FD.io VPP  v19.08.1-401-g8e4ed521a
Vector Packet Processing
tcp_pg.c
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1 /*
2  * Copyright (c) 2016-2019 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/tcp_pg: TCP 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/ip/ip.h>
41 #include <vnet/pg/pg.h>
42 
43 /* TCP flags bit 0 first. */
44 #define foreach_tcp_flag \
45  _ (FIN) \
46  _ (SYN) \
47  _ (RST) \
48  _ (PSH) \
49  _ (ACK) \
50  _ (URG) \
51  _ (ECE) \
52  _ (CWR)
53 
54 static void
56  pg_stream_t * s,
57  pg_edit_group_t * g, u32 * packets, u32 n_packets)
58 {
60  u32 ip_offset, tcp_offset;
61 
62  tcp_offset = g->start_byte_offset;
63  ip_offset = (g - 1)->start_byte_offset;
64 
65  while (n_packets >= 1)
66  {
67  vlib_buffer_t *p0;
68  ip4_header_t *ip0;
69  tcp_header_t *tcp0;
70  ip_csum_t sum0;
71  u32 tcp_len0;
72 
73  p0 = vlib_get_buffer (vm, packets[0]);
74  n_packets -= 1;
75  packets += 1;
76 
77  ASSERT (p0->current_data == 0);
78  ip0 = (void *) (p0->data + ip_offset);
79  tcp0 = (void *) (p0->data + tcp_offset);
80  /* if IP length has been specified, then calculate the length based on buffer */
81  if (ip0->length == 0)
82  tcp_len0 = vlib_buffer_length_in_chain (vm, p0) - tcp_offset;
83  else
84  tcp_len0 = clib_net_to_host_u16 (ip0->length) - tcp_offset;
85 
86  /* Initialize checksum with header. */
87  if (BITS (sum0) == 32)
88  {
89  sum0 = clib_mem_unaligned (&ip0->src_address, u32);
90  sum0 =
91  ip_csum_with_carry (sum0,
93  }
94  else
95  sum0 = clib_mem_unaligned (&ip0->src_address, u64);
96 
97  sum0 = ip_csum_with_carry
98  (sum0, clib_host_to_net_u32 (tcp_len0 + (ip0->protocol << 16)));
99 
100  /* Invalidate possibly old checksum. */
101  tcp0->checksum = 0;
102 
103  sum0 =
104  ip_incremental_checksum_buffer (vm, p0, tcp_offset, tcp_len0, sum0);
105 
106  tcp0->checksum = ~ip_csum_fold (sum0);
107  }
108 }
109 
110 typedef struct
111 {
113  pg_edit_t seq_number, ack_number;
115 #define _(f) pg_edit_t f##_flag;
117 #undef _
122 
123 static inline void
125 {
126  /* Initialize fields that are not bit fields in the IP header. */
127 #define _(f) pg_edit_init (&p->f, tcp_header_t, f);
128  _(src);
129  _(dst);
130  _(seq_number);
131  _(ack_number);
132  _(window);
133  _(checksum);
134  _(urgent_pointer);
135 #undef _
136 
137  /* Initialize bit fields. */
138 #define _(f) \
139  pg_edit_init_bitfield (&p->f##_flag, tcp_header_t, \
140  flags, \
141  TCP_FLAG_BIT_##f, 1);
142 
144 #undef _
146  data_offset_and_reserved, 4, 4);
147 }
148 
149 uword
150 unformat_pg_tcp_header (unformat_input_t * input, va_list * args)
151 {
152  pg_stream_t *s = va_arg (*args, pg_stream_t *);
153  pg_tcp_header_t *p;
154  u32 group_index;
155 
156  p = pg_create_edit_group (s, sizeof (p[0]), sizeof (tcp_header_t),
157  &group_index);
158  pg_tcp_header_init (p);
159 
160  /* Defaults. */
161  pg_edit_set_fixed (&p->seq_number, 0);
162  pg_edit_set_fixed (&p->ack_number, 0);
163 
165  sizeof (tcp_header_t) / sizeof (u32));
166 
167  pg_edit_set_fixed (&p->window, 4096);
169 
170 #define _(f) pg_edit_set_fixed (&p->f##_flag, 0);
172 #undef _
174 
175  if (!unformat (input, "TCP: %U -> %U",
179  goto error;
180 
181  /* Parse options. */
182  while (1)
183  {
184  if (unformat (input, "window %U",
186  ;
187 
188  else if (unformat (input, "checksum %U",
190  ;
191 
192  else if (unformat (input, "seqnum %U", unformat_pg_edit,
194  ;
195  else if (unformat (input, "acknum %U", unformat_pg_edit,
197  ;
198  /* Flags. */
199 #define _(f) else if (unformat (input, #f)) pg_edit_set_fixed (&p->f##_flag, 1);
201 #undef _
202  /* Can't parse input: try next protocol level. */
203  else
204  break;
205  }
206 
207  {
208  ip_main_t *im = &ip_main;
209  u16 dst_port;
211 
212  pi = 0;
213  if (p->dst.type == PG_EDIT_FIXED)
214  {
215  dst_port = pg_edit_get_value (&p->dst, PG_EDIT_LO);
216  pi = ip_get_tcp_udp_port_info (im, dst_port);
217  }
218 
219  if (pi && pi->unformat_pg_edit
220  && unformat_user (input, pi->unformat_pg_edit, s))
221  ;
222 
223  else if (!unformat_user (input, unformat_pg_payload, s))
224  goto error;
225 
227  {
228  pg_edit_group_t *g = pg_stream_get_group (s, group_index);
230  g->edit_function_opaque = 0;
231  }
232 
233  return 1;
234  }
235 
236 error:
237  /* Free up any edits we may have added. */
238  pg_free_edit_group (s);
239  return 0;
240 }
241 
242 /*
243  * fd.io coding-style-patch-verification: ON
244  *
245  * Local Variables:
246  * eval: (c-set-style "gnu")
247  * End:
248  */
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:152
pg_edit_t data_offset_and_reserved
Definition: tcp_pg.c:114
#define PG_EDIT_LO
Definition: edit.h:83
ip4_address_t src_address
Definition: ip4_packet.h:170
Definition: pg.h:318
static void pg_edit_set_fixed(pg_edit_t *e, u64 value)
Definition: edit.h:153
i16 current_data
signed offset in data[], pre_data[] that we are currently processing.
Definition: buffer.h:110
unsigned long u64
Definition: types.h:89
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
#define foreach_tcp_flag
Definition: tcp_pg.c:44
u8 data[0]
Packet data.
Definition: buffer.h:181
pg_edit_t dst
Definition: tcp_pg.c:112
vl_api_address_t src
Definition: gre.api:51
uword unformat_user(unformat_input_t *input, unformat_function_t *func,...)
Definition: unformat.c:989
uword unformat_pg_edit(unformat_input_t *input, va_list *args)
Definition: edit.c:106
uword ip_csum_t
Definition: ip_packet.h:219
static ip_csum_t ip_csum_with_carry(ip_csum_t sum, ip_csum_t x)
Definition: ip_packet.h:222
Definition: ip.h:107
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:366
struct _tcp_header tcp_header_t
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:225
ip4_address_t dst_address
Definition: ip4_packet.h:170
uword unformat_pg_payload(unformat_input_t *input, va_list *args)
Definition: edit.c:127
pg_edit_type_t type
Definition: edit.h:66
foreach_tcp_flag pg_edit_t window
Definition: tcp_pg.c:118
pg_edit_t seq_number
Definition: tcp_pg.c:113
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:231
pg_edit_t urgent_pointer
Definition: tcp_pg.c:120
struct _unformat_input_t unformat_input_t
unsigned short u16
Definition: types.h:57
static u64 pg_edit_get_value(pg_edit_t *e, int hi_or_lo)
Definition: edit.h:173
pg_edit_t src
Definition: tcp_pg.c:112
#define pg_edit_init_bitfield(e, type, field, field_offset, field_n_bits)
Definition: edit.h:98
vl_api_address_t dst
Definition: gre.api:52
static void tcp_pg_edit_function(pg_main_t *pg, pg_stream_t *s, pg_edit_group_t *g, u32 *packets, u32 n_packets)
Definition: tcp_pg.c:55
vlib_main_t * vm
Definition: buffer.c:323
ip_main_t ip_main
Definition: ip_init.c:42
static tcp_udp_port_info_t * ip_get_tcp_udp_port_info(ip_main_t *im, u32 port)
Definition: ip.h:143
#define ASSERT(truth)
unformat_function_t * unformat_pg_edit
Definition: ip.h:104
static void pg_free_edit_group(pg_stream_t *s)
Definition: pg.h:284
#define clib_mem_unaligned(pointer, type)
Definition: types.h:155
uword edit_function_opaque
Definition: pg.h:79
Definition: pg.h:94
static vlib_main_t * vlib_get_main(void)
Definition: global_funcs.h:23
unformat_function_t unformat_tcp_udp_port
Definition: format.h:49
pg_edit_t checksum
Definition: tcp_pg.c:119
pg_edit_t ack_number
Definition: tcp_pg.c:113
VLIB buffer representation.
Definition: buffer.h:102
u64 uword
Definition: types.h:112
uword unformat_pg_tcp_header(unformat_input_t *input, va_list *args)
Definition: tcp_pg.c:150
uword unformat_pg_number(unformat_input_t *input, va_list *args)
Definition: edit.c:85
static void pg_tcp_header_init(pg_tcp_header_t *p)
Definition: tcp_pg.c:124
u16 dst_port
Definition: udp.api:42
#define BITS(x)
Definition: clib.h:61
static vlib_buffer_t * vlib_get_buffer(vlib_main_t *vm, u32 buffer_index)
Translate buffer index into buffer pointer.
Definition: buffer_funcs.h:85
static u16 ip_csum_fold(ip_csum_t c)
Definition: ip_packet.h:275
uword unformat(unformat_input_t *i, const char *fmt,...)
Definition: unformat.c:978