xnu-2782.40.9.tar.gz

[apple/xnu.git] / bsd / kern / mach_process.c

diff --git a/bsd/kern/mach_process.c b/bsd/kern/mach_process.c
index 46d527f0507b75b7142306f3467f747ff79fcf6e..ef8ebffcd60e29d96e328c2174dea826a31a4f3f 100644 (file)
--- a/bsd/kern/mach_process.c
+++ b/bsd/kern/mach_process.c
@@ -82,8 +82,10 @@
 
 #include <sys/mount_internal.h>
 #include <sys/sysproto.h>
+#include <sys/kdebug.h>
+#include <sys/codesign.h>              /* cs_allow_invalid() */
 
-#include <bsm/audit_kernel.h>
+#include <security/audit/audit.h>
 
 #include <kern/task.h>
 #include <kern/thread.h>
@@ -91,6 +93,8 @@
 #include <mach/task.h>                 /* for task_resume() */
 #include <kern/sched_prim.h>           /* for thread_exception_return() */
 
+#include <pexpert/pexpert.h>
+
 /* XXX ken/bsd_kern.c - prototype should be in common header */
 int get_task_userstop(task_t);
 
@@ -108,7 +112,7 @@ extern thread_t get_firstthread(task_t);
  */
 
 int
-ptrace(struct proc *p, struct ptrace_args *uap, register_t *retval)
+ptrace(struct proc *p, struct ptrace_args *uap, int32_t *retval)
 {
        struct proc *t = current_proc();        /* target process */
        task_t          task;
@@ -121,14 +125,16 @@ ptrace(struct proc *p, struct ptrace_args *uap, register_t *retval)
        AUDIT_ARG(cmd, uap->req);
        AUDIT_ARG(pid, uap->pid);
        AUDIT_ARG(addr, uap->addr);
-       AUDIT_ARG(value, uap->data);
+       AUDIT_ARG(value32, uap->data);
 
        if (uap->req == PT_DENY_ATTACH) {
                proc_lock(p);
                if (ISSET(p->p_lflag, P_LTRACED)) {
                        proc_unlock(p);
+                       KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_FRCEXIT) | DBG_FUNC_NONE,
+                                             p->p_pid, W_EXITCODE(ENOTSUP, 0), 4, 0, 0);
                        exit1(p, W_EXITCODE(ENOTSUP, 0), retval);
-                       /* drop funnel before we return */
+
                        thread_exception_return();
                        /* NOTREACHED */
                }
@@ -139,8 +145,8 @@ ptrace(struct proc *p, struct ptrace_args *uap, register_t *retval)
        }
 
        if (uap->req == PT_FORCEQUOTA) {
-               if (is_suser()) {
-                       OSBitOrAtomic(P_FORCEQUOTA, (UInt32 *)&t->p_flag);
+               if (kauth_cred_issuser(kauth_cred_get())) {
+                       OSBitOrAtomic(P_FORCEQUOTA, &t->p_flag);
                        return (0);
                } else
                        return (EPERM);
@@ -154,7 +160,15 @@ ptrace(struct proc *p, struct ptrace_args *uap, register_t *retval)
                SET(p->p_lflag, P_LTRACED);
                /* Non-attached case, our tracer is our parent. */
                p->p_oppid = p->p_ppid;
+               /* Check whether child and parent are allowed to run modified
+                * code (they'll have to) */
+               struct proc *pproc=proc_find(p->p_oppid);
                proc_unlock(p);
+               cs_allow_invalid(p);
+               if(pproc) {
+                       cs_allow_invalid(pproc);
+                       proc_rele(pproc);
+               }
                return(0);
        }
        if (uap->req == PT_SIGEXC) {
@@ -201,7 +215,11 @@ ptrace(struct proc *p, struct ptrace_args *uap, register_t *retval)
                                SET(t->p_lflag, P_LSIGEXC);
        
                        t->p_oppid = t->p_ppid;
+                       /* Check whether child and parent are allowed to run modified
+                        * code (they'll have to) */
                        proc_unlock(t);
+                       cs_allow_invalid(t);
+                       cs_allow_invalid(p);
                        if (t->p_pptr != p)
                                proc_reparentlocked(t, p, 1, 0);
        
@@ -275,11 +293,17 @@ ptrace(struct proc *p, struct ptrace_args *uap, register_t *retval)
 
                        proc_unlock(t);
                        pp = proc_find(t->p_oppid);
-                       proc_reparentlocked(t, pp ? pp : initproc, 1, 0);
-                       if (pp != PROC_NULL)
+                       if (pp != PROC_NULL) {
+                               proc_reparentlocked(t, pp, 1, 0);
                                proc_rele(pp);
+                       } else {
+                               /* original parent exited while traced */
+                               proc_list_lock();
+                               t->p_listflag |= P_LIST_DEADPARENT;
+                               proc_list_unlock();
+                               proc_reparentlocked(t, initproc, 1, 0);
+                       }
                        proc_lock(t);
-                       
                }
 
                t->p_oppid = 0;
@@ -294,6 +318,11 @@ ptrace(struct proc *p, struct ptrace_args *uap, register_t *retval)
                 *      is resumed by adding NSIG to p_cursig. [see issig]
                 */
                proc_unlock(t);
+#if CONFIG_MACF
+               error = mac_proc_check_signal(p, t, SIGKILL);
+               if (0 != error)
+                       goto resume;
+#endif
                psignal(t, SIGKILL);
                goto resume;
 
@@ -306,14 +335,10 @@ ptrace(struct proc *p, struct ptrace_args *uap, register_t *retval)
                        goto out;
                }
 
+               /* force use of Mach SPIs (and task_for_pid security checks) to adjust PC */
                if (uap->addr != (user_addr_t)1) {
-#if defined(ppc)
-#define ALIGNED(addr,size)     (((unsigned)(addr)&((size)-1))==0)
-                       if (!ALIGNED((int)uap->addr, sizeof(int)))
-                               return (ERESTART);
-#undef         ALIGNED
-#endif
-                       thread_setentrypoint(th_act, uap->addr);
+                       error = ENOTSUP;
+                       goto out;
                }
 
                if ((unsigned)uap->data >= NSIG) {
@@ -327,8 +352,15 @@ ptrace(struct proc *p, struct ptrace_args *uap, register_t *retval)
 
                if (uap->req == PT_STEP) {
                        /*
-                        * set trace bit
+                        * set trace bit 
+                        * we use sending SIGSTOP as a comparable security check.
                         */
+#if CONFIG_MACF
+                       error = mac_proc_check_signal(p, t, SIGSTOP);
+                       if (0 != error) {
+                               goto out;
+                       }
+#endif
                        if (thread_setsinglestep(th_act, 1) != KERN_SUCCESS) {
                                error = ENOTSUP;
                                goto out;
@@ -336,7 +368,14 @@ ptrace(struct proc *p, struct ptrace_args *uap, register_t *retval)
                } else {
                        /*
                         * clear trace bit if on
+                        * we use sending SIGCONT as a comparable security check.
                         */
+#if CONFIG_MACF
+                       error = mac_proc_check_signal(p, t, SIGCONT);
+                       if (0 != error) {
+                               goto out;
+                       }
+#endif
                        if (thread_setsinglestep(th_act, 0) != KERN_SUCCESS) {
                                error = ENOTSUP;
                                goto out;
@@ -363,7 +402,7 @@ ptrace(struct proc *p, struct ptrace_args *uap, register_t *retval)
                        error = EINVAL;
                        goto out;
                }
-               th_act = port_name_to_thread(CAST_DOWN(mach_port_name_t, uap->addr));
+               th_act = port_name_to_thread(CAST_MACH_PORT_TO_NAME(uap->addr));
                if (th_act == THREAD_NULL)
                        return (ESRCH);
                ut = (uthread_t)get_bsdthread_info(th_act);
@@ -419,7 +458,7 @@ cantrace(proc_t cur_procp, kauth_cred_t creds, proc_t traced_procp, int *errp)
         *      (3) it's not owned by you, or is set-id on exec
         *          (unless you're root).
         */
-       if ((creds->cr_ruid != proc_ucred(traced_procp)->cr_ruid ||
+       if ((kauth_cred_getruid(creds) != kauth_cred_getruid(proc_ucred(traced_procp)) ||
                ISSET(traced_procp->p_flag, P_SUGID)) &&
                (my_err = suser(creds, &cur_procp->p_acflag)) != 0) {
                *errp = my_err;
@@ -435,5 +474,13 @@ cantrace(proc_t cur_procp, kauth_cred_t creds, proc_t traced_procp, int *errp)
                *errp = EBUSY;
                return (0);
        }
+
+#if CONFIG_MACF
+       if ((my_err = mac_proc_check_debug(cur_procp, traced_procp)) != 0) {
+               *errp = my_err;
+               return (0);
+       }
+#endif
+
        return(1);
 }