clean up awk syntax

[unix-history] / usr / src / libexec / tftpd / tftpd.c

diff --git a/usr/src/libexec/tftpd/tftpd.c b/usr/src/libexec/tftpd/tftpd.c
index 49dc9d0..9a9529e 100644 (file)
--- a/usr/src/libexec/tftpd/tftpd.c
+++ b/usr/src/libexec/tftpd/tftpd.c
@@ -11,7 +11,7 @@ char copyright[] =
 #endif not lint
 
 #ifndef lint
 #endif not lint
 
 #ifndef lint

-static char sccsid[] = "@(#)tftpd.c    5.3 (Berkeley) %G%";
+static char sccsid[] = "@(#)tftpd.c    5.6 (Berkeley) %G%";

 #endif not lint
 
 
 #endif not lint
 
 


@@ -57,31 +57,85 @@ main()
 {
        register struct tftphdr *tp;
        register int n;
 {
        register struct tftphdr *tp;
        register int n;

+       int on = 1;

 
        openlog("tftpd", LOG_PID, LOG_DAEMON);
 
        openlog("tftpd", LOG_PID, LOG_DAEMON);

-       alarm(10);
+       if (ioctl(0, FIONBIO, &on) < 0) {
+               syslog(LOG_ERR, "ioctl(FIONBIO): %m\n");
+               exit(1);
+       }

        fromlen = sizeof (from);
        n = recvfrom(0, buf, sizeof (buf), 0,
            (caddr_t)&from, &fromlen);
        if (n < 0) {
        fromlen = sizeof (from);
        n = recvfrom(0, buf, sizeof (buf), 0,
            (caddr_t)&from, &fromlen);
        if (n < 0) {

-               perror("tftpd: recvfrom");
+               syslog(LOG_ERR, "recvfrom: %m\n");

                exit(1);
        }
                exit(1);
        }

+       /*
+        * Now that we have read the message out of the UDP
+        * socket, we fork and exit.  Thus, inetd will go back
+        * to listening to the tftp port, and the next request
+        * to come in will start up a new instance of tftpd.
+        *
+        * We do this so that inetd can run tftpd in "wait" mode.
+        * The problem with tftpd running in "nowait" mode is that
+        * inetd may get one or more successful "selects" on the
+        * tftp port before we do our receive, so more than one
+        * instance of tftpd may be started up.  Worse, if tftpd
+        * break before doing the above "recvfrom", inetd would
+        * spawn endless instances, clogging the system.
+        */
+       {
+               int pid;
+               int i, j;
+
+               for (i = 1; i < 20; i++) {
+                   pid = fork();
+                   if (pid < 0) {
+                               sleep(i);
+                               /*
+                                * flush out to most recently sent request.
+                                *
+                                * This may drop some request, but those
+                                * will be resent by the clients when
+                                * they timeout.  The positive effect of
+                                * this flush is to (try to) prevent more
+                                * than one tftpd being started up to service
+                                * a single request from a single client.
+                                */
+                               j = sizeof from;
+                               i = recvfrom(0, buf, sizeof (buf), 0,
+                                   (caddr_t)&from, &j);
+                               if (i > 0) {
+                                       n = i;
+                                       fromlen = j;
+                               }
+                   } else {
+                               break;
+                   }
+               }
+               if (pid < 0) {
+                       syslog(LOG_ERR, "fork: %m\n");
+                       exit(1);
+               } else if (pid != 0) {
+                       exit(0);
+               }
+       }

        from.sin_family = AF_INET;
        alarm(0);
        close(0);
        close(1);
        peer = socket(AF_INET, SOCK_DGRAM, 0);
        if (peer < 0) {
        from.sin_family = AF_INET;
        alarm(0);
        close(0);
        close(1);
        peer = socket(AF_INET, SOCK_DGRAM, 0);
        if (peer < 0) {

-               syslog(LOG_ERR, "socket: %m");
+               syslog(LOG_ERR, "socket: %m\n");

                exit(1);
        }
        if (bind(peer, (caddr_t)&sin, sizeof (sin)) < 0) {
                exit(1);
        }
        if (bind(peer, (caddr_t)&sin, sizeof (sin)) < 0) {

-               syslog(LOG_ERR, "bind: %m");
+               syslog(LOG_ERR, "bind: %m\n");

                exit(1);
        }
        if (connect(peer, (caddr_t)&from, sizeof(from)) < 0) {
                exit(1);
        }
        if (connect(peer, (caddr_t)&from, sizeof(from)) < 0) {

-               syslog(LOG_ERR, "connect: %m");
+               syslog(LOG_ERR, "connect: %m\n");

                exit(1);
        }
        tp = (struct tftphdr *)buf;
                exit(1);
        }
        tp = (struct tftphdr *)buf;


@@ -234,17 +288,18 @@ sendfile(pf)
                timeout = 0;
                (void) setjmp(timeoutbuf);
 
                timeout = 0;
                (void) setjmp(timeoutbuf);
 

+send_data:

                if (send(peer, dp, size + 4, 0) != size + 4) {
                if (send(peer, dp, size + 4, 0) != size + 4) {

-                       perror("tftpd: write");
+                       syslog(LOG_ERR, "tftpd: write: %m\n");

                        goto abort;
                }
                read_ahead(file, pf->f_convert);
                        goto abort;
                }
                read_ahead(file, pf->f_convert);

-               do {
+               for ( ; ; ) {

                        alarm(rexmtval);        /* read the ack */
                        n = recv(peer, ackbuf, sizeof (ackbuf), 0);
                        alarm(0);
                        if (n < 0) {
                        alarm(rexmtval);        /* read the ack */
                        n = recv(peer, ackbuf, sizeof (ackbuf), 0);
                        alarm(0);
                        if (n < 0) {

-                               perror("tftpd: read");
+                               syslog(LOG_ERR, "tftpd: read: %m\n");

                                goto abort;
                        }
                        ap->th_opcode = ntohs((u_short)ap->th_opcode);
                                goto abort;
                        }
                        ap->th_opcode = ntohs((u_short)ap->th_opcode);


@@ -252,8 +307,19 @@ sendfile(pf)
 
                        if (ap->th_opcode == ERROR)
                                goto abort;
 
                        if (ap->th_opcode == ERROR)
                                goto abort;

+                       
+                       if (ap->th_opcode == ACK) {
+                               if (ap->th_block == block) {
+                                       break;
+                               }
+                               /* Re-synchronize with the other side */
+                               (void) synchnet(peer);
+                               if (ap->th_block == (block -1)) {
+                                       goto send_data;
+                               }
+                       }

 
 

-               }  while (ap->th_opcode != ACK || ap->th_block != block);
+               }

                block++;
        } while (size == SEGSIZE);
 abort:
                block++;
        } while (size == SEGSIZE);
 abort:


@@ -287,7 +353,7 @@ recvfile(pf)
                (void) setjmp(timeoutbuf);
 send_ack:
                if (send(peer, ackbuf, 4, 0) != 4) {
                (void) setjmp(timeoutbuf);
 send_ack:
                if (send(peer, ackbuf, 4, 0) != 4) {

-                       perror("tftpd: write");
+                       syslog(LOG_ERR, "tftpd: write: %m\n");

                        goto abort;
                }
                write_behind(file, pf->f_convert);
                        goto abort;
                }
                write_behind(file, pf->f_convert);


@@ -296,7 +362,7 @@ send_ack:
                        n = recv(peer, dp, PKTSIZE, 0);
                        alarm(0);
                        if (n < 0) {            /* really? */
                        n = recv(peer, dp, PKTSIZE, 0);
                        alarm(0);
                        if (n < 0) {            /* really? */

-                               perror("tftpd: read");
+                               syslog(LOG_ERR, "tftpd: read: %m\n");

                                goto abort;
                        }
                        dp->th_opcode = ntohs((u_short)dp->th_opcode);
                                goto abort;
                        }
                        dp->th_opcode = ntohs((u_short)dp->th_opcode);


@@ -307,6 +373,8 @@ send_ack:
                                if (dp->th_block == block) {
                                        break;   /* normal */
                                }
                                if (dp->th_block == block) {
                                        break;   /* normal */
                                }

+                               /* Re-synchronize with the other side */
+                               (void) synchnet(peer);

                                if (dp->th_block == (block-1))
                                        goto send_ack;          /* rexmit */
                        }
                                if (dp->th_block == (block-1))
                                        goto send_ack;          /* rexmit */
                        }


@@ -383,5 +451,5 @@ nak(error)
        tp->th_msg[length] = '\0';
        length += 5;
        if (send(peer, buf, length, 0) != length)
        tp->th_msg[length] = '\0';
        length += 5;
        if (send(peer, buf, length, 0) != length)

-               perror("nak");
+               syslog(LOG_ERR, "nak: %m\n");

 }
 }