vpopmail

[Eric Broch]

On 10/4/2018 7:27 AM, Rick Romero wrote:
>
> Quoting Eric Broch <ebroch at whitehorsetc.com 
> <mailto:ebroch at whitehorsetc.com>>:
>
>>
>> On 10/4/2018 6:34 AM, Rick Romero wrote:
>>>
> Quoting Aki Tuomi <aki.tuomi at open-xchange.com 
> <mailto:aki.tuomi at open-xchange.com>>:
>
>> On 03.10.2018 23:30, Eric Broch wrote:
>>
>>> Hello list,
>>>
>>> I run Dovecot with the vpopmail driver and have found that it
>>> authenticates against the clear text password in the vpopmail
>>> database. Is there a configuration option either at compile time, link
>>> time, or a setting in one of the configuration files that tells the
>>> program to authenticate against the hash instead of the clear text?
>>>
>> Prefix your passwords in vpopmail with {SCHEME} (like,  {CRYPT})
>> Aki
>
>
> Or use SQL -  then you don't have to munge any of your tools.
>
> password_query =
> SELECT CONCAT(pw_name, '@', pw_domain) AS user, pw_passwd AS password, 
> pw_dir as userdb_home, 89 as userdb_uid, 89 as userdb_gid
> FROM vpopmail WHERE pw_name = '%n' AND pw_domain = '%d' AND !(pw_gid & 
> 8) AND !(pw_gid & 2) AND ('%r'!='<webserverip>' or !(pw_gid & 4))
>
> pw_gid refers to the the binary vpopmail flags for disable POP, IMAP, 
> Webmail.
>
> Rick
>
Rick,

I'm not sure what you're saying.

Vpopmail's DB can be configured in two different ways, 1) With domain 
tables and all users for that particular domain underneath (described 
below), or 2) Simply, one table with all users with the domain field 
'pw_domain' (This works with dovecot-sql.conf.ext files). The former 
(1), which we use does not allow the use of dovecot-sql.conf.ext files, 
we're limited to userdb and passwd options previously mentioned. When 
using these options dovecot will get the clear text password if present.

The problem is that if a password is over 16 characters long the clear 
text field will only store the first 16 characters while the hashed 
field will contain the whole password.

# echo "describe domain_tld" | mysql -u root -p`cat vpoppasswd` vpopmail
yeilds
Field   Type    Null    Key     Default Extra
pw_name char(32)        NO      PRI     NULL
pw_passwd       char(40)        YES             NULL
pw_uid  int(11) YES             NULL
pw_gid  int(11) YES             NULL
pw_gecos        char(48)        YES             NULL
pw_dir  char(160)       YES             NULL
pw_shell        char(20)        YES             NULL
pw_clear_passwd char(16)        YES             NULL

As you can see there is no 'pw_domain' field from which to draw.

Again we are limited to the passdb, and userdb options already described.


> When configuring vpopmail for our purposes we use (now) the 
> configuration option:
>
>   --disable-many-domains     Creates a table for each virtual domain instead of storing all users in a single table.
>                              Only valid for MySQL and PostgreSQL
>
> This disallows (I think) the use Dovecot MySQL configuration file as every user is stored in a domain table of the form 'mydomain_tld'.
>
> So, we're limited to these configurations (no dovecot-mysql.conf.ext) :
>
> passdb {
>    args = cache_key=%u webmail=127.0.0.1
>    driver = vpopmail
> }
>
> userdb {
>    args = cache_key=%u quota_template=quota_rule=*:backend=%q
>    driver = vpopmail
> }
>
> If there is a clear text password (pw_clear_passwd) present it seems that Dovecot will use that instead of using the hash (pw_passwd).
>
> It seems that in the code 'passdb-vpopmail.c' (below) that if the clear password (pw_clear_passwd) is present Dovecot skips the hashed password (pw_passwd), and we want authentication against the hashed password.
>
> <snippet>
>          if (vpopmail_is_disabled(auth_request, vpw)) {
>                  auth_request_log_info(auth_request, AUTH_SUBSYS_DB,
>                                        "%s disabled in vpopmail for this user",
>                                        auth_request->service);
>                  password = NULL;
>                  *result_r = PASSDB_RESULT_USER_DISABLED;
>          } else {
>                  if (vpw->pw_clear_passwd != NULL &&
>                      *vpw->pw_clear_passwd != '\0') {
>                          password = t_strdup_noconst(vpw->pw_clear_passwd);
>                          *cleartext = TRUE;
>                  } else if (!*cleartext)
>                          password = t_strdup_noconst(vpw->pw_passwd);
>                  else
>                          password = NULL;
>                  *result_r = password != NULL ? PASSDB_RESULT_OK :
>                          PASSDB_RESULT_SCHEME_NOT_AVAILABLE;
>          }
> </snippet>
>
>
> Looking for an option to make dovecot use hashed password instead of clear text.
>
> Hope this makes sense.
>
> -EricB
>
> We seem to have lost quoting..
> First - Why aren't you just deleting all the clear text passwords?
>
> Second, for many domanis, my password query for your purposes should just be:
> SELECT CONCAT(pw_name, '@', pw_domain) AS user, pw_passwd AS password, pw_dir as userdb_home, 89 as userdb_uid, 89 as userdb_gid
> FROM %d WHERE pw_name = '%n' AND pw_domain = '%d' AND !(pw_gid & 8) AND !(pw_gid & 2) AND ('%r'!='<webserverip>' or !(pw_gid & 4))
>
> Where %d is the domain name. Your vpopmail database should have a bunch of domain.com table names.
> Or you can hardcode the database with   FROM vpopmail.%d
> You may need to play with quotes..  FROM `vpopmail.%d`  or  FROM `%d`
>
> Rick

-- 
Eric Broch
White Horse Technical Consulting (WHTC)

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