Initial signing support (#1345)

* Add CLI options

* Add manifest types

* Thread signature policy through to fetchers

* Thread signing section through from metadata

* Implement signing validation

* Clippy

* Attempt testing

* Yes and

* Why

* fmt

* Update crates/bin/src/args.rs

Co-authored-by: Jiahao XU <Jiahao_XU@outlook.com>

* Update crates/binstalk-fetchers/src/gh_crate_meta.rs

Co-authored-by: Jiahao XU <Jiahao_XU@outlook.com>

* Update crates/bin/src/args.rs

Co-authored-by: Jiahao XU <Jiahao_XU@outlook.com>

* Update crates/binstalk-fetchers/src/signing.rs

Co-authored-by: Jiahao XU <Jiahao_XU@outlook.com>

* Update crates/binstalk-fetchers/src/signing.rs

Co-authored-by: Jiahao XU <Jiahao_XU@outlook.com>

* Update crates/binstalk-fetchers/src/signing.rs

Co-authored-by: Jiahao XU <Jiahao_XU@outlook.com>

* Update crates/binstalk-fetchers/src/signing.rs

Co-authored-by: Jiahao XU <Jiahao_XU@outlook.com>

* fixes

* Finish feature

* Document

* Include all fields in the signing.file template

* Readme document

* Review fixes

* Fail on non-utf8 sig

* Thank goodness for tests

* Run test in ci

* Add rsign2 commands

* Log utf8 error

* Update e2e-tests/signing.sh

Co-authored-by: Jiahao XU <Jiahao_XU@outlook.com>

* Fix `e2e-tests/signing.sh` MacOS CI failure

Move the tls cert creation into `signing.sh` and sleep for 10s to wait
for https server to start.

Signed-off-by: Jiahao XU <Jiahao_XU@outlook.com>

* Refactor e2e-tests-signing files

 - Use a tempdir generated by `mktemp` for all certificates-related
   files
 - Put other checked-in files into `e2e-tests/signing`

Signed-off-by: Jiahao XU <Jiahao_XU@outlook.com>

* Fixed `e2e-tests-signing` connection err in MacOS CI

Wait for server to start up by trying to connect to it.

Signed-off-by: Jiahao XU <Jiahao_XU@outlook.com>

* Fix `e2e-tests-signing` passing `-subj` to `openssl` on Windows

Use single quote instead of double quote to avoid automatic expansion
from bash

Signed-off-by: Jiahao XU <Jiahao_XU@outlook.com>

* Fix `e2e-tests-signing` waiting for server to startup

Remove `timeout` since it is not supported on MacOS.

Signed-off-by: Jiahao XU <Jiahao_XU@outlook.com>

* Try to fix windows CI by setting `MSYS_NO_PATHCONV=1` on `openssl` cmds

Signed-off-by: Jiahao XU <Jiahao_XU@outlook.com>

* Fixed `e2e-tests-signing` on windows

By using double `//` for the value passed to option `-subj`

Signed-off-by: Jiahao XU <Jiahao_XU@outlook.com>

* Fixed infinite loop in `signing/wait-for-server` on Windows

Pass `--ssl-revoke-best-effort` to prevent schannel from checking ssl
revocation status.

Signed-off-by: Jiahao XU <Jiahao_XU@outlook.com>

* Add cap on retry attempt in `signing/wait-for-server.sh`

Signed-off-by: Jiahao XU <Jiahao_XU@outlook.com>

* Let `singing/server.py` print output to stderr

so that we can see the error message there.

Signed-off-by: Jiahao XU <Jiahao_XU@outlook.com>

* Fix running `signing/server.py` on MacOS CI

use `python3` since macos-latest still has python2 installed and
`python` is a symlink to `python2` there.

Signed-off-by: Jiahao XU <Jiahao_XU@outlook.com>

---------

Signed-off-by: Jiahao XU <Jiahao_XU@outlook.com>
Co-authored-by: Jiahao XU <Jiahao_XU@outlook.com>

Cargo.lock

@@ -314,12 +314,14 @@ dependencies = [
  "async-trait",
  "binstalk-downloader",
  "binstalk-types",
+ "bytes",
  "compact_str",
  "either",
  "itertools",
  "leon",
  "leon-macros",
  "miette",
+ "minisign-verify",
  "once_cell",
  "strum",
  "thiserror",
@@ -2511,6 +2513,12 @@ version = "0.3.17"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6877bb514081ee2a7ff5ef9de3281f14a4dd4bceac4c09388074a6b5df8a139a"
 
+[[package]]
+name = "minisign-verify"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "933dca44d65cdd53b355d0b73d380a2ff5da71f87f036053188bf1eab6a19881"
+
 [[package]]
 name = "miniz_oxide"
 version = "0.7.1"