[lcrash/cckernel] FIX: don't depend on undefined behavior + fix typo in addend tables

CMakeLists.txt

@@ -365,7 +365,7 @@ add_custom_command(OUTPUT lindows_c.img
 	COMMAND ${CoreUtils_Mkdir_EXECUTABLE} ARGS lindows_c/Users
 
 	# unmount filesystem
-	COMMAND "umount" ARGS lindows_c
+	COMMAND umount ARGS lindows_c
 
 	DEPENDS 
 		lexecutive lcrash

lcrash/CMakeLists.txt

@@ -8,7 +8,7 @@ lw_project(lcrash
 enable_language(ASM)
 
 lw_add_executable(lcrashkern
-	SOURCES lcrash.c util.c efi/guid.c efi/memmap.c gdb/gdb.c
+	SOURCES main.c util.c lnxboot.c acpi/acpi.c efi/efi.c efi/guid.c efi/memmap.c gdb/gdb.c
 )
 add_executable(lcrashkernld IMPORTED)
 set_property(TARGET lcrashkernld PROPERTY IMPORTED_LOCATION ${CMAKE_CURRENT_SOURCE_DIR}/lcrash.ld)
@@ -17,7 +17,7 @@ set_property(TARGET lcrashkern PROPERTY LINK_DEPENDS
 	$<TARGET_FILE:LindowsCompilerSpec>
 )
 set_property(TARGET lcrashkern PROPERTY LINK_OPTIONS -nostdlib -Wl,-T,${CMAKE_CURRENT_SOURCE_DIR}/lcrash.ld )
-target_compile_options(lcrashkern PRIVATE -ggdb -fpic -pie)
+target_compile_options(lcrashkern PRIVATE -ggdb -fpic -pie -Wall -fanalyzer)
 target_link_options(lcrashkern PRIVATE -fpic -pie)
 
 add_custom_command(
@@ -45,7 +45,7 @@ lw_add_executable(cckernel
 add_executable(cckernelld IMPORTED)
 set_property(TARGET cckernelld PROPERTY IMPORTED_LOCATION ${CMAKE_CURRENT_SOURCE_DIR}/setup/compressed/compressed.ld)
 set_property(TARGET cckernel PROPERTY LINK_OPTIONS -nostdlib -Wl,-T,${CMAKE_CURRENT_SOURCE_DIR}/setup/compressed/compressed.ld)
-target_compile_options(cckernel PRIVATE -ggdb -mno-sse -mno-avx) # disable generating SIMD code since we haven't configured it at this stage of the boot thing
+target_compile_options(cckernel PRIVATE -ggdb -mno-sse -mno-avx -Wall -fanalyzer) # disable generating SIMD code since we haven't configured it at this stage of the boot thing
 set_property(SOURCE setup/compressed/cckernel.S PROPERTY OBJECT_DEPENDS
 	${CMAKE_CURRENT_BINARY_DIR}/lcrashkern.gz
 )

lcrash/acpi/acpi.h

@@ -5,13 +5,28 @@
 struct AcpiRSDP;
 struct AcpiXSDT;
 
+/**
+ * Common ACPI table header
+ */
+struct AcpiSDTHeader {
+	c8  Signature[4];
+	u32 Length;
+	u8  Revision;
+	u8  Checksum;
+	c8  OEMID[6];
+	c8  OEMTableID[6];
+	u32 OEMRevision;
+	u32 CreatorID;
+	u32 CreatorRevision;
+};
+
 /**
  * ACPI Root System Description Pointer
  */
 struct [[gnu::packed]] AcpiRSDP {
-	char             Signature[8];
+	c8               Signature[8];
 	u8               Checksum;
-	char             OEM[6];
+	c8               OEM[6];
 	u8               Revision;
 	[[gnu::deprecated]] // we dont care :>
 	u32              RSDTAddress;
@@ -20,3 +35,24 @@ struct [[gnu::packed]] AcpiRSDP {
 	u8               ExtendedChecksum;
 	u8               Reserved[3];
 };
+
+/**
+ * The table of tables
+ */
+struct AcpiXSDT {
+	struct AcpiSDTHeader Header;
+	
+	/// Pointers to other tables
+	[[gnu::aligned(4)]] 
+	u64 Tables[];
+};
+
+/**
+ * Initialize ACPI code
+ */
+void AcpiInitialize();
+
+/**
+ * Check if ACPI is present
+ */
+bool AcpiPresent();

lcrash/efi/memmap.c

@@ -15,19 +15,23 @@ void EfiLoadStoredMemoryMap(
 }
 
 /**
- * Translate a pointer using what we can recover from the UEFI memory map, may return something invalid.
+ * Translate a pointer using what we can recover from the UEFI memory map, returns 0 if not found
  */
 void* EfiTranslatePointer(void* FirmwarePointer) {
+	void* CurrentEntry = (void*)StoredMemoryMap;
+	
 	// Scan the memory map for where our thing is
 	for (int i = 0; i < StoredMemoryMapEntryCount; i++) {
-		struct EfiMemoryDescription* Entry = (struct EfiMemoryDescription*)((void*)StoredMemoryMap + i * StoredMemoryMapEntrySize);
+		struct EfiMemoryDescription* Entry = (struct EfiMemoryDescription*)CurrentEntry;
 
 		if (FirmwarePointer >= Entry->VirtualStart &&
 		    FirmwarePointer <  Entry->VirtualStart + 0x1000 * Entry->NumberOfPages) {
 			return FirmwarePointer - Entry->VirtualStart + Entry->PhysicalStart;
 		}
+
+		CurrentEntry += StoredMemoryMapEntrySize;
 	}
 
 	// Well, we tried
-	return -1;
+	return 0;
 }

lcrash/efi/types.h

@@ -14,6 +14,7 @@ typedef c16  EfiChar16;
 
 typedef EfiVoid* EfiHandle;
 
+#define EFI_SIZEOF_GUID 16
 typedef struct _EfiGuid {
 	u32 data1;
 	u16 data2;

lcrash/gdb/autorun.py

@@ -27,4 +27,5 @@ def add_pretty_printer(name, printer, custom_lookup = None):
 
 add_pretty_printer("_EfiGuid", EfiGuidPrinter, lambda val: EfiGuidPrinter(val) if val.type.strip_typedefs().tag == "_EfiGuid" else None);
 
-# ---  ---
+# --- code ---
+# def transition_cckernel():

lcrash/lcrash.c

@@ -61,7 +61,7 @@ void Panic(const char* message) {
 	Hang();
 }
 
-void entry64() {
+void entry64(struct boot_params* boot_params) {
 	while (1) {};
 
 	Panic("HELLO WORLD.");

lcrash/lnxboot.h

@@ -131,7 +131,7 @@ struct [[gnu::packed]] boot_params {
 	u8                    reserved0[0x4];
 	void*                 tboot_addr;
 	struct ist_info       ist_info;
-	struct acpi_rsdp*     acpi_rsdp_addr;
+	struct AcpiRSDP*      acpi_rsdp_addr;
 	u8                    reserved1[0x8];
 	u8                    hd0_info[0x10];
 	u8                    hd1_info[0x10];
@@ -162,3 +162,13 @@ struct [[gnu::packed]] boot_params {
 	u8                    reserved5[0x30];
 	u8                    eddbuf[0x1ec];
 };
+
+/**
+ * Setup info provided by cckernel
+ */
+extern struct setup_info* BootSetupInfo;
+
+/**
+ * Boot params provided by cckernel
+ */
+extern struct boot_params* BootBootParams;

lcrash/setup/compressed/elf.c

@@ -1,7 +1,49 @@
 #include "elf.h"
 
-int ElfExecute(void* Binary, void* LoadAddr) {
+extern void* memset(void* dest, int ch, uptr count);
+extern void* memcpy(void* dest, const void* src, uptr count);
+
+[[noreturn]]
+void ElfExecute(void* Binary, void* LoadAddr, struct boot_params* BootParams) {
+	struct Elf64_Ehdr* ElfHeader = (struct Elf64_Ehdr*)Binary;
+
+	// Here we would check if we have a valid elf binary
+	// unfortunately, we would have no way to notify the
+	// user, so we'll just pray it is
 	
+	// Hopefully we have progtam headers
+	void* ProgramHeaders = Binary + ElfHeader->e_phoff;
+
+	// Load everything into memory
+	for (int i = 0; i < ElfHeader->e_phnum; i++) {
+		struct Elf64_Phdr* ProgramHeader = (struct Elf64_Phdr*)ProgramHeaders;
+		
+		// Only load loadable segments
+		if (ProgramHeader->p_type == PT_LOAD) {
+			void* FileStart = Binary + ProgramHeader->p_offset;
+			void* LoadStart = LoadAddr + ProgramHeader->p_vaddr;
+
+			uptr LoadSize = ProgramHeader->p_memsz;
+			if (LoadSize > ProgramHeader->p_filesz) LoadSize = ProgramHeader->p_filesz;
+
+			memset(LoadStart, 0, ProgramHeader->p_memsz);
+			memcpy(LoadStart, FileStart, LoadSize);
+		}
+
+		ProgramHeaders += ElfHeader->e_phentsize;
+	}
+
+	// Collect entry point
+	[[noreturn]] void fake_dont_call(struct boot_params*); // stupid hack
+	typeof(fake_dont_call)* KernelEntry = LoadAddr + ElfHeader->e_entry;
 	
-	while (1) {}
+	// Set boot parameters
+	struct setup_info* SetupInfo = (void*)BootParams + 0x1f1;
+	SetupInfo->code32_start = LoadAddr;
+
+	// Enter the kernel
+	KernelEntry(BootParams);
+
+	// we shouldnt ever end up here	
+	__builtin_unreachable();
 }

lcrash/setup/compressed/elf.h

@@ -1,9 +1,18 @@
 #pragma once
 
 #include "../../types.h"
+#include "../../lnxboot.h"
 
-[[packed]]
+#define PT_NULL    0
-struct Elf64_Ehdr {
+#define PT_LOAD    1
+#define PT_DYNAMIC 2
+#define PT_INTERP  3
+#define PT_NOTE    4
+#define PT_SHLIB   5
+#define PT_PHDR    6
+#define PT_TLS     7
+
+struct [[gnu::packed]] Elf64_Ehdr {
 	c8  e_ident[16];
 	u16 e_type;
 	u16 e_machine;
@@ -20,8 +29,7 @@ struct Elf64_Ehdr {
 	u16 e_shstrndx;
 };
 
-[[packed]]
+struct [[gnu::packed]] Elf64_Phdr {
-struct Elf64_Phdr {
 	u32 p_type;
 	u32 p_flags;
 	u64 p_offset;
@@ -33,4 +41,4 @@ struct Elf64_Phdr {
 };
 
 /// We don't have space to allocate memory, so we have no idea where we can pass back ELF state, we'll have to do this all at once
-int ElfExecute(void* Binary, void* LoadAddr);
+void ElfExecute(void* Binary, void* LoadAddr, struct boot_params*);

lcrash/setup/compressed/gzip.c

@@ -33,7 +33,7 @@ void GzipPopulateTable(
 	// Fill in the table in a horribly inefficient manner
 	Code = 0;
 	for (u32 Bits = 0; Bits < 15; Bits++) {
-		const uptr OutputMask = ~(-1 << Bits);
+		const uptr OutputMask = ~((uptr)-1 << Bits);
 		for (int i = 0; i < CodeCounts[Bits]; i++) {
 			// Take the next symbol
 			Code = NextSym[Bits];
@@ -93,7 +93,7 @@ uptr GzipDecompress(c8* Input, uptr InputSize, c8* Output) {
 
 	const u32 DistanceAddends[30] = {
         	1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193, 257, 385, 513, 769, 1025,
-        	1537, 2049, 3073, 40097, 6145, 8193, 12289, 15385, 24577
+        	1537, 2049, 3073, 4097, 6145, 8193, 12289, 16385, 24577
 	};
 
 	void* Location    = (void*)Input;

lcrash/setup/compressed/main.c

@@ -23,7 +23,7 @@ void ccmain(void* imgbase, struct boot_params* boot_params) {
 	uptr BinaryLength = GzipDecompress(cckernel, (u8*)&_CC_ecckernel - (u8*)&_CC_cckernel, kernel_load_addr);
 
 	// start the kernel
-	ElfExecute(kernel_load_addr, kernel_load_addr + BinaryLength + 0x1000 - BinaryLength % 0x1000);
+	ElfExecute(kernel_load_addr, kernel_load_addr + BinaryLength + 0x1000 - BinaryLength % 0x1000, boot_params);
 
 	// we fucked up
 	while (1) {}

lcrash/setup/compressed/mem.S

@@ -1,9 +1,16 @@
 	/// File with support code for gcc memory stuff
 	.section ".text", "ax"
-	.globl   memset
+	.globl memset
 memset:
 	mov %rdx, %rcx
 	mov %sil, %al
 	rep stosb (%rdi)
 	mov %rdi, %rax
 	ret
+
+	.globl memcpy
+memcpy:
+	mov %rdx, %rcx
+	rep movsb (%rsi), (%rdi)
+	mov %rdi, %rax
+	ret

lcrash/util.c

@@ -1,9 +1,9 @@
 #include "util.h"
 #include "types.h"
 
-bool CompareMemory(void* Addr1, void* Addr2, uptr Length) {
+bool CompareMemory(const void* Addr1, const void* Addr2, u32 Length) {
-	u8* Data1 = Addr1;
+	const u8* Data1 = Addr1;
-	u8* Data2 = Addr2;
+	const u8* Data2 = Addr2;
 
 	for (uptr i = 0; i < Length; i++) {
 		if (Data1[i] != Data2[i]) return false;

lcrash/util.h

@@ -5,4 +5,4 @@
 /**
  * Compare the data at two memory addresses
  */
-bool CompareMemory(void* Addr1, void* Addr2, uptr Length);
+bool CompareMemory(const void* Addr1, const void* Addr2, u32 Length);