Implement stubs for mq_open(2) and mq_unlink(2).

Support mq_open and mq_unlink, and enable syscall tests.

Updates #136

1 files changed, 98 insertions, 0 deletions

diff --git a/pkg/sentry/syscalls/linux/vfs2/mq.go b/pkg/sentry/syscalls/linux/vfs2/mq.go
new file mode 100644
index 000000000..d5d81c6e2
--- /dev/null
+++ b/pkg/sentry/syscalls/linux/vfs2/mq.go
@@ -0,0 +1,98 @@
+// Copyright 2021 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package vfs2
+
+import (
+	"gvisor.dev/gvisor/pkg/abi/linux"
+	"gvisor.dev/gvisor/pkg/sentry/arch"
+	"gvisor.dev/gvisor/pkg/sentry/kernel"
+	"gvisor.dev/gvisor/pkg/sentry/kernel/mq"
+)
+
+// MqOpen implements mq_open(2).
+func MqOpen(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+	nameAddr := args[0].Pointer()
+	flag := args[1].Int()
+	mode := args[2].ModeT()
+	attrAddr := args[3].Pointer()
+
+	name, err := t.CopyInString(nameAddr, mq.MaxName)
+	if err != nil {
+		return 0, nil, err
+	}
+
+	rOnly := flag&linux.O_RDONLY == linux.O_RDONLY
+	wOnly := flag&linux.O_WRONLY == linux.O_WRONLY
+	readWrite := flag&linux.O_RDWR == linux.O_RDWR
+
+	create := flag&linux.O_CREAT == linux.O_CREAT
+	exclusive := flag&linux.O_EXCL == linux.O_EXCL
+	block := flag&linux.O_NONBLOCK != linux.O_NONBLOCK
+
+	var attr linux.MqAttr
+	var attrPtr *linux.MqAttr
+	if attrAddr != 0 {
+		if _, err := attr.CopyIn(t, attrAddr); err != nil {
+			return 0, nil, err
+		}
+		attrPtr = &attr
+	}
+
+	opts := openOpts(name, rOnly, wOnly, readWrite, create, exclusive, block)
+
+	r := t.IPCNamespace().PosixQueues()
+	queue, err := r.FindOrCreate(t, opts, linux.FileMode(mode), attrPtr)
+	if err != nil {
+		return 0, nil, err
+	}
+
+	fd, err := t.NewFDFromVFS2(0, queue, kernel.FDFlags{
+		CloseOnExec: flag&linux.O_CLOEXEC != 0,
+	})
+	if err != nil {
+		return 0, nil, err
+	}
+	return uintptr(fd), nil, nil
+}
+
+// MqUnlink implements mq_unlink(2).
+func MqUnlink(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+	nameAddr := args[0].Pointer()
+	name, err := t.CopyInString(nameAddr, mq.MaxName)
+	if err != nil {
+		return 0, nil, err
+	}
+	return 0, nil, t.IPCNamespace().PosixQueues().Remove(t, name)
+}
+
+func openOpts(name string, rOnly, wOnly, readWrite, create, exclusive, block bool) mq.OpenOpts {
+	var access mq.AccessType
+	switch {
+	case readWrite:
+		access = mq.ReadWrite
+	case wOnly:
+		access = mq.WriteOnly
+	case rOnly:
+		access = mq.ReadOnly
+	}
+
+	return mq.OpenOpts{
+		Name:      name,
+		Access:    access,
+		Create:    create,
+		Exclusive: exclusive,
+		Block:     block,
+	}
+}