xnu-4570.51.1.tar.gz

[apple/xnu.git] / bsd / dev / dtrace / dtrace_subr.c

diff --git a/bsd/dev/dtrace/dtrace_subr.c b/bsd/dev/dtrace/dtrace_subr.c
index aa8fb6c1a36ac4441652665b140cf29225e2b79a..3bc601af83d994c97eb0219fb394510ef0cee11c 100644 (file)
--- a/bsd/dev/dtrace/dtrace_subr.c
+++ b/bsd/dev/dtrace/dtrace_subr.c
@@ -35,6 +35,7 @@
 #include <sys/dtrace.h>
 #include <sys/dtrace_impl.h>
 #include <sys/proc_internal.h>
 #include <sys/dtrace.h>
 #include <sys/dtrace_impl.h>
 #include <sys/proc_internal.h>

+#include <sys/vnode.h>

 #include <kern/debug.h>
 #include <kern/sched_prim.h>
 #include <kern/task.h>
 #include <kern/debug.h>
 #include <kern/sched_prim.h>
 #include <kern/task.h>


@@ -119,9 +120,40 @@ LIST_HEAD(listhead, dtrace_proc_awaited_entry) dtrace_proc_awaited_head
 
 void (*dtrace_proc_waitfor_exec_ptr)(proc_t*) = NULL;
 
 
 void (*dtrace_proc_waitfor_exec_ptr)(proc_t*) = NULL;
 

+static int
+dtrace_proc_get_execpath(proc_t *p, char *buffer, int *maxlen)
+{
+       int err = 0, vid = 0;
+       vnode_t tvp = NULLVP, nvp = NULLVP;
+
+       ASSERT(p);
+       ASSERT(buffer);
+       ASSERT(maxlen);
+
+       if ((tvp = p->p_textvp) == NULLVP)
+               return ESRCH;
+
+       vid = vnode_vid(tvp);
+       if ((err = vnode_getwithvid(tvp, vid)) != 0)
+               return err;
+
+       if ((err = vn_getpath_fsenter(tvp, buffer, maxlen)) != 0)
+               return err;
+       vnode_put(tvp);
+
+       if ((err = vnode_lookup(buffer, 0, &nvp, vfs_context_current())) != 0)
+               return err;
+       if (nvp != NULLVP)
+               vnode_put(nvp);
+
+       return 0;
+}
+
+

 static void
 dtrace_proc_exec_notification(proc_t *p) {
        dtrace_proc_awaited_entry_t *entry, *tmp;
 static void
 dtrace_proc_exec_notification(proc_t *p) {
        dtrace_proc_awaited_entry_t *entry, *tmp;

+       static char execpath[MAXPATHLEN];

 
        ASSERT(p);
        ASSERT(p->p_pid != -1);
 
        ASSERT(p);
        ASSERT(p->p_pid != -1);


@@ -129,16 +161,31 @@ dtrace_proc_exec_notification(proc_t *p) {
 
        lck_mtx_lock(&dtrace_procwaitfor_lock);
 
 
        lck_mtx_lock(&dtrace_procwaitfor_lock);
 

-       /*
-        * For each entry, if it has not been matched with a process yet we
-        * try to match it with the newly created process. If they match, the
-        * entry is initialized with the process id and the process task is
-        * suspended. Finally, we wake up the client's waiting thread.
-        */

        LIST_FOREACH_SAFE(entry, &dtrace_proc_awaited_head, entries, tmp) {
        LIST_FOREACH_SAFE(entry, &dtrace_proc_awaited_head, entries, tmp) {

-               if ((entry->pdesc->p_pid == -1)
-                   && !strncmp(entry->pdesc->p_comm, &p->p_comm[0], sizeof(p->p_comm)))
-               {
+               /* By default consider we're using p_comm. */
+               char *pname = p->p_comm;
+
+               /* Already matched with another process. */
+               if ((entry->pdesc->p_pid != -1))
+                       continue;
+
+               /* p_comm is too short, use the execpath. */
+               if (entry->pdesc->p_name_length >= MAXCOMLEN) {
+                       /*
+                        * Retrieve the executable path. After the call, length contains
+                        * the length of the string + 1.
+                        */
+                       int length = sizeof(execpath);
+                       if (dtrace_proc_get_execpath(p, execpath, &length) != 0)
+                               continue;
+                       /* Move the cursor to the position after the last / */
+                       pname = &execpath[length - 1];
+                       while (pname != execpath && *pname != '/')
+                               pname--;
+                       pname = (*pname == '/') ? pname + 1 : pname;
+               }
+
+               if (!strcmp(entry->pdesc->p_name, pname)) {

                        entry->pdesc->p_pid = p->p_pid;
                        task_pidsuspend(p->task);
                        wakeup(entry);
                        entry->pdesc->p_pid = p->p_pid;
                        task_pidsuspend(p->task);
                        wakeup(entry);


@@ -154,7 +201,15 @@ dtrace_proc_waitfor(dtrace_procdesc_t* pdesc) {
        int res;
 
        ASSERT(pdesc);
        int res;
 
        ASSERT(pdesc);

-       ASSERT(pdesc->p_comm);
+       ASSERT(pdesc->p_name);
+
+       /*
+        * Never trust user input, compute the length of the process name and ensure the
+        * string is null terminated.
+        */
+       pdesc->p_name_length = strnlen(pdesc->p_name, sizeof(pdesc->p_name));
+       if (pdesc->p_name_length >= (int) sizeof(pdesc->p_name))
+               return -1;

 
        lck_mtx_lock(&dtrace_procwaitfor_lock);
 
 
        lck_mtx_lock(&dtrace_procwaitfor_lock);
 


@@ -240,6 +295,55 @@ dtrace_invop_remove(int (*func)(uintptr_t, uintptr_t *, uintptr_t))
        kmem_free(hdlr, sizeof (dtrace_invop_hdlr_t));
 }
 
        kmem_free(hdlr, sizeof (dtrace_invop_hdlr_t));
 }
 

+static minor_t next_minor = 0;
+static dtrace_state_t* dtrace_clients[DTRACE_NCLIENTS] = {NULL};
+
+
+minor_t
+dtrace_state_reserve(void)
+{
+       for (int i = 0; i < DTRACE_NCLIENTS; i++) {
+               minor_t minor = atomic_add_32(&next_minor, 1) % DTRACE_NCLIENTS;
+               if (dtrace_clients[minor] == NULL)
+                       return minor;
+       }
+       return 0;
+}
+
+dtrace_state_t*
+dtrace_state_get(minor_t minor)
+{
+       ASSERT(minor < DTRACE_NCLIENTS);
+       return dtrace_clients[minor];
+}
+
+dtrace_state_t*
+dtrace_state_allocate(minor_t minor)
+{
+       dtrace_state_t *state = _MALLOC(sizeof(dtrace_state_t), M_TEMP, M_ZERO | M_WAITOK);
+       if (dtrace_casptr(&dtrace_clients[minor], NULL, state) != NULL) {
+               // We have been raced by another client for this number, abort
+               _FREE(state, M_TEMP);
+               return NULL;
+       }
+       return state;
+}
+
+void
+dtrace_state_free(minor_t minor)
+{
+       dtrace_state_t *state = dtrace_clients[minor];
+       dtrace_clients[minor] = NULL;
+       _FREE(state, M_TEMP);
+}
+
+
+
+void
+dtrace_restriction_policy_load(void)
+{
+}
+

 /*
  * Check if DTrace has been restricted by the current security policy.
  */
 /*
  * Check if DTrace has been restricted by the current security policy.
  */


@@ -254,6 +358,36 @@ dtrace_is_restricted(void)
        return FALSE;
 }
 
        return FALSE;
 }
 

+boolean_t
+dtrace_are_restrictions_relaxed(void)
+{
+#if CONFIG_CSR
+       if (csr_check(CSR_ALLOW_APPLE_INTERNAL) == 0)
+               return TRUE;
+#endif
+
+       return FALSE;
+}
+
+boolean_t
+dtrace_fbt_probes_restricted(void)
+{
+
+#if CONFIG_CSR
+       if (dtrace_is_restricted() && !dtrace_are_restrictions_relaxed())
+               return TRUE;
+#endif
+
+       return FALSE;
+}
+
+boolean_t
+dtrace_sdt_probes_restricted(void)
+{
+
+       return FALSE;
+}
+

 /*
  * Check if the process can be attached.
  */
 /*
  * Check if the process can be attached.
  */


@@ -264,7 +398,7 @@ dtrace_can_attach_to_proc(proc_t *proc)
        ASSERT(proc != NULL);
 
 #if CONFIG_CSR
        ASSERT(proc != NULL);
 
 #if CONFIG_CSR

-       if ((cs_entitlement_flags(proc) & CS_GET_TASK_ALLOW) == 0)
+       if (cs_restricted(proc))

                return FALSE;
 #endif
 
                return FALSE;
 #endif