Fix unaligned read by switching from unmaintained users crate (#26)

* Fix unaligned read by switching from unmaintained users crate

* Bump proc-macro2 to to fix "unknown feature `proc_macro_span_shrink`"

Cargo.lock

@@ -970,9 +970,9 @@ dependencies = [
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.51"
+version = "1.0.66"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5d727cae5b39d21da60fa540906919ad737832fe0b1c165da3a34d6548c849d6"
+checksum = "18fb31db3f9bddb2ea821cde30a9f70117e3f119938b5ee630b7403aa6e2ead9"
 dependencies = [
  "unicode-ident",
 ]
@@ -1351,7 +1351,7 @@ dependencies = [
  "sentry-anyhow",
  "smoltcp",
  "system-configuration",
- "users",
+ "uzers",
  "vmnet",
 ]
 
@@ -1634,16 +1634,6 @@ dependencies = [
  "serde",
 ]
 
-[[package]]
-name = "users"
-version = "0.11.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "24cc0f6d6f267b73e5a2cadf007ba8f9bc39c6a6f9666f8cf25ea809a153b032"
-dependencies = [
- "libc",
- "log",
-]
-
 [[package]]
 name = "uuid"
 version = "1.3.0"
@@ -1654,6 +1644,16 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "uzers"
+version = "0.11.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "76d283dc7e8c901e79e32d077866eaf599156cbf427fffa8289aecc52c5c3f63"
+dependencies = [
+ "libc",
+ "log",
+]
+
 [[package]]
 name = "vcpkg"
 version = "0.2.15"

Cargo.toml

@@ -22,7 +22,7 @@ mac_address = "1.1.3"
 privdrop = "0.5.2"
 anyhow = { version = "1.0.66", features = ["backtrace"] }
 ip_network = "0.4.1"
-users = "0.11.0"
+uzers = "0.11.3"
 system-configuration = "0.5.0"
 num_enum = "0.5.7"
 sentry = { version = "0.29.1", features = ["debug-images"] }

README.md

@@ -1,13 +1,14 @@
 # Softnet
 
 Softnet is a software networking for [Tart](https://github.com/cirruslabs/tart) which provides better network isolation and alleviates DHCP shortage on production systems.
+Please check out [this blog post](https://cirrus-ci.org/blog/2022/07/07/isolating-network-between-tarts-macos-virtual-machines/) for backstory.
 
 ## Working model
 
 Softnet solves two problems:
 
 1. VM network isolation
-  * [`VZNATNetworkDeviceAttachment`](https://developer.apple.com/documentation/virtualization/vznatnetworkdeviceattachment) (the default networking in Tart) enables [vmnet's bridge isolation](https://developer.apple.com/documentation/vmnet/vmnet_enable_isolation_key) by default and prevents cross-VM traffic, however it's still possible for any VM to spoof the host's ARP-table and capture other VMs traffic, for example
+  * [`VZNATNetworkDeviceAttachment`](https://developer.apple.com/documentation/virtualization/vznatnetworkdeviceattachment) (the default networking in Tart) enables [vmnet's bridge isolation](https://developer.apple.com/documentation/vmnet/vmnet_enable_isolation_key) by default and prevents cross-VM traffic, however it's still possible for any VM to spoof the host's ARP-table and capture other VMs traffic
 2. DHCP exhaustion
   * macOS built-in DHCP-server allocates a `/24` subnet with 86400 seconds lease time by default, which only allows for ~253 VMs a day (or 1 VM every ~6 minutes) to be spawned without causing a denial-of-service, which is pretty limiting for CI services like Cirrus CI
 
@@ -30,4 +31,4 @@ For proper functioning, Softnet binary requires two things:
 
 ## Running
 
-Softnet is started and managed automatically by Tart if `--with-softnet` flag is present when calling `tart run`.
+Softnet is started and managed automatically by Tart if `--net-softnet` flag is provided when calling `tart run`.

src/main.rs

@@ -15,7 +15,7 @@ use system_configuration::core_foundation::number::CFNumber;
 use system_configuration::core_foundation::string::CFString;
 use system_configuration::preferences::SCPreferences;
 use system_configuration::sys::preferences::{SCPreferencesCommitChanges, SCPreferencesSetValue};
-use users::{get_current_groupname, get_current_username, get_effective_uid};
+use uzers::{get_current_groupname, get_current_username, get_effective_uid};
 
 #[derive(Parser, Debug)]
 struct Args {