2 * Copyright (c) 2015 Nicira, Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
17 #ifndef TUN_METADATA_H
18 #define TUN_METADATA_H 1
22 #include "dynamic-string.h"
25 #include "openflow/openflow.h"
30 struct ofputil_geneve_table_mod;
31 struct ofputil_geneve_table_reply;
35 #define TUN_METADATA_NUM_OPTS 64
36 #define TUN_METADATA_TOT_OPT_SIZE 256
38 /* Tunnel option data, plus metadata to aid in their interpretation.
40 * 'opt_map' is indexed by type, that is, by the <i> in TUN_METADATA<i>, so
41 * that e.g. TUN_METADATA5 is present if 'opt_map & (1ULL << 5)' is nonzero.
42 * The actual data for TUN_METADATA5, if present, might be anywhere in 'opts'
43 * (not necessarily even contiguous), and finding it requires referring to
46 uint64_t opt_map; /* 1-bit for each present TLV. */
47 uint8_t opts[TUN_METADATA_TOT_OPT_SIZE]; /* Values from tunnel TLVs. */
48 struct tun_table *tab; /* Types & lengths for 'opts' and 'opt_map'. */
49 uint8_t pad[sizeof(uint64_t) - sizeof(struct tun_table *)]; /* Make 8 bytes */
51 BUILD_ASSERT_DECL(sizeof(((struct tun_metadata *)0)->opt_map) * 8 >=
52 TUN_METADATA_NUM_OPTS);
54 /* The location of an option can be stored either as a single offset/len
55 * pair (hopefully) or if the address space is fragmented then it is a
56 * linked list of these blocks. */
57 struct tun_metadata_loc_chain {
58 struct tun_metadata_loc_chain *next;
59 uint8_t offset; /* In bytes, from start of 'opts', multiple of 4. */
60 uint8_t len; /* In bytes, multiple of 4. */
63 struct tun_metadata_loc {
64 int len; /* Sum of 'len' over elements in chain. */
65 struct tun_metadata_loc_chain c;
68 /* Allocation of options inside struct match. This is important if we don't
69 * have access to a global allocation table - either because there isn't one
70 * (ovs-ofctl) or if we need to keep the allocation outside of packet
71 * processing context (Packet-In). These structures never have dynamically
72 * allocated memory because the address space is never fragmented. */
73 struct tun_metadata_allocation {
74 struct tun_metadata_loc loc[TUN_METADATA_NUM_OPTS];
75 uint8_t alloc_offset; /* Byte offset into 'opts', multiple of 4. */
76 bool valid; /* Set to true after any allocation occurs. */
79 void tun_metadata_init(void);
81 enum ofperr tun_metadata_table_mod(struct ofputil_geneve_table_mod *);
82 void tun_metadata_table_request(struct ofputil_geneve_table_reply *);
84 void tun_metadata_read(const struct tun_metadata *,
85 const struct mf_field *, union mf_value *);
86 void tun_metadata_write(struct tun_metadata *,
87 const struct mf_field *, const union mf_value *);
88 void tun_metadata_set_match(const struct mf_field *,
89 const union mf_value *value,
90 const union mf_value *mask, struct match *);
91 void tun_metadata_get_fmd(const struct tun_metadata *,
92 struct match *flow_metadata);
94 int tun_metadata_from_geneve_nlattr(const struct nlattr *attr,
95 const struct nlattr *flow_attrs,
97 const struct tun_metadata *flow_metadata,
98 struct tun_metadata *metadata);
99 int tun_metadata_from_geneve_header(const struct geneve_opt *, int opt_len,
100 struct tun_metadata *metadata);
102 void tun_metadata_to_geneve_nlattr_flow(const struct tun_metadata *flow,
104 void tun_metadata_to_geneve_nlattr_mask(const struct ofpbuf *key,
105 const struct tun_metadata *mask,
106 const struct tun_metadata *flow,
108 int tun_metadata_to_geneve_header(const struct tun_metadata *flow,
109 struct geneve_opt *, bool *crit_opt);
111 void tun_metadata_to_nx_match(struct ofpbuf *b, enum ofp_version oxm,
112 const struct match *);
113 void tun_metadata_match_format(struct ds *, const struct match *);
115 #endif /* tun-metadata.h */