src: Allow goto and jump to a variable

This patch introduces the use of nft input files variables in 'jump' and 'goto'
statements, e.g.

define dest = ber

add table ip foo
add chain ip foo bar {type filter hook input priority 0;}
add chain ip foo ber
add rule ip foo ber counter
add rule ip foo bar jump $dest

table ip foo {
        chain bar {
                type filter hook input priority filter; policy accept;
                jump ber
        }

        chain ber {
                counter packets 71 bytes 6664
        }
}

Signed-off-by: Fernando Fernandez Mancera <ffmancera@riseup.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

4 files changed, 67 insertions, 0 deletions

diff --git a/tests/shell/testcases/nft-f/0018jump_variable_0 b/tests/shell/testcases/nft-f/0018jump_variable_0
new file mode 100755
index 00000000..003a1bdf
--- /dev/null
+++ b/tests/shell/testcases/nft-f/0018jump_variable_0
@@ -0,0 +1,19 @@
+#!/bin/bash
+
+# Tests use of variables in jump statements
+
+set -e
+
+RULESET="
+define dest = ber
+
+table ip foo {
+	chain bar {
+		jump \$dest
+	}
+
+	chain ber {
+	}
+}"
+
+$NFT -f - <<< "$RULESET"
diff --git a/tests/shell/testcases/nft-f/0019jump_variable_1 b/tests/shell/testcases/nft-f/0019jump_variable_1
new file mode 100755
index 00000000..bda861c9
--- /dev/null
+++ b/tests/shell/testcases/nft-f/0019jump_variable_1
@@ -0,0 +1,20 @@
+#!/bin/bash
+
+# Tests use of variables in jump statements
+
+set -e
+
+RULESET="
+define dest = { 1024 }
+
+table ip foo {
+	chain bar {
+		jump \$dest
+	}
+
+	chain ber {
+	}
+}"
+
+$NFT -f - <<< "$RULESET" && exit 1
+exit 0
diff --git a/tests/shell/testcases/nft-f/0020jump_variable_1 b/tests/shell/testcases/nft-f/0020jump_variable_1
new file mode 100755
index 00000000..f753058f
--- /dev/null
+++ b/tests/shell/testcases/nft-f/0020jump_variable_1
@@ -0,0 +1,20 @@
+#!/bin/bash
+
+# Tests use of variables in jump statements
+
+set -e
+
+RULESET="
+define dest = *
+
+table ip foo {
+	chain bar {
+		jump \$dest
+	}
+
+	chain ber {
+	}
+}"
+
+$NFT -f - <<< "$RULESET" && exit 1
+exit 0
diff --git a/tests/shell/testcases/nft-f/dumps/0018jump_variable_0.nft b/tests/shell/testcases/nft-f/dumps/0018jump_variable_0.nft
new file mode 100644
index 00000000..0ddaf07f
--- /dev/null
+++ b/tests/shell/testcases/nft-f/dumps/0018jump_variable_0.nft
@@ -0,0 +1,8 @@
+table ip foo {
+	chain bar {
+		jump ber
+	}
+
+	chain ber {
+	}
+}