From 47c3ee9725a835ea9aed82513fd278f6ca2dff0a Mon Sep 17 00:00:00 2001 From: Badhri Jagan Sridharan Date: Mon, 21 Mar 2016 10:55:23 -0700 Subject: [PATCH] ANDROID: dm: android-verity: Mounting root as linear device when verity disabled This CL makes android-verity target to be added as linear dm device if when bootloader is unlocked and verity is disabled. Bug: 27175947 Change-Id: Ic41ca4b8908fb2777263799cf3a3e25934d70f18 Signed-off-by: Badhri Jagan Sridharan [AmitP: Folded following android-4.9 commit changes into this patch 7e70218c2699 ("ANDROID: dm: Minor cleanup") 67584ff8412b ("ANDROID: dm: rename dm-linear methods for dm-android-verity")] Signed-off-by: Amit Pundir --- drivers/md/dm-android-verity.c | 128 +++++++++++++++++++++++++++------ drivers/md/dm-android-verity.h | 17 +++++ drivers/md/dm-linear.c | 24 +++---- 3 files changed, 135 insertions(+), 34 deletions(-) diff --git a/drivers/md/dm-android-verity.c b/drivers/md/dm-android-verity.c index aeb5045830d9..b7e059595f75 100644 --- a/drivers/md/dm-android-verity.c +++ b/drivers/md/dm-android-verity.c @@ -13,6 +13,7 @@ */ #include +#include #include #include #include @@ -43,6 +44,25 @@ static char verifiedbootstate[VERITY_COMMANDLINE_PARAM_LENGTH]; static char veritymode[VERITY_COMMANDLINE_PARAM_LENGTH]; +static bool target_added; +static bool verity_enabled = true; +struct dentry *debug_dir; +static int android_verity_ctr(struct dm_target *ti, unsigned argc, char **argv); + +static struct target_type android_verity_target = { + .name = "android-verity", + .version = {1, 0, 0}, + .module = THIS_MODULE, + .ctr = android_verity_ctr, + .dtr = verity_dtr, + .map = verity_map, + .status = verity_status, + .ioctl = verity_ioctl, + .merge = verity_merge, + .iterate_devices = verity_iterate_devices, + .io_hints = verity_io_hints, +}; + static int __init verified_boot_state_param(char *line) { strlcpy(verifiedbootstate, line, sizeof(verifiedbootstate)); @@ -549,6 +569,32 @@ static inline bool test_mult_overflow(sector_t a, u32 b) return a > r; } +static int add_as_linear_device(struct dm_target *ti, char *dev) +{ + /*Move to linear mapping defines*/ + char *linear_table_args[DM_LINEAR_ARGS] = {dev, + DM_LINEAR_TARGET_OFFSET}; + int err = 0; + + android_verity_target.dtr = dm_linear_dtr, + android_verity_target.map = dm_linear_map, + android_verity_target.status = dm_linear_status, + android_verity_target.ioctl = dm_linear_ioctl, + android_verity_target.merge = dm_linear_merge, + android_verity_target.iterate_devices = dm_linear_iterate_devices, + android_verity_target.io_hints = NULL; + + err = dm_linear_ctr(ti, DM_LINEAR_ARGS, linear_table_args); + + if (!err) { + DMINFO("Added android-verity as a linear target"); + target_added = true; + } else + DMERR("Failed to add android-verity as linear target"); + + return err; +} + /* * Target parameters: * Key id of the public key in the system keyring. @@ -613,21 +659,27 @@ static int android_verity_ctr(struct dm_target *ti, unsigned argc, char **argv) if (err == VERITY_STATE_DISABLE) { DMERR("Mounting root with verity disabled"); - return -EINVAL; + verity_enabled = false; + /* we would still have to parse the args to figure out + * the data blocks size. Or may be could map the entire + * partition similar to mounting the device. + */ } else if (err) { DMERR("Verity header handle error"); handle_error(); goto free_metadata; } - err = verify_verity_signature(key_id, metadata); + if (!verity_enabled) { + err = verify_verity_signature(key_id, metadata); - if (err) { - DMERR("Signature verification failed"); - handle_error(); - goto free_metadata; - } else - DMINFO("Signature verification success"); + if (err) { + DMERR("Signature verification failed"); + handle_error(); + goto free_metadata; + } else + DMINFO("Signature verification success"); + } table_ptr = metadata->verity_table; @@ -683,6 +735,12 @@ static int android_verity_ctr(struct dm_target *ti, unsigned argc, char **argv) /* update target length */ ti->len = data_sectors; + /* Setup linear target and free */ + if (!verity_enabled) { + err = add_as_linear_device(ti, argv[1]); + goto free_metadata; + } + /*substitute data_dev and hash_dev*/ verity_table_args[1] = argv[1]; verity_table_args[2] = argv[1]; @@ -730,6 +788,13 @@ static int android_verity_ctr(struct dm_target *ti, unsigned argc, char **argv) err = verity_ctr(ti, no_of_args, verity_table_args); + if (err) + DMERR("android-verity failed to mount as verity target"); + else { + target_added = true; + DMINFO("android-verity mounted as verity target"); + } + free_metadata: kfree(metadata->header); kfree(metadata->verity_table); @@ -737,33 +802,52 @@ free_metadata: return err; } -static struct target_type android_verity_target = { - .name = "android-verity", - .version = {1, 0, 0}, - .module = THIS_MODULE, - .ctr = android_verity_ctr, - .dtr = verity_dtr, - .map = verity_map, - .status = verity_status, - .ioctl = verity_ioctl, - .merge = verity_merge, - .iterate_devices = verity_iterate_devices, - .io_hints = verity_io_hints, -}; - static int __init dm_android_verity_init(void) { int r; + struct dentry *file; r = dm_register_target(&android_verity_target); if (r < 0) DMERR("register failed %d", r); + /* Tracks the status of the last added target */ + debug_dir = debugfs_create_dir("android_verity", NULL); + + if (IS_ERR_OR_NULL(debug_dir)) { + DMERR("Cannot create android_verity debugfs directory: %ld", + PTR_ERR(debug_dir)); + goto end; + } + + file = debugfs_create_bool("target_added", S_IRUGO, debug_dir, + (u32 *)&target_added); + + if (IS_ERR_OR_NULL(file)) { + DMERR("Cannot create android_verity debugfs directory: %ld", + PTR_ERR(debug_dir)); + debugfs_remove_recursive(debug_dir); + goto end; + } + + file = debugfs_create_bool("verity_enabled", S_IRUGO, debug_dir, + (u32 *)&verity_enabled); + + if (IS_ERR_OR_NULL(file)) { + DMERR("Cannot create android_verity debugfs directory: %ld", + PTR_ERR(debug_dir)); + debugfs_remove_recursive(debug_dir); + } + +end: return r; } static void __exit dm_android_verity_exit(void) { + if (!IS_ERR_OR_NULL(debug_dir)) + debugfs_remove_recursive(debug_dir); + dm_unregister_target(&android_verity_target); } diff --git a/drivers/md/dm-android-verity.h b/drivers/md/dm-android-verity.h index 11477ffd2243..efb796524896 100644 --- a/drivers/md/dm-android-verity.h +++ b/drivers/md/dm-android-verity.h @@ -44,6 +44,10 @@ #define VERITY_DEBUG 0 #define DM_MSG_PREFIX "android-verity" + +#define DM_LINEAR_ARGS 2 +#define DM_LINEAR_TARGET_OFFSET "0" + /* * There can be two formats. * if fec is present @@ -89,4 +93,17 @@ struct bio_read { int number_of_pages; }; +extern struct target_type linear_target; + +extern void dm_linear_dtr(struct dm_target *ti); +extern int dm_linear_map(struct dm_target *ti, struct bio *bio); +extern void dm_linear_status(struct dm_target *ti, status_type_t type, + unsigned status_flags, char *result, unsigned maxlen); +extern int dm_linear_ioctl(struct dm_target *ti, unsigned int cmd, + unsigned long arg); +extern int dm_linear_merge(struct dm_target *ti, struct bvec_merge_data *bvm, + struct bio_vec *biovec, int max_size); +extern int dm_linear_iterate_devices(struct dm_target *ti, + iterate_devices_callout_fn fn, void *data); +extern int dm_linear_ctr(struct dm_target *ti, unsigned int argc, char **argv); #endif /* DM_ANDROID_VERITY_H */ diff --git a/drivers/md/dm-linear.c b/drivers/md/dm-linear.c index d5f8eff7c11d..9ac433096a04 100644 --- a/drivers/md/dm-linear.c +++ b/drivers/md/dm-linear.c @@ -26,7 +26,7 @@ struct linear_c { /* * Construct a linear mapping: */ -static int linear_ctr(struct dm_target *ti, unsigned int argc, char **argv) +int dm_linear_ctr(struct dm_target *ti, unsigned int argc, char **argv) { struct linear_c *lc; unsigned long long tmp; @@ -69,7 +69,7 @@ static int linear_ctr(struct dm_target *ti, unsigned int argc, char **argv) return ret; } -static void linear_dtr(struct dm_target *ti) +void dm_linear_dtr(struct dm_target *ti) { struct linear_c *lc = (struct linear_c *) ti->private; @@ -94,7 +94,7 @@ static void linear_map_bio(struct dm_target *ti, struct bio *bio) linear_map_sector(ti, bio->bi_iter.bi_sector); } -static int linear_map(struct dm_target *ti, struct bio *bio) +int dm_linear_map(struct dm_target *ti, struct bio *bio) { linear_map_bio(ti, bio); @@ -112,7 +112,7 @@ static int linear_end_io(struct dm_target *ti, struct bio *bio, return DM_ENDIO_DONE; } -static void linear_status(struct dm_target *ti, status_type_t type, +void dm_linear_status(struct dm_target *ti, status_type_t type, unsigned status_flags, char *result, unsigned maxlen) { struct linear_c *lc = (struct linear_c *) ti->private; @@ -129,7 +129,7 @@ static void linear_status(struct dm_target *ti, status_type_t type, } } -static int linear_prepare_ioctl(struct dm_target *ti, +static int dm_linear_prepare_ioctl(struct dm_target *ti, struct block_device **bdev, fmode_t *mode) { struct linear_c *lc = (struct linear_c *) ti->private; @@ -146,7 +146,7 @@ static int linear_prepare_ioctl(struct dm_target *ti, return 0; } -static int linear_iterate_devices(struct dm_target *ti, +int dm_linear_iterate_devices(struct dm_target *ti, iterate_devices_callout_fn fn, void *data) { struct linear_c *lc = ti->private; @@ -189,13 +189,13 @@ static struct target_type linear_target = { .version = {1, 4, 0}, .features = DM_TARGET_PASSES_INTEGRITY | DM_TARGET_ZONED_HM, .module = THIS_MODULE, - .ctr = linear_ctr, - .dtr = linear_dtr, - .map = linear_map, + .ctr = dm_linear_ctr, + .dtr = dm_linear_dtr, + .map = dm_linear_map, + .status = dm_linear_status, .end_io = linear_end_io, - .status = linear_status, - .prepare_ioctl = linear_prepare_ioctl, - .iterate_devices = linear_iterate_devices, + .prepare_ioctl = dm_linear_prepare_ioctl, + .iterate_devices = dm_linear_iterate_devices, .direct_access = linear_dax_direct_access, .dax_copy_from_iter = linear_dax_copy_from_iter, }; -- 2.20.1