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