*/
#define DEBUG 0
-#include <common.h>
+#include <acess.h>
#include <syscalls.h>
#include <proc.h>
#include <errno.h>
+#define CHECK_NUM_NULLOK(v,size) \
+ if((v)&&!Syscall_Valid((size),(Uint)(v))){ret=-1;err=-EINVAL;break;}
+#define CHECK_STR_NULLOK(v) \
+ if((v)&&!Syscall_ValidString((Uint)(v))){ret=-1;err=-EINVAL;break;}
+#define CHECK_NUM_NONULL(v,size) \
+ if(!(v)||!Syscall_Valid((size),(Uint)(v))){ret=-1;err=-EINVAL;break;}
+#define CHECK_STR_NONULL(v) \
+ if(!(v)||!Syscall_ValidString((Uint)(v))){ret=-1;err=-EINVAL;break;}
+
// === IMPORTS ===
extern int Proc_Clone(Uint *Err, Uint Flags);
extern int Threads_WaitTID(int TID, int *status);
extern int Proc_GetMessage(Uint *Err, Uint *Source, void *Buffer);
extern int Proc_Execve(char *File, char **ArgV, char **EnvP);
extern Uint Binary_Load(char *file, Uint *entryPoint);
-extern int VFS_FInfo(int FD, void *Dest, int MaxACLs);
extern int Threads_SetName(char *NewName);
extern int Threads_GetPID();
extern int Threads_GetTID();
-extern int Threads_GetUID();
-extern int Threads_GetGID();
+extern tUID Threads_GetUID();
+extern int Threads_SetUID(Uint *errno, tUID ID);
+extern tGID Threads_GetGID();
+extern int Threads_SetGID(Uint *errno, tGID ID);
+extern int Threads_SetFaultHandler(Uint Handler);
+
+// === PROTOTYPES ===
+ int Syscall_ValidString(Uint Addr);
+ int Syscall_Valid(int Size, Uint Addr);
// === CODE ===
+// TODO: Do sanity checking on arguments, ATM the user can really fuck with the kernel
void SyscallHandler(tSyscallRegs *Regs)
{
Uint64 ret = 0;
- Uint err = 0;
- #if DEBUG
- ENTER("iThread iNum", gCurrentThread->TID, Regs->Num);
+ Uint err = -EOK;
+
+ ENTER("iThread iNum", Threads_GetTID(), Regs->Num);
if(Regs->Num < NUM_SYSCALLS)
LOG("Syscall %s", cSYSCALL_NAMES[Regs->Num]);
- LOG("Arg1: 0x%x, Arg2: 0x%x, Arg3: 0x%x", Regs->Arg1, Regs->Arg2, Regs->Arg3);
- #endif
+ LOG("Arg1: 0x%x, Arg2: 0x%x, Arg3: 0x%x, Arg4: 0x%x", Regs->Arg1, Regs->Arg2, Regs->Arg3, Regs->Arg4);
+
switch(Regs->Num)
{
// -- Exit the current thread
- case SYS_EXIT: Threads_Exit(); break;
+ case SYS_EXIT: Threads_Exit(0, Regs->Arg1); break;
// -- Put the current thread to sleep
case SYS_SLEEP: Threads_Sleep(); break;
// -- Yield current timeslice
case SYS_YIELD: Threads_Yield(); break;
+ // -- Set Error Handler
+ case SYS_SETFAULTHANDLER:
+ Threads_SetFaultHandler(Regs->Arg1);
+ break;
+
// -- Clone the current thread
case SYS_CLONE:
// Call clone system call
ret = Proc_Clone(&err, Regs->Arg1);
- // Change user stack if requested
+ // Change user stack if a new stack address is passed
if(ret == 0 && Regs->Arg2)
Regs->StackPointer = Regs->Arg2;
break;
// -- Wait for a thread
case SYS_WAITTID:
+ // Sanity Check (Status can be NULL)
+ CHECK_NUM_NULLOK( Regs->Arg2, sizeof(int) );
+ // TID, *Status
ret = Threads_WaitTID(Regs->Arg1, (void*)Regs->Arg2);
break;
case SYS_GETUID: ret = Threads_GetUID(); break;
case SYS_GETGID: ret = Threads_GetGID(); break;
+ // -- Set User/Group IDs
+ case SYS_SETUID: ret = Threads_SetUID(&err, Regs->Arg1); break;
+ case SYS_SETGID: ret = Threads_SetGID(&err, Regs->Arg1); break;
+
// -- Send Message
case SYS_SENDMSG:
+ CHECK_NUM_NONULL(Regs->Arg3, Regs->Arg2);
+ // Destination, Size, *Data
ret = Proc_SendMessage(&err, Regs->Arg1, Regs->Arg2, (void*)Regs->Arg3);
break;
// -- Check for messages
case SYS_GETMSG:
+ CHECK_NUM_NULLOK(Regs->Arg1, sizeof(Uint));
+ if( Regs->Arg2 && Regs->Arg2 != -1 && !MM_IsUser(Regs->Arg2) )
+ {
+ err = -EINVAL; ret = -1; break;
+ }
+ // *Source, *Data
ret = Proc_GetMessage(&err, (Uint*)Regs->Arg1, (void*)Regs->Arg2);
break;
// -- Set the thread's name
case SYS_SETNAME:
- // Sanity Check
- if(!Regs->Arg1) { ret = -1; err = -EINVAL; break; }
- Threads_SetName( (void*)Regs->Arg1 );
+ CHECK_STR_NONULL(Regs->Arg1);
+ Threads_SetName( (char*)Regs->Arg1 );
break;
// ---
// Binary Control
// ---
case SYS_EXECVE:
+ CHECK_STR_NONULL(Regs->Arg1);
+ //Log(" Regs = {Arg2: %x, Arg3: %x}", Regs->Arg2, Regs->Arg3);
+ {
+ int i;
+ char **tmp = (char**)Regs->Arg2;
+ // Check ArgV (traverse array checking all string pointers)
+ CHECK_NUM_NONULL( tmp, sizeof(char**) );
+ //Log("tmp = %p", tmp);
+ for(i=0;tmp[i];i++) {
+ CHECK_NUM_NONULL( &tmp[i], sizeof(char*) );
+ CHECK_STR_NONULL( tmp[i] );
+ }
+ // Check EnvP also
+ // - EnvP can be NULL
+ if( Regs->Arg3 )
+ {
+ tmp = (char**)Regs->Arg3;
+ //Log("tmp = %p", tmp);
+ for(i=0;tmp[i];i++) {
+ CHECK_NUM_NULLOK( &tmp[i], sizeof(char*) );
+ CHECK_STR_NONULL( tmp[i] );
+ }
+ }
+ }
+ LEAVE('s', "Assuming 0");
+ // Path, **Argv, **Envp
ret = Proc_Execve((char*)Regs->Arg1, (char**)Regs->Arg2, (char**)Regs->Arg3);
break;
case SYS_LOADBIN:
+ if( !Syscall_ValidString(Regs->Arg1)
+ || !Syscall_Valid(sizeof(Uint), Regs->Arg2) ) {
+ err = -EINVAL;
+ ret = 0;
+ break;
+ }
+ // Path, *Entrypoint
ret = Binary_Load((char*)Regs->Arg1, (Uint*)Regs->Arg2);
break;
// Virtual Filesystem
// ---
case SYS_OPEN:
+ if( !Syscall_ValidString(Regs->Arg1) ) {
+ err = -EINVAL;
+ ret = -1;
+ break;
+ }
ret = VFS_Open((char*)Regs->Arg1, Regs->Arg2 | VFS_OPENFLAG_USER);
break;
VFS_Close( Regs->Arg1 );
break;
- case SYS_WRITE:
- #if BITS < 64
- VFS_Write( Regs->Arg1, Regs->Arg2|((Uint64)Regs->Arg3<<32), (void*)Regs->Arg4 );
+ case SYS_SEEK:
+ #if BITS == 64
+ ret = VFS_Seek( Regs->Arg1, Regs->Arg2, Regs->Arg3 );
#else
- VFS_Write( Regs->Arg1, Regs->Arg2, (void*)Regs->Arg3 );
+ ret = VFS_Seek( Regs->Arg1, Regs->Arg2|((Uint64)Regs->Arg3<<64), Regs->Arg4 );
#endif
break;
+
+ case SYS_TELL:
+ ret = VFS_Tell( Regs->Arg1 );
+ break;
+
+ case SYS_WRITE:
+ CHECK_NUM_NONULL( Regs->Arg3, Regs->Arg2 );
+ ret = VFS_Write( Regs->Arg1, Regs->Arg2, (void*)Regs->Arg3 );
+ break;
case SYS_READ:
- #if BITS < 64
- VFS_Read( Regs->Arg1, Regs->Arg2|((Uint64)Regs->Arg3<<32), (void*)Regs->Arg4 );
- #else
- VFS_Read( Regs->Arg1, Regs->Arg2, (void*)Regs->Arg3 );
- #endif
+ CHECK_NUM_NONULL( Regs->Arg3, Regs->Arg2 );
+ ret = VFS_Read( Regs->Arg1, Regs->Arg2, (void*)Regs->Arg3 );
break;
case SYS_FINFO:
+ CHECK_NUM_NONULL( Regs->Arg2, sizeof(tFInfo) + Regs->Arg3*sizeof(tVFS_ACL) );
+ // FP, Dest, MaxACLs
ret = VFS_FInfo( Regs->Arg1, (void*)Regs->Arg2, Regs->Arg3 );
break;
+ // Get ACL Value
+ case SYS_GETACL:
+ if( !Syscall_Valid(sizeof(tVFS_ACL), Regs->Arg1) ) {
+ err = -EINVAL;
+ ret = -1;
+ break;
+ }
+ ret = VFS_GetACL( Regs->Arg1, (void*)Regs->Arg2 );
+ break;
+
+ // Read Directory
+ case SYS_READDIR:
+ if( !Syscall_Valid(8, Regs->Arg2) ) {
+ err = -EINVAL;
+ ret = -1;
+ break;
+ }
+ ret = VFS_ReadDir( Regs->Arg1, (void*)Regs->Arg2 );
+ break;
+
+ // Open a file that is a entry in an open directory
+ case SYS_OPENCHILD:
+ if( !Syscall_ValidString(Regs->Arg2) ) {
+ err = -EINVAL;
+ ret = -1;
+ break;
+ }
+ ret = VFS_OpenChild( &err, Regs->Arg1, (char*)Regs->Arg2, Regs->Arg3);
+ break;
+
+ // Change Directory
+ case SYS_CHDIR:
+ if( !Syscall_ValidString(Regs->Arg1) ) {
+ err = -EINVAL;
+ ret = -1;
+ break;
+ }
+ ret = VFS_ChDir( (void*)Regs->Arg1 );
+ break;
+
+ // IO Control
+ case SYS_IOCTL:
+ // All sanity checking should be done by the driver
+ ret = VFS_IOCtl( Regs->Arg1, Regs->Arg2, (void*)Regs->Arg3 );
+ break;
+
+ // Mount a filesystem
+ case SYS_MOUNT:
+ // Only root can mount filesystems
+ if(Threads_GetUID() != 0) {
+ err = -EACCES;
+ ret = -1;
+ break;
+ }
+ // Sanity check the paths
+ if(!Syscall_ValidString(Regs->Arg1)
+ || !Syscall_ValidString(Regs->Arg2)
+ || !Syscall_ValidString(Regs->Arg3)
+ || !Syscall_ValidString(Regs->Arg4) ) {
+ err = -EINVAL;
+ ret = -1;
+ break;
+ }
+ ret = VFS_Mount(
+ (char*)Regs->Arg1, // Device
+ (char*)Regs->Arg2, // Mount point
+ (char*)Regs->Arg3, // Filesystem
+ (char*)Regs->Arg4 // Options
+ );
+ break;
+
// -- Debug
+ //#if DEBUG_BUILD
case SYS_DEBUG:
Log((char*)Regs->Arg1,
Regs->Arg2, Regs->Arg3, Regs->Arg4, Regs->Arg5, Regs->Arg6);
break;
+ //#endif
// -- Default (Return Error)
default:
ret = -1;
break;
}
+
+ if(err != 0) {
+ LOG("ID: %i, Return errno = %i", Regs->Num, err);
+ }
+
#if BITS < 64
Regs->Return = ret&0xFFFFFFFF;
Regs->RetHi = ret >> 32;
#endif
Regs->Error = err;
#if DEBUG
- LOG("SyscallHandler: err = %i", err);
- LEAVE('x', ret);
+ LOG("err = %i", err);
+ if(Regs->Num != SYS_EXECVE)
+ LEAVE('x', ret);
+ else
+ LOG("Actual %i", ret);
#endif
}
+/**
+ * \fn int Syscall_ValidString(Uint Addr)
+ * \brief Checks if a memory address contains a valid string
+ */
+int Syscall_ValidString(Uint Addr)
+{
+ // Check if the memory is user memory
+ if(!MM_IsUser(Addr)) return 0;
+
+ return CheckString( (char*)Addr );
+}
+
+/**
+ * \fn int Syscall_Valid(int Size, Uint Addr)
+ * \brief Checks if a memory address is valid
+ */
+int Syscall_Valid(int Size, Uint Addr)
+{
+ if(!MM_IsUser(Addr)) return 0;
+
+ return CheckMem( (void*)Addr, Size );
+}