google / localtoast

Localtoast

Localtoast is a scanner for running security-related configuration checks such as CIS benchmarks in an easily configurable manner.

The scanner can either be used as a standalone binary to scan the local machine or as a library with a custom wrapper to perform scans on e.g. container images or remote hosts.

How to use

As a standalone binary:

1. Install the build deps
2. make
3. sudo ./localtoast --config=configs/example.textproto --result=scan-result.textproto

Build and use OS-specific configs:

1. make configs
2. sudo ./localtoast --config=configs/full/cos_97/instance_scanning.textproto --result=scan-result.textproto

Build and run Localtoast with SQL scanning capabilities:

1. make configs
2. make localtoast_sql
3. sudo localtoast_sql/localtoast_sql --config=configs/full/cassandra-cql/instance_scanning.textproto --result=scan-result.textproto --cassandra-database=localhost:9042

As a library:

1. Import github.com/google/localtoast/scannerlib and github.com/google/localtoast/scanapi into your Go project
2. Write a custom implementation for the scanapi.ScanAPI interface
3. Call scannerlib.Scanner{}.Scan() with the appropriate config and the implementation

See the scan config and result protos for details on the input+output format.

Defining custom checks

To add your own checks to a scan config,

1. Define the check in one of the definition files

• Example
• See the instruction proto for details on the instruction syntax

2. Add a reference to the check in the scan config you want to extend

• Example

3. Re-build the config file with make configs
4. Use the re-generated config file in your scans, e.g. sudo ./localtoast --config=configs/full/cos_97/instance_scanning.textproto --result=scan-result.textproto

Build dependencies

To build Localtoast, you'll need to have the following installed:

• go: Follow https://go.dev/doc/install
• protoc: Install the appropriate package, e.g. apt install protobuf-compiler
• protoc-gen-go: Run go install google.golang.org/protobuf/cmd/protoc-gen-go

Contributing

Read how to contribute to Localtoast.

License

Localtoast is released under the Apache 2.0 license.

Copyright 2021 Google Inc.

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.

Disclaimers

Localtoast is not an official Google product.

localtoast's Issues

Consider adding `/scannerlib/proto` as part of source control

Currently, in a clean repo state, the Go module has unknown dependencies that exist only after a build has happened (or the build-proto.sh script is run):

❯ go mod tidy
go: finding module for package github.com/google/localtoast/scannerlib/proto/severity_go_proto
go: finding module for package github.com/google/localtoast/scannerlib/proto/compliance_go_proto
go: finding module for package github.com/google/localtoast/scannerlib/proto/scan_instructions_go_proto
go: finding module for package github.com/google/localtoast/scannerlib/proto/api_go_proto
github.com/google/localtoast imports
        github.com/google/localtoast/scannerlib/proto/api_go_proto: no matching versions for query "latest"
github.com/google/localtoast/configs/genfullconfig/genfullconfiglib imports
        github.com/google/localtoast/scannerlib/proto/compliance_go_proto: no matching versions for query "latest"
github.com/google/localtoast/configs/genfullconfig/genfullconfiglib imports
        github.com/google/localtoast/scannerlib/proto/scan_instructions_go_proto: no matching versions for query "latest"
github.com/google/localtoast/configs tested by
        github.com/google/localtoast/configs.test imports
        github.com/google/localtoast/scannerlib/proto/severity_go_proto: no matching versions for query "latest"

❯ make
./build_protos.sh
--2022-09-06 17:37:44--  https://github.com/grafeas/grafeas/archive/0163b5bb2ff5afbf059ddf472fb4d128faae85e3.tar.gz
Resolving github.com (github.com)... 192.30.255.112
Connecting to github.com (github.com)|192.30.255.112|:443... connected.
HTTP request sent, awaiting response... 302 Found
Location: https://codeload.github.com/grafeas/grafeas/tar.gz/0163b5bb2ff5afbf059ddf472fb4d128faae85e3 [following]
--2022-09-06 17:37:45--  https://codeload.github.com/grafeas/grafeas/tar.gz/0163b5bb2ff5afbf059ddf472fb4d128faae85e3
Resolving codeload.github.com (codeload.github.com)... 192.30.255.120
Connecting to codeload.github.com (codeload.github.com)|192.30.255.120|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: unspecified [application/x-gzip]
Saving to: ‘0163b5bb2ff5afbf059ddf472fb4d128faae85e3.tar.gz’

0163b5bb2ff5afbf059ddf472fb4d128faae85e3.tar.gz                        [         <=>                                                                                                                                                  ]   9.24M  5.24MB/s    in 1.8s

2022-09-06 17:37:47 (5.24 MB/s) - ‘0163b5bb2ff5afbf059ddf472fb4d128faae85e3.tar.gz’ saved [9694009]

go build localtoast.go

After the fact, go mod is able to resolve the dependencies correctly. Looks like it's primarily the dependency on github.com/grafeas/grafeas. This creates an interlinking of code sources in the build tree that do not exist as part of the source control.

Would it be possible to add github.com/grafeas/grafeas as part of the source control? Possible as a git submodule or maybe a static code dependency?

This makes building from a airgapped / non-networked environment much more challenging since the entire source code is not in the base repo.

Need documentation on `protoc` buildtime dependency

On attempting to build the localtoast binary per the README.md instructions from the v1.1.4.3 code tarball:

❯ make
go install google.golang.org/protobuf/cmd/protoc-gen-go
protoc -I=. --go_out=. scannerlib/proto/*.proto
/bin/sh: line 1: protoc: command not found
make: *** [Makefile:5: localtoast] Error 127

Seems that it's expected to build the gRPC protos before a build is executed through the build_protos.sh script.

It'd be nice if this was documented or if there was a different make target provided that didn't require the protos to be created before the binary is built.

error scanning rocky linux instance

Running the following:
sudo ./localtoast --config=instance_scanning.textproto --result=scan-result.textproto

On one of my Rocky Linux machines I got the following error, consistently:

[file check on files_in_dir:{dir_path:"/proc" recursive:true skip_symlinks:true filename_regex:"current" opt_out_path_regexes:"/proc/[a-z].*"}]: readdirent /proc/921/task/921/net: invalid argument

OS version

cat /etc/os-release
NAME="Rocky Linux"
VERSION="8.5 (Green Obsidian)"
ID="rocky"
ID_LIKE="rhel centos fedora"
VERSION_ID="8.5"
PLATFORM_ID="platform:el8"
PRETTY_NAME="Rocky Linux 8.5 (Green Obsidian)"
ANSI_COLOR="0;32"
CPE_NAME="cpe:/o:rocky:rocky:8:GA"
HOME_URL="https://rockylinux.org/"
BUG_REPORT_URL="https://bugs.rockylinux.org/"
ROCKY_SUPPORT_PRODUCT="Rocky Linux"
ROCKY_SUPPORT_PRODUCT_VERSION="8"