Commit c6415a60 authored by Catalin Vasile's avatar Catalin Vasile Committed by Herbert Xu
Browse files

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: default avatarCristian Hristea <cristi.hristea@gmail.com>
Signed-off-by: default avatarHoria Geanta <horia.geanta@freescale.com>
Signed-off-by: default avatarAlex Porosanu <alexandru.porosanu@freescale.com>
Signed-off-by: default avatarCatalin Vasile <catalin.vasile@freescale.com>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent fea40451

drivers/crypto/caam/caamalg.c

+137 −1
Original line number Diff line number Diff line
@@ -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 *)&sector_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 *)&sector_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[] = {

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