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),
58 } __attribute__ ((packed)) vnet_rewrite_flags_t;
61 typedef CLIB_PACKED (struct {
62 /* Interface to mark re-written packets with. */
65 /* Next node to feed after packet rewrite is done. */
68 /* Number of bytes in rewrite data. */
71 /* Max packet size layer 3 (MTU) for output interface.
72 Used for MTU check after packet rewrite. */
73 u16 max_l3_packet_bytes;
75 /* Data-plane flags on the adjacency/rewrite */
76 vnet_rewrite_flags_t flags;
78 /* When dynamically writing a multicast destination L2 addresss
79 * this is the offset from the IP address at which to write in the
80 * IP->MAC address translation.
84 /* The mask to apply to the lower 4 bytes of the IP address before ORing
85 * into the destinaiton MAC address */
88 /* Rewrite string starting at end and going backwards. */
90 }) 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(total_bytes) \
114 vnet_rewrite_header_t rewrite_header; \
116 u8 rewrite_data[(total_bytes) - sizeof (vnet_rewrite_header_t)]; \
120 vnet_rewrite_clear_data_internal (vnet_rewrite_header_t * rw, int max_size)
122 /* Sanity check values carefully for this memset operation */
123 ASSERT ((max_size > 0) && (max_size < VLIB_BUFFER_PRE_DATA_SIZE));
126 memset (rw->data, 0xfe, max_size);
130 vnet_rewrite_set_data_internal (vnet_rewrite_header_t * rw,
131 int max_size, void *data, int data_bytes)
133 /* Sanity check values carefully for this memset operation */
134 ASSERT ((max_size > 0) && (max_size < VLIB_BUFFER_PRE_DATA_SIZE));
135 ASSERT ((data_bytes >= 0) && (data_bytes < max_size));
137 rw->data_bytes = data_bytes;
138 clib_memcpy (rw->data + max_size - data_bytes, data, data_bytes);
139 memset (rw->data, 0xfe, max_size - data_bytes);
142 #define vnet_rewrite_set_data(rw,data,data_bytes) \
143 vnet_rewrite_set_data_internal (&((rw).rewrite_header), \
144 sizeof ((rw).rewrite_data), \
149 vnet_rewrite_get_data_internal (vnet_rewrite_header_t * rw, int max_size)
151 ASSERT (rw->data_bytes <= max_size);
152 return rw->data + max_size - rw->data_bytes;
155 #define vnet_rewrite_get_data(rw) \
156 vnet_rewrite_get_data_internal (&((rw).rewrite_header), sizeof ((rw).rewrite_data))
159 vnet_rewrite_copy_one (vnet_rewrite_data_t * p0, vnet_rewrite_data_t * rw0,
165 void vnet_rewrite_copy_slow_path (vnet_rewrite_data_t * p0,
166 vnet_rewrite_data_t * rw0,
167 word n_left, uword most_likely_size);
170 typedef CLIB_PACKED (struct {
178 _vnet_rewrite_one_header (vnet_rewrite_header_t * h0,
179 void *packet0, int max_size, int most_likely_size)
181 vnet_rewrite_data_t *p0 = packet0;
182 vnet_rewrite_data_t *rw0 = (vnet_rewrite_data_t *) (h0->data + max_size);
185 /* 0xfefe => poisoned adjacency => crash */
186 ASSERT (h0->data_bytes != 0xfefe);
188 if (PREDICT_TRUE (h0->data_bytes == sizeof (eh_copy_t)))
191 s = (eh_copy_t *) (h0->data + max_size - sizeof (eh_copy_t));
192 d = (eh_copy_t *) (((u8 *) packet0) - sizeof (eh_copy_t));
193 clib_memcpy (d, s, sizeof (eh_copy_t));
200 if (most_likely_size > ((i)-1)*sizeof (vnet_rewrite_data_t)) \
201 vnet_rewrite_copy_one (p0, rw0, (i)); \
212 (((int) h0->data_bytes - most_likely_size) + (sizeof (rw0[0]) - 1))
213 / (int) sizeof (rw0[0]);
214 if (PREDICT_FALSE (n_left0 > 0))
215 vnet_rewrite_copy_slow_path (p0, rw0, n_left0, most_likely_size);
219 _vnet_rewrite_two_headers (vnet_rewrite_header_t * h0,
220 vnet_rewrite_header_t * h1,
222 void *packet1, int max_size, int most_likely_size)
224 vnet_rewrite_data_t *p0 = packet0;
225 vnet_rewrite_data_t *p1 = packet1;
226 vnet_rewrite_data_t *rw0 = (vnet_rewrite_data_t *) (h0->data + max_size);
227 vnet_rewrite_data_t *rw1 = (vnet_rewrite_data_t *) (h1->data + max_size);
228 word n_left0, n_left1;
231 /* 0xfefe => poisoned adjacency => crash */
232 ASSERT (h0->data_bytes != 0xfefe);
233 ASSERT (h1->data_bytes != 0xfefe);
235 /* Arithmetic calculation: bytes0 == bytes1 == 14 */
236 slow_path = h0->data_bytes ^ h1->data_bytes;
237 slow_path += h0->data_bytes ^ sizeof (eh_copy_t);
239 if (PREDICT_TRUE (slow_path == 0))
241 eh_copy_t *s0, *d0, *s1, *d1;
242 s0 = (eh_copy_t *) (h0->data + max_size - sizeof (eh_copy_t));
243 d0 = (eh_copy_t *) (((u8 *) packet0) - sizeof (eh_copy_t));
244 clib_memcpy (d0, s0, sizeof (eh_copy_t));
245 s1 = (eh_copy_t *) (h1->data + max_size - sizeof (eh_copy_t));
246 d1 = (eh_copy_t *) (((u8 *) packet1) - sizeof (eh_copy_t));
247 clib_memcpy (d1, s1, sizeof (eh_copy_t));
253 if (most_likely_size > ((i)-1)*sizeof (vnet_rewrite_data_t)) \
255 vnet_rewrite_copy_one (p0, rw0, (i)); \
256 vnet_rewrite_copy_one (p1, rw1, (i)); \
268 (((int) h0->data_bytes - most_likely_size) + (sizeof (rw0[0]) - 1))
269 / (int) sizeof (rw0[0]);
271 (((int) h1->data_bytes - most_likely_size) + (sizeof (rw1[0]) - 1))
272 / (int) sizeof (rw1[0]);
274 if (PREDICT_FALSE (n_left0 > 0 || n_left1 > 0))
276 vnet_rewrite_copy_slow_path (p0, rw0, n_left0, most_likely_size);
277 vnet_rewrite_copy_slow_path (p1, rw1, n_left1, most_likely_size);
281 #define vnet_rewrite_one_header(rw0,p0,most_likely_size) \
282 _vnet_rewrite_one_header (&((rw0).rewrite_header), (p0), \
283 sizeof ((rw0).rewrite_data), \
286 #define vnet_rewrite_two_headers(rw0,rw1,p0,p1,most_likely_size) \
287 _vnet_rewrite_two_headers (&((rw0).rewrite_header), &((rw1).rewrite_header), \
289 sizeof ((rw0).rewrite_data), \
293 _vnet_fixup_one_header (vnet_rewrite_header_t * h0,
294 u8 * addr, u32 addr_len, u8 * packet0)
296 if (PREDICT_TRUE (h0->dst_mcast_mask))
298 /* location to write to in the packet */
299 u8 *p0 = packet0 - h0->dst_mcast_offset;
300 u32 *p1 = (u32 *) p0;
301 /* location to copy from in the L3 dest address */
302 u32 *a0 = (u32 *) (addr + addr_len - sizeof (h0->dst_mcast_mask));
304 *p1 |= (*a0 & h0->dst_mcast_mask);
308 #define vnet_fixup_one_header(rw0,addr,p0) \
309 _vnet_fixup_one_header (&((rw0).rewrite_header), \
310 (u8*)(addr), sizeof((*addr)), \
313 #define VNET_REWRITE_FOR_SW_INTERFACE_ADDRESS_BROADCAST ((void *) 0)
315 void vnet_rewrite_for_sw_interface (struct vnet_main_t *vnm,
316 vnet_link_t packet_type,
320 vnet_rewrite_header_t * rw,
321 u32 max_rewrite_bytes);
323 u32 vnet_tx_node_index_for_sw_interface (struct vnet_main_t *vnm,
326 void vnet_rewrite_init (struct vnet_main_t *vnm,
329 u32 next_node, vnet_rewrite_header_t * rw);
331 u8 *vnet_build_rewrite_for_sw_interface (struct vnet_main_t *vnm,
333 vnet_link_t packet_type,
334 const void *dst_address);
335 void vnet_update_adjacency_for_sw_interface (struct vnet_main_t *vnm,
336 u32 sw_if_index, u32 ai);
338 format_function_t format_vnet_rewrite;
340 serialize_function_t serialize_vnet_rewrite, unserialize_vnet_rewrite;
342 #endif /* included_vnet_rewrite_h */
345 * fd.io coding-style-patch-verification: ON
348 * eval: (c-set-style "gnu")