[PATCH v6 09/17] target/s390x: Support pckmo encrypt AES subfunctions

[Harald Freudenberger <freude@linux.ibm.com>]

Support the subfuctions PCKMO-Encrypt-AES-128-Key,
PCKMO-Encrypt-AES-192-Key and PCKMO-Encrypt-AES-256-Key.

These subfunctions derive a protected key from an AES clear key
by encrypting it with an internal AES wrapping key. More
details can be found in the "z/Architecture Prinziples of
Operation" document.

The qemu version provided here is only a fake indented to make
protected key available for developing and testing purpose:
* The protected key is 'derived' from the clear key by xoring
  the fixed pattern 0xAAAA... onto the key value.
* The AES Wrapping Key Verification Pattern is a fixed
  value of 32 bytes 0xFACEFACE...

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Tested-by: Holger Dengler <dengler@linux.ibm.com>
---
 target/s390x/gen-features.c      |  3 ++
 target/s390x/tcg/cpacf.h         |  2 +
 target/s390x/tcg/cpacf_aes.c     | 66 ++++++++++++++++++++++++++++++++
 target/s390x/tcg/crypto_helper.c | 21 ++++++++++
 4 files changed, 92 insertions(+)

diff --git a/target/s390x/gen-features.c b/target/s390x/gen-features.c
index f9b1a40c7c..d3e69aaca6 100644
--- a/target/s390x/gen-features.c
+++ b/target/s390x/gen-features.c
@@ -934,6 +934,9 @@ static uint16_t qemu_MAX[] = {
     S390_FEAT_KMCTR_AES_256,
     S390_FEAT_PCC_XTS_AES_128,
     S390_FEAT_PCC_XTS_AES_256,
+    S390_FEAT_PCKMO_AES_128,
+    S390_FEAT_PCKMO_AES_192,
+    S390_FEAT_PCKMO_AES_256,
 };
 
 /****** END FEATURE DEFS ******/
diff --git a/target/s390x/tcg/cpacf.h b/target/s390x/tcg/cpacf.h
index 7e53ce2a14..5588e2bdec 100644
--- a/target/s390x/tcg/cpacf.h
+++ b/target/s390x/tcg/cpacf.h
@@ -38,5 +38,7 @@ int cpacf_aes_xts(CPUS390XState *env, const int mmu_idx, uintptr_t ra,
                   uint64_t param_addr, uint64_t *dst_ptr_reg,
                   uint64_t *src_ptr_reg, uint64_t *src_len_reg,
                   uint32_t type, uint8_t fc, uint8_t mod);
+int cpacf_aes_pckmo(CPUS390XState *env, const int mmu_idx, 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 0312436c43..5a0a3473d5 100644
--- a/target/s390x/tcg/cpacf_aes.c
+++ b/target/s390x/tcg/cpacf_aes.c
@@ -467,3 +467,69 @@ int cpacf_aes_xts(CPUS390XState *env, const int mmu_idx, uintptr_t ra,
 
     return !len ? 0 : 3;
 }
+
+/*
+ * Hard coded pattern xored with the AES clear key
+ * to 'produce' the protected key.
+ */
+static const uint8_t protkey_xor_pattern[32] = {
+    0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA,
+    0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA,
+    0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA,
+    0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA };
+
+/*
+ * Hard coded wkvp ("Wrapping Key Verification Pattern")
+ */
+static const uint8_t protkey_wkvp[32] = {
+    0x0F, 0x0A, 0x0C, 0x0E, 0x0F, 0x0A, 0x0C, 0x0E,
+    0x0F, 0x0A, 0x0C, 0x0E, 0x0F, 0x0A, 0x0C, 0x0E,
+    0x0F, 0x0A, 0x0C, 0x0E, 0x0F, 0x0A, 0x0C, 0x0E,
+    0x0F, 0x0A, 0x0C, 0x0E, 0x0F, 0x0A, 0x0C, 0x0E };
+
+int cpacf_aes_pckmo(CPUS390XState *env, const int mmu_idx, uintptr_t ra,
+                    uint64_t param_addr, uint8_t fc)
+{
+    const MemOpIdx oi = make_memop_idx(MO_8, mmu_idx);
+    uint8_t key[32];
+    int keysize, i;
+    uint64_t addr;
+
+    switch (fc) {
+    case 0x12: /* CPACF_PCKMO_ENC_AES_128_KEY */
+        keysize = 16;
+        break;
+    case 0x13: /* CPACF_PCKMO_ENC_AES_192_KEY */
+        keysize = 24;
+        break;
+    case 0x14: /* CPACF_PCKMO_ENC_AES_256_KEY */
+        keysize = 32;
+        break;
+    default:
+        g_assert_not_reached();
+    }
+
+    /* fetch key from param block */
+    for (i = 0; i < keysize; i++) {
+        addr = wrap_address(env, param_addr + i);
+        key[i] = cpu_ldb_mmu(env, addr, oi, ra);
+    }
+
+    /* 'derive' the protected key */
+    for (i = 0; i < keysize; i++) {
+        key[i] ^= protkey_xor_pattern[i];
+    }
+
+    /* store the protected key into param block */
+    for (i = 0; i < keysize; i++) {
+        addr = wrap_address(env, param_addr + i);
+        cpu_stb_mmu(env, addr, key[i], oi, ra);
+    }
+    /* followed by the fake wkvp */
+    for (i = 0; i < sizeof(protkey_wkvp); i++) {
+        addr = wrap_address(env, param_addr + keysize + i);
+        cpu_stb_mmu(env, addr, protkey_wkvp[i], oi, ra);
+    }
+
+    return 0;
+}
diff --git a/target/s390x/tcg/crypto_helper.c b/target/s390x/tcg/crypto_helper.c
index 19d625f37f..e1952ae4bc 100644
--- a/target/s390x/tcg/crypto_helper.c
+++ b/target/s390x/tcg/crypto_helper.c
@@ -192,6 +192,24 @@ static int cpacf_pcc(CPUS390XState *env, const int mmu_idx, uintptr_t ra,
     return rc;
 }
 
+static int cpacf_pckmo(CPUS390XState *env, const int mmu_idx, uintptr_t ra,
+                       uint8_t fc)
+{
+    int rc = 0;
+
+    switch (fc) {
+    case 0x12: /* CPACF_PCKMO_ENC_AES_128_KEY */
+    case 0x13: /* CPACF_PCKMO_ENC_AES_192_KEY */
+    case 0x14: /* CPACF_PCKMO_ENC_AES_256_KEY */
+        rc = cpacf_aes_pckmo(env, mmu_idx, ra, env->regs[1], fc);
+        break;
+    default:
+        g_assert_not_reached();
+    }
+
+    return rc;
+}
+
 uint32_t HELPER(msa)(CPUS390XState *env, uint32_t r1, uint32_t r2, uint32_t r3,
                      uint32_t type)
 {
@@ -254,6 +272,9 @@ uint32_t HELPER(msa)(CPUS390XState *env, uint32_t r1, uint32_t r2, uint32_t r3,
     case S390_FEAT_TYPE_PCC:
         rc = cpacf_pcc(env, mmu_idx, ra, fc);
         break;
+    case S390_FEAT_TYPE_PCKMO:
+        rc = cpacf_pckmo(env, mmu_idx, ra, fc);
+        break;
     default:
         g_assert_not_reached();
     }
-- 
2.43.0