util.pposix: Replace the unwieldy module table generation with luaL_register() call...
[prosody.git] / util-src / pposix.c
index 5e15ed7625a107789412e848540b01bfebe19198..49521a163e73dddac2521c173f40122896bb3fd9 100644 (file)
@@ -1,47 +1,52 @@
-/* Prosody IM v0.1
--- Copyright (C) 2008 Matthew Wild
--- Copyright (C) 2008 Waqas Hussain
--- 
--- This program is free software; you can redistribute it and/or
--- modify it under the terms of the GNU General Public License
--- as published by the Free Software Foundation; either version 2
--- of the License, or (at your option) any later version.
--- 
--- 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; if not, write to the Free Software
--- Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+/* Prosody IM v0.4
+-- Copyright (C) 2008-2009 Matthew Wild
+-- Copyright (C) 2008-2009 Waqas Hussain
+-- Copyright (C) 2009 Tobias Markmann
+--
+-- This project is MIT/X11 licensed. Please see the
+-- COPYING file in the source package for more information.
+--
 */
 
-/* pposix.c
-   POSIX support functions for Lua
+/*
+* pposix.c
+* POSIX support functions for Lua
 */
 
+#define MODULE_VERSION "0.3.2"
+
 #include <stdlib.h>
+#include <math.h>
 #include <unistd.h>
 #include <libgen.h>
+#include <sys/resource.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
 
+#include <syslog.h>
+#include <pwd.h>
+#include <grp.h>
+
+#include <string.h>
+#include <errno.h>
 #include "lua.h"
+#include "lauxlib.h"
 
-static int daemonize(lua_State *L)
+/* Daemonization support */
+
+static int lc_daemonize(lua_State *L)
 {
 
        pid_t pid;
-       
+
        if ( getppid() == 1 )
        {
                lua_pushboolean(L, 0);
                lua_pushstring(L, "already-daemonized");
                return 2;
        }
-       
+
        /* Attempt initial fork */
        if((pid = fork()) < 0)
        {
@@ -57,7 +62,7 @@ static int daemonize(lua_State *L)
                lua_pushnumber(L, pid);
                return 2;
        }
-       
+
        /* and we are the child process */
        if(setsid() == -1)
        {
@@ -69,10 +74,10 @@ static int daemonize(lua_State *L)
        }
 
        /* Close stdin, stdout, stderr */
-/*     close(0);
+       close(0);
        close(1);
        close(2);
-*/
+
        /* Final fork, use it wisely */
        if(fork())
                exit(0);
@@ -83,10 +88,436 @@ static int daemonize(lua_State *L)
        return 2;
 }
 
+/* Syslog support */
+
+const char * const facility_strings[] = {
+                                       "auth",
+#if !(defined(sun) || defined(__sun))
+                                       "authpriv",
+#endif
+                                       "cron",
+                                       "daemon",
+#if !(defined(sun) || defined(__sun))
+                                       "ftp",
+#endif
+                                       "kern",
+                                       "local0",
+                                       "local1",
+                                       "local2",
+                                       "local3",
+                                       "local4",
+                                       "local5",
+                                       "local6",
+                                       "local7",
+                                       "lpr",
+                                       "mail",
+                                       "syslog",
+                                       "user",
+                                       "uucp",
+                                       NULL
+                               };
+int facility_constants[] =     {
+                                       LOG_AUTH,
+#if !(defined(sun) || defined(__sun))
+                                       LOG_AUTHPRIV,
+#endif
+                                       LOG_CRON,
+                                       LOG_DAEMON,
+#if !(defined(sun) || defined(__sun))
+                                       LOG_FTP,
+#endif
+                                       LOG_KERN,
+                                       LOG_LOCAL0,
+                                       LOG_LOCAL1,
+                                       LOG_LOCAL2,
+                                       LOG_LOCAL3,
+                                       LOG_LOCAL4,
+                                       LOG_LOCAL5,
+                                       LOG_LOCAL6,
+                                       LOG_LOCAL7,
+                                       LOG_LPR,
+                                       LOG_MAIL,
+                                       LOG_NEWS,
+                                       LOG_SYSLOG,
+                                       LOG_USER,
+                                       LOG_UUCP,
+                                       -1
+                               };
+
+/* "
+       The parameter ident in the call of openlog() is probably stored  as-is.
+       Thus,  if  the  string  it  points  to  is  changed, syslog() may start
+       prepending the changed string, and if the string it points to ceases to
+       exist,  the  results  are  undefined.  Most portable is to use a string
+       constant.
+   " -- syslog manpage
+*/
+char* syslog_ident = NULL;
+
+int lc_syslog_open(lua_State* L)
+{
+       int facility = luaL_checkoption(L, 2, "daemon", facility_strings);
+       facility = facility_constants[facility];
+
+       luaL_checkstring(L, 1);
+
+       if(syslog_ident)
+               free(syslog_ident);
+
+       syslog_ident = strdup(lua_tostring(L, 1));
+
+       openlog(syslog_ident, LOG_PID, facility);
+       return 0;
+}
+
+const char * const level_strings[] = {
+                               "debug",
+                               "info",
+                               "notice",
+                               "warn",
+                               "error",
+                               NULL
+                       };
+int level_constants[] =        {
+                               LOG_DEBUG,
+                               LOG_INFO,
+                               LOG_NOTICE,
+                               LOG_WARNING,
+                               LOG_CRIT,
+                               -1
+                       };
+int lc_syslog_log(lua_State* L)
+{
+       int level = luaL_checkoption(L, 1, "notice", level_strings);
+       level = level_constants[level];
+
+       luaL_checkstring(L, 2);
+
+       syslog(level, "%s", lua_tostring(L, 2));
+       return 0;
+}
+
+int lc_syslog_close(lua_State* L)
+{
+       closelog();
+       if(syslog_ident)
+       {
+               free(syslog_ident);
+               syslog_ident = NULL;
+       }
+       return 0;
+}
+
+int lc_syslog_setmask(lua_State* L)
+{
+       int level_idx = luaL_checkoption(L, 1, "notice", level_strings);
+       int mask = 0;
+       do
+       {
+               mask |= LOG_MASK(level_constants[level_idx]);
+       } while (++level_idx<=4);
+
+       setlogmask(mask);
+       return 0;
+}
+
+/* getpid */
+
+int lc_getpid(lua_State* L)
+{
+       lua_pushinteger(L, getpid());
+       return 1;
+}
+
+/* UID/GID functions */
+
+int lc_getuid(lua_State* L)
+{
+       lua_pushinteger(L, getuid());
+       return 1;
+}
+
+int lc_getgid(lua_State* L)
+{
+       lua_pushinteger(L, getgid());
+       return 1;
+}
+
+int lc_setuid(lua_State* L)
+{
+       int uid = -1;
+       if(lua_gettop(L) < 1)
+               return 0;
+       if(!lua_isnumber(L, 1) && lua_tostring(L, 1))
+       {
+               /* Passed UID is actually a string, so look up the UID */
+               struct passwd *p;
+               p = getpwnam(lua_tostring(L, 1));
+               if(!p)
+               {
+                       lua_pushboolean(L, 0);
+                       lua_pushstring(L, "no-such-user");
+                       return 2;
+               }
+               uid = p->pw_uid;
+       }
+       else
+       {
+               uid = lua_tonumber(L, 1);
+       }
+
+       if(uid>-1)
+       {
+               /* Ok, attempt setuid */
+               errno = 0;
+               if(setuid(uid))
+               {
+                       /* Fail */
+                       lua_pushboolean(L, 0);
+                       switch(errno)
+                       {
+                       case EINVAL:
+                               lua_pushstring(L, "invalid-uid");
+                               break;
+                       case EPERM:
+                               lua_pushstring(L, "permission-denied");
+                               break;
+                       default:
+                               lua_pushstring(L, "unknown-error");
+                       }
+                       return 2;
+               }
+               else
+               {
+                       /* Success! */
+                       lua_pushboolean(L, 1);
+                       return 1;
+               }
+       }
+
+       /* Seems we couldn't find a valid UID to switch to */
+       lua_pushboolean(L, 0);
+       lua_pushstring(L, "invalid-uid");
+       return 2;
+}
+
+int lc_setgid(lua_State* L)
+{
+       int gid = -1;
+       if(lua_gettop(L) < 1)
+               return 0;
+       if(!lua_isnumber(L, 1) && lua_tostring(L, 1))
+       {
+               /* Passed GID is actually a string, so look up the GID */
+               struct group *g;
+               g = getgrnam(lua_tostring(L, 1));
+               if(!g)
+               {
+                       lua_pushboolean(L, 0);
+                       lua_pushstring(L, "no-such-group");
+                       return 2;
+               }
+               gid = g->gr_gid;
+       }
+       else
+       {
+               gid = lua_tonumber(L, 1);
+       }
+
+       if(gid>-1)
+       {
+               /* Ok, attempt setgid */
+               errno = 0;
+               if(setgid(gid))
+               {
+                       /* Fail */
+                       lua_pushboolean(L, 0);
+                       switch(errno)
+                       {
+                       case EINVAL:
+                               lua_pushstring(L, "invalid-gid");
+                               break;
+                       case EPERM:
+                               lua_pushstring(L, "permission-denied");
+                               break;
+                       default:
+                               lua_pushstring(L, "unknown-error");
+                       }
+                       return 2;
+               }
+               else
+               {
+                       /* Success! */
+                       lua_pushboolean(L, 1);
+                       return 1;
+               }
+       }
+
+       /* Seems we couldn't find a valid GID to switch to */
+       lua_pushboolean(L, 0);
+       lua_pushstring(L, "invalid-gid");
+       return 2;
+}
+
+int lc_umask(lua_State* L)
+{
+       char old_mode_string[7];
+       mode_t old_mode = umask(strtoul(luaL_checkstring(L, 1), NULL, 8));
+
+       snprintf(old_mode_string, sizeof(old_mode_string), "%03o", old_mode);
+       old_mode_string[sizeof(old_mode_string)-1] = 0;
+       lua_pushstring(L, old_mode_string);
+
+       return 1;
+}
+
+/*     Like POSIX's setrlimit()/getrlimit() API functions.
+ *
+ *     Syntax:
+ *     pposix.setrlimit( resource, soft limit, hard limit)
+ *
+ *     Any negative limit will be replace with the current limit by an additional call of getrlimit().
+ *
+ *     Example usage:
+ *     pposix.setrlimit("NOFILE", 1000, 2000)
+ */
+int string2resource(const char *s) {
+       if (!strcmp(s, "CORE")) return RLIMIT_CORE;
+       if (!strcmp(s, "CPU")) return RLIMIT_CPU;
+       if (!strcmp(s, "DATA")) return RLIMIT_DATA;
+       if (!strcmp(s, "FSIZE")) return RLIMIT_FSIZE;
+       if (!strcmp(s, "NOFILE")) return RLIMIT_NOFILE;
+       if (!strcmp(s, "STACK")) return RLIMIT_STACK;
+#if !(defined(sun) || defined(__sun))
+       if (!strcmp(s, "MEMLOCK")) return RLIMIT_MEMLOCK;
+       if (!strcmp(s, "NPROC")) return RLIMIT_NPROC;
+       if (!strcmp(s, "RSS")) return RLIMIT_RSS;
+#endif
+       return -1;
+}
+
+int lc_setrlimit(lua_State *L) {
+       int arguments = lua_gettop(L);
+       int softlimit = -1;
+       int hardlimit = -1;
+       const char *resource = NULL;
+       int rid = -1;
+       if(arguments < 1 || arguments > 3) {
+               lua_pushboolean(L, 0);
+               lua_pushstring(L, "incorrect-arguments");
+       }
+
+       resource = luaL_checkstring(L, 1);
+       softlimit = luaL_checkinteger(L, 2);
+       hardlimit = luaL_checkinteger(L, 3);
+
+       rid = string2resource(resource);
+       if (rid != -1) {
+               struct rlimit lim;
+               struct rlimit lim_current;
+
+               if (softlimit < 0 || hardlimit < 0) {
+                       if (getrlimit(rid, &lim_current)) {
+                               lua_pushboolean(L, 0);
+                               lua_pushstring(L, "getrlimit-failed");
+                               return 2;
+                       }
+               }
+
+               if (softlimit < 0) lim.rlim_cur = lim_current.rlim_cur;
+                       else lim.rlim_cur = softlimit;
+               if (hardlimit < 0) lim.rlim_max = lim_current.rlim_max;
+                       else lim.rlim_max = hardlimit;
+
+               if (setrlimit(rid, &lim)) {
+                       lua_pushboolean(L, 0);
+                       lua_pushstring(L, "setrlimit-failed");
+                       return 2;
+               }
+       } else {
+               /* Unsupported resoucrce. Sorry I'm pretty limited by POSIX standard. */
+               lua_pushboolean(L, 0);
+               lua_pushstring(L, "invalid-resource");
+               return 2;
+       }
+       lua_pushboolean(L, 1);
+       return 1;
+}
+
+int lc_getrlimit(lua_State *L) {
+       int arguments = lua_gettop(L);
+       const char *resource = NULL;
+       int rid = -1;
+       struct rlimit lim;
+
+       if (arguments != 1) {
+               lua_pushboolean(L, 0);
+               lua_pushstring(L, "invalid-arguments");
+               return 2;
+       }
+
+       resource = luaL_checkstring(L, 1);
+       rid = string2resource(resource);
+       if (rid != -1) {
+               if (getrlimit(rid, &lim)) {
+                       lua_pushboolean(L, 0);
+                       lua_pushstring(L, "getrlimit-failed.");
+                       return 2;
+               }
+       } else {
+               /* Unsupported resoucrce. Sorry I'm pretty limited by POSIX standard. */
+               lua_pushboolean(L, 0);
+               lua_pushstring(L, "invalid-resource");
+               return 2;
+       }
+       lua_pushboolean(L, 1);
+       lua_pushnumber(L, lim.rlim_cur);
+       lua_pushnumber(L, lim.rlim_max);
+       return 3;
+}
+
+int lc_abort(lua_State* L)
+{
+       abort();
+       return 0;
+}
+
+/* Register functions */
+
 int luaopen_util_pposix(lua_State *L)
 {
-       lua_newtable(L);
-       lua_pushcfunction(L, daemonize);
-       lua_setfield(L, -2, "daemonize");
+       luaL_Reg exports[] = {
+               { "abort", lc_abort },
+
+               { "daemonize", lc_daemonize },
+
+               { "syslog_open", lc_syslog_open },
+               { "syslog_close", lc_syslog_close },
+               { "syslog_log", lc_syslog_log },
+               { "syslog_setminlevel", lc_syslog_setmask },
+
+               { "getpid", lc_getpid },
+               { "getuid", lc_getuid },
+               { "getgid", lc_getgid },
+
+               { "setuid", lc_setuid },
+               { "setgid", lc_setgid },
+
+               { "umask", lc_umask },
+
+               { "setrlimit", lc_setrlimit },
+               { "getrlimit", lc_getrlimit },
+
+               { NULL, NULL }
+       };
+
+       luaL_register(L, "pposix",  exports);
+
+       lua_pushliteral(L, "pposix");
+       lua_setfield(L, -2, "_NAME");
+
+       lua_pushliteral(L, MODULE_VERSION);
+       lua_setfield(L, -2, "_VERSION");
+
        return 1;
 };