release/src/router/iptables/extensions/libipt_TOS.c

   1 /* Shared library add-on to iptables to add TOS target support. */
   2 #include <stdio.h>
   3 #include <string.h>
   4 #include <stdlib.h>
   5 #include <getopt.h>
   6
   7 #include <iptables.h>
   8 #include <linux/netfilter_ipv4/ip_tables.h>
   9 #include <linux/netfilter_ipv4/ipt_TOS.h>
  10
  11 struct tosinfo {
  12         struct ipt_entry_target t;
  13         struct ipt_tos_target_info tos;
  14 };
  15
  16 /* TOS names and values. */
  17 static
  18 struct TOS_value
  19 {
  20         unsigned char TOS;
  21         const char *name;
  22 } TOS_values[] = {
  23         { IPTOS_LOWDELAY,    "Minimize-Delay" },
  24         { IPTOS_THROUGHPUT,  "Maximize-Throughput" },
  25         { IPTOS_RELIABILITY, "Maximize-Reliability" },
  26         { IPTOS_MINCOST,     "Minimize-Cost" },
  27         { IPTOS_NORMALSVC,   "Normal-Service" },
  28 };
  29
  30 /* Function which prints out usage message. */
  31 static void
  32 help(void)
  33 {
  34         unsigned int i;
  35
  36         printf(
  37 "TOS target v%s options:\n"
  38 "  --set-tos value                   Set Type of Service field to one of the\n"
  39 "                                following numeric or descriptive values:\n",
  40 IPTABLES_VERSION);
  41
  42         for (i = 0; i < sizeof(TOS_values)/sizeof(struct TOS_value);i++)
  43                 printf("                                     %s %u (0x%02x)\n",
  44                        TOS_values[i].name,
  45                        TOS_values[i].TOS,
  46                        TOS_values[i].TOS);
  47         fputc('\n', stdout);
  48 }
  49
  50 static struct option opts[] = {
  51         { "set-tos", 1, 0, '1' },
  52         { 0 }
  53 };
  54
  55 /* Initialize the target. */
  56 static void
  57 init(struct ipt_entry_target *t, unsigned int *nfcache)
  58 {
  59 }
  60
  61 static void
  62 parse_tos(const char *s, struct ipt_tos_target_info *info)
  63 {
  64         unsigned int i, tos;
  65
  66         if (string_to_number(s, 0, 255, &tos) != -1) {
  67                 if (tos == IPTOS_LOWDELAY
  68                     || tos == IPTOS_THROUGHPUT
  69                     || tos == IPTOS_RELIABILITY
  70                     || tos == IPTOS_MINCOST
  71                     || tos == IPTOS_NORMALSVC) {
  72                         info->tos = (u_int8_t )tos;
  73                         return;
  74                 }
  75         } else {
  76                 for (i = 0; i<sizeof(TOS_values)/sizeof(struct TOS_value); i++)
  77                         if (strcasecmp(s,TOS_values[i].name) == 0) {
  78                                 info->tos = TOS_values[i].TOS;
  79                                 return;
  80                         }
  81         }
  82         exit_error(PARAMETER_PROBLEM, "Bad TOS value `%s'", s);
  83 }
  84
  85 /* Function which parses command options; returns true if it
  86    ate an option */
  87 static int
  88 parse(int c, char **argv, int invert, unsigned int *flags,
  89       const struct ipt_entry *entry,
  90       struct ipt_entry_target **target)
  91 {
  92         struct ipt_tos_target_info *tosinfo
  93                 = (struct ipt_tos_target_info *)(*target)->data;
  94
  95         switch (c) {
  96         case '1':
  97                 if (*flags)
  98                         exit_error(PARAMETER_PROBLEM,
  99                                    "TOS target: Cant specify --set-tos twice");
 100                 parse_tos(optarg, tosinfo);
 101                 *flags = 1;
 102                 break;
 103
 104         default:
 105                 return 0;
 106         }
 107
 108         return 1;
 109 }
 110
 111 static void
 112 final_check(unsigned int flags)
 113 {
 114         if (!flags)
 115                 exit_error(PARAMETER_PROBLEM,
 116                            "TOS target: Parameter --set-tos is required");
 117 }
 118
 119 static void
 120 print_tos(u_int8_t tos, int numeric)
 121 {
 122         unsigned int i;
 123
 124         if (!numeric) {
 125                 for (i = 0; i<sizeof(TOS_values)/sizeof(struct TOS_value); i++)
 126                         if (TOS_values[i].TOS == tos) {
 127                                 printf("%s ", TOS_values[i].name);
 128                                 return;
 129                         }
 130         }
 131         printf("0x%02x ", tos);
 132 }
 133
 134 /* Prints out the targinfo. */
 135 static void
 136 print(const struct ipt_ip *ip,
 137       const struct ipt_entry_target *target,
 138       int numeric)
 139 {
 140         const struct ipt_tos_target_info *tosinfo =
 141                 (const struct ipt_tos_target_info *)target->data;
 142         printf("TOS set ");
 143         print_tos(tosinfo->tos, numeric);
 144 }
 145
 146 /* Saves the union ipt_targinfo in parsable form to stdout. */
 147 static void
 148 save(const struct ipt_ip *ip, const struct ipt_entry_target *target)
 149 {
 150         const struct ipt_tos_target_info *tosinfo =
 151                 (const struct ipt_tos_target_info *)target->data;
 152
 153         printf("--set-tos 0x%02x ", tosinfo->tos);
 154 }
 155
 156 static struct iptables_target tos = {
 157         .next           = NULL,
 158         .name           = "TOS",
 159         .version        = IPTABLES_VERSION,
 160         .size           = IPT_ALIGN(sizeof(struct ipt_tos_target_info)),
 161         .userspacesize  = IPT_ALIGN(sizeof(struct ipt_tos_target_info)),
 162         .help           = &help,
 163         .init           = &init,
 164         .parse          = &parse,
 165         .final_check    = &final_check,
 166         .print          = &print,
 167         .save           = &save,
 168         .extra_opts     = opts
 169 };
 170
 171 void _init(void)
 172 {
 173         register_target(&tos);
 174 }