Fix multibyte meshcore-decoder dep hell

frontend/lib/meshcore-decoder/lib/build-wasm.sh

@@ -0,0 +1,27 @@
+#!/bin/bash
+
+# Build orlp/ed25519 WebAssembly module
+
+set -e
+
+echo "Building orlp/ed25519 WebAssembly module..."
+
+# Compile all orlp source files + our wrapper to WASM
+emcc \
+  -O3 \
+  -s WASM=1 \
+  -s EXPORTED_FUNCTIONS='["_orlp_derive_public_key", "_orlp_validate_keypair", "_orlp_sign", "_orlp_verify"]' \
+  -s EXPORTED_RUNTIME_METHODS='["ccall", "cwrap", "HEAPU8", "HEAP8", "HEAPU32", "HEAP32"]' \
+  -s MODULARIZE=1 \
+  -s EXPORT_NAME="OrlpEd25519" \
+  -s ALLOW_MEMORY_GROWTH=1 \
+  -s NO_EXIT_RUNTIME=1 \
+  -I orlp-ed25519/src \
+  orlp-ed25519/src/*.c \
+  orlp-ed25519-wrapper.c \
+  -o orlp-ed25519.js
+
+echo "WebAssembly module built successfully!"
+echo "Generated files:"
+echo "  - orlp-ed25519.js (JavaScript loader)"
+echo "  - orlp-ed25519.wasm (WebAssembly binary)"

frontend/lib/meshcore-decoder/lib/orlp-ed25519-wrapper.c

@@ -0,0 +1,65 @@
+#include "orlp-ed25519/src/ed25519.h"
+#include <emscripten.h>
+
+// WebAssembly wrapper for orlp/ed25519 key derivation
+
+EMSCRIPTEN_KEEPALIVE
+int orlp_derive_public_key(unsigned char *public_key, const unsigned char *private_key) {
+    // Use orlp's ed25519_create_keypair logic but only for key derivation
+    // The private_key is already the 64-byte orlp format
+    
+    // Extract the first 32 bytes (the actual scalar)
+    unsigned char scalar[32];
+    for (int i = 0; i < 32; i++) {
+        scalar[i] = private_key[i];
+    }
+    
+    // Check orlp precondition
+    if (scalar[31] > 127) {
+        return -1; // Invalid scalar
+    }
+    
+    // Use orlp's internal ge_scalarmult_base function
+    // This is declared in ge.h but we need to access it
+    extern void ge_scalarmult_base(void *h, const unsigned char *a);
+    extern void ge_p3_tobytes(unsigned char *s, const void *h);
+    
+    // Allocate space for ge_p3 point (we don't know the exact size, but it's small)
+    unsigned char point[128]; // Should be enough for ge_p3 structure
+    
+    // Perform scalar multiplication: point = scalar * base_point
+    ge_scalarmult_base(point, scalar);
+    
+    // Convert point to bytes
+    ge_p3_tobytes(public_key, point);
+    
+    return 0; // Success
+}
+
+EMSCRIPTEN_KEEPALIVE
+int orlp_validate_keypair(const unsigned char *public_key, const unsigned char *private_key) {
+    unsigned char derived_public[32];
+    
+    if (orlp_derive_public_key(derived_public, private_key) != 0) {
+        return 0; // Derivation failed
+    }
+    
+    // Compare derived public key with expected
+    for (int i = 0; i < 32; i++) {
+        if (derived_public[i] != public_key[i]) {
+            return 0; // Mismatch
+        }
+    }
+    
+    return 1; // Match
+}
+
+EMSCRIPTEN_KEEPALIVE
+void orlp_sign(unsigned char *signature, const unsigned char *message, size_t message_len, const unsigned char *public_key, const unsigned char *private_key) {
+    ed25519_sign(signature, message, message_len, public_key, private_key);
+}
+
+EMSCRIPTEN_KEEPALIVE
+int orlp_verify(const unsigned char *signature, const unsigned char *message, size_t message_len, const unsigned char *public_key) {
+    return ed25519_verify(signature, message, message_len, public_key);
+}