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Vector Packet Processing
tcp_format.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  * tcp/tcp_format.c: tcp formatting
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/tcp/tcp.h>
42 
43 u8 *
44 format_tcp_flags (u8 * s, va_list * args)
45 {
46  int flags = va_arg (*args, int);
47 
48  s = format (s, "0x%02x", flags);
49 #define _(f) if (flags & TCP_FLAG_##f) s = format (s, " %s", #f);
51 #undef _
52  return s;
53 }
54 
55 /* Format TCP header. */
56 u8 *
57 format_tcp_header (u8 * s, va_list * args)
58 {
59  tcp_header_t *tcp = va_arg (*args, tcp_header_t *);
60  u32 max_header_bytes = va_arg (*args, u32);
61  u32 header_bytes;
62  uword indent;
63 
64  /* Nothing to do. */
65  if (max_header_bytes < sizeof (tcp[0]))
66  return format (s, "TCP header truncated");
67 
68  indent = format_get_indent (s);
69  indent += 2;
70  header_bytes = tcp_header_bytes (tcp);
71 
72  s = format (s, "TCP: %d -> %d", clib_net_to_host_u16 (tcp->src),
73  clib_net_to_host_u16 (tcp->dst));
74 
75  s = format (s, "\n%Useq. 0x%08x ack 0x%08x", format_white_space, indent,
76  clib_net_to_host_u32 (tcp->seq_number),
77  clib_net_to_host_u32 (tcp->ack_number));
78 
79  s = format (s, "\n%Uflags %U, tcp header: %d bytes", format_white_space,
80  indent, format_tcp_flags, tcp->flags, header_bytes);
81 
82  s = format (s, "\n%Uwindow %d, checksum 0x%04x", format_white_space, indent,
83  clib_net_to_host_u16 (tcp->window),
84  clib_net_to_host_u16 (tcp->checksum));
85 
86 
87 #if 0
88  /* Format TCP options. */
89  {
90  u8 *o;
91  u8 *option_start = (void *) (tcp + 1);
92  u8 *option_end = (void *) tcp + header_bytes;
93 
94  for (o = option_start; o < option_end;)
95  {
96  u32 length = o[1];
97  switch (o[0])
98  {
99  case TCP_OPTION_END:
100  length = 1;
101  o = option_end;
102  break;
103 
104  case TCP_OPTION_NOOP:
105  length = 1;
106  break;
107 
108  }
109  }
110  }
111 #endif
112 
113  /* Recurse into next protocol layer. */
114  if (max_header_bytes != 0 && header_bytes < max_header_bytes)
115  {
116  ip_main_t *im = &ip_main;
118 
119  pi = ip_get_tcp_udp_port_info (im, tcp->dst);
120 
121  if (pi && pi->format_header)
122  s = format (s, "\n%U%U", format_white_space, indent - 2,
123  pi->format_header,
124  /* next protocol header */ (void *) tcp + header_bytes,
125  max_header_bytes - header_bytes);
126  }
127 
128  return s;
129 }
130 
131 /*
132  * fd.io coding-style-patch-verification: ON
133  *
134  * Local Variables:
135  * eval: (c-set-style "gnu")
136  * End:
137  */
u8 * format(u8 *s, const char *fmt,...)
Definition: format.c:419
Definition: ip.h:106
No operation.
Definition: tcp_packet.h:105
struct _tcp_header tcp_header_t
u8 * format_tcp_header(u8 *s, va_list *args)
Definition: tcp_format.c:57
static uword format_get_indent(u8 *s)
Definition: format.h:72
u8 * format_white_space(u8 *s, va_list *va)
Definition: std-formats.c:113
ip_main_t ip_main
Definition: ip_init.c:42
u8 * format_tcp_flags(u8 *s, va_list *args)
Definition: tcp_format.c:44
static tcp_udp_port_info_t * ip_get_tcp_udp_port_info(ip_main_t *im, u32 port)
Definition: ip.h:142
unsigned int u32
Definition: types.h:88
format_function_t * format_header
Definition: ip.h:100
u64 uword
Definition: types.h:112
unsigned char u8
Definition: types.h:56
static int tcp_header_bytes(tcp_header_t *t)
Definition: tcp_packet.h:93
u32 flags
Definition: vhost-user.h:77