libnl  3.2.27
cmp.c
1 /*
2  * lib/route/cls/ematch/cmp.c Simple packet data comparison ematch
3  *
4  * This library is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation version 2.1
7  * of the License.
8  *
9  * Copyright (c) 2008-2013 Thomas Graf <tgraf@suug.ch>
10  */
11 
12 /**
13  * @ingroup ematch
14  * @defgroup em_cmp Simple packet data comparison
15  *
16  * @{
17  */
18 
19 #include <netlink-private/netlink.h>
20 #include <netlink-private/tc.h>
21 #include <netlink/netlink.h>
22 #include <netlink/route/cls/ematch.h>
23 #include <netlink/route/cls/ematch/cmp.h>
24 #include <linux/tc_ematch/tc_em_cmp.h>
25 
26 void rtnl_ematch_cmp_set(struct rtnl_ematch *e, struct tcf_em_cmp *cfg)
27 {
28  memcpy(rtnl_ematch_data(e), cfg, sizeof(*cfg));
29 }
30 
31 struct tcf_em_cmp *rtnl_ematch_cmp_get(struct rtnl_ematch *e)
32 {
33  return rtnl_ematch_data(e);
34 }
35 
36 static int cmp_parse(struct rtnl_ematch *e, void *data, size_t len)
37 {
38  memcpy(rtnl_ematch_data(e), data, len);
39 
40  return 0;
41 }
42 
43 static const char *align_txt[] = {
44  [TCF_EM_ALIGN_U8] = "u8",
45  [TCF_EM_ALIGN_U16] = "u16",
46  [TCF_EM_ALIGN_U32] = "u32"
47 };
48 
49 static const char *layer_txt[] = {
50  [TCF_LAYER_LINK] = "eth",
51  [TCF_LAYER_NETWORK] = "ip",
52  [TCF_LAYER_TRANSPORT] = "tcp"
53 };
54 
55 static const char *operand_txt[] = {
56  [TCF_EM_OPND_EQ] = "=",
57  [TCF_EM_OPND_LT] = "<",
58  [TCF_EM_OPND_GT] = ">",
59 };
60 
61 static void cmp_dump(struct rtnl_ematch *e, struct nl_dump_params *p)
62 {
63  struct tcf_em_cmp *cmp = rtnl_ematch_data(e);
64 
65  if (cmp->flags & TCF_EM_CMP_TRANS)
66  nl_dump(p, "ntoh%c(", (cmp->align == TCF_EM_ALIGN_U32) ? 'l' : 's');
67 
68  nl_dump(p, "%s at %s+%u",
69  align_txt[cmp->align], layer_txt[cmp->layer], cmp->off);
70 
71  if (cmp->mask)
72  nl_dump(p, " & 0x%x", cmp->mask);
73 
74  if (cmp->flags & TCF_EM_CMP_TRANS)
75  nl_dump(p, ")");
76 
77  nl_dump(p, " %s %u", operand_txt[cmp->opnd], cmp->val);
78 }
79 
80 static struct rtnl_ematch_ops cmp_ops = {
81  .eo_kind = TCF_EM_CMP,
82  .eo_name = "cmp",
83  .eo_minlen = sizeof(struct tcf_em_cmp),
84  .eo_datalen = sizeof(struct tcf_em_cmp),
85  .eo_parse = cmp_parse,
86  .eo_dump = cmp_dump,
87 };
88 
89 static void __init cmp_init(void)
90 {
91  rtnl_ematch_register(&cmp_ops);
92 }
93 
94 /** @} */
int rtnl_ematch_register(struct rtnl_ematch_ops *ops)
Register ematch module.
Definition: ematch.c:45
Dumping parameters.
Definition: types.h:33
void nl_dump(struct nl_dump_params *params, const char *fmt,...)
Dump a formatted character string.
Definition: utils.c:914
Extended Match Operations.
Definition: ematch.h:33