ip/iplink_bareudp.c

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2
   3 #include <stdio.h>
   4 #include <linux/if_ether.h>
   5 #include <linux/if_link.h>
   6 #include <linux/netlink.h>
   7 #include <linux/rtnetlink.h>
   8
   9 #include "libnetlink.h"
  10 #include "rt_names.h"
  11 #include "utils.h"
  12 #include "ip_common.h"
  13 #include "json_print.h"
  14
  15 #define BAREUDP_ATTRSET(attrs, type) (((attrs) & (1L << (type))) != 0)
  16
  17 static void print_explain(FILE *f)
  18 {
  19         fprintf(f,
  20                 "Usage: ... bareudp dstport PORT\n"
  21                 "               ethertype PROTO\n"
  22                 "               [ srcportmin PORT ]\n"
  23                 "               [ [no]multiproto ]\n"
  24                 "\n"
  25                 "Where: PORT  := UDP_PORT\n"
  26                 "       PROTO := ETHERTYPE\n"
  27                 "\n"
  28                 "Note: ETHERTYPE can be given as number or as protocol name (\"ipv4\", \"ipv6\",\n"
  29                 "      \"mpls_uc\", etc.).\n"
  30         );
  31 }
  32
  33 static void explain(void)
  34 {
  35         print_explain(stderr);
  36 }
  37
  38 static void check_duparg(__u64 *attrs, int type, const char *key,
  39                          const char *argv)
  40 {
  41         if (!BAREUDP_ATTRSET(*attrs, type)) {
  42                 *attrs |= (1L << type);
  43                 return;
  44         }
  45         duparg2(key, argv);
  46 }
  47
  48 static int bareudp_parse_opt(struct link_util *lu, int argc, char **argv,
  49                              struct nlmsghdr *n)
  50 {
  51         bool multiproto = false;
  52         __u16 srcportmin = 0;
  53         __be16 ethertype = 0;
  54         __be16 dstport = 0;
  55         __u64 attrs = 0;
  56
  57         while (argc > 0) {
  58                 if (matches(*argv, "dstport") == 0) {
  59                         NEXT_ARG();
  60                         check_duparg(&attrs, IFLA_BAREUDP_PORT, "dstport",
  61                                      *argv);
  62                         if (get_be16(&dstport, *argv, 0))
  63                                 invarg("dstport", *argv);
  64                 } else if (matches(*argv, "ethertype") == 0)  {
  65                         NEXT_ARG();
  66                         check_duparg(&attrs, IFLA_BAREUDP_ETHERTYPE,
  67                                      "ethertype", *argv);
  68                         if (ll_proto_a2n(&ethertype, *argv))
  69                                 invarg("ethertype", *argv);
  70                 } else if (matches(*argv, "srcportmin") == 0) {
  71                         NEXT_ARG();
  72                         check_duparg(&attrs, IFLA_BAREUDP_SRCPORT_MIN,
  73                                      "srcportmin", *argv);
  74                         if (get_u16(&srcportmin, *argv, 0))
  75                                 invarg("srcportmin", *argv);
  76                 } else if (matches(*argv, "multiproto") == 0) {
  77                         check_duparg(&attrs, IFLA_BAREUDP_MULTIPROTO_MODE,
  78                                      *argv, *argv);
  79                         multiproto = true;
  80                 } else if (matches(*argv, "nomultiproto") == 0) {
  81                         check_duparg(&attrs, IFLA_BAREUDP_MULTIPROTO_MODE,
  82                                      *argv, *argv);
  83                         multiproto = false;
  84                 } else if (matches(*argv, "help") == 0) {
  85                         explain();
  86                         return -1;
  87                 } else {
  88                         fprintf(stderr, "bareudp: unknown command \"%s\"?\n",
  89                                 *argv);
  90                         explain();
  91                         return -1;
  92                 }
  93                 argc--, argv++;
  94         }
  95
  96         if (!BAREUDP_ATTRSET(attrs, IFLA_BAREUDP_PORT))
  97                 missarg("dstport");
  98         if (!BAREUDP_ATTRSET(attrs, IFLA_BAREUDP_ETHERTYPE))
  99                 missarg("ethertype");
 100
 101         addattr16(n, 1024, IFLA_BAREUDP_PORT, dstport);
 102         addattr16(n, 1024, IFLA_BAREUDP_ETHERTYPE, ethertype);
 103         if (BAREUDP_ATTRSET(attrs, IFLA_BAREUDP_SRCPORT_MIN))
 104                 addattr16(n, 1024, IFLA_BAREUDP_SRCPORT_MIN, srcportmin);
 105         if (multiproto)
 106                 addattr(n, 1024, IFLA_BAREUDP_MULTIPROTO_MODE);
 107
 108         return 0;
 109 }
 110
 111 static void bareudp_print_opt(struct link_util *lu, FILE *f,
 112                               struct rtattr *tb[])
 113 {
 114         if (!tb)
 115                 return;
 116
 117         if (tb[IFLA_BAREUDP_PORT])
 118                 print_uint(PRINT_ANY, "dstport", "dstport %u ",
 119                            rta_getattr_be16(tb[IFLA_BAREUDP_PORT]));
 120
 121         if (tb[IFLA_BAREUDP_ETHERTYPE]) {
 122                 struct rtattr *attr = tb[IFLA_BAREUDP_ETHERTYPE];
 123                 SPRINT_BUF(ethertype);
 124
 125                 print_string(PRINT_ANY, "ethertype", "ethertype %s ",
 126                              ll_proto_n2a(rta_getattr_u16(attr),
 127                                           ethertype, sizeof(ethertype)));
 128         }
 129
 130         if (tb[IFLA_BAREUDP_SRCPORT_MIN])
 131                 print_uint(PRINT_ANY, "srcportmin", "srcportmin %u ",
 132                            rta_getattr_u16(tb[IFLA_BAREUDP_SRCPORT_MIN]));
 133
 134         if (tb[IFLA_BAREUDP_MULTIPROTO_MODE])
 135                 print_bool(PRINT_ANY, "multiproto", "multiproto ", true);
 136         else
 137                 print_bool(PRINT_ANY, "multiproto", "nomultiproto ", false);
 138 }
 139
 140 static void bareudp_print_help(struct link_util *lu, int argc, char **argv,
 141                                FILE *f)
 142 {
 143         print_explain(f);
 144 }
 145
 146 struct link_util bareudp_link_util = {
 147         .id             = "bareudp",
 148         .maxattr        = IFLA_BAREUDP_MAX,
 149         .parse_opt      = bareudp_parse_opt,
 150         .print_opt      = bareudp_print_opt,
 151         .print_help     = bareudp_print_help,
 152 };