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Diffstat (limited to 'sysdeps/mach/hurd/ptrace.c')
| -rw-r--r-- | sysdeps/mach/hurd/ptrace.c | 392 |
1 files changed, 392 insertions, 0 deletions
diff --git a/sysdeps/mach/hurd/ptrace.c b/sysdeps/mach/hurd/ptrace.c new file mode 100644 index 0000000000..3d8558734f --- /dev/null +++ b/sysdeps/mach/hurd/ptrace.c @@ -0,0 +1,392 @@ +/* Process tracing interface `ptrace' for GNU Hurd. +Copyright (C) 1991, 1992, 1993, 1995 Free Software Foundation, Inc. +This file is part of the GNU C Library. + +The GNU C Library is free software; you can redistribute it and/or +modify it under the terms of the GNU Library General Public License as +published by the Free Software Foundation; either version 2 of the +License, or (at your option) any later version. + +The GNU C Library is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +#include <errno.h> +#include <sys/ptrace.h> +#include <sys/types.h> +#include <stdarg.h> +#include <hurd.h> +#include <hurd/signal.h> +#include <hurd/msg.h> +#include <thread_state.h> + +/* Perform process tracing functions. REQUEST is one of the values + in <sys/ptrace.h>, and determines the action to be taken. + For all requests except PTRACE_TRACEME, PID specifies the process to be + traced. + + PID and the other arguments described above for the various requests should + appear (those that are used for the particular request) as: + pid_t PID, void *ADDR, int DATA, void *ADDR2 + after PID. */ +int +ptrace (enum __ptrace_request request, ... ) +{ + pid_t pid; + void *addr, *addr2; + natural_t data; + va_list ap; + + /* Read data from PID's address space, from ADDR for DATA bytes. */ + error_t read_data (task_t task, vm_address_t *ourpage, vm_size_t *size) + { + /* Read the pages containing the addressed range. */ + error_t err; + *size = round_page (addr + data) - trunc_page (addr); + err = __vm_read (task, trunc_page (addr), *size, ourpage, size); + return err; + } + + /* Fetch the thread port for PID's user thread. */ + error_t fetch_user_thread (task_t task, thread_t *thread) + { + thread_t threadbuf[3], *threads = threadbuf; + mach_msg_type_number_t nthreads = 3, i; + error_t err = __task_threads (task, &threads, &nthreads); + if (err) + return err; + if (nthreads == 0) + return EINVAL; + *thread = threads[0]; /* Assume user thread is first. */ + for (i = 1; i < nthreads; ++i) + __mach_port_deallocate (__mach_task_self (), threads[i]); + if (threads != threadbuf) + __vm_deallocate (__mach_task_self (), + (vm_address_t) threads, nthreads * sizeof threads[0]); + return 0; + } + + /* Fetch a thread state structure from PID and store it at ADDR. */ + int get_regs (int flavor, mach_msg_type_number_t count) + { + error_t err; + task_t task = __pid2task (pid); + thread_t thread; + if (task == MACH_PORT_NULL) + return -1; + err = fetch_user_thread (task, &thread); + __mach_port_deallocate (__mach_task_self (), task); + if (!err) + err = __thread_get_state (thread, flavor, addr, &count); + __mach_port_deallocate (__mach_task_self (), thread); + return err ? __hurd_fail (err) : 0; + } + + + switch (request) + { + case PTRACE_TRACEME: + /* Make this process be traced. */ + _hurd_exec_flags |= EXEC_TRACED; + break; + + case PTRACE_CONT: + va_start (ap, request); + pid = va_arg (ap, pid_t); + addr = va_arg (ap, void *); + data = va_arg (ap, int); + va_end (ap); + { + /* Send a DATA signal to PID, telling it to take the signal + normally even if it's traced. */ + error_t err; task_t task = __pid2task (pid); + if (task == MACH_PORT_NULL) + return -1; + if (data == SIGKILL) + err = __task_terminate (task); + else + { + mach_port_t msgport; + err = __USEPORT (PROC, __proc_getmsgport (port, pid, &msgport)); + + if (!err && addr != (void *) 1) + { + /* Move the user thread's PC to ADDR. */ + thread_t thread; + err = fetch_user_thread (task, &thread); + if (!err) + { + struct machine_thread_state state; + mach_msg_type_number_t count = MACHINE_THREAD_STATE_COUNT; + err = __thread_get_state (thread, + MACHINE_THREAD_STATE_FLAVOR, + (natural_t *) &state, &count); + if (!err) + { + MACHINE_THREAD_STATE_SET_PC (&state, addr); + err = __thread_set_state (thread, + MACHINE_THREAD_STATE_FLAVOR, + (natural_t *) &state, count); + } + + } + __mach_port_deallocate (__mach_task_self (), thread); + } + + if (! err) + /* Tell the process to take the signal (or just resume if 0). */ + err = __msg_sig_post_untraced (msgport, data, task); + __mach_port_deallocate (__mach_task_self (), msgport); + } + __mach_port_deallocate (__mach_task_self (), task); + return err ? __hurd_fail (err) : 0; + } + + case PTRACE_KILL: + va_start (ap, request); + pid = va_arg (ap, pid_t); + va_end (ap); + /* SIGKILL always just terminates the task, + so normal kill is just the same when traced. */ + return kill (pid, SIGKILL); + + case PTRACE_SINGLESTEP: + /* This is a machine-dependent kernel RPC on + machines that support it. Punt. */ + return EOPNOTSUPP; + + case PTRACE_ATTACH: + case PTRACE_DETACH: + va_start (ap, request); + pid = va_arg (ap, pid_t); + va_end (ap); + { + /* Tell PID to set or clear its trace bit. */ + error_t err; + mach_port_t msgport; + task_t task = __pid2task (pid); + if (task == MACH_PORT_NULL) + return -1; + err = __USEPORT (PROC, __proc_getmsgport (port, pid, &msgport)); + if (! err) + { + err = (request == PTRACE_ATTACH ? + __msg_set_some_exec_flags : + __msg_clear_some_exec_flags) (msgport, task, EXEC_TRACED); +#ifdef notyet /* XXX */ + if (! err) + /* Request (or request an end to) SIGCHLD notification + when PID stops or dies, and proc_wait working on PID. */ + err = __USEPORT (PROC, + __proc_trace_pid (port, pid, + request == PTRACE_ATTACH)); +#endif + if (! err) + { + if (request == PTRACE_ATTACH) + /* Now stop the process. */ + err = __msg_sig_post (msgport, SIGSTOP, task); + else + /* Resume the process from tracing stop. */ + err = __msg_sig_post_untraced (msgport, 0, task); + } + __mach_port_deallocate (__mach_task_self (), msgport); + } + __mach_port_deallocate (__mach_task_self (), task); + return err ? __hurd_fail (err) : 0; + } + + case PTRACE_PEEKTEXT: + case PTRACE_PEEKDATA: + va_start (ap, request); + pid = va_arg (ap, pid_t); + addr = va_arg (ap, void *); + va_end (ap); + { + /* Read the page (or two pages, if the word lies on a boundary) + containing the addressed word. */ + error_t err; + vm_address_t ourpage; + vm_size_t size; + natural_t word; + task_t task = __pid2task (pid); + if (task == MACH_PORT_NULL) + return -1; + data = sizeof word; + ourpage = 0; + size = 0; + err = read_data (task, &ourpage, &size); + __mach_port_deallocate (__mach_task_self (), task); + if (err) + return __hurd_fail (err); + word = *(natural_t *) ((vm_address_t) addr - trunc_page (addr) + + ourpage); + __vm_deallocate (__mach_task_self (), ourpage, size); + return word; + } + + case PTRACE_PEEKUSER: + case PTRACE_POKEUSER: + /* U area, what's that? */ + return EOPNOTSUPP; + + case PTRACE_GETREGS: + case PTRACE_SETREGS: + va_start (ap, request); + pid = va_arg (ap, pid_t); + addr = va_arg (ap, void *); + va_end (ap); + return get_regs (MACHINE_THREAD_STATE_FLAVOR, + MACHINE_THREAD_STATE_COUNT); + + case PTRACE_GETFPREGS: + case PTRACE_SETFPREGS: + va_start (ap, request); + pid = va_arg (ap, pid_t); + addr = va_arg (ap, void *); + va_end (ap); +#ifdef MACHINE_THREAD_FLOAT_STATE_FLAVOR + return get_regs (MACHINE_THREAD_FLOAT_STATE_FLAVOR, + MACHINE_THREAD_FLOAT_STATE_COUNT); +#else + return EOPNOTSUPP; +#endif + + case PTRACE_GETFPAREGS: + case PTRACE_SETFPAREGS: + va_start (ap, request); + pid = va_arg (ap, pid_t); + addr = va_arg (ap, void *); + va_end (ap); +#ifdef MACHINE_THREAD_FPA_STATE_FLAVOR + return get_regs (MACHINE_THREAD_FPA_STATE_FLAVOR, + MACHINE_THREAD_FPA_STATE_COUNT); +#else + return EOPNOTSUPP; +#endif + + case PTRACE_POKETEXT: + case PTRACE_POKEDATA: + va_start (ap, request); + pid = va_arg (ap, pid_t); + addr = va_arg (ap, void *); + data = va_arg (ap, int); + va_end (ap); + { + /* Read the page (or two pages, if the word lies on a boundary) + containing the addressed word. */ + error_t err; + vm_address_t ourpage; + vm_size_t size; + task_t task = __pid2task (pid); + if (task == MACH_PORT_NULL) + return -1; + data = sizeof (natural_t); + ourpage = 0; + size = 0; + err = read_data (task, &ourpage, &size); + + if (!err) + { + /* Now modify the specified word and write the page back. */ + *(natural_t *) ((vm_address_t) addr - trunc_page (addr) + + ourpage) = data; + err = __vm_write (task, trunc_page (addr), ourpage, size); + __vm_deallocate (__mach_task_self (), ourpage, size); + } + + __mach_port_deallocate (__mach_task_self (), task); + return err ? __hurd_fail (err) : 0; + } + + case PTRACE_READDATA: + case PTRACE_READTEXT: + va_start (ap, request); + pid = va_arg (ap, pid_t); + addr = va_arg (ap, void *); + data = va_arg (ap, int); + addr2 = va_arg (ap, void *); + va_end (ap); + { + error_t err; + vm_address_t ourpage; + vm_size_t size; + task_t task = __pid2task (pid); + if (task == MACH_PORT_NULL) + return -1; + if (((vm_address_t) addr2 + data) % __vm_page_size == 0) + { + /* Perhaps we can write directly to the user's buffer. */ + ourpage = (vm_address_t) addr2; + size = data; + } + else + { + ourpage = 0; + size = 0; + } + err = read_data (task, &ourpage, &size); + __mach_port_deallocate (__mach_task_self (), task); + if (!err && ourpage != (vm_address_t) addr2) + { + memcpy (addr2, (void *) ourpage, data); + __vm_deallocate (__mach_task_self (), ourpage, size); + } + return err ? __hurd_fail (err) : 0; + } + + case PTRACE_WRITEDATA: + case PTRACE_WRITETEXT: + va_start (ap, request); + pid = va_arg (ap, pid_t); + addr = va_arg (ap, void *); + data = va_arg (ap, int); + addr2 = va_arg (ap, void *); + va_end (ap); + { + error_t err; + vm_address_t ourpage; + vm_size_t size; + task_t task = __pid2task (pid); + if (task == MACH_PORT_NULL) + return -1; + if ((vm_address_t) addr % __vm_page_size == 0 && + (vm_address_t) data % __vm_page_size == 0) + { + /* Writing whole pages; can go directly from the user's buffer. */ + ourpage = (vm_address_t) addr2; + size = data; + err = 0; + } + else + { + /* Read the task's pages and modify our own copy. */ + ourpage = 0; + size = 0; + err = read_data (task, &ourpage, &size); + if (!err) + memcpy ((void *) ((vm_address_t) addr - trunc_page (addr) + + ourpage), + addr2, + data); + } + if (!err) + /* Write back the modified pages. */ + err = __vm_write (task, trunc_page (addr), ourpage, size); + __mach_port_deallocate (__mach_task_self (), task); + return err ? __hurd_fail (err) : 0; + } + + default: + errno = EINVAL; + return -1; + } + + return 0; +} |