gw_stuff.c

手机短消息的服务器端和客户端的源代码 是应用于LINUX/UNIX开发环境的

/*==========================================================
 * Program : gw_stuff.c                    Project : smslink
 * Author  : Philippe Andersson.
 * Date    : 01/03/00
 * Version : 0.16b
 * Notice  : (c) Les Ateliers du Heron, 1998 for Scitex Europe, S.A.
 * Comment : Library of functions for the smslink sms2mail gateway.
 *
 * Modification History :
 * - 0.01b (19/08/99) : Initial release. Moved the mail gateway-
 *   specific functions from stuff.c over here.
 * - 0.02b (28/09/99) : Created mailbox_run().
 * - 0.03b (29/09/99) : Extensive rework. Added tkize_ibox_line(),
 *   reset_mail_struct() and parse_smail().
 * - 0.04b (04/10/99) : Added expand_addr().
 * - 0.05b (17/10/99) : Expanded parse_smail() extensively.
 * - 0.06b (19/10/99) : Debugged tkize_ibox_line(). Increased
 *   debugging output. Created shell for send_mail().
 * - 0.07b (20/10/99) : Added mkfromfield().
 * - 0.08b (21/10/99) : Added is_dotted_quad () and resolve().
 * - 0.09b (08/11/99) : Built dialog in send_mail(). Added
 *   slurp_n_catch().
 * - 0.10b (09/11/99) : Modified parse_smail() to provide a
 *   default subject field if the SMS doesn't contain one. Involved
 *   alter the parameters passed to the function. Cosmetics.
 * - 0.11b (12/11/99) : Improved send_mail() to free() the
 *   allocated space for the nicified date.
 * - 0.12b (30/11/99) : Added temp file creation to mailbox_run().
 * - 0.13b (24/02/00) : Completed the transfer routine to the
 *   new mailbox file in mailbox_run().
 * - 0.14b (26/02/00) : Made sure the lockfile (MBOX_LOCKF) was
 *   deleted on each fatal error, as well as on SIGTERM being
 *   caught (in mailgws_death()). Improved error reporting in
 *   various functions. Cosmetics.
 * - 0.15b (29/02/00) : Added functions to handle recepients
 *   lists (as part of struct email_msg). Heavily modified most
 *   functions (send_mail(), parse_smail(), expand_addr()) and
 *   created sub_tkize_field() to account for changes in the
 *   email_msg struct.
 * - 0.16b (01/03/00) : Replaced the "old" slurp_n_catch() by
 *   a new version inspired by get_gsm_answer() (cf. serv_stuff.c).
 *   This should be more robust and less sensitive to the amount
 *   of data sent back by the server (here: sendmail). Created
 *   the clean_field() function (forgotten when split expand_addr()
 *   from sub_tkize_field()).
 *========================================================*/

#include <unistd.h>
#include <stdio.h>                         /* for fprintf */
#include <stdlib.h>                  /* for errno & stuff */
#include <errno.h>
#include <string.h>
#include <syslog.h>
#include <netdb.h>                 /* for gethostbyname() */
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/time.h>           /* for the struct timeval */
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/ioctl.h>            /* for the ioctl() call */
#ifdef LINUX_LC6
#  include <limits.h>                     /* for PATH_MAX */
#  include <linux/limits.h>
#else
#  include <limits.h>
#endif

#include "sms_serv.h"

/*========================================================*/
/* For debugging purposes only - comment out for normal compile */
/* #define INCL_DEBUG_CODE */

/*========================================================*/
void mailgws_death ()
{
  extern int inbox_is_locked;
  
  /* log it... */
  syslog ((FACILITY | LOG_INFO), "gateway exiting on SIGTERM.");
  
  /* remove inbox lock file if necessary */
  if (inbox_is_locked) {
    unlink (MBOX_LOCKF);
  }

  /* closes connection to the syslog daemon */
  closelog ();
  
  /* now exits gracefully */
  exit (0);
}                                     /* mailgws_death () */
/*========================================================*/
void rcpt_list_init (rcpt_list *list)
{
  list->head = NULL;
  list->tail = NULL;
}                                    /* rcpt_list_init () */
/*========================================================*/
int empty_rcpt_list (rcpt_list list)
{
  return (list.head == NULL);
}                                   /* empty_rcpt_list () */
/*========================================================*/
void rcpt_list_insert (rcpt_list *list, char *recepient)
{
  /* WARNING : the order of the elements might be relevent - let's
   * store them as they were in the header => avoid inserting at
   * list head. Do it at the tail. */
  
  int l;
  struct rcpt_item *element;

  /* alloc memory for new element */
  element = (struct rcpt_item *) malloc (sizeof (struct rcpt_item));
  if (!element) {
    syslog ((FACILITY | LOG_ERR), "can't malloc() for new RCPT entry.");
    unlink (MBOX_LOCKF);
    syserr ("sms2mailgw: can't malloc() for new RCPT entry");
  }
  
  /* initialize fields for new element */
  l = strlen (recepient);
  element->rcpt = (char *) malloc ((l + 1) * sizeof (char));
  if (!element->rcpt) {
    syslog ((FACILITY | LOG_ERR), "can't malloc() for new recepient string.");
    unlink (MBOX_LOCKF);
    syserr ("sms2mailgw: can't malloc() for new recepient string");
  }
  strcpy (element->rcpt, recepient);
  
  /* chain it in the list */
  if (empty_rcpt_list (*list)) {
    list->head = element;
    list->tail = element;
    element->next = NULL;
    element->prev = NULL;
  }
  else {
    element->next = NULL;
    element->prev = list->tail;
    list->tail->next = element;
    list->tail = element;
  }
}                                  /* rcpt_list_insert () */
/*========================================================*/
void free_rcpt_list (rcpt_list *list)
{
  struct rcpt_item *cursor;

  if (!empty_rcpt_list (*list)) {
    /* hop to element before last */
    cursor = list->tail->prev;
    /* now go back and clean behind */
    while (cursor != NULL) {
      free (cursor->next->rcpt);
      free (cursor->next);
      cursor->next = NULL;
      list->tail = cursor;
      cursor = cursor->prev;
    }                           /* while (cursor != NULL) */
  }                          /* if (!empty_rcpt_list (... */
  /* now clean last element and reset header */
  free (list->head->rcpt);
  free (list->head);
  list->head = NULL;
  list->tail = NULL;
}                                    /* free_rcpt_list () */
/*========================================================*/
#ifdef INCL_DEBUG_CODE
void print_rcpt_list (rcpt_list list)
{
  struct rcpt_item *cursor;

  if (!empty_rcpt_list (list)) {
    cursor = list.head;
    fprintf (stderr, "<%s>\n", cursor->rcpt);
    while (cursor->next != NULL) {
      cursor = cursor->next;
      fprintf (stderr, "<%s>\n", cursor->rcpt);
    }
  }
  else {
    fprintf (stderr, "sms2mailgw: empty recepient list.\n");
  }
}                                    /* print_acl_list () */
#endif
/*========================================================*/
int is_dotted_quad (char *string)
{
  int is_dq;
  char *s;
  int ntok = 0;
  char *ptok = NULL;
  long int ip_byte;
  char **endptr;
  char *dummyp;
  
  /*--------------------------------------Initializations */
  s = (char *) malloc ((strlen (string) + 1) * sizeof (char));
  if (! s) {
    syslog ((FACILITY | LOG_ERR), "can't malloc().");
    unlink (MBOX_LOCKF);
    syserr ("sms2mailgw: can't malloc()");
  }
  strcpy (s, string);
  /*--------------------------------------------Main Loop */
  /* no point going any further if the 1st char. is not a digit */
  is_dq = isdigit (string[0]);
  if (is_dq) {
    ptok = strtok (s, ".");
    while (ptok != NULL) {
      ntok++;
#ifdef INCL_DEBUG_CODE
      fprintf (stderr, "got token #%d : <%s>\n", ntok, ptok);
#endif
      dummyp = ptok + strlen (ptok);
      endptr = &dummyp;
      ip_byte = strtol (ptok, endptr, 10);
      if (strlen (*endptr) != 0) {
#ifdef INCL_DEBUG_CODE
	fprintf (stderr, "error on token #%d : can't convert <%s>\n", ntok, *endptr);
#endif
	is_dq = FALSE;
      }
      ptok = strtok (NULL, ".");
    }
    if (ntok != 4) {
      is_dq = FALSE;
    }
  }                                         /* if (is_dq) */
  /*------------------------------------------Conclusions */
  free (s);
  /*-------------------------------------------------Exit */
  return (is_dq);
}                                    /* is_dotted_quad () */
/*========================================================*/
unsigned long int resolve (char *host)
/* return the host ip address in network format */
{
  struct hostent *h_ent;
  struct in_addr target_ip;
  char **addrs;
  char *scratch;
  
  if (is_dotted_quad (host)) {
#ifdef INCL_DEBUG_CODE
    fprintf (stderr, "I think I got an IP address\n");
#endif
    if (inet_aton (host, &target_ip) == 0)
      syslog ((FACILITY | LOG_ERR), "invalid server IP address (%s).", host);
      scratch = (char *) malloc ((MINIBUFF + 1) * sizeof (char));
      sprintf (scratch, "sms2mailgw: invalid server IP address (%s)", host);
      herror (scratch);
      free (scratch);
      unlink (MBOX_LOCKF);
      exit (1);
  }
  else {
#ifdef INCL_DEBUG_CODE
    fprintf (stderr, "I think I got a host name\n");
#endif
    if ((h_ent = gethostbyname (host)) == NULL) {
      syslog ((FACILITY | LOG_ERR), "can't resolve hostname (%s).", host);
      scratch = (char *) malloc ((MINIBUFF + 1) * sizeof (char));
      sprintf (scratch, "sms2mailgw: can't resolve hostname (%s)", host);
      herror (scratch);
      free (scratch);
      unlink (MBOX_LOCKF);
      exit (1);
    }
    /* lines below cf. "Beginning Linux Progr.", pp. 468-473 */
    addrs = h_ent->h_addr_list;
    target_ip = *(struct in_addr *)*addrs;
#ifdef INCL_DEBUG_CODE
    fprintf (stderr, "server IP address is: [%s]\n", inet_ntoa (target_ip));
#endif
  }                             /* if (isdigit (host[0])) */
  return (target_ip.s_addr);
}                                           /* resolve () */
/*========================================================*/
int tkize_ibox_line (char *l, struct inbox_line *tkl)
{
  char *token;
  char *scratch;
  
  /*--------------------------------------Initializations */
  /* copy input string to scratch space - we can't modify it */
  scratch = (char *) malloc ((strlen (l) + 1) * sizeof (char));
  if (! scratch) {
    syslog ((FACILITY | LOG_ERR), "can't malloc().");
    unlink (MBOX_LOCKF);
    syserr ("sms2mailgw: can't malloc()");
  }
  scratch[0] = '\0';
  strcpy (scratch, l);
  
  /*--------------------------------------Parsing routine */
  /*...............................................Device */
  if ((token = strtok (scratch, ",")) == NULL) {
    return (-1);
  }
  strcpy (tkl->device, token);
  
  /*................................................MsgID */
  if ((token = strtok (NULL, ",")) == NULL) {
    return (-1);
  }
  tkl->msgid = atoi (token);
  
  /*..............................................FromGSM */
  if ((token = strtok (NULL, ",")) == NULL) {
    return (-1);
  }
  strcpy (tkl->fromgsm, token);
  
  /*.................................................Date */
  if ((token = strtok (NULL, ",")) == NULL) {
    return (-1);
  }
  strcpy (tkl->date, token);
  
  /*.................................................Time */
  if ((token = strtok (NULL, ",")) == NULL) {
    return (-1);
  }
  strcpy (tkl->time, token);
  
  /*.................................................Text */
  /* just grab the rest of the line */
  if ((token = strtok (NULL, "\0")) == NULL) {
    return (-1);
  }
  /* remove trailing LF */
  token[strlen (token) - 1] = '\0';
  dequote (token);
  strcpy (tkl->text, token);
  
  /*-------------------------------------------------Exit */
  free (scratch);
  return 0;                                    /* success */
}                                   /* tkize_ibox_line () */
/*========================================================*/
char *expand_addr (char *field, char *defdom)
{
  char *newstring;

  /*---------------------------------------Initialization */
  newstring = (char *) malloc ((BIGBUFF + 1) * sizeof (char));
  if (! newstring) {
    syslog ((FACILITY | LOG_ERR), "can't malloc().");
    unlink (MBOX_LOCKF);
    syserr ("sms2mailgw: can't malloc()");
  }
  newstring[0] = '\0';
  
  /*---------------------------------Main processing loop */
  if (strchr (field, '@') == NULL) {
    sprintf (newstring, "%s@%s", field, defdom);
  }
  else {
    strcpy (newstring, field);
  }
  /*------------------------------------------Conclusions */
#ifdef INCL_DEBUG_CODE
  fprintf (stderr, "expanded field: [%s]\n", newstring);
#endif
  return (newstring);
}                                       /* expand_addr () */
/*========================================================*/
char *clean_field (char *field)
/* For fields that cannot be multi-part (Reply-to:), remove
 * the field header and any additional address. */
{
  char *ptr;
  
  /* The field for sure has a field header - skip it */
  shiftleft (field, 2);
  /* If the first char now is a space, skip that as well */
  if (field[0] == ' ') {
    shiftleft (field, 1);
  }
  /* If the field contains a comma, kill it and all that follows */
  if ((ptr = strchr (field, ',')) != NULL) {
    ptr[0] = '\0';
  }
  
  return (field);
}                                       /* clean_field () */
/*========================================================*/
int sub_tkize_field (rcpt_list *list, char *field, char *defdom)
{
  int nfields = 0;
  char *s;
  char *ptr;
  char *newstring;
  char *item;
  
  /*---------------------------------------Initialization */
  /* take a local copy of "field" to avoid it being modified */
  s = (char *) malloc ((strlen (field) + 1) * sizeof (char));
  if (! s) {
    syslog ((FACILITY | LOG_ERR), "can't malloc().");
    unlink (MBOX_LOCKF);
    syserr ("sms2mailgw: can't malloc()");
  }
  s[0] = '\0';
  strcpy (s, field);
  ptr = s;
  
  /* s for sure has a field header ("T:" for inst.) - skip it */
  ptr += 2;
  /* if there was a blank between the header and the field, skip it too */
  if (ptr[0] == ' ') {
    ptr++;
  }
  
  /*---------------------------------Main processing loop */
  if ((item = strtok (ptr, ",")) == NULL) {
    /* field header w/o contents */
    free (s);
    return (nfields);
  }
  /* process first item */
  newstring = expand_addr (item, defdom);
  rcpt_list_insert (list, newstring);
  nfields++;
  free (newstring);
  
  /* now tokenize and process the rest */
  while ((item = strtok (NULL, ",")) != NULL) {