diff --git a/Cargo.lock b/Cargo.lock
index ff495d0..31a0ce8 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -298,6 +298,12 @@ dependencies = [
  "nodrop",
 ]
 
+[[package]]
+name = "ascii_utils"
+version = "0.9.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "71938f30533e4d95a6d17aa530939da3842c2ab6f4f84b9dae68447e4129f74a"
+
 [[package]]
 name = "async-trait"
 version = "0.1.31"
@@ -505,6 +511,7 @@ dependencies = [
  "actix-web",
  "encoding_rs",
  "futures",
+ "mailchecker",
  "mysql",
  "percent-encoding",
  "serde",
@@ -654,6 +661,15 @@ version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e88a8acf291dafb59c2d96e8f59828f3838bb1a70398823ade51a84de6a6deed"
 
+[[package]]
+name = "fast_chemail"
+version = "0.9.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "495a39d30d624c2caabe6312bfead73e7717692b44e0b32df168c275a2e8e9e4"
+dependencies = [
+ "ascii_utils",
+]
+
 [[package]]
 name = "flate2"
 version = "1.0.14"
@@ -1068,6 +1084,15 @@ dependencies = [
  "linked-hash-map",
 ]
 
+[[package]]
+name = "mailchecker"
+version = "3.3.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b1aeed7b929850f57cbab30c8569b4eb608d9096096a89d815f99ab9fe2f454d"
+dependencies = [
+ "fast_chemail",
+]
+
 [[package]]
 name = "match_cfg"
 version = "0.1.0"
diff --git a/Cargo.toml b/Cargo.toml
index e3bfbb2..5ee8e40 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -14,4 +14,5 @@ actix-rt = "1.1.1"
 serde = "1.0.110"
 futures = "0.3.5"
 encoding_rs = "0.8.23"
-percent-encoding = "2.1.0"
\ No newline at end of file
+percent-encoding = "2.1.0"
+mailchecker = "3.3.6"
\ No newline at end of file
diff --git a/src/controllers/account_controller.rs b/src/controllers/account_controller.rs
index b8e4f20..1b7f546 100644
--- a/src/controllers/account_controller.rs
+++ b/src/controllers/account_controller.rs
@@ -6,6 +6,14 @@ use crate::controllers::routes::RequestResult;
 /// @author Pierre Hubert
 
 /// Sign in user
-pub fn login_user(request:  &mut HttpRequestHandler) -> RequestResult {
-    request.success("Login user")
+pub fn login_user(request: &mut HttpRequestHandler) -> RequestResult {
+    let email = request.post_email("userMail")?;
+    let password = request.post_string_opt("userPassword", 3, true)?;
+
+    // TODO : limit request
+
+    // Authenticate user
+
+
+    request.success("")
 }
\ No newline at end of file
diff --git a/src/data/http_request_handler.rs b/src/data/http_request_handler.rs
index 755760f..ea03ec0 100644
--- a/src/data/http_request_handler.rs
+++ b/src/data/http_request_handler.rs
@@ -133,12 +133,26 @@ impl HttpRequestHandler {
 
     /// Get a post string
     pub fn post_string(&mut self, name: &str) -> ResultBoxError<String> {
+        self.post_string_opt(name, 1, true)
+    }
+
+    /// Get a post string, specifying minimum length
+    pub fn post_string_opt(&mut self, name: &str, min_length: usize, required: bool)
+                           -> ResultBoxError<String> {
         let param = self.post_parameter(name)?;
 
-        match &param.string {
-            Some(s) => Ok(s.to_string()),
-            None => {
-                Err(self.bad_request(format!("'{}' is not a string!", name)).unwrap_err())
+        match (&param.string, required) {
+            (None, true) =>
+                Err(self.bad_request(format!("'{}' is not a string!", name)).unwrap_err()),
+
+            (None, false) => Ok(String::new()),
+
+            (Some(s), _) => {
+                if s.len() >= min_length {
+                    Ok(s.to_string())
+                } else {
+                    Err(self.bad_request(format!("'{}' is too short!", name)).unwrap_err())
+                }
             }
         }
     }
@@ -155,7 +169,7 @@ impl HttpRequestHandler {
 
 
         if let Some(domain) = &client.domain {
-            let allowed_origin =  match conf().force_https {
+            let allowed_origin = match conf().force_https {
                 true => format!("https://{}", domain),
                 false => format!("http://{}", domain)
             };
@@ -166,7 +180,7 @@ impl HttpRequestHandler {
                     if !s.to_str()?.starts_with(&allowed_origin) {
                         self.bad_request("Use of this client is prohibited from this domain!".to_string())?;
                     }
-                },
+                }
             }
 
             self.headers.insert("Access-Control-Allow-Origin".to_string(), allowed_origin);
@@ -176,4 +190,15 @@ impl HttpRequestHandler {
 
         Ok(())
     }
+
+    /// Get an email included in the request
+    pub fn post_email(&mut self, name: &str) -> ResultBoxError<String> {
+        let mail = self.post_string(name)?;
+
+        if !mailchecker::is_valid(&mail) {
+            self.bad_request("Invalid email address!".to_string())?;
+        }
+
+        Ok(mail)
+    }
 }
\ No newline at end of file