[PKT_SCHED]: Packet classification based on textsearch (ematch)
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/em_text.c b/net/sched/em_text.c
new file mode 100644
index 0000000..873840d
--- /dev/null
+++ b/net/sched/em_text.c
@@ -0,0 +1,157 @@
+/*
+ * net/sched/em_text.c Textsearch ematch
+ *
+ * This program is free software; you can redistribute 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 <linux/config.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/string.h>
+#include <linux/skbuff.h>
+#include <linux/textsearch.h>
+#include <linux/tc_ematch/tc_em_text.h>
+#include <net/pkt_cls.h>
+
+struct text_match
+{
+ u16 from_offset;
+ u16 to_offset;
+ u8 from_layer;
+ u8 to_layer;
+ struct ts_config *config;
+};
+
+#define EM_TEXT_PRIV(m) ((struct text_match *) (m)->data)
+
+static int em_text_match(struct sk_buff *skb, struct tcf_ematch *m,
+ struct tcf_pkt_info *info)
+{
+ struct text_match *tm = EM_TEXT_PRIV(m);
+ int from, to;
+ struct ts_state state;
+
+ from = tcf_get_base_ptr(skb, tm->from_layer) - skb->data;
+ from += tm->from_offset;
+
+ to = tcf_get_base_ptr(skb, tm->to_layer) - skb->data;
+ to += tm->to_offset;
+
+ return skb_find_text(skb, from, to, tm->config, &state) != UINT_MAX;
+}
+
+static int em_text_change(struct tcf_proto *tp, void *data, int len,
+ struct tcf_ematch *m)
+{
+ struct text_match *tm;
+ struct tcf_em_text *conf = data;
+ struct ts_config *ts_conf;
+ int flags = 0;
+
+ printk("Configuring text: %s from %d:%d to %d:%d len %d\n", conf->algo, conf->from_offset,
+ conf->from_layer, conf->to_offset, conf->to_layer, conf->pattern_len);
+
+ if (len < sizeof(*conf) || len < (sizeof(*conf) + conf->pattern_len))
+ return -EINVAL;
+
+ if (conf->from_layer > conf->to_layer)
+ return -EINVAL;
+
+ if (conf->from_layer == conf->to_layer &&
+ conf->from_offset > conf->to_offset)
+ return -EINVAL;
+
+retry:
+ ts_conf = textsearch_prepare(conf->algo, (u8 *) conf + sizeof(*conf),
+ conf->pattern_len, GFP_KERNEL, flags);
+
+ if (flags & TS_AUTOLOAD)
+ rtnl_lock();
+
+ if (IS_ERR(ts_conf)) {
+ if (PTR_ERR(ts_conf) == -ENOENT && !(flags & TS_AUTOLOAD)) {
+ rtnl_unlock();
+ flags |= TS_AUTOLOAD;
+ goto retry;
+ } else
+ return PTR_ERR(ts_conf);
+ } else if (flags & TS_AUTOLOAD) {
+ textsearch_destroy(ts_conf);
+ return -EAGAIN;
+ }
+
+ tm = kmalloc(sizeof(*tm), GFP_KERNEL);
+ if (tm == NULL) {
+ textsearch_destroy(ts_conf);
+ return -ENOBUFS;
+ }
+
+ tm->from_offset = conf->from_offset;
+ tm->to_offset = conf->to_offset;
+ tm->from_layer = conf->from_layer;
+ tm->to_layer = conf->to_layer;
+ tm->config = ts_conf;
+
+ m->datalen = sizeof(*tm);
+ m->data = (unsigned long) tm;
+
+ return 0;
+}
+
+static void em_text_destroy(struct tcf_proto *tp, struct tcf_ematch *m)
+{
+ textsearch_destroy(EM_TEXT_PRIV(m)->config);
+}
+
+static int em_text_dump(struct sk_buff *skb, struct tcf_ematch *m)
+{
+ struct text_match *tm = EM_TEXT_PRIV(m);
+ struct tcf_em_text conf;
+
+ strncpy(conf.algo, tm->config->ops->name, sizeof(conf.algo) - 1);
+ conf.from_offset = tm->from_offset;
+ conf.to_offset = tm->to_offset;
+ conf.from_layer = tm->from_layer;
+ conf.to_layer = tm->to_layer;
+ conf.pattern_len = textsearch_get_pattern_len(tm->config);
+ conf.pad = 0;
+
+ RTA_PUT_NOHDR(skb, sizeof(conf), &conf);
+ RTA_APPEND(skb, conf.pattern_len, textsearch_get_pattern(tm->config));
+ return 0;
+
+rtattr_failure:
+ return -1;
+}
+
+static struct tcf_ematch_ops em_text_ops = {
+ .kind = TCF_EM_TEXT,
+ .change = em_text_change,
+ .match = em_text_match,
+ .destroy = em_text_destroy,
+ .dump = em_text_dump,
+ .owner = THIS_MODULE,
+ .link = LIST_HEAD_INIT(em_text_ops.link)
+};
+
+static int __init init_em_text(void)
+{
+ return tcf_em_register(&em_text_ops);
+}
+
+static void __exit exit_em_text(void)
+{
+ tcf_em_unregister(&em_text_ops);
+}
+
+MODULE_LICENSE("GPL");
+
+module_init(init_em_text);
+module_exit(exit_em_text);