verify.go

package main

// Copyright (C) 2013 Alexander Bauer, Luke Evers, Daniel Supernault,
// Dylan Whichard, and contributors; (GPLv3) see LICENSE or doc.go

import (
	"database/sql"
	"errors"
	"fmt"
	"math/rand"
	"net"
	"net/http"
	"time"
)

// QueueNode inserts the given node into the verify queue with its
// expiration time set to the current time plus the grace period, its
// emailsent field set by the matching argument, and identified by the
// given ID.
func (db DB) QueueNode(id int64, emailsent bool, grace Duration, node *Node) (err error) {
	_, err = db.Exec(`INSERT INTO nodes_verify_queue
(id, address, owner, email, contact, details, pgp,
lat, lon, status, verifysent, expiration)
VALUES(?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`,
		id, []byte(node.Addr), node.OwnerName, node.OwnerEmail,
		node.Contact, node.Details, []byte(node.PGP),
		node.Latitude, node.Longitude, node.Status,
		emailsent, time.Now().Add(time.Duration(grace)))
	return
}

// DeleteExpiredFromQueue removes expired nodes from the verify queue
// by checking if their expiration stamp is past the current time.
func (db DB) DeleteExpiredFromQueue() (err error) {
	_, err = db.Exec(`DELETE FROM nodes_verify_queue
WHERE expiration <= ?;`, time.Now())
	return
}

// VerifyQueuedNode removes a node (as identified by the id) from the
// queue, performs VerifyRequest checks, and inserts it into the nodes
// table. If it encounters an error, the node remains in the verify
// queue.
func (db DB) VerifyQueuedNode(id int64, r *http.Request) (addr IP, verifyerr error, err error) {
	// Get the node via the id.
	var node = new(Node)
	contact := sql.NullString{}
	details := sql.NullString{}

	err = db.QueryRow(`
SELECT address,owner,email,contact,details,pgp,lat,lon,status
FROM nodes_verify_queue WHERE id = ?;`, id).Scan(
		&node.Addr, &node.OwnerName, &node.OwnerEmail,
		&contact, &details, &node.PGP,
		&node.Latitude, &node.Longitude, &node.Status)
	if err != nil {
		return
	}
	node.Contact = contact.String
	node.Details = details.String

	// Perform VerifyRequest checks.
	verifyerr = VerifyRequest(node, r)
	if verifyerr != nil {
		return
	}

	err = db.AddNode(node)
	if err != nil {
		return
	}

	_, err = db.Exec(`DELETE FROM nodes_verify_queue
WHERE id = ?;`, id)
	if err != nil {
		l.Errf("Could not clear verified node %d: %s", id, err)
	}

	// Add it to the RSS feed. The feed will be refreshed at the next
	// heartbeat.
	AddNodeToRSS(node, time.Now())

	return node.Addr, nil, nil
}

var (
	NodeAddrNotContainedByNetmaskError = "verify: Node address not within configured netmask: %s"
)

// VerifyRegistrant performs appropriate registration-time checks to
// ensure that a Node is fit to be placed in the verification
// queue. If the given Node is acceptable, then no error will be
// returned.
func VerifyRegistrant(node *Node) error {
	// Ensure that the node's address is contained by the netmask.
	if Conf.Verify.Netmask != nil {
		if !(*net.IPNet)(Conf.Verify.Netmask).Contains(net.IP(node.Addr)) {
			return fmt.Errorf(NodeAddrNotContainedByNetmaskError,
				Conf.Verify.Netmask)
		}
	}
	return nil
}

var (
	RemoteAddressDoesNotMatchError = errors.New(
		"verify: remote address does not match Node address")
)

// VerifyRequest performs appropriate verification checks for a Node
// based on a received http.Request, as follows. Checks are only
// performed if they are enabled in the configuration. If all checks
// are successful, it returns nil.
//
// - Ensure that remote address matches the Node's address, OR it is
//   an address specified in AdminAddresses in the config.
func VerifyRequest(node *Node, r *http.Request) error {
	// Ensure that r.RemoteAddr matches node.Addr.
	if Conf.Verify.FromNode {
		if !net.IP(node.Addr).Equal(net.ParseIP(r.RemoteAddr)) &&
			!IsAdmin(r) {
			// If the node address and remote address don't match,
			// then this verify step has failed.
			return RemoteAddressDoesNotMatchError
		}
	}
	return nil
}

// SendVerificationEmail uses the fields in Conf.SMTP to send a
// templated email (verification.txt) to the given email address. If
// the email could not be sent, it returns an error.
func SendVerificationEmail(id int64, recipientEmail string) (err error) {
	// Prepare an Email type.
	e := &Email{
		To:      recipientEmail,
		From:    Conf.SMTP.EmailAddress,
		Subject: Conf.Name + " Node Registration",
	}

	e.Data = make(map[string]interface{}, 5)
	e.Data["Link"] = Conf.Web.Hostname + Conf.Web.Prefix
	e.Data["VerificationID"] = id
	e.Data["FromNode"] = Conf.Verify.FromNode
	e.Data["Flags"] = Conf.ExtraVerificationFlags

	// Generate a random number for use as a boundary marker in the
	// multipart/alternative email.
	e.Data["Boundary"] = rand.Int31()

	if err = e.Send("verification.txt"); err == nil {
		l.Debugf("Sent verification email to %d", id)
	}
	return
}

// ResendVerificationEmails attempts to resend a verification email to
// every node in the verification queue that is marked as not yet
// notified. It logs errors.
func ResendVerificationEmails() {
	rows, err := Db.Query(`SELECT id,email
FROM nodes_verify_queue
WHERE verifysent = 0;`)
	if err != nil {
		l.Errf("Error resending verification emails: %s", err)
		return
	}

	// Allocate slice so that rows can be updated later.
	verifysent := make([]int64, 0)

	for rows.Next() {
		var (
			id    int64
			email string
		)

		if err = rows.Scan(&id, &email); err != nil {
			l.Errf("Error resending verification email: %s", err)
			continue
		}

		if err = SendVerificationEmail(id, email); err != nil {
			l.Warningf("Could not send verification email to %q: %s", email, err)
		} else {
			verifysent = append(verifysent, id)
		}
	}

	setVerifysent, err := Db.Prepare(`UPDATE nodes_verify_queue
SET verifysent = 1
WHERE id = ?;`)
	if err != nil {
		l.Errf("Error preparing verifysent statement: %s", err)
		return
	}

	for _, id := range verifysent {
		if _, err = setVerifysent.Exec(id); err != nil {
			l.Warningf("Could not set verifysent for %d: %s", id, err)
		}
	}
}