diff --git a/Cargo.lock b/Cargo.lock
index 83d70890c3..880db7f100 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -11,6 +11,18 @@ dependencies = [
  "memchr",
 ]
 
+[[package]]
+name = "argon2"
+version = "0.5.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3c3610892ee6e0cbce8ae2700349fcf8f98adb0dbfbee85aec3c9179d29cc072"
+dependencies = [
+ "base64ct",
+ "blake2",
+ "cpufeatures",
+ "password-hash",
+]
+
 [[package]]
 name = "autocfg"
 version = "1.4.0"
@@ -40,6 +52,15 @@ version = "2.9.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5c8214115b7bf84099f1309324e63141d4c5d7cc26862f97a0a857dbefe165bd"
 
+[[package]]
+name = "blake2"
+version = "0.10.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "46502ad458c9a52b69d4d4d32775c788b7a1b85e8bc9d482d92250fc0e3f8efe"
+dependencies = [
+ "digest",
+]
+
 [[package]]
 name = "block-buffer"
 version = "0.10.4"
@@ -498,6 +519,7 @@ checksum = "2b15c43186be67a4fd63bee50d0303afffcef381492ebe2c5d87f324e1b8815c"
 name = "relibc"
 version = "0.2.5"
 dependencies = [
+ "argon2",
  "base64ct",
  "bcrypt-pbkdf",
  "bitflags",
diff --git a/Cargo.toml b/Cargo.toml
index 239f8f16f0..18761f273e 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -51,6 +51,7 @@ chrono = {version = "0.4", default-features = false, features = ["alloc"]}
 libm = "0.2"
 object = { version = "0.36.7", git = "https://gitlab.redox-os.org/andypython/object", default-features = false, features = ["elf", "read_core"] }
 spin = "0.9.8"
+argon2 = "0.5.3"
 
 [dependencies.dlmalloc]
 path = "dlmalloc-rs"
diff --git a/src/header/crypt/argon2.rs b/src/header/crypt/argon2.rs
new file mode 100644
index 0000000000..87cb641f29
--- /dev/null
+++ b/src/header/crypt/argon2.rs
@@ -0,0 +1,16 @@
+use alloc::string::{String, ToString};
+use argon2::{
+    password_hash::{PasswordHash, PasswordVerifier},
+    Argon2,
+};
+
+pub fn crypt_argon2(key: &str, setting: &str) -> Option<String> {
+    let hash = PasswordHash::new(setting).ok()?;
+    let argon2 = Argon2::default();
+
+    if argon2.verify_password(key.as_bytes(), &hash).is_ok() {
+        Some(setting.to_string())
+    } else {
+        None
+    }
+}
diff --git a/src/header/crypt/mod.rs b/src/header/crypt/mod.rs
index 32fe2359b7..b944d34255 100644
--- a/src/header/crypt/mod.rs
+++ b/src/header/crypt/mod.rs
@@ -19,6 +19,7 @@ use crate::{
     platform::{self, types::*},
 };
 
+mod argon2;
 mod blowfish;
 mod md5;
 mod pbkdf2;
@@ -26,6 +27,7 @@ mod scrypt;
 mod sha;
 
 use self::{
+    argon2::crypt_argon2,
     blowfish::crypt_blowfish,
     md5::crypt_md5,
     pbkdf2::crypt_pbkdf2,
@@ -73,21 +75,22 @@ pub unsafe extern "C" fn crypt_r(
     let setting = unsafe { CStr::from_ptr(setting) }
         .to_str()
         .expect("setting must be utf-8");
-    let setting_bytes = setting.as_bytes();
 
-    let encoded = if setting_bytes[0] == b'$' && setting_bytes[1] != 0 && setting_bytes[2] != 0 {
-        if setting_bytes[1] == b'1' && setting_bytes[2] == b'$' {
+    let encoded = if setting.starts_with('$') {
+        if setting.starts_with("$1$") {
             crypt_md5(key, setting)
-        } else if setting_bytes[1] == b'2' && setting_bytes[3] == b'$' {
+        } else if setting.starts_with("$2") && setting.as_bytes().get(3) == Some(&b'$') {
             crypt_blowfish(key, setting)
-        } else if setting_bytes[1] == b'5' && setting_bytes[2] == b'$' {
+        } else if setting.starts_with("$5$") {
             crypt_sha(key, setting, Sha256)
-        } else if setting_bytes[1] == b'6' && setting_bytes[2] == b'$' {
+        } else if setting.starts_with("$6$") {
             crypt_sha(key, setting, Sha512)
-        } else if setting_bytes[1] == b'7' && setting_bytes[2] == b'$' {
+        } else if setting.starts_with("$7$") {
             crypt_scrypt(key, setting)
-        } else if setting_bytes[1] == b'8' && setting_bytes[2] == b'$' {
+        } else if setting.starts_with("$8$") {
             crypt_pbkdf2(key, setting)
+        } else if setting.starts_with("$argon2") {
+            crypt_argon2(key, setting)
         } else {
             platform::ERRNO.set(EINVAL);
             return ptr::null_mut();