X-Git-Url: http://git.ozlabs.org/?p=ppp.git;a=blobdiff_plain;f=modules%2Fdeflate.c;h=67c6c16b71ea35dd6cc918693f2f3ab95237b59d;hp=c285b47fd7b5d13a14c8305fe9767c6a09a43caa;hb=2b18ef2f6444c3d18a511de6248f0dbe76cd5356;hpb=a51ffdeea95fdbbb21555408d3e5002ad7069c8a

diff --git a/modules/deflate.c b/modules/deflate.c
index c285b47..67c6c16 100644
--- a/modules/deflate.c
+++ b/modules/deflate.c
@@ -27,7 +27,7 @@
  * OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS,
  * OR MODIFICATIONS.
  *
- * $Id: deflate.c,v 1.3 1996/06/26 00:53:16 paulus Exp $
+ * $Id: deflate.c,v 1.6 1997/11/27 06:05:17 paulus Exp $
  */
 
 #ifdef AIX4
@@ -50,6 +50,8 @@
 
 #if DO_DEFLATE
 
+#define DEFLATE_DEBUG	1
+
 /*
  * State for a Deflate (de)compressor.
  */
@@ -67,7 +69,8 @@ struct deflate_state {
 #define DEFLATE_OVHD	2		/* Deflate overhead/packet */
 
 static void	*z_alloc __P((void *, u_int items, u_int size));
-static void	z_free __P((void *, void *ptr, u_int nb));
+static void	*z_alloc_init __P((void *, u_int items, u_int size));
+static void	z_free __P((void *, void *ptr));
 static void	*z_comp_alloc __P((u_char *options, int opt_len));
 static void	*z_decomp_alloc __P((u_char *options, int opt_len));
 static void	z_comp_free __P((void *state));
@@ -110,25 +113,58 @@ struct compressor ppp_deflate = {
 /*
  * Space allocation and freeing routines for use by zlib routines.
  */
+struct zchunk {
+    u_int	size;
+    u_int	guard;
+};
+
+#define GUARD_MAGIC	0x77a6011a
+
 static void *
-z_alloc(notused, items, size)
+z_alloc_init(notused, items, size)
     void *notused;
     u_int items, size;
 {
+    struct zchunk *z;
+
+    size = items * size + sizeof(struct zchunk);
 #ifdef __osf__
-    return ALLOC_SLEEP(items * size);
+    z = (struct zchunk *) ALLOC_SLEEP(size);
 #else
-    return ALLOC_NOSLEEP(items * size);
+    z = (struct zchunk *) ALLOC_NOSLEEP(size);
 #endif
+    z->size = size;
+    z->guard = GUARD_MAGIC;
+    return (void *) (z + 1);
+}
+
+static void *
+z_alloc(notused, items, size)
+    void *notused;
+    u_int items, size;
+{
+    struct zchunk *z;
+
+    size = items * size + sizeof(struct zchunk);
+    z = (struct zchunk *) ALLOC_NOSLEEP(size);
+    z->size = size;
+    z->guard = GUARD_MAGIC;
+    return (void *) (z + 1);
 }
 
 static void
-z_free(notused, ptr, nbytes)
+z_free(notused, ptr)
     void *notused;
     void *ptr;
-    u_int nbytes;
 {
-    FREE(ptr, nbytes);
+    struct zchunk *z = ((struct zchunk *) ptr) - 1;
+
+    if (z->guard != GUARD_MAGIC) {
+	printf("ppp: z_free of corrupted chunk at %x (%x, %x)\n",
+	       z, z->size, z->guard);
+	return;
+    }
+    FREE(z, z->size);
 }
 
 /*
@@ -151,19 +187,26 @@ z_comp_alloc(options, opt_len)
     if (w_size < DEFLATE_MIN_SIZE || w_size > DEFLATE_MAX_SIZE)
 	return NULL;
 
+
+#ifdef __osf__
+    state = (struct deflate_state *) ALLOC_SLEEP(sizeof(*state));
+#else
     state = (struct deflate_state *) ALLOC_NOSLEEP(sizeof(*state));
+#endif
+
     if (state == NULL)
 	return NULL;
 
     state->strm.next_in = NULL;
-    state->strm.zalloc = (alloc_func) z_alloc;
+    state->strm.zalloc = (alloc_func) z_alloc_init;
     state->strm.zfree = (free_func) z_free;
     if (deflateInit2(&state->strm, Z_DEFAULT_COMPRESSION, DEFLATE_METHOD_VAL,
-		     -w_size, 8, Z_DEFAULT_STRATEGY, DEFLATE_OVHD+2) != Z_OK) {
+		     -w_size, 8, Z_DEFAULT_STRATEGY) != Z_OK) {
 	FREE(state, sizeof(*state));
 	return NULL;
     }
 
+    state->strm.zalloc = (alloc_func) z_alloc;
     state->w_size = w_size;
     bzero(&state->stats, sizeof(state->stats));
     return (void *) state;
@@ -322,11 +365,8 @@ z_compress(arg, mret, mp, orig_len, maxolen)
 
     /*
      * See if we managed to reduce the size of the packet.
-     * If the compressor just gave us a single zero byte, it means
-     * the packet was incompressible.
      */
-    if (olen < orig_len && m != NULL
-	&& !(olen == PPP_HDRLEN + 3 && *wptr == 0)) {
+    if (olen < orig_len && m != NULL) {
 	state->stats.comp_bytes += olen;
 	state->stats.comp_packets++;
     } else {
@@ -383,18 +423,23 @@ z_decomp_alloc(options, opt_len)
     if (w_size < DEFLATE_MIN_SIZE || w_size > DEFLATE_MAX_SIZE)
 	return NULL;
 
+#ifdef __osf__
+    state = (struct deflate_state *) ALLOC_SLEEP(sizeof(*state));
+#else
     state = (struct deflate_state *) ALLOC_NOSLEEP(sizeof(*state));
+#endif
     if (state == NULL)
 	return NULL;
 
     state->strm.next_out = NULL;
-    state->strm.zalloc = (alloc_func) z_alloc;
+    state->strm.zalloc = (alloc_func) z_alloc_init;
     state->strm.zfree = (free_func) z_free;
     if (inflateInit2(&state->strm, -w_size) != Z_OK) {
 	FREE(state, sizeof(*state));
 	return NULL;
     }
 
+    state->strm.zalloc = (alloc_func) z_alloc;
     state->w_size = w_size;
     bzero(&state->stats, sizeof(state->stats));
     return (void *) state;
@@ -489,7 +534,9 @@ z_decompress(arg, mi, mop)
     /* Check the sequence number. */
     seq = (hdr[PPP_HDRLEN] << 8) + hdr[PPP_HDRLEN+1];
     if (seq != state->seqno) {
+#if !DEFLATE_DEBUG
 	if (state->debug)
+#endif
 	    printf("z_decompress%d: bad seq # %d, expected %d\n",
 		   state->unit, seq, state->seqno);
 	return DECOMP_ERROR;
@@ -535,7 +582,9 @@ z_decompress(arg, mi, mop)
     for (;;) {
 	r = inflate(&state->strm, flush);
 	if (r != Z_OK) {
+#if !DEFLATE_DEBUG
 	    if (state->debug)
+#endif
 		printf("z_decompress%d: inflate returned %d (%s)\n",
 		       state->unit, r, (state->strm.msg? state->strm.msg: ""));
 	    freemsg(mo_head);
@@ -583,6 +632,12 @@ z_decompress(arg, mi, mop)
     mo->b_wptr += ospace - state->strm.avail_out;
     olen += ospace - state->strm.avail_out;
 
+#if DEFLATE_DEBUG
+    if (olen > state->mru + PPP_HDRLEN)
+	printf("ppp_deflate%d: exceeded mru (%d > %d)\n",
+	       state->unit, olen, state->mru + PPP_HDRLEN);
+#endif
+
     state->stats.unc_bytes += olen;
     state->stats.unc_packets++;
     state->stats.comp_bytes += rlen;
@@ -636,10 +691,11 @@ z_incomp(arg, mi)
 	r = inflateIncomp(&state->strm);
 	if (r != Z_OK) {
 	    /* gak! */
-	    if (state->debug) {
+#if !DEFLATE_DEBUG
+	    if (state->debug)
+#endif
 		printf("z_incomp%d: inflateIncomp returned %d (%s)\n",
 		       state->unit, r, (state->strm.msg? state->strm.msg: ""));
-	    }
 	    return;
 	}
 	mi = mi->b_cont;