2 * Copyright 1997 Sean Eric Fagan
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 * 3. All advertising materials mentioning features or use of this software
13 * must display the following acknowledgement:
14 * This product includes software developed by Sean Eric Fagan
15 * 4. Neither the name of the author may be used to endorse or promote
16 * products derived from this software without specific prior written
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 static const char rcsid[] =
38 * FreeBSD/i386-specific system call handling. This is probably the most
39 * complex part of the entire truss program, although I've got lots of
40 * it handled relatively cleanly now. The system call names are generated
41 * automatically, thanks to /usr/src/sys/kern/syscalls.master. The
42 * names used for the various structures are confusing, I sadly admit.
45 #include <sys/types.h>
46 #include <sys/ptrace.h>
47 #include <sys/syscall.h>
49 #include <machine/reg.h>
50 #include <machine/psl.h>
65 #include "freebsd32_syscalls.h"
67 static int nsyscalls = sizeof(freebsd32_syscallnames) /
68 sizeof(freebsd32_syscallnames[0]);
71 * This is what this particular file uses to keep track of a system call.
72 * It is probably not quite sufficient -- I can probably use the same
73 * structure for the various syscall personalities, and I also probably
74 * need to nest system calls (for signal handlers).
76 * 'struct syscall' describes the system call; it may be NULL, however,
77 * if we don't know about this particular system call yet.
79 struct freebsd32_syscall {
85 int nargs; /* number of arguments -- *not* number of words! */
86 char **s_args; /* the printable arguments */
89 static struct freebsd32_syscall *
93 return (malloc(sizeof(struct freebsd32_syscall)));
96 /* Clear up and free parts of the fsc structure. */
98 free_fsc(struct freebsd32_syscall *fsc)
105 for (i = 0; i < fsc->nargs; i++)
106 free(fsc->s_args[i]);
113 * Called when a process has entered a system call. nargs is the
114 * number of words, not number of arguments (a necessary distinction
115 * in some cases). Note that if the STOPEVENT() code in i386/i386/trap.c
116 * is ever changed these functions need to keep up.
120 amd64_fbsd32_syscall_entry(struct trussinfo *trussinfo, int nargs)
122 struct ptrace_io_desc iorequest;
124 struct freebsd32_syscall *fsc;
127 unsigned long parm_offset;
130 tid = trussinfo->curthread->tid;
132 if (ptrace(PT_GETREGS, tid, (caddr_t)®s, 0) < 0) {
133 fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
136 parm_offset = regs.r_rsp + sizeof(int);
139 * FreeBSD has two special kinds of system call redirctions --
140 * SYS_syscall, and SYS___syscall. The former is the old syscall()
141 * routine, basically; the latter is for quad-aligned arguments.
143 syscall_num = regs.r_rax;
144 switch (syscall_num) {
146 syscall_num = ptrace(PT_READ_D, tid, (caddr_t)parm_offset, 0);
147 parm_offset += sizeof(int);
150 syscall_num = ptrace(PT_READ_D, tid, (caddr_t)parm_offset, 0);
151 parm_offset += sizeof(quad_t);
158 fsc->number = syscall_num;
159 fsc->name = (syscall_num < 0 || syscall_num >= nsyscalls) ?
160 NULL : freebsd32_syscallnames[syscall_num];
162 fprintf(trussinfo->outfile, "-- UNKNOWN SYSCALL %d --\n",
166 if (fsc->name && (trussinfo->flags & FOLLOWFORKS) &&
167 (strcmp(fsc->name, "fork") == 0 ||
168 strcmp(fsc->name, "rfork") == 0 ||
169 strcmp(fsc->name, "vfork") == 0))
170 trussinfo->curthread->in_fork = 1;
175 fsc->args32 = malloc((1 + nargs) * sizeof(unsigned int));
176 iorequest.piod_op = PIOD_READ_D;
177 iorequest.piod_offs = (void *)parm_offset;
178 iorequest.piod_addr = fsc->args32;
179 iorequest.piod_len = (1 + nargs) * sizeof(unsigned int);
180 ptrace(PT_IO, tid, (caddr_t)&iorequest, 0);
181 if (iorequest.piod_len == 0)
184 fsc->args = malloc((1 + nargs) * sizeof(unsigned long));
185 for (i = 0; i < nargs + 1; i++)
186 fsc->args[i] = fsc->args32[i];
190 sc = get_syscall(fsc->name);
192 fsc->nargs = sc->nargs;
195 fprintf(trussinfo->outfile, "unknown syscall %s -- setting "
196 "args to %d\n", fsc->name, nargs);
201 fsc->s_args = calloc(1, (1 + fsc->nargs) * sizeof(char *));
205 * At this point, we set up the system call arguments.
206 * We ignore any OUT ones, however -- those are arguments that
207 * are set by the system call, and so are probably meaningless
208 * now. This doesn't currently support arguments that are
209 * passed in *and* out, however.
214 fprintf(stderr, "syscall %s(", fsc->name);
216 for (i = 0; i < fsc->nargs; i++) {
218 fprintf(stderr, "0x%x%s", sc ?
219 fsc->args[sc->args[i].offset] : fsc->args[i],
220 i < (fsc->nargs - 1) ? "," : "");
222 if (sc && !(sc->args[i].type & OUT)) {
223 fsc->s_args[i] = print_arg(&sc->args[i],
224 fsc->args, 0, trussinfo);
228 fprintf(stderr, ")\n");
233 fprintf(trussinfo->outfile, "\n");
236 if (fsc->name != NULL && (strcmp(fsc->name, "freebsd32_execve") == 0 ||
237 strcmp(fsc->name, "exit") == 0)) {
240 * This could be done in a more general
241 * manner but it still wouldn't be very pretty.
243 if (strcmp(fsc->name, "freebsd32_execve") == 0) {
244 if ((trussinfo->flags & EXECVEARGS) == 0) {
245 if (fsc->s_args[1]) {
246 free(fsc->s_args[1]);
247 fsc->s_args[1] = NULL;
250 if ((trussinfo->flags & EXECVEENVS) == 0) {
251 if (fsc->s_args[2]) {
252 free(fsc->s_args[2]);
253 fsc->s_args[2] = NULL;
258 trussinfo->curthread->fsc = fsc;
262 * And when the system call is done, we handle it here.
263 * Currently, no attempt is made to ensure that the system calls
264 * match -- this needs to be fixed (and is, in fact, why S_SCX includes
265 * the system call number instead of, say, an error status).
269 amd64_fbsd32_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused)
272 struct freebsd32_syscall *fsc;
278 if (trussinfo->curthread->fsc == NULL)
281 tid = trussinfo->curthread->tid;
283 if (ptrace(PT_GETREGS, tid, (caddr_t)®s, 0) < 0) {
284 fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n");
289 errorp = !!(regs.r_rflags & PSL_C);
292 * This code, while simpler than the initial versions I used, could
293 * stand some significant cleaning.
296 fsc = trussinfo->curthread->fsc;
299 for (i = 0; i < fsc->nargs; i++)
300 asprintf(&fsc->s_args[i], "0x%lx", fsc->args[i]);
303 * Here, we only look for arguments that have OUT masked in --
304 * otherwise, they were handled in the syscall_entry function.
306 for (i = 0; i < sc->nargs; i++) {
308 if (sc->args[i].type & OUT) {
310 * If an error occurred, then don't bother
311 * getting the data; it may not be valid.
314 asprintf(&temp, "0x%lx",
315 fsc->args[sc->args[i].offset]);
317 temp = print_arg(&sc->args[i],
318 fsc->args, retval, trussinfo);
320 fsc->s_args[i] = temp;
325 if (fsc->name != NULL && (strcmp(fsc->name, "freebsd32_execve") == 0 ||
326 strcmp(fsc->name, "exit") == 0))
327 trussinfo->curthread->in_syscall = 1;
330 * It would probably be a good idea to merge the error handling,
331 * but that complicates things considerably.
334 print_syscall_ret(trussinfo, fsc->name, fsc->nargs, fsc->s_args, errorp,