From f18dbd88e0c89260aa73f3bcd864bf7ffa9c2d39 Mon Sep 17 00:00:00 2001
From: Cameron Gutman <aicommander@gmail.com>
Date: Thu, 31 Mar 2016 11:54:06 -0400
Subject: [PATCH] Implement NaCl-side of pairing with Gen 7 servers

---
 libgamestream/pairing.c | 20 +++++++++++++++-----
 libgamestream/pairing.h |  2 +-
 main.cpp                |  2 +-
 3 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/libgamestream/pairing.c b/libgamestream/pairing.c
index 3d7a758..1a795ee 100644
--- a/libgamestream/pairing.c
+++ b/libgamestream/pairing.c
@@ -126,7 +126,7 @@ cleanup:
     return result;
 }
 
-int gs_pair(const char* address, const char* pin) {
+int gs_pair(int serverMajorVersion, const char* address, const char* pin) {
     int ret = GS_OK;
     char url[4096];
     
@@ -143,11 +143,17 @@ int gs_pair(const char* address, const char* pin) {
         goto cleanup;
     
     unsigned char salt_pin[20];
-    unsigned char aes_key_hash[20];
+    unsigned char aes_key_hash[32];
     AES_KEY enc_key, dec_key;
     memcpy(salt_pin, salt_data, 16);
     memcpy(salt_pin+16, pin, 4);
-    SHA1(salt_pin, 20, aes_key_hash);
+    
+    int hash_length = serverMajorVersion >= 7 ? 32 : 20;
+    if (serverMajorVersion >= 7)
+        SHA256(salt_pin, 20, aes_key_hash);
+    else
+        SHA1(salt_pin, 20, aes_key_hash);
+    
     AES_set_encrypt_key((unsigned char *)aes_key_hash, 128, &enc_key);
     AES_set_decrypt_key((unsigned char *)aes_key_hash, 128, &dec_key);
     
@@ -186,10 +192,14 @@ int gs_pair(const char* address, const char* pin) {
     unsigned char challenge_response_hash[32];
     unsigned char challenge_response_hash_enc[32];
     char challenge_response_hex[65];
-    memcpy(challenge_response, challenge_response_data + 20, 16);
+    memcpy(challenge_response, challenge_response_data + hash_length, 16);
     memcpy(challenge_response + 16, g_Cert->signature->data, 256);
     memcpy(challenge_response + 16 + 256, client_secret_data, 16);
-    SHA1(challenge_response, 16 + 256 + 16, challenge_response_hash);
+    
+    if (serverMajorVersion >= 7)
+        SHA256(challenge_response, 16 + 256 + 16, challenge_response_hash);
+    else
+        SHA1(challenge_response, 16 + 256 + 16, challenge_response_hash);
     
     for (int i = 0; i < 32; i += 16) {
         AES_encrypt(&challenge_response_hash[i], &challenge_response_hash_enc[i], &enc_key);
diff --git a/libgamestream/pairing.h b/libgamestream/pairing.h
index 2bc1ea1..2619d04 100644
--- a/libgamestream/pairing.h
+++ b/libgamestream/pairing.h
@@ -23,7 +23,7 @@
 extern "C" {
 #endif
 
-int gs_pair(const char* address, const char* pin);
+int gs_pair(int serverMajorVersion, const char* address, const char* pin);
 
 #ifdef __cplusplus
 }
diff --git a/main.cpp b/main.cpp
index 25d51a9..5318fc5 100644
--- a/main.cpp
+++ b/main.cpp
@@ -223,7 +223,7 @@ void MoonlightInstance::HandlePair(int32_t callbackId, pp::VarArray args) {
 }
 
 void MoonlightInstance::PairCallback(int32_t /*result*/, int32_t callbackId, pp::VarArray args) {
-    int err = gs_pair(args.Get(0).AsString().c_str(), args.Get(1).AsString().c_str());
+    int err = gs_pair(atoi(args.Get(0).AsString().c_str()), args.Get(1).AsString().c_str(), args.Get(2).AsString().c_str());
     
     pp::VarDictionary ret;
     ret.Set("callbackId", pp::Var(callbackId));