Re: [PATCH v2 3/3] tests/qtest: Introduce tests for AMD/Xilinx Versal TRNG device

[Francisco Iglesias]

Hi Tong,

On [2023 Sep 21] Thu 23:50:10, Tong Ho wrote:
> Signed-off-by: Tong Ho <tong.ho@amd.com>
> ---
>  tests/qtest/meson.build             |   2 +-
>  tests/qtest/xlnx-versal-trng-test.c | 490 ++++++++++++++++++++++++++++
>  2 files changed, 491 insertions(+), 1 deletion(-)
>  create mode 100644 tests/qtest/xlnx-versal-trng-test.c
> 
> diff --git a/tests/qtest/meson.build b/tests/qtest/meson.build
> index 1fba07f4ed..215d20e8cf 100644
> --- a/tests/qtest/meson.build
> +++ b/tests/qtest/meson.build
> @@ -216,7 +216,7 @@ qtests_aarch64 = \
>    (config_all.has_key('CONFIG_TCG') and 
> config_all_devices.has_key('CONFIG_TPM_TIS_SYSBUS') ?            \
>      ['tpm-tis-device-test', 'tpm-tis-device-swtpm-test'] : []) +             
>                             \
>    (config_all_devices.has_key('CONFIG_XLNX_ZYNQMP_ARM') ? ['xlnx-can-test', 
> 'fuzz-xlnx-dp-test'] : []) + \
> -  (config_all_devices.has_key('CONFIG_XLNX_VERSAL') ? ['xlnx-canfd-test'] : 
> []) + \
> +  (config_all_devices.has_key('CONFIG_XLNX_VERSAL') ? ['xlnx-canfd-test', 
> 'xlnx-versal-trng-test'] : []) + \
>    (config_all_devices.has_key('CONFIG_RASPI') ? ['bcm2835-dma-test'] : []) + 
>  \
>    (config_all.has_key('CONFIG_TCG') and                                      
>       \
>     config_all_devices.has_key('CONFIG_TPM_TIS_I2C') ? ['tpm-tis-i2c-test'] : 
> []) + \
.
.
.
> +
> +static const char *trng_info(void)
> +{
> +    uint32_t sta = trng_status();
> +    uint32_t ctl = trng_read(R_TRNG_CTRL);
> +
> +    static char info[64];
> +
> +    snprintf(info, sizeof(info), "; status=0x%x, ctrl=0x%x", sta, ctl);
> +    return info;
> +}
> +
> +static void trng_wait(uint32_t wait_mask, bool on, const char *act)

A suggestion is to remove the 'bool on' arg (it is only called with 'true'
below).

> +{
> +    time_t tmo = time(NULL) + 2; /* at most 2 seconds */
> +    uint32_t event_mask = 0;
> +    uint32_t clear_mask = 0;
> +
> +    /*
> +     * Only selected bits are events in R_TRNG_STATUS, and
> +     * clear them needs to go through R_INT_CTRL.
> +     */
> +    if (wait_mask & TRNG_STATUS_CERTF_MASK) {
> +        event_mask |= TRNG_STATUS_CERTF_MASK;
> +        clear_mask |= TRNG_INT_CTRL_CERTF_RST_MASK;
> +    }
> +    if (wait_mask & TRNG_STATUS_DTF_MASK) {
> +        event_mask |= TRNG_STATUS_DTF_MASK;
> +        clear_mask |= TRNG_INT_CTRL_DTF_RST_MASK;
> +    }
> +    if (wait_mask & TRNG_STATUS_DONE_MASK) {
> +        event_mask |= TRNG_STATUS_DONE_MASK;
> +        clear_mask |= TRNG_INT_CTRL_DONE_RST_MASK;
> +    }
> +
> +    for (;;) {
> +        bool sta = !!(trng_status() & event_mask);
> +
> +        if ((on ^ sta) == 0) {
> +            break;
> +        }
> +
> +        if (time(NULL) >= tmo) {
> +            FAILED("%s: Timed out waiting for event 0x%x to be %d%s",
> +                   act, event_mask, (int)on, trng_info());
> +        }
> +
> +        g_usleep(10000);
> +    }
> +
> +    /* Remove event */
> +    trng_bit_set(R_TRNG_INT_CTRL, clear_mask);
> +
> +    if (!!(trng_read(R_TRNG_STATUS) & event_mask)) {
> +        FAILED("%s: Event 0x%0x stuck at 1 after clear: %s",
> +               act, event_mask, trng_info());
> +    }
> +}
> +
> +static void trng_wait_done(const char *act)
> +{
> +    trng_wait(TRNG_STATUS_DONE_MASK, true, act);
> +}
> +
> +static void trng_wait_dtf(void)
> +{
> +    trng_wait(TRNG_STATUS_DTF_MASK, true, "DTF injection");
> +}
> +
> +static void trng_wait_certf(void)
> +{
> +    trng_wait(TRNG_STATUS_CERTF_MASK, true, "CERTF injection");
> +}
> +
> +static void trng_reset(void)
> +{
> +    trng_write(R_TRNG_RESET, TRNG_RESET_VAL_MASK);
> +    trng_write(R_TRNG_RESET, 0);
> +}
> +
> +static void trng_load(unsigned r0, const uint32_t *b384)
> +{
> +    static const uint32_t zero[12] = { 0 };
> +    unsigned k;
> +
> +    if (!b384) {
> +        b384 = zero;
> +    }
> +
> +    for (k = 0; k < 12; k++) {
> +        trng_write(r0 + 4 * k, b384[k]);
> +    }
> +}
> +
> +static void trng_reseed(const uint32_t *seed)
> +{
> +    const char *act;
> +    uint32_t ctl;
> +
> +    ctl = TRNG_CTRL_PRNGSTART_MASK |
> +          TRNG_CTRL_PRNGXS_MASK |
> +          TRNG_CTRL_TRSSEN_MASK;
> +
> +    trng_ctrl_clr(ctl | TRNG_CTRL_PRNGMODE_MASK);
> +
> +    if (seed) {
> +        trng_load(R_TRNG_EXT_SEED_0, seed);
> +        act = "Reseed PRNG";
> +        ctl &= ~TRNG_CTRL_TRSSEN_MASK;
> +    } else {
> +        trng_write(R_TRNG_OSC_EN, TRNG_OSC_EN_VAL_MASK);
> +        act = "Reseed TRNG";
> +        ctl &= ~TRNG_CTRL_PRNGXS_MASK;
> +    }
> +
> +    trng_ctrl_set(ctl);
> +    trng_wait_done(act);
> +    trng_ctrl_clr(TRNG_CTRL_PRNGSTART_MASK);
> +}
> +
> +static void trng_generate(bool auto_enb)
> +{
> +    uint32_t ctl;
> +
> +    ctl = TRNG_CTRL_PRNGSTART_MASK | TRNG_CTRL_SINGLEGENMODE_MASK;
> +    trng_ctrl_clr(ctl);
> +
> +    if (auto_enb) {
> +        ctl &= ~TRNG_CTRL_SINGLEGENMODE_MASK;
> +    }
> +
> +    trng_ctrl_set(ctl | TRNG_CTRL_PRNGMODE_MASK);
> +
> +    trng_wait_done("Generate");
> +    g_assert(trng_qcnt() != 7);
> +}
> +
> +static size_t trng_collect(uint32_t *rnd, size_t cnt)
> +{
> +    size_t i;
> +
> +    for (i = 0; i < cnt; i++) {
> +        if (trng_qcnt() == 0) {
> +            return i;
> +        }
> +
> +        rnd[i] = trng_read(R_TRNG_CORE_OUTPUT);
> +    }
> +
> +    return i;
> +}
> +
> +static void trng_test_autogen(void)
> +{
> +    const size_t cnt = 512 / 32;
> +    uint32_t rng[cnt], prng[cnt];
> +    size_t n;
> +
> +    trng_reset();
> +
> +    /* PRNG run #1 */
> +    trng_reseed(prng_seed);
> +    trng_generate(true);
> +
> +    n = trng_collect(prng, cnt);
> +    if (n != cnt) {
> +        FAILED("PRNG_1 Auto-gen test failed: expected = %u, got = %u",
> +               (unsigned)cnt, (unsigned)n);
> +    }
> +
> +    /* TRNG, should not match PRNG */
> +    trng_reseed(NULL);
> +    trng_generate(true);
> +
> +    n = trng_collect(rng, cnt);
> +    if (n != cnt) {
> +        FAILED("TRNG Auto-gen test failed: expected = %u, got = %u",
> +               (unsigned)cnt, (unsigned)n);
> +    }
> +
> +    if (!memcmp(rng, prng, sizeof(rng))) {
> +        FAILED("TRNG test failed: matching PRNG");
> +    }
> +
> +    /* PRNG #2: should matches run #1 */
> +    trng_reseed(prng_seed);
> +    trng_generate(true);
> +
> +    n = trng_collect(rng, cnt);
> +    if (n != cnt) {
> +        FAILED("PRNG_2 Auto-gen test failed: expected = %u, got = %u",
> +               (unsigned)cnt, (unsigned)n);
> +    }
> +
> +    if (memcmp(rng, prng, sizeof(rng))) {
> +        FAILED("PRNG_2 Auto-gen test failed: does not match PRNG_1");
> +    }
> +}
> +
> +static void trng_test_oneshot(void)
> +{
> +    const size_t cnt = 512 / 32;
> +    uint32_t rng[cnt];
> +    size_t n;
> +
> +    trng_reset();
> +
> +    /* PRNG run #1 */
> +    trng_reseed(prng_seed);
> +    trng_generate(false);
> +
> +    n = trng_collect(rng, cnt);
> +    if (n == cnt) {
> +        FAILED("PRNG_1 One-shot gen test failed");
> +    }
> +
> +    /* TRNG, should not match PRNG */
> +    trng_reseed(NULL);
> +    trng_generate(false);
> +
> +    n = trng_collect(rng, cnt);
> +    if (n == cnt) {
> +        FAILED("TRNG One-shot test failed");
> +    }
> +}
> +
> +static void trng_test_per_str(void)
> +{
> +    const size_t cnt = 512 / 32;
> +    uint32_t rng[cnt], prng[cnt];
> +    size_t n;
> +
> +    trng_reset();
> +
> +    /* #1: disabled */
> +    trng_ctrl_set(TRNG_CTRL_PERSODISABLE_MASK);
> +    trng_reseed(prng_seed);
> +    trng_ctrl_clr(TRNG_CTRL_PERSODISABLE_MASK);
> +
> +    trng_generate(true);
> +    n = trng_collect(prng, cnt);
> +    g_assert_cmpuint(n, ==, cnt);
> +
> +    /* #2: zero string should match personalization disabled */
> +    trng_load(R_TRNG_PER_STRNG_0, NULL);
> +    trng_reseed(prng_seed);
> +
> +    trng_generate(true);
> +    n = trng_collect(rng, cnt);
> +    g_assert_cmpuint(n, ==, cnt);
> +
> +    if (memcmp(rng, prng, sizeof(rng))) {
> +        FAILED("Failed: PER_DISABLE != PER_STRNG_ALL_ZERO");
> +    }
> +
> +    /* #3: non-zero string should not match personalization disabled */
> +    trng_load(R_TRNG_PER_STRNG_0, pers_str);
> +    trng_reseed(prng_seed);
> +
> +    trng_generate(true);
> +    n = trng_collect(rng, cnt);
> +    g_assert_cmpuint(n, ==, cnt);
> +
> +    if (!memcmp(rng, prng, sizeof(rng))) {
> +        FAILED("Failed: PER_DISABLE == PER_STRNG_NON_ZERO");
> +    }
> +}
> +
> +static void trng_test_forced_prng(void)
> +{
> +    const char *prop = "forced-prng";
> +    const uint64_t seed = 0xdeadbeefbad1bad0ULL;
> +
> +    trng_reset();

We need to move above line below the variable initialization below.

> +    const size_t cnt = 512 / 32;
> +    uint32_t rng[cnt], prng[cnt];
> +    size_t n;

Looks good to me otherwise!

Best regards,
Francisco Iglesias

> +
> +    trng_test_set_uint_prop(prop, seed);
> +
> +    /* TRNG run #1 */
> +    trng_reset();
> +    trng_reseed(NULL);
> +    trng_generate(true);
> +
> +    n = trng_collect(prng, cnt);
> +    g_assert_cmpuint(n, ==, cnt);
> +
> +    /* TRNG run #2 should match run #1 */
> +    trng_reset();
> +    trng_reseed(NULL);
> +    trng_generate(true);
> +
> +    n = trng_collect(rng, cnt);
> +    g_assert_cmpuint(n, ==, cnt);
> +
> +    if (memcmp(rng, prng, sizeof(rng))) {
> +        FAILED("Forced-prng test failed: results do not match");
> +    }
> +}
> +
> +static void trng_test_fault_events(void)
> +{
> +    const char *prop = "fips-fault-events";
> +
> +    trng_reset();
> +
> +    /* Fault events only when TRSS is enabled */
> +    trng_write(R_TRNG_OSC_EN, TRNG_OSC_EN_VAL_MASK);
> +    trng_ctrl_set(TRNG_CTRL_TRSSEN_MASK);
> +
> +    trng_test_set_uint_prop(prop, TRNG_STATUS_CERTF_MASK);
> +    trng_wait_certf();
> +
> +    trng_test_set_uint_prop(prop, TRNG_STATUS_DTF_MASK);
> +    trng_wait_dtf();
> +
> +    trng_reset();
> +}
> +
> +int main(int argc, char **argv)
> +{
> +    int rc;
> +
> +    g_test_init(&argc, &argv, NULL);
> +
> +    #define TRNG_TEST_ADD(n) \
> +            qtest_add_func("/hw/misc/xlnx-versal-trng/" #n, trng_test_ ## n);
> +    TRNG_TEST_ADD(autogen);
> +    TRNG_TEST_ADD(oneshot);
> +    TRNG_TEST_ADD(per_str);
> +    TRNG_TEST_ADD(forced_prng);
> +    TRNG_TEST_ADD(fault_events);
> +    #undef TRNG_TEST_ADD
> +
> +    trng_test_start();
> +    rc = g_test_run();
> +    trng_test_stop();
> +
> +    return rc;
> +}
> -- 
> 2.25.1
> 
>