On 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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