Message ID | 20221203031702.579790-1-jassisinghbrar@gmail.com |
---|---|
State | Superseded |
Headers | show |
Series | FWU: Handle meta-data in common code | expand |
Hello Jassi, On Sat, 3 Dec 2022 at 04:17, <jassisinghbrar@gmail.com> wrote: > > From: Jassi Brar <jaswinder.singh@linaro.org> > > Instead of each i/f having to implement their own meta-data verification > and storage, move the logic in common code. This simplifies the i/f code > much simpler and compact. > > Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org> > --- > drivers/fwu-mdata/fwu-mdata-uclass.c | 34 +++++++ > include/fwu.h | 41 ++++++++ > lib/fwu_updates/fwu.c | 143 ++++++++++++++++++++++++++- > 3 files changed, 214 insertions(+), 4 deletions(-) > > diff --git a/drivers/fwu-mdata/fwu-mdata-uclass.c b/drivers/fwu-mdata/fwu-mdata-uclass.c > index b477e9603f..e03773c584 100644 > --- a/drivers/fwu-mdata/fwu-mdata-uclass.c > +++ b/drivers/fwu-mdata/fwu-mdata-uclass.c > @@ -16,6 +16,40 @@ > #include <linux/types.h> > #include <u-boot/crc.h> > > +/** > + * fwu_read_mdata() - Wrapper around fwu_mdata_ops.read_mdata() > + * > + * Return: 0 if OK, -ve on error > + */ > +int fwu_read_mdata(struct udevice *dev, struct fwu_mdata *mdata, bool primary) > +{ > + const struct fwu_mdata_ops *ops = device_get_ops(dev); > + > + if (!ops->read_mdata) { > + log_debug("read_mdata() method not defined\n"); > + return -ENOSYS; > + } > + > + return ops->read_mdata(dev, mdata, primary); > +} > + > +/** > + * fwu_write_mdata() - Wrapper around fwu_mdata_ops.write_mdata() > + * > + * Return: 0 if OK, -ve on error > + */ > +int fwu_write_mdata(struct udevice *dev, struct fwu_mdata *mdata, bool primary) > +{ > + const struct fwu_mdata_ops *ops = device_get_ops(dev); > + > + if (!ops->write_mdata) { > + log_debug("write_mdata() method not defined\n"); > + return -ENOSYS; > + } > + > + return ops->write_mdata(dev, mdata, primary); > +} > + > /** > * fwu_get_mdata_part_num() - Get the FWU metadata partition numbers > * @dev: FWU metadata device > diff --git a/include/fwu.h b/include/fwu.h > index 0919ced812..1a700c9e6a 100644 > --- a/include/fwu.h > +++ b/include/fwu.h > @@ -24,6 +24,26 @@ struct fwu_mdata_gpt_blk_priv { > * @update_mdata() - Update the FWU metadata copy > */ > struct fwu_mdata_ops { > + /** > + * read_mdata() - Populate the asked FWU metadata copy > + * @dev: FWU metadata device > + * @mdata: Copy of the FWU metadata > + * @primary: If primary or secondary copy of meta-data is to be read > + * > + * Return: 0 if OK, -ve on error > + */ > + int (*read_mdata)(struct udevice *dev, struct fwu_mdata *mdata, bool primary); > + > + /** > + * write_mdata() - Write the given FWU metadata copy > + * @dev: FWU metadata device > + * @mdata: Copy of the FWU metadata > + * @primary: If primary or secondary copy of meta-data is to be written > + * > + * Return: 0 if OK, -ve on error > + */ > + int (*write_mdata)(struct udevice *dev, struct fwu_mdata *mdata, bool primary); > + > /** > * check_mdata() - Check if the FWU metadata is valid > * @dev: FWU device > @@ -126,6 +146,27 @@ struct fwu_mdata_ops { > EFI_GUID(0x0c996046, 0xbcc0, 0x4d04, 0x85, 0xec, \ > 0xe1, 0xfc, 0xed, 0xf1, 0xc6, 0xf8) > > +/** > + * fwu_read_mdata() - Wrapper around fwu_mdata_ops.read_mdata() > + */ > +int fwu_read_mdata(struct udevice *dev, struct fwu_mdata *mdata, bool primary); > + > +/** > + * fwu_write_mdata() - Wrapper around fwu_mdata_ops.write_mdata() > + */ > +int fwu_write_mdata(struct udevice *dev, struct fwu_mdata *mdata, bool primary); > + > +/** > + * fwu_get_verified_mdata() - Read, verify and return the FWU metadata > + * > + * Read both the metadata copies from the storage media, verify their checksum, > + * and ascertain that both copies match. If one of the copies has gone bad, > + * restore it from the good copy. > + * > + * Return: 0 if OK, -ve on error > +*/ > +int fwu_get_verified_mdata(struct fwu_mdata *mdata); > + > /** > * fwu_check_mdata_validity() - Check for validity of the FWU metadata copies > * > diff --git a/lib/fwu_updates/fwu.c b/lib/fwu_updates/fwu.c > index 5313d07302..f17bd8ea63 100644 > --- a/lib/fwu_updates/fwu.c > +++ b/lib/fwu_updates/fwu.c > @@ -15,13 +15,13 @@ > #include <linux/errno.h> > #include <linux/types.h> > > +#include <u-boot/crc.h> > + > +static struct fwu_mdata g_mdata; /* = {0} makes uninit crc32 always invalid */ > +static struct udevice *g_dev; > static u8 in_trial; > static u8 boottime_check; > > -#include <linux/errno.h> > -#include <linux/types.h> > -#include <u-boot/crc.h> > - > enum { > IMAGE_ACCEPT_SET = 1, > IMAGE_ACCEPT_CLEAR, > @@ -161,6 +161,141 @@ static int fwu_get_image_type_id(u8 *image_index, efi_guid_t *image_type_id) > return -ENOENT; > } > > +/** > + * fwu_sync_mdata() - Update given meta-data partition(s) with the copy provided > + * @mdata: FWU metadata structure > + * @part: Bitmask of FWU metadata partitions to be written to > + * > + * Return: 0 if OK, -ve on error > + */ > +static int fwu_sync_mdata(struct fwu_mdata *mdata, int part) > +{ > + void *buf = &mdata->version; > + int err = 0; > + > + /* > + * Calculate the crc32 for the updated FWU metadata > + * and put the updated value in the FWU metadata crc32 > + * field > + */ > + mdata->crc32 = crc32(0, buf, sizeof(*mdata) - sizeof(u32)); > + > + if (part & PRIMARY_PART) > + err = fwu_write_mdata(g_dev, mdata, true); > + > + if (err) { > + log_err("Unable to write primary mdata\n"); > + return err; > + } > + > + if (part & SECONDARY_PART) > + err = fwu_write_mdata(g_dev, mdata, false); > + > + if (err) { > + log_err("Unable to write secondary mdata\n"); > + return err; > + } > + > + /* update the cached copy of meta-data */ > + memcpy(&g_mdata, mdata, sizeof(struct fwu_mdata)); > + > + return 0; > +} > + > +static inline int mdata_crc_check(struct fwu_mdata *mdata) > +{ > + void *buf = &mdata->version; > + u32 calc_crc32 = crc32(0, buf, sizeof(*mdata) - sizeof(u32)); > + > + return calc_crc32 == mdata->crc32 ? 0 : -EINVAL; > +} > + > +/** > + * fwu_get_verified_mdata() - Read, verify and return the FWU metadata > + * > + * Read both the metadata copies from the storage media, verify their checksum, > + * and ascertain that both copies match. If one of the copies has gone bad, > + * restore it from the good copy. > + * > + * Return: 0 if OK, -ve on error > + */ > +int fwu_get_verified_mdata(struct fwu_mdata *mdata) > +{ > + int err; > + bool pri_ok, sec_ok; > + struct fwu_mdata s, *p_mdata, *s_mdata; > + > + p_mdata = &g_mdata; > + s_mdata = &s; > + > + /* if mdata already read and ready */ > + err = mdata_crc_check(p_mdata); > + if (!err) { > + if (mdata) > + memcpy(mdata, p_mdata, sizeof(struct fwu_mdata)); > + return 0; > + } > + /* else read, verify and, if needed, fix mdata */ > + > + pri_ok = false; > + err = fwu_read_mdata(g_dev, p_mdata, true); > + if (!err) { > + err = mdata_crc_check(p_mdata); > + if (!err) > + pri_ok = true; > + else > + log_debug("primary mdata: crc32 failed\n"); > + } > + > + sec_ok = false; > + err = fwu_read_mdata(g_dev, s_mdata, false); > + if (!err) { > + err = mdata_crc_check(s_mdata); > + if (!err) > + sec_ok = true; > + else > + log_debug("secondary mdata: crc32 failed\n"); > + } > + > + if (pri_ok && sec_ok) { > + /* > + * Before returning, check that both the > + * FWU metadata copies are the same. > + */ > + err = memcmp(p_mdata, s_mdata, sizeof(struct fwu_mdata)); > + if (!err) > + return 0; Copy of the metadata to @mdata is missing here and in success path before exit_fix branch label. regards, etienne > + > + /* > + * If not, populate the secondary partition from the > + * primary partition copy. > + */ > + log_info("Both FWU metadata copies are valid but do not match."); > + log_info(" Restoring the secondary partition from the primary\n"); > + sec_ok = false; > + } > + > + if (!pri_ok) { > + memcpy(p_mdata, s_mdata, sizeof(struct fwu_mdata)); > + err = fwu_sync_mdata(p_mdata, PRIMARY_PART); > + if (err) > + goto exit_fix; > + } > + > + if (!sec_ok) { > + memcpy(s_mdata, p_mdata, sizeof(struct fwu_mdata)); > + err = fwu_sync_mdata(s_mdata, SECONDARY_PART); > + if (err) > + goto exit_fix; > + } > + > +exit_fix: > + if (err) > + log_debug("mdata saving : crc32 failed\n"); > + > + return err; > +} > + > /** > * fwu_verify_mdata() - Verify the FWU metadata > * @mdata: FWU metadata structure > -- > 2.34.1 >
On Tue, 13 Dec 2022 at 09:00, Etienne Carriere <etienne.carriere@linaro.org> wrote: > > Hello Jassi, > > On Sat, 3 Dec 2022 at 04:17, <jassisinghbrar@gmail.com> wrote: > > > > From: Jassi Brar <jaswinder.singh@linaro.org> > > > > Instead of each i/f having to implement their own meta-data verification > > and storage, move the logic in common code. This simplifies the i/f code > > much simpler and compact. > > > > Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org> > > --- > > drivers/fwu-mdata/fwu-mdata-uclass.c | 34 +++++++ > > include/fwu.h | 41 ++++++++ > > lib/fwu_updates/fwu.c | 143 ++++++++++++++++++++++++++- > > 3 files changed, 214 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/fwu-mdata/fwu-mdata-uclass.c b/drivers/fwu-mdata/fwu-mdata-uclass.c > > index b477e9603f..e03773c584 100644 > > --- a/drivers/fwu-mdata/fwu-mdata-uclass.c > > +++ b/drivers/fwu-mdata/fwu-mdata-uclass.c > > @@ -16,6 +16,40 @@ > > #include <linux/types.h> > > #include <u-boot/crc.h> > > > > +/** > > + * fwu_read_mdata() - Wrapper around fwu_mdata_ops.read_mdata() > > + * > > + * Return: 0 if OK, -ve on error > > + */ > > +int fwu_read_mdata(struct udevice *dev, struct fwu_mdata *mdata, bool primary) > > +{ > > + const struct fwu_mdata_ops *ops = device_get_ops(dev); > > + > > + if (!ops->read_mdata) { > > + log_debug("read_mdata() method not defined\n"); > > + return -ENOSYS; > > + } > > + > > + return ops->read_mdata(dev, mdata, primary); > > +} > > + > > +/** > > + * fwu_write_mdata() - Wrapper around fwu_mdata_ops.write_mdata() > > + * > > + * Return: 0 if OK, -ve on error > > + */ > > +int fwu_write_mdata(struct udevice *dev, struct fwu_mdata *mdata, bool primary) > > +{ > > + const struct fwu_mdata_ops *ops = device_get_ops(dev); > > + > > + if (!ops->write_mdata) { > > + log_debug("write_mdata() method not defined\n"); > > + return -ENOSYS; > > + } > > + > > + return ops->write_mdata(dev, mdata, primary); > > +} > > + > > /** > > * fwu_get_mdata_part_num() - Get the FWU metadata partition numbers > > * @dev: FWU metadata device > > diff --git a/include/fwu.h b/include/fwu.h > > index 0919ced812..1a700c9e6a 100644 > > --- a/include/fwu.h > > +++ b/include/fwu.h > > @@ -24,6 +24,26 @@ struct fwu_mdata_gpt_blk_priv { > > * @update_mdata() - Update the FWU metadata copy > > */ > > struct fwu_mdata_ops { > > + /** > > + * read_mdata() - Populate the asked FWU metadata copy > > + * @dev: FWU metadata device > > + * @mdata: Copy of the FWU metadata > > + * @primary: If primary or secondary copy of meta-data is to be read > > + * > > + * Return: 0 if OK, -ve on error > > + */ > > + int (*read_mdata)(struct udevice *dev, struct fwu_mdata *mdata, bool primary); > > + > > + /** > > + * write_mdata() - Write the given FWU metadata copy > > + * @dev: FWU metadata device > > + * @mdata: Copy of the FWU metadata > > + * @primary: If primary or secondary copy of meta-data is to be written > > + * > > + * Return: 0 if OK, -ve on error > > + */ > > + int (*write_mdata)(struct udevice *dev, struct fwu_mdata *mdata, bool primary); > > + > > /** > > * check_mdata() - Check if the FWU metadata is valid > > * @dev: FWU device > > @@ -126,6 +146,27 @@ struct fwu_mdata_ops { > > EFI_GUID(0x0c996046, 0xbcc0, 0x4d04, 0x85, 0xec, \ > > 0xe1, 0xfc, 0xed, 0xf1, 0xc6, 0xf8) > > > > +/** > > + * fwu_read_mdata() - Wrapper around fwu_mdata_ops.read_mdata() > > + */ > > +int fwu_read_mdata(struct udevice *dev, struct fwu_mdata *mdata, bool primary); > > + > > +/** > > + * fwu_write_mdata() - Wrapper around fwu_mdata_ops.write_mdata() > > + */ > > +int fwu_write_mdata(struct udevice *dev, struct fwu_mdata *mdata, bool primary); > > + > > +/** > > + * fwu_get_verified_mdata() - Read, verify and return the FWU metadata > > + * > > + * Read both the metadata copies from the storage media, verify their checksum, > > + * and ascertain that both copies match. If one of the copies has gone bad, > > + * restore it from the good copy. > > + * > > + * Return: 0 if OK, -ve on error > > +*/ > > +int fwu_get_verified_mdata(struct fwu_mdata *mdata); > > + > > /** > > * fwu_check_mdata_validity() - Check for validity of the FWU metadata copies > > * > > diff --git a/lib/fwu_updates/fwu.c b/lib/fwu_updates/fwu.c > > index 5313d07302..f17bd8ea63 100644 > > --- a/lib/fwu_updates/fwu.c > > +++ b/lib/fwu_updates/fwu.c > > @@ -15,13 +15,13 @@ > > #include <linux/errno.h> > > #include <linux/types.h> > > > > +#include <u-boot/crc.h> > > + > > +static struct fwu_mdata g_mdata; /* = {0} makes uninit crc32 always invalid */ > > +static struct udevice *g_dev; > > static u8 in_trial; > > static u8 boottime_check; > > > > -#include <linux/errno.h> > > -#include <linux/types.h> > > -#include <u-boot/crc.h> > > - > > enum { > > IMAGE_ACCEPT_SET = 1, > > IMAGE_ACCEPT_CLEAR, > > @@ -161,6 +161,141 @@ static int fwu_get_image_type_id(u8 *image_index, efi_guid_t *image_type_id) > > return -ENOENT; > > } > > > > +/** > > + * fwu_sync_mdata() - Update given meta-data partition(s) with the copy provided > > + * @mdata: FWU metadata structure > > + * @part: Bitmask of FWU metadata partitions to be written to > > + * > > + * Return: 0 if OK, -ve on error > > + */ > > +static int fwu_sync_mdata(struct fwu_mdata *mdata, int part) > > +{ > > + void *buf = &mdata->version; > > + int err = 0; > > + > > + /* > > + * Calculate the crc32 for the updated FWU metadata > > + * and put the updated value in the FWU metadata crc32 > > + * field > > + */ > > + mdata->crc32 = crc32(0, buf, sizeof(*mdata) - sizeof(u32)); > > + > > + if (part & PRIMARY_PART) > > + err = fwu_write_mdata(g_dev, mdata, true); > > + > > + if (err) { > > + log_err("Unable to write primary mdata\n"); > > + return err; > > + } > > + > > + if (part & SECONDARY_PART) > > + err = fwu_write_mdata(g_dev, mdata, false); > > + > > + if (err) { > > + log_err("Unable to write secondary mdata\n"); > > + return err; > > + } > > + > > + /* update the cached copy of meta-data */ > > + memcpy(&g_mdata, mdata, sizeof(struct fwu_mdata)); > > + > > + return 0; > > +} > > + > > +static inline int mdata_crc_check(struct fwu_mdata *mdata) > > +{ > > + void *buf = &mdata->version; > > + u32 calc_crc32 = crc32(0, buf, sizeof(*mdata) - sizeof(u32)); > > + > > + return calc_crc32 == mdata->crc32 ? 0 : -EINVAL; > > +} > > + > > +/** > > + * fwu_get_verified_mdata() - Read, verify and return the FWU metadata > > + * > > + * Read both the metadata copies from the storage media, verify their checksum, > > + * and ascertain that both copies match. If one of the copies has gone bad, > > + * restore it from the good copy. > > + * > > + * Return: 0 if OK, -ve on error > > + */ > > +int fwu_get_verified_mdata(struct fwu_mdata *mdata) > > +{ > > + int err; > > + bool pri_ok, sec_ok; > > + struct fwu_mdata s, *p_mdata, *s_mdata; > > + > > + p_mdata = &g_mdata; > > + s_mdata = &s; > > + > > + /* if mdata already read and ready */ > > + err = mdata_crc_check(p_mdata); > > + if (!err) { > > + if (mdata) > > + memcpy(mdata, p_mdata, sizeof(struct fwu_mdata)); > > + return 0; > > + } > > + /* else read, verify and, if needed, fix mdata */ > > + > > + pri_ok = false; > > + err = fwu_read_mdata(g_dev, p_mdata, true); > > + if (!err) { > > + err = mdata_crc_check(p_mdata); > > + if (!err) > > + pri_ok = true; > > + else > > + log_debug("primary mdata: crc32 failed\n"); > > + } > > + > > + sec_ok = false; > > + err = fwu_read_mdata(g_dev, s_mdata, false); > > + if (!err) { > > + err = mdata_crc_check(s_mdata); > > + if (!err) > > + sec_ok = true; > > + else > > + log_debug("secondary mdata: crc32 failed\n"); > > + } > > + > > + if (pri_ok && sec_ok) { > > + /* > > + * Before returning, check that both the > > + * FWU metadata copies are the same. > > + */ > > + err = memcmp(p_mdata, s_mdata, sizeof(struct fwu_mdata)); > > + if (!err) > > + return 0; > > Copy of the metadata to @mdata is missing here and in success path > before exit_fix branch label. > Thanks for locating the omission. Cheers.
diff --git a/drivers/fwu-mdata/fwu-mdata-uclass.c b/drivers/fwu-mdata/fwu-mdata-uclass.c index b477e9603f..e03773c584 100644 --- a/drivers/fwu-mdata/fwu-mdata-uclass.c +++ b/drivers/fwu-mdata/fwu-mdata-uclass.c @@ -16,6 +16,40 @@ #include <linux/types.h> #include <u-boot/crc.h> +/** + * fwu_read_mdata() - Wrapper around fwu_mdata_ops.read_mdata() + * + * Return: 0 if OK, -ve on error + */ +int fwu_read_mdata(struct udevice *dev, struct fwu_mdata *mdata, bool primary) +{ + const struct fwu_mdata_ops *ops = device_get_ops(dev); + + if (!ops->read_mdata) { + log_debug("read_mdata() method not defined\n"); + return -ENOSYS; + } + + return ops->read_mdata(dev, mdata, primary); +} + +/** + * fwu_write_mdata() - Wrapper around fwu_mdata_ops.write_mdata() + * + * Return: 0 if OK, -ve on error + */ +int fwu_write_mdata(struct udevice *dev, struct fwu_mdata *mdata, bool primary) +{ + const struct fwu_mdata_ops *ops = device_get_ops(dev); + + if (!ops->write_mdata) { + log_debug("write_mdata() method not defined\n"); + return -ENOSYS; + } + + return ops->write_mdata(dev, mdata, primary); +} + /** * fwu_get_mdata_part_num() - Get the FWU metadata partition numbers * @dev: FWU metadata device diff --git a/include/fwu.h b/include/fwu.h index 0919ced812..1a700c9e6a 100644 --- a/include/fwu.h +++ b/include/fwu.h @@ -24,6 +24,26 @@ struct fwu_mdata_gpt_blk_priv { * @update_mdata() - Update the FWU metadata copy */ struct fwu_mdata_ops { + /** + * read_mdata() - Populate the asked FWU metadata copy + * @dev: FWU metadata device + * @mdata: Copy of the FWU metadata + * @primary: If primary or secondary copy of meta-data is to be read + * + * Return: 0 if OK, -ve on error + */ + int (*read_mdata)(struct udevice *dev, struct fwu_mdata *mdata, bool primary); + + /** + * write_mdata() - Write the given FWU metadata copy + * @dev: FWU metadata device + * @mdata: Copy of the FWU metadata + * @primary: If primary or secondary copy of meta-data is to be written + * + * Return: 0 if OK, -ve on error + */ + int (*write_mdata)(struct udevice *dev, struct fwu_mdata *mdata, bool primary); + /** * check_mdata() - Check if the FWU metadata is valid * @dev: FWU device @@ -126,6 +146,27 @@ struct fwu_mdata_ops { EFI_GUID(0x0c996046, 0xbcc0, 0x4d04, 0x85, 0xec, \ 0xe1, 0xfc, 0xed, 0xf1, 0xc6, 0xf8) +/** + * fwu_read_mdata() - Wrapper around fwu_mdata_ops.read_mdata() + */ +int fwu_read_mdata(struct udevice *dev, struct fwu_mdata *mdata, bool primary); + +/** + * fwu_write_mdata() - Wrapper around fwu_mdata_ops.write_mdata() + */ +int fwu_write_mdata(struct udevice *dev, struct fwu_mdata *mdata, bool primary); + +/** + * fwu_get_verified_mdata() - Read, verify and return the FWU metadata + * + * Read both the metadata copies from the storage media, verify their checksum, + * and ascertain that both copies match. If one of the copies has gone bad, + * restore it from the good copy. + * + * Return: 0 if OK, -ve on error +*/ +int fwu_get_verified_mdata(struct fwu_mdata *mdata); + /** * fwu_check_mdata_validity() - Check for validity of the FWU metadata copies * diff --git a/lib/fwu_updates/fwu.c b/lib/fwu_updates/fwu.c index 5313d07302..f17bd8ea63 100644 --- a/lib/fwu_updates/fwu.c +++ b/lib/fwu_updates/fwu.c @@ -15,13 +15,13 @@ #include <linux/errno.h> #include <linux/types.h> +#include <u-boot/crc.h> + +static struct fwu_mdata g_mdata; /* = {0} makes uninit crc32 always invalid */ +static struct udevice *g_dev; static u8 in_trial; static u8 boottime_check; -#include <linux/errno.h> -#include <linux/types.h> -#include <u-boot/crc.h> - enum { IMAGE_ACCEPT_SET = 1, IMAGE_ACCEPT_CLEAR, @@ -161,6 +161,141 @@ static int fwu_get_image_type_id(u8 *image_index, efi_guid_t *image_type_id) return -ENOENT; } +/** + * fwu_sync_mdata() - Update given meta-data partition(s) with the copy provided + * @mdata: FWU metadata structure + * @part: Bitmask of FWU metadata partitions to be written to + * + * Return: 0 if OK, -ve on error + */ +static int fwu_sync_mdata(struct fwu_mdata *mdata, int part) +{ + void *buf = &mdata->version; + int err = 0; + + /* + * Calculate the crc32 for the updated FWU metadata + * and put the updated value in the FWU metadata crc32 + * field + */ + mdata->crc32 = crc32(0, buf, sizeof(*mdata) - sizeof(u32)); + + if (part & PRIMARY_PART) + err = fwu_write_mdata(g_dev, mdata, true); + + if (err) { + log_err("Unable to write primary mdata\n"); + return err; + } + + if (part & SECONDARY_PART) + err = fwu_write_mdata(g_dev, mdata, false); + + if (err) { + log_err("Unable to write secondary mdata\n"); + return err; + } + + /* update the cached copy of meta-data */ + memcpy(&g_mdata, mdata, sizeof(struct fwu_mdata)); + + return 0; +} + +static inline int mdata_crc_check(struct fwu_mdata *mdata) +{ + void *buf = &mdata->version; + u32 calc_crc32 = crc32(0, buf, sizeof(*mdata) - sizeof(u32)); + + return calc_crc32 == mdata->crc32 ? 0 : -EINVAL; +} + +/** + * fwu_get_verified_mdata() - Read, verify and return the FWU metadata + * + * Read both the metadata copies from the storage media, verify their checksum, + * and ascertain that both copies match. If one of the copies has gone bad, + * restore it from the good copy. + * + * Return: 0 if OK, -ve on error + */ +int fwu_get_verified_mdata(struct fwu_mdata *mdata) +{ + int err; + bool pri_ok, sec_ok; + struct fwu_mdata s, *p_mdata, *s_mdata; + + p_mdata = &g_mdata; + s_mdata = &s; + + /* if mdata already read and ready */ + err = mdata_crc_check(p_mdata); + if (!err) { + if (mdata) + memcpy(mdata, p_mdata, sizeof(struct fwu_mdata)); + return 0; + } + /* else read, verify and, if needed, fix mdata */ + + pri_ok = false; + err = fwu_read_mdata(g_dev, p_mdata, true); + if (!err) { + err = mdata_crc_check(p_mdata); + if (!err) + pri_ok = true; + else + log_debug("primary mdata: crc32 failed\n"); + } + + sec_ok = false; + err = fwu_read_mdata(g_dev, s_mdata, false); + if (!err) { + err = mdata_crc_check(s_mdata); + if (!err) + sec_ok = true; + else + log_debug("secondary mdata: crc32 failed\n"); + } + + if (pri_ok && sec_ok) { + /* + * Before returning, check that both the + * FWU metadata copies are the same. + */ + err = memcmp(p_mdata, s_mdata, sizeof(struct fwu_mdata)); + if (!err) + return 0; + + /* + * If not, populate the secondary partition from the + * primary partition copy. + */ + log_info("Both FWU metadata copies are valid but do not match."); + log_info(" Restoring the secondary partition from the primary\n"); + sec_ok = false; + } + + if (!pri_ok) { + memcpy(p_mdata, s_mdata, sizeof(struct fwu_mdata)); + err = fwu_sync_mdata(p_mdata, PRIMARY_PART); + if (err) + goto exit_fix; + } + + if (!sec_ok) { + memcpy(s_mdata, p_mdata, sizeof(struct fwu_mdata)); + err = fwu_sync_mdata(s_mdata, SECONDARY_PART); + if (err) + goto exit_fix; + } + +exit_fix: + if (err) + log_debug("mdata saving : crc32 failed\n"); + + return err; +} + /** * fwu_verify_mdata() - Verify the FWU metadata * @mdata: FWU metadata structure