nftables/0032-src-store-expr-not-dtype-to-track-data-in-sets.patch

From 19da892698f1dce2125a796ad86239711896978f Mon Sep 17 00:00:00 2001
From: Phil Sutter <psutter@redhat.com>
Date: Mon, 7 Dec 2020 18:25:20 +0100
Subject: [PATCH] src: store expr, not dtype to track data in sets

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1877022
Upstream Status: nftables commit 343a51702656a

commit 343a51702656a6476e37cfb84609a82155c7fc5e
Author: Florian Westphal <fw@strlen.de>
Date:   Tue Jul 16 19:03:55 2019 +0200

    src: store expr, not dtype to track data in sets

    This will be needed once we add support for the 'typeof' keyword to
    handle maps that could e.g. store 'ct helper' "type" values.

    Instead of:

    set foo {
            type ipv4_addr . mark;

    this would allow

    set foo {
            typeof(ip saddr) . typeof(ct mark);

    (exact syntax TBD).

    This would be needed to allow sets that store variable-sized data types
    (string, integer and the like) that can't be used at at the moment.

    Adding special data types for everything is problematic due to the
    large amount of different types needed.

    For anonymous sets, e.g. "string" can be used because the needed size can
    be inferred from the statement, e.g.  'osf name { "Windows", "Linux }',
    but in case of named sets that won't work because 'type string' lacks the
    context needed to derive the size information.

    With 'typeof(osf name)' the context is there, but at the moment it won't
    help because the expression is discarded instantly and only the data
    type is retained.

    Signed-off-by: Florian Westphal <fw@strlen.de>
---
 include/datatype.h |  1 -
 include/netlink.h  |  1 -
 include/rule.h     |  6 ++---
 src/datatype.c     |  5 ----
 src/evaluate.c     | 58 ++++++++++++++++++++++++++++++++--------------
 src/expression.c   |  2 +-
 src/json.c         |  4 ++--
 src/mnl.c          |  6 ++---
 src/monitor.c      |  2 +-
 src/netlink.c      | 32 ++++++++++++-------------
 src/parser_bison.y |  3 +--
 src/parser_json.c  |  8 +++++--
 src/rule.c         |  8 +++----
 src/segtree.c      |  8 +++++--
 14 files changed, 81 insertions(+), 63 deletions(-)

diff --git a/include/datatype.h b/include/datatype.h
index 49b8f60..04b4892 100644
--- a/include/datatype.h
+++ b/include/datatype.h
@@ -293,7 +293,6 @@ concat_subtype_lookup(uint32_t type, unsigned int n)
 
 extern const struct datatype *
 set_datatype_alloc(const struct datatype *orig_dtype, unsigned int byteorder);
-extern void set_datatype_destroy(const struct datatype *dtype);
 
 extern void time_print(uint64_t msec, struct output_ctx *octx);
 extern struct error_record *time_parse(const struct location *loc,
diff --git a/include/netlink.h b/include/netlink.h
index e694171..88d12ba 100644
--- a/include/netlink.h
+++ b/include/netlink.h
@@ -189,6 +189,5 @@ int netlink_events_trace_cb(const struct nlmsghdr *nlh, int type,
 			    struct netlink_mon_handler *monh);
 
 enum nft_data_types dtype_map_to_kernel(const struct datatype *dtype);
-const struct datatype *dtype_map_from_kernel(enum nft_data_types type);
 
 #endif /* NFTABLES_NETLINK_H */
diff --git a/include/rule.h b/include/rule.h
index 626973e..3637462 100644
--- a/include/rule.h
+++ b/include/rule.h
@@ -283,8 +283,7 @@ extern struct rule *rule_lookup_by_index(const struct chain *chain,
  * @gc_int:	garbage collection interval
  * @timeout:	default timeout value
  * @key:	key expression (data type, length))
- * @datatype:	mapping data type
- * @datalen:	mapping data len
+ * @data:	mapping data expression
  * @objtype:	mapping object type
  * @init:	initializer
  * @rg_cache:	cached range element (left)
@@ -303,8 +302,7 @@ struct set {
 	uint32_t		gc_int;
 	uint64_t		timeout;
 	struct expr		*key;
-	const struct datatype	*datatype;
-	unsigned int		datalen;
+	struct expr		*data;
 	uint32_t		objtype;
 	struct expr		*init;
 	struct expr		*rg_cache;
diff --git a/src/datatype.c b/src/datatype.c
index b9e167e..189e1b4 100644
--- a/src/datatype.c
+++ b/src/datatype.c
@@ -1190,11 +1190,6 @@ const struct datatype *set_datatype_alloc(const struct datatype *orig_dtype,
 	return dtype;
 }
 
-void set_datatype_destroy(const struct datatype *dtype)
-{
-	datatype_free(dtype);
-}
-
 static struct error_record *time_unit_parse(const struct location *loc,
 					    const char *str, uint64_t *unit)
 {
diff --git a/src/evaluate.c b/src/evaluate.c
index f66251b..578dcae 100644
--- a/src/evaluate.c
+++ b/src/evaluate.c
@@ -1383,6 +1383,7 @@ static int expr_evaluate_map(struct eval_ctx *ctx, struct expr **expr)
 {
 	struct expr_ctx ectx = ctx->ectx;
 	struct expr *map = *expr, *mappings;
+	const struct datatype *dtype;
 	struct expr *key;
 
 	expr_set_context(&ctx->ectx, NULL, 0);
@@ -1405,10 +1406,14 @@ static int expr_evaluate_map(struct eval_ctx *ctx, struct expr **expr)
 		mappings = implicit_set_declaration(ctx, "__map%d",
 						    key,
 						    mappings);
-		mappings->set->datatype =
-			datatype_get(set_datatype_alloc(ectx.dtype,
-							ectx.byteorder));
-		mappings->set->datalen  = ectx.len;
+
+		dtype = set_datatype_alloc(ectx.dtype, ectx.byteorder);
+
+		mappings->set->data = constant_expr_alloc(&netlink_location,
+							  dtype, dtype->byteorder,
+							  ectx.len, NULL);
+		if (ectx.len && mappings->set->data->len != ectx.len)
+			BUG("%d vs %d\n", mappings->set->data->len, ectx.len);
 
 		map->mappings = mappings;
 
@@ -1444,7 +1449,7 @@ static int expr_evaluate_map(struct eval_ctx *ctx, struct expr **expr)
 					 map->mappings->set->key->dtype->desc,
 					 map->map->dtype->desc);
 
-	datatype_set(map, map->mappings->set->datatype);
+	datatype_set(map, map->mappings->set->data->dtype);
 	map->flags |= EXPR_F_CONSTANT;
 
 	/* Data for range lookups needs to be in big endian order */
@@ -1474,7 +1479,12 @@ static int expr_evaluate_mapping(struct eval_ctx *ctx, struct expr **expr)
 				  "Key must be a constant");
 	mapping->flags |= mapping->left->flags & EXPR_F_SINGLETON;
 
-	expr_set_context(&ctx->ectx, set->datatype, set->datalen);
+	if (set->data) {
+		expr_set_context(&ctx->ectx, set->data->dtype, set->data->len);
+	} else {
+		assert((set->flags & NFT_SET_MAP) == 0);
+	}
+
 	if (expr_evaluate(ctx, &mapping->right) < 0)
 		return -1;
 	if (!expr_is_constant(mapping->right))
@@ -2119,7 +2129,7 @@ static int stmt_evaluate_arg(struct eval_ctx *ctx, struct stmt *stmt,
 					 (*expr)->len);
 	else if ((*expr)->dtype->type != TYPE_INTEGER &&
 		 !datatype_equal((*expr)->dtype, dtype))
-		return stmt_binary_error(ctx, *expr, stmt,
+		return stmt_binary_error(ctx, *expr, stmt,		/* verdict vs invalid? */
 					 "datatype mismatch: expected %s, "
 					 "expression has type %s",
 					 dtype->desc, (*expr)->dtype->desc);
@@ -3113,9 +3123,9 @@ static int stmt_evaluate_map(struct eval_ctx *ctx, struct stmt *stmt)
 				  "Key expression comments are not supported");
 
 	if (stmt_evaluate_arg(ctx, stmt,
-			      stmt->map.set->set->datatype,
-			      stmt->map.set->set->datalen,
-			      stmt->map.set->set->datatype->byteorder,
+			      stmt->map.set->set->data->dtype,
+			      stmt->map.set->set->data->len,
+			      stmt->map.set->set->data->byteorder,
 			      &stmt->map.data->key) < 0)
 		return -1;
 	if (expr_is_constant(stmt->map.data))
@@ -3161,8 +3171,12 @@ static int stmt_evaluate_objref_map(struct eval_ctx *ctx, struct stmt *stmt)
 
 		mappings = implicit_set_declaration(ctx, "__objmap%d",
 						    key, mappings);
-		mappings->set->datatype = &string_type;
-		mappings->set->datalen  = NFT_OBJ_MAXNAMELEN * BITS_PER_BYTE;
+
+		mappings->set->data = constant_expr_alloc(&netlink_location,
+							  &string_type,
+							  BYTEORDER_HOST_ENDIAN,
+							  NFT_OBJ_MAXNAMELEN * BITS_PER_BYTE,
+							  NULL);
 		mappings->set->objtype  = stmt->objref.type;
 
 		map->mappings = mappings;
@@ -3197,7 +3211,7 @@ static int stmt_evaluate_objref_map(struct eval_ctx *ctx, struct stmt *stmt)
 					 map->mappings->set->key->dtype->desc,
 					 map->map->dtype->desc);
 
-	datatype_set(map, map->mappings->set->datatype);
+	datatype_set(map, map->mappings->set->data->dtype);
 	map->flags |= EXPR_F_CONSTANT;
 
 	/* Data for range lookups needs to be in big endian order */
@@ -3346,17 +3360,25 @@ static int set_evaluate(struct eval_ctx *ctx, struct set *set)
 	}
 
 	if (set_is_datamap(set->flags)) {
-		if (set->datatype == NULL)
+		if (set->data == NULL)
 			return set_error(ctx, set, "map definition does not "
 					 "specify mapping data type");
 
-		set->datalen = set->datatype->size;
-		if (set->datalen == 0 && set->datatype->type != TYPE_VERDICT)
+		if (set->data->len == 0 && set->data->dtype->type != TYPE_VERDICT)
 			return set_error(ctx, set, "unqualified mapping data "
 					 "type specified in map definition");
 	} else if (set_is_objmap(set->flags)) {
-		set->datatype = &string_type;
-		set->datalen  = NFT_OBJ_MAXNAMELEN * BITS_PER_BYTE;
+		if (set->data) {
+			assert(set->data->etype == EXPR_VALUE);
+			assert(set->data->dtype == &string_type);
+		}
+
+		assert(set->data == NULL);
+		set->data = constant_expr_alloc(&netlink_location, &string_type,
+						BYTEORDER_HOST_ENDIAN,
+						NFT_OBJ_MAXNAMELEN * BITS_PER_BYTE,
+						NULL);
+
 	}
 
 	ctx->set = set;
diff --git a/src/expression.c b/src/expression.c
index 5070b10..6fa2f1d 100644
--- a/src/expression.c
+++ b/src/expression.c
@@ -1010,7 +1010,7 @@ static void map_expr_print(const struct expr *expr, struct output_ctx *octx)
 {
 	expr_print(expr->map, octx);
 	if (expr->mappings->etype == EXPR_SET_REF &&
-	    expr->mappings->set->datatype->type == TYPE_VERDICT)
+	    expr->mappings->set->data->dtype->type == TYPE_VERDICT)
 		nft_print(octx, " vmap ");
 	else
 		nft_print(octx, " map ");
diff --git a/src/json.c b/src/json.c
index 3498e24..1906e7d 100644
--- a/src/json.c
+++ b/src/json.c
@@ -82,7 +82,7 @@ static json_t *set_print_json(struct output_ctx *octx, const struct set *set)
 
 	if (set_is_datamap(set->flags)) {
 		type = "map";
-		datatype_ext = set->datatype->name;
+		datatype_ext = set->data->dtype->name;
 	} else if (set_is_objmap(set->flags)) {
 		type = "map";
 		datatype_ext = obj_type_name(set->objtype);
@@ -645,7 +645,7 @@ json_t *map_expr_json(const struct expr *expr, struct output_ctx *octx)
 	const char *type = "map";
 
 	if (expr->mappings->etype == EXPR_SET_REF &&
-	    expr->mappings->set->datatype->type == TYPE_VERDICT)
+	    expr->mappings->set->data->dtype->type == TYPE_VERDICT)
 		type = "vmap";
 
 	return json_pack("{s:{s:o, s:o}}", type,
diff --git a/src/mnl.c b/src/mnl.c
index 221ee05..23341e6 100644
--- a/src/mnl.c
+++ b/src/mnl.c
@@ -839,9 +839,9 @@ int mnl_nft_set_add(struct netlink_ctx *ctx, const struct cmd *cmd,
 			  div_round_up(set->key->len, BITS_PER_BYTE));
 	if (set_is_datamap(set->flags)) {
 		nftnl_set_set_u32(nls, NFTNL_SET_DATA_TYPE,
-				  dtype_map_to_kernel(set->datatype));
+				  dtype_map_to_kernel(set->data->dtype));
 		nftnl_set_set_u32(nls, NFTNL_SET_DATA_LEN,
-				  set->datalen / BITS_PER_BYTE);
+				  set->data->len / BITS_PER_BYTE);
 	}
 	if (set_is_objmap(set->flags))
 		nftnl_set_set_u32(nls, NFTNL_SET_OBJ_TYPE, set->objtype);
@@ -873,7 +873,7 @@ int mnl_nft_set_add(struct netlink_ctx *ctx, const struct cmd *cmd,
 
 	if (set_is_datamap(set->flags) &&
 	    !nftnl_udata_put_u32(udbuf, NFTNL_UDATA_SET_DATABYTEORDER,
-				 set->datatype->byteorder))
+				 set->data->byteorder))
 		memory_allocation_error();
 
 	if (set->automerge &&
diff --git a/src/monitor.c b/src/monitor.c
index fb803cf..7927b6f 100644
--- a/src/monitor.c
+++ b/src/monitor.c
@@ -401,7 +401,7 @@ static int netlink_events_setelem_cb(const struct nlmsghdr *nlh, int type,
 	 */
 	dummyset = set_alloc(monh->loc);
 	dummyset->key = expr_clone(set->key);
-	dummyset->datatype = set->datatype;
+	dummyset->data = set->data;
 	dummyset->flags = set->flags;
 	dummyset->init = set_expr_alloc(monh->loc, set);
 
diff --git a/src/netlink.c b/src/netlink.c
index e0ba903..64e51e5 100644
--- a/src/netlink.c
+++ b/src/netlink.c
@@ -575,7 +575,7 @@ enum nft_data_types dtype_map_to_kernel(const struct datatype *dtype)
 	}
 }
 
-const struct datatype *dtype_map_from_kernel(enum nft_data_types type)
+static const struct datatype *dtype_map_from_kernel(enum nft_data_types type)
 {
 	switch (type) {
 	case NFT_DATA_VERDICT:
@@ -622,10 +622,10 @@ struct set *netlink_delinearize_set(struct netlink_ctx *ctx,
 				    const struct nftnl_set *nls)
 {
 	const struct nftnl_udata *ud[NFTNL_UDATA_SET_MAX + 1] = {};
-	uint32_t flags, key, data, data_len, objtype = 0;
 	enum byteorder keybyteorder = BYTEORDER_INVALID;
 	enum byteorder databyteorder = BYTEORDER_INVALID;
-	const struct datatype *keytype, *datatype;
+	const struct datatype *keytype, *datatype = NULL;
+	uint32_t flags, key, objtype = 0;
 	bool automerge = false;
 	const char *udata;
 	struct set *set;
@@ -659,6 +659,8 @@ struct set *netlink_delinearize_set(struct netlink_ctx *ctx,
 
 	flags = nftnl_set_get_u32(nls, NFTNL_SET_FLAGS);
 	if (set_is_datamap(flags)) {
+		uint32_t data;
+
 		data = nftnl_set_get_u32(nls, NFTNL_SET_DATA_TYPE);
 		datatype = dtype_map_from_kernel(data);
 		if (datatype == NULL) {
@@ -667,8 +669,7 @@ struct set *netlink_delinearize_set(struct netlink_ctx *ctx,
 					 data);
 			return NULL;
 		}
-	} else
-		datatype = NULL;
+	}
 
 	if (set_is_objmap(flags)) {
 		objtype = nftnl_set_get_u32(nls, NFTNL_SET_OBJ_TYPE);
@@ -691,16 +692,13 @@ struct set *netlink_delinearize_set(struct netlink_ctx *ctx,
 
 	set->objtype = objtype;
 
+	set->data = NULL;
 	if (datatype)
-		set->datatype = datatype_get(set_datatype_alloc(datatype,
-								databyteorder));
-	else
-		set->datatype = NULL;
-
-	if (nftnl_set_is_set(nls, NFTNL_SET_DATA_LEN)) {
-		data_len = nftnl_set_get_u32(nls, NFTNL_SET_DATA_LEN);
-		set->datalen = data_len * BITS_PER_BYTE;
-	}
+		set->data = constant_expr_alloc(&netlink_location,
+						set_datatype_alloc(datatype, databyteorder),
+						databyteorder,
+						nftnl_set_get_u32(nls, NFTNL_SET_DATA_LEN) * BITS_PER_BYTE,
+						NULL);
 
 	if (nftnl_set_is_set(nls, NFTNL_SET_TIMEOUT))
 		set->timeout = nftnl_set_get_u64(nls, NFTNL_SET_TIMEOUT);
@@ -897,10 +895,10 @@ key_end:
 			goto out;
 
 		data = netlink_alloc_data(&netlink_location, &nld,
-					  set->datatype->type == TYPE_VERDICT ?
+					  set->data->dtype->type == TYPE_VERDICT ?
 					  NFT_REG_VERDICT : NFT_REG_1);
-		datatype_set(data, set->datatype);
-		data->byteorder = set->datatype->byteorder;
+		datatype_set(data, set->data->dtype);
+		data->byteorder = set->data->byteorder;
 		if (data->byteorder == BYTEORDER_HOST_ENDIAN)
 			mpz_switch_byteorder(data->value, data->len / BITS_PER_BYTE);
 
diff --git a/src/parser_bison.y b/src/parser_bison.y
index ea83f52..4cca31b 100644
--- a/src/parser_bison.y
+++ b/src/parser_bison.y
@@ -1749,9 +1749,8 @@ map_block		:	/* empty */	{ $$ = $<set>-1; }
 						stmt_separator
 			{
 				$1->key = $3;
-				$1->datatype = $5->dtype;
+				$1->data = $5;
 
-				expr_free($5);
 				$1->flags |= NFT_SET_MAP;
 				$$ = $1;
 			}
diff --git a/src/parser_json.c b/src/parser_json.c
index ce8e566..ddc694f 100644
--- a/src/parser_json.c
+++ b/src/parser_json.c
@@ -2833,11 +2833,15 @@ static struct cmd *json_parse_cmd_add_set(struct json_ctx *ctx, json_t *root,
 	}
 
 	if (!json_unpack(root, "{s:s}", "map", &dtype_ext)) {
+		const struct datatype *dtype;
+
 		set->objtype = string_to_nft_object(dtype_ext);
 		if (set->objtype) {
 			set->flags |= NFT_SET_OBJECT;
-		} else if (datatype_lookup_byname(dtype_ext)) {
-			set->datatype = datatype_lookup_byname(dtype_ext);
+		} else if ((dtype = datatype_lookup_byname(dtype_ext))) {
+			set->data = constant_expr_alloc(&netlink_location,
+							dtype, dtype->byteorder,
+							dtype->size, NULL);
 			set->flags |= NFT_SET_MAP;
 		} else {
 			json_error(ctx, "Invalid map type '%s'.", dtype_ext);
diff --git a/src/rule.c b/src/rule.c
index e18237b..f7d888b 100644
--- a/src/rule.c
+++ b/src/rule.c
@@ -332,8 +332,8 @@ struct set *set_clone(const struct set *set)
 	new_set->gc_int		= set->gc_int;
 	new_set->timeout	= set->timeout;
 	new_set->key		= expr_clone(set->key);
-	new_set->datatype	= datatype_get(set->datatype);
-	new_set->datalen	= set->datalen;
+	if (set->data)
+		new_set->data	= expr_clone(set->data);
 	new_set->objtype	= set->objtype;
 	new_set->policy		= set->policy;
 	new_set->automerge	= set->automerge;
@@ -356,7 +356,7 @@ void set_free(struct set *set)
 		expr_free(set->init);
 	handle_free(&set->handle);
 	expr_free(set->key);
-	set_datatype_destroy(set->datatype);
+	expr_free(set->data);
 	xfree(set);
 }
 
@@ -469,7 +469,7 @@ static void set_print_declaration(const struct set *set,
 	nft_print(octx, "%s%stype %s",
 		  opts->tab, opts->tab, set->key->dtype->name);
 	if (set_is_datamap(set->flags))
-		nft_print(octx, " : %s", set->datatype->name);
+		nft_print(octx, " : %s", set->data->dtype->name);
 	else if (set_is_objmap(set->flags))
 		nft_print(octx, " : %s", obj_type_name(set->objtype));
 
diff --git a/src/segtree.c b/src/segtree.c
index 073c6ec..d6e3ce2 100644
--- a/src/segtree.c
+++ b/src/segtree.c
@@ -79,8 +79,12 @@ static void seg_tree_init(struct seg_tree *tree, const struct set *set,
 	tree->root	= RB_ROOT;
 	tree->keytype	= set->key->dtype;
 	tree->keylen	= set->key->len;
-	tree->datatype	= set->datatype;
-	tree->datalen	= set->datalen;
+	tree->datatype	= NULL;
+	tree->datalen	= 0;
+	if (set->data) {
+		tree->datatype	= set->data->dtype;
+		tree->datalen	= set->data->len;
+	}
 	tree->byteorder	= first->byteorder;
 	tree->debug_mask = debug_mask;
 }
-- 
2.31.1