diff --git a/src/server/auth/token.rs b/src/server/auth/token.rs
index 644e533..0a72730 100644
--- a/src/server/auth/token.rs
+++ b/src/server/auth/token.rs
@@ -4,6 +4,7 @@ use crate::db::User;
 use crate::ext::json::ToJson2;
 use crate::ext::try_err::TryErr3;
 use crate::gettext;
+use base64::{engine::general_purpose::STANDARD as base64, Engine};
 use openssl::{hash::MessageDigest, pkcs5::pbkdf2_hmac};
 
 /// Action to perform about token
@@ -45,7 +46,8 @@ impl AuthTokenContext {
                     let password = params
                         .get("password")
                         .ok_or((2, gettext("No password specified.")))?;
-                    let password = base64::decode(password)
+                    let password = base64
+                        .decode(password)
                         .try_err3(3, gettext("Failed to decode password with base64:"))?;
                     let rsa_key = self.ctx.rsa_key.lock().await;
                     let key = rsa_key.as_ref().ok_or((4, gettext("No RSA key found.")))?;
@@ -95,7 +97,7 @@ impl AuthTokenContext {
                             break token;
                         }
                     };
-                    let b64token = base64::encode(&token.token);
+                    let b64token = base64.encode(&token.token);
                     Ok(
                         json::object! { "id": token.id, "user_id": token.user_id, "token": b64token, "created_at": token.created_at.timestamp(), "expired_at": token.expired_at.timestamp() },
                     )
diff --git a/src/server/auth/user.rs b/src/server/auth/user.rs
index e0944fe..4ff311b 100644
--- a/src/server/auth/user.rs
+++ b/src/server/auth/user.rs
@@ -3,6 +3,7 @@ use super::{PASSWORD_ITER, PASSWORD_SALT};
 use crate::ext::json::ToJson2;
 use crate::ext::try_err::{TryErr, TryErr3};
 use crate::gettext;
+use base64::{engine::general_purpose::STANDARD as base64, Engine};
 use bytes::BytesMut;
 use openssl::{hash::MessageDigest, pkcs5::pbkdf2_hmac};
 
@@ -83,7 +84,8 @@ impl AuthUserContext {
                     let password = params
                         .get("password")
                         .try_err((3, gettext("No password specified.")))?;
-                    let password = base64::decode(password)
+                    let password = base64
+                        .decode(password)
                         .try_err3(4, gettext("Failed to decode password with base64:"))?;
                     let rsa_key = self.ctx.rsa_key.lock().await;
                     match *rsa_key {
@@ -188,7 +190,8 @@ impl AuthUserContext {
                     let password = params
                         .get("password")
                         .try_err3(3, "No password specified.")?;
-                    let password = base64::decode(password)
+                    let password = base64
+                        .decode(password)
                         .try_err3(4, gettext("Failed to decode password with base64:"))?;
                     let rsa_key = self.ctx.rsa_key.lock().await;
                     match *rsa_key {
@@ -380,7 +383,8 @@ impl AuthUserContext {
                         }
                     }
                     if let Some(password) = params.get("password") {
-                        let password = base64::decode(password)
+                        let password = base64
+                            .decode(password)
                             .try_err3(4, gettext("Failed to decode password with base64:"))?;
                         let rsa_key = self.ctx.rsa_key.lock().await;
                         match *rsa_key {
diff --git a/src/server/unittest/auth.rs b/src/server/unittest/auth.rs
index bb090d7..19b2ec5 100644
--- a/src/server/unittest/auth.rs
+++ b/src/server/unittest/auth.rs
@@ -2,6 +2,7 @@ use super::UnitTestContext;
 use crate::error::PixivDownloaderError;
 use crate::ext::json::FromJson;
 use crate::server::result::JSONResult;
+use base64::{engine::general_purpose::STANDARD as base64, Engine};
 use bytes::BytesMut;
 use hyper::{Body, Request};
 use openssl::rsa::{Padding, Rsa};
@@ -35,7 +36,7 @@ pub async fn test(ctx: &UnitTestContext) -> Result<[(u64, Vec<u8>); 2], PixivDow
     let mut encypted = BytesMut::with_capacity(tosize);
     encypted.resize(tosize, 0);
     key.public_encrypt(&password, &mut encypted, Padding::PKCS1)?;
-    let b64_password = base64::encode(&encypted);
+    let b64_password = base64.encode(&encypted);
     let re = ctx
         .request_json2(
             "/auth/user/add",
@@ -69,7 +70,7 @@ pub async fn test(ctx: &UnitTestContext) -> Result<[(u64, Vec<u8>); 2], PixivDow
         .unwrap();
     let result = JSONResult::from_json(re)?.expect("Failed to add token:");
     assert_eq!(Some(0), result["user_id"].as_u64());
-    let token = base64::decode(result["token"].as_str().unwrap()).unwrap();
+    let token = base64.decode(result["token"].as_str().unwrap()).unwrap();
     assert_eq!(token.len(), 64);
     let token_id = result["id"].as_u64().unwrap();
     let mut password2 = BytesMut::with_capacity(64);
@@ -78,7 +79,7 @@ pub async fn test(ctx: &UnitTestContext) -> Result<[(u64, Vec<u8>); 2], PixivDow
     let mut encypted2 = BytesMut::with_capacity(tosize);
     encypted2.resize(tosize, 0);
     key.public_encrypt(&password2, &mut encypted2, Padding::PKCS1)?;
-    let b64_password2 = base64::encode(&encypted2);
+    let b64_password2 = base64.encode(&encypted2);
     let re = ctx
         .request_json2_sign(
             "/auth/user/add",
@@ -164,7 +165,7 @@ pub async fn test(ctx: &UnitTestContext) -> Result<[(u64, Vec<u8>); 2], PixivDow
         .unwrap();
     let result = JSONResult::from_json(re)?.expect("Failed to add token:");
     assert_eq!(Some(1), result["user_id"].as_u64());
-    let token2 = base64::decode(result["token"].as_str().unwrap()).unwrap();
+    let token2 = base64.decode(result["token"].as_str().unwrap()).unwrap();
     assert_eq!(token2.len(), 64);
     let token2_id = result["id"].as_u64().unwrap();
     let re = ctx
@@ -302,12 +303,12 @@ pub async fn test(ctx: &UnitTestContext) -> Result<[(u64, Vec<u8>); 2], PixivDow
         .unwrap();
     let result = JSONResult::from_json(re)?.expect("Failed to add token:");
     assert_eq!(Some(1), result["user_id"].as_u64());
-    let token3 = base64::decode(result["token"].as_str().unwrap()).unwrap();
+    let token3 = base64.decode(result["token"].as_str().unwrap()).unwrap();
     assert_eq!(token2.len(), 64);
     let token3_id = result["id"].as_u64().unwrap();
     openssl::rand::rand_bytes(&mut password2)?;
     key.public_encrypt(&password2, &mut encypted2, Padding::PKCS1)?;
-    let b64_password2 = base64::encode(&encypted2);
+    let b64_password2 = base64.encode(&encypted2);
     let re = ctx
         .request_json2_sign(
             "/auth/user/change/password",
@@ -450,7 +451,7 @@ pub async fn test(ctx: &UnitTestContext) -> Result<[(u64, Vec<u8>); 2], PixivDow
     let mut encypted3 = BytesMut::with_capacity(tosize);
     encypted3.resize(tosize, 0);
     key.public_encrypt(&password3, &mut encypted3, Padding::PKCS1)?;
-    let b64_password3 = base64::encode(&encypted3);
+    let b64_password3 = base64.encode(&encypted3);
     let re = ctx
         .request_json2_sign(
             "/auth/user/add",
@@ -487,7 +488,7 @@ pub async fn test(ctx: &UnitTestContext) -> Result<[(u64, Vec<u8>); 2], PixivDow
     let result = JSONResult::from_json(re)?.unwrap();
     assert_eq!(Some(2), result["user_id"].as_u64());
     let token3_id = result["id"].as_u64().unwrap();
-    let token3 = base64::decode(result["token"].as_str().unwrap()).unwrap();
+    let token3 = base64.decode(result["token"].as_str().unwrap()).unwrap();
     let re = ctx
         .request_json2_sign(
             "/auth/user/info",
@@ -603,7 +604,7 @@ pub async fn test(ctx: &UnitTestContext) -> Result<[(u64, Vec<u8>); 2], PixivDow
         .unwrap();
     let result = JSONResult::from_json(re)?.expect("Failed to add token:");
     assert_eq!(Some(1), result["user_id"].as_u64());
-    let token3 = base64::decode(result["token"].as_str().unwrap()).unwrap();
+    let token3 = base64.decode(result["token"].as_str().unwrap()).unwrap();
     assert_eq!(token3.len(), 64);
     let token3_id = result["id"].as_u64().unwrap();
     let re = ctx
@@ -634,7 +635,7 @@ pub async fn test(ctx: &UnitTestContext) -> Result<[(u64, Vec<u8>); 2], PixivDow
         .unwrap();
     let result = JSONResult::from_json(re)?.expect("Failed to add token:");
     assert_eq!(Some(1), result["user_id"].as_u64());
-    let token3 = base64::decode(result["token"].as_str().unwrap()).unwrap();
+    let token3 = base64.decode(result["token"].as_str().unwrap()).unwrap();
     assert_eq!(token3.len(), 64);
     let token3_id = result["id"].as_u64().unwrap();
     let re = ctx
@@ -649,7 +650,7 @@ pub async fn test(ctx: &UnitTestContext) -> Result<[(u64, Vec<u8>); 2], PixivDow
         .unwrap();
     let result = JSONResult::from_json(re)?.expect("Failed to add token:");
     assert_eq!(Some(0), result["user_id"].as_u64());
-    let token4 = base64::decode(result["token"].as_str().unwrap()).unwrap();
+    let token4 = base64.decode(result["token"].as_str().unwrap()).unwrap();
     assert_eq!(token4.len(), 64);
     let token4_id = result["id"].as_u64().unwrap();
     let re = ctx