[pbs-devel] [PATCH proxmox 2/4] ldap: add check_connection function

[Stefan Sterz <s.sterz@proxmox.com>]

this function checks if a given connection could work. it uses the
current config to connect to an ldap directory and perform a search
with the provided base_dn. this enables us to verify a connection
before storing it in a more meaningful way than with a regex.

Signed-off-by: Stefan Sterz <s.sterz@proxmox.com>
---
 proxmox-ldap/src/lib.rs | 50 ++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 49 insertions(+), 1 deletion(-)

diff --git a/proxmox-ldap/src/lib.rs b/proxmox-ldap/src/lib.rs
index cdc4c9d..c47870d 100644
--- a/proxmox-ldap/src/lib.rs
+++ b/proxmox-ldap/src/lib.rs
@@ -6,7 +6,7 @@ use std::{
     time::Duration,
 };
 
-use anyhow::{bail, format_err, Error};
+use anyhow::{bail, format_err, Context, Error};
 use ldap3::adapters::{Adapter, EntriesOnly, PagedResults};
 use ldap3::{Ldap, LdapConnAsync, LdapConnSettings, LdapResult, Scope, SearchEntry};
 use native_tls::{Certificate, TlsConnector, TlsConnectorBuilder};
@@ -158,6 +158,54 @@ impl Connection {
         Ok(results)
     }
 
+    /// Helper to check if a connection with the current configuration is possible.
+    ///
+    /// This performs a search with the current configuration. If the search succeeds `Ok(()) is
+    /// returned, otherwise an `Error` is returned.
+    pub async fn check_connection(&self) -> Result<(), Error> {
+        let mut ldap = self.create_connection().await?;
+
+        if let Some(bind_dn) = self.config.bind_dn.as_deref() {
+            let password = self
+                .config
+                .bind_password
+                .as_deref()
+                .ok_or_else(|| format_err!("Missing bind password for {bind_dn}"))?;
+
+            let _: LdapResult = ldap
+                .simple_bind(bind_dn, password)
+                .await?
+                .success()
+                .context("LDAP bind failed, bind_dn or password could be incorrect")?;
+
+            let (_, _) = ldap
+                .search(
+                    &self.config.base_dn,
+                    Scope::Subtree,
+                    "(objectClass=*)",
+                    vec!["*"],
+                )
+                .await?
+                .success()
+                .context("Could not search LDAP realm, base_dn could be incorrect")?;
+
+            let _: Result<(), _> = ldap.unbind().await; // ignore errors, search succeeded already
+        } else {
+            let (_, _) = ldap
+                .search(
+                    &self.config.base_dn,
+                    Scope::Subtree,
+                    "(objectClass=*)",
+                    vec!["*"],
+                )
+                .await?
+                .success()
+                .context("Could not search LDAP realm, base_dn could be incorrect")?;
+        }
+
+        Ok(())
+    }
+
     /// Retrive port from LDAP configuration, otherwise use the correct default
     fn port_from_config(&self) -> u16 {
         self.config.port.unwrap_or_else(|| {
-- 
2.39.2