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
43static void
44pg_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
76void
77pg_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. */
84uword
85unformat_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
105uword
106unformat_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
111  pg_edit_alloc_value (e, PG_EDIT_LO);
112  if (!unformat_user (input, f, e->values[PG_EDIT_LO], e))
113    return 0;
114
115  pg_edit_alloc_value (e, PG_EDIT_HI);
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
126uword
127unformat_pg_payload (unformat_input_t * input, va_list * args)
128{
129  pg_stream_t *s = va_arg (*args, pg_stream_t *);
130  vlib_main_t *vm = vlib_get_main ();
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 */
192