Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 11373418 authored by Kenny Root's avatar Kenny Root
Browse files

Throw exception on odd length Signatures 

The old version of this code would silently truncate odd-length
Signatures. However, this masks some bugs. Add a throw of
IllegalArgumentException so users can easily see where they're getting
bad input for Signatures.

Also, go through the existing code and catch this exception or
pre-check the input strings so system_server doesn't crash later.

Bug: 5092338
Change-Id: I8c672c5eaeb738a92c4581ce0df09baf719980ef
parent 62c7b375

core/java/android/content/pm/Signature.java

+27 −14
Original line number Diff line number Diff line
@@ -16,7 +16,6 @@ 


package android.content.pm;



import android.content.ComponentName;

import android.os.Parcel;

import android.os.Parcelable;
@@ -40,26 +39,41 @@ public class Signature implements Parcelable { 
        mSignature = signature.clone();

    }



    private static final int parseHexDigit(int nibble) {

        if ('0' <= nibble && nibble <= '9') {

            return nibble - '0';

        } else if ('a' <= nibble && nibble <= 'f') {

            return nibble - 'a' + 10;

        } else if ('A' <= nibble && nibble <= 'F') {

            return nibble - 'A' + 10;

        } else {

            throw new IllegalArgumentException("Invalid character " + nibble + " in hex string");

        }

    }



    /**

     * Create Signature from a text representation previously returned by

     * {@link #toChars} or {@link #toCharsString()}.

     * {@link #toChars} or {@link #toCharsString()}. Signatures are expected to

     * be a hex-encoded ASCII string.

     *

     * @param text hex-encoded string representing the signature

     * @throws IllegalArgumentException when signature is odd-length

     */

    public Signature(String text) {

        final byte[] input = text.getBytes();

        final int N = input.length;



        if (N % 2 != 0) {

            throw new IllegalArgumentException("text size " + N + " is not even");

        }



        final byte[] sig = new byte[N / 2];

        int sigIndex = 0;



        for (int i = 0; i < N;) {

            int b;



            final int hi = input[i++];

            b = (hi >= 'a' ? (hi - 'a' + 10) : (hi - '0')) << 4;



            final int lo = input[i++];

            b |= (lo >= 'a' ? (lo - 'a' + 10) : (lo - '0')) & 0x0F;



            sig[sigIndex++] = (byte) (b & 0xFF);

            final int hi = parseHexDigit(input[i++]);

            final int lo = parseHexDigit(input[i++]);

            sig[sigIndex++] = (byte) ((hi << 4) | lo);

        }



        mSignature = sig;
@@ -100,8 +114,7 @@ public class Signature implements Parcelable { 
    }



    /**

     * Return the result of {@link #toChars()} as a String.  This result is

     * cached so future calls will return the same String.

     * Return the result of {@link #toChars()} as a String.

     */

    public String toCharsString() {

        String str = mStringRef == null ? null : mStringRef.get();
@@ -127,7 +140,7 @@ public class Signature implements Parcelable { 
        try {

            if (obj != null) {

                Signature other = (Signature)obj;

                return Arrays.equals(mSignature, other.mSignature);

                return this == other || Arrays.equals(mSignature, other.mSignature);

            }

        } catch (ClassCastException e) {

        }

services/java/com/android/server/BackupManagerService.java

+2 −0
Original line number Diff line number Diff line
@@ -3298,6 +3298,8 @@ class BackupManagerService extends IBackupManager.Stub { 
                }

            } catch (NumberFormatException e) {

                Slog.w(TAG, "Corrupt restore manifest for package " + info.packageName);

            } catch (IllegalArgumentException e) {

                Slog.w(TAG, e.getMessage());

            }



            return policy;

services/java/com/android/server/pm/PackageSignatures.java

+6 −0
Original line number Diff line number Diff line
@@ -138,6 +138,12 @@ class PackageSignatures { 
                                    "Error in package manager settings: <cert> "

                                       + "index " + index + " is not a number at "

                                       + parser.getPositionDescription());

                        } catch (IllegalArgumentException e) {

                            PackageManagerService.reportSettingsProblem(Log.WARN,

                                    "Error in package manager settings: <cert> "

                                       + "index " + index + " has an invalid signature at "

                                       + parser.getPositionDescription() + ": "

                                       + e.getMessage());

                        }

                    } else {

                        PackageManagerService.reportSettingsProblem(Log.WARN,