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commit: f756acec0e3a45939cc506f996bb2bfd71c0bfa4 |
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Author: klondike <klondike <AT> xiscosoft <DOT> es> |
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AuthorDate: Sat Apr 28 19:22:04 2012 +0000 |
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Commit: Francisco Blas Izquierdo Riera <klondike <AT> xiscosoft <DOT> es> |
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CommitDate: Sat Apr 28 19:22:04 2012 +0000 |
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URL: http://git.overlays.gentoo.org/gitweb/?p=proj/hardened-docs.git;a=commit;h=f756acec |
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|
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Fix bug #413289 |
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|
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--- |
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xml/hardened-debugging.xml | 12 +- |
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xml/revdep-pax.xml | 616 +++----------------------------------------- |
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2 files changed, 43 insertions(+), 585 deletions(-) |
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|
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diff --git a/xml/hardened-debugging.xml b/xml/hardened-debugging.xml |
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index 21a0fc9..0a648a9 100644 |
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--- a/xml/hardened-debugging.xml |
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+++ b/xml/hardened-debugging.xml |
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@@ -5,7 +5,7 @@ |
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<guide link="/proj/en/hardened/hardenedfaq.xml" lang="en"> |
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<title>Gentoo Hardened debugging</title> |
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<author title="Author"> |
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- <mail link="klondike@×××××××××.es">klondike</mail> |
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+ <mail link="klondike"/> |
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</author> |
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<author title="Contributor"> |
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<!-- Via bugs #341889 and 265693 --> |
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@@ -21,8 +21,8 @@ hardened kernel and toolcahin with PaX/Grsec, PIE and SSP. |
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<!-- See http://creativecommons.org/licenses/by-sa/2.5 --> |
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<license/> |
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|
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-<version>1.0</version> |
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-<date>2010-10-26</date> |
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+<version>2</version> |
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+<date>2012-04-28</date> |
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|
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<chapter> |
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<title>Solving the '??' issue.</title> |
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@@ -214,10 +214,12 @@ available breakpoints. |
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<p> |
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After debugging you may want to restore the system to its normal state, if you |
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used <c>paxctl</c> you can reset the flags to default using the <c>-z</c> flag. |
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+Since the -z flags will zero all the flags also want to keep trampoline |
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+emulation disabled. This is done with the <c>-e</c> flag. |
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</p> |
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|
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-<pre caption="Reseting the flags back to its defaults."> |
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-# <i>paxctl -z binary</i> |
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+<pre caption="Reseting the flags back to its defaults. Keep trampoline emulation disabled"> |
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+# <i>paxctl -ze binary</i> |
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</pre> |
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|
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</body> |
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|
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diff --git a/xml/revdep-pax.xml b/xml/revdep-pax.xml |
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index ba9f822..cbf3181 100644 |
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--- a/xml/revdep-pax.xml |
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+++ b/xml/revdep-pax.xml |
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@@ -23,7 +23,10 @@ requiring RWX memory in order to process JIT code. |
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<date>2012-02-19</date> |
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|
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<chapter> |
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-<title>What's <c>revdep-pax</c> about?</title> |
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+<title>What's revdep-pax about?</title> |
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+ |
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+<section> |
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+<body> |
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|
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<p by="Geroge Orwell"> |
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Since the early days of PaX it was known that all programs were equal although |
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@@ -33,6 +36,9 @@ allowing system administrators and users telling the system which binaries |
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needed this lessened environment the PaX marks were created. |
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</p> |
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|
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+</body> |
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+</section> |
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+ |
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<section> |
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<title>A quick introduction to PaX markings.</title> |
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<body> |
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@@ -106,7 +112,7 @@ called. In order to solve this issue we have created <c>revdep-pax</c>. |
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</body> |
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</section> |
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<section> |
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-<title>What's <c>revdep-pax</c>?</title> |
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+<title>What's revdep-pax?</title> |
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<body> |
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|
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<p> |
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@@ -134,7 +140,10 @@ libraries linked by an object and backwards to the objects linked by a library. |
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</chapter> |
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|
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<chapter> |
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-<title>Using <c>revdep-pax</c></title> |
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+<title>Using revdep-pax</title> |
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+ |
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+<section> |
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+<body> |
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|
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<p by="The Emperor"> |
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In order to witness the firepower of this fully ARMED and OPERATIONAL tool |
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@@ -142,6 +151,9 @@ you'll first need to learn how to use it, once you are done, you'll be |
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able to fire at will. |
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</p> |
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|
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+</body> |
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+</section> |
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+ |
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<section> |
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<title>Propagating PaX marks backwards from a library to objects that link at it |
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</title> |
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@@ -149,592 +161,36 @@ able to fire at will. |
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|
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<p> |
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This is going to be probably the main way in which you are going to use this |
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-utility. What it does is check all the libraries linked statically |
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-The <c>scanelf</c> application is part of the <c>app-misc/pax-utils</c> package. |
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-With this application you can print out information specific to the ELF |
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-structure of a binary. The following table sums up the various options. |
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-</p> |
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- |
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-<table> |
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-<tr> |
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- <th>Option</th> |
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- <th>Long Option</th> |
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- <th>Description</th> |
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-</tr> |
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-<tr> |
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- <ti>-p</ti> |
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- <ti>--path</ti> |
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- <ti>Scan all directories in PATH environment</ti> |
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-</tr> |
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-<tr> |
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- <ti>-l</ti> |
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- <ti>--ldpath</ti> |
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- <ti>Scan all directories in /etc/ld.so.conf</ti> |
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-</tr> |
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-<tr> |
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- <ti>-R</ti> |
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- <ti>--recursive</ti> |
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- <ti>Scan directories recursively</ti> |
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-</tr> |
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-<tr> |
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- <ti>-m</ti> |
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- <ti>--mount</ti> |
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- <ti>Don't recursively cross mount points</ti> |
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-</tr> |
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-<tr> |
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- <ti>-y</ti> |
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- <ti>--symlink</ti> |
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- <ti>Don't scan symlinks</ti> |
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-</tr> |
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-<tr> |
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- <ti>-A</ti> |
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- <ti>--archives</ti> |
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- <ti>Scan archives (.a files)</ti> |
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-</tr> |
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-<tr> |
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- <ti>-L</ti> |
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- <ti>--ldcache</ti> |
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- <ti>Utilize ld.so.cache information (use with -r/-n)</ti> |
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-</tr> |
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-<tr> |
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- <ti>-X</ti> |
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- <ti>--fix</ti> |
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- <ti>Try and 'fix' bad things (use with -r/-e)</ti> |
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-</tr> |
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-<tr> |
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- <ti>-z [arg]</ti> |
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- <ti>--setpax [arg]</ti> |
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- <ti>Sets EI_PAX/PT_PAX_FLAGS to [arg] (use with -Xx)</ti> |
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-</tr> |
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-<tr> |
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- <th>Option</th> |
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- <th>Long Option</th> |
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- <th>Description</th> |
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-</tr> |
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-<tr> |
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- <ti>-x</ti> |
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- <ti>--pax</ti> |
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- <ti>Print PaX markings</ti> |
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-</tr> |
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-<tr> |
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- <ti>-e</ti> |
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- <ti>--header</ti> |
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- <ti>Print GNU_STACK/PT_LOAD markings</ti> |
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-</tr> |
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-<tr> |
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- <ti>-t</ti> |
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- <ti>--textrel</ti> |
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- <ti>Print TEXTREL information</ti> |
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-</tr> |
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-<tr> |
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- <ti>-r</ti> |
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- <ti>--rpath</ti> |
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- <ti>Print RPATH information</ti> |
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-</tr> |
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-<tr> |
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- <ti>-n</ti> |
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- <ti>--needed</ti> |
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- <ti>Print NEEDED information</ti> |
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-</tr> |
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-<tr> |
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- <ti>-i</ti> |
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- <ti>--interp</ti> |
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- <ti>Print INTERP information</ti> |
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-</tr> |
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-<tr> |
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- <ti>-b</ti> |
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- <ti>--bind</ti> |
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- <ti>Print BIND information</ti> |
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-</tr> |
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-<tr> |
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- <ti>-S</ti> |
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- <ti>--soname</ti> |
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- <ti>Print SONAME information</ti> |
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-</tr> |
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-<tr> |
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- <ti>-s [arg]</ti> |
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- <ti>--symbol [arg]</ti> |
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- <ti>Find a specified symbol</ti> |
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-</tr> |
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-<tr> |
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- <ti>-k [arg]</ti> |
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- <ti>--section [arg]</ti> |
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- <ti>Find a specified section</ti> |
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-</tr> |
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-<tr> |
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- <ti>-N [arg]</ti> |
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- <ti>--lib [arg]</ti> |
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- <ti>Find a specified library</ti> |
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-</tr> |
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-<tr> |
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- <ti>-g</ti> |
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- <ti>--gmatch</ti> |
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- <ti>Use strncmp to match libraries. (use with -N)</ti> |
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-</tr> |
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-<tr> |
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- <ti>-T</ti> |
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- <ti>--textrels</ti> |
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- <ti>Locate cause of TEXTREL</ti> |
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-</tr> |
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-<tr> |
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- <ti>-E [arg]</ti> |
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- <ti>--etype [arg]</ti> |
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- <ti>Print only ELF files matching etype ET_DYN,ET_EXEC ...</ti> |
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-</tr> |
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-<tr> |
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- <ti>-M [arg]</ti> |
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- <ti>--bits [arg]</ti> |
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- <ti>Print only ELF files matching numeric bits</ti> |
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-</tr> |
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-<tr> |
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- <ti>-a</ti> |
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- <ti>--all</ti> |
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- <ti>Print all scanned info (-x -e -t -r -b)</ti> |
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-</tr> |
| 258 |
-<tr> |
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- <th>Option</th> |
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- <th>Long Option</th> |
| 261 |
- <th>Description</th> |
| 262 |
-</tr> |
| 263 |
-<tr> |
| 264 |
- <ti>-q</ti> |
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- <ti>--quiet</ti> |
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- <ti>Only output 'bad' things</ti> |
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-</tr> |
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-<tr> |
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- <ti>-v</ti> |
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- <ti>--verbose</ti> |
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- <ti>Be verbose (can be specified more than once)</ti> |
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-</tr> |
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-<tr> |
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- <ti>-F [arg]</ti> |
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- <ti>--format [arg]</ti> |
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- <ti>Use specified format for output</ti> |
| 277 |
-</tr> |
| 278 |
-<tr> |
| 279 |
- <ti>-f [arg]</ti> |
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- <ti>--from [arg]</ti> |
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- <ti>Read input stream from a filename</ti> |
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-</tr> |
| 283 |
-<tr> |
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- <ti>-o [arg]</ti> |
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- <ti>--file [arg]</ti> |
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- <ti>Write output stream to a filename</ti> |
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-</tr> |
| 288 |
-<tr> |
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- <ti>-B</ti> |
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- <ti>--nobanner</ti> |
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- <ti>Don't display the header</ti> |
| 292 |
-</tr> |
| 293 |
-<tr> |
| 294 |
- <ti>-h</ti> |
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- <ti>--help</ti> |
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- <ti>Print this help and exit</ti> |
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-</tr> |
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-<tr> |
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- <ti>-V</ti> |
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- <ti>--version</ti> |
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- <ti>Print version and exit</ti> |
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-</tr> |
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-</table> |
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- |
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-<p> |
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-The format specifiers for the <c>-F</c> option are given in the following table. |
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-Prefix each specifier with <c>%</c> (verbose) or <c>#</c> (silent) accordingly. |
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-</p> |
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- |
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-<table> |
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-<tr> |
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- <th>Specifier</th> |
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- <th>Full Name</th> |
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- <th>Specifier</th> |
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- <th>Full Name</th> |
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-</tr> |
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-<tr> |
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- <ti>F</ti> |
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- <ti>Filename</ti> |
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- <ti>x</ti> |
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- <ti>PaX Flags</ti> |
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-</tr> |
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-<tr> |
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- <ti>e</ti> |
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- <ti>STACK/RELRO</ti> |
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- <ti>t</ti> |
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- <ti>TEXTREL</ti> |
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-</tr> |
| 329 |
-<tr> |
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- <ti>r</ti> |
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- <ti>RPATH</ti> |
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- <ti>n</ti> |
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- <ti>NEEDED</ti> |
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-</tr> |
| 335 |
-<tr> |
| 336 |
- <ti>i</ti> |
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- <ti>INTERP</ti> |
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- <ti>b</ti> |
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- <ti>BIND</ti> |
| 340 |
-</tr> |
| 341 |
-<tr> |
| 342 |
- <ti>s</ti> |
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- <ti>Symbol</ti> |
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- <ti>N</ti> |
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- <ti>Library</ti> |
| 346 |
-</tr> |
| 347 |
-<tr> |
| 348 |
- <ti>o</ti> |
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- <ti>Type</ti> |
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- <ti>p</ti> |
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- <ti>File name</ti> |
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-</tr> |
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-<tr> |
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- <ti>f</ti> |
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- <ti>Base file name</ti> |
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- <ti>k</ti> |
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- <ti>Section</ti> |
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-</tr> |
| 359 |
-<tr> |
| 360 |
- <ti>a</ti> |
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- <ti>ARCH/e_machine</ti> |
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- <ti> </ti> |
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- <ti> </ti> |
| 364 |
-</tr> |
| 365 |
-</table> |
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- |
| 367 |
-</body> |
| 368 |
-</section> |
| 369 |
-<section> |
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-<title>Using scanelf for Text Relocations</title> |
| 371 |
-<body> |
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- |
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-<p> |
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-As an example, we will use <c>scanelf</c> to find binaries containing text |
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-relocations. |
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-</p> |
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- |
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-<p> |
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-A relocation is an operation that rewrites an address in a loaded segment. Such |
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-an address rewrite can happen when a segment has references to a shared object |
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-and that shared object is loaded in memory. In this case, the references are |
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-substituted with the real address values. Similar events can occur inside the |
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-shared object itself. |
| 384 |
-</p> |
| 385 |
- |
| 386 |
-<p> |
| 387 |
-A text relocation is a relocation in the text segment. Since text segments |
| 388 |
-contain executable code, system administrators might prefer not to have these |
| 389 |
-segments writable. This is perfectly possible, but since text relocations |
| 390 |
-actually write in the text segment, it is not always feasible. |
| 391 |
-</p> |
| 392 |
- |
| 393 |
-<p> |
| 394 |
-If you want to eliminate text relocations, you will need to make sure |
| 395 |
-that the application and shared object is built with <e>Position Independent |
| 396 |
-Code</e> (PIC), making references obsolete. This not only increases security, |
| 397 |
-but also increases the performance in case of shared objects (allowing writes in |
| 398 |
-the text segment requires a swap space reservation and a private copy of the |
| 399 |
-shared object for each application that uses it). |
| 400 |
-</p> |
| 401 |
- |
| 402 |
-<p> |
| 403 |
-The following example will search your library paths recursively, without |
| 404 |
-leaving the mounted file system and ignoring symbolic links, for any ELF binary |
| 405 |
-containing a text relocation: |
| 406 |
-</p> |
| 407 |
- |
| 408 |
-<pre caption="Scanning the system for text relocation binaries"> |
| 409 |
-# <i>scanelf -lqtmyR</i> |
| 410 |
-</pre> |
| 411 |
- |
| 412 |
-<p> |
| 413 |
-If you want to scan your entire system for <e>any</e> file containing text |
| 414 |
-relocations: |
| 415 |
-</p> |
| 416 |
- |
| 417 |
-<pre caption="Scanning the entire system for text relocation files"> |
| 418 |
-# <i>scanelf -qtmyR /</i> |
| 419 |
-</pre> |
| 420 |
- |
| 421 |
-</body> |
| 422 |
-</section> |
| 423 |
-<section> |
| 424 |
-<title>Using scanelf for Specific Header</title> |
| 425 |
-<body> |
| 426 |
- |
| 427 |
-<p> |
| 428 |
-The scanelf util can be used to quickly identify files that contain a |
| 429 |
-given section header using the -k .section option. |
| 430 |
-</p> |
| 431 |
- |
| 432 |
-<p> |
| 433 |
-In this example we are looking for all files in /usr/lib/debug |
| 434 |
-recursively using a format modifier with quiet mode enabled that have been |
| 435 |
-stripped. A stripped elf will lack a .symtab entry, so we use the '!' |
| 436 |
-to invert the matching logic. |
| 437 |
-</p> |
| 438 |
- |
| 439 |
-<pre caption="Scanning for stripped or non stripped executables"> |
| 440 |
-# <i>scanelf -k '!.symtab' /usr/lib/debug -Rq -F%F#k</i> |
| 441 |
-</pre> |
| 442 |
- |
| 443 |
-</body> |
| 444 |
-</section> |
| 445 |
-<section> |
| 446 |
-<title>Using scanelf for Specific Segment Markings</title> |
| 447 |
-<body> |
| 448 |
- |
| 449 |
-<p> |
| 450 |
-Each segment has specific flags assigned to it in the Program Header of the |
| 451 |
-binary. One of those flags is the type of the segment. Interesting values are |
| 452 |
-PT_LOAD (the segment must be loaded in memory from file), PT_DYNAMIC (the |
| 453 |
-segment contains dynamic linking information), PT_INTERP (the segment |
| 454 |
-contains the name of the program interpreter), PT_GNU_STACK (a GNU extension |
| 455 |
-for the ELF format, used by some stack protection mechanisms), and PT_PAX_FLAGS |
| 456 |
-(a PaX extension for the ELF format, used by the security-minded |
| 457 |
-<uri link="http://pax.grsecurity.net/">PaX Project</uri>. |
| 458 |
-</p> |
| 459 |
- |
| 460 |
-<p> |
| 461 |
-If we want to scan all executables in the current working directory, PATH |
| 462 |
-environment and library paths and report those who have a writable and |
| 463 |
-executable PT_LOAD or PT_GNU_STACK marking, you could use the following command: |
| 464 |
-</p> |
| 465 |
- |
| 466 |
-<pre caption="Scanning for Write/eXecute flags for PT_LOAD and PT_GNU_STACK"> |
| 467 |
-# <i>scanelf -lpqe .</i> |
| 468 |
-</pre> |
| 469 |
- |
| 470 |
-</body> |
| 471 |
-</section> |
| 472 |
-<section> |
| 473 |
-<title>Using scanelf's Format Modifier Handler</title> |
| 474 |
-<body> |
| 475 |
- |
| 476 |
-<p> |
| 477 |
-A useful feature of the <c>scanelf</c> utility is the format modifier handler. |
| 478 |
-With this option you can control the output of <c>scanelf</c>, thereby |
| 479 |
-simplifying parsing the output with scripts. |
| 480 |
-</p> |
| 481 |
- |
| 482 |
-<p> |
| 483 |
-As an example, we will use <c>scanelf</c> to print the file names that contain |
| 484 |
-text relocations: |
| 485 |
-</p> |
| 486 |
- |
| 487 |
-<pre caption="Example of the scanelf format modifier handler"> |
| 488 |
-# <i>scanelf -l -p -R -q -F "%F #t"</i> |
| 489 |
+utility. What it does is check all the libraries linked statically by the |
| 490 |
+binaries using <c>ldd</c> and then smartly add the paxmarks of those libraries |
| 491 |
+to generate the new set. As a result if <path>/usr/games/bin/armagetronad</path> |
| 492 |
+links with <path>/usr/lib64/libGL.so.1</path> which has the <e>-m</e> PaX mark |
| 493 |
+(allow RWX mappings) because you are using a llvm requiring graphics driver |
| 494 |
+you'll get that binary marked with the <e>-m</e> PaX mark too since it needs it. |
| 495 |
+Below you can see how to run it. |
| 496 |
+</p> |
| 497 |
+ |
| 498 |
+<pre caption="Propagating the PaX marks from the libraries"> |
| 499 |
+# <i>mv /etc/grsec/learning.roles /etc/grsec/policy</i> |
| 500 |
+# <i>chmod 0600 /etc/grsec/policy</i> |
| 501 |
</pre> |
| 502 |
|
| 503 |
-</body> |
| 504 |
-</section> |
| 505 |
-</chapter> |
| 506 |
- |
| 507 |
-<chapter id="pspax"> |
| 508 |
-<title>Listing PaX Flags and Capabilities</title> |
| 509 |
-<section> |
| 510 |
-<title>About PaX</title> |
| 511 |
-<body> |
| 512 |
- |
| 513 |
-<p> |
| 514 |
-<uri link="http://pax.grsecurity.net">PaX</uri> is a project hosted by the <uri |
| 515 |
-link="http://www.grsecurity.net">grsecurity</uri> project. Quoting the <uri |
| 516 |
-link="http://pax.grsecurity.net/docs/pax.txt">PaX documentation</uri>, its main |
| 517 |
-goal is "to research various defense mechanisms against the exploitation of |
| 518 |
-software bugs that give an attacker arbitrary read/write access to the |
| 519 |
-attacked task's address space. This class of bugs contains among others |
| 520 |
-various forms of buffer overflow bugs (be they stack or heap based), user |
| 521 |
-supplied format string bugs, etc." |
| 522 |
-</p> |
| 523 |
- |
| 524 |
-<p> |
| 525 |
-To be able to benefit from these defense mechanisms, you need to run a Linux |
| 526 |
-kernel patched with the latest PaX code. The <uri |
| 527 |
-link="http://hardened.gentoo.org">Hardened Gentoo</uri> project supports PaX and |
| 528 |
-its parent project, grsecurity. The supported kernel package is |
| 529 |
-<c>sys-kernel/hardened-sources</c>. |
| 530 |
-</p> |
| 531 |
- |
| 532 |
-<p> |
| 533 |
-The Gentoo/Hardened project has a <uri |
| 534 |
-link="/proj/en/hardened/pax-quickstart.xml">Gentoo PaX Quickstart Guide</uri> |
| 535 |
-for your reading pleasure. |
| 536 |
-</p> |
| 537 |
- |
| 538 |
-</body> |
| 539 |
-</section> |
| 540 |
-<section> |
| 541 |
-<title>Flags and Capabilities</title> |
| 542 |
-<body> |
| 543 |
- |
| 544 |
-<p> |
| 545 |
-If your toolchain supports it, your binaries can have additional PaX flags in |
| 546 |
-their Program Header. The following flags are supported: |
| 547 |
-</p> |
| 548 |
- |
| 549 |
-<table> |
| 550 |
-<tr> |
| 551 |
- <th>Flag</th> |
| 552 |
- <th>Name</th> |
| 553 |
- <th>Description</th> |
| 554 |
-</tr> |
| 555 |
-<tr> |
| 556 |
- <ti>P</ti> |
| 557 |
- <ti>PAGEEXEC</ti> |
| 558 |
- <ti> |
| 559 |
- Refuse code execution on writable pages based on the NX bit |
| 560 |
- (or emulated NX bit) |
| 561 |
- </ti> |
| 562 |
-</tr> |
| 563 |
-<tr> |
| 564 |
- <ti>S</ti> |
| 565 |
- <ti>SEGMEXEC</ti> |
| 566 |
- <ti> |
| 567 |
- Refuse code execution on writable pages based on the |
| 568 |
- segmentation logic of IA-32 |
| 569 |
- </ti> |
| 570 |
-</tr> |
| 571 |
-<tr> |
| 572 |
- <ti>E</ti> |
| 573 |
- <ti>EMUTRAMP</ti> |
| 574 |
- <ti> |
| 575 |
- Allow known code execution sequences on writable pages that |
| 576 |
- should not cause any harm |
| 577 |
- </ti> |
| 578 |
-</tr> |
| 579 |
-<tr> |
| 580 |
- <ti>M</ti> |
| 581 |
- <ti>MPROTECT</ti> |
| 582 |
- <ti> |
| 583 |
- Prevent the creation of new executable code to the process |
| 584 |
- address space |
| 585 |
- </ti> |
| 586 |
-</tr> |
| 587 |
-<tr> |
| 588 |
- <ti>R</ti> |
| 589 |
- <ti>RANDMMAP</ti> |
| 590 |
- <ti> |
| 591 |
- Randomize the stack base to prevent certain stack overflow |
| 592 |
- attacks from being successful |
| 593 |
- </ti> |
| 594 |
-</tr> |
| 595 |
-<tr> |
| 596 |
- <ti>X</ti> |
| 597 |
- <ti>RANDEXEC</ti> |
| 598 |
- <ti> |
| 599 |
- Randomize the address where the application maps to prevent |
| 600 |
- certain attacks from being exploitable |
| 601 |
- </ti> |
| 602 |
-</tr> |
| 603 |
-</table> |
| 604 |
- |
| 605 |
-<p> |
| 606 |
-The default Linux kernel also supports certain capabilities, grouped in the |
| 607 |
-so-called <e>POSIX.1e Capabilities</e>. You can find a listing of those |
| 608 |
-capabilities in our <uri |
| 609 |
-link="/proj/en/hardened/capabilities.xml">POSIX Capabilities</uri> document. |
| 610 |
-</p> |
| 611 |
- |
| 612 |
-</body> |
| 613 |
-</section> |
| 614 |
-<section> |
| 615 |
-<title>Using pspax</title> |
| 616 |
-<body> |
| 617 |
- |
| 618 |
-<p> |
| 619 |
-The <c>pspax</c> application, part of the <c>pax-utils</c> package, displays the |
| 620 |
-run-time capabilities of all programs you have permission for. On Linux kernels |
| 621 |
-with additional support for extended attributes (such as SELinux) those |
| 622 |
-attributes are shown as well. |
| 623 |
-</p> |
| 624 |
- |
| 625 |
-<p> |
| 626 |
-When ran, <c>pspax</c> shows the following information: |
| 627 |
-</p> |
| 628 |
- |
| 629 |
-<table> |
| 630 |
-<tr> |
| 631 |
- <th>Column</th> |
| 632 |
- <th>Description</th> |
| 633 |
-</tr> |
| 634 |
-<tr> |
| 635 |
- <ti>USER</ti> |
| 636 |
- <ti>Owner of the process</ti> |
| 637 |
-</tr> |
| 638 |
-<tr> |
| 639 |
- <ti>PID</ti> |
| 640 |
- <ti>Process id</ti> |
| 641 |
-</tr> |
| 642 |
-<tr> |
| 643 |
- <ti>PAX</ti> |
| 644 |
- <ti>Run-time PaX flags (if applicable)</ti> |
| 645 |
-</tr> |
| 646 |
-<tr> |
| 647 |
- <ti>MAPS</ti> |
| 648 |
- <ti>Write/eXecute markings for the process map</ti> |
| 649 |
-</tr> |
| 650 |
-<tr> |
| 651 |
- <ti>ELF_TYPE</ti> |
| 652 |
- <ti>Process executable type: ET_DYN or ET_EXEC</ti> |
| 653 |
-</tr> |
| 654 |
-<tr> |
| 655 |
- <ti>NAME</ti> |
| 656 |
- <ti>Name of the process</ti> |
| 657 |
-</tr> |
| 658 |
-<tr> |
| 659 |
- <ti>CAPS</ti> |
| 660 |
- <ti>POSIX.1e capabilities (see note)</ti> |
| 661 |
-</tr> |
| 662 |
-<tr> |
| 663 |
- <ti>ATTR</ti> |
| 664 |
- <ti>Extended attributes (if applicable)</ti> |
| 665 |
-</tr> |
| 666 |
-</table> |
| 667 |
|
| 668 |
<note> |
| 669 |
-<c>pspax</c> only displays these capabilities when it is linked with |
| 670 |
-the external capabilities library. This requires you to build <c>pax-utils</c> |
| 671 |
-with -DWANT_SYSCAP. |
| 672 |
+Due to the way in which <c>ldd</c> works you'll get all the libraries required |
| 673 |
+at runtime, even those required by libraries you link to (and so on recursively) |
| 674 |
+as a result <c>revdep-pax</c> will detect all dependencies in a single pass. If |
| 675 |
+the behaviour of <c>ldd</c> changes so may change the behaviour of |
| 676 |
+<c>revdep-pax</c> |
| 677 |
</note> |
| 678 |
|
| 679 |
<p> |
| 680 |
-By default, <c>pspax</c> does not show any kernel processes. If you want those |
| 681 |
-to be taken as well, use the <c>-a</c> switch. |
| 682 |
-</p> |
| 683 |
- |
| 684 |
-</body> |
| 685 |
-</section> |
| 686 |
-</chapter> |
| 687 |
- |
| 688 |
-<chapter id="dumpelf"> |
| 689 |
-<title>Programming with ELF files</title> |
| 690 |
-<section> |
| 691 |
-<title>The dumpelf Utility</title> |
| 692 |
-<body> |
| 693 |
- |
| 694 |
-<p> |
| 695 |
-With the <c>dumpelf</c> utility you can convert a ELF file into human readable C |
| 696 |
-code that defines a structure with the same image as the original ELF file. |
| 697 |
+The <c>scanelf</c> application is part of the <c>app-misc/pax-utils</c> package. |
| 698 |
+With this application you can print out information specific to the ELF |
| 699 |
+structure of a binary. The following table sums up the various options. |
| 700 |
</p> |
| 701 |
|
| 702 |
-<pre caption="dumpelf example"> |
| 703 |
-$ <i>dumpelf /bin/hostname</i> |
| 704 |
-#include <elf.h> |
| 705 |
- |
| 706 |
-<comment>/* |
| 707 |
- * ELF dump of '/bin/hostname' |
| 708 |
- * 10276 (0x2824) bytes |
| 709 |
- */</comment> |
| 710 |
- |
| 711 |
-struct { |
| 712 |
- Elf32_Ehdr ehdr; |
| 713 |
- Elf32_Phdr phdrs[8]; |
| 714 |
- Elf32_Shdr shdrs[26]; |
| 715 |
-} dumpedelf_0 = { |
| 716 |
- |
| 717 |
-.ehdr = { |
| 718 |
-<comment>(... Output stripped ...)</comment> |
| 719 |
-</pre> |
| 720 |
- |
| 721 |
</body> |
| 722 |
</section> |
| 723 |
</chapter> |
| 724 |
-</guide> |
| 725 |
+</guide> |
| 726 |
\ No newline at end of file |
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