1 files changed, 133 insertions, 0 deletions
diff --git a/iptables/nft-ruleparse-ipv4.c b/iptables/nft-ruleparse-ipv4.c
new file mode 100644
index 00000000..fe65b33c
--- /dev/null
+++ b/iptables/nft-ruleparse-ipv4.c
@@ -0,0 +1,133 @@
+/*
+ * (C) 2012-2014 by Pablo Neira Ayuso <pablo@netfilter.org>
+ * (C) 2013 by Tomasz Bursztyka <tomasz.bursztyka@linux.intel.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.
+ *
+ * This code has been sponsored by Sophos Astaro <http://www.sophos.com>
+ */
+
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <netdb.h>
+#include <net/if.h>
+#include <netinet/if_ether.h>
+#include <netinet/ip.h>
+
+#include <libnftnl/rule.h>
+#include <libnftnl/expr.h>
+
+#include "nft-shared.h"
+#include "nft-ruleparse.h"
+#include "xshared.h"
+
+static void nft_ipv4_parse_meta(struct nft_xt_ctx *ctx,
+				const struct nft_xt_ctx_reg *reg,
+				struct nftnl_expr *e,
+				struct iptables_command_state *cs)
+{
+	switch (reg->meta_dreg.key) {
+	case NFT_META_L4PROTO:
+		cs->fw.ip.proto = nftnl_expr_get_u8(e, NFTNL_EXPR_CMP_DATA);
+		if (nftnl_expr_get_u32(e, NFTNL_EXPR_CMP_OP) == NFT_CMP_NEQ)
+			cs->fw.ip.invflags |= XT_INV_PROTO;
+		return;
+	default:
+		break;
+	}
+
+	if (parse_meta(ctx, e, reg->meta_dreg.key, cs->fw.ip.iniface,
+		       cs->fw.ip.outiface, &cs->fw.ip.invflags) == 0)
+		return;
+
+	ctx->errmsg = "unknown ipv4 meta key";
+}
+
+static void parse_mask_ipv4(const struct nft_xt_ctx_reg *sreg, struct in_addr *mask)
+{
+	mask->s_addr = sreg->bitwise.mask[0];
+}
+
+static bool get_frag(const struct nft_xt_ctx_reg *reg, struct nftnl_expr *e)
+{
+	uint8_t op;
+
+	/* we assume correct mask and xor */
+	if (!reg->bitwise.set)
+		return false;
+
+	/* we assume correct data */
+	op = nftnl_expr_get_u32(e, NFTNL_EXPR_CMP_OP);
+	if (op == NFT_CMP_EQ)
+		return true;
+
+	return false;
+}
+
+static void nft_ipv4_parse_payload(struct nft_xt_ctx *ctx,
+				   const struct nft_xt_ctx_reg *sreg,
+				   struct nftnl_expr *e,
+				   struct iptables_command_state *cs)
+{
+	struct in_addr addr;
+	uint8_t proto;
+	bool inv;
+
+	switch (sreg->payload.offset) {
+	case offsetof(struct iphdr, saddr):
+		get_cmp_data(e, &addr, sizeof(addr), &inv);
+		cs->fw.ip.src.s_addr = addr.s_addr;
+		if (sreg->bitwise.set) {
+			parse_mask_ipv4(sreg, &cs->fw.ip.smsk);
+		} else {
+			memset(&cs->fw.ip.smsk, 0xff,
+			       min(sreg->payload.len, sizeof(struct in_addr)));
+		}
+
+		if (inv)
+			cs->fw.ip.invflags |= IPT_INV_SRCIP;
+		break;
+	case offsetof(struct iphdr, daddr):
+		get_cmp_data(e, &addr, sizeof(addr), &inv);
+		cs->fw.ip.dst.s_addr = addr.s_addr;
+		if (sreg->bitwise.set)
+			parse_mask_ipv4(sreg, &cs->fw.ip.dmsk);
+		else
+			memset(&cs->fw.ip.dmsk, 0xff,
+			       min(sreg->payload.len, sizeof(struct in_addr)));
+
+		if (inv)
+			cs->fw.ip.invflags |= IPT_INV_DSTIP;
+		break;
+	case offsetof(struct iphdr, protocol):
+		get_cmp_data(e, &proto, sizeof(proto), &inv);
+		cs->fw.ip.proto = proto;
+		if (inv)
+			cs->fw.ip.invflags |= IPT_INV_PROTO;
+		break;
+	case offsetof(struct iphdr, frag_off):
+		cs->fw.ip.flags |= IPT_F_FRAG;
+		inv = get_frag(sreg, e);
+		if (inv)
+			cs->fw.ip.invflags |= IPT_INV_FRAG;
+		break;
+	case offsetof(struct iphdr, ttl):
+		if (nft_parse_hl(ctx, e, cs) < 0)
+			ctx->errmsg = "invalid ttl field match";
+		break;
+	default:
+		DEBUGP("unknown payload offset %d\n", sreg->payload.offset);
+		ctx->errmsg = "unknown payload offset";
+		break;
+	}
+}
+
+struct nft_ruleparse_ops nft_ruleparse_ops_ipv4 = {
+	.meta		= nft_ipv4_parse_meta,
+	.payload	= nft_ipv4_parse_payload,
+};