diff options
Diffstat (limited to 'lib/secure_getenv.c')
| -rw-r--r-- | lib/secure_getenv.c | 31 |
1 files changed, 22 insertions, 9 deletions
diff --git a/lib/secure_getenv.c b/lib/secure_getenv.c index 7b86173bb..821cb092d 100644 --- a/lib/secure_getenv.c +++ b/lib/secure_getenv.c @@ -1,6 +1,6 @@ -/* Look up an environment variable more securely. +/* Look up an environment variable, returning NULL in insecure situations. - Copyright 2013-2014 Free Software Foundation, Inc. + Copyright 2013-2016 Free Software Foundation, Inc. This program is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published @@ -20,22 +20,35 @@ #include <stdlib.h> #if !HAVE___SECURE_GETENV -# if HAVE_ISSETUGID +# if HAVE_ISSETUGID || (HAVE_GETUID && HAVE_GETEUID && HAVE_GETGID && HAVE_GETEGID) # include <unistd.h> -# else -# undef issetugid -# define issetugid() 1 # endif #endif char * secure_getenv (char const *name) { -#if HAVE___SECURE_GETENV +#if HAVE___SECURE_GETENV /* glibc */ return __secure_getenv (name); -#else +#elif HAVE_ISSETUGID /* OS X, FreeBSD, NetBSD, OpenBSD */ if (issetugid ()) - return 0; + return NULL; + return getenv (name); +#elif HAVE_GETUID && HAVE_GETEUID && HAVE_GETGID && HAVE_GETEGID /* other Unix */ + if (geteuid () != getuid () || getegid () != getgid ()) + return NULL; return getenv (name); +#elif (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__ /* native Windows */ + /* On native Windows, there is no such concept as setuid or setgid binaries. + - Programs launched as system services have high privileges, but they don't + inherit environment variables from a user. + - Programs launched by a user with "Run as Administrator" have high + privileges and use the environment variables, but the user has been asked + whether he agrees. + - Programs launched by a user without "Run as Administrator" cannot gain + high privileges, therefore there is no risk. */ + return getenv (name); +#else + return NULL; #endif } |