diff options
Diffstat (limited to 'usr.bin/truss/i386-fbsd.c')
| -rw-r--r-- | usr.bin/truss/i386-fbsd.c | 323 |
1 files changed, 323 insertions, 0 deletions
diff --git a/usr.bin/truss/i386-fbsd.c b/usr.bin/truss/i386-fbsd.c new file mode 100644 index 0000000..82f1db0 --- /dev/null +++ b/usr.bin/truss/i386-fbsd.c @@ -0,0 +1,323 @@ +/* + * Copyright 1997 Sean Eric Fagan + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by Sean Eric Fagan + * 4. Neither the name of the author may be used to endorse or promote + * products derived from this software without specific prior written + * permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * 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 + * SUCH DAMAGE. + */ + +#ifndef lint +static const char rcsid[] = + "$FreeBSD$"; +#endif /* not lint */ + +/* + * 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/syscall.h> +#include <sys/ptrace.h> + +#include <machine/reg.h> +#include <machine/psl.h> + +#include <errno.h> +#include <fcntl.h> +#include <signal.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <time.h> +#include <unistd.h> + +#include "truss.h" +#include "syscall.h" +#include "extern.h" + +static int cpid = -1; + +#include "syscalls.h" + +static int nsyscalls = sizeof(syscallnames) / sizeof(syscallnames[0]); + +/* + * 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. + */ +static 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 */ +} fsc; + +/* Clear up and free parts of the fsc structure. */ +static __inline void +clear_fsc(void) { + if (fsc.args) { + free(fsc.args); + } + if (fsc.s_args) { + int i; + for (i = 0; i < fsc.nargs; i++) + if (fsc.s_args[i]) + free(fsc.s_args[i]); + free(fsc.s_args); + } + memset(&fsc, 0, sizeof(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 reg regs; + int syscall_num; + int i; + unsigned int parm_offset; + struct syscall *sc = NULL; + struct ptrace_io_desc iorequest; + cpid = trussinfo->curthread->tid; + + clear_fsc(); + + if (ptrace(PT_GETREGS, cpid, (caddr_t)®s, 0) < 0) + { + fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n"); + return; + } + parm_offset = regs.r_esp + sizeof(int); + + /* + * FreeBSD has two special kinds of system call redirctions -- + * SYS_syscall, and SYS___syscall. The former is the old syscall() + * routine, basically; the latter is for quad-aligned arguments. + */ + syscall_num = regs.r_eax; + switch (syscall_num) { + case SYS_syscall: + syscall_num = ptrace(PT_READ_D, cpid, (caddr_t)parm_offset, 0); + parm_offset += sizeof(int); + break; + case SYS___syscall: + syscall_num = ptrace(PT_READ_D, cpid, (caddr_t)parm_offset, 0); + parm_offset += sizeof(quad_t); + break; + } + + 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") + || !strcmp(fsc.name, "rfork") + || !strcmp(fsc.name, "vfork")))) + { + 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_offs = (void *)parm_offset; + iorequest.piod_addr = fsc.args; + iorequest.piod_len = (1+nargs) * sizeof(unsigned long); + ptrace(PT_IO, cpid, (caddr_t)&iorequest, 0); + if (iorequest.piod_len == 0) + return; + + 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*)); + 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 + + if (fsc.name != NULL && + (!strcmp(fsc.name, "execve") || !strcmp(fsc.name, "exit"))) { + + /* XXX + * This could be done in a more general + * manner but it still wouldn't be very pretty. + */ + if (!strcmp(fsc.name, "execve")) { + if ((trussinfo->flags & EXECVEARGS) == 0) + if (fsc.s_args[1]) { + free(fsc.s_args[1]); + fsc.s_args[1] = NULL; + } + if ((trussinfo->flags & EXECVEENVS) == 0) + if (fsc.s_args[2]) { + free(fsc.s_args[2]); + fsc.s_args[2] = NULL; + } + } + + } + + return; +} + +/* + * 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; + long retval; + int i; + int errorp; + struct syscall *sc; + + if (fsc.name == NULL) + return (-1); + cpid = trussinfo->curthread->tid; + + if (ptrace(PT_GETREGS, cpid, (caddr_t)®s, 0) < 0) + { + fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n"); + return (-1); + } + + retval = regs.r_eax; + errorp = !!(regs.r_eflags & PSL_C); + + /* + * This code, while simpler than the initial versions I used, could + * stand some significant cleaning. + */ + + 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") || !strcmp(fsc.name, "exit"))) { + trussinfo->curthread->in_syscall = 1; + } + + /* + * 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, + retval, fsc.sc); + clear_fsc(); + + return (retval); +} |
