Implement Credential Management (#67)

Fixes #24

Author: msirringhaus

libwebauthn/examples/cred_management.rs

@@ -0,0 +1,234 @@
+use libwebauthn::management::CredentialManagement;
+use libwebauthn::pin::{PinProvider, StdinPromptPinProvider};
+use libwebauthn::proto::ctap2::{
+    Ctap2, Ctap2CredentialData, Ctap2PublicKeyCredentialRpEntity, Ctap2RPData,
+};
+use libwebauthn::proto::CtapError;
+use libwebauthn::transport::hid::list_devices;
+use libwebauthn::transport::Device;
+use libwebauthn::webauthn::Error as WebAuthnError;
+use std::fmt::Display;
+use std::io::{self, Write};
+use std::time::Duration;
+use text_io::read;
+use tracing_subscriber::{self, EnvFilter};
+
+const TIMEOUT: Duration = Duration::from_secs(10);
+
+fn setup_logging() {
+    tracing_subscriber::fmt()
+        .with_env_filter(EnvFilter::from_default_env())
+        .without_time()
+        .init();
+}
+
+macro_rules! handle_retries {
+    ($res:expr) => {
+        loop {
+            match $res.await {
+                Ok(r) => break r,
+                Err(WebAuthnError::Ctap(ctap_error)) => {
+                    if ctap_error.is_retryable_user_error() {
+                        println!("Oops, try again! Error: {}", ctap_error);
+                        continue;
+                    }
+                    return Err(WebAuthnError::Ctap(ctap_error));
+                }
+                Err(err) => return Err(err),
+            }
+        }
+    };
+}
+
+fn format_rp(rp: &Ctap2PublicKeyCredentialRpEntity) -> String {
+    rp.name.clone().unwrap_or(rp.id.clone())
+}
+
+fn format_credential(cred: &Ctap2CredentialData) -> String {
+    cred.user
+        .display_name
+        .clone()
+        .unwrap_or(cred.user.name.clone().unwrap_or("<No username>".into()))
+        .to_string()
+}
+
+async fn enumerate_rps<T: CredentialManagement>(
+    channel: &mut T,
+    pin_provider: &mut Box<dyn PinProvider>,
+) -> Result<Vec<Ctap2RPData>, WebAuthnError> {
+    let (rp, total_rps) = handle_retries!(channel.enumerate_rps_begin(pin_provider, TIMEOUT));
+    let mut rps = vec![rp];
+    // Starting at 1, as we already have one from the begin-call.
+    for _ in 1..total_rps {
+        let rp = handle_retries!(channel.enumerate_rps_next_rp(pin_provider, TIMEOUT));
+        rps.push(rp);
+    }
+    Ok(rps)
+}
+
+async fn enumerate_credentials_for_rp<T: CredentialManagement>(
+    channel: &mut T,
+    pin_provider: &mut Box<dyn PinProvider>,
+    rp_id_hash: &[u8],
+) -> Result<Vec<Ctap2CredentialData>, WebAuthnError> {
+    let (credential, num_of_creds) =
+        handle_retries!(channel.enumerate_credentials_begin(pin_provider, rp_id_hash, TIMEOUT));
+    let mut credentials = vec![credential];
+    // Starting at 1, as we already have one from the begin-call.
+    for _ in 1..num_of_creds {
+        let credential = handle_retries!(channel.enumerate_credentials_next(pin_provider, TIMEOUT));
+        credentials.push(credential);
+    }
+    Ok(credentials)
+}
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+enum Operation {
+    GetMetadata,
+    EnumerateRPs,
+    EnumerateCredentials,
+    RemoveCredential,
+    UpdateUserInfo,
+}
+
+impl Display for Operation {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            Operation::GetMetadata => f.write_str("Get metadata"),
+            Operation::EnumerateRPs => f.write_str("Enumerate relying parties"),
+            Operation::EnumerateCredentials => f.write_str("Enumerate credentials"),
+            Operation::RemoveCredential => f.write_str("Remove credential"),
+            Operation::UpdateUserInfo => f.write_str("Update user info"),
+        }
+    }
+}
+
+fn ask_for_user_input(num_of_items: usize) -> usize {
+    let idx = loop {
+        print!("Your choice: ");
+        io::stdout().flush().expect("Failed to flush stdout!");
+        let input: String = read!("{}\n");
+        if let Ok(idx) = input.trim().parse::<usize>() {
+            if idx < num_of_items {
+                println!();
+                break idx;
+            }
+        }
+    };
+    idx
+}
+
+#[tokio::main]
+pub async fn main() -> Result<(), WebAuthnError> {
+    setup_logging();
+
+    let devices = list_devices().await.unwrap();
+    println!("Devices found: {:?}", devices);
+    let mut pin_provider: Box<dyn PinProvider> = Box::new(StdinPromptPinProvider::new());
+
+    for mut device in devices {
+        println!("Selected HID authenticator: {}", &device);
+        device.wink(TIMEOUT).await?;
+
+        let mut channel = device.channel().await?;
+        let info = channel.ctap2_get_info().await?;
+
+        if let Some(options) = &info.options {
+            if options.get("credMgmt") != Some(&true) {
+                println!("Your token does not support credential management.");
+                return Err(WebAuthnError::Ctap(CtapError::InvalidCommand));
+            }
+        }
+
+        let options = [
+            Operation::GetMetadata,
+            Operation::EnumerateRPs,
+            Operation::EnumerateCredentials,
+            Operation::RemoveCredential,
+            Operation::UpdateUserInfo,
+        ];
+
+        println!("What do you want to do?");
+        println!();
+        for (idx, op) in options.iter().enumerate() {
+            println!("({idx}) {op}");
+        }
+
+        let idx = ask_for_user_input(options.len());
+        let metadata = handle_retries!(channel.get_credential_metadata(&mut pin_provider, TIMEOUT));
+        if options[idx] == Operation::GetMetadata {
+            println!("Metadata: {metadata:#?}");
+            return Ok(());
+        }
+
+        let rps = enumerate_rps(&mut channel, &mut pin_provider).await?;
+        if options[idx] == Operation::EnumerateRPs {
+            println!("RPs:");
+            for rp in &rps {
+                println!("{}", format_rp(&rp.rp));
+            }
+            return Ok(());
+        }
+
+        let mut credlist = Vec::new();
+        for rp in &rps {
+            let creds =
+                enumerate_credentials_for_rp(&mut channel, &mut pin_provider, &rp.rp_id_hash)
+                    .await?;
+            for cred in creds {
+                credlist.push((rp.rp.clone(), cred));
+            }
+        }
+        if options[idx] == Operation::EnumerateCredentials {
+            println!("Credentials:");
+            for (rp, cred) in &credlist {
+                println!("{}: {}", format_rp(rp), format_credential(cred));
+            }
+            return Ok(());
+        }
+
+        // For all remaining operations, we need to enumerate the found creds
+        for (idx, (rp, cred)) in credlist.iter().enumerate() {
+            println!("({idx}) {}: {}", format_rp(rp), format_credential(cred));
+        }
+
+        let cred_idx = ask_for_user_input(options.len());
+
+        if options[idx] == Operation::RemoveCredential {
+            let (_, cred) = &credlist[cred_idx];
+            handle_retries!(channel.delete_credential(
+                &cred.credential_id,
+                &mut pin_provider,
+                TIMEOUT
+            ));
+            println!("Done");
+            return Ok(());
+        }
+
+        if options[idx] == Operation::UpdateUserInfo {
+            let name = loop {
+                print!("New user name: ");
+                io::stdout().flush().expect("Failed to flush stdout!");
+                let input: String = read!("{}\n");
+                let input = input.trim();
+                if !input.is_empty() {
+                    println!();
+                    break input.to_string();
+                }
+            };
+            let (_rp, cred) = &credlist[cred_idx];
+            let mut user = cred.user.clone();
+            user.name = Some(name);
+            handle_retries!(channel.update_user_info(
+                &cred.credential_id,
+                &user,
+                &mut pin_provider,
+                TIMEOUT
+            ));
+            println!("Done");
+            return Ok(());
+        }
+    }
+
+    Ok(())
+}

libwebauthn/src/management.rs

@@ -3,3 +3,6 @@ pub use bio_enrollment::BioEnrollment;
 
 mod authenticator_config;
 pub use authenticator_config::AuthenticatorConfig;
+
+mod credential_management;
+pub use credential_management::CredentialManagement;