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Comment:Rename the "security.html" document as "Defense Against Dark Arts". Add the additional recommendation to avoid memory-mapped I/O on untrusted database files.
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SHA3-256: 11d0259504e7ca5f7bc589e472757897467f23b0722931b810be9859dbf3ae38
User & Date: drh 2018-12-14 15:54:05.478
Context
2018-12-15
01:17
Merge defense-against-dark-arts fixes from trunk. (check-in: a8707b40a7 user: drh tags: branch-3.26)
2018-12-14
19:01
Fix typos in the defense-against-dark-arts document. (check-in: 94ad3e51e7 user: drh tags: trunk)
15:54
Rename the "security.html" document as "Defense Against Dark Arts". Add the additional recommendation to avoid memory-mapped I/O on untrusted database files. (check-in: 11d0259504 user: drh tags: trunk)
2018-12-10
12:52
Futher homepage enhancements. Improvements and typo fixes on secondary pages. (check-in: e6aa1d2d9a user: drh tags: trunk)
Changes
Unified Diff Ignore Whitespace Patch
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<title>Resistance To Attack</title>
<tcl>hd_keywords security {attack resistance}</tcl>

<fancy_format>

<h1>SQLite Always Validates Its Inputs</h1>

<p>
SQLite should never crash, overflow a buffer, leak memory,
or exhibit any other harmful behavior, even with presented with
maliciously malformed SQL inputs or database files.  SQLite should
always detected erroneous inputs and raise an error, not crash or
corrupt memory.
Any malfunction caused by an SQL input or database file
is considered a serious bug and will be promptly addressed when
brought to the attention of the SQLite developers.  SQLite is
extensively fuzz-tested to help ensure that it is highly resistant
to these kinds of errors.

<p>
Nevertheless, bugs happen.
If you are writing an application that sends untrusted SQL inputs
or database files to SQLite, there are additional steps you can take

to help prevent zero-day exploits caused by undetected bugs:

<h2>Untrusted SQL Inputs</h2>
<p>
Applications that accept untrusted SQL inputs should take the following
precautions:

<ol>

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<title>Defense Against Dark Arts</title>
<tcl>hd_keywords security {attack resistance} \
  {defense against dark arts}</tcl>
<fancy_format>

<h1>SQLite Always Validates Its Inputs</h1>

<p>
SQLite should never crash, overflow a buffer, leak memory,
or exhibit any other harmful behavior, even with presented with
maliciously malformed SQL inputs or database files.  SQLite should
always detected erroneous inputs and raise an error, not crash or
corrupt memory.
Any malfunction caused by an SQL input or database file
is considered a serious bug and will be promptly addressed when
brought to the attention of the SQLite developers.  SQLite is
extensively fuzz-tested to help ensure that it is resistant
to these kinds of errors.

<p>
Nevertheless, bugs happen.
If you are writing an application that sends untrusted SQL inputs
or database files to SQLite, there are additional steps you can take
to help reduce the attack surface and
prevent zero-day exploits caused by undetected bugs.

<h2>Untrusted SQL Inputs</h2>
<p>
Applications that accept untrusted SQL inputs should take the following
precautions:

<ol>
︙︙
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<h2>Untrusted SQLite Database Files</h2>

<p>Applications that accept untrusted database files should do the following:

<ol>
<li value="3"><p>
Run [PRAGMA integrity_check] or [PRAGMA quick_check] on the database

first, prior to running any other SQLite, and reject the file if any
errors are detected.

<li><p>
Enable the [PRAGMA cell_size_check=ON] setting.




</ol>

<h1>Summary</h1>

<p>
The precautions above are not required in order to use SQLite safely
with potentially hostile inputs.
However, they do provide an extra layer of defense against zero-day
exploits and are encouraged for applications that pass data from
untrusted sources into SQLite.








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<h2>Untrusted SQLite Database Files</h2>

<p>Applications that accept untrusted database files should do the following:

<ol>
<li value="3"><p>
Run [PRAGMA integrity_check] or [PRAGMA quick_check] on the database
as first SQL statement after opening the database files and
prior to running any other SQL statements.  Reject and refuse to
process any database file containing errors.

<li><p>
Enable the [PRAGMA cell_size_check=ON] setting.

<li><p>
Do not enable memory-mapped I/O.
In other words, make sure that [PRAGMA mmap_size=0].
</ol>

<h1>Summary</h1>

<p>
The precautions above are not required in order to use SQLite safely
with potentially hostile inputs.
However, they do provide an extra layer of defense against zero-day
exploits and are encouraged for applications that pass data from
untrusted sources into SQLite.