xnu-2782.20.48.tar.gz

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

diff --git a/bsd/kern/mach_loader.c b/bsd/kern/mach_loader.c
index c590c52d69bc06494792ba87eba176923935575a..0f477bdf07927899dd8b4e6e4c62ce11d91f58da 100644 (file)
--- a/bsd/kern/mach_loader.c
+++ b/bsd/kern/mach_loader.c
@@ -113,7 +113,8 @@ static load_result_t load_result_null = {
        .csflags = 0,
        .uuid = { 0 },
        .min_vm_addr = MACH_VM_MAX_ADDRESS,
-       .max_vm_addr = MACH_VM_MIN_ADDRESS
+       .max_vm_addr = MACH_VM_MIN_ADDRESS,
+       .cs_end_offset = 0
 };
 
 /*
@@ -772,6 +773,37 @@ parse_machfile(
                                } else {
                                        got_code_signatures = TRUE;
                                }
+
+                               if (got_code_signatures) {
+                                       boolean_t valid = FALSE, tainted = TRUE;
+                                       struct cs_blob *blobs;
+                                       vm_size_t off = 0;
+
+
+                                       if (cs_debug > 10)
+                                               printf("validating initial pages of %s\n", vp->v_name);
+                                       blobs = ubc_get_cs_blobs(vp);
+                                       
+                                       while (off < size && ret == LOAD_SUCCESS) {
+                                            valid = cs_validate_page(blobs,
+                                                                     NULL,
+                                                                     file_offset + off,
+                                                                     addr + off,
+                                                                     &tainted);
+                                            if (!valid || tainted) {
+                                                    if (cs_debug)
+                                                            printf("CODE SIGNING: %s[%d]: invalid initial page at offset %lld validated:%d tainted:%d csflags:0x%x\n", 
+                                                                   vp->v_name, p->p_pid, (long long)(file_offset + off), valid, tainted, result->csflags);
+                                                    if (cs_enforcement(NULL) ||
+                                                        (result->csflags & (CS_HARD|CS_KILL|CS_ENFORCEMENT))) {
+                                                            ret = LOAD_FAILURE;
+                                                    }
+                                                    result->csflags &= ~CS_VALID;
+                                            }
+                                            off += PAGE_SIZE;
+                                       }
+                               }
+
                                break;
 #if CONFIG_CODE_DECRYPTION
                        case LC_ENCRYPTION_INFO:
@@ -991,6 +1023,20 @@ load_segment(
        if ((scp->fileoff & PAGE_MASK_64) != 0)
                return (LOAD_BADMACHO);
 
+       /*
+        * If we have a code signature attached for this slice
+        * require that the segments are within the signed part
+        * of the file.
+        */
+       if (result->cs_end_offset &&
+           result->cs_end_offset < (off_t)scp->fileoff &&
+           result->cs_end_offset - scp->fileoff < scp->filesize)
+        {
+               if (cs_debug)
+                       printf("section outside code signature\n");
+               return LOAD_BADMACHO;
+       }
+
        /*
         *      Round sizes to page size.
         */
@@ -1290,25 +1336,46 @@ load_threadstate(
        uint32_t        size;
        int             flavor;
        uint32_t        thread_size;
+       uint32_t        *local_ts;
+       uint32_t        local_ts_size;
 
-    ret = thread_state_initialize( thread );
-    if (ret != KERN_SUCCESS) {
-        return(LOAD_FAILURE);
-    }
+       local_ts = NULL;
+       local_ts_size = 0;
+
+       ret = thread_state_initialize( thread );
+       if (ret != KERN_SUCCESS) {
+               ret = LOAD_FAILURE;
+               goto done;
+       }
     
+       if (total_size > 0) {
+               local_ts_size = total_size;
+               local_ts = kalloc(local_ts_size);
+               if (local_ts == NULL) {
+                       ret = LOAD_FAILURE;
+                       goto done;
+               }
+               memcpy(local_ts, ts, local_ts_size);
+               ts = local_ts;
+       }
+
        /*
-        *      Set the new thread state; iterate through the state flavors in
-     *  the mach-o file.
+        * Set the new thread state; iterate through the state flavors in
+        * the mach-o file.
         */
        while (total_size > 0) {
                flavor = *ts++;
                size = *ts++;
                if (UINT32_MAX-2 < size ||
-                   UINT32_MAX/sizeof(uint32_t) < size+2)
-                       return (LOAD_BADMACHO);
+                   UINT32_MAX/sizeof(uint32_t) < size+2) {
+                       ret = LOAD_BADMACHO;
+                       goto done;
+               }
                thread_size = (size+2)*sizeof(uint32_t);
-               if (thread_size > total_size)
-                       return(LOAD_BADMACHO);
+               if (thread_size > total_size) {
+                       ret = LOAD_BADMACHO;
+                       goto done;
+               }
                total_size -= thread_size;
                /*
                 * Third argument is a kernel space pointer; it gets cast
@@ -1317,11 +1384,19 @@ load_threadstate(
                 */
                ret = thread_setstatus(thread, flavor, (thread_state_t)ts, size);
                if (ret != KERN_SUCCESS) {
-                       return(LOAD_FAILURE);
+                       ret = LOAD_FAILURE;
+                       goto done;
                }
                ts += size;     /* ts is a (uint32_t *) */
        }
-       return(LOAD_SUCCESS);
+       ret = LOAD_SUCCESS;
+
+done:
+       if (local_ts != NULL) {
+               kfree(local_ts, local_ts_size);
+               local_ts = NULL;
+       }
+       return ret;
 }
 
 static
@@ -1584,7 +1659,7 @@ load_code_signature(
                goto out;
        }
 
-       blob = ubc_cs_blob_get(vp, cputype, -1);
+       blob = ubc_cs_blob_get(vp, cputype, macho_offset);
        if (blob != NULL) {
                /* we already have a blob for this vnode and cputype */
                if (blob->csb_cpu_type == cputype &&
@@ -1644,13 +1719,14 @@ load_code_signature(
        ubc_cs_validation_bitmap_allocate( vp );
 #endif
                
-       blob = ubc_cs_blob_get(vp, cputype, -1);
+       blob = ubc_cs_blob_get(vp, cputype, macho_offset);
 
        ret = LOAD_SUCCESS;
 out:
        if (ret == LOAD_SUCCESS) {
                result->csflags |= blob->csb_flags;
                result->platform_binary = blob->csb_platform_binary;
+               result->cs_end_offset = blob->csb_end_offset;
        }
        if (addr != 0) {
                ubc_cs_blob_deallocate(addr, blob_size);