def _validate_and_prep_request_headers(req):
"""
Validate that the value from x-symlink-target header is well formatted
and that the x-symlink-target-etag header (if present) does not contain
problematic characters. We assume the caller ensures that
x-symlink-target header is present in req.headers.
:param req: HTTP request object
:returns: a tuple, the full versioned path to the object (as a WSGI string)
and the X-Symlink-Target-Etag header value which may be None
:raise: HTTPPreconditionFailed if x-symlink-target value
is not well formatted.
:raise: HTTPBadRequest if the x-symlink-target value points to the request
path.
:raise: HTTPBadRequest if the x-symlink-target-etag value contains
a semicolon, double-quote, or backslash.
"""
# N.B. check_path_header doesn't assert the leading slash and
# copy middleware may accept the format. In the symlink, API
# says apparently to use "container/object" format so add the
# validation first, here.
error_body = 'X-Symlink-Target header must be of the form ' \
'<container name>/<object name>'
if wsgi_unquote(req.headers[TGT_OBJ_SYMLINK_HDR]).startswith('/'):
raise HTTPPreconditionFailed(body=error_body,
request=req,
content_type='text/plain')
# check container and object format
container, obj = check_path_header(req, TGT_OBJ_SYMLINK_HDR, 2, error_body)
req.headers[TGT_OBJ_SYMLINK_HDR] = wsgi_quote('%s/%s' % (container, obj))
# Check account format if it exists
account = check_account_format(
req, wsgi_unquote(req.headers[TGT_ACCT_SYMLINK_HDR])) \
if TGT_ACCT_SYMLINK_HDR in req.headers else None
# Extract request path
_junk, req_acc, req_cont, req_obj = req.split_path(4, 4, True)
if account:
req.headers[TGT_ACCT_SYMLINK_HDR] = wsgi_quote(account)
else:
account = req_acc
# Check if symlink targets the symlink itself or not
if (account, container, obj) == (req_acc, req_cont, req_obj):
raise HTTPBadRequest(body='Symlink cannot target itself',
request=req,
content_type='text/plain')
etag = req.headers.get(TGT_ETAG_SYMLINK_HDR, None)
if etag and any(c in etag for c in ';"\\'):
# See cgi.parse_header for why the above chars are problematic
raise HTTPBadRequest(body='Bad %s format' %
TGT_ETAG_SYMLINK_HDR.title(),
request=req,
content_type='text/plain')
if not (etag or req.headers.get('Content-Type')):
req.headers['Content-Type'] = 'application/symlink'
return '/v1/%s/%s/%s' % (account, container, obj), etag
def _check_symlink_header(req):
"""
Validate that the value from x-symlink-target header is
well formatted. We assume the caller ensures that
x-symlink-target header is present in req.headers.
:param req: HTTP request object
:raise: HTTPPreconditionFailed if x-symlink-target value
is not well formatted.
:raise: HTTPBadRequest if the x-symlink-target value points to the request
path.
"""
# N.B. check_path_header doesn't assert the leading slash and
# copy middleware may accept the format. In the symlink, API
# says apparently to use "container/object" format so add the
# validation first, here.
error_body = 'X-Symlink-Target header must be of the form ' \
'<container name>/<object name>'
try:
if wsgi_unquote(req.headers[TGT_OBJ_SYMLINK_HDR]).startswith('/'):
raise HTTPPreconditionFailed(body=error_body,
request=req,
content_type='text/plain')
except TypeError:
raise HTTPPreconditionFailed(body=error_body,
request=req,
content_type='text/plain')
# check container and object format
container, obj = check_path_header(req, TGT_OBJ_SYMLINK_HDR, 2, error_body)
req.headers[TGT_OBJ_SYMLINK_HDR] = wsgi_quote('%s/%s' % (container, obj))
# Check account format if it exists
try:
account = check_account_format(
req, wsgi_unquote(req.headers[TGT_ACCT_SYMLINK_HDR])) \
if TGT_ACCT_SYMLINK_HDR in req.headers else None
except TypeError:
raise HTTPPreconditionFailed(
body='Account name cannot contain slashes',
request=req,
content_type='text/plain')
# Extract request path
_junk, req_acc, req_cont, req_obj = req.split_path(4, 4, True)
if account:
req.headers[TGT_ACCT_SYMLINK_HDR] = wsgi_quote(account)
else:
account = req_acc
# Check if symlink targets the symlink itself or not
if (account, container, obj) == (req_acc, req_cont, req_obj):
raise HTTPBadRequest(body='Symlink cannot target itself',
request=req,
content_type='text/plain')
def _check_destination_header(req):
"""
Validate that the value from destination header is
well formatted. We assume the caller ensures that
destination header is present in req.headers.
:param req: HTTP request object
:returns: A tuple with container name and object name
:raise HTTPPreconditionFailed: if destination value
is not well formatted.
"""
return check_path_header(
req, 'Destination', 2, 'Destination header must be of the form '
'<container name>/<object name>')
def _check_destination_header(req):
"""
Validate that the value from destination header is
well formatted. We assume the caller ensures that
destination header is present in req.headers.
:param req: HTTP request object
:returns: A tuple with container name and object name
:raise HTTPPreconditionFailed: if destination value
is not well formatted.
"""
return check_path_header(req, 'Destination', 2,
'Destination header must be of the form '
'<container name>/<object name>')
def _check_symlink_header(req):
"""
Validate that the value from x-symlink-target header is
well formatted. We assume the caller ensures that
x-symlink-target header is present in req.headers.
:param req: HTTP request object
:raise: HTTPPreconditionFailed if x-symlink-target value
is not well formatted.
:raise: HTTPBadRequest if the x-symlink-target value points to the request
path.
"""
# N.B. check_path_header doesn't assert the leading slash and
# copy middleware may accept the format. In the symlink, API
# says apparently to use "container/object" format so add the
# validation first, here.
if unquote(req.headers[TGT_OBJ_SYMLINK_HDR]).startswith('/'):
raise HTTPPreconditionFailed(
body='X-Symlink-Target header must be of the '
'form <container name>/<object name>',
request=req, content_type='text/plain')
# check container and object format
container, obj = check_path_header(
req, TGT_OBJ_SYMLINK_HDR, 2,
'X-Symlink-Target header must be of the '
'form <container name>/<object name>')
# Check account format if it exists
account = check_account_format(
req, unquote(req.headers[TGT_ACCT_SYMLINK_HDR])) \
if TGT_ACCT_SYMLINK_HDR in req.headers else None
# Extract request path
_junk, req_acc, req_cont, req_obj = req.split_path(4, 4, True)
if not account:
account = req_acc
# Check if symlink targets the symlink itself or not
if (account, container, obj) == (req_acc, req_cont, req_obj):
raise HTTPBadRequest(
body='Symlink cannot target itself',
request=req, content_type='text/plain')
