From 823fc8bbe01c8e5d3fbe1f02bd4a7c45994326c1 Mon Sep 17 00:00:00 2001
From: "git@daemon.de" <git@daemon.de>
Date: Thu, 13 Feb 2014 15:30:23 +0100
Subject: [PATCH] added check if input is not binary

---
 include/pcp/z85.h |  4 ++++
 libpcp/z85.c      | 24 ++++++++++++++++++++++++
 2 files changed, 28 insertions(+)

diff --git a/include/pcp/z85.h b/include/pcp/z85.h
index 73d69a2..f3d514b 100644
--- a/include/pcp/z85.h
+++ b/include/pcp/z85.h
@@ -23,6 +23,8 @@
 /*  from https://github.com/tlinden/curve-keygen/ */
 #ifndef _HAVE_PCP_Z85_H
 
+#include <ctype.h>
+
 #include "defines.h"
 #include "zmq_z85.h"
 #include "mem.h"
@@ -44,4 +46,6 @@ char *pcp_z85_encode(unsigned char *raw, size_t srclen, size_t *dstlen);
 char *pcp_readz85file(FILE *infile);
 char *pcp_readz85string(unsigned char *input, size_t bufsize);
 
+size_t _buffer_is_binary(unsigned char *buf, size_t len);
+
 #endif /*  _HAVE_PCP_Z85_H */
diff --git a/libpcp/z85.c b/libpcp/z85.c
index 3713dd7..55e351c 100644
--- a/libpcp/z85.c
+++ b/libpcp/z85.c
@@ -22,6 +22,20 @@
 
 #include "z85.h"
 
+size_t _buffer_is_binary(unsigned char *buf, size_t len) {
+  size_t pos;
+  for (pos=0; pos<len; ++pos) {
+    if(buf[pos] == '\0' || (buf[pos] != '\r' && buf[pos] != '\n' && isprint(buf[pos]) == 0)) {
+      break;
+    }
+  }
+  if(pos < len)
+    return pos;
+  else
+    return 0;
+}
+
+
 unsigned char *pcp_padfour(unsigned char *src, size_t srclen, size_t *dstlen) {
   size_t outlen, zerolen;
   unsigned char *dst;
@@ -145,6 +159,16 @@ char *pcp_readz85string(unsigned char *input, size_t bufsize) {
   int i;
   size_t MAXLINE = 1024;
 
+  if(bufsize == 0) {
+    fatal("Input file is empty!\n");
+    return NULL;
+  }
+
+  if(_buffer_is_binary(input, bufsize) > 0) {
+    fatal("input is not z85 encoded and contains pure binary data");
+    return NULL;
+  }
+
   Buffer *z = buffer_new(MAXLINE, "z");
   Buffer *line = buffer_new(MAXLINE, "line");
   char *oneline;