sock
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return None
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def is_valid_hostname(hostname):
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"""Verify whether a hostname (not an FQDN) is valid."""
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return re.match('^[a-zA-Z0-9-]+$', hostname) is not None
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def is_valid_fqdn(fqdn):
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"""Verify whether a host is a valid FQDN."""
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return re.match('^[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$', fqdn) is not None
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def parse_valid_host_port(host_port):
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"""
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Given a "host:port" string, attempts to parse it as intelligently as
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possible to determine if it is valid. This includes IPv6 [host]:port form,
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IPv4 ip:port form, and hostname:port or fqdn:port form.
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Invalid inputs will raise a ValueError, while valid inputs will return
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a (host, port) tuple where the port will always be of type int.
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"""
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try:
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try:
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host, port = netutils.parse_host_port(host_port)
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except Exception:
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raise ValueError(_('Host and port "%s" is not valid.') % host_port)
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if not netutils.is_valid_port(port):
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raise ValueError(_('Port "%s" is not valid.') % port)
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# First check for valid IPv6 and IPv4 addresses, then a generic
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# hostname. Failing those, if the host includes a period, then this
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# should pass a very generic FQDN check. The FQDN check for letters at
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# the tail end will weed out any hilariously absurd IPv4 addresses.
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if not (netutils.is_valid_ipv6(host) or netutils.is_valid_ipv4(host) or
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is_valid_hostname(host) or is_valid_fqdn(host)):
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raise ValueError(_('Host "%s" is not valid.') % host)
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except Exception as ex:
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raise ValueError(_('%s '
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'Please specify a host:port pair, where host is an '
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'IPv4 address, IPv6 address, hostname, or FQDN. If '
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'using an IPv6 address, enclose it in brackets '
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'separately from the port (i.e., '
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'"[fe80::a:b:c]:9876").') % ex)
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return (host, int(port))
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try:
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REGEX_4BYTE_UNICODE = re.compile(u'[\U00010000-\U0010ffff]')
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except re.error:
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# UCS-2 build case
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REGEX_4BYTE_UNICODE = re.compile(u'[\uD800-\uDBFF][\uDC00-\uDFFF]')
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def no_4byte_params(f):
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"""
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Checks that no 4 byte unicode characters are allowed
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in dicts' keys/values and string's parameters
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"""
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def wrapper(*args, **kwargs):
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def _is_match(some_str):
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|
return (isinstance(some_str, six.text_type) and
|
|
REGEX_4BYTE_UNICODE.findall(some_str) != [])
|
|
|
|
def _check_dict(data_dict):
|
|
# a dict of dicts has to be checked recursively
|
|
for key, value in six.iteritems(data_dict):
|
|
if isinstance(value, dict):
|
|
_check_dict(value)
|
|
else:
|
|
if _is_match(key):
|
|
msg = _("Property names can't contain 4 byte unicode.")
|
|
raise exception.Invalid(msg)
|
|
if _is_match(value):
|
|
msg = (_("%s can't contain 4 byte unicode characters.")
|
|
% key.title())
|
|
raise exception.Invalid(msg)
|
|
|
|
for data_dict in [arg for arg in args if isinstance(arg, dict)]:
|
|
_check_dict(data_dict)
|
|
# now check args for str values
|
|
for arg in args:
|
|
if _is_match(arg):
|
|
msg = _("Param values can't contain 4 byte unicode.")
|
|
raise exception.Invalid(msg)
|
|
# check kwargs as well, as params are passed as kwargs via
|
|
# registry calls
|
|
_check_dict(kwargs)
|
|
return f(*args, **kwargs)
|
|
return wrapper
|
|
|
|
|
|
def stash_conf_values():
|
|
"""
|
|
Make a copy of some of the current global CONF's settings.
|
|
Allows determining if any of these values have changed
|
|
when the config is reloaded.
|
|
"""
|
|
conf = {
|
|
'bind_host': CONF.bind_host,
|
|
'bind_port': CONF.bind_port,
|
|
'tcp_keepidle': CONF.cert_file,
|
|
'backlog': CONF.backlog,
|
|
'key_file': CONF.key_file,
|
|
'cert_file': CONF.cert_file
|
|
}
|
|
|
|
return conf
|
|
|
|
|
|
def split_filter_op(expression):
|
|
"""Split operator from threshold in an expression.
|
|
Designed for use on a comparative-filtering query field.
|
|
When no operator is found, default to an equality comparison.
|
|
|
|
:param expression: the expression to parse
|
|
|
|
:returns: a tuple (operator, threshold) parsed from expression
|
|
"""
|
|
left, sep, right = expression.partition(':')
|
|
if sep:
|
|
# If the expression is a date of the format ISO 8601 like
|
|
# CCYY-MM-DDThh:mm:ss+hh:mm and has no operator, it should
|
|
# not be partitioned, and a default operator of eq should be
|
|
# assumed.
|
|
try:
|
|
timeutils.parse_isotime(expression)
|
|
op = 'eq'
|
|
threshold = expression
|
|
except ValueError:
|
|
op = left
|
|
threshold = right
|
|
else:
|
|
op = 'eq' # default operator
|
|
threshold = left
|
|
|
|
# NOTE stevelle decoding escaped values may be needed later
|
|
return op, threshold
|
|
|
|
|
|
def validate_quotes(value):
|
|
"""Validate filter values
|
|
|
|
Validation opening/closing quotes in the expression.
|
|
"""
|
|
open_quotes = True
|
|
for i in range(len(value)):
|
|
if value[i] == '"':
|
|
if i and value[i - 1] == '\\':
|
|
continue
|
|
if open_quotes:
|
|
if i and value[i - 1] != ',':
|
|
msg = _("Invalid filter value %s. There is no comma "
|
|
"before opening quotation mark.") % value
|
|
raise exception.InvalidParameterValue(message=msg)
|
|
else:
|
|
if i + 1 != len(value) and value[i + 1] != ",":
|
|
msg = _("Invalid filter value %s. There is no comma "
|
|
"after closing quotation mark.") % value
|
|
raise exception.InvalidParameterValue(message=msg)
|
|
open_quotes = not open_quotes
|
|
if not open_quotes:
|
|
msg = _("Invalid filter value %s. The quote is not closed.") % value
|
|
raise exception.InvalidParameterValue(message=msg)
|
|
|
|
|
|
def split_filter_value_for_quotes(value):
|
|
"""Split filter values
|
|
|
|
Split values by commas and quotes for 'in' operator, according api-wg.
|
|
"""
|
|
validate_quotes(value)
|
|
tmp = re.compile(r'''
|
|
"( # if found a double-quote
|
|
[^\"\\]* # take characters either non-quotes or backslashes
|
|
(?:\\. # take backslashes and character after it
|
|
[^\"\\]*)* # take characters either non-quotes or backslashes
|
|
) # before double-quote
|
|
",? # a double-quote with comma maybe
|
|
| ([^,]+),? # if not found double-quote take any non-comma
|
|
# characters with comma maybe
|
|
| , # if we have only comma take empty string
|
|
''', re.VERBOSE)
|
|
return [val[0] or val[1] for val in re.findall(tmp, value)]
|
|
|
|
|
|
def evaluate_filter_op(value, operator, threshold):
|
|
"""Evaluate a comparison operator.
|
|
Designed for use on a comparative-filtering query field.
|
|
|
|
:param value: evaluated against the operator, as left side of expression
|
|
:param operator: any supported filter operation
|
|
:param threshold: to compare value against, as right side of expression
|
|
|
|
:raises: InvalidFilterOperatorValue if an unknown operator is provided
|
|
|
|
:returns: boolean result of applied comparison
|
|
|
|
"""
|
|
if operator == 'gt':
|
|
return value > threshold
|
|
elif operator == 'gte':
|
|
return value >= threshold
|
|
elif operator == 'lt':
|
|
return value < threshold
|
|
elif operator == 'lte':
|
|
return value <= threshold
|
|
elif operator == 'neq':
|
|
return value != threshold
|
|
elif operator == 'eq':
|
|
return value == threshold
|
|
|
|
msg = _("Unable to filter on a unknown operator.")
|
|
raise exception.InvalidFilterOperatorValue(msg)
|