/*========================================================== * Program : sms_serv.c                    Project : smslink * Authors : Philippe Andersson. *           Philipp Klaus <pklaus@access.ch>. * Date    : 25/02/00 * Version : 0.44b * Notice  : (c) Les Ateliers du Heron, 1998 for Scitex Europe, S.A. *           contributions (c) Internet Access AG, 1999. * Comment : SMS Server for Linux. Main source file (daemon core). * * Modification History : * - 0.01a (12/08/98) : Initial release. * - 0.02a (13/08/98) : Simmultaneous clients handling (fork). * - 0.03a (25/08/98) : Daemonized it. Started to implement *   use of syslog facility. Added handling function for SIGTERM. * - 0.10a (27/28/98) : Merge sms_serv with the parser module. * - 0.11a (01/09/98) : Completed output migration to socket *   (printf's to sprintf's). * - 0.12a (01/09/98) : Start implementing restricted access *   to non-sharable resources (modems) through semaphores. * - 0.13a (03/09/98) : Completed implementation of crit. *   sections through semaphores and shared memory. * - 0.14a (24/09/98) : Improved error handling when forking. * - 0.15a (27/09/98) : Display local hostname on server announce. * - 0.16a (30/09/98) : Reordered two lines - cosmetics. * - 0.17a (19/10/98) : Changed 'struct modem_def' to 'struct *   gsms_def' ; changed 'modemsdef' to 'gsmdevices'. Added *   GSM devices array init. from config file (GSMDEVFILE) for *   improved flexibility. Cosmetics. * - 0.20a (20/10/98) : Merge test program into main source *   tree. Implements the actual SMS sending. * ++++ Switch to Beta ++++ * - 0.21b (21/10/98) : First beta release. * - 0.22b (23/10/98) : Added 'user' member in struct 'symbols'. * - 0.30b (22/11/98) : Start implementing logic to regularly *   check on incoming messages. * - 0.31b (13/12/98) : Moved to sigaction() signal handling. *   Adapted gsmdevices initialization for new "owner" member. * - 0.32b (14/12/98) : Inserted a 1 sec. sleep time in the *   main loop. Prevents sms_serv eating up all the CPU cycles. *   The side effect is a slight delay when connecting - ok. * - 0.33b (06/02/99) : Included an access-list mechanism *   based on the client's IP address. Contributed by Philipp *   Klaus <pklaus@access.ch>. * - 0.34b (14/02/99) : Implemented a more flexible version *   of the ACL handling. * - 0.40b (16/05/99) : Added "starttime" variable for uptime *   computation. * - 0.41b (20/07/99) : Finalized incoming messages processing. *   No change to this file. * - 0.42b (18/08/99) : Added handling for a checkpoint file *   (for interaction with a SMS to Mail gateway module). Also *   modified a bit the order of appearance for unistd.h. Removed *   the HPUX-specific code. * - 0.43b (08/09/99) : Included version info in the server's *   initial syslog message. * - 0.44b (25/02/00) : Improved handling of the ckeckpoint file *   by mbchecker.c. No change in this file. *========================================================*/#include <unistd.h>                      /* for getopt () */#include <sys/types.h>#include <sys/socket.h>#include <sys/sem.h>           /* for semaphore functions */#include <sys/shm.h>       /* for shared memory functions */#include <sys/ipc.h>#include <netinet/in.h>     /* for AF_INET domain sockets */#include <arpa/inet.h>                /* for inet_addr () */#include <netdb.h>                /* for gethostbyname () */#include <fcntl.h>                        /* for fcntl () */#include <time.h>                      /* for difftime () */#include <syslog.h>#include <signal.h>#include <stdio.h>#include <stdlib.h>#include <errno.h>#include <string.h>               /* for strcpy & friends *//*--------------------------------------Personal includes */#include "sms_serv.h"/*========================================================*//**********             LOCAL DEFINES              ********//*========================================================*//* For debugging purposes only - comment out for normal compile *//* #define INCL_DEBUG_CODE *//*========================================================*//**********           GLOBAL VARIABLES             ********//*========================================================*/int csfd;                             /* client socket FD */char *buffer;                    /* read and write buffer */struct symbols symbols;              /* msg-specific data */int global_sem;       /* sem. for global send crit. sect. */int shmem_sem;             /* sem. for shared mem. access */int shmem_id;                   /* shared mem. identifier */void *shared_memory = (void *)0;     /* shared mem. addr. */time_t starttime;               /* for uptime calculation */struct gsms_def *gsmdevices;acl_list gsm_acl;int ngsmdevs = 0;                /* # defined GSM devices *//* for flex input */char myinput[];char *myinputptr;              /* current pos. in myinput */char *myinputlim;                   /* ptr to end of data *//*========================================================*//**********               FUNCTIONS                ********//*========================================================*//*========================================================*//**********           MAIN PROGRAM LOOP            ********//*========================================================*/main (){  struct servent *sent;  struct sockaddr_in s_addr;     /* server socket address */  struct sockaddr_in c_addr;     /* client socket address */  int ssfd;                           /* server socket FD */  int sockflags;                /* socket attribute flags */  time_t lastchked;  int c_addr_len;  /* size of struct returned by accept() */  int nread;  char *destgsm;  char *message;  char *localhost;  int pid, ppid, gppid;             /* for fork() testing */  int i;  int optval;                     /* INA setsockopt value */  struct gsms_def *gsmitem;  struct sigaction sa_f;    /*-------------------------First, let's become a daemon */  gppid = fork ();  if (gppid == -1)    syserr ("sms_serv: grand-father can't fork");  else if (gppid != 0)         exit (0);                /* grand-father's death */    /* open connection with the syslog daemon - announce */  openlog ("sms_serv", (LOG_CONS | LOG_PID), FACILITY);  syslog ((FACILITY | LOG_INFO), "server starting (v. %s)...", SMS_SERV_VERSION);    /* let's become group leader (thereby loosing my tty) */  if (setpgrp () == -1)    syserr ("sms_serv: can't become group leader");    /*--------------------------------------Initialisations */  /* Signal Handling - ignore some */  sa_f.sa_handler = SIG_IGN;  if (sigemptyset (&sa_f.sa_mask) == -1)    syserr ("sms_serv: can't empty signal set");  sa_f.sa_flags = 0;  if (sigaction (SIGHUP, &sa_f, NULL) == -1)    /* hangup */    syserr ("sms_serv: can't ignore SIGHUP");  if (sigaction (SIGCHLD, &sa_f, NULL) == -1)     syserr ("sms_serv: can't ignore SIGCHLD");  /* now do something meaningfull on SIGTERM */  sa_f.sa_handler = daemons_death;  if (sigfillset (&sa_f.sa_mask) == -1)    syserr ("sms_serv: can't fill signal set");  sa_f.sa_flags = 0;  if (sigaction (SIGTERM, &sa_f, NULL) == -1)    syserr ("sms_serv: can't catch SIGTERM");      /* first fork */  ppid = fork ();  if (ppid == -1)    syserr ("sms_serv: father can't fork");  else if (ppid != 0)         exit (0);                      /* father's death */  /*-------------------------------Start of daemon itself */  /* set the file creation mask */  /* umask (0); */  /* change directory to ...? */#ifndef INCL_DEBUG_CODE       /* we want to keep stdout for printf's */  /* close unused file descriptors */#endif  /* how many GSM devices do we have ? */  syslog ((FACILITY | LOG_INFO), "loading GSM module definitions...");  if ((ngsmdevs = getgsmdevscount (TRUE)) == 0) {    syslog ((FACILITY | LOG_INFO), "no GSM module definition found, exiting.");    syserr ("sms_serv: no defined GSM device");  }#ifdef INCL_DEBUG_CODE  fprintf (stderr, "getgsmdevscount() reported %d valid configs\n", ngsmdevs);#endif  if (ngsmdevs > MAXMODEMS) {    syslog ((FACILITY | LOG_INFO), "too many GSM module definitions found, exiting.");    syserr ("sms_serv: hardware can't support that many serial devices");  }      /* create and initialize semaphores */  if ((global_sem = semget (IPC_PRIVATE, 1, (0660 | IPC_CREAT | IPC_EXCL))) == -1)    syserr ("sms_serv: can't create global semaphore");  if (set_semvalue (global_sem, ngsmdevs) == -1)    syserr ("sms_serv: unable to initialize global semaphore");      if ((shmem_sem = semget (IPC_PRIVATE, 1, (0660 | IPC_CREAT | IPC_EXCL))) == -1)    syserr ("sms_serv: can't create shmem semaphore");  if (set_semvalue (shmem_sem, 1) == -1)    syserr ("sms_serv: unable to initialize shmem semaphore");    /* create shared memory segment */  if ((shmem_id = shmget (IPC_PRIVATE, (ngsmdevs * sizeof (struct gsms_def)),     (0660 | IPC_CREAT))) == -1)    syserr ("sms_serv: can't create shared memory segment");  if ((shared_memory = shmat (shmem_id, (void *)0, 0)) == (void *)-1)    syserr ("sms_serv: can't attach shared memory segment");  gsmdevices = (struct gsms_def *)shared_memory;    /* now initialize shared memory with GSM devices definition */  setgsmdevs;  for (i = 0; i < ngsmdevs; i++) {