libnl: /data/src/libnl3/src/nl-pktloc-lookup.c Source File

libnl 3.10.0

nl-pktloc-lookup.c
1/* SPDX-License-Identifier: LGPL-2.1-only */
2/*
3 * Copyright (c) 2010 Thomas Graf <tgraf@suug.ch>
4 */
5
6#include "nl-default.h"
7
8#include <linux/tc_ematch/tc_em_cmp.h>
9
10#include <netlink/cli/utils.h>
11#include <netlink/route/pktloc.h>
12
13static void print_usage(void)
14{
15printf(
16"Usage: nl-pktloc-lookup [OPTIONS] <name>\n"
17"\n"
18"OPTIONS\n"
19" -h, --help Show this help text.\n"
20" -v, --version Show versioning information.\n"
21" -l, --list List all packet location definitions.\n"
22" --u32=VALUE Print in iproute2's u32 selector style\n"
23"\n"
24"\n"
25"EXAMPLE\n"
26" $ nl-pktloc-lookup ip.dst\n"
27" $ nl-pktloc-lookup --list\n"
28"\n"
29);
30 exit(0);
31}
32
33static const char *align_txt[] = {
34 [TCF_EM_ALIGN_U8] = "u8",
35 [TCF_EM_ALIGN_U16] = "u16",
36 [TCF_EM_ALIGN_U32] = "u32"
37};
38
39static uint32_t align_mask[] = {
40 [TCF_EM_ALIGN_U8] = 0xff,
41 [TCF_EM_ALIGN_U16] = 0xffff,
42 [TCF_EM_ALIGN_U32] = 0xffffffff,
43};
44
45static const char *layer_txt[] = {
46 [TCF_LAYER_LINK] = "eth",
47 [TCF_LAYER_NETWORK] = "ip",
48 [TCF_LAYER_TRANSPORT] = "tcp"
49};
50
51static const char *get_align_txt(struct rtnl_pktloc *loc, char buf[static 16])
52{
53 if (loc->align < _NL_N_ELEMENTS(align_txt))
54 return align_txt[loc->align];
55
56 snprintf(buf, 16, "%u", loc->align);
57 return buf;
58}
59
60static void dump_u32_style(struct rtnl_pktloc *loc, uint32_t value)
61{
62 char buf[16];
63
64 if (loc->align > 4)
65 nl_cli_fatal(EINVAL, "u32 only supports alignments u8|u16|u32.");
66
67 if (loc->layer == TCF_LAYER_LINK)
68 nl_cli_fatal(EINVAL, "u32 does not support link "
69 "layer locations.");
70
71 if (loc->shift > 0)
72 nl_cli_fatal(EINVAL, "u32 does not support shifting.");
73
74 printf("%s %x %x at %s%u\n", get_align_txt(loc, buf), value,
75 loc->mask ? loc->mask :
76 (loc->align < _NL_N_ELEMENTS(align_mask) ?
77 align_mask[loc->align] :
78 0),
79 loc->layer == TCF_LAYER_TRANSPORT ? "nexthdr+" : "",
80 loc->offset);
81}
82
83static void dump_loc(struct rtnl_pktloc *loc)
84{
85 char buf[16];
86
87 printf("%s = %s at %s+%u & %#x >> %u\n", loc->name,
88 get_align_txt(loc, buf),
89 loc->layer < _NL_N_ELEMENTS(layer_txt) ? layer_txt[loc->layer] :
90 "???",
91 loc->offset, loc->mask, loc->shift);
92}
93
94static void list_cb(struct rtnl_pktloc *loc, void *arg)
95{
96 char buf[16];
97
98 printf("%-26s %-5s %3s+%-4u %#-10x %-8u %u\n", loc->name,
99 get_align_txt(loc, buf),
100 loc->layer < _NL_N_ELEMENTS(layer_txt) ? layer_txt[loc->layer] :
101 "???",
102 loc->offset, loc->mask, loc->shift, loc->refcnt);
103}
104
105static void do_list(void)
106{
107 printf(
108"name align offset mask shift refcnt\n");
109 printf("---------------------------------------------------------\n");
110
111 rtnl_pktloc_foreach(&list_cb, NULL);
112}
113
114int main(int argc, char *argv[])
115{
116 struct rtnl_pktloc *loc;
117 int err, ustyle = 0;
118 uint32_t uvalue = 0;
119
120 for (;;) {
121 int c, optidx = 0;
122 enum {
123 ARG_U32 = 257,
124 };
125 static struct option long_opts[] = {
126 { "help", 0, 0, 'h' },
127 { "version", 0, 0, 'v' },
128 { "list", 0, 0, 'l' },
129 { "u32", 1, 0, ARG_U32 },
130 { 0, 0, 0, 0 }
131 };
132
133 c = getopt_long(argc, argv, "hvl", long_opts, &optidx);
134 if (c == -1)
135 break;
136
137 switch (c) {
138 case 'h': print_usage(); break;
139 case 'v': nl_cli_print_version(); break;
140 case 'l': do_list(); exit(0);
141 case ARG_U32:
142 ustyle = 1;
143 uvalue = nl_cli_parse_u32(optarg);
144 break;
145 }
146 }
147
148 if (optind >= argc)
149 print_usage();
150
151 if ((err = rtnl_pktloc_lookup(argv[optind++], &loc)) < 0)
152 nl_cli_fatal(err, "Unable to lookup packet location: %s",
153 nl_geterror(err));
154
155 if (ustyle)
156 dump_u32_style(loc, uvalue);
157 else
158 dump_loc(loc);
159
160 return 0;
161}
nl_cli_fatal
void nl_cli_fatal(int err, const char *fmt,...)
Print error message and quit application.
Definition utils.c:71
nl_cli_parse_u32
uint32_t nl_cli_parse_u32(const char *arg)
Parse a text based 32 bit unsigned integer argument.
Definition utils.c:36
rtnl_pktloc_lookup
int rtnl_pktloc_lookup(const char *name, struct rtnl_pktloc **result)
Lookup packet location alias.
Definition pktloc.c:171
rtnl_pktloc
Definition pktloc.h:20