From 0eae5818a07b92908e02684d8f5c3faf0af08353 Mon Sep 17 00:00:00 2001
From: "Gu://em_" <guillem.george@epita.fr>
Date: Fri, 3 Jul 2026 21:56:17 +0200
Subject: [PATCH] Made some advancements on the cryptographic primitives
 implementation

---
 src/crypto.zig         |  1 -
 src/crypto/aes.zig     |  4 ++++
 src/crypto/ed25519.zig | 43 +++++++++++++++++++++++++++---------------
 src/crypto/hkdf.zig    |  2 ++
 src/crypto/hmac.zig    |  8 ++++++++
 src/crypto/sha256.zig  | 11 +++++++++++
 src/crypto/sha512.zig  | 11 +++++++++++
 src/crypto/x25519.zig  |  6 +++++-
 8 files changed, 69 insertions(+), 17 deletions(-)

diff --git a/src/crypto.zig b/src/crypto.zig
index 5027da2..679c46d 100644
--- a/src/crypto.zig
+++ b/src/crypto.zig
@@ -54,7 +54,6 @@ pub fn resolveEngine(comptime provider: PartialEngine) Engine {
         .sha512     = provider.sha512     orelse SHA512.DefaultImplementation,
         .x25519     = provider.x25519     orelse X25519.DefaultImplementation,
     };
-
 }
 
 
diff --git a/src/crypto/aes.zig b/src/crypto/aes.zig
index 853f39f..df886b2 100644
--- a/src/crypto/aes.zig
+++ b/src/crypto/aes.zig
@@ -10,6 +10,10 @@ pub const CBC256_Implementation = struct {
 
 // TODO
 pub const CBC265_DefaultImplementation = struct {
+
+    // Zig stdlib seems to provide no support for AES CBC265
+    // It may need some custom implementation or another library
+
     pub fn encrypt(key: *const [32]u8, iv: *const [16]u8, data: *const []u8) !void {
         _ = key;
         _ = iv;
diff --git a/src/crypto/ed25519.zig b/src/crypto/ed25519.zig
index 2da4bc1..e58c993 100644
--- a/src/crypto/ed25519.zig
+++ b/src/crypto/ed25519.zig
@@ -9,21 +9,34 @@ pub const Implementation = struct {
 };
 
 // TODO
-pub const defaultImplementation = struct {
+pub fn defaultImplementation() type {
 
-    pub fn generateKeys(privkey_buffer: *[32]u8) !void {
-        _ = privkey_buffer;
-    }
-    
-    pub fn sign(key: *const [32]u8, data: *const []const u8, signature_out: *const [64]u8) !void {
-        _ = key;
-        _ = data;
-        _ = signature_out;
-    }
+    const Ed25519 = @import("std").crypto.sign.Ed25519;
+    _ = Ed25519;
 
-    pub fn verify(signature: *const [64]u8, data: *const []const u8) !void {
-        _ = signature;
-        _ = data;
-    }
+    // Again, some Ed25519 functions seem to rely on the io module that is not necessarily available on embedded systems
+    // It may need some custom implementation or other library
+
+    return struct {
+        
+        pub fn generateKeys(pubkey_buffer: *[32]u8, privkey_buffer: *[32]u8) !void {
+            _ = pubkey_buffer;
+            _ = privkey_buffer;
+            return error.NotImplemented;
+
+        }
     
-};
+        pub fn sign(key: *const [32]u8, data: *const []const u8, signature_out: *const [64]u8) !void {
+            _ = key;
+            _ = data;
+            _ = signature_out;
+            return error.NotImplemented;
+        }
+
+        pub fn verify(signature: *const [64]u8, data: *const []const u8) !void {
+            _ = signature;
+            _ = data;
+            return error.NotImplemented;
+        }
+    };
+}
diff --git a/src/crypto/hkdf.zig b/src/crypto/hkdf.zig
index 5344700..f1e9458 100644
--- a/src/crypto/hkdf.zig
+++ b/src/crypto/hkdf.zig
@@ -4,4 +4,6 @@ pub const Implementation = struct {
 
 pub const defaultImplementation = struct {
     
+    const Hkdf = @import("std").crypto.kdf.hkdf.Hkdf;
+
 };
diff --git a/src/crypto/hmac.zig b/src/crypto/hmac.zig
index 5344700..cb096e8 100644
--- a/src/crypto/hmac.zig
+++ b/src/crypto/hmac.zig
@@ -4,4 +4,12 @@ pub const Implementation = struct {
 
 pub const defaultImplementation = struct {
     
+    const Hmac = @import("std").crypto.auth.hmac.Hmac;
+
+    pub fn create(out: []u8, msg: []const u8, key: []const u8) !void {
+        _ = out;
+        _ = msg;
+        _ = key;
+        return error.NotImplemented;
+    }
 };
diff --git a/src/crypto/sha256.zig b/src/crypto/sha256.zig
index 5344700..70478e0 100644
--- a/src/crypto/sha256.zig
+++ b/src/crypto/sha256.zig
@@ -1,7 +1,18 @@
 pub const Implementation = struct {
     
+    hash: *const fn (buffer: []const u8, out: []u8) void,
 };
 
 pub const defaultImplementation = struct {
     
+    const Sha256 = @import("std").crypto.hash.sha2.Sha256;
+
+    const HASH_LEN = 32; // In bytes
+
+    pub fn hash(buffer: []const u8, out: []u8) !void {
+        if (out.len < HASH_LEN) {
+            return error.BufferTooShort;
+        }
+        Sha256.hash(buffer, out, .{});
+    }
 };
diff --git a/src/crypto/sha512.zig b/src/crypto/sha512.zig
index 5344700..a69a88d 100644
--- a/src/crypto/sha512.zig
+++ b/src/crypto/sha512.zig
@@ -1,7 +1,18 @@
 pub const Implementation = struct {
     
+    hash: *const fn (buffer: []const u8, out: []u8) void,
 };
 
 pub const defaultImplementation = struct {
     
+    const Sha512 = @import("std").crypto.sha2.Sha512;
+
+    const HASH_LEN = 64; // In bytes
+
+    pub fn hash(buffer: []const u8, out: []u8) !void {
+        if (out.len < HASH_LEN) {
+            return error.BufferTooShort;
+        }
+        Sha512.hash(buffer, out, .{});
+    }
 };
diff --git a/src/crypto/x25519.zig b/src/crypto/x25519.zig
index 5344700..f3f6607 100644
--- a/src/crypto/x25519.zig
+++ b/src/crypto/x25519.zig
@@ -3,5 +3,9 @@ pub const Implementation = struct {
 };
 
 pub const defaultImplementation = struct {
-    
+
+    const X25519 = @import("std").std.crypto.dh.X25519;
+
+    // One problem, it uses the zig's io module, which is not supported yet as it depends on the target OS
+    // It may need a custom implementation or some other library
 };