Made exec syscall relative using app name

My plan is to implement a mobile-OS-like sandboxing using manifests
and permission middlewares. Let's see if I can manage to do this
without sacrificing too much performance.

I'm also wondering whether I should implement open/close syscalls
which would result in a cleaner block/unblock mechanism. I need to
think. Hmmm.. Naa

7 files changed, 22 insertions, 17 deletions

diff --git a/kernel/Makefile b/kernel/Makefile
index 1c37168..e28d2d8 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -31,5 +31,5 @@ all: compile
 	@$(AS) $(ASFLAGS) $< -o $@
 
 compile: $(COBJS)
-	@mkdir -p $(BUILD)/apps/
-	@$(LD) -N -z max-page-size=0x1000 -ekernel_main -Tlink.ld -o $(BUILD)/apps/kernel -L$(BUILD) $+ -lk
+	@mkdir -p $(BUILD)/apps/kernel/
+	@$(LD) -N -z max-page-size=0x1000 -ekernel_main -Tlink.ld -o $(BUILD)/apps/kernel/exec -L$(BUILD) $+ -lk
diff --git a/kernel/drivers/cpu.c b/kernel/drivers/cpu.c
index 86ae2be..f751d33 100644
--- a/kernel/drivers/cpu.c
+++ b/kernel/drivers/cpu.c
@@ -145,7 +145,7 @@ CLEAR void cpu_enable_features(void)
 		panic("No FPU support!\n");
 	}
 
-	// Enable NX (IA32_EFER.NXE)
+	// Enable NX (IA32_EFER.NXE) // TODO: Use NX Bit? (only possible in PAE 64 bit paging?)
 	if (cpu_extended_information.edx & CPUID_EXT_INFO_EDX_NX) {
 		__asm__ volatile("movl $0xc0000080, %ecx\n"
 				 "rdmsr\n"
diff --git a/kernel/features/fs.c b/kernel/features/fs.c
index 47e7891..b5bb2a4 100644
--- a/kernel/features/fs.c
+++ b/kernel/features/fs.c
@@ -565,7 +565,7 @@ static res read_inode(struct ext2_inode *in, void *buf, u32 offset, u32 count, s
 
 static u32 find_inode(const char *name, u32 dir_inode, struct device *dev)
 {
-	if (!dir_inode)
+	if ((signed)dir_inode <= 0)
 		return (unsigned)-1;
 
 	struct ext2_inode i = { 0 };
@@ -624,7 +624,7 @@ static struct ext2_inode *find_inode_by_path(const char *path, struct ext2_inode
 		current_inode = find_inode(path_cp, current_inode, dev);
 		path_cp[i] = '/';
 
-		if (current_inode == 0) {
+		if ((signed)current_inode <= 0) {
 			free(init);
 			return NULL;
 		}
diff --git a/kernel/features/load.c b/kernel/features/load.c
index d87bb94..91954b1 100644
--- a/kernel/features/load.c
+++ b/kernel/features/load.c
@@ -9,11 +9,19 @@
 #include <random.h>
 #include <str.h>
 
-res elf_load(const char *path, struct proc *proc)
+res elf_load(const char *name, struct proc *proc)
 {
-	if (!memory_valid(path))
+	if (!memory_valid(name))
 		return -EFAULT;
 
+	stac();
+	char path[64] = { "/apps/" };
+	strlcat(path, name, sizeof(path));
+	strlcpy(proc->dir, path, sizeof(proc->dir));
+	strlcat(path, "/exec", sizeof(path));
+	strlcpy(proc->name, name, sizeof(proc->name));
+	clac();
+
 	struct stat s = { 0 };
 	memory_bypass_enable();
 	res stat = vfs_stat(path, &s);
@@ -32,10 +40,6 @@ res elf_load(const char *path, struct proc *proc)
 	if (read != sizeof(header))
 		return -ENOEXEC;
 
-	stac();
-	strlcpy(proc->name, path, sizeof(proc->name));
-	clac();
-
 	// Valid?
 	u8 *magic = header.ident;
 	u8 valid_magic = magic[ELF_IDENT_MAG0] == ELF_MAG0 && magic[ELF_IDENT_MAG1] == ELF_MAG1 &&
@@ -86,8 +90,8 @@ res elf_load(const char *path, struct proc *proc)
 		virtual_map(proc->page_dir, prange, vrange.base, MEMORY_CLEAR | MEMORY_USER);
 
 		memory_bypass_enable();
-		if ((u32)vfs_read(proc->name, (void *)((u32)program.vaddr + rand_off),
-				  program.offset, program.filesz) != program.filesz) {
+		if ((u32)vfs_read(path, (void *)((u32)program.vaddr + rand_off), program.offset,
+				  program.filesz) != program.filesz) {
 			memory_bypass_disable();
 			memory_switch_dir(prev);
 			return -ENOEXEC;
diff --git a/kernel/features/proc.c b/kernel/features/proc.c
index f547193..479427c 100644
--- a/kernel/features/proc.c
+++ b/kernel/features/proc.c
@@ -559,7 +559,7 @@ NORETURN void proc_init(void)
 	// Idle proc
 	// TODO: Reimplement hlt privileges in idle proc (SMEP!)
 	struct proc *kernel_proc = proc_make(PROC_PRIV_NONE);
-	assert(elf_load("/bin/idle", kernel_proc) == EOK);
+	assert(elf_load("idle", kernel_proc) == EOK);
 	proc_stack_push(kernel_proc, 0);
 	proc_stack_push(kernel_proc, 0);
 	kernel_proc->state = PROC_BLOCKED;
@@ -570,7 +570,7 @@ NORETURN void proc_init(void)
 
 	// Init proc (root)
 	struct proc *init = proc_make(PROC_PRIV_ROOT);
-	assert(elf_load("/bin/init", init) == EOK);
+	assert(elf_load("init", init) == EOK);
 	proc_stack_push(init, 0);
 	proc_stack_push(init, 0);
 	current = list_first_data(proc_list_running, init);
diff --git a/kernel/inc/load.h b/kernel/inc/load.h
index af59cce..9e62369 100644
--- a/kernel/inc/load.h
+++ b/kernel/inc/load.h
@@ -161,6 +161,6 @@ struct PACKED elf_symbol {
 	u16 shndx;
 };
 
-res elf_load(const char *path, struct proc *proc) NONNULL;
+res elf_load(const char *name, struct proc *proc) NONNULL;
 
 #endif
diff --git a/kernel/inc/proc.h b/kernel/inc/proc.h
index d20a1b0..dcc2eeb 100644
--- a/kernel/inc/proc.h
+++ b/kernel/inc/proc.h
@@ -53,7 +53,8 @@ struct stream {
 struct proc {
 	u32 pid;
 	u32 entry;
-	char name[32];
+	char name[64];
+	char dir[64];
 	struct stream streams[4];
 	struct page_dir *page_dir;
 	struct regs regs;