linux/net/mptcp/pm_userspace.c
Matthieu Baerts (NGI0) b83fbca1b4 mptcp: pm: reduce entries iterations on connect
__mptcp_subflow_connect() is currently called from the path-managers,
which have all the required information to create subflows. No need to
call the PM again to re-iterate over the list of entries with RCU lock
to get more info.

Instead, it is possible to pass a mptcp_pm_addr_entry structure, instead
of a mptcp_addr_info one. The former contains the ifindex and the flags
that are required when creating the new subflow.

This is a partial revert of commit ee285257a9 ("mptcp: drop flags and
ifindex arguments").

While at it, the local ID can also be set if it is known and 0, to avoid
having to set it in the 'rebuild_header' hook, which will cause a new
iteration of the endpoint entries.

Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20240902-net-next-mptcp-mib-mpjtx-misc-v1-2-d3e0f3773b90@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-09-03 15:25:42 -07:00

745 lines
18 KiB
C

// SPDX-License-Identifier: GPL-2.0
/* Multipath TCP
*
* Copyright (c) 2022, Intel Corporation.
*/
#include "protocol.h"
#include "mib.h"
#include "mptcp_pm_gen.h"
void mptcp_free_local_addr_list(struct mptcp_sock *msk)
{
struct mptcp_pm_addr_entry *entry, *tmp;
struct sock *sk = (struct sock *)msk;
LIST_HEAD(free_list);
if (!mptcp_pm_is_userspace(msk))
return;
spin_lock_bh(&msk->pm.lock);
list_splice_init(&msk->pm.userspace_pm_local_addr_list, &free_list);
spin_unlock_bh(&msk->pm.lock);
list_for_each_entry_safe(entry, tmp, &free_list, list) {
sock_kfree_s(sk, entry, sizeof(*entry));
}
}
static int mptcp_userspace_pm_append_new_local_addr(struct mptcp_sock *msk,
struct mptcp_pm_addr_entry *entry,
bool needs_id)
{
DECLARE_BITMAP(id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1);
struct mptcp_pm_addr_entry *match = NULL;
struct sock *sk = (struct sock *)msk;
struct mptcp_pm_addr_entry *e;
bool addr_match = false;
bool id_match = false;
int ret = -EINVAL;
bitmap_zero(id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1);
spin_lock_bh(&msk->pm.lock);
list_for_each_entry(e, &msk->pm.userspace_pm_local_addr_list, list) {
addr_match = mptcp_addresses_equal(&e->addr, &entry->addr, true);
if (addr_match && entry->addr.id == 0 && needs_id)
entry->addr.id = e->addr.id;
id_match = (e->addr.id == entry->addr.id);
if (addr_match && id_match) {
match = e;
break;
} else if (addr_match || id_match) {
break;
}
__set_bit(e->addr.id, id_bitmap);
}
if (!match && !addr_match && !id_match) {
/* Memory for the entry is allocated from the
* sock option buffer.
*/
e = sock_kmalloc(sk, sizeof(*e), GFP_ATOMIC);
if (!e) {
ret = -ENOMEM;
goto append_err;
}
*e = *entry;
if (!e->addr.id && needs_id)
e->addr.id = find_next_zero_bit(id_bitmap,
MPTCP_PM_MAX_ADDR_ID + 1,
1);
list_add_tail_rcu(&e->list, &msk->pm.userspace_pm_local_addr_list);
msk->pm.local_addr_used++;
ret = e->addr.id;
} else if (match) {
ret = entry->addr.id;
}
append_err:
spin_unlock_bh(&msk->pm.lock);
return ret;
}
/* If the subflow is closed from the other peer (not via a
* subflow destroy command then), we want to keep the entry
* not to assign the same ID to another address and to be
* able to send RM_ADDR after the removal of the subflow.
*/
static int mptcp_userspace_pm_delete_local_addr(struct mptcp_sock *msk,
struct mptcp_pm_addr_entry *addr)
{
struct mptcp_pm_addr_entry *entry, *tmp;
list_for_each_entry_safe(entry, tmp, &msk->pm.userspace_pm_local_addr_list, list) {
if (mptcp_addresses_equal(&entry->addr, &addr->addr, false)) {
/* TODO: a refcount is needed because the entry can
* be used multiple times (e.g. fullmesh mode).
*/
list_del_rcu(&entry->list);
kfree(entry);
msk->pm.local_addr_used--;
return 0;
}
}
return -EINVAL;
}
static struct mptcp_pm_addr_entry *
mptcp_userspace_pm_lookup_addr_by_id(struct mptcp_sock *msk, unsigned int id)
{
struct mptcp_pm_addr_entry *entry;
list_for_each_entry(entry, &msk->pm.userspace_pm_local_addr_list, list) {
if (entry->addr.id == id)
return entry;
}
return NULL;
}
int mptcp_userspace_pm_get_local_id(struct mptcp_sock *msk,
struct mptcp_addr_info *skc)
{
struct mptcp_pm_addr_entry *entry = NULL, *e, new_entry;
__be16 msk_sport = ((struct inet_sock *)
inet_sk((struct sock *)msk))->inet_sport;
spin_lock_bh(&msk->pm.lock);
list_for_each_entry(e, &msk->pm.userspace_pm_local_addr_list, list) {
if (mptcp_addresses_equal(&e->addr, skc, false)) {
entry = e;
break;
}
}
spin_unlock_bh(&msk->pm.lock);
if (entry)
return entry->addr.id;
memset(&new_entry, 0, sizeof(struct mptcp_pm_addr_entry));
new_entry.addr = *skc;
new_entry.addr.id = 0;
new_entry.flags = MPTCP_PM_ADDR_FLAG_IMPLICIT;
if (new_entry.addr.port == msk_sport)
new_entry.addr.port = 0;
return mptcp_userspace_pm_append_new_local_addr(msk, &new_entry, true);
}
bool mptcp_userspace_pm_is_backup(struct mptcp_sock *msk,
struct mptcp_addr_info *skc)
{
struct mptcp_pm_addr_entry *entry;
bool backup = false;
spin_lock_bh(&msk->pm.lock);
list_for_each_entry(entry, &msk->pm.userspace_pm_local_addr_list, list) {
if (mptcp_addresses_equal(&entry->addr, skc, false)) {
backup = !!(entry->flags & MPTCP_PM_ADDR_FLAG_BACKUP);
break;
}
}
spin_unlock_bh(&msk->pm.lock);
return backup;
}
int mptcp_pm_nl_announce_doit(struct sk_buff *skb, struct genl_info *info)
{
struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
struct nlattr *addr = info->attrs[MPTCP_PM_ATTR_ADDR];
struct mptcp_pm_addr_entry addr_val;
struct mptcp_sock *msk;
int err = -EINVAL;
struct sock *sk;
u32 token_val;
if (!addr || !token) {
GENL_SET_ERR_MSG(info, "missing required inputs");
return err;
}
token_val = nla_get_u32(token);
msk = mptcp_token_get_sock(sock_net(skb->sk), token_val);
if (!msk) {
NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token");
return err;
}
sk = (struct sock *)msk;
if (!mptcp_pm_is_userspace(msk)) {
GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected");
goto announce_err;
}
err = mptcp_pm_parse_entry(addr, info, true, &addr_val);
if (err < 0) {
GENL_SET_ERR_MSG(info, "error parsing local address");
goto announce_err;
}
if (addr_val.addr.id == 0 || !(addr_val.flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) {
GENL_SET_ERR_MSG(info, "invalid addr id or flags");
err = -EINVAL;
goto announce_err;
}
err = mptcp_userspace_pm_append_new_local_addr(msk, &addr_val, false);
if (err < 0) {
GENL_SET_ERR_MSG(info, "did not match address and id");
goto announce_err;
}
lock_sock(sk);
spin_lock_bh(&msk->pm.lock);
if (mptcp_pm_alloc_anno_list(msk, &addr_val.addr)) {
msk->pm.add_addr_signaled++;
mptcp_pm_announce_addr(msk, &addr_val.addr, false);
mptcp_pm_nl_addr_send_ack(msk);
}
spin_unlock_bh(&msk->pm.lock);
release_sock(sk);
err = 0;
announce_err:
sock_put(sk);
return err;
}
static int mptcp_userspace_pm_remove_id_zero_address(struct mptcp_sock *msk,
struct genl_info *info)
{
struct mptcp_rm_list list = { .nr = 0 };
struct mptcp_subflow_context *subflow;
struct sock *sk = (struct sock *)msk;
bool has_id_0 = false;
int err = -EINVAL;
lock_sock(sk);
mptcp_for_each_subflow(msk, subflow) {
if (READ_ONCE(subflow->local_id) == 0) {
has_id_0 = true;
break;
}
}
if (!has_id_0) {
GENL_SET_ERR_MSG(info, "address with id 0 not found");
goto remove_err;
}
list.ids[list.nr++] = 0;
spin_lock_bh(&msk->pm.lock);
mptcp_pm_remove_addr(msk, &list);
spin_unlock_bh(&msk->pm.lock);
err = 0;
remove_err:
release_sock(sk);
return err;
}
int mptcp_pm_nl_remove_doit(struct sk_buff *skb, struct genl_info *info)
{
struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
struct nlattr *id = info->attrs[MPTCP_PM_ATTR_LOC_ID];
struct mptcp_pm_addr_entry *match;
struct mptcp_pm_addr_entry *entry;
struct mptcp_sock *msk;
LIST_HEAD(free_list);
int err = -EINVAL;
struct sock *sk;
u32 token_val;
u8 id_val;
if (!id || !token) {
GENL_SET_ERR_MSG(info, "missing required inputs");
return err;
}
id_val = nla_get_u8(id);
token_val = nla_get_u32(token);
msk = mptcp_token_get_sock(sock_net(skb->sk), token_val);
if (!msk) {
NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token");
return err;
}
sk = (struct sock *)msk;
if (!mptcp_pm_is_userspace(msk)) {
GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected");
goto out;
}
if (id_val == 0) {
err = mptcp_userspace_pm_remove_id_zero_address(msk, info);
goto out;
}
lock_sock(sk);
match = mptcp_userspace_pm_lookup_addr_by_id(msk, id_val);
if (!match) {
GENL_SET_ERR_MSG(info, "address with specified id not found");
release_sock(sk);
goto out;
}
list_move(&match->list, &free_list);
mptcp_pm_remove_addrs(msk, &free_list);
release_sock(sk);
list_for_each_entry_safe(match, entry, &free_list, list) {
sock_kfree_s(sk, match, sizeof(*match));
}
err = 0;
out:
sock_put(sk);
return err;
}
int mptcp_pm_nl_subflow_create_doit(struct sk_buff *skb, struct genl_info *info)
{
struct nlattr *raddr = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE];
struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
struct nlattr *laddr = info->attrs[MPTCP_PM_ATTR_ADDR];
struct mptcp_pm_addr_entry entry = { 0 };
struct mptcp_addr_info addr_r;
struct mptcp_pm_local local;
struct mptcp_sock *msk;
int err = -EINVAL;
struct sock *sk;
u32 token_val;
if (!laddr || !raddr || !token) {
GENL_SET_ERR_MSG(info, "missing required inputs");
return err;
}
token_val = nla_get_u32(token);
msk = mptcp_token_get_sock(genl_info_net(info), token_val);
if (!msk) {
NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token");
return err;
}
sk = (struct sock *)msk;
if (!mptcp_pm_is_userspace(msk)) {
GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected");
goto create_err;
}
err = mptcp_pm_parse_entry(laddr, info, true, &entry);
if (err < 0) {
NL_SET_ERR_MSG_ATTR(info->extack, laddr, "error parsing local addr");
goto create_err;
}
if (entry.flags & MPTCP_PM_ADDR_FLAG_SIGNAL) {
GENL_SET_ERR_MSG(info, "invalid addr flags");
err = -EINVAL;
goto create_err;
}
entry.flags |= MPTCP_PM_ADDR_FLAG_SUBFLOW;
err = mptcp_pm_parse_addr(raddr, info, &addr_r);
if (err < 0) {
NL_SET_ERR_MSG_ATTR(info->extack, raddr, "error parsing remote addr");
goto create_err;
}
if (!mptcp_pm_addr_families_match(sk, &entry.addr, &addr_r)) {
GENL_SET_ERR_MSG(info, "families mismatch");
err = -EINVAL;
goto create_err;
}
err = mptcp_userspace_pm_append_new_local_addr(msk, &entry, false);
if (err < 0) {
GENL_SET_ERR_MSG(info, "did not match address and id");
goto create_err;
}
local.addr = entry.addr;
local.flags = entry.flags;
local.ifindex = entry.ifindex;
lock_sock(sk);
err = __mptcp_subflow_connect(sk, &local, &addr_r);
release_sock(sk);
spin_lock_bh(&msk->pm.lock);
if (err)
mptcp_userspace_pm_delete_local_addr(msk, &entry);
else
msk->pm.subflows++;
spin_unlock_bh(&msk->pm.lock);
create_err:
sock_put(sk);
return err;
}
static struct sock *mptcp_nl_find_ssk(struct mptcp_sock *msk,
const struct mptcp_addr_info *local,
const struct mptcp_addr_info *remote)
{
struct mptcp_subflow_context *subflow;
if (local->family != remote->family)
return NULL;
mptcp_for_each_subflow(msk, subflow) {
const struct inet_sock *issk;
struct sock *ssk;
ssk = mptcp_subflow_tcp_sock(subflow);
if (local->family != ssk->sk_family)
continue;
issk = inet_sk(ssk);
switch (ssk->sk_family) {
case AF_INET:
if (issk->inet_saddr != local->addr.s_addr ||
issk->inet_daddr != remote->addr.s_addr)
continue;
break;
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
case AF_INET6: {
const struct ipv6_pinfo *pinfo = inet6_sk(ssk);
if (!ipv6_addr_equal(&local->addr6, &pinfo->saddr) ||
!ipv6_addr_equal(&remote->addr6, &ssk->sk_v6_daddr))
continue;
break;
}
#endif
default:
continue;
}
if (issk->inet_sport == local->port &&
issk->inet_dport == remote->port)
return ssk;
}
return NULL;
}
int mptcp_pm_nl_subflow_destroy_doit(struct sk_buff *skb, struct genl_info *info)
{
struct nlattr *raddr = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE];
struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
struct nlattr *laddr = info->attrs[MPTCP_PM_ATTR_ADDR];
struct mptcp_addr_info addr_l;
struct mptcp_addr_info addr_r;
struct mptcp_sock *msk;
struct sock *sk, *ssk;
int err = -EINVAL;
u32 token_val;
if (!laddr || !raddr || !token) {
GENL_SET_ERR_MSG(info, "missing required inputs");
return err;
}
token_val = nla_get_u32(token);
msk = mptcp_token_get_sock(genl_info_net(info), token_val);
if (!msk) {
NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token");
return err;
}
sk = (struct sock *)msk;
if (!mptcp_pm_is_userspace(msk)) {
GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected");
goto destroy_err;
}
err = mptcp_pm_parse_addr(laddr, info, &addr_l);
if (err < 0) {
NL_SET_ERR_MSG_ATTR(info->extack, laddr, "error parsing local addr");
goto destroy_err;
}
err = mptcp_pm_parse_addr(raddr, info, &addr_r);
if (err < 0) {
NL_SET_ERR_MSG_ATTR(info->extack, raddr, "error parsing remote addr");
goto destroy_err;
}
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
if (addr_l.family == AF_INET && ipv6_addr_v4mapped(&addr_r.addr6)) {
ipv6_addr_set_v4mapped(addr_l.addr.s_addr, &addr_l.addr6);
addr_l.family = AF_INET6;
}
if (addr_r.family == AF_INET && ipv6_addr_v4mapped(&addr_l.addr6)) {
ipv6_addr_set_v4mapped(addr_r.addr.s_addr, &addr_r.addr6);
addr_r.family = AF_INET6;
}
#endif
if (addr_l.family != addr_r.family) {
GENL_SET_ERR_MSG(info, "address families do not match");
err = -EINVAL;
goto destroy_err;
}
if (!addr_l.port || !addr_r.port) {
GENL_SET_ERR_MSG(info, "missing local or remote port");
err = -EINVAL;
goto destroy_err;
}
lock_sock(sk);
ssk = mptcp_nl_find_ssk(msk, &addr_l, &addr_r);
if (ssk) {
struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
struct mptcp_pm_addr_entry entry = { .addr = addr_l };
spin_lock_bh(&msk->pm.lock);
mptcp_userspace_pm_delete_local_addr(msk, &entry);
spin_unlock_bh(&msk->pm.lock);
mptcp_subflow_shutdown(sk, ssk, RCV_SHUTDOWN | SEND_SHUTDOWN);
mptcp_close_ssk(sk, ssk, subflow);
MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_RMSUBFLOW);
err = 0;
} else {
err = -ESRCH;
}
release_sock(sk);
destroy_err:
sock_put(sk);
return err;
}
int mptcp_userspace_pm_set_flags(struct sk_buff *skb, struct genl_info *info)
{
struct mptcp_pm_addr_entry loc = { .addr = { .family = AF_UNSPEC }, };
struct mptcp_pm_addr_entry rem = { .addr = { .family = AF_UNSPEC }, };
struct nlattr *attr_rem = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE];
struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR];
struct net *net = sock_net(skb->sk);
struct mptcp_sock *msk;
int ret = -EINVAL;
struct sock *sk;
u32 token_val;
u8 bkup = 0;
token_val = nla_get_u32(token);
msk = mptcp_token_get_sock(net, token_val);
if (!msk) {
NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token");
return ret;
}
sk = (struct sock *)msk;
if (!mptcp_pm_is_userspace(msk)) {
GENL_SET_ERR_MSG(info, "userspace PM not selected");
goto set_flags_err;
}
ret = mptcp_pm_parse_entry(attr, info, false, &loc);
if (ret < 0)
goto set_flags_err;
if (attr_rem) {
ret = mptcp_pm_parse_entry(attr_rem, info, false, &rem);
if (ret < 0)
goto set_flags_err;
}
if (loc.addr.family == AF_UNSPEC ||
rem.addr.family == AF_UNSPEC) {
GENL_SET_ERR_MSG(info, "invalid address families");
ret = -EINVAL;
goto set_flags_err;
}
if (loc.flags & MPTCP_PM_ADDR_FLAG_BACKUP)
bkup = 1;
lock_sock(sk);
ret = mptcp_pm_nl_mp_prio_send_ack(msk, &loc.addr, &rem.addr, bkup);
release_sock(sk);
set_flags_err:
sock_put(sk);
return ret;
}
int mptcp_userspace_pm_dump_addr(struct sk_buff *msg,
struct netlink_callback *cb)
{
struct id_bitmap {
DECLARE_BITMAP(map, MPTCP_PM_MAX_ADDR_ID + 1);
} *bitmap;
const struct genl_info *info = genl_info_dump(cb);
struct net *net = sock_net(msg->sk);
struct mptcp_pm_addr_entry *entry;
struct mptcp_sock *msk;
struct nlattr *token;
int ret = -EINVAL;
struct sock *sk;
void *hdr;
bitmap = (struct id_bitmap *)cb->ctx;
token = info->attrs[MPTCP_PM_ATTR_TOKEN];
msk = mptcp_token_get_sock(net, nla_get_u32(token));
if (!msk) {
NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token");
return ret;
}
sk = (struct sock *)msk;
if (!mptcp_pm_is_userspace(msk)) {
GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected");
goto out;
}
lock_sock(sk);
spin_lock_bh(&msk->pm.lock);
list_for_each_entry(entry, &msk->pm.userspace_pm_local_addr_list, list) {
if (test_bit(entry->addr.id, bitmap->map))
continue;
hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq, &mptcp_genl_family,
NLM_F_MULTI, MPTCP_PM_CMD_GET_ADDR);
if (!hdr)
break;
if (mptcp_nl_fill_addr(msg, entry) < 0) {
genlmsg_cancel(msg, hdr);
break;
}
__set_bit(entry->addr.id, bitmap->map);
genlmsg_end(msg, hdr);
}
spin_unlock_bh(&msk->pm.lock);
release_sock(sk);
ret = msg->len;
out:
sock_put(sk);
return ret;
}
int mptcp_userspace_pm_get_addr(struct sk_buff *skb,
struct genl_info *info)
{
struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR];
struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
struct mptcp_pm_addr_entry addr, *entry;
struct net *net = sock_net(skb->sk);
struct mptcp_sock *msk;
struct sk_buff *msg;
int ret = -EINVAL;
struct sock *sk;
void *reply;
msk = mptcp_token_get_sock(net, nla_get_u32(token));
if (!msk) {
NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token");
return ret;
}
sk = (struct sock *)msk;
if (!mptcp_pm_is_userspace(msk)) {
GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected");
goto out;
}
ret = mptcp_pm_parse_entry(attr, info, false, &addr);
if (ret < 0)
goto out;
msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
if (!msg) {
ret = -ENOMEM;
goto out;
}
reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0,
info->genlhdr->cmd);
if (!reply) {
GENL_SET_ERR_MSG(info, "not enough space in Netlink message");
ret = -EMSGSIZE;
goto fail;
}
lock_sock(sk);
spin_lock_bh(&msk->pm.lock);
entry = mptcp_userspace_pm_lookup_addr_by_id(msk, addr.addr.id);
if (!entry) {
GENL_SET_ERR_MSG(info, "address not found");
ret = -EINVAL;
goto unlock_fail;
}
ret = mptcp_nl_fill_addr(msg, entry);
if (ret)
goto unlock_fail;
genlmsg_end(msg, reply);
ret = genlmsg_reply(msg, info);
spin_unlock_bh(&msk->pm.lock);
release_sock(sk);
sock_put(sk);
return ret;
unlock_fail:
spin_unlock_bh(&msk->pm.lock);
release_sock(sk);
fail:
nlmsg_free(msg);
out:
sock_put(sk);
return ret;
}