Add an error check for correct formatting in Deflate uncompressed

[sgt/halibut] / deflate.c

diff --git a/deflate.c b/deflate.c
index 33c70cc..a04f86d 100644 (file)
--- a/deflate.c
+++ b/deflate.c
@@ -95,7 +95,7 @@
 #define debug_int(x...) ( fprintf(stderr, x) )
 #define debug(x) ( debug_int x )
 #else
-#define debug(x)
+#define debug(x) ((void)0)
 #endif
 
 #ifdef STANDALONE
@@ -651,8 +651,8 @@ struct deflate_compress_ctx {
     unsigned long datasize;
     int lastblock;
     int finished;
-    unsigned char static_len1[286], static_len2[30];
-    int static_code1[286], static_code2[30];
+    unsigned char static_len1[288], static_len2[30];
+    int static_code1[288], static_code2[30];
     struct huftrees sht;
 #ifdef STATISTICS
     unsigned long bitcount;
@@ -912,7 +912,8 @@ static void deflate_buildhuf(int *freqs, unsigned char *lengths,
      * assert()-level confident that the resulting code lengths
      * contain nothing outside the permitted range.
      */
-    maxprob = (limit == 16 ? 2584 : 55);   /* no point in computing full F_n */
+    assert(limit == 15 || limit == 7);
+    maxprob = (limit == 15 ? 2584 : 55);   /* no point in computing full F_n */
     totalfreq = nactivesyms = 0;
     smallestfreq = -1;
     for (i = 0; i < nsyms; i++) {
@@ -1575,11 +1576,11 @@ deflate_compress_ctx *deflate_compress_new(int type)
     {
        int i;
 
-       for (i = 0; i < lenof(out->static_len1); i++)
+       for (i = 0; i < (int)lenof(out->static_len1); i++)
            out->static_len1[i] = (i < 144 ? 8 :
                                   i < 256 ? 9 :
                                   i < 280 ? 7 : 8);
-       for (i = 0; i < lenof(out->static_len2); i++)
+       for (i = 0; i < (int)lenof(out->static_len2); i++)
            out->static_len2[i] = 5;
     }
     hufcodes(out->static_len1, out->static_code1, lenof(out->static_code1));
@@ -2040,7 +2041,8 @@ int deflate_decompress_data(deflate_decompress_ctx *dctx,
 {
     const coderecord *rec;
     const unsigned char *block = (const unsigned char *)vblock;
-    int code, bfinal, btype, rep, dist, nlen, header, cksum;
+    int code, bfinal, btype, rep, dist, nlen, header;
+    unsigned long cksum;
     int error = 0;
 
     if (len == 0) {
@@ -2439,8 +2441,12 @@ int deflate_decompress_data(deflate_decompress_ctx *dctx,
             */
            if (dctx->nbits < 16)
                goto finished;
-           nlen = dctx->bits & 0xFFFF;
+           nlen = 0xFFFF & ~dctx->bits;
            EATBITS(16);
+           if (dctx->uncomplen != (nlen ^ 0xFFFF)) {
+                error = DEFLATE_ERR_UNCOMP_HDR;
+                goto finished;
+            }
            if (dctx->uncomplen == 0)
                dctx->state = OUTSIDEBLK;       /* block is empty */
            else