tools/ota/make-update-script.c - android_bootable_recovery - Gitiles

 /*
  * Copyright (C) 2008 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #include "private/android_filesystem_config.h"

 #include <dirent.h>
 #include <limits.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <sys/types.h>
 #include <unistd.h>

 /*
  * Recursively walk the directory tree at <sysdir>/<subdir>, writing
  * script commands to set permissions and create symlinks.
  * Assume the contents already have the specified default permissions,
  * so only output commands if they need to be changed from the defaults.
  *
  * Note that permissions are set by fs_config(), which uses a lookup table of
  * Android permissions.  They are not drawn from the build host filesystem.
  */
 static void walk_files(
         const char *sysdir, const char *subdir,
         unsigned default_uid, unsigned default_gid,
         unsigned default_dir_mode, unsigned default_file_mode) {
     const char *sep = strcmp(subdir, "") ? "/" : "";

     char fn[PATH_MAX];
     unsigned dir_uid = 0, dir_gid = 0, dir_mode = 0;
     snprintf(fn, PATH_MAX, "system%s%s", sep, subdir);
     fs_config(fn, 1, &dir_uid, &dir_gid, &dir_mode);

     snprintf(fn, PATH_MAX, "%s%s%s", sysdir, sep, subdir);
     DIR *dir = opendir(fn);
     if (dir == NULL) {
         perror(fn);
         exit(1);
     }

     /*
      * We can use "set_perm" and "set_perm_recursive" to set file permissions
      * (owner, group, and file mode) for individual files and entire subtrees.
      * We want to use set_perm_recursive efficiently to avoid setting the
      * permissions of every single file in the system image individually.
      *
      * What we do is recursively set our entire subtree to the permissions
      * used by the first file we encounter, and then use "set_perm" to adjust
      * the permissions of subsequent files which don't match the first one.
      * This is bad if the first file is an outlier, but it generally works.
      * Subdirectories can do the same thing recursively if they're different.
      */

     int is_first = 1;
     const struct dirent *e;
     while ((e = readdir(dir))) {
         // Skip over "." and ".." entries
         if (!strcmp(e->d_name, ".") || !strcmp(e->d_name, "..")) continue;

         if (e->d_type == DT_LNK) {  // Symlink

             // Symlinks don't really have permissions, so this is orthogonal.
             snprintf(fn, PATH_MAX, "%s/%s%s%s", sysdir, subdir, sep, e->d_name);
             int len = readlink(fn, fn, PATH_MAX - 1);
             if (len <= 0) {
                 perror(fn);
                 exit(1);
             }
             fn[len] = '\0';
             printf("symlink %s SYSTEM:%s%s%s\n", fn, subdir, sep, e->d_name);

         } else if (e->d_type == DT_DIR) {  // Subdirectory

             // Use the parent directory as the model for default permissions.
             // We haven't seen a file, so just make up some file defaults.
             if (is_first && (
                     dir_mode != default_dir_mode ||
                     dir_uid != default_uid || dir_gid != default_gid)) {
                 default_uid = dir_uid;
                 default_gid = dir_gid;
                 default_dir_mode = dir_mode;
                 default_file_mode = dir_mode & default_file_mode & 0666;
                 printf("set_perm_recursive %d %d 0%o 0%o SYSTEM:%s\n",
                          default_uid, default_gid,
                          default_dir_mode, default_file_mode,
                          subdir);
             }

             is_first = 0;

             // Recursively handle the subdirectory.
             // Note, the recursive call handles the directory's own permissions.
             snprintf(fn, PATH_MAX, "%s%s%s", subdir, sep, e->d_name);
             walk_files(sysdir, fn,
                     default_uid, default_gid,
                     default_dir_mode, default_file_mode);

         } else {  // Ordinary file

             // Get the file's desired permissions.
             unsigned file_uid = 0, file_gid = 0, file_mode = 0;
             snprintf(fn, PATH_MAX, "system/%s%s%s", subdir, sep, e->d_name);
             fs_config(fn, 0, &file_uid, &file_gid, &file_mode);

             // If this is the first file, its mode gets to become the default.
             if (is_first && (
                     dir_mode != default_dir_mode ||
                     file_mode != default_file_mode ||
                     dir_uid != default_uid || file_uid != default_uid ||
                     dir_gid != default_gid || file_gid != default_gid)) {
                 default_uid = dir_uid;
                 default_gid = dir_gid;
                 default_dir_mode = dir_mode;
                 default_file_mode = file_mode;
                 printf("set_perm_recursive %d %d 0%o 0%o SYSTEM:%s\n",
                          default_uid, default_gid,
                          default_dir_mode, default_file_mode,
                          subdir);
             }

             is_first = 0;

             // Otherwise, override this file if it doesn't match the defaults.
             if (file_mode != default_file_mode ||
                 file_uid != default_uid || file_gid != default_gid) {
                 printf("set_perm %d %d 0%o SYSTEM:%s%s%s\n",
                          file_uid, file_gid, file_mode,
                          subdir, sep, e->d_name);
             }

         }
     }

     // Set the directory's permissions directly, if they never got set.
     if (dir_mode != default_dir_mode ||
         dir_uid != default_uid || dir_gid != default_gid) {
         printf("set_perm %d %d 0%o SYSTEM:%s\n",
                 dir_uid, dir_gid, dir_mode, subdir);
     }

     closedir(dir);
 }

 /*
  * Generate the update script (in "Amend", see commands/recovery/commands.c)
  * for the complete-reinstall OTA update packages the build system makes.
  *
  * The generated script makes a variety of sanity checks about the device,
  * erases and reinstalls system files, and sets file permissions appropriately.
  */
 int main(int argc, char *argv[]) {
     if (argc != 3) {
         fprintf(stderr, "usage: %s systemdir android-info.txt >update-script\n",
                 argv[0]);
         return 2;
     }

     // ensure basic recovery script language compatibility
     printf("assert compatible_with(\"0.2\") == \"true\"\n");

     // if known, make sure the device name is correct
     const char *device = getenv("TARGET_DEVICE");
     if (device != NULL) {
         printf("assert getprop(\"ro.product.device\") == \"%s\" || "
                 "getprop(\"ro.build.product\") == \"%s\"\n", device, device);
     }

     // scan android-info.txt to enforce compatibility with the target system
     FILE *fp = fopen(argv[2], "r");
     if (fp == NULL) {
         perror(argv[2]);
         return 1;
     }

     // The lines we're looking for look like:
     //     version-bootloader=x.yy.zzzz
     // or:
     //     require version-bootloader=x.yy.zzzz
     char line[256];
     while (fgets(line, sizeof(line), fp)) {
         const char *name = strtok(line, "="), *value = strtok(NULL, "\n");
         if (value != NULL &&
             (!strcmp(name, "version-bootloader") ||
              !strcmp(name, "require version-bootloader"))) {
             printf("assert getprop(\"ro.bootloader\") == \"%s\"\n", value);
         }
         // We also used to check version-baseband, but we update radio.img
         // ourselves, so there's no need.
     }

     // erase the boot sector first, so if the update gets interrupted,
     // the system will reboot into the recovery partition and start over.
     printf("format BOOT:\n");

     // write the radio image (actually just loads it into RAM for now)
     printf("show_progress 0.1 0\n");
     printf("write_radio_image PACKAGE:radio.img\n");

     // erase and reinstall the system image
     printf("show_progress 0.5 0\n");
     printf("format SYSTEM:\n");
     printf("copy_dir PACKAGE:system SYSTEM:\n");

     // walk the files in the system image, set their permissions, etc.
     // use -1 for default values to force permissions to be set explicitly.
     walk_files(argv[1], "", -1, -1, -1, -1);

     // as the last step, write the boot sector.
     printf("show_progress 0.2 0\n");
     printf("write_raw_image PACKAGE:boot.img BOOT:\n");

     // after the end of the script, the radio will be written to cache
     // leave some space in the progress bar for this operation
     printf("show_progress 0.2 10\n");
     return 0;
 }
	/*
	* Copyright (C) 2008 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#include "private/android_filesystem_config.h"

	#include <dirent.h>
	#include <limits.h>
	#include <stdio.h>
	#include <stdlib.h>
	#include <sys/types.h>
	#include <unistd.h>

	/*
	* Recursively walk the directory tree at <sysdir>/<subdir>, writing
	* script commands to set permissions and create symlinks.
	* Assume the contents already have the specified default permissions,
	* so only output commands if they need to be changed from the defaults.
	*
	* Note that permissions are set by fs_config(), which uses a lookup table of
	* Android permissions. They are not drawn from the build host filesystem.
	*/
	static void walk_files(
	const char sysdir, const char subdir,
	unsigned default_uid, unsigned default_gid,
	unsigned default_dir_mode, unsigned default_file_mode) {
	const char *sep = strcmp(subdir, "") ? "/" : "";

	char fn[PATH_MAX];
	unsigned dir_uid = 0, dir_gid = 0, dir_mode = 0;
	snprintf(fn, PATH_MAX, "system%s%s", sep, subdir);
	fs_config(fn, 1, &dir_uid, &dir_gid, &dir_mode);

	snprintf(fn, PATH_MAX, "%s%s%s", sysdir, sep, subdir);
	DIR *dir = opendir(fn);
	if (dir == NULL) {
	perror(fn);
	exit(1);
	}

	/*
	* We can use "set_perm" and "set_perm_recursive" to set file permissions
	* (owner, group, and file mode) for individual files and entire subtrees.
	* We want to use set_perm_recursive efficiently to avoid setting the
	* permissions of every single file in the system image individually.
	*
	* What we do is recursively set our entire subtree to the permissions
	* used by the first file we encounter, and then use "set_perm" to adjust
	* the permissions of subsequent files which don't match the first one.
	* This is bad if the first file is an outlier, but it generally works.
	* Subdirectories can do the same thing recursively if they're different.
	*/

	int is_first = 1;
	const struct dirent *e;
	while ((e = readdir(dir))) {
	// Skip over "." and ".." entries
	if (!strcmp(e->d_name, ".") \|\| !strcmp(e->d_name, "..")) continue;

	if (e->d_type == DT_LNK) { // Symlink

	// Symlinks don't really have permissions, so this is orthogonal.
	snprintf(fn, PATH_MAX, "%s/%s%s%s", sysdir, subdir, sep, e->d_name);
	int len = readlink(fn, fn, PATH_MAX - 1);
	if (len <= 0) {
	perror(fn);
	exit(1);
	}
	fn[len] = '\0';
	printf("symlink %s SYSTEM:%s%s%s\n", fn, subdir, sep, e->d_name);

	} else if (e->d_type == DT_DIR) { // Subdirectory

	// Use the parent directory as the model for default permissions.
	// We haven't seen a file, so just make up some file defaults.
	if (is_first && (
	dir_mode != default_dir_mode \|\|
	dir_uid != default_uid \|\| dir_gid != default_gid)) {
	default_uid = dir_uid;
	default_gid = dir_gid;
	default_dir_mode = dir_mode;
	default_file_mode = dir_mode & default_file_mode & 0666;
	printf("set_perm_recursive %d %d 0%o 0%o SYSTEM:%s\n",
	default_uid, default_gid,
	default_dir_mode, default_file_mode,
	subdir);
	}

	is_first = 0;

	// Recursively handle the subdirectory.
	// Note, the recursive call handles the directory's own permissions.
	snprintf(fn, PATH_MAX, "%s%s%s", subdir, sep, e->d_name);
	walk_files(sysdir, fn,
	default_uid, default_gid,
	default_dir_mode, default_file_mode);

	} else { // Ordinary file

	// Get the file's desired permissions.
	unsigned file_uid = 0, file_gid = 0, file_mode = 0;
	snprintf(fn, PATH_MAX, "system/%s%s%s", subdir, sep, e->d_name);
	fs_config(fn, 0, &file_uid, &file_gid, &file_mode);

	// If this is the first file, its mode gets to become the default.
	if (is_first && (
	dir_mode != default_dir_mode \|\|
	file_mode != default_file_mode \|\|
	dir_uid != default_uid \|\| file_uid != default_uid \|\|
	dir_gid != default_gid \|\| file_gid != default_gid)) {
	default_uid = dir_uid;
	default_gid = dir_gid;
	default_dir_mode = dir_mode;
	default_file_mode = file_mode;
	printf("set_perm_recursive %d %d 0%o 0%o SYSTEM:%s\n",
	default_uid, default_gid,
	default_dir_mode, default_file_mode,
	subdir);
	}

	is_first = 0;

	// Otherwise, override this file if it doesn't match the defaults.
	if (file_mode != default_file_mode \|\|
	file_uid != default_uid \|\| file_gid != default_gid) {
	printf("set_perm %d %d 0%o SYSTEM:%s%s%s\n",
	file_uid, file_gid, file_mode,
	subdir, sep, e->d_name);
	}

	}
	}

	// Set the directory's permissions directly, if they never got set.
	if (dir_mode != default_dir_mode \|\|
	dir_uid != default_uid \|\| dir_gid != default_gid) {
	printf("set_perm %d %d 0%o SYSTEM:%s\n",
	dir_uid, dir_gid, dir_mode, subdir);
	}

	closedir(dir);
	}

	/*
	* Generate the update script (in "Amend", see commands/recovery/commands.c)
	* for the complete-reinstall OTA update packages the build system makes.
	*
	* The generated script makes a variety of sanity checks about the device,
	* erases and reinstalls system files, and sets file permissions appropriately.
	*/
	int main(int argc, char *argv[]) {
	if (argc != 3) {
	fprintf(stderr, "usage: %s systemdir android-info.txt >update-script\n",
	argv[0]);
	return 2;
	}

	// ensure basic recovery script language compatibility
	printf("assert compatible_with(\"0.2\") == \"true\"\n");

	// if known, make sure the device name is correct
	const char *device = getenv("TARGET_DEVICE");
	if (device != NULL) {
	printf("assert getprop(\"ro.product.device\") == \"%s\" \|\| "
	"getprop(\"ro.build.product\") == \"%s\"\n", device, device);
	}

	// scan android-info.txt to enforce compatibility with the target system
	FILE *fp = fopen(argv[2], "r");
	if (fp == NULL) {
	perror(argv[2]);
	return 1;
	}

	// The lines we're looking for look like:
	// version-bootloader=x.yy.zzzz
	// or:
	// require version-bootloader=x.yy.zzzz
	char line[256];
	while (fgets(line, sizeof(line), fp)) {
	const char name = strtok(line, "="), value = strtok(NULL, "\n");
	if (value != NULL &&
	(!strcmp(name, "version-bootloader") \|\|
	!strcmp(name, "require version-bootloader"))) {
	printf("assert getprop(\"ro.bootloader\") == \"%s\"\n", value);
	}
	// We also used to check version-baseband, but we update radio.img
	// ourselves, so there's no need.
	}

	// erase the boot sector first, so if the update gets interrupted,
	// the system will reboot into the recovery partition and start over.
	printf("format BOOT:\n");

	// write the radio image (actually just loads it into RAM for now)
	printf("show_progress 0.1 0\n");
	printf("write_radio_image PACKAGE:radio.img\n");

	// erase and reinstall the system image
	printf("show_progress 0.5 0\n");
	printf("format SYSTEM:\n");
	printf("copy_dir PACKAGE:system SYSTEM:\n");

	// walk the files in the system image, set their permissions, etc.
	// use -1 for default values to force permissions to be set explicitly.
	walk_files(argv[1], "", -1, -1, -1, -1);

	// as the last step, write the boot sector.
	printf("show_progress 0.2 0\n");
	printf("write_raw_image PACKAGE:boot.img BOOT:\n");

	// after the end of the script, the radio will be written to cache
	// leave some space in the progress bar for this operation
	printf("show_progress 0.2 10\n");
	return 0;
	}