From befa8903a84acd30d041e41ce600bb75d7a7fcec Mon Sep 17 00:00:00 2001
From: roblabla <unfiltered@roblab.la>
Date: Sat, 2 Dec 2017 17:17:39 +0100
Subject: [PATCH] Change the parameters of start

On the switch, `start` takes two parameters : an exception pointer,
and a handle to the main thread. For libtransistor, we'll also add
a third one: a context handle. This should allow ace_loader to start
apps expecting the usual switch treatment, while still providing the
context to libtransistor binaries.
---
 main.c   | 18 +++++++++++-------
 nro.c    | 10 +++++-----
 server.c |  4 ++--
 3 files changed, 18 insertions(+), 14 deletions(-)

diff --git a/main.c b/main.c
index 5da21ca..1e57f4e 100644
--- a/main.c
+++ b/main.c
@@ -35,7 +35,7 @@ typedef struct
 	uint64_t unk3;
 } thread_context_t;
 
-struct sockaddr_in stdout_server_addr =
+static struct sockaddr_in stdout_server_addr =
 {
 	.sin_family = AF_INET,
 	.sin_port = htons(STDOUT_PORT),
@@ -102,7 +102,7 @@ static int stdout_debug(struct _reent *reent, void *v, const char *ptr, int len)
 	return len;
 }
 
-void locate_threads(void *base, uint64_t size, int simple)
+void locate_threads(void *base, uint64_t size, int simple, uint32_t *main_handle)
 {
 	memory_info_t minfo;
 	uint32_t pinfo;
@@ -118,6 +118,9 @@ void locate_threads(void *base, uint64_t size, int simple)
 				printf("- found thread context 0x%016lX at 0x%016lX\n handle: 0x%08X\n SP base: 0x%016lX\n SP mirror: 0x%016lX\n SP size: 0x%016lX\n ptrs 0x%016lX 0x%016lX 0x%016lX\n name: '%.32s'\n", (uint64_t)tc, (uint64_t)base, tc->handle, (uint64_t)tc->sp_base, (uint64_t)tc->sp_mirror, tc->sp_size, (uint64_t)tc->ptr_1c8, (uint64_t)tc->ptr_10_a, (uint64_t)tc->ptr_10_b, tc->name);
 				if(strcmp(tc->name, "MainThread"))
 				{
+					// Back up the handle, before we destroy it later on.
+					if (main_handle != NULL)
+						*main_handle = tc->handle;
 					uint64_t *ptr = tc->sp_mirror;
 					uint64_t sizE = tc->sp_size;
 					uint64_t *bend = wkBase + WK_SIZE;
@@ -158,7 +161,7 @@ void locate_threads(void *base, uint64_t size, int simple)
 	}
 }
 
-int thread_scan(int simple)
+int thread_scan(int simple, uint32_t *main_handle)
 {
 	void *addr = NULL;
 	memory_info_t minfo;
@@ -174,7 +177,7 @@ int thread_scan(int simple)
 		if(minfo.permission == 3 && minfo.memory_type == 12)
 		{
 			printf("- found TLS block\n");
-			locate_threads(minfo.base_addr, minfo.size, simple);
+			locate_threads(minfo.base_addr, minfo.size, simple, main_handle);
 		}
 
 		addr = minfo.base_addr + minfo.size;
@@ -252,9 +255,10 @@ void hook_func(uint64_t arg0)
 	map_base = (void*)0xffffffffffffffff; 
 
 	// kill all threads
-	thread_scan(0);
+	uint32_t main_handle = 0;
+	thread_scan(0, &main_handle);
 	svcSleepThread(1000*1000*1000);
-	thread_scan(1);
+	thread_scan(1, NULL);
 	svcSleepThread(1000*1000*1000);
 
 	// close some handles
@@ -311,7 +315,7 @@ void hook_func(uint64_t arg0)
 
 	// start 'push' server
 	if(!server_init())
-		server_loop();
+		server_loop(main_handle);
 
 crash:
 	exit_loader();
diff --git a/nro.c b/nro.c
index 2475392..2bfbfad 100644
--- a/nro.c
+++ b/nro.c
@@ -24,9 +24,9 @@ static char nro_args[NRO_MAX_ARG_BUF];
 static int nro_argc;
 static char *nro_argoffs;
 
-uint64_t nro_start()
+uint64_t nro_start(uint32_t main_handle)
 {
-	uint64_t (*entry)(libtransistor_context_t*) = nro_base + 0x80;
+	uint64_t (*entry)(void*, uint32_t, libtransistor_context_t*) = nro_base + 0x80;
 	uint64_t ret;
 
 	// generate memory block
@@ -69,7 +69,7 @@ uint64_t nro_start()
 	*(void**)(get_tls() + 0x1f8) = NULL;
 
 	// run NRO
-	ret = entry(&loader_context);
+	ret = entry(NULL, main_handle, &loader_context);
 
 	// Restore TLS
 	*tls_userspace_pointer = tls_backup;
@@ -194,7 +194,7 @@ result_t nro_unload()
 	return r;
 }
 
-uint64_t nro_execute(void *load_base, int in_size)
+uint64_t nro_execute(void *load_base, int in_size, uint32_t main_handle)
 {
 	uint64_t ret;
 	result_t r;
@@ -203,7 +203,7 @@ uint64_t nro_execute(void *load_base, int in_size)
 	if(r)
 		return r;
 
-	ret = nro_start();
+	ret = nro_start(main_handle);
 
 	nro_unload(); // unload can fail; for now not a critical error
 
diff --git a/server.c b/server.c
index 1b1f368..3319715 100644
--- a/server.c
+++ b/server.c
@@ -95,7 +95,7 @@ int server_init()
 	return 0;
 }
 
-void server_loop()
+void server_loop(uint32_t main_handle)
 {
 	struct sockaddr_in client_addr;
 	int ret;
@@ -141,7 +141,7 @@ void server_loop()
 				if(size != heap_size && size != 0xFFFFFFFF)
 				{
 					nro_arg_name("NRO");
-					size = nro_execute(heap_base, (int)(ptr - heap_base));
+					size = nro_execute(heap_base, (int)(ptr - heap_base), main_handle);
 					printf("- NRO returned 0x%016lX\n", size);
 				}
 				continue;