libnl  3.7.0
text.c
1 /* SPDX-License-Identifier: LGPL-2.1-only */
2 /*
3  * Copyright (c) 2010-2013 Thomas Graf <tgraf@suug.ch>
4  */
5 
6 /**
7  * @ingroup ematch
8  * @defgroup em_text Text Search
9  *
10  * @{
11  */
12 
13 #include <netlink-private/netlink.h>
14 #include <netlink-private/utils.h>
15 #include <netlink-private/tc.h>
16 #include <netlink/netlink.h>
17 #include <netlink/route/cls/ematch.h>
18 #include <netlink/route/cls/ematch/text.h>
19 #include <linux/tc_ematch/tc_em_text.h>
20 
21 struct text_data
22 {
23  struct tcf_em_text cfg;
24  char * pattern;
25 };
26 
27 void rtnl_ematch_text_set_from(struct rtnl_ematch *e, uint8_t layer,
28  uint16_t offset)
29 {
30  struct text_data *t = rtnl_ematch_data(e);
31  t->cfg.from_offset = offset;
32  t->cfg.from_layer = layer;
33 }
34 
35 uint16_t rtnl_ematch_text_get_from_offset(struct rtnl_ematch *e)
36 {
37  return ((struct text_data *) rtnl_ematch_data(e))->cfg.from_offset;
38 }
39 
40 uint8_t rtnl_ematch_text_get_from_layer(struct rtnl_ematch *e)
41 {
42  return ((struct text_data *) rtnl_ematch_data(e))->cfg.from_layer;
43 }
44 
45 void rtnl_ematch_text_set_to(struct rtnl_ematch *e, uint8_t layer,
46  uint16_t offset)
47 {
48  struct text_data *t = rtnl_ematch_data(e);
49  t->cfg.to_offset = offset;
50  t->cfg.to_layer = layer;
51 }
52 
53 uint16_t rtnl_ematch_text_get_to_offset(struct rtnl_ematch *e)
54 {
55  return ((struct text_data *) rtnl_ematch_data(e))->cfg.to_offset;
56 }
57 
58 uint8_t rtnl_ematch_text_get_to_layer(struct rtnl_ematch *e)
59 {
60  return ((struct text_data *) rtnl_ematch_data(e))->cfg.to_layer;
61 }
62 
63 void rtnl_ematch_text_set_pattern(struct rtnl_ematch *e,
64  char *pattern, size_t len)
65 {
66  struct text_data *t = rtnl_ematch_data(e);
67 
68  if (t->pattern)
69  free(t->pattern);
70 
71  t->pattern = pattern;
72  t->cfg.pattern_len = len;
73 }
74 
75 char *rtnl_ematch_text_get_pattern(struct rtnl_ematch *e)
76 {
77  return ((struct text_data *) rtnl_ematch_data(e))->pattern;
78 }
79 
80 size_t rtnl_ematch_text_get_len(struct rtnl_ematch *e)
81 {
82  return ((struct text_data *) rtnl_ematch_data(e))->cfg.pattern_len;
83 }
84 
85 void rtnl_ematch_text_set_algo(struct rtnl_ematch *e, const char *algo)
86 {
87  struct text_data *t = rtnl_ematch_data(e);
88 
89  _nl_strncpy_trunc(t->cfg.algo, algo, sizeof(t->cfg.algo));
90 }
91 
92 char *rtnl_ematch_text_get_algo(struct rtnl_ematch *e)
93 {
94  struct text_data *t = rtnl_ematch_data(e);
95 
96  return t->cfg.algo[0] ? t->cfg.algo : NULL;
97 }
98 
99 static int text_parse(struct rtnl_ematch *e, void *data, size_t len)
100 {
101  struct text_data *t = rtnl_ematch_data(e);
102  size_t hdrlen = sizeof(struct tcf_em_text);
103  size_t plen = len - hdrlen;
104 
105  memcpy(&t->cfg, data, hdrlen);
106 
107  if (t->cfg.pattern_len > plen)
108  return -NLE_INVAL;
109 
110  if (t->cfg.pattern_len > 0) {
111  if (!(t->pattern = calloc(1, t->cfg.pattern_len)))
112  return -NLE_NOMEM;
113 
114  memcpy(t->pattern, (char *) data + hdrlen, t->cfg.pattern_len);
115  }
116 
117  return 0;
118 }
119 
120 static void text_dump(struct rtnl_ematch *e, struct nl_dump_params *p)
121 {
122  struct text_data *t = rtnl_ematch_data(e);
123  char buf[64];
124 
125  nl_dump(p, "text(%s \"%s\"",
126  t->cfg.algo[0] ? t->cfg.algo : "no-algo",
127  t->pattern ? t->pattern : "no-pattern");
128 
129  if (t->cfg.from_layer || t->cfg.from_offset) {
130  nl_dump(p, " from %s",
131  rtnl_ematch_offset2txt(t->cfg.from_layer,
132  t->cfg.from_offset,
133  buf, sizeof(buf)));
134  }
135 
136  if (t->cfg.to_layer || t->cfg.to_offset) {
137  nl_dump(p, " to %s",
138  rtnl_ematch_offset2txt(t->cfg.to_layer,
139  t->cfg.to_offset,
140  buf, sizeof(buf)));
141  }
142 
143  nl_dump(p, ")");
144 }
145 
146 static int text_fill(struct rtnl_ematch *e, struct nl_msg *msg)
147 {
148  struct text_data *t = rtnl_ematch_data(e);
149  int err;
150 
151  if ((err = nlmsg_append(msg, &t->cfg, sizeof(t->cfg), 0)) < 0)
152  return err;
153 
154  return nlmsg_append(msg, t->pattern, t->cfg.pattern_len, 0);
155 }
156 
157 static void text_free(struct rtnl_ematch *e)
158 {
159  struct text_data *t = rtnl_ematch_data(e);
160  free(t->pattern);
161 }
162 
163 static struct rtnl_ematch_ops text_ops = {
164  .eo_kind = TCF_EM_TEXT,
165  .eo_name = "text",
166  .eo_minlen = sizeof(struct tcf_em_text),
167  .eo_datalen = sizeof(struct text_data),
168  .eo_parse = text_parse,
169  .eo_dump = text_dump,
170  .eo_fill = text_fill,
171  .eo_free = text_free,
172 };
173 
174 static void __init text_init(void)
175 {
176  rtnl_ematch_register(&text_ops);
177 }
178 
179 /** @} */
int rtnl_ematch_register(struct rtnl_ematch_ops *ops)
Register ematch module.
Definition: ematch.c:40
int nlmsg_append(struct nl_msg *n, void *data, size_t len, int pad)
Append data to tail of a netlink message.
Definition: msg.c:442
void nl_dump(struct nl_dump_params *params, const char *fmt,...)
Dump a formatted character string.
Definition: utils.c:955
Dumping parameters.
Definition: types.h:28
Extended Match Operations.
Definition: ematch.h:28
Definition: text.c:22