netlink: rework range_expr_to_prefix()

Consolidate prefix calculation in range_expr_is_prefix().

Add tests/py for 9208fb30dc49 ("src: Check range bounds before converting to
prefix").

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 26 insertions, 0 deletions

diff --git a/tests/py/ip/snat.t.payload b/tests/py/ip/snat.t.payload
index 58b1c1a4..64f47896 100644
--- a/tests/py/ip/snat.t.payload
+++ b/tests/py/ip/snat.t.payload
@@ -60,6 +60,32 @@ ip test-ip4 postrouting
   [ immediate reg 1 0x0203a8c0 ]
   [ nat snat ip addr_min reg 1 ]
 
+# iifname "eth0" tcp dport 80-90 snat to 192.168.3.0-192.168.3.255
+ip
+  [ meta load iifname => reg 1 ]
+  [ cmp eq reg 1 0x30687465 0x00000000 0x00000000 0x00000000 ]
+  [ meta load l4proto => reg 1 ]
+  [ cmp eq reg 1 0x00000006 ]
+  [ payload load 2b @ transport header + 2 => reg 1 ]
+  [ cmp gte reg 1 0x00005000 ]
+  [ cmp lte reg 1 0x00005a00 ]
+  [ immediate reg 1 0x0003a8c0 ]
+  [ immediate reg 2 0xff03a8c0 ]
+  [ nat snat ip addr_min reg 1 addr_max reg 2 ]
+
+# iifname "eth0" tcp dport 80-90 snat to 192.168.3.15-192.168.3.240
+ip
+  [ meta load iifname => reg 1 ]
+  [ cmp eq reg 1 0x30687465 0x00000000 0x00000000 0x00000000 ]
+  [ meta load l4proto => reg 1 ]
+  [ cmp eq reg 1 0x00000006 ]
+  [ payload load 2b @ transport header + 2 => reg 1 ]
+  [ cmp gte reg 1 0x00005000 ]
+  [ cmp lte reg 1 0x00005a00 ]
+  [ immediate reg 1 0x0f03a8c0 ]
+  [ immediate reg 2 0xf003a8c0 ]
+  [ nat snat ip addr_min reg 1 addr_max reg 2 ]
+
 # snat ip to ip saddr map { 10.141.11.4 : 192.168.2.3 . 80 }
 __map%d test-ip4 b size 1
 __map%d test-ip4 0