993 lines
22 KiB
C
993 lines
22 KiB
C
/* $NetBSD: intercept.c,v 1.25 2005/06/27 17:11:20 elad Exp $ */
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/* $OpenBSD: intercept.c,v 1.29 2002/08/28 03:30:27 itojun Exp $ */
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/*
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* Copyright 2002 Niels Provos <provos@citi.umich.edu>
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by Niels Provos.
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* 4. The name of the author may not be used to endorse or promote products
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* derived from this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#include <sys/cdefs.h>
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__RCSID("$NetBSD: intercept.c,v 1.25 2005/06/27 17:11:20 elad Exp $");
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#include <sys/types.h>
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#include <sys/param.h>
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#include <sys/tree.h>
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#include <sys/wait.h>
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#include <sys/stat.h>
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#include <limits.h>
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#include <signal.h>
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#include <stdlib.h>
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#include <string.h>
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#include <poll.h>
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#include <fcntl.h>
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#include <stdio.h>
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#include <unistd.h>
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#include <errno.h>
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#include <err.h>
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#include <libgen.h>
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#include <pwd.h>
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#include "intercept.h"
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void simplify_path(char *);
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struct intercept_syscall {
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SPLAY_ENTRY(intercept_syscall) node;
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char name[64];
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char emulation[16];
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short (*cb)(int, pid_t, int, const char *, int, const char *, void *,
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int, struct intercept_replace *, struct intercept_tlq *, void *);
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void *cb_arg;
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struct intercept_tlq tls;
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};
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static int sccompare(struct intercept_syscall *, struct intercept_syscall *);
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static int pidcompare(struct intercept_pid *, struct intercept_pid *);
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static struct intercept_syscall *intercept_sccb_find(const char *,
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const char *);
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static void sigusr1_handler(int);
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static SPLAY_HEAD(pidtree, intercept_pid) pids;
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static SPLAY_HEAD(sctree, intercept_syscall) scroot;
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static volatile int got_sigusr1 = 0;
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/* Generic callback functions */
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void (*intercept_newimagecb)(int, pid_t, int, const char *, const char *, void *) = NULL;
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void *intercept_newimagecbarg = NULL;
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short (*intercept_gencb)(int, pid_t, int, const char *, int, const char *, void *, int, void *) = NULL;
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void *intercept_gencbarg = NULL;
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void (*intercept_pfreecb)(int, void*);
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void *intercept_pfreearg = NULL;
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int
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sccompare(struct intercept_syscall *a, struct intercept_syscall *b)
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{
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int diff;
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diff = strcmp(a->emulation, b->emulation);
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if (diff)
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return (diff);
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return (strcmp(a->name, b->name));
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}
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int
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pidcompare(struct intercept_pid *a, struct intercept_pid *b)
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{
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int diff = a->pid - b->pid;
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if (diff == 0)
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return (0);
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if (diff > 0)
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return (1);
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return (-1);
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}
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SPLAY_PROTOTYPE(sctree, intercept_syscall, node, sccompare);
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SPLAY_GENERATE(sctree, intercept_syscall, node, sccompare);
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SPLAY_PROTOTYPE(pidtree, intercept_pid, next, pidcompare);
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SPLAY_GENERATE(pidtree, intercept_pid, next, pidcompare);
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extern struct intercept_system intercept;
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int ic_abort;
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int
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intercept_init(void)
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{
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SPLAY_INIT(&pids);
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SPLAY_INIT(&scroot);
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intercept_newimagecb = NULL;
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intercept_gencb = NULL;
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return (intercept.init());
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}
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struct intercept_syscall *
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intercept_sccb_find(const char *emulation, const char *name)
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{
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struct intercept_syscall tmp;
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strlcpy(tmp.name, name, sizeof(tmp.name));
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strlcpy(tmp.emulation, emulation, sizeof(tmp.emulation));
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return (SPLAY_FIND(sctree, &scroot, &tmp));
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}
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struct intercept_translate *
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intercept_register_translation(const char *emulation, const char *name,
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int offset, struct intercept_translate *tl)
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{
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struct intercept_syscall *tmp;
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struct intercept_translate *tlnew;
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if (offset >= INTERCEPT_MAXSYSCALLARGS)
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errx(1, "%s: %s-%s: offset too large",
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__func__, emulation, name);
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tmp = intercept_sccb_find(emulation, name);
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if (tmp == NULL)
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errx(1, "%s: %s-%s: can't find call back",
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__func__, emulation, name);
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tlnew = malloc(sizeof(struct intercept_translate));
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if (tlnew == NULL)
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err(1, "%s: %s-%s: malloc",
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__func__, emulation, name);
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memcpy(tlnew, tl, sizeof(struct intercept_translate));
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tlnew->off = offset;
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TAILQ_INSERT_TAIL(&tmp->tls, tlnew, next);
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return (tlnew);
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}
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void *
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intercept_sccb_cbarg(char *emulation, char *name)
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{
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struct intercept_syscall *tmp;
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if ((tmp = intercept_sccb_find(emulation, name)) == NULL)
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return (NULL);
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return (tmp->cb_arg);
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}
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int
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intercept_register_sccb(const char *emulation, const char *name,
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short (*cb)(int, pid_t, int, const char *, int, const char *, void *, int,
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struct intercept_replace *, struct intercept_tlq *, void *),
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void *cbarg)
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{
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struct intercept_syscall *tmp;
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if (intercept_sccb_find(emulation, name))
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return (-1);
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if (intercept.getsyscallnumber(emulation, name) == -1) {
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warnx("%s: %d: unknown syscall: %s-%s", __func__, __LINE__,
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emulation, name);
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return (-1);
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}
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if ((tmp = calloc(1, sizeof(struct intercept_syscall))) == NULL) {
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warn("%s:%d: malloc", __func__, __LINE__);
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return (-1);
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}
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TAILQ_INIT(&tmp->tls);
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strlcpy(tmp->name, name, sizeof(tmp->name));
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strlcpy(tmp->emulation, emulation, sizeof(tmp->emulation));
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tmp->cb = cb;
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tmp->cb_arg = cbarg;
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SPLAY_INSERT(sctree, &scroot, tmp);
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return (0);
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}
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int
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intercept_register_gencb(short (*cb)(int, pid_t, int, const char *, int, const char *, void *, int, void *), void *arg)
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{
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intercept_gencb = cb;
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intercept_gencbarg = arg;
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return (0);
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}
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int
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intercept_register_execcb(void (*cb)(int, pid_t, int, const char *, const char *, void *), void *arg)
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{
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intercept_newimagecb = cb;
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intercept_newimagecbarg = arg;
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return (0);
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}
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int
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intercept_register_pfreecb(void (*cb)(int, void *), void *arg)
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{
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intercept_pfreecb = cb;
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intercept_pfreearg = arg;
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return (0);
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}
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static void
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sigusr1_handler(int signum)
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{
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/* all we need to do is pretend to handle it */
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got_sigusr1 = 1;
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}
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void
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intercept_setpid(struct intercept_pid *icpid, uid_t uid, gid_t gid)
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{
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struct passwd *pw;
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icpid->uid = uid;
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icpid->gid = gid;
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if ((pw = getpwuid(icpid->uid)) == NULL) {
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snprintf(icpid->username, sizeof(icpid->username),
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"unknown(%d)", icpid->uid);
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strlcpy(icpid->home, "/var/empty", sizeof(icpid->home));
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} else {
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strlcpy(icpid->username, pw->pw_name, sizeof(icpid->username));
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strlcpy(icpid->home, pw->pw_dir, sizeof(icpid->home));
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}
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}
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pid_t
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intercept_run(int bg, int fd, uid_t uid, gid_t gid,
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char *path, char *const argv[])
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{
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struct intercept_pid *icpid;
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sigset_t none, set, oset;
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sig_t ohandler;
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pid_t pid, cpid;
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int status;
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/* Block signals so that timeing on signal delivery does not matter */
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sigemptyset(&none);
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sigemptyset(&set);
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sigaddset(&set, SIGUSR1);
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if (sigprocmask(SIG_BLOCK, &set, &oset) == -1)
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err(1, "sigprocmask");
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ohandler = signal(SIGUSR1, sigusr1_handler);
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if (ohandler == SIG_ERR)
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err(1, "signal");
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pid = getpid();
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cpid = fork();
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if (cpid == -1)
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return (-1);
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/*
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* If the systrace process should be in the background and we're
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* the parent, or vice versa.
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*/
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if ((!bg && cpid == 0) || (bg && cpid != 0)) {
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/* Needs to be closed */
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close(fd);
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if (bg) {
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/* Wait for child to "detach" */
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cpid = wait(&status);
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if (cpid == -1)
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err(1, "wait");
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if (status != 0)
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errx(1, "wait: child gave up");
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}
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/* Sleep */
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sigsuspend(&none);
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if (!got_sigusr1)
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errx(1, "wrong signal");
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/*
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* Woken up, restore signal handling state.
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*
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* Note that there is either no child or we have no idea
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* what pid it might have at this point. If we fail.
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*/
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if (signal(SIGUSR1, ohandler) == SIG_ERR)
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err(1, "signal");
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if (sigprocmask(SIG_SETMASK, &oset, NULL) == -1)
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err(1, "sigprocmask");
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/* Change to different user */
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if (uid || gid) {
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if (setgroups(1, &gid) == -1)
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err(1, "setgroups");
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if (setgid(gid) == -1)
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err(1, "setgid");
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if (setegid(gid) == -1)
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err(1, "setegid");
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if (setuid(uid) == -1)
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err(1, "setuid");
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if (seteuid(uid) == -1)
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err(1, "seteuid");
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}
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execvp(path, argv);
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/* Error */
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err(1, "execvp");
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}
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/* Choose the pid of the systraced process */
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pid = bg ? pid : cpid;
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icpid = intercept_getpid(pid);
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/* Set up user related information */
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if (!uid && !gid) {
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uid = getuid();
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gid = getgid();
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}
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intercept_setpid(icpid, uid, gid);
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/* Setup done, restore signal handling state */
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if (signal(SIGUSR1, ohandler) == SIG_ERR) {
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kill(pid, SIGKILL);
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err(1, "signal");
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}
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if (sigprocmask(SIG_SETMASK, &oset, NULL) == -1) {
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kill(pid, SIGKILL);
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err(1, "sigprocmask");
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}
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if (bg) {
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if (daemon(1, 1) == -1) {
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kill(pid, SIGKILL);
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err(1, "daemon");
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}
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}
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return (pid);
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}
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int
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intercept_existpids(void)
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{
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return (SPLAY_ROOT(&pids) != NULL);
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}
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void
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intercept_freepid(pid_t pidnr)
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{
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struct intercept_pid *pid, tmp2;
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tmp2.pid = pidnr;
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pid = SPLAY_FIND(pidtree, &pids, &tmp2);
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if (pid == NULL)
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return;
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intercept.freepid(pid);
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SPLAY_REMOVE(pidtree, &pids, pid);
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if (pid->name)
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free(pid->name);
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if (pid->newname)
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free(pid->newname);
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free(pid);
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}
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struct intercept_pid *
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intercept_findpid(pid_t pid)
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{
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struct intercept_pid *tmp, tmp2;
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tmp2.pid = pid;
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tmp = SPLAY_FIND(pidtree, &pids, &tmp2);
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return (tmp);
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}
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struct intercept_pid *
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intercept_getpid(pid_t pid)
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{
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struct intercept_pid *tmp, tmp2;
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tmp2.pid = pid;
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tmp = SPLAY_FIND(pidtree, &pids, &tmp2);
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if (tmp)
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return (tmp);
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if ((tmp = malloc(sizeof(struct intercept_pid))) == NULL)
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err(1, "%s: malloc", __func__);
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memset(tmp, 0, sizeof(struct intercept_pid));
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tmp->pid = pid;
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SPLAY_INSERT(pidtree, &pids, tmp);
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return (tmp);
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}
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int
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intercept_open(void)
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{
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int fd;
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if ((fd = intercept.open()) == -1)
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return (-1);
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if (fcntl(fd, F_SETFL, O_NONBLOCK) == -1)
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warn("fcntl(O_NONBLOCK)");
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return (fd);
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}
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int
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intercept_attach(int fd, pid_t pid)
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{
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return (intercept.attach(fd, pid));
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}
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int
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intercept_attachpid(int fd, pid_t pid, char *name)
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{
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struct intercept_pid *icpid;
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int res;
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res = intercept.attach(fd, pid);
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if (res == -1)
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return (-1);
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icpid = intercept_getpid(pid);
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if ((icpid->newname = strdup(name)) == NULL)
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err(1, "strdup");
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if (intercept.report(fd, pid) == -1)
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return (-1);
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/* Indicates a running attach */
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icpid->execve_code = -1;
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return (0);
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}
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int
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intercept_detach(int fd, pid_t pid)
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{
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int res;
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res = intercept.detach(fd, pid);
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if (res != -1)
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intercept_freepid(pid);
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return (res);
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}
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int
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intercept_read(int fd)
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{
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struct pollfd pollfd;
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int n;
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pollfd.fd = fd;
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pollfd.events = POLLIN;
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do {
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n = poll(&pollfd, 1, -1);
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if (n == -1) {
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if (errno != EINTR && errno != EAGAIN)
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return (-1);
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}
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} while (n <= 0);
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if (!(pollfd.revents & (POLLIN|POLLRDNORM)))
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return (-1);
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return (intercept.read(fd));
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}
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int
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intercept_replace_init(struct intercept_replace *repl)
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{
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memset(repl, 0, sizeof(struct intercept_replace));
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return (0);
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}
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int
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intercept_replace_add(struct intercept_replace *repl, int off,
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u_char *addr, size_t len, u_int flags)
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{
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int ind = repl->num;
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if (ind >= INTERCEPT_MAXSYSCALLARGS)
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return (-1);
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repl->ind[ind] = off;
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repl->address[ind] = addr;
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repl->len[ind] = len;
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repl->flags[ind] = flags;
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repl->num++;
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return (0);
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}
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int
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intercept_replace(int fd, pid_t pid, u_int16_t seqnr,
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struct intercept_replace *repl)
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{
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if (repl->num == 0)
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return (0);
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return (intercept.replace(fd, pid, seqnr, repl));
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}
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char *
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intercept_get_string(int fd, pid_t pid, void *addr)
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{
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static char name[8192];
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int off = 0, done = 0, stride;
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stride = 32;
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do {
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if (intercept.io(fd, pid, INTERCEPT_READ, (char *)addr + off,
|
|
&name[off], stride) == -1) {
|
|
/* Did the current system call get interrupted? */
|
|
if (errno == EBUSY)
|
|
return (NULL);
|
|
if (errno != EINVAL || stride == 4) {
|
|
warn("%s: ioctl", __func__);
|
|
return (NULL);
|
|
}
|
|
|
|
/* Try smaller stride */
|
|
stride /= 2;
|
|
continue;
|
|
}
|
|
|
|
off += stride;
|
|
name[off] = '\0';
|
|
if (strlen(name) < off)
|
|
done = 1;
|
|
|
|
} while (!done && off + stride + 1 < sizeof(name));
|
|
|
|
if (!done) {
|
|
warnx("%s: string too long", __func__);
|
|
return (NULL);
|
|
}
|
|
|
|
return (name);
|
|
}
|
|
|
|
char *
|
|
intercept_filename(int fd, pid_t pid, void *addr, int userp, char *before)
|
|
{
|
|
char *name;
|
|
|
|
if ((name = intercept_get_string(fd, pid, addr)) == NULL)
|
|
goto abort;
|
|
|
|
if (before != NULL)
|
|
strlcpy(before, name, MAXPATHLEN);
|
|
|
|
if ((name = normalize_filename(fd, pid, name, userp)) == NULL)
|
|
goto abort;
|
|
|
|
return (name);
|
|
|
|
abort:
|
|
ic_abort = 1;
|
|
return (NULL);
|
|
}
|
|
|
|
/*
|
|
* Normalizes a pathname so that Systrace policies entries are
|
|
* invariant to symlinks.
|
|
*/
|
|
|
|
char *
|
|
normalize_filename(int fd, pid_t pid, char *name, int userp)
|
|
{
|
|
static char cwd[2*MAXPATHLEN];
|
|
int havecwd = 0;
|
|
|
|
/*
|
|
* The empty filename does not receive normalization.
|
|
* System calls are supposed to fail on it.
|
|
*/
|
|
if (strcmp(name, "") == 0)
|
|
return (name);
|
|
|
|
if (fd != -1 && intercept.setcwd(fd, pid) == -1) {
|
|
if (errno == EBUSY)
|
|
return (NULL);
|
|
getcwderr:
|
|
if (strcmp(name, "/") == 0)
|
|
return (name);
|
|
|
|
err(1, "%s: getcwd", __func__);
|
|
}
|
|
|
|
if (userp == ICLINK_NONE) {
|
|
if (getcwd(cwd, sizeof(cwd)) == NULL)
|
|
goto getcwderr;
|
|
havecwd = 1;
|
|
}
|
|
|
|
/* Need concatenated path for simplifypath */
|
|
if (havecwd && name[0] != '/') {
|
|
if (strlcat(cwd, "/", sizeof(cwd)) >= sizeof(cwd))
|
|
return (NULL);
|
|
if (strlcat(cwd, name, sizeof(cwd)) >= sizeof(cwd))
|
|
return (NULL);
|
|
} else {
|
|
if (strlcpy(cwd, name, sizeof(cwd)) >= sizeof(cwd))
|
|
return (NULL);
|
|
}
|
|
|
|
if (userp != ICLINK_NONE) {
|
|
static char rcwd[2*MAXPATHLEN];
|
|
char *base = basename(cwd);
|
|
int failed = 0;
|
|
|
|
/* The dot may be used by rmdir("/tmp/something/.") */
|
|
if (strcmp(base, ".") == 0)
|
|
goto nolast;
|
|
|
|
if (userp == ICLINK_NOLAST) {
|
|
/* Check if the last component has special meaning */
|
|
if (strcmp(base, "..") == 0 || strcmp(base, "/") == 0)
|
|
userp = ICLINK_ALL;
|
|
else
|
|
goto nolast;
|
|
}
|
|
|
|
/* If realpath fails then the filename does not exist,
|
|
* or we are supposed to not resolve the last component */
|
|
if (realpath(cwd, rcwd) == NULL) {
|
|
char *dir, *file;
|
|
struct stat st;
|
|
|
|
if (errno != EACCES) {
|
|
failed = 1;
|
|
goto out;
|
|
}
|
|
|
|
nolast:
|
|
/* Component of path could not be entered */
|
|
if (strlcpy(rcwd, cwd, sizeof(rcwd)) >= sizeof(rcwd))
|
|
goto error;
|
|
if ((file = basename(rcwd)) == NULL)
|
|
goto error;
|
|
if ((dir = dirname(rcwd)) == NULL)
|
|
goto error;
|
|
|
|
/* So, try again */
|
|
if (realpath(dir, rcwd) == NULL) {
|
|
failed = 1;
|
|
goto out;
|
|
}
|
|
/* If path is not "/" append a "/" */
|
|
if (strlen(rcwd) > 1 &&
|
|
strlcat(rcwd, "/", sizeof(rcwd)) >= sizeof(rcwd))
|
|
goto error;
|
|
if (strlcat(rcwd, file, sizeof(rcwd)) >= sizeof(rcwd))
|
|
goto error;
|
|
/*
|
|
* At this point, filename has to exist and has to
|
|
* be a directory.
|
|
*/
|
|
if (userp != ICLINK_NOLAST) {
|
|
if (lstat(rcwd, &st) == -1 ||
|
|
!(st.st_mode & S_IFDIR))
|
|
failed = 1;
|
|
}
|
|
}
|
|
out:
|
|
if (failed)
|
|
snprintf(rcwd, sizeof(rcwd),
|
|
"/<non-existent filename>: %s", cwd);
|
|
name = rcwd;
|
|
} else {
|
|
simplify_path(cwd);
|
|
name = cwd;
|
|
}
|
|
|
|
|
|
/* Restore working directory and change root space after realpath */
|
|
if (fd != -1 && intercept.restcwd(fd) == -1)
|
|
err(1, "%s: restcwd", __func__);
|
|
|
|
return (name);
|
|
|
|
error:
|
|
errx(1, "%s: filename too long", __func__);
|
|
/* NOTREACHED */
|
|
}
|
|
|
|
void
|
|
intercept_syscall(int fd, pid_t pid, u_int16_t seqnr, int policynr,
|
|
const char *name, int code, const char *emulation, void *args, int argsize)
|
|
{
|
|
short action, flags = 0;
|
|
struct intercept_syscall *sc;
|
|
struct intercept_pid *icpid;
|
|
struct elevate *elevate = NULL;
|
|
int error = 0;
|
|
|
|
action = ICPOLICY_PERMIT;
|
|
flags = 0;
|
|
|
|
icpid = intercept_getpid(pid);
|
|
|
|
/* Special handling for the exec call */
|
|
if (!strcmp(name, "execve")) {
|
|
void *addr;
|
|
char *argname, before[MAXPATHLEN];
|
|
|
|
icpid->execve_code = code;
|
|
icpid->policynr = policynr;
|
|
|
|
if (icpid->newname)
|
|
free(icpid->newname);
|
|
|
|
intercept.getarg(0, args, argsize, &addr);
|
|
|
|
argname = intercept_filename(fd, pid, addr, ICLINK_ALL, before);
|
|
if (argname == NULL)
|
|
err(1, "%s:%d: intercept_filename",
|
|
__func__, __LINE__);
|
|
|
|
if (intercept.scriptname(fd, pid, before) != 0)
|
|
err(1, "%s:%d: ioctl", __func__, __LINE__);
|
|
|
|
icpid->newname = strdup(argname);
|
|
if (icpid->newname == NULL)
|
|
err(1, "%s:%d: strdup", __func__, __LINE__);
|
|
|
|
/* We need to know the result from this system call */
|
|
flags = ICFLAGS_RESULT;
|
|
}
|
|
|
|
icpid->elevate = NULL;
|
|
|
|
sc = intercept_sccb_find(emulation, name);
|
|
if (sc != NULL) {
|
|
struct intercept_translate *tl;
|
|
|
|
ic_abort = 0;
|
|
TAILQ_FOREACH(tl, &sc->tls, next) {
|
|
if (intercept_translate(tl, fd, pid, tl->off,
|
|
args, argsize) == -1)
|
|
break;
|
|
}
|
|
|
|
if (!ic_abort) {
|
|
struct intercept_replace repl;
|
|
|
|
intercept_replace_init(&repl);
|
|
|
|
action = (*sc->cb)(fd, pid, policynr, name, code,
|
|
emulation, args, argsize, &repl,
|
|
&sc->tls, sc->cb_arg);
|
|
|
|
if (action < ICPOLICY_NEVER) {
|
|
/* If we can not rewrite the arguments,
|
|
* system call fails.
|
|
*/
|
|
if (intercept_replace(fd, pid, seqnr, &repl) == -1)
|
|
action = ICPOLICY_NEVER;
|
|
}
|
|
} else
|
|
action = ICPOLICY_NEVER;
|
|
} else if (intercept_gencb != NULL)
|
|
action = (*intercept_gencb)(fd, pid, policynr, name, code,
|
|
emulation, args, argsize, intercept_gencbarg);
|
|
|
|
if (action > 0) {
|
|
error = action;
|
|
action = ICPOLICY_NEVER;
|
|
} else {
|
|
icpid = intercept_findpid(pid);
|
|
if (icpid != NULL)
|
|
elevate = icpid->elevate;
|
|
else
|
|
elevate = NULL;
|
|
}
|
|
|
|
|
|
/* Resume execution of the process */
|
|
intercept.answer(fd, pid, seqnr, action, error, flags, elevate);
|
|
}
|
|
|
|
void
|
|
intercept_syscall_result(int fd, pid_t pid, u_int16_t seqnr, int policynr,
|
|
const char *name, int code, const char *emulation, void *args, int argsize,
|
|
int result, void *rval)
|
|
{
|
|
struct intercept_pid *icpid;
|
|
|
|
if (result > 0)
|
|
goto out;
|
|
|
|
icpid = intercept_getpid(pid);
|
|
if (!strcmp("execve", name)) {
|
|
intercept_newimage(fd, pid, policynr, emulation,
|
|
icpid->newname, icpid);
|
|
/* we might have detached by now */
|
|
if (intercept_findpid(pid) == NULL)
|
|
return;
|
|
}
|
|
|
|
out:
|
|
/* Resume execution of the process */
|
|
intercept.answer(fd, pid, seqnr, 0, 0, 0, NULL);
|
|
}
|
|
|
|
void
|
|
intercept_newimage(int fd, pid_t pid, int policynr, const char *emulation,
|
|
char *newname, struct intercept_pid *icpid)
|
|
{
|
|
if (icpid == NULL)
|
|
icpid = intercept_getpid(pid);
|
|
|
|
if (icpid->name)
|
|
free(icpid->name);
|
|
if ((icpid->name = strdup(newname)) == NULL)
|
|
err(1, "%s:%d: strdup", __func__, __LINE__);
|
|
|
|
if (icpid->newname != NULL) {
|
|
free(icpid->newname);
|
|
icpid->newname = NULL;
|
|
}
|
|
|
|
if (intercept_newimagecb != NULL)
|
|
(*intercept_newimagecb)(fd, pid, policynr, emulation,
|
|
icpid->name, intercept_newimagecbarg);
|
|
|
|
}
|
|
|
|
int
|
|
intercept_newpolicy(int fd)
|
|
{
|
|
int policynr;
|
|
|
|
policynr = intercept.newpolicy(fd);
|
|
|
|
return (policynr);
|
|
}
|
|
|
|
int
|
|
intercept_assignpolicy(int fd, pid_t pid, int policynr)
|
|
{
|
|
return (intercept.assignpolicy(fd, pid, policynr));
|
|
}
|
|
|
|
int
|
|
intercept_modifypolicy(int fd, int policynr, const char *emulation,
|
|
const char *name, short policy)
|
|
{
|
|
int code;
|
|
|
|
code = intercept.getsyscallnumber(emulation, name);
|
|
if (code == -1)
|
|
return (-1);
|
|
|
|
return (intercept.policy(fd, policynr, code, policy));
|
|
}
|
|
|
|
void
|
|
intercept_child_info(pid_t opid, pid_t npid)
|
|
{
|
|
struct intercept_pid *ipid, *inpid, tmp;
|
|
|
|
/* A child just died on us */
|
|
if (npid == -1) {
|
|
intercept_freepid(opid);
|
|
return;
|
|
}
|
|
|
|
tmp.pid = opid;
|
|
ipid = SPLAY_FIND(pidtree, &pids, &tmp);
|
|
if (ipid == NULL)
|
|
return;
|
|
|
|
inpid = intercept_getpid(npid);
|
|
|
|
inpid->policynr = ipid->policynr;
|
|
if (ipid->name != NULL) {
|
|
inpid->name = strdup(ipid->name);
|
|
if (inpid->name == NULL)
|
|
err(1, "%s:%d: strdup", __func__, __LINE__);
|
|
}
|
|
|
|
/* Process tree */
|
|
inpid->ppid = opid;
|
|
|
|
/* Copy some information */
|
|
inpid->uid = ipid->uid;
|
|
inpid->gid = ipid->gid;
|
|
strlcpy(inpid->username, ipid->username, sizeof(inpid->username));
|
|
strlcpy(inpid->home, ipid->home, sizeof(inpid->home));
|
|
|
|
/* XXX - keeps track of emulation */
|
|
intercept.clonepid(ipid, inpid);
|
|
}
|
|
|
|
void
|
|
intercept_ugid(struct intercept_pid *icpid, uid_t uid, gid_t gid)
|
|
{
|
|
/* Update current home dir */
|
|
if (icpid->uid != uid) {
|
|
struct passwd *pw;
|
|
|
|
if ((pw = getpwuid(uid)) == NULL) {
|
|
snprintf(icpid->username, sizeof(icpid->username),
|
|
"uid %d", uid);
|
|
strlcpy(icpid->home, "/", sizeof(icpid->home));
|
|
} else {
|
|
strlcpy(icpid->username, pw->pw_name,
|
|
sizeof(icpid->username));
|
|
strlcpy(icpid->home, pw->pw_dir, sizeof(icpid->home));
|
|
}
|
|
}
|
|
|
|
icpid->uid = uid;
|
|
icpid->gid = gid;
|
|
}
|
|
|
|
/*
|
|
* Checks if the given emulation has a certain system call.
|
|
* This is a very slow function.
|
|
*/
|
|
|
|
int
|
|
intercept_isvalidsystemcall(char *emulation, char *name)
|
|
{
|
|
int res;
|
|
|
|
res = intercept.getsyscallnumber(emulation, name);
|
|
|
|
return (res != -1);
|
|
}
|
|
|
|
/*
|
|
* Call back when a user has exhausted the number of allowed policies
|
|
* in the kernel. The kernel returns the policy number of a policy
|
|
* that has been purged.
|
|
*/
|
|
|
|
void
|
|
intercept_policy_free(int policynr)
|
|
{
|
|
(*intercept_pfreecb)(policynr, intercept_pfreearg);
|
|
}
|