internal/pkg: encode checksum in ident

This also rearranges the ident ir to be more predictable, and avoids an obvious and somewhat easy to get into inconsistent state.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/pkg/dir_test.go

@@ -76,7 +76,7 @@ func TestFlatten(t *testing.T) {
 			"checksum/fLYGIMHgN1louE-JzITJZJo2SDniPu-IHBXubtvQWFO-hXnDVKNuscV7-zlyr5fU": {Mode: 0400, Data: []byte("\x7f\xe1\x69\xa2\xdd\x63\x96\x26\x83\x79\x61\x8b\xf0\x3f\xd5\x16\x9a\x39\x3a\xdb\xcf\xb1\xbc\x8d\x33\xff\x75\xee\x62\x56\xa9\xf0\x27\xac\x13\x94\x69")},
 
 			"identifier": {Mode: fs.ModeDir | 0700},
-			"identifier/NqVORkT6L9HX6Za7kT2zcibY10qFqBaxEjPiYFrBQX-ZFr3yxCzJxbKOP0zVjeWb": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/fLYGIMHgN1louE-JzITJZJo2SDniPu-IHBXubtvQWFO-hXnDVKNuscV7-zlyr5fU")},
+			"identifier/00BNNr-PsNMtowTpEG86ZeI7eQKoD-pjSCPAal1e5MYqr_N7FLpyXKdXLXE8WEBF": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/fLYGIMHgN1louE-JzITJZJo2SDniPu-IHBXubtvQWFO-hXnDVKNuscV7-zlyr5fU")},
 
 			"work": {Mode: fs.ModeDir | 0700},
 		}, []pkg.FlatEntry{
@@ -86,10 +86,10 @@ func TestFlatten(t *testing.T) {
 			{Mode: 0400, Path: "checksum/fLYGIMHgN1louE-JzITJZJo2SDniPu-IHBXubtvQWFO-hXnDVKNuscV7-zlyr5fU", Data: []byte("\x7f\xe1\x69\xa2\xdd\x63\x96\x26\x83\x79\x61\x8b\xf0\x3f\xd5\x16\x9a\x39\x3a\xdb\xcf\xb1\xbc\x8d\x33\xff\x75\xee\x62\x56\xa9\xf0\x27\xac\x13\x94\x69")},
 
 			{Mode: fs.ModeDir | 0700, Path: "identifier"},
-			{Mode: fs.ModeSymlink | 0777, Path: "identifier/NqVORkT6L9HX6Za7kT2zcibY10qFqBaxEjPiYFrBQX-ZFr3yxCzJxbKOP0zVjeWb", Data: []byte("../checksum/fLYGIMHgN1louE-JzITJZJo2SDniPu-IHBXubtvQWFO-hXnDVKNuscV7-zlyr5fU")},
+			{Mode: fs.ModeSymlink | 0777, Path: "identifier/00BNNr-PsNMtowTpEG86ZeI7eQKoD-pjSCPAal1e5MYqr_N7FLpyXKdXLXE8WEBF", Data: []byte("../checksum/fLYGIMHgN1louE-JzITJZJo2SDniPu-IHBXubtvQWFO-hXnDVKNuscV7-zlyr5fU")},
 
 			{Mode: fs.ModeDir | 0700, Path: "work"},
-		}, pkg.MustDecode("bqtn69RkV5E7V7GhhgCFjcvbxmaqrO8DywamM4Tyjf10F6EJBHjXiIa_tFRtF4iN"), nil},
+		}, pkg.MustDecode("KkdL8x2a84V8iYZop5jSTyba54xSgf_NZ1R0c4nSp9xTdk3SK_zUKGhNJ2uK8wMY"), nil},
 
 		{"sample directory step simple", fstest.MapFS{
 			".": {Mode: fs.ModeDir | 0500},
@@ -208,8 +208,8 @@ func TestFlatten(t *testing.T) {
 			"checksum/cTw0h3AmYe7XudSoyEMByduYXqGi-N5ZkTZ0t9K5elsu3i_jNIVF5T08KR1roBFM/work":                                                                                     {Mode: fs.ModeDir | 0500},
 
 			"identifier": {Mode: fs.ModeDir | 0700},
-			"identifier/-P_1iw6yVq_letMHncqcExSE0bYcDhYI5OdY6b1wKASf-Corufvj__XTBUq2Qd2a": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/cTw0h3AmYe7XudSoyEMByduYXqGi-N5ZkTZ0t9K5elsu3i_jNIVF5T08KR1roBFM")},
+			"identifier/5-NfJKBlUgVhAP_JeCjjo1UxF72x8QVMgeKPWd8s0J-RYvRJy6veTQDwmgxOvr6v": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/cTw0h3AmYe7XudSoyEMByduYXqGi-N5ZkTZ0t9K5elsu3i_jNIVF5T08KR1roBFM")},
-			"identifier/0_rRxIqbX9LK9L_KDbuafotFz6HFkonNgO9gXhK1asM_Y1Pxn0amg756vRTo6m74": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/cTw0h3AmYe7XudSoyEMByduYXqGi-N5ZkTZ0t9K5elsu3i_jNIVF5T08KR1roBFM")},
+			"identifier/VWakDFDSjNMvdzwxG0Y1IKFdCzExgiQnjg-vv2srsZObwh-5WOJx7H5HtCgDXHcq": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/cTw0h3AmYe7XudSoyEMByduYXqGi-N5ZkTZ0t9K5elsu3i_jNIVF5T08KR1roBFM")},
 
 			"temp": {Mode: fs.ModeDir | 0700},
 			"work": {Mode: fs.ModeDir | 0700},
@@ -230,12 +230,12 @@ func TestFlatten(t *testing.T) {
 			{Mode: fs.ModeDir | 0500, Path: "checksum/cTw0h3AmYe7XudSoyEMByduYXqGi-N5ZkTZ0t9K5elsu3i_jNIVF5T08KR1roBFM/work"},
 
 			{Mode: fs.ModeDir | 0700, Path: "identifier"},
-			{Mode: fs.ModeSymlink | 0777, Path: "identifier/-P_1iw6yVq_letMHncqcExSE0bYcDhYI5OdY6b1wKASf-Corufvj__XTBUq2Qd2a", Data: []byte("../checksum/cTw0h3AmYe7XudSoyEMByduYXqGi-N5ZkTZ0t9K5elsu3i_jNIVF5T08KR1roBFM")},
+			{Mode: fs.ModeSymlink | 0777, Path: "identifier/5-NfJKBlUgVhAP_JeCjjo1UxF72x8QVMgeKPWd8s0J-RYvRJy6veTQDwmgxOvr6v", Data: []byte("../checksum/cTw0h3AmYe7XudSoyEMByduYXqGi-N5ZkTZ0t9K5elsu3i_jNIVF5T08KR1roBFM")},
-			{Mode: fs.ModeSymlink | 0777, Path: "identifier/0_rRxIqbX9LK9L_KDbuafotFz6HFkonNgO9gXhK1asM_Y1Pxn0amg756vRTo6m74", Data: []byte("../checksum/cTw0h3AmYe7XudSoyEMByduYXqGi-N5ZkTZ0t9K5elsu3i_jNIVF5T08KR1roBFM")},
+			{Mode: fs.ModeSymlink | 0777, Path: "identifier/VWakDFDSjNMvdzwxG0Y1IKFdCzExgiQnjg-vv2srsZObwh-5WOJx7H5HtCgDXHcq", Data: []byte("../checksum/cTw0h3AmYe7XudSoyEMByduYXqGi-N5ZkTZ0t9K5elsu3i_jNIVF5T08KR1roBFM")},
 
 			{Mode: fs.ModeDir | 0700, Path: "temp"},
 			{Mode: fs.ModeDir | 0700, Path: "work"},
-		}, pkg.MustDecode("sxbgyX-bPoezbha214n2lbQhiVfTUBkhZ0EX6zI7mmkMdrCdwuMwhMBJphLQsy94"), nil},
+		}, pkg.MustDecode("nnOiyjjjvgZChsGtO4rA1JHckwYBBbxwNfecPJp62OFP6aoYUxHQ5UtYsrDpnwan"), nil},
 
 		{"sample tar expand step unpack", fstest.MapFS{
 			".": {Mode: fs.ModeDir | 0500},
@@ -255,8 +255,8 @@ func TestFlatten(t *testing.T) {
 			"checksum/CH3AiUrCCcVOjOYLaMKKK1Da78989JtfHeIsxMzWOQFiN4mrCLDYpoDxLWqJWCUN/libedac.so": {Mode: fs.ModeSymlink | 0777, Data: []byte("/proc/nonexistent/libedac.so")},
 
 			"identifier": {Mode: fs.ModeDir | 0700},
-			"identifier/-P_1iw6yVq_letMHncqcExSE0bYcDhYI5OdY6b1wKASf-Corufvj__XTBUq2Qd2a": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/CH3AiUrCCcVOjOYLaMKKK1Da78989JtfHeIsxMzWOQFiN4mrCLDYpoDxLWqJWCUN")},
+			"identifier/VWakDFDSjNMvdzwxG0Y1IKFdCzExgiQnjg-vv2srsZObwh-5WOJx7H5HtCgDXHcq": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/CH3AiUrCCcVOjOYLaMKKK1Da78989JtfHeIsxMzWOQFiN4mrCLDYpoDxLWqJWCUN")},
-			"identifier/0_rRxIqbX9LK9L_KDbuafotFz6HFkonNgO9gXhK1asM_Y1Pxn0amg756vRTo6m74": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/CH3AiUrCCcVOjOYLaMKKK1Da78989JtfHeIsxMzWOQFiN4mrCLDYpoDxLWqJWCUN")},
+			"identifier/v3z1m-ofUqJz4_rasXRlTw5NgKk63RLvd5JKBpDeiNaYiUKSGN5KJbJGJHMt7cTf": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/CH3AiUrCCcVOjOYLaMKKK1Da78989JtfHeIsxMzWOQFiN4mrCLDYpoDxLWqJWCUN")},
 
 			"temp": {Mode: fs.ModeDir | 0700},
 			"work": {Mode: fs.ModeDir | 0700},
@@ -268,12 +268,12 @@ func TestFlatten(t *testing.T) {
 			{Mode: fs.ModeSymlink | 0777, Path: "checksum/CH3AiUrCCcVOjOYLaMKKK1Da78989JtfHeIsxMzWOQFiN4mrCLDYpoDxLWqJWCUN/libedac.so", Data: []byte("/proc/nonexistent/libedac.so")},
 
 			{Mode: fs.ModeDir | 0700, Path: "identifier"},
-			{Mode: fs.ModeSymlink | 0777, Path: "identifier/-P_1iw6yVq_letMHncqcExSE0bYcDhYI5OdY6b1wKASf-Corufvj__XTBUq2Qd2a", Data: []byte("../checksum/CH3AiUrCCcVOjOYLaMKKK1Da78989JtfHeIsxMzWOQFiN4mrCLDYpoDxLWqJWCUN")},
+			{Mode: fs.ModeSymlink | 0777, Path: "identifier/VWakDFDSjNMvdzwxG0Y1IKFdCzExgiQnjg-vv2srsZObwh-5WOJx7H5HtCgDXHcq", Data: []byte("../checksum/CH3AiUrCCcVOjOYLaMKKK1Da78989JtfHeIsxMzWOQFiN4mrCLDYpoDxLWqJWCUN")},
-			{Mode: fs.ModeSymlink | 0777, Path: "identifier/0_rRxIqbX9LK9L_KDbuafotFz6HFkonNgO9gXhK1asM_Y1Pxn0amg756vRTo6m74", Data: []byte("../checksum/CH3AiUrCCcVOjOYLaMKKK1Da78989JtfHeIsxMzWOQFiN4mrCLDYpoDxLWqJWCUN")},
+			{Mode: fs.ModeSymlink | 0777, Path: "identifier/v3z1m-ofUqJz4_rasXRlTw5NgKk63RLvd5JKBpDeiNaYiUKSGN5KJbJGJHMt7cTf", Data: []byte("../checksum/CH3AiUrCCcVOjOYLaMKKK1Da78989JtfHeIsxMzWOQFiN4mrCLDYpoDxLWqJWCUN")},
 
 			{Mode: fs.ModeDir | 0700, Path: "temp"},
 			{Mode: fs.ModeDir | 0700, Path: "work"},
-		}, pkg.MustDecode("4I8wx_h7NSJTlG5lbuz-GGEXrOg0GYC3M_503LYEBhv5XGWXfNIdIY9Q3eVSYldX"), nil},
+		}, pkg.MustDecode("bQVH19N7dX50SdQ6JNVYbFdDZV4t8IaM4dhxGvjACpdoEgJ2jZJfYKLH4ya7ZD_s"), nil},
 
 		{"testtool", fstest.MapFS{
 			".": {Mode: fs.ModeDir | 0500},
@@ -295,9 +295,9 @@ func TestFlatten(t *testing.T) {
 			"checksum/OLBgp1GsljhM2TJ-sbHjaiH9txEUvgdDTAzHv2P24donTt6_529l-9Ua0vFImLlb":       {Mode: 0400, Data: []byte{}},
 
 			"identifier": {Mode: fs.ModeDir | 0700},
-			"identifier/U2cbgVgEtjfRuvHfE1cQnZ3t8yoexULQyo_VLgvxAVJSsobMcNaFIsuDWtmt7kzK": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/GPa4aBakdSJd7Tz7LYj_VJFoojzyZinmVcG3k6M5xI6CZ821J5sXLhLDDuS47gi9")},
+			"identifier/LRxdkRYNKnZT6bKiu5W8ATeAAmq3n_5AAJkF6G0EpAOEloiZvADJBkfixgtgF1Z9": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/GPa4aBakdSJd7Tz7LYj_VJFoojzyZinmVcG3k6M5xI6CZ821J5sXLhLDDuS47gi9")},
 			"identifier/_gAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/OLBgp1GsljhM2TJ-sbHjaiH9txEUvgdDTAzHv2P24donTt6_529l-9Ua0vFImLlb")},
-			"identifier/nfeISfLeFDr1k-g3hpE1oZ440kTqDdfF8TDpoLdbTPqaMMIl95oiqcvqjRkMjubA": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			"identifier/cGvuAdKA2tThRa4w3ZI2c5S5TXDx4j2qvfFM7pzf7y5vBz7NisBV06ThBXw_97xK": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
 
 			"temp": {Mode: fs.ModeDir | 0700},
 			"work": {Mode: fs.ModeDir | 0700},
@@ -311,13 +311,13 @@ func TestFlatten(t *testing.T) {
 			{Mode: 0400, Path: "checksum/OLBgp1GsljhM2TJ-sbHjaiH9txEUvgdDTAzHv2P24donTt6_529l-9Ua0vFImLlb", Data: []byte{}},
 
 			{Mode: fs.ModeDir | 0700, Path: "identifier"},
-			{Mode: fs.ModeSymlink | 0777, Path: "identifier/U2cbgVgEtjfRuvHfE1cQnZ3t8yoexULQyo_VLgvxAVJSsobMcNaFIsuDWtmt7kzK", Data: []byte("../checksum/GPa4aBakdSJd7Tz7LYj_VJFoojzyZinmVcG3k6M5xI6CZ821J5sXLhLDDuS47gi9")},
+			{Mode: fs.ModeSymlink | 0777, Path: "identifier/LRxdkRYNKnZT6bKiu5W8ATeAAmq3n_5AAJkF6G0EpAOEloiZvADJBkfixgtgF1Z9", Data: []byte("../checksum/GPa4aBakdSJd7Tz7LYj_VJFoojzyZinmVcG3k6M5xI6CZ821J5sXLhLDDuS47gi9")},
 			{Mode: fs.ModeSymlink | 0777, Path: "identifier/_gAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA", Data: []byte("../checksum/OLBgp1GsljhM2TJ-sbHjaiH9txEUvgdDTAzHv2P24donTt6_529l-9Ua0vFImLlb")},
-			{Mode: fs.ModeSymlink | 0777, Path: "identifier/nfeISfLeFDr1k-g3hpE1oZ440kTqDdfF8TDpoLdbTPqaMMIl95oiqcvqjRkMjubA", Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			{Mode: fs.ModeSymlink | 0777, Path: "identifier/cGvuAdKA2tThRa4w3ZI2c5S5TXDx4j2qvfFM7pzf7y5vBz7NisBV06ThBXw_97xK", Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
 
 			{Mode: fs.ModeDir | 0700, Path: "temp"},
 			{Mode: fs.ModeDir | 0700, Path: "work"},
-		}, pkg.MustDecode("UiV6kMz7KrTsc_yphiyQzFLqjRanHxUOwrBMtkKuWo4mOO6WgPFAcoUEeSp7eVIW"), nil},
+		}, pkg.MustDecode("BQb5SCAo0Rw0YBGqjGemK1jH3jk0cgxAQ-JyeqVRqaqmEevJ3jtXNL8HB470XNnB"), nil},
 
 		{"testtool net", fstest.MapFS{
 			".": {Mode: fs.ModeDir | 0500},
@@ -340,8 +340,8 @@ func TestFlatten(t *testing.T) {
 
 			"identifier": {Mode: fs.ModeDir | 0700},
 			"identifier/_gAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/OLBgp1GsljhM2TJ-sbHjaiH9txEUvgdDTAzHv2P24donTt6_529l-9Ua0vFImLlb")},
-			"identifier/QdsJhGgnk5N2xdUNGcndXQxFKifxf1V_2t9X8CQ-pDcg24x6mGJC_BiLfGbs6Qml": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/a1F_i9PVQI4qMcoHgTQkORuyWLkC1GLIxOhDt2JpU1NGAxWc5VJzdlfRK-PYBh3W")},
+			"identifier/TAspufRsG2I_TsxUUj2b7bUnCHgcVSdh6aOZpzL0W5Bjn4EZmOGzjofaOWd8J11H": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/a1F_i9PVQI4qMcoHgTQkORuyWLkC1GLIxOhDt2JpU1NGAxWc5VJzdlfRK-PYBh3W")},
-			"identifier/nfeISfLeFDr1k-g3hpE1oZ440kTqDdfF8TDpoLdbTPqaMMIl95oiqcvqjRkMjubA": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			"identifier/cGvuAdKA2tThRa4w3ZI2c5S5TXDx4j2qvfFM7pzf7y5vBz7NisBV06ThBXw_97xK": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
 
 			"temp": {Mode: fs.ModeDir | 0700},
 			"work": {Mode: fs.ModeDir | 0700},
@@ -355,13 +355,13 @@ func TestFlatten(t *testing.T) {
 			{Mode: 0400, Path: "checksum/a1F_i9PVQI4qMcoHgTQkORuyWLkC1GLIxOhDt2JpU1NGAxWc5VJzdlfRK-PYBh3W/check", Data: []byte("net")},
 
 			{Mode: fs.ModeDir | 0700, Path: "identifier"},
-			{Mode: fs.ModeSymlink | 0777, Path: "identifier/QdsJhGgnk5N2xdUNGcndXQxFKifxf1V_2t9X8CQ-pDcg24x6mGJC_BiLfGbs6Qml", Data: []byte("../checksum/a1F_i9PVQI4qMcoHgTQkORuyWLkC1GLIxOhDt2JpU1NGAxWc5VJzdlfRK-PYBh3W")},
+			{Mode: fs.ModeSymlink | 0777, Path: "identifier/TAspufRsG2I_TsxUUj2b7bUnCHgcVSdh6aOZpzL0W5Bjn4EZmOGzjofaOWd8J11H", Data: []byte("../checksum/a1F_i9PVQI4qMcoHgTQkORuyWLkC1GLIxOhDt2JpU1NGAxWc5VJzdlfRK-PYBh3W")},
 			{Mode: fs.ModeSymlink | 0777, Path: "identifier/_gAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA", Data: []byte("../checksum/OLBgp1GsljhM2TJ-sbHjaiH9txEUvgdDTAzHv2P24donTt6_529l-9Ua0vFImLlb")},
-			{Mode: fs.ModeSymlink | 0777, Path: "identifier/nfeISfLeFDr1k-g3hpE1oZ440kTqDdfF8TDpoLdbTPqaMMIl95oiqcvqjRkMjubA", Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			{Mode: fs.ModeSymlink | 0777, Path: "identifier/cGvuAdKA2tThRa4w3ZI2c5S5TXDx4j2qvfFM7pzf7y5vBz7NisBV06ThBXw_97xK", Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
 
 			{Mode: fs.ModeDir | 0700, Path: "temp"},
 			{Mode: fs.ModeDir | 0700, Path: "work"},
-		}, pkg.MustDecode("ek4K-0d4iRSArkY2TCs3WK34DbiYeOmhE_4vsJTSu_6roY4ZF3YG6eKRooal-i1o"), nil},
+		}, pkg.MustDecode("hJ7nCMLea_09Z7Fi4ALXOgubMNwK7C61THdQobpQJhH3tnr7PJ86aY98Mte3rBje"), nil},
 
 		{"sample exec container overlay root", fstest.MapFS{
 			".": {Mode: fs.ModeDir | 0700},
@@ -372,8 +372,8 @@ func TestFlatten(t *testing.T) {
 			"checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU":       {Mode: fs.ModeDir | 0500},
 
 			"identifier": {Mode: fs.ModeDir | 0700},
-			"identifier/5ey2wpmMpj483YYa7ZZQciYLA2cx3_l167JCqWW4Pd-5DVp81dj9EsBtVTwYptF6": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/GPa4aBakdSJd7Tz7LYj_VJFoojzyZinmVcG3k6M5xI6CZ821J5sXLhLDDuS47gi9")},
+			"identifier/UB9HPeMgMPJf3Ut4jLWwnCtu_P3Lr29i8Erf084bHe8jjzBMKPDNxQ3RMrirkH6H": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/GPa4aBakdSJd7Tz7LYj_VJFoojzyZinmVcG3k6M5xI6CZ821J5sXLhLDDuS47gi9")},
-			"identifier/nfeISfLeFDr1k-g3hpE1oZ440kTqDdfF8TDpoLdbTPqaMMIl95oiqcvqjRkMjubA": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			"identifier/cGvuAdKA2tThRa4w3ZI2c5S5TXDx4j2qvfFM7pzf7y5vBz7NisBV06ThBXw_97xK": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
 
 			"temp": {Mode: fs.ModeDir | 0700},
 			"work": {Mode: fs.ModeDir | 0700},
@@ -386,12 +386,12 @@ func TestFlatten(t *testing.T) {
 			{Mode: fs.ModeDir | 0500, Path: "checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU"},
 
 			{Mode: fs.ModeDir | 0700, Path: "identifier"},
-			{Mode: fs.ModeSymlink | 0777, Path: "identifier/5ey2wpmMpj483YYa7ZZQciYLA2cx3_l167JCqWW4Pd-5DVp81dj9EsBtVTwYptF6", Data: []byte("../checksum/GPa4aBakdSJd7Tz7LYj_VJFoojzyZinmVcG3k6M5xI6CZ821J5sXLhLDDuS47gi9")},
+			{Mode: fs.ModeSymlink | 0777, Path: "identifier/UB9HPeMgMPJf3Ut4jLWwnCtu_P3Lr29i8Erf084bHe8jjzBMKPDNxQ3RMrirkH6H", Data: []byte("../checksum/GPa4aBakdSJd7Tz7LYj_VJFoojzyZinmVcG3k6M5xI6CZ821J5sXLhLDDuS47gi9")},
-			{Mode: fs.ModeSymlink | 0777, Path: "identifier/nfeISfLeFDr1k-g3hpE1oZ440kTqDdfF8TDpoLdbTPqaMMIl95oiqcvqjRkMjubA", Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			{Mode: fs.ModeSymlink | 0777, Path: "identifier/cGvuAdKA2tThRa4w3ZI2c5S5TXDx4j2qvfFM7pzf7y5vBz7NisBV06ThBXw_97xK", Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
 
 			{Mode: fs.ModeDir | 0700, Path: "temp"},
 			{Mode: fs.ModeDir | 0700, Path: "work"},
-		}, pkg.MustDecode("VIqqpf0ip9jcyw63i6E8lCMGUcLivQBe4Bevt3WusNac-1MSy5bzB647qGUBzl-W"), nil},
+		}, pkg.MustDecode("PAZyVTxxROg4eCQX3yKuiIlB1k9VFXmtvvyy7QxoqaFhYwGZpT4wYec4R2dTtfyh"), nil},
 
 		{"sample exec container overlay work", fstest.MapFS{
 			".": {Mode: fs.ModeDir | 0700},
@@ -402,8 +402,8 @@ func TestFlatten(t *testing.T) {
 			"checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU":       {Mode: fs.ModeDir | 0500},
 
 			"identifier": {Mode: fs.ModeDir | 0700},
-			"identifier/acaDzHZv40dZaz4cGAXayqbRMgbEOuiuiUijZL8IgDQvyeCNMFE3onBMYfny-kXA": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/GPa4aBakdSJd7Tz7LYj_VJFoojzyZinmVcG3k6M5xI6CZ821J5sXLhLDDuS47gi9")},
+			"identifier/Fud5ldJfpsgLt-rkLWrLO-aVYhQm-esTswetjxydPeQMK4jHNJ_1fGHVahaiCZ9y": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/GPa4aBakdSJd7Tz7LYj_VJFoojzyZinmVcG3k6M5xI6CZ821J5sXLhLDDuS47gi9")},
-			"identifier/nfeISfLeFDr1k-g3hpE1oZ440kTqDdfF8TDpoLdbTPqaMMIl95oiqcvqjRkMjubA": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			"identifier/cGvuAdKA2tThRa4w3ZI2c5S5TXDx4j2qvfFM7pzf7y5vBz7NisBV06ThBXw_97xK": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
 
 			"temp": {Mode: fs.ModeDir | 0700},
 			"work": {Mode: fs.ModeDir | 0700},
@@ -416,12 +416,12 @@ func TestFlatten(t *testing.T) {
 			{Mode: fs.ModeDir | 0500, Path: "checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU"},
 
 			{Mode: fs.ModeDir | 0700, Path: "identifier"},
-			{Mode: fs.ModeSymlink | 0777, Path: "identifier/acaDzHZv40dZaz4cGAXayqbRMgbEOuiuiUijZL8IgDQvyeCNMFE3onBMYfny-kXA", Data: []byte("../checksum/GPa4aBakdSJd7Tz7LYj_VJFoojzyZinmVcG3k6M5xI6CZ821J5sXLhLDDuS47gi9")},
+			{Mode: fs.ModeSymlink | 0777, Path: "identifier/Fud5ldJfpsgLt-rkLWrLO-aVYhQm-esTswetjxydPeQMK4jHNJ_1fGHVahaiCZ9y", Data: []byte("../checksum/GPa4aBakdSJd7Tz7LYj_VJFoojzyZinmVcG3k6M5xI6CZ821J5sXLhLDDuS47gi9")},
-			{Mode: fs.ModeSymlink | 0777, Path: "identifier/nfeISfLeFDr1k-g3hpE1oZ440kTqDdfF8TDpoLdbTPqaMMIl95oiqcvqjRkMjubA", Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			{Mode: fs.ModeSymlink | 0777, Path: "identifier/cGvuAdKA2tThRa4w3ZI2c5S5TXDx4j2qvfFM7pzf7y5vBz7NisBV06ThBXw_97xK", Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
 
 			{Mode: fs.ModeDir | 0700, Path: "temp"},
 			{Mode: fs.ModeDir | 0700, Path: "work"},
-		}, pkg.MustDecode("q8x2zQg4YZbKpPqKlEBj_uxXD9vOBaZ852qOuIsl9QdO73I_UMNpuUoPLtunxUYl"), nil},
+		}, pkg.MustDecode("uMZyWOQGjhI1oNKfJyw8I6EtUmWkOsZNeUEZLjy1lmkAV7cR1hmOKsOlXs4RkuEC"), nil},
 
 		{"sample exec container multiple layers", fstest.MapFS{
 			".": {Mode: fs.ModeDir | 0700},
@@ -435,10 +435,10 @@ func TestFlatten(t *testing.T) {
 			"checksum/nY_CUdiaUM1OL4cPr5TS92FCJ3rCRV7Hm5oVTzAvMXwC03_QnTRfQ5PPs7mOU9fK/check": {Mode: 0400, Data: []byte("layers")},
 
 			"identifier": {Mode: fs.ModeDir | 0700},
+			"identifier/YK1yDoi_qaUuXSPeVLJnaL8CBuZC4LoCarId5vdBCTLU82-vZFIfLDlaJuLM1iBj": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/nY_CUdiaUM1OL4cPr5TS92FCJ3rCRV7Hm5oVTzAvMXwC03_QnTRfQ5PPs7mOU9fK")},
 			"identifier/_gAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/OLBgp1GsljhM2TJ-sbHjaiH9txEUvgdDTAzHv2P24donTt6_529l-9Ua0vFImLlb")},
-			"identifier/nfeISfLeFDr1k-g3hpE1oZ440kTqDdfF8TDpoLdbTPqaMMIl95oiqcvqjRkMjubA": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			"identifier/cGvuAdKA2tThRa4w3ZI2c5S5TXDx4j2qvfFM7pzf7y5vBz7NisBV06ThBXw_97xK": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
-			"identifier/rXLKjjYfGSyoWmuvEJooHkvGJIZaC0IAWnKGvtPZkM15gBxAgW7mIXcxRVNOXAr4": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/nY_CUdiaUM1OL4cPr5TS92FCJ3rCRV7Hm5oVTzAvMXwC03_QnTRfQ5PPs7mOU9fK")},
+			"identifier/g6gj2JWNXN-oNikou626vDqcMeZCn_TcV4xKuizBaPAWcasG2sVvItb5kZovMrzE": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/GPa4aBakdSJd7Tz7LYj_VJFoojzyZinmVcG3k6M5xI6CZ821J5sXLhLDDuS47gi9")},
-			"identifier/tfjrsVuBuFgzWgwz-yPppFtylYuC1VFWnKhyBiHbWTGkyz8lt7Ee9QXWaIHPXs4x": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/GPa4aBakdSJd7Tz7LYj_VJFoojzyZinmVcG3k6M5xI6CZ821J5sXLhLDDuS47gi9")},
 
 			"temp": {Mode: fs.ModeDir | 0700},
 			"work": {Mode: fs.ModeDir | 0700},
@@ -454,14 +454,14 @@ func TestFlatten(t *testing.T) {
 			{Mode: 0400, Path: "checksum/nY_CUdiaUM1OL4cPr5TS92FCJ3rCRV7Hm5oVTzAvMXwC03_QnTRfQ5PPs7mOU9fK/check", Data: []byte("layers")},
 
 			{Mode: fs.ModeDir | 0700, Path: "identifier"},
+			{Mode: fs.ModeSymlink | 0777, Path: "identifier/YK1yDoi_qaUuXSPeVLJnaL8CBuZC4LoCarId5vdBCTLU82-vZFIfLDlaJuLM1iBj", Data: []byte("../checksum/nY_CUdiaUM1OL4cPr5TS92FCJ3rCRV7Hm5oVTzAvMXwC03_QnTRfQ5PPs7mOU9fK")},
 			{Mode: fs.ModeSymlink | 0777, Path: "identifier/_gAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA", Data: []byte("../checksum/OLBgp1GsljhM2TJ-sbHjaiH9txEUvgdDTAzHv2P24donTt6_529l-9Ua0vFImLlb")},
-			{Mode: fs.ModeSymlink | 0777, Path: "identifier/nfeISfLeFDr1k-g3hpE1oZ440kTqDdfF8TDpoLdbTPqaMMIl95oiqcvqjRkMjubA", Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			{Mode: fs.ModeSymlink | 0777, Path: "identifier/cGvuAdKA2tThRa4w3ZI2c5S5TXDx4j2qvfFM7pzf7y5vBz7NisBV06ThBXw_97xK", Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
-			{Mode: fs.ModeSymlink | 0777, Path: "identifier/rXLKjjYfGSyoWmuvEJooHkvGJIZaC0IAWnKGvtPZkM15gBxAgW7mIXcxRVNOXAr4", Data: []byte("../checksum/nY_CUdiaUM1OL4cPr5TS92FCJ3rCRV7Hm5oVTzAvMXwC03_QnTRfQ5PPs7mOU9fK")},
+			{Mode: fs.ModeSymlink | 0777, Path: "identifier/g6gj2JWNXN-oNikou626vDqcMeZCn_TcV4xKuizBaPAWcasG2sVvItb5kZovMrzE", Data: []byte("../checksum/GPa4aBakdSJd7Tz7LYj_VJFoojzyZinmVcG3k6M5xI6CZ821J5sXLhLDDuS47gi9")},
-			{Mode: fs.ModeSymlink | 0777, Path: "identifier/tfjrsVuBuFgzWgwz-yPppFtylYuC1VFWnKhyBiHbWTGkyz8lt7Ee9QXWaIHPXs4x", Data: []byte("../checksum/GPa4aBakdSJd7Tz7LYj_VJFoojzyZinmVcG3k6M5xI6CZ821J5sXLhLDDuS47gi9")},
 
 			{Mode: fs.ModeDir | 0700, Path: "temp"},
 			{Mode: fs.ModeDir | 0700, Path: "work"},
-		}, pkg.MustDecode("SITnQ6PTV12PAQQjIuLUxkvsXQiC9Gq_HJQlcb4BPL5YnRHnx8lsW7PRM9YMLBsx"), nil},
+		}, pkg.MustDecode("OG6C_fL-U4dZndkiKJvXf31qrM7DNpmCGxbWASwhWK_e8twIwC_ZvMvw142pVqz-"), nil},
 
 		{"sample exec container layer promotion", fstest.MapFS{
 			".": {Mode: fs.ModeDir | 0700},
@@ -472,9 +472,9 @@ func TestFlatten(t *testing.T) {
 			"checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU":       {Mode: fs.ModeDir | 0500},
 
 			"identifier": {Mode: fs.ModeDir | 0700},
-			"identifier/1tQZOGmVk_JkpyiG84AKW_BXmlK_MvHUbh5WtMuthGbHUq7i7nL1bvdF-LoJbqNh": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			"identifier/CuKcA4aAApOvWqI6-KzZEDyGLltRdBjOTyrTibam2fFVxtXmGL_RVuElOFTVlKfq": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
-			"identifier/O-6VjlIUxc4PYLf5v35uhIeL8kkYCbHYklqlmDjFPXe0m4j6GkUDg5qwTzBRESnf": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/GPa4aBakdSJd7Tz7LYj_VJFoojzyZinmVcG3k6M5xI6CZ821J5sXLhLDDuS47gi9")},
+			"identifier/cGvuAdKA2tThRa4w3ZI2c5S5TXDx4j2qvfFM7pzf7y5vBz7NisBV06ThBXw_97xK": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
-			"identifier/nfeISfLeFDr1k-g3hpE1oZ440kTqDdfF8TDpoLdbTPqaMMIl95oiqcvqjRkMjubA": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			"identifier/ywzI31S5McuYu7vzI2kqpSC_nsNzpWBXVCwPoLAYi9QVT0mODgzqoo9jYYaczPbf": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/GPa4aBakdSJd7Tz7LYj_VJFoojzyZinmVcG3k6M5xI6CZ821J5sXLhLDDuS47gi9")},
 
 			"temp": {Mode: fs.ModeDir | 0700},
 			"work": {Mode: fs.ModeDir | 0700},
@@ -487,13 +487,13 @@ func TestFlatten(t *testing.T) {
 			{Mode: fs.ModeDir | 0500, Path: "checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU"},
 
 			{Mode: fs.ModeDir | 0700, Path: "identifier"},
-			{Mode: fs.ModeSymlink | 0777, Path: "identifier/1tQZOGmVk_JkpyiG84AKW_BXmlK_MvHUbh5WtMuthGbHUq7i7nL1bvdF-LoJbqNh", Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			{Mode: fs.ModeSymlink | 0777, Path: "identifier/CuKcA4aAApOvWqI6-KzZEDyGLltRdBjOTyrTibam2fFVxtXmGL_RVuElOFTVlKfq", Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
-			{Mode: fs.ModeSymlink | 0777, Path: "identifier/O-6VjlIUxc4PYLf5v35uhIeL8kkYCbHYklqlmDjFPXe0m4j6GkUDg5qwTzBRESnf", Data: []byte("../checksum/GPa4aBakdSJd7Tz7LYj_VJFoojzyZinmVcG3k6M5xI6CZ821J5sXLhLDDuS47gi9")},
+			{Mode: fs.ModeSymlink | 0777, Path: "identifier/cGvuAdKA2tThRa4w3ZI2c5S5TXDx4j2qvfFM7pzf7y5vBz7NisBV06ThBXw_97xK", Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
-			{Mode: fs.ModeSymlink | 0777, Path: "identifier/nfeISfLeFDr1k-g3hpE1oZ440kTqDdfF8TDpoLdbTPqaMMIl95oiqcvqjRkMjubA", Data: []byte("../checksum/MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU")},
+			{Mode: fs.ModeSymlink | 0777, Path: "identifier/ywzI31S5McuYu7vzI2kqpSC_nsNzpWBXVCwPoLAYi9QVT0mODgzqoo9jYYaczPbf", Data: []byte("../checksum/GPa4aBakdSJd7Tz7LYj_VJFoojzyZinmVcG3k6M5xI6CZ821J5sXLhLDDuS47gi9")},
 
 			{Mode: fs.ModeDir | 0700, Path: "temp"},
 			{Mode: fs.ModeDir | 0700, Path: "work"},
-		}, pkg.MustDecode("fuC20BhMKr86TYzNPP2A-9P7mGLvdcOiG10exlhRvZm8ySI7csf0LhW3im_26l1N"), nil},
+		}, pkg.MustDecode("CKt376G_wCHRR26hBxLnoXyz5boEOX12AiHbQM2qz4bejKtfmys3Swqh60eKFn9y"), nil},
 
 		{"sample file short", fstest.MapFS{
 			".": {Mode: fs.ModeDir | 0700},
@@ -502,7 +502,7 @@ func TestFlatten(t *testing.T) {
 			"checksum/vsAhtPNo4waRNOASwrQwcIPTqb3SBuJOXw2G4T1mNmVZM-wrQTRllmgXqcIIoRcX": {Mode: 0400, Data: []byte{0}},
 
 			"identifier": {Mode: fs.ModeDir | 0700},
-			"identifier/lIx_W4M7tVOcQ8jh08EJOfXf4brRmkEEjvUa7c17vVUzlmtUxlhhrgqmc9aZhjbn": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/vsAhtPNo4waRNOASwrQwcIPTqb3SBuJOXw2G4T1mNmVZM-wrQTRllmgXqcIIoRcX")},
+			"identifier/3nNZXzfgfDW2aHqmgf1VpJUYxe1GMzU7eA9Q_NnNVTDPpPOCTYKEVX-yscOiLT-e": {Mode: fs.ModeSymlink | 0777, Data: []byte("../checksum/vsAhtPNo4waRNOASwrQwcIPTqb3SBuJOXw2G4T1mNmVZM-wrQTRllmgXqcIIoRcX")},
 
 			"work": {Mode: fs.ModeDir | 0700},
 		}, []pkg.FlatEntry{
@@ -511,10 +511,10 @@ func TestFlatten(t *testing.T) {
 			{Mode: 0400, Path: "checksum/vsAhtPNo4waRNOASwrQwcIPTqb3SBuJOXw2G4T1mNmVZM-wrQTRllmgXqcIIoRcX", Data: []byte{0}},
 
 			{Mode: fs.ModeDir | 0700, Path: "identifier"},
-			{Mode: fs.ModeSymlink | 0777, Path: "identifier/lIx_W4M7tVOcQ8jh08EJOfXf4brRmkEEjvUa7c17vVUzlmtUxlhhrgqmc9aZhjbn", Data: []byte("../checksum/vsAhtPNo4waRNOASwrQwcIPTqb3SBuJOXw2G4T1mNmVZM-wrQTRllmgXqcIIoRcX")},
+			{Mode: fs.ModeSymlink | 0777, Path: "identifier/3nNZXzfgfDW2aHqmgf1VpJUYxe1GMzU7eA9Q_NnNVTDPpPOCTYKEVX-yscOiLT-e", Data: []byte("../checksum/vsAhtPNo4waRNOASwrQwcIPTqb3SBuJOXw2G4T1mNmVZM-wrQTRllmgXqcIIoRcX")},
 
 			{Mode: fs.ModeDir | 0700, Path: "work"},
-		}, pkg.MustDecode("hnrfmJtivNKcgtETsKnU9gP_OwPgpNY3DSUJnmxnmeOODSO-YBvEBiTgieY4AAd7"), nil},
+		}, pkg.MustDecode("azjTvqkTjLhFzvPDM4DEHiHyLupOnRq9GCikVN6DEElR1Gxz_BDo4SA0zZzaYUGa"), nil},
 	}
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {

internal/pkg/exec_test.go

@@ -78,7 +78,7 @@ func TestExec(t *testing.T) {
 				), nil, pkg.Checksum{}, &pkg.DependencyCureError{
 					{
 						Ident: unique.Make(pkg.ID(pkg.MustDecode(
-							"CWEoJqnSBpWf8uryC2qnIe3O1a_FZWUWZGbiVPsQFGW7pvDHiSwoK3QCU9-uxN87",
+							"zegItlAz7Lr1xFyzCtHTz_eL08KNuccT3S8b7zqekz3lZxqdELdqTlGjvUYPVykW",
 						))),
 						Err: stub.UniqueError(0xcafe),
 					},
@@ -109,7 +109,7 @@ func TestExec(t *testing.T) {
 			}
 
 			testtoolDestroy(t, base, c)
-		}, pkg.MustDecode("UiV6kMz7KrTsc_yphiyQzFLqjRanHxUOwrBMtkKuWo4mOO6WgPFAcoUEeSp7eVIW")},
+		}, pkg.MustDecode("BQb5SCAo0Rw0YBGqjGemK1jH3jk0cgxAQ-JyeqVRqaqmEevJ3jtXNL8HB470XNnB")},
 
 		{"net", nil, func(t *testing.T, base *check.Absolute, c *pkg.Cache) {
 			c.SetStrict(true)
@@ -144,7 +144,7 @@ func TestExec(t *testing.T) {
 			})
 
 			testtoolDestroy(t, base, c)
-		}, pkg.MustDecode("ek4K-0d4iRSArkY2TCs3WK34DbiYeOmhE_4vsJTSu_6roY4ZF3YG6eKRooal-i1o")},
+		}, pkg.MustDecode("hJ7nCMLea_09Z7Fi4ALXOgubMNwK7C61THdQobpQJhH3tnr7PJ86aY98Mte3rBje")},
 
 		{"overlay root", nil, func(t *testing.T, base *check.Absolute, c *pkg.Cache) {
 			c.SetStrict(true)
@@ -170,7 +170,7 @@ func TestExec(t *testing.T) {
 			})
 
 			testtoolDestroy(t, base, c)
-		}, pkg.MustDecode("VIqqpf0ip9jcyw63i6E8lCMGUcLivQBe4Bevt3WusNac-1MSy5bzB647qGUBzl-W")},
+		}, pkg.MustDecode("PAZyVTxxROg4eCQX3yKuiIlB1k9VFXmtvvyy7QxoqaFhYwGZpT4wYec4R2dTtfyh")},
 
 		{"overlay work", nil, func(t *testing.T, base *check.Absolute, c *pkg.Cache) {
 			c.SetStrict(true)
@@ -201,7 +201,7 @@ func TestExec(t *testing.T) {
 			})
 
 			testtoolDestroy(t, base, c)
-		}, pkg.MustDecode("q8x2zQg4YZbKpPqKlEBj_uxXD9vOBaZ852qOuIsl9QdO73I_UMNpuUoPLtunxUYl")},
+		}, pkg.MustDecode("uMZyWOQGjhI1oNKfJyw8I6EtUmWkOsZNeUEZLjy1lmkAV7cR1hmOKsOlXs4RkuEC")},
 
 		{"multiple layers", nil, func(t *testing.T, base *check.Absolute, c *pkg.Cache) {
 			c.SetStrict(true)
@@ -254,7 +254,7 @@ func TestExec(t *testing.T) {
 			})
 
 			testtoolDestroy(t, base, c)
-		}, pkg.MustDecode("SITnQ6PTV12PAQQjIuLUxkvsXQiC9Gq_HJQlcb4BPL5YnRHnx8lsW7PRM9YMLBsx")},
+		}, pkg.MustDecode("OG6C_fL-U4dZndkiKJvXf31qrM7DNpmCGxbWASwhWK_e8twIwC_ZvMvw142pVqz-")},
 
 		{"overlay layer promotion", nil, func(t *testing.T, base *check.Absolute, c *pkg.Cache) {
 			c.SetStrict(true)
@@ -286,7 +286,7 @@ func TestExec(t *testing.T) {
 			})
 
 			testtoolDestroy(t, base, c)
-		}, pkg.MustDecode("fuC20BhMKr86TYzNPP2A-9P7mGLvdcOiG10exlhRvZm8ySI7csf0LhW3im_26l1N")},
+		}, pkg.MustDecode("CKt376G_wCHRR26hBxLnoXyz5boEOX12AiHbQM2qz4bejKtfmys3Swqh60eKFn9y")},
 	})
 }
 

internal/pkg/file_test.go

@@ -17,13 +17,13 @@ func TestFile(t *testing.T) {
 			cureMany(t, c, []cureStep{
 				{"short", pkg.NewFile("null", []byte{0}), base.Append(
 					"identifier",
-					"lIx_W4M7tVOcQ8jh08EJOfXf4brRmkEEjvUa7c17vVUzlmtUxlhhrgqmc9aZhjbn",
+					"3nNZXzfgfDW2aHqmgf1VpJUYxe1GMzU7eA9Q_NnNVTDPpPOCTYKEVX-yscOiLT-e",
 				), pkg.MustDecode(
 					"vsAhtPNo4waRNOASwrQwcIPTqb3SBuJOXw2G4T1mNmVZM-wrQTRllmgXqcIIoRcX",
 				), nil},
 			})
 		}, pkg.MustDecode(
-			"hnrfmJtivNKcgtETsKnU9gP_OwPgpNY3DSUJnmxnmeOODSO-YBvEBiTgieY4AAd7",
+			"azjTvqkTjLhFzvPDM4DEHiHyLupOnRq9GCikVN6DEElR1Gxz_BDo4SA0zZzaYUGa",
 		)},
 	})
 }

internal/pkg/net_test.go

@@ -109,7 +109,7 @@ func TestHTTPGet(t *testing.T) {
 			)
 			wantPathname := base.Append(
 				"identifier",
-				"NqVORkT6L9HX6Za7kT2zcibY10qFqBaxEjPiYFrBQX-ZFr3yxCzJxbKOP0zVjeWb",
+				"00BNNr-PsNMtowTpEG86ZeI7eQKoD-pjSCPAal1e5MYqr_N7FLpyXKdXLXE8WEBF",
 			)
 			if pathname, checksum, err := c.Cure(f); err != nil {
 				t.Fatalf("Cure: error = %v", err)
@@ -156,6 +156,6 @@ func TestHTTPGet(t *testing.T) {
 			if _, _, err := c.Cure(f); !reflect.DeepEqual(err, wantErrNotFound) {
 				t.Fatalf("Pathname: error = %#v, want %#v", err, wantErrNotFound)
 			}
-		}, pkg.MustDecode("bqtn69RkV5E7V7GhhgCFjcvbxmaqrO8DywamM4Tyjf10F6EJBHjXiIa_tFRtF4iN")},
+		}, pkg.MustDecode("KkdL8x2a84V8iYZop5jSTyba54xSgf_NZ1R0c4nSp9xTdk3SK_zUKGhNJ2uK8wMY")},
 	})
 }

internal/pkg/pkg.go

@@ -589,12 +589,21 @@ func (c *Cache) unsafeIdent(a Artifact, encodeKind bool) (
 	h := sha512.New384()
 	binary.LittleEndian.PutUint64(buf[:], uint64(a.Kind()))
 	h.Write(buf[:wordSize])
-	i := IContext{c, h}
-	a.Params(&i)
-	i.cache, i.h = nil, nil
 	for _, dn := range idents {
 		h.Write(dn[:])
 	}
+	kcBuf := c.getIdentBuf()
+	if kc, ok := a.(KnownChecksum); ok {
+		*(*Checksum)(kcBuf[:]) = kc.Checksum()
+	} else {
+		*(*Checksum)(kcBuf[:]) = Checksum{}
+	}
+	h.Write((*Checksum)(kcBuf[:])[:])
+	c.putIdentBuf(kcBuf)
+
+	i := IContext{c, h}
+	a.Params(&i)
+	i.cache, i.h = nil, nil
 
 	h.Sum(buf[wordSize:wordSize])
 	return

internal/pkg/pkg_test.go

@@ -218,7 +218,7 @@ func TestIdent(t *testing.T) {
 			},
 			nil,
 		}, unique.Make[pkg.ID](pkg.MustDecode(
-			"HnySzeLQvSBZuTUcvfmLEX_OmH4yJWWH788NxuLuv7kVn8_uPM6Ks4rqFWM2NZJY",
+			"v86qCz5fDqUsjA3KY_4LIrEh3aQnp04plNiWJ5_ap06McHSSBlROyKIFEwx3c0O7",
 		))},
 	}
 
@@ -531,7 +531,7 @@ func TestCache(t *testing.T) {
 					kind:   pkg.KindExec,
 					params: []byte("artifact overridden to be incomplete"),
 				}}, nil, pkg.Checksum{}, pkg.InvalidArtifactError(pkg.MustDecode(
-					"da4kLKa94g1wN2M0qcKflqgf2-Y2UL36iehhczqsIIW8G0LGvM7S8jjtnBc0ftB0",
+					"0z3fA0YngFaRRCQRrxKburhpAGz3gkYIZ346X_tAwOr_ldelYg1nTifI3-WX8hQD",
 				))},
 
 				{"error passthrough", newStubFile(

internal/pkg/tar_test.go

@@ -40,7 +40,7 @@ func TestTar(t *testing.T) {
 			}, pkg.MustDecode(
 				"cTw0h3AmYe7XudSoyEMByduYXqGi-N5ZkTZ0t9K5elsu3i_jNIVF5T08KR1roBFM",
 			))
-		}, pkg.MustDecode("sxbgyX-bPoezbha214n2lbQhiVfTUBkhZ0EX6zI7mmkMdrCdwuMwhMBJphLQsy94")},
+		}, pkg.MustDecode("nnOiyjjjvgZChsGtO4rA1JHckwYBBbxwNfecPJp62OFP6aoYUxHQ5UtYsrDpnwan")},
 
 		{"http expand", nil, func(t *testing.T, base *check.Absolute, c *pkg.Cache) {
 			checkTarHTTP(t, base, c, fstest.MapFS{
@@ -51,7 +51,7 @@ func TestTar(t *testing.T) {
 			}, pkg.MustDecode(
 				"CH3AiUrCCcVOjOYLaMKKK1Da78989JtfHeIsxMzWOQFiN4mrCLDYpoDxLWqJWCUN",
 			))
-		}, pkg.MustDecode("4I8wx_h7NSJTlG5lbuz-GGEXrOg0GYC3M_503LYEBhv5XGWXfNIdIY9Q3eVSYldX")},
+		}, pkg.MustDecode("bQVH19N7dX50SdQ6JNVYbFdDZV4t8IaM4dhxGvjACpdoEgJ2jZJfYKLH4ya7ZD_s")},
 	})
 }
 
@@ -99,13 +99,17 @@ func checkTarHTTP(
 	wantIdent := func() pkg.ID {
 		h := sha512.New384()
 		h.Write([]byte{byte(pkg.KindTar), 0, 0, 0, 0, 0, 0, 0})
-		h.Write([]byte{pkg.TarGzip, 0, 0, 0, 0, 0, 0, 0})
-		h.Write([]byte{byte(pkg.KindHTTPGet), 0, 0, 0, 0, 0, 0, 0})
 
+		h.Write([]byte{byte(pkg.KindHTTPGet), 0, 0, 0, 0, 0, 0, 0})
 		h0 := sha512.New384()
 		h0.Write([]byte{byte(pkg.KindHTTPGet), 0, 0, 0, 0, 0, 0, 0})
+		h0.Write(testdataChecksum[:])
 		h0.Write([]byte("file:///testdata"))
 		h.Write(h0.Sum(nil))
+
+		h.Write(make([]byte, len(pkg.Checksum{})))
+		h.Write([]byte{pkg.TarGzip, 0, 0, 0, 0, 0, 0, 0})
+
 		return pkg.ID(h.Sum(nil))
 	}()
 

internal/pkg/testdata/main.go

@@ -142,12 +142,12 @@ func main() {
 	}
 
 	const checksumEmptyDir = "MGWmEfjut2QE2xPJwTsmUzpff4BN_FEnQ7T0j7gvUCCiugJQNwqt9m151fm9D1yU"
-	ident := "U2cbgVgEtjfRuvHfE1cQnZ3t8yoexULQyo_VLgvxAVJSsobMcNaFIsuDWtmt7kzK"
+	ident := "LRxdkRYNKnZT6bKiu5W8ATeAAmq3n_5AAJkF6G0EpAOEloiZvADJBkfixgtgF1Z9"
 	log.Println(m)
 	next := func() { m = m.Next; log.Println(m) }
 
 	if overlayRoot {
-		ident = "5ey2wpmMpj483YYa7ZZQciYLA2cx3_l167JCqWW4Pd-5DVp81dj9EsBtVTwYptF6"
+		ident = "UB9HPeMgMPJf3Ut4jLWwnCtu_P3Lr29i8Erf084bHe8jjzBMKPDNxQ3RMrirkH6H"
 
 		if m.Root != "/" || m.Target != "/" ||
 			m.Source != "overlay" || m.FsType != "overlay" {
@@ -165,7 +165,7 @@ func main() {
 				log.Fatal("unexpected artifact checksum")
 			}
 		} else {
-			ident = "tfjrsVuBuFgzWgwz-yPppFtylYuC1VFWnKhyBiHbWTGkyz8lt7Ee9QXWaIHPXs4x"
+			ident = "g6gj2JWNXN-oNikou626vDqcMeZCn_TcV4xKuizBaPAWcasG2sVvItb5kZovMrzE"
 
 			lowerdirsEscaped := strings.Split(lowerdir, ":")
 			lowerdirs := lowerdirsEscaped[:0]
@@ -194,7 +194,7 @@ func main() {
 		}
 	} else {
 		if hostNet {
-			ident = "QdsJhGgnk5N2xdUNGcndXQxFKifxf1V_2t9X8CQ-pDcg24x6mGJC_BiLfGbs6Qml"
+			ident = "TAspufRsG2I_TsxUUj2b7bUnCHgcVSdh6aOZpzL0W5Bjn4EZmOGzjofaOWd8J11H"
 		}
 
 		if m.Root != "/sysroot" || m.Target != "/" {
@@ -213,14 +213,14 @@ func main() {
 	}
 
 	if promote {
-		ident = "O-6VjlIUxc4PYLf5v35uhIeL8kkYCbHYklqlmDjFPXe0m4j6GkUDg5qwTzBRESnf"
+		ident = "ywzI31S5McuYu7vzI2kqpSC_nsNzpWBXVCwPoLAYi9QVT0mODgzqoo9jYYaczPbf"
 	}
 
 	next() // testtool artifact
 
 	next()
 	if overlayWork {
-		ident = "acaDzHZv40dZaz4cGAXayqbRMgbEOuiuiUijZL8IgDQvyeCNMFE3onBMYfny-kXA"
+		ident = "Fud5ldJfpsgLt-rkLWrLO-aVYhQm-esTswetjxydPeQMK4jHNJ_1fGHVahaiCZ9y"
 		if m.Root != "/" || m.Target != "/work" ||
 			m.Source != "overlay" || m.FsType != "overlay" {
 			log.Fatal("unexpected work mount entry")