[PATCH proxmox-ve-rs 8/9] ve-config: fabrics: wireguard add validation for wireguard config

[Stefan Hanreich <s.hanreich@proxmox.com>]

Implement validation for the invariants of the wireguard
configuration:

* All interfaces referenced in peer definitions must exist
* Listen ports cannot be duplicated
* Interface names must be unique on a node

Signed-off-by: Stefan Hanreich <s.hanreich@proxmox.com>
---
 proxmox-ve-config/Cargo.toml                  |   1 +
 proxmox-ve-config/src/sdn/fabric/mod.rs       | 161 ++++++++++++++++--
 .../src/sdn/fabric/section_config/node.rs     |   2 +-
 .../section_config/protocol/wireguard.rs      |  63 ++++++-
 4 files changed, 210 insertions(+), 17 deletions(-)

diff --git a/proxmox-ve-config/Cargo.toml b/proxmox-ve-config/Cargo.toml
index fdcb331..bb1a057 100644
--- a/proxmox-ve-config/Cargo.toml
+++ b/proxmox-ve-config/Cargo.toml
@@ -33,3 +33,4 @@ frr = ["dep:proxmox-frr"]
 
 [dev-dependencies]
 insta = "1.21"
+pretty_assertions = "1.4.0"
diff --git a/proxmox-ve-config/src/sdn/fabric/mod.rs b/proxmox-ve-config/src/sdn/fabric/mod.rs
index 53ce87f..7d1a2b9 100644
--- a/proxmox-ve-config/src/sdn/fabric/mod.rs
+++ b/proxmox-ve-config/src/sdn/fabric/mod.rs
@@ -31,7 +31,7 @@ use crate::sdn::fabric::section_config::protocol::ospf::{
 };
 use crate::sdn::fabric::section_config::protocol::wireguard::{
     WireGuardDeletableProperties, WireGuardNode, WireGuardNodeDeletableProperties,
-    WireGuardNodeUpdater, WireGuardPropertiesUpdater,
+    WireGuardNodePeer, WireGuardNodeUpdater, WireGuardPropertiesUpdater,
 };
 use crate::sdn::fabric::section_config::{FabricOrNode, Section};
 
@@ -73,6 +73,10 @@ pub enum FabricConfigError {
     OverlappingIp4Prefix(String, String, String, String),
     #[error("IPv6 prefix {0} in fabric '{1}' overlaps with IPv6 prefix {2} in fabric '{3}'")]
     OverlappingIp6Prefix(String, String, String, String),
+    #[error("peer configuration references non-existing interface")]
+    InvalidInterfaceReference,
+    #[error("WireGuard interface listen port duplicated in node configuration: {0}")]
+    DuplicatePort(String),
 }
 
 /// An entry in a [`FabricConfig`].
@@ -500,7 +504,49 @@ impl Validatable for FabricEntry {
         let mut ips = HashSet::new();
         let mut ip6s = HashSet::new();
 
+        if let FabricEntry::WireGuard(entry) = self {
+            // check if all interfaces referenced by the peer definitions exist inside the
+            // fabric
+            let mut all_interfaces = HashSet::new();
+            let mut internal_peers = HashSet::new();
+
+            for node_id in entry.nodes.keys() {
+                let node_section = entry.node_section(node_id)?;
+
+                if let WireGuardNode::Internal(node) = node_section.properties() {
+                    all_interfaces.extend(
+                        node.interfaces()
+                            .map(|interface| (&node_section.id.node_id, &interface.name)),
+                    );
+
+                    internal_peers.extend(node.peers().filter_map(|peer| {
+                        if let WireGuardNodePeer::Internal(peer) = peer {
+                            return Some((&peer.node, &peer.node_iface));
+                        }
+
+                        None
+                    }));
+                }
+            }
+
+            if !(all_interfaces.is_superset(&internal_peers)) {
+                return Err(FabricConfigError::InvalidInterfaceReference);
+            }
+        }
+
         for (_id, node) in self.nodes() {
+            node.validate()?;
+
+            // Node IPs need to be unique inside a fabric
+            if !node.ip().map(|ip| ips.insert(ip)).unwrap_or(true) {
+                return Err(FabricConfigError::DuplicateNodeIp(fabric.id().to_string()));
+            }
+
+            // Node IPs need to be unique inside a fabric
+            if !node.ip6().map(|ip| ip6s.insert(ip)).unwrap_or(true) {
+                return Err(FabricConfigError::DuplicateNodeIp(fabric.id().to_string()));
+            }
+
             // Check IPv4 prefix and ip
             match (fabric.ip_prefix(), node.ip()) {
                 (None, Some(ip)) => {
@@ -554,18 +600,6 @@ impl Validatable for FabricEntry {
                 }
                 _ => {}
             }
-
-            // Node IPs need to be unique inside a fabric
-            if !node.ip().map(|ip| ips.insert(ip)).unwrap_or(true) {
-                return Err(FabricConfigError::DuplicateNodeIp(fabric.id().to_string()));
-            }
-
-            // Node IPs need to be unique inside a fabric
-            if !node.ip6().map(|ip| ip6s.insert(ip)).unwrap_or(true) {
-                return Err(FabricConfigError::DuplicateNodeIp(fabric.id().to_string()));
-            }
-
-            node.validate()?;
         }
 
         fabric.validate()
@@ -634,6 +668,7 @@ impl Validatable for FabricConfig {
         }
 
         // validate that each (node, interface) combination exists only once across all fabrics
+        // additionally, for wireguard check the listen ports of the interfaces as well
         for entry in self.fabrics.values() {
             if let FabricEntry::Ospf(entry) = entry {
                 if !ospf_area.insert(
@@ -662,8 +697,14 @@ impl Validatable for FabricConfig {
                             return Err(FabricConfigError::DuplicateInterface);
                         }
                     }
-                    Node::WireGuard(_node_section) => {
-                        return Ok(());
+                    Node::WireGuard(node_section) => {
+                        if let WireGuardNode::Internal(internal_node) = node_section.properties() {
+                            if !internal_node.interfaces().all(|interface| {
+                                node_interfaces.insert((node_id, interface.name.as_str()))
+                            }) {
+                                return Err(FabricConfigError::DuplicateInterface);
+                            }
+                        }
                     }
                 }
             }
@@ -952,3 +993,93 @@ impl Valid<FabricConfig> {
         Section::write_section_config("fabrics.cfg", &self.into_section_config())
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use crate::sdn::fabric::FabricConfig;
+    use proxmox_section_config::typed::ApiSectionDataEntry;
+
+    use super::*;
+
+    #[test]
+    fn test_wireguard_validation_duplicate_interface() -> Result<(), anyhow::Error> {
+        let section_config = r#"
+wireguard_fabric: wireg
+
+wireguard_node: wireg_internal
+    role internal
+    endpoint 192.0.2.1:123
+    public_key Kay64UG8yvCyLhqU000LxzYeUm0L/hLIl5S8kyKWbdc=
+    interfaces name=wg0,listen_port=51111,public_key=Kay64UG8yvCyLhqU000LxzYeUm0L/hLIl5S8kyKWbdc=
+    interfaces name=wg0,listen_port=51112,public_key=Kay64UG8yvCyLhqU000LxzYeUm0L/hLIl5S8kyKWbdc=
+"#;
+        let parsed_config = Section::parse_section_config("fabrics.cfg", section_config)?;
+        FabricConfig::from_section_config(parsed_config)
+            .expect_err("duplicate interface name on node");
+
+        Ok(())
+    }
+
+    #[test]
+    fn test_wireguard_validation_duplicate_listen_port() -> Result<(), anyhow::Error> {
+        let section_config = r#"
+wireguard_fabric: wireg
+
+wireguard_node: wireg_internal
+    role internal
+    endpoint 192.0.2.1:123
+    public_key Kay64UG8yvCyLhqU000LxzYeUm0L/hLIl5S8kyKWbdc=
+    interfaces name=wg0,listen_port=51111,public_key=Kay64UG8yvCyLhqU000LxzYeUm0L/hLIl5S8kyKWbdc=
+    interfaces name=wg1,listen_port=51111,public_key=Kay64UG8yvCyLhqU000LxzYeUm0L/hLIl5S8kyKWbdc=
+"#;
+        let parsed_config = Section::parse_section_config("fabrics.cfg", section_config)?;
+        FabricConfig::from_section_config(parsed_config)
+            .expect_err("duplicate listen_port on node");
+
+        Ok(())
+    }
+
+    #[test]
+    fn test_wireguard_validation_node_interface_does_not_exist() -> Result<(), anyhow::Error> {
+        let section_config = r#"
+wireguard_fabric: wireg
+
+wireguard_node: wireg_internal
+    role internal
+    endpoint 192.0.2.1:123
+    public_key Kay64UG8yvCyLhqU000LxzYeUm0L/hLIl5S8kyKWbdc=
+    interfaces name=wg0,listen_port=51111,public_key=Kay64UG8yvCyLhqU000LxzYeUm0L/hLIl5S8kyKWbdc=
+    peers type=internal,node=invalid,node_iface=invalid,iface=wg0
+"#;
+        let parsed_config = Section::parse_section_config("fabrics.cfg", section_config)?;
+        FabricConfig::from_section_config(parsed_config)
+            .expect_err("interface referenced in peer definition does not exist");
+
+        Ok(())
+    }
+
+    #[test]
+    fn test_wireguard_validation_local_interface_does_not_exist() -> Result<(), anyhow::Error> {
+        let section_config = r#"
+wireguard_fabric: wireg
+
+wireguard_node: wireg_internal
+    role internal
+    endpoint 192.0.2.1:123
+    public_key Kay64UG8yvCyLhqU000LxzYeUm0L/hLIl5S8kyKWbdc=
+    interfaces name=wg0,listen_port=51111,public_key=Kay64UG8yvCyLhqU000LxzYeUm0L/hLIl5S8kyKWbdc=
+
+wireguard_node: wireg_internal2
+    role internal
+    endpoint 192.0.2.2:123
+    public_key Kay64UG8yvCyLhqU000LxzYeUm0L/hLIl5S8kyKWbdc=
+    interfaces name=wg0,listen_port=51111,public_key=Kay64UG8yvCyLhqU000LxzYeUm0L/hLIl5S8kyKWbdc=
+    peers type=internal,node=internal,node_iface=wg0,iface=wg1
+"#;
+        let parsed_config = Section::parse_section_config("fabrics.cfg", section_config)?;
+        FabricConfig::from_section_config(parsed_config)
+            .expect_err("local interface in peer definition does not exist");
+
+        Ok(())
+    }
+}
diff --git a/proxmox-ve-config/src/sdn/fabric/section_config/node.rs b/proxmox-ve-config/src/sdn/fabric/section_config/node.rs
index 77ce15f..c7b26f4 100644
--- a/proxmox-ve-config/src/sdn/fabric/section_config/node.rs
+++ b/proxmox-ve-config/src/sdn/fabric/section_config/node.rs
@@ -239,7 +239,7 @@ impl Validatable for Node {
         match self {
             Node::Openfabric(node_section) => node_section.validate(),
             Node::Ospf(node_section) => node_section.validate(),
-            Node::WireGuard(_node_section) => Ok(()),
+            Node::WireGuard(node_section) => node_section.validate(),
         }
     }
 }
diff --git a/proxmox-ve-config/src/sdn/fabric/section_config/protocol/wireguard.rs b/proxmox-ve-config/src/sdn/fabric/section_config/protocol/wireguard.rs
index 3765b89..3acd856 100644
--- a/proxmox-ve-config/src/sdn/fabric/section_config/protocol/wireguard.rs
+++ b/proxmox-ve-config/src/sdn/fabric/section_config/protocol/wireguard.rs
@@ -28,6 +28,7 @@
 //! definition can be overridden in the peer definition, if e.g. a different endpoint is required
 //! for connecting to a node.
 
+use std::collections::HashSet;
 use std::ops::{Deref, DerefMut};
 
 use anyhow::Result;
@@ -44,7 +45,10 @@ use proxmox_sdn_types::wireguard::PersistentKeepalive;
 use proxmox_wireguard::PublicKey;
 use serde::{Deserialize, Serialize};
 
-use crate::sdn::fabric::section_config::node::NodeId;
+use crate::common::valid::Validatable;
+use crate::sdn::fabric::section_config::fabric::FabricSection;
+use crate::sdn::fabric::section_config::node::{NodeId, NodeSection};
+use crate::sdn::fabric::FabricConfigError;
 
 pub const WIREGUARD_INTERFACE_NAME_REGEX_STR: &str = "[a-zA-Z0-9][a-zA-Z0-9-]{0,6}[a-zA-Z0-9]?";
 
@@ -79,6 +83,14 @@ pub struct WireGuardProperties {
     pub(crate) persistent_keepalive: Option<PersistentKeepalive>,
 }
 
+impl Validatable for FabricSection<WireGuardProperties> {
+    type Error = FabricConfigError;
+
+    fn validate(&self) -> Result<(), Self::Error> {
+        Ok(())
+    }
+}
+
 #[derive(Clone, Debug, Serialize, Deserialize)]
 #[serde(rename_all = "snake_case")]
 pub enum WireGuardDeletableProperties {
@@ -159,6 +171,18 @@ impl ApiType for WireGuardNode {
     .schema();
 }
 
+impl Validatable for NodeSection<WireGuardNode> {
+    type Error = FabricConfigError;
+
+    fn validate(&self) -> Result<(), Self::Error> {
+        if let WireGuardNode::Internal(node) = self.properties() {
+            return node.validate();
+        }
+
+        Ok(())
+    }
+}
+
 #[derive(Debug, Clone, Serialize, Deserialize, Hash)]
 #[serde(rename_all = "snake_case", tag = "role")]
 pub enum WireGuardNodeUpdater {
@@ -291,6 +315,43 @@ impl InternalWireGuardNode {
     }
 }
 
+impl Validatable for InternalWireGuardNode {
+    type Error = FabricConfigError;
+
+    /// Validates the [FabricSection<WireGuardNodeProperties>].
+    ///
+    /// Checks if we have either an IPv4 or an IPv6 address. If neither is set, return an error.
+    fn validate(&self) -> Result<(), Self::Error> {
+        let mut local_interfaces = HashSet::new();
+        let mut listen_ports = HashSet::new();
+
+        for interface in self.interfaces() {
+            // check if interface names are unique
+            if !local_interfaces.insert(&interface.name) {
+                return Err(FabricConfigError::DuplicateInterface);
+            }
+
+            // check if listen ports are unique
+            if !listen_ports.insert(interface.listen_port) {
+                return Err(FabricConfigError::DuplicatePort(
+                    interface.listen_port.to_string(),
+                ));
+            }
+        }
+
+        for peer in self.peers() {
+            if let WireGuardNodePeer::Internal(peer) = peer {
+                // check if referenced local interface exists
+                if !local_interfaces.contains(&peer.iface) {
+                    return Err(FabricConfigError::InvalidInterfaceReference);
+                }
+            }
+        }
+
+        Ok(())
+    }
+}
+
 #[api(
     properties: {
         allowed_ips: {
-- 
2.47.3