Desarrollo Linux y software libre

Al ejecutar Tshark (la versión de consola de Wireshark) puede ocurrir el siguiente error:


carlos@maquina17:~$ sudo tshark -i eth0 -w captura.trafico.20090928.cap
Running as user "root" and group "root". This could be dangerous.
Capturing on eth0
tshark: The file to which the capture would be saved ("captura.trafico.20090928.cap") could not be opened: Permission denied.

Esto ocurre por una cuestión de diseño basada en la seguridad del software (Bug Debian #453292).

Se soluciona de dos formas distintas:

a) Creando previamente el fichero:
carlos@maquina17:~$ sudo touch captura.trafico.20090928.cap

a) Cambiando la ruta donde salvar el fichero a otra donde no haya problemas de UID.
carlos@maquina17:~$ sudo tshark -i eth0 -w /root/captura.trafico.20090928.cap

Si al ejecutar Firefox se produce este error en la consola:

carlos@WhenIGrowUp:~/personal$ firefox
Could not find compatible GRE between version 1.9.0.1 and 1.9.0.*.

Es necesario realizar los siguientes pasos:

1º) Comprobar paquete «xulrunner»

$ dpkg -l xulrunner-1.9
(...)
ii xulrunner-1.9 1.9.0.3+nobinonly- XUL + XPCOM application runner

2º) Instalarlo si no se dispone de él:

$ sudo apt-get install xulrunner

3º) Ejecutar:

$ xulrunner --register-global

Y volver a ejecutar Firefox.

Fuente: Launchpad Ubuntu

Si al ejecutar la utilidad Web-Shell se producen trazas similares a éstas:

Exception happened during processing of request from ('172.26.0.4', 35859)
Traceback (most recent call last):
File "/usr/lib/python2.6/SocketServer.py", line 281, in _handle_request_noblock
self.process_request(request, client_address)
File "/usr/lib/python2.6/SocketServer.py", line 307, in process_request
self.finish_request(request, client_address)
File "/usr/lib/python2.6/SocketServer.py", line 320, in finish_request
self.RequestHandlerClass(request, client_address, self)
File "/usr/lib/python2.6/SocketServer.py", line 615, in __init__
self.handle()
File "/usr/lib/python2.6/BaseHTTPServer.py", line 329, in handle
self.handle_one_request()
File "/usr/lib/python2.6/BaseHTTPServer.py", line 312, in handle_one_request
self.raw_requestline = self.rfile.readline()
File "/usr/lib/python2.6/socket.py", line 404, in readline
data = self._sock.recv(self._rbufsize)
Error: [('SSL routines', 'SSL23_GET_CLIENT_HELLO', 'http request')]
----------------------------------------
----------------------------------------
Exception happened during processing of request from ('172.26.0.4', 35860)
Traceback (most recent call last):
File "/usr/lib/python2.6/SocketServer.py", line 281, in _handle_request_noblock
self.process_request(request, client_address)
File "/usr/lib/python2.6/SocketServer.py", line 307, in process_request
self.finish_request(request, client_address)
File "/usr/lib/python2.6/SocketServer.py", line 320, in finish_request
self.RequestHandlerClass(request, client_address, self)
File "/usr/lib/python2.6/SocketServer.py", line 615, in __init__
self.handle()
File "/usr/lib/python2.6/BaseHTTPServer.py", line 329, in handle
self.handle_one_request()
File "/usr/lib/python2.6/BaseHTTPServer.py", line 312, in handle_one_request
self.raw_requestline = self.rfile.readline()
File "/usr/lib/python2.6/socket.py", line 404, in readline
data = self._sock.recv(self._rbufsize)
Error: [('SSL routines', 'SSL23_GET_CLIENT_HELLO', 'http request')]
----------------------------------------
----------------------------------------
Exception happened during processing of request from ('172.26.0.4', 35861)
Traceback (most recent call last):
File "/usr/lib/python2.6/SocketServer.py", line 281, in _handle_request_noblock
self.process_request(request, client_address)
File "/usr/lib/python2.6/SocketServer.py", line 307, in process_request
self.finish_request(request, client_address)
File "/usr/lib/python2.6/SocketServer.py", line 320, in finish_request
self.RequestHandlerClass(request, client_address, self)
File "/usr/lib/python2.6/SocketServer.py", line 615, in __init__
self.handle()
File "/usr/lib/python2.6/BaseHTTPServer.py", line 329, in handle
self.handle_one_request()
File "/usr/lib/python2.6/BaseHTTPServer.py", line 312, in handle_one_request
self.raw_requestline = self.rfile.readline()
File "/usr/lib/python2.6/socket.py", line 404, in readline
data = self._sock.recv(self._rbufsize)
Error: [('SSL routines', 'SSL23_GET_CLIENT_HELLO', 'http request')]
----------------------------------------

Se debe sencillamente a un uso incorrecto de la aplicación. La web se ha accedido por http cuando debe ser por https.
http://172.26.0.5:8022/
https://172.26.0.5:8022/

Además, si se desea monitorizar con Monit, es necesario añadir las siguientes líneas al fichero de configuración

#sudo nano /etc/monit/monitrc
(...)
check host WebShell_8022 with address 127.0.0.1
start program = "/usr/bin/python /etc/WebShell/webshell.py &"
stop program = "/usr/bin/killall -9 python /etc/WebShell/webshell.py"
if failed port 8022 then restart
(...)

adaptando las rutas, y reiniciar Monit

#sudo /etc/init.d/monit restart

[ Update]:Newer versions of Xplico have solved this problem.

During the installation of Xplico, network traffic analyzer and sniffer (pcap compatible), may happen this error:

#dpkg -i xplico_0.5.2_i386.deb
After this operation, 0B of additional disk space will be used.
Setting up xplico (0.5.2) ...
chown: cannot access `/opt/xplico/xi': No such file or directory
dpkg: error processing xplico (--configure):
subprocess post-installation script returned error exit status 1
Errors were encountered while processing:
xplico
E: Sub-process /usr/bin/dpkg returned an error code (1)

If you create that missing directory by yourself and try to reinstall, another error will be prompted:

root@ubuntu:/home/adminuser/Desktop# apt-get install xplico
chmod: cannot access `/opt/xplico/xplico.db': No such file or directory

Till next package version, the current solution is uninstall and reinstall using this method:

1º) Uninstall:
# sudo dpkg -r xplico

2º) Manually delete the lines which mention port 9876
# nano etc/apache2/ports.conf

3º) Install the package with gdebi:
adminuser@ubuntu:~/Desktop$ sudo apt-get install gdebi

adminuser@ubuntu:~/Desktop$ sudo gdebi xplico_0.5.2_i386.deb
Reading package lists: Done
Reading state information: Done
Reading state information: Done
Reading state information: Done
Reading state information: Done
Xplico is a Network Forensic Analysis Tool (NFAT)
The goal of Xplico is extract from an internet traffic capture the applications data contained.
For example, from a pcap file Xplico extracts each email (POP, IMAP, and SMTP protocols), all HTTP contents, each VoIP call (SIP), FTP, TFTP, and so on. Xplico is not a network protocol analyzer.
Do you want to install the software package? [y/N]:Y
Selecting previously deselected package xplico.
(Reading database ... 136557 files and directories currently installed.)
Unpacking xplico (from xplico_0.5.2_i386.deb) ...
Setting up xplico (0.5.2) ...
Module php5 already enabled
Module rewrite already enabled
Thanks to Gianluca Costa

El formato de backups de Plesk es distinto al habitual tar.gz, por lo que hay que utilizar una herramienta específica para, posteriormente si, conseguir un tar.gz

1º) Bajar, descomprimir e instalar ripmime

2º) Procesar el fichero con ripmine:
# ripmime -i backup-20090908-mi-dominio.com -d directorioBackupRestaurada

3º) Descomprimir el contenido:
# tar -ztvf directorioBackupRestaurada/*

Fuente: http://forums.deftechgroup.com/showthread.php?t=1087

Si a la hora de realizar una compilación se produce un error similar al siguiente:

/usr/bin/msgmerge --update ar.po amule.pot
/bin/sh: /usr/bin/msgmerge: not found

Es facilmente solucionable instalando el paquete gettext:

carlos@WhenIGrowUp:~/amule/amule$ sudo apt-get install gettext
Leyendo lista de paquetes... Hecho
Creando árbol de dependencias
Leyendo la información de estado... Hecho
Paquetes sugeridos:
cvs gettext-doc
Se instalarán los siguientes paquetes NUEVOS:
gettext
0 actualizados, 1 se instalarán, 0 para eliminar y 81 no actualizados.
Necesito descargar 2067kB de archivos.
Se utilizarán 8221kB de espacio de disco adicional después de desempaquetar.
Des:1 http://archive.ubuntu.com hardy/main gettext 0.17-2ubuntu1 [2067kB]
Descargados 2067kB en 1s (1182kB/s)
Seleccionando el paquete gettext previamente no seleccionado.
(Leyendo la base de datos ...
152201 ficheros y directorios instalados actualmente.)
Desempaquetando gettext (de .../gettext_0.17-2ubuntu1_amd64.deb) ...
Configurando gettext (0.17-2ubuntu1) ...
Processing triggers for libc6 ...
ldconfig deferred processing now taking place

Al ejecutar una aplicación php en un Apache, puede suceder el siguiente error:

The requested URL /var/www/aplicacion1/mysite/public/index.php/auth/login was not found on this server.

Esto probablemente se deba a una directiva especificada en el archivo .htaccess, que solicita al servidor web un determinado comportamiento.

RewriteEngine on
RewriteCond %{REQUEST_URI} !/public/.*
RewriteCond %{REQUEST_URI} !/images/.*
RewriteCond %{REQUEST_URI} !/layout/.*
RewriteRule .* index.php
php_flag magic_quotes_gpc off
php_flag register_globals off
php_value max_execution_time 120

Generalmente el problema es debido a la ausencia del módulo rewrite en la configuración de Apache. Para ello es necesario realizar tres pasos:

1º) Activar el módulo rewrite en Apache2.

ubuntu@ubuntu:/$ sudo a2enmod rewrite
Enabling module rewrite.
Run '/etc/init.d/apache2 restart' to activate new configuration!

2º) Modificar la configuración de Apache para indicar a qué sites alojados debe aplicarse el módulo «rewrite», sustituyendo «AllowOverride none» por AllowOverride All«.
ubuntu@ubuntu:/$ sudo nano /etc/apache2/sites-enabled/000-default

<VirtualHost *:80>
ServerAdmin webmaster@localhost
DocumentRoot /var/www/
<Directory />
Options FollowSymLinks
AllowOverride All
</Directory>
(…)

Realizar este cambio por tanto en las entradas en las que se quiera aplicar el módulo rewrite, generalmente en todas.

3º) Reiniciar Apache

root@ubuntu:/etc/apache2/sites-enabled# /etc/init.d/apache2 restart
* Restarting web server htcacheclean                                                                                                               ...not running
apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1 for ServerName
apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1 for ServerName
[ OK ]

Y de esta manera se consigue activar y configurar el módulo mod_rewrite en Apache2.