/* set the thread x86 registers */
void set_thread_context( struct thread *thread, const context_t *context, unsigned int flags )
{
int pid = get_ptrace_tid(thread);
struct dbreg dbregs;
/* all other regs are handled on the client side */
assert( flags == SERVER_CTX_DEBUG_REGISTERS );
if (!suspend_for_ptrace( thread )) return;
#ifdef DBREG_DRX
/* needed for FreeBSD, the structure fields have changed under 5.x */
DBREG_DRX((&dbregs), 0) = context->debug.i386_regs.dr0;
DBREG_DRX((&dbregs), 1) = context->debug.i386_regs.dr1;
DBREG_DRX((&dbregs), 2) = context->debug.i386_regs.dr2;
DBREG_DRX((&dbregs), 3) = context->debug.i386_regs.dr3;
DBREG_DRX((&dbregs), 4) = 0;
DBREG_DRX((&dbregs), 5) = 0;
DBREG_DRX((&dbregs), 6) = context->debug.i386_regs.dr6;
DBREG_DRX((&dbregs), 7) = context->debug.i386_regs.dr7;
#else
dbregs.dr0 = context->debug.i386_regs.dr0;
dbregs.dr1 = context->debug.i386_regs.dr1;
dbregs.dr2 = context->debug.i386_regs.dr2;
dbregs.dr3 = context->debug.i386_regs.dr3;
dbregs.dr4 = 0;
dbregs.dr5 = 0;
dbregs.dr6 = context->debug.i386_regs.dr6;
dbregs.dr7 = context->debug.i386_regs.dr7;
#endif
if (ptrace( PTRACE_SETDBREGS, pid, (caddr_t) &dbregs, 0 ) == -1) file_set_error();
else if (thread->context)
thread->context->debug.i386_regs = context->debug.i386_regs; /* update the cached values */
resume_after_ptrace( thread );
}
/* retrieve an LDT selector entry */
void get_selector_entry( struct thread *thread, int entry, unsigned int *base,
unsigned int *limit, unsigned char *flags )
{
if (!thread->process->ldt_copy)
{
set_error( STATUS_ACCESS_DENIED );
return;
}
if (entry >= 8192)
{
set_error( STATUS_ACCESS_VIOLATION );
return;
}
if (suspend_for_ptrace( thread ))
{
unsigned char flags_buf[sizeof(long)];
long *addr = (long *)(unsigned long)thread->process->ldt_copy + entry;
if (read_thread_long( thread, addr, (long *)base ) == -1) goto done;
if (read_thread_long( thread, addr + 8192, (long *)limit ) == -1) goto done;
addr = (long *)(unsigned long)thread->process->ldt_copy + 2*8192 + (entry / sizeof(long));
if (read_thread_long( thread, addr, (long *)flags_buf ) == -1) goto done;
*flags = flags_buf[entry % sizeof(long)];
done:
resume_after_ptrace( thread );
}
}
/* retrieve the thread x86 registers */
void get_thread_context( struct thread *thread, context_t *context, unsigned int flags )
{
int pid = get_ptrace_tid(thread);
struct dbreg dbregs;
/* all other regs are handled on the client side */
assert( flags == SERVER_CTX_DEBUG_REGISTERS );
if (!suspend_for_ptrace( thread )) return;
if (ptrace( PTRACE_GETDBREGS, pid, (caddr_t) &dbregs, 0 ) == -1) file_set_error();
else
{
#ifdef DBREG_DRX
/* needed for FreeBSD, the structure fields have changed under 5.x */
context->debug.i386_regs.dr0 = DBREG_DRX((&dbregs), 0);
context->debug.i386_regs.dr1 = DBREG_DRX((&dbregs), 1);
context->debug.i386_regs.dr2 = DBREG_DRX((&dbregs), 2);
context->debug.i386_regs.dr3 = DBREG_DRX((&dbregs), 3);
context->debug.i386_regs.dr6 = DBREG_DRX((&dbregs), 6);
context->debug.i386_regs.dr7 = DBREG_DRX((&dbregs), 7);
#else
context->debug.i386_regs.dr0 = dbregs.dr0;
context->debug.i386_regs.dr1 = dbregs.dr1;
context->debug.i386_regs.dr2 = dbregs.dr2;
context->debug.i386_regs.dr3 = dbregs.dr3;
context->debug.i386_regs.dr6 = dbregs.dr6;
context->debug.i386_regs.dr7 = dbregs.dr7;
#endif
context->flags |= SERVER_CTX_DEBUG_REGISTERS;
}
resume_after_ptrace( thread );
}
/* set the thread x86 registers */
void set_thread_context( struct thread *thread, const context_t *context, unsigned int flags )
{
int pid = get_ptrace_tid( thread );
/* all other regs are handled on the client side */
assert( flags == SERVER_CTX_DEBUG_REGISTERS );
if (!suspend_for_ptrace( thread )) return;
switch (context->cpu)
{
case CPU_x86:
/* Linux 2.6.33+ does DR0-DR3 alignment validation, so it has to know LEN bits first */
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(7), context->debug.i386_regs.dr7 & 0xffff0000 ) == -1) goto error;
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(0), context->debug.i386_regs.dr0 ) == -1) goto error;
if (thread->context) thread->context->debug.i386_regs.dr0 = context->debug.i386_regs.dr0;
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(1), context->debug.i386_regs.dr1 ) == -1) goto error;
if (thread->context) thread->context->debug.i386_regs.dr1 = context->debug.i386_regs.dr1;
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(2), context->debug.i386_regs.dr2 ) == -1) goto error;
if (thread->context) thread->context->debug.i386_regs.dr2 = context->debug.i386_regs.dr2;
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(3), context->debug.i386_regs.dr3 ) == -1) goto error;
if (thread->context) thread->context->debug.i386_regs.dr3 = context->debug.i386_regs.dr3;
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(6), context->debug.i386_regs.dr6 ) == -1) goto error;
if (thread->context) thread->context->debug.i386_regs.dr6 = context->debug.i386_regs.dr6;
/* Linux 2.6.33+ needs enable bits set briefly to update value returned by PEEKUSER later */
ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(7), context->debug.i386_regs.dr7 | 0x55 );
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(7), context->debug.i386_regs.dr7 ) == -1) goto error;
if (thread->context) thread->context->debug.i386_regs.dr7 = context->debug.i386_regs.dr7;
break;
case CPU_x86_64:
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(7), context->debug.x86_64_regs.dr7 & 0xffff0000 ) == -1) goto error;
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(0), context->debug.x86_64_regs.dr0 ) == -1) goto error;
if (thread->context) thread->context->debug.x86_64_regs.dr0 = context->debug.x86_64_regs.dr0;
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(1), context->debug.x86_64_regs.dr1 ) == -1) goto error;
if (thread->context) thread->context->debug.x86_64_regs.dr1 = context->debug.x86_64_regs.dr1;
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(2), context->debug.x86_64_regs.dr2 ) == -1) goto error;
if (thread->context) thread->context->debug.x86_64_regs.dr2 = context->debug.x86_64_regs.dr2;
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(3), context->debug.x86_64_regs.dr3 ) == -1) goto error;
if (thread->context) thread->context->debug.x86_64_regs.dr3 = context->debug.x86_64_regs.dr3;
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(6), context->debug.x86_64_regs.dr6 ) == -1) goto error;
if (thread->context) thread->context->debug.x86_64_regs.dr6 = context->debug.x86_64_regs.dr6;
ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(7), context->debug.x86_64_regs.dr7 | 0x55 );
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(7), context->debug.x86_64_regs.dr7 ) == -1) goto error;
if (thread->context) thread->context->debug.x86_64_regs.dr7 = context->debug.x86_64_regs.dr7;
break;
default:
set_error( STATUS_INVALID_PARAMETER );
}
resume_after_ptrace( thread );
return;
error:
file_set_error();
resume_after_ptrace( thread );
}
/* set the thread x86 registers */
void set_thread_context( struct thread *thread, const context_t *context, unsigned int flags )
{
int pid = get_ptrace_tid( thread );
/* all other regs are handled on the client side */
assert( flags == SERVER_CTX_DEBUG_REGISTERS );
if (!suspend_for_ptrace( thread )) return;
switch (context->cpu)
{
case CPU_x86:
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(0), context->debug.i386_regs.dr0 ) == -1) goto error;
if (thread->context) thread->context->debug.i386_regs.dr0 = context->debug.i386_regs.dr0;
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(1), context->debug.i386_regs.dr1 ) == -1) goto error;
if (thread->context) thread->context->debug.i386_regs.dr1 = context->debug.i386_regs.dr1;
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(2), context->debug.i386_regs.dr2 ) == -1) goto error;
if (thread->context) thread->context->debug.i386_regs.dr2 = context->debug.i386_regs.dr2;
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(3), context->debug.i386_regs.dr3 ) == -1) goto error;
if (thread->context) thread->context->debug.i386_regs.dr3 = context->debug.i386_regs.dr3;
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(6), context->debug.i386_regs.dr6 ) == -1) goto error;
if (thread->context) thread->context->debug.i386_regs.dr6 = context->debug.i386_regs.dr6;
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(7), context->debug.i386_regs.dr7 ) == -1) goto error;
if (thread->context) thread->context->debug.i386_regs.dr7 = context->debug.i386_regs.dr7;
break;
case CPU_x86_64:
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(0), context->debug.x86_64_regs.dr0 ) == -1) goto error;
if (thread->context) thread->context->debug.x86_64_regs.dr0 = context->debug.x86_64_regs.dr0;
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(1), context->debug.x86_64_regs.dr1 ) == -1) goto error;
if (thread->context) thread->context->debug.x86_64_regs.dr1 = context->debug.x86_64_regs.dr1;
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(2), context->debug.x86_64_regs.dr2 ) == -1) goto error;
if (thread->context) thread->context->debug.x86_64_regs.dr2 = context->debug.x86_64_regs.dr2;
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(3), context->debug.x86_64_regs.dr3 ) == -1) goto error;
if (thread->context) thread->context->debug.x86_64_regs.dr3 = context->debug.x86_64_regs.dr3;
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(6), context->debug.x86_64_regs.dr6 ) == -1) goto error;
if (thread->context) thread->context->debug.x86_64_regs.dr6 = context->debug.x86_64_regs.dr6;
if (ptrace( PTRACE_POKEUSER, pid, DR_OFFSET(7), context->debug.x86_64_regs.dr7 ) == -1) goto error;
if (thread->context) thread->context->debug.x86_64_regs.dr7 = context->debug.x86_64_regs.dr7;
break;
default:
set_error( STATUS_INVALID_PARAMETER );
}
resume_after_ptrace( thread );
return;
error:
file_set_error();
resume_after_ptrace( thread );
}
/* retrieve the thread x86 registers */
void get_thread_context( struct thread *thread, context_t *context, unsigned int flags )
{
int i, pid = get_ptrace_tid(thread);
long data[8];
/* all other regs are handled on the client side */
assert( flags == SERVER_CTX_DEBUG_REGISTERS );
if (!suspend_for_ptrace( thread )) return;
for (i = 0; i < 8; i++)
{
if (i == 4 || i == 5) continue;
errno = 0;
data[i] = ptrace( PTRACE_PEEKUSER, pid, DR_OFFSET(i), 0 );
if ((data[i] == -1) && errno)
{
file_set_error();
goto done;
}
}
switch (context->cpu)
{
case CPU_x86:
context->debug.i386_regs.dr0 = data[0];
context->debug.i386_regs.dr1 = data[1];
context->debug.i386_regs.dr2 = data[2];
context->debug.i386_regs.dr3 = data[3];
context->debug.i386_regs.dr6 = data[6];
context->debug.i386_regs.dr7 = data[7];
break;
case CPU_x86_64:
context->debug.x86_64_regs.dr0 = data[0];
context->debug.x86_64_regs.dr1 = data[1];
context->debug.x86_64_regs.dr2 = data[2];
context->debug.x86_64_regs.dr3 = data[3];
context->debug.x86_64_regs.dr6 = data[6];
context->debug.x86_64_regs.dr7 = data[7];
break;
default:
set_error( STATUS_INVALID_PARAMETER );
goto done;
}
context->flags |= SERVER_CTX_DEBUG_REGISTERS;
done:
resume_after_ptrace( thread );
}
/* write data to a process memory space */
int write_process_memory( struct process *process, client_ptr_t ptr, data_size_t size, const char *src )
{
struct thread *thread = get_ptrace_thread( process );
int ret = 0;
long data = 0;
data_size_t len;
long *addr;
unsigned long first_mask, first_offset, last_mask, last_offset;
if (!thread) return 0;
if ((unsigned long)ptr != ptr)
{
set_error( STATUS_ACCESS_DENIED );
return 0;
}
/* compute the mask for the first long */
first_mask = ~0;
first_offset = ptr % sizeof(long);
memset( &first_mask, 0, first_offset );
/* compute the mask for the last long */
last_offset = (size + first_offset) % sizeof(long);
if (!last_offset) last_offset = sizeof(long);
last_mask = 0;
memset( &last_mask, 0xff, last_offset );
addr = (long *)(unsigned long)(ptr - first_offset);
len = (size + first_offset + sizeof(long) - 1) / sizeof(long);
if (suspend_for_ptrace( thread ))
{
if (!check_process_write_access( thread, addr, len ))
{
set_error( STATUS_ACCESS_DENIED );
goto done;
}
if (len > 3)
{
char procmem[24];
int fd;
sprintf( procmem, "/proc/%u/mem", process->unix_pid );
if ((fd = open( procmem, O_WRONLY )) != -1)
{
ssize_t r = pwrite( fd, src, size, ptr );
close( fd );
if (r == size)
{
ret = 1;
goto done;
}
}
}
/* first word is special */
if (len > 1)
{
memcpy( (char *)&data + first_offset, src, sizeof(long) - first_offset );
src += sizeof(long) - first_offset;
if (write_thread_long( thread, addr++, data, first_mask ) == -1) goto done;
first_offset = 0;
len--;
}
else last_mask &= first_mask;
while (len > 1)
{
memcpy( &data, src, sizeof(long) );
src += sizeof(long);
if (write_thread_long( thread, addr++, data, ~0ul ) == -1) goto done;
len--;
}
/* last word is special too */
memcpy( (char *)&data + first_offset, src, last_offset - first_offset );
if (write_thread_long( thread, addr, data, last_mask ) == -1) goto done;
ret = 1;
done:
resume_after_ptrace( thread );
}
return ret;
}
/* read data from a process memory space */
int read_process_memory( struct process *process, client_ptr_t ptr, data_size_t size, char *dest )
{
struct thread *thread = get_ptrace_thread( process );
unsigned int first_offset, last_offset, len;
long data, *addr;
if (!thread) return 0;
if ((unsigned long)ptr != ptr)
{
set_error( STATUS_ACCESS_DENIED );
return 0;
}
first_offset = ptr % sizeof(long);
last_offset = (size + first_offset) % sizeof(long);
if (!last_offset) last_offset = sizeof(long);
addr = (long *)(unsigned long)(ptr - first_offset);
len = (size + first_offset + sizeof(long) - 1) / sizeof(long);
if (suspend_for_ptrace( thread ))
{
if (len > 3) /* /proc/pid/mem should be faster for large sizes */
{
char procmem[24];
int fd;
sprintf( procmem, "/proc/%u/mem", process->unix_pid );
if ((fd = open( procmem, O_RDONLY )) != -1)
{
ssize_t ret = pread( fd, dest, size, ptr );
close( fd );
if (ret == size)
{
len = 0;
goto done;
}
}
}
if (len > 1)
{
if (read_thread_long( thread, addr++, &data ) == -1) goto done;
memcpy( dest, (char *)&data + first_offset, sizeof(long) - first_offset );
dest += sizeof(long) - first_offset;
first_offset = 0;
len--;
}
while (len > 1)
{
if (read_thread_long( thread, addr++, &data ) == -1) goto done;
memcpy( dest, &data, sizeof(long) );
dest += sizeof(long);
len--;
}
if (read_thread_long( thread, addr++, &data ) == -1) goto done;
memcpy( dest, (char *)&data + first_offset, last_offset - first_offset );
len--;
done:
resume_after_ptrace( thread );
}
return !len;
}
