clair/worker/detectors/packages/dpkg.go
2015-11-13 14:11:28 -05:00

117 lines
3.8 KiB
Go

// Copyright 2015 clair 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 packages defines PackagesDetector for several sources.
package packages
import (
"bufio"
"regexp"
"strings"
"github.com/coreos/pkg/capnslog"
"github.com/coreos/clair/database"
"github.com/coreos/clair/utils/types"
"github.com/coreos/clair/worker/detectors"
)
var (
log = capnslog.NewPackageLogger("github.com/coreos/clair", "worker/detectors/packages")
dpkgSrcCaptureRegexp = regexp.MustCompile(`Source: (?P<name>[^\s]*)( \((?P<version>.*)\))?`)
dpkgSrcCaptureRegexpNames = dpkgSrcCaptureRegexp.SubexpNames()
)
// DpkgPackagesDetector implements PackagesDetector and detects dpkg packages
type DpkgPackagesDetector struct{}
func init() {
detectors.RegisterPackagesDetector("dpkg", &DpkgPackagesDetector{})
}
// Detect detects packages using var/lib/dpkg/status from the input data
func (detector *DpkgPackagesDetector) Detect(data map[string][]byte) ([]*database.Package, error) {
f, hasFile := data["var/lib/dpkg/status"]
if !hasFile {
return []*database.Package{}, nil
}
// Create a map to store packages and ensure their uniqueness
packagesMap := make(map[string]*database.Package)
var pkg *database.Package
var err error
scanner := bufio.NewScanner(strings.NewReader(string(f)))
for scanner.Scan() {
line := scanner.Text()
if strings.HasPrefix(line, "Package: ") {
// Package line
// Defines the name of the package
pkg = &database.Package{
Name: strings.TrimSpace(strings.TrimPrefix(line, "Package: ")),
}
} else if pkg != nil && strings.HasPrefix(line, "Source: ") {
// Source line (Optionnal)
// Gives the name of the source package
// May also specifies a version
srcCapture := dpkgSrcCaptureRegexp.FindAllStringSubmatch(line, -1)[0]
md := map[string]string{}
for i, n := range srcCapture {
md[dpkgSrcCaptureRegexpNames[i]] = strings.TrimSpace(n)
}
pkg.Name = md["name"]
if md["version"] != "" {
pkg.Version, err = types.NewVersion(md["version"])
if err != nil {
log.Warningf("could not parse package version '%s': %s. skipping", line[1], err.Error())
}
}
} else if pkg != nil && strings.HasPrefix(line, "Version: ") && pkg.Version.String() == "" {
// Version line
// Defines the version of the package
// This version is less important than a version retrieved from a Source line
// because the Debian vulnerabilities often skips the epoch from the Version field
// which is not present in the Source version, and because +bX revisions don't matter
pkg.Version, err = types.NewVersion(strings.TrimPrefix(line, "Version: "))
if err != nil {
log.Warningf("could not parse package version '%s': %s. skipping", line[1], err.Error())
}
}
// Add the package to the result array if we have all the informations
if pkg != nil && pkg.Name != "" && pkg.Version.String() != "" {
packagesMap[pkg.Key()] = pkg
pkg = nil
}
}
// Convert the map to a slice
packages := make([]*database.Package, 0, len(packagesMap))
for _, pkg := range packagesMap {
packages = append(packages, pkg)
}
return packages, nil
}
// GetRequiredFiles returns the list of files required for Detect, without
// leading /
func (detector *DpkgPackagesDetector) GetRequiredFiles() []string {
return []string{"var/lib/dpkg/status"}
}