def get_acl(self, headers, body, bucket_owner, object_owner=None):
"""
Get ACL instance from S3 (e.g. x-amz-grant) headers or S3 acl xml body.
"""
acl = ACL.from_headers(headers,
bucket_owner,
object_owner,
as_private=False)
if acl is None:
# Get acl from request body if possible.
if not body:
raise MissingSecurityHeader(missing_header_name='x-amz-acl')
try:
elem = fromstring(body, ACL.root_tag)
acl = ACL.from_elem(elem, True, self.req.allow_no_owner)
except (XMLSyntaxError, DocumentInvalid):
raise MalformedACLError()
except Exception as e:
exc_type, exc_value, exc_traceback = sys.exc_info()
self.logger.error(e)
raise exc_type, exc_value, exc_traceback
else:
if body:
# Specifying grant with both header and xml is not allowed.
raise UnexpectedContent()
return acl
def PUT(self, req):
"""
Handles PUT Bucket acl and PUT Object acl.
"""
if req.is_object_request:
# Handle Object ACL
raise S3NotImplemented()
else:
# Handle Bucket ACL
xml = req.xml(MAX_ACL_BODY_SIZE)
if all(['HTTP_X_AMZ_ACL' in req.environ, xml]):
# S3 doesn't allow to give ACL with both ACL header and body.
raise UnexpectedContent()
elif not any(['HTTP_X_AMZ_ACL' in req.environ, xml]):
# Both canned ACL header and xml body are missing
raise MissingSecurityHeader(missing_header_name='x-amz-acl')
else:
# correct ACL exists in the request
if xml:
# We very likely have an XML-based ACL request.
# let's try to translate to the request header
try:
translated_acl = swift_acl_translate(xml, xml=True)
except ACLError:
raise MalformedACLError()
for header, acl in translated_acl:
req.headers[header] = acl
resp = req.get_response(self.app, 'POST')
resp.status = HTTP_OK
resp.headers.update({'Location': req.container_name})
return resp
def from_elem(elem):
type = elem.get('{%s}type' % XMLNS_XSI)
if type == 'CanonicalUser':
value = elem.find('./ID').text
return User(value)
elif type == 'Group':
value = elem.find('./URI').text
subclass = get_group_subclass_from_uri(value)
return subclass()
elif type == 'AmazonCustomerByEmail':
raise S3NotImplemented()
else:
raise MalformedACLError()
def swift_acl_translate(acl, group='', user='', xml=False):
"""
Takes an S3 style ACL and returns a list of header/value pairs that
implement that ACL in Swift, or "NotImplemented" if there isn't a way to do
that yet.
"""
swift_acl = {}
swift_acl['public-read'] = [['X-Container-Read', '.r:*,.rlistings']]
# Swift does not support public write:
# https://answers.launchpad.net/swift/+question/169541
swift_acl['public-read-write'] = [['X-Container-Write', '.r:*'],
['X-Container-Read', '.r:*,.rlistings']]
# TODO: if there's a way to get group and user, this should work for
# private:
# swift_acl['private'] = \
# [['HTTP_X_CONTAINER_WRITE', group + ':' + user], \
# ['HTTP_X_CONTAINER_READ', group + ':' + user]]
swift_acl['private'] = [['X-Container-Write', '.'],
['X-Container-Read', '.']]
if xml:
# We are working with XML and need to parse it
try:
elem = fromstring(acl, 'AccessControlPolicy')
except (XMLSyntaxError, DocumentInvalid):
raise MalformedACLError()
acl = 'unknown'
for grant in elem.findall('./AccessControlList/Grant'):
permission = grant.find('./Permission').text
grantee = grant.find('./Grantee').get('{%s}type' % XMLNS_XSI)
if permission == "FULL_CONTROL" and grantee == 'CanonicalUser' and\
acl != 'public-read' and acl != 'public-read-write':
acl = 'private'
elif permission == "READ" and grantee == 'Group' and\
acl != 'public-read-write':
acl = 'public-read'
elif permission == "WRITE" and grantee == 'Group':
acl = 'public-read-write'
else:
acl = 'unsupported'
if acl == 'authenticated-read':
raise S3NotImplemented()
elif acl not in swift_acl:
raise ACLError()
return swift_acl[acl]