[LibOS] Don't use insecure random

LibOS/shim/include/shim_internal.h

@@ -785,7 +785,6 @@ static_always_inline void * current_stack(void)
 
 void get_brk_region (void ** start, void ** end, void ** current);
 
-int init_randgen (void);
 int reset_brk (void);
 int init_brk_region (void * brk_region);
 int init_heap (void);

LibOS/shim/include/shim_utils.h

@@ -208,9 +208,6 @@ void md5_final (struct shim_md5_ctx * mdContext);
 /* prompt user for confirmation */
 int message_confirm (const char * message, const char * options);
 
-/* get random bytes (not for crypto!) */
-void getrand (void * buffer, size_t size);
-
 /* ELF binary loading */
 int check_elf_object (struct shim_handle * file);
 int load_elf_object (struct shim_handle * file, void * addr, size_t mapped);

LibOS/shim/src/Makefile

@@ -50,7 +50,7 @@ objs	= $(addprefix bookkeep/shim_,handle vma thread signal) \
 	  $(addprefix ipc/shim_,ipc ipc_helper ipc_child) \
 	  $(addprefix ipc/shim_ipc_,$(ipcns)) \
 	  elf/shim_rtld \
-	  $(addprefix shim_,init table syscalls checkpoint random malloc \
+	  $(addprefix shim_,init table syscalls checkpoint malloc \
 	  async parser debug) syscallas start \
 	  $(patsubst %.c,%,$(wildcard sys/*.c))
 graphene_lib = .lib/graphene-lib.a

LibOS/shim/src/bookkeep/shim_vma.c

@@ -342,7 +342,7 @@ int init_vma (void)
     uint64_t addr_rand_size =
         (PAL_CB(user_address.end) - PAL_CB(user_address.start)) * 5 / 6;
     uint64_t rand;
-    getrand(&rand, sizeof(rand));
+    DkRandomBitsRead(&rand, sizeof(rand));
     current_heap_top -= ALIGN_DOWN(rand % addr_rand_size);
 #endif
 

LibOS/shim/src/fs/dev/fs.c

@@ -117,16 +117,13 @@ static int dev_random_mode (const char * name, mode_t * mode)
 static int dev_random_read (struct shim_handle * hdl, void * buf,
                             size_t count)
 {
-    int rv = DkRandomBitsRead(buf, count);
-    return rv;
+    return DkRandomBitsRead(buf, count);
 }
 
 static int dev_urandom_read (struct shim_handle * hdl, void * buf,
                              size_t count)
 {
-    // THIS IS NOT CRYPTO-SECURE, FIX!!!
-    getrand(buf, count);
-    return count;
+    return DkRandomBitsRead(buf, count);
 }
 
 static int dev_random_stat (const char * name, struct stat * stat)

LibOS/shim/src/shim_init.c

@@ -636,7 +636,6 @@ DEFINE_PROFILE_INTERVAL(pal_tail_startup_time,          pal);
 DEFINE_PROFILE_INTERVAL(pal_child_creation_time,        pal);
 
 DEFINE_PROFILE_CATAGORY(init, );
-DEFINE_PROFILE_INTERVAL(init_randgen,               init);
 DEFINE_PROFILE_INTERVAL(init_vma,                   init);
 DEFINE_PROFILE_INTERVAL(init_slab,                  init);
 DEFINE_PROFILE_INTERVAL(init_str_mgr,               init);
@@ -725,7 +724,6 @@ int shim_init (int argc, void * args, void ** return_stack)
 #endif
 
     BEGIN_PROFILE_INTERVAL();
-    RUN_INIT(init_randgen);
     RUN_INIT(init_vma);
     RUN_INIT(init_slab);
     RUN_INIT(read_environs, envp);
@@ -862,7 +860,7 @@ static int name_pipe (char * uri, size_t size, void * id)
 {
     IDTYPE pipeid;
     int len;
-    getrand(&pipeid, sizeof(pipeid));
+    DkRandomBitsRead(&pipeid, sizeof(pipeid));
     debug("creating pipe: pipe.srv:%u\n", pipeid);
     if ((len = snprintf(uri, size, "pipe.srv:%u", pipeid)) == size)
         return -ERANGE;
@@ -911,7 +909,7 @@ static int name_path (char * path, size_t size, void * id)
     unsigned int suffix;
     int prefix_len = strlen(path);
     int len;
-    getrand(&suffix, sizeof(suffix));
+    DkRandomBitsRead(&suffix, sizeof(suffix));
     len = snprintf(path + prefix_len, size - prefix_len, "%08x", suffix);
     if (len == size)
         return -ERANGE;

LibOS/shim/src/shim_random.c

@@ -1,63 +0,0 @@
-/* -*- mode:c; c-file-style:"k&r"; c-basic-offset: 4; tab-width:4; indent-tabs-mode:nil; mode:auto-fill; fill-column:78; -*- */
-/* vim: set ts=4 sw=4 et tw=78 fo=cqt wm=0: */
-
-/* Copyright (C) 2014 Stony Brook University
-   This file is part of Graphene Library OS.
-
-   Graphene Library OS is free software: you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public License
-   as published by the Free Software Foundation, either version 3 of the
-   License, or (at your option) any later version.
-
-   Graphene Library OS is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU Lesser General Public License for more details.
-
-   You should have received a copy of the GNU Lesser General Public License
-   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
-
-/*
- * shim_random.c
- *
- * This file contains codes for generating random numbers.
- */
-
-#include <shim_internal.h>
-#include <shim_utils.h>
-#include <shim_checkpoint.h>
-
-#include <pal.h>
-
-static LOCKTYPE randgen_lock;
-static unsigned long randval;
-
-int init_randgen (void)
-{
-    if (DkRandomBitsRead (&randval, sizeof(randval)) < sizeof(randval))
-        return -EACCES;
-
-    debug("initial random value: %08lx\n", randval);
-    create_lock(randgen_lock);
-    return 0;
-}
-
-void getrand (void * buffer, size_t size)
-{
-    size_t bytes = 0;
-    lock(randgen_lock);
-
-    while (bytes + sizeof(uint64_t) <= size) {
-        *(uint64_t *) (buffer + bytes) = randval;
-        bytes += sizeof(uint64_t);
-        randval = hash64(randval);
-    }
-
-    if (bytes < size) {
-        memcpy(buffer + bytes, &randval, size - bytes);
-        randval = hash64(randval);
-    }
-
-    unlock(randgen_lock);
-}
-extern_alias(getrand);

LibOS/shim/src/sys/shim_brk.c

@@ -85,7 +85,7 @@ int init_brk_region (void * brk_region)
     if (brk_region) {
         while (true) {
             uint32_t rand;
-            getrand(&rand, sizeof(rand));
+            DkRandomBitsRead(&rand, sizeof(rand));
             rand %= 0x2000000;
             rand = ALIGN_UP(rand);
 

LibOS/shim/src/sys/shim_migrate.c

@@ -113,7 +113,7 @@ int create_checkpoint (const char * cpdir, IDTYPE * sid)
             }
     } else {
 retry:
-        getrand(&cpsession->sid, sizeof(IDTYPE));
+        DkRandomBitsRead(&cpsession->sid, sizeof(cpsession->sid));
 
         listp_for_each_entry(s, &cp_sessions, list)
             if (s->sid == cpsession->sid)

Pal/src/host/FreeBSD/db_misc.c

@@ -184,52 +184,6 @@ int _DkInstructionCacheFlush (const void * addr, int size)
 {
     return -PAL_ERROR_NOTIMPLEMENTED;
 }
-static PAL_LOCK lock = LOCK_INIT;
-static unsigned long randval = 0;
-
-static int init_randgen (void)
-{
-    unsigned long val;
-
-    if (_DkRandomBitsRead(&val, sizeof(val)) < sizeof(val))
-        return -PAL_ERROR_DENIED;
-
-    _DkInternalLock(&lock);
-    randval = val;
-    _DkInternalUnlock(&lock);
-    return 0;
-}
-
-int getrand (void * buffer, size_t size)
-{
-    unsigned long val;
-    size_t bytes = 0;
-
-    int ret = init_randgen();
-    if (ret < 0)
-        return ret;
-
-    _DkInternalLock(&lock);
-    val = randval;
-    randval = hash64(~randval);
-    _DkInternalUnlock(&lock);
-
-    while (bytes + sizeof(uint64_t) <= size) {
-        *(uint64_t *) (buffer + bytes) = val;
-        val = hash64(val);
-        bytes += sizeof(uint64_t);
-    }
-
-    if (bytes < size) {
-        memcpy(buffer + bytes, &val, size - bytes);
-        val = hash64(val);
-    }
-
-    _DkInternalLock(&lock);
-    randval = val;
-    _DkInternalUnlock(&lock);
-    return 0;
-}
 
 int _DkCpuIdRetrieve (unsigned int leaf, unsigned int subleaf,
                       unsigned int values[4])

Pal/src/host/FreeBSD/pal_freebsd.h

@@ -47,8 +47,6 @@ typedef int __kernel_pid_t;
 #define ERRNO INTERNAL_SYSCALL_ERRNO
 #define ERRNO_P INTERNAL_SYSCALL_ERRNO_P
 
-int getrand (void * buffer, size_t size);
-
 struct timespec;
 struct timeval;
 extern struct pal_bsd_state {