Squashed 'lib/mbedtls/external/mbedtls/' content from commit 2ca6c285a0dd

git-subtree-dir: lib/mbedtls/external/mbedtls
git-subtree-split: 2ca6c285a0dd3f33982dd57299012dacab1ff206
diff --git a/library/aesce.c b/library/aesce.c
new file mode 100644
index 0000000..6a9e0a1
--- /dev/null
+++ b/library/aesce.c
@@ -0,0 +1,618 @@
+/*
+ *  Armv8-A Cryptographic Extension support functions for Aarch64
+ *
+ *  Copyright The Mbed TLS Contributors
+ *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
+ */
+
+#if defined(__clang__) &&  (__clang_major__ >= 4)
+
+/* Ideally, we would simply use MBEDTLS_ARCH_IS_ARMV8_A in the following #if,
+ * but that is defined by build_info.h, and we need this block to happen first. */
+#if defined(__ARM_ARCH)
+#if __ARM_ARCH >= 8
+#define MBEDTLS_AESCE_ARCH_IS_ARMV8_A
+#endif
+#endif
+
+#if defined(MBEDTLS_AESCE_ARCH_IS_ARMV8_A) && !defined(__ARM_FEATURE_CRYPTO)
+/* TODO: Re-consider above after https://reviews.llvm.org/D131064 merged.
+ *
+ * The intrinsic declaration are guarded by predefined ACLE macros in clang:
+ * these are normally only enabled by the -march option on the command line.
+ * By defining the macros ourselves we gain access to those declarations without
+ * requiring -march on the command line.
+ *
+ * `arm_neon.h` is included by common.h, so we put these defines
+ * at the top of this file, before any includes.
+ */
+#define __ARM_FEATURE_CRYPTO 1
+/* See: https://arm-software.github.io/acle/main/acle.html#cryptographic-extensions
+ *
+ * `__ARM_FEATURE_CRYPTO` is deprecated, but we need to continue to specify it
+ * for older compilers.
+ */
+#define __ARM_FEATURE_AES    1
+#define MBEDTLS_ENABLE_ARM_CRYPTO_EXTENSIONS_COMPILER_FLAG
+#endif
+
+#endif /* defined(__clang__) &&  (__clang_major__ >= 4) */
+
+#include <string.h>
+#include "common.h"
+
+#if defined(MBEDTLS_AESCE_C)
+
+#include "aesce.h"
+
+#if defined(MBEDTLS_AESCE_HAVE_CODE)
+
+/* Compiler version checks. */
+#if defined(__clang__)
+#   if defined(MBEDTLS_ARCH_IS_ARM32) && (__clang_major__ < 11)
+#       error "Minimum version of Clang for MBEDTLS_AESCE_C on 32-bit Arm or Thumb is 11.0."
+#   elif defined(MBEDTLS_ARCH_IS_ARM64) && (__clang_major__ < 4)
+#       error "Minimum version of Clang for MBEDTLS_AESCE_C on aarch64 is 4.0."
+#   endif
+#elif defined(__GNUC__)
+#   if __GNUC__ < 6
+#       error "Minimum version of GCC for MBEDTLS_AESCE_C is 6.0."
+#   endif
+#elif defined(_MSC_VER)
+/* TODO: We haven't verified MSVC from 1920 to 1928. If someone verified that,
+ *       please update this and document of `MBEDTLS_AESCE_C` in
+ *       `mbedtls_config.h`. */
+#   if _MSC_VER < 1929
+#       error "Minimum version of MSVC for MBEDTLS_AESCE_C is 2019 version 16.11.2."
+#   endif
+#elif defined(__ARMCC_VERSION)
+#    if defined(MBEDTLS_ARCH_IS_ARM32) && (__ARMCC_VERSION < 6200002)
+/* TODO: We haven't verified armclang for 32-bit Arm/Thumb prior to 6.20.
+ * If someone verified that, please update this and document of
+ * `MBEDTLS_AESCE_C` in `mbedtls_config.h`. */
+#         error "Minimum version of armclang for MBEDTLS_AESCE_C on 32-bit Arm is 6.20."
+#    elif defined(MBEDTLS_ARCH_IS_ARM64) && (__ARMCC_VERSION < 6060000)
+#         error "Minimum version of armclang for MBEDTLS_AESCE_C on aarch64 is 6.6."
+#    endif
+#endif
+
+#if !(defined(__ARM_FEATURE_CRYPTO) || defined(__ARM_FEATURE_AES)) || \
+    defined(MBEDTLS_ENABLE_ARM_CRYPTO_EXTENSIONS_COMPILER_FLAG)
+#   if defined(__ARMCOMPILER_VERSION)
+#       if __ARMCOMPILER_VERSION <= 6090000
+#           error "Must use minimum -march=armv8-a+crypto for MBEDTLS_AESCE_C"
+#       else
+#           pragma clang attribute push (__attribute__((target("aes"))), apply_to=function)
+#           define MBEDTLS_POP_TARGET_PRAGMA
+#       endif
+#   elif defined(__clang__)
+#       pragma clang attribute push (__attribute__((target("aes"))), apply_to=function)
+#       define MBEDTLS_POP_TARGET_PRAGMA
+#   elif defined(__GNUC__)
+#       pragma GCC push_options
+#       pragma GCC target ("+crypto")
+#       define MBEDTLS_POP_TARGET_PRAGMA
+#   elif defined(_MSC_VER)
+#       error "Required feature(__ARM_FEATURE_AES) is not enabled."
+#   endif
+#endif /* !(__ARM_FEATURE_CRYPTO || __ARM_FEATURE_AES) ||
+          MBEDTLS_ENABLE_ARM_CRYPTO_EXTENSIONS_COMPILER_FLAG */
+
+#if defined(__linux__) && !defined(MBEDTLS_AES_USE_HARDWARE_ONLY)
+
+#include <sys/auxv.h>
+#if !defined(HWCAP_NEON)
+#define HWCAP_NEON  (1 << 12)
+#endif
+#if !defined(HWCAP2_AES)
+#define HWCAP2_AES  (1 << 0)
+#endif
+#if !defined(HWCAP_AES)
+#define HWCAP_AES   (1 << 3)
+#endif
+#if !defined(HWCAP_ASIMD)
+#define HWCAP_ASIMD (1 << 1)
+#endif
+
+signed char mbedtls_aesce_has_support_result = -1;
+
+#if !defined(MBEDTLS_AES_USE_HARDWARE_ONLY)
+/*
+ * AES instruction support detection routine
+ */
+int mbedtls_aesce_has_support_impl(void)
+{
+    /* To avoid many calls to getauxval, cache the result. This is
+     * thread-safe, because we store the result in a char so cannot
+     * be vulnerable to non-atomic updates.
+     * It is possible that we could end up setting result more than
+     * once, but that is harmless.
+     */
+    if (mbedtls_aesce_has_support_result == -1) {
+#if defined(MBEDTLS_ARCH_IS_ARM32)
+        unsigned long auxval  = getauxval(AT_HWCAP);
+        unsigned long auxval2 = getauxval(AT_HWCAP2);
+        if (((auxval  & HWCAP_NEON) == HWCAP_NEON) &&
+            ((auxval2 & HWCAP2_AES) == HWCAP2_AES)) {
+            mbedtls_aesce_has_support_result = 1;
+        } else {
+            mbedtls_aesce_has_support_result = 0;
+        }
+#else
+        unsigned long auxval = getauxval(AT_HWCAP);
+        if ((auxval & (HWCAP_ASIMD | HWCAP_AES)) ==
+            (HWCAP_ASIMD | HWCAP_AES)) {
+            mbedtls_aesce_has_support_result = 1;
+        } else {
+            mbedtls_aesce_has_support_result = 0;
+        }
+#endif
+    }
+    return mbedtls_aesce_has_support_result;
+}
+#endif
+
+#endif /* defined(__linux__) && !defined(MBEDTLS_AES_USE_HARDWARE_ONLY) */
+
+/* Single round of AESCE encryption */
+#define AESCE_ENCRYPT_ROUND                   \
+    block = vaeseq_u8(block, vld1q_u8(keys)); \
+    block = vaesmcq_u8(block);                \
+    keys += 16
+/* Two rounds of AESCE encryption */
+#define AESCE_ENCRYPT_ROUND_X2        AESCE_ENCRYPT_ROUND; AESCE_ENCRYPT_ROUND
+
+MBEDTLS_OPTIMIZE_FOR_PERFORMANCE
+static uint8x16_t aesce_encrypt_block(uint8x16_t block,
+                                      unsigned char *keys,
+                                      int rounds)
+{
+    /* 10, 12 or 14 rounds. Unroll loop. */
+    if (rounds == 10) {
+        goto rounds_10;
+    }
+    if (rounds == 12) {
+        goto rounds_12;
+    }
+    AESCE_ENCRYPT_ROUND_X2;
+rounds_12:
+    AESCE_ENCRYPT_ROUND_X2;
+rounds_10:
+    AESCE_ENCRYPT_ROUND_X2;
+    AESCE_ENCRYPT_ROUND_X2;
+    AESCE_ENCRYPT_ROUND_X2;
+    AESCE_ENCRYPT_ROUND_X2;
+    AESCE_ENCRYPT_ROUND;
+
+    /* AES AddRoundKey for the previous round.
+     * SubBytes, ShiftRows for the final round.  */
+    block = vaeseq_u8(block, vld1q_u8(keys));
+    keys += 16;
+
+    /* Final round: no MixColumns */
+
+    /* Final AddRoundKey */
+    block = veorq_u8(block, vld1q_u8(keys));
+
+    return block;
+}
+
+/* Single round of AESCE decryption
+ *
+ * AES AddRoundKey, SubBytes, ShiftRows
+ *
+ *      block = vaesdq_u8(block, vld1q_u8(keys));
+ *
+ * AES inverse MixColumns for the next round.
+ *
+ * This means that we switch the order of the inverse AddRoundKey and
+ * inverse MixColumns operations. We have to do this as AddRoundKey is
+ * done in an atomic instruction together with the inverses of SubBytes
+ * and ShiftRows.
+ *
+ * It works because MixColumns is a linear operation over GF(2^8) and
+ * AddRoundKey is an exclusive or, which is equivalent to addition over
+ * GF(2^8). (The inverse of MixColumns needs to be applied to the
+ * affected round keys separately which has been done when the
+ * decryption round keys were calculated.)
+ *
+ *      block = vaesimcq_u8(block);
+ */
+#define AESCE_DECRYPT_ROUND                   \
+    block = vaesdq_u8(block, vld1q_u8(keys)); \
+    block = vaesimcq_u8(block);               \
+    keys += 16
+/* Two rounds of AESCE decryption */
+#define AESCE_DECRYPT_ROUND_X2        AESCE_DECRYPT_ROUND; AESCE_DECRYPT_ROUND
+
+#if !defined(MBEDTLS_BLOCK_CIPHER_NO_DECRYPT)
+static uint8x16_t aesce_decrypt_block(uint8x16_t block,
+                                      unsigned char *keys,
+                                      int rounds)
+{
+    /* 10, 12 or 14 rounds. Unroll loop. */
+    if (rounds == 10) {
+        goto rounds_10;
+    }
+    if (rounds == 12) {
+        goto rounds_12;
+    }
+    AESCE_DECRYPT_ROUND_X2;
+rounds_12:
+    AESCE_DECRYPT_ROUND_X2;
+rounds_10:
+    AESCE_DECRYPT_ROUND_X2;
+    AESCE_DECRYPT_ROUND_X2;
+    AESCE_DECRYPT_ROUND_X2;
+    AESCE_DECRYPT_ROUND_X2;
+    AESCE_DECRYPT_ROUND;
+
+    /* The inverses of AES AddRoundKey, SubBytes, ShiftRows finishing up the
+     * last full round. */
+    block = vaesdq_u8(block, vld1q_u8(keys));
+    keys += 16;
+
+    /* Inverse AddRoundKey for inverting the initial round key addition. */
+    block = veorq_u8(block, vld1q_u8(keys));
+
+    return block;
+}
+#endif
+
+/*
+ * AES-ECB block en(de)cryption
+ */
+int mbedtls_aesce_crypt_ecb(mbedtls_aes_context *ctx,
+                            int mode,
+                            const unsigned char input[16],
+                            unsigned char output[16])
+{
+    uint8x16_t block = vld1q_u8(&input[0]);
+    unsigned char *keys = (unsigned char *) (ctx->buf + ctx->rk_offset);
+
+#if !defined(MBEDTLS_BLOCK_CIPHER_NO_DECRYPT)
+    if (mode == MBEDTLS_AES_DECRYPT) {
+        block = aesce_decrypt_block(block, keys, ctx->nr);
+    } else
+#else
+    (void) mode;
+#endif
+    {
+        block = aesce_encrypt_block(block, keys, ctx->nr);
+    }
+    vst1q_u8(&output[0], block);
+
+    return 0;
+}
+
+/*
+ * Compute decryption round keys from encryption round keys
+ */
+#if !defined(MBEDTLS_BLOCK_CIPHER_NO_DECRYPT)
+void mbedtls_aesce_inverse_key(unsigned char *invkey,
+                               const unsigned char *fwdkey,
+                               int nr)
+{
+    int i, j;
+    j = nr;
+    vst1q_u8(invkey, vld1q_u8(fwdkey + j * 16));
+    for (i = 1, j--; j > 0; i++, j--) {
+        vst1q_u8(invkey + i * 16,
+                 vaesimcq_u8(vld1q_u8(fwdkey + j * 16)));
+    }
+    vst1q_u8(invkey + i * 16, vld1q_u8(fwdkey + j * 16));
+
+}
+#endif
+
+static inline uint32_t aes_rot_word(uint32_t word)
+{
+    return (word << (32 - 8)) | (word >> 8);
+}
+
+static inline uint32_t aes_sub_word(uint32_t in)
+{
+    uint8x16_t v = vreinterpretq_u8_u32(vdupq_n_u32(in));
+    uint8x16_t zero = vdupq_n_u8(0);
+
+    /* vaeseq_u8 does both SubBytes and ShiftRows. Taking the first row yields
+     * the correct result as ShiftRows doesn't change the first row. */
+    v = vaeseq_u8(zero, v);
+    return vgetq_lane_u32(vreinterpretq_u32_u8(v), 0);
+}
+
+/*
+ * Key expansion function
+ */
+static void aesce_setkey_enc(unsigned char *rk,
+                             const unsigned char *key,
+                             const size_t key_bit_length)
+{
+    static uint8_t const rcon[] = { 0x01, 0x02, 0x04, 0x08, 0x10,
+                                    0x20, 0x40, 0x80, 0x1b, 0x36 };
+    /* See https://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.197.pdf
+     *   - Section 5, Nr = Nk + 6
+     *   - Section 5.2, the length of round keys is Nb*(Nr+1)
+     */
+    const size_t key_len_in_words = key_bit_length / 32;    /* Nk */
+    const size_t round_key_len_in_words = 4;                /* Nb */
+    const size_t rounds_needed = key_len_in_words + 6;      /* Nr */
+    const size_t round_keys_len_in_words =
+        round_key_len_in_words * (rounds_needed + 1);       /* Nb*(Nr+1) */
+    const uint32_t *rko_end = (uint32_t *) rk + round_keys_len_in_words;
+
+    memcpy(rk, key, key_len_in_words * 4);
+
+    for (uint32_t *rki = (uint32_t *) rk;
+         rki + key_len_in_words < rko_end;
+         rki += key_len_in_words) {
+
+        size_t iteration = (size_t) (rki - (uint32_t *) rk) / key_len_in_words;
+        uint32_t *rko;
+        rko = rki + key_len_in_words;
+        rko[0] = aes_rot_word(aes_sub_word(rki[key_len_in_words - 1]));
+        rko[0] ^= rcon[iteration] ^ rki[0];
+        rko[1] = rko[0] ^ rki[1];
+        rko[2] = rko[1] ^ rki[2];
+        rko[3] = rko[2] ^ rki[3];
+        if (rko + key_len_in_words > rko_end) {
+            /* Do not write overflow words.*/
+            continue;
+        }
+#if !defined(MBEDTLS_AES_ONLY_128_BIT_KEY_LENGTH)
+        switch (key_bit_length) {
+            case 128:
+                break;
+            case 192:
+                rko[4] = rko[3] ^ rki[4];
+                rko[5] = rko[4] ^ rki[5];
+                break;
+            case 256:
+                rko[4] = aes_sub_word(rko[3]) ^ rki[4];
+                rko[5] = rko[4] ^ rki[5];
+                rko[6] = rko[5] ^ rki[6];
+                rko[7] = rko[6] ^ rki[7];
+                break;
+        }
+#endif /* !MBEDTLS_AES_ONLY_128_BIT_KEY_LENGTH */
+    }
+}
+
+/*
+ * Key expansion, wrapper
+ */
+int mbedtls_aesce_setkey_enc(unsigned char *rk,
+                             const unsigned char *key,
+                             size_t bits)
+{
+    switch (bits) {
+        case 128:
+        case 192:
+        case 256:
+            aesce_setkey_enc(rk, key, bits);
+            break;
+        default:
+            return MBEDTLS_ERR_AES_INVALID_KEY_LENGTH;
+    }
+
+    return 0;
+}
+
+#if defined(MBEDTLS_GCM_C)
+
+#if defined(MBEDTLS_ARCH_IS_ARM32)
+
+#if defined(__clang__)
+/* On clang for A32/T32, work around some missing intrinsics and types which are listed in
+ * [ACLE](https://arm-software.github.io/acle/neon_intrinsics/advsimd.html#polynomial-1)
+ * These are only required for GCM.
+ */
+#define vreinterpretq_u64_p64(a) ((uint64x2_t) a)
+
+typedef uint8x16_t poly128_t;
+
+static inline poly128_t vmull_p64(poly64_t a, poly64_t b)
+{
+    poly128_t r;
+    asm ("vmull.p64 %[r], %[a], %[b]" : [r] "=w" (r) : [a] "w" (a), [b] "w" (b) :);
+    return r;
+}
+
+/* This is set to cause some more missing intrinsics to be defined below */
+#define COMMON_MISSING_INTRINSICS
+
+static inline poly128_t vmull_high_p64(poly64x2_t a, poly64x2_t b)
+{
+    return vmull_p64((poly64_t) (vget_high_u64((uint64x2_t) a)),
+                     (poly64_t) (vget_high_u64((uint64x2_t) b)));
+}
+
+#endif /* defined(__clang__) */
+
+static inline uint8x16_t vrbitq_u8(uint8x16_t x)
+{
+    /* There is no vrbitq_u8 instruction in A32/T32, so provide
+     * an equivalent non-Neon implementation. Reverse bit order in each
+     * byte with 4x rbit, rev. */
+    asm ("ldm  %[p], { r2-r5 } \n\t"
+         "rbit r2, r2          \n\t"
+         "rev  r2, r2          \n\t"
+         "rbit r3, r3          \n\t"
+         "rev  r3, r3          \n\t"
+         "rbit r4, r4          \n\t"
+         "rev  r4, r4          \n\t"
+         "rbit r5, r5          \n\t"
+         "rev  r5, r5          \n\t"
+         "stm  %[p], { r2-r5 } \n\t"
+         :
+         /* Output: 16 bytes of memory pointed to by &x */
+         "+m" (*(uint8_t(*)[16]) &x)
+         :
+         [p] "r" (&x)
+         :
+         "r2", "r3", "r4", "r5"
+         );
+    return x;
+}
+
+#endif /* defined(MBEDTLS_ARCH_IS_ARM32) */
+
+#if defined(MBEDTLS_COMPILER_IS_GCC) && __GNUC__ == 5
+/* Some intrinsics are not available for GCC 5.X. */
+#define COMMON_MISSING_INTRINSICS
+#endif /* MBEDTLS_COMPILER_IS_GCC && __GNUC__ == 5 */
+
+
+#if defined(COMMON_MISSING_INTRINSICS)
+
+/* Missing intrinsics common to both GCC 5, and Clang on 32-bit */
+
+#define vreinterpretq_p64_u8(a)  ((poly64x2_t) a)
+#define vreinterpretq_u8_p128(a) ((uint8x16_t) a)
+
+static inline poly64x1_t vget_low_p64(poly64x2_t a)
+{
+    uint64x1_t r = vget_low_u64(vreinterpretq_u64_p64(a));
+    return (poly64x1_t) r;
+
+}
+
+#endif /* COMMON_MISSING_INTRINSICS */
+
+/* vmull_p64/vmull_high_p64 wrappers.
+ *
+ * Older compilers miss some intrinsic functions for `poly*_t`. We use
+ * uint8x16_t and uint8x16x3_t as input/output parameters.
+ */
+#if defined(MBEDTLS_COMPILER_IS_GCC)
+/* GCC reports incompatible type error without cast. GCC think poly64_t and
+ * poly64x1_t are different, that is different with MSVC and Clang. */
+#define MBEDTLS_VMULL_P64(a, b) vmull_p64((poly64_t) a, (poly64_t) b)
+#else
+/* MSVC reports `error C2440: 'type cast'` with cast. Clang does not report
+ * error with/without cast. And I think poly64_t and poly64x1_t are same, no
+ * cast for clang also. */
+#define MBEDTLS_VMULL_P64(a, b) vmull_p64(a, b)
+#endif /* MBEDTLS_COMPILER_IS_GCC */
+
+static inline uint8x16_t pmull_low(uint8x16_t a, uint8x16_t b)
+{
+
+    return vreinterpretq_u8_p128(
+        MBEDTLS_VMULL_P64(
+            (poly64_t) vget_low_p64(vreinterpretq_p64_u8(a)),
+            (poly64_t) vget_low_p64(vreinterpretq_p64_u8(b))
+            ));
+}
+
+static inline uint8x16_t pmull_high(uint8x16_t a, uint8x16_t b)
+{
+    return vreinterpretq_u8_p128(
+        vmull_high_p64(vreinterpretq_p64_u8(a),
+                       vreinterpretq_p64_u8(b)));
+}
+
+/* GHASH does 128b polynomial multiplication on block in GF(2^128) defined by
+ * `x^128 + x^7 + x^2 + x + 1`.
+ *
+ * Arm64 only has 64b->128b polynomial multipliers, we need to do 4 64b
+ * multiplies to generate a 128b.
+ *
+ * `poly_mult_128` executes polynomial multiplication and outputs 256b that
+ * represented by 3 128b due to code size optimization.
+ *
+ * Output layout:
+ * |            |             |             |
+ * |------------|-------------|-------------|
+ * | ret.val[0] | h3:h2:00:00 | high   128b |
+ * | ret.val[1] |   :m2:m1:00 | middle 128b |
+ * | ret.val[2] |   :  :l1:l0 | low    128b |
+ */
+static inline uint8x16x3_t poly_mult_128(uint8x16_t a, uint8x16_t b)
+{
+    uint8x16x3_t ret;
+    uint8x16_t h, m, l; /* retval high/middle/low */
+    uint8x16_t c, d, e;
+
+    h = pmull_high(a, b);                       /* h3:h2:00:00 = a1*b1 */
+    l = pmull_low(a, b);                        /*   :  :l1:l0 = a0*b0 */
+    c = vextq_u8(b, b, 8);                      /*      :c1:c0 = b0:b1 */
+    d = pmull_high(a, c);                       /*   :d2:d1:00 = a1*b0 */
+    e = pmull_low(a, c);                        /*   :e2:e1:00 = a0*b1 */
+    m = veorq_u8(d, e);                         /*   :m2:m1:00 = d + e */
+
+    ret.val[0] = h;
+    ret.val[1] = m;
+    ret.val[2] = l;
+    return ret;
+}
+
+/*
+ * Modulo reduction.
+ *
+ * See: https://www.researchgate.net/publication/285612706_Implementing_GCM_on_ARMv8
+ *
+ * Section 4.3
+ *
+ * Modular reduction is slightly more complex. Write the GCM modulus as f(z) =
+ * z^128 +r(z), where r(z) = z^7+z^2+z+ 1. The well known approach is to
+ * consider that z^128 ≡r(z) (mod z^128 +r(z)), allowing us to write the 256-bit
+ * operand to be reduced as a(z) = h(z)z^128 +l(z)≡h(z)r(z) + l(z). That is, we
+ * simply multiply the higher part of the operand by r(z) and add it to l(z). If
+ * the result is still larger than 128 bits, we reduce again.
+ */
+static inline uint8x16_t poly_mult_reduce(uint8x16x3_t input)
+{
+    uint8x16_t const ZERO = vdupq_n_u8(0);
+
+    uint64x2_t r = vreinterpretq_u64_u8(vdupq_n_u8(0x87));
+#if defined(__GNUC__)
+    /* use 'asm' as an optimisation barrier to prevent loading MODULO from
+     * memory. It is for GNUC compatible compilers.
+     */
+    asm volatile ("" : "+w" (r));
+#endif
+    uint8x16_t const MODULO = vreinterpretq_u8_u64(vshrq_n_u64(r, 64 - 8));
+    uint8x16_t h, m, l; /* input high/middle/low 128b */
+    uint8x16_t c, d, e, f, g, n, o;
+    h = input.val[0];            /* h3:h2:00:00                          */
+    m = input.val[1];            /*   :m2:m1:00                          */
+    l = input.val[2];            /*   :  :l1:l0                          */
+    c = pmull_high(h, MODULO);   /*   :c2:c1:00 = reduction of h3        */
+    d = pmull_low(h, MODULO);    /*   :  :d1:d0 = reduction of h2        */
+    e = veorq_u8(c, m);          /*   :e2:e1:00 = m2:m1:00 + c2:c1:00    */
+    f = pmull_high(e, MODULO);   /*   :  :f1:f0 = reduction of e2        */
+    g = vextq_u8(ZERO, e, 8);    /*   :  :g1:00 = e1:00                  */
+    n = veorq_u8(d, l);          /*   :  :n1:n0 = d1:d0 + l1:l0          */
+    o = veorq_u8(n, f);          /*       o1:o0 = f1:f0 + n1:n0          */
+    return veorq_u8(o, g);       /*             = o1:o0 + g1:00          */
+}
+
+/*
+ * GCM multiplication: c = a times b in GF(2^128)
+ */
+void mbedtls_aesce_gcm_mult(unsigned char c[16],
+                            const unsigned char a[16],
+                            const unsigned char b[16])
+{
+    uint8x16_t va, vb, vc;
+    va = vrbitq_u8(vld1q_u8(&a[0]));
+    vb = vrbitq_u8(vld1q_u8(&b[0]));
+    vc = vrbitq_u8(poly_mult_reduce(poly_mult_128(va, vb)));
+    vst1q_u8(&c[0], vc);
+}
+
+#endif /* MBEDTLS_GCM_C */
+
+#if defined(MBEDTLS_POP_TARGET_PRAGMA)
+#if defined(__clang__)
+#pragma clang attribute pop
+#elif defined(__GNUC__)
+#pragma GCC pop_options
+#endif
+#undef MBEDTLS_POP_TARGET_PRAGMA
+#endif
+
+#endif /* MBEDTLS_AESCE_HAVE_CODE */
+
+#endif /* MBEDTLS_AESCE_C */