diff options
| -rw-r--r-- | src/cmd/go/internal/get/get.go | 4 | ||||
| -rw-r--r-- | src/cmd/go/internal/get/path.go | 172 |
2 files changed, 176 insertions, 0 deletions
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..2920fc2085 --- /dev/null +++ b/src/cmd/go/internal/get/path.go @@ -0,0 +1,172 @@ +// 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. +// +// TODO(bcmills): After the call site for this function is backported, +// consolidate this back down to a single copy. + +// 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) + } + } + return nil +} + +// pathOK reports whether r can appear in an import path element. +// Paths can be ASCII letters, ASCII digits, and limited ASCII punctuation: + - . _ and ~. +// This matches what "go get" has historically recognized in import paths. +// TODO(rsc): We would like to allow Unicode letters, but that requires additional +// care in the safe encoding (see note below). +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 false +} + +// 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", +} |