Support CPACF pcc subfunctions PCC-Compute-XTS-Parameter-Encrypted-AES-128
and PCC-Compute-XTS-Parameter-Encrypted-AES-128 but only for the special
case block sequential number is 0. However, this covers the s390 PAES XTS
implementation in the Linux kernel.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
---
 target/s390x/gen-features.c      |  2 +
 target/s390x/tcg/cpacf.h         |  2 +
 target/s390x/tcg/cpacf_aes.c     | 79 ++++++++++++++++++++++++++++++++
 target/s390x/tcg/crypto_helper.c |  4 ++
 4 files changed, 87 insertions(+)

diff --git a/target/s390x/gen-features.c b/target/s390x/gen-features.c
index 4a131dc191..126bacb281 100644
--- a/target/s390x/gen-features.c
+++ b/target/s390x/gen-features.c
@@ -943,6 +943,8 @@ static uint16_t qemu_MAX[] = {
     S390_FEAT_KMCTR_EAES_256,
     S390_FEAT_PCC_XTS_AES_128,
     S390_FEAT_PCC_XTS_AES_256,
+    S390_FEAT_PCC_XTS_EAES_128,
+    S390_FEAT_PCC_XTS_EAES_256,
     S390_FEAT_PCKMO_AES_128,
     S390_FEAT_PCKMO_AES_192,
     S390_FEAT_PCKMO_AES_256,
diff --git a/target/s390x/tcg/cpacf.h b/target/s390x/tcg/cpacf.h
index 35518aef4b..9d0801b217 100644
--- a/target/s390x/tcg/cpacf.h
+++ b/target/s390x/tcg/cpacf.h
@@ -42,5 +42,7 @@ int cpacf_paes_cbc(CPUS390XState *env, uintptr_t ra, uint64_t param_addr,
 int cpacf_paes_ctr(CPUS390XState *env, uintptr_t ra, uint64_t param_addr,
                    uint64_t *dst_ptr, uint64_t *src_ptr, uint64_t *src_len,
                    uint64_t *ctr_ptr, uint32_t type, uint8_t fc, uint8_t mod);
+int cpacf_paes_pcc(CPUS390XState *env, uintptr_t ra, uint64_t param_addr,
+                   uint8_t fc);
 
 #endif
diff --git a/target/s390x/tcg/cpacf_aes.c b/target/s390x/tcg/cpacf_aes.c
index 78af0ce8d5..c4406f4a34 100644
--- a/target/s390x/tcg/cpacf_aes.c
+++ b/target/s390x/tcg/cpacf_aes.c
@@ -786,3 +786,82 @@ int cpacf_paes_ctr(CPUS390XState *env, uintptr_t ra, uint64_t param_addr,
 
     return !len ? 0 : 3;
 }
+
+int cpacf_paes_pcc(CPUS390XState *env, uintptr_t ra, uint64_t param_addr,
+                   uint8_t fc)
+{
+    uint8_t key[32], wkvp[32], tweak[AES_BLOCK_SIZE], buf[AES_BLOCK_SIZE];
+    int keysize, i;
+    uint64_t addr;
+    AES_KEY exkey;
+
+    switch (fc) {
+    case 0x3a: /* CPACF_PCC compute XTS param Encrypted AES-128 */
+        keysize = 16;
+        break;
+    case 0x3c: /* CPACF PCC compute XTS param Encrypted AES-256 */
+        keysize = 32;
+        break;
+    default:
+        g_assert_not_reached();
+    }
+
+    /* fetch and check wkvp from param block */
+    for (i = 0; i < sizeof(wkvp); i++) {
+        addr = wrap_address(env, param_addr + keysize + i);
+        wkvp[i] = cpu_ldub_data_ra(env, addr, ra);
+    }
+    if (memcmp(wkvp, protkey_wkvp, sizeof(wkvp))) {
+        /* wkvp mismatch -> return with cc 1 */
+        return 1;
+    }
+
+    /* fetch block sequence nr from param block into buf */
+    for (i = 0; i < AES_BLOCK_SIZE; i++) {
+        addr = wrap_address(env, param_addr + keysize +
+                            sizeof(wkvp) + AES_BLOCK_SIZE + i);
+        buf[i] = cpu_ldub_data_ra(env, addr, ra);
+    }
+
+    /* is the block sequence nr 0 ? */
+    for (i = 0; i < AES_BLOCK_SIZE && !buf[i]; i++) {
+            ;
+    }
+    if (i < AES_BLOCK_SIZE) {
+        /* no, sorry handling of non zero block sequence is not implemented */
+        cpu_abort(env_cpu(env),
+                  "PCC-compute-XTS-param (encrypted) with non zero block seq nr is not implemented\n");
+        return 1;
+    }
+
+    /* fetch protected key from param block */
+    for (i = 0; i < keysize; i++) {
+        addr = wrap_address(env, param_addr + i);
+        key[i] = cpu_ldub_data_ra(env, addr, ra);
+    }
+    /* 'decrypt' the protected key */
+    for (i = 0; i < keysize; i++) {
+        key[i] ^= protkey_xor_pattern[i];
+    }
+
+    /* fetch tweak from param block into tweak */
+    for (i = 0; i < AES_BLOCK_SIZE; i++) {
+        addr = wrap_address(env, param_addr + keysize + sizeof(wkvp) + i);
+        tweak[i] = cpu_ldub_data_ra(env, addr, ra);
+    }
+
+    /* expand key */
+    AES_set_encrypt_key(key, keysize * 8, &exkey);
+
+    /* encrypt tweak */
+    AES_encrypt(tweak, buf, &exkey);
+
+    /* store encrypted tweak into xts parameter field of the param block */
+    for (i = 0; i < AES_BLOCK_SIZE; i++) {
+        addr = wrap_address(env, param_addr + keysize +
+                            sizeof(wkvp) + 3 * AES_BLOCK_SIZE + i);
+        cpu_stb_data_ra(env, addr, buf[i], ra);
+    }
+
+    return 0;
+}
diff --git a/target/s390x/tcg/crypto_helper.c b/target/s390x/tcg/crypto_helper.c
index 2791e69f84..3ff8331993 100644
--- a/target/s390x/tcg/crypto_helper.c
+++ b/target/s390x/tcg/crypto_helper.c
@@ -201,6 +201,10 @@ static int cpacf_pcc(CPUS390XState *env, uintptr_t ra, uint8_t fc)
     case 0x34: /* CPACF PCC compute XTS param AES-256 */
             rc = cpacf_aes_pcc(env, ra, env->regs[1], fc);
             break;
+    case 0x3a: /* CPACF_PCC compute XTS param Encrypted AES-128 */
+    case 0x3c: /* CPACF PCC compute XTS param Encrypted AES-256 */
+            rc = cpacf_paes_pcc(env, ra, env->regs[1], fc);
+            break;
     default:
         g_assert_not_reached();
     }
-- 
2.43.0