Implement secure password generation (#8)

crates/storage/src/write.rs

@@ -248,6 +248,48 @@ impl<'a> VaultWriter<'a> {
         })
     }
 
+    #[allow(clippy::too_many_arguments)]
+    pub fn store_generated(
+        &self,
+        path: &EntryPath,
+        contents: SecretBytes,
+        force: bool,
+        overwrite: OverwriteDecision,
+        signing: Option<&SigningPolicy>,
+        committer: &mut impl EntryCommitter,
+    ) -> Result<WriteOutcome, WriteError> {
+        let original = match self.repository.read_entry(path) {
+            Ok(original) => Some(original),
+            Err(RepositoryError::NotFound { .. }) => None,
+            Err(error) => return Err(error.into()),
+        };
+        if original.is_some() && !force && overwrite == OverwriteDecision::Decline {
+            return Err(WriteError::Cancelled);
+        }
+        let recipients = RecipientPolicyManager::new(self.repository, self.keys)
+            .resolve_for_entry(path, signing)?;
+        let ciphertext = self.keys.encrypt(contents, recipients.recipients())?;
+        self.repository.write_entry(path, &ciphertext)?;
+        let change = EntryCommit {
+            path: path.clone(),
+            action: EntryAction::Insert,
+            message: format!("Add generated password for {path}."),
+        };
+        if let Err(error) = committer.commit(&change) {
+            if let Err(rollback) = self.restore(path, original.as_ref()) {
+                return Err(WriteError::RollbackFailed {
+                    operation: error,
+                    rollback,
+                });
+            }
+            return Err(WriteError::Commit(error));
+        }
+        Ok(WriteOutcome {
+            path: path.clone(),
+            action: EntryAction::Insert,
+        })
+    }
+
     #[allow(clippy::too_many_arguments)]
     pub fn finish_edit(
         &self,