- Pharo-users - lists.pharo.org

FUEL documentation

by Juraj Kubelka

(sorry, I have accidentally pressed send button) Hi, Is there any documentation about FUEL? I would like to understand in more detail what data are serialized, if I can somehow alter it (filter it) explicitly, and how can I handle errors on materialization. I was playing a bit with it and in some case, during the materialization, it complained that there is a missing class, but I was pretty sure that the class has nothing to do with the serialized objects. So, I will appreciate any documentation that helps to understand how I can analyze what is serialized and how to handle materialization errors. Thanks! Juraj

June 30, 2017

FUEL documentation

by Juraj Kubelka

Hi, Is there any documentation about FUEL? I would like to understand in more detail what data -- Juraj Kubelka

June 30, 2017

Re: [Pharo-users] Validate password with PBKDF2

by Erik Stel

Francis, You're using an empty salt when creating the hash. Just prepending a random number does not add much security. Anyone knowing your solution will just prepend a random number. And creating only a few accounts in your system will probably reveal that information as well. A wrong-doer will just use a fake salt and will still be able to try a rainbow table attack. Please use a real random value for the salt. And easiest would be to give it a fixed size. (Don't have an image and/or code available, so this might lead to some pseudo code ;-) To generate a safe password hash which you can store in your db, the following method. It creates a random number (your example of a UUID of 16 bytes) and uses that as a salt for the password hash. Both values are then concatenated and returned as a 'safe' password. This can be stored in your db. To validate a user's password you retrieve the safePasswordHash from your db (based on the user's id) and validate the given password against it. For this the salt is retrieved from the safePasswordHash (first 16 bytes because UUID is 16 bytes) and it is then used to calculate the hash of the given password. It should match the second part of the safePasswordHash. Hope this helps. For real safety, please add some checks for valid values. Did we receive a valid password? Is the safePasswordHash the correct length (in this case 32 bytes)? You might consider using another salt generator than UUID. Cheers, Erik -- View this message in context: http://forum.world.st/Validate-password-with-PBKDF2-tp4952973p4953129.html Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

June 30, 2017

Re: [Pharo-users] [ANN] An evening with Pharo and the ESP32 microcontroller

by Ben Coman

On Fri, Jun 30, 2017 at 9:50 PM, Georges <gkgobith(a)gmail.com> wrote: > Cool stuff Ben! :) > > I dusted of my Arduino Uno and tried out reading the Serial Port using your > tutorial. > It would be nice for a follow up tutorial to write to the board and switch > the builtin led on/off ! > > Georges > Glad you liked it. Actually, I thought I might append to that article a section "Lets actually do something useful" to do that, and also read an analog input. The next article will be testing bulk analog data read over TCPIP WiFi connection. cheers -ben

June 30, 2017

Re: Validate password with PBKDF2

by Francis

Thanks Pierce and hernanmd I decided to adopt the solution of the prepended salt as Erik said in the previous post. Here is my code, I hope it can be useful for the community First I hash the password with an empty salt PBKDF2 derivedKeyHashFunction: SHA256 password: 'aSimplePassword' salt: '' iterations: 3000 length: 16 . I would have liked to avoid the empty salt but the message deriveKey needs it. Then I used UUID new as real salt and the string '$$' as separator between the salt and the hashed password. So here is the byte array I'm going to store in my db saltPlusHashedPassword := UUID new , '$$' asByteArray , (PBKDF2 derivedKeyHashFunction: SHA256 password: 'aSimplePassword' salt: '' iterations: 3000 length: 16 ). To validate the password, I retrieve the saltPlusHashedPassword from the db and splitting it hashedPassword := (saltPlusHashedPassword splitOn:('$$' asByteArray)) second. Finally the validation (PBKDF2 derivedKeyHashFunction: SHA256 password: 'aSimplePassword' salt: '' iterations: 3000 length: 16 ) = (ByteArray new, hashedPassword). Note, I have to concatenate ByteArray new with hashedPassword because hashedPassword is not a ByteAttay but a UUID, if you have a smarter way to do it you are welcome. HTH Francis Erik Stel wrote > Francis, > > The hashpw function returns a hash with the salt prepended. So it contains > both elements. (See for example explanation at: > https://stackoverflow.com/questions/27413248/why-can-bcrypt-hashpw-be-used-…) > > You can do the same thing here. Assuming you have a fixed size salt, just > prepend it before the hash value. Since the salt is (should be) random, > returning it's value does not weaken the security. Using a salt prevents > against rainbow table attacks: pre-generated hash values for many possible > passwords. (See https://en.wikipedia.org/wiki/Rainbow_table) > > Cheers, > Erik -- View this message in context: http://forum.world.st/Validate-password-with-PBKDF2-tp4952973p4953119.html Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

June 30, 2017

Re: [Pharo-users] [ANN] An evening with Pharo and the ESP32 microcontroller

by Georges

Cool stuff Ben! :) I dusted of my Arduino Uno and tried out reading the Serial Port using your tutorial. It would be nice for a follow up tutorial to write to the board and switch the builtin led on/off ! Georges -- View this message in context: http://forum.world.st/ANN-An-evening-with-Pharo-and-the-ESP32-microcontroll… Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

June 30, 2017

Re: [Pharo-users] Validate password with PBKDF2

by HernÃ¡n Morales Durand

I guess I could integrate Udo's PBKDF2 into ApplicationSecurity. See under "Using the CheckPoint" if matches your API you're looking for: http://80738163270632.blogspot.com.ar/2014/10/application-security-2-checkp… Cheers, HernÃ¡n 2017-06-30 4:43 GMT-03:00 Francis via Pharo-users < pharo-users(a)lists.pharo.org>: > > > ---------- Mensaje reenviado ---------- > From: Francis <falzonidavide(a)libero.it> > To: pharo-users(a)lists.pharo.org > Cc: > Bcc: > Date: Fri, 30 Jun 2017 00:43:23 -0700 (PDT) > Subject: Re: Validate password with PBKDF2 > Thank you Paul, > Saving the salt is not a big issue but I'd like something more simple. > In python I can store the salt with the password > see:https://pypi.python.org/pypi/bcrypt/3.1.0 > > # Hash a password for the first time, with a randomly-generated salt > hashed = bcrypt.hashpw(password, bcrypt.gensalt()) > > and retrieve it subsequently > if bcrypt.checkpw(password, hashed): > ... print("It Matches!") > > Are you (smalltalkers) aware of something similar? > > Thanks again > Francis > > > > Paul DeBruicker wrote > > Looks like you'll have to store the salt when making the original hash of > > the password. > > > > With that you can do > > > > > > | salt originalPassword userInputPassword originalHash newHash secretKey > > | > > salt:='salt'. > > originalPassword:='password'. > > userInputPassword:='12345678'. > > originalHash:=PBKDF2 derivedKeySHA1Password: originalPassword salt: salt. > > newHash:=PBKDF2 derivedKeySHA1Password: userInputPassword salt: salt. > > > > secretKey:= SecureRandom new nextBytes: 16. > > > > ((SHA256 new hmac key: secretKey) digestMessage: originalHash) = ((SHA256 > > new hmac key: secretKey) digestMessage: newHash). > > > > > > > > We do the double SHA256 HMAC signing of the hashes because of > > https://www.nccgroup.trust/us/about-us/newsroom-and-events/ > blog/2011/february/double-hmac-verification/ > > > > You can store the #secretKey and each user should get a new #salt every > > time they change their password and you shouldn't reuse the salts for > > other users or password. > > > > For PBKDF2 there is probably a max (or recommended) salt length but I > > don't know it. > > > > I also don't know anything about the SecureRandom class but it says it on > > the tin, so maybe it is. Maybe not though. I don't know how to find > out. > > But I don't know that it matters in this instance as its only used for > the > > SHA256 HMAC internally in the comparison function. > > > > > > Hope this helps. > > > > > > Francis wrote > >> Hi folks > >> > >> I'm playing with the PBKDF2 package of Udo: > >> http://www.smalltalkhub.com/#!/~UdoSchneider/PBKDF2 > >> (thanks Udo), but I can't find how to validate a stored hash. > >> Can you point me in the right direction? > >> > >> Thanks > >> Francis > > > > > > -- > View this message in context: http://forum.world.st/ > Validate-password-with-PBKDF2-tp4952973p4953004.html > Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com. > > >

June 30, 2017

Re: [Pharo-users] Are we able to run pharo images in a read only environment?

by Sven Van Caekenberghe

> On 27 Jun 2017, at 21:15, Sven Van Caekenberghe <sven(a)stfx.eu> wrote: > > >> On 27 Jun 2017, at 21:00, Esteban A. Maringolo <emaringolo(a)gmail.com> wrote: >> >> Interesting experiment. >> >> It would be good to know how fast does the image boot and start >> execution in the context of a service billed at the sub second scale. > > Sadly I have the impression we lost some speed: > > ~/pharo64$ ./pharo Pharo.image printVersion > [version] 6.0 #60499 > > ~/pharo64$ time ./pharo Pharo.image eval '42 factorial' > 1405006117752879898543142606244511569936384000000000 > > real 0m1.276s > user 0m0.985s > sys 0m0.171s > > while before > > ~/pharo/build$ ../bin/pharo Pharo.image printVersion > [version] 4.0 #40620 > > $ time ../bin/pharo Pharo.image eval '42 factorial' > 1405006117752879898543142606244511569936384000000000 > > real 0m0.526s > user 0m0.434s > sys 0m0.045s > > But it is really hard to find the cause. The good news is that the Pharo 7 minimal core is way faster $ time ./pharo ~/Downloads/Pharo7.0-core-32bit-b649ac6.image eval "42 factorial" 1405006117752879898543142606244511569936384000000000 real 0m0.262s user 0m0.132s sys 0m0.062s Which is good of course ! > That being said, these lambda servers can only work well if they keep instances alive for longer when there is enough traffic. > >> Esteban A. Maringolo >> >> >> 2017-06-27 13:05 GMT-03:00 Tim Mackinnon <tim(a)testit.works>: >>> Hi - I am trying to run a pharo image in lambda (as an experiment) - however >>> I get an error from Pharo about not being able to write to the changes file? >>> >>> As I am just evaluating some code - Iâm not really coding, so donât need a >>> changes file - is there a command line option to not require it? >>> >>> Also, am I running pharo the most efficient way - Iâm using eval on the >>> command line and referencing a class with a class method - but is this the >>> best way? >>> >>> Thanks, >>> >>> Tim >>> >>> "errorMessage": "Command failed: ./pharo Pharo.image eval \"Lambda >>> processJSON: >>> '{\"key3\":\"value3\",\"key2\":\"value2\",\"key1\":\"value1\"}'\"\n'Pharo >>> cannot write to the changes file named /var/task/Pharo.changes.\n\nPlease >>> check that you have write permission for this file.\n\nYou won''t be able to >>> save this image correctly until you fix this.'\n\u001b[31mError: Can't find >>> the requested >>> origin\n\u001b[0mUnixResolver(PlatformResolver)>>cantFindOriginError\n[ self >>> cantFindOriginError ] in >>> UnixResolver(PlatformResolver)>>directoryFromEnvVariableNamed: in Block: [ >>> self cantFindOriginError >>> ]\nUnixResolver(PlatformResolver)>>directoryFromEnvVariableNamed:or:\nUnixResolver(PlatformResolver)>>directoryFromEnvVariableNamed:\nUnixResolver>>home\n[ >>> self home / '.config' ] in UnixResolver>>preferences in Block: [ self home / >>> '.config' >>> ]\nUnixResolver(PlatformResolver)>>directoryFromEnvVariableNamed:or:\nUnixResolver>>preferences\nUnixResolver(FileSystemResolver)>>resolve:\nSystemResolver(FileSystemResolver)>>unknownOrigin:\nSystemResolver(FileSystemResolver)>>resolve:\nInteractiveResolver>>unknownOrigin:\n[ >>> self unknownOrigin: origin ] in InteractiveResolver>>resolve: in Block: [ >>> self unknownOrigin: origin >>> ]\nIdentityDictionary(Dictionary)>>at:ifAbsent:\nInteractiveResolver>>resolve:\nFileLocator>>resolve\nFileLocator(AbstractFileReference)>>exists\nGlobalIdentifierStonPersistence(GlobalIdentifierPersistence)>>shouldCallPreviousPersistence\nGlobalIdentifierStonPersistence(GlobalIdentifierPersistence)>>ensure:\nGlobalIdentifier>>ensure\nGlobalIdentifier >>> class>>initializeUniqueInstance\nGlobalIdentifier >>> class>>uniqueInstance\nSystemSettingsPersistence >>> class>>resumeSystemSettings\n[ :persistence | persistence >>> resumeSystemSettings ] in PharoCommandLineHandler>>runPreferences in Block: >>> [ :persistence | persistence resumeSystemSettings >>> ...etc...\nBlockClosure>>cull:\nSystemDictionary(Dictionary)>>at:ifPresent:\nSmalltalkImage>>at:ifPresent:\nPharoCommandLineHandler>>runPreferences\nPharoCommandLineHandler>>activate\nPharoCommandLineHandler >>> class(CommandLineHandler class)>>activateWith:\n\u001b[0m", >>> "errorType": "Error", >>> "stackTrace": [ >>> "'Pharo cannot write to the changes file named >>> /var/task/Pharo.changes.", >>> "", >>> "Please check that you have write permission for this file.", >>> "", >>> "You won''t be able to save this image correctly until you fix this.'", >>> "\u001b[31mError: Can't find the requested origin", >>> "\u001b[0mUnixResolver(PlatformResolver)>>cantFindOriginError", >>> "[ self cantFindOriginError ] in >>> UnixResolver(PlatformResolver)>>directoryFromEnvVariableNamed: in Block: [ >>> self cantFindOriginError ]", >>> "UnixResolver(PlatformResolver)>>directoryFromEnvVariableNamed:or:", >>> "UnixResolver(PlatformResolver)>>directoryFromEnvVariableNamed:", >>> "UnixResolver>>home", >>> "[ self home / '.config' ] in UnixResolver>>preferences in Block: [ self >>> home / '.config' ]", >>> "UnixResolver(PlatformResolver)>>directoryFromEnvVariableNamed:or:", >>> "UnixResolver>>preferences", >>> "UnixResolver(FileSystemResolver)>>resolve:", >>> "SystemResolver(FileSystemResolver)>>unknownOrigin:", >>> "SystemResolver(FileSystemResolver)>>resolve:", >>> "InteractiveResolver>>unknownOrigin:", >>> "[ self unknownOrigin: origin ] in InteractiveResolver>>resolve: in >>> Block: [ self unknownOrigin: origin ]", >>> "IdentityDictionary(Dictionary)>>at:ifAbsent:", >>> "InteractiveResolver>>resolve:", >>> "FileLocator>>resolve", >>> "FileLocator(AbstractFileReference)>>exists", >>> >>> "GlobalIdentifierStonPersistence(GlobalIdentifierPersistence)>>shouldCallPreviousPersistence", >>> "GlobalIdentifierStonPersistence(GlobalIdentifierPersistence)>>ensure:", >>> "GlobalIdentifier>>ensure", >>> "GlobalIdentifier class>>initializeUniqueInstance", >>> "GlobalIdentifier class>>uniqueInstance", >>> "SystemSettingsPersistence class>>resumeSystemSettings", >>> "[ :persistence | persistence resumeSystemSettings ] in >>> PharoCommandLineHandler>>runPreferences in Block: [ :persistence | >>> persistence resumeSystemSettings ...etc...", >>> "BlockClosure>>cull:", >>> "SystemDictionary(Dictionary)>>at:ifPresent:", >>> "SmalltalkImage>>at:ifPresent:", >>> "PharoCommandLineHandler>>runPreferences", >>> "PharoCommandLineHandler>>activate", >>> "PharoCommandLineHandler class(CommandLineHandler >>> class)>>activateWith:", >>> "\u001b[0m", >>> "ChildProcess.exithandler (child_process.js:204:12)", >>> "emitTwo (events.js:106:13)", >>> "ChildProcess.emit (events.js:191:7)", >>> "maybeClose (internal/child_process.js:886:16)", >>> "Process.ChildProcess._handle.onexit (internal/child_process.js:226:5)" >>> ] >>> } >>> >>> >> >

June 30, 2017

Re: [Pharo-users] Validate password with PBKDF2

by Erik Stel

Francis, The hashpw function returns a hash with the salt prepended. So it contains both elements. (See for example explanation at: https://stackoverflow.com/questions/27413248/why-can-bcrypt-hashpw-be-used-…) You can do the same thing here. Assuming you have a fixed size salt, just prepend it before the hash value. Since the salt is (should be) random, returning it's value does not weaken the security. Using a salt prevents against rainbow table attacks: pre-generated hash values for many possible passwords. (See https://en.wikipedia.org/wiki/Rainbow_table) Cheers, Erik -- View this message in context: http://forum.world.st/Validate-password-with-PBKDF2-tp4952973p4953067.html Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

June 30, 2017

Re: [Pharo-users] Logging in with VNC

by Pierce Ng

On Thu, Jun 29, 2017 at 08:59:18AM -0400, sergio ruiz wrote: > I need to be able to log in to my production image with VNC until i am > comfortable with the command line interface. I know that every time i have > had to do it, it seems like i used a different package. > > Which package is everyone using these days for remote GUI access? http://smalltalkhub.com/#!/~PharoExtras/RFB Tested working with X11 clients like Vinagre connecting to Pharo 5 in-image server. Pierce

June 30, 2017