diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /net/sched/em_cmp.c |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'net/sched/em_cmp.c')
-rw-r--r-- | net/sched/em_cmp.c | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/net/sched/em_cmp.c b/net/sched/em_cmp.c new file mode 100644 index 000000000000..bf1f00f8b1bf --- /dev/null +++ b/net/sched/em_cmp.c @@ -0,0 +1,101 @@ +/* + * net/sched/em_cmp.c Simple packet data comparison 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/skbuff.h> +#include <linux/tc_ematch/tc_em_cmp.h> +#include <net/pkt_cls.h> + +static inline int cmp_needs_transformation(struct tcf_em_cmp *cmp) +{ + return unlikely(cmp->flags & TCF_EM_CMP_TRANS); +} + +static int em_cmp_match(struct sk_buff *skb, struct tcf_ematch *em, + struct tcf_pkt_info *info) +{ + struct tcf_em_cmp *cmp = (struct tcf_em_cmp *) em->data; + unsigned char *ptr = tcf_get_base_ptr(skb, cmp->layer) + cmp->off; + u32 val = 0; + + if (!tcf_valid_offset(skb, ptr, cmp->align)) + return 0; + + switch (cmp->align) { + case TCF_EM_ALIGN_U8: + val = *ptr; + break; + + case TCF_EM_ALIGN_U16: + val = *ptr << 8; + val |= *(ptr+1); + + if (cmp_needs_transformation(cmp)) + val = be16_to_cpu(val); + break; + + case TCF_EM_ALIGN_U32: + /* Worth checking boundries? The branching seems + * to get worse. Visit again. */ + val = *ptr << 24; + val |= *(ptr+1) << 16; + val |= *(ptr+2) << 8; + val |= *(ptr+3); + + if (cmp_needs_transformation(cmp)) + val = be32_to_cpu(val); + break; + + default: + return 0; + } + + if (cmp->mask) + val &= cmp->mask; + + switch (cmp->opnd) { + case TCF_EM_OPND_EQ: + return val == cmp->val; + case TCF_EM_OPND_LT: + return val < cmp->val; + case TCF_EM_OPND_GT: + return val > cmp->val; + } + + return 0; +} + +static struct tcf_ematch_ops em_cmp_ops = { + .kind = TCF_EM_CMP, + .datalen = sizeof(struct tcf_em_cmp), + .match = em_cmp_match, + .owner = THIS_MODULE, + .link = LIST_HEAD_INIT(em_cmp_ops.link) +}; + +static int __init init_em_cmp(void) +{ + return tcf_em_register(&em_cmp_ops); +} + +static void __exit exit_em_cmp(void) +{ + tcf_em_unregister(&em_cmp_ops); +} + +MODULE_LICENSE("GPL"); + +module_init(init_em_cmp); +module_exit(exit_em_cmp); + |