155 lines
2.5 KiB
HTML
155 lines
2.5 KiB
HTML
<HTML
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><HEAD
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><TITLE
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>File Contents</TITLE
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><META
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NAME="GENERATOR"
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CONTENT="Modular DocBook HTML Stylesheet Version 1.7"><LINK
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REL="HOME"
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TITLE="Secure Programming for Linux and Unix HOWTO"
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HREF="index.html"><LINK
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REL="UP"
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TITLE="Validate All Input"
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HREF="input.html"><LINK
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REL="PREVIOUS"
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TITLE="File Names"
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HREF="file-names.html"><LINK
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REL="NEXT"
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TITLE="Web-Based Application Inputs (Especially CGI Scripts)"
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HREF="web-apps.html"></HEAD
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><BODY
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CLASS="SECT1"
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BGCOLOR="#FFFFFF"
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><TR
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COLSPAN="3"
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ALIGN="center"
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>Secure Programming for Linux and Unix HOWTO</TH
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></TR
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><TR
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><TD
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WIDTH="10%"
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ALIGN="left"
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VALIGN="bottom"
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><A
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HREF="file-names.html"
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ACCESSKEY="P"
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>Prev</A
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></TD
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><TD
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WIDTH="80%"
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ALIGN="center"
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VALIGN="bottom"
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>Chapter 5. Validate All Input</TD
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><TD
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WIDTH="10%"
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ALIGN="right"
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VALIGN="bottom"
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><A
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HREF="web-apps.html"
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ACCESSKEY="N"
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>Next</A
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></TD
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ALIGN="LEFT"
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WIDTH="100%"></DIV
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><DIV
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CLASS="SECT1"
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><H1
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CLASS="SECT1"
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><A
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NAME="FILE-CONTENTS"
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></A
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>5.5. File Contents</H1
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><P
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>If a program takes directions from a file, it must not trust that file
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specially unless only a trusted user can control its contents.
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Usually this means that an untrusted user must not be able to modify the file,
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its directory, or any of its ancestor directories.
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Otherwise, the file must be treated as suspect.</P
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><P
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>If the directions in the file are supposed to be from an untrusted user,
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then make sure that the inputs from the file are protected as describe
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throughout this book.
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In particular, check that values match the set of legal values, and that
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buffers are not overflowed.</P
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></DIV
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><DIV
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WIDTH="33%"
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ALIGN="left"
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VALIGN="top"
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><A
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HREF="file-names.html"
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ACCESSKEY="P"
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>Prev</A
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HREF="index.html"
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>Home</A
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VALIGN="top"
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HREF="web-apps.html"
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ACCESSKEY="N"
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>Next</A
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></TD
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></TR
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><TR
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><TD
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WIDTH="33%"
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ALIGN="left"
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VALIGN="top"
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>File Names</TD
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><TD
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WIDTH="34%"
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ALIGN="center"
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VALIGN="top"
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HREF="input.html"
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>Up</A
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></TD
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><TD
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WIDTH="33%"
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ALIGN="right"
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VALIGN="top"
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>Web-Based Application Inputs (Especially CGI Scripts)</TD
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></TR
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></TABLE
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></DIV
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></BODY
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></HTML
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> |