mail.c

Linux系统备份源代码 可基于用户自定义策略实现系统、应用数据备份

/***************************************************************************
    filename             : mail.c
    begin                : Sun Nov 25 2001
    copyright            : (C) 2001 by Henrik Witt-Hansen
    email                : [e-mail]
 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   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.                                   *
 *                                                                         *
 ***************************************************************************/



/*base configuration*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif



/*standard includes*/
#include <stdio.h>
#include <pthread.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>



/*local headers*/
#include "sitback.h"



/*special includes*/
#include <sys/errno.h>
#include <time.h>
#include <sys/ioctl.h>
#include <signal.h>
#include <sys/wait.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/ipc.h>
#include <sys/sem.h>
#include <sys/time.h>
#include <netinet/in.h>
#include <sys/wait.h>
#include <netdb.h>
#include <arpa/inet.h>



/*local prototypes*/
int __socket_command(int clientsocket,char *send,char *expect);



/*local data*/
extern int errno;



/********************************************************************
  int SendMail()

  Send a mail with the content of some file

  arguments:
    file;     Name of file with message
    subject;  The subject line
  return:
    0 on success
    -1 on error
********************************************************************/
int SendMail(char *file,char *subject)
{
  int clientsocket;
  struct sockaddr_in dest_addr;
  struct hostent *h;
  char hostname[1024];
  char hosts_entry[1024];
  char domainname[1024];
  char msg[1024];
  FILE *fd;
  char buffer[4096];
  char *p;
  int state=0;
  int lookup_retry=0;
  struct hostent *myhost;
  time_t now;
  char date[256];
  struct tm *now_tm;
  unsigned char CR = 0;


  if(conf__smtp_host[0]!='\0')
  {
    /* get our local hostname */
    if(gethostname(hostname,1024))
    {
      debug("Unable to get our local hostname\n");
      log("Unable to get local hostname\n");
      return -1;
    }
    debug("Hostname '%s'\n",hostname);


    /* Try to locate a line in '/etc/hosts' with this hostname */
    do
    {
      myhost = gethostent();
      if( snprintf(hosts_entry,1024,"%s",myhost->h_name)<=0 )
      {
        debug("Unable to get full hostname with gethostent()\n");
        log("Unable to get the full host- and domainname. Check '/etc/hosts'\n");
        return -1;
      }
      debug("gethostent: '%s'\n",hosts_entry);
    }
    while( memcmp(hosts_entry,hostname,strlen(hostname)) );
    debug("Got the right line from /etc/hosts\n");
    strcpy(hostname,hosts_entry);


    /* Make sure we have a sane hostname */
    if(strchr(hostname,'.')==NULL)
    {
      debug("Hostname not complete (missing domain).\n");
      if(getdomainname(domainname,1024-strlen(hostname)-1))
      {
        debug("Unable to get our local domainname\n");
        log("Unable to get local domainname\n");
        return -1;
      }


      /* Check that the domainname is ok */
      if(!strcmp(domainname,"(none)"))
      {
        UI__Warning("  Invalid hostname and/or domainname.\n  'hostname' does not return a full host+domain name,\n  and trying to obtain your domainname with\n  'domainname' failed\n");
        log("Invalid host and/or domainname. Check network settings\n");
        Report("Invalid host and/or domainname. Check network settings\n");
        return -1;
      }


      /* Combine host and domainname */
      strcat(hostname,".");
      strcat(hostname,domainname);
      debug("Hostname seems to be '%s'\n",hostname);
    }
    debug("Full hostname is '%s'\n",hostname);


    /* Resolv smtp hostname */
    RETRY_TRANSFER:
    if((h=gethostbyname(conf__smtp_host))==NULL)
    {
      debug("Host lookup failure for '%s'\n",conf__smtp_host);
      if(lookup_retry<3)
      {
        debug("Retrying host lookup in case we have a slow dialup connection\n");
        lookup_retry++;
        goto RETRY_TRANSFER;
      }
      log("Host lookup failure for '%s'",conf__smtp_host);
      return -1;
    }
    debug("smtp host ip: %s\n",inet_ntoa(*((struct in_addr *)h->h_addr)));


    /* get a brand new socket */
    if((clientsocket = socket(AF_INET, SOCK_STREAM, 0))==-1)
    {
      debug("Unable to create tcp/ip socket\n");
      log("Unable to create tcp/ip socket\n");
      return -1;
    }
    debug("Got tcp/ip socket\n");


    /* Prepare to connect */
    dest_addr.sin_family = AF_INET;
    dest_addr.sin_port = htons(25);
    dest_addr.sin_addr.s_addr = inet_addr(inet_ntoa(*((struct in_addr *)h->h_addr)));
    bzero(&(dest_addr.sin_zero), 8);


    /* connect */
    if(connect(clientsocket, (struct sockaddr *)&dest_addr, sizeof(struct sockaddr))==-1)
    {
      debug("Unable to connect\n");
      close(clientsocket);
      return -1;
    }
    debug("Connected\n");


    /* First, the smtp server must send us a HELO with code 220 */
    debug("Receiving initial HELO\n");
    if(__socket_command(clientsocket,NULL,"220"))
    {
      debug("Unexpected answer from the server\n");
      close(clientsocket);
      return -1;
    }


    /* now send a HELO with our hostname, expect 250 in return */
    sprintf(msg,"HELO %s\r\n",hostname);
    debug("Sending HELO: %s",msg);
    if(__socket_command(clientsocket,msg,"250"))
    {
      debug("Unexpected answer from the server\n");
      log("Unexpected answer from server (HELO %s)",msg);
      close(clientsocket);
      return -1;
    }


    /* username/password ?? */
    if(conf__smtp_user[0]!='\0' && conf__smtp_pass[0]!='\0')
    {
      /* Request authentication */
      sprintf(msg,"AUTH LOGIN\r\n");
      debug("Request authentication: %s",msg);
      if(__socket_command(clientsocket,msg,"334"))
      {
        debug("Unexpected answer from the server\n");
        log("Server can not do smtp authentication");
        goto MAIL_TRANSFER;
      }


      /* Send username */
      sprintf(msg,"%s\r\n",conf__smtp_user);
      debug("Sending username: %s",msg);
      if(__socket_command(clientsocket,msg,"334"))
      {
        debug("Unexpected answer from the server\n");
        log("User unknown");
        close(clientsocket);
        return -1;
      }


      /* Send password */
      sprintf(msg,"%s\r\n",conf__smtp_pass);
      debug("Sending password: %s",msg);
      if(__socket_command(clientsocket,msg,"235"))
      {
        debug("Unexpected answer from the server\n");
        log("Incorrect password");
        close(clientsocket);
        return -1;
      }
    }


    /* Prepare mail transfer */
    MAIL_TRANSFER:
    sprintf(msg,"MAIL FROM:<sitback@%s>\r\n",strchr(hostname,'.')+1);
    debug("Prepare mail transfer: %s",msg);
    if(__socket_command(clientsocket,msg,"250"))
    {
      debug("Unexpected answer from the server\n");
      log("Sender address not accepted by mailserver");
      close(clientsocket);
      return -1;
    }


    /* Recipient */
    sprintf(msg,"RCPT TO:<%s>\r\n",conf__report_mail);
    debug("Recipient: %s",msg);
    if(__socket_command(clientsocket,msg,"250"))
    {
      debug("Unexpected answer from the server\n");
      log("Recipient not accepted by mailserver (%s)",msg);
      close(clientsocket);
      return -1;
    }


    /* Ready to start */
    sprintf(msg,"DATA\r\n");
    debug("Starting mail transfer: %s",msg);
    if(__socket_command(clientsocket,msg,"354"))
    {
      debug("Unexpected answer from the server\n");
      close(clientsocket);
      return -1;
    }


    /* From field in the mail */
    sprintf(msg,"From: sitback@%s\r\n",strchr(hostname,'.')+1);
    debug("From field: %s",msg);
    if(__socket_command(clientsocket,msg,NULL))
    {
      debug("Error while talking to the mailserver\n");
      close(clientsocket);
      return -1;
    }


    /* To field in the mail */
    sprintf(msg,"To: %s\r\n",conf__report_mail);
    debug("To field: %s",msg);
    if(__socket_command(clientsocket,msg,NULL))
    {
      debug("Error while talking to the mailserver\n");
      close(clientsocket);
      return -1;
    }


    /* Subject field in the mail */
    sprintf(msg,"Subject: %s - %s\r\n",subject,hostname);
    debug("Subject field: %s",msg);
    if(__socket_command(clientsocket,msg,NULL))
    {
      debug("Error while talking to the mailserver\n");
      close(clientsocket);
      return -1;
    }


    /* Date field in the mail */
    now = time(NULL);
    now_tm = localtime(&now);
    strftime(date,256,"%a,  %d  %b  %Y  %H:%M:%S  %z",now_tm);
    sprintf(msg,"Date: %s\r\n",date);
    debug("Date field: %s",msg);
    if(__socket_command(clientsocket,msg,NULL))
    {
      debug("Error while talking to the mailserver\n");
      close(clientsocket);
      return -1;
    }


    /* Send the report */
    if((fd=fopen(file,"r"))==NULL)
    {
      debug("Unable to open the specified file '%s'\n",file);
      if(__socket_command(clientsocket,"(Internal error: Unable to open the report)\r\n",NULL))
      {
        debug("Error while talking to the mailserver\n");
        close(clientsocket);
        return -1;
      }
    }
    else
    {
      debug("Transmitting report file '%s'\n",file);
      for(;;)
      {
        /* Get a chunk */
        memset(buffer,'\0',1025);
        fread(buffer,1024,1,fd);

        /* Check for standalone linefeeds */
        p=buffer;
        while( *p!='\0' )
        {
          if( *p=='\r' )
          {
            CR = 1;
          }
          else if( *p=='\n' && CR==0 )
          {
            memmove(p+1,p,strlen(p)+1);
            *p = '\r';
            p++;
          }
          else
            CR = 0;
          p++;
        }

        /* Send the buffer */
        if(__socket_command(clientsocket,buffer,NULL))
        {
          debug("Error while talking to the mailserver\n");
          close(clientsocket);
          fclose(fd);
          return -1;
        }

        /* Anymore data ?? */
        if(feof(fd))
          break;
      }
      fclose(fd);
    }


    /* Ending mail transfer */
    sprintf(msg,"\r\n.\r\n");
    debug("Ending mail transfer\n");
    if(__socket_command(clientsocket,msg,"250"))
    {
      debug("Unexpected answer from the server\n");
      close(clientsocket);
      return -1;
    }


    /* Close connection */
    sprintf(msg,"QUIT\r\n");
    debug("Sending QUIT\n");
    if(__socket_command(clientsocket,msg,"221"))
    {
      debug("Unexpected answer from the server\n");
      close(clientsocket);
      return -1;
    }


    /* close the socket */
    debug("Closing socket\n");
    close(clientsocket);
  }


  /* done */
  return 0;
}



/********************************************************************
  int __socket_command()

  Send on a socket, thereafter receive an answer
  and compare agains an 'expected' string


  arguments:
    clientsocket:  The socket to use
    send;          String to send, NULL if nothing is to be send
    expect;        Receive an answer and compare to this string
  returns:
    0 on success
    1 if compare fails
    -1 on error
********************************************************************/
int __socket_command(int clientsocket,char *send,char *expect)
{
  int rc;
  unsigned len;
  char recv[1025];
  int result=0;
  fd_set rfds;
  struct timeval tv;


  /* paranoid check */
  if(expect!=NULL && strlen(expect)>1024)
  {
    debug("Internal error: Unable to compare more than 1024 characters\n");
    return -1;
  }


  /* Anything to send ?? */
  if(send!=NULL)
  {
    len=0;
    while(len<strlen(send))
    {
      if((rc=write(clientsocket,send,strlen(send)))==-1)
      {
        debug("Error in write(), '%s'\n",strerror(errno));
        return -1;
      }
      len+=rc;
      debug("rc=%d  len=%u\n",rc,len);
    }
  }


  /* should we try to receive an answer ?? */
  if(expect!=NULL)
  {
    /* wait until some data is available, or timeout */
    debug("Waiting until there is data on the socket\n");
    FD_ZERO(&rfds);
    FD_SET(clientsocket,&rfds);
    tv.tv_sec=30;
    tv.tv_usec=0;
    if(select(clientsocket+1,&rfds,NULL,NULL,&tv)<1)
    {
      debug("Timeout waiting for answer on socket\n");
      return -1;
    }


    /* Read some data */
    debug("Receiving answer\n");
    if((rc=read(clientsocket,recv,1024))==-1)
    {
      debug("Error in read(), '%s'\n",strerror(errno));
      return -1;
    }
    recv[rc]='\0';


    /* compare */
    debug("expect: %s\n",expect);
    debug("recv: %s",recv);
    if(rc<strlen(expect))
      result=1;
    else if(memcmp(recv,expect,strlen(expect)))
      result=1;
    debug("result=%d\n",result);


    /* Keep receiving if there is more data on the socket */
    if(rc==1024)
    {
      debug("Trying to clean the socket\n");
      for(;;)
      {
        /* wait until some data is available, or timeout */
        debug("Waiting until there is data on the socket\n");
        FD_ZERO(&rfds);
        FD_SET(clientsocket,&rfds);
        tv.tv_sec=3;
        tv.tv_usec=0;
        if(select(clientsocket+1,&rfds,NULL,NULL,&tv)<1)
        {
          debug("No more data on the socket (timeout)\n");
          break;
        }


        /* Read some data */
        debug("Receiving answer\n");
        if((rc=read(clientsocket,recv,1024))==-1)
        {
          debug("Error in read(), '%s'\n",strerror(errno));
          return -1;
        }
        debug("rc=%d\n",rc);
        recv[rc]='\0';
        debug("Received: '%s'\n",recv);
        if(rc!=1024)
        {
          debug("No more data\n");
          break;
        }
      }
    }
  }


  /* done */
  return result;
}