Differential D3575 Diff 8935 usr.bin/truss/i386-linux.c

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usr.bin/truss/i386-linux.c

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	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS			* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)			* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT			* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY			* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF			* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	* SUCH DAMAGE.			* SUCH DAMAGE.
	*/			*/

	#ifndef lint			#include <sys/cdefs.h>
	static const char rcsid[] =			__FBSDID("$FreeBSD$");
	"$FreeBSD$";
	#endif /* not lint */

	/*			/* Linux/i386-specific system call handling. */
	* Linux/i386-specific system call handling. Given how much of this code
	* is taken from the freebsd equivalent, I can probably put even more of
	* it in support routines that can be used by any personality support.
	*/

	#include <sys/types.h>
	#include <sys/ptrace.h>			#include <sys/ptrace.h>

	#include <machine/reg.h>			#include <machine/reg.h>
	#include <machine/psl.h>			#include <machine/psl.h>

	#include <errno.h>
	#include <fcntl.h>
	#include <signal.h>
	#include <stdio.h>			#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>
	#include <time.h>
	#include <unistd.h>

	#include "truss.h"			#include "truss.h"
	#include "syscall.h"
	#include "extern.h"

	#include "linux_syscalls.h"			#include "linux_syscalls.h"

	static int nsyscalls = nitems(linux_syscallnames);			static int
				i386_linux_fetch_args(struct trussinfo *trussinfo, u_int narg)
	/*
	* This is what this particular file uses to keep track of a system call.
	* It is probably not quite sufficient -- I can probably use the same
	* structure for the various syscall personalities, and I also probably
	* need to nest system calls (for signal handlers).
	*
	* 'struct syscall' describes the system call; it may be NULL, however,
	* if we don't know about this particular system call yet.
	*/
	struct linux_syscall {
	struct syscall *sc;
	const char *name;
	int number;
	unsigned long args[5];
	int nargs; /* number of arguments -- not number of words! */
	char *s_args; / the printable arguments */
	};

	static struct linux_syscall *
	alloc_fsc(void)
	{			{

	return (malloc(sizeof(struct linux_syscall)));
	}

	/* Clear up and free parts of the fsc structure. */
	static void
	free_fsc(struct linux_syscall *fsc)
	{
	int i;

	if (fsc->s_args) {
	for (i = 0; i < fsc->nargs; i++)
	free(fsc->s_args[i]);
	free(fsc->s_args);
	}
	free(fsc);
	}

	/*
	* Called when a process has entered a system call. nargs is the
	* number of words, not number of arguments (a necessary distinction
	* in some cases). Note that if the STOPEVENT() code in i386/i386/trap.c
	* is ever changed these functions need to keep up.
	*/

	void
	i386_linux_syscall_entry(struct trussinfo *trussinfo, int nargs)
	{
	struct reg regs;			struct reg regs;
	struct linux_syscall *fsc;			struct current_syscall *cs;
	struct syscall *sc;
	lwpid_t tid;			lwpid_t tid;
	int i, syscall_num;

	tid = trussinfo->curthread->tid;			tid = trussinfo->curthread->tid;
				cs = &trussinfo->curthread->cs;
	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {			if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
	fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");			fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
	return;			return (-1);
	}			}

	syscall_num = regs.r_eax;

	fsc = alloc_fsc();
	if (fsc == NULL)
	return;
	fsc->number = syscall_num;
	fsc->name = (syscall_num < 0 \|\| syscall_num >= nsyscalls) ?
	NULL : linux_syscallnames[syscall_num];
	if (!fsc->name) {
	fprintf(trussinfo->outfile, "-- UNKNOWN SYSCALL %d --\n",
	syscall_num);
	}

	if (fsc->name && (trussinfo->flags & FOLLOWFORKS) &&
	(strcmp(fsc->name, "linux_fork") == 0 \|\|
	strcmp(fsc->name, "linux_vfork") == 0))
	trussinfo->curthread->in_fork = 1;

	if (nargs == 0)
	return;

	/*			/*
	* Linux passes syscall arguments in registers, not			* Linux passes syscall arguments in registers, not
	* on the stack. Fortunately, we've got access to the			* on the stack. Fortunately, we've got access to the
	* register set. Note that we don't bother checking the			* register set. Note that we don't bother checking the
	* number of arguments. And what does linux do for syscalls			* number of arguments. And what does linux do for syscalls
	* that have more than five arguments?			* that have more than five arguments?
	*/			*/
				switch (narg) {
	fsc->args[0] = regs.r_ebx;			default:
	fsc->args[1] = regs.r_ecx;			cs->args[5] = regs.r_ebp; /* Unconfirmed */
	fsc->args[2] = regs.r_edx;			case 5:
	fsc->args[3] = regs.r_esi;			cs->args[4] = regs.r_edi;
	fsc->args[4] = regs.r_edi;			case 4:
				cs->args[3] = regs.r_esi;
	sc = get_syscall(fsc->name);			case 3:
	if (sc)			cs->args[2] = regs.r_edx;
	fsc->nargs = sc->nargs;			case 2:
	else {			cs->args[1] = regs.r_ecx;
	#if DEBUG			case 1:
	fprintf(trussinfo->outfile, "unknown syscall %s -- setting "			cs->args[0] = regs.r_ebx;
	"args to %d\n", fsc->name, nargs);
	#endif
	fsc->nargs = nargs;
	}			}

	fsc->s_args = calloc(1, (1 + fsc->nargs) * sizeof(char *));			return (0);
	fsc->sc = sc;

	/*
	* At this point, we set up the system call arguments.
	* We ignore any OUT ones, however -- those are arguments that
	* are set by the system call, and so are probably meaningless
	* now. This doesn't currently support arguments that are
	* passed in and out, however.
	*/

	if (fsc->name) {
	#if DEBUG
	fprintf(stderr, "syscall %s(", fsc->name);
	#endif
	for (i = 0; i < fsc->nargs; i++) {
	#if DEBUG
	fprintf(stderr, "0x%x%s", sc ?
	fsc->args[sc->args[i].offset] : fsc->args[i],
	i < (fsc->nargs - 1) ? "," : "");
	#endif
	if (sc && !(sc->args[i].type & OUT)) {
	fsc->s_args[i] = print_arg(&sc->args[i],
	fsc->args, 0, trussinfo);
	}			}
	}
	#if DEBUG
	fprintf(stderr, ")\n");
	#endif
	}

	#if DEBUG
	fprintf(trussinfo->outfile, "\n");
	#endif

	trussinfo->curthread->fsc = fsc;
	}

	/*			/*
	* Linux syscalls return negative errno's, we do positive and map them			* Linux syscalls return negative errno's, we do positive and map them
	*/			*/
	static const int bsd_to_linux_errno[] = {			static const int bsd_to_linux_errno[] = {
	-0, -1, -2, -3, -4, -5, -6, -7, -8, -9,			-0, -1, -2, -3, -4, -5, -6, -7, -8, -9,
	-10, -35, -12, -13, -14, -15, -16, -17, -18, -19,			-10, -35, -12, -13, -14, -15, -16, -17, -18, -19,
	-20, -21, -22, -23, -24, -25, -26, -27, -28, -29,			-20, -21, -22, -23, -24, -25, -26, -27, -28, -29,
	-30, -31, -32, -33, -34, -11,-115,-114, -88, -89,			-30, -31, -32, -33, -34, -11,-115,-114, -88, -89,
	-90, -91, -92, -93, -94, -95, -96, -97, -98, -99,			-90, -91, -92, -93, -94, -95, -96, -97, -98, -99,
	-100,-101,-102,-103,-104,-105,-106,-107,-108,-109,			-100,-101,-102,-103,-104,-105,-106,-107,-108,-109,
	-110,-111, -40, -36,-112,-113, -39, -11, -87,-122,			-110,-111, -40, -36,-112,-113, -39, -11, -87,-122,
	-116, -66, -6, -6, -6, -6, -6, -37, -38, -9,			-116, -66, -6, -6, -6, -6, -6, -37, -38, -9,
	-6,			-6,
	};			};

	long			static int
	i386_linux_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)			i386_linux_fetch_retval(struct trussinfo trussinfo, long retval, int *errorp)
	{			{
	struct reg regs;			struct reg regs;
	struct linux_syscall *fsc;
	struct syscall *sc;
	lwpid_t tid;			lwpid_t tid;
	long retval;			size_t i;
	int errorp, i;

	if (trussinfo->curthread->fsc == NULL)
	return (-1);

	tid = trussinfo->curthread->tid;			tid = trussinfo->curthread->tid;

	if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {			if (ptrace(PT_GETREGS, tid, (caddr_t)&regs, 0) < 0) {
	fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");			fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
	return (-1);			return (-1);
	}			}

	retval = regs.r_eax;			retval[0] = regs.r_eax;
	errorp = !!(regs.r_eflags & PSL_C);			retval[1] = regs.r_edx;
				*errorp = !!(regs.r_eflags & PSL_C);

	/*			if (*errorp) {
	* This code, while simpler than the initial versions I used, could			for (i = 0; i < nitems(bsd_to_linux_errno); i++) {
	* stand some significant cleaning.			if (retval[0] == bsd_to_linux_errno[i]) {
	*/			retval[0] = i;
				return (0);
	fsc = trussinfo->curthread->fsc;
	sc = fsc->sc;
	if (!sc) {
	for (i = 0; i < fsc->nargs; i++)
	asprintf(&fsc->s_args[i], "0x%lx", fsc->args[i]);
	} else {
	/*
	* Here, we only look for arguments that have OUT masked in --
	* otherwise, they were handled in the syscall_entry function.
	*/
	for (i = 0; i < sc->nargs; i++) {
	char *temp;

	if (sc->args[i].type & OUT) {
	/*
	* If an error occurred, then don't bother
	* getting the data; it may not be valid.
	*/
	if (errorp) {
	asprintf(&temp, "0x%lx",
	fsc->args[sc->args[i].offset]);
	} else {
	temp = print_arg(&sc->args[i],
	fsc->args, retval, trussinfo);
	}			}
	fsc->s_args[i] = temp;
	}			}
	}
	}

	/*			/* XXX: How to handle unknown errors? */
	* It would probably be a good idea to merge the error handling,
	* but that complicates things considerably.
	*/
	if (errorp) {
	for (i = 0; (size_t)i < nitems(bsd_to_linux_errno); i++) {
	if (retval == bsd_to_linux_errno[i])
	break;
	}			}
				return (0);
	}			}

	if (fsc->name != NULL && (strcmp(fsc->name, "linux_execve") == 0 \|\|			static struct procabi i386_linux = {
	strcmp(fsc->name, "exit") == 0))			"Linux ELF32",
	trussinfo->curthread->in_syscall = 1;			linux_syscallnames,
				nitems(linux_syscallnames),
				i386_linux_fetch_args,
				i386_linux_fetch_retval
				};

	print_syscall_ret(trussinfo, fsc->name, fsc->nargs, fsc->s_args, errorp,			PROCABI(i386_linux);
	errorp ? i : retval, fsc->sc);
	free_fsc(fsc);

	return (retval);
	}