src: add range expression

Add range expression available that is scheduled for linux kernel 4.9.
This range expression allows us to check if a given value placed in a
register is within/outside a specified interval.

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

1 files changed, 109 insertions, 0 deletions

diff --git a/tests/nft-expr_range-test.c b/tests/nft-expr_range-test.c
new file mode 100644
index 0000000..b92dfc0
--- /dev/null
+++ b/tests/nft-expr_range-test.c
@@ -0,0 +1,109 @@
+/*
+ * (C) 2013 by Ana Rey Botello <anarey@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <netinet/in.h>
+#include <netinet/ip.h>
+#include <linux/netfilter/nf_tables.h>
+#include <libmnl/libmnl.h>
+#include <libnftnl/rule.h>
+#include <libnftnl/expr.h>
+
+static int test_ok = 1;
+
+static void print_err(const char *msg)
+{
+	test_ok = 0;
+	printf("\033[31mERROR:\e[0m %s\n", msg);
+}
+
+static void range_nftnl_expr(struct nftnl_expr *rule_a,
+			     struct nftnl_expr *rule_b)
+{
+	uint32_t data_a, data_b;
+
+	nftnl_expr_get(rule_a, NFTNL_EXPR_RANGE_FROM_DATA, &data_a);
+	nftnl_expr_get(rule_b, NFTNL_EXPR_RANGE_FROM_DATA, &data_b);
+	if (data_a != data_b)
+		print_err("Size of NFTNL_EXPR_RANGE_FROM_DATA mismatches");
+	nftnl_expr_get(rule_a, NFTNL_EXPR_RANGE_TO_DATA, &data_a);
+	nftnl_expr_get(rule_b, NFTNL_EXPR_RANGE_TO_DATA, &data_b);
+	if (data_a != data_b)
+		print_err("Size of NFTNL_EXPR_RANGE_TO_DATA mismatches");
+	if (nftnl_expr_get_u32(rule_a, NFTNL_EXPR_RANGE_SREG) !=
+	    nftnl_expr_get_u32(rule_b, NFTNL_EXPR_RANGE_SREG))
+		print_err("Expr NFTNL_EXPR_RANGE_SREG mismatches");
+	if (nftnl_expr_get_u32(rule_a, NFTNL_EXPR_RANGE_OP) !=
+	    nftnl_expr_get_u32(rule_b, NFTNL_EXPR_RANGE_OP))
+		print_err("Expr NFTNL_EXPR_RANGE_OP mismatches");
+}
+
+int main(int argc, char *argv[])
+{
+	struct nftnl_rule *a, *b;
+	struct nftnl_expr *ex;
+	struct nlmsghdr *nlh;
+	char buf[4096];
+	struct nftnl_expr_iter *iter_a, *iter_b;
+	struct nftnl_expr *rule_a, *rule_b;
+	uint32_t data_a = 0x01010101, data_b = 0x02020202;
+
+	a = nftnl_rule_alloc();
+	b = nftnl_rule_alloc();
+	if (a == NULL || b == NULL)
+		print_err("OOM");
+	ex = nftnl_expr_alloc("range");
+	if (ex == NULL)
+		print_err("OOM");
+
+	nftnl_expr_set(ex, NFTNL_EXPR_RANGE_FROM_DATA,
+		       &data_a, sizeof(data_a));
+	nftnl_expr_set(ex, NFTNL_EXPR_RANGE_TO_DATA,
+		       &data_b, sizeof(data_b));
+	nftnl_expr_set_u32(ex, NFTNL_EXPR_RANGE_SREG, 0x12345678);
+	nftnl_expr_set_u32(ex, NFTNL_EXPR_RANGE_OP, 0x78123456);
+
+	nftnl_rule_add_expr(a, ex);
+
+	nlh = nftnl_rule_nlmsg_build_hdr(buf, NFT_MSG_NEWRULE, AF_INET, 0, 1234);
+	nftnl_rule_nlmsg_build_payload(nlh, a);
+
+	if (nftnl_rule_nlmsg_parse(nlh, b) < 0)
+		print_err("parsing problems");
+
+	iter_a = nftnl_expr_iter_create(a);
+	iter_b = nftnl_expr_iter_create(b);
+	if (iter_a == NULL || iter_b == NULL)
+		print_err("OOM");
+	rule_a = nftnl_expr_iter_next(iter_a);
+	rule_b = nftnl_expr_iter_next(iter_b);
+	if (rule_a == NULL || rule_b == NULL)
+		print_err("OOM");
+
+	range_nftnl_expr(rule_a, rule_b);
+
+	if (nftnl_expr_iter_next(iter_a) != NULL ||
+	    nftnl_expr_iter_next(iter_b) != NULL)
+		print_err("More 1 expr.");
+
+	nftnl_expr_iter_destroy(iter_a);
+	nftnl_expr_iter_destroy(iter_b);
+	nftnl_rule_free(a);
+	nftnl_rule_free(b);
+
+	if (!test_ok)
+		exit(EXIT_FAILURE);
+
+	printf("%s: \033[32mOK\e[0m\n", argv[0]);
+	return EXIT_SUCCESS;
+}