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 = addattr_nest(n, 4096, TCA_OPTIONS);
 151
 152         while (argc > 0) {
 153                 if (matches(*argv, "map") == 0) {
 154                         mode = FLOW_MODE_MAP;
 155                 } else if (matches(*argv, "hash") == 0) {
 156                         mode = FLOW_MODE_HASH;
 157                 } else if (matches(*argv, "keys") == 0) {
 158                         NEXT_ARG();
 159                         if (flow_parse_keys(&keys, &nkeys, *argv))
 160                                 return -1;
 161                         addattr32(n, 4096, TCA_FLOW_KEYS, keys);
 162                 } else if (matches(*argv, "and") == 0) {
 163                         NEXT_ARG();
 164                         if (get_u32(&tmp, *argv, 0)) {
 165                                 fprintf(stderr, "Illegal \"mask\"\n");
 166                                 return -1;
 167                         }
 168                         transfer_bitop(&mask, &xor, tmp, 0);
 169                 } else if (matches(*argv, "or") == 0) {
 170                         NEXT_ARG();
 171                         if (get_u32(&tmp, *argv, 0)) {
 172                                 fprintf(stderr, "Illegal \"or\"\n");
 173                                 return -1;
 174                         }
 175                         transfer_bitop(&mask, &xor, ~tmp, tmp);
 176                 } else if (matches(*argv, "xor") == 0) {
 177                         NEXT_ARG();
 178                         if (get_u32(&tmp, *argv, 0)) {
 179                                 fprintf(stderr, "Illegal \"xor\"\n");
 180                                 return -1;
 181                         }
 182                         transfer_bitop(&mask, &xor, ~0, tmp);
 183                 } else if (matches(*argv, "rshift") == 0) {
 184                         NEXT_ARG();
 185                         if (get_u32(&tmp, *argv, 0)) {
 186                                 fprintf(stderr, "Illegal \"rshift\"\n");
 187                                 return -1;
 188                         }
 189                         addattr32(n, 4096, TCA_FLOW_RSHIFT, tmp);
 190                 } else if (matches(*argv, "addend") == 0) {
 191                         NEXT_ARG();
 192                         if (get_addend(&tmp, *argv, keys)) {
 193                                 fprintf(stderr, "Illegal \"addend\"\n");
 194                                 return -1;
 195                         }
 196                         addattr32(n, 4096, TCA_FLOW_ADDEND, tmp);
 197                 } else if (matches(*argv, "divisor") == 0) {
 198                         NEXT_ARG();
 199                         if (get_u32(&tmp, *argv, 0)) {
 200                                 fprintf(stderr, "Illegal \"divisor\"\n");
 201                                 return -1;
 202                         }
 203                         addattr32(n, 4096, TCA_FLOW_DIVISOR, tmp);
 204                 } else if (matches(*argv, "baseclass") == 0) {
 205                         NEXT_ARG();
 206                         if (get_tc_classid(&tmp, *argv) || TC_H_MIN(tmp) == 0) {
 207                                 fprintf(stderr, "Illegal \"baseclass\"\n");
 208                                 return -1;
 209                         }
 210                         addattr32(n, 4096, TCA_FLOW_BASECLASS, tmp);
 211                 } else if (matches(*argv, "perturb") == 0) {
 212                         NEXT_ARG();
 213                         if (get_u32(&tmp, *argv, 0)) {
 214                                 fprintf(stderr, "Illegal \"perturb\"\n");
 215                                 return -1;
 216                         }
 217                         addattr32(n, 4096, TCA_FLOW_PERTURB, tmp);
 218                 } else if (matches(*argv, "police") == 0) {
 219                         NEXT_ARG();
 220                         if (parse_police(&argc, &argv, TCA_FLOW_POLICE, n)) {
 221                                 fprintf(stderr, "Illegal \"police\"\n");
 222                                 return -1;
 223                         }
 224                         continue;
 225                 } else if (matches(*argv, "action") == 0) {
 226                         NEXT_ARG();
 227                         if (parse_action(&argc, &argv, TCA_FLOW_ACT, n)) {
 228                                 fprintf(stderr, "Illegal \"action\"\n");
 229                                 return -1;
 230                         }
 231                         continue;
 232                 } else if (matches(*argv, "match") == 0) {
 233                         NEXT_ARG();
 234                         if (parse_ematch(&argc, &argv, TCA_FLOW_EMATCHES, n)) {
 235                                 fprintf(stderr, "Illegal \"ematch\"\n");
 236                                 return -1;
 237                         }
 238                         continue;
 239                 } else if (matches(*argv, "help") == 0) {
 240                         explain();
 241                         return -1;
 242                 } else {
 243                         fprintf(stderr, "What is \"%s\"?\n", *argv);
 244                         explain();
 245                         return -1;
 246                 }
 247                 argv++, argc--;
 248         }
 249
 250         if (nkeys > 1 && mode != FLOW_MODE_HASH) {
 251                 fprintf(stderr, "Invalid mode \"map\" for multiple keys\n");
 252                 return -1;
 253         }
 254         addattr32(n, 4096, TCA_FLOW_MODE, mode);
 255
 256         if (mask != ~0 || xor != 0) {
 257                 addattr32(n, 4096, TCA_FLOW_MASK, mask);
 258                 addattr32(n, 4096, TCA_FLOW_XOR, xor);
 259         }
 260
 261         addattr_nest_end(n, tail);
 262         return 0;
 263 }
 264
 265 static int flow_print_opt(struct filter_util *fu, FILE *f, struct rtattr *opt,
 266                           __u32 handle)
 267 {
 268         struct rtattr *tb[TCA_FLOW_MAX+1];
 269
 270         SPRINT_BUF(b1);
 271         unsigned int i;
 272         __u32 mask = ~0, val = 0;
 273
 274         if (opt == NULL)
 275                 return -EINVAL;
 276
 277         parse_rtattr_nested(tb, TCA_FLOW_MAX, opt);
 278
 279         fprintf(f, "handle 0x%x ", handle);
 280
 281         if (tb[TCA_FLOW_MODE]) {
 282                 __u32 mode = rta_getattr_u32(tb[TCA_FLOW_MODE]);
 283
 284                 switch (mode) {
 285                 case FLOW_MODE_MAP:
 286                         fprintf(f, "map ");
 287                         break;
 288                 case FLOW_MODE_HASH:
 289                         fprintf(f, "hash ");
 290                         break;
 291                 }
 292         }
 293
 294         if (tb[TCA_FLOW_KEYS]) {
 295                 __u32 keymask = rta_getattr_u32(tb[TCA_FLOW_KEYS]);
 296                 char *sep = "";
 297
 298                 fprintf(f, "keys ");
 299                 for (i = 0; i <= FLOW_KEY_MAX; i++) {
 300                         if (keymask & (1 << i)) {
 301                                 fprintf(f, "%s%s", sep, flow_keys[i]);
 302                                 sep = ",";
 303                         }
 304                 }
 305                 fprintf(f, " ");
 306         }
 307
 308         if (tb[TCA_FLOW_MASK])
 309                 mask = rta_getattr_u32(tb[TCA_FLOW_MASK]);
 310         if (tb[TCA_FLOW_XOR])
 311                 val = rta_getattr_u32(tb[TCA_FLOW_XOR]);
 312
 313         if (mask != ~0 || val != 0) {
 314                 __u32 or = (mask & val) ^ val;
 315                 __u32 xor = mask & val;
 316
 317                 if (mask != ~0)
 318                         fprintf(f, "and 0x%.8x ", mask);
 319                 if (xor != 0)
 320                         fprintf(f, "xor 0x%.8x ", xor);
 321                 if (or != 0)
 322                         fprintf(f, "or 0x%.8x ", or);
 323         }
 324
 325         if (tb[TCA_FLOW_RSHIFT])
 326                 fprintf(f, "rshift %u ",
 327                         rta_getattr_u32(tb[TCA_FLOW_RSHIFT]));
 328         if (tb[TCA_FLOW_ADDEND])
 329                 fprintf(f, "addend 0x%x ",
 330                         rta_getattr_u32(tb[TCA_FLOW_ADDEND]));
 331
 332         if (tb[TCA_FLOW_DIVISOR])
 333                 fprintf(f, "divisor %u ",
 334                         rta_getattr_u32(tb[TCA_FLOW_DIVISOR]));
 335         if (tb[TCA_FLOW_BASECLASS])
 336                 fprintf(f, "baseclass %s ",
 337                         sprint_tc_classid(rta_getattr_u32(tb[TCA_FLOW_BASECLASS]), b1));
 338
 339         if (tb[TCA_FLOW_PERTURB])
 340                 fprintf(f, "perturb %usec ",
 341                         rta_getattr_u32(tb[TCA_FLOW_PERTURB]));
 342
 343         if (tb[TCA_FLOW_EMATCHES])
 344                 print_ematch(f, tb[TCA_FLOW_EMATCHES]);
 345         if (tb[TCA_FLOW_POLICE])
 346                 tc_print_police(f, tb[TCA_FLOW_POLICE]);
 347         if (tb[TCA_FLOW_ACT]) {
 348                 fprintf(f, "\n");
 349                 tc_print_action(f, tb[TCA_FLOW_ACT], 0);
 350         }
 351         return 0;
 352 }
 353
 354 struct filter_util flow_filter_util = {
 355         .id             = "flow",
 356         .parse_fopt     = flow_parse_opt,
 357         .print_fopt     = flow_print_opt,
 358 };