segtree: fix decomposition of unclosed intervals containing address prefixes

The code which decomposes unclosed intervals doesn't check for prefixes.  This
leads to incorrect output for sets which contain these.  For example,

  # nft -f - <<END
  table ip t {
    chain c {
      ip saddr 192.0.0.0/2 drop
      ip saddr 10.0.0.0/8 drop
      ip saddr { 192.0.0.0/2, 10.0.0.0/8 } drop
    }
  }
  table ip6 t {
    chain c {
      ip6 saddr ff00::/8 drop
      ip6 saddr fe80::/10 drop
      ip6 saddr { ff00::/8, fe80::/10 } drop
    }
  }
  END
  # nft list table ip6 t
  table ip6 t {
    chain c {
      ip6 saddr ff00::/8 drop
      ip6 saddr fe80::/10 drop
      ip6 saddr { fe80::/10, ff00::-ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff } drop
    }
  }
  # nft list table ip t
  table ip t {
    chain c {
      ip saddr 192.0.0.0/2 drop
      ip saddr 10.0.0.0/8 drop
      ip saddr { 10.0.0.0/8, 192.0.0.0-255.255.255.255 } drop
    }
  }

Instead of treating the final unclosed interval as a special case, reuse the
code which correctly handles closed intervals.

Add a shell test-case.

Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1018156
Fixes: 86b965bdab8d ("segtree: fix decomposition of unclosed intervals")
Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
Signed-off-by: Florian Westphal <fw@strlen.de>

2 files changed, 42 insertions, 0 deletions

diff --git a/tests/shell/testcases/sets/0071unclosed_prefix_interval_0 b/tests/shell/testcases/sets/0071unclosed_prefix_interval_0
new file mode 100755
index 00000000..79e3ca7d
--- /dev/null
+++ b/tests/shell/testcases/sets/0071unclosed_prefix_interval_0
@@ -0,0 +1,23 @@
+#!/bin/bash
+
+set -e
+
+RULESET="
+table inet t {
+	set s1 {
+		type ipv4_addr
+		flags interval
+		elements = { 192.0.0.0/2, 10.0.0.0/8 }
+	}
+	set s2 {
+		type ipv6_addr
+		flags interval
+		elements = { ff00::/8, fe80::/10 }
+	}
+	chain c {
+		ip saddr @s1 accept
+		ip6 daddr @s2 accept
+	}
+}"
+
+$NFT -f - <<< "$RULESET"
diff --git a/tests/shell/testcases/sets/dumps/0071unclosed_prefix_interval_0.nft b/tests/shell/testcases/sets/dumps/0071unclosed_prefix_interval_0.nft
new file mode 100644
index 00000000..4eed94c2
--- /dev/null
+++ b/tests/shell/testcases/sets/dumps/0071unclosed_prefix_interval_0.nft
@@ -0,0 +1,19 @@
+table inet t {
+	set s1 {
+		type ipv4_addr
+		flags interval
+		elements = { 10.0.0.0/8, 192.0.0.0/2 }
+	}
+
+	set s2 {
+		type ipv6_addr
+		flags interval
+		elements = { fe80::/10,
+			     ff00::/8 }
+	}
+
+	chain c {
+		ip saddr @s1 accept
+		ip6 daddr @s2 accept
+	}
+}