/*===========================================================================*
* do_trace *
*===========================================================================*/
PUBLIC int do_trace()
{
register struct mproc *child;
/* the T_OK call is made by the child fork of the debugger before it execs
* the process to be traced
*/
if (m_in.request == T_OK) { /* enable tracing by parent for this proc */
mp->mp_flags |= TRACED;
mp->mp_reply.reply_trace = 0;
return(OK);
}
if ((child=find_proc(m_in.pid))==NIL_MPROC || !(child->mp_flags & STOPPED)) {
return(ESRCH);
}
/* all the other calls are made by the parent fork of the debugger to
* control execution of the child
*/
switch (m_in.request) {
case T_EXIT: /* exit */
pm_exit(child, (int) m_in.data);
mp->mp_reply.reply_trace = 0;
return(OK);
case T_RESUME:
case T_STEP: /* resume execution */
if (m_in.data < 0 || m_in.data > _NSIG) return(EIO);
if (m_in.data > 0) { /* issue signal */
child->mp_flags &= ~TRACED; /* so signal is not diverted */
sig_proc(child, (int) m_in.data);
child->mp_flags |= TRACED;
}
child->mp_flags &= ~STOPPED;
break;
}
if (sys_trace(m_in.request,(int)(child-mproc),m_in.taddr,&m_in.data) != OK)
return(-errno);
mp->mp_reply.reply_trace = m_in.data;
return(OK);
}
/*===========================================================================*
* do_trace *
*===========================================================================*/
PUBLIC int do_trace()
{
register struct mproc *child;
struct ptrace_range pr;
int i, r, seg, req;
req = m_in.request;
/* The T_OK call is made by the child fork of the debugger before it execs
* the process to be traced. The T_ATTACH call is made by the debugger itself
* to attach to an existing process.
*/
switch (req) {
case T_OK: /* enable tracing by parent for this proc */
if (mp->mp_tracer != NO_TRACER) return(EBUSY);
mp->mp_tracer = mp->mp_parent;
mp->mp_reply.reply_trace = 0;
return(OK);
case T_ATTACH: /* attach to an existing process */
if ((child = find_proc(m_in.pid)) == NULL) return(ESRCH);
if (child->mp_flags & EXITING) return(ESRCH);
/* For non-root processes, user and group ID must match. */
if (mp->mp_effuid != SUPER_USER &&
(mp->mp_effuid != child->mp_effuid ||
mp->mp_effgid != child->mp_effgid ||
child->mp_effuid != child->mp_realuid ||
child->mp_effgid != child->mp_realgid)) return(EPERM);
/* Only root may trace system servers. */
if (mp->mp_effuid != SUPER_USER && (child->mp_flags & PRIV_PROC))
return(EPERM);
/* System servers may not trace anyone. They can use sys_trace(). */
if (mp->mp_flags & PRIV_PROC) return(EPERM);
/* Can't trace self, PM or VM. */
if (child == mp || child->mp_endpoint == PM_PROC_NR ||
child->mp_endpoint == VM_PROC_NR) return(EPERM);
/* Can't trace a process that is already being traced. */
if (child->mp_tracer != NO_TRACER) return(EBUSY);
child->mp_tracer = who_p;
child->mp_trace_flags = TO_NOEXEC;
sig_proc(child, SIGSTOP, TRUE /*trace*/, FALSE /* ksig */);
mp->mp_reply.reply_trace = 0;
return(OK);
case T_STOP: /* stop the process */
/* This call is not exposed to user programs, because its effect can be
* achieved better by sending the traced process a signal with kill(2).
*/
return(EINVAL);
case T_READB_INS: /* special hack for reading text segments */
if (mp->mp_effuid != SUPER_USER) return(EPERM);
if ((child = find_proc(m_in.pid)) == NULL) return(ESRCH);
if (child->mp_flags & EXITING) return(ESRCH);
r = sys_trace(req, child->mp_endpoint, m_in.PMTRACE_ADDR, &m_in.data);
if (r != OK) return(r);
mp->mp_reply.reply_trace = m_in.data;
return(OK);
case T_WRITEB_INS: /* special hack for patching text segments */
if (mp->mp_effuid != SUPER_USER) return(EPERM);
if ((child = find_proc(m_in.pid)) == NULL) return(ESRCH);
if (child->mp_flags & EXITING) return(ESRCH);
#if 0
/* Should check for shared text */
/* Make sure the text segment is not used as a source for shared
* text.
*/
child->mp_ino = 0;
child->mp_dev = 0;
child->mp_ctime = 0;
#endif
r = sys_trace(req, child->mp_endpoint, m_in.PMTRACE_ADDR, &m_in.data);
if (r != OK) return(r);
mp->mp_reply.reply_trace = m_in.data;
return(OK);
}
/* All the other calls are made by the tracing process to control execution
* of the child. For all these calls, the child must be stopped.
*/
if ((child = find_proc(m_in.pid)) == NULL) return(ESRCH);
if (child->mp_flags & EXITING) return(ESRCH);
if (child->mp_tracer != who_p) return(ESRCH);
if (!(child->mp_flags & STOPPED)) return(EBUSY);
switch (req) {
case T_EXIT: /* exit */
child->mp_flags |= TRACE_EXIT;
/* Defer the exit if the traced process has an VFS call pending. */
if (child->mp_flags & VFS_CALL)
child->mp_exitstatus = (int) m_in.data; /* save for later */
else
exit_proc(child, (int) m_in.data, FALSE /*dump_core*/);
/* Do not reply to the caller until VFS has processed the exit
* request.
*/
return(SUSPEND);
case T_SETOPT: /* set trace options */
child->mp_trace_flags = m_in.data;
mp->mp_reply.reply_trace = 0;
return(OK);
case T_GETRANGE:
case T_SETRANGE: /* get/set range of values */
r = sys_datacopy(who_e, (vir_bytes) m_in.PMTRACE_ADDR,
SELF, (vir_bytes) &pr, (phys_bytes) sizeof(pr));
if (r != OK) return(r);
if (pr.pr_space != TS_INS && pr.pr_space != TS_DATA) return(EINVAL);
if (pr.pr_size == 0 || pr.pr_size > LONG_MAX) return(EINVAL);
seg = (pr.pr_space == TS_INS) ? T : D;
if (req == T_GETRANGE)
r = sys_vircopy(child->mp_endpoint, seg, (vir_bytes) pr.pr_addr,
who_e, D, (vir_bytes) pr.pr_ptr,
(phys_bytes) pr.pr_size);
else
r = sys_vircopy(who_e, D, (vir_bytes) pr.pr_ptr,
child->mp_endpoint, seg, (vir_bytes) pr.pr_addr,
(phys_bytes) pr.pr_size);
if (r != OK) return(r);
mp->mp_reply.reply_trace = 0;
return(OK);
case T_DETACH: /* detach from traced process */
if (m_in.data < 0 || m_in.data >= _NSIG) return(EINVAL);
child->mp_tracer = NO_TRACER;
/* Let all tracer-pending signals through the filter. */
for (i = 1; i < _NSIG; i++) {
if (sigismember(&child->mp_sigtrace, i)) {
(void) sigdelset(&child->mp_sigtrace, i);
check_sig(child->mp_pid, i, FALSE /* ksig */);
}
}
if (m_in.data > 0) { /* issue signal */
sig_proc(child, (int) m_in.data, TRUE /*trace*/,
FALSE /* ksig */);
}
/* Resume the child as if nothing ever happened. */
child->mp_flags &= ~STOPPED;
child->mp_trace_flags = 0;
check_pending(child);
break;
case T_RESUME:
case T_STEP:
case T_SYSCALL: /* resume execution */
if (m_in.data < 0 || m_in.data >= _NSIG) return(EINVAL);
if (m_in.data > 0) { /* issue signal */
sig_proc(child, (int) m_in.data, FALSE /*trace*/,
FALSE /* ksig */);
}
/* If there are any other signals waiting to be delivered,
* feign a successful resumption.
*/
for (i = 1; i < _NSIG; i++) {
if (sigismember(&child->mp_sigtrace, i)) {
mp->mp_reply.reply_trace = 0;
return(OK);
}
}
child->mp_flags &= ~STOPPED;
check_pending(child);
break;
}
r = sys_trace(req, child->mp_endpoint, m_in.PMTRACE_ADDR, &m_in.data);
if (r != OK) return(r);
mp->mp_reply.reply_trace = m_in.data;
return(OK);
}
