diff options
author | Dmitri Shuralyov <dmitshur@golang.org> | 2018-12-13 17:08:33 -0500 |
---|---|---|
committer | Dmitri Shuralyov <dmitshur@golang.org> | 2018-12-13 17:08:33 -0500 |
commit | f40c04941aee1735de27bb2dcb71ebedba815953 (patch) | |
tree | 38427e7299d22a73b6aac92973a39d3b041240d7 | |
parent | 1ae739797ec72acbd6d90b94a2366a31566205c2 (diff) | |
parent | 25ca8f49c3fc4a68daff7a23ab613e3453be5cda (diff) | |
download | go-f40c04941aee1735de27bb2dcb71ebedba815953.tar.gz go-f40c04941aee1735de27bb2dcb71ebedba815953.zip |
[release-branch.go1.10] all: merge release-branch.go1.10-security into release-branch.go1.10
Change-Id: I7048387350b683030d9f3106979370b0d096ea38
-rw-r--r-- | VERSION | 2 | ||||
-rw-r--r-- | doc/devel/release.html | 7 | ||||
-rw-r--r-- | src/cmd/go/internal/get/get.go | 4 | ||||
-rw-r--r-- | src/cmd/go/internal/get/path.go | 192 | ||||
-rw-r--r-- | src/cmd/go/internal/get/vcs.go | 8 | ||||
-rw-r--r-- | src/crypto/x509/cert_pool.go | 28 | ||||
-rw-r--r-- | src/crypto/x509/verify.go | 86 | ||||
-rw-r--r-- | src/crypto/x509/verify_test.go | 119 |
8 files changed, 386 insertions, 60 deletions
@@ -1 +1 @@ -go1.10.5
\ No newline at end of file +go1.10.6
\ No newline at end of file diff --git a/doc/devel/release.html b/doc/devel/release.html index b8a6caf96e..cb2af29e04 100644 --- a/doc/devel/release.html +++ b/doc/devel/release.html @@ -72,6 +72,13 @@ See the <a href="https://github.com/golang/go/issues?q=milestone%3AGo1.10.5">Go 1.10.5 milestone</a> on our issue tracker for details. </p> +<p> +go1.10.6 (released 2018/12/12) includes three security fixes to "go get" and +the <code>crypto/x509</code> package. +See the <a href="https://github.com/golang/go/issues?q=milestone%3AGo1.10.6">Go +1.10.6 milestone</a> on our issue tracker for details. +</p> + <h2 id="go1.9">go1.9 (released 2017/08/24)</h2> <p> diff --git a/src/cmd/go/internal/get/get.go b/src/cmd/go/internal/get/get.go index 5bfeac387c..33b561cb37 100644 --- a/src/cmd/go/internal/get/get.go +++ b/src/cmd/go/internal/get/get.go @@ -376,6 +376,10 @@ func downloadPackage(p *load.Package) error { security = web.Insecure } + if err := CheckImportPath(p.ImportPath); err != nil { + return fmt.Errorf("%s: invalid import path: %v", p.ImportPath, err) + } + if p.Internal.Build.SrcRoot != "" { // Directory exists. Look for checkout along path to src. vcs, rootPath, err = vcsFromDir(p.Dir, p.Internal.Build.SrcRoot) diff --git a/src/cmd/go/internal/get/path.go b/src/cmd/go/internal/get/path.go new file mode 100644 index 0000000000..d443bd28a9 --- /dev/null +++ b/src/cmd/go/internal/get/path.go @@ -0,0 +1,192 @@ +// Copyright 2018 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 get + +import ( + "fmt" + "strings" + "unicode" + "unicode/utf8" +) + +// The following functions are copied verbatim from cmd/go/internal/module/module.go, +// with a change to additionally reject Windows short-names, +// and one to accept arbitrary letters (golang.org/issue/29101). +// +// TODO(bcmills): After the call site for this function is backported, +// consolidate this back down to a single copy. +// +// NOTE: DO NOT MERGE THESE UNTIL WE DECIDE ABOUT ARBITRARY LETTERS IN MODULE MODE. + +// CheckImportPath checks that an import path is valid. +func CheckImportPath(path string) error { + if err := checkPath(path, false); err != nil { + return fmt.Errorf("malformed import path %q: %v", path, err) + } + return nil +} + +// checkPath checks that a general path is valid. +// It returns an error describing why but not mentioning path. +// Because these checks apply to both module paths and import paths, +// the caller is expected to add the "malformed ___ path %q: " prefix. +// fileName indicates whether the final element of the path is a file name +// (as opposed to a directory name). +func checkPath(path string, fileName bool) error { + if !utf8.ValidString(path) { + return fmt.Errorf("invalid UTF-8") + } + if path == "" { + return fmt.Errorf("empty string") + } + if strings.Contains(path, "..") { + return fmt.Errorf("double dot") + } + if strings.Contains(path, "//") { + return fmt.Errorf("double slash") + } + if path[len(path)-1] == '/' { + return fmt.Errorf("trailing slash") + } + elemStart := 0 + for i, r := range path { + if r == '/' { + if err := checkElem(path[elemStart:i], fileName); err != nil { + return err + } + elemStart = i + 1 + } + } + if err := checkElem(path[elemStart:], fileName); err != nil { + return err + } + return nil +} + +// checkElem checks whether an individual path element is valid. +// fileName indicates whether the element is a file name (not a directory name). +func checkElem(elem string, fileName bool) error { + if elem == "" { + return fmt.Errorf("empty path element") + } + if strings.Count(elem, ".") == len(elem) { + return fmt.Errorf("invalid path element %q", elem) + } + if elem[0] == '.' && !fileName { + return fmt.Errorf("leading dot in path element") + } + if elem[len(elem)-1] == '.' { + return fmt.Errorf("trailing dot in path element") + } + + charOK := pathOK + if fileName { + charOK = fileNameOK + } + for _, r := range elem { + if !charOK(r) { + return fmt.Errorf("invalid char %q", r) + } + } + + // Windows disallows a bunch of path elements, sadly. + // See https://docs.microsoft.com/en-us/windows/desktop/fileio/naming-a-file + short := elem + if i := strings.Index(short, "."); i >= 0 { + short = short[:i] + } + for _, bad := range badWindowsNames { + if strings.EqualFold(bad, short) { + return fmt.Errorf("disallowed path element %q", elem) + } + } + + // Reject path components that look like Windows short-names. + // Those usually end in a tilde followed by one or more ASCII digits. + if tilde := strings.LastIndexByte(short, '~'); tilde >= 0 && tilde < len(short)-1 { + suffix := short[tilde+1:] + suffixIsDigits := true + for _, r := range suffix { + if r < '0' || r > '9' { + suffixIsDigits = false + break + } + } + if suffixIsDigits { + return fmt.Errorf("trailing tilde and digits in path element") + } + } + + return nil +} + +// pathOK reports whether r can appear in an import path element. +// +// NOTE: This function DIVERGES from module mode pathOK by accepting Unicode letters. +func pathOK(r rune) bool { + if r < utf8.RuneSelf { + return r == '+' || r == '-' || r == '.' || r == '_' || r == '~' || + '0' <= r && r <= '9' || + 'A' <= r && r <= 'Z' || + 'a' <= r && r <= 'z' + } + return unicode.IsLetter(r) +} + +// fileNameOK reports whether r can appear in a file name. +// For now we allow all Unicode letters but otherwise limit to pathOK plus a few more punctuation characters. +// If we expand the set of allowed characters here, we have to +// work harder at detecting potential case-folding and normalization collisions. +// See note about "safe encoding" below. +func fileNameOK(r rune) bool { + if r < utf8.RuneSelf { + // Entire set of ASCII punctuation, from which we remove characters: + // ! " # $ % & ' ( ) * + , - . / : ; < = > ? @ [ \ ] ^ _ ` { | } ~ + // We disallow some shell special characters: " ' * < > ? ` | + // (Note that some of those are disallowed by the Windows file system as well.) + // We also disallow path separators / : and \ (fileNameOK is only called on path element characters). + // We allow spaces (U+0020) in file names. + const allowed = "!#$%&()+,-.=@[]^_{}~ " + if '0' <= r && r <= '9' || 'A' <= r && r <= 'Z' || 'a' <= r && r <= 'z' { + return true + } + for i := 0; i < len(allowed); i++ { + if rune(allowed[i]) == r { + return true + } + } + return false + } + // It may be OK to add more ASCII punctuation here, but only carefully. + // For example Windows disallows < > \, and macOS disallows :, so we must not allow those. + return unicode.IsLetter(r) +} + +// badWindowsNames are the reserved file path elements on Windows. +// See https://docs.microsoft.com/en-us/windows/desktop/fileio/naming-a-file +var badWindowsNames = []string{ + "CON", + "PRN", + "AUX", + "NUL", + "COM1", + "COM2", + "COM3", + "COM4", + "COM5", + "COM6", + "COM7", + "COM8", + "COM9", + "LPT1", + "LPT2", + "LPT3", + "LPT4", + "LPT5", + "LPT6", + "LPT7", + "LPT8", + "LPT9", +} diff --git a/src/cmd/go/internal/get/vcs.go b/src/cmd/go/internal/get/vcs.go index 0b2a04e04f..58d8035416 100644 --- a/src/cmd/go/internal/get/vcs.go +++ b/src/cmd/go/internal/get/vcs.go @@ -970,10 +970,14 @@ func matchGoImport(imports []metaImport, importPath string) (metaImport, error) // expand rewrites s to replace {k} with match[k] for each key k in match. func expand(match map[string]string, s string) string { + // We want to replace each match exactly once, and the result of expansion + // must not depend on the iteration order through the map. + // A strings.Replacer has exactly the properties we're looking for. + oldNew := make([]string, 0, 2*len(match)) for k, v := range match { - s = strings.Replace(s, "{"+k+"}", v, -1) + oldNew = append(oldNew, "{"+k+"}", v) } - return s + return strings.NewReplacer(oldNew...).Replace(s) } // vcsPaths defines the meaning of import paths referring to diff --git a/src/crypto/x509/cert_pool.go b/src/crypto/x509/cert_pool.go index 71ffbdf0e0..86e8cbe869 100644 --- a/src/crypto/x509/cert_pool.go +++ b/src/crypto/x509/cert_pool.go @@ -38,32 +38,16 @@ func SystemCertPool() (*CertPool, error) { return loadSystemRoots() } -// findVerifiedParents attempts to find certificates in s which have signed the -// given certificate. If any candidates were rejected then errCert will be set -// to one of them, arbitrarily, and err will contain the reason that it was -// rejected. -func (s *CertPool) findVerifiedParents(cert *Certificate) (parents []int, errCert *Certificate, err error) { +// findPotentialParents returns the indexes of certificates in s which might +// have signed cert. The caller must not modify the returned slice. +func (s *CertPool) findPotentialParents(cert *Certificate) []int { if s == nil { - return + return nil } - var candidates []int - if len(cert.AuthorityKeyId) > 0 { - candidates = s.bySubjectKeyId[string(cert.AuthorityKeyId)] - } - if len(candidates) == 0 { - candidates = s.byName[string(cert.RawIssuer)] + return s.bySubjectKeyId[string(cert.AuthorityKeyId)] } - - for _, c := range candidates { - if err = cert.CheckSignatureFrom(s.certs[c]); err == nil { - parents = append(parents, c) - } else { - errCert = s.certs[c] - } - } - - return + return s.byName[string(cert.RawIssuer)] } func (s *CertPool) contains(cert *Certificate) bool { diff --git a/src/crypto/x509/verify.go b/src/crypto/x509/verify.go index 60e415b7ec..b70a97c952 100644 --- a/src/crypto/x509/verify.go +++ b/src/crypto/x509/verify.go @@ -765,7 +765,7 @@ func (c *Certificate) Verify(opts VerifyOptions) (chains [][]*Certificate, err e if opts.Roots.contains(c) { candidateChains = append(candidateChains, []*Certificate{c}) } else { - if candidateChains, err = c.buildChains(make(map[int][][]*Certificate), []*Certificate{c}, &opts); err != nil { + if candidateChains, err = c.buildChains(nil, []*Certificate{c}, nil, &opts); err != nil { return nil, err } } @@ -802,58 +802,74 @@ func appendToFreshChain(chain []*Certificate, cert *Certificate) []*Certificate return n } -func (c *Certificate) buildChains(cache map[int][][]*Certificate, currentChain []*Certificate, opts *VerifyOptions) (chains [][]*Certificate, err error) { - possibleRoots, failedRoot, rootErr := opts.Roots.findVerifiedParents(c) -nextRoot: - for _, rootNum := range possibleRoots { - root := opts.Roots.certs[rootNum] +// maxChainSignatureChecks is the maximum number of CheckSignatureFrom calls +// that an invocation of buildChains will (tranistively) make. Most chains are +// less than 15 certificates long, so this leaves space for multiple chains and +// for failed checks due to different intermediates having the same Subject. +const maxChainSignatureChecks = 100 +func (c *Certificate) buildChains(cache map[*Certificate][][]*Certificate, currentChain []*Certificate, sigChecks *int, opts *VerifyOptions) (chains [][]*Certificate, err error) { + var ( + hintErr error + hintCert *Certificate + ) + + considerCandidate := func(certType int, candidate *Certificate) { for _, cert := range currentChain { - if cert.Equal(root) { - continue nextRoot + if cert.Equal(candidate) { + return } } - err = root.isValid(rootCertificate, currentChain, opts) - if err != nil { - continue + if sigChecks == nil { + sigChecks = new(int) + } + *sigChecks++ + if *sigChecks > maxChainSignatureChecks { + err = errors.New("x509: signature check attempts limit reached while verifying certificate chain") + return } - chains = append(chains, appendToFreshChain(currentChain, root)) - } - possibleIntermediates, failedIntermediate, intermediateErr := opts.Intermediates.findVerifiedParents(c) -nextIntermediate: - for _, intermediateNum := range possibleIntermediates { - intermediate := opts.Intermediates.certs[intermediateNum] - for _, cert := range currentChain { - if cert.Equal(intermediate) { - continue nextIntermediate + if err := c.CheckSignatureFrom(candidate); err != nil { + if hintErr == nil { + hintErr = err + hintCert = candidate } + return } - err = intermediate.isValid(intermediateCertificate, currentChain, opts) + + err = candidate.isValid(certType, currentChain, opts) if err != nil { - continue + return } - var childChains [][]*Certificate - childChains, ok := cache[intermediateNum] - if !ok { - childChains, err = intermediate.buildChains(cache, appendToFreshChain(currentChain, intermediate), opts) - cache[intermediateNum] = childChains + + switch certType { + case rootCertificate: + chains = append(chains, appendToFreshChain(currentChain, candidate)) + case intermediateCertificate: + if cache == nil { + cache = make(map[*Certificate][][]*Certificate) + } + childChains, ok := cache[candidate] + if !ok { + childChains, err = candidate.buildChains(cache, appendToFreshChain(currentChain, candidate), sigChecks, opts) + cache[candidate] = childChains + } + chains = append(chains, childChains...) } - chains = append(chains, childChains...) + } + + for _, rootNum := range opts.Roots.findPotentialParents(c) { + considerCandidate(rootCertificate, opts.Roots.certs[rootNum]) + } + for _, intermediateNum := range opts.Intermediates.findPotentialParents(c) { + considerCandidate(intermediateCertificate, opts.Intermediates.certs[intermediateNum]) } if len(chains) > 0 { err = nil } - if len(chains) == 0 && err == nil { - hintErr := rootErr - hintCert := failedRoot - if hintErr == nil { - hintErr = intermediateErr - hintCert = failedIntermediate - } err = UnknownAuthorityError{c, hintErr, hintCert} } diff --git a/src/crypto/x509/verify_test.go b/src/crypto/x509/verify_test.go index bd3df47907..2fc760d812 100644 --- a/src/crypto/x509/verify_test.go +++ b/src/crypto/x509/verify_test.go @@ -5,10 +5,15 @@ package x509 import ( + "crypto" + "crypto/ecdsa" + "crypto/elliptic" + "crypto/rand" "crypto/x509/pkix" "encoding/pem" "errors" "fmt" + "math/big" "runtime" "strings" "testing" @@ -1707,3 +1712,117 @@ UNhY4JhezH9gQYqvDMWrWDAbBgNVHSMEFDASgBArF29S5Bnqw7de8GzGA1nfMAoG CCqGSM49BAMCA0gAMEUCIQClA3d4tdrDu9Eb5ZBpgyC+fU1xTZB0dKQHz6M5fPZA 2AIgN96lM+CPGicwhN24uQI6flOsO3H0TJ5lNzBYLtnQtlc= -----END CERTIFICATE-----` + +func generateCert(cn string, isCA bool, issuer *Certificate, issuerKey crypto.PrivateKey) (*Certificate, crypto.PrivateKey, error) { + priv, err := ecdsa.GenerateKey(elliptic.P256(), rand.Reader) + if err != nil { + return nil, nil, err + } + + serialNumberLimit := new(big.Int).Lsh(big.NewInt(1), 128) + serialNumber, _ := rand.Int(rand.Reader, serialNumberLimit) + + template := &Certificate{ + SerialNumber: serialNumber, + Subject: pkix.Name{CommonName: cn}, + NotBefore: time.Now().Add(-1 * time.Hour), + NotAfter: time.Now().Add(24 * time.Hour), + + KeyUsage: KeyUsageKeyEncipherment | KeyUsageDigitalSignature | KeyUsageCertSign, + ExtKeyUsage: []ExtKeyUsage{ExtKeyUsageServerAuth}, + BasicConstraintsValid: true, + IsCA: isCA, + } + if issuer == nil { + issuer = template + issuerKey = priv + } + + derBytes, err := CreateCertificate(rand.Reader, template, issuer, priv.Public(), issuerKey) + if err != nil { + return nil, nil, err + } + cert, err := ParseCertificate(derBytes) + if err != nil { + return nil, nil, err + } + + return cert, priv, nil +} + +func TestPathologicalChain(t *testing.T) { + if testing.Short() { + t.Skip("skipping generation of a long chain of certificates in short mode") + } + + // Build a chain where all intermediates share the same subject, to hit the + // path building worst behavior. + roots, intermediates := NewCertPool(), NewCertPool() + + parent, parentKey, err := generateCert("Root CA", true, nil, nil) + if err != nil { + t.Fatal(err) + } + roots.AddCert(parent) + + for i := 1; i < 100; i++ { + parent, parentKey, err = generateCert("Intermediate CA", true, parent, parentKey) + if err != nil { + t.Fatal(err) + } + intermediates.AddCert(parent) + } + + leaf, _, err := generateCert("Leaf", false, parent, parentKey) + if err != nil { + t.Fatal(err) + } + + start := time.Now() + _, err = leaf.Verify(VerifyOptions{ + Roots: roots, + Intermediates: intermediates, + }) + t.Logf("verification took %v", time.Since(start)) + + if err == nil || !strings.Contains(err.Error(), "signature check attempts limit") { + t.Errorf("expected verification to fail with a signature checks limit error; got %v", err) + } +} + +func TestLongChain(t *testing.T) { + if testing.Short() { + t.Skip("skipping generation of a long chain of certificates in short mode") + } + + roots, intermediates := NewCertPool(), NewCertPool() + + parent, parentKey, err := generateCert("Root CA", true, nil, nil) + if err != nil { + t.Fatal(err) + } + roots.AddCert(parent) + + for i := 1; i < 15; i++ { + name := fmt.Sprintf("Intermediate CA #%d", i) + parent, parentKey, err = generateCert(name, true, parent, parentKey) + if err != nil { + t.Fatal(err) + } + intermediates.AddCert(parent) + } + + leaf, _, err := generateCert("Leaf", false, parent, parentKey) + if err != nil { + t.Fatal(err) + } + + start := time.Now() + if _, err := leaf.Verify(VerifyOptions{ + Roots: roots, + Intermediates: intermediates, + }); err != nil { + t.Error(err) + } + t.Logf("verification took %v", time.Since(start)) +} |