From a7c7bea1c3ab4fdf985f5e520cec6d4f276a47d2 Mon Sep 17 00:00:00 2001
From: Daniel Bevenius <daniel.bevenius@gmail.com>
Date: Thu, 20 Apr 2017 20:08:53 +0200
Subject: [PATCH 1/3] src: add linux getauxval(AT_SECURE) in SafeGetenv

This commit attempts to fix the following TODO:
// TODO(bnoordhuis) Should perhaps also check whether
getauxval(AT_SECURE) is non-zero on Linux.

This can be manually tested at the moment using the following steps:

$ setcap cap_net_raw+ep out/Release/node
$ NODE_PENDING_DEPRECATION="1" out/Release/node -p
"process.binding('config').pendingDeprecation"
true
$ useradd test
$ su test
$ NODE_PENDING_DEPRECATION="1" out/Release/node -p
"process.binding('config').pendingDeprecation"
undefined
---
 src/node.cc      |  8 ++++++--
 src/node_main.cc | 26 ++++++++++++++++++++++++++
 2 files changed, 32 insertions(+), 2 deletions(-)

diff --git a/src/node.cc b/src/node.cc
index fb98fcebc2a4a5..db74414f10e98c 100644
--- a/src/node.cc
+++ b/src/node.cc
@@ -230,6 +230,8 @@ bool config_expose_internals = false;
 
 bool v8_initialized = false;
 
+bool linux_at_secure = false;
+
 // process-relative uptime base, initialized at start-up
 static double prog_start_time;
 static bool debugger_running;
@@ -959,13 +961,15 @@ Local<Value> UVException(Isolate* isolate,
 // Look up environment variable unless running as setuid root.
 bool SafeGetenv(const char* key, std::string* text) {
 #ifndef _WIN32
-  // TODO(bnoordhuis) Should perhaps also check whether getauxval(AT_SECURE)
-  // is non-zero on Linux.
   if (getuid() != geteuid() || getgid() != getegid()) {
     text->clear();
     return false;
   }
 #endif
+  if (linux_at_secure) {
+    text->clear();
+    return false;
+  }
   if (const char* value = getenv(key)) {
     *text = value;
     return true;
diff --git a/src/node_main.cc b/src/node_main.cc
index 3194eb78cab130..dcea04e6be953d 100644
--- a/src/node_main.cc
+++ b/src/node_main.cc
@@ -71,7 +71,33 @@ int wmain(int argc, wchar_t *wargv[]) {
 }
 #else
 // UNIX
+#ifdef __linux__
+#include <elf.h>
+#include <inttypes.h>
+#ifdef __LP64__
+#define Elf_auxv_t Elf64_auxv_t
+#else
+#define Elf_auxv_t Elf32_auxv_t
+#endif  // __LP64__
+extern char **environ;
+#endif  // __linux__
+
+namespace node {
+  extern bool linux_at_secure;
+}  // namespace node
+
 int main(int argc, char *argv[]) {
+#if defined(__linux__)
+  char** envp = environ;
+  while (*envp++ != nullptr) {}
+  Elf_auxv_t* auxv = reinterpret_cast<Elf_auxv_t*>(envp);
+  for (; auxv->a_type != AT_NULL; auxv++) {
+    if (auxv->a_type == AT_SECURE) {
+      node::linux_at_secure = auxv->a_un.a_val;
+      break;
+    }
+  }
+#endif
   // Disable stdio buffering, it interacts poorly with printf()
   // calls elsewhere in the program (e.g., any logging from V8.)
   setvbuf(stdout, nullptr, _IONBF, 0);

From 21f24463d19f2efca547b8dce4e5d16ab3ebcdb1 Mon Sep 17 00:00:00 2001
From: Daniel Bevenius <daniel.bevenius@gmail.com>
Date: Wed, 24 May 2017 19:59:31 +0200
Subject: [PATCH 2/3] remove unused inttypes.h

---
 src/node_main.cc | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/node_main.cc b/src/node_main.cc
index dcea04e6be953d..0b4a9da9f4dc2b 100644
--- a/src/node_main.cc
+++ b/src/node_main.cc
@@ -73,7 +73,6 @@ int wmain(int argc, wchar_t *wargv[]) {
 // UNIX
 #ifdef __linux__
 #include <elf.h>
-#include <inttypes.h>
 #ifdef __LP64__
 #define Elf_auxv_t Elf64_auxv_t
 #else

From e4eb85519c8caaabcf0ec373afb0d65f95c4accd Mon Sep 17 00:00:00 2001
From: Daniel Bevenius <daniel.bevenius@gmail.com>
Date: Wed, 24 May 2017 20:00:13 +0200
Subject: [PATCH 3/3] fix pointer style

---
 src/node_main.cc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/node_main.cc b/src/node_main.cc
index 0b4a9da9f4dc2b..7d6d9b1a01bbd4 100644
--- a/src/node_main.cc
+++ b/src/node_main.cc
@@ -78,7 +78,7 @@ int wmain(int argc, wchar_t *wargv[]) {
 #else
 #define Elf_auxv_t Elf32_auxv_t
 #endif  // __LP64__
-extern char **environ;
+extern char** environ;
 #endif  // __linux__
 
 namespace node {