diff --git a/MAINTAINERS b/MAINTAINERS index 3c84a8fecc09..d76fccd09266 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -9957,6 +9957,13 @@ L: linuxppc-dev@lists.ozlabs.org S: Maintained F: drivers/block/ps3vram.c +PSAMPLE PACKET SAMPLING SUPPORT: +M: Yotam Gigi +S: Maintained +F: net/psample +F: include/net/psample.h +F: include/uapi/linux/psample.h + PSTORE FILESYSTEM M: Anton Vorontsov M: Colin Cross diff --git a/include/net/psample.h b/include/net/psample.h new file mode 100644 index 000000000000..8888b0e1a82e --- /dev/null +++ b/include/net/psample.h @@ -0,0 +1,36 @@ +#ifndef __NET_PSAMPLE_H +#define __NET_PSAMPLE_H + +#include +#include +#include + +struct psample_group { + struct list_head list; + struct net *net; + u32 group_num; + u32 refcount; + u32 seq; +}; + +struct psample_group *psample_group_get(struct net *net, u32 group_num); +void psample_group_put(struct psample_group *group); + +#if IS_ENABLED(CONFIG_PSAMPLE) + +void psample_sample_packet(struct psample_group *group, struct sk_buff *skb, + u32 trunc_size, int in_ifindex, int out_ifindex, + u32 sample_rate); + +#else + +static inline void psample_sample_packet(struct psample_group *group, + struct sk_buff *skb, u32 trunc_size, + int in_ifindex, int out_ifindex, + u32 sample_rate) +{ +} + +#endif + +#endif /* __NET_PSAMPLE_H */ diff --git a/include/uapi/linux/Kbuild b/include/uapi/linux/Kbuild index e600b50be77e..80ad741a42fa 100644 --- a/include/uapi/linux/Kbuild +++ b/include/uapi/linux/Kbuild @@ -305,6 +305,7 @@ header-y += netrom.h header-y += net_namespace.h header-y += net_tstamp.h header-y += nfc.h +header-y += psample.h header-y += nfs2.h header-y += nfs3.h header-y += nfs4.h diff --git a/include/uapi/linux/psample.h b/include/uapi/linux/psample.h new file mode 100644 index 000000000000..ed48996ec0e8 --- /dev/null +++ b/include/uapi/linux/psample.h @@ -0,0 +1,35 @@ +#ifndef __UAPI_PSAMPLE_H +#define __UAPI_PSAMPLE_H + +enum { + /* sampled packet metadata */ + PSAMPLE_ATTR_IIFINDEX, + PSAMPLE_ATTR_OIFINDEX, + PSAMPLE_ATTR_ORIGSIZE, + PSAMPLE_ATTR_SAMPLE_GROUP, + PSAMPLE_ATTR_GROUP_SEQ, + PSAMPLE_ATTR_SAMPLE_RATE, + PSAMPLE_ATTR_DATA, + + /* commands attributes */ + PSAMPLE_ATTR_GROUP_REFCOUNT, + + __PSAMPLE_ATTR_MAX +}; + +enum psample_command { + PSAMPLE_CMD_SAMPLE, + PSAMPLE_CMD_GET_GROUP, + PSAMPLE_CMD_NEW_GROUP, + PSAMPLE_CMD_DEL_GROUP, +}; + +/* Can be overridden at runtime by module option */ +#define PSAMPLE_ATTR_MAX (__PSAMPLE_ATTR_MAX - 1) + +#define PSAMPLE_NL_MCGRP_CONFIG_NAME "config" +#define PSAMPLE_NL_MCGRP_SAMPLE_NAME "packets" +#define PSAMPLE_GENL_NAME "psample" +#define PSAMPLE_GENL_VERSION 1 + +#endif diff --git a/net/Kconfig b/net/Kconfig index 92ae1500d9e1..ce4aee69fc0d 100644 --- a/net/Kconfig +++ b/net/Kconfig @@ -390,6 +390,7 @@ source "net/9p/Kconfig" source "net/caif/Kconfig" source "net/ceph/Kconfig" source "net/nfc/Kconfig" +source "net/psample/Kconfig" config LWTUNNEL bool "Network light weight tunnels" diff --git a/net/Makefile b/net/Makefile index 5d6e0e5ff7f8..7d41de48310e 100644 --- a/net/Makefile +++ b/net/Makefile @@ -70,6 +70,7 @@ obj-$(CONFIG_DNS_RESOLVER) += dns_resolver/ obj-$(CONFIG_CEPH_LIB) += ceph/ obj-$(CONFIG_BATMAN_ADV) += batman-adv/ obj-$(CONFIG_NFC) += nfc/ +obj-$(CONFIG_PSAMPLE) += psample/ obj-$(CONFIG_OPENVSWITCH) += openvswitch/ obj-$(CONFIG_VSOCKETS) += vmw_vsock/ obj-$(CONFIG_MPLS) += mpls/ diff --git a/net/psample/Kconfig b/net/psample/Kconfig new file mode 100644 index 000000000000..d850246a6059 --- /dev/null +++ b/net/psample/Kconfig @@ -0,0 +1,15 @@ +# +# 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 000000000000..609b0a79c9f3 --- /dev/null +++ b/net/psample/Makefile @@ -0,0 +1,5 @@ +# +# 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 000000000000..8aa58a918783 --- /dev/null +++ b/net/psample/psample.c @@ -0,0 +1,301 @@ +/* + * net/psample/psample.c - Netlink channel for packet sampling + * Copyright (c) 2017 Yotam Gigi + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#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 }, +}; + +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(&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(&psample_groups_lock); + cb->args[0] = idx; + return msg->len; +} + +static const struct genl_ops psample_nl_ops[] = { + { + .cmd = PSAMPLE_CMD_GET_GROUP, + .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, + .ops = psample_nl_ops, + .n_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(group); +} + +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(&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(&psample_groups_lock); + return group; +} +EXPORT_SYMBOL_GPL(psample_group_get); + +void psample_group_put(struct psample_group *group) +{ + spin_lock(&psample_groups_lock); + + if (--group->refcount == 0) + psample_group_destroy(group); + + spin_unlock(&psample_groups_lock); +} +EXPORT_SYMBOL_GPL(psample_group_put); + +void psample_sample_packet(struct psample_group *group, struct sk_buff *skb, + u32 trunc_size, int in_ifindex, int out_ifindex, + u32 sample_rate) +{ + 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 */ + + 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 + 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 = (struct nlattr *)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; + } + + 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 "); +MODULE_DESCRIPTION("netlink channel for packet sampling"); +MODULE_LICENSE("GPL v2");