blob: e20dcceb02b056240d1adaecff04e36f3a13038c [file] [log] [blame]
// 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 report
import (
"errors"
"fmt"
"regexp"
"sort"
"strings"
"golang.org/x/vulndb/internal/proxy"
"golang.org/x/vulndb/internal/version"
)
func (r *Report) Fix(pc *proxy.Client) {
for _, ref := range r.References {
ref.URL = fixURL(ref.URL)
}
for _, m := range r.Modules {
m.FixVersions(pc)
}
fixLines := func(sp *string) {
*sp = fixLineLength(*sp, maxLineLength)
}
fixLines(&r.Summary)
fixLines(&r.Description)
if r.CVEMetadata != nil {
fixLines(&r.CVEMetadata.Description)
}
}
// FixVersions replaces each version with its canonical form (if possible),
// sorts version ranges, and collects version ranges into a compact form.
func (m *Module) FixVersions(pc *proxy.Client) {
fixVersion := func(v string) string {
if v == "" {
return ""
}
if version.IsCommitHash(v) {
if c, err := pc.CanonicalModuleVersion(m.Module, v); err == nil { // no error
v = c
}
}
v = version.TrimPrefix(v)
if version.IsValid(v) {
v = version.Canonical(v)
}
return v
}
for i, vr := range m.Versions {
m.Versions[i].Introduced = fixVersion(vr.Introduced)
m.Versions[i].Fixed = fixVersion(vr.Fixed)
}
m.VulnerableAt = fixVersion(m.VulnerableAt)
sort.SliceStable(m.Versions, func(i, j int) bool {
intro, fixed := m.Versions[i].Introduced, m.Versions[i].Fixed
intro2, fixed2 := m.Versions[j].Introduced, m.Versions[j].Fixed
switch {
case intro != "" && intro2 != "":
return version.Before(intro, intro2)
case intro != "" && fixed2 != "":
return version.Before(intro, fixed2)
case fixed != "" && intro2 != "":
return version.Before(fixed, intro2)
case fixed != "" && fixed2 != "":
return version.Before(fixed, fixed2)
default:
return false
}
})
// Collect together version ranges that don't need to be separate,
// e.g:
// [ {Introduced: 1.1.0}, {Fixed: 1.2.0} ] becomes
// [ {Introduced: 1.1.0, Fixed: 1.2.0} ].
for i := 0; i < len(m.Versions); i++ {
if i != 0 {
current, prev := m.Versions[i], m.Versions[i-1]
if (prev.Introduced != "" && prev.Fixed == "") &&
(current.Introduced == "" && current.Fixed != "") {
m.Versions[i-1].Fixed = current.Fixed
m.Versions = append(m.Versions[:i], m.Versions[i+1:]...)
i--
}
}
}
m.fixVulnerableAt(pc)
}
func (m *Module) fixVulnerableAt(pc *proxy.Client) {
if m.VulnerableAt != "" {
return
}
// Don't attempt to guess if the given version ranges don't make sense.
if err := checkModVersions(m.Module, m.Versions, pc); err != nil {
return
}
v, err := m.guessVulnerableAt(pc)
if err != nil {
return
}
m.VulnerableAt = v
}
// guessVulnerableAt attempts to find a vulnerable_at
// version using the module proxy, assuming that the version ranges
// have already been validated.
// If there is no fix, the latest version is used.
func (m *Module) guessVulnerableAt(pc *proxy.Client) (v string, err error) {
if m.IsFirstParty() {
return "", errors.New("cannot auto-guess vulnerable_at for first-party modules")
}
// Find the last fixed version, assuming the version ranges are sorted.
fixed := ""
if len(m.Versions) > 0 {
fixed = m.Versions[len(m.Versions)-1].Fixed
}
// If there is no fix, find the latest version of the module.
if fixed == "" {
latest, err := pc.Latest(m.Module)
if err != nil || latest == "" {
return "", fmt.Errorf("no fix, but could not find latest version from proxy: %s", err)
}
return latest, nil
}
// If the latest fixed version is a 0.0.0 pseudo-version, or not a valid version,
// don't attempt to determine the vulnerable_at version.
if !version.IsValid(fixed) {
return "", errors.New("cannot auto-guess when fixed version is invalid")
}
if strings.HasPrefix(fixed, "0.0.0-") {
return "", errors.New("cannot auto-guess when fixed version is 0.0.0 pseudo-version")
}
// Otherwise, find the version right before the fixed version.
vs, err := pc.Versions(m.Module)
if err != nil {
return "", fmt.Errorf("could not find versions from proxy: %s", err)
}
for i := len(vs) - 1; i >= 0; i-- {
if version.Before(vs[i], fixed) {
return vs[i], nil
}
}
return "", errors.New("could not find tagged version less than fixed")
}
// fixLineLength returns a copy of s with all lines trimmed to <=n characters
// (with the exception of single-word lines).
// It preserves paragraph breaks (indicated by "\n\n") and markdown-style list
// breaks.
func fixLineLength(s string, n int) string {
var result strings.Builder
result.Grow(len(s))
for i, paragraph := range strings.Split(toParagraphs(s), "\n\n") {
if i > 0 {
result.WriteString("\n\n")
}
var lines []string
for _, forcedLine := range strings.Split(paragraph, "\n") {
words := strings.Split(forcedLine, " ")
start, length := 0, 0
for k, word := range words {
newLength := length + len(word)
if length > 0 {
newLength++ // space character
}
if newLength <= n {
length = newLength
continue
}
// Adding the word would put the line over the max length,
// so add the line as is (if it is non-empty).
if length > 0 {
lines = append(lines, strings.Join(words[start:k], " "))
}
// Begin a new line with just the word.
start, length = k, len(word)
}
// Add the last line.
if length > 0 {
lines = append(lines, strings.Join(words[start:], " "))
}
}
result.WriteString(strings.Join(lines, "\n"))
}
return result.String()
}
var urlReplacements = []struct {
re *regexp.Regexp
repl string
}{{
regexp.MustCompile(`golang.org`),
`go.dev`,
}, {
regexp.MustCompile(`https?://groups.google.com/forum/\#\![^/]*/([^/]+)/([^/]+)/(.*)`),
`https://groups.google.com/g/$1/c/$2/m/$3`,
}, {
regexp.MustCompile(`.*github.com/golang/go/issues`),
`https://go.dev/issue`,
}, {
regexp.MustCompile(`.*github.com/golang/go/commit`),
`https://go.googlesource.com/+`,
},
}
func fixURL(u string) string {
for _, repl := range urlReplacements {
u = repl.re.ReplaceAllString(u, repl.repl)
}
return u
}