adding pledge(2) and unveil(2) for openbsd, and fixing some typos and stuff

4 files changed, 49 insertions, 3 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 080fcbf..2b434ca 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -420,6 +420,15 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8b870d8c151b6f2fb93e84a13146138f05d02ed11c7e7c54f8826aaaf7c9f184"
 
 [[package]]
+name = "pledge"
+version = "0.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "252599417b7d9a43b7fdc63dd790b0848666a8910b2ebe1a25118309c3c981e5"
+dependencies = [
+ "libc",
+]
+
+[[package]]
 name = "postgres"
 version = "0.18.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -483,9 +492,11 @@ version = "0.1.0"
 dependencies = [
  "dotenv",
  "dumb_cgi",
+ "pledge",
  "postgres",
  "rand 0.8.5",
  "regex",
+ "unveil",
  "url",
 ]
 
@@ -757,6 +768,15 @@ dependencies = [
 ]
 
 [[package]]
+name = "unveil"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5e7fa867d559102001ec694165ed17d5f82e95213060a65f9c8b6280084bbfec"
+dependencies = [
+ "libc",
+]
+
+[[package]]
 name = "url"
 version = "2.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
diff --git a/Cargo.toml b/Cargo.toml
index 2132b6b..9f9ea0a 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -12,3 +12,5 @@ regex = "1"
 dotenv = "0.15"
 url = "2"
 rand = "0.8.5"
+unveil = "0.3"
+pledge = "0.4"
diff --git a/README.md b/README.md
index 73d6484..bc3662f 100644
--- a/README.md
+++ b/README.md
@@ -1,12 +1,13 @@
 # purl-rs
 A simple URL-shortener in Rust.
 
-I created this URL-shortener because it turned out that my previous one, `purl`,
-which was written i perl, was impractical to run in a `chroot` environment.
+I created this URL-shortener because it turned out that my previous one,
+[`purl`](https://git.dnns.no/purl/about/), which was written i perl, was
+impractical to run in a `chroot` environment.
 
 This new one, written in [Rust](https://www.rust-lang.org/), has far fewer
 dependencies to worry about in a `chroot` environment. It is written as a
-replacement for the old `purl`, and therefor uses
+replacement for the old `purl`, and uses
 [CGI](https://en.wikipedia.org/wiki/Common_Gateway_Interface).
 
 I use Nginx as my web-proxy, and run the cgi-binaries through
diff --git a/src/main.rs b/src/main.rs
index 638a9a0..ab5a1d4 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -16,14 +16,19 @@ use std::process::exit;
 use dotenv;
 use postgres::{Client, NoTls};
 use dumb_cgi::{Request, EmptyResponse, Query};
+use pledge::pledge_promises;
 use rand::{thread_rng, Rng, distributions::Alphanumeric};
 use regex::Regex;
+use unveil::unveil;
 use url::Url;
 
 
 // Do the dirty
 fn main() {
 
+    // Let's drop some privileges before we do anything else
+    drop_privs();
+
     // Get variables from dotenv, or use defaults
     let dburl:&str              = &dotenv::var("DATABASE_URL").unwrap_or("postgresql://localhost/purl-rs".to_string());
     let create_uri:&str         = &dotenv::var("CREATE_URI").unwrap_or("/create".to_string());
@@ -267,4 +272,22 @@ fn check_short(short:&str) -> bool {
 }
 
 
+//
+// Drop privileges
+//
+fn drop_privs() {
+    // Restrict what files we can access. See unveil(2)
+    unveil(".env", "r")
+        .or_else(unveil::Error::ignore_platform)
+        .unwrap();
+    unveil("", "")
+        .or_else(unveil::Error::ignore_platform)
+        .unwrap();
+
+    // Restrict what system calls we can access. See pledge(2)
+    pledge_promises![Stdio Rpath Inet Dns]
+        .or_else(pledge::Error::ignore_platform)
+        .unwrap();
+}
+
 // end of file