qos: T4284: first implementation introducing a new vyos.qos module

1 files changed, 177 insertions, 13 deletions

diff --git a/src/conf_mode/qos.py b/src/conf_mode/qos.py
index dbe3be225..7e94e95bf 100755
--- a/src/conf_mode/qos.py
+++ b/src/conf_mode/qos.py
@@ -15,14 +15,59 @@
 # along with this program. If not, see <http://www.gnu.org/licenses/>.
 
 from sys import exit
+from netifaces import interfaces
 
 from vyos.config import Config
 from vyos.configdict import dict_merge
+from vyos.configverify import verify_interface_exists
+from vyos.qos import CAKE
+from vyos.qos import DropTail
+from vyos.qos import FairQueue
+from vyos.qos import FQCodel
+from vyos.qos import Limiter
+from vyos.qos import NetEm
+from vyos.qos import Priority
+from vyos.qos import RandomDetect
+from vyos.qos import RateLimiter
+from vyos.qos import RoundRobin
+from vyos.qos import TrafficShaper
+from vyos.qos import TrafficShaperHFSC
+from vyos.util import call
+from vyos.util import dict_search_recursive
 from vyos.xml import defaults
 from vyos import ConfigError
 from vyos import airbag
 airbag.enable()
 
+map_vyops_tc = {
+    'cake'             : CAKE,
+    'drop_tail'        : DropTail,
+    'fair_queue'       : FairQueue,
+    'fq_codel'         : FQCodel,
+    'limiter'          : Limiter,
+    'network_emulator' : NetEm,
+    'priority_queue'   : Priority,
+    'random_detect'    : RandomDetect,
+    'rate_control'     : RateLimiter,
+    'round_robin'      : RoundRobin,
+    'shaper'           : TrafficShaper,
+    'shaper_hfsc'      : TrafficShaperHFSC,
+}
+
+def get_shaper(qos, interface_config, direction):
+    policy_name = interface_config[direction]
+    # An interface might have a QoS configuration, search the used
+    # configuration referenced by this. Path will hold the dict element
+    # referenced by the config, as this will be of sort:
+    #
+    # ['policy', 'drop_tail', 'foo-dtail'] <- we are only interested in
+    # drop_tail as the policy/shaper type
+    _, path = next(dict_search_recursive(qos, policy_name))
+    shaper_type = path[1]
+    shaper_config = qos['policy'][shaper_type][policy_name]
+
+    return (map_vyops_tc[shaper_type], shaper_config)
+
 def get_config(config=None):
     if config:
         conf = config
@@ -32,48 +77,167 @@ def get_config(config=None):
     if not conf.exists(base):
         return None
 
-    qos = conf.get_config_dict(base, key_mangling=('-', '_'), get_first_key=True)
+    qos = conf.get_config_dict(base, key_mangling=('-', '_'),
+                               get_first_key=True,
+                               no_tag_node_value_mangle=True)
 
     if 'policy' in qos:
         for policy in qos['policy']:
-            # CLI mangles - to _ for better Jinja2 compatibility - do we need
-            # Jinja2 here?
-            policy = policy.replace('-','_')
+            # when calling defaults() we need to use the real CLI node, thus we
+            # need a hyphen
+            policy_hyphen = policy.replace('_', '-')
+
+            if policy in ['random_detect']:
+                for rd_name, rd_config in qos['policy'][policy].items():
+                    # There are eight precedence levels - ensure all are present
+                    # to be filled later down with the appropriate default values
+                    default_precedence = {'precedence' : { '0' : {}, '1' : {}, '2' : {}, '3' : {},
+                                                           '4' : {}, '5' : {}, '6' : {}, '7' : {} }}
+                    qos['policy']['random_detect'][rd_name] = dict_merge(
+                        default_precedence, qos['policy']['random_detect'][rd_name])
+
+            for p_name, p_config in qos['policy'][policy].items():
+                default_values = defaults(base + ['policy', policy_hyphen])
 
-            default_values = defaults(base + ['policy', policy])
+                if policy in ['priority_queue']:
+                    if 'default' not in p_config:
+                        raise ConfigError(f'QoS policy {p_name} misses "default" class!')
 
-            # class is another tag node which requires individual handling
-            class_default_values = defaults(base + ['policy', policy, 'class'])
-            if 'class' in default_values:
-                del default_values['class']
+                # XXX: T2665: we can not safely rely on the defaults() when there are
+                # tagNodes in place, it is better to blend in the defaults manually.
+                if 'class' in default_values:
+                    del default_values['class']
+                if 'precedence' in default_values:
+                    del default_values['precedence']
 
-            for p_name, p_config in qos['policy'][policy].items():
                 qos['policy'][policy][p_name] = dict_merge(
                     default_values, qos['policy'][policy][p_name])
 
+                # class is another tag node which requires individual handling
                 if 'class' in p_config:
+                    default_values = defaults(base + ['policy', policy_hyphen, 'class'])
                     for p_class in p_config['class']:
                         qos['policy'][policy][p_name]['class'][p_class] = dict_merge(
-                            class_default_values, qos['policy'][policy][p_name]['class'][p_class])
+                            default_values, qos['policy'][policy][p_name]['class'][p_class])
+
+                if 'precedence' in p_config:
+                    default_values = defaults(base + ['policy', policy_hyphen, 'precedence'])
+                    # precedence values are a bit more complex as they are calculated
+                    # under specific circumstances - thus we need to iterate two times.
+                    # first blend in the defaults from XML / CLI
+                    for precedence in p_config['precedence']:
+                        qos['policy'][policy][p_name]['precedence'][precedence] = dict_merge(
+                            default_values, qos['policy'][policy][p_name]['precedence'][precedence])
+                    # second calculate defaults based on actual dictionary
+                    for precedence in p_config['precedence']:
+                        max_thr = int(qos['policy'][policy][p_name]['precedence'][precedence]['maximum_threshold'])
+                        if 'minimum_threshold' not in qos['policy'][policy][p_name]['precedence'][precedence]:
+                            qos['policy'][policy][p_name]['precedence'][precedence]['minimum_threshold'] = str(
+                                int((9 + int(precedence)) * max_thr) // 18);
+
+                        if 'queue_limit' not in qos['policy'][policy][p_name]['precedence'][precedence]:
+                            qos['policy'][policy][p_name]['precedence'][precedence]['queue_limit'] = \
+                                str(int(4 * max_thr))
 
     import pprint
     pprint.pprint(qos)
+
     return qos
 
 def verify(qos):
-    if not qos:
+    if not qos or 'interface' not in qos:
         return None
 
     # network policy emulator
     # reorder rerquires delay to be set
+    if 'policy' in qos:
+        for policy_type in qos['policy']:
+            for policy, policy_config in qos['policy'][policy_type].items():
+                # a policy with it's given name is only allowed to exist once
+                # on the system. This is because an interface selects a policy
+                # for ingress/egress traffic, and thus there can only be one
+                # policy with a given name.
+                #
+                # We check if the policy name occurs more then once - error out
+                # if this is true
+                counter = 0
+                for _, path in dict_search_recursive(qos['policy'], policy):
+                    counter += 1
+                    if counter > 1:
+                        raise ConfigError(f'Conflicting policy name "{policy}", already in use!')
+
+                if 'class' in policy_config:
+                    for cls, cls_config in policy_config['class'].items():
+                        # bandwidth is not mandatory for priority-queue - that is why this is on the exception list
+                        if 'bandwidth' not in cls_config and policy_type not in ['priority_queue', 'round_robin']:
+                            raise ConfigError(f'Bandwidth must be defined for policy "{policy}" class "{cls}"!')
+                    if 'match' in cls_config:
+                        for match, match_config in cls_config['match'].items():
+                            if {'ip', 'ipv6'} <= set(match_config):
+                                 raise ConfigError(f'Can not use both IPv6 and IPv4 in one match ({match})!')
+
+                if policy_type in ['random_detect']:
+                    if 'precedence' in policy_config:
+                        for precedence, precedence_config in policy_config['precedence'].items():
+                            max_tr = int(precedence_config['maximum_threshold'])
+                            if {'maximum_threshold', 'minimum_threshold'} <= set(precedence_config):
+                                min_tr = int(precedence_config['minimum_threshold'])
+                                if min_tr >= max_tr:
+                                    raise ConfigError(f'Policy "{policy}" uses min-threshold "{min_tr}" >= max-threshold "{max_tr}"!')
+
+                            if {'maximum_threshold', 'queue_limit'} <= set(precedence_config):
+                                queue_lim = int(precedence_config['queue_limit'])
+                                if queue_lim < max_tr:
+                                    raise ConfigError(f'Policy "{policy}" uses queue-limit "{queue_lim}" < max-threshold "{max_tr}"!')
+
+
+    # we should check interface ingress/egress configuration after verifying that
+    # the policy name is used only once - this makes the logic easier!
+    for interface, interface_config in qos['interface'].items():
+        verify_interface_exists(interface)
+
+        for direction in ['egress', 'ingress']:
+            # bail out early if shaper for given direction is not used at all
+            if direction not in interface_config:
+                continue
+
+            policy_name = interface_config[direction]
+            if 'policy' not in qos or list(dict_search_recursive(qos['policy'], policy_name)) == []:
+                raise ConfigError(f'Selected QoS policy "{policy_name}" does not exist!')
+
+            shaper_type, shaper_config = get_shaper(qos, interface_config, direction)
+            tmp = shaper_type(interface).get_direction()
+            if direction not in tmp:
+                raise ConfigError(f'Selected QoS policy on interface "{interface}" only supports "{tmp}"!')
 
-    raise ConfigError('123')
     return None
 
 def generate(qos):
+    if not qos or 'interface' not in qos:
+        return None
+
     return None
 
 def apply(qos):
+    # Always delete "old" shapers first
+    for interface in interfaces():
+        # Ignore errors (may have no qdisc)
+        call(f'tc qdisc del dev {interface} parent ffff:')
+        call(f'tc qdisc del dev {interface} root')
+
+    if not qos or 'interface' not in qos:
+        return None
+
+    for interface, interface_config in qos['interface'].items():
+        for direction in ['egress', 'ingress']:
+            # bail out early if shaper for given direction is not used at all
+            if direction not in interface_config:
+                continue
+
+            shaper_type, shaper_config = get_shaper(qos, interface_config, direction)
+            tmp = shaper_type(interface)
+            tmp.update(shaper_config, direction)
+
     return None
 
 if __name__ == '__main__':