Pwning Your Phone with Adhearsion and Asterisk

Pwning Your Phone

with Adhearsion and Asterisk

Past & Today

Started January of 2005 at an ITSP

I got into Rails. Started rewrite last summer

Launched last Christmas

Spoke at O’Reilly Emerging Telephony 2007

4 page article in Linux Journal last March

Section in next O’Reilly Asterisk book

Adhearsion in a Nutshell

Build very complex phone systems with Ruby

Open source (LGPL) framework

Builds atop Asterisk without losing anything

More of a “collaboration framework” than an “Asterisk development framework”

Ad hear sion = “adhesion” you can “hear”

Not Rails. For the VoIP domain specifically!

Why VoIP Rocks

VoIP skills are awesome for hackers

VoIP can dramatically cut a business’ expenses

VoIP skills look good on a resume

Builds skills in CS, SE, EE, UX, BA, and all kinds of other acronyms

Plus, now you can use Ruby!

(why the lucky stiff???)

Fun VoIP Projects

Unlock apartment door with your cell phone

Control your hacked Xbox Media Center

Rarely ever pay for a phone call

Make your own crazy reminder system

Control anything with voice commands

Phone controlled Roomba

Dave Troy’s Asterisk-Powered Roomba Dave’s also writing “Telephony with Ruby”. Will be published by The Prags in November

What is ? What is ?

Open source phone call manager (PBX)

Sponsored and developed by Digium, Inc.

Revolutionized the telecom world forever

Makes hackers really happy

Makes cash flow statements really happy

Does everything you could want with a phone

Existing Control Grammars Suck At...

Conditional looping & branching

Variables

Complex data structures

Database/LDAP integration

Use of third-party libraries

Extending the language

Error handling

Date & time handling

Pattern matching

...to name just a few things!

Old Dialplan Example [macro-dial-iax] exten => s,1,SetGlobalVar(FOUNDME=ANSWER) exten => s,2,GotoIf($[${LEN(${ARG1})} = 10]?2:4) exten => s,3,SetVar(NumToDial=1${ARG1}) exten => s,4,Goto(s,6) exten => s,5,SetVar(NumToDial=${ARG1}) ... From extensions.conf

Why Use Adhearsion?

Asterisk rocks but its barrier to entry sucks

Grammar feels like assembler or Excel

Adds many new features to your PBX

Adhearsion does dramatically improve Asterisk

Database integration with ActiveRecord

Last but not least, integrate VoIP and Rails!

Before Adhearsion.

Before Adhearsion. After Adhearsion.

Other Aspects of Adhearsion

Helper system for extending the framework

One of the first times VoIP code can be traded

Integrates with on-phone micro-browsers

Use other collaboration technologies together

Instant messaging, growl, weather, reverse number lookup, etc...

Getting Started

Asterisk?! Isn’t that hard to install?

No! Use Digium’s AsteriskNOW distro

Available as install or live CD, VMWare & Xen

Asterisk installed and running when booted

Asterisk v1.4 now has a web GUI

Many good resources exist to get you started

Not to mention it now has ADHEARSION

Installing Adhearsion gem install adhearsion [asterisk-context] exten => _.,1,AGI(agi://127.0.0.1)

Writing Adhearsion Dialplans internal { }

Writing Adhearsion Dialplans internal { play ‘hello-world’ }

Writing Adhearsion Dialplans internal { loop { play ‘tt-monkeys’ } }

Writing Adhearsion Dialplans internal { +foo } foo { record { dial SIP/:out_trunk/1234 } }

Writing Adhearsion Dialplans internal { play %w”a-connect-charge-of 16 cents-per-minute will-apply” }

Writing Adhearsion Dialplans internal { case extension when 10 ... 100 dial SIP /extension when 6000 ... 6020 , 7000 .. 7030 join extension when _ ' 21XX ' if Time .now.hour.between? 2 , 10 dial SIP / " berlin-office " /extension[ 2 .. 4 ] else speak " It is not business hours now in Germany. " end ...

Writing Adhearsion Dialplans ... when US_NUMBER dial SIP / ' us-trunk-out ' /extension when / ^ d {11,}$ / dial IAX / ' intl-trunk-out ' /extension else play %w' sorry invalid extension please-try-again ' end }

Database-Driven Dialplans Dialplans service { customer = Account.find_by_phone_number callerid usage = customer.usage_this_month if usage >= 100.hours then +beyond_limit else customer.usage_this_month += time do dial IAX2/'main-trunk'/extension end end } beyond_limit { play %w"sorry your-limit-of 100 hours has-been-reached" }

How Does Adhearsion Talk to Asterisk?

Asterisk receives a call normally

Asterisk establishes a socket to Adhearsion, sending all call-related information

Adhearsion evaluates its own dial plan and sends commands over one at a time using AGI

Asterisk evals commands one at a time, sending a result after each

Dialog continues until call ends

Things you can do from Rails

Invoke virtually any PBX event with Adhearsion’s sexy syntaxes

Start calls, view live channels, record channel

Share Adhearsion’s ActiveRecord models

Manage users, groups, anything...

Manage a DB-driven dial plan

Use your imagination!

Helpers

What’s a Helper?

Code loaded when Adhearsion boots

Introduces a technology to the framework

Can be virtually anything

Can be written in Ruby, C, Java (JRuby)

Helpers require "hpricot" require "open-uri" def lookup number hash = {} url = " http://www.whitepages.com/9901/search/ReversePhone?phone=#{number} " doc = Hpricot open(url) # This div contains all the information we need, unless it's an unlisted number if (results = doc.at "#results_single_listing") then # This div's h3 contains the name of the caller hash[:first_name], hash[:last_name] = results.at('h3').inner_html.split(/,s*/).reverse # Now we just need the rest of the information contained in p's. meta = results/'p' meta.pop # Discard the useless p element hash[:number] = meta.pop.inner_html city_info = meta.pop.inner_html city_info = city_info.match /(.+), ([A-Za-z]{2}) (d{5})/ hash[:city] = city_info[1] hash[:state] = city_info[2] hash[:zip] = city_info[3] hash[:address] = meta.map(&:inner_html) * " " elsif (results = doc.at "#results_single_phone_info") then meta = results/'span' hash[:location] = (meta.pop.inner_html.match /Location: (.*)/)[1] end if hash[:first_name] or hash[:last_name] then hash[:composite] = "#{hash[:first_name]} #{hash[:last_name]}" else hash[:composite] = hash[:location] end hash end

Helpers (in C) (in C) int fast_factorial(int input) { int prod = 1, count = 1; while(count <= input) { prod *= count++; } return sum; }

Micromenus

Many modern IP phones have micro-browsers

Use custom XML schema over HTTP

Uses a Ruby DSL to generate

Mini-web app framework

Also viewable in a web browser!

Micromenus item 'Adhearsion Server Statistics' do item 'View Registered SIP Users' do PBX.sip_users.each do |u| item "SIP user '#{u.username}' on IP #{u.ip}" end end item 'View System Uptime' do item `uptime` end item 'Network' do heading 'Network Interface Info' `ifconfig eth1`.each_line do |line| item line end end end

Micromenus item 'Call an Employee' do item 'Select an employee below.' User.find(:all).each do |user| call user.extension, user.name end end call 'Join main conference' do play 'welcome' join 5555 end

Where Adhearsion is Headed is Headed