1 files changed, 142 insertions, 0 deletions
diff --git a/src/expr/dup.c b/src/expr/dup.c
new file mode 100644
index 0000000..a239ff3
--- /dev/null
+++ b/src/expr/dup.c
@@ -0,0 +1,142 @@
+/*
+ * (C) 2015 Pablo Neira Ayuso <pablo@netfilter.org>
+ *
+ * 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 <stdint.h>
+#include <string.h>
+#include <arpa/inet.h>
+#include <errno.h>
+#include "internal.h"
+#include <libmnl/libmnl.h>
+#include <linux/netfilter/nf_tables.h>
+#include <libnftnl/expr.h>
+#include <libnftnl/rule.h>
+#include "expr_ops.h"
+#include "data_reg.h"
+
+struct nftnl_expr_dup {
+	enum nft_registers	sreg_addr;
+	enum nft_registers	sreg_dev;
+};
+
+static int nftnl_expr_dup_set(struct nftnl_expr *e, uint16_t type,
+			      const void *data, uint32_t data_len)
+{
+	struct nftnl_expr_dup *dup = nftnl_expr_data(e);
+
+	switch (type) {
+	case NFTNL_EXPR_DUP_SREG_ADDR:
+		memcpy(&dup->sreg_addr, data, sizeof(dup->sreg_addr));
+		break;
+	case NFTNL_EXPR_DUP_SREG_DEV:
+		memcpy(&dup->sreg_dev, data, sizeof(dup->sreg_dev));
+		break;
+	default:
+		return -1;
+	}
+	return 0;
+}
+
+static const void *nftnl_expr_dup_get(const struct nftnl_expr *e,
+				      uint16_t type, uint32_t *data_len)
+{
+	struct nftnl_expr_dup *dup = nftnl_expr_data(e);
+
+	switch (type) {
+	case NFTNL_EXPR_DUP_SREG_ADDR:
+		*data_len = sizeof(dup->sreg_addr);
+		return &dup->sreg_addr;
+	case NFTNL_EXPR_DUP_SREG_DEV:
+		*data_len = sizeof(dup->sreg_dev);
+		return &dup->sreg_dev;
+	}
+	return NULL;
+}
+
+static int nftnl_expr_dup_cb(const struct nlattr *attr, void *data)
+{
+	const struct nlattr **tb = data;
+	int type = mnl_attr_get_type(attr);
+
+	if (mnl_attr_type_valid(attr, NFTA_DUP_MAX) < 0)
+		return MNL_CB_OK;
+
+	switch (type) {
+	case NFTA_DUP_SREG_ADDR:
+	case NFTA_DUP_SREG_DEV:
+		if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
+			abi_breakage();
+		break;
+	}
+
+	tb[type] = attr;
+	return MNL_CB_OK;
+}
+
+static void nftnl_expr_dup_build(struct nlmsghdr *nlh,
+				 const struct nftnl_expr *e)
+{
+	struct nftnl_expr_dup *dup = nftnl_expr_data(e);
+
+	if (e->flags & (1 << NFTNL_EXPR_DUP_SREG_ADDR))
+		mnl_attr_put_u32(nlh, NFTA_DUP_SREG_ADDR, htonl(dup->sreg_addr));
+	if (e->flags & (1 << NFTNL_EXPR_DUP_SREG_DEV))
+		mnl_attr_put_u32(nlh, NFTA_DUP_SREG_DEV, htonl(dup->sreg_dev));
+}
+
+static int nftnl_expr_dup_parse(struct nftnl_expr *e, struct nlattr *attr)
+{
+	struct nftnl_expr_dup *dup = nftnl_expr_data(e);
+	struct nlattr *tb[NFTA_DUP_MAX + 1] = {};
+	int ret = 0;
+
+	if (mnl_attr_parse_nested(attr, nftnl_expr_dup_cb, tb) < 0)
+		return -1;
+
+	if (tb[NFTA_DUP_SREG_ADDR]) {
+		dup->sreg_addr = ntohl(mnl_attr_get_u32(tb[NFTA_DUP_SREG_ADDR]));
+		e->flags |= (1 << NFTNL_EXPR_DUP_SREG_ADDR);
+	}
+	if (tb[NFTA_DUP_SREG_DEV]) {
+		dup->sreg_dev = ntohl(mnl_attr_get_u32(tb[NFTA_DUP_SREG_DEV]));
+		e->flags |= (1 << NFTNL_EXPR_DUP_SREG_DEV);
+	}
+
+	return ret;
+}
+
+static int nftnl_expr_dup_snprintf(char *buf, size_t remain,
+				   uint32_t flags, const struct nftnl_expr *e)
+{
+	struct nftnl_expr_dup *dup = nftnl_expr_data(e);
+	int offset = 0, ret;
+
+	if (e->flags & (1 << NFTNL_EXPR_DUP_SREG_ADDR)) {
+		ret = snprintf(buf + offset, remain, "sreg_addr %u ", dup->sreg_addr);
+		SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+	}
+
+	if (e->flags & (1 << NFTNL_EXPR_DUP_SREG_DEV)) {
+		ret = snprintf(buf + offset, remain, "sreg_dev %u ", dup->sreg_dev);
+		SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+	}
+
+	return offset;
+}
+
+struct expr_ops expr_ops_dup = {
+	.name		= "dup",
+	.alloc_len	= sizeof(struct nftnl_expr_dup),
+	.max_attr	= NFTA_DUP_MAX,
+	.set		= nftnl_expr_dup_set,
+	.get		= nftnl_expr_dup_get,
+	.parse		= nftnl_expr_dup_parse,
+	.build		= nftnl_expr_dup_build,
+	.output		= nftnl_expr_dup_snprintf,
+};