tc/f_flow.c

   1 /*
   2  * f_flow.c             Flow filter
   3  *
   4  *              This program is free software; you can redistribute it and/or
   5  *              modify it under the terms of the GNU General Public License
   6  *              as published by the Free Software Foundation; either version
   7  *              2 of the License, or (at your option) any later version.
   8  *
   9  * Authors:     Patrick McHardy <kaber@trash.net>
  10  */
  11 #include <stdio.h>
  12 #include <stdlib.h>
  13 #include <unistd.h>
  14 #include <string.h>
  15 #include <errno.h>
  16
  17 #include "utils.h"
  18 #include "tc_util.h"
  19 #include "m_ematch.h"
  20
  21 static void explain(void)
  22 {
  23         fprintf(stderr,
  24 "Usage: ... flow ...\n"
  25 "\n"
  26 " [mapping mode]: map key KEY [ OPS ] ...\n"
  27 " [hashing mode]: hash keys KEY-LIST ... [ perturb SECS ]\n"
  28 "\n"
  29 "                 [ divisor NUM ] [ baseclass ID ] [ match EMATCH_TREE ]\n"
  30 "                 [ action ACTION_SPEC ]\n"
  31 "\n"
  32 "KEY-LIST := [ KEY-LIST , ] KEY\n"
  33 "KEY      := [ src | dst | proto | proto-src | proto-dst | iif | priority |\n"
  34 "              mark | nfct | nfct-src | nfct-dst | nfct-proto-src |\n"
  35 "              nfct-proto-dst | rt-classid | sk-uid | sk-gid |\n"
  36 "              vlan-tag | rxhash ]\n"
  37 "OPS      := [ or NUM | and NUM | xor NUM | rshift NUM | addend NUM ]\n"
  38 "ID       := X:Y\n"
  39         );
  40 }
  41
  42 static const char *flow_keys[FLOW_KEY_MAX+1] = {
  43         [FLOW_KEY_SRC]                  = "src",
  44         [FLOW_KEY_DST]                  = "dst",
  45         [FLOW_KEY_PROTO]                = "proto",
  46         [FLOW_KEY_PROTO_SRC]            = "proto-src",
  47         [FLOW_KEY_PROTO_DST]            = "proto-dst",
  48         [FLOW_KEY_IIF]                  = "iif",
  49         [FLOW_KEY_PRIORITY]             = "priority",
  50         [FLOW_KEY_MARK]                 = "mark",
  51         [FLOW_KEY_NFCT]                 = "nfct",
  52         [FLOW_KEY_NFCT_SRC]             = "nfct-src",
  53         [FLOW_KEY_NFCT_DST]             = "nfct-dst",
  54         [FLOW_KEY_NFCT_PROTO_SRC]       = "nfct-proto-src",
  55         [FLOW_KEY_NFCT_PROTO_DST]       = "nfct-proto-dst",
  56         [FLOW_KEY_RTCLASSID]            = "rt-classid",
  57         [FLOW_KEY_SKUID]                = "sk-uid",
  58         [FLOW_KEY_SKGID]                = "sk-gid",
  59         [FLOW_KEY_VLAN_TAG]             = "vlan-tag",
  60         [FLOW_KEY_RXHASH]               = "rxhash",
  61 };
  62
  63 static int flow_parse_keys(__u32 *keys, __u32 *nkeys, char *argv)
  64 {
  65         char *s, *sep;
  66         unsigned int i;
  67
  68         *keys = 0;
  69         *nkeys = 0;
  70         s = argv;
  71         while (s != NULL) {
  72                 sep = strchr(s, ',');
  73                 if (sep)
  74                         *sep = '\0';
  75
  76                 for (i = 0; i <= FLOW_KEY_MAX; i++) {
  77                         if (matches(s, flow_keys[i]) == 0) {
  78                                 *keys |= 1 << i;
  79                                 (*nkeys)++;
  80                                 break;
  81                         }
  82                 }
  83                 if (i > FLOW_KEY_MAX) {
  84                         fprintf(stderr, "Unknown flow key \"%s\"\n", s);
  85                         return -1;
  86                 }
  87                 s = sep ? sep + 1 : NULL;
  88         }
  89         return 0;
  90 }
  91
  92 static void transfer_bitop(__u32 *mask, __u32 *xor, __u32 m, __u32 x)
  93 {
  94         *xor = x ^ (*xor & m);
  95         *mask &= m;
  96 }
  97
  98 static int get_addend(__u32 *addend, char *argv, __u32 keys)
  99 {
 100         inet_prefix addr;
 101         int sign = 0;
 102         __u32 tmp;
 103
 104         if (*argv == '-') {
 105                 sign = 1;
 106                 argv++;
 107         }
 108
 109         if (get_u32(&tmp, argv, 0) == 0)
 110                 goto out;
 111
 112         if (keys & (FLOW_KEY_SRC | FLOW_KEY_DST |
 113                     FLOW_KEY_NFCT_SRC | FLOW_KEY_NFCT_DST) &&
 114             get_addr(&addr, argv, AF_UNSPEC) == 0) {
 115                 switch (addr.family) {
 116                 case AF_INET:
 117                         tmp = ntohl(addr.data[0]);
 118                         goto out;
 119                 case AF_INET6:
 120                         tmp = ntohl(addr.data[3]);
 121                         goto out;
 122                 }
 123         }
 124
 125         return -1;
 126 out:
 127         if (sign)
 128                 tmp = -tmp;
 129         *addend = tmp;
 130         return 0;
 131 }
 132
 133 static int flow_parse_opt(struct filter_util *fu, char *handle,
 134                           int argc, char **argv, struct nlmsghdr *n)
 135 {
 136         struct tcmsg *t = NLMSG_DATA(n);
 137         struct rtattr *tail;
 138         __u32 mask = ~0U, xor = 0;
 139         __u32 keys = 0, nkeys = 0;
 140         __u32 mode = FLOW_MODE_MAP;
 141         __u32 tmp;
 142
 143         if (handle) {
 144                 if (get_u32(&t->tcm_handle, handle, 0)) {
 145                         fprintf(stderr, "Illegal \"handle\"\n");
 146                         return -1;
 147                 }
 148         }
 149
 150         tail = NLMSG_TAIL(n);
 151         addattr_l(n, 4096, TCA_OPTIONS, NULL, 0);
 152
 153         while (argc > 0) {
 154                 if (matches(*argv, "map") == 0) {
 155                         mode = FLOW_MODE_MAP;
 156                 } else if (matches(*argv, "hash") == 0) {
 157                         mode = FLOW_MODE_HASH;
 158                 } else if (matches(*argv, "keys") == 0) {
 159                         NEXT_ARG();
 160                         if (flow_parse_keys(&keys, &nkeys, *argv))
 161                                 return -1;
 162                         addattr32(n, 4096, TCA_FLOW_KEYS, keys);
 163                 } else if (matches(*argv, "and") == 0) {
 164                         NEXT_ARG();
 165                         if (get_u32(&tmp, *argv, 0)) {
 166                                 fprintf(stderr, "Illegal \"mask\"\n");
 167                                 return -1;
 168                         }
 169                         transfer_bitop(&mask, &xor, tmp, 0);
 170                 } else if (matches(*argv, "or") == 0) {
 171                         NEXT_ARG();
 172                         if (get_u32(&tmp, *argv, 0)) {
 173                                 fprintf(stderr, "Illegal \"or\"\n");
 174                                 return -1;
 175                         }
 176                         transfer_bitop(&mask, &xor, ~tmp, tmp);
 177                 } else if (matches(*argv, "xor") == 0) {
 178                         NEXT_ARG();
 179                         if (get_u32(&tmp, *argv, 0)) {
 180                                 fprintf(stderr, "Illegal \"xor\"\n");
 181                                 return -1;
 182                         }
 183                         transfer_bitop(&mask, &xor, ~0, tmp);
 184                 } else if (matches(*argv, "rshift") == 0) {
 185                         NEXT_ARG();
 186                         if (get_u32(&tmp, *argv, 0)) {
 187                                 fprintf(stderr, "Illegal \"rshift\"\n");
 188                                 return -1;
 189                         }
 190                         addattr32(n, 4096, TCA_FLOW_RSHIFT, tmp);
 191                 } else if (matches(*argv, "addend") == 0) {
 192                         NEXT_ARG();
 193                         if (get_addend(&tmp, *argv, keys)) {
 194                                 fprintf(stderr, "Illegal \"addend\"\n");
 195                                 return -1;
 196                         }
 197                         addattr32(n, 4096, TCA_FLOW_ADDEND, tmp);
 198                 } else if (matches(*argv, "divisor") == 0) {
 199                         NEXT_ARG();
 200                         if (get_u32(&tmp, *argv, 0)) {
 201                                 fprintf(stderr, "Illegal \"divisor\"\n");
 202                                 return -1;
 203                         }
 204                         addattr32(n, 4096, TCA_FLOW_DIVISOR, tmp);
 205                 } else if (matches(*argv, "baseclass") == 0) {
 206                         NEXT_ARG();
 207                         if (get_tc_classid(&tmp, *argv) || TC_H_MIN(tmp) == 0) {
 208                                 fprintf(stderr, "Illegal \"baseclass\"\n");
 209                                 return -1;
 210                         }
 211                         addattr32(n, 4096, TCA_FLOW_BASECLASS, tmp);
 212                 } else if (matches(*argv, "perturb") == 0) {
 213                         NEXT_ARG();
 214                         if (get_u32(&tmp, *argv, 0)) {
 215                                 fprintf(stderr, "Illegal \"perturb\"\n");
 216                                 return -1;
 217                         }
 218                         addattr32(n, 4096, TCA_FLOW_PERTURB, tmp);
 219                 } else if (matches(*argv, "police") == 0) {
 220                         NEXT_ARG();
 221                         if (parse_police(&argc, &argv, TCA_FLOW_POLICE, n)) {
 222                                 fprintf(stderr, "Illegal \"police\"\n");
 223                                 return -1;
 224                         }
 225                         continue;
 226                 } else if (matches(*argv, "action") == 0) {
 227                         NEXT_ARG();
 228                         if (parse_action(&argc, &argv, TCA_FLOW_ACT, n)) {
 229                                 fprintf(stderr, "Illegal \"action\"\n");
 230                                 return -1;
 231                         }
 232                         continue;
 233                 } else if (matches(*argv, "match") == 0) {
 234                         NEXT_ARG();
 235                         if (parse_ematch(&argc, &argv, TCA_FLOW_EMATCHES, n)) {
 236                                 fprintf(stderr, "Illegal \"ematch\"\n");
 237                                 return -1;
 238                         }
 239                         continue;
 240                 } else if (matches(*argv, "help") == 0) {
 241                         explain();
 242                         return -1;
 243                 } else {
 244                         fprintf(stderr, "What is \"%s\"?\n", *argv);
 245                         explain();
 246                         return -1;
 247                 }
 248                 argv++, argc--;
 249         }
 250
 251         if (nkeys > 1 && mode != FLOW_MODE_HASH) {
 252                 fprintf(stderr, "Invalid mode \"map\" for multiple keys\n");
 253                 return -1;
 254         }
 255         addattr32(n, 4096, TCA_FLOW_MODE, mode);
 256
 257         if (mask != ~0 || xor != 0) {
 258                 addattr32(n, 4096, TCA_FLOW_MASK, mask);
 259                 addattr32(n, 4096, TCA_FLOW_XOR, xor);
 260         }
 261
 262         tail->rta_len = (void *)NLMSG_TAIL(n) - (void *)tail;
 263         return 0;
 264 }
 265
 266 static int flow_print_opt(struct filter_util *fu, FILE *f, struct rtattr *opt,
 267                           __u32 handle)
 268 {
 269         struct rtattr *tb[TCA_FLOW_MAX+1];
 270
 271         SPRINT_BUF(b1);
 272         unsigned int i;
 273         __u32 mask = ~0, val = 0;
 274
 275         if (opt == NULL)
 276                 return -EINVAL;
 277
 278         parse_rtattr_nested(tb, TCA_FLOW_MAX, opt);
 279
 280         fprintf(f, "handle 0x%x ", handle);
 281
 282         if (tb[TCA_FLOW_MODE]) {
 283                 __u32 mode = rta_getattr_u32(tb[TCA_FLOW_MODE]);
 284
 285                 switch (mode) {
 286                 case FLOW_MODE_MAP:
 287                         fprintf(f, "map ");
 288                         break;
 289                 case FLOW_MODE_HASH:
 290                         fprintf(f, "hash ");
 291                         break;
 292                 }
 293         }
 294
 295         if (tb[TCA_FLOW_KEYS]) {
 296                 __u32 keymask = rta_getattr_u32(tb[TCA_FLOW_KEYS]);
 297                 char *sep = "";
 298
 299                 fprintf(f, "keys ");
 300                 for (i = 0; i <= FLOW_KEY_MAX; i++) {
 301                         if (keymask & (1 << i)) {
 302                                 fprintf(f, "%s%s", sep, flow_keys[i]);
 303                                 sep = ",";
 304                         }
 305                 }
 306                 fprintf(f, " ");
 307         }
 308
 309         if (tb[TCA_FLOW_MASK])
 310                 mask = rta_getattr_u32(tb[TCA_FLOW_MASK]);
 311         if (tb[TCA_FLOW_XOR])
 312                 val = rta_getattr_u32(tb[TCA_FLOW_XOR]);
 313
 314         if (mask != ~0 || val != 0) {
 315                 __u32 or = (mask & val) ^ val;
 316                 __u32 xor = mask & val;
 317
 318                 if (mask != ~0)
 319                         fprintf(f, "and 0x%.8x ", mask);
 320                 if (xor != 0)
 321                         fprintf(f, "xor 0x%.8x ", xor);
 322                 if (or != 0)
 323                         fprintf(f, "or 0x%.8x ", or);
 324         }
 325
 326         if (tb[TCA_FLOW_RSHIFT])
 327                 fprintf(f, "rshift %u ",
 328                         rta_getattr_u32(tb[TCA_FLOW_RSHIFT]));
 329         if (tb[TCA_FLOW_ADDEND])
 330                 fprintf(f, "addend 0x%x ",
 331                         rta_getattr_u32(tb[TCA_FLOW_ADDEND]));
 332
 333         if (tb[TCA_FLOW_DIVISOR])
 334                 fprintf(f, "divisor %u ",
 335                         rta_getattr_u32(tb[TCA_FLOW_DIVISOR]));
 336         if (tb[TCA_FLOW_BASECLASS])
 337                 fprintf(f, "baseclass %s ",
 338                         sprint_tc_classid(rta_getattr_u32(tb[TCA_FLOW_BASECLASS]), b1));
 339
 340         if (tb[TCA_FLOW_PERTURB])
 341                 fprintf(f, "perturb %usec ",
 342                         rta_getattr_u32(tb[TCA_FLOW_PERTURB]));
 343
 344         if (tb[TCA_FLOW_EMATCHES])
 345                 print_ematch(f, tb[TCA_FLOW_EMATCHES]);
 346         if (tb[TCA_FLOW_POLICE])
 347                 tc_print_police(f, tb[TCA_FLOW_POLICE]);
 348         if (tb[TCA_FLOW_ACT]) {
 349                 fprintf(f, "\n");
 350                 tc_print_action(f, tb[TCA_FLOW_ACT], 0);
 351         }
 352         return 0;
 353 }
 354
 355 struct filter_util flow_filter_util = {
 356         .id             = "flow",
 357         .parse_fopt     = flow_parse_opt,
 358         .print_fopt     = flow_print_opt,
 359 };