diff options
| -rw-r--r-- | src/plugins/nat/nat44-ed/nat44_ed_in2out.c | 4 | ||||
| -rw-r--r-- | test/test_nat44_ed.py | 25 |
2 files changed, 15 insertions, 14 deletions
diff --git a/src/plugins/nat/nat44-ed/nat44_ed_in2out.c b/src/plugins/nat/nat44-ed/nat44_ed_in2out.c index deec0099933..4ba51bcaea6 100644 --- a/src/plugins/nat/nat44-ed/nat44_ed_in2out.c +++ b/src/plugins/nat/nat44-ed/nat44_ed_in2out.c @@ -155,7 +155,9 @@ nat_ed_alloc_addr_and_port (snat_main_t *sm, u32 rx_fib_index, { if (vec_len (sm->addresses) > 0) { - u32 s_addr_offset = s_addr.as_u32 % vec_len (sm->addresses); + u32 s_addr_offset = (s_addr.as_u32 + (s_addr.as_u32 >> 8) + + (s_addr.as_u32 >> 16) + (s_addr.as_u32 >> 24)) % + vec_len (sm->addresses); snat_address_t *a, *ja = 0, *ra = 0, *ba = 0; int i; diff --git a/test/test_nat44_ed.py b/test/test_nat44_ed.py index 1fbfff990b6..323249e4424 100644 --- a/test/test_nat44_ed.py +++ b/test/test_nat44_ed.py @@ -13,6 +13,7 @@ from scapy.layers.inet import IP, TCP, UDP, ICMP, GRE from scapy.layers.inet import IPerror, TCPerror from scapy.layers.l2 import Ether from scapy.packet import Raw +from statistics import variance from syslog_rfc5424_parser import SyslogMessage, ParseError from syslog_rfc5424_parser.constants import SyslogSeverity from util import ppp, pr, ip4_range @@ -2313,14 +2314,17 @@ class TestNAT44ED(VppTestCase): raise def test_outside_address_distribution(self): - """Outside address distribution based on source address""" + """NAT44ED outside address distribution based on source address""" + addresses = 65 x = 100 - nat_addresses = [] - for i in range(1, x): + nat_addresses = [] + nat_distribution = {} + for i in range(1, addresses): a = "10.0.0.%d" % i nat_addresses.append(a) + nat_distribution[a] = set() self.nat_add_inside_interface(self.pg0) self.nat_add_outside_interface(self.pg1) @@ -2359,16 +2363,11 @@ class TestNAT44ED(VppTestCase): self.assertTrue(info is not None) self.assertEqual(packet_index, info.index) p_sent = info.data - packed = socket.inet_aton(p_sent[IP].src) - numeric = struct.unpack("!L", packed)[0] - numeric = socket.htonl(numeric) - a = nat_addresses[(numeric - 1) % len(nat_addresses)] - self.assertEqual( - a, - p_recvd[IP].src, - "Invalid packet (src IP %s translated to %s, but expected %s)" - % (p_sent[IP].src, p_recvd[IP].src, a), - ) + self.assertIn(p_recvd[IP].src, nat_distribution) + nat_distribution[p_recvd[IP].src].add(p_sent[IP].src) + + var = variance(map(len, nat_distribution.values()), x / addresses) + self.assertLess(var, 0.33, msg="Bad outside address distribution") def test_dynamic_edge_ports(self): """NAT44ED dynamic translation test: edge ports""" |