2 * Copyright (c) 2015 Cisco and/or its affiliates.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at:
7 * http://www.apache.org/licenses/LICENSE-2.0
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
16 * rewrite.h: packet rewrite
18 * Copyright (c) 2008 Eliot Dresselhaus
20 * Permission is hereby granted, free of charge, to any person obtaining
21 * a copy of this software and associated documentation files (the
22 * "Software"), to deal in the Software without restriction, including
23 * without limitation the rights to use, copy, modify, merge, publish,
24 * distribute, sublicense, and/or sell copies of the Software, and to
25 * permit persons to whom the Software is furnished to do so, subject to
26 * the following conditions:
28 * The above copyright notice and this permission notice shall be
29 * included in all copies or substantial portions of the Software.
31 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
32 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
33 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
34 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
35 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
36 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
37 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
40 #ifndef included_vnet_rewrite_h
41 #define included_vnet_rewrite_h
43 #include <vlib/vlib.h>
44 #include <vnet/l3_types.h>
46 /* Consider using vector types for speed? */
47 typedef uword vnet_rewrite_data_t;
50 * Flags associated with the rewrite/adjacency
52 typedef enum vnet_rewrite_flags_t_
55 * This adjacency/interface has output features configured
57 VNET_REWRITE_HAS_FEATURES = (1 << 0),
60 * this adj performs IP4 over IP4 fixup
62 VNET_REWRITE_FIXUP_IP4_O_4 = (1 << 1),
63 } __attribute__ ((packed)) vnet_rewrite_flags_t;
65 typedef struct vnet_rewrite_header_t_
67 /* Interface to mark re-written packets with. */
70 /* Next node to feed after packet rewrite is done. */
73 /* Number of bytes in rewrite data. */
76 /* Max packet size layer 3 (MTU) for output interface.
77 Used for MTU check after packet rewrite. */
78 u16 max_l3_packet_bytes;
80 /* Data-plane flags on the adjacency/rewrite */
81 vnet_rewrite_flags_t flags;
83 /* When dynamically writing a multicast destination L2 addresss
84 * this is the offset from the IP address at which to write in the
85 * IP->MAC address translation.
89 /* Rewrite string starting at end and going backwards. */
91 } __clib_packed vnet_rewrite_header_t;
94 * At 16 bytes of rewrite herader we have enought space left for a IPv6
95 * (40 bytes) + LISP-GPE (8 bytes) in the cache line
97 STATIC_ASSERT (sizeof (vnet_rewrite_header_t) <= 16,
98 "Rewrite header too big");
101 Helper macro for declaring rewrite string w/ given max-size.
108 // Total adjacency is 64 bytes.
109 vnet_rewrite_declare(64 - 2*sizeof(int)) rw;
112 #define VNET_DECLARE_REWRITE \
115 vnet_rewrite_header_t rewrite_header; \
117 u8 rewrite_data[(VNET_REWRITE_TOTAL_BYTES) - \
118 sizeof (vnet_rewrite_header_t)]; \
121 typedef struct __rewrite_unused_t__
123 VNET_DECLARE_REWRITE;
124 } __rewrite_unused_t;
126 STATIC_ASSERT_SIZEOF (__rewrite_unused_t, 128);
129 vnet_rewrite_clear_data_internal (vnet_rewrite_header_t * rw, int max_size)
131 /* Sanity check values carefully for this clib_memset operation */
132 ASSERT ((max_size > 0) && (max_size < VLIB_BUFFER_PRE_DATA_SIZE));
135 clib_memset (rw->data, 0xfe, max_size);
139 vnet_rewrite_set_data_internal (vnet_rewrite_header_t * rw,
140 int max_size, void *data, int data_bytes)
142 /* Sanity check values carefully for this clib_memset operation */
143 ASSERT ((max_size > 0) && (max_size < VLIB_BUFFER_PRE_DATA_SIZE));
144 ASSERT ((data_bytes >= 0) && (data_bytes < max_size));
146 rw->data_bytes = data_bytes;
147 clib_memcpy_fast (rw->data, data, data_bytes);
148 clib_memset (rw->data + data_bytes, 0xfe, max_size - data_bytes);
151 #define vnet_rewrite_set_data(rw,data,data_bytes) \
152 vnet_rewrite_set_data_internal (&((rw).rewrite_header), \
153 sizeof ((rw).rewrite_data), \
158 vnet_rewrite_get_data_internal (vnet_rewrite_header_t * rw, int max_size)
160 ASSERT (rw->data_bytes <= max_size);
164 #define vnet_rewrite_get_data(rw) \
165 vnet_rewrite_get_data_internal (&((rw).rewrite_header), sizeof ((rw).rewrite_data))
168 _vnet_rewrite_one_header (const vnet_rewrite_header_t * h0,
169 void *packet0, int most_likely_size)
171 /* 0xfefe => poisoned adjacency => crash */
172 ASSERT (h0->data_bytes != 0xfefe);
173 if (PREDICT_TRUE (most_likely_size == h0->data_bytes))
175 clib_memcpy_fast ((u8 *) packet0 - most_likely_size,
176 h0->data, most_likely_size);
180 clib_memcpy_fast ((u8 *) packet0 - h0->data_bytes,
181 h0->data, h0->data_bytes);
186 _vnet_rewrite_two_headers (const vnet_rewrite_header_t * h0,
187 const vnet_rewrite_header_t * h1,
188 void *packet0, void *packet1, int most_likely_size)
190 /* 0xfefe => poisoned adjacency => crash */
191 ASSERT (h0->data_bytes != 0xfefe);
192 ASSERT (h1->data_bytes != 0xfefe);
194 (most_likely_size == h0->data_bytes
195 && most_likely_size == h1->data_bytes))
197 clib_memcpy_fast ((u8 *) packet0 - most_likely_size,
198 h0->data, most_likely_size);
199 clib_memcpy_fast ((u8 *) packet1 - most_likely_size,
200 h1->data, most_likely_size);
204 clib_memcpy_fast ((u8 *) packet0 - h0->data_bytes,
205 h0->data, h0->data_bytes);
206 clib_memcpy_fast ((u8 *) packet1 - h1->data_bytes,
207 h1->data, h1->data_bytes);
211 #define vnet_rewrite_one_header(rw0,p0,most_likely_size) \
212 _vnet_rewrite_one_header (&((rw0).rewrite_header), (p0), \
215 #define vnet_rewrite_two_headers(rw0,rw1,p0,p1,most_likely_size) \
216 _vnet_rewrite_two_headers (&((rw0).rewrite_header), &((rw1).rewrite_header), \
221 vnet_ip_mcast_fixup_header (u32 dst_mcast_mask,
222 u32 dst_mcast_offset, u32 * addr, u8 * packet0)
224 if (PREDICT_TRUE (0 != dst_mcast_offset))
226 /* location to write to in the packet */
227 u8 *p0 = packet0 - dst_mcast_offset;
228 u32 *p1 = (u32 *) p0;
230 *p1 |= (*addr & dst_mcast_mask);
234 #define VNET_REWRITE_FOR_SW_INTERFACE_ADDRESS_BROADCAST ((void *) 0)
236 void vnet_rewrite_for_sw_interface (struct vnet_main_t *vnm,
237 vnet_link_t packet_type,
241 vnet_rewrite_header_t * rw,
242 u32 max_rewrite_bytes);
244 u32 vnet_tx_node_index_for_sw_interface (struct vnet_main_t *vnm,
247 void vnet_rewrite_init (struct vnet_main_t *vnm,
251 u32 next_node, vnet_rewrite_header_t * rw);
253 void vnet_rewrite_update_mtu (struct vnet_main_t *vnm,
254 vnet_link_t linkt, vnet_rewrite_header_t * rw);
256 u8 *vnet_build_rewrite_for_sw_interface (struct vnet_main_t *vnm,
258 vnet_link_t packet_type,
259 const void *dst_address);
260 void vnet_update_adjacency_for_sw_interface (struct vnet_main_t *vnm,
261 u32 sw_if_index, u32 ai);
263 format_function_t format_vnet_rewrite;
265 serialize_function_t serialize_vnet_rewrite, unserialize_vnet_rewrite;
267 #endif /* included_vnet_rewrite_h */
270 * fd.io coding-style-patch-verification: ON
273 * eval: (c-set-style "gnu")