diff options
Diffstat (limited to 'net/l2tp/l2tp_netlink.c')
| -rw-r--r-- | net/l2tp/l2tp_netlink.c | 1048 |
1 files changed, 1048 insertions, 0 deletions
diff --git a/net/l2tp/l2tp_netlink.c b/net/l2tp/l2tp_netlink.c new file mode 100644 index 000000000..a901fd14f --- /dev/null +++ b/net/l2tp/l2tp_netlink.c @@ -0,0 +1,1048 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* L2TP netlink layer, for management + * + * Copyright (c) 2008,2009,2010 Katalix Systems Ltd + * + * Partly based on the IrDA nelink implementation + * (see net/irda/irnetlink.c) which is: + * Copyright (c) 2007 Samuel Ortiz <samuel@sortiz.org> + * which is in turn partly based on the wireless netlink code: + * Copyright 2006 Johannes Berg <johannes@sipsolutions.net> + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <net/sock.h> +#include <net/genetlink.h> +#include <net/udp.h> +#include <linux/in.h> +#include <linux/udp.h> +#include <linux/socket.h> +#include <linux/module.h> +#include <linux/list.h> +#include <net/net_namespace.h> + +#include <linux/l2tp.h> + +#include "l2tp_core.h" + +static struct genl_family l2tp_nl_family; + +static const struct genl_multicast_group l2tp_multicast_group[] = { + { + .name = L2TP_GENL_MCGROUP, + }, +}; + +static int l2tp_nl_tunnel_send(struct sk_buff *skb, u32 portid, u32 seq, + int flags, struct l2tp_tunnel *tunnel, u8 cmd); +static int l2tp_nl_session_send(struct sk_buff *skb, u32 portid, u32 seq, + int flags, struct l2tp_session *session, + u8 cmd); + +/* Accessed under genl lock */ +static const struct l2tp_nl_cmd_ops *l2tp_nl_cmd_ops[__L2TP_PWTYPE_MAX]; + +static struct l2tp_session *l2tp_nl_session_get(struct genl_info *info) +{ + u32 tunnel_id; + u32 session_id; + char *ifname; + struct l2tp_tunnel *tunnel; + struct l2tp_session *session = NULL; + struct net *net = genl_info_net(info); + + if (info->attrs[L2TP_ATTR_IFNAME]) { + ifname = nla_data(info->attrs[L2TP_ATTR_IFNAME]); + session = l2tp_session_get_by_ifname(net, ifname); + } else if ((info->attrs[L2TP_ATTR_SESSION_ID]) && + (info->attrs[L2TP_ATTR_CONN_ID])) { + tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]); + session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]); + tunnel = l2tp_tunnel_get(net, tunnel_id); + if (tunnel) { + session = l2tp_tunnel_get_session(tunnel, session_id); + l2tp_tunnel_dec_refcount(tunnel); + } + } + + return session; +} + +static int l2tp_nl_cmd_noop(struct sk_buff *skb, struct genl_info *info) +{ + struct sk_buff *msg; + void *hdr; + int ret = -ENOBUFS; + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) { + ret = -ENOMEM; + goto out; + } + + hdr = genlmsg_put(msg, info->snd_portid, info->snd_seq, + &l2tp_nl_family, 0, L2TP_CMD_NOOP); + if (!hdr) { + ret = -EMSGSIZE; + goto err_out; + } + + genlmsg_end(msg, hdr); + + return genlmsg_unicast(genl_info_net(info), msg, info->snd_portid); + +err_out: + nlmsg_free(msg); + +out: + return ret; +} + +static int l2tp_tunnel_notify(struct genl_family *family, + struct genl_info *info, + struct l2tp_tunnel *tunnel, + u8 cmd) +{ + struct sk_buff *msg; + int ret; + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) + return -ENOMEM; + + ret = l2tp_nl_tunnel_send(msg, info->snd_portid, info->snd_seq, + NLM_F_ACK, tunnel, cmd); + + if (ret >= 0) { + ret = genlmsg_multicast_allns(family, msg, 0, 0, GFP_ATOMIC); + /* We don't care if no one is listening */ + if (ret == -ESRCH) + ret = 0; + return ret; + } + + nlmsg_free(msg); + + return ret; +} + +static int l2tp_session_notify(struct genl_family *family, + struct genl_info *info, + struct l2tp_session *session, + u8 cmd) +{ + struct sk_buff *msg; + int ret; + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) + return -ENOMEM; + + ret = l2tp_nl_session_send(msg, info->snd_portid, info->snd_seq, + NLM_F_ACK, session, cmd); + + if (ret >= 0) { + ret = genlmsg_multicast_allns(family, msg, 0, 0, GFP_ATOMIC); + /* We don't care if no one is listening */ + if (ret == -ESRCH) + ret = 0; + return ret; + } + + nlmsg_free(msg); + + return ret; +} + +static int l2tp_nl_cmd_tunnel_create_get_addr(struct nlattr **attrs, struct l2tp_tunnel_cfg *cfg) +{ + if (attrs[L2TP_ATTR_UDP_SPORT]) + cfg->local_udp_port = nla_get_u16(attrs[L2TP_ATTR_UDP_SPORT]); + if (attrs[L2TP_ATTR_UDP_DPORT]) + cfg->peer_udp_port = nla_get_u16(attrs[L2TP_ATTR_UDP_DPORT]); + cfg->use_udp_checksums = nla_get_flag(attrs[L2TP_ATTR_UDP_CSUM]); + + /* Must have either AF_INET or AF_INET6 address for source and destination */ +#if IS_ENABLED(CONFIG_IPV6) + if (attrs[L2TP_ATTR_IP6_SADDR] && attrs[L2TP_ATTR_IP6_DADDR]) { + cfg->local_ip6 = nla_data(attrs[L2TP_ATTR_IP6_SADDR]); + cfg->peer_ip6 = nla_data(attrs[L2TP_ATTR_IP6_DADDR]); + cfg->udp6_zero_tx_checksums = nla_get_flag(attrs[L2TP_ATTR_UDP_ZERO_CSUM6_TX]); + cfg->udp6_zero_rx_checksums = nla_get_flag(attrs[L2TP_ATTR_UDP_ZERO_CSUM6_RX]); + return 0; + } +#endif + if (attrs[L2TP_ATTR_IP_SADDR] && attrs[L2TP_ATTR_IP_DADDR]) { + cfg->local_ip.s_addr = nla_get_in_addr(attrs[L2TP_ATTR_IP_SADDR]); + cfg->peer_ip.s_addr = nla_get_in_addr(attrs[L2TP_ATTR_IP_DADDR]); + return 0; + } + return -EINVAL; +} + +static int l2tp_nl_cmd_tunnel_create(struct sk_buff *skb, struct genl_info *info) +{ + u32 tunnel_id; + u32 peer_tunnel_id; + int proto_version; + int fd = -1; + int ret = 0; + struct l2tp_tunnel_cfg cfg = { 0, }; + struct l2tp_tunnel *tunnel; + struct net *net = genl_info_net(info); + struct nlattr **attrs = info->attrs; + + if (!attrs[L2TP_ATTR_CONN_ID]) { + ret = -EINVAL; + goto out; + } + tunnel_id = nla_get_u32(attrs[L2TP_ATTR_CONN_ID]); + + if (!attrs[L2TP_ATTR_PEER_CONN_ID]) { + ret = -EINVAL; + goto out; + } + peer_tunnel_id = nla_get_u32(attrs[L2TP_ATTR_PEER_CONN_ID]); + + if (!attrs[L2TP_ATTR_PROTO_VERSION]) { + ret = -EINVAL; + goto out; + } + proto_version = nla_get_u8(attrs[L2TP_ATTR_PROTO_VERSION]); + + if (!attrs[L2TP_ATTR_ENCAP_TYPE]) { + ret = -EINVAL; + goto out; + } + cfg.encap = nla_get_u16(attrs[L2TP_ATTR_ENCAP_TYPE]); + + /* Managed tunnels take the tunnel socket from userspace. + * Unmanaged tunnels must call out the source and destination addresses + * for the kernel to create the tunnel socket itself. + */ + if (attrs[L2TP_ATTR_FD]) { + fd = nla_get_u32(attrs[L2TP_ATTR_FD]); + } else { + ret = l2tp_nl_cmd_tunnel_create_get_addr(attrs, &cfg); + if (ret < 0) + goto out; + } + + ret = -EINVAL; + switch (cfg.encap) { + case L2TP_ENCAPTYPE_UDP: + case L2TP_ENCAPTYPE_IP: + ret = l2tp_tunnel_create(fd, proto_version, tunnel_id, + peer_tunnel_id, &cfg, &tunnel); + break; + } + + if (ret < 0) + goto out; + + l2tp_tunnel_inc_refcount(tunnel); + ret = l2tp_tunnel_register(tunnel, net, &cfg); + if (ret < 0) { + kfree(tunnel); + goto out; + } + ret = l2tp_tunnel_notify(&l2tp_nl_family, info, tunnel, + L2TP_CMD_TUNNEL_CREATE); + l2tp_tunnel_dec_refcount(tunnel); + +out: + return ret; +} + +static int l2tp_nl_cmd_tunnel_delete(struct sk_buff *skb, struct genl_info *info) +{ + struct l2tp_tunnel *tunnel; + u32 tunnel_id; + int ret = 0; + struct net *net = genl_info_net(info); + + if (!info->attrs[L2TP_ATTR_CONN_ID]) { + ret = -EINVAL; + goto out; + } + tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]); + + tunnel = l2tp_tunnel_get(net, tunnel_id); + if (!tunnel) { + ret = -ENODEV; + goto out; + } + + l2tp_tunnel_notify(&l2tp_nl_family, info, + tunnel, L2TP_CMD_TUNNEL_DELETE); + + l2tp_tunnel_delete(tunnel); + + l2tp_tunnel_dec_refcount(tunnel); + +out: + return ret; +} + +static int l2tp_nl_cmd_tunnel_modify(struct sk_buff *skb, struct genl_info *info) +{ + struct l2tp_tunnel *tunnel; + u32 tunnel_id; + int ret = 0; + struct net *net = genl_info_net(info); + + if (!info->attrs[L2TP_ATTR_CONN_ID]) { + ret = -EINVAL; + goto out; + } + tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]); + + tunnel = l2tp_tunnel_get(net, tunnel_id); + if (!tunnel) { + ret = -ENODEV; + goto out; + } + + ret = l2tp_tunnel_notify(&l2tp_nl_family, info, + tunnel, L2TP_CMD_TUNNEL_MODIFY); + + l2tp_tunnel_dec_refcount(tunnel); + +out: + return ret; +} + +#if IS_ENABLED(CONFIG_IPV6) +static int l2tp_nl_tunnel_send_addr6(struct sk_buff *skb, struct sock *sk, + enum l2tp_encap_type encap) +{ + struct inet_sock *inet = inet_sk(sk); + struct ipv6_pinfo *np = inet6_sk(sk); + + switch (encap) { + case L2TP_ENCAPTYPE_UDP: + if (udp_get_no_check6_tx(sk) && + nla_put_flag(skb, L2TP_ATTR_UDP_ZERO_CSUM6_TX)) + return -1; + if (udp_get_no_check6_rx(sk) && + nla_put_flag(skb, L2TP_ATTR_UDP_ZERO_CSUM6_RX)) + return -1; + if (nla_put_u16(skb, L2TP_ATTR_UDP_SPORT, ntohs(inet->inet_sport)) || + nla_put_u16(skb, L2TP_ATTR_UDP_DPORT, ntohs(inet->inet_dport))) + return -1; + fallthrough; + case L2TP_ENCAPTYPE_IP: + if (nla_put_in6_addr(skb, L2TP_ATTR_IP6_SADDR, &np->saddr) || + nla_put_in6_addr(skb, L2TP_ATTR_IP6_DADDR, &sk->sk_v6_daddr)) + return -1; + break; + } + return 0; +} +#endif + +static int l2tp_nl_tunnel_send_addr4(struct sk_buff *skb, struct sock *sk, + enum l2tp_encap_type encap) +{ + struct inet_sock *inet = inet_sk(sk); + + switch (encap) { + case L2TP_ENCAPTYPE_UDP: + if (nla_put_u8(skb, L2TP_ATTR_UDP_CSUM, !sk->sk_no_check_tx) || + nla_put_u16(skb, L2TP_ATTR_UDP_SPORT, ntohs(inet->inet_sport)) || + nla_put_u16(skb, L2TP_ATTR_UDP_DPORT, ntohs(inet->inet_dport))) + return -1; + fallthrough; + case L2TP_ENCAPTYPE_IP: + if (nla_put_in_addr(skb, L2TP_ATTR_IP_SADDR, inet->inet_saddr) || + nla_put_in_addr(skb, L2TP_ATTR_IP_DADDR, inet->inet_daddr)) + return -1; + break; + } + + return 0; +} + +/* Append attributes for the tunnel address, handling the different attribute types + * used for different tunnel encapsulation and AF_INET v.s. AF_INET6. + */ +static int l2tp_nl_tunnel_send_addr(struct sk_buff *skb, struct l2tp_tunnel *tunnel) +{ + struct sock *sk = tunnel->sock; + + if (!sk) + return 0; + +#if IS_ENABLED(CONFIG_IPV6) + if (sk->sk_family == AF_INET6) + return l2tp_nl_tunnel_send_addr6(skb, sk, tunnel->encap); +#endif + return l2tp_nl_tunnel_send_addr4(skb, sk, tunnel->encap); +} + +static int l2tp_nl_tunnel_send(struct sk_buff *skb, u32 portid, u32 seq, int flags, + struct l2tp_tunnel *tunnel, u8 cmd) +{ + void *hdr; + struct nlattr *nest; + + hdr = genlmsg_put(skb, portid, seq, &l2tp_nl_family, flags, cmd); + if (!hdr) + return -EMSGSIZE; + + if (nla_put_u8(skb, L2TP_ATTR_PROTO_VERSION, tunnel->version) || + nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) || + nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) || + nla_put_u32(skb, L2TP_ATTR_DEBUG, 0) || + nla_put_u16(skb, L2TP_ATTR_ENCAP_TYPE, tunnel->encap)) + goto nla_put_failure; + + nest = nla_nest_start_noflag(skb, L2TP_ATTR_STATS); + if (!nest) + goto nla_put_failure; + + if (nla_put_u64_64bit(skb, L2TP_ATTR_TX_PACKETS, + atomic_long_read(&tunnel->stats.tx_packets), + L2TP_ATTR_STATS_PAD) || + nla_put_u64_64bit(skb, L2TP_ATTR_TX_BYTES, + atomic_long_read(&tunnel->stats.tx_bytes), + L2TP_ATTR_STATS_PAD) || + nla_put_u64_64bit(skb, L2TP_ATTR_TX_ERRORS, + atomic_long_read(&tunnel->stats.tx_errors), + L2TP_ATTR_STATS_PAD) || + nla_put_u64_64bit(skb, L2TP_ATTR_RX_PACKETS, + atomic_long_read(&tunnel->stats.rx_packets), + L2TP_ATTR_STATS_PAD) || + nla_put_u64_64bit(skb, L2TP_ATTR_RX_BYTES, + atomic_long_read(&tunnel->stats.rx_bytes), + L2TP_ATTR_STATS_PAD) || + nla_put_u64_64bit(skb, L2TP_ATTR_RX_SEQ_DISCARDS, + atomic_long_read(&tunnel->stats.rx_seq_discards), + L2TP_ATTR_STATS_PAD) || + nla_put_u64_64bit(skb, L2TP_ATTR_RX_COOKIE_DISCARDS, + atomic_long_read(&tunnel->stats.rx_cookie_discards), + L2TP_ATTR_STATS_PAD) || + nla_put_u64_64bit(skb, L2TP_ATTR_RX_OOS_PACKETS, + atomic_long_read(&tunnel->stats.rx_oos_packets), + L2TP_ATTR_STATS_PAD) || + nla_put_u64_64bit(skb, L2TP_ATTR_RX_ERRORS, + atomic_long_read(&tunnel->stats.rx_errors), + L2TP_ATTR_STATS_PAD) || + nla_put_u64_64bit(skb, L2TP_ATTR_RX_INVALID, + atomic_long_read(&tunnel->stats.rx_invalid), + L2TP_ATTR_STATS_PAD)) + goto nla_put_failure; + nla_nest_end(skb, nest); + + if (l2tp_nl_tunnel_send_addr(skb, tunnel)) + goto nla_put_failure; + + genlmsg_end(skb, hdr); + return 0; + +nla_put_failure: + genlmsg_cancel(skb, hdr); + return -1; +} + +static int l2tp_nl_cmd_tunnel_get(struct sk_buff *skb, struct genl_info *info) +{ + struct l2tp_tunnel *tunnel; + struct sk_buff *msg; + u32 tunnel_id; + int ret = -ENOBUFS; + struct net *net = genl_info_net(info); + + if (!info->attrs[L2TP_ATTR_CONN_ID]) { + ret = -EINVAL; + goto err; + } + + tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]); + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) { + ret = -ENOMEM; + goto err; + } + + tunnel = l2tp_tunnel_get(net, tunnel_id); + if (!tunnel) { + ret = -ENODEV; + goto err_nlmsg; + } + + ret = l2tp_nl_tunnel_send(msg, info->snd_portid, info->snd_seq, + NLM_F_ACK, tunnel, L2TP_CMD_TUNNEL_GET); + if (ret < 0) + goto err_nlmsg_tunnel; + + l2tp_tunnel_dec_refcount(tunnel); + + return genlmsg_unicast(net, msg, info->snd_portid); + +err_nlmsg_tunnel: + l2tp_tunnel_dec_refcount(tunnel); +err_nlmsg: + nlmsg_free(msg); +err: + return ret; +} + +static int l2tp_nl_cmd_tunnel_dump(struct sk_buff *skb, struct netlink_callback *cb) +{ + int ti = cb->args[0]; + struct l2tp_tunnel *tunnel; + struct net *net = sock_net(skb->sk); + + for (;;) { + tunnel = l2tp_tunnel_get_nth(net, ti); + if (!tunnel) + goto out; + + if (l2tp_nl_tunnel_send(skb, NETLINK_CB(cb->skb).portid, + cb->nlh->nlmsg_seq, NLM_F_MULTI, + tunnel, L2TP_CMD_TUNNEL_GET) < 0) { + l2tp_tunnel_dec_refcount(tunnel); + goto out; + } + l2tp_tunnel_dec_refcount(tunnel); + + ti++; + } + +out: + cb->args[0] = ti; + + return skb->len; +} + +static int l2tp_nl_cmd_session_create(struct sk_buff *skb, struct genl_info *info) +{ + u32 tunnel_id = 0; + u32 session_id; + u32 peer_session_id; + int ret = 0; + struct l2tp_tunnel *tunnel; + struct l2tp_session *session; + struct l2tp_session_cfg cfg = { 0, }; + struct net *net = genl_info_net(info); + + if (!info->attrs[L2TP_ATTR_CONN_ID]) { + ret = -EINVAL; + goto out; + } + + tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]); + tunnel = l2tp_tunnel_get(net, tunnel_id); + if (!tunnel) { + ret = -ENODEV; + goto out; + } + + if (!info->attrs[L2TP_ATTR_SESSION_ID]) { + ret = -EINVAL; + goto out_tunnel; + } + session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]); + + if (!info->attrs[L2TP_ATTR_PEER_SESSION_ID]) { + ret = -EINVAL; + goto out_tunnel; + } + peer_session_id = nla_get_u32(info->attrs[L2TP_ATTR_PEER_SESSION_ID]); + + if (!info->attrs[L2TP_ATTR_PW_TYPE]) { + ret = -EINVAL; + goto out_tunnel; + } + cfg.pw_type = nla_get_u16(info->attrs[L2TP_ATTR_PW_TYPE]); + if (cfg.pw_type >= __L2TP_PWTYPE_MAX) { + ret = -EINVAL; + goto out_tunnel; + } + + /* L2TPv2 only accepts PPP pseudo-wires */ + if (tunnel->version == 2 && cfg.pw_type != L2TP_PWTYPE_PPP) { + ret = -EPROTONOSUPPORT; + goto out_tunnel; + } + + if (tunnel->version > 2) { + if (info->attrs[L2TP_ATTR_L2SPEC_TYPE]) { + cfg.l2specific_type = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_TYPE]); + if (cfg.l2specific_type != L2TP_L2SPECTYPE_DEFAULT && + cfg.l2specific_type != L2TP_L2SPECTYPE_NONE) { + ret = -EINVAL; + goto out_tunnel; + } + } else { + cfg.l2specific_type = L2TP_L2SPECTYPE_DEFAULT; + } + + if (info->attrs[L2TP_ATTR_COOKIE]) { + u16 len = nla_len(info->attrs[L2TP_ATTR_COOKIE]); + + if (len > 8) { + ret = -EINVAL; + goto out_tunnel; + } + cfg.cookie_len = len; + memcpy(&cfg.cookie[0], nla_data(info->attrs[L2TP_ATTR_COOKIE]), len); + } + if (info->attrs[L2TP_ATTR_PEER_COOKIE]) { + u16 len = nla_len(info->attrs[L2TP_ATTR_PEER_COOKIE]); + + if (len > 8) { + ret = -EINVAL; + goto out_tunnel; + } + cfg.peer_cookie_len = len; + memcpy(&cfg.peer_cookie[0], nla_data(info->attrs[L2TP_ATTR_PEER_COOKIE]), len); + } + if (info->attrs[L2TP_ATTR_IFNAME]) + cfg.ifname = nla_data(info->attrs[L2TP_ATTR_IFNAME]); + } + + if (info->attrs[L2TP_ATTR_RECV_SEQ]) + cfg.recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]); + + if (info->attrs[L2TP_ATTR_SEND_SEQ]) + cfg.send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]); + + if (info->attrs[L2TP_ATTR_LNS_MODE]) + cfg.lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]); + + if (info->attrs[L2TP_ATTR_RECV_TIMEOUT]) + cfg.reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]); + +#ifdef CONFIG_MODULES + if (!l2tp_nl_cmd_ops[cfg.pw_type]) { + genl_unlock(); + request_module("net-l2tp-type-%u", cfg.pw_type); + genl_lock(); + } +#endif + if (!l2tp_nl_cmd_ops[cfg.pw_type] || !l2tp_nl_cmd_ops[cfg.pw_type]->session_create) { + ret = -EPROTONOSUPPORT; + goto out_tunnel; + } + + ret = l2tp_nl_cmd_ops[cfg.pw_type]->session_create(net, tunnel, + session_id, + peer_session_id, + &cfg); + + if (ret >= 0) { + session = l2tp_tunnel_get_session(tunnel, session_id); + if (session) { + ret = l2tp_session_notify(&l2tp_nl_family, info, session, + L2TP_CMD_SESSION_CREATE); + l2tp_session_dec_refcount(session); + } + } + +out_tunnel: + l2tp_tunnel_dec_refcount(tunnel); +out: + return ret; +} + +static int l2tp_nl_cmd_session_delete(struct sk_buff *skb, struct genl_info *info) +{ + int ret = 0; + struct l2tp_session *session; + u16 pw_type; + + session = l2tp_nl_session_get(info); + if (!session) { + ret = -ENODEV; + goto out; + } + + l2tp_session_notify(&l2tp_nl_family, info, + session, L2TP_CMD_SESSION_DELETE); + + pw_type = session->pwtype; + if (pw_type < __L2TP_PWTYPE_MAX) + if (l2tp_nl_cmd_ops[pw_type] && l2tp_nl_cmd_ops[pw_type]->session_delete) + l2tp_nl_cmd_ops[pw_type]->session_delete(session); + + l2tp_session_dec_refcount(session); + +out: + return ret; +} + +static int l2tp_nl_cmd_session_modify(struct sk_buff *skb, struct genl_info *info) +{ + int ret = 0; + struct l2tp_session *session; + + session = l2tp_nl_session_get(info); + if (!session) { + ret = -ENODEV; + goto out; + } + + if (info->attrs[L2TP_ATTR_RECV_SEQ]) + session->recv_seq = nla_get_u8(info->attrs[L2TP_ATTR_RECV_SEQ]); + + if (info->attrs[L2TP_ATTR_SEND_SEQ]) { + session->send_seq = nla_get_u8(info->attrs[L2TP_ATTR_SEND_SEQ]); + l2tp_session_set_header_len(session, session->tunnel->version); + } + + if (info->attrs[L2TP_ATTR_LNS_MODE]) + session->lns_mode = nla_get_u8(info->attrs[L2TP_ATTR_LNS_MODE]); + + if (info->attrs[L2TP_ATTR_RECV_TIMEOUT]) + session->reorder_timeout = nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]); + + ret = l2tp_session_notify(&l2tp_nl_family, info, + session, L2TP_CMD_SESSION_MODIFY); + + l2tp_session_dec_refcount(session); + +out: + return ret; +} + +static int l2tp_nl_session_send(struct sk_buff *skb, u32 portid, u32 seq, int flags, + struct l2tp_session *session, u8 cmd) +{ + void *hdr; + struct nlattr *nest; + struct l2tp_tunnel *tunnel = session->tunnel; + + hdr = genlmsg_put(skb, portid, seq, &l2tp_nl_family, flags, cmd); + if (!hdr) + return -EMSGSIZE; + + if (nla_put_u32(skb, L2TP_ATTR_CONN_ID, tunnel->tunnel_id) || + nla_put_u32(skb, L2TP_ATTR_SESSION_ID, session->session_id) || + nla_put_u32(skb, L2TP_ATTR_PEER_CONN_ID, tunnel->peer_tunnel_id) || + nla_put_u32(skb, L2TP_ATTR_PEER_SESSION_ID, session->peer_session_id) || + nla_put_u32(skb, L2TP_ATTR_DEBUG, 0) || + nla_put_u16(skb, L2TP_ATTR_PW_TYPE, session->pwtype)) + goto nla_put_failure; + + if ((session->ifname[0] && + nla_put_string(skb, L2TP_ATTR_IFNAME, session->ifname)) || + (session->cookie_len && + nla_put(skb, L2TP_ATTR_COOKIE, session->cookie_len, session->cookie)) || + (session->peer_cookie_len && + nla_put(skb, L2TP_ATTR_PEER_COOKIE, session->peer_cookie_len, session->peer_cookie)) || + nla_put_u8(skb, L2TP_ATTR_RECV_SEQ, session->recv_seq) || + nla_put_u8(skb, L2TP_ATTR_SEND_SEQ, session->send_seq) || + nla_put_u8(skb, L2TP_ATTR_LNS_MODE, session->lns_mode) || + (l2tp_tunnel_uses_xfrm(tunnel) && + nla_put_u8(skb, L2TP_ATTR_USING_IPSEC, 1)) || + (session->reorder_timeout && + nla_put_msecs(skb, L2TP_ATTR_RECV_TIMEOUT, + session->reorder_timeout, L2TP_ATTR_PAD))) + goto nla_put_failure; + + nest = nla_nest_start_noflag(skb, L2TP_ATTR_STATS); + if (!nest) + goto nla_put_failure; + + if (nla_put_u64_64bit(skb, L2TP_ATTR_TX_PACKETS, + atomic_long_read(&session->stats.tx_packets), + L2TP_ATTR_STATS_PAD) || + nla_put_u64_64bit(skb, L2TP_ATTR_TX_BYTES, + atomic_long_read(&session->stats.tx_bytes), + L2TP_ATTR_STATS_PAD) || + nla_put_u64_64bit(skb, L2TP_ATTR_TX_ERRORS, + atomic_long_read(&session->stats.tx_errors), + L2TP_ATTR_STATS_PAD) || + nla_put_u64_64bit(skb, L2TP_ATTR_RX_PACKETS, + atomic_long_read(&session->stats.rx_packets), + L2TP_ATTR_STATS_PAD) || + nla_put_u64_64bit(skb, L2TP_ATTR_RX_BYTES, + atomic_long_read(&session->stats.rx_bytes), + L2TP_ATTR_STATS_PAD) || + nla_put_u64_64bit(skb, L2TP_ATTR_RX_SEQ_DISCARDS, + atomic_long_read(&session->stats.rx_seq_discards), + L2TP_ATTR_STATS_PAD) || + nla_put_u64_64bit(skb, L2TP_ATTR_RX_COOKIE_DISCARDS, + atomic_long_read(&session->stats.rx_cookie_discards), + L2TP_ATTR_STATS_PAD) || + nla_put_u64_64bit(skb, L2TP_ATTR_RX_OOS_PACKETS, + atomic_long_read(&session->stats.rx_oos_packets), + L2TP_ATTR_STATS_PAD) || + nla_put_u64_64bit(skb, L2TP_ATTR_RX_ERRORS, + atomic_long_read(&session->stats.rx_errors), + L2TP_ATTR_STATS_PAD) || + nla_put_u64_64bit(skb, L2TP_ATTR_RX_INVALID, + atomic_long_read(&session->stats.rx_invalid), + L2TP_ATTR_STATS_PAD)) + goto nla_put_failure; + nla_nest_end(skb, nest); + + genlmsg_end(skb, hdr); + return 0; + + nla_put_failure: + genlmsg_cancel(skb, hdr); + return -1; +} + +static int l2tp_nl_cmd_session_get(struct sk_buff *skb, struct genl_info *info) +{ + struct l2tp_session *session; + struct sk_buff *msg; + int ret; + + session = l2tp_nl_session_get(info); + if (!session) { + ret = -ENODEV; + goto err; + } + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) { + ret = -ENOMEM; + goto err_ref; + } + + ret = l2tp_nl_session_send(msg, info->snd_portid, info->snd_seq, + 0, session, L2TP_CMD_SESSION_GET); + if (ret < 0) + goto err_ref_msg; + + ret = genlmsg_unicast(genl_info_net(info), msg, info->snd_portid); + + l2tp_session_dec_refcount(session); + + return ret; + +err_ref_msg: + nlmsg_free(msg); +err_ref: + l2tp_session_dec_refcount(session); +err: + return ret; +} + +static int l2tp_nl_cmd_session_dump(struct sk_buff *skb, struct netlink_callback *cb) +{ + struct net *net = sock_net(skb->sk); + struct l2tp_session *session; + struct l2tp_tunnel *tunnel = NULL; + int ti = cb->args[0]; + int si = cb->args[1]; + + for (;;) { + if (!tunnel) { + tunnel = l2tp_tunnel_get_nth(net, ti); + if (!tunnel) + goto out; + } + + session = l2tp_session_get_nth(tunnel, si); + if (!session) { + ti++; + l2tp_tunnel_dec_refcount(tunnel); + tunnel = NULL; + si = 0; + continue; + } + + if (l2tp_nl_session_send(skb, NETLINK_CB(cb->skb).portid, + cb->nlh->nlmsg_seq, NLM_F_MULTI, + session, L2TP_CMD_SESSION_GET) < 0) { + l2tp_session_dec_refcount(session); + l2tp_tunnel_dec_refcount(tunnel); + break; + } + l2tp_session_dec_refcount(session); + + si++; + } + +out: + cb->args[0] = ti; + cb->args[1] = si; + + return skb->len; +} + +static const struct nla_policy l2tp_nl_policy[L2TP_ATTR_MAX + 1] = { + [L2TP_ATTR_NONE] = { .type = NLA_UNSPEC, }, + [L2TP_ATTR_PW_TYPE] = { .type = NLA_U16, }, + [L2TP_ATTR_ENCAP_TYPE] = { .type = NLA_U16, }, + [L2TP_ATTR_OFFSET] = { .type = NLA_U16, }, + [L2TP_ATTR_DATA_SEQ] = { .type = NLA_U8, }, + [L2TP_ATTR_L2SPEC_TYPE] = { .type = NLA_U8, }, + [L2TP_ATTR_L2SPEC_LEN] = { .type = NLA_U8, }, + [L2TP_ATTR_PROTO_VERSION] = { .type = NLA_U8, }, + [L2TP_ATTR_CONN_ID] = { .type = NLA_U32, }, + [L2TP_ATTR_PEER_CONN_ID] = { .type = NLA_U32, }, + [L2TP_ATTR_SESSION_ID] = { .type = NLA_U32, }, + [L2TP_ATTR_PEER_SESSION_ID] = { .type = NLA_U32, }, + [L2TP_ATTR_UDP_CSUM] = { .type = NLA_U8, }, + [L2TP_ATTR_VLAN_ID] = { .type = NLA_U16, }, + [L2TP_ATTR_DEBUG] = { .type = NLA_U32, }, + [L2TP_ATTR_RECV_SEQ] = { .type = NLA_U8, }, + [L2TP_ATTR_SEND_SEQ] = { .type = NLA_U8, }, + [L2TP_ATTR_LNS_MODE] = { .type = NLA_U8, }, + [L2TP_ATTR_USING_IPSEC] = { .type = NLA_U8, }, + [L2TP_ATTR_RECV_TIMEOUT] = { .type = NLA_MSECS, }, + [L2TP_ATTR_FD] = { .type = NLA_U32, }, + [L2TP_ATTR_IP_SADDR] = { .type = NLA_U32, }, + [L2TP_ATTR_IP_DADDR] = { .type = NLA_U32, }, + [L2TP_ATTR_UDP_SPORT] = { .type = NLA_U16, }, + [L2TP_ATTR_UDP_DPORT] = { .type = NLA_U16, }, + [L2TP_ATTR_MTU] = { .type = NLA_U16, }, + [L2TP_ATTR_MRU] = { .type = NLA_U16, }, + [L2TP_ATTR_STATS] = { .type = NLA_NESTED, }, + [L2TP_ATTR_IP6_SADDR] = { + .type = NLA_BINARY, + .len = sizeof(struct in6_addr), + }, + [L2TP_ATTR_IP6_DADDR] = { + .type = NLA_BINARY, + .len = sizeof(struct in6_addr), + }, + [L2TP_ATTR_IFNAME] = { + .type = NLA_NUL_STRING, + .len = IFNAMSIZ - 1, + }, + [L2TP_ATTR_COOKIE] = { + .type = NLA_BINARY, + .len = 8, + }, + [L2TP_ATTR_PEER_COOKIE] = { + .type = NLA_BINARY, + .len = 8, + }, +}; + +static const struct genl_small_ops l2tp_nl_ops[] = { + { + .cmd = L2TP_CMD_NOOP, + .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, + .doit = l2tp_nl_cmd_noop, + /* can be retrieved by unprivileged users */ + }, + { + .cmd = L2TP_CMD_TUNNEL_CREATE, + .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, + .doit = l2tp_nl_cmd_tunnel_create, + .flags = GENL_UNS_ADMIN_PERM, + }, + { + .cmd = L2TP_CMD_TUNNEL_DELETE, + .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, + .doit = l2tp_nl_cmd_tunnel_delete, + .flags = GENL_UNS_ADMIN_PERM, + }, + { + .cmd = L2TP_CMD_TUNNEL_MODIFY, + .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, + .doit = l2tp_nl_cmd_tunnel_modify, + .flags = GENL_UNS_ADMIN_PERM, + }, + { + .cmd = L2TP_CMD_TUNNEL_GET, + .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, + .doit = l2tp_nl_cmd_tunnel_get, + .dumpit = l2tp_nl_cmd_tunnel_dump, + .flags = GENL_UNS_ADMIN_PERM, + }, + { + .cmd = L2TP_CMD_SESSION_CREATE, + .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, + .doit = l2tp_nl_cmd_session_create, + .flags = GENL_UNS_ADMIN_PERM, + }, + { + .cmd = L2TP_CMD_SESSION_DELETE, + .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, + .doit = l2tp_nl_cmd_session_delete, + .flags = GENL_UNS_ADMIN_PERM, + }, + { + .cmd = L2TP_CMD_SESSION_MODIFY, + .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, + .doit = l2tp_nl_cmd_session_modify, + .flags = GENL_UNS_ADMIN_PERM, + }, + { + .cmd = L2TP_CMD_SESSION_GET, + .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, + .doit = l2tp_nl_cmd_session_get, + .dumpit = l2tp_nl_cmd_session_dump, + .flags = GENL_UNS_ADMIN_PERM, + }, +}; + +static struct genl_family l2tp_nl_family __ro_after_init = { + .name = L2TP_GENL_NAME, + .version = L2TP_GENL_VERSION, + .hdrsize = 0, + .maxattr = L2TP_ATTR_MAX, + .policy = l2tp_nl_policy, + .netnsok = true, + .module = THIS_MODULE, + .small_ops = l2tp_nl_ops, + .n_small_ops = ARRAY_SIZE(l2tp_nl_ops), + .resv_start_op = L2TP_CMD_SESSION_GET + 1, + .mcgrps = l2tp_multicast_group, + .n_mcgrps = ARRAY_SIZE(l2tp_multicast_group), +}; + +int l2tp_nl_register_ops(enum l2tp_pwtype pw_type, const struct l2tp_nl_cmd_ops *ops) +{ + int ret; + + ret = -EINVAL; + if (pw_type >= __L2TP_PWTYPE_MAX) + goto err; + + genl_lock(); + ret = -EBUSY; + if (l2tp_nl_cmd_ops[pw_type]) + goto out; + + l2tp_nl_cmd_ops[pw_type] = ops; + ret = 0; + +out: + genl_unlock(); +err: + return ret; +} +EXPORT_SYMBOL_GPL(l2tp_nl_register_ops); + +void l2tp_nl_unregister_ops(enum l2tp_pwtype pw_type) +{ + if (pw_type < __L2TP_PWTYPE_MAX) { + genl_lock(); + l2tp_nl_cmd_ops[pw_type] = NULL; + genl_unlock(); + } +} +EXPORT_SYMBOL_GPL(l2tp_nl_unregister_ops); + +static int __init l2tp_nl_init(void) +{ + pr_info("L2TP netlink interface\n"); + return genl_register_family(&l2tp_nl_family); +} + +static void l2tp_nl_cleanup(void) +{ + genl_unregister_family(&l2tp_nl_family); +} + +module_init(l2tp_nl_init); +module_exit(l2tp_nl_cleanup); + +MODULE_AUTHOR("James Chapman <jchapman@katalix.com>"); +MODULE_DESCRIPTION("L2TP netlink"); +MODULE_LICENSE("GPL"); +MODULE_VERSION("1.0"); +MODULE_ALIAS_GENL_FAMILY("l2tp"); |