Add zipadjust JNI code

.gitignore

@@ -5,3 +5,4 @@
 /build
 app/app-release.apk
 *.hprof
+app/.externalNativeBuild/

app/CMakeLists.txt

@@ -0,0 +1,5 @@
+cmake_minimum_required(VERSION 3.6)
+add_library(zipadjust SHARED src/main/jni/zipadjust.c)
+find_library(libz z)
+find_library(liblog log)
+target_link_libraries(zipadjust ${libz} ${liblog})

app/build.gradle

@@ -13,6 +13,11 @@ android {
         jackOptions {
             enabled true
         }
+        ndk {
+            moduleName 'zipadjust'
+//            abiFilters 'x86', 'x86_64', 'armeabi', 'armeabi-v7a', 'arm64-v8a'
+            abiFilters 'x86', 'x86_64', 'armeabi'
+        }
     }
 
     buildTypes {
@@ -27,6 +32,11 @@ android {
     dexOptions {
         preDexLibraries = false
     }
+    externalNativeBuild {
+        cmake {
+            path 'CMakeLists.txt'
+        }
+    }
 }
 repositories {
     jcenter()

app/src/main/java/com/topjohnwu/magisk/adapters/ReposAdapter.java

@@ -30,7 +30,6 @@ import com.topjohnwu.magisk.utils.ZipUtils;
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
-import java.io.InputStream;
 import java.io.OutputStream;
 import java.util.List;
 
@@ -113,16 +112,15 @@ public class ReposAdapter extends RecyclerView.Adapter<ReposAdapter.ViewHolder>
 
                                             // First remove top folder (the folder with the repo name) in Github source zip
                                             ZipUtils.removeTopFolder(mContext.getContentResolver().openInputStream(uri), outBuffer);
-                                            inBuffer = new ByteArrayInputStream(outBuffer.toByteArray().clone());
+                                            inBuffer = new ByteArrayInputStream(outBuffer.toByteArray());
                                             outBuffer.reset();
 
                                             // Then sign the zip for the first time
                                             ZipUtils.signZip(mContext, inBuffer, outBuffer, false);
-                                            inBuffer = new ByteArrayInputStream(outBuffer.toByteArray().clone());
-                                            outBuffer.reset();
 
-                                            // ZipAdjust to be placed here
-                                            // Call JNI for zipadjust...
+                                            // Call zipadjust through JNI
+                                            inBuffer = new ByteArrayInputStream(ZipUtils.zipAdjust(outBuffer.toByteArray(), outBuffer.size()));
+                                            outBuffer.reset();
 
                                             // Finally, sign the whole zip file again
                                             ZipUtils.signZip(mContext, inBuffer, outBuffer, true);

app/src/main/java/com/topjohnwu/magisk/utils/ZipUtils.java

@@ -23,7 +23,6 @@ import org.spongycastle.util.encoders.Base64;
 
 import java.io.ByteArrayOutputStream;
 import java.io.File;
-import java.io.FileInputStream;
 import java.io.FilterOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
@@ -74,6 +73,14 @@ public class ZipUtils {
     private static final int USE_SHA1 = 1;
     private static final int USE_SHA256 = 2;
 
+    static {
+        System.loadLibrary("zipadjust");
+        sBouncyCastleProvider = new BouncyCastleProvider();
+        Security.insertProviderAt(sBouncyCastleProvider, 1);
+    }
+
+    public native static byte[] zipAdjust(byte[] bytes, int size);
+
     public static void removeTopFolder(InputStream in, OutputStream out) {
         try {
             JarInputStream source = new JarInputStream(in);
@@ -106,8 +113,6 @@ public class ZipUtils {
 
     public static void signZip(Context context, InputStream inputStream,
                                OutputStream outputStream, boolean signWholeFile) {
-        sBouncyCastleProvider = new BouncyCastleProvider();
-        Security.insertProviderAt(sBouncyCastleProvider, 1);
         JarMap inputJar;
         int hashes = 0;
         try {

app/src/main/jni/zipadjust.c

@@ -0,0 +1,307 @@
+#include <jni.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <zlib.h>
+#include <android/log.h>
+
+#define  LOG_TAG    "zipadjust"
+
+#define  LOGD(...)  __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG, __VA_ARGS__)
+#define  LOGE(...)  __android_log_print(ANDROID_LOG_ERROR, LOG_TAG, __VA_ARGS__)
+
+size_t insize, outsize = 0, alloc = 0;
+unsigned char *fin, *fout;
+
+int zipadjust(int decompress) ;
+
+JNIEXPORT jbyteArray JNICALL
+Java_com_topjohnwu_magisk_utils_ZipUtils_zipAdjust(JNIEnv *env, jclass type, jbyteArray jbytes,
+                                                   jint size) {
+    fin = (*env)->GetPrimitiveArrayCritical(env, jbytes, NULL);
+    insize = (size_t) size;
+
+    zipadjust(0);
+
+    (*env)->ReleasePrimitiveArrayCritical(env, jbytes, fin, 0);
+
+    jbyteArray ret = (*env)->NewByteArray(env, outsize);
+    (*env)->SetByteArrayRegion(env, ret, 0, outsize, (const jbyte*) fout);
+    free(fout);
+
+    return ret;
+}
+
+#pragma pack(1)
+struct local_header_struct {
+    uint32_t signature;
+    uint16_t extract_version;
+    uint16_t flags;
+    uint16_t compression_method;
+    uint16_t last_modified_time;
+    uint16_t last_modified_date;
+    uint32_t crc32;
+    uint32_t size_compressed;
+    uint32_t size_uncompressed;
+    uint16_t length_filename;
+    uint16_t length_extra;
+    // filename
+    // extra
+};
+typedef struct local_header_struct local_header_t;
+
+#pragma pack(1)
+struct data_descriptor_struct {
+    uint32_t signature;
+    uint32_t crc32;
+    uint32_t size_compressed;
+    uint32_t size_uncompressed;
+};
+typedef struct data_descriptor_struct data_descriptor_t;
+
+#pragma pack(1)
+struct central_header_struct {
+    uint32_t signature;
+    uint16_t version_made;
+    uint16_t version_needed;
+    uint16_t flags;
+    uint16_t compression_method;
+    uint16_t last_modified_time;
+    uint16_t last_modified_date;
+    uint32_t crc32;
+    uint32_t size_compressed;
+    uint32_t size_uncompressed;
+    uint16_t length_filename;
+    uint16_t length_extra;
+    uint16_t length_comment;
+    uint16_t disk_start;
+    uint16_t attr_internal;
+    uint32_t attr_external;
+    uint32_t offset;
+    // filename
+    // extra
+    // comment
+};
+typedef struct central_header_struct central_header_t;
+
+#pragma pack(1)
+struct central_footer_struct {
+    uint32_t signature;
+    uint16_t disk_number;
+    uint16_t disk_number_central_directory;
+    uint16_t central_directory_entries_this_disk;
+    uint16_t central_directory_entries_total;
+    uint32_t central_directory_size;
+    uint32_t central_directory_offset;
+    uint16_t length_comment;
+    // comment
+};
+typedef struct central_footer_struct central_footer_t;
+
+#define MAGIC_LOCAL_HEADER 0x04034b50
+#define MAGIC_DATA_DESCRIPTOR 0x08074b50
+#define MAGIC_CENTRAL_HEADER 0x02014b50
+#define MAGIC_CENTRAL_FOOTER 0x06054b50
+
+static int xerror(char* message) {
+    LOGE("%s\n", message);
+    return 0;
+}
+
+static int xseekread(off_t offset, void* buf, size_t bytes) {
+    memcpy(buf, fin + offset, bytes);
+    return 1;
+}
+
+static int xseekwrite(off_t offset, const void* buf, size_t bytes) {
+    if (offset + bytes > outsize) outsize = offset + bytes;
+    if (outsize > alloc) {
+        fout = realloc(fout, outsize);
+        alloc = outsize;
+    }
+    memcpy(fout + offset, buf, bytes);
+    return 1;
+}
+
+static int xfilecopy(off_t offsetIn, off_t offsetOut, size_t bytes) {
+    unsigned int CHUNK = 256 * 1024;
+    unsigned char* buf = malloc(CHUNK);
+    if (buf == NULL) return xerror("malloc failed");
+    size_t left = bytes;
+    while (left > 0) {
+        size_t wanted = (left < CHUNK) ? left : CHUNK;
+        xseekread(offsetIn, buf, wanted);
+        xseekwrite(offsetOut, buf, wanted);
+        offsetIn += wanted;
+        offsetOut += wanted;
+        left -= wanted;
+    }
+    free(buf);
+
+    return 1;
+}
+
+static int xdecompress(off_t offsetIn, off_t offsetOut, size_t bytes) {
+    unsigned int CHUNK = 256 * 1024;
+
+    int ret;
+    unsigned have;
+    z_stream strm;
+    unsigned char in[CHUNK];
+    unsigned char out[CHUNK];
+
+    strm.zalloc = Z_NULL;
+    strm.zfree = Z_NULL;
+    strm.opaque = Z_NULL;
+    strm.avail_in = 0;
+    strm.next_in = Z_NULL;
+    ret = inflateInit2(&strm, -15);
+    if (ret != Z_OK) return xerror("ret != Z_OK");
+
+    do {
+        strm.avail_in = insize - offsetIn;
+        if (strm.avail_in == 0) break;
+        strm.avail_in = (strm.avail_in > CHUNK) ? CHUNK : strm.avail_in;
+        xseekread(offsetIn, in, strm.avail_in);
+        strm.next_in = in;
+        offsetIn += strm.avail_in;
+
+        do {
+            strm.avail_out = CHUNK;
+            strm.next_out = out;
+
+            ret = inflate(&strm, Z_NO_FLUSH);
+            if (ret == Z_STREAM_ERROR) return xerror("Stream error");
+            switch (ret) {
+                case Z_NEED_DICT:
+                    ret = Z_DATA_ERROR;
+                case Z_DATA_ERROR:
+                case Z_MEM_ERROR:
+                    (void)inflateEnd(&strm);
+                    return xerror("DICT/DATA/MEM error");
+            }
+
+            have = CHUNK - strm.avail_out;
+            xseekwrite(offsetOut, out, have);
+            offsetOut += have;
+        } while (strm.avail_out == 0);
+    } while (ret != Z_STREAM_END);
+    (void)inflateEnd(&strm);
+
+    return ret == Z_STREAM_END ? 1 : 0;
+}
+
+int zipadjust(int decompress) {
+    int ok = 0;
+
+    char filename[1024];
+
+    central_footer_t central_footer;
+    uint32_t central_directory_in_position = 0;
+    uint32_t central_directory_in_size = 0;
+    uint32_t central_directory_out_size = 0;
+
+    int i;
+    for (i = insize - 4; i >= 0; i--) {
+        uint32_t magic = 0;
+        if (!xseekread(i, &magic, sizeof(uint32_t))) return 0;
+        if (magic == MAGIC_CENTRAL_FOOTER) {
+            LOGD("central footer @ %08X\n", i);
+            if (!xseekread(i, &central_footer, sizeof(central_footer_t))) return 0;
+
+            central_header_t central_header;
+            if (!xseekread(central_footer.central_directory_offset, &central_header, sizeof(central_header_t))) return 0;
+            if ( central_header.signature == MAGIC_CENTRAL_HEADER ) {
+                central_directory_in_position = central_footer.central_directory_offset;
+                central_directory_in_size = insize - central_footer.central_directory_offset;
+                LOGD("central header @ %08X (%d)\n", central_footer.central_directory_offset, central_footer.central_directory_size);
+                break;
+            }
+        }
+    }
+
+    if (central_directory_in_position == 0) return 0;
+
+    unsigned char* central_directory_in = (unsigned char*)malloc(central_directory_in_size);
+    unsigned char* central_directory_out = (unsigned char*)malloc(central_directory_in_size);
+    if (!xseekread(central_directory_in_position, central_directory_in, central_directory_in_size)) return 0;
+    memset(central_directory_out, 0, central_directory_in_size);
+
+
+
+    fout = (unsigned char*) malloc(insize);
+    alloc = insize;
+
+    uintptr_t central_directory_in_index = 0;
+    uintptr_t central_directory_out_index = 0;
+
+    central_header_t* central_header = NULL;
+
+    uint32_t out_index = 0;
+
+    while (1) {
+        central_header = (central_header_t*)&central_directory_in[central_directory_in_index];
+        if (central_header->signature != MAGIC_CENTRAL_HEADER) break;
+
+        filename[central_header->length_filename] = (char)0;
+        memcpy(filename, &central_directory_in[central_directory_in_index + sizeof(central_header_t)], central_header->length_filename);
+        LOGD("%s (%d --> %d) [%08X] (%d)\n", filename, central_header->size_uncompressed, central_header->size_compressed, central_header->crc32, central_header->length_extra + central_header->length_comment);
+
+        local_header_t local_header;
+        if (!xseekread(central_header->offset, &local_header, sizeof(local_header_t))) return 0;
+
+        // save and update to next index before we clobber the data
+        uint16_t compression_method_old = central_header->compression_method;
+        uint32_t size_compressed_old = central_header->size_compressed;
+        uint32_t offset_old = central_header->offset;
+        uint32_t length_extra_old = central_header->length_extra;
+        central_directory_in_index += sizeof(central_header_t) + central_header->length_filename + central_header->length_extra + central_header->length_comment;
+
+        // copying, rewriting, and correcting local and central headers so all the information matches, and no data descriptors are necessary
+        central_header->offset = out_index;
+        central_header->flags = central_header->flags & !8;
+        if (decompress && (compression_method_old == 8)) {
+            central_header->compression_method = 0;
+            central_header->size_compressed = central_header->size_uncompressed;
+        }
+        central_header->length_extra = 0;
+        central_header->length_comment = 0;
+        local_header.compression_method = central_header->compression_method;
+        local_header.flags = central_header->flags;
+        local_header.crc32 = central_header->crc32;
+        local_header.size_uncompressed = central_header->size_uncompressed;
+        local_header.size_compressed = central_header->size_compressed;
+        local_header.length_extra = 0;
+
+        if (!xseekwrite(out_index, &local_header, sizeof(local_header_t))) return 0;
+        out_index += sizeof(local_header_t);
+        if (!xseekwrite(out_index, &filename[0], central_header->length_filename)) return 0;
+        out_index += central_header->length_filename;
+
+        if (decompress && (compression_method_old == 8)) {
+            if (!xdecompress(offset_old + sizeof(local_header_t) + central_header->length_filename + length_extra_old, out_index, size_compressed_old)) return 0;
+        } else {
+            if (!xfilecopy(offset_old + sizeof(local_header_t) + central_header->length_filename + length_extra_old, out_index, size_compressed_old)) return 0;
+        }
+        out_index += local_header.size_compressed;
+
+        memcpy(&central_directory_out[central_directory_out_index], central_header, sizeof(central_header_t) + central_header->length_filename);
+        central_directory_out_index += sizeof(central_header_t) + central_header->length_filename;
+    }
+
+    central_directory_out_size = central_directory_out_index;
+    central_footer.central_directory_size = central_directory_out_size;
+    central_footer.central_directory_offset = out_index;
+    central_footer.length_comment = 0;
+    if (!xseekwrite(out_index, central_directory_out, central_directory_out_size)) return 0;
+    out_index += central_directory_out_size;
+    if (!xseekwrite(out_index, &central_footer, sizeof(central_footer_t))) return 0;
+
+    LOGD("central header @ %08X (%d)\n", central_footer.central_directory_offset, central_footer.central_directory_size);
+    LOGD("central footer @ %08X\n", out_index);
+
+    ok = 1;
+
+    free(central_directory_in);
+    free(central_directory_out);
+    return ok;
+}