go.mod: update golang.org/x dependencies

Update golang.org/x dependencies to their latest tagged versions.
Once this CL is submitted, and post-submit testing succeeds on all
first-class ports across all supported Go versions, this repository
will be tagged with its next minor version.

Change-Id: If19e251a79af033583e6968766b7a831741cebb7
Reviewed-on: https://go-review.googlesource.com/c/crypto/+/502518
Reviewed-by: Heschi Kreinick <heschi@google.com>
Run-TryBot: Gopher Robot <gobot@golang.org>
Reviewed-by: Carlos Amedee <carlos@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Gopher Robot <gobot@golang.org>

cryptobyte/asn1.go

@@ -431,6 +431,14 @@ func (s *String) readBase128Int(out *int) bool {
 		}
 		ret <<= 7
 		b := s.read(1)[0]
+
+		// ITU-T X.690, section 8.19.2:
+		// The subidentifier shall be encoded in the fewest possible octets,
+		// that is, the leading octet of the subidentifier shall not have the value 0x80.
+		if i == 0 && b == 0x80 {
+			return false
+		}
+
 		ret |= int(b & 0x7f)
 		if b&0x80 == 0 {
 			*out = ret

cryptobyte/asn1_test.go

@@ -276,6 +276,7 @@ func TestASN1ObjectIdentifier(t *testing.T) {
 		{[]byte{6, 7, 85, 0x02, 0x85, 0xc7, 0xcc, 0xfb, 0x01}, true, []int{2, 5, 2, 1492336001}},
 		{[]byte{6, 7, 0x55, 0x02, 0x87, 0xff, 0xff, 0xff, 0x7f}, true, []int{2, 5, 2, 2147483647}}, // 2**31-1
 		{[]byte{6, 7, 0x55, 0x02, 0x88, 0x80, 0x80, 0x80, 0x00}, false, []int{}},                   // 2**31
+		{[]byte{6, 3, 85, 0x80, 0x02}, false, []int{}},                                             // leading 0x80 octet
 	}
 
 	for i, test := range testData {

go.mod

@@ -3,9 +3,9 @@ module golang.org/x/crypto
 go 1.17
 
 require (
-	golang.org/x/net v0.9.0
-	golang.org/x/sys v0.7.0
-	golang.org/x/term v0.7.0
+	golang.org/x/net v0.10.0 // tagx:ignore
+	golang.org/x/sys v0.9.0
+	golang.org/x/term v0.9.0
 )
 
-require golang.org/x/text v0.9.0 // indirect
+require golang.org/x/text v0.10.0 // indirect

go.sum

@@ -7,8 +7,8 @@ golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLL
 golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
 golang.org/x/net v0.0.0-20220722155237-a158d28d115b/go.mod h1:XRhObCWvk6IyKnWLug+ECip1KBveYUHfp+8e9klMJ9c=
 golang.org/x/net v0.6.0/go.mod h1:2Tu9+aMcznHK/AK1HMvgo6xiTLG5rD5rZLDS+rp2Bjs=
-golang.org/x/net v0.9.0 h1:aWJ/m6xSmxWBx+V0XRHTlrYrPG56jKsLdTFmsSsCzOM=
-golang.org/x/net v0.9.0/go.mod h1:d48xBJpPfHeWQsugry2m+kC02ZBRGRgulfHnEXEuWns=
+golang.org/x/net v0.10.0 h1:X2//UzNDwYmtCLn7To6G58Wr6f5ahEAQgKNzv9Y951M=
+golang.org/x/net v0.10.0/go.mod h1:0qNGK6F8kojg2nk9dLZ2mShWaEBan6FAoqfSigmmuDg=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.1.0/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
@@ -18,19 +18,22 @@ golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBc
 golang.org/x/sys v0.0.0-20220520151302-bc2c85ada10a/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.5.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.7.0 h1:3jlCCIQZPdOYu1h8BkNvLz8Kgwtae2cagcG/VamtZRU=
-golang.org/x/sys v0.7.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.8.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.9.0 h1:KS/R3tvhPqvJvwcKfnBHJwwthS11LRhmM5D59eEXa0s=
+golang.org/x/sys v0.9.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
 golang.org/x/term v0.5.0/go.mod h1:jMB1sMXY+tzblOD4FWmEbocvup2/aLOaQEp7JmGp78k=
-golang.org/x/term v0.7.0 h1:BEvjmm5fURWqcfbSKTdpkDXYBrUS1c0m8agp14W48vQ=
-golang.org/x/term v0.7.0/go.mod h1:P32HKFT3hSsZrRxla30E9HqToFYAQPCMs/zFMBUFqPY=
+golang.org/x/term v0.8.0/go.mod h1:xPskH00ivmX89bAKVGSKKtLOWNx2+17Eiy94tnKShWo=
+golang.org/x/term v0.9.0 h1:GRRCnKYhdQrD8kfRAdQ6Zcw1P0OcELxGLKJvtjVMZ28=
+golang.org/x/term v0.9.0/go.mod h1:M6DEAAIenWoTxdKrOltXcmDY3rSplQUkrvaDU5FcQyo=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
 golang.org/x/text v0.7.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8=
-golang.org/x/text v0.9.0 h1:2sjJmO8cDvYveuX97RDLsxlyUxLl+GHoLxBiRdHllBE=
 golang.org/x/text v0.9.0/go.mod h1:e1OnstbJyHTd6l/uOt8jFFHp6TRDWZR/bV3emEE/zU8=
+golang.org/x/text v0.10.0 h1:UpjohKhiEgNc0CSauXmwYftY1+LlaC75SJwh0SgCX58=
+golang.org/x/text v0.10.0/go.mod h1:TvPlkZtksWOMsz7fbANvkp4WM8x/WCo/om8BMLbz+aE=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=

ssh/common.go

@@ -85,7 +85,7 @@ var supportedHostKeyAlgos = []string{
 // This is based on RFC 4253, section 6.4, but with hmac-md5 variants removed
 // because they have reached the end of their useful life.
 var supportedMACs = []string{
-	"hmac-sha2-256-etm@openssh.com", "hmac-sha2-256", "hmac-sha1", "hmac-sha1-96",
+	"hmac-sha2-512-etm@openssh.com", "hmac-sha2-256-etm@openssh.com", "hmac-sha2-256", "hmac-sha1", "hmac-sha1-96",
 }
 
 var supportedCompressions = []string{compressionNone}

ssh/handshake_test.go

@@ -421,8 +421,8 @@ func TestHandshakeErrorHandlingWriteCoupled(t *testing.T) {
 // handshakeTransport deadlocks, the go runtime will detect it and
 // panic.
 func testHandshakeErrorHandlingN(t *testing.T, readLimit, writeLimit int, coupled bool) {
-	if runtime.GOOS == "js" && runtime.GOARCH == "wasm" {
-		t.Skip("skipping on js/wasm; see golang.org/issue/32840")
+	if (runtime.GOOS == "js" || runtime.GOOS == "wasip1") && runtime.GOARCH == "wasm" {
+		t.Skipf("skipping on %s/wasm; see golang.org/issue/32840", runtime.GOOS)
 	}
 	msg := Marshal(&serviceRequestMsg{strings.Repeat("x", int(minRekeyThreshold)/4)})
 

ssh/mac.go

@@ -10,6 +10,7 @@ import (
 	"crypto/hmac"
 	"crypto/sha1"
 	"crypto/sha256"
+	"crypto/sha512"
 	"hash"
 )
 
@@ -46,6 +47,9 @@ func (t truncatingMAC) Size() int {
 func (t truncatingMAC) BlockSize() int { return t.hmac.BlockSize() }
 
 var macModes = map[string]*macMode{
+	"hmac-sha2-512-etm@openssh.com": {64, true, func(key []byte) hash.Hash {
+		return hmac.New(sha512.New, key)
+	}},
 	"hmac-sha2-256-etm@openssh.com": {32, true, func(key []byte) hash.Hash {
 		return hmac.New(sha256.New, key)
 	}},

ssh/test/agent_unix_test.go

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd
-// +build aix darwin dragonfly freebsd linux netbsd openbsd
+//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
+// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris
 
 package test
 

ssh/test/banner_test.go

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd
-// +build aix darwin dragonfly freebsd linux netbsd openbsd
+//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
+// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris
 
 package test
 

ssh/test/cert_test.go

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd
-// +build aix darwin dragonfly freebsd linux netbsd openbsd
+//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
+// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris
 
 package test
 

ssh/test/dial_unix_test.go

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build !windows && !solaris && !js
-// +build !windows,!solaris,!js
+//go:build !windows && !js && !wasip1
+// +build !windows,!js,!wasip1
 
 package test
 

ssh/test/forward_unix_test.go

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd
-// +build aix darwin dragonfly freebsd linux netbsd openbsd
+//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
+// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris
 
 package test
 

ssh/test/session_test.go

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build !windows && !solaris && !js
-// +build !windows,!solaris,!js
+//go:build !windows && !js && !wasip1
+// +build !windows,!js,!wasip1
 
 package test
 
@@ -14,6 +14,8 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"path/filepath"
+	"regexp"
 	"runtime"
 	"strings"
 	"testing"
@@ -255,15 +257,31 @@ func TestValidTerminalMode(t *testing.T) {
 		t.Fatalf("session failed: %s", err)
 	}
 
-	stdin.Write([]byte("stty -a && exit\n"))
+	if _, err := io.WriteString(stdin, "echo SHELL $SHELL && stty -a && exit\n"); err != nil {
+		t.Fatal(err)
+	}
 
-	var buf bytes.Buffer
-	if _, err := io.Copy(&buf, stdout); err != nil {
+	buf := new(strings.Builder)
+	if _, err := io.Copy(buf, stdout); err != nil {
 		t.Fatalf("reading failed: %s", err)
 	}
 
+	if testing.Verbose() {
+		t.Logf("echo SHELL $SHELL && stty -a && exit:\n%s", buf)
+	}
+
+	shellLine := regexp.MustCompile("(?m)^SHELL (.*)$").FindStringSubmatch(buf.String())
+	if len(shellLine) != 2 {
+		t.Fatalf("missing output from echo SHELL $SHELL")
+	}
+	switch shell := filepath.Base(strings.TrimSpace(shellLine[1])); shell {
+	case "sh", "bash":
+	default:
+		t.Skipf("skipping test on non-Bourne shell %q", shell)
+	}
+
 	if sttyOutput := buf.String(); !strings.Contains(sttyOutput, "-echo ") {
-		t.Fatalf("terminal mode failure: expected -echo in stty output, got %s", sttyOutput)
+		t.Fatal("terminal mode failure: expected -echo in stty output")
 	}
 }
 

ssh/test/test_unix_test.go

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || plan9
-// +build aix darwin dragonfly freebsd linux netbsd openbsd plan9
+//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || plan9 || solaris
+// +build aix darwin dragonfly freebsd linux netbsd openbsd plan9 solaris
 
 package test
 

x509roots/fallback/fallback.go

@@ -0,0 +1,32 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build go1.20
+// +build go1.20
+
+// Package fallback embeds a set of fallback X.509 trusted roots in the
+// application by automatically invoking [x509.SetFallbackRoots]. This allows
+// the application to work correctly even if the operating system does not
+// provide a verifier or system roots pool.
+//
+// To use it, import the package like
+//
+//	import _ "golang.org/x/crypto/x509roots/fallback"
+//
+// It's recommended that only binaries, and not libraries, import this package.
+//
+// This package must be kept up to date for security and compatibility reasons.
+// Use govulncheck to be notified of when new versions of the package are
+// available.
+package fallback
+
+import "crypto/x509"
+
+func init() {
+	p := x509.NewCertPool()
+	for _, c := range bundle {
+		p.AddCert(c)
+	}
+	x509.SetFallbackRoots(p)
+}

x509roots/fallback/go.mod

@@ -0,0 +1,3 @@
+module golang.org/x/crypto/x509roots/fallback
+
+go 1.20

x509roots/gen_fallback_bundle.go

@@ -0,0 +1,136 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build gen
+// +build gen
+
+//go:generate go run gen_fallback_bundle.go
+
+package main
+
+import (
+	"bytes"
+	"crypto/sha256"
+	"encoding/pem"
+	"flag"
+	"fmt"
+	"go/format"
+	"io"
+	"log"
+	"net/http"
+	"os"
+	"sort"
+	"time"
+
+	"golang.org/x/crypto/x509roots/nss"
+)
+
+const tmpl = `// Code generated by gen.go at %s; DO NOT EDIT.
+// list hash: %x
+
+package fallback
+
+import "crypto/x509"
+import "encoding/pem"
+
+func mustParse(b []byte) []*x509.Certificate {
+	var roots []*x509.Certificate
+	for len(b) > 0 {
+		var block *pem.Block
+		block, b = pem.Decode(b)
+		if block == nil {
+			break
+		}
+		if block.Type != "CERTIFICATE" {
+			panic("unexpected PEM block type: "+block.Type)
+		}
+		cert, err := x509.ParseCertificate(block.Bytes)
+		if err != nil {
+			panic(err)
+		}
+		roots = append(roots, cert)
+	}
+	return roots
+}
+
+var bundle = mustParse([]byte(pemRoots))
+
+// Format of the PEM list is:
+//   * Subject common name
+//   * SHA256 hash
+//   * PEM block
+
+`
+
+var (
+	certDataURL  = flag.String("certdata-url", "https://hg.mozilla.org/mozilla-central/raw-file/tip/security/nss/lib/ckfw/builtins/certdata.txt", "URL to the raw certdata.txt file to parse (only one of certdata-url and certdata-path may be specified)")
+	certDataPath = flag.String("certdata-path", "", "Path to the NSS certdata.txt file to parse (only one of certdata-url and certdata-path may be specified)")
+	output       = flag.String("output", "fallback/bundle.go", "Path to file to write output to")
+)
+
+func main() {
+	flag.Parse()
+
+	if *certDataPath != "" && *certDataURL != "" {
+		log.Fatal("Only one of --certdata-url and --certdata-path may be supplied")
+	}
+
+	var certdata io.Reader
+
+	if *certDataPath != "" {
+		f, err := os.Open(*certDataPath)
+		if err != nil {
+			log.Fatalf("unable to open %q: %s", *certDataPath, err)
+		}
+		defer f.Close()
+		certdata = f
+	} else {
+		resp, err := http.Get(*certDataURL)
+		if err != nil {
+			log.Fatalf("failed to request %q: %s", *certDataURL, err)
+		}
+		defer resp.Body.Close()
+		certdata = resp.Body
+	}
+
+	certs, err := nss.Parse(certdata)
+	if err != nil {
+		log.Fatalf("failed to parse %q: %s", *certDataPath, err)
+	}
+
+	sort.Slice(certs, func(i, j int) bool {
+		return certs[i].X509.Subject.String() < certs[j].X509.Subject.String()
+	})
+
+	h := sha256.New()
+	for _, c := range certs {
+		h.Write(c.X509.Raw)
+	}
+	listHash := h.Sum(nil)
+
+	b := bytes.NewBuffer(nil)
+	b.Write([]byte(fmt.Sprintf(tmpl, time.Now().Format(time.RFC1123), listHash)))
+	b.Write([]byte("const pemRoots = `\n"))
+	for _, c := range certs {
+		if len(c.Constraints) > 0 {
+			// Until the constrained roots API lands, skip anything that has any
+			// additional constraints. Once that API is available, we can add
+			// build constraints that support both the current version and the
+			// new version.
+			continue
+		}
+		b.Write([]byte(fmt.Sprintf("# %s\n# %x\n", c.X509.Subject.String(), sha256.Sum256(c.X509.Raw))))
+		pem.Encode(b, &pem.Block{Type: "CERTIFICATE", Bytes: c.X509.Raw})
+	}
+	b.Write([]byte("`\n"))
+
+	formatted, err := format.Source(b.Bytes())
+	if err != nil {
+		log.Fatalf("failed to format source: %s", err)
+	}
+
+	if err := os.WriteFile(*output, formatted, 0644); err != nil {
+		log.Fatalf("failed to write to %q: %s", *output, err)
+	}
+}

x509roots/nss/parser.go

@@ -0,0 +1,259 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package nss provides functionality for parsing NSS certdata.txt
+// formatted certificate lists and extracting serverAuth roots. Most
+// users should not use this package themselves, and should instead
+// rely on the golang.org/x/crypto/x509roots/fallback package which
+// calls x509.SetFallbackRoots on a pre-parsed set of roots.
+package nss
+
+import (
+	"bufio"
+	"bytes"
+	"crypto/sha1"
+	"crypto/x509"
+	"errors"
+	"fmt"
+	"io"
+	"strconv"
+	"strings"
+	"time"
+)
+
+// Constraint is a constraint to be applied to a certificate or
+// certificate chain.
+type Constraint interface {
+	Kind() Kind
+}
+
+// Kind is the constraint kind, using the NSS enumeration.
+type Kind int
+
+const (
+	CKA_NSS_SERVER_DISTRUST_AFTER Kind = iota
+)
+
+// DistrustAfter is a Constraint that indicates a certificate has a
+// CKA_NSS_SERVER_DISTRUST_AFTER constraint. This constraint defines a date
+// after which any certificate issued which is rooted by the constrained
+// certificate should be distrusted.
+type DistrustAfter time.Time
+
+func (DistrustAfter) Kind() Kind {
+	return CKA_NSS_SERVER_DISTRUST_AFTER
+}
+
+// A Certificate represents a single trusted serverAuth certificate in the NSS
+// certdata.txt list and any constraints that should be applied to chains
+// rooted by it.
+type Certificate struct {
+	// Certificate is the parsed certificate
+	X509 *x509.Certificate
+	// Constraints contains a list of additional constraints that should be
+	// applied to any certificates that chain to Certificate. If there are
+	// any unknown constraints in the slice, Certificate should not be
+	// trusted.
+	Constraints []Constraint
+}
+
+func parseMulitLineOctal(s *bufio.Scanner) ([]byte, error) {
+	buf := bytes.NewBuffer(nil)
+	for s.Scan() {
+		if s.Text() == "END" {
+			break
+		}
+		b, err := strconv.Unquote(fmt.Sprintf("\"%s\"", s.Text()))
+		if err != nil {
+			return nil, err
+		}
+		buf.Write([]byte(b))
+	}
+	return buf.Bytes(), nil
+}
+
+type certObj struct {
+	c             *x509.Certificate
+	DistrustAfter *time.Time
+}
+
+func parseCertClass(s *bufio.Scanner) ([sha1.Size]byte, *certObj, error) {
+	var h [sha1.Size]byte
+	co := &certObj{}
+	for s.Scan() {
+		l := s.Text()
+		if l == "" {
+			// assume an empty newline indicates the end of a block
+			break
+		}
+		if strings.HasPrefix(l, "CKA_VALUE") {
+			b, err := parseMulitLineOctal(s)
+			if err != nil {
+				return h, nil, err
+			}
+			co.c, err = x509.ParseCertificate(b)
+			if err != nil {
+				return h, nil, err
+			}
+			h = sha1.Sum(b)
+		} else if strings.HasPrefix(l, "CKA_NSS_MOZILLA_CA_POLICY CK_BBOOL CK_FALSE") {
+			// we don't want it
+			return h, nil, nil
+		} else if l == "CKA_NSS_SERVER_DISTRUST_AFTER MULTILINE_OCTAL" {
+			dateStr, err := parseMulitLineOctal(s)
+			if err != nil {
+				return h, nil, err
+			}
+			t, err := time.Parse("060102150405Z0700", string(dateStr))
+			if err != nil {
+				return h, nil, err
+			}
+			co.DistrustAfter = &t
+		}
+	}
+	if co.c == nil {
+		return h, nil, errors.New("malformed CKO_CERTIFICATE object")
+	}
+	return h, co, nil
+}
+
+type trustObj struct {
+	trusted bool
+}
+
+func parseTrustClass(s *bufio.Scanner) ([sha1.Size]byte, *trustObj, error) {
+	var h [sha1.Size]byte
+	to := &trustObj{trusted: false} // default to untrusted
+
+	for s.Scan() {
+		l := s.Text()
+		if l == "" {
+			// assume an empty newline indicates the end of a block
+			break
+		}
+		if l == "CKA_CERT_SHA1_HASH MULTILINE_OCTAL" {
+			hash, err := parseMulitLineOctal(s)
+			if err != nil {
+				return h, nil, err
+			}
+			copy(h[:], hash)
+		} else if l == "CKA_TRUST_SERVER_AUTH CK_TRUST CKT_NSS_TRUSTED_DELEGATOR" {
+			// we only care about server auth
+			to.trusted = true
+		}
+	}
+
+	return h, to, nil
+}
+
+// Parse parses a NSS certdata.txt formatted file, returning only
+// trusted serverAuth roots, as well as any additional constraints. This parser
+// is very opinionated, only returning roots that are currently trusted for
+// serverAuth. As such roots returned by this package should only be used for
+// making trust decisions about serverAuth certificates, as the trust status for
+// other uses is not considered. Using the roots returned by this package for
+// trust decisions should be done carefully.
+//
+// Some roots returned by the parser may include additional constraints
+// (currently only DistrustAfter) which need to be considered when verifying
+// certificates which chain to them.
+//
+// Parse is not intended to be a general purpose parser for certdata.txt.
+func Parse(r io.Reader) ([]*Certificate, error) {
+	// certdata.txt is a rather strange format. It is essentially a list of
+	// textual PKCS#11 objects, delimited by empty lines. There are two main
+	// types of objects, certificates (CKO_CERTIFICATE) and trust definitions
+	// (CKO_NSS_TRUST). These objects appear to alternate, but this ordering is
+	// not defined anywhere, and should probably not be relied on. A single root
+	// certificate requires both the certificate object and the trust definition
+	// object in order to be properly understood.
+	//
+	// The list contains not just serverAuth certificates, so we need to be
+	// careful to only extract certificates which have the serverAuth trust bit
+	// set. Similarly there are a number of trust related bool fields that
+	// appear to _always_ be CKA_TRUE, but it seems unsafe to assume this is the
+	// case, so we should always double check.
+	//
+	// Since we only really care about a couple of fields, this parser throws
+	// away a lot of information, essentially just consuming CKA_CLASS objects
+	// and looking for the individual fields we care about. We could write a
+	// siginificantly more complex parser, which handles the entire format, but
+	// it feels like that would be over engineered for the little information
+	// that we really care about.
+
+	scanner := bufio.NewScanner(r)
+
+	type nssEntry struct {
+		cert  *certObj
+		trust *trustObj
+	}
+	entries := map[[sha1.Size]byte]*nssEntry{}
+
+	for scanner.Scan() {
+		// scan until we hit CKA_CLASS
+		if !strings.HasPrefix(scanner.Text(), "CKA_CLASS") {
+			continue
+		}
+
+		f := strings.Fields(scanner.Text())
+		if len(f) != 3 {
+			return nil, errors.New("malformed CKA_CLASS")
+		}
+		switch f[2] {
+		case "CKO_CERTIFICATE":
+			h, co, err := parseCertClass(scanner)
+			if err != nil {
+				return nil, err
+			}
+			if co != nil {
+				e, ok := entries[h]
+				if !ok {
+					e = &nssEntry{}
+					entries[h] = e
+				}
+				e.cert = co
+			}
+
+		case "CKO_NSS_TRUST":
+			h, to, err := parseTrustClass(scanner)
+			if err != nil {
+				return nil, err
+			}
+			if to != nil {
+				e, ok := entries[h]
+				if !ok {
+					e = &nssEntry{}
+					entries[h] = e
+				}
+				e.trust = to
+			}
+		}
+	}
+	if err := scanner.Err(); err != nil {
+		return nil, err
+	}
+
+	var certs []*Certificate
+	for h, e := range entries {
+		if e.cert == nil && e.trust != nil {
+			// We may skip some certificates which are distrusted due to mozilla
+			// policy (CKA_NSS_MOZILLA_CA_POLICY CK_BBOOL CK_FALSE), which means
+			// we might get entries that appear to have a trust object, but no
+			// certificate. We can just continue on here.
+			continue
+		} else if e.cert != nil && e.trust == nil {
+			return nil, fmt.Errorf("missing trust object for certificate with SHA1 hash: %x", h)
+		}
+		if !e.trust.trusted {
+			continue
+		}
+		nssCert := &Certificate{X509: e.cert.c}
+		if e.cert.DistrustAfter != nil {
+			nssCert.Constraints = append(nssCert.Constraints, DistrustAfter(*e.cert.DistrustAfter))
+		}
+		certs = append(certs, nssCert)
+	}
+
+	return certs, nil
+}