sync to iproute2-2.6.16-060323

[iproute2.git] / tc / em_nbyte.c

diff --git a/tc/em_nbyte.c b/tc/em_nbyte.c
new file mode 100644 (file)
index 0000000..e0ed5ba
--- /dev/null
+++ b/tc/em_nbyte.c
@@ -0,0 +1,144 @@
+/*
+ * em_nbyte.c          N-Byte 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_nbyte.h>
+
+extern struct ematch_util nbyte_ematch_util;
+
+static void nbyte_print_usage(FILE *fd)
+{
+       fprintf(fd,
+           "Usage: nbyte(NEEDLE at OFFSET [layer LAYER])\n" \
+           "where: NEEDLE := { string | \"c-escape-sequence\" }\n" \
+           "       OFFSET := int\n" \
+           "       LAYER  := { link | header | next-header | 0..%d }\n" \
+           "\n" \
+           "Example: nbyte(\"ababa\" at 12 layer 1)\n",
+           TCF_LAYER_MAX);
+}
+
+static int nbyte_parse_eopt(struct nlmsghdr *n, struct tcf_ematch_hdr *hdr,
+                           struct bstr *args)
+{
+       struct bstr *a;
+       struct bstr *needle = args;
+       unsigned long offset = 0, layer = TCF_LAYER_NETWORK;
+       int offset_present = 0;
+       struct tcf_em_nbyte nb;
+
+       memset(&nb, 0, sizeof(nb));
+
+#define PARSE_ERR(CARG, FMT, ARGS...) \
+       em_parse_error(EINVAL, args, CARG, &nbyte_ematch_util, FMT ,##ARGS)
+
+       if (args == NULL)
+               return PARSE_ERR(args, "nbyte: missing arguments");
+
+       if (needle->len <= 0)
+               return PARSE_ERR(args, "nbyte: needle length is 0");
+
+       for (a = bstr_next(args); a; a = bstr_next(a)) {
+               if (!bstrcmp(a, "at")) {
+                       if (a->next == NULL)
+                               return PARSE_ERR(a, "nbyte: missing argument");
+                       a = bstr_next(a);
+
+                       offset = bstrtoul(a);
+                       if (offset == ULONG_MAX)
+                               return PARSE_ERR(a, "nbyte: invalid offset, " \
+                                   "must be numeric");
+
+                       offset_present = 1;
+               } else if (!bstrcmp(a, "layer")) {
+                       if (a->next == NULL)
+                               return PARSE_ERR(a, "nbyte: 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, "nbyte: invalid " \
+                                           "layer");
+                       }
+
+                       if (layer > TCF_LAYER_MAX)
+                               return PARSE_ERR(a, "nbyte: illegal layer, " \
+                                   "must be in 0..%d", TCF_LAYER_MAX);
+               } else
+                       return PARSE_ERR(a, "nbyte: unknown parameter");
+       }
+
+       if (offset_present == 0)
+               return PARSE_ERR(a, "nbyte: offset required");
+       
+       nb.len = needle->len;
+       nb.layer = (__u8) layer;
+       nb.off = (__u16) offset;
+
+       addraw_l(n, MAX_MSG, hdr, sizeof(*hdr));
+       addraw_l(n, MAX_MSG, &nb, sizeof(nb));
+       addraw_l(n, MAX_MSG, needle->data, needle->len);
+
+#undef PARSE_ERR
+       return 0;
+}
+
+static int nbyte_print_eopt(FILE *fd, struct tcf_ematch_hdr *hdr, void *data,
+                           int data_len)
+{
+       int i;
+       struct tcf_em_nbyte *nb = data;
+       __u8 *needle;
+
+       if (data_len < sizeof(*nb)) {
+               fprintf(stderr, "NByte header size mismatch\n");
+               return -1;
+       }
+
+       if (data_len < sizeof(*nb) + nb->len) {
+               fprintf(stderr, "NByte payload size mismatch\n");
+               return -1;
+       }
+
+       needle = data + sizeof(*nb);
+
+       for (i = 0; i < nb->len; i++)
+               fprintf(fd, "%02x ", needle[i]);
+
+       fprintf(fd, "\"");
+       for (i = 0; i < nb->len; i++)
+               fprintf(fd, "%c", isprint(needle[i]) ? needle[i] : '.');
+       fprintf(fd, "\" at %d layer %d", nb->off, nb->layer);
+       
+       return 0;
+}
+
+struct ematch_util nbyte_ematch_util = {
+       .kind = "nbyte",
+       .kind_num = TCF_EM_NBYTE,
+       .parse_eopt = nbyte_parse_eopt,
+       .print_eopt = nbyte_print_eopt,
+       .print_usage = nbyte_print_usage
+};