tls: Improve (and fix) on-demand configuration

This commit is contained in:
Matthew Holt 2019-06-20 20:36:29 -06:00
parent 6d0350d04e
commit 269b1e9aa3
5 changed files with 104 additions and 11 deletions

3
go.mod
View file

@ -16,12 +16,13 @@ require (
github.com/imdario/mergo v0.3.7 // indirect
github.com/klauspost/compress v1.7.1-0.20190613161414-0b31f265a57b
github.com/klauspost/cpuid v1.2.1
github.com/mholt/certmagic v0.6.0
github.com/mholt/certmagic v0.6.2-0.20190621004807-be4f86a2eb60
github.com/rs/cors v1.6.0
github.com/shurcooL/sanitized_anchor_name v1.0.0 // indirect
github.com/starlight-go/starlight v0.0.0-20181207205707-b06f321544f3
go.starlark.net v0.0.0-20190604130855-6ddc71c0ba77
golang.org/x/net v0.0.0-20190603091049-60506f45cf65
golang.org/x/time v0.0.0-20190308202827-9d24e82272b4 // indirect
gopkg.in/russross/blackfriday.v2 v2.0.1
)

4
go.sum
View file

@ -36,6 +36,8 @@ github.com/mholt/certmagic v0.5.2-0.20190605043235-e49d0d405641 h1:wNqOQ0DFxcZDN
github.com/mholt/certmagic v0.5.2-0.20190605043235-e49d0d405641/go.mod h1:g4cOPxcjV0oFq3qwpjSA30LReKD8AoIfwAY9VvG35NY=
github.com/mholt/certmagic v0.6.0 h1:gZwuBuONw2v8/fZh2nd39kvjFNjnSF2uIR4GzKaaryw=
github.com/mholt/certmagic v0.6.0/go.mod h1:g4cOPxcjV0oFq3qwpjSA30LReKD8AoIfwAY9VvG35NY=
github.com/mholt/certmagic v0.6.2-0.20190621004807-be4f86a2eb60 h1:SALetD3LrWGNvna2JIwY1dG4W6rBKtoBehQtHjEKTpo=
github.com/mholt/certmagic v0.6.2-0.20190621004807-be4f86a2eb60/go.mod h1:g4cOPxcjV0oFq3qwpjSA30LReKD8AoIfwAY9VvG35NY=
github.com/miekg/dns v1.1.3 h1:1g0r1IvskvgL8rR+AcHzUA+oFmGcQlaIm4IqakufeMM=
github.com/miekg/dns v1.1.3/go.mod h1:W1PPwlIAgtquWBMBEV9nkV9Cazfe8ScdGz/Lj7v3Nrg=
github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
@ -66,5 +68,7 @@ golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a h1:1BGLXjeY4akVXGgbC9HugT3Jv
golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
golang.org/x/text v0.3.0 h1:g61tztE5qeGQ89tm6NTjjM9VPIm088od1l6aSorWRWg=
golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
golang.org/x/time v0.0.0-20190308202827-9d24e82272b4 h1:SvFZT6jyqRaOeXpc5h/JSfZenJ2O330aBsf7JfSUXmQ=
golang.org/x/time v0.0.0-20190308202827-9d24e82272b4/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
gopkg.in/square/go-jose.v2 v2.2.2 h1:orlkJ3myw8CN1nVQHBFfloD+L3egixIa4FvUP6RosSA=
gopkg.in/square/go-jose.v2 v2.2.2/go.mod h1:M9dMgbHiYLoDGQrXy7OpJDJWiKiU//h+vD76mk0e1AI=

View file

@ -3,6 +3,7 @@ package caddytls
import (
"encoding/json"
"fmt"
"net/url"
"time"
"github.com/go-acme/lego/certcrypto"
@ -30,12 +31,12 @@ func init() {
type ACMEManagerMaker struct {
CA string `json:"ca,omitempty"`
Email string `json:"email,omitempty"`
RenewAhead caddy.Duration `json:"renew_ahead,omitempty"`
RenewAhead caddy.Duration `json:"renew_ahead,omitempty"`
KeyType string `json:"key_type,omitempty"`
ACMETimeout caddy.Duration `json:"acme_timeout,omitempty"`
ACMETimeout caddy.Duration `json:"acme_timeout,omitempty"`
MustStaple bool `json:"must_staple,omitempty"`
Challenges ChallengesConfig `json:"challenges"`
OnDemand *OnDemandConfig `json:"on_demand,omitempty"`
Challenges ChallengesConfig `json:"challenges,omitempty"`
OnDemand bool `json:"on_demand,omitempty"`
Storage json.RawMessage `json:"storage,omitempty"`
storage certmagic.Storage
@ -109,9 +110,34 @@ func (m *ACMEManagerMaker) makeCertMagicConfig(ctx caddy.Context) certmagic.Conf
}
var ond *certmagic.OnDemandConfig
if m.OnDemand != nil {
if m.OnDemand {
var onDemand *OnDemandConfig
appVal, err := ctx.App("tls")
if err == nil {
onDemand = appVal.(*TLS).Automation.OnDemand
}
ond = &certmagic.OnDemandConfig{
// TODO: fill this out
DecisionFunc: func(name string) error {
if onDemand != nil {
if onDemand.Ask != "" {
err := onDemandAskRequest(onDemand.Ask, name)
if err != nil {
return err
}
}
// check the rate limiter last, since
// even checking consumes a token; so
// don't even bother checking if the
// other regulations fail anyway
if onDemand.RateLimit != nil {
if !onDemandRateLimiter.Allow() {
return fmt.Errorf("on-demand rate limit exceeded")
}
}
}
return nil
},
}
}
@ -134,6 +160,34 @@ func (m *ACMEManagerMaker) makeCertMagicConfig(ctx caddy.Context) certmagic.Conf
}
}
// onDemandAskRequest makes a request to the ask URL
// to see if a certificate can be obtained for name.
// The certificate request should be denied if this
// returns an error.
func onDemandAskRequest(ask string, name string) error {
askURL, err := url.Parse(ask)
if err != nil {
return fmt.Errorf("parsing ask URL: %v", err)
}
qs := askURL.Query()
qs.Set("domain", name)
askURL.RawQuery = qs.Encode()
resp, err := onDemandAskClient.Get(askURL.String())
if err != nil {
return fmt.Errorf("error checking %v to deterine if certificate for hostname '%s' should be allowed: %v",
ask, name, err)
}
resp.Body.Close()
if resp.StatusCode < 200 || resp.StatusCode > 299 {
return fmt.Errorf("certificate for hostname '%s' not allowed; non-2xx status code %d returned from %v",
name, resp.StatusCode, ask)
}
return nil
}
// supportedCertKeyTypes is all the key types that are supported
// for certificates that are obtained through ACME.
var supportedCertKeyTypes = map[string]certcrypto.KeyType{

View file

@ -86,6 +86,7 @@ func (cp ConnectionPolicies) TLSConfig(ctx caddy.Context) (*tls.Config, error) {
}
return pol.stdTLSConfig, nil
}
return nil, fmt.Errorf("no server TLS configuration available for ClientHello: %+v", hello)
},
}, nil
@ -148,6 +149,8 @@ func (p *ConnectionPolicy) buildStandardTLSConfig(ctx caddy.Context) error {
tlsApp.SessionTickets.unregister(cfg)
})
// TODO: Clean up active locks if app (or process) is being closed!
// add all the cipher suites in order, without duplicates
cipherSuitesAdded := make(map[uint16]struct{})
for _, csName := range p.CipherSuites {

View file

@ -5,10 +5,12 @@ import (
"encoding/json"
"fmt"
"net/http"
"time"
"github.com/caddyserver/caddy"
"github.com/go-acme/lego/challenge"
"github.com/mholt/certmagic"
"golang.org/x/time/rate"
)
func init() {
@ -71,6 +73,16 @@ func (t *TLS) Provision(ctx caddy.Context) error {
return fmt.Errorf("provisioning session tickets configuration: %v", err)
}
// on-demand rate limiting
if t.Automation.OnDemand != nil && t.Automation.OnDemand.RateLimit != nil {
limit := rate.Every(time.Duration(t.Automation.OnDemand.RateLimit.Interval))
// TODO: Burst size is not updated, see https://github.com/golang/go/issues/23575
onDemandRateLimiter.SetLimit(limit)
} else {
// if no rate limit is specified, be sure to remove any existing limit
onDemandRateLimiter.SetLimit(0)
}
return nil
}
@ -178,6 +190,7 @@ type CertificateLoader interface {
// construction and use of ACME clients.
type AutomationConfig struct {
Policies []AutomationPolicy `json:"policies,omitempty"`
OnDemand *OnDemandConfig `json:"on_demand,omitempty"`
}
// AutomationPolicy designates the policy for automating the
@ -189,6 +202,9 @@ type AutomationPolicy struct {
Management managerMaker `json:"-"`
}
// makeCertMagicConfig converts ap into a CertMagic config. Passing onDemand
// is necessary because the automation policy does not have convenient access
// to the TLS app's global on-demand policies;
func (ap AutomationPolicy) makeCertMagicConfig(ctx caddy.Context) certmagic.Config {
// default manager (ACME) is a special case because of how CertMagic is designed
// TODO: refactor certmagic so that ACME manager is not a special case by extracting
@ -226,10 +242,14 @@ type TLSALPNChallengeConfig struct {
// OnDemandConfig configures on-demand TLS, for obtaining
// needed certificates at handshake-time.
type OnDemandConfig struct {
// TODO: MaxCertificates state might not endure reloads...
// MaxCertificates int `json:"max_certificates,omitempty"`
AskURL string `json:"ask_url,omitempty"`
AskStarlark string `json:"ask_starlark,omitempty"`
RateLimit *RateLimit `json:"rate_limit,omitempty"`
Ask string `json:"ask,omitempty"`
}
// RateLimit specifies an interval with optional burst size.
type RateLimit struct {
Interval caddy.Duration `json:"interval,omitempty"`
Burst int `json:"burst,omitempty"`
}
// managerMaker makes a certificate manager.
@ -237,4 +257,15 @@ type managerMaker interface {
newManager(interactive bool) (certmagic.Manager, error)
}
// These perpetual values are used for on-demand TLS.
var (
onDemandRateLimiter = rate.NewLimiter(0, 1)
onDemandAskClient = &http.Client{
Timeout: 10 * time.Second,
CheckRedirect: func(req *http.Request, via []*http.Request) error {
return fmt.Errorf("following http redirects is not allowed")
},
}
)
const automateKey = "automate"