X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=Kernel%2Fsyscalls.c;h=8d17e74d2120967ba5d058f1b7ec0111cff17679;hb=b6c3b3cf61caafbd91bbf3acc81995e472656a5b;hp=8790be767e6c4d365b7cd65f923408bb66ed70b2;hpb=72fcc8d0873e91f713be3d23af32a4e83f40cdf5;p=tpg%2Facess2.git diff --git a/Kernel/syscalls.c b/Kernel/syscalls.c index 8790be76..8d17e74d 100644 --- a/Kernel/syscalls.c +++ b/Kernel/syscalls.c @@ -17,27 +17,35 @@ 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 VFS_GetACL(int FD, void *Dest); +extern int VFS_ChDir(char *Dest); extern int Threads_SetName(char *NewName); extern int Threads_GetPID(); extern int Threads_GetTID(); extern int Threads_GetUID(); extern int Threads_GetGID(); +// === 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); + 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 + 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; @@ -49,7 +57,7 @@ void SyscallHandler(tSyscallRegs *Regs) 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; @@ -87,6 +95,10 @@ void SyscallHandler(tSyscallRegs *Regs) case SYS_GETUID: ret = Threads_GetUID(); break; case SYS_GETGID: ret = Threads_GetGID(); break; + // -- Set User/Group IDs + case SYS_SETUID: Log("Setting User ID to %i", Regs->Arg1); break; + case SYS_SETGID: Log("Setting Group ID to %i", Regs->Arg1); break; + // -- Send Message case SYS_SENDMSG: ret = Proc_SendMessage(&err, Regs->Arg1, Regs->Arg2, (void*)Regs->Arg3); @@ -107,9 +119,20 @@ void SyscallHandler(tSyscallRegs *Regs) // Binary Control // --- case SYS_EXECVE: + if( !Syscall_ValidString(Regs->Arg1) ) { + err = -EINVAL; + ret = -1; + break; + } 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 = -1; + break; + } ret = Binary_Load((char*)Regs->Arg1, (Uint*)Regs->Arg2); break; @@ -117,6 +140,11 @@ void SyscallHandler(tSyscallRegs *Regs) // 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; @@ -124,30 +152,94 @@ void SyscallHandler(tSyscallRegs *Regs) VFS_Close( Regs->Arg1 ); break; + case SYS_SEEK: + ret = VFS_Seek( Regs->Arg1, Regs->Arg2, Regs->Arg3); + break; + + case SYS_TELL: + ret = VFS_Tell( Regs->Arg1 ); + break; + case SYS_WRITE: #if BITS < 64 - VFS_Write( Regs->Arg1, Regs->Arg2|((Uint64)Regs->Arg3<<32), (void*)Regs->Arg4 ); + ret = VFS_Write( Regs->Arg1, Regs->Arg2|((Uint64)Regs->Arg3<<32), (void*)Regs->Arg4 ); #else - VFS_Write( Regs->Arg1, Regs->Arg2, (void*)Regs->Arg3 ); + ret = VFS_Write( Regs->Arg1, Regs->Arg2, (void*)Regs->Arg3 ); #endif break; case SYS_READ: #if BITS < 64 - VFS_Read( Regs->Arg1, Regs->Arg2|((Uint64)Regs->Arg3<<32), (void*)Regs->Arg4 ); + ret = VFS_Read( Regs->Arg1, Regs->Arg2|((Uint64)Regs->Arg3<<32), (void*)Regs->Arg4 ); #else - VFS_Read( Regs->Arg1, Regs->Arg2, (void*)Regs->Arg3 ); + ret = VFS_Read( Regs->Arg1, Regs->Arg2, (void*)Regs->Arg3 ); #endif break; case SYS_FINFO: ret = VFS_FInfo( Regs->Arg1, (void*)Regs->Arg2, Regs->Arg3 ); break; - + + // Get ACL Value + case SYS_GETACL: + if( !Syscall_Valid(8, Regs->Arg1) ) { + err = -EINVAL; + ret = -1; + break; + } + ret = VFS_GetACL( Regs->Arg1, (void*)Regs->Arg2 ); + break; + + // Read Directory case SYS_READDIR: + if( !Syscall_ValidString(Regs->Arg2) ) { + err = -EINVAL; + ret = -1; + break; + } ret = VFS_ReadDir( Regs->Arg1, (void*)Regs->Arg2 ); 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: + 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 case SYS_DEBUG: Log((char*)Regs->Arg1, @@ -176,3 +268,36 @@ void SyscallHandler(tSyscallRegs *Regs) #endif } +/** + * \fn int Syscall_ValidString(Uint Addr) + * \brief Checks if a memory address contains a valid string + */ +int Syscall_ValidString(Uint Addr) +{ + // Check 1st page + if(!MM_GetPhysAddr(Addr)) return 0; + + // Traverse String + while(*(char*)Addr) + { + if(!MM_GetPhysAddr(Addr)) return 0; + // Increment string pointer + Addr ++; + } + + return 1; +} + +/** + * \fn int Syscall_Valid(int Size, Uint Addr) + * \brief Checks if a memory address is valid + */ +int Syscall_Valid(int Size, Uint Addr) +{ + while(Size--) + { + if(!MM_GetPhysAddr(Addr)) return 0; + Addr ++; + } + return 1; +}