extract config and encryption modules

src/encryption.rs

@@ -0,0 +1,45 @@
+use std::path::PathBuf;
+
+use anyhow::{Result, bail};
+
+use crate::cmd::cryptsetup;
+use crate::config;
+
+pub fn decrypt_backup(pools: &config::BackupPools) -> Result<(String, String)> {
+    let mut pathbuf = PathBuf::new();
+    let mut found = false;
+
+    let mut the_name = String::new();
+    let mut the_crypt_device = String::new();
+
+    for (device, name) in [&pools.backup1, &pools.backup2]
+        .iter()
+        .zip(["backup1", "backup2"])
+    {
+        pathbuf.push("/dev/disk/by-uuid/");
+        pathbuf.push(device);
+
+        if pathbuf.exists() {
+            found = true;
+            the_name = name.to_string();
+
+            the_crypt_device.push_str("crypt-");
+            the_crypt_device.push_str(name); // content is then e.g. "crypt-backup1"
+
+            println!("found backup disk {name}, will decrypt to {the_crypt_device}");
+            break;
+        }
+    }
+
+    if found {
+        cryptsetup::open(&pathbuf, &the_crypt_device)?;
+        Ok((the_name, the_crypt_device))
+    } else {
+        bail!("no backup disk found")
+    }
+}
+
+pub fn encrypt_backup(crypt_device: String) -> Result<()> {
+    println!("encrypting {crypt_device}");
+    cryptsetup::close(&crypt_device)
+}