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-rw-r--r--vendor/github.com/moby/sys/user/user.go605
1 files changed, 605 insertions, 0 deletions
diff --git a/vendor/github.com/moby/sys/user/user.go b/vendor/github.com/moby/sys/user/user.go
new file mode 100644
index 0000000..984466d
--- /dev/null
+++ b/vendor/github.com/moby/sys/user/user.go
@@ -0,0 +1,605 @@
+package user
+
+import (
+ "bufio"
+ "bytes"
+ "errors"
+ "fmt"
+ "io"
+ "os"
+ "strconv"
+ "strings"
+)
+
+const (
+ minID = 0
+ maxID = 1<<31 - 1 // for 32-bit systems compatibility
+)
+
+var (
+ // ErrNoPasswdEntries is returned if no matching entries were found in /etc/group.
+ ErrNoPasswdEntries = errors.New("no matching entries in passwd file")
+ // ErrNoGroupEntries is returned if no matching entries were found in /etc/passwd.
+ ErrNoGroupEntries = errors.New("no matching entries in group file")
+ // ErrRange is returned if a UID or GID is outside of the valid range.
+ ErrRange = fmt.Errorf("uids and gids must be in range %d-%d", minID, maxID)
+)
+
+type User struct {
+ Name string
+ Pass string
+ Uid int
+ Gid int
+ Gecos string
+ Home string
+ Shell string
+}
+
+type Group struct {
+ Name string
+ Pass string
+ Gid int
+ List []string
+}
+
+// SubID represents an entry in /etc/sub{u,g}id
+type SubID struct {
+ Name string
+ SubID int64
+ Count int64
+}
+
+// IDMap represents an entry in /proc/PID/{u,g}id_map
+type IDMap struct {
+ ID int64
+ ParentID int64
+ Count int64
+}
+
+func parseLine(line []byte, v ...interface{}) {
+ parseParts(bytes.Split(line, []byte(":")), v...)
+}
+
+func parseParts(parts [][]byte, v ...interface{}) {
+ if len(parts) == 0 {
+ return
+ }
+
+ for i, p := range parts {
+ // Ignore cases where we don't have enough fields to populate the arguments.
+ // Some configuration files like to misbehave.
+ if len(v) <= i {
+ break
+ }
+
+ // Use the type of the argument to figure out how to parse it, scanf() style.
+ // This is legit.
+ switch e := v[i].(type) {
+ case *string:
+ *e = string(p)
+ case *int:
+ // "numbers", with conversion errors ignored because of some misbehaving configuration files.
+ *e, _ = strconv.Atoi(string(p))
+ case *int64:
+ *e, _ = strconv.ParseInt(string(p), 10, 64)
+ case *[]string:
+ // Comma-separated lists.
+ if len(p) != 0 {
+ *e = strings.Split(string(p), ",")
+ } else {
+ *e = []string{}
+ }
+ default:
+ // Someone goof'd when writing code using this function. Scream so they can hear us.
+ panic(fmt.Sprintf("parseLine only accepts {*string, *int, *int64, *[]string} as arguments! %#v is not a pointer!", e))
+ }
+ }
+}
+
+func ParsePasswdFile(path string) ([]User, error) {
+ passwd, err := os.Open(path)
+ if err != nil {
+ return nil, err
+ }
+ defer passwd.Close()
+ return ParsePasswd(passwd)
+}
+
+func ParsePasswd(passwd io.Reader) ([]User, error) {
+ return ParsePasswdFilter(passwd, nil)
+}
+
+func ParsePasswdFileFilter(path string, filter func(User) bool) ([]User, error) {
+ passwd, err := os.Open(path)
+ if err != nil {
+ return nil, err
+ }
+ defer passwd.Close()
+ return ParsePasswdFilter(passwd, filter)
+}
+
+func ParsePasswdFilter(r io.Reader, filter func(User) bool) ([]User, error) {
+ if r == nil {
+ return nil, errors.New("nil source for passwd-formatted data")
+ }
+
+ var (
+ s = bufio.NewScanner(r)
+ out = []User{}
+ )
+
+ for s.Scan() {
+ line := bytes.TrimSpace(s.Bytes())
+ if len(line) == 0 {
+ continue
+ }
+
+ // see: man 5 passwd
+ // name:password:UID:GID:GECOS:directory:shell
+ // Name:Pass:Uid:Gid:Gecos:Home:Shell
+ // root:x:0:0:root:/root:/bin/bash
+ // adm:x:3:4:adm:/var/adm:/bin/false
+ p := User{}
+ parseLine(line, &p.Name, &p.Pass, &p.Uid, &p.Gid, &p.Gecos, &p.Home, &p.Shell)
+
+ if filter == nil || filter(p) {
+ out = append(out, p)
+ }
+ }
+ if err := s.Err(); err != nil {
+ return nil, err
+ }
+
+ return out, nil
+}
+
+func ParseGroupFile(path string) ([]Group, error) {
+ group, err := os.Open(path)
+ if err != nil {
+ return nil, err
+ }
+
+ defer group.Close()
+ return ParseGroup(group)
+}
+
+func ParseGroup(group io.Reader) ([]Group, error) {
+ return ParseGroupFilter(group, nil)
+}
+
+func ParseGroupFileFilter(path string, filter func(Group) bool) ([]Group, error) {
+ group, err := os.Open(path)
+ if err != nil {
+ return nil, err
+ }
+ defer group.Close()
+ return ParseGroupFilter(group, filter)
+}
+
+func ParseGroupFilter(r io.Reader, filter func(Group) bool) ([]Group, error) {
+ if r == nil {
+ return nil, errors.New("nil source for group-formatted data")
+ }
+ rd := bufio.NewReader(r)
+ out := []Group{}
+
+ // Read the file line-by-line.
+ for {
+ var (
+ isPrefix bool
+ wholeLine []byte
+ err error
+ )
+
+ // Read the next line. We do so in chunks (as much as reader's
+ // buffer is able to keep), check if we read enough columns
+ // already on each step and store final result in wholeLine.
+ for {
+ var line []byte
+ line, isPrefix, err = rd.ReadLine()
+
+ if err != nil {
+ // We should return no error if EOF is reached
+ // without a match.
+ if err == io.EOF {
+ err = nil
+ }
+ return out, err
+ }
+
+ // Simple common case: line is short enough to fit in a
+ // single reader's buffer.
+ if !isPrefix && len(wholeLine) == 0 {
+ wholeLine = line
+ break
+ }
+
+ wholeLine = append(wholeLine, line...)
+
+ // Check if we read the whole line already.
+ if !isPrefix {
+ break
+ }
+ }
+
+ // There's no spec for /etc/passwd or /etc/group, but we try to follow
+ // the same rules as the glibc parser, which allows comments and blank
+ // space at the beginning of a line.
+ wholeLine = bytes.TrimSpace(wholeLine)
+ if len(wholeLine) == 0 || wholeLine[0] == '#' {
+ continue
+ }
+
+ // see: man 5 group
+ // group_name:password:GID:user_list
+ // Name:Pass:Gid:List
+ // root:x:0:root
+ // adm:x:4:root,adm,daemon
+ p := Group{}
+ parseLine(wholeLine, &p.Name, &p.Pass, &p.Gid, &p.List)
+
+ if filter == nil || filter(p) {
+ out = append(out, p)
+ }
+ }
+}
+
+type ExecUser struct {
+ Uid int
+ Gid int
+ Sgids []int
+ Home string
+}
+
+// GetExecUserPath is a wrapper for GetExecUser. It reads data from each of the
+// given file paths and uses that data as the arguments to GetExecUser. If the
+// files cannot be opened for any reason, the error is ignored and a nil
+// io.Reader is passed instead.
+func GetExecUserPath(userSpec string, defaults *ExecUser, passwdPath, groupPath string) (*ExecUser, error) {
+ var passwd, group io.Reader
+
+ if passwdFile, err := os.Open(passwdPath); err == nil {
+ passwd = passwdFile
+ defer passwdFile.Close()
+ }
+
+ if groupFile, err := os.Open(groupPath); err == nil {
+ group = groupFile
+ defer groupFile.Close()
+ }
+
+ return GetExecUser(userSpec, defaults, passwd, group)
+}
+
+// GetExecUser parses a user specification string (using the passwd and group
+// readers as sources for /etc/passwd and /etc/group data, respectively). In
+// the case of blank fields or missing data from the sources, the values in
+// defaults is used.
+//
+// GetExecUser will return an error if a user or group literal could not be
+// found in any entry in passwd and group respectively.
+//
+// Examples of valid user specifications are:
+// - ""
+// - "user"
+// - "uid"
+// - "user:group"
+// - "uid:gid
+// - "user:gid"
+// - "uid:group"
+//
+// It should be noted that if you specify a numeric user or group id, they will
+// not be evaluated as usernames (only the metadata will be filled). So attempting
+// to parse a user with user.Name = "1337" will produce the user with a UID of
+// 1337.
+func GetExecUser(userSpec string, defaults *ExecUser, passwd, group io.Reader) (*ExecUser, error) {
+ if defaults == nil {
+ defaults = new(ExecUser)
+ }
+
+ // Copy over defaults.
+ user := &ExecUser{
+ Uid: defaults.Uid,
+ Gid: defaults.Gid,
+ Sgids: defaults.Sgids,
+ Home: defaults.Home,
+ }
+
+ // Sgids slice *cannot* be nil.
+ if user.Sgids == nil {
+ user.Sgids = []int{}
+ }
+
+ // Allow for userArg to have either "user" syntax, or optionally "user:group" syntax
+ var userArg, groupArg string
+ parseLine([]byte(userSpec), &userArg, &groupArg)
+
+ // Convert userArg and groupArg to be numeric, so we don't have to execute
+ // Atoi *twice* for each iteration over lines.
+ uidArg, uidErr := strconv.Atoi(userArg)
+ gidArg, gidErr := strconv.Atoi(groupArg)
+
+ // Find the matching user.
+ users, err := ParsePasswdFilter(passwd, func(u User) bool {
+ if userArg == "" {
+ // Default to current state of the user.
+ return u.Uid == user.Uid
+ }
+
+ if uidErr == nil {
+ // If the userArg is numeric, always treat it as a UID.
+ return uidArg == u.Uid
+ }
+
+ return u.Name == userArg
+ })
+
+ // If we can't find the user, we have to bail.
+ if err != nil && passwd != nil {
+ if userArg == "" {
+ userArg = strconv.Itoa(user.Uid)
+ }
+ return nil, fmt.Errorf("unable to find user %s: %w", userArg, err)
+ }
+
+ var matchedUserName string
+ if len(users) > 0 {
+ // First match wins, even if there's more than one matching entry.
+ matchedUserName = users[0].Name
+ user.Uid = users[0].Uid
+ user.Gid = users[0].Gid
+ user.Home = users[0].Home
+ } else if userArg != "" {
+ // If we can't find a user with the given username, the only other valid
+ // option is if it's a numeric username with no associated entry in passwd.
+
+ if uidErr != nil {
+ // Not numeric.
+ return nil, fmt.Errorf("unable to find user %s: %w", userArg, ErrNoPasswdEntries)
+ }
+ user.Uid = uidArg
+
+ // Must be inside valid uid range.
+ if user.Uid < minID || user.Uid > maxID {
+ return nil, ErrRange
+ }
+
+ // Okay, so it's numeric. We can just roll with this.
+ }
+
+ // On to the groups. If we matched a username, we need to do this because of
+ // the supplementary group IDs.
+ if groupArg != "" || matchedUserName != "" {
+ groups, err := ParseGroupFilter(group, func(g Group) bool {
+ // If the group argument isn't explicit, we'll just search for it.
+ if groupArg == "" {
+ // Check if user is a member of this group.
+ for _, u := range g.List {
+ if u == matchedUserName {
+ return true
+ }
+ }
+ return false
+ }
+
+ if gidErr == nil {
+ // If the groupArg is numeric, always treat it as a GID.
+ return gidArg == g.Gid
+ }
+
+ return g.Name == groupArg
+ })
+ if err != nil && group != nil {
+ return nil, fmt.Errorf("unable to find groups for spec %v: %w", matchedUserName, err)
+ }
+
+ // Only start modifying user.Gid if it is in explicit form.
+ if groupArg != "" {
+ if len(groups) > 0 {
+ // First match wins, even if there's more than one matching entry.
+ user.Gid = groups[0].Gid
+ } else {
+ // If we can't find a group with the given name, the only other valid
+ // option is if it's a numeric group name with no associated entry in group.
+
+ if gidErr != nil {
+ // Not numeric.
+ return nil, fmt.Errorf("unable to find group %s: %w", groupArg, ErrNoGroupEntries)
+ }
+ user.Gid = gidArg
+
+ // Must be inside valid gid range.
+ if user.Gid < minID || user.Gid > maxID {
+ return nil, ErrRange
+ }
+
+ // Okay, so it's numeric. We can just roll with this.
+ }
+ } else if len(groups) > 0 {
+ // Supplementary group ids only make sense if in the implicit form.
+ user.Sgids = make([]int, len(groups))
+ for i, group := range groups {
+ user.Sgids[i] = group.Gid
+ }
+ }
+ }
+
+ return user, nil
+}
+
+// GetAdditionalGroups looks up a list of groups by name or group id
+// against the given /etc/group formatted data. If a group name cannot
+// be found, an error will be returned. If a group id cannot be found,
+// or the given group data is nil, the id will be returned as-is
+// provided it is in the legal range.
+func GetAdditionalGroups(additionalGroups []string, group io.Reader) ([]int, error) {
+ groups := []Group{}
+ if group != nil {
+ var err error
+ groups, err = ParseGroupFilter(group, func(g Group) bool {
+ for _, ag := range additionalGroups {
+ if g.Name == ag || strconv.Itoa(g.Gid) == ag {
+ return true
+ }
+ }
+ return false
+ })
+ if err != nil {
+ return nil, fmt.Errorf("Unable to find additional groups %v: %w", additionalGroups, err)
+ }
+ }
+
+ gidMap := make(map[int]struct{})
+ for _, ag := range additionalGroups {
+ var found bool
+ for _, g := range groups {
+ // if we found a matched group either by name or gid, take the
+ // first matched as correct
+ if g.Name == ag || strconv.Itoa(g.Gid) == ag {
+ if _, ok := gidMap[g.Gid]; !ok {
+ gidMap[g.Gid] = struct{}{}
+ found = true
+ break
+ }
+ }
+ }
+ // we asked for a group but didn't find it. let's check to see
+ // if we wanted a numeric group
+ if !found {
+ gid, err := strconv.ParseInt(ag, 10, 64)
+ if err != nil {
+ // Not a numeric ID either.
+ return nil, fmt.Errorf("Unable to find group %s: %w", ag, ErrNoGroupEntries)
+ }
+ // Ensure gid is inside gid range.
+ if gid < minID || gid > maxID {
+ return nil, ErrRange
+ }
+ gidMap[int(gid)] = struct{}{}
+ }
+ }
+ gids := []int{}
+ for gid := range gidMap {
+ gids = append(gids, gid)
+ }
+ return gids, nil
+}
+
+// GetAdditionalGroupsPath is a wrapper around GetAdditionalGroups
+// that opens the groupPath given and gives it as an argument to
+// GetAdditionalGroups.
+func GetAdditionalGroupsPath(additionalGroups []string, groupPath string) ([]int, error) {
+ var group io.Reader
+
+ if groupFile, err := os.Open(groupPath); err == nil {
+ group = groupFile
+ defer groupFile.Close()
+ }
+ return GetAdditionalGroups(additionalGroups, group)
+}
+
+func ParseSubIDFile(path string) ([]SubID, error) {
+ subid, err := os.Open(path)
+ if err != nil {
+ return nil, err
+ }
+ defer subid.Close()
+ return ParseSubID(subid)
+}
+
+func ParseSubID(subid io.Reader) ([]SubID, error) {
+ return ParseSubIDFilter(subid, nil)
+}
+
+func ParseSubIDFileFilter(path string, filter func(SubID) bool) ([]SubID, error) {
+ subid, err := os.Open(path)
+ if err != nil {
+ return nil, err
+ }
+ defer subid.Close()
+ return ParseSubIDFilter(subid, filter)
+}
+
+func ParseSubIDFilter(r io.Reader, filter func(SubID) bool) ([]SubID, error) {
+ if r == nil {
+ return nil, errors.New("nil source for subid-formatted data")
+ }
+
+ var (
+ s = bufio.NewScanner(r)
+ out = []SubID{}
+ )
+
+ for s.Scan() {
+ line := bytes.TrimSpace(s.Bytes())
+ if len(line) == 0 {
+ continue
+ }
+
+ // see: man 5 subuid
+ p := SubID{}
+ parseLine(line, &p.Name, &p.SubID, &p.Count)
+
+ if filter == nil || filter(p) {
+ out = append(out, p)
+ }
+ }
+ if err := s.Err(); err != nil {
+ return nil, err
+ }
+
+ return out, nil
+}
+
+func ParseIDMapFile(path string) ([]IDMap, error) {
+ r, err := os.Open(path)
+ if err != nil {
+ return nil, err
+ }
+ defer r.Close()
+ return ParseIDMap(r)
+}
+
+func ParseIDMap(r io.Reader) ([]IDMap, error) {
+ return ParseIDMapFilter(r, nil)
+}
+
+func ParseIDMapFileFilter(path string, filter func(IDMap) bool) ([]IDMap, error) {
+ r, err := os.Open(path)
+ if err != nil {
+ return nil, err
+ }
+ defer r.Close()
+ return ParseIDMapFilter(r, filter)
+}
+
+func ParseIDMapFilter(r io.Reader, filter func(IDMap) bool) ([]IDMap, error) {
+ if r == nil {
+ return nil, errors.New("nil source for idmap-formatted data")
+ }
+
+ var (
+ s = bufio.NewScanner(r)
+ out = []IDMap{}
+ )
+
+ for s.Scan() {
+ line := bytes.TrimSpace(s.Bytes())
+ if len(line) == 0 {
+ continue
+ }
+
+ // see: man 7 user_namespaces
+ p := IDMap{}
+ parseParts(bytes.Fields(line), &p.ID, &p.ParentID, &p.Count)
+
+ if filter == nil || filter(p) {
+ out = append(out, p)
+ }
+ }
+ if err := s.Err(); err != nil {
+ return nil, err
+ }
+
+ return out, nil
+}
generated by cgit v1.2.3 (git 2.39.1) at 2026-02-03 09:21:57 +0000