diff --git a/httpd.h b/httpd.h
index d607860..36f2a1b 100644
--- a/httpd.h
+++ b/httpd.h
@@ -192,7 +192,7 @@ static void inline close_on_exec(int fd)
 #ifdef USE_SSL
 extern int ssl_read(struct REQUEST *req, char *buf, int len);
 extern int ssl_write(struct REQUEST *req, char *buf, int len);
-extern int ssl_blk_write(struct REQUEST *req, int offset, int len);
+extern int ssl_blk_write(struct REQUEST *req, off_t offset, size_t len);
 extern void init_ssl(void);
 extern void open_ssl_session(struct REQUEST *req);
 #endif
diff --git a/ssl.c b/ssl.c
index 830f955..9c4e2fb 100644
--- a/ssl.c
+++ b/ssl.c
@@ -64,11 +64,16 @@ int ssl_write(struct REQUEST *req, char *buf, int len)
     return rc;
 }
 
-int ssl_blk_write(struct REQUEST *req, int offset, int len)
+int ssl_blk_write(struct REQUEST *req, off_t offset, size_t len)
 {
     int  rc;
     char buf[4096];
 
+    if (lseek(req->bfd, offset, SEEK_SET) == -1) {
+        if (debug) perror("lseek");
+        return -1;
+    }
+
     if (len > sizeof(buf))
 	len = sizeof(buf);
     rc = read(req->bfd, buf, len);