FD.io VPP  v19.04.1-1-ge4a0f9f
Vector Packet Processing
edit.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  * pg_edit.c: packet generator edits
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 <vlib/vlib.h>
41 #include <vnet/pg/pg.h>
42 
43 static void
44 pg_edit_set_value_helper (pg_edit_t * e, u64 value, u8 * result)
45 {
46  int i, j, n_bits_left;
47  u8 *v, tmp[8];
48 
49  v = tmp;
50 
51  n_bits_left = e->n_bits;
52  i = 0;
53  j = e->lsb_bit_offset % BITS (v[0]);
54 
55  if (n_bits_left > 0 && j != 0)
56  {
57  v[i] = (value & 0xff) << j;
58  value >>= BITS (v[0]) - j;
59  n_bits_left -= BITS (v[0]) - j;
60  i += 1;
61  }
62 
63  while (n_bits_left > 0)
64  {
65  v[i] = value & 0xff;
66  value >>= 8;
67  n_bits_left -= 8;
68  i += 1;
69  }
70 
71  /* Convert to network byte order. */
72  for (j = 0; j < i; j++)
73  result[j] = v[i - 1 - j];
74 }
75 
76 void
77 pg_edit_set_value (pg_edit_t * e, int hi_or_lo, u64 value)
78 {
79  pg_edit_alloc_value (e, hi_or_lo);
80  pg_edit_set_value_helper (e, value, e->values[hi_or_lo]);
81 }
82 
83 /* Parse an int either %d or 0x%x into network byte order. */
84 uword
85 unformat_pg_number (unformat_input_t * input, va_list * args)
86 {
87  u8 *result = va_arg (*args, u8 *);
88  pg_edit_t *e = va_arg (*args, pg_edit_t *);
89  u64 value;
90 
91  ASSERT (BITS (value) >= e->n_bits);
92 
93  if (!unformat (input, "0x%X", sizeof (value), &value)
94  && !unformat (input, "%D", sizeof (value), &value))
95  return 0;
96 
97  /* Number given does not fit into bit field. */
98  if (e->n_bits < 64 && value >= (u64) 1 << (u64) e->n_bits)
99  return 0;
100 
101  pg_edit_set_value_helper (e, value, result);
102  return 1;
103 }
104 
105 uword
106 unformat_pg_edit (unformat_input_t * input, va_list * args)
107 {
108  unformat_function_t *f = va_arg (*args, unformat_function_t *);
109  pg_edit_t *e = va_arg (*args, pg_edit_t *);
110 
112  if (!unformat_user (input, f, e->values[PG_EDIT_LO], e))
113  return 0;
114 
116  if (unformat (input, "-%U", f, e->values[PG_EDIT_HI], e))
117  e->type = PG_EDIT_INCREMENT;
118  else if (unformat (input, "+%U", f, e->values[PG_EDIT_HI], e))
119  e->type = PG_EDIT_RANDOM;
120  else
121  e->type = PG_EDIT_FIXED;
122 
123  return 1;
124 }
125 
126 uword
127 unformat_pg_payload (unformat_input_t * input, va_list * args)
128 {
129  pg_stream_t *s = va_arg (*args, pg_stream_t *);
131  pg_edit_t *e;
132  u32 i, node_index, len, max_len;
133  u8 *v;
134 
135  v = 0;
136 
137  if (unformat (input, "incrementing %d", &len))
138  {
139  vec_resize (v, len);
140  for (i = 0; i < len; i++)
141  v[i] = i % len;
142  }
143  else if (unformat (input, "hex 0x%U", unformat_hex_string, &v))
144  ;
145  else if (unformat (input, "%U", unformat_vlib_node, vm, &node_index))
146  {
147  pg_node_t *pn = pg_get_node (node_index);
148  if (!pn->unformat_edit)
149  return 0;
150  return unformat (input, "%U", pn->unformat_edit, s);
151  }
152 
153  else
154  return 0;
155 
156  /* Length not including this payload. */
157  max_len = pg_edit_group_n_bytes (s, 0);
158 
159  if (max_len >= s->max_packet_bytes)
160  {
161  /* no payload */
162  len = 0;
163  }
164  else
165  {
166  /* make a bigger v to hold the data */
167  len = s->max_packet_bytes - max_len;
168  }
169 
170  vec_resize (v, len);
171 
172  e = pg_create_edit_group (s, sizeof (e[0]), len, 0);
173 
174  e->type = PG_EDIT_FIXED;
175  e->n_bits = len * BITS (v[0]);
176 
177  /* Least significant bit is at end of bitstream, since everything is always bigendian. */
178  e->lsb_bit_offset = len > 0 ? e->n_bits - BITS (v[0]) : 0;
179 
180  e->values[PG_EDIT_LO] = v;
181 
182  return 1;
183 }
184 
185 /*
186  * fd.io coding-style-patch-verification: ON
187  *
188  * Local Variables:
189  * eval: (c-set-style "gnu")
190  * End:
191  */
Definition: edit.h:64
uword( unformat_function_t)(unformat_input_t *input, va_list *args)
Definition: format.h:232
#define PG_EDIT_LO
Definition: edit.h:83
unsigned long u64
Definition: types.h:89
unformat_function_t unformat_hex_string
Definition: format.h:288
static void pg_edit_alloc_value(pg_edit_t *e, int i)
Definition: edit.h:145
int i
uword unformat_user(unformat_input_t *input, unformat_function_t *func,...)
Definition: unformat.c:983
uword unformat_pg_edit(unformat_input_t *input, va_list *args)
Definition: edit.c:106
unsigned char u8
Definition: types.h:56
static pg_node_t * pg_get_node(uword node_index)
Definition: pg.h:357
#define PG_EDIT_HI
Definition: edit.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
i32 lsb_bit_offset
Definition: edit.h:73
#define vec_resize(V, N)
Resize a vector (no header, unspecified alignment) Add N elements to end of given vector V...
Definition: vec.h:242
unsigned int u32
Definition: types.h:88
static void * pg_create_edit_group(pg_stream_t *s, int n_edit_bytes, int n_packet_bytes, u32 *group_index)
Definition: pg.h:228
static void pg_edit_set_value_helper(pg_edit_t *e, u64 value, u8 *result)
Definition: edit.c:44
void pg_edit_set_value(pg_edit_t *e, int hi_or_lo, u64 value)
Definition: edit.c:77
u8 * values[2]
Definition: edit.h:82
struct _unformat_input_t unformat_input_t
u8 len
Definition: ip_types.api:49
u32 n_bits
Definition: edit.h:79
vlib_main_t * vm
Definition: buffer.c:312
u32 max_packet_bytes
Definition: pg.h:111
static uword pg_edit_group_n_bytes(pg_stream_t *s, u32 group_index)
Definition: pg.h:270
unformat_function_t * unformat_edit
Definition: pg.h:310
#define ASSERT(truth)
Definition: pg.h:94
static vlib_main_t * vlib_get_main(void)
Definition: global_funcs.h:23
u64 uword
Definition: types.h:112
unformat_function_t unformat_vlib_node
Definition: node_funcs.h:1177
uword unformat_pg_number(unformat_input_t *input, va_list *args)
Definition: edit.c:85
#define BITS(x)
Definition: clib.h:61
Definition: pg.h:307
uword unformat(unformat_input_t *i, const char *fmt,...)
Definition: unformat.c:972