SHA1 and SHA256 are hard-coded here, but their support by the TPM is
checked. Addition of event log for TPM2.0 will generalize the code
further.
Signed-off-by: Sergii Dmytruk <sergii.dmytruk@3mdeb.com>
---
xen/arch/x86/tpm.c | 464 +++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 452 insertions(+), 12 deletions(-)
diff --git a/xen/arch/x86/tpm.c b/xen/arch/x86/tpm.c
index 7fb19ce4fa..ed49fe3ccf 100644
--- a/xen/arch/x86/tpm.c
+++ b/xen/arch/x86/tpm.c
@@ -5,6 +5,7 @@
*/
#include <xen/sha1.h>
+#include <xen/sha2.h>
#include <xen/string.h>
#include <xen/types.h>
#include <asm/intel-txt.h>
@@ -31,6 +32,15 @@ struct slr_table *slaunch_get_slrt(void)
* other part of Xen. Providing implementation of builtin functions in this
* case is necessary if compiler chooses to not use an inline builtin.
*/
+void *(memset)(void *s, int c, size_t n)
+{
+ uint8_t *d = s;
+
+ while ( n-- )
+ *d++ = c;
+
+ return s;
+}
void *(memcpy)(void *dest, const void *src, size_t n)
{
const uint8_t *s = src;
@@ -146,14 +156,15 @@ static inline bool is_tpm12(void)
(tis_read32(TPM_STS_(0)) & TPM_FAMILY_MASK) == 0);
}
-/****************************** TPM1.2 specific *******************************/
-#define TPM_ORD_Extend 0x00000014
-#define TPM_ORD_SHA1Start 0x000000A0
-#define TPM_ORD_SHA1Update 0x000000A1
-#define TPM_ORD_SHA1CompleteExtend 0x000000A3
+/****************************** TPM1.2 & TPM2.0 *******************************/
-#define TPM_TAG_RQU_COMMAND 0x00C1
-#define TPM_TAG_RSP_COMMAND 0x00C4
+/*
+ * TPM1.2 is required to support commands of up to 1101 bytes, vendors rarely
+ * go above that. Limit maximum size of block of data to be hashed to 1024.
+ *
+ * TPM2.0 should support hashing of at least 1024 bytes.
+ */
+#define MAX_HASH_BLOCK 1024
/* All fields of following structs are big endian. */
struct tpm_cmd_hdr {
@@ -168,6 +179,17 @@ struct tpm_rsp_hdr {
uint32_t returnCode;
} __packed;
+/****************************** TPM1.2 specific *******************************/
+
+#define TPM_ORD_Extend 0x00000014
+#define TPM_ORD_SHA1Start 0x000000A0
+#define TPM_ORD_SHA1Update 0x000000A1
+#define TPM_ORD_SHA1CompleteExtend 0x000000A3
+
+#define TPM_TAG_RQU_COMMAND 0x00C1
+#define TPM_TAG_RSP_COMMAND 0x00C4
+
+/* All fields of following structs are big endian. */
struct extend_cmd {
struct tpm_cmd_hdr h;
uint32_t pcrNum;
@@ -233,11 +255,6 @@ struct txt_ev_log_container_12 {
};
#ifdef __EARLY_SLAUNCH__
-/*
- * TPM1.2 is required to support commands of up to 1101 bytes, vendors rarely
- * go above that. Limit maximum size of block of data to be hashed to 1024.
- */
-#define MAX_HASH_BLOCK 1024
#define CMD_RSP_BUF_SIZE (sizeof(struct sha1_update_cmd) + MAX_HASH_BLOCK)
union cmd_rsp {
@@ -393,6 +410,400 @@ static void *create_log_event12(struct txt_ev_log_container_12 *evt_log,
/************************** end of TPM1.2 specific ****************************/
+/****************************** TPM2.0 specific *******************************/
+
+/*
+ * These constants are for TPM2.0 but don't have a distinct prefix to match
+ * names in the specification.
+ */
+
+#define TPM_HT_PCR 0x00
+
+#define TPM_RH_NULL 0x40000007
+#define TPM_RS_PW 0x40000009
+
+#define HR_SHIFT 24
+#define HR_PCR (TPM_HT_PCR << HR_SHIFT)
+
+#define TPM_ST_NO_SESSIONS 0x8001
+#define TPM_ST_SESSIONS 0x8002
+
+#define TPM_ALG_SHA1 0x0004
+#define TPM_ALG_SHA256 0x000b
+#define TPM_ALG_NULL 0x0010
+
+#define TPM2_PCR_Extend 0x00000182
+#define TPM2_PCR_HashSequenceStart 0x00000186
+#define TPM2_PCR_SequenceUpdate 0x0000015C
+#define TPM2_PCR_EventSequenceComplete 0x00000185
+
+#define PUT_BYTES(p, bytes, size) do { \
+ memcpy((p), (bytes), (size)); \
+ (p) += (size); \
+ } while ( 0 )
+
+#define PUT_16BIT(p, data) do { \
+ *(uint16_t *)(p) = swap16(data); \
+ (p) += 2; \
+ } while ( 0 )
+
+/* All fields of following structs are big endian. */
+struct tpm2_session_header {
+ uint32_t handle;
+ uint16_t nonceSize;
+ uint8_t nonce[0];
+ uint8_t attrs;
+ uint16_t hmacSize;
+ uint8_t hmac[0];
+} __packed;
+
+struct tpm2_extend_cmd {
+ struct tpm_cmd_hdr h;
+ uint32_t pcrHandle;
+ uint32_t sessionHdrSize;
+ struct tpm2_session_header pcrSession;
+ uint32_t hashCount;
+ uint8_t hashes[0];
+} __packed;
+
+struct tpm2_extend_rsp {
+ struct tpm_rsp_hdr h;
+} __packed;
+
+struct tpm2_sequence_start_cmd {
+ struct tpm_cmd_hdr h;
+ uint16_t hmacSize;
+ uint8_t hmac[0];
+ uint16_t hashAlg;
+} __packed;
+
+struct tpm2_sequence_start_rsp {
+ struct tpm_rsp_hdr h;
+ uint32_t sequenceHandle;
+} __packed;
+
+struct tpm2_sequence_update_cmd {
+ struct tpm_cmd_hdr h;
+ uint32_t sequenceHandle;
+ uint32_t sessionHdrSize;
+ struct tpm2_session_header session;
+ uint16_t dataSize;
+ uint8_t data[0];
+} __packed;
+
+struct tpm2_sequence_update_rsp {
+ struct tpm_rsp_hdr h;
+} __packed;
+
+struct tpm2_sequence_complete_cmd {
+ struct tpm_cmd_hdr h;
+ uint32_t pcrHandle;
+ uint32_t sequenceHandle;
+ uint32_t sessionHdrSize;
+ struct tpm2_session_header pcrSession;
+ struct tpm2_session_header sequenceSession;
+ uint16_t dataSize;
+ uint8_t data[0];
+} __packed;
+
+struct tpm2_sequence_complete_rsp {
+ struct tpm_rsp_hdr h;
+ uint32_t paramSize;
+ uint32_t hashCount;
+ uint8_t hashes[0];
+ /*
+ * Each hash is represented as:
+ * struct {
+ * uint16_t hashAlg;
+ * uint8_t hash[size of hashAlg];
+ * };
+ */
+} __packed;
+
+/*
+ * These two structure are for convenience, they don't correspond to anything in
+ * any spec.
+ */
+struct tpm2_log_hash {
+ uint16_t alg; /* TPM_ALG_* */
+ uint16_t size;
+ uint8_t *data; /* Non-owning reference to a buffer inside log entry. */
+};
+/* Should be more than enough for now and awhile in the future. */
+#define MAX_HASH_COUNT 8
+struct tpm2_log_hashes {
+ uint32_t count;
+ struct tpm2_log_hash hashes[MAX_HASH_COUNT];
+};
+
+#ifdef __EARLY_SLAUNCH__
+
+union tpm2_cmd_rsp {
+ uint8_t b[sizeof(struct tpm2_sequence_update_cmd) + MAX_HASH_BLOCK];
+ struct tpm_cmd_hdr c;
+ struct tpm_rsp_hdr r;
+ struct tpm2_sequence_start_cmd start_c;
+ struct tpm2_sequence_start_rsp start_r;
+ struct tpm2_sequence_update_cmd update_c;
+ struct tpm2_sequence_update_rsp update_r;
+ struct tpm2_sequence_complete_cmd finish_c;
+ struct tpm2_sequence_complete_rsp finish_r;
+};
+
+static uint32_t tpm2_hash_extend(unsigned loc, const uint8_t *buf,
+ unsigned size, unsigned pcr,
+ struct tpm2_log_hashes *log_hashes)
+{
+ uint32_t seq_handle;
+ unsigned max_bytes = MAX_HASH_BLOCK;
+
+ union tpm2_cmd_rsp cmd_rsp;
+ unsigned o_size;
+ unsigned i;
+ uint8_t *p;
+ uint32_t rc;
+
+ cmd_rsp.start_c = (struct tpm2_sequence_start_cmd) {
+ .h.tag = swap16(TPM_ST_NO_SESSIONS),
+ .h.paramSize = swap32(sizeof(cmd_rsp.start_c)),
+ .h.ordinal = swap32(TPM2_PCR_HashSequenceStart),
+ .hashAlg = swap16(TPM_ALG_NULL), /* Compute all supported hashes. */
+ };
+
+ request_locality(loc);
+
+ o_size = sizeof(cmd_rsp);
+ send_cmd(loc, cmd_rsp.b, swap32(cmd_rsp.c.paramSize), &o_size);
+
+ if ( cmd_rsp.r.tag == swap16(TPM_ST_NO_SESSIONS) &&
+ cmd_rsp.r.paramSize == swap32(10) )
+ {
+ rc = swap32(cmd_rsp.r.returnCode);
+ if ( rc != 0 )
+ goto error;
+ }
+
+ seq_handle = swap32(cmd_rsp.start_r.sequenceHandle);
+
+ while ( size > 64 )
+ {
+ if ( size < max_bytes )
+ max_bytes = size & ~(64 - 1);
+
+ cmd_rsp.update_c = (struct tpm2_sequence_update_cmd) {
+ .h.tag = swap16(TPM_ST_SESSIONS),
+ .h.paramSize = swap32(sizeof(cmd_rsp.update_c) + max_bytes),
+ .h.ordinal = swap32(TPM2_PCR_SequenceUpdate),
+ .sequenceHandle = swap32(seq_handle),
+ .sessionHdrSize = swap32(sizeof(struct tpm2_session_header)),
+ .session.handle = swap32(TPM_RS_PW),
+ .dataSize = swap16(max_bytes),
+ };
+
+ memcpy(cmd_rsp.update_c.data, buf, max_bytes);
+
+ o_size = sizeof(cmd_rsp);
+ send_cmd(loc, cmd_rsp.b, swap32(cmd_rsp.c.paramSize), &o_size);
+
+ if ( cmd_rsp.r.tag == swap16(TPM_ST_NO_SESSIONS) &&
+ cmd_rsp.r.paramSize == swap32(10) )
+ {
+ rc = swap32(cmd_rsp.r.returnCode);
+ if ( rc != 0 )
+ goto error;
+ }
+
+ size -= max_bytes;
+ buf += max_bytes;
+ }
+
+ cmd_rsp.finish_c = (struct tpm2_sequence_complete_cmd) {
+ .h.tag = swap16(TPM_ST_SESSIONS),
+ .h.paramSize = swap32(sizeof(cmd_rsp.finish_c) + size),
+ .h.ordinal = swap32(TPM2_PCR_EventSequenceComplete),
+ .pcrHandle = swap32(HR_PCR + pcr),
+ .sequenceHandle = swap32(seq_handle),
+ .sessionHdrSize = swap32(sizeof(struct tpm2_session_header)*2),
+ .pcrSession.handle = swap32(TPM_RS_PW),
+ .sequenceSession.handle = swap32(TPM_RS_PW),
+ .dataSize = swap16(size),
+ };
+
+ memcpy(cmd_rsp.finish_c.data, buf, size);
+
+ o_size = sizeof(cmd_rsp);
+ send_cmd(loc, cmd_rsp.b, swap32(cmd_rsp.c.paramSize), &o_size);
+
+ if ( cmd_rsp.r.tag == swap16(TPM_ST_NO_SESSIONS) &&
+ cmd_rsp.r.paramSize == swap32(10) )
+ {
+ rc = swap32(cmd_rsp.r.returnCode);
+ if ( rc != 0 )
+ goto error;
+ }
+
+ p = cmd_rsp.finish_r.hashes;
+ for ( i = 0; i < swap32(cmd_rsp.finish_r.hashCount); ++i )
+ {
+ unsigned j;
+ uint16_t hash_type;
+
+ hash_type = swap16(*(uint16_t *)p);
+ p += sizeof(uint16_t);
+
+ for ( j = 0; j < log_hashes->count; ++j )
+ {
+ struct tpm2_log_hash *hash = &log_hashes->hashes[j];
+ if ( hash->alg == hash_type )
+ {
+ memcpy(hash->data, p, hash->size);
+ p += hash->size;
+ break;
+ }
+ }
+
+ if ( j == log_hashes->count )
+ /* Can't continue parsing without knowing hash size. */
+ break;
+ }
+
+ rc = 0;
+
+error:
+ relinquish_locality(loc);
+ return rc;
+}
+
+#else
+
+union tpm2_cmd_rsp {
+ /* Enough space for multiple hashes. */
+ uint8_t b[sizeof(struct tpm2_extend_cmd) + 1024];
+ struct tpm_cmd_hdr c;
+ struct tpm_rsp_hdr r;
+ struct tpm2_extend_cmd extend_c;
+ struct tpm2_extend_rsp extend_r;
+};
+
+static uint32_t tpm20_pcr_extend(unsigned loc, uint32_t pcr_handle,
+ const struct tpm2_log_hashes *log_hashes)
+{
+ union tpm2_cmd_rsp cmd_rsp;
+ unsigned o_size;
+ unsigned i;
+ uint8_t *p;
+
+ cmd_rsp.extend_c = (struct tpm2_extend_cmd) {
+ .h.tag = swap16(TPM_ST_SESSIONS),
+ .h.ordinal = swap32(TPM2_PCR_Extend),
+ .pcrHandle = swap32(pcr_handle),
+ .sessionHdrSize = swap32(sizeof(struct tpm2_session_header)),
+ .pcrSession.handle = swap32(TPM_RS_PW),
+ .hashCount = swap32(log_hashes->count),
+ };
+
+ p = cmd_rsp.extend_c.hashes;
+ for ( i = 0; i < log_hashes->count; ++i )
+ {
+ const struct tpm2_log_hash *hash = &log_hashes->hashes[i];
+
+ if ( p + sizeof(uint16_t) + hash->size > &cmd_rsp.b[sizeof(cmd_rsp)] )
+ {
+ printk(XENLOG_ERR "Hit TPM message size implementation limit: %ld\n",
+ sizeof(cmd_rsp));
+ return -1;
+ }
+
+ *(uint16_t *)p = swap16(hash->alg);
+ p += sizeof(uint16_t);
+
+ memcpy(p, hash->data, hash->size);
+ p += hash->size;
+ }
+
+ /* Fill in command size (size of the whole buffer). */
+ cmd_rsp.extend_c.h.paramSize = swap32(sizeof(cmd_rsp.extend_c) +
+ (p - cmd_rsp.extend_c.hashes)),
+
+ o_size = sizeof(cmd_rsp);
+ send_cmd(loc, cmd_rsp.b, swap32(cmd_rsp.c.paramSize), &o_size);
+
+ return swap32(cmd_rsp.r.returnCode);
+}
+
+static bool tpm_supports_hash(unsigned loc, const struct tpm2_log_hash *hash)
+{
+ uint32_t rc;
+ struct tpm2_log_hashes hashes = {
+ .count = 1,
+ .hashes[0] = *hash,
+ };
+
+ /*
+ * This is a valid way of checking hash support, using it to not implement
+ * TPM2_GetCapability().
+ */
+ rc = tpm20_pcr_extend(loc, /*pcr_handle=*/TPM_RH_NULL, &hashes);
+
+ return rc == 0;
+}
+
+static uint32_t tpm2_hash_extend(unsigned loc, const uint8_t *buf,
+ unsigned size, unsigned pcr,
+ const struct tpm2_log_hashes *log_hashes)
+{
+ uint32_t rc;
+ unsigned i;
+ struct tpm2_log_hashes supported_hashes = {0};
+
+ request_locality(loc);
+
+ for ( i = 0; i < log_hashes->count; ++i )
+ {
+ const struct tpm2_log_hash *hash = &log_hashes->hashes[i];
+ if ( !tpm_supports_hash(loc, hash) )
+ {
+ printk(XENLOG_WARNING "Skipped hash unsupported by TPM: %d\n",
+ hash->alg);
+ continue;
+ }
+
+ if ( hash->alg == TPM_ALG_SHA1 )
+ {
+ sha1_hash(hash->data, buf, size);
+ }
+ else if ( hash->alg == TPM_ALG_SHA256 )
+ {
+ sha2_256_digest(hash->data, buf, size);
+ }
+ else
+ {
+ /* This is called "OneDigest" in TXT Software Development Guide. */
+ memset(hash->data, 0, size);
+ hash->data[0] = 1;
+ }
+
+ if ( supported_hashes.count == MAX_HASH_COUNT )
+ {
+ printk(XENLOG_ERR "Hit hash count implementation limit: %d\n",
+ MAX_HASH_COUNT);
+ return -1;
+ }
+
+ supported_hashes.hashes[supported_hashes.count] = *hash;
+ ++supported_hashes.count;
+ }
+
+ rc = tpm20_pcr_extend(loc, HR_PCR + pcr, &supported_hashes);
+ relinquish_locality(loc);
+
+ return rc;
+}
+
+#endif /* __EARLY_SLAUNCH__ */
+
+/************************** end of TPM2.0 specific ****************************/
+
void tpm_hash_extend(unsigned loc, unsigned pcr, const uint8_t *buf,
unsigned size, uint32_t type, const uint8_t *log_data,
unsigned log_data_size)
@@ -419,6 +830,35 @@ void tpm_hash_extend(unsigned loc, unsigned pcr, const uint8_t *buf,
{
#ifndef __EARLY_SLAUNCH__
printk(XENLOG_ERR "Extending PCR%u failed\n", pcr);
+#endif
+ }
+ } else {
+ uint8_t sha1_digest[SHA1_DIGEST_SIZE];
+ uint8_t sha256_digest[SHA2_256_DIGEST_SIZE];
+ uint32_t rc;
+
+ struct tpm2_log_hashes log_hashes = {
+ .count = 2,
+ .hashes = {
+ {
+ .alg = TPM_ALG_SHA1,
+ .size = SHA1_DIGEST_SIZE,
+ .data = sha1_digest,
+ },
+ {
+ .alg = TPM_ALG_SHA256,
+ .size = SHA2_256_DIGEST_SIZE,
+ .data = sha256_digest,
+ },
+ },
+ };
+
+ rc = tpm2_hash_extend(loc, buf, size, pcr, &log_hashes);
+ if ( rc != 0 )
+ {
+#ifndef __EARLY_SLAUNCH__
+ printk(XENLOG_ERR "Extending PCR%u failed with TPM error: 0x%08x\n",
+ pcr, rc);
#endif
}
}
--
2.49.0On 30.05.2025 15:17, Sergii Dmytruk wrote:
> @@ -146,14 +156,15 @@ static inline bool is_tpm12(void)
> (tis_read32(TPM_STS_(0)) & TPM_FAMILY_MASK) == 0);
> }
>
> -/****************************** TPM1.2 specific *******************************/
> -#define TPM_ORD_Extend 0x00000014
> -#define TPM_ORD_SHA1Start 0x000000A0
> -#define TPM_ORD_SHA1Update 0x000000A1
> -#define TPM_ORD_SHA1CompleteExtend 0x000000A3
> +/****************************** TPM1.2 & TPM2.0 *******************************/
>
> -#define TPM_TAG_RQU_COMMAND 0x00C1
> -#define TPM_TAG_RSP_COMMAND 0x00C4
> +/*
> + * TPM1.2 is required to support commands of up to 1101 bytes, vendors rarely
> + * go above that. Limit maximum size of block of data to be hashed to 1024.
> + *
> + * TPM2.0 should support hashing of at least 1024 bytes.
> + */
> +#define MAX_HASH_BLOCK 1024
>
> /* All fields of following structs are big endian. */
> struct tpm_cmd_hdr {
> @@ -168,6 +179,17 @@ struct tpm_rsp_hdr {
> uint32_t returnCode;
> } __packed;
>
> +/****************************** TPM1.2 specific *******************************/
> +
> +#define TPM_ORD_Extend 0x00000014
> +#define TPM_ORD_SHA1Start 0x000000A0
> +#define TPM_ORD_SHA1Update 0x000000A1
> +#define TPM_ORD_SHA1CompleteExtend 0x000000A3
> +
> +#define TPM_TAG_RQU_COMMAND 0x00C1
> +#define TPM_TAG_RSP_COMMAND 0x00C4
> +
> +/* All fields of following structs are big endian. */
> struct extend_cmd {
> struct tpm_cmd_hdr h;
> uint32_t pcrNum;
Can the previous patch please put these right in their final resting place?
> @@ -233,11 +255,6 @@ struct txt_ev_log_container_12 {
> };
>
> #ifdef __EARLY_SLAUNCH__
> -/*
> - * TPM1.2 is required to support commands of up to 1101 bytes, vendors rarely
> - * go above that. Limit maximum size of block of data to be hashed to 1024.
> - */
> -#define MAX_HASH_BLOCK 1024
> #define CMD_RSP_BUF_SIZE (sizeof(struct sha1_update_cmd) + MAX_HASH_BLOCK)
>
> union cmd_rsp {
> @@ -393,6 +410,400 @@ static void *create_log_event12(struct txt_ev_log_container_12 *evt_log,
>
> /************************** end of TPM1.2 specific ****************************/
>
> +/****************************** TPM2.0 specific *******************************/
> +
> +/*
> + * These constants are for TPM2.0 but don't have a distinct prefix to match
> + * names in the specification.
> + */
> +
> +#define TPM_HT_PCR 0x00
> +
> +#define TPM_RH_NULL 0x40000007
> +#define TPM_RS_PW 0x40000009
> +
> +#define HR_SHIFT 24
> +#define HR_PCR (TPM_HT_PCR << HR_SHIFT)
> +
> +#define TPM_ST_NO_SESSIONS 0x8001
> +#define TPM_ST_SESSIONS 0x8002
> +
> +#define TPM_ALG_SHA1 0x0004
> +#define TPM_ALG_SHA256 0x000b
> +#define TPM_ALG_NULL 0x0010
> +
> +#define TPM2_PCR_Extend 0x00000182
> +#define TPM2_PCR_HashSequenceStart 0x00000186
> +#define TPM2_PCR_SequenceUpdate 0x0000015C
> +#define TPM2_PCR_EventSequenceComplete 0x00000185
> +
> +#define PUT_BYTES(p, bytes, size) do { \
> + memcpy((p), (bytes), (size)); \
Preferably without the excess parentheses, much like you have it ...
> + (p) += (size); \
> + } while ( 0 )
> +
> +#define PUT_16BIT(p, data) do { \
> + *(uint16_t *)(p) = swap16(data); \
... e.g. in the function call here.
> + (p) += 2; \
> + } while ( 0 )
> +
> +/* All fields of following structs are big endian. */
> +struct tpm2_session_header {
> + uint32_t handle;
> + uint16_t nonceSize;
> + uint8_t nonce[0];
> + uint8_t attrs;
> + uint16_t hmacSize;
> + uint8_t hmac[0];
> +} __packed;
> +
> +struct tpm2_extend_cmd {
> + struct tpm_cmd_hdr h;
> + uint32_t pcrHandle;
> + uint32_t sessionHdrSize;
> + struct tpm2_session_header pcrSession;
> + uint32_t hashCount;
> + uint8_t hashes[0];
> +} __packed;
> +
> +struct tpm2_extend_rsp {
> + struct tpm_rsp_hdr h;
> +} __packed;
> +
> +struct tpm2_sequence_start_cmd {
> + struct tpm_cmd_hdr h;
> + uint16_t hmacSize;
> + uint8_t hmac[0];
> + uint16_t hashAlg;
> +} __packed;
> +
> +struct tpm2_sequence_start_rsp {
> + struct tpm_rsp_hdr h;
> + uint32_t sequenceHandle;
> +} __packed;
> +
> +struct tpm2_sequence_update_cmd {
> + struct tpm_cmd_hdr h;
> + uint32_t sequenceHandle;
> + uint32_t sessionHdrSize;
> + struct tpm2_session_header session;
> + uint16_t dataSize;
> + uint8_t data[0];
> +} __packed;
> +
> +struct tpm2_sequence_update_rsp {
> + struct tpm_rsp_hdr h;
> +} __packed;
> +
> +struct tpm2_sequence_complete_cmd {
> + struct tpm_cmd_hdr h;
> + uint32_t pcrHandle;
> + uint32_t sequenceHandle;
> + uint32_t sessionHdrSize;
> + struct tpm2_session_header pcrSession;
> + struct tpm2_session_header sequenceSession;
> + uint16_t dataSize;
> + uint8_t data[0];
> +} __packed;
> +
> +struct tpm2_sequence_complete_rsp {
> + struct tpm_rsp_hdr h;
> + uint32_t paramSize;
> + uint32_t hashCount;
> + uint8_t hashes[0];
> + /*
> + * Each hash is represented as:
> + * struct {
> + * uint16_t hashAlg;
> + * uint8_t hash[size of hashAlg];
> + * };
> + */
> +} __packed;
> +
> +/*
> + * These two structure are for convenience, they don't correspond to anything in
> + * any spec.
> + */
> +struct tpm2_log_hash {
> + uint16_t alg; /* TPM_ALG_* */
> + uint16_t size;
> + uint8_t *data; /* Non-owning reference to a buffer inside log entry. */
> +};
> +/* Should be more than enough for now and awhile in the future. */
> +#define MAX_HASH_COUNT 8
> +struct tpm2_log_hashes {
> + uint32_t count;
> + struct tpm2_log_hash hashes[MAX_HASH_COUNT];
> +};
> +
> +#ifdef __EARLY_SLAUNCH__
> +
> +union tpm2_cmd_rsp {
> + uint8_t b[sizeof(struct tpm2_sequence_update_cmd) + MAX_HASH_BLOCK];
> + struct tpm_cmd_hdr c;
> + struct tpm_rsp_hdr r;
> + struct tpm2_sequence_start_cmd start_c;
> + struct tpm2_sequence_start_rsp start_r;
> + struct tpm2_sequence_update_cmd update_c;
> + struct tpm2_sequence_update_rsp update_r;
> + struct tpm2_sequence_complete_cmd finish_c;
> + struct tpm2_sequence_complete_rsp finish_r;
> +};
> +
> +static uint32_t tpm2_hash_extend(unsigned loc, const uint8_t *buf,
> + unsigned size, unsigned pcr,
> + struct tpm2_log_hashes *log_hashes)
> +{
> + uint32_t seq_handle;
> + unsigned max_bytes = MAX_HASH_BLOCK;
> +
> + union tpm2_cmd_rsp cmd_rsp;
> + unsigned o_size;
> + unsigned i;
> + uint8_t *p;
> + uint32_t rc;
> +
> + cmd_rsp.start_c = (struct tpm2_sequence_start_cmd) {
> + .h.tag = swap16(TPM_ST_NO_SESSIONS),
> + .h.paramSize = swap32(sizeof(cmd_rsp.start_c)),
> + .h.ordinal = swap32(TPM2_PCR_HashSequenceStart),
> + .hashAlg = swap16(TPM_ALG_NULL), /* Compute all supported hashes. */
> + };
> +
> + request_locality(loc);
> +
> + o_size = sizeof(cmd_rsp);
> + send_cmd(loc, cmd_rsp.b, swap32(cmd_rsp.c.paramSize), &o_size);
> +
> + if ( cmd_rsp.r.tag == swap16(TPM_ST_NO_SESSIONS) &&
> + cmd_rsp.r.paramSize == swap32(10) )
> + {
> + rc = swap32(cmd_rsp.r.returnCode);
> + if ( rc != 0 )
> + goto error;
> + }
> +
> + seq_handle = swap32(cmd_rsp.start_r.sequenceHandle);
> +
> + while ( size > 64 )
> + {
> + if ( size < max_bytes )
> + max_bytes = size & ~(64 - 1);
> +
> + cmd_rsp.update_c = (struct tpm2_sequence_update_cmd) {
> + .h.tag = swap16(TPM_ST_SESSIONS),
> + .h.paramSize = swap32(sizeof(cmd_rsp.update_c) + max_bytes),
> + .h.ordinal = swap32(TPM2_PCR_SequenceUpdate),
> + .sequenceHandle = swap32(seq_handle),
> + .sessionHdrSize = swap32(sizeof(struct tpm2_session_header)),
> + .session.handle = swap32(TPM_RS_PW),
> + .dataSize = swap16(max_bytes),
> + };
> +
> + memcpy(cmd_rsp.update_c.data, buf, max_bytes);
> +
> + o_size = sizeof(cmd_rsp);
> + send_cmd(loc, cmd_rsp.b, swap32(cmd_rsp.c.paramSize), &o_size);
> +
> + if ( cmd_rsp.r.tag == swap16(TPM_ST_NO_SESSIONS) &&
> + cmd_rsp.r.paramSize == swap32(10) )
> + {
> + rc = swap32(cmd_rsp.r.returnCode);
> + if ( rc != 0 )
> + goto error;
> + }
> +
> + size -= max_bytes;
> + buf += max_bytes;
> + }
> +
> + cmd_rsp.finish_c = (struct tpm2_sequence_complete_cmd) {
> + .h.tag = swap16(TPM_ST_SESSIONS),
> + .h.paramSize = swap32(sizeof(cmd_rsp.finish_c) + size),
> + .h.ordinal = swap32(TPM2_PCR_EventSequenceComplete),
> + .pcrHandle = swap32(HR_PCR + pcr),
> + .sequenceHandle = swap32(seq_handle),
> + .sessionHdrSize = swap32(sizeof(struct tpm2_session_header)*2),
Why *2? Where to the two session headers go? (Also nit: blanks missing around *.)
> + .pcrSession.handle = swap32(TPM_RS_PW),
> + .sequenceSession.handle = swap32(TPM_RS_PW),
> + .dataSize = swap16(size),
> + };
> +
> + memcpy(cmd_rsp.finish_c.data, buf, size);
> +
> + o_size = sizeof(cmd_rsp);
> + send_cmd(loc, cmd_rsp.b, swap32(cmd_rsp.c.paramSize), &o_size);
> +
> + if ( cmd_rsp.r.tag == swap16(TPM_ST_NO_SESSIONS) &&
> + cmd_rsp.r.paramSize == swap32(10) )
> + {
> + rc = swap32(cmd_rsp.r.returnCode);
> + if ( rc != 0 )
> + goto error;
> + }
> +
> + p = cmd_rsp.finish_r.hashes;
> + for ( i = 0; i < swap32(cmd_rsp.finish_r.hashCount); ++i )
> + {
> + unsigned j;
> + uint16_t hash_type;
> +
> + hash_type = swap16(*(uint16_t *)p);
> + p += sizeof(uint16_t);
> +
> + for ( j = 0; j < log_hashes->count; ++j )
> + {
> + struct tpm2_log_hash *hash = &log_hashes->hashes[j];
> + if ( hash->alg == hash_type )
> + {
> + memcpy(hash->data, p, hash->size);
> + p += hash->size;
> + break;
> + }
> + }
> +
> + if ( j == log_hashes->count )
> + /* Can't continue parsing without knowing hash size. */
> + break;
> + }
> +
> + rc = 0;
> +
> +error:
> + relinquish_locality(loc);
> + return rc;
> +}
> +
> +#else
> +
> +union tpm2_cmd_rsp {
> + /* Enough space for multiple hashes. */
> + uint8_t b[sizeof(struct tpm2_extend_cmd) + 1024];
> + struct tpm_cmd_hdr c;
> + struct tpm_rsp_hdr r;
> + struct tpm2_extend_cmd extend_c;
> + struct tpm2_extend_rsp extend_r;
> +};
> +
> +static uint32_t tpm20_pcr_extend(unsigned loc, uint32_t pcr_handle,
> + const struct tpm2_log_hashes *log_hashes)
> +{
> + union tpm2_cmd_rsp cmd_rsp;
> + unsigned o_size;
> + unsigned i;
> + uint8_t *p;
> +
> + cmd_rsp.extend_c = (struct tpm2_extend_cmd) {
> + .h.tag = swap16(TPM_ST_SESSIONS),
> + .h.ordinal = swap32(TPM2_PCR_Extend),
> + .pcrHandle = swap32(pcr_handle),
> + .sessionHdrSize = swap32(sizeof(struct tpm2_session_header)),
> + .pcrSession.handle = swap32(TPM_RS_PW),
> + .hashCount = swap32(log_hashes->count),
> + };
> +
> + p = cmd_rsp.extend_c.hashes;
> + for ( i = 0; i < log_hashes->count; ++i )
> + {
> + const struct tpm2_log_hash *hash = &log_hashes->hashes[i];
> +
> + if ( p + sizeof(uint16_t) + hash->size > &cmd_rsp.b[sizeof(cmd_rsp)] )
> + {
> + printk(XENLOG_ERR "Hit TPM message size implementation limit: %ld\n",
> + sizeof(cmd_rsp));
> + return -1;
> + }
> +
> + *(uint16_t *)p = swap16(hash->alg);
> + p += sizeof(uint16_t);
> +
> + memcpy(p, hash->data, hash->size);
> + p += hash->size;
> + }
> +
> + /* Fill in command size (size of the whole buffer). */
> + cmd_rsp.extend_c.h.paramSize = swap32(sizeof(cmd_rsp.extend_c) +
> + (p - cmd_rsp.extend_c.hashes)),
> +
> + o_size = sizeof(cmd_rsp);
> + send_cmd(loc, cmd_rsp.b, swap32(cmd_rsp.c.paramSize), &o_size);
> +
> + return swap32(cmd_rsp.r.returnCode);
> +}
> +
> +static bool tpm_supports_hash(unsigned loc, const struct tpm2_log_hash *hash)
> +{
> + uint32_t rc;
> + struct tpm2_log_hashes hashes = {
> + .count = 1,
> + .hashes[0] = *hash,
> + };
> +
> + /*
> + * This is a valid way of checking hash support, using it to not implement
> + * TPM2_GetCapability().
> + */
> + rc = tpm20_pcr_extend(loc, /*pcr_handle=*/TPM_RH_NULL, &hashes);
> +
> + return rc == 0;
> +}
> +
> +static uint32_t tpm2_hash_extend(unsigned loc, const uint8_t *buf,
> + unsigned size, unsigned pcr,
> + const struct tpm2_log_hashes *log_hashes)
> +{
> + uint32_t rc;
> + unsigned i;
> + struct tpm2_log_hashes supported_hashes = {0};
> +
> + request_locality(loc);
> +
> + for ( i = 0; i < log_hashes->count; ++i )
> + {
> + const struct tpm2_log_hash *hash = &log_hashes->hashes[i];
> + if ( !tpm_supports_hash(loc, hash) )
> + {
> + printk(XENLOG_WARNING "Skipped hash unsupported by TPM: %d\n",
> + hash->alg);
> + continue;
> + }
> +
> + if ( hash->alg == TPM_ALG_SHA1 )
> + {
> + sha1_hash(hash->data, buf, size);
> + }
> + else if ( hash->alg == TPM_ALG_SHA256 )
> + {
> + sha2_256_digest(hash->data, buf, size);
> + }
> + else
Is this really just "else", not "else if ( ... )"?
> + {
> + /* This is called "OneDigest" in TXT Software Development Guide. */
> + memset(hash->data, 0, size);
> + hash->data[0] = 1;
> + }
> +
> + if ( supported_hashes.count == MAX_HASH_COUNT )
> + {
> + printk(XENLOG_ERR "Hit hash count implementation limit: %d\n",
> + MAX_HASH_COUNT);
> + return -1;
This is an odd return value for a function returning uint32_t. And it's also ...
> @@ -419,6 +830,35 @@ void tpm_hash_extend(unsigned loc, unsigned pcr, const uint8_t *buf,
> {
> #ifndef __EARLY_SLAUNCH__
> printk(XENLOG_ERR "Extending PCR%u failed\n", pcr);
> +#endif
> + }
> + } else {
> + uint8_t sha1_digest[SHA1_DIGEST_SIZE];
> + uint8_t sha256_digest[SHA2_256_DIGEST_SIZE];
> + uint32_t rc;
> +
> + struct tpm2_log_hashes log_hashes = {
> + .count = 2,
> + .hashes = {
> + {
> + .alg = TPM_ALG_SHA1,
> + .size = SHA1_DIGEST_SIZE,
> + .data = sha1_digest,
> + },
> + {
> + .alg = TPM_ALG_SHA256,
> + .size = SHA2_256_DIGEST_SIZE,
> + .data = sha256_digest,
> + },
> + },
> + };
> +
> + rc = tpm2_hash_extend(loc, buf, size, pcr, &log_hashes);
> + if ( rc != 0 )
> + {
> +#ifndef __EARLY_SLAUNCH__
> + printk(XENLOG_ERR "Extending PCR%u failed with TPM error: 0x%08x\n",
> + pcr, rc);
... not exactly a TPM error.
Of course other comments given on the previous patch logically apply here (and
elsewhere) as well.
Jan
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