From 7038f65ac6160351075ccc7f524f8ba25fc61ad0 Mon Sep 17 00:00:00 2001
From: Aaron Kaiser <a_kaiser@posteo.de>
Date: Tue, 23 Apr 2024 10:33:59 +0200
Subject: [PATCH] Implemented keygen and x25519 for agent

---
 src/agent.jazz | 36 +++++++++++++++++++++++++++++-------
 1 file changed, 29 insertions(+), 7 deletions(-)

diff --git a/src/agent.jazz b/src/agent.jazz
index 4667b2f..0d7902e 100644
--- a/src/agent.jazz
+++ b/src/agent.jazz
@@ -1,5 +1,14 @@
 from Jade require "crypto_scalarmult/curve25519/amd64/mulx/scalarmult.jazz"
 
+inline fn extract_nth_ptr(reg u64 sync_mem shared_mem, inline int i) -> reg u64 {
+    reg u64 p;
+
+    p = (u64)[sync_mem + (16 + i * 8)];
+    p += shared_mem;
+
+    return p;
+}
+
 inline fn extract_ipc_id(reg u64 sync_mem) -> reg u64 {
     reg u64 id;
 
@@ -8,7 +17,7 @@ inline fn extract_ipc_id(reg u64 sync_mem) -> reg u64 {
     return id;
 }
 
-inline fn generate_key(reg u64 shared_mem sync_mem private_mem key_id) -> reg u64 {
+inline fn generate_key(reg u64 shared_mem sync_mem private_mem, stack u64 key_id) -> stack u64 {
     inline int i;
     stack u8[32] key;
     reg u64 addr idptr pkptr;
@@ -35,18 +44,28 @@ inline fn generate_key(reg u64 shared_mem sync_mem private_mem key_id) -> reg u6
     pkptr = (u64)[sync_mem + 24];
     pkptr += shared_mem;
 
-    () = #spill(key_id);
-
     jade_scalarmult_curve25519_amd64_mulx_base(pkptr, private_mem);
 
-    () = #unspill(key_id);
-
     return key_id;
 }
 
+inline fn x25519(reg u64 shared_mem sync_mem private_mem) {
+    reg u64 outptr idptr pkptr keyptr;
+    stack u64 keyid;
+
+    outptr = extract_nth_ptr(sync_mem, shared_mem, 0);
+    idptr = extract_nth_ptr(sync_mem, shared_mem, 1);
+    pkptr = extract_nth_ptr(sync_mem, shared_mem, 2);
+
+    keyid = (u64)[idptr];
+    keyptr = private_mem + keyid;
+
+    jade_scalarmult_curve25519_amd64_mulx(outptr, keyptr, pkptr);
+}
+
 export fn agent_start(reg u64 shared_mem sync_mem private_mem) {
     stack u8[8] unused;
-    reg u64 key_id;
+    stack u64 key_id;
 
     key_id = 0;
 
@@ -60,11 +79,14 @@ export fn agent_start(reg u64 shared_mem sync_mem private_mem) {
         () = #unspill(shared_mem, sync_mem, private_mem);
         
         reg u64 id;
-
         id = extract_ipc_id(sync_mem);
 
         if (id == 0) {
             key_id = generate_key(shared_mem, sync_mem, private_mem, key_id);
+        } else {
+            if (id == 1) {
+                x25519(shared_mem, sync_mem, private_mem);
+            }
         }
 
         () = #unspill(sync_mem);