diff options
Diffstat (limited to 'net/sched/em_nbyte.c')
-rw-r--r-- | net/sched/em_nbyte.c | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/net/sched/em_nbyte.c b/net/sched/em_nbyte.c new file mode 100644 index 00000000000..71ea926a9f0 --- /dev/null +++ b/net/sched/em_nbyte.c @@ -0,0 +1,82 @@ +/* + * net/sched/em_nbyte.c N-Byte 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/tc_ematch/tc_em_nbyte.h> +#include <net/pkt_cls.h> + +struct nbyte_data +{ + struct tcf_em_nbyte hdr; + char pattern[0]; +}; + +static int em_nbyte_change(struct tcf_proto *tp, void *data, int data_len, + struct tcf_ematch *em) +{ + struct tcf_em_nbyte *nbyte = data; + + if (data_len < sizeof(*nbyte) || + data_len < (sizeof(*nbyte) + nbyte->len)) + return -EINVAL; + + em->datalen = sizeof(*nbyte) + nbyte->len; + em->data = (unsigned long) kmalloc(em->datalen, GFP_KERNEL); + if (em->data == 0UL) + return -ENOBUFS; + + memcpy((void *) em->data, data, em->datalen); + + return 0; +} + +static int em_nbyte_match(struct sk_buff *skb, struct tcf_ematch *em, + struct tcf_pkt_info *info) +{ + struct nbyte_data *nbyte = (struct nbyte_data *) em->data; + unsigned char *ptr = tcf_get_base_ptr(skb, nbyte->hdr.layer); + + ptr += nbyte->hdr.off; + + if (!tcf_valid_offset(skb, ptr, nbyte->hdr.len)) + return 0; + + return !memcmp(ptr + nbyte->hdr.off, nbyte->pattern, nbyte->hdr.len); +} + +static struct tcf_ematch_ops em_nbyte_ops = { + .kind = TCF_EM_NBYTE, + .change = em_nbyte_change, + .match = em_nbyte_match, + .owner = THIS_MODULE, + .link = LIST_HEAD_INIT(em_nbyte_ops.link) +}; + +static int __init init_em_nbyte(void) +{ + return tcf_em_register(&em_nbyte_ops); +} + +static void __exit exit_em_nbyte(void) +{ + tcf_em_unregister(&em_nbyte_ops); +} + +MODULE_LICENSE("GPL"); + +module_init(init_em_nbyte); +module_exit(exit_em_nbyte); |