X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=Kernel%2Fsyscalls.c;h=1294b21413286bc5cc1d01b55366534550fd05c5;hb=d7d0479311c4dba418ee880f27f01418fd536344;hp=ddcdfa2d4c145324a5a35111d73ac53a6e63c96f;hpb=c90736022b1f62a99b15c8613aa7e3f514e01fc9;p=tpg%2Facess2.git diff --git a/Kernel/syscalls.c b/Kernel/syscalls.c index ddcdfa2d..1294b214 100644 --- a/Kernel/syscalls.c +++ b/Kernel/syscalls.c @@ -4,45 +4,70 @@ */ #define DEBUG 0 -#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 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 Uint Binary_Load(const char *file, Uint *entryPoint); + +// === PROTOTYPES === +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", gCurrentThread->TID, 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: Proc_Exit(); break; + case SYS_EXIT: Threads_Exit(0, Regs->Arg1); break; // -- Put the current thread to sleep - case SYS_SLEEP: Proc_Sleep(); Log(" SyscallHandler: %i is alive", gCurrentThread->TID); break; + case SYS_SLEEP: Threads_Sleep(); break; // -- Yield current timeslice - case SYS_YIELD: Proc_Yield(); break; + 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; @@ -53,55 +78,111 @@ void SyscallHandler(tSyscallRegs *Regs) ret = -1; break; + // -- Wait for a thread + case SYS_WAITTID: + // 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 case SYS_GETPHYS: ret = MM_GetPhysAddr(Regs->Arg1); break; + // -- Map an address case SYS_MAP: MM_Map(Regs->Arg1, Regs->Arg2); break; + // -- Allocate an address case SYS_ALLOCATE: ret = MM_Allocate(Regs->Arg1); break; + // -- Unmap an address case SYS_UNMAP: MM_Deallocate(Regs->Arg1); break; // -- Get Thread/Process IDs - case SYS_GETTID: ret = gCurrentThread->TID; break; - case SYS_GETPID: ret = gCurrentThread->TGID; break; + case SYS_GETTID: ret = Threads_GetTID(); break; + case SYS_GETPID: ret = Threads_GetPID(); break; + // -- Get User/Group IDs - case SYS_GETUID: ret = gCurrentThread->UID; break; - case SYS_GETGID: ret = gCurrentThread->GID; 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( (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; } - // Lock Process - LOCK( &gCurrentThread->IsLocked ); - // Free old name - if(gCurrentThread->ThreadName && (Uint)gCurrentThread->ThreadName > 0xE0800000) - free(gCurrentThread->ThreadName); - // Change name - gCurrentThread->ThreadName = malloc( strlen( (char*)Regs->Arg1 ) + 1 ); - strcpy(gCurrentThread->ThreadName, (char*)Regs->Arg1); - // Unlock - RELEASE( &gCurrentThread->IsLocked ); + 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] ); + } + // 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; + // -- 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; @@ -109,45 +190,153 @@ 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: + CHECK_NUM_NONULL( (void*)Regs->Arg2, sizeof(tVFS_ACL) ); + ret = VFS_GetACL( Regs->Arg1, (void*)Regs->Arg2 ); + break; + + // Read Directory + case SYS_READDIR: + // 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: + 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; + } + // 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, + LogF("Log: [%i] ", Threads_GetTID()); + LogF((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; @@ -156,8 +345,39 @@ 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(Regs->Num != SYS_EXECVE) + LEAVE('x', ret); + else + LOG("Actual %i", ret); + # if DEBUG < 2 + } + # endif #endif } +/** + * \fn int Syscall_ValidString(const char *Addr) + * \brief Checks if a memory address contains a valid string + */ +int Syscall_ValidString(const char *Addr) +{ + // Check if the memory is user memory + if(!MM_IsUser( (tVAddr) Addr)) return 0; + + return CheckString( Addr ); +} + +/** + * \fn int Syscall_Valid(int Size, const void *Addr) + * \brief Checks if a memory address is valid + */ +int Syscall_Valid(int Size, const void *Addr) +{ + if(!MM_IsUser( (tVAddr)Addr )) return 0; + + return CheckMem( Addr, Size ); +}