1 |
/* |
2 |
* Cisco 7200 (Predator) simulation platform. |
3 |
* Copyright (c) 2005,2006 Christophe Fillot (cf@utc.fr) |
4 |
* |
5 |
* NetIO Filtering. |
6 |
*/ |
7 |
|
8 |
#include <stdio.h> |
9 |
#include <stdlib.h> |
10 |
#include <string.h> |
11 |
#include <stdarg.h> |
12 |
#include <unistd.h> |
13 |
#include <errno.h> |
14 |
#include <signal.h> |
15 |
#include <fcntl.h> |
16 |
#include <ctype.h> |
17 |
#include <time.h> |
18 |
#include <sys/time.h> |
19 |
#include <sys/stat.h> |
20 |
#include <sys/types.h> |
21 |
#include <sys/ioctl.h> |
22 |
#include <sys/socket.h> |
23 |
#include <sys/un.h> |
24 |
#include <sys/wait.h> |
25 |
#include <netinet/in.h> |
26 |
#include <arpa/inet.h> |
27 |
#include <netdb.h> |
28 |
#include <pthread.h> |
29 |
|
30 |
#include "registry.h" |
31 |
#include "net.h" |
32 |
#include "net_io.h" |
33 |
#include "net_io_filter.h" |
34 |
|
35 |
/* Filter list */ |
36 |
static netio_pktfilter_t *pf_list = NULL; |
37 |
|
38 |
/* Find a filter */ |
39 |
netio_pktfilter_t *netio_filter_find(char *name) |
40 |
{ |
41 |
netio_pktfilter_t *pf; |
42 |
|
43 |
for(pf=pf_list;pf;pf=pf->next) |
44 |
if (!strcmp(pf->name,name)) |
45 |
return pf; |
46 |
|
47 |
return NULL; |
48 |
} |
49 |
|
50 |
/* Add a new filter */ |
51 |
int netio_filter_add(netio_pktfilter_t *pf) |
52 |
{ |
53 |
if (netio_filter_find(pf->name) != NULL) |
54 |
return(-1); |
55 |
|
56 |
pf->next = pf_list; |
57 |
pf_list = pf; |
58 |
return(0); |
59 |
} |
60 |
|
61 |
/* Bind a filter to a NIO */ |
62 |
int netio_filter_bind(netio_desc_t *nio,int direction,char *pf_name) |
63 |
{ |
64 |
netio_pktfilter_t *pf; |
65 |
|
66 |
if (!(pf = netio_filter_find(pf_name))) |
67 |
return(-1); |
68 |
|
69 |
if (direction == NETIO_FILTER_DIR_RX) { |
70 |
nio->rx_filter_data = NULL; |
71 |
nio->rx_filter = pf; |
72 |
} else { |
73 |
nio->tx_filter_data = NULL; |
74 |
nio->tx_filter = pf; |
75 |
} |
76 |
|
77 |
return(0); |
78 |
} |
79 |
|
80 |
/* Unbind a filter from a NIO */ |
81 |
int netio_filter_unbind(netio_desc_t *nio,int direction) |
82 |
{ |
83 |
netio_pktfilter_t *pf; |
84 |
void **opt; |
85 |
|
86 |
if (direction == NETIO_FILTER_DIR_RX) { |
87 |
opt = &nio->rx_filter_data; |
88 |
pf = nio->rx_filter; |
89 |
} else { |
90 |
opt = &nio->tx_filter_data; |
91 |
pf = nio->tx_filter; |
92 |
} |
93 |
|
94 |
if (!pf) |
95 |
return(-1); |
96 |
|
97 |
pf->free(nio,opt); |
98 |
return(0); |
99 |
} |
100 |
|
101 |
/* Setup a filter */ |
102 |
int netio_filter_setup(netio_desc_t *nio,int direction,int argc,char *argv[]) |
103 |
{ |
104 |
netio_pktfilter_t *pf; |
105 |
void **opt; |
106 |
|
107 |
if (direction == NETIO_FILTER_DIR_RX) { |
108 |
opt = &nio->rx_filter_data; |
109 |
pf = nio->rx_filter; |
110 |
} else { |
111 |
opt = &nio->tx_filter_data; |
112 |
pf = nio->tx_filter; |
113 |
} |
114 |
|
115 |
if (!pf) |
116 |
return(-1); |
117 |
|
118 |
return(pf->setup(nio,opt,argc,argv)); |
119 |
} |
120 |
|
121 |
/* ======================================================================== */ |
122 |
/* Frequency Dropping ("freq_drop"). */ |
123 |
/* ======================================================================== */ |
124 |
|
125 |
struct pf_freqdrop_data { |
126 |
int frequency; |
127 |
int current; |
128 |
}; |
129 |
|
130 |
/* Setup filter ressources */ |
131 |
static int pf_freqdrop_setup(netio_desc_t *nio,void **opt, |
132 |
int argc,char *argv[]) |
133 |
{ |
134 |
struct pf_freqdrop_data *data = *opt; |
135 |
|
136 |
if (argc != 1) |
137 |
return(-1); |
138 |
|
139 |
if (!data) { |
140 |
if (!(data = malloc(sizeof(*data)))) |
141 |
return(-1); |
142 |
|
143 |
*opt = data; |
144 |
} |
145 |
|
146 |
data->current = 0; |
147 |
data->frequency = atoi(argv[0]); |
148 |
return(0); |
149 |
} |
150 |
|
151 |
/* Free ressources used by filter */ |
152 |
static void pf_freqdrop_free(netio_desc_t *nio,void **opt) |
153 |
{ |
154 |
if (*opt) |
155 |
free(*opt); |
156 |
|
157 |
*opt = NULL; |
158 |
} |
159 |
|
160 |
/* Packet handler: drop 1 out of n packets */ |
161 |
static int pf_freqdrop_pkt_handler(netio_desc_t *nio,void *pkt,size_t len, |
162 |
void *opt) |
163 |
{ |
164 |
struct pf_freqdrop_data *data = opt; |
165 |
|
166 |
if (data != NULL) { |
167 |
switch(data->frequency) { |
168 |
case -1: |
169 |
return(NETIO_FILTER_ACTION_DROP); |
170 |
case 0: |
171 |
return(NETIO_FILTER_ACTION_PASS); |
172 |
default: |
173 |
data->current++; |
174 |
|
175 |
if (data->current == data->frequency) { |
176 |
data->current = 0; |
177 |
return(NETIO_FILTER_ACTION_DROP); |
178 |
} |
179 |
} |
180 |
} |
181 |
|
182 |
return(NETIO_FILTER_ACTION_PASS); |
183 |
} |
184 |
|
185 |
/* Packet dropping at 1/n frequency */ |
186 |
static netio_pktfilter_t pf_freqdrop_def = { |
187 |
"freq_drop", |
188 |
pf_freqdrop_setup, |
189 |
pf_freqdrop_free, |
190 |
pf_freqdrop_pkt_handler, |
191 |
NULL, |
192 |
}; |
193 |
|
194 |
/* ======================================================================== */ |
195 |
/* Initialization of packet filters. */ |
196 |
/* ======================================================================== */ |
197 |
|
198 |
void netio_filter_load_all(void) |
199 |
{ |
200 |
netio_filter_add(&pf_freqdrop_def); |
201 |
} |