support Deflate and Predictor; shut up if we receive an empty
authorPaul Mackerras <paulus@samba.org>
Fri, 27 Oct 1995 03:42:52 +0000 (03:42 +0000)
committerPaul Mackerras <paulus@samba.org>
Fri, 27 Oct 1995 03:42:52 +0000 (03:42 +0000)
configure-reject.

pppd/ccp.c

index ae6795228c64655c07e427ae6f944213631ce7b3..355ba1d9450709e20f80e018b42e30da810734d3 100644 (file)
@@ -26,7 +26,7 @@
  */
 
 #ifndef lint
-static char rcsid[] = "$Id: ccp.c,v 1.11 1995/08/16 04:15:38 paulus Exp $";
+static char rcsid[] = "$Id: ccp.c,v 1.12 1995/10/27 03:42:52 paulus Exp $";
 #endif
 
 #include <syslog.h>
@@ -79,10 +79,11 @@ static fsm_callbacks ccp_callbacks = {
 /*
  * Do we want / did we get any compression?
  */
-#define ANY_COMPRESS(opt)      ((opt).bsd_compress)
+#define ANY_COMPRESS(opt)      ((opt).deflate || (opt).bsd_compress \
+                                || (opt).predictor_1 || (opt).predictor_2)
 
 /*
- * Local state (mainly for handling reset-reqs and reset-acks
+ * Local state (mainly for handling reset-reqs and reset-acks).
  */
 static int ccp_localstate[NUM_PPP];
 #define RACK_PENDING   1       /* waiting for reset-ack */
@@ -90,6 +91,8 @@ static int ccp_localstate[NUM_PPP];
 
 #define RACKTIMEOUT    1       /* second */
 
+static int all_rejected[NUM_PPP];      /* we rejected all peer's options */
+
 /*
  * ccp_init - initialize CCP.
  */
@@ -243,17 +246,44 @@ static void
 ccp_resetci(f)
     fsm *f;
 {
+    int ok;
     ccp_options *go = &ccp_gotoptions[f->unit];
     u_char opt_buf[16];
 
     *go = ccp_wantoptions[f->unit];
+    all_rejected[f->unit] = 0;
+
+    /*
+     * Check whether the kernel knows about the various
+     * compression methods we might request.
+     */
     if (go->bsd_compress) {
        opt_buf[0] = CI_BSD_COMPRESS;
        opt_buf[1] = CILEN_BSD_COMPRESS;
-       opt_buf[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, go->bsd_bits);
-       if (!ccp_test(f->unit, opt_buf, CILEN_BSD_COMPRESS, 0))
+       opt_buf[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, BSD_MIN_BITS);
+       if (ccp_test(f->unit, opt_buf, CILEN_BSD_COMPRESS, 0) <= 0)
            go->bsd_compress = 0;
     }
+    if (go->deflate) {
+       opt_buf[0] = CI_DEFLATE;
+       opt_buf[1] = CILEN_DEFLATE;
+       opt_buf[2] = DEFLATE_MAKE_OPT(DEFLATE_MIN_SIZE);
+       opt_buf[3] = DEFLATE_CHK_SEQUENCE;
+       if (ccp_test(f->unit, opt_buf, CILEN_DEFLATE, 0) <= 0)
+           go->deflate = 0;
+    }
+    if (go->predictor_1) {
+       opt_buf[0] = CI_PREDICTOR_1;
+       opt_buf[1] = CILEN_PREDICTOR_1;
+       if (ccp_test(f->unit, opt_buf, CILEN_PREDICTOR_1, 0) <= 0)
+           go->predictor_1 = 0;
+    }
+    if (go->predictor_2) {
+       opt_buf[0] = CI_PREDICTOR_2;
+       opt_buf[1] = CILEN_PREDICTOR_2;
+       if (ccp_test(f->unit, opt_buf, CILEN_PREDICTOR_2, 0) <= 0)
+           go->predictor_2 = 0;
+    }
 }
 
 /*
@@ -265,7 +295,10 @@ ccp_cilen(f)
 {
     ccp_options *go = &ccp_gotoptions[f->unit];
 
-    return (go->bsd_compress? CILEN_BSD_COMPRESS: 0);
+    return (go->bsd_compress? CILEN_BSD_COMPRESS: 0)
+       + (go->deflate? CILEN_DEFLATE: 0)
+       + (go->predictor_1? CILEN_PREDICTOR_1: 0)
+       + (go->predictor_2? CILEN_PREDICTOR_2: 0);
 }
 
 /*
@@ -277,18 +310,76 @@ ccp_addci(f, p, lenp)
     u_char *p;
     int *lenp;
 {
+    int res;
     ccp_options *go = &ccp_gotoptions[f->unit];
     u_char *p0 = p;
 
+    /*
+     * Add the compression types that we can receive, in decreasing
+     * preference order.  Get the kernel to allocate the first one
+     * in case it gets Acked.
+     */
+    if (go->deflate) {
+       p[0] = CI_DEFLATE;
+       p[1] = CILEN_DEFLATE;
+       p[2] = DEFLATE_MAKE_OPT(go->deflate_size);
+       p[3] = DEFLATE_CHK_SEQUENCE;
+       for (;;) {
+           res = ccp_test(f->unit, p, CILEN_DEFLATE, 0);
+           if (res > 0) {
+               p += CILEN_DEFLATE;
+               break;
+           }
+           if (res < 0 || go->deflate_size <= DEFLATE_MIN_SIZE) {
+               go->deflate = 0;
+               break;
+           }
+           --go->deflate_size;
+           p[2] = DEFLATE_MAKE_OPT(go->deflate_size);
+       }
+    }
     if (go->bsd_compress) {
        p[0] = CI_BSD_COMPRESS;
        p[1] = CILEN_BSD_COMPRESS;
        p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, go->bsd_bits);
-       if (ccp_test(f->unit, p, CILEN_BSD_COMPRESS, 0))
-           p += CILEN_BSD_COMPRESS;
-       else
-           go->bsd_compress = 0;
+       if (p != p0) {
+           p += CILEN_BSD_COMPRESS;    /* not the first option */
+       } else {
+           for (;;) {
+               res = ccp_test(f->unit, p, CILEN_BSD_COMPRESS, 0);
+               if (res > 0) {
+                   p += CILEN_BSD_COMPRESS;
+                   break;
+               }
+               if (res < 0 || go->bsd_bits <= BSD_MIN_BITS) {
+                   go->bsd_compress = 0;
+                   break;
+               }
+               --go->bsd_bits;
+               p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, go->bsd_bits);
+           }
+       }
+    }
+    /* XXX Should Predictor 2 be preferable to Predictor 1? */
+    if (go->predictor_1) {
+       p[0] = CI_PREDICTOR_1;
+       p[1] = CILEN_PREDICTOR_1;
+       if (p == p0 && ccp_test(f->unit, p, CILEN_PREDICTOR_1, 0) <= 0) {
+           go->predictor_1 = 0;
+       } else {
+           p += CILEN_PREDICTOR_1;
+       }
+    }
+    if (go->predictor_2) {
+       p[0] = CI_PREDICTOR_2;
+       p[1] = CILEN_PREDICTOR_2;
+       if (p == p0 && ccp_test(f->unit, p, CILEN_PREDICTOR_2, 0) <= 0) {
+           go->predictor_2 = 0;
+       } else {
+           p += CILEN_PREDICTOR_2;
+       }
     }
+
     *lenp = p - p0;
 }
 
@@ -303,7 +394,20 @@ ccp_ackci(f, p, len)
     int len;
 {
     ccp_options *go = &ccp_gotoptions[f->unit];
+    u_char *p0 = p;
 
+    if (go->deflate) {
+       if (len < CILEN_DEFLATE
+           || p[0] != CI_DEFLATE || p[1] != CILEN_DEFLATE
+           || p[2] != DEFLATE_MAKE_OPT(go->deflate_size)
+           || p[3] != DEFLATE_CHK_SEQUENCE)
+           return 0;
+       p += CILEN_DEFLATE;
+       len -= CILEN_DEFLATE;
+       /* XXX Cope with first/fast ack */
+       if (len == 0)
+           return 1;
+    }
     if (go->bsd_compress) {
        if (len < CILEN_BSD_COMPRESS
            || p[0] != CI_BSD_COMPRESS || p[1] != CILEN_BSD_COMPRESS
@@ -311,7 +415,27 @@ ccp_ackci(f, p, len)
            return 0;
        p += CILEN_BSD_COMPRESS;
        len -= CILEN_BSD_COMPRESS;
+       /* XXX Cope with first/fast ack */
+       if (p == p0 && len == 0)
+           return 1;
     }
+    if (go->predictor_1) {
+       if (len < CILEN_PREDICTOR_1
+           || p[0] != CI_PREDICTOR_1 || p[1] != CILEN_PREDICTOR_1)
+           return 0;
+       /* XXX Cope with first/fast ack */
+       if (p == p0 && len == 0)
+           return 1;
+    }
+    if (go->predictor_2) {
+       if (len < CILEN_PREDICTOR_2
+           || p[0] != CI_PREDICTOR_2 || p[1] != CILEN_PREDICTOR_2)
+           return 0;
+       /* XXX Cope with first/fast ack */
+       if (p == p0 && len == 0)
+           return 1;
+    }
+
     if (len != 0)
        return 0;
     return 1;
@@ -334,7 +458,24 @@ ccp_nakci(f, p, len)
     memset(&no, 0, sizeof(no));
     try = *go;
 
-    if (go->bsd_compress && !no.bsd_compress && len >= CILEN_BSD_COMPRESS
+    if (go->deflate && len >= CILEN_DEFLATE
+       && p[0] == CI_DEFLATE && p[1] == CILEN_DEFLATE) {
+       no.deflate = 1;
+       /*
+        * Peer wants us to use a different code size or something.
+        * Stop asking for Deflate if we don't understand his suggestion.
+        */
+       if (DEFLATE_METHOD(p[2]) != DEFLATE_METHOD_VAL
+           || DEFLATE_SIZE(p[2]) < DEFLATE_MIN_SIZE
+           || p[3] != DEFLATE_CHK_SEQUENCE)
+           try.deflate = 0;
+       else if (DEFLATE_SIZE(p[2]) < go->deflate_size)
+           go->deflate_size = DEFLATE_SIZE(p[2]);
+       p += CILEN_DEFLATE;
+       len -= CILEN_DEFLATE;
+    }
+
+    if (go->bsd_compress && len >= CILEN_BSD_COMPRESS
        && p[0] == CI_BSD_COMPRESS && p[1] == CILEN_BSD_COMPRESS) {
        no.bsd_compress = 1;
        /*
@@ -350,7 +491,9 @@ ccp_nakci(f, p, len)
     }
 
     /*
-     * Have a look at any remaining options...???
+     * Predictor-1 and 2 have no options, so they can't be Naked.
+     *
+     * XXX What should we do with any remaining options?
      */
 
     if (len != 0)
@@ -375,6 +518,22 @@ ccp_rejci(f, p, len)
 
     try = *go;
 
+    /*
+     * Cope with empty configure-rejects by ceasing to send
+     * configure-requests.
+     */
+    if (len == 0 && all_rejected[f->unit])
+       return -1;
+
+    if (go->deflate && len >= CILEN_DEFLATE
+       && p[0] == CI_DEFLATE && p[1] == CILEN_DEFLATE) {
+       if (p[2] != DEFLATE_MAKE_OPT(go->deflate_size)
+           || p[3] != DEFLATE_CHK_SEQUENCE)
+           return 0;           /* Rej is bad */
+       try.deflate = 0;
+       p += CILEN_DEFLATE;
+       len -= CILEN_DEFLATE;
+    }
     if (go->bsd_compress && len >= CILEN_BSD_COMPRESS
        && p[0] == CI_BSD_COMPRESS && p[1] == CILEN_BSD_COMPRESS) {
        if (p[2] != BSD_MAKE_OPT(BSD_CURRENT_VERSION, go->bsd_bits))
@@ -383,6 +542,18 @@ ccp_rejci(f, p, len)
        p += CILEN_BSD_COMPRESS;
        len -= CILEN_BSD_COMPRESS;
     }
+    if (go->predictor_1 && len >= CILEN_PREDICTOR_1
+       && p[0] == CI_PREDICTOR_1 && p[1] == CILEN_PREDICTOR_1) {
+       try.predictor_1 = 0;
+       p += CILEN_PREDICTOR_1;
+       len -= CILEN_PREDICTOR_1;
+    }
+    if (go->predictor_2 && len >= CILEN_PREDICTOR_2
+       && p[0] == CI_PREDICTOR_2 && p[1] == CILEN_PREDICTOR_2) {
+       try.predictor_2 = 0;
+       p += CILEN_PREDICTOR_2;
+       len -= CILEN_PREDICTOR_2;
+    }
 
     if (len != 0)
        return 0;
@@ -405,7 +576,7 @@ ccp_reqci(f, p, lenp, dont_nak)
     int *lenp;
     int dont_nak;
 {
-    int ret, newret;
+    int ret, newret, res;
     u_char *p0, *retp;
     int len, clen, type, nb;
     ccp_options *ho = &ccp_hisoptions[f->unit];
@@ -429,6 +600,52 @@ ccp_reqci(f, p, lenp, dont_nak)
            clen = p[1];
 
            switch (type) {
+           case CI_DEFLATE:
+               if (!ao->deflate || clen != CILEN_DEFLATE) {
+                   newret = CONFREJ;
+                   break;
+               }
+
+               ho->deflate = 1;
+               ho->deflate_size = nb = DEFLATE_SIZE(p[2]);
+               if (DEFLATE_METHOD(p[2]) != DEFLATE_METHOD_VAL
+                   || p[3] != DEFLATE_CHK_SEQUENCE
+                   || nb > ao->deflate_size) {
+                   newret = CONFNAK;
+                   nb = ao->deflate_size;
+               } else {
+                   /*
+                    * Check whether we can do Deflate with the window
+                    * size they want.  If the window is too big, reduce
+                    * it until the kernel can cope and nak with that.
+                    */
+                   for (;;) {
+                       if (nb < DEFLATE_MIN_SIZE) {
+                           newret = CONFREJ;
+                           p[2] = DEFLATE_MAKE_OPT(ho->deflate_size);
+                           break;
+                       }
+                       p[2] = DEFLATE_MAKE_OPT(nb);
+                       res = ccp_test(f->unit, p, CILEN_DEFLATE, 1);
+                       if (res != 0) {
+                           if (res < 0)
+                               newret = CONFREJ;
+                           break;
+                       }
+                       newret = CONFNAK;
+                       --nb;
+                   }
+               }
+               if (newret == CONFNAK && !dont_nak) {
+                   if (nb >= DEFLATE_MIN_SIZE) {
+                       p[2] = DEFLATE_MAKE_OPT(nb);
+                       p[3] = DEFLATE_CHK_SEQUENCE;
+                   } else {
+                       newret = CONFREJ;
+                   }
+               }
+               break;
+
            case CI_BSD_COMPRESS:
                if (!ao->bsd_compress || clen != CILEN_BSD_COMPRESS) {
                    newret = CONFREJ;
@@ -441,19 +658,61 @@ ccp_reqci(f, p, lenp, dont_nak)
                    || nb > ao->bsd_bits) {
                    newret = CONFNAK;
                    nb = ao->bsd_bits;
-               } else if (nb < BSD_MIN_BITS) {
-                   newret = CONFREJ;
-               } else if (!ccp_test(f->unit, p, CILEN_BSD_COMPRESS, 1)) {
-                   if (nb > BSD_MIN_BITS) {
-                       --nb;
+               } else {
+                   /*
+                    * Check whether we can do BSD_Compress with the code
+                    * size they want.  If the code size is too big, reduce
+                    * it until the kernel can cope and nak with that.
+                    */
+                   for (;;) {
+                       if (nb < BSD_MIN_BITS) {
+                           newret = CONFREJ;
+                           p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION,
+                                               ho->bsd_bits);
+                           break;
+                       }
+                       p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, nb);
+                       res = ccp_test(f->unit, p, CILEN_BSD_COMPRESS, 1);
+                       if (res != 0) {
+                           if (res < 0)
+                               newret = CONFREJ;
+                           break;
+                       }
                        newret = CONFNAK;
-                   } else
-                       newret = CONFREJ;
+                       --nb;
+                   }
                }
                if (newret == CONFNAK && !dont_nak) {
-                   p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, nb);
+                   if (nb >= BSD_MIN_BITS) {
+                       p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, nb);
+                   } else {
+                       newret = CONFREJ;
+                   }
                }
+               break;
 
+           case CI_PREDICTOR_1:
+               if (!ao->predictor_1 || clen != CILEN_PREDICTOR_1) {
+                   newret = CONFREJ;
+                   break;
+               }
+
+               ho->predictor_1 = 1;
+               if (ccp_test(f->unit, p, CILEN_PREDICTOR_1, 1) <= 0) {
+                   newret = CONFREJ;
+               }
+               break;
+
+           case CI_PREDICTOR_2:
+               if (!ao->predictor_2 || clen != CILEN_PREDICTOR_2) {
+                   newret = CONFREJ;
+                   break;
+               }
+
+               ho->predictor_2 = 1;
+               if (ccp_test(f->unit, p, CILEN_PREDICTOR_2, 1) <= 0) {
+                   newret = CONFREJ;
+               }
                break;
 
            default:
@@ -477,8 +736,12 @@ ccp_reqci(f, p, lenp, dont_nak)
        len -= clen;
     }
 
-    if (ret != CONFACK)
-       *lenp = retp - p0;
+    if (ret != CONFACK) {
+       if (ret == CONFREJ && *lenp == retp - p0)
+           all_rejected[f->unit] = 1;
+       else
+           *lenp = retp - p0;
+    }
     return ret;
 }
 
@@ -493,9 +756,9 @@ ccp_up(f)
     ccp_options *ho = &ccp_hisoptions[f->unit];
 
     ccp_flags_set(f->unit, 1, 1);
-    if (go->bsd_compress || ho->bsd_compress)
+    if (ANY_COMPRESS(*go) || ANY_COMPRESS(*ho))
        syslog(LOG_NOTICE, "%s enabled",
-              go->bsd_compress? ho->bsd_compress? "Compression":
+              ANY_COMPRESS(*go)? ANY_COMPRESS(*ho)? "Compression":
               "Receive compression": "Transmit compression");
 }
 
@@ -566,6 +829,16 @@ ccp_printpkt(p, plen, printer, arg)
            len -= optlen;
            optend = p + optlen;
            switch (code) {
+           case CI_DEFLATE:
+               if (optlen >= CILEN_DEFLATE) {
+                   printer(arg, "deflate %d", DEFLATE_SIZE(p[2]));
+                   if (DEFLATE_METHOD(p[2]) != DEFLATE_METHOD_VAL)
+                       printer(arg, " method %d", DEFLATE_METHOD(p[2]));
+                   if (p[3] != DEFLATE_CHK_SEQUENCE)
+                       printer(arg, " check %d", p[3]);
+                   p += CILEN_DEFLATE;
+               }
+               break;
            case CI_BSD_COMPRESS:
                if (optlen >= CILEN_BSD_COMPRESS) {
                    printer(arg, "bsd v%d %d", BSD_VERSION(p[2]),
@@ -573,6 +846,18 @@ ccp_printpkt(p, plen, printer, arg)
                    p += CILEN_BSD_COMPRESS;
                }
                break;
+           case CI_PREDICTOR_1:
+               if (optlen >= CILEN_PREDICTOR_1) {
+                   printer(arg, "predictor 1");
+                   p += CILEN_PREDICTOR_1;
+               }
+               break;
+           case CI_PREDICTOR_2:
+               if (optlen >= CILEN_PREDICTOR_2) {
+                   printer(arg, "predictor 2");
+                   p += CILEN_PREDICTOR_2;
+               }
+               break;
            }
            while (p < optend)
                printer(arg, " %.2x", *p++);