diff options
Diffstat (limited to 'net/vmw_vsock/vmci_transport.c')
| -rw-r--r-- | net/vmw_vsock/vmci_transport.c | 2152 |
1 files changed, 2152 insertions, 0 deletions
diff --git a/net/vmw_vsock/vmci_transport.c b/net/vmw_vsock/vmci_transport.c new file mode 100644 index 000000000..8c2856cbf --- /dev/null +++ b/net/vmw_vsock/vmci_transport.c @@ -0,0 +1,2152 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * VMware vSockets Driver + * + * Copyright (C) 2007-2013 VMware, Inc. All rights reserved. + */ + +#include <linux/types.h> +#include <linux/bitops.h> +#include <linux/cred.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/kmod.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/net.h> +#include <linux/poll.h> +#include <linux/skbuff.h> +#include <linux/smp.h> +#include <linux/socket.h> +#include <linux/stddef.h> +#include <linux/unistd.h> +#include <linux/wait.h> +#include <linux/workqueue.h> +#include <net/sock.h> +#include <net/af_vsock.h> + +#include "vmci_transport_notify.h" + +static int vmci_transport_recv_dgram_cb(void *data, struct vmci_datagram *dg); +static int vmci_transport_recv_stream_cb(void *data, struct vmci_datagram *dg); +static void vmci_transport_peer_detach_cb(u32 sub_id, + const struct vmci_event_data *ed, + void *client_data); +static void vmci_transport_recv_pkt_work(struct work_struct *work); +static void vmci_transport_cleanup(struct work_struct *work); +static int vmci_transport_recv_listen(struct sock *sk, + struct vmci_transport_packet *pkt); +static int vmci_transport_recv_connecting_server( + struct sock *sk, + struct sock *pending, + struct vmci_transport_packet *pkt); +static int vmci_transport_recv_connecting_client( + struct sock *sk, + struct vmci_transport_packet *pkt); +static int vmci_transport_recv_connecting_client_negotiate( + struct sock *sk, + struct vmci_transport_packet *pkt); +static int vmci_transport_recv_connecting_client_invalid( + struct sock *sk, + struct vmci_transport_packet *pkt); +static int vmci_transport_recv_connected(struct sock *sk, + struct vmci_transport_packet *pkt); +static bool vmci_transport_old_proto_override(bool *old_pkt_proto); +static u16 vmci_transport_new_proto_supported_versions(void); +static bool vmci_transport_proto_to_notify_struct(struct sock *sk, u16 *proto, + bool old_pkt_proto); +static bool vmci_check_transport(struct vsock_sock *vsk); + +struct vmci_transport_recv_pkt_info { + struct work_struct work; + struct sock *sk; + struct vmci_transport_packet pkt; +}; + +static LIST_HEAD(vmci_transport_cleanup_list); +static DEFINE_SPINLOCK(vmci_transport_cleanup_lock); +static DECLARE_WORK(vmci_transport_cleanup_work, vmci_transport_cleanup); + +static struct vmci_handle vmci_transport_stream_handle = { VMCI_INVALID_ID, + VMCI_INVALID_ID }; +static u32 vmci_transport_qp_resumed_sub_id = VMCI_INVALID_ID; + +static int PROTOCOL_OVERRIDE = -1; + +static struct vsock_transport vmci_transport; /* forward declaration */ + +/* Helper function to convert from a VMCI error code to a VSock error code. */ + +static s32 vmci_transport_error_to_vsock_error(s32 vmci_error) +{ + switch (vmci_error) { + case VMCI_ERROR_NO_MEM: + return -ENOMEM; + case VMCI_ERROR_DUPLICATE_ENTRY: + case VMCI_ERROR_ALREADY_EXISTS: + return -EADDRINUSE; + case VMCI_ERROR_NO_ACCESS: + return -EPERM; + case VMCI_ERROR_NO_RESOURCES: + return -ENOBUFS; + case VMCI_ERROR_INVALID_RESOURCE: + return -EHOSTUNREACH; + case VMCI_ERROR_INVALID_ARGS: + default: + break; + } + return -EINVAL; +} + +static u32 vmci_transport_peer_rid(u32 peer_cid) +{ + if (VMADDR_CID_HYPERVISOR == peer_cid) + return VMCI_TRANSPORT_HYPERVISOR_PACKET_RID; + + return VMCI_TRANSPORT_PACKET_RID; +} + +static inline void +vmci_transport_packet_init(struct vmci_transport_packet *pkt, + struct sockaddr_vm *src, + struct sockaddr_vm *dst, + u8 type, + u64 size, + u64 mode, + struct vmci_transport_waiting_info *wait, + u16 proto, + struct vmci_handle handle) +{ + /* We register the stream control handler as an any cid handle so we + * must always send from a source address of VMADDR_CID_ANY + */ + pkt->dg.src = vmci_make_handle(VMADDR_CID_ANY, + VMCI_TRANSPORT_PACKET_RID); + pkt->dg.dst = vmci_make_handle(dst->svm_cid, + vmci_transport_peer_rid(dst->svm_cid)); + pkt->dg.payload_size = sizeof(*pkt) - sizeof(pkt->dg); + pkt->version = VMCI_TRANSPORT_PACKET_VERSION; + pkt->type = type; + pkt->src_port = src->svm_port; + pkt->dst_port = dst->svm_port; + memset(&pkt->proto, 0, sizeof(pkt->proto)); + memset(&pkt->_reserved2, 0, sizeof(pkt->_reserved2)); + + switch (pkt->type) { + case VMCI_TRANSPORT_PACKET_TYPE_INVALID: + pkt->u.size = 0; + break; + + case VMCI_TRANSPORT_PACKET_TYPE_REQUEST: + case VMCI_TRANSPORT_PACKET_TYPE_NEGOTIATE: + pkt->u.size = size; + break; + + case VMCI_TRANSPORT_PACKET_TYPE_OFFER: + case VMCI_TRANSPORT_PACKET_TYPE_ATTACH: + pkt->u.handle = handle; + break; + + case VMCI_TRANSPORT_PACKET_TYPE_WROTE: + case VMCI_TRANSPORT_PACKET_TYPE_READ: + case VMCI_TRANSPORT_PACKET_TYPE_RST: + pkt->u.size = 0; + break; + + case VMCI_TRANSPORT_PACKET_TYPE_SHUTDOWN: + pkt->u.mode = mode; + break; + + case VMCI_TRANSPORT_PACKET_TYPE_WAITING_READ: + case VMCI_TRANSPORT_PACKET_TYPE_WAITING_WRITE: + memcpy(&pkt->u.wait, wait, sizeof(pkt->u.wait)); + break; + + case VMCI_TRANSPORT_PACKET_TYPE_REQUEST2: + case VMCI_TRANSPORT_PACKET_TYPE_NEGOTIATE2: + pkt->u.size = size; + pkt->proto = proto; + break; + } +} + +static inline void +vmci_transport_packet_get_addresses(struct vmci_transport_packet *pkt, + struct sockaddr_vm *local, + struct sockaddr_vm *remote) +{ + vsock_addr_init(local, pkt->dg.dst.context, pkt->dst_port); + vsock_addr_init(remote, pkt->dg.src.context, pkt->src_port); +} + +static int +__vmci_transport_send_control_pkt(struct vmci_transport_packet *pkt, + struct sockaddr_vm *src, + struct sockaddr_vm *dst, + enum vmci_transport_packet_type type, + u64 size, + u64 mode, + struct vmci_transport_waiting_info *wait, + u16 proto, + struct vmci_handle handle, + bool convert_error) +{ + int err; + + vmci_transport_packet_init(pkt, src, dst, type, size, mode, wait, + proto, handle); + err = vmci_datagram_send(&pkt->dg); + if (convert_error && (err < 0)) + return vmci_transport_error_to_vsock_error(err); + + return err; +} + +static int +vmci_transport_reply_control_pkt_fast(struct vmci_transport_packet *pkt, + enum vmci_transport_packet_type type, + u64 size, + u64 mode, + struct vmci_transport_waiting_info *wait, + struct vmci_handle handle) +{ + struct vmci_transport_packet reply; + struct sockaddr_vm src, dst; + + if (pkt->type == VMCI_TRANSPORT_PACKET_TYPE_RST) { + return 0; + } else { + vmci_transport_packet_get_addresses(pkt, &src, &dst); + return __vmci_transport_send_control_pkt(&reply, &src, &dst, + type, + size, mode, wait, + VSOCK_PROTO_INVALID, + handle, true); + } +} + +static int +vmci_transport_send_control_pkt_bh(struct sockaddr_vm *src, + struct sockaddr_vm *dst, + enum vmci_transport_packet_type type, + u64 size, + u64 mode, + struct vmci_transport_waiting_info *wait, + struct vmci_handle handle) +{ + /* Note that it is safe to use a single packet across all CPUs since + * two tasklets of the same type are guaranteed to not ever run + * simultaneously. If that ever changes, or VMCI stops using tasklets, + * we can use per-cpu packets. + */ + static struct vmci_transport_packet pkt; + + return __vmci_transport_send_control_pkt(&pkt, src, dst, type, + size, mode, wait, + VSOCK_PROTO_INVALID, handle, + false); +} + +static int +vmci_transport_alloc_send_control_pkt(struct sockaddr_vm *src, + struct sockaddr_vm *dst, + enum vmci_transport_packet_type type, + u64 size, + u64 mode, + struct vmci_transport_waiting_info *wait, + u16 proto, + struct vmci_handle handle) +{ + struct vmci_transport_packet *pkt; + int err; + + pkt = kmalloc(sizeof(*pkt), GFP_KERNEL); + if (!pkt) + return -ENOMEM; + + err = __vmci_transport_send_control_pkt(pkt, src, dst, type, size, + mode, wait, proto, handle, + true); + kfree(pkt); + + return err; +} + +static int +vmci_transport_send_control_pkt(struct sock *sk, + enum vmci_transport_packet_type type, + u64 size, + u64 mode, + struct vmci_transport_waiting_info *wait, + u16 proto, + struct vmci_handle handle) +{ + struct vsock_sock *vsk; + + vsk = vsock_sk(sk); + + if (!vsock_addr_bound(&vsk->local_addr)) + return -EINVAL; + + if (!vsock_addr_bound(&vsk->remote_addr)) + return -EINVAL; + + return vmci_transport_alloc_send_control_pkt(&vsk->local_addr, + &vsk->remote_addr, + type, size, mode, + wait, proto, handle); +} + +static int vmci_transport_send_reset_bh(struct sockaddr_vm *dst, + struct sockaddr_vm *src, + struct vmci_transport_packet *pkt) +{ + if (pkt->type == VMCI_TRANSPORT_PACKET_TYPE_RST) + return 0; + return vmci_transport_send_control_pkt_bh( + dst, src, + VMCI_TRANSPORT_PACKET_TYPE_RST, 0, + 0, NULL, VMCI_INVALID_HANDLE); +} + +static int vmci_transport_send_reset(struct sock *sk, + struct vmci_transport_packet *pkt) +{ + struct sockaddr_vm *dst_ptr; + struct sockaddr_vm dst; + struct vsock_sock *vsk; + + if (pkt->type == VMCI_TRANSPORT_PACKET_TYPE_RST) + return 0; + + vsk = vsock_sk(sk); + + if (!vsock_addr_bound(&vsk->local_addr)) + return -EINVAL; + + if (vsock_addr_bound(&vsk->remote_addr)) { + dst_ptr = &vsk->remote_addr; + } else { + vsock_addr_init(&dst, pkt->dg.src.context, + pkt->src_port); + dst_ptr = &dst; + } + return vmci_transport_alloc_send_control_pkt(&vsk->local_addr, dst_ptr, + VMCI_TRANSPORT_PACKET_TYPE_RST, + 0, 0, NULL, VSOCK_PROTO_INVALID, + VMCI_INVALID_HANDLE); +} + +static int vmci_transport_send_negotiate(struct sock *sk, size_t size) +{ + return vmci_transport_send_control_pkt( + sk, + VMCI_TRANSPORT_PACKET_TYPE_NEGOTIATE, + size, 0, NULL, + VSOCK_PROTO_INVALID, + VMCI_INVALID_HANDLE); +} + +static int vmci_transport_send_negotiate2(struct sock *sk, size_t size, + u16 version) +{ + return vmci_transport_send_control_pkt( + sk, + VMCI_TRANSPORT_PACKET_TYPE_NEGOTIATE2, + size, 0, NULL, version, + VMCI_INVALID_HANDLE); +} + +static int vmci_transport_send_qp_offer(struct sock *sk, + struct vmci_handle handle) +{ + return vmci_transport_send_control_pkt( + sk, VMCI_TRANSPORT_PACKET_TYPE_OFFER, 0, + 0, NULL, + VSOCK_PROTO_INVALID, handle); +} + +static int vmci_transport_send_attach(struct sock *sk, + struct vmci_handle handle) +{ + return vmci_transport_send_control_pkt( + sk, VMCI_TRANSPORT_PACKET_TYPE_ATTACH, + 0, 0, NULL, VSOCK_PROTO_INVALID, + handle); +} + +static int vmci_transport_reply_reset(struct vmci_transport_packet *pkt) +{ + return vmci_transport_reply_control_pkt_fast( + pkt, + VMCI_TRANSPORT_PACKET_TYPE_RST, + 0, 0, NULL, + VMCI_INVALID_HANDLE); +} + +static int vmci_transport_send_invalid_bh(struct sockaddr_vm *dst, + struct sockaddr_vm *src) +{ + return vmci_transport_send_control_pkt_bh( + dst, src, + VMCI_TRANSPORT_PACKET_TYPE_INVALID, + 0, 0, NULL, VMCI_INVALID_HANDLE); +} + +int vmci_transport_send_wrote_bh(struct sockaddr_vm *dst, + struct sockaddr_vm *src) +{ + return vmci_transport_send_control_pkt_bh( + dst, src, + VMCI_TRANSPORT_PACKET_TYPE_WROTE, 0, + 0, NULL, VMCI_INVALID_HANDLE); +} + +int vmci_transport_send_read_bh(struct sockaddr_vm *dst, + struct sockaddr_vm *src) +{ + return vmci_transport_send_control_pkt_bh( + dst, src, + VMCI_TRANSPORT_PACKET_TYPE_READ, 0, + 0, NULL, VMCI_INVALID_HANDLE); +} + +int vmci_transport_send_wrote(struct sock *sk) +{ + return vmci_transport_send_control_pkt( + sk, VMCI_TRANSPORT_PACKET_TYPE_WROTE, 0, + 0, NULL, VSOCK_PROTO_INVALID, + VMCI_INVALID_HANDLE); +} + +int vmci_transport_send_read(struct sock *sk) +{ + return vmci_transport_send_control_pkt( + sk, VMCI_TRANSPORT_PACKET_TYPE_READ, 0, + 0, NULL, VSOCK_PROTO_INVALID, + VMCI_INVALID_HANDLE); +} + +int vmci_transport_send_waiting_write(struct sock *sk, + struct vmci_transport_waiting_info *wait) +{ + return vmci_transport_send_control_pkt( + sk, VMCI_TRANSPORT_PACKET_TYPE_WAITING_WRITE, + 0, 0, wait, VSOCK_PROTO_INVALID, + VMCI_INVALID_HANDLE); +} + +int vmci_transport_send_waiting_read(struct sock *sk, + struct vmci_transport_waiting_info *wait) +{ + return vmci_transport_send_control_pkt( + sk, VMCI_TRANSPORT_PACKET_TYPE_WAITING_READ, + 0, 0, wait, VSOCK_PROTO_INVALID, + VMCI_INVALID_HANDLE); +} + +static int vmci_transport_shutdown(struct vsock_sock *vsk, int mode) +{ + return vmci_transport_send_control_pkt( + &vsk->sk, + VMCI_TRANSPORT_PACKET_TYPE_SHUTDOWN, + 0, mode, NULL, + VSOCK_PROTO_INVALID, + VMCI_INVALID_HANDLE); +} + +static int vmci_transport_send_conn_request(struct sock *sk, size_t size) +{ + return vmci_transport_send_control_pkt(sk, + VMCI_TRANSPORT_PACKET_TYPE_REQUEST, + size, 0, NULL, + VSOCK_PROTO_INVALID, + VMCI_INVALID_HANDLE); +} + +static int vmci_transport_send_conn_request2(struct sock *sk, size_t size, + u16 version) +{ + return vmci_transport_send_control_pkt( + sk, VMCI_TRANSPORT_PACKET_TYPE_REQUEST2, + size, 0, NULL, version, + VMCI_INVALID_HANDLE); +} + +static struct sock *vmci_transport_get_pending( + struct sock *listener, + struct vmci_transport_packet *pkt) +{ + struct vsock_sock *vlistener; + struct vsock_sock *vpending; + struct sock *pending; + struct sockaddr_vm src; + + vsock_addr_init(&src, pkt->dg.src.context, pkt->src_port); + + vlistener = vsock_sk(listener); + + list_for_each_entry(vpending, &vlistener->pending_links, + pending_links) { + if (vsock_addr_equals_addr(&src, &vpending->remote_addr) && + pkt->dst_port == vpending->local_addr.svm_port) { + pending = sk_vsock(vpending); + sock_hold(pending); + goto found; + } + } + + pending = NULL; +found: + return pending; + +} + +static void vmci_transport_release_pending(struct sock *pending) +{ + sock_put(pending); +} + +/* We allow two kinds of sockets to communicate with a restricted VM: 1) + * trusted sockets 2) sockets from applications running as the same user as the + * VM (this is only true for the host side and only when using hosted products) + */ + +static bool vmci_transport_is_trusted(struct vsock_sock *vsock, u32 peer_cid) +{ + return vsock->trusted || + vmci_is_context_owner(peer_cid, vsock->owner->uid); +} + +/* We allow sending datagrams to and receiving datagrams from a restricted VM + * only if it is trusted as described in vmci_transport_is_trusted. + */ + +static bool vmci_transport_allow_dgram(struct vsock_sock *vsock, u32 peer_cid) +{ + if (VMADDR_CID_HYPERVISOR == peer_cid) + return true; + + if (vsock->cached_peer != peer_cid) { + vsock->cached_peer = peer_cid; + if (!vmci_transport_is_trusted(vsock, peer_cid) && + (vmci_context_get_priv_flags(peer_cid) & + VMCI_PRIVILEGE_FLAG_RESTRICTED)) { + vsock->cached_peer_allow_dgram = false; + } else { + vsock->cached_peer_allow_dgram = true; + } + } + + return vsock->cached_peer_allow_dgram; +} + +static int +vmci_transport_queue_pair_alloc(struct vmci_qp **qpair, + struct vmci_handle *handle, + u64 produce_size, + u64 consume_size, + u32 peer, u32 flags, bool trusted) +{ + int err = 0; + + if (trusted) { + /* Try to allocate our queue pair as trusted. This will only + * work if vsock is running in the host. + */ + + err = vmci_qpair_alloc(qpair, handle, produce_size, + consume_size, + peer, flags, + VMCI_PRIVILEGE_FLAG_TRUSTED); + if (err != VMCI_ERROR_NO_ACCESS) + goto out; + + } + + err = vmci_qpair_alloc(qpair, handle, produce_size, consume_size, + peer, flags, VMCI_NO_PRIVILEGE_FLAGS); +out: + if (err < 0) { + pr_err_once("Could not attach to queue pair with %d\n", err); + err = vmci_transport_error_to_vsock_error(err); + } + + return err; +} + +static int +vmci_transport_datagram_create_hnd(u32 resource_id, + u32 flags, + vmci_datagram_recv_cb recv_cb, + void *client_data, + struct vmci_handle *out_handle) +{ + int err = 0; + + /* Try to allocate our datagram handler as trusted. This will only work + * if vsock is running in the host. + */ + + err = vmci_datagram_create_handle_priv(resource_id, flags, + VMCI_PRIVILEGE_FLAG_TRUSTED, + recv_cb, + client_data, out_handle); + + if (err == VMCI_ERROR_NO_ACCESS) + err = vmci_datagram_create_handle(resource_id, flags, + recv_cb, client_data, + out_handle); + + return err; +} + +/* This is invoked as part of a tasklet that's scheduled when the VMCI + * interrupt fires. This is run in bottom-half context and if it ever needs to + * sleep it should defer that work to a work queue. + */ + +static int vmci_transport_recv_dgram_cb(void *data, struct vmci_datagram *dg) +{ + struct sock *sk; + size_t size; + struct sk_buff *skb; + struct vsock_sock *vsk; + + sk = (struct sock *)data; + + /* This handler is privileged when this module is running on the host. + * We will get datagrams from all endpoints (even VMs that are in a + * restricted context). If we get one from a restricted context then + * the destination socket must be trusted. + * + * NOTE: We access the socket struct without holding the lock here. + * This is ok because the field we are interested is never modified + * outside of the create and destruct socket functions. + */ + vsk = vsock_sk(sk); + if (!vmci_transport_allow_dgram(vsk, dg->src.context)) + return VMCI_ERROR_NO_ACCESS; + + size = VMCI_DG_SIZE(dg); + + /* Attach the packet to the socket's receive queue as an sk_buff. */ + skb = alloc_skb(size, GFP_ATOMIC); + if (!skb) + return VMCI_ERROR_NO_MEM; + + /* sk_receive_skb() will do a sock_put(), so hold here. */ + sock_hold(sk); + skb_put(skb, size); + memcpy(skb->data, dg, size); + sk_receive_skb(sk, skb, 0); + + return VMCI_SUCCESS; +} + +static bool vmci_transport_stream_allow(u32 cid, u32 port) +{ + static const u32 non_socket_contexts[] = { + VMADDR_CID_LOCAL, + }; + int i; + + BUILD_BUG_ON(sizeof(cid) != sizeof(*non_socket_contexts)); + + for (i = 0; i < ARRAY_SIZE(non_socket_contexts); i++) { + if (cid == non_socket_contexts[i]) + return false; + } + + return true; +} + +/* This is invoked as part of a tasklet that's scheduled when the VMCI + * interrupt fires. This is run in bottom-half context but it defers most of + * its work to the packet handling work queue. + */ + +static int vmci_transport_recv_stream_cb(void *data, struct vmci_datagram *dg) +{ + struct sock *sk; + struct sockaddr_vm dst; + struct sockaddr_vm src; + struct vmci_transport_packet *pkt; + struct vsock_sock *vsk; + bool bh_process_pkt; + int err; + + sk = NULL; + err = VMCI_SUCCESS; + bh_process_pkt = false; + + /* Ignore incoming packets from contexts without sockets, or resources + * that aren't vsock implementations. + */ + + if (!vmci_transport_stream_allow(dg->src.context, -1) + || vmci_transport_peer_rid(dg->src.context) != dg->src.resource) + return VMCI_ERROR_NO_ACCESS; + + if (VMCI_DG_SIZE(dg) < sizeof(*pkt)) + /* Drop datagrams that do not contain full VSock packets. */ + return VMCI_ERROR_INVALID_ARGS; + + pkt = (struct vmci_transport_packet *)dg; + + /* Find the socket that should handle this packet. First we look for a + * connected socket and if there is none we look for a socket bound to + * the destintation address. + */ + vsock_addr_init(&src, pkt->dg.src.context, pkt->src_port); + vsock_addr_init(&dst, pkt->dg.dst.context, pkt->dst_port); + + sk = vsock_find_connected_socket(&src, &dst); + if (!sk) { + sk = vsock_find_bound_socket(&dst); + if (!sk) { + /* We could not find a socket for this specified + * address. If this packet is a RST, we just drop it. + * If it is another packet, we send a RST. Note that + * we do not send a RST reply to RSTs so that we do not + * continually send RSTs between two endpoints. + * + * Note that since this is a reply, dst is src and src + * is dst. + */ + if (vmci_transport_send_reset_bh(&dst, &src, pkt) < 0) + pr_err("unable to send reset\n"); + + err = VMCI_ERROR_NOT_FOUND; + goto out; + } + } + + /* If the received packet type is beyond all types known to this + * implementation, reply with an invalid message. Hopefully this will + * help when implementing backwards compatibility in the future. + */ + if (pkt->type >= VMCI_TRANSPORT_PACKET_TYPE_MAX) { + vmci_transport_send_invalid_bh(&dst, &src); + err = VMCI_ERROR_INVALID_ARGS; + goto out; + } + + /* This handler is privileged when this module is running on the host. + * We will get datagram connect requests from all endpoints (even VMs + * that are in a restricted context). If we get one from a restricted + * context then the destination socket must be trusted. + * + * NOTE: We access the socket struct without holding the lock here. + * This is ok because the field we are interested is never modified + * outside of the create and destruct socket functions. + */ + vsk = vsock_sk(sk); + if (!vmci_transport_allow_dgram(vsk, pkt->dg.src.context)) { + err = VMCI_ERROR_NO_ACCESS; + goto out; + } + + /* We do most everything in a work queue, but let's fast path the + * notification of reads and writes to help data transfer performance. + * We can only do this if there is no process context code executing + * for this socket since that may change the state. + */ + bh_lock_sock(sk); + + if (!sock_owned_by_user(sk)) { + /* The local context ID may be out of date, update it. */ + vsk->local_addr.svm_cid = dst.svm_cid; + + if (sk->sk_state == TCP_ESTABLISHED) + vmci_trans(vsk)->notify_ops->handle_notify_pkt( + sk, pkt, true, &dst, &src, + &bh_process_pkt); + } + + bh_unlock_sock(sk); + + if (!bh_process_pkt) { + struct vmci_transport_recv_pkt_info *recv_pkt_info; + + recv_pkt_info = kmalloc(sizeof(*recv_pkt_info), GFP_ATOMIC); + if (!recv_pkt_info) { + if (vmci_transport_send_reset_bh(&dst, &src, pkt) < 0) + pr_err("unable to send reset\n"); + + err = VMCI_ERROR_NO_MEM; + goto out; + } + + recv_pkt_info->sk = sk; + memcpy(&recv_pkt_info->pkt, pkt, sizeof(recv_pkt_info->pkt)); + INIT_WORK(&recv_pkt_info->work, vmci_transport_recv_pkt_work); + + schedule_work(&recv_pkt_info->work); + /* Clear sk so that the reference count incremented by one of + * the Find functions above is not decremented below. We need + * that reference count for the packet handler we've scheduled + * to run. + */ + sk = NULL; + } + +out: + if (sk) + sock_put(sk); + + return err; +} + +static void vmci_transport_handle_detach(struct sock *sk) +{ + struct vsock_sock *vsk; + + vsk = vsock_sk(sk); + if (!vmci_handle_is_invalid(vmci_trans(vsk)->qp_handle)) { + sock_set_flag(sk, SOCK_DONE); + + /* On a detach the peer will not be sending or receiving + * anymore. + */ + vsk->peer_shutdown = SHUTDOWN_MASK; + + /* We should not be sending anymore since the peer won't be + * there to receive, but we can still receive if there is data + * left in our consume queue. If the local endpoint is a host, + * we can't call vsock_stream_has_data, since that may block, + * but a host endpoint can't read data once the VM has + * detached, so there is no available data in that case. + */ + if (vsk->local_addr.svm_cid == VMADDR_CID_HOST || + vsock_stream_has_data(vsk) <= 0) { + if (sk->sk_state == TCP_SYN_SENT) { + /* The peer may detach from a queue pair while + * we are still in the connecting state, i.e., + * if the peer VM is killed after attaching to + * a queue pair, but before we complete the + * handshake. In that case, we treat the detach + * event like a reset. + */ + + sk->sk_state = TCP_CLOSE; + sk->sk_err = ECONNRESET; + sk->sk_error_report(sk); + return; + } + sk->sk_state = TCP_CLOSE; + } + sk->sk_state_change(sk); + } +} + +static void vmci_transport_peer_detach_cb(u32 sub_id, + const struct vmci_event_data *e_data, + void *client_data) +{ + struct vmci_transport *trans = client_data; + const struct vmci_event_payload_qp *e_payload; + + e_payload = vmci_event_data_const_payload(e_data); + + /* XXX This is lame, we should provide a way to lookup sockets by + * qp_handle. + */ + if (vmci_handle_is_invalid(e_payload->handle) || + !vmci_handle_is_equal(trans->qp_handle, e_payload->handle)) + return; + + /* We don't ask for delayed CBs when we subscribe to this event (we + * pass 0 as flags to vmci_event_subscribe()). VMCI makes no + * guarantees in that case about what context we might be running in, + * so it could be BH or process, blockable or non-blockable. So we + * need to account for all possible contexts here. + */ + spin_lock_bh(&trans->lock); + if (!trans->sk) + goto out; + + /* Apart from here, trans->lock is only grabbed as part of sk destruct, + * where trans->sk isn't locked. + */ + bh_lock_sock(trans->sk); + + vmci_transport_handle_detach(trans->sk); + + bh_unlock_sock(trans->sk); + out: + spin_unlock_bh(&trans->lock); +} + +static void vmci_transport_qp_resumed_cb(u32 sub_id, + const struct vmci_event_data *e_data, + void *client_data) +{ + vsock_for_each_connected_socket(&vmci_transport, + vmci_transport_handle_detach); +} + +static void vmci_transport_recv_pkt_work(struct work_struct *work) +{ + struct vmci_transport_recv_pkt_info *recv_pkt_info; + struct vmci_transport_packet *pkt; + struct sock *sk; + + recv_pkt_info = + container_of(work, struct vmci_transport_recv_pkt_info, work); + sk = recv_pkt_info->sk; + pkt = &recv_pkt_info->pkt; + + lock_sock(sk); + + /* The local context ID may be out of date. */ + vsock_sk(sk)->local_addr.svm_cid = pkt->dg.dst.context; + + switch (sk->sk_state) { + case TCP_LISTEN: + vmci_transport_recv_listen(sk, pkt); + break; + case TCP_SYN_SENT: + /* Processing of pending connections for servers goes through + * the listening socket, so see vmci_transport_recv_listen() + * for that path. + */ + vmci_transport_recv_connecting_client(sk, pkt); + break; + case TCP_ESTABLISHED: + vmci_transport_recv_connected(sk, pkt); + break; + default: + /* Because this function does not run in the same context as + * vmci_transport_recv_stream_cb it is possible that the + * socket has closed. We need to let the other side know or it + * could be sitting in a connect and hang forever. Send a + * reset to prevent that. + */ + vmci_transport_send_reset(sk, pkt); + break; + } + + release_sock(sk); + kfree(recv_pkt_info); + /* Release reference obtained in the stream callback when we fetched + * this socket out of the bound or connected list. + */ + sock_put(sk); +} + +static int vmci_transport_recv_listen(struct sock *sk, + struct vmci_transport_packet *pkt) +{ + struct sock *pending; + struct vsock_sock *vpending; + int err; + u64 qp_size; + bool old_request = false; + bool old_pkt_proto = false; + + err = 0; + + /* Because we are in the listen state, we could be receiving a packet + * for ourself or any previous connection requests that we received. + * If it's the latter, we try to find a socket in our list of pending + * connections and, if we do, call the appropriate handler for the + * state that that socket is in. Otherwise we try to service the + * connection request. + */ + pending = vmci_transport_get_pending(sk, pkt); + if (pending) { + lock_sock(pending); + + /* The local context ID may be out of date. */ + vsock_sk(pending)->local_addr.svm_cid = pkt->dg.dst.context; + + switch (pending->sk_state) { + case TCP_SYN_SENT: + err = vmci_transport_recv_connecting_server(sk, + pending, + pkt); + break; + default: + vmci_transport_send_reset(pending, pkt); + err = -EINVAL; + } + + if (err < 0) + vsock_remove_pending(sk, pending); + + release_sock(pending); + vmci_transport_release_pending(pending); + + return err; + } + + /* The listen state only accepts connection requests. Reply with a + * reset unless we received a reset. + */ + + if (!(pkt->type == VMCI_TRANSPORT_PACKET_TYPE_REQUEST || + pkt->type == VMCI_TRANSPORT_PACKET_TYPE_REQUEST2)) { + vmci_transport_reply_reset(pkt); + return -EINVAL; + } + + if (pkt->u.size == 0) { + vmci_transport_reply_reset(pkt); + return -EINVAL; + } + + /* If this socket can't accommodate this connection request, we send a + * reset. Otherwise we create and initialize a child socket and reply + * with a connection negotiation. + */ + if (sk->sk_ack_backlog >= sk->sk_max_ack_backlog) { + vmci_transport_reply_reset(pkt); + return -ECONNREFUSED; + } + + pending = vsock_create_connected(sk); + if (!pending) { + vmci_transport_send_reset(sk, pkt); + return -ENOMEM; + } + + vpending = vsock_sk(pending); + + vsock_addr_init(&vpending->local_addr, pkt->dg.dst.context, + pkt->dst_port); + vsock_addr_init(&vpending->remote_addr, pkt->dg.src.context, + pkt->src_port); + + err = vsock_assign_transport(vpending, vsock_sk(sk)); + /* Transport assigned (looking at remote_addr) must be the same + * where we received the request. + */ + if (err || !vmci_check_transport(vpending)) { + vmci_transport_send_reset(sk, pkt); + sock_put(pending); + return err; + } + + /* If the proposed size fits within our min/max, accept it. Otherwise + * propose our own size. + */ + if (pkt->u.size >= vpending->buffer_min_size && + pkt->u.size <= vpending->buffer_max_size) { + qp_size = pkt->u.size; + } else { + qp_size = vpending->buffer_size; + } + + /* Figure out if we are using old or new requests based on the + * overrides pkt types sent by our peer. + */ + if (vmci_transport_old_proto_override(&old_pkt_proto)) { + old_request = old_pkt_proto; + } else { + if (pkt->type == VMCI_TRANSPORT_PACKET_TYPE_REQUEST) + old_request = true; + else if (pkt->type == VMCI_TRANSPORT_PACKET_TYPE_REQUEST2) + old_request = false; + + } + + if (old_request) { + /* Handle a REQUEST (or override) */ + u16 version = VSOCK_PROTO_INVALID; + if (vmci_transport_proto_to_notify_struct( + pending, &version, true)) + err = vmci_transport_send_negotiate(pending, qp_size); + else + err = -EINVAL; + + } else { + /* Handle a REQUEST2 (or override) */ + int proto_int = pkt->proto; + int pos; + u16 active_proto_version = 0; + + /* The list of possible protocols is the intersection of all + * protocols the client supports ... plus all the protocols we + * support. + */ + proto_int &= vmci_transport_new_proto_supported_versions(); + + /* We choose the highest possible protocol version and use that + * one. + */ + pos = fls(proto_int); + if (pos) { + active_proto_version = (1 << (pos - 1)); + if (vmci_transport_proto_to_notify_struct( + pending, &active_proto_version, false)) + err = vmci_transport_send_negotiate2(pending, + qp_size, + active_proto_version); + else + err = -EINVAL; + + } else { + err = -EINVAL; + } + } + + if (err < 0) { + vmci_transport_send_reset(sk, pkt); + sock_put(pending); + err = vmci_transport_error_to_vsock_error(err); + goto out; + } + + vsock_add_pending(sk, pending); + sk_acceptq_added(sk); + + pending->sk_state = TCP_SYN_SENT; + vmci_trans(vpending)->produce_size = + vmci_trans(vpending)->consume_size = qp_size; + vpending->buffer_size = qp_size; + + vmci_trans(vpending)->notify_ops->process_request(pending); + + /* We might never receive another message for this socket and it's not + * connected to any process, so we have to ensure it gets cleaned up + * ourself. Our delayed work function will take care of that. Note + * that we do not ever cancel this function since we have few + * guarantees about its state when calling cancel_delayed_work(). + * Instead we hold a reference on the socket for that function and make + * it capable of handling cases where it needs to do nothing but + * release that reference. + */ + vpending->listener = sk; + sock_hold(sk); + sock_hold(pending); + schedule_delayed_work(&vpending->pending_work, HZ); + +out: + return err; +} + +static int +vmci_transport_recv_connecting_server(struct sock *listener, + struct sock *pending, + struct vmci_transport_packet *pkt) +{ + struct vsock_sock *vpending; + struct vmci_handle handle; + struct vmci_qp *qpair; + bool is_local; + u32 flags; + u32 detach_sub_id; + int err; + int skerr; + + vpending = vsock_sk(pending); + detach_sub_id = VMCI_INVALID_ID; + + switch (pkt->type) { + case VMCI_TRANSPORT_PACKET_TYPE_OFFER: + if (vmci_handle_is_invalid(pkt->u.handle)) { + vmci_transport_send_reset(pending, pkt); + skerr = EPROTO; + err = -EINVAL; + goto destroy; + } + break; + default: + /* Close and cleanup the connection. */ + vmci_transport_send_reset(pending, pkt); + skerr = EPROTO; + err = pkt->type == VMCI_TRANSPORT_PACKET_TYPE_RST ? 0 : -EINVAL; + goto destroy; + } + + /* In order to complete the connection we need to attach to the offered + * queue pair and send an attach notification. We also subscribe to the + * detach event so we know when our peer goes away, and we do that + * before attaching so we don't miss an event. If all this succeeds, + * we update our state and wakeup anything waiting in accept() for a + * connection. + */ + + /* We don't care about attach since we ensure the other side has + * attached by specifying the ATTACH_ONLY flag below. + */ + err = vmci_event_subscribe(VMCI_EVENT_QP_PEER_DETACH, + vmci_transport_peer_detach_cb, + vmci_trans(vpending), &detach_sub_id); + if (err < VMCI_SUCCESS) { + vmci_transport_send_reset(pending, pkt); + err = vmci_transport_error_to_vsock_error(err); + skerr = -err; + goto destroy; + } + + vmci_trans(vpending)->detach_sub_id = detach_sub_id; + + /* Now attach to the queue pair the client created. */ + handle = pkt->u.handle; + + /* vpending->local_addr always has a context id so we do not need to + * worry about VMADDR_CID_ANY in this case. + */ + is_local = + vpending->remote_addr.svm_cid == vpending->local_addr.svm_cid; + flags = VMCI_QPFLAG_ATTACH_ONLY; + flags |= is_local ? VMCI_QPFLAG_LOCAL : 0; + + err = vmci_transport_queue_pair_alloc( + &qpair, + &handle, + vmci_trans(vpending)->produce_size, + vmci_trans(vpending)->consume_size, + pkt->dg.src.context, + flags, + vmci_transport_is_trusted( + vpending, + vpending->remote_addr.svm_cid)); + if (err < 0) { + vmci_transport_send_reset(pending, pkt); + skerr = -err; + goto destroy; + } + + vmci_trans(vpending)->qp_handle = handle; + vmci_trans(vpending)->qpair = qpair; + + /* When we send the attach message, we must be ready to handle incoming + * control messages on the newly connected socket. So we move the + * pending socket to the connected state before sending the attach + * message. Otherwise, an incoming packet triggered by the attach being + * received by the peer may be processed concurrently with what happens + * below after sending the attach message, and that incoming packet + * will find the listening socket instead of the (currently) pending + * socket. Note that enqueueing the socket increments the reference + * count, so even if a reset comes before the connection is accepted, + * the socket will be valid until it is removed from the queue. + * + * If we fail sending the attach below, we remove the socket from the + * connected list and move the socket to TCP_CLOSE before + * releasing the lock, so a pending slow path processing of an incoming + * packet will not see the socket in the connected state in that case. + */ + pending->sk_state = TCP_ESTABLISHED; + + vsock_insert_connected(vpending); + + /* Notify our peer of our attach. */ + err = vmci_transport_send_attach(pending, handle); + if (err < 0) { + vsock_remove_connected(vpending); + pr_err("Could not send attach\n"); + vmci_transport_send_reset(pending, pkt); + err = vmci_transport_error_to_vsock_error(err); + skerr = -err; + goto destroy; + } + + /* We have a connection. Move the now connected socket from the + * listener's pending list to the accept queue so callers of accept() + * can find it. + */ + vsock_remove_pending(listener, pending); + vsock_enqueue_accept(listener, pending); + + /* Callers of accept() will be be waiting on the listening socket, not + * the pending socket. + */ + listener->sk_data_ready(listener); + + return 0; + +destroy: + pending->sk_err = skerr; + pending->sk_state = TCP_CLOSE; + /* As long as we drop our reference, all necessary cleanup will handle + * when the cleanup function drops its reference and our destruct + * implementation is called. Note that since the listen handler will + * remove pending from the pending list upon our failure, the cleanup + * function won't drop the additional reference, which is why we do it + * here. + */ + sock_put(pending); + + return err; +} + +static int +vmci_transport_recv_connecting_client(struct sock *sk, + struct vmci_transport_packet *pkt) +{ + struct vsock_sock *vsk; + int err; + int skerr; + + vsk = vsock_sk(sk); + + switch (pkt->type) { + case VMCI_TRANSPORT_PACKET_TYPE_ATTACH: + if (vmci_handle_is_invalid(pkt->u.handle) || + !vmci_handle_is_equal(pkt->u.handle, + vmci_trans(vsk)->qp_handle)) { + skerr = EPROTO; + err = -EINVAL; + goto destroy; + } + + /* Signify the socket is connected and wakeup the waiter in + * connect(). Also place the socket in the connected table for + * accounting (it can already be found since it's in the bound + * table). + */ + sk->sk_state = TCP_ESTABLISHED; + sk->sk_socket->state = SS_CONNECTED; + vsock_insert_connected(vsk); + sk->sk_state_change(sk); + + break; + case VMCI_TRANSPORT_PACKET_TYPE_NEGOTIATE: + case VMCI_TRANSPORT_PACKET_TYPE_NEGOTIATE2: + if (pkt->u.size == 0 + || pkt->dg.src.context != vsk->remote_addr.svm_cid + || pkt->src_port != vsk->remote_addr.svm_port + || !vmci_handle_is_invalid(vmci_trans(vsk)->qp_handle) + || vmci_trans(vsk)->qpair + || vmci_trans(vsk)->produce_size != 0 + || vmci_trans(vsk)->consume_size != 0 + || vmci_trans(vsk)->detach_sub_id != VMCI_INVALID_ID) { + skerr = EPROTO; + err = -EINVAL; + + goto destroy; + } + + err = vmci_transport_recv_connecting_client_negotiate(sk, pkt); + if (err) { + skerr = -err; + goto destroy; + } + + break; + case VMCI_TRANSPORT_PACKET_TYPE_INVALID: + err = vmci_transport_recv_connecting_client_invalid(sk, pkt); + if (err) { + skerr = -err; + goto destroy; + } + + break; + case VMCI_TRANSPORT_PACKET_TYPE_RST: + /* Older versions of the linux code (WS 6.5 / ESX 4.0) used to + * continue processing here after they sent an INVALID packet. + * This meant that we got a RST after the INVALID. We ignore a + * RST after an INVALID. The common code doesn't send the RST + * ... so we can hang if an old version of the common code + * fails between getting a REQUEST and sending an OFFER back. + * Not much we can do about it... except hope that it doesn't + * happen. + */ + if (vsk->ignore_connecting_rst) { + vsk->ignore_connecting_rst = false; + } else { + skerr = ECONNRESET; + err = 0; + goto destroy; + } + + break; + default: + /* Close and cleanup the connection. */ + skerr = EPROTO; + err = -EINVAL; + goto destroy; + } + + return 0; + +destroy: + vmci_transport_send_reset(sk, pkt); + + sk->sk_state = TCP_CLOSE; + sk->sk_err = skerr; + sk->sk_error_report(sk); + return err; +} + +static int vmci_transport_recv_connecting_client_negotiate( + struct sock *sk, + struct vmci_transport_packet *pkt) +{ + int err; + struct vsock_sock *vsk; + struct vmci_handle handle; + struct vmci_qp *qpair; + u32 detach_sub_id; + bool is_local; + u32 flags; + bool old_proto = true; + bool old_pkt_proto; + u16 version; + + vsk = vsock_sk(sk); + handle = VMCI_INVALID_HANDLE; + detach_sub_id = VMCI_INVALID_ID; + + /* If we have gotten here then we should be past the point where old + * linux vsock could have sent the bogus rst. + */ + vsk->sent_request = false; + vsk->ignore_connecting_rst = false; + + /* Verify that we're OK with the proposed queue pair size */ + if (pkt->u.size < vsk->buffer_min_size || + pkt->u.size > vsk->buffer_max_size) { + err = -EINVAL; + goto destroy; + } + + /* At this point we know the CID the peer is using to talk to us. */ + + if (vsk->local_addr.svm_cid == VMADDR_CID_ANY) + vsk->local_addr.svm_cid = pkt->dg.dst.context; + + /* Setup the notify ops to be the highest supported version that both + * the server and the client support. + */ + + if (vmci_transport_old_proto_override(&old_pkt_proto)) { + old_proto = old_pkt_proto; + } else { + if (pkt->type == VMCI_TRANSPORT_PACKET_TYPE_NEGOTIATE) + old_proto = true; + else if (pkt->type == VMCI_TRANSPORT_PACKET_TYPE_NEGOTIATE2) + old_proto = false; + + } + + if (old_proto) + version = VSOCK_PROTO_INVALID; + else + version = pkt->proto; + + if (!vmci_transport_proto_to_notify_struct(sk, &version, old_proto)) { + err = -EINVAL; + goto destroy; + } + + /* Subscribe to detach events first. + * + * XXX We attach once for each queue pair created for now so it is easy + * to find the socket (it's provided), but later we should only + * subscribe once and add a way to lookup sockets by queue pair handle. + */ + err = vmci_event_subscribe(VMCI_EVENT_QP_PEER_DETACH, + vmci_transport_peer_detach_cb, + vmci_trans(vsk), &detach_sub_id); + if (err < VMCI_SUCCESS) { + err = vmci_transport_error_to_vsock_error(err); + goto destroy; + } + + /* Make VMCI select the handle for us. */ + handle = VMCI_INVALID_HANDLE; + is_local = vsk->remote_addr.svm_cid == vsk->local_addr.svm_cid; + flags = is_local ? VMCI_QPFLAG_LOCAL : 0; + + err = vmci_transport_queue_pair_alloc(&qpair, + &handle, + pkt->u.size, + pkt->u.size, + vsk->remote_addr.svm_cid, + flags, + vmci_transport_is_trusted( + vsk, + vsk-> + remote_addr.svm_cid)); + if (err < 0) + goto destroy; + + err = vmci_transport_send_qp_offer(sk, handle); + if (err < 0) { + err = vmci_transport_error_to_vsock_error(err); + goto destroy; + } + + vmci_trans(vsk)->qp_handle = handle; + vmci_trans(vsk)->qpair = qpair; + + vmci_trans(vsk)->produce_size = vmci_trans(vsk)->consume_size = + pkt->u.size; + + vmci_trans(vsk)->detach_sub_id = detach_sub_id; + + vmci_trans(vsk)->notify_ops->process_negotiate(sk); + + return 0; + +destroy: + if (detach_sub_id != VMCI_INVALID_ID) + vmci_event_unsubscribe(detach_sub_id); + + if (!vmci_handle_is_invalid(handle)) + vmci_qpair_detach(&qpair); + + return err; +} + +static int +vmci_transport_recv_connecting_client_invalid(struct sock *sk, + struct vmci_transport_packet *pkt) +{ + int err = 0; + struct vsock_sock *vsk = vsock_sk(sk); + + if (vsk->sent_request) { + vsk->sent_request = false; + vsk->ignore_connecting_rst = true; + + err = vmci_transport_send_conn_request(sk, vsk->buffer_size); + if (err < 0) + err = vmci_transport_error_to_vsock_error(err); + else + err = 0; + + } + + return err; +} + +static int vmci_transport_recv_connected(struct sock *sk, + struct vmci_transport_packet *pkt) +{ + struct vsock_sock *vsk; + bool pkt_processed = false; + + /* In cases where we are closing the connection, it's sufficient to + * mark the state change (and maybe error) and wake up any waiting + * threads. Since this is a connected socket, it's owned by a user + * process and will be cleaned up when the failure is passed back on + * the current or next system call. Our system call implementations + * must therefore check for error and state changes on entry and when + * being awoken. + */ + switch (pkt->type) { + case VMCI_TRANSPORT_PACKET_TYPE_SHUTDOWN: + if (pkt->u.mode) { + vsk = vsock_sk(sk); + + vsk->peer_shutdown |= pkt->u.mode; + sk->sk_state_change(sk); + } + break; + + case VMCI_TRANSPORT_PACKET_TYPE_RST: + vsk = vsock_sk(sk); + /* It is possible that we sent our peer a message (e.g a + * WAITING_READ) right before we got notified that the peer had + * detached. If that happens then we can get a RST pkt back + * from our peer even though there is data available for us to + * read. In that case, don't shutdown the socket completely but + * instead allow the local client to finish reading data off + * the queuepair. Always treat a RST pkt in connected mode like + * a clean shutdown. + */ + sock_set_flag(sk, SOCK_DONE); + vsk->peer_shutdown = SHUTDOWN_MASK; + if (vsock_stream_has_data(vsk) <= 0) + sk->sk_state = TCP_CLOSING; + + sk->sk_state_change(sk); + break; + + default: + vsk = vsock_sk(sk); + vmci_trans(vsk)->notify_ops->handle_notify_pkt( + sk, pkt, false, NULL, NULL, + &pkt_processed); + if (!pkt_processed) + return -EINVAL; + + break; + } + + return 0; +} + +static int vmci_transport_socket_init(struct vsock_sock *vsk, + struct vsock_sock *psk) +{ + vsk->trans = kmalloc(sizeof(struct vmci_transport), GFP_KERNEL); + if (!vsk->trans) + return -ENOMEM; + + vmci_trans(vsk)->dg_handle = VMCI_INVALID_HANDLE; + vmci_trans(vsk)->qp_handle = VMCI_INVALID_HANDLE; + vmci_trans(vsk)->qpair = NULL; + vmci_trans(vsk)->produce_size = vmci_trans(vsk)->consume_size = 0; + vmci_trans(vsk)->detach_sub_id = VMCI_INVALID_ID; + vmci_trans(vsk)->notify_ops = NULL; + INIT_LIST_HEAD(&vmci_trans(vsk)->elem); + vmci_trans(vsk)->sk = &vsk->sk; + spin_lock_init(&vmci_trans(vsk)->lock); + + return 0; +} + +static void vmci_transport_free_resources(struct list_head *transport_list) +{ + while (!list_empty(transport_list)) { + struct vmci_transport *transport = + list_first_entry(transport_list, struct vmci_transport, + elem); + list_del(&transport->elem); + + if (transport->detach_sub_id != VMCI_INVALID_ID) { + vmci_event_unsubscribe(transport->detach_sub_id); + transport->detach_sub_id = VMCI_INVALID_ID; + } + + if (!vmci_handle_is_invalid(transport->qp_handle)) { + vmci_qpair_detach(&transport->qpair); + transport->qp_handle = VMCI_INVALID_HANDLE; + transport->produce_size = 0; + transport->consume_size = 0; + } + + kfree(transport); + } +} + +static void vmci_transport_cleanup(struct work_struct *work) +{ + LIST_HEAD(pending); + + spin_lock_bh(&vmci_transport_cleanup_lock); + list_replace_init(&vmci_transport_cleanup_list, &pending); + spin_unlock_bh(&vmci_transport_cleanup_lock); + vmci_transport_free_resources(&pending); +} + +static void vmci_transport_destruct(struct vsock_sock *vsk) +{ + /* transport can be NULL if we hit a failure at init() time */ + if (!vmci_trans(vsk)) + return; + + /* Ensure that the detach callback doesn't use the sk/vsk + * we are about to destruct. + */ + spin_lock_bh(&vmci_trans(vsk)->lock); + vmci_trans(vsk)->sk = NULL; + spin_unlock_bh(&vmci_trans(vsk)->lock); + + if (vmci_trans(vsk)->notify_ops) + vmci_trans(vsk)->notify_ops->socket_destruct(vsk); + + spin_lock_bh(&vmci_transport_cleanup_lock); + list_add(&vmci_trans(vsk)->elem, &vmci_transport_cleanup_list); + spin_unlock_bh(&vmci_transport_cleanup_lock); + schedule_work(&vmci_transport_cleanup_work); + + vsk->trans = NULL; +} + +static void vmci_transport_release(struct vsock_sock *vsk) +{ + vsock_remove_sock(vsk); + + if (!vmci_handle_is_invalid(vmci_trans(vsk)->dg_handle)) { + vmci_datagram_destroy_handle(vmci_trans(vsk)->dg_handle); + vmci_trans(vsk)->dg_handle = VMCI_INVALID_HANDLE; + } +} + +static int vmci_transport_dgram_bind(struct vsock_sock *vsk, + struct sockaddr_vm *addr) +{ + u32 port; + u32 flags; + int err; + + /* VMCI will select a resource ID for us if we provide + * VMCI_INVALID_ID. + */ + port = addr->svm_port == VMADDR_PORT_ANY ? + VMCI_INVALID_ID : addr->svm_port; + + if (port <= LAST_RESERVED_PORT && !capable(CAP_NET_BIND_SERVICE)) + return -EACCES; + + flags = addr->svm_cid == VMADDR_CID_ANY ? + VMCI_FLAG_ANYCID_DG_HND : 0; + + err = vmci_transport_datagram_create_hnd(port, flags, + vmci_transport_recv_dgram_cb, + &vsk->sk, + &vmci_trans(vsk)->dg_handle); + if (err < VMCI_SUCCESS) + return vmci_transport_error_to_vsock_error(err); + vsock_addr_init(&vsk->local_addr, addr->svm_cid, + vmci_trans(vsk)->dg_handle.resource); + + return 0; +} + +static int vmci_transport_dgram_enqueue( + struct vsock_sock *vsk, + struct sockaddr_vm *remote_addr, + struct msghdr *msg, + size_t len) +{ + int err; + struct vmci_datagram *dg; + + if (len > VMCI_MAX_DG_PAYLOAD_SIZE) + return -EMSGSIZE; + + if (!vmci_transport_allow_dgram(vsk, remote_addr->svm_cid)) + return -EPERM; + + /* Allocate a buffer for the user's message and our packet header. */ + dg = kmalloc(len + sizeof(*dg), GFP_KERNEL); + if (!dg) + return -ENOMEM; + + err = memcpy_from_msg(VMCI_DG_PAYLOAD(dg), msg, len); + if (err) { + kfree(dg); + return err; + } + + dg->dst = vmci_make_handle(remote_addr->svm_cid, + remote_addr->svm_port); + dg->src = vmci_make_handle(vsk->local_addr.svm_cid, + vsk->local_addr.svm_port); + dg->payload_size = len; + + err = vmci_datagram_send(dg); + kfree(dg); + if (err < 0) + return vmci_transport_error_to_vsock_error(err); + + return err - sizeof(*dg); +} + +static int vmci_transport_dgram_dequeue(struct vsock_sock *vsk, + struct msghdr *msg, size_t len, + int flags) +{ + int err; + int noblock; + struct vmci_datagram *dg; + size_t payload_len; + struct sk_buff *skb; + + noblock = flags & MSG_DONTWAIT; + + if (flags & MSG_OOB || flags & MSG_ERRQUEUE) + return -EOPNOTSUPP; + + /* Retrieve the head sk_buff from the socket's receive queue. */ + err = 0; + skb = skb_recv_datagram(&vsk->sk, flags, noblock, &err); + if (!skb) + return err; + + dg = (struct vmci_datagram *)skb->data; + if (!dg) + /* err is 0, meaning we read zero bytes. */ + goto out; + + payload_len = dg->payload_size; + /* Ensure the sk_buff matches the payload size claimed in the packet. */ + if (payload_len != skb->len - sizeof(*dg)) { + err = -EINVAL; + goto out; + } + + if (payload_len > len) { + payload_len = len; + msg->msg_flags |= MSG_TRUNC; + } + + /* Place the datagram payload in the user's iovec. */ + err = skb_copy_datagram_msg(skb, sizeof(*dg), msg, payload_len); + if (err) + goto out; + + if (msg->msg_name) { + /* Provide the address of the sender. */ + DECLARE_SOCKADDR(struct sockaddr_vm *, vm_addr, msg->msg_name); + vsock_addr_init(vm_addr, dg->src.context, dg->src.resource); + msg->msg_namelen = sizeof(*vm_addr); + } + err = payload_len; + +out: + skb_free_datagram(&vsk->sk, skb); + return err; +} + +static bool vmci_transport_dgram_allow(u32 cid, u32 port) +{ + if (cid == VMADDR_CID_HYPERVISOR) { + /* Registrations of PBRPC Servers do not modify VMX/Hypervisor + * state and are allowed. + */ + return port == VMCI_UNITY_PBRPC_REGISTER; + } + + return true; +} + +static int vmci_transport_connect(struct vsock_sock *vsk) +{ + int err; + bool old_pkt_proto = false; + struct sock *sk = &vsk->sk; + + if (vmci_transport_old_proto_override(&old_pkt_proto) && + old_pkt_proto) { + err = vmci_transport_send_conn_request(sk, vsk->buffer_size); + if (err < 0) { + sk->sk_state = TCP_CLOSE; + return err; + } + } else { + int supported_proto_versions = + vmci_transport_new_proto_supported_versions(); + err = vmci_transport_send_conn_request2(sk, vsk->buffer_size, + supported_proto_versions); + if (err < 0) { + sk->sk_state = TCP_CLOSE; + return err; + } + + vsk->sent_request = true; + } + + return err; +} + +static ssize_t vmci_transport_stream_dequeue( + struct vsock_sock *vsk, + struct msghdr *msg, + size_t len, + int flags) +{ + if (flags & MSG_PEEK) + return vmci_qpair_peekv(vmci_trans(vsk)->qpair, msg, len, 0); + else + return vmci_qpair_dequev(vmci_trans(vsk)->qpair, msg, len, 0); +} + +static ssize_t vmci_transport_stream_enqueue( + struct vsock_sock *vsk, + struct msghdr *msg, + size_t len) +{ + return vmci_qpair_enquev(vmci_trans(vsk)->qpair, msg, len, 0); +} + +static s64 vmci_transport_stream_has_data(struct vsock_sock *vsk) +{ + return vmci_qpair_consume_buf_ready(vmci_trans(vsk)->qpair); +} + +static s64 vmci_transport_stream_has_space(struct vsock_sock *vsk) +{ + return vmci_qpair_produce_free_space(vmci_trans(vsk)->qpair); +} + +static u64 vmci_transport_stream_rcvhiwat(struct vsock_sock *vsk) +{ + return vmci_trans(vsk)->consume_size; +} + +static bool vmci_transport_stream_is_active(struct vsock_sock *vsk) +{ + return !vmci_handle_is_invalid(vmci_trans(vsk)->qp_handle); +} + +static int vmci_transport_notify_poll_in( + struct vsock_sock *vsk, + size_t target, + bool *data_ready_now) +{ + return vmci_trans(vsk)->notify_ops->poll_in( + &vsk->sk, target, data_ready_now); +} + +static int vmci_transport_notify_poll_out( + struct vsock_sock *vsk, + size_t target, + bool *space_available_now) +{ + return vmci_trans(vsk)->notify_ops->poll_out( + &vsk->sk, target, space_available_now); +} + +static int vmci_transport_notify_recv_init( + struct vsock_sock *vsk, + size_t target, + struct vsock_transport_recv_notify_data *data) +{ + return vmci_trans(vsk)->notify_ops->recv_init( + &vsk->sk, target, + (struct vmci_transport_recv_notify_data *)data); +} + +static int vmci_transport_notify_recv_pre_block( + struct vsock_sock *vsk, + size_t target, + struct vsock_transport_recv_notify_data *data) +{ + return vmci_trans(vsk)->notify_ops->recv_pre_block( + &vsk->sk, target, + (struct vmci_transport_recv_notify_data *)data); +} + +static int vmci_transport_notify_recv_pre_dequeue( + struct vsock_sock *vsk, + size_t target, + struct vsock_transport_recv_notify_data *data) +{ + return vmci_trans(vsk)->notify_ops->recv_pre_dequeue( + &vsk->sk, target, + (struct vmci_transport_recv_notify_data *)data); +} + +static int vmci_transport_notify_recv_post_dequeue( + struct vsock_sock *vsk, + size_t target, + ssize_t copied, + bool data_read, + struct vsock_transport_recv_notify_data *data) +{ + return vmci_trans(vsk)->notify_ops->recv_post_dequeue( + &vsk->sk, target, copied, data_read, + (struct vmci_transport_recv_notify_data *)data); +} + +static int vmci_transport_notify_send_init( + struct vsock_sock *vsk, + struct vsock_transport_send_notify_data *data) +{ + return vmci_trans(vsk)->notify_ops->send_init( + &vsk->sk, + (struct vmci_transport_send_notify_data *)data); +} + +static int vmci_transport_notify_send_pre_block( + struct vsock_sock *vsk, + struct vsock_transport_send_notify_data *data) +{ + return vmci_trans(vsk)->notify_ops->send_pre_block( + &vsk->sk, + (struct vmci_transport_send_notify_data *)data); +} + +static int vmci_transport_notify_send_pre_enqueue( + struct vsock_sock *vsk, + struct vsock_transport_send_notify_data *data) +{ + return vmci_trans(vsk)->notify_ops->send_pre_enqueue( + &vsk->sk, + (struct vmci_transport_send_notify_data *)data); +} + +static int vmci_transport_notify_send_post_enqueue( + struct vsock_sock *vsk, + ssize_t written, + struct vsock_transport_send_notify_data *data) +{ + return vmci_trans(vsk)->notify_ops->send_post_enqueue( + &vsk->sk, written, + (struct vmci_transport_send_notify_data *)data); +} + +static bool vmci_transport_old_proto_override(bool *old_pkt_proto) +{ + if (PROTOCOL_OVERRIDE != -1) { + if (PROTOCOL_OVERRIDE == 0) + *old_pkt_proto = true; + else + *old_pkt_proto = false; + + pr_info("Proto override in use\n"); + return true; + } + + return false; +} + +static bool vmci_transport_proto_to_notify_struct(struct sock *sk, + u16 *proto, + bool old_pkt_proto) +{ + struct vsock_sock *vsk = vsock_sk(sk); + + if (old_pkt_proto) { + if (*proto != VSOCK_PROTO_INVALID) { + pr_err("Can't set both an old and new protocol\n"); + return false; + } + vmci_trans(vsk)->notify_ops = &vmci_transport_notify_pkt_ops; + goto exit; + } + + switch (*proto) { + case VSOCK_PROTO_PKT_ON_NOTIFY: + vmci_trans(vsk)->notify_ops = + &vmci_transport_notify_pkt_q_state_ops; + break; + default: + pr_err("Unknown notify protocol version\n"); + return false; + } + +exit: + vmci_trans(vsk)->notify_ops->socket_init(sk); + return true; +} + +static u16 vmci_transport_new_proto_supported_versions(void) +{ + if (PROTOCOL_OVERRIDE != -1) + return PROTOCOL_OVERRIDE; + + return VSOCK_PROTO_ALL_SUPPORTED; +} + +static u32 vmci_transport_get_local_cid(void) +{ + return vmci_get_context_id(); +} + +static struct vsock_transport vmci_transport = { + .module = THIS_MODULE, + .init = vmci_transport_socket_init, + .destruct = vmci_transport_destruct, + .release = vmci_transport_release, + .connect = vmci_transport_connect, + .dgram_bind = vmci_transport_dgram_bind, + .dgram_dequeue = vmci_transport_dgram_dequeue, + .dgram_enqueue = vmci_transport_dgram_enqueue, + .dgram_allow = vmci_transport_dgram_allow, + .stream_dequeue = vmci_transport_stream_dequeue, + .stream_enqueue = vmci_transport_stream_enqueue, + .stream_has_data = vmci_transport_stream_has_data, + .stream_has_space = vmci_transport_stream_has_space, + .stream_rcvhiwat = vmci_transport_stream_rcvhiwat, + .stream_is_active = vmci_transport_stream_is_active, + .stream_allow = vmci_transport_stream_allow, + .notify_poll_in = vmci_transport_notify_poll_in, + .notify_poll_out = vmci_transport_notify_poll_out, + .notify_recv_init = vmci_transport_notify_recv_init, + .notify_recv_pre_block = vmci_transport_notify_recv_pre_block, + .notify_recv_pre_dequeue = vmci_transport_notify_recv_pre_dequeue, + .notify_recv_post_dequeue = vmci_transport_notify_recv_post_dequeue, + .notify_send_init = vmci_transport_notify_send_init, + .notify_send_pre_block = vmci_transport_notify_send_pre_block, + .notify_send_pre_enqueue = vmci_transport_notify_send_pre_enqueue, + .notify_send_post_enqueue = vmci_transport_notify_send_post_enqueue, + .shutdown = vmci_transport_shutdown, + .get_local_cid = vmci_transport_get_local_cid, +}; + +static bool vmci_check_transport(struct vsock_sock *vsk) +{ + return vsk->transport == &vmci_transport; +} + +static void vmci_vsock_transport_cb(bool is_host) +{ + int features; + + if (is_host) + features = VSOCK_TRANSPORT_F_H2G; + else + features = VSOCK_TRANSPORT_F_G2H; + + vsock_core_register(&vmci_transport, features); +} + +static int __init vmci_transport_init(void) +{ + int err; + + /* Create the datagram handle that we will use to send and receive all + * VSocket control messages for this context. + */ + err = vmci_transport_datagram_create_hnd(VMCI_TRANSPORT_PACKET_RID, + VMCI_FLAG_ANYCID_DG_HND, + vmci_transport_recv_stream_cb, + NULL, + &vmci_transport_stream_handle); + if (err < VMCI_SUCCESS) { + pr_err("Unable to create datagram handle. (%d)\n", err); + return vmci_transport_error_to_vsock_error(err); + } + err = vmci_event_subscribe(VMCI_EVENT_QP_RESUMED, + vmci_transport_qp_resumed_cb, + NULL, &vmci_transport_qp_resumed_sub_id); + if (err < VMCI_SUCCESS) { + pr_err("Unable to subscribe to resumed event. (%d)\n", err); + err = vmci_transport_error_to_vsock_error(err); + vmci_transport_qp_resumed_sub_id = VMCI_INVALID_ID; + goto err_destroy_stream_handle; + } + + /* Register only with dgram feature, other features (H2G, G2H) will be + * registered when the first host or guest becomes active. + */ + err = vsock_core_register(&vmci_transport, VSOCK_TRANSPORT_F_DGRAM); + if (err < 0) + goto err_unsubscribe; + + err = vmci_register_vsock_callback(vmci_vsock_transport_cb); + if (err < 0) + goto err_unregister; + + return 0; + +err_unregister: + vsock_core_unregister(&vmci_transport); +err_unsubscribe: + vmci_event_unsubscribe(vmci_transport_qp_resumed_sub_id); +err_destroy_stream_handle: + vmci_datagram_destroy_handle(vmci_transport_stream_handle); + return err; +} +module_init(vmci_transport_init); + +static void __exit vmci_transport_exit(void) +{ + cancel_work_sync(&vmci_transport_cleanup_work); + vmci_transport_free_resources(&vmci_transport_cleanup_list); + + if (!vmci_handle_is_invalid(vmci_transport_stream_handle)) { + if (vmci_datagram_destroy_handle( + vmci_transport_stream_handle) != VMCI_SUCCESS) + pr_err("Couldn't destroy datagram handle\n"); + vmci_transport_stream_handle = VMCI_INVALID_HANDLE; + } + + if (vmci_transport_qp_resumed_sub_id != VMCI_INVALID_ID) { + vmci_event_unsubscribe(vmci_transport_qp_resumed_sub_id); + vmci_transport_qp_resumed_sub_id = VMCI_INVALID_ID; + } + + vmci_register_vsock_callback(NULL); + vsock_core_unregister(&vmci_transport); +} +module_exit(vmci_transport_exit); + +MODULE_AUTHOR("VMware, Inc."); +MODULE_DESCRIPTION("VMCI transport for Virtual Sockets"); +MODULE_VERSION("1.0.5.0-k"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("vmware_vsock"); +MODULE_ALIAS_NETPROTO(PF_VSOCK); |