Update NSPR to 4.12 and NSS to 3.23 on iOS

nspr/pr/src/misc/prenv.c

 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #include <string.h>
+#include <stdlib.h>
 #include "primpl.h"
 #include "prmem.h"
 
 #if defined(XP_UNIX)
+#include <unistd.h>
 #if defined(DARWIN)
 #if defined(HAVE_CRT_EXTERNS_H)
 #include <crt_externs.h>
 #endif /* HAVE_CRT_EXTERNS_H */
 #else  /* DARWIN */
 PR_IMPORT_DATA(char **) environ;
 #endif /* DARWIN */
 #endif /* XP_UNIX */
 
+#if !defined(HAVE_SECURE_GETENV) && defined(HAVE___SECURE_GETENV)
+#define secure_getenv __secure_getenv
+#define HAVE_SECURE_GETENV 1
+#endif
+
 /* Lock used to lock the environment */
 #if defined(_PR_NO_PREEMPT)
 #define _PR_NEW_LOCK_ENV()
 #define _PR_DELETE_LOCK_ENV()
 #define _PR_LOCK_ENV()
 #define _PR_UNLOCK_ENV()
 #elif defined(_PR_LOCAL_THREADS_ONLY)
 extern _PRCPU * _pr_primordialCPU;
 static PRIntn _is;
 #define _PR_NEW_LOCK_ENV()
@@ skipping 26 matching lines @@
     char *ev;
 
     if (!_pr_initialized) _PR_ImplicitInitialization();
 
     _PR_LOCK_ENV();
     ev = _PR_MD_GET_ENV(var);
     _PR_UNLOCK_ENV();
     return ev;
 }
 
+PR_IMPLEMENT(char*) PR_GetEnvSecure(const char *var)
+{
+#ifdef HAVE_SECURE_GETENV
+  char *ev;
+
+  if (!_pr_initialized) _PR_ImplicitInitialization();
+
+  _PR_LOCK_ENV();
+  ev = secure_getenv(var);
+  _PR_UNLOCK_ENV();
+
+  return ev;
+#else
+#ifdef XP_UNIX
+  /*
+  ** Fall back to checking uids and gids.  This won't detect any other
+  ** privilege-granting mechanisms the platform may have.  This also
+  ** can't detect the case where the process already called
+  ** setuid(geteuid()) and/or setgid(getegid()).
+  */
+  if (getuid() != geteuid() || getgid() != getegid()) {
+    return NULL;
+  }
+#endif /* XP_UNIX */
+  return PR_GetEnv(var);
+#endif /* HAVE_SECURE_GETENV */
+}
+
 PR_IMPLEMENT(PRStatus) PR_SetEnv(const char *string)
 {
     PRIntn result;
 
     if (!_pr_initialized) _PR_ImplicitInitialization();
 
     if (!strchr(string, '=')) return(PR_FAILURE);
 
     _PR_LOCK_ENV();
     result = _PR_MD_PUT_ENV((char*)string);
@@ skipping 42 matching lines @@
     _PR_UNLOCK_ENV();
     return result;
 }
 #else
 /* This platform doesn't support raw access to the environ block. */
 PR_IMPLEMENT(char **) PR_DuplicateEnvironment(void)
 {
     return NULL;
 }
 #endif