Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

3 files changed, 495 insertions, 0 deletions

diff --git a/net/psample/Kconfig b/net/psample/Kconfig
new file mode 100644
index 000000000..028f514a9
--- /dev/null
+++ b/net/psample/Kconfig
@@ -0,0 +1,16 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# psample packet sampling configuration
+#
+
+menuconfig PSAMPLE
+	depends on NET
+	tristate "Packet-sampling netlink channel"
+	default n
+	help
+	  Say Y here to add support for packet-sampling netlink channel
+	  This netlink channel allows transferring packets alongside some
+	  metadata to userspace.
+
+	  To compile this support as a module, choose M here: the module will
+	  be called psample.
diff --git a/net/psample/Makefile b/net/psample/Makefile
new file mode 100644
index 000000000..a04367b9e
--- /dev/null
+++ b/net/psample/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Makefile for the psample netlink channel
+#
+
+obj-$(CONFIG_PSAMPLE) += psample.o
diff --git a/net/psample/psample.c b/net/psample/psample.c
new file mode 100644
index 000000000..5913da77c
--- /dev/null
+++ b/net/psample/psample.c
@@ -0,0 +1,473 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * net/psample/psample.c - Netlink channel for packet sampling
+ * Copyright (c) 2017 Yotam Gigi <yotamg@mellanox.com>
+ */
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/skbuff.h>
+#include <linux/module.h>
+#include <net/net_namespace.h>
+#include <net/sock.h>
+#include <net/netlink.h>
+#include <net/genetlink.h>
+#include <net/psample.h>
+#include <linux/spinlock.h>
+#include <net/ip_tunnels.h>
+#include <net/dst_metadata.h>
+
+#define PSAMPLE_MAX_PACKET_SIZE 0xffff
+
+static LIST_HEAD(psample_groups_list);
+static DEFINE_SPINLOCK(psample_groups_lock);
+
+/* multicast groups */
+enum psample_nl_multicast_groups {
+	PSAMPLE_NL_MCGRP_CONFIG,
+	PSAMPLE_NL_MCGRP_SAMPLE,
+};
+
+static const struct genl_multicast_group psample_nl_mcgrps[] = {
+	[PSAMPLE_NL_MCGRP_CONFIG] = { .name = PSAMPLE_NL_MCGRP_CONFIG_NAME },
+	[PSAMPLE_NL_MCGRP_SAMPLE] = { .name = PSAMPLE_NL_MCGRP_SAMPLE_NAME,
+				      .flags = GENL_UNS_ADMIN_PERM },
+};
+
+static struct genl_family psample_nl_family __ro_after_init;
+
+static int psample_group_nl_fill(struct sk_buff *msg,
+				 struct psample_group *group,
+				 enum psample_command cmd, u32 portid, u32 seq,
+				 int flags)
+{
+	void *hdr;
+	int ret;
+
+	hdr = genlmsg_put(msg, portid, seq, &psample_nl_family, flags, cmd);
+	if (!hdr)
+		return -EMSGSIZE;
+
+	ret = nla_put_u32(msg, PSAMPLE_ATTR_SAMPLE_GROUP, group->group_num);
+	if (ret < 0)
+		goto error;
+
+	ret = nla_put_u32(msg, PSAMPLE_ATTR_GROUP_REFCOUNT, group->refcount);
+	if (ret < 0)
+		goto error;
+
+	ret = nla_put_u32(msg, PSAMPLE_ATTR_GROUP_SEQ, group->seq);
+	if (ret < 0)
+		goto error;
+
+	genlmsg_end(msg, hdr);
+	return 0;
+
+error:
+	genlmsg_cancel(msg, hdr);
+	return -EMSGSIZE;
+}
+
+static int psample_nl_cmd_get_group_dumpit(struct sk_buff *msg,
+					   struct netlink_callback *cb)
+{
+	struct psample_group *group;
+	int start = cb->args[0];
+	int idx = 0;
+	int err;
+
+	spin_lock_bh(&psample_groups_lock);
+	list_for_each_entry(group, &psample_groups_list, list) {
+		if (!net_eq(group->net, sock_net(msg->sk)))
+			continue;
+		if (idx < start) {
+			idx++;
+			continue;
+		}
+		err = psample_group_nl_fill(msg, group, PSAMPLE_CMD_NEW_GROUP,
+					    NETLINK_CB(cb->skb).portid,
+					    cb->nlh->nlmsg_seq, NLM_F_MULTI);
+		if (err)
+			break;
+		idx++;
+	}
+
+	spin_unlock_bh(&psample_groups_lock);
+	cb->args[0] = idx;
+	return msg->len;
+}
+
+static const struct genl_small_ops psample_nl_ops[] = {
+	{
+		.cmd = PSAMPLE_CMD_GET_GROUP,
+		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
+		.dumpit = psample_nl_cmd_get_group_dumpit,
+		/* can be retrieved by unprivileged users */
+	}
+};
+
+static struct genl_family psample_nl_family __ro_after_init = {
+	.name		= PSAMPLE_GENL_NAME,
+	.version	= PSAMPLE_GENL_VERSION,
+	.maxattr	= PSAMPLE_ATTR_MAX,
+	.netnsok	= true,
+	.module		= THIS_MODULE,
+	.mcgrps		= psample_nl_mcgrps,
+	.small_ops	= psample_nl_ops,
+	.n_small_ops	= ARRAY_SIZE(psample_nl_ops),
+	.n_mcgrps	= ARRAY_SIZE(psample_nl_mcgrps),
+};
+
+static void psample_group_notify(struct psample_group *group,
+				 enum psample_command cmd)
+{
+	struct sk_buff *msg;
+	int err;
+
+	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
+	if (!msg)
+		return;
+
+	err = psample_group_nl_fill(msg, group, cmd, 0, 0, NLM_F_MULTI);
+	if (!err)
+		genlmsg_multicast_netns(&psample_nl_family, group->net, msg, 0,
+					PSAMPLE_NL_MCGRP_CONFIG, GFP_ATOMIC);
+	else
+		nlmsg_free(msg);
+}
+
+static struct psample_group *psample_group_create(struct net *net,
+						  u32 group_num)
+{
+	struct psample_group *group;
+
+	group = kzalloc(sizeof(*group), GFP_ATOMIC);
+	if (!group)
+		return NULL;
+
+	group->net = net;
+	group->group_num = group_num;
+	list_add_tail(&group->list, &psample_groups_list);
+
+	psample_group_notify(group, PSAMPLE_CMD_NEW_GROUP);
+	return group;
+}
+
+static void psample_group_destroy(struct psample_group *group)
+{
+	psample_group_notify(group, PSAMPLE_CMD_DEL_GROUP);
+	list_del(&group->list);
+	kfree_rcu(group, rcu);
+}
+
+static struct psample_group *
+psample_group_lookup(struct net *net, u32 group_num)
+{
+	struct psample_group *group;
+
+	list_for_each_entry(group, &psample_groups_list, list)
+		if ((group->group_num == group_num) && (group->net == net))
+			return group;
+	return NULL;
+}
+
+struct psample_group *psample_group_get(struct net *net, u32 group_num)
+{
+	struct psample_group *group;
+
+	spin_lock_bh(&psample_groups_lock);
+
+	group = psample_group_lookup(net, group_num);
+	if (!group) {
+		group = psample_group_create(net, group_num);
+		if (!group)
+			goto out;
+	}
+	group->refcount++;
+
+out:
+	spin_unlock_bh(&psample_groups_lock);
+	return group;
+}
+EXPORT_SYMBOL_GPL(psample_group_get);
+
+void psample_group_take(struct psample_group *group)
+{
+	spin_lock_bh(&psample_groups_lock);
+	group->refcount++;
+	spin_unlock_bh(&psample_groups_lock);
+}
+EXPORT_SYMBOL_GPL(psample_group_take);
+
+void psample_group_put(struct psample_group *group)
+{
+	spin_lock_bh(&psample_groups_lock);
+
+	if (--group->refcount == 0)
+		psample_group_destroy(group);
+
+	spin_unlock_bh(&psample_groups_lock);
+}
+EXPORT_SYMBOL_GPL(psample_group_put);
+
+#ifdef CONFIG_INET
+static int __psample_ip_tun_to_nlattr(struct sk_buff *skb,
+			      struct ip_tunnel_info *tun_info)
+{
+	unsigned short tun_proto = ip_tunnel_info_af(tun_info);
+	const void *tun_opts = ip_tunnel_info_opts(tun_info);
+	const struct ip_tunnel_key *tun_key = &tun_info->key;
+	int tun_opts_len = tun_info->options_len;
+
+	if (tun_key->tun_flags & TUNNEL_KEY &&
+	    nla_put_be64(skb, PSAMPLE_TUNNEL_KEY_ATTR_ID, tun_key->tun_id,
+			 PSAMPLE_TUNNEL_KEY_ATTR_PAD))
+		return -EMSGSIZE;
+
+	if (tun_info->mode & IP_TUNNEL_INFO_BRIDGE &&
+	    nla_put_flag(skb, PSAMPLE_TUNNEL_KEY_ATTR_IPV4_INFO_BRIDGE))
+		return -EMSGSIZE;
+
+	switch (tun_proto) {
+	case AF_INET:
+		if (tun_key->u.ipv4.src &&
+		    nla_put_in_addr(skb, PSAMPLE_TUNNEL_KEY_ATTR_IPV4_SRC,
+				    tun_key->u.ipv4.src))
+			return -EMSGSIZE;
+		if (tun_key->u.ipv4.dst &&
+		    nla_put_in_addr(skb, PSAMPLE_TUNNEL_KEY_ATTR_IPV4_DST,
+				    tun_key->u.ipv4.dst))
+			return -EMSGSIZE;
+		break;
+	case AF_INET6:
+		if (!ipv6_addr_any(&tun_key->u.ipv6.src) &&
+		    nla_put_in6_addr(skb, PSAMPLE_TUNNEL_KEY_ATTR_IPV6_SRC,
+				     &tun_key->u.ipv6.src))
+			return -EMSGSIZE;
+		if (!ipv6_addr_any(&tun_key->u.ipv6.dst) &&
+		    nla_put_in6_addr(skb, PSAMPLE_TUNNEL_KEY_ATTR_IPV6_DST,
+				     &tun_key->u.ipv6.dst))
+			return -EMSGSIZE;
+		break;
+	}
+	if (tun_key->tos &&
+	    nla_put_u8(skb, PSAMPLE_TUNNEL_KEY_ATTR_TOS, tun_key->tos))
+		return -EMSGSIZE;
+	if (nla_put_u8(skb, PSAMPLE_TUNNEL_KEY_ATTR_TTL, tun_key->ttl))
+		return -EMSGSIZE;
+	if ((tun_key->tun_flags & TUNNEL_DONT_FRAGMENT) &&
+	    nla_put_flag(skb, PSAMPLE_TUNNEL_KEY_ATTR_DONT_FRAGMENT))
+		return -EMSGSIZE;
+	if ((tun_key->tun_flags & TUNNEL_CSUM) &&
+	    nla_put_flag(skb, PSAMPLE_TUNNEL_KEY_ATTR_CSUM))
+		return -EMSGSIZE;
+	if (tun_key->tp_src &&
+	    nla_put_be16(skb, PSAMPLE_TUNNEL_KEY_ATTR_TP_SRC, tun_key->tp_src))
+		return -EMSGSIZE;
+	if (tun_key->tp_dst &&
+	    nla_put_be16(skb, PSAMPLE_TUNNEL_KEY_ATTR_TP_DST, tun_key->tp_dst))
+		return -EMSGSIZE;
+	if ((tun_key->tun_flags & TUNNEL_OAM) &&
+	    nla_put_flag(skb, PSAMPLE_TUNNEL_KEY_ATTR_OAM))
+		return -EMSGSIZE;
+	if (tun_opts_len) {
+		if (tun_key->tun_flags & TUNNEL_GENEVE_OPT &&
+		    nla_put(skb, PSAMPLE_TUNNEL_KEY_ATTR_GENEVE_OPTS,
+			    tun_opts_len, tun_opts))
+			return -EMSGSIZE;
+		else if (tun_key->tun_flags & TUNNEL_ERSPAN_OPT &&
+			 nla_put(skb, PSAMPLE_TUNNEL_KEY_ATTR_ERSPAN_OPTS,
+				 tun_opts_len, tun_opts))
+			return -EMSGSIZE;
+	}
+
+	return 0;
+}
+
+static int psample_ip_tun_to_nlattr(struct sk_buff *skb,
+			    struct ip_tunnel_info *tun_info)
+{
+	struct nlattr *nla;
+	int err;
+
+	nla = nla_nest_start_noflag(skb, PSAMPLE_ATTR_TUNNEL);
+	if (!nla)
+		return -EMSGSIZE;
+
+	err = __psample_ip_tun_to_nlattr(skb, tun_info);
+	if (err) {
+		nla_nest_cancel(skb, nla);
+		return err;
+	}
+
+	nla_nest_end(skb, nla);
+
+	return 0;
+}
+
+static int psample_tunnel_meta_len(struct ip_tunnel_info *tun_info)
+{
+	unsigned short tun_proto = ip_tunnel_info_af(tun_info);
+	const struct ip_tunnel_key *tun_key = &tun_info->key;
+	int tun_opts_len = tun_info->options_len;
+	int sum = nla_total_size(0);	/* PSAMPLE_ATTR_TUNNEL */
+
+	if (tun_key->tun_flags & TUNNEL_KEY)
+		sum += nla_total_size_64bit(sizeof(u64));
+
+	if (tun_info->mode & IP_TUNNEL_INFO_BRIDGE)
+		sum += nla_total_size(0);
+
+	switch (tun_proto) {
+	case AF_INET:
+		if (tun_key->u.ipv4.src)
+			sum += nla_total_size(sizeof(u32));
+		if (tun_key->u.ipv4.dst)
+			sum += nla_total_size(sizeof(u32));
+		break;
+	case AF_INET6:
+		if (!ipv6_addr_any(&tun_key->u.ipv6.src))
+			sum += nla_total_size(sizeof(struct in6_addr));
+		if (!ipv6_addr_any(&tun_key->u.ipv6.dst))
+			sum += nla_total_size(sizeof(struct in6_addr));
+		break;
+	}
+	if (tun_key->tos)
+		sum += nla_total_size(sizeof(u8));
+	sum += nla_total_size(sizeof(u8));	/* TTL */
+	if (tun_key->tun_flags & TUNNEL_DONT_FRAGMENT)
+		sum += nla_total_size(0);
+	if (tun_key->tun_flags & TUNNEL_CSUM)
+		sum += nla_total_size(0);
+	if (tun_key->tp_src)
+		sum += nla_total_size(sizeof(u16));
+	if (tun_key->tp_dst)
+		sum += nla_total_size(sizeof(u16));
+	if (tun_key->tun_flags & TUNNEL_OAM)
+		sum += nla_total_size(0);
+	if (tun_opts_len) {
+		if (tun_key->tun_flags & TUNNEL_GENEVE_OPT)
+			sum += nla_total_size(tun_opts_len);
+		else if (tun_key->tun_flags & TUNNEL_ERSPAN_OPT)
+			sum += nla_total_size(tun_opts_len);
+	}
+
+	return sum;
+}
+#endif
+
+void psample_sample_packet(struct psample_group *group, struct sk_buff *skb,
+			   u32 trunc_size, int in_ifindex, int out_ifindex,
+			   u32 sample_rate)
+{
+#ifdef CONFIG_INET
+	struct ip_tunnel_info *tun_info;
+#endif
+	struct sk_buff *nl_skb;
+	int data_len;
+	int meta_len;
+	void *data;
+	int ret;
+
+	meta_len = (in_ifindex ? nla_total_size(sizeof(u16)) : 0) +
+		   (out_ifindex ? nla_total_size(sizeof(u16)) : 0) +
+		   nla_total_size(sizeof(u32)) +	/* sample_rate */
+		   nla_total_size(sizeof(u32)) +	/* orig_size */
+		   nla_total_size(sizeof(u32)) +	/* group_num */
+		   nla_total_size(sizeof(u32));		/* seq */
+
+#ifdef CONFIG_INET
+	tun_info = skb_tunnel_info(skb);
+	if (tun_info)
+		meta_len += psample_tunnel_meta_len(tun_info);
+#endif
+
+	data_len = min(skb->len, trunc_size);
+	if (meta_len + nla_total_size(data_len) > PSAMPLE_MAX_PACKET_SIZE)
+		data_len = PSAMPLE_MAX_PACKET_SIZE - meta_len - NLA_HDRLEN
+			    - NLA_ALIGNTO;
+
+	nl_skb = genlmsg_new(meta_len + nla_total_size(data_len), GFP_ATOMIC);
+	if (unlikely(!nl_skb))
+		return;
+
+	data = genlmsg_put(nl_skb, 0, 0, &psample_nl_family, 0,
+			   PSAMPLE_CMD_SAMPLE);
+	if (unlikely(!data))
+		goto error;
+
+	if (in_ifindex) {
+		ret = nla_put_u16(nl_skb, PSAMPLE_ATTR_IIFINDEX, in_ifindex);
+		if (unlikely(ret < 0))
+			goto error;
+	}
+
+	if (out_ifindex) {
+		ret = nla_put_u16(nl_skb, PSAMPLE_ATTR_OIFINDEX, out_ifindex);
+		if (unlikely(ret < 0))
+			goto error;
+	}
+
+	ret = nla_put_u32(nl_skb, PSAMPLE_ATTR_SAMPLE_RATE, sample_rate);
+	if (unlikely(ret < 0))
+		goto error;
+
+	ret = nla_put_u32(nl_skb, PSAMPLE_ATTR_ORIGSIZE, skb->len);
+	if (unlikely(ret < 0))
+		goto error;
+
+	ret = nla_put_u32(nl_skb, PSAMPLE_ATTR_SAMPLE_GROUP, group->group_num);
+	if (unlikely(ret < 0))
+		goto error;
+
+	ret = nla_put_u32(nl_skb, PSAMPLE_ATTR_GROUP_SEQ, group->seq++);
+	if (unlikely(ret < 0))
+		goto error;
+
+	if (data_len) {
+		int nla_len = nla_total_size(data_len);
+		struct nlattr *nla;
+
+		nla = skb_put(nl_skb, nla_len);
+		nla->nla_type = PSAMPLE_ATTR_DATA;
+		nla->nla_len = nla_attr_size(data_len);
+
+		if (skb_copy_bits(skb, 0, nla_data(nla), data_len))
+			goto error;
+	}
+
+#ifdef CONFIG_INET
+	if (tun_info) {
+		ret = psample_ip_tun_to_nlattr(nl_skb, tun_info);
+		if (unlikely(ret < 0))
+			goto error;
+	}
+#endif
+
+	genlmsg_end(nl_skb, data);
+	genlmsg_multicast_netns(&psample_nl_family, group->net, nl_skb, 0,
+				PSAMPLE_NL_MCGRP_SAMPLE, GFP_ATOMIC);
+
+	return;
+error:
+	pr_err_ratelimited("Could not create psample log message\n");
+	nlmsg_free(nl_skb);
+}
+EXPORT_SYMBOL_GPL(psample_sample_packet);
+
+static int __init psample_module_init(void)
+{
+	return genl_register_family(&psample_nl_family);
+}
+
+static void __exit psample_module_exit(void)
+{
+	genl_unregister_family(&psample_nl_family);
+}
+
+module_init(psample_module_init);
+module_exit(psample_module_exit);
+
+MODULE_AUTHOR("Yotam Gigi <yotam.gi@gmail.com>");
+MODULE_DESCRIPTION("netlink channel for packet sampling");
+MODULE_LICENSE("GPL v2");