[PATCH v6 03/12] tpm-buf: add cursor based functions for response parsing
From: James Bottomley <James.Bottomley@HansenPartnership.com>
Date: 2019-09-09 12:19:22
Also in:
linux-crypto, linux-integrity
Subsystem:
the rest, tpm device driver · Maintainers:
Linus Torvalds, Peter Huewe, Jarkko Sakkinen
It's very convenient when parsing responses to have a cursor you simply move over the response extracting the data. Add such cursor functions for the TPM unsigned integer types. Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com> --- drivers/char/tpm/tpm-buf.c | 26 ++++++++++++++++++++++++++ drivers/char/tpm/tpm.h | 4 ++++ 2 files changed, 30 insertions(+)
diff --git a/drivers/char/tpm/tpm-buf.c b/drivers/char/tpm/tpm-buf.c
index 8c1ed8a14e01..553adb84b0ac 100644
--- a/drivers/char/tpm/tpm-buf.c
+++ b/drivers/char/tpm/tpm-buf.c@@ -163,3 +163,29 @@ void tpm_buf_append_2b(struct tpm_buf *buf, struct tpm_buf *tpm2b) } EXPORT_SYMBOL_GPL(tpm_buf_append_2b); +/* functions for unmarshalling data and moving the cursor */ +u8 tpm_get_inc_u8(const u8 **ptr) +{ + return *((*ptr)++); +} +EXPORT_SYMBOL_GPL(tpm_get_inc_u8); + +u16 tpm_get_inc_u16(const u8 **ptr) +{ + u16 val; + + val = get_unaligned_be16(*ptr); + *ptr += sizeof(val); + return val; +} +EXPORT_SYMBOL_GPL(tpm_get_inc_u16); + +u32 tpm_get_inc_u32(const u8 **ptr) +{ + u32 val; + + val = get_unaligned_be32(*ptr); + *ptr += sizeof(val); + return val; +} +EXPORT_SYMBOL_GPL(tpm_get_inc_u32);
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 7627917db345..d942188debc9 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h@@ -302,6 +302,10 @@ void tpm_buf_append_u16(struct tpm_buf *buf, const u16 value); void tpm_buf_append_u32(struct tpm_buf *buf, const u32 value); void tpm_buf_append_2b(struct tpm_buf *buf, struct tpm_buf *tpm2b); +u8 tpm_get_inc_u8(const u8 **ptr); +u16 tpm_get_inc_u16(const u8 **ptr); +u32 tpm_get_inc_u32(const u8 **ptr); + extern struct class *tpm_class; extern struct class *tpmrm_class; extern dev_t tpm_devt;
--
2.16.4