Differential D3575 Diff 8983 usr.bin/truss/i386-fbsd.c

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usr.bin/truss/i386-fbsd.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 */

	/*			/* FreeBSD/i386-specific system call handling. */
	* FreeBSD/i386-specific system call handling. This is probably the most
	* complex part of the entire truss program, although I've got lots of
	* it handled relatively cleanly now. The system call names are generated
	* automatically, thanks to /usr/src/sys/kern/syscalls.master. The
	* names used for the various structures are confusing, I sadly admit.
	*/

	#include <sys/types.h>
	#include <sys/ptrace.h>			#include <sys/ptrace.h>
	#include <sys/syscall.h>			#include <sys/syscall.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 "syscalls.h"			#include "syscalls.h"

	static int nsyscalls = nitems(syscallnames);			static int
				i386_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 freebsd_syscall {
	struct syscall *sc;
	const char *name;
	int number;
	unsigned long *args;
	int nargs; /* number of arguments -- not number of words! */
	char *s_args; / the printable arguments */
	};

	static struct freebsd_syscall *
	alloc_fsc(void)
	{			{

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

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

	free(fsc->args);
	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_syscall_entry(struct trussinfo *trussinfo, int nargs)
	{
	struct ptrace_io_desc iorequest;			struct ptrace_io_desc iorequest;
	struct reg regs;			struct reg regs;
	struct freebsd_syscall *fsc;			struct current_syscall *cs;
	struct syscall *sc;
	lwpid_t tid;			lwpid_t tid;
	unsigned int parm_offset;			unsigned int parm_offset;
	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);
	}			}
	parm_offset = regs.r_esp + sizeof(int);			parm_offset = regs.r_esp + sizeof(int);

	/*			/*
	* FreeBSD has two special kinds of system call redirctions --			* FreeBSD has two special kinds of system call redirections --
	* SYS_syscall, and SYS___syscall. The former is the old syscall()			* SYS_syscall, and SYS___syscall. The former is the old syscall()
	* routine, basically; the latter is for quad-aligned arguments.			* routine, basically; the latter is for quad-aligned arguments.
				*
				* The system call argument count and code from ptrace() already
				* account for these, but we need to skip over the first argument.
	*/			*/
	syscall_num = regs.r_eax;			switch (regs.r_eax) {
	switch (syscall_num) {
	case SYS_syscall:			case SYS_syscall:
	syscall_num = ptrace(PT_READ_D, tid, (caddr_t)parm_offset, 0);
	parm_offset += sizeof(int);			parm_offset += sizeof(int);
	break;			break;
	case SYS___syscall:			case SYS___syscall:
	syscall_num = ptrace(PT_READ_D, tid, (caddr_t)parm_offset, 0);
	parm_offset += sizeof(quad_t);			parm_offset += sizeof(quad_t);
	break;			break;
	}			}

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

	if (fsc->name && (trussinfo->flags & FOLLOWFORKS) &&
	(strcmp(fsc->name, "fork") == 0 \|\|
	strcmp(fsc->name, "pdfork") == 0 \|\|
	strcmp(fsc->name, "rfork") == 0 \|\|
	strcmp(fsc->name, "vfork") == 0))
	trussinfo->curthread->in_fork = 1;

	if (nargs == 0)
	return;

	fsc->args = malloc((1 + nargs) * sizeof(unsigned long));
	iorequest.piod_op = PIOD_READ_D;			iorequest.piod_op = PIOD_READ_D;
	iorequest.piod_offs = (void *)parm_offset;			iorequest.piod_offs = (void *)parm_offset;
	iorequest.piod_addr = fsc->args;			iorequest.piod_addr = cs->args;
	iorequest.piod_len = (1 + nargs) * sizeof(unsigned long);			iorequest.piod_len = narg * sizeof(unsigned long);
	ptrace(PT_IO, tid, (caddr_t)&iorequest, 0);			ptrace(PT_IO, tid, (caddr_t)&iorequest, 0);
	if (iorequest.piod_len == 0)			if (iorequest.piod_len == 0)
	return;			return (-1);

	sc = NULL;			return (0);
	if (fsc->name)
	sc = get_syscall(fsc->name);
	if (sc)
	fsc->nargs = sc->nargs;
	else {
	#if DEBUG
	fprintf(trussinfo->outfile, "unknown syscall %s -- setting "
	"args to %d\n", fsc->name, nargs);
	#endif
	fsc->nargs = nargs;
	}			}

	fsc->s_args = calloc(1, (1 + fsc->nargs) * sizeof(char *));			static int
	fsc->sc = sc;			i386_fetch_retval(struct trussinfo trussinfo, long retval, int *errorp)

	/*
	* 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;
	}

	/*
	* And when the system call is done, we handle it here.
	* Currently, no attempt is made to ensure that the system calls
	* match -- this needs to be fixed (and is, in fact, why S_SCX includes
	* the system call number instead of, say, an error status).
	*/

	long
	i386_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
	{			{
	struct reg regs;			struct reg regs;
	struct freebsd_syscall *fsc;
	struct syscall *sc;
	lwpid_t tid;			lwpid_t tid;
	long retval;
	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);
	/*			return (0);
	* This code, while simpler than the initial versions I used, could
	* stand some significant cleaning.
	*/

	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;
	}
	}
	}

	if (fsc->name != NULL && (strcmp(fsc->name, "execve") == 0 \|\|			static struct procabi i386_fbsd = {
	strcmp(fsc->name, "exit") == 0))			"FreeBSD ELF32",
	trussinfo->curthread->in_syscall = 1;			syscallnames,
				nitems(syscallnames),
				i386_fetch_args,
				i386_fetch_retval
				};

	/*			PROCABI(i386_fbsd);
	* It would probably be a good idea to merge the error handling,
	* but that complicates things considerably.
	*/

	print_syscall_ret(trussinfo, fsc->name, fsc->nargs, fsc->s_args, errorp,			static struct procabi i386_fbsd_aout = {
	retval, fsc->sc);			"FreeBSD a.out",
	free_fsc(fsc);			syscallnames,
				nitems(syscallnames),
				i386_fetch_args,
				i386_fetch_retval
				};

	return (retval);			PROCABI(i386_fbsd_aout);
	}