| 1 | package host |
| 2 | |
| 3 | import ( |
| 4 | "context" |
| 5 | "os" |
| 6 | "strings" |
| 7 | "time" |
| 8 | |
| 9 | "github.com/carlosframework/platform/internal/instancectl" |
| 10 | "github.com/carlosframework/platform/internal/rootstate" |
| 11 | ) |
| 12 | |
| 13 | type claimPredecessorKernel struct { |
| 14 | ctl func(context.Context, ...string) (string, error) |
| 15 | boot func() (string, error) |
| 16 | group func(string) (rootstate.FileIdentity, bool, error) |
| 17 | } |
| 18 | |
| 19 | func (k claimPredecessorKernel) show(ctx context.Context, unit string) (map[string]string, error) { |
| 20 | if k.ctl == nil || k.group == nil || !instancectl.ValidBoundClaimUnit(unit) { |
| 21 | return nil, os.ErrPermission |
| 22 | } |
| 23 | out, err := k.ctl(ctx, "show", "-p", "ActiveState,InvocationID,ControlGroup,FragmentPath,DropInPaths", unit) |
| 24 | if err != nil { |
| 25 | return nil, err |
| 26 | } |
| 27 | props := map[string]string{} |
| 28 | for _, line := range strings.Split(out, "\n") { |
| 29 | if key, value, ok := strings.Cut(line, "="); ok { |
| 30 | if _, exists := props[key]; exists { |
| 31 | return nil, os.ErrPermission |
| 32 | } |
| 33 | props[key] = value |
| 34 | } |
| 35 | } |
| 36 | for _, key := range []string{"ActiveState", "InvocationID", "ControlGroup", "FragmentPath", "DropInPaths"} { |
| 37 | if _, ok := props[key]; !ok { |
| 38 | return nil, os.ErrPermission |
| 39 | } |
| 40 | } |
| 41 | return props, nil |
| 42 | } |
| 43 | |
| 44 | func (k claimPredecessorKernel) capture(ctx context.Context, b claimUnitBinding) (claimUnitPredecessor, error) { |
| 45 | var p claimUnitPredecessor |
| 46 | props, err := k.show(ctx, b.Shape.Unit) |
| 47 | if err != nil { |
| 48 | return p, err |
| 49 | } |
| 50 | group := strings.TrimPrefix(props["ControlGroup"], "/") |
| 51 | if props["ActiveState"] != "active" || props["InvocationID"] == "" || !claimPredecessorPlacement(b.Shape.Unit, group) || props["ControlGroup"] != "/"+group || props["FragmentPath"] != "/etc/systemd/system/"+b.Shape.Unit || props["DropInPaths"] != "" { |
| 52 | return p, os.ErrPermission |
| 53 | } |
| 54 | id, populated, err := k.group(group) |
| 55 | if err != nil { |
| 56 | return p, err |
| 57 | } |
| 58 | if !populated || id == (rootstate.FileIdentity{}) { |
| 59 | return p, os.ErrPermission |
| 60 | } |
| 61 | again, err := k.show(ctx, b.Shape.Unit) |
| 62 | if err != nil { |
| 63 | return p, err |
| 64 | } |
| 65 | for key, value := range props { |
| 66 | if again[key] != value { |
| 67 | return p, os.ErrPermission |
| 68 | } |
| 69 | } |
| 70 | boot := "" |
| 71 | if k.boot != nil { |
| 72 | boot, err = k.boot() |
| 73 | if err != nil || boot == "" { |
| 74 | return p, os.ErrPermission |
| 75 | } |
| 76 | } |
| 77 | return claimUnitPredecessor{Unit: b.Shape.Unit, Invocation: props["InvocationID"], Group: group, GroupIdentity: id, Boot: boot}, nil |
| 78 | } |
| 79 | |
| 80 | func (k claimPredecessorKernel) stop(ctx context.Context, p claimUnitPredecessor) error { |
| 81 | if !p.valid(p.Unit) { |
| 82 | return os.ErrPermission |
| 83 | } |
| 84 | ctx, cancel := context.WithTimeout(ctx, 30*time.Second) |
| 85 | defer cancel() |
| 86 | issued := false |
| 87 | for { |
| 88 | props, err := k.show(ctx, p.Unit) |
| 89 | if err != nil { |
| 90 | return err |
| 91 | } |
| 92 | if props["InvocationID"] != "" && props["InvocationID"] != p.Invocation { |
| 93 | return os.ErrPermission |
| 94 | } |
| 95 | id, populated, err := k.group(p.Group) |
| 96 | if err != nil { |
| 97 | return err |
| 98 | } |
| 99 | if k.boot != nil { |
| 100 | boot, e := k.boot() |
| 101 | if e != nil || boot == "" || p.Boot == "" { |
| 102 | return os.ErrPermission |
| 103 | } |
| 104 | if boot != p.Boot { |
| 105 | if (props["ActiveState"] == "inactive" || props["ActiveState"] == "failed") && !populated { |
| 106 | return nil |
| 107 | } |
| 108 | return os.ErrPermission |
| 109 | } |
| 110 | } |
| 111 | if id != (rootstate.FileIdentity{}) && id != p.GroupIdentity { |
| 112 | return os.ErrPermission |
| 113 | } |
| 114 | idle := props["ActiveState"] == "inactive" || props["ActiveState"] == "failed" |
| 115 | if idle && !populated { |
| 116 | return nil |
| 117 | } |
| 118 | if props["InvocationID"] != p.Invocation || props["ControlGroup"] != "/"+p.Group || id != p.GroupIdentity { |
| 119 | return os.ErrPermission |
| 120 | } |
| 121 | if !issued { |
| 122 | if _, err = k.ctl(ctx, "stop", p.Unit); err != nil { |
| 123 | return err |
| 124 | } |
| 125 | issued = true |
| 126 | continue |
| 127 | } |
| 128 | select { |
| 129 | case <-ctx.Done(): |
| 130 | return ctx.Err() |
| 131 | case <-time.After(25 * time.Millisecond): |
| 132 | } |
| 133 | } |
| 134 | } |
| 135 | |
amadan