Merge remote-tracking branch 'tor-github/pr/724'

changes/ticket29537

@@ -0,0 +1,3 @@
+  o Testing:
+    - Check that representative subsets of values of `int` and `unsigned int`
+      can be represented by `void *`. Resolves issue 29537.

configure.ac

@@ -1605,6 +1605,7 @@ AC_CHECK_MEMBERS([struct timeval.tv_sec], , ,
 AC_CHECK_SIZEOF(char)
 AC_CHECK_SIZEOF(short)
 AC_CHECK_SIZEOF(int)
+AC_CHECK_SIZEOF(unsigned int)
 AC_CHECK_SIZEOF(long)
 AC_CHECK_SIZEOF(long long)
 AC_CHECK_SIZEOF(__int64)

src/lib/cc/torint.h

@@ -125,4 +125,13 @@ typedef int32_t ssize_t;
 /** Any size_t larger than this amount is likely to be an underflow. */
 #define SIZE_T_CEILING  ((size_t)(SSIZE_MAX-16))
 
+#if SIZEOF_INT > SIZEOF_VOID_P
+#error "sizeof(int) > sizeof(void *) - Tor cannot be built on this platform!"
+#endif
+
+#if SIZEOF_UNSIGNED_INT > SIZEOF_VOID_P
+#error "sizeof(unsigned int) > sizeof(void *) - Tor cannot be built on this \
+platform!"
+#endif
+
 #endif /* !defined(TOR_TORINT_H) */

src/test/include.am

@@ -211,6 +211,8 @@ src_test_test_slow_SOURCES += \
 	src/test/test_crypto_slow.c \
 	src/test/test_process_slow.c \
 	src/test/test_prob_distr.c \
+	src/test/ptr_helpers.c \
+	src/test/test_ptr_slow.c \
 	src/test/testing_common.c \
 	src/test/testing_rsakeys.c \
 	src/ext/tinytest.c
@@ -314,6 +316,7 @@ noinst_HEADERS+= \
 	src/test/log_test_helpers.h \
 	src/test/rend_test_helpers.h \
 	src/test/test.h \
+	src/test/ptr_helpers.h \
 	src/test/test_helpers.h \
 	src/test/test_dir_common.h \
 	src/test/test_connection.h \

src/test/ptr_helpers.c

@@ -0,0 +1,50 @@
+/* Copyright (c) 2001-2004, Roger Dingledine.
+ * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
+ * Copyright (c) 2007-2019, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+#include "ptr_helpers.h"
+
+/**
+ * Cast <b> (inptr_t value) to a void pointer.
+ */
+void *
+cast_intptr_to_voidstar(intptr_t x)
+{
+  void *r = (void *)x;
+
+  return r;
+}
+
+/**
+ * Cast x (void pointer) to inptr_t value.
+ */
+intptr_t
+cast_voidstar_to_intptr(void *x)
+{
+  intptr_t r = (intptr_t)x;
+
+  return r;
+}
+
+/**
+ * Cast x (uinptr_t value) to void pointer.
+ */
+void *
+cast_uintptr_to_voidstar(uintptr_t x)
+{
+  void *r = (void *)x;
+
+  return r;
+}
+
+/**
+ * Cast x (void pointer) to uinptr_t value.
+ */
+uintptr_t
+cast_voidstar_to_uintptr(void *x)
+{
+  uintptr_t r = (uintptr_t)x;
+
+  return r;
+}

src/test/ptr_helpers.h

@@ -0,0 +1,23 @@
+/* Copyright (c) 2001-2004, Roger Dingledine.
+ * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
+ * Copyright (c) 2007-2019, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+#ifndef TOR_PTR_HELPERS_H
+#define TOR_PTR_HELPERS_H
+
+#include <stdint.h>
+
+void *
+cast_intptr_to_voidstar(intptr_t x);
+
+intptr_t
+cast_voidstar_to_intptr(void *x);
+
+void *
+cast_uintptr_to_voidstar(uintptr_t x);
+
+uintptr_t
+cast_voidstar_to_uintptr(void *x);
+
+#endif

src/test/test.h

@@ -278,6 +278,7 @@ extern struct testcase_t x509_tests[];
 
 extern struct testcase_t slow_crypto_tests[];
 extern struct testcase_t slow_process_tests[];
+extern struct testcase_t slow_ptr_tests[];
 
 extern struct testgroup_t testgroups[];
 

src/test/test_ptr_slow.c

@@ -0,0 +1,106 @@
+/* Copyright (c) 2001-2004, Roger Dingledine.
+ * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
+ * Copyright (c) 2007-2019, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+#include "orconfig.h"
+#include "core/or/or.h"
+#include "test/test.h"
+#include "test/ptr_helpers.h"
+
+#include <stdint.h>
+#include <limits.h>
+
+/** Assert that <b>a</b> can be cast to void * and back. */
+static void
+assert_int_voidptr_roundtrip(int a)
+{
+  intptr_t ap = (intptr_t)a;
+  void *b = cast_intptr_to_voidstar(ap);
+  intptr_t c = cast_voidstar_to_intptr(b);
+  void *d = cast_intptr_to_voidstar(c);
+
+  tt_assert(ap == c);
+  tt_assert(b == d);
+
+ done:
+  return;
+}
+
+/** Test for possibility of casting `int` to `void *` and back. */
+static void
+test_int_voidstar_interop(void *arg)
+{
+  int a;
+  (void)arg;
+
+  for (a = -1024; a <= 1024; a++) {
+    assert_int_voidptr_roundtrip(a);
+  }
+
+  for (a = INT_MIN; a <= INT_MIN+1024; a++) {
+    assert_int_voidptr_roundtrip(a);
+  }
+
+  for (a = INT_MAX-1024; a < INT_MAX; a++) {
+    assert_int_voidptr_roundtrip(a);
+  }
+
+  a = 1;
+  for (unsigned long i = 0; i < sizeof(int) * 8; i++) {
+    assert_int_voidptr_roundtrip(a);
+    a = (a << 1);
+  }
+}
+
+/** Assert that <b>a</b> can be cast to void * and back. */
+static void
+assert_uint_voidptr_roundtrip(unsigned int a)
+{
+ uintptr_t ap = (uintptr_t)a;
+ void *b = cast_uintptr_to_voidstar(ap);
+ uintptr_t c = cast_voidstar_to_uintptr(b);
+ void *d = cast_uintptr_to_voidstar(c);
+
+ tt_assert(ap == c);
+ tt_assert(b == d);
+
+ done:
+  return;
+}
+
+/** Test for possibility of casting `int` to `void *` and back. */
+static void
+test_uint_voidstar_interop(void *arg)
+{
+  unsigned int a;
+  (void)arg;
+
+  for (a = 0; a <= 1024; a++) {
+    assert_uint_voidptr_roundtrip(a);
+  }
+
+  for (a = UINT_MAX-1024; a < UINT_MAX; a++) {
+    assert_uint_voidptr_roundtrip(a);
+  }
+
+  a = 1;
+  for (unsigned long i = 0; i < sizeof(int) * 8; i++) {
+    assert_uint_voidptr_roundtrip(a);
+    a = (a << 1);
+  }
+}
+
+struct testcase_t slow_ptr_tests[] = {
+  { .name = "int_voidstar_interop",
+    .fn = test_int_voidstar_interop,
+    .flags = 0,
+    .setup = NULL,
+    .setup_data = NULL },
+  { .name = "uint_voidstar_interop",
+    .fn = test_uint_voidstar_interop,
+    .flags = 0,
+    .setup = NULL,
+    .setup_data = NULL },
+  END_OF_TESTCASES
+};

src/test/test_slow.c

@@ -22,6 +22,7 @@ struct testgroup_t testgroups[] = {
   { "slow/crypto/", slow_crypto_tests },
   { "slow/process/", slow_process_tests },
   { "slow/prob_distr/", slow_stochastic_prob_distr_tests },
+  { "slow/ptr/", slow_ptr_tests },
   END_OF_GROUPS
 };