github.com/kastenhq/syft@v0.0.0-20230821225854-0710af25cdbe/syft/pkg/cataloger/rpm/parse_rpm_db.go (about)

     1  package rpm
     2  
     3  import (
     4  	"fmt"
     5  	"io"
     6  	"os"
     7  
     8  	rpmdb "github.com/knqyf263/go-rpmdb/pkg"
     9  
    10  	"github.com/kastenhq/syft/internal"
    11  	"github.com/kastenhq/syft/internal/log"
    12  	"github.com/kastenhq/syft/syft/artifact"
    13  	"github.com/kastenhq/syft/syft/file"
    14  	"github.com/kastenhq/syft/syft/linux"
    15  	"github.com/kastenhq/syft/syft/pkg"
    16  	"github.com/kastenhq/syft/syft/pkg/cataloger/generic"
    17  )
    18  
    19  // parseRpmDb parses an "Packages" RPM DB and returns the Packages listed within it.
    20  func parseRpmDB(resolver file.Resolver, env *generic.Environment, reader file.LocationReadCloser) ([]pkg.Package, []artifact.Relationship, error) {
    21  	f, err := os.CreateTemp("", internal.ApplicationName+"-rpmdb")
    22  	if err != nil {
    23  		return nil, nil, fmt.Errorf("failed to create temp rpmdb file: %w", err)
    24  	}
    25  
    26  	defer func() {
    27  		err = os.Remove(f.Name())
    28  		if err != nil {
    29  			log.Errorf("failed to remove temp rpmdb file: %+v", err)
    30  		}
    31  	}()
    32  
    33  	_, err = io.Copy(f, reader)
    34  	if err != nil {
    35  		return nil, nil, fmt.Errorf("failed to copy rpmdb contents to temp file: %w", err)
    36  	}
    37  
    38  	db, err := rpmdb.Open(f.Name())
    39  	if err != nil {
    40  		return nil, nil, err
    41  	}
    42  
    43  	pkgList, err := db.ListPackages()
    44  	if err != nil {
    45  		return nil, nil, err
    46  	}
    47  
    48  	var allPkgs []pkg.Package
    49  
    50  	var distro *linux.Release
    51  	if env != nil {
    52  		distro = env.LinuxRelease
    53  	}
    54  
    55  	for _, entry := range pkgList {
    56  		if entry == nil {
    57  			continue
    58  		}
    59  
    60  		p := newPackage(
    61  			reader.Location,
    62  			newParsedDataFromEntry(reader.Location, *entry, extractRpmdbFileRecords(resolver, *entry)),
    63  			distro,
    64  		)
    65  
    66  		if !pkg.IsValid(&p) {
    67  			log.WithFields("location", reader.RealPath, "pkg", fmt.Sprintf("%s@%s", entry.Name, entry.Version)).
    68  				Warn("ignoring invalid package found in RPM DB")
    69  			continue
    70  		}
    71  
    72  		p.SetID()
    73  		allPkgs = append(allPkgs, p)
    74  	}
    75  
    76  	return allPkgs, nil, nil
    77  }
    78  
    79  // The RPM naming scheme is [name]-[version]-[release]-[arch], where version is implicitly expands to [epoch]:[version].
    80  // RPM version comparison depends on comparing at least the version and release fields together as a subset of the
    81  // naming scheme. This toELVersion function takes a RPM DB package information and converts it into a minimally comparable
    82  // version string, containing epoch (optional), version, and release information. Epoch is an optional field and can be
    83  // assumed to be 0 when not provided for comparison purposes, however, if the underlying RPM DB entry does not have
    84  // an epoch specified it would be slightly disingenuous to display a value of 0.
    85  func toELVersion(metadata pkg.RpmMetadata) string {
    86  	if metadata.Epoch != nil {
    87  		return fmt.Sprintf("%d:%s-%s", *metadata.Epoch, metadata.Version, metadata.Release)
    88  	}
    89  	return fmt.Sprintf("%s-%s", metadata.Version, metadata.Release)
    90  }
    91  
    92  func extractRpmdbFileRecords(resolver file.PathResolver, entry rpmdb.PackageInfo) []pkg.RpmdbFileRecord {
    93  	var records = make([]pkg.RpmdbFileRecord, 0)
    94  
    95  	files, err := entry.InstalledFiles()
    96  	if err != nil {
    97  		log.Warnf("unable to parse listing of installed files for RPM DB entry: %s", err.Error())
    98  		return records
    99  	}
   100  
   101  	for _, record := range files {
   102  		// only persist RPMDB file records which exist in the image/directory, otherwise ignore them
   103  		if resolver.HasPath(record.Path) {
   104  			records = append(records, pkg.RpmdbFileRecord{
   105  				Path: record.Path,
   106  				Mode: pkg.RpmdbFileMode(record.Mode),
   107  				Size: int(record.Size),
   108  				Digest: file.Digest{
   109  					Value:     record.Digest,
   110  					Algorithm: entry.DigestAlgorithm.String(),
   111  				},
   112  				UserName:  record.Username,
   113  				GroupName: record.Groupname,
   114  				Flags:     record.Flags.String(),
   115  			})
   116  		}
   117  	}
   118  	return records
   119  }