cmp.c

/* SPDX-License-Identifier: LGPL-2.1-only */
/*
 * Copyright (c) 2008-2013 Thomas Graf <tgraf@suug.ch>
 */
 
/**
 * @ingroup ematch
 * @defgroup em_cmp Simple packet data comparison
 *
 * @{
 */
 
#include <netlink-private/netlink.h>
#include <netlink-private/tc.h>
#include <netlink/netlink.h>
#include <netlink/route/cls/ematch.h>
#include <netlink/route/cls/ematch/cmp.h>
#include <linux/tc_ematch/tc_em_cmp.h>
 
void rtnl_ematch_cmp_set(struct rtnl_ematch *e, struct tcf_em_cmp *cfg)
{
        memcpy(rtnl_ematch_data(e), cfg, sizeof(*cfg));
}
 
struct tcf_em_cmp *rtnl_ematch_cmp_get(struct rtnl_ematch *e)
{
        return rtnl_ematch_data(e);
}
 
static int cmp_parse(struct rtnl_ematch *e, void *data, size_t len)
{
        memcpy(rtnl_ematch_data(e), data, len);
 
        return 0;
}
 
static const char *align_txt[] = {
        [TCF_EM_ALIGN_U8] = "u8",
        [TCF_EM_ALIGN_U16] = "u16",
        [TCF_EM_ALIGN_U32] = "u32"
};
 
static const char *layer_txt[] = {
        [TCF_LAYER_LINK] = "eth",
        [TCF_LAYER_NETWORK] = "ip",
        [TCF_LAYER_TRANSPORT] = "tcp"
};
 
static const char *operand_txt[] = {
        [TCF_EM_OPND_EQ] = "=",
        [TCF_EM_OPND_LT] = "<",
        [TCF_EM_OPND_GT] = ">",
};
 
static void cmp_dump(struct rtnl_ematch *e, struct nl_dump_params *p)
{
        struct tcf_em_cmp *cmp = rtnl_ematch_data(e);
 
        if (cmp->flags & TCF_EM_CMP_TRANS)
                nl_dump(p, "ntoh%c(", (cmp->align == TCF_EM_ALIGN_U32) ? 'l' : 's');
 
        nl_dump(p, "%s at %s+%u",
                align_txt[cmp->align], layer_txt[cmp->layer], cmp->off);
 
        if (cmp->mask)
                nl_dump(p, " & 0x%x", cmp->mask);
 
        if (cmp->flags & TCF_EM_CMP_TRANS)
                nl_dump(p, ")");
 
        nl_dump(p, " %s %u", operand_txt[cmp->opnd], cmp->val);
}
 
static struct rtnl_ematch_ops cmp_ops = {
        .eo_kind        = TCF_EM_CMP,
        .eo_name        = "cmp",
        .eo_minlen      = sizeof(struct tcf_em_cmp),
        .eo_datalen     = sizeof(struct tcf_em_cmp),
        .eo_parse       = cmp_parse,
        .eo_dump        = cmp_dump,
};
 
static void __init cmp_init(void)
{
        rtnl_ematch_register(&cmp_ops);
}
 
/** @} */