X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=Kernel%2Fsyscalls.c;h=35e48902566bc1a846a134ebfb7af3d98d88334d;hb=f4e3c3d24ca880fe72396b2b0fc1ca3ce506b6ff;hp=f655707c5ca6571e9978f4cf273b302dcdf0ea3c;hpb=9b65eb6247a9332cf2cc83807e2d558b4337394b;p=tpg%2Facess2.git diff --git a/Kernel/syscalls.c b/Kernel/syscalls.c index f655707c..35e48902 100644 --- a/Kernel/syscalls.c +++ b/Kernel/syscalls.c @@ -4,48 +4,54 @@ */ #define DEBUG 0 -#include +#include #include #include +#include #include +#include + +#define CHECK_NUM_NULLOK(v,size) \ + if((v)&&!Syscall_Valid((size),(v))){ret=-1;err=-EINVAL;break;} +#define CHECK_STR_NULLOK(v) \ + if((v)&&!Syscall_ValidString((v))){ret=-1;err=-EINVAL;break;} +#define CHECK_NUM_NONULL(v,size) \ + if(!(v)||!Syscall_Valid((size),(v))){ret=-1;err=-EINVAL;break;} +#define CHECK_STR_NONULL(v) \ + if(!(v)||!Syscall_ValidString((v))){ret=-1;err=-EINVAL;break;} // === IMPORTS === -extern int Proc_Clone(Uint *Err, Uint Flags); -extern int Threads_WaitTID(int TID, int *status); -extern Uint Proc_SendMessage(Uint *Err, Uint Dest, Uint Length, void *Data); -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(); +extern Uint Binary_Load(const char *file, Uint *entryPoint); // === PROTOTYPES === - int Syscall_ValidString(Uint Addr); - int Syscall_Valid(int Size, Uint Addr); +void SyscallHandler(tSyscallRegs *Regs); + int Syscall_ValidString(const char *Addr); + int Syscall_Valid(int Size, const void *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", 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); + Uint err = -EOK; + int callNum = Regs->Num; + + #if DEBUG < 2 + if(callNum != SYS_READ && callNum != SYS_WRITE) { + #endif + ENTER("iThread iNum", Threads_GetTID(), callNum); + if(callNum < NUM_SYSCALLS) + LOG("Syscall %s", cSYSCALL_NAMES[callNum]); + LOG("Arg1: 0x%x, Arg2: 0x%x, Arg3: 0x%x, Arg4: 0x%x", Regs->Arg1, Regs->Arg2, Regs->Arg3, Regs->Arg4); + #if DEBUG < 2 + } #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; @@ -53,13 +59,15 @@ void SyscallHandler(tSyscallRegs *Regs) // -- 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 - if(ret == 0 && !(Regs->Arg1 & CLONE_VM)) - Regs->StackPointer = Regs->Arg2; + ret = Proc_Clone(Regs->Arg1); break; // -- Send a signal @@ -70,7 +78,10 @@ void SyscallHandler(tSyscallRegs *Regs) // -- Wait for a thread case SYS_WAITTID: - ret = Threads_WaitTID(Regs->Arg1, (void*)Regs->Arg2); + // Sanity Check (Status can be NULL) + CHECK_NUM_NULLOK( (int*)Regs->Arg2, sizeof(int) ); + // TID, *Status + ret = Threads_WaitTID(Regs->Arg1, (int*)Regs->Arg2); break; // -- Get the physical address of a page @@ -95,29 +106,83 @@ 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: 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( (void*)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( (Uint*)Regs->Arg1, sizeof(Uint) ); + // NOTE: Can't do range checking as we don't know the size + // - Should be done by Proc_GetMessage + 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; + // -- Get the current timestamp + case SYS_GETTIME: + ret = now(); + 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( (char*) Regs->Arg1); + Threads_SetName( (char*)Regs->Arg1 ); break; // --- // Binary Control // --- + // -- Replace the current process with another case SYS_EXECVE: - ret = Proc_Execve((char*)Regs->Arg1, (char**)Regs->Arg2, (char**)Regs->Arg3); + CHECK_STR_NONULL((char*)Regs->Arg1); + // Check the argument arrays + { + 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] ); + } + if(ret == -1) break; + // Check EnvP also + // - EnvP can be NULL + if( Regs->Arg3 ) + { + tmp = (char**)Regs->Arg3; + CHECK_NUM_NONULL(tmp, sizeof(char**)); + for(i=0;tmp[i];i++) { + CHECK_NUM_NONULL( &tmp[i], sizeof(char*) ); + CHECK_STR_NONULL( tmp[i] ); + } + if(ret == -1) break; + } + } + LEAVE('s', "Assuming 0"); + // Path, **Argv, **Envp + ret = Proc_Execve( (char*)Regs->Arg1, (char**)Regs->Arg2, (char**)Regs->Arg3 ); break; + // -- Load a binary into the current process case SYS_LOADBIN: + if( !Syscall_ValidString( (char*) Regs->Arg1) + || !Syscall_Valid(sizeof(Uint), (Uint*)Regs->Arg2) ) { + err = -EINVAL; + ret = 0; + break; + } + // Path, *Entrypoint ret = Binary_Load((char*)Regs->Arg1, (Uint*)Regs->Arg2); break; @@ -125,78 +190,154 @@ void SyscallHandler(tSyscallRegs *Regs) // Virtual Filesystem // --- case SYS_OPEN: + CHECK_STR_NONULL( (char*)Regs->Arg1 ); + LOG("VFS_Open(\"%s\", 0x%x)", (char*)Regs->Arg1, Regs->Arg2 | VFS_OPENFLAG_USER); ret = VFS_Open((char*)Regs->Arg1, Regs->Arg2 | VFS_OPENFLAG_USER); break; case SYS_CLOSE: + LOG("VFS_Close(%i)", Regs->Arg1); 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)<<32), Regs->Arg4 ); #endif break; + + case SYS_TELL: + ret = VFS_Tell( Regs->Arg1 ); + break; + + case SYS_WRITE: + CHECK_NUM_NONULL( (void*)Regs->Arg2, Regs->Arg3 ); + ret = VFS_Write( Regs->Arg1, Regs->Arg3, (void*)Regs->Arg2 ); + 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( (void*)Regs->Arg2, Regs->Arg3 ); + ret = VFS_Read( Regs->Arg1, Regs->Arg3, (void*)Regs->Arg2 ); break; case SYS_FINFO: + CHECK_NUM_NONULL( (void*)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(8, Regs->Arg1) ) { - err = -EINVAL; - ret = -1; - break; - } + CHECK_NUM_NONULL( (void*)Regs->Arg2, sizeof(tVFS_ACL) ); ret = VFS_GetACL( Regs->Arg1, (void*)Regs->Arg2 ); break; // Read Directory case SYS_READDIR: - if( !Syscall_ValidString(Regs->Arg2) ) { - err = -EINVAL; - ret = -1; - break; - } + // TODO: What if the filename is longer? + // Maybe force it to be a 256 byte buffer + CHECK_NUM_NONULL( (void*)Regs->Arg2, 256 ); ret = VFS_ReadDir( Regs->Arg1, (void*)Regs->Arg2 ); break; + // Open a file that is a entry in an open directory + case SYS_OPENCHILD: + CHECK_STR_NONULL( (char*)Regs->Arg2 ); + ret = VFS_OpenChild( Regs->Arg1, (char*)Regs->Arg2, Regs->Arg3); + break; + // Change Directory case SYS_CHDIR: - if( !Syscall_ValidString(Regs->Arg1) ) { + CHECK_STR_NONULL( (const char*)Regs->Arg1 ); + ret = VFS_ChDir( (const char*)Regs->Arg1 ); + break; + + // IO Control + case SYS_IOCTL: + // All sanity checking should be done by the driver + if( Regs->Arg3 && !MM_IsUser(Regs->Arg3) ) { + err = -EINVAL; ret = -1; break; + } + 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((char*)Regs->Arg1) + || !Syscall_ValidString((char*)Regs->Arg2) + || !Syscall_ValidString((char*)Regs->Arg3) + || !Syscall_ValidString((char*)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; + + // Wait on a set of handles + case SYS_SELECT: + // Sanity checks + if( (Regs->Arg2 && !Syscall_Valid(sizeof(fd_set), (void*)Regs->Arg2)) + || (Regs->Arg3 && !Syscall_Valid(sizeof(fd_set), (void*)Regs->Arg3)) + || (Regs->Arg4 && !Syscall_Valid(sizeof(fd_set), (void*)Regs->Arg4)) + || (Regs->Arg5 && !Syscall_Valid(sizeof(tTime), (void*)Regs->Arg5)) ) + { err = -EINVAL; ret = -1; break; } - ret = VFS_ChDir( (void*)Regs->Arg1 ); + // Perform the call + ret = VFS_Select( + Regs->Arg1, // Max handle + (fd_set *)Regs->Arg2, // Read + (fd_set *)Regs->Arg3, // Write + (fd_set *)Regs->Arg4, // Errors + (tTime *)Regs->Arg5, // Timeout + 0 // User handles + ); break; // -- Debug + //#if DEBUG_BUILD case SYS_DEBUG: - Log((char*)Regs->Arg1, + CHECK_STR_NONULL( (char*)Regs->Arg1 ); + LogF("Log: %08lli [%i] ", now(), Threads_GetTID()); + LogF((const char*)Regs->Arg1, Regs->Arg2, Regs->Arg3, Regs->Arg4, Regs->Arg5, Regs->Arg6); + LogF("\r\n"); break; + //#endif // -- Default (Return Error) default: - Warning("SyscallHandler: Unknown System Call %i", Regs->Num); + Log_Warning("Syscalls", "Unknown System Call %i", Regs->Num); if(Regs->Num < NUM_SYSCALLS) - Warning(" Syscall '%s'", cSYSCALL_NAMES[Regs->Num]); + Log_Warning("Syscall", " named '%s'", cSYSCALL_NAMES[Regs->Num]); err = -ENOSYS; ret = -1; break; } + + if(err == 0) err = errno; + + if(err != 0) { + LOG("ID: %i, Return errno = %i", Regs->Num, err); + } + #if BITS < 64 Regs->Return = ret&0xFFFFFFFF; Regs->RetHi = ret >> 32; @@ -205,41 +346,39 @@ void SyscallHandler(tSyscallRegs *Regs) #endif Regs->Error = err; #if DEBUG - LOG("SyscallHandler: err = %i", err); - LEAVE('x', ret); + # if DEBUG < 2 + if( callNum != SYS_READ && callNum != SYS_WRITE ) { + # endif + LOG("err = %i", err); + if( callNum == SYS_EXECVE ) + LOG("Actual %i", ret); + else + LEAVE('x', ret); + # if DEBUG < 2 + } + # endif #endif } /** - * \fn int Syscall_ValidString(Uint Addr) + * \fn int Syscall_ValidString(const char *Addr) * \brief Checks if a memory address contains a valid string */ -int Syscall_ValidString(Uint Addr) +int Syscall_ValidString(const char *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 ++; - } + // Check if the memory is user memory + if(!MM_IsUser( (tVAddr) Addr)) return 0; - return 1; + return CheckString( Addr ); } /** - * \fn int Syscall_Valid(int Size, Uint Addr) + * \fn int Syscall_Valid(int Size, const void *Addr) * \brief Checks if a memory address is valid */ -int Syscall_Valid(int Size, Uint Addr) +int Syscall_Valid(int Size, const void *Addr) { - while(Size--) - { - if(!MM_GetPhysAddr(Addr)) return 0; - Addr ++; - } - return 1; + if(!MM_IsUser( (tVAddr)Addr )) return 0; + + return CheckMem( Addr, Size ); }