-/*
- * em_cmp.c Simle coparison Ematch
- *
- * This program is free software; you can distribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- *
- * Authors: Thomas Graf <tgraf@suug.ch>
- */
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <syslog.h>
-#include <fcntl.h>
-#include <sys/socket.h>
-#include <netinet/in.h>
-#include <arpa/inet.h>
-#include <string.h>
-#include <dlfcn.h>
-#include <errno.h>
-
-#include "m_ematch.h"
-#include <linux/tc_ematch/tc_em_cmp.h>
-
-extern struct ematch_util cmp_ematch_util;
-
-static void cmp_print_usage(FILE *fd)
-{
- fprintf(fd,
- "Usage: cmp(ALIGN at OFFSET [ ATTRS ] { eq | lt | gt } VALUE)\n" \
- "where: ALIGN := { u8 | u16 | u32 }\n" \
- " ATTRS := [ layer LAYER ] [ mask MASK ] [ trans ]\n" \
- " LAYER := { link | header | next-header | 0..%d }\n" \
- "\n" \
- "Example: cmp(u16 at 3 layer 2 mask 0xff00 gt 20)\n",
- TCF_LAYER_MAX);
-}
-
-static int cmp_parse_eopt(struct nlmsghdr *n, struct tcf_ematch_hdr *hdr,
- struct bstr *args)
-{
- struct bstr *a;
- int align, opnd = 0;
- unsigned long offset = 0, layer = TCF_LAYER_NETWORK, mask = 0, value = 0;
- int offset_present = 0, value_present = 0;
- struct tcf_em_cmp cmp;
-
- memset(&cmp, 0, sizeof(cmp));
-
-#define PARSE_ERR(CARG, FMT, ARGS...) \
- em_parse_error(EINVAL, args, CARG, &cmp_ematch_util, FMT ,##ARGS)
-
- if (args == NULL)
- return PARSE_ERR(args, "cmp: missing arguments");
-
- if (!bstrcmp(args, "u8"))
- align = TCF_EM_ALIGN_U8;
- else if (!bstrcmp(args, "u16"))
- align = TCF_EM_ALIGN_U16;
- else if (!bstrcmp(args, "u32"))
- align = TCF_EM_ALIGN_U32;
- else
- return PARSE_ERR(args, "cmp: invalid alignment");
-
- for (a = bstr_next(args); a; a = bstr_next(a)) {
- if (!bstrcmp(a, "at")) {
- if (a->next == NULL)
- return PARSE_ERR(a, "cmp: missing argument");
- a = bstr_next(a);
-
- offset = bstrtoul(a);
- if (offset == ULONG_MAX)
- return PARSE_ERR(a, "cmp: invalid offset, " \
- "must be numeric");
-
- offset_present = 1;
- } else if (!bstrcmp(a, "layer")) {
- if (a->next == NULL)
- return PARSE_ERR(a, "cmp: missing argument");
- a = bstr_next(a);
-
- layer = parse_layer(a);
- if (layer == INT_MAX) {
- layer = bstrtoul(a);
- if (layer == ULONG_MAX)
- return PARSE_ERR(a, "cmp: invalid " \
- "layer");
- }
-
- if (layer > TCF_LAYER_MAX)
- return PARSE_ERR(a, "cmp: illegal layer, " \
- "must be in 0..%d", TCF_LAYER_MAX);
- } else if (!bstrcmp(a, "mask")) {
- if (a->next == NULL)
- return PARSE_ERR(a, "cmp: missing argument");
- a = bstr_next(a);
-
- mask = bstrtoul(a);
- if (mask == ULONG_MAX)
- return PARSE_ERR(a, "cmp: invalid mask");
- } else if (!bstrcmp(a, "trans")) {
- cmp.flags |= TCF_EM_CMP_TRANS;
- } else if (!bstrcmp(a, "eq") || !bstrcmp(a, "gt") ||
- !bstrcmp(a, "lt")) {
-
- if (!bstrcmp(a, "eq"))
- opnd = TCF_EM_OPND_EQ;
- else if (!bstrcmp(a, "gt"))
- opnd = TCF_EM_OPND_GT;
- else if (!bstrcmp(a, "lt"))
- opnd = TCF_EM_OPND_LT;
-
- if (a->next == NULL)
- return PARSE_ERR(a, "cmp: missing argument");
- a = bstr_next(a);
-
- value = bstrtoul(a);
- if (value == ULONG_MAX)
- return PARSE_ERR(a, "cmp: invalid value");
-
- value_present = 1;
- } else
- return PARSE_ERR(a, "nbyte: unknown parameter");
- }
-
- if (offset_present == 0 || value_present == 0)
- return PARSE_ERR(a, "cmp: offset and value required");
-
- cmp.val = (__u32) value;
- cmp.mask = (__u32) mask;
- cmp.off = (__u16) offset;
- cmp.align = (__u8) align;
- cmp.layer = (__u8) layer;
- cmp.opnd = (__u8) opnd;
-
- addraw_l(n, MAX_MSG, hdr, sizeof(*hdr));
- addraw_l(n, MAX_MSG, &cmp, sizeof(cmp));
-
-#undef PARSE_ERR
- return 0;
-}
-
-static int cmp_print_eopt(FILE *fd, struct tcf_ematch_hdr *hdr, void *data,
- int data_len)
-{
- struct tcf_em_cmp *cmp = data;
-
- if (data_len < sizeof(*cmp)) {
- fprintf(stderr, "CMP header size mismatch\n");
- return -1;
- }
-
- if (cmp->align == TCF_EM_ALIGN_U8)
- fprintf(fd, "u8 ");
- else if (cmp->align == TCF_EM_ALIGN_U16)
- fprintf(fd, "u16 ");
- else if (cmp->align == TCF_EM_ALIGN_U16)
- fprintf(fd, "u32 ");
-
- fprintf(fd, "at %d layer %d ", cmp->off, cmp->layer);
-
- if (cmp->mask)
- fprintf(fd, "mask 0x%x ", cmp->mask);
-
- if (cmp->flags & TCF_EM_CMP_TRANS)
- fprintf(fd, "trans ");
-
- if (cmp->opnd == TCF_EM_OPND_EQ)
- fprintf(fd, "eq ");
- else if (cmp->opnd == TCF_EM_OPND_LT)
- fprintf(fd, "lt ");
- else if (cmp->opnd == TCF_EM_OPND_GT)
- fprintf(fd, "gt ");
-
- fprintf(fd, "%d", cmp->val);
-
- return 0;
-}
-
-struct ematch_util cmp_ematch_util = {
- .kind = "cmp",
- .kind_num = TCF_EM_CMP,
- .parse_eopt = cmp_parse_eopt,
- .print_eopt = cmp_print_eopt,
- .print_usage = cmp_print_usage
-};