[kvm-unit-tests PATCH 4/4] s390x: uv-guest: Add attestation tests

Steffen Eiden
2022-01-27T14:16:16Z

Adds several tests to verify correct error paths of attestation.

Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
lib/s390x/asm/uv.h | 5 +-
s390x/uv-guest.c | 164 +++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 168 insertions(+), 1 deletion(-)

diff --git a/lib/s390x/asm/uv.h b/lib/s390x/asm/uv.h
index 38c322bf..e8e1698e 100644
--- a/lib/s390x/asm/uv.h
+++ b/lib/s390x/asm/uv.h
@@ -109,7 +109,10 @@ struct uv_cb_qui {
u8 reserved88[158 - 136]; /* 0x0088 */
uint16_t max_guest_cpus; /* 0x009e */
u64 uv_feature_indications; /* 0x00a0 */
- u8 reserveda8[200 - 168]; /* 0x00a8 */
+ u8 reserveda8[224 - 168]; /* 0x00a8 */
+ u64 supported_att_hdr_versions; /* 0x00e0 */
+ u64 supported_paf; /* 0x00e8 */
+ u8 reservedf0[256 - 240]; /* 0x00f0 */
} __attribute__((packed)) __attribute__((aligned(8)));

struct uv_cb_cgc {
diff --git a/s390x/uv-guest.c b/s390x/uv-guest.c
index 909b7256..92b9a53b 100644
--- a/s390x/uv-guest.c
+++ b/s390x/uv-guest.c
@@ -6,6 +6,7 @@
*
* Authors:
* Janosch Frank <frankja@linux.ibm.com>
+ * Steffen Eiden <seiden@linux.ibm.com>
*/

#include <libcflat.h>
@@ -53,6 +54,15 @@ static void test_priv(void)
check_pgm_int_code(PGM_INT_CODE_PRIVILEGED_OPERATION);
report_prefix_pop();

+ report_prefix_push("attest");
+ uvcb.cmd = UVC_CMD_ATTESTATION;
+ uvcb.len = sizeof(struct uv_cb_attest);
+ expect_pgm_int();
+ enter_pstate();
+ uv_call_once(0, (u64)&uvcb);
+ check_pgm_int_code(PGM_INT_CODE_PRIVILEGED_OPERATION);
+ report_prefix_pop();
+
report_prefix_pop();
}

@@ -111,7 +121,160 @@ static void test_sharing(void)
cc = uv_call(0, (u64)&uvcb);
report(cc == 0 && uvcb.header.rc == UVC_RC_EXECUTED, "unshare");
report_prefix_pop();
+}
+
+/* arcb with one key slot and no nonce */
+struct uv_arcb_v1 {
+ uint64_t reserved0; /* 0x0000 */
+ uint32_t arvn; /* 0x0008 */
+ uint32_t arl; /* 0x000c */
+ uint8_t iv[12]; /* 0x0010 */
+ uint32_t reserved1c; /* 0x001c */
+ uint8_t reserved20[7]; /* 0x0020 */
+ uint8_t nks; /* 0x0027 */
+ uint32_t reserved28; /* 0x0028 */
+ uint32_t sea; /* 0x002c */
+ uint64_t paf; /* 0x0030 */
+ uint32_t mai; /* 0x0038 */
+ uint32_t reserved3c; /* 0x003c */
+ uint8_t cpk[160]; /* 0x0040 */
+ uint8_t key_slot[80]; /* 0x00e0 */
+ uint8_t m_key[64]; /* 0x0130 */
+ uint8_t tag[16]; /* 0x0170 */
+} __attribute__((packed));
+
+static void test_attest_v1(u64 supported_paf)
+{
+ struct uv_cb_attest uvcb = {
+ .header.cmd = UVC_CMD_ATTESTATION,
+ .header.len = sizeof(uvcb),
+ };
+ struct uv_arcb_v1 *arcb = (void *)page;
+ uint64_t measurement = page + sizeof(*arcb);
+ size_t measurement_size = 64;
+ uint64_t additional = measurement + measurement_size;
+ size_t additional_size = 64;
+ int cc;
+
+ memset((void *) page, 0, PAGE_SIZE);
+
+ /* create a minimal arcb/uvcb such that FW has everything to start unsealing the request. */
+ arcb->arvn = 0x0100;
+ arcb->arl = sizeof(*arcb);
+ arcb->nks = 1;
+ arcb->sea = 64;
+ /* HMAC SHA512 */
+ arcb->mai = 1;
+ uvcb.arcb_addr = page;
+ uvcb.measurement_address = measurement;
+ uvcb.measurement_length = measurement_size;
+ uvcb.add_data_address = additional;
+ uvcb.add_data_length = additional_size;
+
+ uvcb.continuation_token = 0xff;
+ cc = uv_call(0, (u64)&uvcb);
+ report(cc == 1 && uvcb.header.rc == 0x0101, "invalid continuation token");
+ uvcb.continuation_token = 0;
+
+ uvcb.user_data_length = sizeof(uvcb.user_data) + 1;
+ cc = uv_call(0, (u64)&uvcb);
+ report(cc == 1 && uvcb.header.rc == 0x0102, "invalid user data size");
+ uvcb.user_data_length = 0;
+
+ uvcb.arcb_addr = 0;
+ cc = uv_call(0, (u64)&uvcb);
+ report(cc == 1 && uvcb.header.rc == 0x0103, "invalid address arcb");
+ uvcb.arcb_addr = page;
+
+ /* 0104 - 0105 need an unseal-able request */
+
+ /* version 0000 is an illegal version number */
+ arcb->arvn = 0x0000;
+ cc = uv_call(0, (u64)&uvcb);
+ report(cc == 1 && uvcb.header.rc == 0x0106, "unsupported version");
+ arcb->arvn = 0x0100;
+
+ arcb->arl += 1;
+ cc = uv_call(0, (u64)&uvcb);
+ report(cc == 1 && uvcb.header.rc == 0x0107, "invalid arcb size 1");
+ arcb->arl -= 1;
+ arcb->nks = 2;
+ cc = uv_call(0, (u64)&uvcb);
+ report(cc == 1 && uvcb.header.rc == 0x0107, "invalid arcb size 2");
+ arcb->nks = 1;
+
+ arcb->nks = 0;
+ cc = uv_call(0, (u64)&uvcb);
+ report(cc == 1 && uvcb.header.rc == 0x0108, "invalid num key slots low");
+ arcb->nks = 1;

+ /* possible valid size (when using nonce). However, arl to small to host a nonce */
+ arcb->sea = 80;
+ cc = uv_call(0, (u64)&uvcb);
+ report(cc == 1 && uvcb.header.rc == 0x0109, "invalid encrypted size 1");
+ arcb->sea = 17;
+ cc = uv_call(0, (u64)&uvcb);
+ report(cc == 1 && uvcb.header.rc == 0x0109, "invalid encrypted size 2");
+ arcb->sea = 64;
+
+ arcb->paf = supported_paf ^ ((u64) -1);
+ cc = uv_call(0, (u64)&uvcb);
+ report(cc == 1 && uvcb.header.rc == 0x010a, "invalid paf");
+ arcb->paf = 0;
+
+ /* reserved value */
+ arcb->mai = 0;
+ cc = uv_call(0, (u64)&uvcb);
+ report(cc == 1 && uvcb.header.rc == 0x010b, "invalid mai");
+ arcb->mai = 1;
+
+ cc = uv_call(0, (u64)&uvcb);
+ report(cc == 1 && uvcb.header.rc == 0x010c, "unable unseal");
+
+ uvcb.measurement_length = 0;
+ cc = uv_call(0, (u64)&uvcb);
+ report(cc == 1 && uvcb.header.rc == 0x010d, "invalid measurement size");
+ uvcb.measurement_length = 64;
+}
+
+static void test_attest(void)
+{
+ struct uv_cb_attest uvcb = {
+ .header.cmd = UVC_CMD_ATTESTATION,
+ .header.len = sizeof(uvcb),
+ };
+ const struct uv_cb_qui *uvcb_qui = uv_get_info();
+ int cc;
+
+ report_prefix_push("attest");
+
+ if (!uv_query_test_call(BIT_UVC_CMD_ATTESTATION)) {
+ report_skip("Attestation not supported.");
+ goto done;
+ }
+
+ /* Verify that the uv supports at least one header version */
+ report(uvcb_qui->supported_att_hdr_versions, "has hdr support");
+
+ memset((void *) page, 0, PAGE_SIZE);
+
+ uvcb.header.len -= 1;
+ cc = uv_call(0, (u64)&uvcb);
+ report(cc && uvcb.header.rc == UVC_RC_INV_LEN, "invalid uvcb size 1");
+ uvcb.header.len += 1;
+
+ uvcb.header.len += 1;
+ cc = uv_call(0, (u64)&uvcb);
+ report(cc && uvcb.header.rc == UVC_RC_INV_LEN, "invalid uvcb size 2");
+ uvcb.header.len -= 1;
+
+ report_prefix_push("v1");
+ if (test_bit_inv(0, &uvcb_qui->supported_att_hdr_versions))
+ test_attest_v1(uvcb_qui->supported_paf);
+ else
+ report_skip("Attestation version 1 not supported");
+ report_prefix_pop();
+done:
report_prefix_pop();
}

@@ -179,6 +342,7 @@ int main(void)
test_invalid();
test_query();
test_sharing();
+ test_attest();
free_page((void *)page);
done:
report_prefix_pop();
--
2.30.2