@@ -8,6 +8,7 @@ import argparse
import errno
import ipaddress
import logging
+import math
import multiprocessing
import re
import socket
@@ -60,6 +61,7 @@ OVS_FLOW_CMD_DEL = 2
OVS_FLOW_CMD_GET = 3
OVS_FLOW_CMD_SET = 4
+UINT32_MAX = 0xFFFFFFFF
def macstr(mac):
outstr = ":".join(["%02X" % i for i in mac])
@@ -281,6 +283,75 @@ def parse_extract_field(
return str_skipped, data
+def parse_attrs(actstr, attr_desc):
+ """Parses the given action string and returns a list of netlink
+ attributes based on a list of attribute descriptions.
+
+ Each element in the attribute description list is a tuple such as:
+ (name, attr_name, parse_func)
+ where:
+ name: is the string representing the attribute
+ attr_name: is the name of the attribute as defined in the uAPI.
+ parse_func: is a callable accepting a string and returning either
+ a single object (the parsed attribute value) or a tuple of
+ two values (the parsed attribute value and the remaining string)
+
+ Returns a list of attributes and the remaining string.
+ """
+ def parse_attr(actstr, key, func):
+ actstr = actstr[len(key) :]
+
+ if not func:
+ return None, actstr
+
+ delim = actstr[0]
+ actstr = actstr[1:]
+
+ if delim == "=":
+ pos = strcspn(actstr, ",)")
+ ret = func(actstr[:pos])
+ else:
+ ret = func(actstr)
+
+ if isinstance(ret, tuple):
+ (datum, actstr) = ret
+ else:
+ datum = ret
+ actstr = actstr[strcspn(actstr, ",)"):]
+
+ if delim == "(":
+ if not actstr or actstr[0] != ")":
+ raise ValueError("Action contains unbalanced parentheses")
+
+ actstr = actstr[1:]
+
+ actstr = actstr[strspn(actstr, ", ") :]
+
+ return datum, actstr
+
+ attrs = []
+ attr_desc = list(attr_desc)
+ while actstr and actstr[0] != ")" and attr_desc:
+ found = False
+ for i, (key, attr, func) in enumerate(attr_desc):
+ if actstr.startswith(key):
+ datum, actstr = parse_attr(actstr, key, func)
+ attrs.append([attr, datum])
+ found = True
+ del attr_desc[i]
+
+ if not found:
+ raise ValueError("Unknown attribute: '%s'" % actstr)
+
+ actstr = actstr[strspn(actstr, ", ") :]
+
+ if actstr[0] != ")":
+ raise ValueError("Action string contains extra garbage or has "
+ "unbalanced parenthesis: '%s'" % actstr)
+
+ return attrs, actstr[1:]
+
+
class ovs_dp_msg(genlmsg):
# include the OVS version
# We need a custom header rather than just being able to rely on
@@ -299,7 +370,7 @@ class ovsactions(nla):
("OVS_ACTION_ATTR_SET", "ovskey"),
("OVS_ACTION_ATTR_PUSH_VLAN", "none"),
("OVS_ACTION_ATTR_POP_VLAN", "flag"),
- ("OVS_ACTION_ATTR_SAMPLE", "none"),
+ ("OVS_ACTION_ATTR_SAMPLE", "sample"),
("OVS_ACTION_ATTR_RECIRC", "uint32"),
("OVS_ACTION_ATTR_HASH", "none"),
("OVS_ACTION_ATTR_PUSH_MPLS", "none"),
@@ -318,8 +389,85 @@ class ovsactions(nla):
("OVS_ACTION_ATTR_ADD_MPLS", "none"),
("OVS_ACTION_ATTR_DEC_TTL", "none"),
("OVS_ACTION_ATTR_DROP", "uint32"),
+ ("OVS_ACTION_ATTR_PSAMPLE", "psample"),
)
+ class psample(nla):
+ nla_flags = NLA_F_NESTED
+
+ nla_map = (
+ ("OVS_PSAMPLE_ATTR_UNSPEC", "none"),
+ ("OVS_PSAMPLE_ATTR_GROUP", "uint32"),
+ ("OVS_PSAMPLE_ATTR_COOKIE", "array(uint8)"),
+ )
+
+ def dpstr(self, more=False):
+ args = "group=%d" % self.get_attr("OVS_PSAMPLE_ATTR_GROUP")
+
+ cookie = self.get_attr("OVS_PSAMPLE_ATTR_COOKIE")
+ if cookie:
+ args += ",cookie(%s)" % \
+ "".join(format(x, "02x") for x in cookie)
+
+ return "psample(%s)" % args
+
+ def parse(self, actstr):
+ desc = (
+ ("group", "OVS_PSAMPLE_ATTR_GROUP", int),
+ ("cookie", "OVS_PSAMPLE_ATTR_COOKIE",
+ lambda x: list(bytearray.fromhex(x)))
+ )
+
+ attrs, actstr = parse_attrs(actstr, desc)
+
+ for attr in attrs:
+ self["attrs"].append(attr)
+
+ return actstr
+
+ class sample(nla):
+ nla_flags = NLA_F_NESTED
+
+ nla_map = (
+ ("OVS_SAMPLE_ATTR_UNSPEC", "none"),
+ ("OVS_SAMPLE_ATTR_PROBABILITY", "uint32"),
+ ("OVS_SAMPLE_ATTR_ACTIONS", "ovsactions"),
+ )
+
+ def dpstr(self, more=False):
+ args = []
+
+ args.append("sample={:.2f}%".format(
+ 100 * self.get_attr("OVS_SAMPLE_ATTR_PROBABILITY") /
+ UINT32_MAX))
+
+ actions = self.get_attr("OVS_SAMPLE_ATTR_ACTIONS")
+ if actions:
+ args.append("actions(%s)" % actions.dpstr(more))
+
+ return "sample(%s)" % ",".join(args)
+
+ def parse(self, actstr):
+ def parse_nested_actions(actstr):
+ subacts = ovsactions()
+ parsed_len = subacts.parse(actstr)
+ return subacts, actstr[parsed_len :]
+
+ def percent_to_rate(percent):
+ percent = float(percent.strip('%'))
+ return int(math.floor(UINT32_MAX * (percent / 100.0) + .5))
+
+ desc = (
+ ("sample", "OVS_SAMPLE_ATTR_PROBABILITY", percent_to_rate),
+ ("actions", "OVS_SAMPLE_ATTR_ACTIONS", parse_nested_actions),
+ )
+ attrs, actstr = parse_attrs(actstr, desc)
+
+ for attr in attrs:
+ self["attrs"].append(attr)
+
+ return actstr
+
class ctact(nla):
nla_flags = NLA_F_NESTED
@@ -683,6 +831,18 @@ class ovsactions(nla):
self["attrs"].append(["OVS_ACTION_ATTR_CT", ctact])
parsed = True
+ elif parse_starts_block(actstr, "sample(", False):
+ sampleact = self.sample()
+ actstr = sampleact.parse(actstr[len("sample(") : ])
+ self["attrs"].append(["OVS_ACTION_ATTR_SAMPLE", sampleact])
+ parsed = True
+
+ elif parse_starts_block(actstr, "psample(", False):
+ psampleact = self.psample()
+ actstr = psampleact.parse(actstr[len("psample(") : ])
+ self["attrs"].append(["OVS_ACTION_ATTR_PSAMPLE", psampleact])
+ parsed = True
+
actstr = actstr[strspn(actstr, ", ") :]
while parencount > 0:
parencount -= 1