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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /net/handshake/request.c | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'net/handshake/request.c')
-rw-r--r-- | net/handshake/request.c | 344 |
1 files changed, 344 insertions, 0 deletions
diff --git a/net/handshake/request.c b/net/handshake/request.c new file mode 100644 index 0000000000..94d5cef3e0 --- /dev/null +++ b/net/handshake/request.c @@ -0,0 +1,344 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Handshake request lifetime events + * + * Author: Chuck Lever <chuck.lever@oracle.com> + * + * Copyright (c) 2023, Oracle and/or its affiliates. + */ + +#include <linux/types.h> +#include <linux/socket.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/skbuff.h> +#include <linux/inet.h> +#include <linux/fdtable.h> +#include <linux/rhashtable.h> + +#include <net/sock.h> +#include <net/genetlink.h> +#include <net/netns/generic.h> + +#include <kunit/visibility.h> + +#include <uapi/linux/handshake.h> +#include "handshake.h" + +#include <trace/events/handshake.h> + +/* + * We need both a handshake_req -> sock mapping, and a sock -> + * handshake_req mapping. Both are one-to-one. + * + * To avoid adding another pointer field to struct sock, net/handshake + * maintains a hash table, indexed by the memory address of @sock, to + * find the struct handshake_req outstanding for that socket. The + * reverse direction uses a simple pointer field in the handshake_req + * struct. + */ + +static struct rhashtable handshake_rhashtbl ____cacheline_aligned_in_smp; + +static const struct rhashtable_params handshake_rhash_params = { + .key_len = sizeof_field(struct handshake_req, hr_sk), + .key_offset = offsetof(struct handshake_req, hr_sk), + .head_offset = offsetof(struct handshake_req, hr_rhash), + .automatic_shrinking = true, +}; + +int handshake_req_hash_init(void) +{ + return rhashtable_init(&handshake_rhashtbl, &handshake_rhash_params); +} + +void handshake_req_hash_destroy(void) +{ + rhashtable_destroy(&handshake_rhashtbl); +} + +struct handshake_req *handshake_req_hash_lookup(struct sock *sk) +{ + return rhashtable_lookup_fast(&handshake_rhashtbl, &sk, + handshake_rhash_params); +} +EXPORT_SYMBOL_IF_KUNIT(handshake_req_hash_lookup); + +static bool handshake_req_hash_add(struct handshake_req *req) +{ + int ret; + + ret = rhashtable_lookup_insert_fast(&handshake_rhashtbl, + &req->hr_rhash, + handshake_rhash_params); + return ret == 0; +} + +static void handshake_req_destroy(struct handshake_req *req) +{ + if (req->hr_proto->hp_destroy) + req->hr_proto->hp_destroy(req); + rhashtable_remove_fast(&handshake_rhashtbl, &req->hr_rhash, + handshake_rhash_params); + kfree(req); +} + +static void handshake_sk_destruct(struct sock *sk) +{ + void (*sk_destruct)(struct sock *sk); + struct handshake_req *req; + + req = handshake_req_hash_lookup(sk); + if (!req) + return; + + trace_handshake_destruct(sock_net(sk), req, sk); + sk_destruct = req->hr_odestruct; + handshake_req_destroy(req); + if (sk_destruct) + sk_destruct(sk); +} + +/** + * handshake_req_alloc - Allocate a handshake request + * @proto: security protocol + * @flags: memory allocation flags + * + * Returns an initialized handshake_req or NULL. + */ +struct handshake_req *handshake_req_alloc(const struct handshake_proto *proto, + gfp_t flags) +{ + struct handshake_req *req; + + if (!proto) + return NULL; + if (proto->hp_handler_class <= HANDSHAKE_HANDLER_CLASS_NONE) + return NULL; + if (proto->hp_handler_class >= HANDSHAKE_HANDLER_CLASS_MAX) + return NULL; + if (!proto->hp_accept || !proto->hp_done) + return NULL; + + req = kzalloc(struct_size(req, hr_priv, proto->hp_privsize), flags); + if (!req) + return NULL; + + INIT_LIST_HEAD(&req->hr_list); + req->hr_proto = proto; + return req; +} +EXPORT_SYMBOL(handshake_req_alloc); + +/** + * handshake_req_private - Get per-handshake private data + * @req: handshake arguments + * + */ +void *handshake_req_private(struct handshake_req *req) +{ + return (void *)&req->hr_priv; +} +EXPORT_SYMBOL(handshake_req_private); + +static bool __add_pending_locked(struct handshake_net *hn, + struct handshake_req *req) +{ + if (WARN_ON_ONCE(!list_empty(&req->hr_list))) + return false; + hn->hn_pending++; + list_add_tail(&req->hr_list, &hn->hn_requests); + return true; +} + +static void __remove_pending_locked(struct handshake_net *hn, + struct handshake_req *req) +{ + hn->hn_pending--; + list_del_init(&req->hr_list); +} + +/* + * Returns %true if the request was found on @net's pending list, + * otherwise %false. + * + * If @req was on a pending list, it has not yet been accepted. + */ +static bool remove_pending(struct handshake_net *hn, struct handshake_req *req) +{ + bool ret = false; + + spin_lock(&hn->hn_lock); + if (!list_empty(&req->hr_list)) { + __remove_pending_locked(hn, req); + ret = true; + } + spin_unlock(&hn->hn_lock); + + return ret; +} + +struct handshake_req *handshake_req_next(struct handshake_net *hn, int class) +{ + struct handshake_req *req, *pos; + + req = NULL; + spin_lock(&hn->hn_lock); + list_for_each_entry(pos, &hn->hn_requests, hr_list) { + if (pos->hr_proto->hp_handler_class != class) + continue; + __remove_pending_locked(hn, pos); + req = pos; + break; + } + spin_unlock(&hn->hn_lock); + + return req; +} +EXPORT_SYMBOL_IF_KUNIT(handshake_req_next); + +/** + * handshake_req_submit - Submit a handshake request + * @sock: open socket on which to perform the handshake + * @req: handshake arguments + * @flags: memory allocation flags + * + * Return values: + * %0: Request queued + * %-EINVAL: Invalid argument + * %-EBUSY: A handshake is already under way for this socket + * %-ESRCH: No handshake agent is available + * %-EAGAIN: Too many pending handshake requests + * %-ENOMEM: Failed to allocate memory + * %-EMSGSIZE: Failed to construct notification message + * %-EOPNOTSUPP: Handshake module not initialized + * + * A zero return value from handshake_req_submit() means that + * exactly one subsequent completion callback is guaranteed. + * + * A negative return value from handshake_req_submit() means that + * no completion callback will be done and that @req has been + * destroyed. + */ +int handshake_req_submit(struct socket *sock, struct handshake_req *req, + gfp_t flags) +{ + struct handshake_net *hn; + struct net *net; + int ret; + + if (!sock || !req || !sock->file) { + kfree(req); + return -EINVAL; + } + + req->hr_sk = sock->sk; + if (!req->hr_sk) { + kfree(req); + return -EINVAL; + } + req->hr_odestruct = req->hr_sk->sk_destruct; + req->hr_sk->sk_destruct = handshake_sk_destruct; + + ret = -EOPNOTSUPP; + net = sock_net(req->hr_sk); + hn = handshake_pernet(net); + if (!hn) + goto out_err; + + ret = -EAGAIN; + if (READ_ONCE(hn->hn_pending) >= hn->hn_pending_max) + goto out_err; + + spin_lock(&hn->hn_lock); + ret = -EOPNOTSUPP; + if (test_bit(HANDSHAKE_F_NET_DRAINING, &hn->hn_flags)) + goto out_unlock; + ret = -EBUSY; + if (!handshake_req_hash_add(req)) + goto out_unlock; + if (!__add_pending_locked(hn, req)) + goto out_unlock; + spin_unlock(&hn->hn_lock); + + ret = handshake_genl_notify(net, req->hr_proto, flags); + if (ret) { + trace_handshake_notify_err(net, req, req->hr_sk, ret); + if (remove_pending(hn, req)) + goto out_err; + } + + /* Prevent socket release while a handshake request is pending */ + sock_hold(req->hr_sk); + + trace_handshake_submit(net, req, req->hr_sk); + return 0; + +out_unlock: + spin_unlock(&hn->hn_lock); +out_err: + trace_handshake_submit_err(net, req, req->hr_sk, ret); + handshake_req_destroy(req); + return ret; +} +EXPORT_SYMBOL(handshake_req_submit); + +void handshake_complete(struct handshake_req *req, unsigned int status, + struct genl_info *info) +{ + struct sock *sk = req->hr_sk; + struct net *net = sock_net(sk); + + if (!test_and_set_bit(HANDSHAKE_F_REQ_COMPLETED, &req->hr_flags)) { + trace_handshake_complete(net, req, sk, status); + req->hr_proto->hp_done(req, status, info); + + /* Handshake request is no longer pending */ + sock_put(sk); + } +} +EXPORT_SYMBOL_IF_KUNIT(handshake_complete); + +/** + * handshake_req_cancel - Cancel an in-progress handshake + * @sk: socket on which there is an ongoing handshake + * + * Request cancellation races with request completion. To determine + * who won, callers examine the return value from this function. + * + * Return values: + * %true - Uncompleted handshake request was canceled + * %false - Handshake request already completed or not found + */ +bool handshake_req_cancel(struct sock *sk) +{ + struct handshake_req *req; + struct handshake_net *hn; + struct net *net; + + net = sock_net(sk); + req = handshake_req_hash_lookup(sk); + if (!req) { + trace_handshake_cancel_none(net, req, sk); + return false; + } + + hn = handshake_pernet(net); + if (hn && remove_pending(hn, req)) { + /* Request hadn't been accepted */ + goto out_true; + } + if (test_and_set_bit(HANDSHAKE_F_REQ_COMPLETED, &req->hr_flags)) { + /* Request already completed */ + trace_handshake_cancel_busy(net, req, sk); + return false; + } + +out_true: + trace_handshake_cancel(net, req, sk); + + /* Handshake request is no longer pending */ + sock_put(sk); + return true; +} +EXPORT_SYMBOL(handshake_req_cancel); |