From 714a097ba82ad53b90cfff921ea3749cd1130f3e Mon Sep 17 00:00:00 2001
From: Dumitru Ceara <dceara@redhat.com>
Date: Tue, 23 Jun 2020 10:17:50 +0200
Subject: [PATCH] lex: Allow unmasked bits in value/mask tokens.

It's quite restrictive to not accept ACLs/policies that match on a CIDR
that has non-zero host bits. Right now this generates a lexer error that
can only be detected in the logs.

There's no real harm in automatically zero-ing the unmasked bits.

Reported-at: https://bugzilla.redhat.com/1812820
Reported-by: Ying Xu <yinxu@redhat.com>
Signed-off-by: Dumitru Ceara <dceara@redhat.com>
Acked-by: Mark Michelson <mmichels@redhat.com>
Signed-off-by: Numan Siddique <numans@ovn.org>
(cherry picked from upstream commit 2104f67aacd62f62a31f4e23a6720aeeaa751154)

Change-Id: I90c57fe51170d63fcd08d1a57d6d9555755a43be
---
 lib/lex.c    | 10 ++--------
 tests/ovn.at | 11 +++++++----
 2 files changed, 9 insertions(+), 12 deletions(-)

diff --git a/lib/lex.c b/lib/lex.c
index 94f6c77..4d92199 100644
--- a/lib/lex.c
+++ b/lib/lex.c
@@ -485,16 +485,10 @@ lex_parse_mask(const char *p, struct lex_token *token)
         return p;
     }
 
-    /* Check invariant that a 1-bit in the value corresponds to a 1-bit in the
+    /* Apply invariant that a 1-bit in the value corresponds to a 1-bit in the
      * mask. */
     for (int i = 0; i < ARRAY_SIZE(token->mask.be32); i++) {
-        ovs_be32 v = token->value.be32[i];
-        ovs_be32 m = token->mask.be32[i];
-
-        if (v & ~m) {
-            lex_error(token, "Value contains unmasked 1-bits.");
-            break;
-        }
+        token->value.be32[i] &= token->mask.be32[i];
     }
 
     /* Done! */
diff --git a/tests/ovn.at b/tests/ovn.at
index cf521af..e7e0439 100644
--- a/tests/ovn.at
+++ b/tests/ovn.at
@@ -79,7 +79,7 @@ a/b => a error("`/' is only valid as part of `//' or `/*'.") b
 
 0/0
 0/1
-1/0 => error("Value contains unmasked 1-bits.")
+1/0 => 0/0
 1/1
 128/384
 1/3
@@ -99,7 +99,7 @@ a/b => a error("`/' is only valid as part of `//' or `/*'.") b
 0X => error("Hex digits expected following 0X.")
 0x0/0x0 => 0/0
 0x0/0x1 => 0/0x1
-0x1/0x0 => error("Value contains unmasked 1-bits.")
+0x1/0x0 => 0/0
 0xffff/0x1ffff
 0x. => error("Invalid syntax in hexadecimal constant.")
 
@@ -109,9 +109,12 @@ a/b => a error("`/' is only valid as part of `//' or `/*'.") b
 192.168.0.0/255.255.0.0 => 192.168.0.0/16
 192.168.0.0/255.255.255.0 => 192.168.0.0/24
 192.168.0.0/255.255.0.255
-192.168.0.0/255.0.0.0 => error("Value contains unmasked 1-bits.")
+192.168.0.0/255.0.0.0 => 192.0.0.0/8
 192.168.0.0/32
 192.168.0.0/255.255.255.255 => 192.168.0.0/32
+192.168.0.2/32
+192.168.0.2/30 => 192.168.0.0/30
+192.168.0.2/24 => 192.168.0.0/24
 1.2.3.4:5 => 1.2.3.4 : 5
 
 ::
@@ -135,7 +138,7 @@ FE:DC:ba:98:76:54 => fe:dc:ba:98:76:54
 01:00:00:00:00:00/01:00:00:00:00:00
 ff:ff:ff:ff:ff:ff/ff:ff:ff:ff:ff:ff
 fe:ff:ff:ff:ff:ff/ff:ff:ff:ff:ff:ff
-ff:ff:ff:ff:ff:ff/fe:ff:ff:ff:ff:ff => error("Value contains unmasked 1-bits.")
+ff:ff:ff:ff:ff:ff/fe:ff:ff:ff:ff:ff => fe:ff:ff:ff:ff:ff/fe:ff:ff:ff:ff:ff
 fe:x => error("Invalid numeric constant.")
 00:01:02:03:04:x => error("Invalid numeric constant.")
 
-- 
1.8.3.1