UEFI EDK II, TPM minting, QEMU launcher and basic DHCP support
Test Plan:
You still need a recent version of QEMU and swtpm installed (these are not yet integrated)
Run `make launch` and have fun with a running Smalltown instance :)
X-Origin-Diff: phab/D159
GitOrigin-RevId: c7245bfbabebf92507445525bee009a71d19caea
diff --git a/internal/storage/find.go b/internal/storage/find.go
new file mode 100644
index 0000000..72d3f6a
--- /dev/null
+++ b/internal/storage/find.go
@@ -0,0 +1,96 @@
+// Copyright 2020 The Monogon Project Authors.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+// 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 storage
+
+import (
+ "fmt"
+ "io/ioutil"
+ "os"
+ "path/filepath"
+ "smalltown/pkg/sysfs"
+ "strconv"
+
+ "github.com/rekby/gpt"
+ "golang.org/x/sys/unix"
+)
+
+// EFIPartitionType is the standardized partition type value for the EFI ESP partition. The human readable GUID is C12A7328-F81F-11D2-BA4B-00A0C93EC93B.
+var EFIPartitionType = gpt.PartType{0x28, 0x73, 0x2a, 0xc1, 0x1f, 0xf8, 0xd2, 0x11, 0xba, 0x4b, 0x00, 0xa0, 0xc9, 0x3e, 0xc9, 0x3b}
+
+// SmalltownDataPartitionType is the partition type value for a Smalltown data partition. The human-readable GUID is 9eeec464-6885-414a-b278-4305c51f7966.
+var SmalltownDataPartitionType = gpt.PartType{0x64, 0xc4, 0xee, 0x9e, 0x85, 0x68, 0x4a, 0x41, 0xb2, 0x78, 0x43, 0x05, 0xc5, 0x1f, 0x79, 0x66}
+
+var ESPDevicePath = "/dev/esp"
+var SmalltownDataCryptPath = "/dev/data-crypt"
+
+// FindPartitions looks for the ESP and the Smalltown data partition and maps them to ESPDevicePath and
+// SmalltownDataCryptPath respectively. This doesn't fail if it doesn't find the partitions, only if
+// something goes catastrophically wrong.
+func FindPartitions() error {
+ blockdevNames, err := ioutil.ReadDir("/sys/class/block")
+ if err != nil {
+ return fmt.Errorf("failed to read sysfs block class: %w", err)
+ }
+ for _, blockdevName := range blockdevNames {
+ ueventData, err := sysfs.ReadUevents(filepath.Join("/sys/class/block", blockdevName.Name(), "uevent"))
+ if err != nil {
+ return fmt.Errorf("failed to read uevent for block device %v: %w", blockdevName.Name(), err)
+ }
+ if ueventData["DEVTYPE"] == "disk" {
+ majorDev, err := strconv.Atoi(ueventData["MAJOR"])
+ if err != nil {
+ return fmt.Errorf("failed to convert uevent: %w", err)
+ }
+ minorDev, err := strconv.Atoi(ueventData["MINOR"])
+ if err != nil {
+ return fmt.Errorf("failed to convert uevent: %w", err)
+ }
+ devNodeName := fmt.Sprintf("/dev/%v", ueventData["DEVNAME"])
+ if err := unix.Mknod(devNodeName, 0600|unix.S_IFBLK, int(unix.Mkdev(uint32(majorDev), uint32(minorDev)))); err != nil {
+ return fmt.Errorf("failed to create block device node: %w", err)
+ }
+ blkdev, err := os.Open(devNodeName)
+ if err != nil {
+ return fmt.Errorf("failed to open block device %v: %w", devNodeName, err)
+ }
+ defer blkdev.Close()
+ blockSize, err := unix.IoctlGetUint32(int(blkdev.Fd()), unix.BLKSSZGET)
+ if err != nil {
+ continue // This is not a regular block device
+ }
+ blkdev.Seek(int64(blockSize), 0)
+ table, err := gpt.ReadTable(blkdev, uint64(blockSize))
+ if err != nil {
+ // Probably just not a GPT-partitioned disk
+ continue
+ }
+ for partNumber, part := range table.Partitions {
+ if part.Type == EFIPartitionType {
+ if err := unix.Mknod(ESPDevicePath, 0600|unix.S_IFBLK, int(unix.Mkdev(uint32(majorDev), uint32(partNumber+1)))); err != nil {
+ return fmt.Errorf("failed to create device node for ESP partition: %w", err)
+ }
+ }
+ if part.Type == SmalltownDataPartitionType {
+ if err := unix.Mknod(SmalltownDataCryptPath, 0600|unix.S_IFBLK, int(unix.Mkdev(uint32(majorDev), uint32(partNumber+1)))); err != nil {
+ return fmt.Errorf("failed to create device node for Smalltown encrypted data partition: %w", err)
+ }
+ }
+ }
+ }
+ }
+ return nil
+}