aesni: Add a CCM AEAD reusing the key schedule
authorMartin Willi <martin@revosec.ch>
Thu, 26 Mar 2015 16:43:50 +0000 (17:43 +0100)
committerMartin Willi <martin@revosec.ch>
Wed, 15 Apr 2015 09:35:27 +0000 (11:35 +0200)
src/libstrongswan/plugins/aesni/Makefile.am
src/libstrongswan/plugins/aesni/aesni_ccm.c [new file with mode: 0644]
src/libstrongswan/plugins/aesni/aesni_ccm.h [new file with mode: 0644]
src/libstrongswan/plugins/aesni/aesni_plugin.c

index 0defa0b..5411131 100644 (file)
@@ -16,6 +16,7 @@ libstrongswan_aesni_la_SOURCES = \
        aesni_key.h aesni_key.c \
        aesni_cbc.h aesni_cbc.c \
        aesni_ctr.h aesni_ctr.c \
+       aesni_ccm.h aesni_ccm.c \
        aesni_plugin.h aesni_plugin.c
 
 libstrongswan_aesni_la_LDFLAGS = -module -avoid-version
diff --git a/src/libstrongswan/plugins/aesni/aesni_ccm.c b/src/libstrongswan/plugins/aesni/aesni_ccm.c
new file mode 100644 (file)
index 0000000..aeec7bf
--- /dev/null
@@ -0,0 +1,583 @@
+/*
+ * Copyright (C) 2010-2015 Martin Willi
+ * Copyright (C) 2010-2015 revosec AG
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ */
+
+#include "aesni_ccm.h"
+#include "aesni_key.h"
+
+#include <crypto/iv/iv_gen_seq.h>
+
+#include <tmmintrin.h>
+
+#define SALT_SIZE 3
+#define IV_SIZE 8
+#define NONCE_SIZE (SALT_SIZE + IV_SIZE) /* 11 */
+#define Q_SIZE (AES_BLOCK_SIZE - NONCE_SIZE - 1) /* 4 */
+
+typedef struct private_aesni_ccm_t private_aesni_ccm_t;
+
+/**
+ * CCM en/decryption method type
+ */
+typedef void (*aesni_ccm_fn_t)(private_aesni_ccm_t*, size_t, u_char*, u_char*,
+                                                          u_char*, size_t, u_char*, u_char*);
+
+/**
+ * Private data of an aesni_ccm_t object.
+ */
+struct private_aesni_ccm_t {
+
+       /**
+        * Public aesni_ccm_t interface.
+        */
+       aesni_ccm_t public;
+
+       /**
+        * Encryption key schedule
+        */
+       aesni_key_t *key;
+
+       /**
+        * IV generator.
+        */
+       iv_gen_t *iv_gen;
+
+       /**
+        * Length of the integrity check value
+        */
+       size_t icv_size;
+
+       /**
+        * Length of the key in bytes
+        */
+       size_t key_size;
+
+       /**
+        * CCM encryption function
+        */
+       aesni_ccm_fn_t encrypt;
+
+       /**
+        * CCM decryption function
+        */
+       aesni_ccm_fn_t decrypt;
+
+       /**
+        * salt to add to nonce
+        */
+       u_char salt[SALT_SIZE];
+};
+
+/**
+ * First block with control information
+ */
+typedef struct __attribute__((packed)) {
+       BITFIELD4(u_int8_t,
+               /* size of p length field q, as q-1 */
+               q_len: 3,
+               /* size of our ICV t, as (t-2)/2 */
+               t_len: 3,
+               /* do we have associated data */
+               assoc: 1,
+               reserved: 1,
+       ) flags;
+       /* nonce value */
+       struct __attribute__((packed)) {
+               u_char salt[SALT_SIZE];
+               u_char iv[IV_SIZE];
+       } nonce;
+       /* length of plain text, q */
+       u_char q[Q_SIZE];
+} b0_t;
+
+/**
+ * Counter block
+ */
+typedef struct __attribute__((packed)) {
+       BITFIELD3(u_int8_t,
+               /* size of p length field q, as q-1 */
+               q_len: 3,
+               zero: 3,
+               reserved: 2,
+       ) flags;
+       /* nonce value */
+       struct __attribute__((packed)) {
+               u_char salt[SALT_SIZE];
+               u_char iv[IV_SIZE];
+       } nonce;
+       /* counter value */
+       u_char i[Q_SIZE];
+} ctr_t;
+
+/**
+ * Build the first block B0
+ */
+static void build_b0(private_aesni_ccm_t *this, size_t len, size_t alen,
+                                        u_char *iv, void *out)
+{
+       b0_t *block = out;
+
+       block->flags.reserved = 0;
+       block->flags.assoc = alen ? 1 : 0;
+       block->flags.t_len = (this->icv_size - 2) / 2;
+       block->flags.q_len = Q_SIZE - 1;
+       memcpy(block->nonce.salt, this->salt, SALT_SIZE);
+       memcpy(block->nonce.iv, iv, IV_SIZE);
+       htoun32(block->q, len);
+}
+
+/**
+ * Build a counter block for counter i
+ */
+static void build_ctr(private_aesni_ccm_t *this, u_int32_t i, u_char *iv,
+                                         void *out)
+{
+       ctr_t *ctr = out;
+
+       ctr->flags.reserved = 0;
+       ctr->flags.zero = 0;
+       ctr->flags.q_len = Q_SIZE - 1;
+       memcpy(ctr->nonce.salt, this->salt, SALT_SIZE);
+       memcpy(ctr->nonce.iv, iv, IV_SIZE);
+       htoun32(ctr->i, i);
+}
+
+/**
+ * Calculate the ICV for the b0 and associated data
+ */
+static __m128i icv_header(private_aesni_ccm_t *this, size_t len, u_char *iv,
+                                                 u_int16_t alen, u_char *assoc)
+{
+       __m128i b, t, c;
+       u_int i, round, blocks, rem;
+
+       build_b0(this, len, alen, iv, &b);
+       c = _mm_loadu_si128(&b);
+       c = _mm_xor_si128(c, this->key->schedule[0]);
+       for (round = 1; round < this->key->rounds; round++)
+       {
+               c = _mm_aesenc_si128(c, this->key->schedule[round]);
+       }
+       c = _mm_aesenclast_si128(c, this->key->schedule[this->key->rounds]);
+
+       if (alen)
+       {
+               blocks = (alen + sizeof(alen)) / AES_BLOCK_SIZE;
+               rem = (alen + sizeof(alen)) % AES_BLOCK_SIZE;
+               if (rem)
+               {
+                       blocks++;
+               }
+               for (i = 0; i < blocks; i++)
+               {
+                       if (i == 0)
+                       {       /* first block */
+                               memset(&b, 0, sizeof(b));
+                               htoun16(&b, alen);
+                               memcpy(((u_char*)&b) + sizeof(alen), assoc,
+                                          min(alen, sizeof(b) - sizeof(alen)));
+                               t = _mm_loadu_si128(&b);
+                       }
+                       else if (i == blocks - 1 && rem)
+                       {       /* last block with padding */
+                               memset(&b, 0, sizeof(b));
+                               memcpy(&b, ((__m128i*)(assoc - sizeof(alen))) + i, rem);
+                               t = _mm_loadu_si128(&b);
+                       }
+                       else
+                       {       /* full block */
+                               t = _mm_loadu_si128(((__m128i*)(assoc - sizeof(alen))) + i);
+                       }
+                       c = _mm_xor_si128(t, c);
+                       c = _mm_xor_si128(c, this->key->schedule[0]);
+                       for (round = 1; round < this->key->rounds; round++)
+                       {
+                               c = _mm_aesenc_si128(c, this->key->schedule[round]);
+                       }
+                       c = _mm_aesenclast_si128(c, this->key->schedule[this->key->rounds]);
+               }
+       }
+       return c;
+}
+
+/**
+ * En-/Decrypt the ICV, trim and store it
+ */
+static void crypt_icv(private_aesni_ccm_t *this, u_char *iv,
+                                         __m128i c, u_char *icv)
+{
+       __m128i b, t;
+       u_int round;
+
+       build_ctr(this, 0, iv, &b);
+
+       t = _mm_loadu_si128(&b);
+       t = _mm_xor_si128(t, this->key->schedule[0]);
+       for (round = 1; round < this->key->rounds; round++)
+       {
+               t = _mm_aesenc_si128(t, this->key->schedule[round]);
+       }
+       t = _mm_aesenclast_si128(t, this->key->schedule[this->key->rounds]);
+
+       t = _mm_xor_si128(t, c);
+
+       _mm_storeu_si128(&b, t);
+       memcpy(icv, &b, this->icv_size);
+}
+
+/**
+ * Do big-endian increment on x
+ */
+static inline __m128i increment_be(__m128i x)
+{
+       __m128i swap;
+
+       swap = _mm_set_epi8(0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15);
+
+       x = _mm_shuffle_epi8(x, swap);
+       x = _mm_add_epi64(x, _mm_set_epi32(0, 0, 0, 1));
+       x = _mm_shuffle_epi8(x, swap);
+
+       return x;
+}
+
+/**
+ * Encrypt a remaining incomplete block
+ */
+static __m128i encrypt_ccm_rem(aesni_key_t *key, u_int rem, __m128i state,
+                                                          void *in, void *out, __m128i c)
+{
+       __m128i t, b, d;
+       u_int round;
+
+       memset(&b, 0, sizeof(b));
+       memcpy(&b, in, rem);
+       d = _mm_loadu_si128(&b);
+
+       c = _mm_xor_si128(d, c);
+       c = _mm_xor_si128(c, key->schedule[0]);
+       t = _mm_xor_si128(state, key->schedule[0]);
+       for (round = 1; round < key->rounds; round++)
+       {
+               c = _mm_aesenc_si128(c, key->schedule[round]);
+               t = _mm_aesenc_si128(t, key->schedule[round]);
+       }
+       c = _mm_aesenclast_si128(c, key->schedule[key->rounds]);
+       t = _mm_aesenclast_si128(t, key->schedule[key->rounds]);
+
+       t = _mm_xor_si128(t, d);
+       _mm_storeu_si128(&b, t);
+
+       memcpy(out, &b, rem);
+
+       return c;
+}
+
+/**
+ * Decrypt a remaining incomplete block
+ */
+static __m128i decrypt_ccm_rem(aesni_key_t *key, u_int rem, __m128i state,
+                                                          void *in, void *out, __m128i c)
+{
+       __m128i t, b, d;
+       u_int round;
+
+       memset(&b, 0, sizeof(b));
+       memcpy(&b, in, rem);
+       d = _mm_loadu_si128(&b);
+
+       t = _mm_xor_si128(state, key->schedule[0]);
+       for (round = 1; round < key->rounds; round++)
+       {
+               t = _mm_aesenc_si128(t, key->schedule[round]);
+       }
+       t = _mm_aesenclast_si128(t, key->schedule[key->rounds]);
+       t = _mm_xor_si128(t, d);
+       _mm_storeu_si128(&b, t);
+
+       memset((u_char*)&b + rem, 0, sizeof(b) - rem);
+       t = _mm_loadu_si128(&b);
+       c = _mm_xor_si128(t, c);
+       c = _mm_xor_si128(c, key->schedule[0]);
+       for (round = 1; round < key->rounds; round++)
+       {
+               c = _mm_aesenc_si128(c, key->schedule[round]);
+       }
+       c = _mm_aesenclast_si128(c, key->schedule[key->rounds]);
+
+       memcpy(out, &b, rem);
+
+       return c;
+}
+
+/**
+ * Generic CCM encryption/ICV generation
+ */
+static void encrypt_ccm(private_aesni_ccm_t *this,
+                                               size_t len, u_char *in, u_char *out, u_char *iv,
+                                               size_t alen, u_char *assoc, u_char *icv)
+{
+       __m128i d, t, c, b, state, *bi, *bo;
+       u_int round, blocks, rem, i;
+
+       c = icv_header(this, len, iv, alen, assoc);
+       build_ctr(this, 1, iv, &b);
+       state = _mm_load_si128(&b);
+       blocks = len / AES_BLOCK_SIZE;
+       rem = len % AES_BLOCK_SIZE;
+       bi = (__m128i*)in;
+       bo = (__m128i*)out;
+
+       for (i = 0; i < blocks; i++)
+       {
+               d = _mm_loadu_si128(bi + i);
+
+               c = _mm_xor_si128(d, c);
+               c = _mm_xor_si128(c, this->key->schedule[0]);
+               t = _mm_xor_si128(state, this->key->schedule[0]);
+               for (round = 1; round < this->key->rounds; round++)
+               {
+                       c = _mm_aesenc_si128(c, this->key->schedule[round]);
+                       t = _mm_aesenc_si128(t, this->key->schedule[round]);
+               }
+               c = _mm_aesenclast_si128(c, this->key->schedule[this->key->rounds]);
+               t = _mm_aesenclast_si128(t, this->key->schedule[this->key->rounds]);
+
+               t = _mm_xor_si128(t, d);
+               _mm_storeu_si128(bo + i, t);
+
+               state = increment_be(state);
+       }
+
+       if (rem)
+       {
+               c = encrypt_ccm_rem(this->key, rem, state, bi + blocks, bo + blocks, c);
+       }
+       crypt_icv(this, iv, c, icv);
+}
+
+/**
+ * Generic CCM decryption/ICV generation
+ */
+static void decrypt_ccm(private_aesni_ccm_t *this,
+                                               size_t len, u_char *in, u_char *out, u_char *iv,
+                                               size_t alen, u_char *assoc, u_char *icv)
+{
+       __m128i d, t, c, b, state, *bi, *bo;
+       u_int round, blocks, rem, i;
+
+       c = icv_header(this, len, iv, alen, assoc);
+       build_ctr(this, 1, iv, &b);
+       state = _mm_load_si128(&b);
+       blocks = len / AES_BLOCK_SIZE;
+       rem = len % AES_BLOCK_SIZE;
+       bi = (__m128i*)in;
+       bo = (__m128i*)out;
+
+       for (i = 0; i < blocks; i++)
+       {
+               d = _mm_loadu_si128(bi + i);
+
+               t = _mm_xor_si128(state, this->key->schedule[0]);
+               for (round = 1; round < this->key->rounds; round++)
+               {
+                       t = _mm_aesenc_si128(t, this->key->schedule[round]);
+               }
+               t = _mm_aesenclast_si128(t, this->key->schedule[this->key->rounds]);
+               t = _mm_xor_si128(t, d);
+               _mm_storeu_si128(bo + i, t);
+
+               c = _mm_xor_si128(t, c);
+               c = _mm_xor_si128(c, this->key->schedule[0]);
+               for (round = 1; round < this->key->rounds; round++)
+               {
+                       c = _mm_aesenc_si128(c, this->key->schedule[round]);
+               }
+               c = _mm_aesenclast_si128(c, this->key->schedule[this->key->rounds]);
+
+               state = increment_be(state);
+       }
+
+       if (rem)
+       {
+               c = decrypt_ccm_rem(this->key, rem, state, bi + blocks, bo + blocks, c);
+       }
+       crypt_icv(this, iv, c, icv);
+}
+
+METHOD(aead_t, encrypt, bool,
+       private_aesni_ccm_t *this, chunk_t plain, chunk_t assoc, chunk_t iv,
+       chunk_t *encr)
+{
+       u_char *out;
+
+       if (!this->key || iv.len != IV_SIZE)
+       {
+               return FALSE;
+       }
+       out = plain.ptr;
+       if (encr)
+       {
+               *encr = chunk_alloc(plain.len + this->icv_size);
+               out = encr->ptr;
+       }
+       this->encrypt(this, plain.len, plain.ptr, out, iv.ptr,
+                                 assoc.len, assoc.ptr, out + plain.len);
+       return TRUE;
+}
+
+METHOD(aead_t, decrypt, bool,
+       private_aesni_ccm_t *this, chunk_t encr, chunk_t assoc, chunk_t iv,
+       chunk_t *plain)
+{
+       u_char *out, icv[this->icv_size];
+
+       if (!this->key || iv.len != IV_SIZE || encr.len < this->icv_size)
+       {
+               return FALSE;
+       }
+       encr.len -= this->icv_size;
+       out = encr.ptr;
+       if (plain)
+       {
+               *plain = chunk_alloc(encr.len);
+               out = plain->ptr;
+       }
+
+       this->decrypt(this, encr.len, encr.ptr, out, iv.ptr,
+                                 assoc.len, assoc.ptr, icv);
+       return memeq_const(icv, encr.ptr + encr.len, this->icv_size);
+}
+
+METHOD(aead_t, get_block_size, size_t,
+       private_aesni_ccm_t *this)
+{
+       return 1;
+}
+
+METHOD(aead_t, get_icv_size, size_t,
+       private_aesni_ccm_t *this)
+{
+       return this->icv_size;
+}
+
+METHOD(aead_t, get_iv_size, size_t,
+       private_aesni_ccm_t *this)
+{
+       return IV_SIZE;
+}
+
+METHOD(aead_t, get_iv_gen, iv_gen_t*,
+       private_aesni_ccm_t *this)
+{
+       return this->iv_gen;
+}
+
+METHOD(aead_t, get_key_size, size_t,
+       private_aesni_ccm_t *this)
+{
+       return this->key_size + SALT_SIZE;
+}
+
+METHOD(aead_t, set_key, bool,
+       private_aesni_ccm_t *this, chunk_t key)
+{
+       if (key.len != this->key_size + SALT_SIZE)
+       {
+               return FALSE;
+       }
+
+       memcpy(this->salt, key.ptr + key.len - SALT_SIZE, SALT_SIZE);
+       key.len -= SALT_SIZE;
+
+       DESTROY_IF(this->key);
+       this->key = aesni_key_create(TRUE, key);
+       return TRUE;
+}
+
+METHOD(aead_t, destroy, void,
+       private_aesni_ccm_t *this)
+{
+       DESTROY_IF(this->key);
+       this->iv_gen->destroy(this->iv_gen);
+       free(this);
+}
+
+/**
+ * See header
+ */
+aesni_ccm_t *aesni_ccm_create(encryption_algorithm_t algo,
+                                                         size_t key_size, size_t salt_size)
+{
+       private_aesni_ccm_t *this;
+       size_t icv_size;
+
+       switch (key_size)
+       {
+               case 0:
+                       key_size = 16;
+                       break;
+               case 16:
+               case 24:
+               case 32:
+                       break;
+               default:
+                       return NULL;
+       }
+       if (salt_size && salt_size != SALT_SIZE)
+       {
+               /* currently not supported */
+               return NULL;
+       }
+       switch (algo)
+       {
+               case ENCR_AES_CCM_ICV8:
+                       algo = ENCR_AES_CBC;
+                       icv_size = 8;
+                       break;
+               case ENCR_AES_CCM_ICV12:
+                       algo = ENCR_AES_CBC;
+                       icv_size = 12;
+                       break;
+               case ENCR_AES_CCM_ICV16:
+                       algo = ENCR_AES_CBC;
+                       icv_size = 16;
+                       break;
+               default:
+                       return NULL;
+       }
+
+       INIT(this,
+               .public = {
+                       .aead = {
+                               .encrypt = _encrypt,
+                               .decrypt = _decrypt,
+                               .get_block_size = _get_block_size,
+                               .get_icv_size = _get_icv_size,
+                               .get_iv_size = _get_iv_size,
+                               .get_iv_gen = _get_iv_gen,
+                               .get_key_size = _get_key_size,
+                               .set_key = _set_key,
+                               .destroy = _destroy,
+                       },
+               },
+               .key_size = key_size,
+               .iv_gen = iv_gen_seq_create(),
+               .icv_size = icv_size,
+               .encrypt = encrypt_ccm,
+               .decrypt = decrypt_ccm,
+       );
+
+       return &this->public;
+}
diff --git a/src/libstrongswan/plugins/aesni/aesni_ccm.h b/src/libstrongswan/plugins/aesni/aesni_ccm.h
new file mode 100644 (file)
index 0000000..69612b5
--- /dev/null
@@ -0,0 +1,50 @@
+/*
+ * Copyright (C) 2015 Martin Willi
+ * Copyright (C) 2015 revosec AG
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ */
+
+/**
+ * @defgroup aesni_ccm aesni_ccm
+ * @{ @ingroup aesni
+ */
+
+#ifndef AESNI_CCM_H_
+#define AESNI_CCM_H_
+
+#include <library.h>
+
+typedef struct aesni_ccm_t aesni_ccm_t;
+
+/**
+ * CCM mode AEAD using AES-NI
+ */
+struct aesni_ccm_t {
+
+       /**
+        * Implements aead_t interface
+        */
+       aead_t aead;
+};
+
+/**
+ * Create a aesni_ccm instance.
+ *
+ * @param algo                 encryption algorithm, ENCR_AES_CCM*
+ * @param key_size             AES key size, in bytes
+ * @param salt_size            size of salt value
+ * @return                             AES-CCM AEAD, NULL if not supported
+ */
+aesni_ccm_t *aesni_ccm_create(encryption_algorithm_t algo,
+                                                         size_t key_size, size_t salt_size);
+
+#endif /** AESNI_CCM_H_ @}*/
index 697392d..764ecba 100644 (file)
@@ -16,6 +16,7 @@
 #include "aesni_plugin.h"
 #include "aesni_cbc.h"
 #include "aesni_ctr.h"
+#include "aesni_ccm.h"
 
 #include <stdio.h>
 
@@ -55,6 +56,16 @@ METHOD(plugin_t, get_features, int,
                        PLUGIN_PROVIDE(CRYPTER, ENCR_AES_CTR, 16),
                        PLUGIN_PROVIDE(CRYPTER, ENCR_AES_CTR, 24),
                        PLUGIN_PROVIDE(CRYPTER, ENCR_AES_CTR, 32),
+               PLUGIN_REGISTER(AEAD, aesni_ccm_create),
+                       PLUGIN_PROVIDE(AEAD, ENCR_AES_CCM_ICV8,  16),
+                       PLUGIN_PROVIDE(AEAD, ENCR_AES_CCM_ICV12, 16),
+                       PLUGIN_PROVIDE(AEAD, ENCR_AES_CCM_ICV16, 16),
+                       PLUGIN_PROVIDE(AEAD, ENCR_AES_CCM_ICV8,  24),
+                       PLUGIN_PROVIDE(AEAD, ENCR_AES_CCM_ICV12, 24),
+                       PLUGIN_PROVIDE(AEAD, ENCR_AES_CCM_ICV16, 24),
+                       PLUGIN_PROVIDE(AEAD, ENCR_AES_CCM_ICV8,  32),
+                       PLUGIN_PROVIDE(AEAD, ENCR_AES_CCM_ICV12, 32),
+                       PLUGIN_PROVIDE(AEAD, ENCR_AES_CCM_ICV16, 32),
        };
 
        *features = f;