linux/net/ipv4/metrics.c

80 lines
1.7 KiB
C

#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#include <linux/types.h>
#include <net/ip.h>
#include <net/net_namespace.h>
#include <net/tcp.h>
static int ip_metrics_convert(struct net *net, struct nlattr *fc_mx,
int fc_mx_len, u32 *metrics)
{
bool ecn_ca = false;
struct nlattr *nla;
int remaining;
if (!fc_mx)
return 0;
nla_for_each_attr(nla, fc_mx, fc_mx_len, remaining) {
int type = nla_type(nla);
u32 val;
if (!type)
continue;
if (type > RTAX_MAX)
return -EINVAL;
if (type == RTAX_CC_ALGO) {
char tmp[TCP_CA_NAME_MAX];
nla_strlcpy(tmp, nla, sizeof(tmp));
val = tcp_ca_get_key_by_name(net, tmp, &ecn_ca);
if (val == TCP_CA_UNSPEC)
return -EINVAL;
} else {
if (nla_len(nla) != sizeof(u32))
return -EINVAL;
val = nla_get_u32(nla);
}
if (type == RTAX_ADVMSS && val > 65535 - 40)
val = 65535 - 40;
if (type == RTAX_MTU && val > 65535 - 15)
val = 65535 - 15;
if (type == RTAX_HOPLIMIT && val > 255)
val = 255;
if (type == RTAX_FEATURES && (val & ~RTAX_FEATURE_MASK))
return -EINVAL;
metrics[type - 1] = val;
}
if (ecn_ca)
metrics[RTAX_FEATURES - 1] |= DST_FEATURE_ECN_CA;
return 0;
}
struct dst_metrics *ip_fib_metrics_init(struct net *net, struct nlattr *fc_mx,
int fc_mx_len)
{
struct dst_metrics *fib_metrics;
int err;
if (!fc_mx)
return (struct dst_metrics *)&dst_default_metrics;
fib_metrics = kzalloc(sizeof(*fib_metrics), GFP_KERNEL);
if (unlikely(!fib_metrics))
return ERR_PTR(-ENOMEM);
err = ip_metrics_convert(net, fc_mx, fc_mx_len, fib_metrics->metrics);
if (!err) {
refcount_set(&fib_metrics->refcnt, 1);
} else {
kfree(fib_metrics);
fib_metrics = ERR_PTR(err);
}
return fib_metrics;
}
EXPORT_SYMBOL_GPL(ip_fib_metrics_init);