From c6415a6016bff0b547c13cadb1d5e50e9ace2be3 Mon Sep 17 00:00:00 2001 From: Catalin Vasile Date: Fri, 2 Oct 2015 13:13:18 +0300 Subject: [PATCH] crypto: caam - add support for acipher xts(aes) Add support for AES working in XEX-based Tweaked-codebook mode with ciphertext Stealing (XTS) sector index - HW limitation: CAAM device supports sector index of only 8 bytes to be used for sector index inside IV, instead of whole 16 bytes received on request. This represents 2 ^ 64 = 16,777,216 Tera of possible values for sector index. Signed-off-by: Cristian Hristea Signed-off-by: Horia Geanta Signed-off-by: Alex Porosanu Signed-off-by: Catalin Vasile Signed-off-by: Herbert Xu --- drivers/crypto/caam/caamalg.c | 138 +++++++++++++++++++++++++++++++++- 1 file changed, 137 insertions(+), 1 deletion(-) diff --git a/drivers/crypto/caam/caamalg.c b/drivers/crypto/caam/caamalg.c index ad0d1ec51dd5..ea8189f4b021 100644 --- a/drivers/crypto/caam/caamalg.c +++ b/drivers/crypto/caam/caamalg.c @@ -1705,6 +1705,126 @@ static int ablkcipher_setkey(struct crypto_ablkcipher *ablkcipher, return ret; } +static int xts_ablkcipher_setkey(struct crypto_ablkcipher *ablkcipher, + const u8 *key, unsigned int keylen) +{ + struct caam_ctx *ctx = crypto_ablkcipher_ctx(ablkcipher); + struct device *jrdev = ctx->jrdev; + u32 *key_jump_cmd, *desc; + __be64 sector_size = cpu_to_be64(512); + + if (keylen != 2 * AES_MIN_KEY_SIZE && keylen != 2 * AES_MAX_KEY_SIZE) { + crypto_ablkcipher_set_flags(ablkcipher, + CRYPTO_TFM_RES_BAD_KEY_LEN); + dev_err(jrdev, "key size mismatch\n"); + return -EINVAL; + } + + memcpy(ctx->key, key, keylen); + ctx->key_dma = dma_map_single(jrdev, ctx->key, keylen, DMA_TO_DEVICE); + if (dma_mapping_error(jrdev, ctx->key_dma)) { + dev_err(jrdev, "unable to map key i/o memory\n"); + return -ENOMEM; + } + ctx->enckeylen = keylen; + + /* xts_ablkcipher_encrypt shared descriptor */ + desc = ctx->sh_desc_enc; + init_sh_desc(desc, HDR_SHARE_SERIAL | HDR_SAVECTX); + /* Skip if already shared */ + key_jump_cmd = append_jump(desc, JUMP_JSL | JUMP_TEST_ALL | + JUMP_COND_SHRD); + + /* Load class1 keys only */ + append_key_as_imm(desc, (void *)ctx->key, ctx->enckeylen, + ctx->enckeylen, CLASS_1 | KEY_DEST_CLASS_REG); + + /* Load sector size with index 40 bytes (0x28) */ + append_cmd(desc, CMD_LOAD | IMMEDIATE | LDST_SRCDST_BYTE_CONTEXT | + LDST_CLASS_1_CCB | (0x28 << LDST_OFFSET_SHIFT) | 8); + append_data(desc, (void *)§or_size, 8); + + set_jump_tgt_here(desc, key_jump_cmd); + + /* + * create sequence for loading the sector index + * Upper 8B of IV - will be used as sector index + * Lower 8B of IV - will be discarded + */ + append_cmd(desc, CMD_SEQ_LOAD | LDST_SRCDST_BYTE_CONTEXT | + LDST_CLASS_1_CCB | (0x20 << LDST_OFFSET_SHIFT) | 8); + append_seq_fifo_load(desc, 8, FIFOLD_CLASS_SKIP); + + /* Load operation */ + append_operation(desc, ctx->class1_alg_type | OP_ALG_AS_INITFINAL | + OP_ALG_ENCRYPT); + + /* Perform operation */ + ablkcipher_append_src_dst(desc); + + ctx->sh_desc_enc_dma = dma_map_single(jrdev, desc, desc_bytes(desc), + DMA_TO_DEVICE); + if (dma_mapping_error(jrdev, ctx->sh_desc_enc_dma)) { + dev_err(jrdev, "unable to map shared descriptor\n"); + return -ENOMEM; + } +#ifdef DEBUG + print_hex_dump(KERN_ERR, + "xts ablkcipher enc shdesc@" __stringify(__LINE__) ": ", + DUMP_PREFIX_ADDRESS, 16, 4, desc, desc_bytes(desc), 1); +#endif + + /* xts_ablkcipher_decrypt shared descriptor */ + desc = ctx->sh_desc_dec; + + init_sh_desc(desc, HDR_SHARE_SERIAL | HDR_SAVECTX); + /* Skip if already shared */ + key_jump_cmd = append_jump(desc, JUMP_JSL | JUMP_TEST_ALL | + JUMP_COND_SHRD); + + /* Load class1 key only */ + append_key_as_imm(desc, (void *)ctx->key, ctx->enckeylen, + ctx->enckeylen, CLASS_1 | KEY_DEST_CLASS_REG); + + /* Load sector size with index 40 bytes (0x28) */ + append_cmd(desc, CMD_LOAD | IMMEDIATE | LDST_SRCDST_BYTE_CONTEXT | + LDST_CLASS_1_CCB | (0x28 << LDST_OFFSET_SHIFT) | 8); + append_data(desc, (void *)§or_size, 8); + + set_jump_tgt_here(desc, key_jump_cmd); + + /* + * create sequence for loading the sector index + * Upper 8B of IV - will be used as sector index + * Lower 8B of IV - will be discarded + */ + append_cmd(desc, CMD_SEQ_LOAD | LDST_SRCDST_BYTE_CONTEXT | + LDST_CLASS_1_CCB | (0x20 << LDST_OFFSET_SHIFT) | 8); + append_seq_fifo_load(desc, 8, FIFOLD_CLASS_SKIP); + + /* Load operation */ + append_dec_op1(desc, ctx->class1_alg_type); + + /* Perform operation */ + ablkcipher_append_src_dst(desc); + + ctx->sh_desc_dec_dma = dma_map_single(jrdev, desc, desc_bytes(desc), + DMA_TO_DEVICE); + if (dma_mapping_error(jrdev, ctx->sh_desc_dec_dma)) { + dma_unmap_single(jrdev, ctx->sh_desc_enc_dma, + desc_bytes(ctx->sh_desc_enc), DMA_TO_DEVICE); + dev_err(jrdev, "unable to map shared descriptor\n"); + return -ENOMEM; + } +#ifdef DEBUG + print_hex_dump(KERN_ERR, + "xts ablkcipher dec shdesc@" __stringify(__LINE__) ": ", + DUMP_PREFIX_ADDRESS, 16, 4, desc, desc_bytes(desc), 1); +#endif + + return 0; +} + /* * aead_edesc - s/w-extended aead descriptor * @assoc_nents: number of segments in associated data (SPI+Seq) scatterlist @@ -2845,7 +2965,23 @@ static struct caam_alg_template driver_algs[] = { .ivsize = CTR_RFC3686_IV_SIZE, }, .class1_alg_type = OP_ALG_ALGSEL_AES | OP_ALG_AAI_CTR_MOD128, - } + }, + { + .name = "xts(aes)", + .driver_name = "xts-aes-caam", + .blocksize = AES_BLOCK_SIZE, + .type = CRYPTO_ALG_TYPE_ABLKCIPHER, + .template_ablkcipher = { + .setkey = xts_ablkcipher_setkey, + .encrypt = ablkcipher_encrypt, + .decrypt = ablkcipher_decrypt, + .geniv = "eseqiv", + .min_keysize = 2 * AES_MIN_KEY_SIZE, + .max_keysize = 2 * AES_MAX_KEY_SIZE, + .ivsize = AES_BLOCK_SIZE, + }, + .class1_alg_type = OP_ALG_ALGSEL_AES | OP_ALG_AAI_XTS, + }, }; static struct caam_aead_alg driver_aeads[] = {