[unix-history] / usr / src / usr.sbin / sendmail / src / daemon.c

# include <errno.h>
# include "sendmail.h"
# include <sys/mx.h>

#ifndef DAEMON
SCCSID(@(#)daemon.c     3.46            %G%     (w/o daemon mode));
#else

#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <wait.h>

SCCSID(@(#)daemon.c     3.46            %G%     (with daemon mode));

/*
**  DAEMON.C -- routines to use when running as a daemon.
**
**      This entire file is highly dependent on the 4.2 BSD
**      interprocess communication primitives.  No attempt has
**      been made to make this file portable to Version 7,
**      Version 6, MPX files, etc.  If you should try such a
**      thing yourself, I recommend chucking the entire file
**      and starting from scratch.  Basic semantics are:
**
**      getrequests()
**              Opens a port and initiates a connection.
**              Returns in a child.  Must set InChannel and
**              OutChannel appropriately.
**      clrdaemon()
**              Close any open files associated with getting
**              the connection; this is used when running the queue,
**              etc., to avoid having extra file descriptors during
**              the queue run and to avoid confusing the network
**              code (if it cares).
**      makeconnection(host, port, outfile, infile)
**              Make a connection to the named host on the given
**              port.  Set *outfile and *infile to the files
**              appropriate for communication.  Returns zero on
**              success, else an exit status describing the
**              error.
**
**      The semantics of both of these should be clean.
*/

static FILE     *MailPort;      /* port that mail comes in on */
\f/*
**  GETREQUESTS -- open mail IPC port and get requests.
**
**      Parameters:
**              none.
**
**      Returns:
**              none.
**
**      Side Effects:
**              Waits until some interesting activity occurs.  When
**              it does, a child is created to process it, and the
**              parent waits for completion.  Return from this
**              routine is always in the child.  The file pointers
**              "InChannel" and "OutChannel" should be set to point
**              to the communication channel.
*/

struct sockaddr_in      SendmailAddress;/* internet address of sendmail */
int     DaemonSocket = -1;              /* fd describing socket */
int     MaxConnections = 4;             /* maximum simultaneous sendmails */

getrequests()
{
       int t;
       union wait status;
       int numconnections = 0;
       register struct servent *sp;

       /*
       **  Set up the address for the mailer.
       */

       sp = getservbyname("smtp", "tcp");
       if (sp == NULL)
       {
               syserr("server \"smtp\" unknown");
               goto severe;
       }
       SendmailAddress.sin_family = AF_INET;
       SendmailAddress.sin_addr.s_addr = INADDR_ANY;
       SendmailAddress.sin_port = sp->s_port;

       /*
       **  Try to actually open the connection.
       */

# ifdef DEBUG
       if (tTd(15, 1))
               printf("getrequests: port 0x%x\n", SendmailAddress.sin_port);
# endif DEBUG

       /* get a socket for the SMTP connection */
       DaemonSocket = socket(AF_INET, SOCK_STREAM, 0, 0);
       if (DaemonSocket < 0)
       {
               /* probably another daemon already */
               syserr("getrequests: can't create socket");
         severe:
# ifdef LOG
               if (LogLevel > 0)
                       syslog(LOG_SALERT, "cannot get connection");
# endif LOG
               finis();
       }

#ifdef DEBUG
       /* turn on network debugging? */
       if (tTd(15, 15))
               (void) setsockopt(DaemonSocket, SOL_SOCKET, SO_DEBUG, 0, 0);
#endif DEBUG

       if (bind(DaemonSocket, &SendmailAddress, sizeof SendmailAddress, 0) < 0)
       {
               syserr("getrequests: cannot bind");
               (void) close(DaemonSocket);
               goto severe;
       }
       listen(DaemonSocket, 10);

# ifdef DEBUG
       if (tTd(15, 1))
               printf("getrequests: %d\n", DaemonSocket);
# endif DEBUG

       struct wh wbuf;

       wbuf.index = index;
       wbuf.count = 0;
       wbuf.ccount = cnt;
       wbuf.data = buf;
       write(MailPort, &wbuf, sizeof wbuf);
}
\f/*
**  MAKECONNECTION -- make a connection to an SMTP socket on another machine.
**
**      Parameters:
**              host -- the name of the host.
**              port -- the port number to connect to.
**              outfile -- a pointer to a place to put the outfile
**                      descriptor.
**              infile -- ditto for infile.
**
**      Returns:
**              An exit code telling whether the connection could be
**                      made and if not why not.
**
**      Side Effects:
**              none.
*/

makeconnection(host, port, outfile, infile)
       char *host;
       u_short port;
       FILE **outfile;
       FILE **infile;
{
       register int s;

       /*
       **  Set up the address for the mailer.
       **      Accept "[a.b.c.d]" syntax for host name.
       */

       if (host[0] == '[')
       {
               long hid = 0;
               int i, j;
               register char *p = host;

               for (i = 3; i >= 0 && *p != ']' && *p != '\0'; i--)
               {
                       j = 0;
                       while (isdigit(*++p))
                               j = j * 10 + (*p - '0');
                       if (*p != (i == 0 ? ']' : '.') || j > 255 || j < 0)
                               break;
                       hid |= j << ((3 - i) * 8);
               }
               if (i >= 0 || *p != ']' || *++p != '\0')
               {
                       usrerr("Invalid numeric domain spec \"%s\"", host);
                       return (EX_NOHOST);
               }
               SendmailAddress.sin_addr.s_addr = hid;
       }
       else
       {
               register struct hostent *hp = gethostbyname(host);

               if (hp == 0)
                       return (EX_NOHOST);
               bmove(hp->h_addr, (char *) &SendmailAddress.sin_addr, hp->h_length);
       }

       /*
       **  Determine the port number.
       */

       if (port != 0)
               SendmailAddress.sin_port = htons(port);
       else
       {
               register struct servent *sp = getservbyname("smtp", "tcp");

               if (sp == NULL)
               {
                       syserr("makeconnection: server \"smtp\" unknown");
                       return (EX_OSFILE);
               }
               SendmailAddress.sin_port = sp->s_port;
       }

       /*
       **  Try to actually open the connection.
       */

# ifdef DEBUG
       if (tTd(16, 1))
               printf("makeconnection (%s)\n", host);
# endif DEBUG

#ifdef NVMUNIX
       s = socket(AF_INET, SOCK_STREAM, 0, 0);
#else NVMUNIX
       s = socket(AF_INET, SOCK_STREAM, 0, 0);
#endif NVMUNIX
       if (s < 0)
       {
               syserr("makeconnection: no socket");
               goto failure;
       }

# ifdef DEBUG
       if (tTd(16, 1))
               printf("makeconnection: %d\n", s);

       /* turn on network debugging? */
       if (tTd(16, 14))
               (void) setsockopt(s, SOL_SOCKET, SO_DEBUG, 0, 0);
# endif DEBUG
       (void) fflush(CurEnv->e_xfp);                   /* for debugging */
#ifdef NVMUNIX
       bind(s, &SendmailAddress, sizeof SendmailAddress, 0);
       if (connect(s, &SendmailAddress, sizeof SendmailAddress, 0) < 0)
#else NVMUNIX
       SendmailAddress.sin_family = AF_INET;
       bind(s, &SendmailAddress, sizeof SendmailAddress, 0);
       if (connect(s, &SendmailAddress, sizeof SendmailAddress, 0) < 0)
#endif NVMUNIX
       {
               /* failure, decide if temporary or not */
       failure:
               switch (errno)
               {
                 case EISCONN:
                 case ETIMEDOUT:
                 case EINPROGRESS:
                 case EALREADY:
                 case EADDRINUSE:
                 case EHOSTDOWN:
                 case ENETDOWN:
                 case ENETRESET:
                 case ENOBUFS:
                 case ECONNREFUSED:
                 case EHOSTUNREACH:
                 case ENETUNREACH:
                       /* there are others, I'm sure..... */
                       return (EX_TEMPFAIL);

                 default:
                       return (EX_UNAVAILABLE);
               }
       }

       /* connection ok, put it into canonical form */
       *outfile = fdopen(s, "w");
       *infile = fdopen(s, "r");

       return (EX_OK);
}

#endif DAEMON