DOKK / manpages / debian 12 / opensmtpd-extras / table-sqlite.5.en
TABLE_SQLITE(5) File Formats Manual TABLE_SQLITE(5)

table_sqliteformat description for smtpd sqlite tables

This manual page documents the file format of sqlite tables used by the smtpd(8) mail daemon.

The format described here applies to tables as defined in smtpd.conf(5).

A sqlite table allows the storing of usernames, passwords, aliases, and domains in a format that is shareable across various machines that support sqlite3(1) (SQLite version 3).

The table is used by smtpd(8) when authenticating a user, when user information such as user-id and/or home directory is required for a delivery, when a domain lookup may be required, and/or when looking for an alias.

A sqlite table consists of one or more sqlite3(1) databases with one or more tables.

If the table is used for authentication, the password should be encrypted using the crypt(3) function. Such passwords can be generated using the encrypt(1) utility or smtpctl(8) encrypt command.

The following configuration options are available:

file
This is the path to where the DB file is located. For example:
dbpath /etc/mail/smtp.sqlite
SQL statement
This is used to provide a query to look up aliases. The question mark is replaced with the appropriate data. For alias it is the left hand side of the SMTP address. This expects one VARCHAR to be returned with the user name the alias resolves to.
SQL statement
This is used to provide a query for looking up user credentials. The question mark is replaced with the appropriate data. For credentials it is the left hand side of the SMTP address. The query expects that there are two VARCHARS returned, one with a user name and one with a password in crypt(3) format.
SQL statement
This is used to provide a query for looking up a domain. The question mark is replaced with the appropriate data. For the domain it would be the right hand side of the SMTP address. This expects one VARCHAR to be returned with a matching domain name.
SQL statement
This is used to provide a query for looking up a senders. The question mark is replaced with the appropriate data. This expects one VARCHAR to be returned with the address the sender is allowed to send mails from.
A generic SQL statement would be something like:
query_ SELECT value FROM table WHERE key=?;

Example based on the OpenSMTPD FAQ: Building a Mail Server The filtering part is excluded in this example. The configuration below is for a medium-size mail server which handles multiple domains with multiple virtual users and is based on several assumptions. One is that a single system user named vmail is used for all virtual users. This user needs to be created:

# useradd -g =uid -c "Virtual Mail" -d /var/vmail -s /sbin/nologin vmail
# mkdir /var/vmail
# chown vmail:vmail /var/vmail
sqlite schema
CREATE TABLE virtuals (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    email VARCHAR(255) NOT NULL,
    destination VARCHAR(255) NOT NULL
);
CREATE TABLE credentials (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    email VARCHAR(255) NOT NULL,
    password VARCHAR(255) NOT NULL
);
CREATE TABLE domains (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    domain VARCHAR(255) NOT NULL
);
INSERT INTO domains VALUES (1, "example.com");
INSERT INTO domains VALUES (2, "example.net");
INSERT INTO domains VALUES (3, "example.org");
INSERT INTO virtuals VALUES (1, "abuse@example.com", "bob@example.com");
INSERT INTO virtuals VALUES (2, "postmaster@example.com", "bob@example.com");
INSERT INTO virtuals VALUES (3, "webmaster@example.com", "bob@example.com");
INSERT INTO virtuals VALUES (4, "bob@example.com", "vmail");
INSERT INTO virtuals VALUES (5, "abuse@example.net", "alice@example.net");
INSERT INTO virtuals VALUES (6, "postmaster@example.net", "alice@example.net");
INSERT INTO virtuals VALUES (7, "webmaster@example.net", "alice@example.net");
INSERT INTO virtuals VALUES (8, "alice@example.net", "vmail");
INSERT INTO credentials VALUES (1, "bob@example.com", "$2b$08$ANGFKBL.BnDLL0bUl7I6aumTCLRJSQluSQLuueWRG.xceworWrUIu");
INSERT INTO credentials VALUES (2, "alice@example.net", "$2b$08$AkHdB37kaj2NEoTcISHSYOCEBA5vyW1RcD8H1HG.XX0P/G1KIYwii");
/etc/mail/sqlite.conf
dbpath /etc/mail/smtp.sqlite
query_alias SELECT destination FROM virtuals WHERE email=?;
query_credentials SELECT email, password FROM credentials WHERE email=?;
query_domain SELECT domain FROM domains WHERE domain=?;
/etc/mail/smtpd.conf
table domains sqlite:/etc/mail/sqlite.conf
table virtuals sqlite:/etc/mail/sqlite.conf
table credentials sqlite:/etc/mail/sqlite.conf
listen on egress port 25 tls pki mail.example.com
listen on egress port 587 tls-require pki mail.example.com auth <credentials>
accept from any for domain <domains> virtual <virtuals> deliver to mbox

/etc/mail/sqlite.conf
Default table-sqlite(8) configuration file.
/etc/mail/smtp.sqlite
Suggested sqlite3(1) database file.

Documenting the following query options:

query_netaddr
query_userinfo
query_source
query_mailaddr
query_addrname

smtpd.conf(5), smtpctl(8), smtpd(8), encrypt(1), crypt(3)

July 4, 2016 Debian