caddy/caddyconfig/httpcaddyfile/tlsapp.go
Matthew Holt b3d35a4995
httpcaddyfile: Don't put localhost in public APs (fix #4220)
If an email is specified in global options, a site called 'localhost' shouldn't be bunched together with public DNS names in the automation policies, which get the default, public-CA issuers. Fix old test that did this.

I also noticed that these two:

    localhost {
    }
    example.com {
    }

and

    localhost, example.com {
    }

produce slightly different TLS automation policies. The former is what the new test case covers, and we have logic that removes the empty automation policy for localhost so that auto-HTTPS can implicitly create one. (We prefer that whenever possible.) But the latter case produces two automation policies, with the second one being for localhost, with an explicit internal issuer. It's not wrong, just more explicit than it needs to be.

I'd really like to completely rewrite the code from scratch that generates automation policies, hopefully there is a simpler, more correct algorithm.
2021-06-25 11:28:32 -06:00

633 lines
23 KiB
Go

// Copyright 2015 Matthew Holt and The Caddy Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package httpcaddyfile
import (
"bytes"
"encoding/json"
"fmt"
"reflect"
"sort"
"strconv"
"strings"
"github.com/caddyserver/caddy/v2"
"github.com/caddyserver/caddy/v2/caddyconfig"
"github.com/caddyserver/caddy/v2/modules/caddyhttp"
"github.com/caddyserver/caddy/v2/modules/caddytls"
"github.com/caddyserver/certmagic"
"github.com/mholt/acmez/acme"
)
func (st ServerType) buildTLSApp(
pairings []sbAddrAssociation,
options map[string]interface{},
warnings []caddyconfig.Warning,
) (*caddytls.TLS, []caddyconfig.Warning, error) {
tlsApp := &caddytls.TLS{CertificatesRaw: make(caddy.ModuleMap)}
var certLoaders []caddytls.CertificateLoader
httpPort := strconv.Itoa(caddyhttp.DefaultHTTPPort)
if hp, ok := options["http_port"].(int); ok {
httpPort = strconv.Itoa(hp)
}
httpsPort := strconv.Itoa(caddyhttp.DefaultHTTPSPort)
if hsp, ok := options["https_port"].(int); ok {
httpsPort = strconv.Itoa(hsp)
}
// count how many server blocks have a TLS-enabled key with
// no host, and find all hosts that share a server block with
// a hostless key, so that they don't get forgotten/omitted
// by auto-HTTPS (since they won't appear in route matchers)
var serverBlocksWithTLSHostlessKey int
httpsHostsSharedWithHostlessKey := make(map[string]struct{})
for _, pair := range pairings {
for _, sb := range pair.serverBlocks {
for _, addr := range sb.keys {
if addr.Host == "" {
// this address has no hostname, but if it's explicitly set
// to HTTPS, then we need to count it as being TLS-enabled
if addr.Scheme == "https" || addr.Port == httpsPort {
serverBlocksWithTLSHostlessKey++
}
// this server block has a hostless key, now
// go through and add all the hosts to the set
for _, otherAddr := range sb.keys {
if otherAddr.Original == addr.Original {
continue
}
if otherAddr.Host != "" && otherAddr.Scheme != "http" && otherAddr.Port != httpPort {
httpsHostsSharedWithHostlessKey[otherAddr.Host] = struct{}{}
}
}
break
}
}
}
}
// a catch-all automation policy is used as a "default" for all subjects that
// don't have custom configuration explicitly associated with them; this
// is only to add if the global settings or defaults are non-empty
catchAllAP, err := newBaseAutomationPolicy(options, warnings, false)
if err != nil {
return nil, warnings, err
}
if catchAllAP != nil {
if tlsApp.Automation == nil {
tlsApp.Automation = new(caddytls.AutomationConfig)
}
tlsApp.Automation.Policies = append(tlsApp.Automation.Policies, catchAllAP)
}
for _, p := range pairings {
// avoid setting up TLS automation policies for a server that is HTTP-only
if !listenersUseAnyPortOtherThan(p.addresses, httpPort) {
continue
}
for _, sblock := range p.serverBlocks {
// get values that populate an automation policy for this block
ap, err := newBaseAutomationPolicy(options, warnings, true)
if err != nil {
return nil, warnings, err
}
sblockHosts := sblock.hostsFromKeys(false)
if len(sblockHosts) == 0 && catchAllAP != nil {
ap = catchAllAP
}
// on-demand tls
if _, ok := sblock.pile["tls.on_demand"]; ok {
ap.OnDemand = true
}
if keyTypeVals, ok := sblock.pile["tls.key_type"]; ok {
ap.KeyType = keyTypeVals[0].Value.(string)
}
// certificate issuers
if issuerVals, ok := sblock.pile["tls.cert_issuer"]; ok {
var issuers []certmagic.Issuer
for _, issuerVal := range issuerVals {
issuers = append(issuers, issuerVal.Value.(certmagic.Issuer))
}
if ap == catchAllAP && !reflect.DeepEqual(ap.Issuers, issuers) {
return nil, warnings, fmt.Errorf("automation policy from site block is also default/catch-all policy because of key without hostname, and the two are in conflict: %#v != %#v", ap.Issuers, issuers)
}
ap.Issuers = issuers
}
// custom bind host
for _, cfgVal := range sblock.pile["bind"] {
for _, iss := range ap.Issuers {
// if an issuer was already configured and it is NOT an ACME issuer,
// skip, since we intend to adjust only ACME issuers; ensure we
// include any issuer that embeds/wraps an underlying ACME issuer
var acmeIssuer *caddytls.ACMEIssuer
if acmeWrapper, ok := iss.(acmeCapable); ok {
acmeIssuer = acmeWrapper.GetACMEIssuer()
}
if acmeIssuer == nil {
continue
}
// proceed to configure the ACME issuer's bind host, without
// overwriting any existing settings
if acmeIssuer.Challenges == nil {
acmeIssuer.Challenges = new(caddytls.ChallengesConfig)
}
if acmeIssuer.Challenges.BindHost == "" {
// only binding to one host is supported
var bindHost string
if bindHosts, ok := cfgVal.Value.([]string); ok && len(bindHosts) > 0 {
bindHost = bindHosts[0]
}
acmeIssuer.Challenges.BindHost = bindHost
}
}
}
// first make sure this block is allowed to create an automation policy;
// doing so is forbidden if it has a key with no host (i.e. ":443")
// and if there is a different server block that also has a key with no
// host -- since a key with no host matches any host, we need its
// associated automation policy to have an empty Subjects list, i.e. no
// host filter, which is indistinguishable between the two server blocks
// because automation is not done in the context of a particular server...
// this is an example of a poor mapping from Caddyfile to JSON but that's
// the least-leaky abstraction I could figure out
if len(sblockHosts) == 0 {
if serverBlocksWithTLSHostlessKey > 1 {
// this server block and at least one other has a key with no host,
// making the two indistinguishable; it is misleading to define such
// a policy within one server block since it actually will apply to
// others as well
return nil, warnings, fmt.Errorf("cannot make a TLS automation policy from a server block that has a host-less address when there are other TLS-enabled server block addresses lacking a host")
}
if catchAllAP == nil {
// this server block has a key with no hosts, but there is not yet
// a catch-all automation policy (probably because no global options
// were set), so this one becomes it
catchAllAP = ap
}
}
// associate our new automation policy with this server block's hosts
ap.Subjects = sblock.hostsFromKeysNotHTTP(httpPort)
sort.Strings(ap.Subjects) // solely for deterministic test results
// if a combination of public and internal names were given
// for this same server block and no issuer was specified, we
// need to separate them out in the automation policies so
// that the internal names can use the internal issuer and
// the other names can use the default/public/ACME issuer
var ap2 *caddytls.AutomationPolicy
if len(ap.Issuers) == 0 {
var internal, external []string
for _, s := range ap.Subjects {
if !certmagic.SubjectQualifiesForCert(s) {
return nil, warnings, fmt.Errorf("subject does not qualify for certificate: '%s'", s)
}
// we don't use certmagic.SubjectQualifiesForPublicCert() because of one nuance:
// names like *.*.tld that may not qualify for a public certificate are actually
// fine when used with OnDemand, since OnDemand (currently) does not obtain
// wildcards (if it ever does, there will be a separate config option to enable
// it that we would need to check here) since the hostname is known at handshake;
// and it is unexpected to switch to internal issuer when the user wants to get
// regular certificates on-demand for a class of certs like *.*.tld.
if subjectQualifiesForPublicCert(ap, s) {
external = append(external, s)
} else {
internal = append(internal, s)
}
}
if len(external) > 0 && len(internal) > 0 {
ap.Subjects = external
apCopy := *ap
ap2 = &apCopy
ap2.Subjects = internal
ap2.IssuersRaw = []json.RawMessage{caddyconfig.JSONModuleObject(caddytls.InternalIssuer{}, "module", "internal", &warnings)}
}
}
if tlsApp.Automation == nil {
tlsApp.Automation = new(caddytls.AutomationConfig)
}
tlsApp.Automation.Policies = append(tlsApp.Automation.Policies, ap)
if ap2 != nil {
tlsApp.Automation.Policies = append(tlsApp.Automation.Policies, ap2)
}
// certificate loaders
if clVals, ok := sblock.pile["tls.cert_loader"]; ok {
for _, clVal := range clVals {
certLoaders = append(certLoaders, clVal.Value.(caddytls.CertificateLoader))
}
}
}
}
// group certificate loaders by module name, then add to config
if len(certLoaders) > 0 {
loadersByName := make(map[string]caddytls.CertificateLoader)
for _, cl := range certLoaders {
name := caddy.GetModuleName(cl)
// ugh... technically, we may have multiple FileLoader and FolderLoader
// modules (because the tls directive returns one per occurrence), but
// the config structure expects only one instance of each kind of loader
// module, so we have to combine them... instead of enumerating each
// possible cert loader module in a type switch, we can use reflection,
// which works on any cert loaders that are slice types
if reflect.TypeOf(cl).Kind() == reflect.Slice {
combined := reflect.ValueOf(loadersByName[name])
if !combined.IsValid() {
combined = reflect.New(reflect.TypeOf(cl)).Elem()
}
clVal := reflect.ValueOf(cl)
for i := 0; i < clVal.Len(); i++ {
combined = reflect.Append(combined, clVal.Index(i))
}
loadersByName[name] = combined.Interface().(caddytls.CertificateLoader)
}
}
for certLoaderName, loaders := range loadersByName {
tlsApp.CertificatesRaw[certLoaderName] = caddyconfig.JSON(loaders, &warnings)
}
}
// set any of the on-demand options, for if/when on-demand TLS is enabled
if onDemand, ok := options["on_demand_tls"].(*caddytls.OnDemandConfig); ok {
if tlsApp.Automation == nil {
tlsApp.Automation = new(caddytls.AutomationConfig)
}
tlsApp.Automation.OnDemand = onDemand
}
// set the storage clean interval if configured
if storageCleanInterval, ok := options["storage_clean_interval"].(caddy.Duration); ok {
if tlsApp.Automation == nil {
tlsApp.Automation = new(caddytls.AutomationConfig)
}
tlsApp.Automation.StorageCleanInterval = storageCleanInterval
}
// if any hostnames appear on the same server block as a key with
// no host, they will not be used with route matchers because the
// hostless key matches all hosts, therefore, it wouldn't be
// considered for auto-HTTPS, so we need to make sure those hosts
// are manually considered for managed certificates; we also need
// to make sure that any of these names which are internal-only
// get internal certificates by default rather than ACME
var al caddytls.AutomateLoader
internalAP := &caddytls.AutomationPolicy{
IssuersRaw: []json.RawMessage{json.RawMessage(`{"module":"internal"}`)},
}
for h := range httpsHostsSharedWithHostlessKey {
al = append(al, h)
if !certmagic.SubjectQualifiesForPublicCert(h) {
internalAP.Subjects = append(internalAP.Subjects, h)
}
}
if len(al) > 0 {
tlsApp.CertificatesRaw["automate"] = caddyconfig.JSON(al, &warnings)
}
if len(internalAP.Subjects) > 0 {
if tlsApp.Automation == nil {
tlsApp.Automation = new(caddytls.AutomationConfig)
}
tlsApp.Automation.Policies = append(tlsApp.Automation.Policies, internalAP)
}
// if there are any global options set for issuers (ACME ones in particular), make sure they
// take effect in every automation policy that does not have any issuers
if tlsApp.Automation != nil {
globalEmail := options["email"]
globalACMECA := options["acme_ca"]
globalACMECARoot := options["acme_ca_root"]
globalACMEDNS := options["acme_dns"]
globalACMEEAB := options["acme_eab"]
globalPreferredChains := options["preferred_chains"]
hasGlobalACMEDefaults := globalEmail != nil || globalACMECA != nil || globalACMECARoot != nil || globalACMEDNS != nil || globalACMEEAB != nil || globalPreferredChains != nil
if hasGlobalACMEDefaults {
// for _, ap := range tlsApp.Automation.Policies {
for i := 0; i < len(tlsApp.Automation.Policies); i++ {
ap := tlsApp.Automation.Policies[i]
if len(ap.Issuers) == 0 && automationPolicyHasAllPublicNames(ap) {
// for public names, create default issuers which will later be filled in with configured global defaults
// (internal names will implicitly use the internal issuer at auto-https time)
ap.Issuers = caddytls.DefaultIssuers()
// if a specific endpoint is configured, can't use multiple default issuers
if globalACMECA != nil {
if strings.Contains(globalACMECA.(string), "zerossl") {
ap.Issuers = []certmagic.Issuer{&caddytls.ZeroSSLIssuer{ACMEIssuer: new(caddytls.ACMEIssuer)}}
} else {
ap.Issuers = []certmagic.Issuer{new(caddytls.ACMEIssuer)}
}
}
}
}
}
}
// finalize and verify policies; do cleanup
if tlsApp.Automation != nil {
for i, ap := range tlsApp.Automation.Policies {
// ensure all issuers have global defaults filled in
for j, issuer := range ap.Issuers {
err := fillInGlobalACMEDefaults(issuer, options)
if err != nil {
return nil, warnings, fmt.Errorf("filling in global issuer defaults for AP %d, issuer %d: %v", i, j, err)
}
}
// encode all issuer values we created, so they will be rendered in the output
if len(ap.Issuers) > 0 && ap.IssuersRaw == nil {
for _, iss := range ap.Issuers {
issuerName := iss.(caddy.Module).CaddyModule().ID.Name()
ap.IssuersRaw = append(ap.IssuersRaw, caddyconfig.JSONModuleObject(iss, "module", issuerName, &warnings))
}
}
}
// consolidate automation policies that are the exact same
tlsApp.Automation.Policies = consolidateAutomationPolicies(tlsApp.Automation.Policies)
// ensure automation policies don't overlap subjects (this should be
// an error at provision-time as well, but catch it in the adapt phase
// for convenience)
automationHostSet := make(map[string]struct{})
for _, ap := range tlsApp.Automation.Policies {
for _, s := range ap.Subjects {
if _, ok := automationHostSet[s]; ok {
return nil, warnings, fmt.Errorf("hostname appears in more than one automation policy, making certificate management ambiguous: %s", s)
}
automationHostSet[s] = struct{}{}
}
}
// if nothing remains, remove any excess values to clean up the resulting config
if len(tlsApp.Automation.Policies) == 0 {
tlsApp.Automation.Policies = nil
}
if reflect.DeepEqual(tlsApp.Automation, new(caddytls.AutomationConfig)) {
tlsApp.Automation = nil
}
}
return tlsApp, warnings, nil
}
type acmeCapable interface{ GetACMEIssuer() *caddytls.ACMEIssuer }
func fillInGlobalACMEDefaults(issuer certmagic.Issuer, options map[string]interface{}) error {
acmeWrapper, ok := issuer.(acmeCapable)
if !ok {
return nil
}
acmeIssuer := acmeWrapper.GetACMEIssuer()
if acmeIssuer == nil {
return nil
}
globalEmail := options["email"]
globalACMECA := options["acme_ca"]
globalACMECARoot := options["acme_ca_root"]
globalACMEDNS := options["acme_dns"]
globalACMEEAB := options["acme_eab"]
globalPreferredChains := options["preferred_chains"]
if globalEmail != nil && acmeIssuer.Email == "" {
acmeIssuer.Email = globalEmail.(string)
}
if globalACMECA != nil && acmeIssuer.CA == "" {
acmeIssuer.CA = globalACMECA.(string)
}
if globalACMECARoot != nil && !sliceContains(acmeIssuer.TrustedRootsPEMFiles, globalACMECARoot.(string)) {
acmeIssuer.TrustedRootsPEMFiles = append(acmeIssuer.TrustedRootsPEMFiles, globalACMECARoot.(string))
}
if globalACMEDNS != nil && (acmeIssuer.Challenges == nil || acmeIssuer.Challenges.DNS == nil) {
acmeIssuer.Challenges = &caddytls.ChallengesConfig{
DNS: &caddytls.DNSChallengeConfig{
ProviderRaw: caddyconfig.JSONModuleObject(globalACMEDNS, "name", globalACMEDNS.(caddy.Module).CaddyModule().ID.Name(), nil),
},
}
}
if globalACMEEAB != nil && acmeIssuer.ExternalAccount == nil {
acmeIssuer.ExternalAccount = globalACMEEAB.(*acme.EAB)
}
if globalPreferredChains != nil && acmeIssuer.PreferredChains == nil {
acmeIssuer.PreferredChains = globalPreferredChains.(*caddytls.ChainPreference)
}
return nil
}
// newBaseAutomationPolicy returns a new TLS automation policy that gets
// its values from the global options map. It should be used as the base
// for any other automation policies. A nil policy (and no error) will be
// returned if there are no default/global options. However, if always is
// true, a non-nil value will always be returned (unless there is an error).
func newBaseAutomationPolicy(options map[string]interface{}, warnings []caddyconfig.Warning, always bool) (*caddytls.AutomationPolicy, error) {
issuers, hasIssuers := options["cert_issuer"]
_, hasLocalCerts := options["local_certs"]
keyType, hasKeyType := options["key_type"]
ocspStapling, hasOCSPStapling := options["ocsp_stapling"]
hasGlobalAutomationOpts := hasIssuers || hasLocalCerts || hasKeyType || hasOCSPStapling
// if there are no global options related to automation policies
// set, then we can just return right away
if !hasGlobalAutomationOpts {
if always {
return new(caddytls.AutomationPolicy), nil
}
return nil, nil
}
ap := new(caddytls.AutomationPolicy)
if hasKeyType {
ap.KeyType = keyType.(string)
}
if hasIssuers && hasLocalCerts {
return nil, fmt.Errorf("global options are ambiguous: local_certs is confusing when combined with cert_issuer, because local_certs is also a specific kind of issuer")
}
if hasIssuers {
ap.Issuers = issuers.([]certmagic.Issuer)
} else if hasLocalCerts {
ap.Issuers = []certmagic.Issuer{new(caddytls.InternalIssuer)}
}
if hasOCSPStapling {
ocspConfig := ocspStapling.(certmagic.OCSPConfig)
ap.DisableOCSPStapling = ocspConfig.DisableStapling
ap.OCSPOverrides = ocspConfig.ResponderOverrides
}
return ap, nil
}
// consolidateAutomationPolicies combines automation policies that are the same,
// for a cleaner overall output.
func consolidateAutomationPolicies(aps []*caddytls.AutomationPolicy) []*caddytls.AutomationPolicy {
// sort from most specific to least specific; we depend on this ordering
sort.SliceStable(aps, func(i, j int) bool {
if automationPolicyIsSubset(aps[i], aps[j]) {
return true
}
if automationPolicyIsSubset(aps[j], aps[i]) {
return false
}
return len(aps[i].Subjects) > len(aps[j].Subjects)
})
emptyAPCount := 0
origLenAPs := len(aps)
// compute the number of empty policies (disregarding subjects) - see #4128
emptyAP := new(caddytls.AutomationPolicy)
for i := 0; i < len(aps); i++ {
emptyAP.Subjects = aps[i].Subjects
if reflect.DeepEqual(aps[i], emptyAP) {
emptyAPCount++
if !automationPolicyHasAllPublicNames(aps[i]) {
// if this automation policy has internal names, we might as well remove it
// so auto-https can implicitly use the internal issuer
aps = append(aps[:i], aps[i+1:]...)
i--
}
}
}
// If all policies are empty, we can return nil, as there is no need to set any policy
if emptyAPCount == origLenAPs {
return nil
}
// remove or combine duplicate policies
outer:
for i := 0; i < len(aps); i++ {
// compare only with next policies; we sorted by specificity so we must not delete earlier policies
for j := i + 1; j < len(aps); j++ {
// if they're exactly equal in every way, just keep one of them
if reflect.DeepEqual(aps[i], aps[j]) {
aps = append(aps[:j], aps[j+1:]...)
// must re-evaluate current i against next j; can't skip it!
// even if i decrements to -1, will be incremented to 0 immediately
i--
continue outer
}
// if the policy is the same, we can keep just one, but we have
// to be careful which one we keep; if only one has any hostnames
// defined, then we need to keep the one without any hostnames,
// otherwise the one without any subjects (a catch-all) would be
// eaten up by the one with subjects; and if both have subjects, we
// need to combine their lists
if reflect.DeepEqual(aps[i].IssuersRaw, aps[j].IssuersRaw) &&
bytes.Equal(aps[i].StorageRaw, aps[j].StorageRaw) &&
aps[i].MustStaple == aps[j].MustStaple &&
aps[i].KeyType == aps[j].KeyType &&
aps[i].OnDemand == aps[j].OnDemand &&
aps[i].RenewalWindowRatio == aps[j].RenewalWindowRatio {
if len(aps[i].Subjects) > 0 && len(aps[j].Subjects) == 0 {
// later policy (at j) has no subjects ("catch-all"), so we can
// remove the identical-but-more-specific policy that comes first
// AS LONG AS it is not shadowed by another policy before it; e.g.
// if policy i is for example.com, policy i+1 is '*.com', and policy
// j is catch-all, we cannot remove policy i because that would
// cause example.com to be served by the less specific policy for
// '*.com', which might be different (yes we've seen this happen)
if automationPolicyShadows(i, aps) >= j {
aps = append(aps[:i], aps[i+1:]...)
i--
continue outer
}
} else {
// avoid repeated subjects
for _, subj := range aps[j].Subjects {
if !sliceContains(aps[i].Subjects, subj) {
aps[i].Subjects = append(aps[i].Subjects, subj)
}
}
aps = append(aps[:j], aps[j+1:]...)
j--
}
}
}
}
return aps
}
// automationPolicyIsSubset returns true if a's subjects are a subset
// of b's subjects.
func automationPolicyIsSubset(a, b *caddytls.AutomationPolicy) bool {
if len(b.Subjects) == 0 {
return true
}
if len(a.Subjects) == 0 {
return false
}
for _, aSubj := range a.Subjects {
var inSuperset bool
for _, bSubj := range b.Subjects {
if certmagic.MatchWildcard(aSubj, bSubj) {
inSuperset = true
break
}
}
if !inSuperset {
return false
}
}
return true
}
// automationPolicyShadows returns the index of a policy that aps[i] shadows;
// in other words, for all policies after position i, if that policy covers
// the same subjects but is less specific, that policy's position is returned,
// or -1 if no shadowing is found. For example, if policy i is for
// "foo.example.com" and policy i+2 is for "*.example.com", then i+2 will be
// returned, since that policy is shadowed by i, which is in front.
func automationPolicyShadows(i int, aps []*caddytls.AutomationPolicy) int {
for j := i + 1; j < len(aps); j++ {
if automationPolicyIsSubset(aps[i], aps[j]) {
return j
}
}
return -1
}
// subjectQualifiesForPublicCert is like certmagic.SubjectQualifiesForPublicCert() except
// that this allows domains with multiple wildcard levels like '*.*.example.com' to qualify
// if the automation policy has OnDemand enabled (i.e. this function is more lenient).
func subjectQualifiesForPublicCert(ap *caddytls.AutomationPolicy, subj string) bool {
return !certmagic.SubjectIsIP(subj) &&
!certmagic.SubjectIsInternal(subj) &&
(strings.Count(subj, "*.") < 2 || ap.OnDemand)
}
func automationPolicyHasAllPublicNames(ap *caddytls.AutomationPolicy) bool {
for _, subj := range ap.Subjects {
if !subjectQualifiesForPublicCert(ap, subj) {
return false
}
}
return true
}