1 files changed, 136 insertions, 0 deletions
diff --git a/src/socket.c b/src/socket.c
new file mode 100644
index 0000000..8a149e6
--- /dev/null
+++ b/src/socket.c
@@ -0,0 +1,136 @@
+/*
+ * Socket expression/statement related definition and types.
+ *
+ * Copyright (c) 2018 Máté Eckl <ecklm94@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 (or any
+ * later) as published by the Free Software Foundation.
+ */
+
+#include <nft.h>
+
+#include <nftables.h>
+#include <expression.h>
+#include <socket.h>
+#include <json.h>
+
+const struct socket_template socket_templates[] = {
+	[NFT_SOCKET_TRANSPARENT] = {
+		.token		= "transparent",
+		.dtype		= &integer_type,
+		.len		= BITS_PER_BYTE,
+		.byteorder	= BYTEORDER_HOST_ENDIAN,
+	},
+	[NFT_SOCKET_MARK] = {
+		.token		= "mark",
+		.dtype		= &mark_type,
+		.len		= 4 * BITS_PER_BYTE,
+		.byteorder	= BYTEORDER_HOST_ENDIAN,
+	},
+	[NFT_SOCKET_WILDCARD] = {
+		.token		= "wildcard",
+		.dtype		= &integer_type,
+		.len		= BITS_PER_BYTE,
+		.byteorder	= BYTEORDER_HOST_ENDIAN,
+	},
+	[NFT_SOCKET_CGROUPV2] = {
+		.token		= "cgroupv2",
+		.dtype		= &cgroupv2_type,
+		.len		= 8 * BITS_PER_BYTE,
+		.byteorder	= BYTEORDER_HOST_ENDIAN,
+	},
+};
+
+static void socket_expr_print(const struct expr *expr, struct output_ctx *octx)
+{
+	nft_print(octx, "socket %s", socket_templates[expr->socket.key].token);
+	if (expr->socket.key == NFT_SOCKET_CGROUPV2)
+		nft_print(octx, " level %u", expr->socket.level);
+}
+
+static bool socket_expr_cmp(const struct expr *e1, const struct expr *e2)
+{
+	return e1->socket.key == e2->socket.key &&
+	       e1->socket.level == e2->socket.level;
+}
+
+static void socket_expr_clone(struct expr *new, const struct expr *expr)
+{
+	new->socket.key = expr->socket.key;
+	new->socket.level = expr->socket.level;
+}
+
+#define NFTNL_UDATA_SOCKET_KEY 0
+#define NFTNL_UDATA_SOCKET_MAX 1
+
+static int socket_expr_build_udata(struct nftnl_udata_buf *udbuf,
+				 const struct expr *expr)
+{
+	nftnl_udata_put_u32(udbuf, NFTNL_UDATA_SOCKET_KEY, expr->socket.key);
+
+	return 0;
+}
+
+static int socket_parse_udata(const struct nftnl_udata *attr, void *data)
+{
+	const struct nftnl_udata **ud = data;
+	uint8_t type = nftnl_udata_type(attr);
+	uint8_t len = nftnl_udata_len(attr);
+
+	switch (type) {
+	case NFTNL_UDATA_SOCKET_KEY:
+		if (len != sizeof(uint32_t))
+			return -1;
+		break;
+	default:
+		return 0;
+	}
+
+	ud[type] = attr;
+	return 0;
+}
+
+static struct expr *socket_expr_parse_udata(const struct nftnl_udata *attr)
+{
+	const struct nftnl_udata *ud[NFTNL_UDATA_SOCKET_MAX + 1] = {};
+	uint32_t key;
+	int err;
+
+	err = nftnl_udata_parse(nftnl_udata_get(attr), nftnl_udata_len(attr),
+				socket_parse_udata, ud);
+	if (err < 0)
+		return NULL;
+
+	if (!ud[NFTNL_UDATA_SOCKET_KEY])
+		return NULL;
+
+	key = nftnl_udata_get_u32(ud[NFTNL_UDATA_SOCKET_KEY]);
+
+	return socket_expr_alloc(&internal_location, key, 0);
+}
+
+const struct expr_ops socket_expr_ops = {
+	.type		= EXPR_SOCKET,
+	.name		= "socket",
+	.print		= socket_expr_print,
+	.json		= socket_expr_json,
+	.cmp		= socket_expr_cmp,
+	.clone		= socket_expr_clone,
+	.build_udata	= socket_expr_build_udata,
+	.parse_udata	= socket_expr_parse_udata,
+};
+
+struct expr *socket_expr_alloc(const struct location *loc,
+			       enum nft_socket_keys key, uint32_t level)
+{
+	const struct socket_template *tmpl = &socket_templates[key];
+	struct expr *expr;
+
+	expr = expr_alloc(loc, EXPR_SOCKET, tmpl->dtype,
+			  tmpl->byteorder, tmpl->len);
+	expr->socket.key = key;
+	expr->socket.level = level;
+
+	return expr;
+}