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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /net/handshake/request.c
parentInitial commit. (diff)
downloadlinux-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.c344
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);