FD.io VPP  v17.01.1-3-gc6833f8
Vector Packet Processing
udp_pg.c
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1 /*
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:
6  *
7  * http://www.apache.org/licenses/LICENSE-2.0
8  *
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.
14  */
15 /*
16  * ip/udp_pg: UDP packet-generator interface
17  *
18  * Copyright (c) 2008 Eliot Dresselhaus
19  *
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:
27  *
28  * The above copyright notice and this permission notice shall be
29  * included in all copies or substantial portions of the Software.
30  *
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.
38  */
39 
40 #include <vnet/pg/pg.h>
41 #include <vnet/ip/ip.h> /* for unformat_udp_udp_port */
42 
43 #define UDP_PG_EDIT_LENGTH (1 << 0)
44 #define UDP_PG_EDIT_CHECKSUM (1 << 1)
45 
46 always_inline void
48  pg_stream_t * s,
49  pg_edit_group_t * g,
50  u32 * packets, u32 n_packets, u32 flags)
51 {
52  vlib_main_t *vm = vlib_get_main ();
53  u32 ip_offset, udp_offset;
54 
55  udp_offset = g->start_byte_offset;
56  ip_offset = (g - 1)->start_byte_offset;
57 
58  while (n_packets >= 1)
59  {
60  vlib_buffer_t *p0;
61  ip4_header_t *ip0;
62  udp_header_t *udp0;
63  u32 udp_len0;
64 
65  p0 = vlib_get_buffer (vm, packets[0]);
66  n_packets -= 1;
67  packets += 1;
68 
69  ip0 = (void *) (p0->data + ip_offset);
70  udp0 = (void *) (p0->data + udp_offset);
71  udp_len0 = clib_net_to_host_u16 (ip0->length) - sizeof (ip0[0]);
72 
73  if (flags & UDP_PG_EDIT_LENGTH)
74  udp0->length =
75  clib_net_to_host_u16 (vlib_buffer_length_in_chain (vm, p0)
76  - ip_offset);
77 
78  /* Initialize checksum with header. */
79  if (flags & UDP_PG_EDIT_CHECKSUM)
80  {
81  ip_csum_t sum0;
82 
83  sum0 = clib_mem_unaligned (&ip0->src_address, u64);
84 
85  sum0 = ip_csum_with_carry
86  (sum0, clib_host_to_net_u32 (udp_len0 + (ip0->protocol << 16)));
87 
88  /* Invalidate possibly old checksum. */
89  udp0->checksum = 0;
90 
91  sum0 =
92  ip_incremental_checksum_buffer (vm, p0, udp_offset, udp_len0,
93  sum0);
94 
95  sum0 = ~ip_csum_fold (sum0);
96 
97  /* Zero checksum means checksumming disabled. */
98  sum0 = sum0 != 0 ? sum0 : 0xffff;
99 
100  udp0->checksum = sum0;
101  }
102  }
103 }
104 
105 static void
107  pg_stream_t * s,
108  pg_edit_group_t * g, u32 * packets, u32 n_packets)
109 {
110  switch (g->edit_function_opaque)
111  {
112  case UDP_PG_EDIT_LENGTH:
113  udp_pg_edit_function_inline (pg, s, g, packets, n_packets,
115  break;
116 
118  udp_pg_edit_function_inline (pg, s, g, packets, n_packets,
120  break;
121 
123  udp_pg_edit_function_inline (pg, s, g, packets, n_packets,
125  break;
126 
127  default:
128  ASSERT (0);
129  break;
130  }
131 }
132 
133 typedef struct
134 {
135  pg_edit_t src_port, dst_port;
139 
140 static inline void
142 {
143  /* Initialize fields that are not bit fields in the IP header. */
144 #define _(f) pg_edit_init (&p->f, udp_header_t, f);
145  _(src_port);
146  _(dst_port);
147  _(length);
148  _(checksum);
149 #undef _
150 }
151 
152 uword
153 unformat_pg_udp_header (unformat_input_t * input, va_list * args)
154 {
155  pg_stream_t *s = va_arg (*args, pg_stream_t *);
156  pg_udp_header_t *p;
157  u32 group_index;
158 
159  p = pg_create_edit_group (s, sizeof (p[0]), sizeof (udp_header_t),
160  &group_index);
161  pg_udp_header_init (p);
162 
163  /* Defaults. */
166 
167  if (!unformat (input, "UDP: %U -> %U",
171  goto error;
172 
173  /* Parse options. */
174  while (1)
175  {
176  if (unformat (input, "length %U",
178  ;
179 
180  else if (unformat (input, "checksum %U",
182  ;
183 
184  /* Can't parse input: try next protocol level. */
185  else
186  break;
187  }
188 
189  {
190  ip_main_t *im = &ip_main;
191  u16 dst_port;
193 
194  pi = 0;
195  if (p->dst_port.type == PG_EDIT_FIXED)
196  {
197  dst_port = pg_edit_get_value (&p->dst_port, PG_EDIT_LO);
198  pi = ip_get_tcp_udp_port_info (im, dst_port);
199  }
200 
201  if (pi && pi->unformat_pg_edit
202  && unformat_user (input, pi->unformat_pg_edit, s))
203  ;
204 
205  else if (!unformat_user (input, unformat_pg_payload, s))
206  goto error;
207 
208  p = pg_get_edit_group (s, group_index);
211  {
212  pg_edit_group_t *g = pg_stream_get_group (s, group_index);
214  g->edit_function_opaque = 0;
217  if (p->length.type == PG_EDIT_UNSPECIFIED)
219  }
220 
221  return 1;
222  }
223 
224 error:
225  /* Free up any edits we may have added. */
226  pg_free_edit_group (s);
227  return 0;
228 }
229 
230 
231 /*
232  * fd.io coding-style-patch-verification: ON
233  *
234  * Local Variables:
235  * eval: (c-set-style "gnu")
236  * End:
237  */
Definition: edit.h:64
static ip_csum_t ip_incremental_checksum_buffer(vlib_main_t *vm, vlib_buffer_t *first_buffer, u32 first_buffer_offset, u32 n_bytes_to_checksum, ip_csum_t sum)
Definition: ip.h:151
#define UDP_PG_EDIT_CHECKSUM
Definition: udp_pg.c:44
#define PG_EDIT_LO
Definition: edit.h:83
uword unformat(unformat_input_t *i, char *fmt,...)
Definition: unformat.c:966
static void * pg_get_edit_group(pg_stream_t *s, u32 group_index)
Definition: pg.h:259
ip4_address_t src_address
Definition: ip4_packet.h:163
static vlib_main_t * vlib_get_main(void)
Definition: global_funcs.h:23
Definition: pg.h:310
void(* edit_function)(struct pg_main_t *pg, struct pg_stream_t *s, struct pg_edit_group_t *g, u32 *buffers, u32 n_buffers)
Definition: pg.h:73
pg_edit_t checksum
Definition: udp_pg.c:137
uword unformat_pg_edit(unformat_input_t *input, va_list *args)
Definition: edit.c:106
uword ip_csum_t
Definition: ip_packet.h:90
static ip_csum_t ip_csum_with_carry(ip_csum_t sum, ip_csum_t x)
Definition: ip_packet.h:93
Definition: ip.h:106
static uword vlib_buffer_length_in_chain(vlib_main_t *vm, vlib_buffer_t *b)
Get length in bytes of the buffer chain.
Definition: buffer_funcs.h:100
u32 start_byte_offset
Definition: pg.h:67
static pg_edit_group_t * pg_stream_get_group(pg_stream_t *s, u32 group_index)
Definition: pg.h:219
#define always_inline
Definition: clib.h:84
uword unformat_pg_payload(unformat_input_t *input, va_list *args)
Definition: edit.c:127
pg_edit_type_t type
Definition: edit.h:66
#define UDP_PG_EDIT_LENGTH
Definition: udp_pg.c:43
unsigned long u64
Definition: types.h:89
uword unformat_user(unformat_input_t *input, unformat_function_t *func,...)
Definition: unformat.c:977
static void * pg_create_edit_group(pg_stream_t *s, int n_edit_bytes, int n_packet_bytes, u32 *group_index)
Definition: pg.h:225
pg_edit_t src_port
Definition: udp_pg.c:135
static u64 pg_edit_get_value(pg_edit_t *e, int hi_or_lo)
Definition: edit.h:173
static void udp_pg_edit_function_inline(pg_main_t *pg, pg_stream_t *s, pg_edit_group_t *g, u32 *packets, u32 n_packets, u32 flags)
Definition: udp_pg.c:47
uword unformat_pg_udp_header(unformat_input_t *input, va_list *args)
Definition: udp_pg.c:153
ip_main_t ip_main
Definition: ip_init.c:42
pg_edit_t dst_port
Definition: udp_pg.c:135
static tcp_udp_port_info_t * ip_get_tcp_udp_port_info(ip_main_t *im, u32 port)
Definition: ip.h:142
#define ASSERT(truth)
unsigned int u32
Definition: types.h:88
unformat_function_t * unformat_pg_edit
Definition: ip.h:103
static void pg_udp_header_init(pg_udp_header_t *p)
Definition: udp_pg.c:141
static void pg_free_edit_group(pg_stream_t *s)
Definition: pg.h:278
uword edit_function_opaque
Definition: pg.h:79
Definition: pg.h:96
u64 uword
Definition: types.h:112
unsigned short u16
Definition: types.h:57
#define clib_mem_unaligned(pointer, type)
Definition: types.h:155
uword unformat_pg_number(unformat_input_t *input, va_list *args)
Definition: edit.c:85
u8 data[0]
Packet data.
Definition: buffer.h:158
pg_edit_t length
Definition: udp_pg.c:136
struct _unformat_input_t unformat_input_t
unformat_function_t unformat_tcp_udp_port
Definition: format.h:49
u32 flags
Definition: vhost-user.h:75
static vlib_buffer_t * vlib_get_buffer(vlib_main_t *vm, u32 buffer_index)
Translate buffer index into buffer pointer.
Definition: buffer_funcs.h:57
static void udp_pg_edit_function(pg_main_t *pg, pg_stream_t *s, pg_edit_group_t *g, u32 *packets, u32 n_packets)
Definition: udp_pg.c:106
static u16 ip_csum_fold(ip_csum_t c)
Definition: ip_packet.h:145