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mirror of https://github.com/retspen/webvirtcloud synced 2026-11-09 19:56:48 +00:00
webvirtcloud/vrtManager/nwfilters.py
catborise a95ec40f69 fix(virtsecrets): a secret in use is not deleted, and a password is stored as typed
- A secret is in use when a VM names it in a disk, a host device or its
  vTPM, or a pool in its source, by UUID or by its usage within the usage
  type, as they run and as saved. The vTPM, host devices and pools' saved
  definitions were not checked before.
- A Ceph key is taken in base64, as `ceph auth get-key` prints it; any other
  value is a password or passphrase stored as typed, spaces included.
- A new secret takes its value at once; a value refused leaves no secret.
- TLS and vTPM secrets can be created; the usage has no length limit.
- Every POST redirects; the list is read once and only with its users; a
  secret, VM or pool gone meanwhile is left out.
- domain_trees() is shared by the in-use checks of secrets, network filters,
  networks and pools; the storage page's Ceph secret picker reads the same
  listing.
2026-10-29 10:10:43 +03:00

195 lines
8.7 KiB
Python

import copy
import re
from functools import cached_property
from lxml import etree
from vrtManager import util
from vrtManager.connection import wvmConnect
# the names the panel gives filters: letters, digits, dots, dashes and underscores
NAME = re.compile(r"[A-Za-z0-9._-]+")
def element_text(element):
"""An element as the page shows it and sends it back: a rule or reference
is changed only while it still reads the same."""
return same_text(etree.tostring(element, encoding="unicode", with_tail=False))
def same_text(text):
"""text without the space between its tags, which a browser may send
back with other line breaks."""
return re.sub(r">\s+<", "><", text.strip())
def filter_info(nwfilter, tree):
"""What a filter and its XML tell: name, UUID, chain, priority, how many
rules it has and the filters it references."""
return {"name": nwfilter.name(), "uuid": nwfilter.UUIDString(), "chain": tree.get("chain"),
"priority": tree.get("priority"), "rules": len(tree.findall("rule")),
"refs": [ref.get("filter") for ref in tree.findall("filterref")]}
class wvmNWFilters(wvmConnect):
def get_nwfilters_info(self):
"""Every filter of the host (filter_info), with the filters that
reference it, by name: one listing, one XML read per filter."""
filters = [filter_info(nwfilter, etree.fromstring(nwfilter.XMLDesc(0)))
for nwfilter in self.wvm.listAllNWFilters(0)]
for nwfilter in filters:
nwfilter["referenced_by"] = [other["name"] for other in filters if nwfilter["name"] in other["refs"]]
return sorted(filters, key=lambda nwfilter: nwfilter["name"])
def get_users(self):
"""The VMs whose interfaces reference each filter, by filter name, in
any of their definitions (domain_trees)."""
users = {}
for vm, trees in self.domain_trees():
names = set()
for tree in trees:
names.update(tree.xpath("devices/interface/filterref/@filter"))
for name in names:
users.setdefault(name, []).append(vm)
return users
def create_nwfilter(self, xml):
"""Define a filter from the XML entered: one whose name or UUID the
host has is refused, as it would replace that filter."""
tree = util.parse_xml(xml)
if tree.tag != "filter":
raise util.OperationError("Enter one <filter> element")
if not NAME.fullmatch(tree.get("name") or ""):
raise util.OperationError("The filter's name may have letters, digits, dots, dashes and underscores")
for nwfilter in self.wvm.listAllNWFilters(0):
if nwfilter.name() == tree.get("name"):
raise util.OperationError("A network filter with this name already exists")
if nwfilter.UUIDString() == tree.findtext("uuid"):
raise util.OperationError("A network filter with this UUID already exists")
self.wvm.nwfilterDefineXML(xml)
def clone_nwfilter(self, name, clone_name):
"""Define a copy of filter name as clone_name, with its rules,
references and their parameters, and a UUID of its own."""
if not NAME.fullmatch(clone_name):
raise util.OperationError("The filter's name may have letters, digits, dots, dashes and underscores")
if clone_name in self.get_nwfilters():
raise util.OperationError(f"A network filter named {clone_name} already exists")
tree = etree.fromstring(self.get_nwfilter(name).XMLDesc(0))
tree.set("name", clone_name)
tree.remove(tree.find("uuid"))
self.wvm.nwfilterDefineXML(etree.tostring(tree, encoding="unicode"))
def delete_nwfilter(self, name):
"""Undefine a filter that no VM's interface and no other filter
references. libvirt refuses only one a running VM uses; a stopped VM,
or a VM using a filter that references it, would not start."""
vms = self.get_users().get(name, [])
if vms:
raise util.OperationError(f"Filter {name} is used by VM {', '.join(vms)}")
referencing = [nwfilter["name"] for nwfilter in self.get_nwfilters_info() if name in nwfilter["refs"]]
if referencing:
raise util.OperationError(f"Filter {name} is referenced by filter {', '.join(referencing)}")
self.get_nwfilter(name).undefine()
class wvmNWFilter(wvmNWFilters):
"""A filter of the host. A page reads its XML once (tree); a change is
the filter defined again with its UUID, which libvirt does in place, also
while a VM uses it, and refuses for XML it cannot parse or apply to the
running VMs' interfaces."""
def __init__(self, host, login, passwd, conn, nwfiltername):
wvmNWFilters.__init__(self, host, login, passwd, conn)
self.nwfilter = self.get_nwfilter(nwfiltername)
@cached_property
def tree(self):
return etree.fromstring(self.nwfilter.XMLDesc(0))
def get_uuid(self):
return self.nwfilter.UUIDString()
def get_name(self):
return self.nwfilter.name()
def get_xml(self):
return etree.tostring(self.tree, encoding="unicode")
def get_refs(self):
"""The filters it references, each with its parameters in order (one
name may repeat, giving a list) and its text."""
return [{"filter": ref.get("filter"), "text": element_text(ref),
"parameters": [(param.get("name"), param.get("value")) for param in ref.findall("parameter")]}
for ref in self.tree.findall("filterref")]
def get_rules(self):
"""Its rules: action, direction, priority, statematch, each protocol
element with its attributes (one rule may have several of one
protocol, a match and a negated one) and the rule's text."""
rules = []
for rule in self.tree.findall("rule"):
protocols = [{"name": protocol.tag, "attributes": list(protocol.attrib.items())} for protocol in rule]
rules.append({"action": rule.get("action"), "direction": rule.get("direction"),
"priority": rule.get("priority"), "statematch": rule.get("statematch"),
"protocols": protocols, "text": element_text(rule)})
return rules
def get_ref_choices(self):
"""The filters a reference can be added to: not this one, nor one it
references already."""
taken = {self.get_name(), *(ref.get("filter") for ref in self.tree.findall("filterref"))}
return [name for name in sorted(self.get_nwfilters()) if name not in taken]
def _define(self, tree):
self.wvm.nwfilterDefineXML(etree.tostring(tree, encoding="unicode"))
def _without(self, tag, index, text):
"""The filter without its tag element at index, which must still read
as text: a filter changed since the page was read loses nothing else.
Returns the element removed."""
tree = copy.deepcopy(self.tree)
elements = tree.findall(tag)
try:
index = int(index)
except ValueError:
index = -1
if not 0 <= index < len(elements) or element_text(elements[index]) != same_text(text):
raise util.OperationError("The filter has changed; reload the page and try again")
tree.remove(elements[index])
self._define(tree)
return elements[index]
def edit(self, xml):
"""Define the filter anew from the XML entered: the same filter, of
its name and UUID."""
tree = util.parse_xml(xml)
if tree.tag != "filter" or tree.get("name") != self.get_name():
raise util.OperationError(f"The XML must define filter {self.get_name()}")
if tree.findtext("uuid") != self.get_uuid():
raise util.OperationError("The XML must keep the filter's UUID")
self.wvm.nwfilterDefineXML(xml)
def delete_rule(self, index, text):
self._without("rule", index, text)
def delete_ref(self, index, text):
"""Returns the name of the filter it referenced."""
return self._without("filterref", index, text).get("filter")
def add_ref(self, name):
if name not in self.get_ref_choices():
raise util.OperationError(f"Filter {name} cannot be referenced: it is this one, referenced already or not on the host")
tree = copy.deepcopy(self.tree)
etree.SubElement(tree, "filterref", filter=name)
self._define(tree)
def add_rule(self, xml):
"""The filter with the rule added as entered; libvirt keeps one
protocol per rule, so it is never merged into another rule."""
rule = util.parse_xml(xml)
if rule.tag != "rule":
raise util.OperationError("Enter one <rule> element")
tree = copy.deepcopy(self.tree)
tree.append(rule)
self._define(tree)