feat: add ipsw fw tc cmd

cmd/ipsw/cmd/fw/tc.go

@@ -22,7 +22,14 @@ THE SOFTWARE.
 package fw
 
 import (
+	"fmt"
+	"path/filepath"
+
 	"github.com/apex/log"
+	"github.com/blacktop/ipsw/internal/commands/extract"
+	fwcmd "github.com/blacktop/ipsw/internal/commands/fw"
+	"github.com/blacktop/ipsw/internal/magic"
+	"github.com/blacktop/ipsw/pkg/img4"
 	"github.com/spf13/cobra"
 	"github.com/spf13/viper"
 )
@@ -41,20 +48,58 @@ func init() {
 
 // tcCmd represents the tc command
 var tcCmd = &cobra.Command{
-	Use:    "tc",
-	Short:  "🚧 Dump TrustCache",
-	Args:   cobra.ExactArgs(1),
-	Hidden: true,
+	Use:   "tc <IM4P|IPSW>",
+	Short: "🚧 Dump TrustCache",
+	Args:  cobra.ExactArgs(1),
 	RunE: func(cmd *cobra.Command, args []string) error {
 
 		if viper.GetBool("verbose") {
 			log.SetLevel(log.DebugLevel)
 		}
 
-		// flags
-		// output := viper.GetString("fw.tc.output")
-
-		panic("not implemented")
+		if isZip, err := magic.IsZip(filepath.Clean(args[0])); err != nil {
+			return fmt.Errorf("failed to determine if file is a zip: %v", err)
+		} else if isZip {
+			out, err := extract.Search(&extract.Config{
+				IPSW:    filepath.Clean(args[0]),
+				Pattern: ".trustcache$",
+				Output:  viper.GetString("fw.tc.output"),
+			})
+			if err != nil {
+				return err
+			}
+			for _, f := range out {
+				if ok, _ := magic.IsIm4p(f); ok {
+					log.WithField("file", f).Info("Processing IM4P file")
+					im4p, err := img4.OpenIm4p(f)
+					if err != nil {
+						return err
+					}
+					tc, err := fwcmd.ParseTrustCache(im4p.Data)
+					if err != nil {
+						return fmt.Errorf("failed to parse trust cache: %v", err)
+					}
+					fmt.Println(tc)
+				} else {
+					return fmt.Errorf("unsupported file type: expected IM4P")
+				}
+			}
+		} else {
+			if ok, _ := magic.IsIm4p(filepath.Clean(args[0])); ok {
+				log.WithField("file", filepath.Clean(args[0])).Info("Processing IM4P file")
+				im4p, err := img4.OpenIm4p(filepath.Clean(args[0]))
+				if err != nil {
+					return err
+				}
+				tc, err := fwcmd.ParseTrustCache(im4p.Data)
+				if err != nil {
+					return fmt.Errorf("failed to parse trust cache: %v", err)
+				}
+				fmt.Println(tc)
+			} else {
+				return fmt.Errorf("unsupported file type: expected IM4P")
+			}
+		}
 
 		return nil
 	},

internal/commands/fw/trustcache.go

@@ -0,0 +1,189 @@
+package fw
+
+import (
+	"bytes"
+	"encoding/binary"
+	"encoding/hex"
+	"fmt"
+	"strings"
+
+	"github.com/blacktop/go-macho/types"
+)
+
+type hashType uint8
+
+const (
+	PAGE_SIZE_BITS = 12
+	PAGE_SIZE      = 1 << PAGE_SIZE_BITS
+
+	HASHTYPE_NOHASH           hashType = 0
+	HASHTYPE_SHA1             hashType = 1
+	HASHTYPE_SHA256           hashType = 2
+	HASHTYPE_SHA256_TRUNCATED hashType = 3
+	HASHTYPE_SHA384           hashType = 4
+	HASHTYPE_SHA512           hashType = 5
+
+	HASH_SIZE_SHA1             = 20
+	HASH_SIZE_SHA256           = 32
+	HASH_SIZE_SHA256_TRUNCATED = 20
+
+	CDHASH_LEN    = 20 /* always - larger hashes are truncated */
+	HASH_MAX_SIZE = 48 /* max size of the hash we'll support */
+)
+
+func (c hashType) String() string {
+	switch c {
+	case HASHTYPE_NOHASH:
+		return "no-hash"
+	case HASHTYPE_SHA1:
+		return "sha1"
+	case HASHTYPE_SHA256:
+		return "sha256"
+	case HASHTYPE_SHA256_TRUNCATED:
+		return "sha256 (Truncated)"
+	case HASHTYPE_SHA384:
+		return "sha384"
+	case HASHTYPE_SHA512:
+		return "sha512"
+	default:
+		return fmt.Sprintf("hashType(%d)", c)
+	}
+}
+
+type tcFlags uint8
+
+const (
+	CS_TRUST_CACHE_AMFID tcFlags = 1
+	CS_TRUST_CACHE_ANE   tcFlags = 2
+)
+
+func (c tcFlags) String() string {
+	var flags []string
+	if c&CS_TRUST_CACHE_AMFID != 0 {
+		flags = append(flags, "AMFID")
+	}
+	if c&CS_TRUST_CACHE_ANE != 0 {
+		flags = append(flags, "ANE")
+	}
+	if len(flags) == 0 {
+		return ""
+	}
+	return fmt.Sprintf(" flags=%s", strings.Join(flags, "|"))
+}
+
+type TrustCache struct {
+	TCHeader
+	Entries []any
+}
+
+type TCHeader struct {
+	Version    uint32
+	UUID       types.UUID
+	NumEntries uint32
+}
+
+type CDHash [CDHASH_LEN]byte
+
+func (c CDHash) String() string {
+	return hex.EncodeToString(c[:])
+}
+
+type TrustCacheEntryV1 struct {
+	CDHash   CDHash
+	HashType hashType
+	Flags    tcFlags
+}
+
+func (tc TrustCacheEntryV1) String() string {
+	return fmt.Sprintf("%s %s%s", tc.CDHash, tc.HashType, tc.Flags)
+}
+
+/*
+https://gist.github.com/LinusHenze/4cd5d7ef057a144cda7234e2c247c056
+
+Constraint Categories (from TrustCache, new in version 2):
+
+	Category 0:
+	    No Constraints
+
+	Category 1:
+	    Self Constraint: (on-authorized-authapfs-volume || on-system-volume) && launch-type == 1 && validation-category == 1
+	    Parent Constraint: is-init-proc
+
+	Category 2:
+	    Self Constraint: on-authorized-authapfs-volume || on-system-volume
+
+	Category 3:
+	    Self Constraint: (on-authorized-authapfs-volume || on-system-volume) && (launch-type == 0 || launch-type == 1) && validation-category == 1
+
+	Category 4:
+	    Self Constraint: (on-authorized-authapfs-volume || on-system-volume) && (launch-type == 0 || launch-type == 1) && validation-category == 1
+	    Parent Constraint: (on-system-volume && signing-identifier == "com.apple.mbfloagent" && validation-category == 1) || is-init-proc
+
+	Category 5:
+	    Self Constraint: validation-category == 1
+	    Parent Constraint: (on-system-volume && signing-identifier == "com.apple.mbfloagent" && validation-category == 1) || is-init-proc
+
+	Category 6:
+	    Self Constraint: (!in-tc-with-constraint-category || is-sip-protected || on-authorized-authapfs-volume || on-system-volume) && launch-type == 1 && validation-category == 1
+	    Parent Constraint: (apple-internal && entitlements["com.apple.private.set-launch-type.internal"] == 1) || is-init-proc
+
+	Category 7:
+	    Self Constraint: validation-category == 1
+*/
+type TrustCacheEntryV2 struct {
+	CDHash             CDHash
+	HashType           hashType
+	Flags              tcFlags
+	ConstraintCategory uint16
+}
+
+func (tc TrustCacheEntryV2) String() string {
+	var cat string
+	if tc.ConstraintCategory != 0 {
+		cat = fmt.Sprintf(" category=%d", tc.ConstraintCategory)
+	}
+	return fmt.Sprintf("%s %s%s%s", tc.CDHash, tc.HashType, cat, tc.Flags)
+}
+
+func (tc TrustCache) String() string {
+	var out string
+	out += fmt.Sprintf("UUID:       %s\n", tc.UUID)
+	out += fmt.Sprintf("Version:    %d\n", tc.Version)
+	out += fmt.Sprintf("NumEntries: %d\n", tc.NumEntries)
+	for _, entry := range tc.Entries {
+		out += fmt.Sprintf("    %s\n", entry)
+	}
+	return out
+}
+
+func ParseTrustCache(data []byte) (*TrustCache, error) {
+	var tc TrustCache
+
+	r := bytes.NewReader(data)
+
+	if err := binary.Read(r, binary.LittleEndian, &tc.TCHeader); err != nil {
+		return nil, err
+	}
+
+	for i := 0; i < int(tc.NumEntries); i++ {
+		switch tc.Version {
+		case 1:
+			var entry TrustCacheEntryV1
+			if err := binary.Read(r, binary.LittleEndian, &entry); err != nil {
+				return nil, err
+			}
+			tc.Entries = append(tc.Entries, entry)
+		case 2:
+			var entry TrustCacheEntryV2
+			if err := binary.Read(r, binary.LittleEndian, &entry); err != nil {
+				return nil, err
+			}
+			tc.Entries = append(tc.Entries, entry)
+		default:
+			return nil, fmt.Errorf("unsupported trust cache version: %d", tc.Version)
+		}
+	}
+
+	return &tc, nil
+}

www/docs/cli/ipsw/fw/fw.md

@@ -34,4 +34,5 @@ ipsw fw [flags]
 * [ipsw](/docs/cli/ipsw)	 - Download and Parse IPSWs (and SO much more)
 * [ipsw fw aea](/docs/cli/ipsw/fw/aea)	 - Parse AEA1 DMGs
 * [ipsw fw iboot](/docs/cli/ipsw/fw/iboot)	 - Dump firmwares
+* [ipsw fw tc](/docs/cli/ipsw/fw/tc)	 - 🚧 Dump TrustCache
 

www/docs/cli/ipsw/fw/tc.md

@@ -0,0 +1,36 @@
+---
+id: tc
+title: tc
+hide_title: true
+hide_table_of_contents: true
+sidebar_label: tc
+description: 🚧 Dump TrustCache
+---
+## ipsw fw tc
+
+🚧 Dump TrustCache
+
+```
+ipsw fw tc <IM4P|IPSW> [flags]
+```
+
+### Options
+
+```
+  -h, --help            help for tc
+  -o, --output string   Folder to extract files to
+```
+
+### Options inherited from parent commands
+
+```
+      --color           colorize output
+      --config string   config file (default is $HOME/.config/ipsw/config.yaml)
+      --no-color        disable colorize output
+  -V, --verbose         verbose output
+```
+
+### SEE ALSO
+
+* [ipsw fw](/docs/cli/ipsw/fw)	 - Firmware commands
+