feat: add user account verification (#2190)

* add verified column to users table

* add database functions to check if verified, or to verify

* getting there

* verification check

* use base64 urlsafe no pad

* add verification client

* clippy

* correct docs

* fix integration tests

9 files changed, 246 insertions, 11 deletions

diff --git a/crates/atuin-server-database/src/lib.rs b/crates/atuin-server-database/src/lib.rs
index d2c16b3d..f6933b94 100644
--- a/crates/atuin-server-database/src/lib.rs
+++ b/crates/atuin-server-database/src/lib.rs
@@ -53,6 +53,11 @@ pub trait Database: Sized + Clone + Send + Sync + 'static {
     async fn get_user(&self, username: &str) -> DbResult<User>;
     async fn get_user_session(&self, u: &User) -> DbResult<Session>;
     async fn add_user(&self, user: &NewUser) -> DbResult<i64>;
+
+    async fn user_verified(&self, id: i64) -> DbResult<bool>;
+    async fn verify_user(&self, id: i64) -> DbResult<()>;
+    async fn user_verification_token(&self, id: i64) -> DbResult<String>;
+
     async fn update_user_password(&self, u: &User) -> DbResult<()>;
 
     async fn total_history(&self) -> DbResult<i64>;
diff --git a/crates/atuin-server-database/src/models.rs b/crates/atuin-server-database/src/models.rs
index b71a9bc9..894ac7f6 100644
--- a/crates/atuin-server-database/src/models.rs
+++ b/crates/atuin-server-database/src/models.rs
@@ -32,6 +32,7 @@ pub struct User {
     pub username: String,
     pub email: String,
     pub password: String,
+    pub verified: Option<OffsetDateTime>,
 }
 
 pub struct Session {
diff --git a/crates/atuin-server-postgres/migrations/20240621110731_user-verified.sql b/crates/atuin-server-postgres/migrations/20240621110731_user-verified.sql
new file mode 100644
index 00000000..6eba02ec
--- /dev/null
+++ b/crates/atuin-server-postgres/migrations/20240621110731_user-verified.sql
@@ -0,0 +1,8 @@
+alter table users add verified_at timestamp with time zone default null;
+
+create table user_verification_token(
+  id bigserial primary key, 
+  user_id bigint unique references users(id), 
+  token text, 
+  valid_until timestamp with time zone
+);
diff --git a/crates/atuin-server-postgres/src/lib.rs b/crates/atuin-server-postgres/src/lib.rs
index 8a010195..7aa87424 100644
--- a/crates/atuin-server-postgres/src/lib.rs
+++ b/crates/atuin-server-postgres/src/lib.rs
@@ -3,6 +3,7 @@ use std::ops::Range;
 
 use async_trait::async_trait;
 use atuin_common::record::{EncryptedData, HostId, Record, RecordIdx, RecordStatus};
+use atuin_common::utils::crypto_random_string;
 use atuin_server_database::models::{History, NewHistory, NewSession, NewUser, Session, User};
 use atuin_server_database::{Database, DbError, DbResult};
 use futures_util::TryStreamExt;
@@ -11,7 +12,7 @@ use sqlx::postgres::PgPoolOptions;
 use sqlx::Row;
 
 use time::{OffsetDateTime, PrimitiveDateTime, UtcOffset};
-use tracing::instrument;
+use tracing::{instrument, trace};
 use uuid::Uuid;
 use wrappers::{DbHistory, DbRecord, DbSession, DbUser};
 
@@ -100,18 +101,100 @@ impl Database for Postgres {
 
     #[instrument(skip_all)]
     async fn get_user(&self, username: &str) -> DbResult<User> {
-        sqlx::query_as("select id, username, email, password from users where username = $1")
-            .bind(username)
-            .fetch_one(&self.pool)
-            .await
-            .map_err(fix_error)
-            .map(|DbUser(user)| user)
+        sqlx::query_as(
+            "select id, username, email, password, verified_at from users where username = $1",
+        )
+        .bind(username)
+        .fetch_one(&self.pool)
+        .await
+        .map_err(fix_error)
+        .map(|DbUser(user)| user)
+    }
+
+    #[instrument(skip_all)]
+    async fn user_verified(&self, id: i64) -> DbResult<bool> {
+        let res: (bool,) =
+            sqlx::query_as("select verified_at is not null from users where id = $1")
+                .bind(id)
+                .fetch_one(&self.pool)
+                .await
+                .map_err(fix_error)?;
+
+        Ok(res.0)
+    }
+
+    #[instrument(skip_all)]
+    async fn verify_user(&self, id: i64) -> DbResult<()> {
+        sqlx::query(
+            "update users set verified_at = (current_timestamp at time zone 'utc') where id=$1",
+        )
+        .bind(id)
+        .execute(&self.pool)
+        .await
+        .map_err(fix_error)?;
+
+        Ok(())
+    }
+
+    /// Return a valid verification token for the user
+    /// If the user does not have any token, create one, insert it, and return
+    /// If the user has a token, but it's invalid, delete it, create a new one, return
+    /// If the user already has a valid token, return it
+    #[instrument(skip_all)]
+    async fn user_verification_token(&self, id: i64) -> DbResult<String> {
+        const TOKEN_VALID_MINUTES: i64 = 15;
+
+        // First we check if there is a verification token
+        let token: Option<(String, sqlx::types::time::OffsetDateTime)> = sqlx::query_as(
+            "select token, valid_until from user_verification_token where user_id = $1",
+        )
+        .bind(id)
+        .fetch_optional(&self.pool)
+        .await
+        .map_err(fix_error)?;
+
+        let token = if let Some((token, valid_until)) = token {
+            trace!("Token for user {id} valid until {valid_until}");
+
+            // We have a token, AND it's still valid
+            if valid_until > time::OffsetDateTime::now_utc() {
+                token
+            } else {
+                // token has expired. generate a new one, return it
+                let token = crypto_random_string::<24>();
+
+                sqlx::query("update user_verification_token set token = $2, valid_until = $3 where user_id=$1")
+                    .bind(id)
+                    .bind(&token)
+                    .bind(time::OffsetDateTime::now_utc() + time::Duration::minutes(TOKEN_VALID_MINUTES))
+                    .execute(&self.pool)
+                    .await
+                    .map_err(fix_error)?;
+
+                token
+            }
+        } else {
+            // No token in the database! Generate one, insert it
+            let token = crypto_random_string::<24>();
+
+            sqlx::query("insert into user_verification_token (user_id, token, valid_until) values ($1, $2, $3)")
+                .bind(id)
+                .bind(&token)
+                .bind(time::OffsetDateTime::now_utc() + time::Duration::minutes(TOKEN_VALID_MINUTES))
+                .execute(&self.pool)
+                .await
+                .map_err(fix_error)?;
+
+            token
+        };
+
+        Ok(token)
     }
 
     #[instrument(skip_all)]
     async fn get_session_user(&self, token: &str) -> DbResult<User> {
         sqlx::query_as(
-            "select users.id, users.username, users.email, users.password from users 
+            "select users.id, users.username, users.email, users.password, users.verified_at from users 
             inner join sessions 
             on users.id = sessions.user_id 
             and sessions.token = $1",
diff --git a/crates/atuin-server-postgres/src/wrappers.rs b/crates/atuin-server-postgres/src/wrappers.rs
index 3ccf9c19..80f95f21 100644
--- a/crates/atuin-server-postgres/src/wrappers.rs
+++ b/crates/atuin-server-postgres/src/wrappers.rs
@@ -16,6 +16,7 @@ impl<'a> FromRow<'a, PgRow> for DbUser {
             username: row.try_get("username")?,
             email: row.try_get("email")?,
             password: row.try_get("password")?,
+            verified: row.try_get("verified_at")?,
         }))
     }
 }
diff --git a/crates/atuin-server/Cargo.toml b/crates/atuin-server/Cargo.toml
index b076a466..089fe715 100644
--- a/crates/atuin-server/Cargo.toml
+++ b/crates/atuin-server/Cargo.toml
@@ -37,3 +37,4 @@ argon2 = "0.5"
 semver = { workspace = true }
 metrics-exporter-prometheus = "0.12.1"
 metrics = "0.21.1"
+postmark = {version= "0.10.0", features=["reqwest"]}
diff --git a/crates/atuin-server/src/handlers/user.rs b/crates/atuin-server/src/handlers/user.rs
index 8e53dd49..7fd1a4a2 100644
--- a/crates/atuin-server/src/handlers/user.rs
+++ b/crates/atuin-server/src/handlers/user.rs
@@ -12,9 +12,11 @@ use axum::{
     Json,
 };
 use metrics::counter;
+
+use postmark::{reqwest::PostmarkClient, Query};
+
 use rand::rngs::OsRng;
 use tracing::{debug, error, info, instrument};
-use uuid::Uuid;
 
 use super::{ErrorResponse, ErrorResponseStatus, RespExt};
 use crate::router::{AppState, UserAuth};
@@ -25,7 +27,7 @@ use atuin_server_database::{
 
 use reqwest::header::CONTENT_TYPE;
 
-use atuin_common::api::*;
+use atuin_common::{api::*, utils::crypto_random_string};
 
 pub fn verify_str(hash: &str, password: &str) -> bool {
     let arg2 = Argon2::new(Algorithm::Argon2id, Version::V0x13, Params::default());
@@ -126,7 +128,8 @@ pub async fn register<DB: Database>(
         }
     };
 
-    let token = Uuid::new_v4().as_simple().to_string();
+    // 24 bytes encoded as base64
+    let token = crypto_random_string::<24>();
 
     let new_session = NewSession {
         user_id,
@@ -175,6 +178,107 @@ pub async fn delete<DB: Database>(
     Ok(Json(DeleteUserResponse {}))
 }
 
+#[instrument(skip_all, fields(user.id = user.id))]
+pub async fn send_verification<DB: Database>(
+    UserAuth(user): UserAuth,
+    state: State<AppState<DB>>,
+) -> Result<Json<SendVerificationResponse>, ErrorResponseStatus<'static>> {
+    let settings = state.0.settings;
+
+    if !settings.mail.enabled {
+        return Ok(Json(SendVerificationResponse {
+            email_sent: false,
+            verified: false,
+        }));
+    }
+
+    if user.verified.is_some() {
+        return Ok(Json(SendVerificationResponse {
+            email_sent: false,
+            verified: true,
+        }));
+    }
+
+    // TODO: if we ever add another mail provider, can match on them all here.
+    let postmark_token = if let Some(token) = settings.mail.postmark.token {
+        token
+    } else {
+        return Err(ErrorResponse::reply("mail not configured")
+            .with_status(StatusCode::INTERNAL_SERVER_ERROR));
+    };
+
+    let db = &state.0.database;
+
+    let verification_token = db
+        .user_verification_token(user.id)
+        .await
+        .expect("Failed to verify");
+
+    debug!("Generated verification token, emailing user");
+
+    let client = PostmarkClient::builder()
+        .base_url("https://api.postmarkapp.com/")
+        .token(postmark_token)
+        .build();
+
+    let req = postmark::api::email::SendEmailRequest::builder()
+        .from(settings.mail.verification.from)
+        .subject(settings.mail.verification.subject)
+        .to(user.email)
+        .body(postmark::api::Body::text(format!(
+            "Please run the following command to finalize your Atuin account verification. It is valid for 15 minutes:\n\natuin account verify --token '{}'",
+            verification_token
+        )))
+        .build();
+
+    req.execute(&client)
+        .await
+        .expect("postmark email request failed");
+
+    debug!("Email sent");
+
+    Ok(Json(SendVerificationResponse {
+        email_sent: true,
+        verified: false,
+    }))
+}
+
+#[instrument(skip_all, fields(user.id = user.id))]
+pub async fn verify_user<DB: Database>(
+    UserAuth(user): UserAuth,
+    state: State<AppState<DB>>,
+    Json(token_request): Json<VerificationTokenRequest>,
+) -> Result<Json<VerificationTokenResponse>, ErrorResponseStatus<'static>> {
+    let db = state.0.database;
+
+    if user.verified.is_some() {
+        return Ok(Json(VerificationTokenResponse { verified: true }));
+    }
+
+    let token = db.user_verification_token(user.id).await.map_err(|e| {
+        error!("Failed to read user token: {e}");
+
+        ErrorResponse::reply("Failed to verify").with_status(StatusCode::INTERNAL_SERVER_ERROR)
+    })?;
+
+    if token_request.token == token {
+        db.verify_user(user.id).await.map_err(|e| {
+            error!("Failed to verify user: {e}");
+
+            ErrorResponse::reply("Failed to verify").with_status(StatusCode::INTERNAL_SERVER_ERROR)
+        })?;
+    } else {
+        info!(
+            "Incorrect verification token {} vs {}",
+            token_request.token, token
+        );
+
+        return Ok(Json(VerificationTokenResponse { verified: false }));
+    }
+
+    Ok(Json(VerificationTokenResponse { verified: true }))
+}
+
 #[instrument(skip_all, fields(user.id = user.id, change_password))]
 pub async fn change_password<DB: Database>(
     UserAuth(mut user): UserAuth,
diff --git a/crates/atuin-server/src/router.rs b/crates/atuin-server/src/router.rs
index 96dff2bd..df3a2937 100644
--- a/crates/atuin-server/src/router.rs
+++ b/crates/atuin-server/src/router.rs
@@ -126,6 +126,11 @@ pub fn router<DB: Database>(database: DB, settings: Settings<DB::Settings>) -> R
         .route("/record", get(handlers::record::index::<DB>))
         .route("/record/next", get(handlers::record::next))
         .route("/api/v0/me", get(handlers::v0::me::get))
+        .route("/api/v0/account/verify", post(handlers::user::verify_user))
+        .route(
+            "/api/v0/account/send-verification",
+            post(handlers::user::send_verification),
+        )
         .route("/api/v0/record", post(handlers::v0::record::post))
         .route("/api/v0/record", get(handlers::v0::record::index))
         .route("/api/v0/record/next", get(handlers::v0::record::next))
diff --git a/crates/atuin-server/src/settings.rs b/crates/atuin-server/src/settings.rs
index 286b5688..1246982a 100644
--- a/crates/atuin-server/src/settings.rs
+++ b/crates/atuin-server/src/settings.rs
@@ -7,8 +7,34 @@ use serde::{de::DeserializeOwned, Deserialize, Serialize};
 
 static EXAMPLE_CONFIG: &str = include_str!("../server.toml");
 
+#[derive(Default, Clone, Debug, Deserialize, Serialize)]
+pub struct Mail {
+    #[serde(alias = "enable")]
+    pub enabled: bool,
+
+    /// Configuration for the postmark api client
+    /// This is what we use for Atuin Cloud, the forum, etc.
+    pub postmark: Postmark,
+
+    pub verification: MailVerification,
+}
+
+#[derive(Default, Clone, Debug, Deserialize, Serialize)]
+pub struct Postmark {
+    #[serde(alias = "enable")]
+    pub token: Option<String>,
+}
+
+#[derive(Default, Clone, Debug, Deserialize, Serialize)]
+pub struct MailVerification {
+    #[serde(alias = "enable")]
+    pub from: String,
+    pub subject: String,
+}
+
 #[derive(Clone, Debug, Deserialize, Serialize)]
 pub struct Metrics {
+    #[serde(alias = "enabled")]
     pub enable: bool,
     pub host: String,
     pub port: u16,
@@ -37,6 +63,7 @@ pub struct Settings<DbSettings> {
     pub register_webhook_username: String,
     pub metrics: Metrics,
     pub tls: Tls,
+    pub mail: Mail,
 
     #[serde(flatten)]
     pub db_settings: DbSettings,