roots.c - platform/bootable/recovery - Git at Google

 /*
  * Copyright (C) 2007 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 <errno.h>
 #include <stdlib.h>
 #include <sys/mount.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <unistd.h>

 #include "mtdutils/mtdutils.h"
 #include "mtdutils/mounts.h"
 #include "minzip/Zip.h"
 #include "roots.h"
 #include "common.h"

 typedef struct {
     const char *name;
     const char *device;
     const char *device2;  // If the first one doesn't work (may be NULL)
     const char *partition_name;
     const char *mount_point;
     const char *filesystem;
 } RootInfo;

 /* Canonical pointers.
 xxx may just want to use enums
  */
 static const char g_mtd_device[] = "@\0g_mtd_device";
 static const char g_raw[] = "@\0g_raw";
 static const char g_package_file[] = "@\0g_package_file";

 static RootInfo g_roots[] = {
     { "BOOT:", g_mtd_device, NULL, "boot", NULL, g_raw },
     { "CACHE:", g_mtd_device, NULL, "cache", "/cache", "yaffs2" },
     { "DATA:", g_mtd_device, NULL, "userdata", "/data", "yaffs2" },
     { "MISC:", g_mtd_device, NULL, "misc", NULL, g_raw },
     { "PACKAGE:", NULL, NULL, NULL, NULL, g_package_file },
     { "RECOVERY:", g_mtd_device, NULL, "recovery", "/", g_raw },
     { "SDCARD:", "/dev/block/mmcblk0p1", "/dev/block/mmcblk0", NULL, "/sdcard", "vfat" },
     { "SYSTEM:", g_mtd_device, NULL, "system", "/system", "yaffs2" },
     { "MBM:", g_mtd_device, NULL, "mbm", NULL, g_raw },
     { "TMP:", NULL, NULL, NULL, "/tmp", NULL },
 };
 #define NUM_ROOTS (sizeof(g_roots) / sizeof(g_roots[0]))

 // TODO: for SDCARD:, try /dev/block/mmcblk0 if mmcblk0p1 fails

 static const RootInfo *
 get_root_info_for_path(const char *root_path)
 {
     const char *c;

     /* Find the first colon.
      */
     c = root_path;
     while (*c != '\0' && *c != ':') {
         c++;
     }
     if (*c == '\0') {
         return NULL;
     }
     size_t len = c - root_path + 1;
     size_t i;
     for (i = 0; i < NUM_ROOTS; i++) {
         RootInfo *info = &g_roots[i];
         if (strncmp(info->name, root_path, len) == 0) {
             return info;
         }
     }
     return NULL;
 }

 static const ZipArchive *g_package = NULL;
 static char *g_package_path = NULL;

 int
 register_package_root(const ZipArchive *package, const char *package_path)
 {
     if (package != NULL) {
         package_path = strdup(package_path);
         if (package_path == NULL) {
             return -1;
         }
         g_package_path = (char *)package_path;
     } else {
         free(g_package_path);
         g_package_path = NULL;
     }
     g_package = package;
     return 0;
 }

 int
 is_package_root_path(const char *root_path)
 {
     const RootInfo *info = get_root_info_for_path(root_path);
     return info != NULL && info->filesystem == g_package_file;
 }

 const char *
 translate_package_root_path(const char *root_path,
         char *out_buf, size_t out_buf_len, const ZipArchive **out_package)
 {
     const RootInfo *info = get_root_info_for_path(root_path);
     if (info == NULL || info->filesystem != g_package_file) {
         return NULL;
     }

     /* Strip the package root off of the path.
      */
     size_t root_len = strlen(info->name);
     root_path += root_len;
     size_t root_path_len = strlen(root_path);

     if (out_buf_len < root_path_len + 1) {
         return NULL;
     }
     strcpy(out_buf, root_path);
     *out_package = g_package;
     return out_buf;
 }

 /* Takes a string like "SYSTEM:lib" and turns it into a string
  * like "/system/lib".  The translated path is put in out_buf,
  * and out_buf is returned if the translation succeeded.
  */
 const char *
 translate_root_path(const char *root_path, char *out_buf, size_t out_buf_len)
 {
     if (out_buf_len < 1) {
         return NULL;
     }

     const RootInfo *info = get_root_info_for_path(root_path);
     if (info == NULL || info->mount_point == NULL) {
         return NULL;
     }

     /* Find the relative part of the non-root part of the path.
      */
     root_path += strlen(info->name);  // strip off the "root:"
     while (*root_path != '\0' && *root_path == '/') {
         root_path++;
     }

     size_t mp_len = strlen(info->mount_point);
     size_t rp_len = strlen(root_path);
     if (mp_len + 1 + rp_len + 1 > out_buf_len) {
         return NULL;
     }

     /* Glue the mount point to the relative part of the path.
      */
     memcpy(out_buf, info->mount_point, mp_len);
     if (out_buf[mp_len - 1] != '/') out_buf[mp_len++] = '/';

     memcpy(out_buf + mp_len, root_path, rp_len);
     out_buf[mp_len + rp_len] = '\0';

     return out_buf;
 }

 static int
 internal_root_mounted(const RootInfo *info)
 {
     if (info->mount_point == NULL) {
         return -1;
     }
 //xxx if TMP: (or similar) just say "yes"

     /* See if this root is already mounted.
      */
     int ret = scan_mounted_volumes();
     if (ret < 0) {
         return ret;
     }
     const MountedVolume *volume;
     volume = find_mounted_volume_by_mount_point(info->mount_point);
     if (volume != NULL) {
         /* It's already mounted.
          */
         return 0;
     }
     return -1;
 }

 int
 is_root_path_mounted(const char *root_path)
 {
     const RootInfo *info = get_root_info_for_path(root_path);
     if (info == NULL) {
         return -1;
     }
     return internal_root_mounted(info) >= 0;
 }

 int
 ensure_root_path_mounted(const char *root_path)
 {
     const RootInfo *info = get_root_info_for_path(root_path);
     if (info == NULL) {
         return -1;
     }

     int ret = internal_root_mounted(info);
     if (ret >= 0) {
         /* It's already mounted.
          */
         return 0;
     }

     /* It's not mounted.
      */
     if (info->device == g_mtd_device) {
         if (info->partition_name == NULL) {
             return -1;
         }
 //TODO: make the mtd stuff scan once when it needs to
         mtd_scan_partitions();
         const MtdPartition *partition;
         partition = mtd_find_partition_by_name(info->partition_name);
         if (partition == NULL) {
             return -1;
         }
         return mtd_mount_partition(partition, info->mount_point,
                 info->filesystem, 0);
     }

     if (info->device == NULL || info->mount_point == NULL ||
         info->filesystem == NULL ||
         info->filesystem == g_raw ||
         info->filesystem == g_package_file) {
         return -1;
     }

     mkdir(info->mount_point, 0755);  // in case it doesn't already exist
     if (mount(info->device, info->mount_point, info->filesystem,
             MS_NOATIME | MS_NODEV | MS_NODIRATIME, "")) {
         if (info->device2 == NULL) {
             LOGE("Can't mount %s\n(%s)\n", info->device, strerror(errno));
             return -1;
         } else if (mount(info->device2, info->mount_point, info->filesystem,
                 MS_NOATIME | MS_NODEV | MS_NODIRATIME, "")) {
             LOGE("Can't mount %s (or %s)\n(%s)\n",
                     info->device, info->device2, strerror(errno));
             return -1;
         }
     }
     return 0;
 }

 int
 ensure_root_path_unmounted(const char *root_path)
 {
     const RootInfo *info = get_root_info_for_path(root_path);
     if (info == NULL) {
         return -1;
     }
     if (info->mount_point == NULL) {
         /* This root can't be mounted, so by definition it isn't.
          */
         return 0;
     }
 //xxx if TMP: (or similar) just return error

     /* See if this root is already mounted.
      */
     int ret = scan_mounted_volumes();
     if (ret < 0) {
         return ret;
     }
     const MountedVolume *volume;
     volume = find_mounted_volume_by_mount_point(info->mount_point);
     if (volume == NULL) {
         /* It's not mounted.
          */
         return 0;
     }

     return unmount_mounted_volume(volume);
 }

 const MtdPartition *
 get_root_mtd_partition(const char *root_path)
 {
     const RootInfo *info = get_root_info_for_path(root_path);
     if (info == NULL || info->device != g_mtd_device ||
             info->partition_name == NULL)
     {
         return NULL;
     }
     mtd_scan_partitions();
     return mtd_find_partition_by_name(info->partition_name);
 }

 int
 format_root_device(const char *root)
 {
     /* Be a little safer here; require that "root" is just
      * a device with no relative path after it.
      */
     const char *c = root;
     while (*c != '\0' && *c != ':') {
         c++;
     }
     if (c[0] != ':' || c[1] != '\0') {
         LOGW("format_root_device: bad root name \"%s\"\n", root);
         return -1;
     }

     const RootInfo *info = get_root_info_for_path(root);
     if (info == NULL || info->device == NULL) {
         LOGW("format_root_device: can't resolve \"%s\"\n", root);
         return -1;
     }
     if (info->mount_point != NULL) {
         /* Don't try to format a mounted device.
          */
         int ret = ensure_root_path_unmounted(root);
         if (ret < 0) {
             LOGW("format_root_device: can't unmount \"%s\"\n", root);
             return ret;
         }
     }

     /* Format the device.
      */
     if (info->device == g_mtd_device) {
         mtd_scan_partitions();
         const MtdPartition *partition;
         partition = mtd_find_partition_by_name(info->partition_name);
         if (partition == NULL) {
             LOGW("format_root_device: can't find mtd partition \"%s\"\n",
                     info->partition_name);
             return -1;
         }
         if (info->filesystem == g_raw || !strcmp(info->filesystem, "yaffs2")) {
             MtdWriteContext *write = mtd_write_partition(partition);
             if (write == NULL) {
                 LOGW("format_root_device: can't open \"%s\"\n", root);
                 return -1;
             } else if (mtd_erase_blocks(write, -1) == (off_t) -1) {
                 LOGW("format_root_device: can't erase \"%s\"\n", root);
                 mtd_write_close(write);
                 return -1;
             } else if (mtd_write_close(write)) {
                 LOGW("format_root_device: can't close \"%s\"\n", root);
                 return -1;
             } else {
                 return 0;
             }
         }
     }
 //TODO: handle other device types (sdcard, etc.)
     LOGW("format_root_device: can't handle non-mtd device \"%s\"\n", root);
     return -1;
 }
	/*
	* Copyright (C) 2007 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 <errno.h>
	#include <stdlib.h>
	#include <sys/mount.h>
	#include <sys/stat.h>
	#include <sys/types.h>
	#include <unistd.h>

	#include "mtdutils/mtdutils.h"
	#include "mtdutils/mounts.h"
	#include "minzip/Zip.h"
	#include "roots.h"
	#include "common.h"

	typedef struct {
	const char *name;
	const char *device;
	const char *device2; // If the first one doesn't work (may be NULL)
	const char *partition_name;
	const char *mount_point;
	const char *filesystem;
	} RootInfo;

	/* Canonical pointers.
	xxx may just want to use enums
	*/
	static const char g_mtd_device[] = "@\0g_mtd_device";
	static const char g_raw[] = "@\0g_raw";
	static const char g_package_file[] = "@\0g_package_file";

	static RootInfo g_roots[] = {
	{ "BOOT:", g_mtd_device, NULL, "boot", NULL, g_raw },
	{ "CACHE:", g_mtd_device, NULL, "cache", "/cache", "yaffs2" },
	{ "DATA:", g_mtd_device, NULL, "userdata", "/data", "yaffs2" },
	{ "MISC:", g_mtd_device, NULL, "misc", NULL, g_raw },
	{ "PACKAGE:", NULL, NULL, NULL, NULL, g_package_file },
	{ "RECOVERY:", g_mtd_device, NULL, "recovery", "/", g_raw },
	{ "SDCARD:", "/dev/block/mmcblk0p1", "/dev/block/mmcblk0", NULL, "/sdcard", "vfat" },
	{ "SYSTEM:", g_mtd_device, NULL, "system", "/system", "yaffs2" },
	{ "MBM:", g_mtd_device, NULL, "mbm", NULL, g_raw },
	{ "TMP:", NULL, NULL, NULL, "/tmp", NULL },
	};
	#define NUM_ROOTS (sizeof(g_roots) / sizeof(g_roots[0]))

	// TODO: for SDCARD:, try /dev/block/mmcblk0 if mmcblk0p1 fails

	static const RootInfo *
	get_root_info_for_path(const char *root_path)
	{
	const char *c;

	/* Find the first colon.
	*/
	c = root_path;
	while (c != '\0' && c != ':') {
	c++;
	}
	if (*c == '\0') {
	return NULL;
	}
	size_t len = c - root_path + 1;
	size_t i;
	for (i = 0; i < NUM_ROOTS; i++) {
	RootInfo *info = &g_roots[i];
	if (strncmp(info->name, root_path, len) == 0) {
	return info;
	}
	}
	return NULL;
	}

	static const ZipArchive *g_package = NULL;
	static char *g_package_path = NULL;

	int
	register_package_root(const ZipArchive package, const char package_path)
	{
	if (package != NULL) {
	package_path = strdup(package_path);
	if (package_path == NULL) {
	return -1;
	}
	g_package_path = (char *)package_path;
	} else {
	free(g_package_path);
	g_package_path = NULL;
	}
	g_package = package;
	return 0;
	}

	int
	is_package_root_path(const char *root_path)
	{
	const RootInfo *info = get_root_info_for_path(root_path);
	return info != NULL && info->filesystem == g_package_file;
	}

	const char *
	translate_package_root_path(const char *root_path,
	char out_buf, size_t out_buf_len, const ZipArchive *out_package)
	{
	const RootInfo *info = get_root_info_for_path(root_path);
	if (info == NULL \|\| info->filesystem != g_package_file) {
	return NULL;
	}

	/* Strip the package root off of the path.
	*/
	size_t root_len = strlen(info->name);
	root_path += root_len;
	size_t root_path_len = strlen(root_path);

	if (out_buf_len < root_path_len + 1) {
	return NULL;
	}
	strcpy(out_buf, root_path);
	*out_package = g_package;
	return out_buf;
	}

	/* Takes a string like "SYSTEM:lib" and turns it into a string
	* like "/system/lib". The translated path is put in out_buf,
	* and out_buf is returned if the translation succeeded.
	*/
	const char *
	translate_root_path(const char root_path, char out_buf, size_t out_buf_len)
	{
	if (out_buf_len < 1) {
	return NULL;
	}

	const RootInfo *info = get_root_info_for_path(root_path);
	if (info == NULL \|\| info->mount_point == NULL) {
	return NULL;
	}

	/* Find the relative part of the non-root part of the path.
	*/
	root_path += strlen(info->name); // strip off the "root:"
	while (root_path != '\0' && root_path == '/') {
	root_path++;
	}

	size_t mp_len = strlen(info->mount_point);
	size_t rp_len = strlen(root_path);
	if (mp_len + 1 + rp_len + 1 > out_buf_len) {
	return NULL;
	}

	/* Glue the mount point to the relative part of the path.
	*/
	memcpy(out_buf, info->mount_point, mp_len);
	if (out_buf[mp_len - 1] != '/') out_buf[mp_len++] = '/';

	memcpy(out_buf + mp_len, root_path, rp_len);
	out_buf[mp_len + rp_len] = '\0';

	return out_buf;
	}

	static int
	internal_root_mounted(const RootInfo *info)
	{
	if (info->mount_point == NULL) {
	return -1;
	}
	//xxx if TMP: (or similar) just say "yes"

	/* See if this root is already mounted.
	*/
	int ret = scan_mounted_volumes();
	if (ret < 0) {
	return ret;
	}
	const MountedVolume *volume;
	volume = find_mounted_volume_by_mount_point(info->mount_point);
	if (volume != NULL) {
	/* It's already mounted.
	*/
	return 0;
	}
	return -1;
	}

	int
	is_root_path_mounted(const char *root_path)
	{
	const RootInfo *info = get_root_info_for_path(root_path);
	if (info == NULL) {
	return -1;
	}
	return internal_root_mounted(info) >= 0;
	}

	int
	ensure_root_path_mounted(const char *root_path)
	{
	const RootInfo *info = get_root_info_for_path(root_path);
	if (info == NULL) {
	return -1;
	}

	int ret = internal_root_mounted(info);
	if (ret >= 0) {
	/* It's already mounted.
	*/
	return 0;
	}

	/* It's not mounted.
	*/
	if (info->device == g_mtd_device) {
	if (info->partition_name == NULL) {
	return -1;
	}
	//TODO: make the mtd stuff scan once when it needs to
	mtd_scan_partitions();
	const MtdPartition *partition;
	partition = mtd_find_partition_by_name(info->partition_name);
	if (partition == NULL) {
	return -1;
	}
	return mtd_mount_partition(partition, info->mount_point,
	info->filesystem, 0);
	}

	if (info->device == NULL \|\| info->mount_point == NULL \|\|
	info->filesystem == NULL \|\|
	info->filesystem == g_raw \|\|
	info->filesystem == g_package_file) {
	return -1;
	}

	mkdir(info->mount_point, 0755); // in case it doesn't already exist
	if (mount(info->device, info->mount_point, info->filesystem,
	MS_NOATIME \| MS_NODEV \| MS_NODIRATIME, "")) {
	if (info->device2 == NULL) {
	LOGE("Can't mount %s\n(%s)\n", info->device, strerror(errno));
	return -1;
	} else if (mount(info->device2, info->mount_point, info->filesystem,
	MS_NOATIME \| MS_NODEV \| MS_NODIRATIME, "")) {
	LOGE("Can't mount %s (or %s)\n(%s)\n",
	info->device, info->device2, strerror(errno));
	return -1;
	}
	}
	return 0;
	}

	int
	ensure_root_path_unmounted(const char *root_path)
	{
	const RootInfo *info = get_root_info_for_path(root_path);
	if (info == NULL) {
	return -1;
	}
	if (info->mount_point == NULL) {
	/* This root can't be mounted, so by definition it isn't.
	*/
	return 0;
	}
	//xxx if TMP: (or similar) just return error

	/* See if this root is already mounted.
	*/
	int ret = scan_mounted_volumes();
	if (ret < 0) {
	return ret;
	}
	const MountedVolume *volume;
	volume = find_mounted_volume_by_mount_point(info->mount_point);
	if (volume == NULL) {
	/* It's not mounted.
	*/
	return 0;
	}

	return unmount_mounted_volume(volume);
	}

	const MtdPartition *
	get_root_mtd_partition(const char *root_path)
	{
	const RootInfo *info = get_root_info_for_path(root_path);
	if (info == NULL \|\| info->device != g_mtd_device \|\|
	info->partition_name == NULL)
	{
	return NULL;
	}
	mtd_scan_partitions();
	return mtd_find_partition_by_name(info->partition_name);
	}

	int
	format_root_device(const char *root)
	{
	/* Be a little safer here; require that "root" is just
	* a device with no relative path after it.
	*/
	const char *c = root;
	while (c != '\0' && c != ':') {
	c++;
	}
	if (c[0] != ':' \|\| c[1] != '\0') {
	LOGW("format_root_device: bad root name \"%s\"\n", root);
	return -1;
	}

	const RootInfo *info = get_root_info_for_path(root);
	if (info == NULL \|\| info->device == NULL) {
	LOGW("format_root_device: can't resolve \"%s\"\n", root);
	return -1;
	}
	if (info->mount_point != NULL) {
	/* Don't try to format a mounted device.
	*/
	int ret = ensure_root_path_unmounted(root);
	if (ret < 0) {
	LOGW("format_root_device: can't unmount \"%s\"\n", root);
	return ret;
	}
	}

	/* Format the device.
	*/
	if (info->device == g_mtd_device) {
	mtd_scan_partitions();
	const MtdPartition *partition;
	partition = mtd_find_partition_by_name(info->partition_name);
	if (partition == NULL) {
	LOGW("format_root_device: can't find mtd partition \"%s\"\n",
	info->partition_name);
	return -1;
	}
	if (info->filesystem == g_raw \|\| !strcmp(info->filesystem, "yaffs2")) {
	MtdWriteContext *write = mtd_write_partition(partition);
	if (write == NULL) {
	LOGW("format_root_device: can't open \"%s\"\n", root);
	return -1;
	} else if (mtd_erase_blocks(write, -1) == (off_t) -1) {
	LOGW("format_root_device: can't erase \"%s\"\n", root);
	mtd_write_close(write);
	return -1;
	} else if (mtd_write_close(write)) {
	LOGW("format_root_device: can't close \"%s\"\n", root);
	return -1;
	} else {
	return 0;
	}
	}
	}
	//TODO: handle other device types (sdcard, etc.)
	LOGW("format_root_device: can't handle non-mtd device \"%s\"\n", root);
	return -1;
	}