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.h: 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#ifndef included_packet_generator_pg_edit_h
41#define included_packet_generator_pg_edit_h
42
43#include <vppinfra/format.h>
44#include <vppinfra/vec.h>
45
46typedef enum
47{
48  /* Invalid type used to poison edits. */
49  PG_EDIT_INVALID_TYPE,
50
51  /* Value is fixed: does not change for all packets in sequence. */
52  PG_EDIT_FIXED,
53
54  /* Value v increments between low and high values v_low <= v <= v_high. */
55  PG_EDIT_INCREMENT,
56
57  /* Random value between low and high values v_low <= v <= v_high. */
58  PG_EDIT_RANDOM,
59
60  /* Unspecified value; will be specified by some edit function. */
61  PG_EDIT_UNSPECIFIED,
62} pg_edit_type_t;
63
64typedef struct
65{
66  pg_edit_type_t type;
67
68  /* Bit offset within packet where value is to be written.
69     Bits are written in network byte order: high bits first.
70     This is the bit offset of the least significant bit: i.e. the
71     highest numbered byte * 8 plus bit offset within that byte.
72     Negative offsets encode special edits. */
73  i32 lsb_bit_offset;
74
75  /* Special offset indicating this edit is for packet length. */
76#define PG_EDIT_PACKET_LENGTH (-1)
77
78  /* Number of bits in edit. */
79  u32 n_bits;
80
81  /* Low and high values for this edit.  Network byte order. */
82  u8 *values[2];
83#define PG_EDIT_LO 0
84#define PG_EDIT_HI 1
85
86  /* Last value used for increment edit type. */
87  u64 last_increment_value;
88} pg_edit_t;
89
90always_inline void
91pg_edit_free (pg_edit_t * e)
92{
93  int i;
94  for (i = 0; i < ARRAY_LEN (e->values); i++)
95    vec_free (e->values[i]);
96}
97
98#define pg_edit_init_bitfield(e,type,field,field_offset,field_n_bits)	\
99do {									\
100  u32 _bo;								\
101									\
102  ASSERT ((field_offset) < STRUCT_BITS_OF (type, field));		\
103									\
104  /* Start byte offset. */						\
105  _bo = STRUCT_OFFSET_OF (type, field);					\
106									\
107  /* Adjust for big endian byte order. */				\
108  _bo += ((STRUCT_BITS_OF (type, field)					\
109	   - (field_offset) - 1) / BITS (u8));				\
110									\
111  (e)->lsb_bit_offset = _bo * BITS (u8) + ((field_offset) % BITS (u8));	\
112  (e)->n_bits = (field_n_bits);						\
113} while (0)
114
115/* Initialize edit for byte aligned fields. */
116#define pg_edit_init(e,type,field) \
117   pg_edit_init_bitfield(e,type,field,0,STRUCT_BITS_OF(type,field))
118
119static inline uword
120pg_edit_n_alloc_bytes (pg_edit_t * e)
121{
122  int i0, i1, n_bytes, n_bits_left;
123
124  i0 = e->lsb_bit_offset;
125  i1 = i0 % BITS (u8);
126
127  n_bytes = 0;
128  n_bits_left = e->n_bits;
129
130  if (n_bits_left > 0 && i1 != 0)
131    {
132      n_bytes++;
133      n_bits_left -= i1;
134      if (n_bits_left < 0)
135	n_bits_left = 0;
136    }
137
138  n_bytes += (n_bits_left / BITS (u8));
139  n_bytes += (n_bits_left % BITS (u8)) != 0;
140
141  return n_bytes;
142}
143
144static inline void
145pg_edit_alloc_value (pg_edit_t * e, int i)
146{
147  vec_validate (e->values[i], e->lsb_bit_offset / BITS (u8));
148}
149
150extern void pg_edit_set_value (pg_edit_t * e, int hi_or_lo, u64 value);
151
152static inline void
153pg_edit_set_fixed (pg_edit_t * e, u64 value)
154{
155  e->type = PG_EDIT_FIXED;
156  pg_edit_set_value (e, PG_EDIT_LO, value);
157}
158
159static inline void
160pg_edit_copy_type_and_values (pg_edit_t * dst, pg_edit_t * src)
161{
162  int i;
163  dst->type = src->type;
164  src->type = PG_EDIT_INVALID_TYPE;
165  for (i = 0; i < ARRAY_LEN (dst->values); i++)
166    {
167      dst->values[i] = src->values[i];
168      src->values[i] = 0;
169    }
170}
171
172static inline u64
173pg_edit_get_value (pg_edit_t * e, int hi_or_lo)
174{
175  u64 r = 0;
176  int i, n;
177  u8 *v = e->values[hi_or_lo];
178
179  n = round_pow2 (e->n_bits, BITS (u8)) / BITS (u8);
180
181  ASSERT (n <= vec_len (v));
182  ASSERT (n <= sizeof (r));
183
184  for (i = 0; i < n; i++)
185    r = (r << BITS (v[i])) + v[i];
186
187  return r;
188}
189
190static inline uword
191pg_edit_is_fixed_with_value (pg_edit_t * e, u64 value)
192{
193  return (e->type == PG_EDIT_FIXED
194	  && value == pg_edit_get_value (e, PG_EDIT_LO));
195}
196
197uword unformat_pg_edit (unformat_input_t * input, va_list * args);
198uword unformat_pg_payload (unformat_input_t * input, va_list * args);
199uword unformat_pg_number (unformat_input_t * input, va_list * args);
200uword unformat_pg_interface (unformat_input_t * input, va_list * args);
201
202#endif /* included_packet_generator_pg_edit_h */
203
204/*
205 * fd.io coding-style-patch-verification: ON
206 *
207 * Local Variables:
208 * eval: (c-set-style "gnu")
209 * End:
210 */
211