Zip64 support is broken

Problem description:

Trying to write a large (>4Gb) zip-ed image results to immediate error:

The error is confusing, since the .zip file is certainly not encrypted.

Steps to reproduce:

1. On a Ubuntu Linux machine create an image file larger than 4 Gb:

dd if=/dev/zero of=1.img bs=1M count=5K

2. Compress with zip:

zip 1.img.zip 1.img

3. Open 1.img.zip file in UsbImager and try to write it.

Root cause:

I believe the error is because of the wrong buffer bounds calculation while parsing zip64 extra header in stream_open(), src/stream.c: sizeof(ctx->compBuf) evaluates to unsigned char * pointer size (8 bytes), and not the actual buffer size.

Same problem for Zstd parsing.

Please consider to apply the following patch:

diff --git a/src/stream.c b/src/stream.c
index 1f1930c..e47ba08 100644
--- a/src/stream.c
+++ b/src/stream.c
@@ -489,7 +489,7 @@ int stream_open(stream_t *ctx, char *fn, int uncompr)
         if(verbose) printf(" zstd\r\n");
         ctx->compSize = fs;
         ctx->cmrdSize = hs;
-        zr = (uint64_t)ZSTD_getFrameContentSize(ctx->compBuf, sizeof(ctx->compBuf));
+        zr = (uint64_t)ZSTD_getFrameContentSize(ctx->compBuf, buffer_size);
         if(zr != ZSTD_CONTENTSIZE_UNKNOWN && zr != ZSTD_CONTENTSIZE_ERROR)
             ctx->fileSize = zr;
         else
@@ -557,7 +557,7 @@ int stream_open(stream_t *ctx, char *fn, int uncompr)
             /* zip64 */
             if(verbose) printf("   zip64\r\n");
             for(x = 30 + ctx->compBuf[26] + (ctx->compBuf[27]<<8), y = x + ctx->compBuf[28] + (ctx->compBuf[29]<<8);
-                x < y && x < (int)sizeof(ctx->compBuf) - 4; x += 4 + ctx->compBuf[x + 2] + (ctx->compBuf[x + 3]<<8))
+                x < y && x < buffer_size - 4; x += 4 + ctx->compBuf[x + 2] + (ctx->compBuf[x + 3]<<8))
                     if(ctx->compBuf[x] == 1 && ctx->compBuf[x + 1] == 0) {
                         memcpy(&ctx->compSize, ctx->compBuf + x + 12, 8);
                         memcpy(&ctx->fileSize, ctx->compBuf + x + 4, 8);