[linux-block.git] / net / ipv4 / metrics.c

// SPDX-License-Identifier: GPL-2.0-only
#include <linux/netlink.h>
#include <linux/nospec.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,
			      struct netlink_ext_ack *extack)
{
	bool ecn_ca = false;
	struct nlattr *nla;
	int remaining;

	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) {
			NL_SET_ERR_MSG(extack, "Invalid metric type");
			return -EINVAL;
		}

		type = array_index_nospec(type, RTAX_MAX + 1);
		if (type == RTAX_CC_ALGO) {
			char tmp[TCP_CA_NAME_MAX];

			nla_strscpy(tmp, nla, sizeof(tmp));
			val = tcp_ca_get_key_by_name(net, tmp, &ecn_ca);
			if (val == TCP_CA_UNSPEC) {
				NL_SET_ERR_MSG(extack, "Unknown tcp congestion algorithm");
				return -EINVAL;
			}
		} else {
			if (nla_len(nla) != sizeof(u32)) {
				NL_SET_ERR_MSG_ATTR(extack, nla,
						    "Invalid attribute in metrics");
				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)) {
			NL_SET_ERR_MSG(extack, "Unknown flag set in feature mask in metrics attribute");
			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 netlink_ext_ack *extack)
{
	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,
				 extack);
	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);
Commit	Line	Data
457c8996	1	// SPDX-License-Identifier: GPL-2.0-only
a919525a	2	#include <linux/netlink.h>
1d1d63b6	3	#include <linux/nospec.h>
a919525a DA	4	#include <linux/rtnetlink.h>
	5	#include <linux/types.h>
	6	#include <net/ip.h>
	7	#include <net/net_namespace.h>
	8	#include <net/tcp.h>
	9
767a2217	10	static int ip_metrics_convert(struct net net, struct nlattr fc_mx,
d7e774f3 DA	11	int fc_mx_len, u32 *metrics,
d7e774f3 DA	12	struct netlink_ext_ack *extack)
a919525a DA	13	{
	14	bool ecn_ca = false;
	15	struct nlattr *nla;
	16	int remaining;
	17
a919525a DA	18	nla_for_each_attr(nla, fc_mx, fc_mx_len, remaining) {
	19	int type = nla_type(nla);
	20	u32 val;
	21
	22	if (!type)
	23	continue;
d7e774f3 DA	24	if (type > RTAX_MAX) {
d7e774f3 DA	25	NL_SET_ERR_MSG(extack, "Invalid metric type");
a919525a	26	return -EINVAL;
d7e774f3	27	}
a919525a	28
1d1d63b6	29	type = array_index_nospec(type, RTAX_MAX + 1);
a919525a DA	30	if (type == RTAX_CC_ALGO) {
	31	char tmp[TCP_CA_NAME_MAX];
	32
872f6903	33	nla_strscpy(tmp, nla, sizeof(tmp));
a919525a	34	val = tcp_ca_get_key_by_name(net, tmp, &ecn_ca);
d7e774f3 DA	35	if (val == TCP_CA_UNSPEC) {
d7e774f3 DA	36	NL_SET_ERR_MSG(extack, "Unknown tcp congestion algorithm");
a919525a	37	return -EINVAL;
d7e774f3	38	}
a919525a	39	} else {
d7e774f3 DA	40	if (nla_len(nla) != sizeof(u32)) {
	41	NL_SET_ERR_MSG_ATTR(extack, nla,
	42	"Invalid attribute in metrics");
5b5e7a0d	43	return -EINVAL;
d7e774f3	44	}
a919525a DA	45	val = nla_get_u32(nla);
	46	}
	47	if (type == RTAX_ADVMSS && val > 65535 - 40)
	48	val = 65535 - 40;
	49	if (type == RTAX_MTU && val > 65535 - 15)
	50	val = 65535 - 15;
	51	if (type == RTAX_HOPLIMIT && val > 255)
	52	val = 255;
d7e774f3 DA	53	if (type == RTAX_FEATURES && (val & ~RTAX_FEATURE_MASK)) {
d7e774f3 DA	54	NL_SET_ERR_MSG(extack, "Unknown flag set in feature mask in metrics attribute");
a919525a	55	return -EINVAL;
d7e774f3	56	}
a919525a DA	57	metrics[type - 1] = val;
	58	}
	59
	60	if (ecn_ca)
	61	metrics[RTAX_FEATURES - 1] \|= DST_FEATURE_ECN_CA;
	62
	63	return 0;
	64	}
767a2217 DA	65
767a2217 DA	66	struct dst_metrics ip_fib_metrics_init(struct net net, struct nlattr *fc_mx,
d7e774f3 DA	67	int fc_mx_len,
d7e774f3 DA	68	struct netlink_ext_ack *extack)
767a2217 DA	69	{
	70	struct dst_metrics *fib_metrics;
	71	int err;
	72
	73	if (!fc_mx)
	74	return (struct dst_metrics *)&dst_default_metrics;
	75
	76	fib_metrics = kzalloc(sizeof(*fib_metrics), GFP_KERNEL);
	77	if (unlikely(!fib_metrics))
	78	return ERR_PTR(-ENOMEM);
	79
d7e774f3 DA	80	err = ip_metrics_convert(net, fc_mx, fc_mx_len, fib_metrics->metrics,
d7e774f3 DA	81	extack);
767a2217 DA	82	if (!err) {
	83	refcount_set(&fib_metrics->refcnt, 1);
	84	} else {
	85	kfree(fib_metrics);
	86	fib_metrics = ERR_PTR(err);
	87	}
	88
	89	return fib_metrics;
	90	}
	91	EXPORT_SYMBOL_GPL(ip_fib_metrics_init);