Usando um servidor samba com controle de acesso ao compartilhamento.

Colaboração: Geraldo Coelho

Data de Publicação: 16 de Maio de 2004

Neste exemplo usamos a opção "Security = Domain" mas também pode ser usado com a "Security = Server"

Para que se tenha acesso ao compartilhamento, exceto com as opções configuradas "guest ok" ou "guest only" tem que se ter um conta na máquina.

Para fazer isso automáticamente após a autenticação do usuário, adcione a linha para seu smb.conf

add user script = /etc/samba/add_user %u

Exemplo de um compartilhamento.

[sistemas]
   path = /sistemas
   write list = @projeto
  force create mode = 0775
  force directory mode = 0775

Segue um exemplo de acesso de leitura para todos que logam no PDC e de escrita para alguns, temos aqui duas camadas de segurança a do unix com permissão de diretório e a do samba com "write list".

Primeiro crie os usuários que terão acesso de escrita e crie um grupo default para eles.

Usuários do grupo "projeto" podem gravar, os demais usuários que acessar o compartilhamento, após se autenticarem se já não tiver uma conta será criada e o grupo padrão será o "sistema".

###### Debian
addgroup projeto
addgroup sistema

mkdir /sistemas
chmod 775 /sistemas (propriedade do root)

mkdir /sistemas/dados
chmod 775 /sistemas/dados
chown root.projeto /sistemas/dados

useradd -g projeto -s /bin/false -d /sistemas nome_do_usuario

#!/bin/sh

useradd -g sistema -s /bin/false -d /sistemas $1

exit 0

######## OpenBSD
groupadd projeto
groupadd sistema

mkdir /sistemas
chmod 775 /sistemas (propriedade do root)

mkdir /sistemas/dados
chmod 775 /sistemas/dados
chown root.projeto /sistemas/dados

useradd  -s /sbin/nologin  -d /sistemas -g projeto nome_do_usuario

#!/bin/sh


useradd  -s /sbin/nologin  -d /sistemas -g sistema $1

exit 0

New Bug-Infested Distro Eases Transition From Windows To Linux

Colaboração: Roberto Romani

Sensacional a nova distribuição Linux "Notdows". Ela foi feita sob medida para quem está migrando do Windows para o Linux. A grande vantagem é o componente killrandom. É um daemon que seleciona randomicamente um processo e o mata. O objetivo é simular as travadas do widows.

New Bug-Infested Distro Eases Transition From Windows To Linux

Fake News written by James Baughn on May 3, 2004 from the my-kind-of-development-job dept. http://humorix.org/articles/2004/05/transition/

In what promoters are calling a "Linux distribution built for managers by managers", a new company called Pee-aitch-bee Enterprises has unveiled "Notdows", a distro designed to "ease the transition from Windows to Linux in every way possible."

A key component of Notdows is the killrandom daemon process, which randomly kills running processes, faithfully simulating the Windows experience. Over time, however, killrandom will operate less frequently, allowing the user to smoothly transition to a stable operating system.

"Ordinary distros built by geeks are designed to be as stable as possible," said a Pee-aitch-bee developer/manager. "This does not work well for some naive ex-Windows users, who become disoriented and lost in such a foreign environment. While recent versions of Windows are more stable than predecessors, the difference between Windows and Linux can still be quite jarring. We hope to ween these users away from Windows' flakiness without causing unnecessary emotional duress."

The development process for Notdows is markedly different from most open source projects. "We want our system to have an optimum number of bugs to closely match Windows. Our developers are rewarded for reaching a target of 1 bug per 1,000 lines of code. In some cases bugs must be intentionally added in order to achieve this objective. Our development platform, code-named Reverse Bugzilla, makes this possible."

In some cases, however, Notdows has developed nasty bugs that cancelled out other bugs. "We discovered that killrandom 1.2.23 had an ugly flaw that allowed the program to kill itself, immediately causing the system to run at maximum stability. It took awhile to diagnose the problem, but we knew something was fishy when one of our development machines reached an uptime of 61 days -- the average for a fresh Notdows installation is 3 days between reboots."

The Notdows developers do take security seriously, however. "We like bugs, but not security holes," the developer said. "The last thing we want is for crackers to trash somebody's system, providing an opportunity for the user to wipe their hard drive and decide to go back to Windows. However, for peace of mind, we do include a dummy anti-virus program that pretends to scan files but otherwise does nothing except make grinding sounds on the hard drive."

In another nod to Windows, the standard Notdows system costs an obscenely large amount of money. "While we do make the whole thing available for free from our FTP site, we really don't want our target audience to know that. They believe that 'more expensive' is always synonymous with 'more quality'. What they don't know about anonymous FTP isn't going to hurt them..."