[PATCH 01/18] crypto: Add generic 8-bit carry-less multiply routines

[Richard Henderson <richard.henderson@linaro.org>]

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 host/include/generic/host/crypto/clmul.h | 17 ++++++
 include/crypto/clmul.h                   | 61 +++++++++++++++++++
 crypto/clmul.c                           | 76 ++++++++++++++++++++++++
 crypto/meson.build                       |  9 ++-
 4 files changed, 160 insertions(+), 3 deletions(-)
 create mode 100644 host/include/generic/host/crypto/clmul.h
 create mode 100644 include/crypto/clmul.h
 create mode 100644 crypto/clmul.c

diff --git a/host/include/generic/host/crypto/clmul.h b/host/include/generic/host/crypto/clmul.h
new file mode 100644
index 0000000000..694705f703
--- /dev/null
+++ b/host/include/generic/host/crypto/clmul.h
@@ -0,0 +1,17 @@
+/*
+ * No host specific carry-less multiply acceleration.
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#ifndef GENERIC_HOST_CRYPTO_CLMUL_H
+#define GENERIC_HOST_CRYPTO_CLMUL_H
+
+/* Defer everything to the generic routines. */
+#define clmul_8x8_low           clmul_8x8_low_gen
+#define clmul_8x4_even          clmul_8x4_even_gen
+#define clmul_8x4_odd           clmul_8x4_odd_gen
+#define clmul_8x8_even          clmul_8x8_even_gen
+#define clmul_8x8_odd           clmul_8x8_odd_gen
+#define clmul_8x8_packed        clmul_8x8_packed_gen
+
+#endif /* GENERIC_HOST_CRYPTO_CLMUL_H */
diff --git a/include/crypto/clmul.h b/include/crypto/clmul.h
new file mode 100644
index 0000000000..7f19205d6f
--- /dev/null
+++ b/include/crypto/clmul.h
@@ -0,0 +1,61 @@
+/*
+ * Carry-less multiply
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * Copyright (C) 2023 Linaro, Ltd.
+ */
+
+#ifndef CRYPTO_CLMUL_H
+#define CRYPTO_CLMUL_H
+
+#include "qemu/int128.h"
+
+/**
+ * clmul_8x8_low:
+ *
+ * Perform eight 8x8->8 carry-less multiplies.
+ */
+uint64_t clmul_8x8_low_gen(uint64_t, uint64_t);
+
+/**
+ * clmul_8x4_even:
+ *
+ * Perform four 8x8->16 carry-less multiplies.
+ * The odd bytes of the inputs are ignored.
+ */
+uint64_t clmul_8x4_even_gen(uint64_t, uint64_t);
+
+/**
+ * clmul_8x4_odd:
+ *
+ * Perform four 8x8->16 carry-less multiplies.
+ * The even bytes of the inputs are ignored.
+ */
+uint64_t clmul_8x4_odd_gen(uint64_t, uint64_t);
+
+/**
+ * clmul_8x8_even:
+ *
+ * Perform eight 8x8->16 carry-less multiplies.
+ * The odd bytes of the inputs are ignored.
+ */
+Int128 clmul_8x8_even_gen(Int128, Int128);
+
+/**
+ * clmul_8x8_odd:
+ *
+ * Perform eight 8x8->16 carry-less multiplies.
+ * The even bytes of the inputs are ignored.
+ */
+Int128 clmul_8x8_odd_gen(Int128, Int128);
+
+/**
+ * clmul_8x8_packed:
+ *
+ * Perform eight 8x8->16 carry-less multiplies.
+ */
+Int128 clmul_8x8_packed_gen(uint64_t, uint64_t);
+
+#include "host/crypto/clmul.h"
+
+#endif /* CRYPTO_CLMUL_H */
diff --git a/crypto/clmul.c b/crypto/clmul.c
new file mode 100644
index 0000000000..866704e751
--- /dev/null
+++ b/crypto/clmul.c
@@ -0,0 +1,76 @@
+/*
+ * No host specific carry-less multiply acceleration.
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "qemu/osdep.h"
+#include "crypto/clmul.h"
+
+uint64_t clmul_8x8_low_gen(uint64_t n, uint64_t m)
+{
+    uint64_t r = 0;
+
+    for (int i = 0; i < 8; ++i) {
+        uint64_t mask = (n & 0x0101010101010101ull) * 0xff;
+        r ^= m & mask;
+        m = (m << 1) & 0xfefefefefefefefeull;
+        n >>= 1;
+    }
+    return r;
+}
+
+uint64_t clmul_8x4_even_gen(uint64_t n, uint64_t m)
+{
+    uint64_t r = 0;
+
+    n &= 0x00ff00ff00ff00ffull;
+    m &= 0x00ff00ff00ff00ffull;
+
+    for (int i = 0; i < 8; ++i) {
+        uint64_t mask = (n & 0x0001000100010001ull) * 0xffff;
+        r ^= m & mask;
+        n >>= 1;
+        m <<= 1;
+    }
+    return r;
+}
+
+uint64_t clmul_8x4_odd_gen(uint64_t n, uint64_t m)
+{
+    return clmul_8x4_even_gen(n >> 8, m >> 8);
+}
+
+Int128 clmul_8x8_even_gen(Int128 n, Int128 m)
+{
+    uint64_t rl, rh;
+
+    rl = clmul_8x4_even_gen(int128_getlo(n), int128_getlo(m));
+    rh = clmul_8x4_even_gen(int128_gethi(n), int128_gethi(m));
+    return int128_make128(rl, rh);
+}
+
+Int128 clmul_8x8_odd_gen(Int128 n, Int128 m)
+{
+    uint64_t rl, rh;
+
+    rl = clmul_8x4_odd_gen(int128_getlo(n), int128_getlo(m));
+    rh = clmul_8x4_odd_gen(int128_gethi(n), int128_gethi(m));
+    return int128_make128(rl, rh);
+}
+
+static uint64_t unpack_8_to_16(uint64_t x)
+{
+    return  (x & 0x000000ff)
+         | ((x & 0x0000ff00) << 8)
+         | ((x & 0x00ff0000) << 16)
+         | ((x & 0xff000000) << 24);
+}
+
+Int128 clmul_8x8_packed_gen(uint64_t n, uint64_t m)
+{
+    uint64_t rl, rh;
+
+    rl = clmul_8x4_even_gen(unpack_8_to_16(n), unpack_8_to_16(m));
+    rh = clmul_8x4_even_gen(unpack_8_to_16(n >> 32), unpack_8_to_16(m >> 32));
+    return int128_make128(rl, rh);
+}
diff --git a/crypto/meson.build b/crypto/meson.build
index 5f03a30d34..9ac1a89802 100644
--- a/crypto/meson.build
+++ b/crypto/meson.build
@@ -48,9 +48,12 @@ if have_afalg
 endif
 crypto_ss.add(when: gnutls, if_true: files('tls-cipher-suites.c'))
 
-util_ss.add(files('sm4.c'))
-util_ss.add(files('aes.c'))
-util_ss.add(files('init.c'))
+util_ss.add(files(
+  'aes.c',
+  'clmul.c',
+  'init.c',
+  'sm4.c',
+))
 if gnutls.found()
   util_ss.add(gnutls)
 endif
-- 
2.34.1