Re: [Dovecot] Accessing plain text password from memory
Hi Timo,
thanks for the answer. I'm working on a plug in with an similar
architecture.
Is there also a way to pass that plain password to a mail filter script?
Obviously, the %w option as mail filter script argument does not work.
Kind regards,
Philipp
On 13/12/13 15:47, Timo Sirainen wrote:
On 13.12.2013, at 16.37, Stanislas SABATIER wrote:
Is there a way to retrieve the client's password in plain text from memory ?
I don't store the password in plain text in my postgreSQL but I need it
when the client is connected to make crypto computation.
If I write a plugin to do the job, how could I retrieve the plain text
password from master ?
Assuming you you're using passdb sql and userdb prefetch and you want to access
the password in imap/pop3/etc process, you can do:
password_query = '%w' as userdb_password, ...
Then the password will be available the same way as plugin { password } would
be available (mail_user_plugin_getenv()).
You could also write a passdb plugin you could access the password directly from
auth_request->mech_password.
smime.p7s
Description: S/MIME Cryptographic Signature
Re: [Dovecot] Accessing plain text password from memory
Thanks for the info, I'll dig this option.
Regards,
Stan.
Le 13 déc. 2013 à 15:47, Timo Sirainen a écrit :
> On 13.12.2013, at 16.37, Stanislas SABATIER wrote:
>
>> Is there a way to retrieve the client's password in plain text from memory ?
>>
>> I don't store the password in plain text in my postgreSQL but I need it
>> when the client is connected to make crypto computation.
>>
>> If I write a plugin to do the job, how could I retrieve the plain text
>> password from master ?
>
> Assuming you you're using passdb sql and userdb prefetch and you want to
> access the password in imap/pop3/etc process, you can do:
>
> password_query = '%w' as userdb_password, ...
>
> Then the password will be available the same way as plugin { password } would
> be available (mail_user_plugin_getenv()).
>
> You could also write a passdb plugin you could access the password directly
> from auth_request->mech_password.
>
Re: [Dovecot] Accessing plain text password from memory
Quoting Stanislas SABATIER : 2013/12/13 Rick Romero (…) IMHO, your time is better spent creating a PGP plugin that uses public keys to encrypt the email contents. Rick That's exactly what I'm doing. Inbound mails are all encrypted with each client's public key. Then, clients can either decrypt mails on their own personal computer, or have their mails decrypted on-the-fly server side. In the later case, I store an encrypted private key for each client. To open the private key, I need client's password. Stan Oh! I feel so much better now :) Rick
Re: [Dovecot] Accessing plain text password from memory
2013/12/13 Rick Romero > > (…) > > IMHO, your time is better spent creating a PGP plugin that uses public > keys to encrypt the email contents. > Rick > > > > That's exactly what I'm doing. Inbound mails are all encrypted with each client's public key. Then, clients can either decrypt mails on their own personal computer, or have their mails decrypted on-the-fly server side. In the later case, I store an encrypted private key for each client. To open the private key, I need client's password. Stan
Re: [Dovecot] Accessing plain text password from memory
As long as you're not claiming that you can't access the data, then I won't get uppity :) Though I honestly don't see any advantage to the approach you're taking. It was useless for Lavabit, it's a poor method that's not going to fair any better under anyone else's watch. Why not just zip all the files up and rename the extension? That'll be 'difficult' to defeat too, and the plugins already exist. A rogue agent with local access will be able to access the mailboxes, encrypted or not. Are you running a FAM? Centralized SIEM? If not, they just set the debug flag and reload the service without you ever even knowing. IMHO, your time is better spent creating a PGP plugin that uses public keys to encrypt the email contents. Of course you lose indexing and searches.. It's just _not_ going to be secure if a local service can decrypt the data. I agree the core problem is SMTP. I'd be willing to use a new email protocol as well, but I don't have high hopes from 'that' group. It's like they've got Einstein and PT Barnum... Rick Quoting Stanislas SABATIER : Hi rick, I DO want to encrypt/decrypt mails on the fly without «lying » to my customers. It's better to have encrypted mail that are difficult to decrypt than plain text files within plain text folders. (Yes, it would be possible to get the user password on the fly, but my system is not design this way) I agree that it's not panacea, but it's better than no encryption at all. Isn't it ? As soon as a new email protocol will be available, I'll be the first to switch to it ! Regards, Stan. --- Stanislas SABATIER s.sabat...@pobox.com --- 2013/12/13 Stanislas SABATIER Is there a way to retrieve the client's password in plain text from memory ? I don't store the password in plain text in my postgreSQL but I need it when the client is connected to make crypto computation. If I write a plugin to do the job, how could I retrieve the plain text password from master ? Thank you for your help, Regards, Stan. --- Stanislas SABATIER s.sabat...@pobox.com ---
Re: [Dovecot] Accessing plain text password from memory
Hi rick, I DO want to encrypt/decrypt mails on the fly without «lying » to my customers. It's better to have encrypted mail that are difficult to decrypt than plain text files within plain text folders. (Yes, it would be possible to get the user password on the fly, but my system is not design this way) I agree that it's not panacea, but it's better than no encryption at all. Isn't it ? As soon as a new email protocol will be available, I'll be the first to switch to it ! Regards, Stan. --- Stanislas SABATIER s.sabat...@pobox.com --- 2013/12/13 Stanislas SABATIER > Is there a way to retrieve the client's password in plain text from memory > ? > > I don't store the password in plain text in my postgreSQL but I need it > when the client is connected to make crypto computation. > > If I write a plugin to do the job, how could I retrieve the plain text > password from master ? > > Thank you for your help, > > Regards, > Stan. > > --- > Stanislas SABATIER > s.sabat...@pobox.com > --- > >
Re: [Dovecot] Accessing plain text password from memory
Quoting Stanislas SABATIER : Is there a way to retrieve the client's password in plain text from memory ? I don't store the password in plain text in my postgreSQL but I need it when the client is connected to make crypto computation. Hi Stan, I hope you're not trying to copy Lavabit. Saying you don't have access to mailbox contents on your own equipment would be a flat out lie. 1. You have the password in memory. Simply set the debug flags and you can retrieve the password, as Lavabit did, to decrypt the mailbox. Their claim of 'our policy is not to run in debug mode, therefore we can't access your data' is not actually a form of security. 2. SMTP is in plain text. After the existing mail is read, any incoming or outgoing mail is easily CC'd to a 'monitoring' mailbox based on SMTP Auth or RCPT TO. If it's not mailbox encryption, sorry (you have no idea how much I detest that Lavabit guy for his lies), but if it is then it's nothing more than a programming exercise. Rick
Re: [Dovecot] Accessing plain text password from memory
On 13.12.2013, at 16.37, Stanislas SABATIER wrote:
> Is there a way to retrieve the client's password in plain text from memory ?
>
> I don't store the password in plain text in my postgreSQL but I need it
> when the client is connected to make crypto computation.
>
> If I write a plugin to do the job, how could I retrieve the plain text
> password from master ?
Assuming you you're using passdb sql and userdb prefetch and you want to access
the password in imap/pop3/etc process, you can do:
password_query = '%w' as userdb_password, ...
Then the password will be available the same way as plugin { password } would
be available (mail_user_plugin_getenv()).
You could also write a passdb plugin you could access the password directly
from auth_request->mech_password.
Re: [Dovecot] Accessing plain text password from memory
On 2013-12-13 15:37, Stanislas SABATIER wrote: Is there a way to retrieve the client's password in plain text from memory ? I don't store the password in plain text in my postgreSQL but I need it when the client is connected to make crypto computation. If I write a plugin to do the job, how could I retrieve the plain text password from master ? Thank you for your help, Regards, Stan. --- Stanislas SABATIER s.sabat...@pobox.com --- If you enable auth_debug you can also enable auth_debug_passwords and that will show the plaintext password in the logfile when the user connects. I can't say I would recommend it though. /A
[Dovecot] Accessing plain text password from memory
Is there a way to retrieve the client's password in plain text from memory ? I don't store the password in plain text in my postgreSQL but I need it when the client is connected to make crypto computation. If I write a plugin to do the job, how could I retrieve the plain text password from master ? Thank you for your help, Regards, Stan. --- Stanislas SABATIER s.sabat...@pobox.com ---
