From 3b3009ea8abb713b022d94fba95ec270cf6e7eae Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Mon, 17 Apr 2023 10:32:26 -0400 Subject: net/handshake: Create a NETLINK service for handling handshake requests When a kernel consumer needs a transport layer security session, it first needs a handshake to negotiate and establish a session. This negotiation can be done in user space via one of the several existing library implementations, or it can be done in the kernel. No in-kernel handshake implementations yet exist. In their absence, we add a netlink service that can: a. Notify a user space daemon that a handshake is needed. b. Once notified, the daemon calls the kernel back via this netlink service to get the handshake parameters, including an open socket on which to establish the session. c. Once the handshake is complete, the daemon reports the session status and other information via a second netlink operation. This operation marks that it is safe for the kernel to use the open socket and the security session established there. The notification service uses a multicast group. Each handshake mechanism (eg, tlshd) adopts its own group number so that the handshake services are completely independent of one another. The kernel can then tell via netlink_has_listeners() whether a handshake service is active and prepared to handle a handshake request. A new netlink operation, ACCEPT, acts like accept(2) in that it instantiates a file descriptor in the user space daemon's fd table. If this operation is successful, the reply carries the fd number, which can be treated as an open and ready file descriptor. While user space is performing the handshake, the kernel keeps its muddy paws off the open socket. A second new netlink operation, DONE, indicates that the user space daemon is finished with the socket and it is safe for the kernel to use again. The operation also indicates whether a session was established successfully. Signed-off-by: Chuck Lever Signed-off-by: Jakub Kicinski --- net/handshake/Makefile | 11 ++ net/handshake/genl.c | 57 ++++++++ net/handshake/genl.h | 23 ++++ net/handshake/handshake.h | 82 +++++++++++ net/handshake/netlink.c | 312 ++++++++++++++++++++++++++++++++++++++++++ net/handshake/request.c | 339 ++++++++++++++++++++++++++++++++++++++++++++++ net/handshake/trace.c | 20 +++ 7 files changed, 844 insertions(+) create mode 100644 net/handshake/Makefile create mode 100644 net/handshake/genl.c create mode 100644 net/handshake/genl.h create mode 100644 net/handshake/handshake.h create mode 100644 net/handshake/netlink.c create mode 100644 net/handshake/request.c create mode 100644 net/handshake/trace.c (limited to 'net/handshake') diff --git a/net/handshake/Makefile b/net/handshake/Makefile new file mode 100644 index 000000000000..d38736de45da --- /dev/null +++ b/net/handshake/Makefile @@ -0,0 +1,11 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# Makefile for the Generic HANDSHAKE service +# +# Author: Chuck Lever +# +# Copyright (c) 2023, Oracle and/or its affiliates. +# + +obj-y += handshake.o +handshake-y := genl.o netlink.o request.o trace.o diff --git a/net/handshake/genl.c b/net/handshake/genl.c new file mode 100644 index 000000000000..652f37d19bd6 --- /dev/null +++ b/net/handshake/genl.c @@ -0,0 +1,57 @@ +// SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) +/* Do not edit directly, auto-generated from: */ +/* Documentation/netlink/specs/handshake.yaml */ +/* YNL-GEN kernel source */ + +#include +#include + +#include "genl.h" + +#include + +/* HANDSHAKE_CMD_ACCEPT - do */ +static const struct nla_policy handshake_accept_nl_policy[HANDSHAKE_A_ACCEPT_HANDLER_CLASS + 1] = { + [HANDSHAKE_A_ACCEPT_HANDLER_CLASS] = NLA_POLICY_MAX(NLA_U32, 1), +}; + +/* HANDSHAKE_CMD_DONE - do */ +static const struct nla_policy handshake_done_nl_policy[HANDSHAKE_A_DONE_REMOTE_AUTH + 1] = { + [HANDSHAKE_A_DONE_STATUS] = { .type = NLA_U32, }, + [HANDSHAKE_A_DONE_SOCKFD] = { .type = NLA_U32, }, + [HANDSHAKE_A_DONE_REMOTE_AUTH] = { .type = NLA_U32, }, +}; + +/* Ops table for handshake */ +static const struct genl_split_ops handshake_nl_ops[] = { + { + .cmd = HANDSHAKE_CMD_ACCEPT, + .doit = handshake_nl_accept_doit, + .policy = handshake_accept_nl_policy, + .maxattr = HANDSHAKE_A_ACCEPT_HANDLER_CLASS, + .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO, + }, + { + .cmd = HANDSHAKE_CMD_DONE, + .doit = handshake_nl_done_doit, + .policy = handshake_done_nl_policy, + .maxattr = HANDSHAKE_A_DONE_REMOTE_AUTH, + .flags = GENL_CMD_CAP_DO, + }, +}; + +static const struct genl_multicast_group handshake_nl_mcgrps[] = { + [HANDSHAKE_NLGRP_NONE] = { "none", }, +}; + +struct genl_family handshake_nl_family __ro_after_init = { + .name = HANDSHAKE_FAMILY_NAME, + .version = HANDSHAKE_FAMILY_VERSION, + .netnsok = true, + .parallel_ops = true, + .module = THIS_MODULE, + .split_ops = handshake_nl_ops, + .n_split_ops = ARRAY_SIZE(handshake_nl_ops), + .mcgrps = handshake_nl_mcgrps, + .n_mcgrps = ARRAY_SIZE(handshake_nl_mcgrps), +}; diff --git a/net/handshake/genl.h b/net/handshake/genl.h new file mode 100644 index 000000000000..a1eb7ccccc7f --- /dev/null +++ b/net/handshake/genl.h @@ -0,0 +1,23 @@ +/* SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) */ +/* Do not edit directly, auto-generated from: */ +/* Documentation/netlink/specs/handshake.yaml */ +/* YNL-GEN kernel header */ + +#ifndef _LINUX_HANDSHAKE_GEN_H +#define _LINUX_HANDSHAKE_GEN_H + +#include +#include + +#include + +int handshake_nl_accept_doit(struct sk_buff *skb, struct genl_info *info); +int handshake_nl_done_doit(struct sk_buff *skb, struct genl_info *info); + +enum { + HANDSHAKE_NLGRP_NONE, +}; + +extern struct genl_family handshake_nl_family; + +#endif /* _LINUX_HANDSHAKE_GEN_H */ diff --git a/net/handshake/handshake.h b/net/handshake/handshake.h new file mode 100644 index 000000000000..52568dbe24f1 --- /dev/null +++ b/net/handshake/handshake.h @@ -0,0 +1,82 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Generic netlink handshake service + * + * Author: Chuck Lever + * + * Copyright (c) 2023, Oracle and/or its affiliates. + */ + +#ifndef _INTERNAL_HANDSHAKE_H +#define _INTERNAL_HANDSHAKE_H + +/* Per-net namespace context */ +struct handshake_net { + spinlock_t hn_lock; /* protects next 3 fields */ + int hn_pending; + int hn_pending_max; + struct list_head hn_requests; + + unsigned long hn_flags; +}; + +enum hn_flags_bits { + HANDSHAKE_F_NET_DRAINING, +}; + +struct handshake_proto; + +/* One handshake request */ +struct handshake_req { + struct list_head hr_list; + struct rhash_head hr_rhash; + unsigned long hr_flags; + const struct handshake_proto *hr_proto; + struct sock *hr_sk; + void (*hr_odestruct)(struct sock *sk); + + /* Always the last field */ + char hr_priv[]; +}; + +enum hr_flags_bits { + HANDSHAKE_F_REQ_COMPLETED, +}; + +/* Invariants for all handshake requests for one transport layer + * security protocol + */ +struct handshake_proto { + int hp_handler_class; + size_t hp_privsize; + + int (*hp_accept)(struct handshake_req *req, + struct genl_info *info, int fd); + void (*hp_done)(struct handshake_req *req, + unsigned int status, + struct genl_info *info); + void (*hp_destroy)(struct handshake_req *req); +}; + +/* netlink.c */ +int handshake_genl_notify(struct net *net, const struct handshake_proto *proto, + gfp_t flags); +struct nlmsghdr *handshake_genl_put(struct sk_buff *msg, + struct genl_info *info); +struct handshake_net *handshake_pernet(struct net *net); + +/* request.c */ +struct handshake_req *handshake_req_alloc(const struct handshake_proto *proto, + gfp_t flags); +int handshake_req_hash_init(void); +void handshake_req_hash_destroy(void); +void *handshake_req_private(struct handshake_req *req); +struct handshake_req *handshake_req_hash_lookup(struct sock *sk); +struct handshake_req *handshake_req_next(struct handshake_net *hn, int class); +int handshake_req_submit(struct socket *sock, struct handshake_req *req, + gfp_t flags); +void handshake_complete(struct handshake_req *req, unsigned int status, + struct genl_info *info); +bool handshake_req_cancel(struct sock *sk); + +#endif /* _INTERNAL_HANDSHAKE_H */ diff --git a/net/handshake/netlink.c b/net/handshake/netlink.c new file mode 100644 index 000000000000..7264cac04047 --- /dev/null +++ b/net/handshake/netlink.c @@ -0,0 +1,312 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Generic netlink handshake service + * + * Author: Chuck Lever + * + * Copyright (c) 2023, Oracle and/or its affiliates. + */ + +#include +#include +#include +#include +#include +#include + +#include +#include +#include + +#include +#include "handshake.h" +#include "genl.h" + +#include + +/** + * handshake_genl_notify - Notify handlers that a request is waiting + * @net: target network namespace + * @proto: handshake protocol + * @flags: memory allocation control flags + * + * Returns zero on success or a negative errno if notification failed. + */ +int handshake_genl_notify(struct net *net, const struct handshake_proto *proto, + gfp_t flags) +{ + struct sk_buff *msg; + void *hdr; + + if (!genl_has_listeners(&handshake_nl_family, net, + proto->hp_handler_class)) + return -ESRCH; + + msg = genlmsg_new(GENLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) + return -ENOMEM; + + hdr = genlmsg_put(msg, 0, 0, &handshake_nl_family, 0, + HANDSHAKE_CMD_READY); + if (!hdr) + goto out_free; + + if (nla_put_u32(msg, HANDSHAKE_A_ACCEPT_HANDLER_CLASS, + proto->hp_handler_class) < 0) { + genlmsg_cancel(msg, hdr); + goto out_free; + } + + genlmsg_end(msg, hdr); + return genlmsg_multicast_netns(&handshake_nl_family, net, msg, + 0, proto->hp_handler_class, flags); + +out_free: + nlmsg_free(msg); + return -EMSGSIZE; +} + +/** + * handshake_genl_put - Create a generic netlink message header + * @msg: buffer in which to create the header + * @info: generic netlink message context + * + * Returns a ready-to-use header, or NULL. + */ +struct nlmsghdr *handshake_genl_put(struct sk_buff *msg, + struct genl_info *info) +{ + return genlmsg_put(msg, info->snd_portid, info->snd_seq, + &handshake_nl_family, 0, info->genlhdr->cmd); +} +EXPORT_SYMBOL(handshake_genl_put); + +/* + * dup() a kernel socket for use as a user space file descriptor + * in the current process. The kernel socket must have an + * instatiated struct file. + * + * Implicit argument: "current()" + */ +static int handshake_dup(struct socket *sock) +{ + struct file *file; + int newfd; + + if (!sock->file) + return -EBADF; + + file = get_file(sock->file); + newfd = get_unused_fd_flags(O_CLOEXEC); + if (newfd < 0) { + fput(file); + return newfd; + } + + fd_install(newfd, file); + return newfd; +} + +int handshake_nl_accept_doit(struct sk_buff *skb, struct genl_info *info) +{ + struct net *net = sock_net(skb->sk); + struct handshake_net *hn = handshake_pernet(net); + struct handshake_req *req = NULL; + struct socket *sock; + int class, fd, err; + + err = -EOPNOTSUPP; + if (!hn) + goto out_status; + + err = -EINVAL; + if (GENL_REQ_ATTR_CHECK(info, HANDSHAKE_A_ACCEPT_HANDLER_CLASS)) + goto out_status; + class = nla_get_u32(info->attrs[HANDSHAKE_A_ACCEPT_HANDLER_CLASS]); + + err = -EAGAIN; + req = handshake_req_next(hn, class); + if (!req) + goto out_status; + + sock = req->hr_sk->sk_socket; + fd = handshake_dup(sock); + if (fd < 0) { + err = fd; + goto out_complete; + } + err = req->hr_proto->hp_accept(req, info, fd); + if (err) + goto out_complete; + + trace_handshake_cmd_accept(net, req, req->hr_sk, fd); + return 0; + +out_complete: + handshake_complete(req, -EIO, NULL); + fput(sock->file); +out_status: + trace_handshake_cmd_accept_err(net, req, NULL, err); + return err; +} + +int handshake_nl_done_doit(struct sk_buff *skb, struct genl_info *info) +{ + struct net *net = sock_net(skb->sk); + struct socket *sock = NULL; + struct handshake_req *req; + int fd, status, err; + + if (GENL_REQ_ATTR_CHECK(info, HANDSHAKE_A_DONE_SOCKFD)) + return -EINVAL; + fd = nla_get_u32(info->attrs[HANDSHAKE_A_DONE_SOCKFD]); + + err = 0; + sock = sockfd_lookup(fd, &err); + if (err) { + err = -EBADF; + goto out_status; + } + + req = handshake_req_hash_lookup(sock->sk); + if (!req) { + err = -EBUSY; + fput(sock->file); + goto out_status; + } + + trace_handshake_cmd_done(net, req, sock->sk, fd); + + status = -EIO; + if (info->attrs[HANDSHAKE_A_DONE_STATUS]) + status = nla_get_u32(info->attrs[HANDSHAKE_A_DONE_STATUS]); + + handshake_complete(req, status, info); + fput(sock->file); + return 0; + +out_status: + trace_handshake_cmd_done_err(net, req, sock->sk, err); + return err; +} + +static unsigned int handshake_net_id; + +static int __net_init handshake_net_init(struct net *net) +{ + struct handshake_net *hn = net_generic(net, handshake_net_id); + unsigned long tmp; + struct sysinfo si; + + /* + * Arbitrary limit to prevent handshakes that do not make + * progress from clogging up the system. The cap scales up + * with the amount of physical memory on the system. + */ + si_meminfo(&si); + tmp = si.totalram / (25 * si.mem_unit); + hn->hn_pending_max = clamp(tmp, 3UL, 50UL); + + spin_lock_init(&hn->hn_lock); + hn->hn_pending = 0; + hn->hn_flags = 0; + INIT_LIST_HEAD(&hn->hn_requests); + return 0; +} + +static void __net_exit handshake_net_exit(struct net *net) +{ + struct handshake_net *hn = net_generic(net, handshake_net_id); + struct handshake_req *req; + LIST_HEAD(requests); + + /* + * Drain the net's pending list. Requests that have been + * accepted and are in progress will be destroyed when + * the socket is closed. + */ + spin_lock(&hn->hn_lock); + set_bit(HANDSHAKE_F_NET_DRAINING, &hn->hn_flags); + list_splice_init(&requests, &hn->hn_requests); + spin_unlock(&hn->hn_lock); + + while (!list_empty(&requests)) { + req = list_first_entry(&requests, struct handshake_req, hr_list); + list_del(&req->hr_list); + + /* + * Requests on this list have not yet been + * accepted, so they do not have an fd to put. + */ + + handshake_complete(req, -ETIMEDOUT, NULL); + } +} + +static struct pernet_operations __net_initdata handshake_genl_net_ops = { + .init = handshake_net_init, + .exit = handshake_net_exit, + .id = &handshake_net_id, + .size = sizeof(struct handshake_net), +}; + +/** + * handshake_pernet - Get the handshake private per-net structure + * @net: network namespace + * + * Returns a pointer to the net's private per-net structure for the + * handshake module, or NULL if handshake_init() failed. + */ +struct handshake_net *handshake_pernet(struct net *net) +{ + return handshake_net_id ? + net_generic(net, handshake_net_id) : NULL; +} + +static int __init handshake_init(void) +{ + int ret; + + ret = handshake_req_hash_init(); + if (ret) { + pr_warn("handshake: hash initialization failed (%d)\n", ret); + return ret; + } + + ret = genl_register_family(&handshake_nl_family); + if (ret) { + pr_warn("handshake: netlink registration failed (%d)\n", ret); + handshake_req_hash_destroy(); + return ret; + } + + /* + * ORDER: register_pernet_subsys must be done last. + * + * If initialization does not make it past pernet_subsys + * registration, then handshake_net_id will remain 0. That + * shunts the handshake consumer API to return ENOTSUPP + * to prevent it from dereferencing something that hasn't + * been allocated. + */ + ret = register_pernet_subsys(&handshake_genl_net_ops); + if (ret) { + pr_warn("handshake: pernet registration failed (%d)\n", ret); + genl_unregister_family(&handshake_nl_family); + handshake_req_hash_destroy(); + } + + return ret; +} + +static void __exit handshake_exit(void) +{ + unregister_pernet_subsys(&handshake_genl_net_ops); + handshake_net_id = 0; + + handshake_req_hash_destroy(); + genl_unregister_family(&handshake_nl_family); +} + +module_init(handshake_init); +module_exit(handshake_exit); diff --git a/net/handshake/request.c b/net/handshake/request.c new file mode 100644 index 000000000000..d5b2bc6de057 --- /dev/null +++ b/net/handshake/request.c @@ -0,0 +1,339 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Handshake request lifetime events + * + * Author: Chuck Lever + * + * Copyright (c) 2023, Oracle and/or its affiliates. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include + +#include +#include "handshake.h" + +#include + +/* + * 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); +} + +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; +} + +/** + * 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); + } +} + +/** + * 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); diff --git a/net/handshake/trace.c b/net/handshake/trace.c new file mode 100644 index 000000000000..1c4d8e27e17a --- /dev/null +++ b/net/handshake/trace.c @@ -0,0 +1,20 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Trace points for transport security layer handshakes. + * + * Author: Chuck Lever + * + * Copyright (c) 2023, Oracle and/or its affiliates. + */ + +#include + +#include +#include +#include + +#include "handshake.h" + +#define CREATE_TRACE_POINTS + +#include -- cgit From 2fd5532044a89d2403b543520b4902e196f7d165 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Mon, 17 Apr 2023 10:32:33 -0400 Subject: net/handshake: Add a kernel API for requesting a TLSv1.3 handshake To enable kernel consumers of TLS to request a TLS handshake, add support to net/handshake/ to request a handshake upcall. This patch also acts as a template for adding handshake upcall support for other kernel transport layer security providers. Signed-off-by: Chuck Lever Signed-off-by: Jakub Kicinski --- net/handshake/Makefile | 2 +- net/handshake/genl.c | 3 +- net/handshake/genl.h | 1 + net/handshake/tlshd.c | 417 +++++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 421 insertions(+), 2 deletions(-) create mode 100644 net/handshake/tlshd.c (limited to 'net/handshake') diff --git a/net/handshake/Makefile b/net/handshake/Makefile index d38736de45da..a089f7e3df24 100644 --- a/net/handshake/Makefile +++ b/net/handshake/Makefile @@ -8,4 +8,4 @@ # obj-y += handshake.o -handshake-y := genl.o netlink.o request.o trace.o +handshake-y := genl.o netlink.o request.o tlshd.o trace.o diff --git a/net/handshake/genl.c b/net/handshake/genl.c index 652f37d19bd6..9f29efb1493e 100644 --- a/net/handshake/genl.c +++ b/net/handshake/genl.c @@ -12,7 +12,7 @@ /* HANDSHAKE_CMD_ACCEPT - do */ static const struct nla_policy handshake_accept_nl_policy[HANDSHAKE_A_ACCEPT_HANDLER_CLASS + 1] = { - [HANDSHAKE_A_ACCEPT_HANDLER_CLASS] = NLA_POLICY_MAX(NLA_U32, 1), + [HANDSHAKE_A_ACCEPT_HANDLER_CLASS] = NLA_POLICY_MAX(NLA_U32, 2), }; /* HANDSHAKE_CMD_DONE - do */ @@ -42,6 +42,7 @@ static const struct genl_split_ops handshake_nl_ops[] = { static const struct genl_multicast_group handshake_nl_mcgrps[] = { [HANDSHAKE_NLGRP_NONE] = { "none", }, + [HANDSHAKE_NLGRP_TLSHD] = { "tlshd", }, }; struct genl_family handshake_nl_family __ro_after_init = { diff --git a/net/handshake/genl.h b/net/handshake/genl.h index a1eb7ccccc7f..2c1f1aa6a02a 100644 --- a/net/handshake/genl.h +++ b/net/handshake/genl.h @@ -16,6 +16,7 @@ int handshake_nl_done_doit(struct sk_buff *skb, struct genl_info *info); enum { HANDSHAKE_NLGRP_NONE, + HANDSHAKE_NLGRP_TLSHD, }; extern struct genl_family handshake_nl_family; diff --git a/net/handshake/tlshd.c b/net/handshake/tlshd.c new file mode 100644 index 000000000000..1b8353296060 --- /dev/null +++ b/net/handshake/tlshd.c @@ -0,0 +1,417 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Establish a TLS session for a kernel socket consumer + * using the tlshd user space handler. + * + * Author: Chuck Lever + * + * Copyright (c) 2021-2023, Oracle and/or its affiliates. + */ + +#include +#include +#include +#include +#include +#include + +#include +#include +#include + +#include +#include +#include "handshake.h" + +struct tls_handshake_req { + void (*th_consumer_done)(void *data, int status, + key_serial_t peerid); + void *th_consumer_data; + + int th_type; + unsigned int th_timeout_ms; + int th_auth_mode; + key_serial_t th_keyring; + key_serial_t th_certificate; + key_serial_t th_privkey; + + unsigned int th_num_peerids; + key_serial_t th_peerid[5]; +}; + +static struct tls_handshake_req * +tls_handshake_req_init(struct handshake_req *req, + const struct tls_handshake_args *args) +{ + struct tls_handshake_req *treq = handshake_req_private(req); + + treq->th_timeout_ms = args->ta_timeout_ms; + treq->th_consumer_done = args->ta_done; + treq->th_consumer_data = args->ta_data; + treq->th_keyring = args->ta_keyring; + treq->th_num_peerids = 0; + treq->th_certificate = TLS_NO_CERT; + treq->th_privkey = TLS_NO_PRIVKEY; + return treq; +} + +static void tls_handshake_remote_peerids(struct tls_handshake_req *treq, + struct genl_info *info) +{ + struct nlattr *head = nlmsg_attrdata(info->nlhdr, GENL_HDRLEN); + int rem, len = nlmsg_attrlen(info->nlhdr, GENL_HDRLEN); + struct nlattr *nla; + unsigned int i; + + i = 0; + nla_for_each_attr(nla, head, len, rem) { + if (nla_type(nla) == HANDSHAKE_A_DONE_REMOTE_AUTH) + i++; + } + if (!i) + return; + treq->th_num_peerids = min_t(unsigned int, i, + ARRAY_SIZE(treq->th_peerid)); + + i = 0; + nla_for_each_attr(nla, head, len, rem) { + if (nla_type(nla) == HANDSHAKE_A_DONE_REMOTE_AUTH) + treq->th_peerid[i++] = nla_get_u32(nla); + if (i >= treq->th_num_peerids) + break; + } +} + +/** + * tls_handshake_done - callback to handle a CMD_DONE request + * @req: socket on which the handshake was performed + * @status: session status code + * @info: full results of session establishment + * + */ +static void tls_handshake_done(struct handshake_req *req, + unsigned int status, struct genl_info *info) +{ + struct tls_handshake_req *treq = handshake_req_private(req); + + treq->th_peerid[0] = TLS_NO_PEERID; + if (info) + tls_handshake_remote_peerids(treq, info); + + treq->th_consumer_done(treq->th_consumer_data, -status, + treq->th_peerid[0]); +} + +#if IS_ENABLED(CONFIG_KEYS) +static int tls_handshake_private_keyring(struct tls_handshake_req *treq) +{ + key_ref_t process_keyring_ref, keyring_ref; + int ret; + + if (treq->th_keyring == TLS_NO_KEYRING) + return 0; + + process_keyring_ref = lookup_user_key(KEY_SPEC_PROCESS_KEYRING, + KEY_LOOKUP_CREATE, + KEY_NEED_WRITE); + if (IS_ERR(process_keyring_ref)) { + ret = PTR_ERR(process_keyring_ref); + goto out; + } + + keyring_ref = lookup_user_key(treq->th_keyring, KEY_LOOKUP_CREATE, + KEY_NEED_LINK); + if (IS_ERR(keyring_ref)) { + ret = PTR_ERR(keyring_ref); + goto out_put_key; + } + + ret = key_link(key_ref_to_ptr(process_keyring_ref), + key_ref_to_ptr(keyring_ref)); + + key_ref_put(keyring_ref); +out_put_key: + key_ref_put(process_keyring_ref); +out: + return ret; +} +#else +static int tls_handshake_private_keyring(struct tls_handshake_req *treq) +{ + return 0; +} +#endif + +static int tls_handshake_put_peer_identity(struct sk_buff *msg, + struct tls_handshake_req *treq) +{ + unsigned int i; + + for (i = 0; i < treq->th_num_peerids; i++) + if (nla_put_u32(msg, HANDSHAKE_A_ACCEPT_PEER_IDENTITY, + treq->th_peerid[i]) < 0) + return -EMSGSIZE; + return 0; +} + +static int tls_handshake_put_certificate(struct sk_buff *msg, + struct tls_handshake_req *treq) +{ + struct nlattr *entry_attr; + + if (treq->th_certificate == TLS_NO_CERT && + treq->th_privkey == TLS_NO_PRIVKEY) + return 0; + + entry_attr = nla_nest_start(msg, HANDSHAKE_A_ACCEPT_CERTIFICATE); + if (!entry_attr) + return -EMSGSIZE; + + if (nla_put_u32(msg, HANDSHAKE_A_X509_CERT, + treq->th_certificate) || + nla_put_u32(msg, HANDSHAKE_A_X509_PRIVKEY, + treq->th_privkey)) { + nla_nest_cancel(msg, entry_attr); + return -EMSGSIZE; + } + + nla_nest_end(msg, entry_attr); + return 0; +} + +/** + * tls_handshake_accept - callback to construct a CMD_ACCEPT response + * @req: handshake parameters to return + * @info: generic netlink message context + * @fd: file descriptor to be returned + * + * Returns zero on success, or a negative errno on failure. + */ +static int tls_handshake_accept(struct handshake_req *req, + struct genl_info *info, int fd) +{ + struct tls_handshake_req *treq = handshake_req_private(req); + struct nlmsghdr *hdr; + struct sk_buff *msg; + int ret; + + ret = tls_handshake_private_keyring(treq); + if (ret < 0) + goto out; + + ret = -ENOMEM; + msg = genlmsg_new(GENLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) + goto out; + hdr = handshake_genl_put(msg, info); + if (!hdr) + goto out_cancel; + + ret = -EMSGSIZE; + ret = nla_put_u32(msg, HANDSHAKE_A_ACCEPT_SOCKFD, fd); + if (ret < 0) + goto out_cancel; + ret = nla_put_u32(msg, HANDSHAKE_A_ACCEPT_MESSAGE_TYPE, treq->th_type); + if (ret < 0) + goto out_cancel; + if (treq->th_timeout_ms) { + ret = nla_put_u32(msg, HANDSHAKE_A_ACCEPT_TIMEOUT, treq->th_timeout_ms); + if (ret < 0) + goto out_cancel; + } + + ret = nla_put_u32(msg, HANDSHAKE_A_ACCEPT_AUTH_MODE, + treq->th_auth_mode); + if (ret < 0) + goto out_cancel; + switch (treq->th_auth_mode) { + case HANDSHAKE_AUTH_PSK: + ret = tls_handshake_put_peer_identity(msg, treq); + if (ret < 0) + goto out_cancel; + break; + case HANDSHAKE_AUTH_X509: + ret = tls_handshake_put_certificate(msg, treq); + if (ret < 0) + goto out_cancel; + break; + } + + genlmsg_end(msg, hdr); + return genlmsg_reply(msg, info); + +out_cancel: + genlmsg_cancel(msg, hdr); +out: + return ret; +} + +static const struct handshake_proto tls_handshake_proto = { + .hp_handler_class = HANDSHAKE_HANDLER_CLASS_TLSHD, + .hp_privsize = sizeof(struct tls_handshake_req), + + .hp_accept = tls_handshake_accept, + .hp_done = tls_handshake_done, +}; + +/** + * tls_client_hello_anon - request an anonymous TLS handshake on a socket + * @args: socket and handshake parameters for this request + * @flags: memory allocation control flags + * + * Return values: + * %0: Handshake request enqueue; ->done will be called when complete + * %-ESRCH: No user agent is available + * %-ENOMEM: Memory allocation failed + */ +int tls_client_hello_anon(const struct tls_handshake_args *args, gfp_t flags) +{ + struct tls_handshake_req *treq; + struct handshake_req *req; + + req = handshake_req_alloc(&tls_handshake_proto, flags); + if (!req) + return -ENOMEM; + treq = tls_handshake_req_init(req, args); + treq->th_type = HANDSHAKE_MSG_TYPE_CLIENTHELLO; + treq->th_auth_mode = HANDSHAKE_AUTH_UNAUTH; + + return handshake_req_submit(args->ta_sock, req, flags); +} +EXPORT_SYMBOL(tls_client_hello_anon); + +/** + * tls_client_hello_x509 - request an x.509-based TLS handshake on a socket + * @args: socket and handshake parameters for this request + * @flags: memory allocation control flags + * + * Return values: + * %0: Handshake request enqueue; ->done will be called when complete + * %-ESRCH: No user agent is available + * %-ENOMEM: Memory allocation failed + */ +int tls_client_hello_x509(const struct tls_handshake_args *args, gfp_t flags) +{ + struct tls_handshake_req *treq; + struct handshake_req *req; + + req = handshake_req_alloc(&tls_handshake_proto, flags); + if (!req) + return -ENOMEM; + treq = tls_handshake_req_init(req, args); + treq->th_type = HANDSHAKE_MSG_TYPE_CLIENTHELLO; + treq->th_auth_mode = HANDSHAKE_AUTH_X509; + treq->th_certificate = args->ta_my_cert; + treq->th_privkey = args->ta_my_privkey; + + return handshake_req_submit(args->ta_sock, req, flags); +} +EXPORT_SYMBOL(tls_client_hello_x509); + +/** + * tls_client_hello_psk - request a PSK-based TLS handshake on a socket + * @args: socket and handshake parameters for this request + * @flags: memory allocation control flags + * + * Return values: + * %0: Handshake request enqueue; ->done will be called when complete + * %-EINVAL: Wrong number of local peer IDs + * %-ESRCH: No user agent is available + * %-ENOMEM: Memory allocation failed + */ +int tls_client_hello_psk(const struct tls_handshake_args *args, gfp_t flags) +{ + struct tls_handshake_req *treq; + struct handshake_req *req; + unsigned int i; + + if (!args->ta_num_peerids || + args->ta_num_peerids > ARRAY_SIZE(treq->th_peerid)) + return -EINVAL; + + req = handshake_req_alloc(&tls_handshake_proto, flags); + if (!req) + return -ENOMEM; + treq = tls_handshake_req_init(req, args); + treq->th_type = HANDSHAKE_MSG_TYPE_CLIENTHELLO; + treq->th_auth_mode = HANDSHAKE_AUTH_PSK; + treq->th_num_peerids = args->ta_num_peerids; + for (i = 0; i < args->ta_num_peerids; i++) + treq->th_peerid[i] = args->ta_my_peerids[i]; + + return handshake_req_submit(args->ta_sock, req, flags); +} +EXPORT_SYMBOL(tls_client_hello_psk); + +/** + * tls_server_hello_x509 - request a server TLS handshake on a socket + * @args: socket and handshake parameters for this request + * @flags: memory allocation control flags + * + * Return values: + * %0: Handshake request enqueue; ->done will be called when complete + * %-ESRCH: No user agent is available + * %-ENOMEM: Memory allocation failed + */ +int tls_server_hello_x509(const struct tls_handshake_args *args, gfp_t flags) +{ + struct tls_handshake_req *treq; + struct handshake_req *req; + + req = handshake_req_alloc(&tls_handshake_proto, flags); + if (!req) + return -ENOMEM; + treq = tls_handshake_req_init(req, args); + treq->th_type = HANDSHAKE_MSG_TYPE_SERVERHELLO; + treq->th_auth_mode = HANDSHAKE_AUTH_X509; + treq->th_certificate = args->ta_my_cert; + treq->th_privkey = args->ta_my_privkey; + + return handshake_req_submit(args->ta_sock, req, flags); +} +EXPORT_SYMBOL(tls_server_hello_x509); + +/** + * tls_server_hello_psk - request a server TLS handshake on a socket + * @args: socket and handshake parameters for this request + * @flags: memory allocation control flags + * + * Return values: + * %0: Handshake request enqueue; ->done will be called when complete + * %-ESRCH: No user agent is available + * %-ENOMEM: Memory allocation failed + */ +int tls_server_hello_psk(const struct tls_handshake_args *args, gfp_t flags) +{ + struct tls_handshake_req *treq; + struct handshake_req *req; + + req = handshake_req_alloc(&tls_handshake_proto, flags); + if (!req) + return -ENOMEM; + treq = tls_handshake_req_init(req, args); + treq->th_type = HANDSHAKE_MSG_TYPE_SERVERHELLO; + treq->th_auth_mode = HANDSHAKE_AUTH_PSK; + treq->th_num_peerids = 1; + treq->th_peerid[0] = args->ta_my_peerids[0]; + + return handshake_req_submit(args->ta_sock, req, flags); +} +EXPORT_SYMBOL(tls_server_hello_psk); + +/** + * tls_handshake_cancel - cancel a pending 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 tls_handshake_cancel(struct sock *sk) +{ + return handshake_req_cancel(sk); +} +EXPORT_SYMBOL(tls_handshake_cancel); -- cgit From 88232ec1ec5ecf4aa5de439cff3d5e2b7adcac93 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Mon, 17 Apr 2023 10:32:39 -0400 Subject: net/handshake: Add Kunit tests for the handshake consumer API These verify the API contracts and help exercise lifetime rules for consumer sockets and handshake_req structures. One way to run these tests: ./tools/testing/kunit/kunit.py run --kunitconfig ./net/handshake/.kunitconfig Signed-off-by: Chuck Lever Signed-off-by: Jakub Kicinski --- net/handshake/.kunitconfig | 11 + net/handshake/Makefile | 2 + net/handshake/handshake-test.c | 523 +++++++++++++++++++++++++++++++++++++++++ net/handshake/handshake.h | 5 + net/handshake/netlink.c | 7 + net/handshake/request.c | 5 + net/handshake/tlshd.c | 1 + 7 files changed, 554 insertions(+) create mode 100644 net/handshake/.kunitconfig create mode 100644 net/handshake/handshake-test.c (limited to 'net/handshake') diff --git a/net/handshake/.kunitconfig b/net/handshake/.kunitconfig new file mode 100644 index 000000000000..5c48cf4abca2 --- /dev/null +++ b/net/handshake/.kunitconfig @@ -0,0 +1,11 @@ +CONFIG_KUNIT=y +CONFIG_UBSAN=y +CONFIG_STACKTRACE=y +CONFIG_NET=y +CONFIG_NETWORK_FILESYSTEMS=y +CONFIG_INET=y +CONFIG_MULTIUSER=y +CONFIG_NFS_FS=y +CONFIG_SUNRPC=y +CONFIG_NET_HANDSHAKE=y +CONFIG_NET_HANDSHAKE_KUNIT_TEST=y diff --git a/net/handshake/Makefile b/net/handshake/Makefile index a089f7e3df24..247d73c6ff6e 100644 --- a/net/handshake/Makefile +++ b/net/handshake/Makefile @@ -9,3 +9,5 @@ obj-y += handshake.o handshake-y := genl.o netlink.o request.o tlshd.o trace.o + +obj-$(CONFIG_NET_HANDSHAKE_KUNIT_TEST) += handshake-test.o diff --git a/net/handshake/handshake-test.c b/net/handshake/handshake-test.c new file mode 100644 index 000000000000..e6adc5dec11a --- /dev/null +++ b/net/handshake/handshake-test.c @@ -0,0 +1,523 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2023 Oracle and/or its affiliates. + * + * KUnit test of the handshake upcall mechanism. + */ + +#include +#include + +#include + +#include +#include +#include + +#include +#include "handshake.h" + +MODULE_IMPORT_NS(EXPORTED_FOR_KUNIT_TESTING); + +static int test_accept_func(struct handshake_req *req, struct genl_info *info, + int fd) +{ + return 0; +} + +static void test_done_func(struct handshake_req *req, unsigned int status, + struct genl_info *info) +{ +} + +struct handshake_req_alloc_test_param { + const char *desc; + struct handshake_proto *proto; + gfp_t gfp; + bool expect_success; +}; + +static struct handshake_proto handshake_req_alloc_proto_2 = { + .hp_handler_class = HANDSHAKE_HANDLER_CLASS_NONE, +}; + +static struct handshake_proto handshake_req_alloc_proto_3 = { + .hp_handler_class = HANDSHAKE_HANDLER_CLASS_MAX, +}; + +static struct handshake_proto handshake_req_alloc_proto_4 = { + .hp_handler_class = HANDSHAKE_HANDLER_CLASS_TLSHD, +}; + +static struct handshake_proto handshake_req_alloc_proto_5 = { + .hp_handler_class = HANDSHAKE_HANDLER_CLASS_TLSHD, + .hp_accept = test_accept_func, +}; + +static struct handshake_proto handshake_req_alloc_proto_6 = { + .hp_handler_class = HANDSHAKE_HANDLER_CLASS_TLSHD, + .hp_privsize = UINT_MAX, + .hp_accept = test_accept_func, + .hp_done = test_done_func, +}; + +static struct handshake_proto handshake_req_alloc_proto_good = { + .hp_handler_class = HANDSHAKE_HANDLER_CLASS_TLSHD, + .hp_accept = test_accept_func, + .hp_done = test_done_func, +}; + +static const +struct handshake_req_alloc_test_param handshake_req_alloc_params[] = { + { + .desc = "handshake_req_alloc NULL proto", + .proto = NULL, + .gfp = GFP_KERNEL, + .expect_success = false, + }, + { + .desc = "handshake_req_alloc CLASS_NONE", + .proto = &handshake_req_alloc_proto_2, + .gfp = GFP_KERNEL, + .expect_success = false, + }, + { + .desc = "handshake_req_alloc CLASS_MAX", + .proto = &handshake_req_alloc_proto_3, + .gfp = GFP_KERNEL, + .expect_success = false, + }, + { + .desc = "handshake_req_alloc no callbacks", + .proto = &handshake_req_alloc_proto_4, + .gfp = GFP_KERNEL, + .expect_success = false, + }, + { + .desc = "handshake_req_alloc no done callback", + .proto = &handshake_req_alloc_proto_5, + .gfp = GFP_KERNEL, + .expect_success = false, + }, + { + .desc = "handshake_req_alloc excessive privsize", + .proto = &handshake_req_alloc_proto_6, + .gfp = GFP_KERNEL, + .expect_success = false, + }, + { + .desc = "handshake_req_alloc all good", + .proto = &handshake_req_alloc_proto_good, + .gfp = GFP_KERNEL, + .expect_success = true, + }, +}; + +static void +handshake_req_alloc_get_desc(const struct handshake_req_alloc_test_param *param, + char *desc) +{ + strscpy(desc, param->desc, KUNIT_PARAM_DESC_SIZE); +} + +/* Creates the function handshake_req_alloc_gen_params */ +KUNIT_ARRAY_PARAM(handshake_req_alloc, handshake_req_alloc_params, + handshake_req_alloc_get_desc); + +static void handshake_req_alloc_case(struct kunit *test) +{ + const struct handshake_req_alloc_test_param *param = test->param_value; + struct handshake_req *result; + + /* Arrange */ + + /* Act */ + result = handshake_req_alloc(param->proto, param->gfp); + + /* Assert */ + if (param->expect_success) + KUNIT_EXPECT_NOT_NULL(test, result); + else + KUNIT_EXPECT_NULL(test, result); + + kfree(result); +} + +static void handshake_req_submit_test1(struct kunit *test) +{ + struct socket *sock; + int err, result; + + /* Arrange */ + err = __sock_create(&init_net, PF_INET, SOCK_STREAM, IPPROTO_TCP, + &sock, 1); + KUNIT_ASSERT_EQ(test, err, 0); + + /* Act */ + result = handshake_req_submit(sock, NULL, GFP_KERNEL); + + /* Assert */ + KUNIT_EXPECT_EQ(test, result, -EINVAL); + + sock_release(sock); +} + +static void handshake_req_submit_test2(struct kunit *test) +{ + struct handshake_req *req; + int result; + + /* Arrange */ + req = handshake_req_alloc(&handshake_req_alloc_proto_good, GFP_KERNEL); + KUNIT_ASSERT_NOT_NULL(test, req); + + /* Act */ + result = handshake_req_submit(NULL, req, GFP_KERNEL); + + /* Assert */ + KUNIT_EXPECT_EQ(test, result, -EINVAL); + + /* handshake_req_submit() destroys @req on error */ +} + +static void handshake_req_submit_test3(struct kunit *test) +{ + struct handshake_req *req; + struct socket *sock; + int err, result; + + /* Arrange */ + req = handshake_req_alloc(&handshake_req_alloc_proto_good, GFP_KERNEL); + KUNIT_ASSERT_NOT_NULL(test, req); + + err = __sock_create(&init_net, PF_INET, SOCK_STREAM, IPPROTO_TCP, + &sock, 1); + KUNIT_ASSERT_EQ(test, err, 0); + sock->file = NULL; + + /* Act */ + result = handshake_req_submit(sock, req, GFP_KERNEL); + + /* Assert */ + KUNIT_EXPECT_EQ(test, result, -EINVAL); + + /* handshake_req_submit() destroys @req on error */ + sock_release(sock); +} + +static void handshake_req_submit_test4(struct kunit *test) +{ + struct handshake_req *req, *result; + struct socket *sock; + int err; + + /* Arrange */ + req = handshake_req_alloc(&handshake_req_alloc_proto_good, GFP_KERNEL); + KUNIT_ASSERT_NOT_NULL(test, req); + + err = __sock_create(&init_net, PF_INET, SOCK_STREAM, IPPROTO_TCP, + &sock, 1); + KUNIT_ASSERT_EQ(test, err, 0); + sock->file = sock_alloc_file(sock, O_NONBLOCK, NULL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sock->file); + KUNIT_ASSERT_NOT_NULL(test, sock->sk); + + err = handshake_req_submit(sock, req, GFP_KERNEL); + KUNIT_ASSERT_EQ(test, err, 0); + + /* Act */ + result = handshake_req_hash_lookup(sock->sk); + + /* Assert */ + KUNIT_EXPECT_NOT_NULL(test, result); + KUNIT_EXPECT_PTR_EQ(test, req, result); + + handshake_req_cancel(sock->sk); + sock_release(sock); +} + +static void handshake_req_submit_test5(struct kunit *test) +{ + struct handshake_req *req; + struct handshake_net *hn; + struct socket *sock; + struct net *net; + int saved, err; + + /* Arrange */ + req = handshake_req_alloc(&handshake_req_alloc_proto_good, GFP_KERNEL); + KUNIT_ASSERT_NOT_NULL(test, req); + + err = __sock_create(&init_net, PF_INET, SOCK_STREAM, IPPROTO_TCP, + &sock, 1); + KUNIT_ASSERT_EQ(test, err, 0); + sock->file = sock_alloc_file(sock, O_NONBLOCK, NULL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sock->file); + KUNIT_ASSERT_NOT_NULL(test, sock->sk); + + net = sock_net(sock->sk); + hn = handshake_pernet(net); + KUNIT_ASSERT_NOT_NULL(test, hn); + + saved = hn->hn_pending; + hn->hn_pending = hn->hn_pending_max + 1; + + /* Act */ + err = handshake_req_submit(sock, req, GFP_KERNEL); + + /* Assert */ + KUNIT_EXPECT_EQ(test, err, -EAGAIN); + + sock_release(sock); + hn->hn_pending = saved; +} + +static void handshake_req_submit_test6(struct kunit *test) +{ + struct handshake_req *req1, *req2; + struct socket *sock; + int err; + + /* Arrange */ + req1 = handshake_req_alloc(&handshake_req_alloc_proto_good, GFP_KERNEL); + KUNIT_ASSERT_NOT_NULL(test, req1); + req2 = handshake_req_alloc(&handshake_req_alloc_proto_good, GFP_KERNEL); + KUNIT_ASSERT_NOT_NULL(test, req2); + + err = __sock_create(&init_net, PF_INET, SOCK_STREAM, IPPROTO_TCP, + &sock, 1); + KUNIT_ASSERT_EQ(test, err, 0); + sock->file = sock_alloc_file(sock, O_NONBLOCK, NULL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sock->file); + KUNIT_ASSERT_NOT_NULL(test, sock->sk); + + /* Act */ + err = handshake_req_submit(sock, req1, GFP_KERNEL); + KUNIT_ASSERT_EQ(test, err, 0); + err = handshake_req_submit(sock, req2, GFP_KERNEL); + + /* Assert */ + KUNIT_EXPECT_EQ(test, err, -EBUSY); + + handshake_req_cancel(sock->sk); + sock_release(sock); +} + +static void handshake_req_cancel_test1(struct kunit *test) +{ + struct handshake_req *req; + struct socket *sock; + bool result; + int err; + + /* Arrange */ + req = handshake_req_alloc(&handshake_req_alloc_proto_good, GFP_KERNEL); + KUNIT_ASSERT_NOT_NULL(test, req); + + err = __sock_create(&init_net, PF_INET, SOCK_STREAM, IPPROTO_TCP, + &sock, 1); + KUNIT_ASSERT_EQ(test, err, 0); + + sock->file = sock_alloc_file(sock, O_NONBLOCK, NULL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sock->file); + + err = handshake_req_submit(sock, req, GFP_KERNEL); + KUNIT_ASSERT_EQ(test, err, 0); + + /* NB: handshake_req hasn't been accepted */ + + /* Act */ + result = handshake_req_cancel(sock->sk); + + /* Assert */ + KUNIT_EXPECT_TRUE(test, result); + + sock_release(sock); +} + +static void handshake_req_cancel_test2(struct kunit *test) +{ + struct handshake_req *req, *next; + struct handshake_net *hn; + struct socket *sock; + struct net *net; + bool result; + int err; + + /* Arrange */ + req = handshake_req_alloc(&handshake_req_alloc_proto_good, GFP_KERNEL); + KUNIT_ASSERT_NOT_NULL(test, req); + + err = __sock_create(&init_net, PF_INET, SOCK_STREAM, IPPROTO_TCP, + &sock, 1); + KUNIT_ASSERT_EQ(test, err, 0); + + sock->file = sock_alloc_file(sock, O_NONBLOCK, NULL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sock->file); + + err = handshake_req_submit(sock, req, GFP_KERNEL); + KUNIT_ASSERT_EQ(test, err, 0); + + net = sock_net(sock->sk); + hn = handshake_pernet(net); + KUNIT_ASSERT_NOT_NULL(test, hn); + + /* Pretend to accept this request */ + next = handshake_req_next(hn, HANDSHAKE_HANDLER_CLASS_TLSHD); + KUNIT_ASSERT_PTR_EQ(test, req, next); + + /* Act */ + result = handshake_req_cancel(sock->sk); + + /* Assert */ + KUNIT_EXPECT_TRUE(test, result); + + sock_release(sock); +} + +static void handshake_req_cancel_test3(struct kunit *test) +{ + struct handshake_req *req, *next; + struct handshake_net *hn; + struct socket *sock; + struct net *net; + bool result; + int err; + + /* Arrange */ + req = handshake_req_alloc(&handshake_req_alloc_proto_good, GFP_KERNEL); + KUNIT_ASSERT_NOT_NULL(test, req); + + err = __sock_create(&init_net, PF_INET, SOCK_STREAM, IPPROTO_TCP, + &sock, 1); + KUNIT_ASSERT_EQ(test, err, 0); + + sock->file = sock_alloc_file(sock, O_NONBLOCK, NULL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sock->file); + + err = handshake_req_submit(sock, req, GFP_KERNEL); + KUNIT_ASSERT_EQ(test, err, 0); + + net = sock_net(sock->sk); + hn = handshake_pernet(net); + KUNIT_ASSERT_NOT_NULL(test, hn); + + /* Pretend to accept this request */ + next = handshake_req_next(hn, HANDSHAKE_HANDLER_CLASS_TLSHD); + KUNIT_ASSERT_PTR_EQ(test, req, next); + + /* Pretend to complete this request */ + handshake_complete(next, -ETIMEDOUT, NULL); + + /* Act */ + result = handshake_req_cancel(sock->sk); + + /* Assert */ + KUNIT_EXPECT_FALSE(test, result); + + sock_release(sock); +} + +static struct handshake_req *handshake_req_destroy_test; + +static void test_destroy_func(struct handshake_req *req) +{ + handshake_req_destroy_test = req; +} + +static struct handshake_proto handshake_req_alloc_proto_destroy = { + .hp_handler_class = HANDSHAKE_HANDLER_CLASS_TLSHD, + .hp_accept = test_accept_func, + .hp_done = test_done_func, + .hp_destroy = test_destroy_func, +}; + +static void handshake_req_destroy_test1(struct kunit *test) +{ + struct handshake_req *req; + struct socket *sock; + int err; + + /* Arrange */ + handshake_req_destroy_test = NULL; + + req = handshake_req_alloc(&handshake_req_alloc_proto_destroy, GFP_KERNEL); + KUNIT_ASSERT_NOT_NULL(test, req); + + err = __sock_create(&init_net, PF_INET, SOCK_STREAM, IPPROTO_TCP, + &sock, 1); + KUNIT_ASSERT_EQ(test, err, 0); + + sock->file = sock_alloc_file(sock, O_NONBLOCK, NULL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sock->file); + + err = handshake_req_submit(sock, req, GFP_KERNEL); + KUNIT_ASSERT_EQ(test, err, 0); + + handshake_req_cancel(sock->sk); + + /* Act */ + sock_release(sock); + + /* Assert */ + KUNIT_EXPECT_PTR_EQ(test, handshake_req_destroy_test, req); +} + +static struct kunit_case handshake_api_test_cases[] = { + { + .name = "req_alloc API fuzzing", + .run_case = handshake_req_alloc_case, + .generate_params = handshake_req_alloc_gen_params, + }, + { + .name = "req_submit NULL req arg", + .run_case = handshake_req_submit_test1, + }, + { + .name = "req_submit NULL sock arg", + .run_case = handshake_req_submit_test2, + }, + { + .name = "req_submit NULL sock->file", + .run_case = handshake_req_submit_test3, + }, + { + .name = "req_lookup works", + .run_case = handshake_req_submit_test4, + }, + { + .name = "req_submit max pending", + .run_case = handshake_req_submit_test5, + }, + { + .name = "req_submit multiple", + .run_case = handshake_req_submit_test6, + }, + { + .name = "req_cancel before accept", + .run_case = handshake_req_cancel_test1, + }, + { + .name = "req_cancel after accept", + .run_case = handshake_req_cancel_test2, + }, + { + .name = "req_cancel after done", + .run_case = handshake_req_cancel_test3, + }, + { + .name = "req_destroy works", + .run_case = handshake_req_destroy_test1, + }, + {} +}; + +static struct kunit_suite handshake_api_suite = { + .name = "Handshake API tests", + .test_cases = handshake_api_test_cases, +}; + +kunit_test_suites(&handshake_api_suite); + +MODULE_DESCRIPTION("Test handshake upcall API functions"); +MODULE_LICENSE("GPL"); diff --git a/net/handshake/handshake.h b/net/handshake/handshake.h index 52568dbe24f1..4dac965c99df 100644 --- a/net/handshake/handshake.h +++ b/net/handshake/handshake.h @@ -49,6 +49,7 @@ enum hr_flags_bits { struct handshake_proto { int hp_handler_class; size_t hp_privsize; + unsigned long hp_flags; int (*hp_accept)(struct handshake_req *req, struct genl_info *info, int fd); @@ -58,6 +59,10 @@ struct handshake_proto { void (*hp_destroy)(struct handshake_req *req); }; +enum hp_flags_bits { + HANDSHAKE_F_PROTO_NOTIFY, +}; + /* netlink.c */ int handshake_genl_notify(struct net *net, const struct handshake_proto *proto, gfp_t flags); diff --git a/net/handshake/netlink.c b/net/handshake/netlink.c index 7264cac04047..8ea0ff993f9f 100644 --- a/net/handshake/netlink.c +++ b/net/handshake/netlink.c @@ -18,6 +18,8 @@ #include #include +#include + #include #include "handshake.h" #include "genl.h" @@ -38,6 +40,10 @@ int handshake_genl_notify(struct net *net, const struct handshake_proto *proto, struct sk_buff *msg; void *hdr; + /* Disable notifications during unit testing */ + if (!test_bit(HANDSHAKE_F_PROTO_NOTIFY, &proto->hp_flags)) + return 0; + if (!genl_has_listeners(&handshake_nl_family, net, proto->hp_handler_class)) return -ESRCH; @@ -262,6 +268,7 @@ struct handshake_net *handshake_pernet(struct net *net) return handshake_net_id ? net_generic(net, handshake_net_id) : NULL; } +EXPORT_SYMBOL_IF_KUNIT(handshake_pernet); static int __init handshake_init(void) { diff --git a/net/handshake/request.c b/net/handshake/request.c index d5b2bc6de057..94d5cef3e048 100644 --- a/net/handshake/request.c +++ b/net/handshake/request.c @@ -20,6 +20,8 @@ #include #include +#include + #include #include "handshake.h" @@ -60,6 +62,7 @@ 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) { @@ -192,6 +195,7 @@ struct handshake_req *handshake_req_next(struct handshake_net *hn, int class) return req; } +EXPORT_SYMBOL_IF_KUNIT(handshake_req_next); /** * handshake_req_submit - Submit a handshake request @@ -293,6 +297,7 @@ void handshake_complete(struct handshake_req *req, unsigned int status, sock_put(sk); } } +EXPORT_SYMBOL_IF_KUNIT(handshake_complete); /** * handshake_req_cancel - Cancel an in-progress handshake diff --git a/net/handshake/tlshd.c b/net/handshake/tlshd.c index 1b8353296060..fcbeb63b4eb1 100644 --- a/net/handshake/tlshd.c +++ b/net/handshake/tlshd.c @@ -249,6 +249,7 @@ out: static const struct handshake_proto tls_handshake_proto = { .hp_handler_class = HANDSHAKE_HANDLER_CLASS_TLSHD, .hp_privsize = sizeof(struct tls_handshake_req), + .hp_flags = BIT(HANDSHAKE_F_PROTO_NOTIFY), .hp_accept = tls_handshake_accept, .hp_done = tls_handshake_done, -- cgit From 6aa445e39693bff9c98b12f960e66b4e18c7378b Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Thu, 20 Apr 2023 19:37:23 +0200 Subject: net/handshake: Fix section mismatch in handshake_exit If CONFIG_NET_NS=n (e.g. m68k/defconfig): WARNING: modpost: vmlinux.o: section mismatch in reference: handshake_exit (section: .exit.text) -> handshake_genl_net_ops (section: .init.data) ERROR: modpost: Section mismatches detected. Fix this by dropping the __net_initdata tag from handshake_genl_net_ops. Fixes: 3b3009ea8abb713b ("net/handshake: Create a NETLINK service for handling handshake requests") Reported-by: noreply@ellerman.id.au Closes: http://kisskb.ellerman.id.au/kisskb/buildresult/14912987 Signed-off-by: Geert Uytterhoeven Reviewed-by: Chuck Lever Link: https://lore.kernel.org/r/20230420173723.3773434-1-geert@linux-m68k.org Signed-off-by: Jakub Kicinski --- net/handshake/netlink.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/handshake') diff --git a/net/handshake/netlink.c b/net/handshake/netlink.c index 8ea0ff993f9f..35c9c445e0b8 100644 --- a/net/handshake/netlink.c +++ b/net/handshake/netlink.c @@ -249,7 +249,7 @@ static void __net_exit handshake_net_exit(struct net *net) } } -static struct pernet_operations __net_initdata handshake_genl_net_ops = { +static struct pernet_operations handshake_genl_net_ops = { .init = handshake_net_init, .exit = handshake_net_exit, .id = &handshake_net_id, -- cgit From b21c7ba6d9a5532add3827a3b49f49cbc0cb9779 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Fri, 19 May 2023 13:12:50 -0400 Subject: net/handshake: Squelch allocation warning during Kunit test The "handshake_req_alloc excessive privsize" kunit test is intended to check what happens when the maximum privsize is exceeded. The WARN_ON_ONCE_GFP at mm/page_alloc.c:4744 can be disabled safely for this test. Reported-by: Linux Kernel Functional Testing Fixes: 88232ec1ec5e ("net/handshake: Add Kunit tests for the handshake consumer API") Signed-off-by: Chuck Lever Link: https://lore.kernel.org/r/168451636052.47152.9600443326570457947.stgit@oracle-102.nfsv4bat.org Signed-off-by: Jakub Kicinski --- net/handshake/handshake-test.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/handshake') diff --git a/net/handshake/handshake-test.c b/net/handshake/handshake-test.c index e6adc5dec11a..6193e46ee6d9 100644 --- a/net/handshake/handshake-test.c +++ b/net/handshake/handshake-test.c @@ -102,7 +102,7 @@ struct handshake_req_alloc_test_param handshake_req_alloc_params[] = { { .desc = "handshake_req_alloc excessive privsize", .proto = &handshake_req_alloc_proto_6, - .gfp = GFP_KERNEL, + .gfp = GFP_KERNEL | __GFP_NOWARN, .expect_success = false, }, { -- cgit From 18c40a1cc1d990c51381ef48cd93fdb31d5cd903 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Fri, 19 May 2023 13:08:24 -0400 Subject: net/handshake: Fix sock->file allocation sock->file = sock_alloc_file(sock, O_NONBLOCK, NULL); ^^^^ ^^^^ sock_alloc_file() calls release_sock() on error but the left hand side of the assignment dereferences "sock". This isn't the bug and I didn't report this earlier because there is an assert that it doesn't fail. net/handshake/handshake-test.c:221 handshake_req_submit_test4() error: dereferencing freed memory 'sock' net/handshake/handshake-test.c:233 handshake_req_submit_test4() warn: 'req' was already freed. net/handshake/handshake-test.c:254 handshake_req_submit_test5() error: dereferencing freed memory 'sock' net/handshake/handshake-test.c:290 handshake_req_submit_test6() error: dereferencing freed memory 'sock' net/handshake/handshake-test.c:321 handshake_req_cancel_test1() error: dereferencing freed memory 'sock' net/handshake/handshake-test.c:355 handshake_req_cancel_test2() error: dereferencing freed memory 'sock' net/handshake/handshake-test.c:367 handshake_req_cancel_test2() warn: 'req' was already freed. net/handshake/handshake-test.c:395 handshake_req_cancel_test3() error: dereferencing freed memory 'sock' net/handshake/handshake-test.c:407 handshake_req_cancel_test3() warn: 'req' was already freed. net/handshake/handshake-test.c:451 handshake_req_destroy_test1() error: dereferencing freed memory 'sock' net/handshake/handshake-test.c:463 handshake_req_destroy_test1() warn: 'req' was already freed. Reported-by: Dan Carpenter Fixes: 88232ec1ec5e ("net/handshake: Add Kunit tests for the handshake consumer API") Signed-off-by: Chuck Lever Link: https://lore.kernel.org/r/168451609436.45209.15407022385441542980.stgit@oracle-102.nfsv4bat.org Signed-off-by: Jakub Kicinski --- net/handshake/handshake-test.c | 42 ++++++++++++++++++++++++++++-------------- 1 file changed, 28 insertions(+), 14 deletions(-) (limited to 'net/handshake') diff --git a/net/handshake/handshake-test.c b/net/handshake/handshake-test.c index 6193e46ee6d9..6d37bab35c8f 100644 --- a/net/handshake/handshake-test.c +++ b/net/handshake/handshake-test.c @@ -209,6 +209,7 @@ static void handshake_req_submit_test4(struct kunit *test) { struct handshake_req *req, *result; struct socket *sock; + struct file *filp; int err; /* Arrange */ @@ -218,9 +219,10 @@ static void handshake_req_submit_test4(struct kunit *test) err = __sock_create(&init_net, PF_INET, SOCK_STREAM, IPPROTO_TCP, &sock, 1); KUNIT_ASSERT_EQ(test, err, 0); - sock->file = sock_alloc_file(sock, O_NONBLOCK, NULL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sock->file); + filp = sock_alloc_file(sock, O_NONBLOCK, NULL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, filp); KUNIT_ASSERT_NOT_NULL(test, sock->sk); + sock->file = filp; err = handshake_req_submit(sock, req, GFP_KERNEL); KUNIT_ASSERT_EQ(test, err, 0); @@ -241,6 +243,7 @@ static void handshake_req_submit_test5(struct kunit *test) struct handshake_req *req; struct handshake_net *hn; struct socket *sock; + struct file *filp; struct net *net; int saved, err; @@ -251,9 +254,10 @@ static void handshake_req_submit_test5(struct kunit *test) err = __sock_create(&init_net, PF_INET, SOCK_STREAM, IPPROTO_TCP, &sock, 1); KUNIT_ASSERT_EQ(test, err, 0); - sock->file = sock_alloc_file(sock, O_NONBLOCK, NULL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sock->file); + filp = sock_alloc_file(sock, O_NONBLOCK, NULL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, filp); KUNIT_ASSERT_NOT_NULL(test, sock->sk); + sock->file = filp; net = sock_net(sock->sk); hn = handshake_pernet(net); @@ -276,6 +280,7 @@ static void handshake_req_submit_test6(struct kunit *test) { struct handshake_req *req1, *req2; struct socket *sock; + struct file *filp; int err; /* Arrange */ @@ -287,9 +292,10 @@ static void handshake_req_submit_test6(struct kunit *test) err = __sock_create(&init_net, PF_INET, SOCK_STREAM, IPPROTO_TCP, &sock, 1); KUNIT_ASSERT_EQ(test, err, 0); - sock->file = sock_alloc_file(sock, O_NONBLOCK, NULL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sock->file); + filp = sock_alloc_file(sock, O_NONBLOCK, NULL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, filp); KUNIT_ASSERT_NOT_NULL(test, sock->sk); + sock->file = filp; /* Act */ err = handshake_req_submit(sock, req1, GFP_KERNEL); @@ -307,6 +313,7 @@ static void handshake_req_cancel_test1(struct kunit *test) { struct handshake_req *req; struct socket *sock; + struct file *filp; bool result; int err; @@ -318,8 +325,9 @@ static void handshake_req_cancel_test1(struct kunit *test) &sock, 1); KUNIT_ASSERT_EQ(test, err, 0); - sock->file = sock_alloc_file(sock, O_NONBLOCK, NULL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sock->file); + filp = sock_alloc_file(sock, O_NONBLOCK, NULL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, filp); + sock->file = filp; err = handshake_req_submit(sock, req, GFP_KERNEL); KUNIT_ASSERT_EQ(test, err, 0); @@ -340,6 +348,7 @@ static void handshake_req_cancel_test2(struct kunit *test) struct handshake_req *req, *next; struct handshake_net *hn; struct socket *sock; + struct file *filp; struct net *net; bool result; int err; @@ -352,8 +361,9 @@ static void handshake_req_cancel_test2(struct kunit *test) &sock, 1); KUNIT_ASSERT_EQ(test, err, 0); - sock->file = sock_alloc_file(sock, O_NONBLOCK, NULL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sock->file); + filp = sock_alloc_file(sock, O_NONBLOCK, NULL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, filp); + sock->file = filp; err = handshake_req_submit(sock, req, GFP_KERNEL); KUNIT_ASSERT_EQ(test, err, 0); @@ -380,6 +390,7 @@ static void handshake_req_cancel_test3(struct kunit *test) struct handshake_req *req, *next; struct handshake_net *hn; struct socket *sock; + struct file *filp; struct net *net; bool result; int err; @@ -392,8 +403,9 @@ static void handshake_req_cancel_test3(struct kunit *test) &sock, 1); KUNIT_ASSERT_EQ(test, err, 0); - sock->file = sock_alloc_file(sock, O_NONBLOCK, NULL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sock->file); + filp = sock_alloc_file(sock, O_NONBLOCK, NULL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, filp); + sock->file = filp; err = handshake_req_submit(sock, req, GFP_KERNEL); KUNIT_ASSERT_EQ(test, err, 0); @@ -436,6 +448,7 @@ static void handshake_req_destroy_test1(struct kunit *test) { struct handshake_req *req; struct socket *sock; + struct file *filp; int err; /* Arrange */ @@ -448,8 +461,9 @@ static void handshake_req_destroy_test1(struct kunit *test) &sock, 1); KUNIT_ASSERT_EQ(test, err, 0); - sock->file = sock_alloc_file(sock, O_NONBLOCK, NULL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sock->file); + filp = sock_alloc_file(sock, O_NONBLOCK, NULL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, filp); + sock->file = filp; err = handshake_req_submit(sock, req, GFP_KERNEL); KUNIT_ASSERT_EQ(test, err, 0); -- cgit From a095326e2c0f33743ce8e887d5b90edf3f36cced Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Thu, 11 May 2023 11:47:09 -0400 Subject: net/handshake: Remove unneeded check from handshake_dup() handshake_req_submit() now verifies that the socket has a file. Fixes: 3b3009ea8abb ("net/handshake: Create a NETLINK service for handling handshake requests") Reviewed-by: Simon Horman Signed-off-by: Chuck Lever Signed-off-by: Jakub Kicinski --- net/handshake/netlink.c | 3 --- 1 file changed, 3 deletions(-) (limited to 'net/handshake') diff --git a/net/handshake/netlink.c b/net/handshake/netlink.c index 35c9c445e0b8..7ec8a76c3c8a 100644 --- a/net/handshake/netlink.c +++ b/net/handshake/netlink.c @@ -99,9 +99,6 @@ static int handshake_dup(struct socket *sock) struct file *file; int newfd; - if (!sock->file) - return -EBADF; - file = get_file(sock->file); newfd = get_unused_fd_flags(O_CLOEXEC); if (newfd < 0) { -- cgit From 7ea9c1ec66bc099b0bfba961a8a46dfe25d7d8e4 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Thu, 11 May 2023 11:47:40 -0400 Subject: net/handshake: Fix handshake_dup() ref counting If get_unused_fd_flags() fails, we ended up calling fput(sock->file) twice. Reported-by: Dan Carpenter Suggested-by: Paolo Abeni Fixes: 3b3009ea8abb ("net/handshake: Create a NETLINK service for handling handshake requests") Signed-off-by: Chuck Lever Signed-off-by: Jakub Kicinski --- net/handshake/netlink.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'net/handshake') diff --git a/net/handshake/netlink.c b/net/handshake/netlink.c index 7ec8a76c3c8a..f5dc170689d9 100644 --- a/net/handshake/netlink.c +++ b/net/handshake/netlink.c @@ -139,15 +139,16 @@ int handshake_nl_accept_doit(struct sk_buff *skb, struct genl_info *info) goto out_complete; } err = req->hr_proto->hp_accept(req, info, fd); - if (err) + if (err) { + fput(sock->file); goto out_complete; + } trace_handshake_cmd_accept(net, req, req->hr_sk, fd); return 0; out_complete: handshake_complete(req, -EIO, NULL); - fput(sock->file); out_status: trace_handshake_cmd_accept_err(net, req, NULL, err); return err; -- cgit From 7afc6d0a107ffbd448c96eb2458b9e64a5af7860 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Thu, 11 May 2023 11:48:13 -0400 Subject: net/handshake: Fix uninitialized local variable trace_handshake_cmd_done_err() simply records the pointer in @req, so initializing it to NULL is sufficient and safe. Reported-by: Dan Carpenter Fixes: 3b3009ea8abb ("net/handshake: Create a NETLINK service for handling handshake requests") Reviewed-by: Simon Horman Signed-off-by: Chuck Lever Signed-off-by: Jakub Kicinski --- net/handshake/netlink.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/handshake') diff --git a/net/handshake/netlink.c b/net/handshake/netlink.c index f5dc170689d9..16a4bde648ba 100644 --- a/net/handshake/netlink.c +++ b/net/handshake/netlink.c @@ -157,8 +157,8 @@ out_status: int handshake_nl_done_doit(struct sk_buff *skb, struct genl_info *info) { struct net *net = sock_net(skb->sk); + struct handshake_req *req = NULL; struct socket *sock = NULL; - struct handshake_req *req; int fd, status, err; if (GENL_REQ_ATTR_CHECK(info, HANDSHAKE_A_DONE_SOCKFD)) -- cgit From fc490880e39d86c65ab2bcbd357af1950fa55e48 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Thu, 11 May 2023 11:48:45 -0400 Subject: net/handshake: handshake_genl_notify() shouldn't ignore @flags Reported-by: Dan Carpenter Fixes: 3b3009ea8abb ("net/handshake: Create a NETLINK service for handling handshake requests") Reviewed-by: Simon Horman Signed-off-by: Chuck Lever Signed-off-by: Jakub Kicinski --- net/handshake/netlink.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/handshake') diff --git a/net/handshake/netlink.c b/net/handshake/netlink.c index 16a4bde648ba..1086653e1fad 100644 --- a/net/handshake/netlink.c +++ b/net/handshake/netlink.c @@ -48,7 +48,7 @@ int handshake_genl_notify(struct net *net, const struct handshake_proto *proto, proto->hp_handler_class)) return -ESRCH; - msg = genlmsg_new(GENLMSG_DEFAULT_SIZE, GFP_KERNEL); + msg = genlmsg_new(GENLMSG_DEFAULT_SIZE, flags); if (!msg) return -ENOMEM; -- cgit From 1ce77c998f0415d7d9d91cb9bd7665e25c8f75f1 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Thu, 11 May 2023 11:49:17 -0400 Subject: net/handshake: Unpin sock->file if a handshake is cancelled If user space never calls DONE, sock->file's reference count remains elevated. Enable sock->file to be freed eventually in this case. Reported-by: Jakub Kacinski Fixes: 3b3009ea8abb ("net/handshake: Create a NETLINK service for handling handshake requests") Signed-off-by: Chuck Lever Signed-off-by: Jakub Kicinski --- net/handshake/handshake.h | 1 + net/handshake/request.c | 4 ++++ 2 files changed, 5 insertions(+) (limited to 'net/handshake') diff --git a/net/handshake/handshake.h b/net/handshake/handshake.h index 4dac965c99df..8aeaadca844f 100644 --- a/net/handshake/handshake.h +++ b/net/handshake/handshake.h @@ -31,6 +31,7 @@ struct handshake_req { struct list_head hr_list; struct rhash_head hr_rhash; unsigned long hr_flags; + struct file *hr_file; const struct handshake_proto *hr_proto; struct sock *hr_sk; void (*hr_odestruct)(struct sock *sk); diff --git a/net/handshake/request.c b/net/handshake/request.c index 94d5cef3e048..d78d41abb3d9 100644 --- a/net/handshake/request.c +++ b/net/handshake/request.c @@ -239,6 +239,7 @@ int handshake_req_submit(struct socket *sock, struct handshake_req *req, } req->hr_odestruct = req->hr_sk->sk_destruct; req->hr_sk->sk_destruct = handshake_sk_destruct; + req->hr_file = sock->file; ret = -EOPNOTSUPP; net = sock_net(req->hr_sk); @@ -334,6 +335,9 @@ bool handshake_req_cancel(struct sock *sk) return false; } + /* Request accepted and waiting for DONE */ + fput(req->hr_file); + out_true: trace_handshake_cancel(net, req, sk); -- cgit From 26fb5480a27d34975cc2b680b77af189620dd740 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Thu, 11 May 2023 11:49:50 -0400 Subject: net/handshake: Enable the SNI extension to work properly Enable the upper layer protocol to specify the SNI peername. This avoids the need for tlshd to use a DNS lookup, which can return a hostname that doesn't match the incoming certificate's SubjectName. Fixes: 2fd5532044a8 ("net/handshake: Add a kernel API for requesting a TLSv1.3 handshake") Reviewed-by: Simon Horman Signed-off-by: Chuck Lever Signed-off-by: Jakub Kicinski --- net/handshake/tlshd.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'net/handshake') diff --git a/net/handshake/tlshd.c b/net/handshake/tlshd.c index fcbeb63b4eb1..b735f5cced2f 100644 --- a/net/handshake/tlshd.c +++ b/net/handshake/tlshd.c @@ -31,6 +31,7 @@ struct tls_handshake_req { int th_type; unsigned int th_timeout_ms; int th_auth_mode; + const char *th_peername; key_serial_t th_keyring; key_serial_t th_certificate; key_serial_t th_privkey; @@ -48,6 +49,7 @@ tls_handshake_req_init(struct handshake_req *req, treq->th_timeout_ms = args->ta_timeout_ms; treq->th_consumer_done = args->ta_done; treq->th_consumer_data = args->ta_data; + treq->th_peername = args->ta_peername; treq->th_keyring = args->ta_keyring; treq->th_num_peerids = 0; treq->th_certificate = TLS_NO_CERT; @@ -214,6 +216,12 @@ static int tls_handshake_accept(struct handshake_req *req, ret = nla_put_u32(msg, HANDSHAKE_A_ACCEPT_MESSAGE_TYPE, treq->th_type); if (ret < 0) goto out_cancel; + if (treq->th_peername) { + ret = nla_put_string(msg, HANDSHAKE_A_ACCEPT_PEERNAME, + treq->th_peername); + if (ret < 0) + goto out_cancel; + } if (treq->th_timeout_ms) { ret = nla_put_u32(msg, HANDSHAKE_A_ACCEPT_TIMEOUT, treq->th_timeout_ms); if (ret < 0) -- cgit From 361b6889ae636926cdff517add240c3c8e24593a Mon Sep 17 00:00:00 2001 From: Lin Ma Date: Wed, 14 Jun 2023 09:52:49 +0800 Subject: net/handshake: remove fput() that causes use-after-free A reference underflow is found in TLS handshake subsystem that causes a direct use-after-free. Part of the crash log is like below: [ 2.022114] ------------[ cut here ]------------ [ 2.022193] refcount_t: underflow; use-after-free. [ 2.022288] WARNING: CPU: 0 PID: 60 at lib/refcount.c:28 refcount_warn_saturate+0xbe/0x110 [ 2.022432] Modules linked in: [ 2.022848] RIP: 0010:refcount_warn_saturate+0xbe/0x110 [ 2.023231] RSP: 0018:ffffc900001bfe18 EFLAGS: 00000286 [ 2.023325] RAX: 0000000000000000 RBX: 0000000000000007 RCX: 00000000ffffdfff [ 2.023438] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001 [ 2.023555] RBP: ffff888004c20098 R08: ffffffff82b392c8 R09: 00000000ffffdfff [ 2.023693] R10: ffffffff82a592e0 R11: ffffffff82b092e0 R12: ffff888004c200d8 [ 2.023813] R13: 0000000000000000 R14: ffff888004c20000 R15: ffffc90000013ca8 [ 2.023930] FS: 0000000000000000(0000) GS:ffff88807dc00000(0000) knlGS:0000000000000000 [ 2.024062] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 2.024161] CR2: ffff888003601000 CR3: 0000000002a2e000 CR4: 00000000000006f0 [ 2.024275] Call Trace: [ 2.024322] [ 2.024367] ? __warn+0x7f/0x130 [ 2.024430] ? refcount_warn_saturate+0xbe/0x110 [ 2.024513] ? report_bug+0x199/0x1b0 [ 2.024585] ? handle_bug+0x3c/0x70 [ 2.024676] ? exc_invalid_op+0x18/0x70 [ 2.024750] ? asm_exc_invalid_op+0x1a/0x20 [ 2.024830] ? refcount_warn_saturate+0xbe/0x110 [ 2.024916] ? refcount_warn_saturate+0xbe/0x110 [ 2.024998] __tcp_close+0x2f4/0x3d0 [ 2.025065] ? __pfx_kunit_generic_run_threadfn_adapter+0x10/0x10 [ 2.025168] tcp_close+0x1f/0x70 [ 2.025231] inet_release+0x33/0x60 [ 2.025297] sock_release+0x1f/0x80 [ 2.025361] handshake_req_cancel_test2+0x100/0x2d0 [ 2.025457] kunit_try_run_case+0x4c/0xa0 [ 2.025532] kunit_generic_run_threadfn_adapter+0x15/0x20 [ 2.025644] kthread+0xe1/0x110 [ 2.025708] ? __pfx_kthread+0x10/0x10 [ 2.025780] ret_from_fork+0x2c/0x50 One can enable CONFIG_NET_HANDSHAKE_KUNIT_TEST config to reproduce above crash. The root cause of this bug is that the commit 1ce77c998f04 ("net/handshake: Unpin sock->file if a handshake is cancelled") adds one additional fput() function. That patch claims that the fput() is used to enable sock->file to be freed even when user space never calls DONE. However, it seems that the intended DONE routine will never give an additional fput() of ths sock->file. The existing two of them are just used to balance the reference added in sockfd_lookup(). This patch revert the mentioned commit to avoid the use-after-free. The patched kernel could successfully pass the KUNIT test and boot to shell. [ 0.733613] # Subtest: Handshake API tests [ 0.734029] 1..11 [ 0.734255] KTAP version 1 [ 0.734542] # Subtest: req_alloc API fuzzing [ 0.736104] ok 1 handshake_req_alloc NULL proto [ 0.736114] ok 2 handshake_req_alloc CLASS_NONE [ 0.736559] ok 3 handshake_req_alloc CLASS_MAX [ 0.737020] ok 4 handshake_req_alloc no callbacks [ 0.737488] ok 5 handshake_req_alloc no done callback [ 0.737988] ok 6 handshake_req_alloc excessive privsize [ 0.738529] ok 7 handshake_req_alloc all good [ 0.739036] # req_alloc API fuzzing: pass:7 fail:0 skip:0 total:7 [ 0.739444] ok 1 req_alloc API fuzzing [ 0.740065] ok 2 req_submit NULL req arg [ 0.740436] ok 3 req_submit NULL sock arg [ 0.740834] ok 4 req_submit NULL sock->file [ 0.741236] ok 5 req_lookup works [ 0.741621] ok 6 req_submit max pending [ 0.741974] ok 7 req_submit multiple [ 0.742382] ok 8 req_cancel before accept [ 0.742764] ok 9 req_cancel after accept [ 0.743151] ok 10 req_cancel after done [ 0.743510] ok 11 req_destroy works [ 0.743882] # Handshake API tests: pass:11 fail:0 skip:0 total:11 [ 0.744205] # Totals: pass:17 fail:0 skip:0 total:17 Acked-by: Chuck Lever Fixes: 1ce77c998f04 ("net/handshake: Unpin sock->file if a handshake is cancelled") Signed-off-by: Lin Ma Link: https://lore.kernel.org/r/20230613083204.633896-1-linma@zju.edu.cn Link: https://lore.kernel.org/r/20230614015249.987448-1-linma@zju.edu.cn Signed-off-by: Jakub Kicinski --- net/handshake/handshake.h | 1 - net/handshake/request.c | 4 ---- 2 files changed, 5 deletions(-) (limited to 'net/handshake') diff --git a/net/handshake/handshake.h b/net/handshake/handshake.h index 8aeaadca844f..4dac965c99df 100644 --- a/net/handshake/handshake.h +++ b/net/handshake/handshake.h @@ -31,7 +31,6 @@ struct handshake_req { struct list_head hr_list; struct rhash_head hr_rhash; unsigned long hr_flags; - struct file *hr_file; const struct handshake_proto *hr_proto; struct sock *hr_sk; void (*hr_odestruct)(struct sock *sk); diff --git a/net/handshake/request.c b/net/handshake/request.c index d78d41abb3d9..94d5cef3e048 100644 --- a/net/handshake/request.c +++ b/net/handshake/request.c @@ -239,7 +239,6 @@ int handshake_req_submit(struct socket *sock, struct handshake_req *req, } req->hr_odestruct = req->hr_sk->sk_destruct; req->hr_sk->sk_destruct = handshake_sk_destruct; - req->hr_file = sock->file; ret = -EOPNOTSUPP; net = sock_net(req->hr_sk); @@ -335,9 +334,6 @@ bool handshake_req_cancel(struct sock *sk) return false; } - /* Request accepted and waiting for DONE */ - fput(req->hr_file); - out_true: trace_handshake_cancel(net, req, sk); -- cgit