1 files changed, 124 insertions, 0 deletions
diff --git a/erts/etc/unix/safe_string.c b/erts/etc/unix/safe_string.c
new file mode 100644
index 0000000000..666022dc61
--- /dev/null
+++ b/erts/etc/unix/safe_string.c
@@ -0,0 +1,124 @@
+/*
+ * %CopyrightBegin%
+ * 
+ * Copyright Ericsson AB 2008-2016. All Rights Reserved.
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 
+ * %CopyrightEnd%
+ */
+/* 
+ * Module: safe_string.c
+ * 
+ * This is a bunch of generic string operation
+ * that are safe regarding buffer overflow.
+ *
+ * All string functions terminate the process with an error message
+ * on buffer overflow.
+ */
+
+#ifdef HAVE_CONFIG_H
+#  include "config.h"
+#endif
+#include "safe_string.h"
+#include <stdio.h>
+#include <string.h>
+#include <stdarg.h>
+#include <stdlib.h>
+
+
+static void string_overflow_handler(const char* format, ...)
+{
+    va_list args;
+    va_start(args, format);
+    vfprintf(stderr,format,args);
+    va_end(args);
+    exit(1);
+}
+
+int vsn_printf(char* dst, size_t size, const char* format, va_list args)
+{
+    int ret = vsnprintf(dst, size, format, args);
+    if (ret >= size || ret < 0) {
+	string_overflow_handler("Buffer truncated '%s'\n",dst);
+    }
+    return ret;
+}
+
+int sn_printf(char* dst, size_t size, const char* format, ...)
+{
+    va_list args;
+    int ret;
+    va_start(args, format);
+    ret = vsn_printf(dst,size,format,args);
+    va_end(args);
+    return ret;
+}
+
+int strn_cpy(char* dst, size_t size, const char* src)
+{
+    return sn_printf(dst,size,"%s",src);
+}
+
+int strn_cat(char* dst, size_t size, const char* src)
+{
+    return strn_catf(dst,size,"%s",src);
+}
+
+int strn_catf(char* dst, size_t size, const char* format, ...)
+{
+    int ret;
+    va_list args;
+#ifdef _GNU_SOURCE
+    int len = strnlen(dst,size);
+#else
+    int len = strlen(dst);
+#endif
+
+    if (len >= size) {
+	string_overflow_handler("Buffer already overflowed '%.*s'\n",
+				size, dst);
+    }
+    va_start(args, format);
+    ret = vsn_printf(dst+len, size-len, format, args);
+    va_end(args);
+    return len+ret;
+}
+
+char* find_str(const char* haystack, int hsize, const char* needle)
+{
+    int i = 0;
+    int nsize = strlen(needle);
+    hsize -= nsize - 1;
+    for (i=0; i<hsize; i++) {
+	if (haystack[i]==needle[0] && strncmp(haystack+i,needle,nsize)==0) {
+	    return (char*)(haystack+i);
+	}
+    }
+    return NULL;
+}
+
+#ifndef HAVE_MEMMOVE
+void* memmove(void *dest, const void *src, size_t n)
+{
+    int i;
+    if (src > dest) {
+	for (i=0; i<n; i++) ((char*)dest)[i] = ((char*)src)[i];
+    }
+    else {
+	for (i=(int)(n-1); i>=0; i--) ((char*)dest)[i] = ((char*)src)[i];
+    }
+    return dest;
+}
+#endif /* HAVE_MEMMOVE */
+