/*
* OpenVPN -- An application to securely tunnel IP networks
* over a single TCP/UDP port, with support for SSL/TLS-based
* session authentication and key exchange,
* packet encryption, packet authentication, and
* packet compression.
*
* Copyright (C) 2002-2010 OpenVPN Technologies, Inc. <sales@openvpn.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program (see the file COPYING included with this
* distribution); if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef MISC_H
#define MISC_H
#include "basic.h"
#include "common.h"
#include "integer.h"
#include "buffer.h"
/* socket descriptor passed by inetd/xinetd server to us */
#define INETD_SOCKET_DESCRIPTOR 0
/* forward declarations */
struct plugin_list;
/* used by argv_x functions */
struct argv {
size_t capacity;
size_t argc;
char **argv;
char *system_str;
};
/*
* Handle environmental variable lists
*/
struct env_item {
char *string;
struct env_item *next;
};
struct env_set {
struct gc_arena *gc;
struct env_item *list;
};
/* Get/Set UID of process */
struct user_state {
#if defined(HAVE_GETPWNAM) && defined(HAVE_SETUID)
const char *username;
struct passwd *pw;
#else
int dummy;
#endif
};
bool get_user (const char *username, struct user_state *state);
void set_user (const struct user_state *state);
/* Get/Set GID of process */
struct group_state {
#if defined(HAVE_GETGRNAM) && defined(HAVE_SETGID)
const char *groupname;
struct group *gr;
#else
int dummy;
#endif
};
bool get_group (const char *groupname, struct group_state *state);
void set_group (const struct group_state *state);
void set_nice (int niceval);
void do_chroot (const char *path);
void run_up_down (const char *command,
const struct plugin_list *plugins,
int plugin_type,
const char *arg,
int tun_mtu,
int link_mtu,
const char *ifconfig_local,
const char* ifconfig_remote,
const char *context,
const char *signal_text,
const char *script_type,
struct env_set *es);
/* workspace for get_pid_file/write_pid */
struct pid_state {
FILE *fp;
const char *filename;
};
void get_pid_file (const char* filename, struct pid_state *state);
void write_pid (const struct pid_state *state);
unsigned int openvpn_getpid (void);
void do_mlockall (bool print_msg); /* Disable paging */
#ifndef HAVE_DAEMON
int daemon (int nochdir, int noclose);
#endif
/* check file protections */
void warn_if_group_others_accessible(const char* filename);
/* system flags */
#define S_SCRIPT (1<<0)
#define S_FATAL (1<<1)
/* interpret the status code returned by system()/execve() */
bool system_ok(int);
bool system_executed (int stat);
const char *system_error_message (int, struct gc_arena *gc);
/* wrapper around the execve() call */
int openvpn_execve (const struct argv *a, const struct env_set *es, const unsigned int flags);
bool openvpn_execve_check (const struct argv *a, const struct env_set *es, const unsigned int flags, const char *error_message);
bool openvpn_execve_allowed (const unsigned int flags);
int openvpn_system (const char *command, const struct env_set *es, unsigned int flags);
static inline bool
openvpn_run_script (const struct argv *a, const struct env_set *es, const unsigned int flags, const char *hook)
{
char msg[256];
openvpn_snprintf(msg, sizeof(msg), "WARNING: Failed running command (%s)", hook);
return openvpn_execve_check(a, es, flags | S_SCRIPT, msg);
};
#ifdef HAVE_STRERROR
/* a thread-safe version of strerror */
const char* strerror_ts (int errnum, struct gc_arena *gc);
#endif
/* Set standard file descriptors to /dev/null */
void set_std_files_to_null (bool stdin_only);
/* Wrapper for chdir library function */
int openvpn_chdir (const char* dir);
/* dup inetd/xinetd socket descriptor and save */
extern int inetd_socket_descriptor;
void save_inetd_socket_descriptor (void);
/* init random() function, only used as source for weak random numbers, when !USE_CRYPTO */
void init_random_seed(void);
/* set/delete environmental variable */
void setenv_str_ex (struct env_set *es,
const char *name,
const char *value,
const unsigned int name_include,
const unsigned int name_exclude,
const char name_replace,
const unsigned int value_include,
const unsigned int value_exclude,
const char value_replace);
void setenv_counter (struct env_set *es, const char *name, counter_type value);
void setenv_int (struct env_set *es, const char *name, int value);
void setenv_unsigned (struct env_set *es, const char *name, unsigned int value);
void setenv_str (struct env_set *es, const char *name, const char *value);
void setenv_str_safe (struct env_set *es, const char *name, const char *value);
void setenv_del (struct env_set *es, const char *name);
void setenv_int_i (struct env_set *es, const char *name, const int value, const int i);
void setenv_str_i (struct env_set *es, const char *name, const char *value, const int i);
/* struct env_set functions */
struct env_set *env_set_create (struct gc_arena *gc);
void env_set_destroy (struct env_set *es);
bool env_set_del (struct env_set *es, const char *str);
void env_set_add (struct env_set *es, const char *str);
void env_set_print (int msglevel, const struct env_set *es);
void env_set_inherit (struct env_set *es, const struct env_set *src);
void env_set_add_to_environment (const struct env_set *es);
void env_set_remove_from_environment (const struct env_set *es);
/* Make arrays of strings */
const char **make_env_array (const struct env_set *es,
const bool check_allowed,
struct gc_arena *gc);
const char **make_arg_array (const char *first, const char *parms, struct gc_arena *gc);
const char **make_extended_arg_array (char **p, struct gc_arena *gc);
/* convert netmasks for iproute2 */
int count_netmask_bits(const char *);
unsigned int count_bits(unsigned int );
/* go to sleep for n milliseconds */
void sleep_milliseconds (unsigned int n);
/* go to sleep indefinitely */
void sleep_until_signal (void);
/* an analogue to the random() function, but use OpenSSL functions if available */
#ifdef USE_CRYPTO
long int get_random(void);
#else
#define get_random random
#endif
/* return true if filename can be opened for read */
bool test_file (const char *filename);
/* create a temporary file in directory, returns the filename of the created file */
const char *create_temp_file (const char *directory, const char *prefix, struct gc_arena *gc);
/* put a directory and filename together */
const char *gen_path (const char *directory, const char *filename, struct gc_arena *gc);
/* delete a file, return true if succeeded */
bool delete_file (const char *filename);
/* return true if pathname is absolute */
bool absolute_pathname (const char *pathname);
/* prepend a random prefix to hostname (need USE_CRYPTO) */
const char *hostname_randomize(const char *hostname, struct gc_arena *gc);
/*
* Get and store a username/password
*/
struct user_pass
{
bool defined;
bool nocache;
/* max length of username/password */
# ifdef ENABLE_PKCS11
# define USER_PASS_LEN 4096
# else
# define USER_PASS_LEN 128
# endif
char username[USER_PASS_LEN];
char password[USER_PASS_LEN];
};
bool get_console_input (const char *prompt, const bool echo, char *input, const int capacity);
/*
* Flags for get_user_pass and management_query_user_pass
*/
#define GET_USER_PASS_MANAGEMENT (1<<0)
#define GET_USER_PASS_SENSITIVE (1<<1)
#define GET_USER_PASS_PASSWORD_ONLY (1<<2)
#define GET_USER_PASS_NEED_OK (1<<3)
#define GET_USER_PASS_NOFATAL (1<<4)
#define GET_USER_PASS_NEED_STR (1<<5)
#define GET_USER_PASS_PREVIOUS_CREDS_FAILED (1<<6)
bool get_user_pass (struct user_pass *up,
const char *auth_file,
const char *prefix,
const unsigned int flags);
void fail_user_pass (const char *prefix,
const unsigned int flags,
const char *reason);
void purge_user_pass (struct user_pass *up, const bool force);
/*
* Process string received by untrusted peer before
* printing to console or log file.
* Assumes that string has been null terminated.
*/
const char *safe_print (const char *str, struct gc_arena *gc);
/* returns true if environmental variable safe to print to log */
bool env_safe_to_print (const char *str);
/* returns true if environmental variable may be passed to an external program */
bool env_allowed (const char *str);
/*
* A sleep function that services the management layer for n
* seconds rather than doing nothing.
*/
void openvpn_sleep (const int n);
void configure_path (void);
#if AUTO_USERID
void get_user_pass_auto_userid (struct user_pass *up, const char *tag);
#endif
/*
* /sbin/ip path, may be overridden
*/
#ifdef CONFIG_FEATURE_IPROUTE
extern const char *iproute_path;
#endif
/* Script security */
#define SSEC_NONE 0 /* strictly no calling of external programs */
#define SSEC_BUILT_IN 1 /* only call built-in programs such as ifconfig, route, netsh, etc.*/
#define SSEC_SCRIPTS 2 /* allow calling of built-in programs and user-defined scripts */
#define SSEC_PW_ENV 3 /* allow calling of built-in programs and user-defined scripts that may receive a password as an environmental variable */
extern int script_security; /* GLOBAL */
#define SM_EXECVE 0 /* call external programs with execve() or CreateProcess() */
#define SM_SYSTEM 1 /* call external programs with system() */
extern int script_method; /* GLOBAL */
/* return the next largest power of 2 */
size_t adjust_power_of_2 (size_t u);
/* return the basename of path */
const char *openvpn_basename (const char *path);
/*
* A printf-like function (that only recognizes a subset of standard printf
* format operators) that prints arguments to an argv list instead
* of a standard string. This is used to build up argv arrays for passing
* to execve.
*/
void argv_init (struct argv *a);
struct argv argv_new (void);
void argv_reset (struct argv *a);
char *argv_term (const char **f);
const char *argv_str (const struct argv *a, struct gc_arena *gc, const unsigned int flags);
struct argv argv_insert_head (const struct argv *a, const char *head);
void argv_msg (const int msglev, const struct argv *a);
void argv_msg_prefix (const int msglev, const struct argv *a, const char *prefix);
const char *argv_system_str (const struct argv *a);
#define APA_CAT (1<<0) /* concatentate onto existing struct argv list */
void argv_printf_arglist (struct argv *a, const char *format, const unsigned int flags, va_list arglist);
void argv_printf (struct argv *a, const char *format, ...)
#ifdef __GNUC__
__attribute__ ((format (printf, 2, 3)))
#endif
;
void argv_printf_cat (struct argv *a, const char *format, ...)
#ifdef __GNUC__
__attribute__ ((format (printf, 2, 3)))
#endif
;
/*
* Extract UID or GID
*/
static inline int
user_state_uid (const struct user_state *s)
{
#if defined(HAVE_GETPWNAM) && defined(HAVE_SETUID)
if (s->pw)
return s->pw->pw_uid;
#endif
return -1;
}
static inline int
group_state_gid (const struct group_state *s)
{
#if defined(HAVE_GETGRNAM) && defined(HAVE_SETGID)
if (s->gr)
return s->gr->gr_gid;
#endif
return -1;
}
#endif
