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Cleaned up table. Moved policies to table.

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Small fixes to do_copy, do_privctl and do_fork.
This commit is contained in:
Jorrit Herder 2005-08-02 15:28:09 +00:00
parent 619a202720
commit ab7c0a9926
7 changed files with 95 additions and 84 deletions
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22
kernel/ipc.h
View file

@ -7,8 +7,6 @@
#define SYSCALL_FUNC 0x0F /* mask for system call function */
#define SYSCALL_FLAGS 0xF0 /* mask for system call flags */
#define NON_BLOCKING 0x10 /* prevent blocking, return error */
#define FRESH_ANSWER 0x20 /* ignore pending notifications as answer */
/* (default behaviour for SENDREC calls) */
/* System call numbers that are passed when trapping to the kernel. The
* numbers are carefully defined so that it can easily be seen (based on
@ -25,13 +23,6 @@
#define CHECK_DST 0x05 /* 0 1 0 1 : validate message destination */
#define CHECK_SRC 0x02 /* 0 0 1 0 : validate message source */
/* Call masks indicating which system calls (traps) a process can make.
* System processes can do anything; user processes are highly restricted.
*/
#define EMPTY_MASK (0)
#define FILLED_MASK (~0)
#define TASK_CALL_MASK (1 << RECEIVE)
#define USER_CALL_MASK ((1 << SENDREC) | (1 << ECHO))
/* Send masks determine to whom processes can send messages or notifications.
* The values here are used for the processes in the boot image. We rely on
@ -44,13 +35,12 @@
* "BITCHUNK_BITS - NR_TASKS", because a bitchunk_t field is used to store
* the send masks in the table that describes that processes in the image.
*/
#define s_nr_to_id(n) (NR_TASKS + (n) + 1)
#define s(n) (1 << s_nr_to_id(n))
#define USER_SEND_MASK (s(PM_PROC_NR) | s(FS_PROC_NR))
#define DRIVER_SEND_MASK (s(PM_PROC_NR) | s(FS_PROC_NR) | s(SYSTEM) | \
s(CLOCK) | s(PRINTF_PROC) | s(TTY))
#define SERVER_SEND_MASK (~0)
#define SYSTEM_SEND_MASK (~1)
#define s_nr_to_id(n) (NR_TASKS + (n) + 1)
#define s(n) (1 << s_nr_to_id(n))
#define SERV_M (~0)
#define SYST_M (~0)
#define USER_M (s(PM_PROC_NR)|s(FS_PROC_NR)|s(SM_PROC_NR))
#define DRIV_M (USER_M | s(SYSTEM)|s(CLOCK)|s(LOG_PROC_NR)|s(TTY))
/* Sanity check to make sure the send masks can be set. */
extern int dummy[(BITCHUNK_BITS-NR_TASKS > INIT_PROC_NR) ? 1 : -1];

4
kernel/proc.c
View file

@ -117,8 +117,10 @@ message *m_ptr; /* pointer to message in the caller's space */
return(ECALLDENIED);
/* Require a valid source and/ or destination process, unless echoing. */
if (! (isokprocn(src_dst) || src_dst == ANY || function == ECHO))
if (! (isokprocn(src_dst) || src_dst == ANY || function == ECHO)) {
kprintf("sys_call: function %d, src_dst %d\n", function, src_dst);
return(EBADSRCDST);
}
/* If the call involves a message buffer, i.e., for SEND, RECEIVE, SENDREC,
* or ECHO, check the message pointer. This check allows a message to be

1
kernel/proc.h
View file

@ -66,6 +66,7 @@ struct proc {
#define SIGNALED 0x10 /* set when new kernel signal arrives */
#define SIG_PENDING 0x20 /* unready while signal being processed */
#define P_STOP 0x40 /* set when process is being traced */
#define NO_PRIV 0x80 /* keep forked system process from running */
/* Scheduling priorities for p_priority. Values must start at zero (highest
* priority) and increment. Priorities of the processes in the boot image can

2
kernel/system/do_copy.c
View file

@ -27,7 +27,7 @@ register message *m_ptr; /* pointer to request message */
* are two different system calls so that permissions can be checked.
*/
struct vir_addr vir_addr[2]; /* virtual source and destination address */
vir_bytes bytes; /* number of bytes to copy */
phys_bytes bytes; /* number of bytes to copy */
int i;
/* Dismember the command message. */

18
kernel/system/do_fork.c
View file

@ -32,17 +32,19 @@ register message *m_ptr; /* pointer to request message */
rpc = proc_addr(m_ptr->PR_PROC_NR);
if (isemptyp(rpp) || ! isemptyp(rpc)) return(EINVAL);
/* If this is a system process, make sure the child process gets its own
* privilege structure for accounting. This is the only part that can fail,
* so do this before allocating the process table slot.
#if DEAD_CODE
/* If the parent is a privileged process, ensure the child process also gets
* its own privilege structure for accounting. This is the only part that can
* fail, so do this before allocating the process table slot.
*/
if (priv(rpc)->s_flags & SYS_PROC) {
if (priv(rpp)->s_flags & SYS_PROC) {
if (OK != (i=get_priv(rpc, SYS_PROC))) return(i); /* get structure */
for (i=0; i< BITMAP_CHUNKS(NR_SYS_PROCS); i++) /* remove pending: */
priv(rpc)->s_notify_pending.chunk[i] = 0; /* - notifications */
priv(rpc)->s_int_pending = 0; /* - interrupts */
sigemptyset(&priv(rpc)->s_sig_pending); /* - signals */
}
#endif
/* Copy parent 'proc' struct to child. And reinitialize some fields. */
#if (CHIP == INTEL)
@ -63,6 +65,14 @@ register message *m_ptr; /* pointer to request message */
rpc->p_user_time = 0; /* set all the accounting times to 0 */
rpc->p_sys_time = 0;
/* If the parent is a privileged process, take away the privileges from the
* child process and inhibit it from running by setting the NO_PRIV flag.
* The caller should explicitely set the new privileges before executing.
*/
if (priv(rpp)->s_flags & SYS_PROC) {
rpc->p_priv = priv_addr(USER_PRIV_ID);
rpc->p_rts_flags |= NO_PRIV;
}
return(OK);
}

43
kernel/system/do_privctl.c
View file

@ -2,14 +2,17 @@
* m_type: SYS_PRIVCTL
*
* The parameters for this system call are:
* m2_i1: CTL_PROC_NR (process number of caller)
* m1_i1: PR_PROC_NR (process number of caller)
*/
#include "../system.h"
#include "../ipc.h"
#include <signal.h>
#if USE_PRIVCTL
#define FILLED_MASK (~0)
/*===========================================================================*
* do_privctl *
*===========================================================================*/
@ -19,21 +22,40 @@ message *m_ptr; /* pointer to request message */
/* Handle sys_privctl(). Update a process' privileges. If the process is not
* yet a system process, make sure it gets its own privilege structure.
*/
register struct proc *caller_ptr;
register struct proc *rp;
register struct priv *sp;
int proc_nr;
int priv_id;
int old_flags;
int i;
/* Extract message parameters. */
proc_nr = m_ptr->CTL_PROC_NR;
if (proc_nr == SELF) proc_nr = m_ptr->m_source;
/* Check whether caller is allowed to make this call. Privileged proceses
* can only update the privileges of processes that are inhibited from
* running by the NO_PRIV flag. This flag is set when a privileged process
* forks.
*/
caller_ptr = proc_addr(m_ptr->m_source);
if (! (priv(caller_ptr)->s_flags & SYS_PROC)) return(EPERM);
proc_nr = m_ptr->PR_PROC_NR;
if (! isokprocn(proc_nr)) return(EINVAL);
rp = proc_addr(proc_nr);
if (! (rp->p_rts_flags & NO_PRIV)) return(EPERM);
/* Make sure this process has its own privileges structure. */
if (! (priv(rp)->s_flags & SYS_PROC))
if ((i=get_priv(rp, SYS_PROC)) != OK) return(i);
/* Make sure this process has its own privileges structure. This may fail,
* since there are only a limited number of system processes. Then copy the
* privileges from the caller and restore some defaults.
*/
if ((i=get_priv(rp, SYS_PROC)) != OK) return(i);
priv_id = priv(rp)->s_id; /* backup privilege id */
*priv(rp) = *priv(caller_ptr); /* copy privileges */
priv(rp)->s_id = priv_id; /* restore privilege id */
priv(rp)->s_proc_nr = proc_nr; /* reassociate process nr */
for (i=0; i< BITMAP_CHUNKS(NR_SYS_PROCS); i++) /* remove pending: */
priv(rp)->s_notify_pending.chunk[i] = 0; /* - notifications */
priv(rp)->s_int_pending = 0; /* - interrupts */
sigemptyset(&priv(rp)->s_sig_pending); /* - signals */
/* Now update the process' privileges as requested. */
rp->p_priv->s_call_mask = FILLED_MASK;
@ -50,6 +72,11 @@ message *m_ptr; /* pointer to request message */
set_sys_bit(priv_addr(i)->s_send_mask, priv_id(rp));
}
}
/* Done. Privileges have been set. Allow process to run again. */
old_flags = rp->p_rts_flags; /* save value of the flags */
rp->p_rts_flags &= ~NO_PRIV;
if (old_flags != 0 && rp->p_rts_flags == 0) lock_ready(rp);
return(OK);
}

89
kernel/table.c
View file

@ -26,7 +26,6 @@
* Oct 17, 2004 updated above and tasktab comments (Jorrit N. Herder)
* May 01, 2004 changed struct for system image (Jorrit N. Herder)
*/
#define _TABLE
#include "kernel.h"
@ -35,75 +34,57 @@
#include <minix/com.h>
#include <ibm/int86.h>
/* Define stack sizes for all tasks included in the system image. */
/* Define stack sizes for the kernel tasks included in the system image. */
#define NO_STACK 0
#define SMALL_STACK (128 * sizeof(char *))
#if (CHIP == INTEL) /* 3 intr, 3 temps, 4 db */
#define IDLE_S ((3+3+4) * sizeof(char *))
#else
#define IDLE_S SMALL_STACK
#endif
#define HARDWARE_S NO_STACK /* dummy task, uses kernel stack */
#define SYSTEM_S SMALL_STACK
#define CLOCK_S SMALL_STACK
#define IDLE_S SMALL_STACK /* 3 intr, 3 temps, 4 db for Intel */
#define HRDW_S NO_STACK /* dummy task, uses kernel stack */
#define TASK_S SMALL_STACK /* system and clock task */
/* Stack space for all the task stacks. Declared as (char *) to align it. */
#define TOT_STACK_SPACE (IDLE_S + HARDWARE_S + CLOCK_S + SYSTEM_S)
#define TOT_STACK_SPACE (IDLE_S + HRDW_S + (2 * TASK_S))
PUBLIC char *t_stack[TOT_STACK_SPACE / sizeof(char *)];
/* Define flags for the various process types. */
#define IDLE_F (BILLABLE | SYS_PROC) /* idle task */
#define TASK_F (SYS_PROC) /* kernel tasks */
#define SERV_F (PREEMPTIBLE | SYS_PROC) /* system services */
#define USER_F (PREEMPTIBLE | BILLABLE) /* user processes */
/* Define system call traps for the various process types. These call masks
* determine what system call traps a process is allowed to make.
*/
#define TASK_T (1 << RECEIVE) /* clock and system */
#define SERV_T (~0) /* system services */
#define USER_T ((1 << SENDREC) | (1 << ECHO)) /* user processes */
/* The system image table lists all programs that are part of the boot image.
* The order of the entries here MUST agree with the order of the programs
* in the boot image and all kernel tasks must come first.
* Each entry provides the process number, type, scheduling priority, send
* mask, and a name for the process table. For kernel processes, the startup
* routine and stack size is also provided.
* Each entry provides the process number, flags, quantum size (qs), scheduling
* queue, allowed traps, ipc mask, and a name for the process table. The
* initial program counter and stack size is also provided for kernel tasks.
*/
#define USER_F (PREEMPTIBLE | BILLABLE)
#define IDLE_F (BILLABLE | SYS_PROC)
#define SYS_F (PREEMPTIBLE | SYS_PROC)
#define TASK_F (SYS_PROC)
#define IDLE_T 32 /* ticks */
#define USER_T 8 /* ticks */
#define SYS_T 16 /* ticks */
PUBLIC struct boot_image image[] = {
{ IDLE, idle_task, IDLE_F, IDLE_T, IDLE_Q, IDLE_S, EMPTY_MASK, EMPTY_MASK, "IDLE" },
{ CLOCK, clock_task, TASK_F, SYS_T, TASK_Q, CLOCK_S, TASK_CALL_MASK, SYSTEM_SEND_MASK, "CLOCK" },
{ SYSTEM, sys_task, TASK_F, SYS_T, TASK_Q, SYSTEM_S, TASK_CALL_MASK, SYSTEM_SEND_MASK, "SYSTEM" },
{ HARDWARE, 0, TASK_F, SYS_T, TASK_Q, HARDWARE_S, EMPTY_MASK, SYSTEM_SEND_MASK, "KERNEL" },
{ PM_PROC_NR, 0, SYS_F, SYS_T, 3, 0, FILLED_MASK, SERVER_SEND_MASK, "PM" },
{ FS_PROC_NR, 0, SYS_F, SYS_T, 4, 0, FILLED_MASK, SERVER_SEND_MASK, "FS" },
{ SM_PROC_NR, 0, SYS_F, SYS_T, 3, 0, FILLED_MASK, SYSTEM_SEND_MASK, "SM" },
{ IS_PROC_NR, 0, SYS_F, SYS_T, 2, 0, FILLED_MASK, DRIVER_SEND_MASK, "IS" },
{ TTY, 0, SYS_F, SYS_T, 1, 0, FILLED_MASK, SYSTEM_SEND_MASK, "TTY" },
{ MEMORY, 0, SYS_F, SYS_T, 2, 0, FILLED_MASK, DRIVER_SEND_MASK, "MEMORY" },
/* process nr, pc, flags, qs, queue, stack, traps, ipc mask, name */
{ IDLE, idle_task, IDLE_F, 32, IDLE_Q, IDLE_S, 0, 0, "IDLE" },
{ CLOCK, clock_task, TASK_F, 0, TASK_Q, TASK_S, TASK_T, 0, "CLOCK" },
{ SYSTEM, sys_task, TASK_F, 0, TASK_Q, TASK_S, TASK_T, 0, "SYSTEM" },
{ HARDWARE, 0, TASK_F, 0, TASK_Q, HRDW_S, 0, 0, "KERNEL" },
{ PM_PROC_NR, 0, SERV_F, 16, 3, 0, SERV_T, SERV_M, "PM" },
{ FS_PROC_NR, 0, SERV_F, 16, 4, 0, SERV_T, SERV_M, "FS" },
{ SM_PROC_NR, 0, SERV_F, 16, 3, 0, SERV_T, SYST_M, "SM" },
{ TTY, 0, SERV_F, 16, 1, 0, SERV_T, SYST_M, "TTY" },
{ MEMORY, 0, SERV_F, 16, 2, 0, SERV_T, DRIV_M, "MEMORY" },
{ LOG_PROC_NR, 0, SERV_F, 16, 2, 0, SERV_T, SYST_M, "LOG" },
#if ENABLE_AT_WINI
{ AT_WINI, 0, SYS_F, SYS_T, 2, 0, FILLED_MASK, DRIVER_SEND_MASK, "AT_WINI" },
#endif
#if ENABLE_FLOPPY
{ FLOPPY, 0, SYS_F, SYS_T, 2, 0, FILLED_MASK, DRIVER_SEND_MASK, "FLOPPY" },
#endif
#if ENABLE_PRINTER
{ PRINTER, 0, SYS_F, SYS_T, 3, 0, FILLED_MASK, DRIVER_SEND_MASK, "PRINTER" },
#endif
#if ENABLE_RTL8139
{ RTL8139, 0, SYS_F, SYS_T, 2, 0, FILLED_MASK, DRIVER_SEND_MASK, "RTL8139" },
#endif
#if ENABLE_FXP
{ FXP, 0, SYS_F, SYS_T, 2, 0, FILLED_MASK, DRIVER_SEND_MASK, "FXP" },
#endif
#if ENABLE_DPETH
{ DPETH, 0, SYS_F, SYS_T, 2, 0, FILLED_MASK, DRIVER_SEND_MASK, "DPETH" },
#endif
#if ENABLE_LOG
{ LOG_PROC_NR, 0, SYS_F, SYS_T, 2, 0, FILLED_MASK, SYSTEM_SEND_MASK, "LOG" },
{ AT_WINI, 0, SERV_F, 16, 2, 0, SERV_T, DRIV_M, "AT_WINI" },
#endif
#if ENABLE_BIOS_WINI
{ BIOS_WINI, 0, SYS_F, SYS_T, 2, 0, FILLED_MASK, SYSTEM_SEND_MASK, "BIOS" },
{ BIOS_WINI, 0, SERV_F, 16, 2, 0, SERV_T, SYST_M, "BIOS" },
#endif
{ INIT_PROC_NR, 0, USER_F, USER_T, USER_Q, 0, USER_CALL_MASK, USER_SEND_MASK, "INIT" },
{ INIT_PROC_NR, 0, USER_F, 8, USER_Q, 0, USER_T, USER_M, "INIT" },
};
/* Verify the size of the system image table at compile time. If the number