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 (at) suug.ch> 10 */ 11 12 #include <netlink/cli/utils.h> 13 #include <netlink/route/pktloc.h> 14 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 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 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 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 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 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 } 106 107 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
