a6074d4c3d
Stylistic and other fixes R=andybons@chromium.org BUG=524256 Review URL: https://codereview.chromium.org/1318153003 Cr-Commit-Position: refs/heads/master@{#346569}
143 lines
4.3 KiB
Markdown
143 lines
4.3 KiB
Markdown
# Debuggin SSL on Linux
|
|
|
|
To help anyone looking at the SSL code, here are a few tips I've found handy.
|
|
|
|
[TOC]
|
|
|
|
## Building your own NSS
|
|
|
|
In order to use a debugger with the NSS library, it helps to build NSS yourself.
|
|
Here's how I did it:
|
|
|
|
First, read
|
|
[Network Security Services](http://www.mozilla.org/projects/security/pki/nss/nss-3.11.4/nss-3.11.4-build.html)
|
|
and/or
|
|
[Build instructions](https://developer.mozilla.org/En/NSS_reference/Building_and_installing_NSS/Build_instructions).
|
|
|
|
Then, to build the most recent source tarball:
|
|
|
|
```shell
|
|
cd $HOME
|
|
wget ftp://ftp.mozilla.org/pub/mozilla.org/security/nss/releases/NSS_3_12_RTM/src/nss-3.12-with-nspr-4.7.tar.gz
|
|
tar -xzvf nss-3.12-with-nspr-4.7.tar.gz
|
|
cd nss-3.12/
|
|
cd mozilla/security/nss/
|
|
make nss_build_all
|
|
```
|
|
|
|
Sadly, the latest release, 3.12.2, isn't available as a tarball, so you have to
|
|
build it from cvs:
|
|
|
|
```shell
|
|
cd $HOME
|
|
mkdir nss-3.12.2
|
|
cd nss-3.12.2
|
|
export CVSROOT=:pserver:anonymous@cvs-mirror.mozilla.org:/cvsroot
|
|
cvs login
|
|
cvs co -r NSPR_4_7_RTM NSPR
|
|
cvs co -r NSS_3_12_2_RTM NSS
|
|
cd mozilla/security/nss/
|
|
make nss_build_all
|
|
```
|
|
|
|
## Linking against your own NSS
|
|
|
|
Sadly, I don't know of a nice way to do this; I always do
|
|
|
|
hammer --verbose net > log 2>&1
|
|
|
|
then grab the line that links my app and put it into a shell script link.sh,
|
|
and edit it to include the line
|
|
|
|
DIR=$HOME/nss-3.12.2/mozilla/dist/Linux2.6_x86_glibc_PTH_DBG.OBJ/lib
|
|
|
|
and insert a `-L$DIR` right before the `-lnss3`.
|
|
|
|
Note that hammer often builds the app in one, deeply buried, place, then copies
|
|
it into Hammer for ease of use. You'll probably want to make your `link.sh` do
|
|
the same thing.
|
|
|
|
Then, after a source code change, do the usual `hammer net` followed by
|
|
`sh link.sh`.
|
|
|
|
Then, to run the resulting app, use a script like
|
|
|
|
## Running against your own NSS
|
|
|
|
Create a script named `run.sh` like this:
|
|
|
|
```sh
|
|
#!/bin/sh
|
|
set -x
|
|
DIR=$HOME/nss-3.12.2/mozilla/dist/Linux2.6_x86_glibc_PTH_DBG.OBJ/lib
|
|
export LD_LIBRARY_PATH=$DIR
|
|
"$@"
|
|
```
|
|
|
|
Then run your app with
|
|
|
|
sh run.sh Hammer/foo
|
|
|
|
Or, to debug it, do
|
|
|
|
sh run.sh gdb Hammer/foo
|
|
|
|
## Logging
|
|
|
|
There are several flavors of logging you can turn on.
|
|
|
|
* `SSLClientSocketNSS` can log its state transitions and function calls using
|
|
`base/logging.cc`. To enable this, edit `net/base/ssl_client_socket_nss.cc`
|
|
and change `#if 1` to `#if 0`. See `base/logging.cc` for where the output
|
|
goes (on Linux, it's usually stderr).
|
|
|
|
* `HttpNetworkTransaction` and friends can log its state transitions using
|
|
`base/trace_event.cc`. To enable this, arrange for your app to call
|
|
`base::TraceLog::StartTracing()`. The output goes to a file named
|
|
`trace...pid.log` in the same directory as the executable (e.g.
|
|
`Hammer/trace_15323.log`).
|
|
|
|
* `NSS` itself can log some events. To enable this, set the environment
|
|
variables `SSLDEBUGFILE=foo.log SSLTRACE=99 SSLDEBUG=99` before running
|
|
your app.
|
|
|
|
## Network Traces
|
|
|
|
http://wiki.wireshark.org/SSL describes how to decode SSL traffic. Chromium SSL
|
|
unit tests that use `net/base/ssl_test_util.cc` to set up their servers always
|
|
use port 9443 with `net/data/ssl/certificates/ok_cert.pem`, and port 9666 with
|
|
`net/data/ssl/certificates/expired_cert.pem` This makes it easy to configure
|
|
Wireshark to decode the traffic: do
|
|
|
|
Edit / Preferences / Protocols / SSL, and in the "RSA Keys List" box, enter
|
|
|
|
127.0.0.1,9443,http,<path to ok_cert.pem>;127.0.0.1,9666,http,<path to expired_cert.pem>
|
|
|
|
e.g.
|
|
|
|
127.0.0.1,9443,http,/home/dank/chromium/src/net/data/ssl/certificates/ok_cert.pem;127.0.0.1,9666,http,/home/dank/chromium/src/net/data/ssl/certificates/expired_cert.pem
|
|
|
|
Then capture all tcp traffic on interface lo, and run your test.
|
|
|
|
## Valgrinding NSS
|
|
|
|
Read https://developer.mozilla.org/en/NSS_Memory_allocation and do
|
|
|
|
export NSS_DISABLE_ARENA_FREE_LIST=1
|
|
|
|
before valgrinding if you want to find where a block was originally allocated.
|
|
|
|
If you get unsymbolized entries in NSS backtraces, try setting:
|
|
|
|
export NSS_DISABLE_UNLOAD=1
|
|
|
|
(Note that if you use the Chromium valgrind scripts like
|
|
`tools/valgrind/chrome_tests.sh` or `tools/valgrind/valgrind.sh` these will both
|
|
be set automatically.)
|
|
|
|
## Support forums
|
|
|
|
If you have nonconfidential questions about NSS, check
|
|
[the newsgroup](http://groups.google.com/group/mozilla.dev.tech.crypto).
|
|
The NSS maintainer monitors that group and gives good answers.
|