Mercurial > gemma
view pkg/auth/opendb.go @ 4723:baabc2b2f094
Avoid creating user profiles without matching role
The INSTEAD OF triggers on users.list_users did that already, but
profile data coming e.g. via restoring a dump had been added also
if there was no matching database role in the cluster.
This also unifies the errors occuring on creation of users with existing
role names that differed between roles with and without profile before.
Note this is no referential integrity. A dropped role still leaves an
orphaned profile behind.
author | Tom Gottfried <tom@intevation.de> |
---|---|
date | Thu, 17 Oct 2019 18:56:59 +0200 |
parents | 7cccf7fef3e8 |
children | c64dba002726 |
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// This is Free Software under GNU Affero General Public License v >= 3.0 // without warranty, see README.md and license for details. // // SPDX-License-Identifier: AGPL-3.0-or-later // License-Filename: LICENSES/AGPL-3.0.txt // // Copyright (C) 2018 by via donau // – Österreichische Wasserstraßen-Gesellschaft mbH // Software engineering by Intevation GmbH // // Author(s): // * Sascha L. Teichmann <sascha.teichmann@intevation.de> package auth import ( "context" "database/sql" "errors" "net/http" "sync" "github.com/jackc/pgx" "github.com/jackc/pgx/stdlib" "gemma.intevation.de/gemma/pkg/config" ) var ( // ErrNoMetamorphUser is returned if no metamorphic user is configured. ErrNoMetamorphUser = errors.New("no metamorphic user configured") // ErrNotLoggedIn is returned if there is the user is not logged in. ErrNotLoggedIn = errors.New("not logged in") ) // OpenDB opens up a database connection with a given username and password. // The other credentials are taken from the configuration. func OpenDB(user, password string) (*sql.DB, error) { // To ease SSL config ride a bit on parsing. cc, err := pgx.ParseConnectionString("sslmode=" + config.DBSSLMode()) if err != nil { return nil, err } // Do the rest manually to allow whitespace in user/password. cc.Host = config.DBHost() cc.Port = uint16(config.DBPort()) cc.User = user cc.Password = password cc.Database = config.DBName() return stdlib.OpenDB(cc), nil } type metamorph struct { sync.Mutex db *sql.DB } var mm metamorph func (m *metamorph) open() (*sql.DB, error) { m.Lock() defer m.Unlock() if m.db != nil { return m.db, nil } user := config.DBUser() if user == "" { return nil, ErrNoMetamorphUser } db, err := OpenDB(user, config.DBPassword()) if err != nil { return nil, err } m.db = db return db, nil } func metamorphConn(ctx context.Context, user string) (*sql.Conn, error) { db, err := mm.open() if err != nil { return nil, err } conn, err := db.Conn(ctx) if err != nil { return nil, err } if _, err := conn.ExecContext(ctx, `SELECT public.setrole_plan($1)`, user); err != nil { conn.Close() return nil, err } return conn, nil } const allRoles = ` WITH RECURSIVE cte AS ( SELECT oid FROM pg_roles WHERE rolname = current_user UNION ALL SELECT m.roleid FROM cte JOIN pg_auth_members m ON m.member = cte.oid ) SELECT rolname FROM pg_roles WHERE oid IN (SELECT oid FROM cte) AND rolname <> current_user AND EXISTS (SELECT 1 FROM users.list_users WHERE username = current_user)` // AllOtherRoles loggs in as user with password and returns a list // of all roles the logged in user has in the system. func AllOtherRoles(user, password string) (Roles, error) { db, err := OpenDB(user, password) if err != nil { return nil, err } defer db.Close() rows, err := db.Query(allRoles) if err != nil { return nil, err } defer rows.Close() roles := Roles{} // explicit empty by intention. for rows.Next() { var role string if err := rows.Scan(&role); err != nil { return nil, err } roles = append(roles, role) } return roles, rows.Err() } // RunAs runs a given function fn with a database connection impersonated // as the given role. // To make this work a metamorphic user has to be configured in // the system configuration. func RunAs(ctx context.Context, role string, fn func(*sql.Conn) error) error { conn, err := metamorphConn(ctx, role) if err != nil { return err } defer conn.Close() return fn(conn) } // RunAsSessionUser is a convinience wrapper araound which extracts // the logged in user from a session and calls RunAs with it. func RunAsSessionUser(req *http.Request, fn func(*sql.Conn) error) error { token, ok := GetToken(req) if !ok { return ErrNotLoggedIn } session := Sessions.Session(token) if session == nil { return ErrNotLoggedIn } return RunAs(req.Context(), session.User, fn) }