From: Andrei Botila <andrei.botila@xxxxxxx> A hardware limitation exists for CAAM until Era 9 which restricts the accelerator to IVs with only 8 bytes. When CAAM has a lower era a fallback is necessary to process 16 bytes IV. Fixes: c6415a6016bf ("crypto: caam - add support for acipher xts(aes)") Cc: <stable@xxxxxxxxxxxxxxx> # v4.4+ Signed-off-by: Andrei Botila <andrei.botila@xxxxxxx> --- drivers/crypto/caam/Kconfig | 1 + drivers/crypto/caam/caamalg.c | 72 +++++++++++++++++++++++++++++++---- 2 files changed, 66 insertions(+), 7 deletions(-) diff --git a/drivers/crypto/caam/Kconfig b/drivers/crypto/caam/Kconfig index bc35aa0ec07a..dfeaad8dfe81 100644 --- a/drivers/crypto/caam/Kconfig +++ b/drivers/crypto/caam/Kconfig @@ -101,6 +101,7 @@ config CRYPTO_DEV_FSL_CAAM_CRYPTO_API select CRYPTO_AUTHENC select CRYPTO_SKCIPHER select CRYPTO_LIB_DES + select CRYPTO_XTS help Selecting this will offload crypto for users of the scatterlist crypto API (such as the linux native IPSec diff --git a/drivers/crypto/caam/caamalg.c b/drivers/crypto/caam/caamalg.c index 91feda5b63f6..adb2c05a8bde 100644 --- a/drivers/crypto/caam/caamalg.c +++ b/drivers/crypto/caam/caamalg.c @@ -57,6 +57,7 @@ #include "key_gen.h" #include "caamalg_desc.h" #include <crypto/engine.h> +#include <asm/unaligned.h> /* * crypto alg @@ -114,10 +115,12 @@ struct caam_ctx { struct alginfo adata; struct alginfo cdata; unsigned int authsize; + struct crypto_skcipher *fallback; }; struct caam_skcipher_req_ctx { struct skcipher_edesc *edesc; + struct skcipher_request fallback_req; }; struct caam_aead_req_ctx { @@ -830,12 +833,17 @@ static int xts_skcipher_setkey(struct crypto_skcipher *skcipher, const u8 *key, struct caam_ctx *ctx = crypto_skcipher_ctx(skcipher); struct device *jrdev = ctx->jrdev; u32 *desc; + int err; if (keylen != 2 * AES_MIN_KEY_SIZE && keylen != 2 * AES_MAX_KEY_SIZE) { dev_dbg(jrdev, "key size mismatch\n"); return -EINVAL; } + err = crypto_skcipher_setkey(ctx->fallback, key, keylen); + if (err) + return err; + ctx->cdata.keylen = keylen; ctx->cdata.key_virt = key; ctx->cdata.key_inline = true; @@ -1755,6 +1763,14 @@ static int skcipher_do_one_req(struct crypto_engine *engine, void *areq) return ret; } +static inline bool xts_skcipher_ivsize(struct skcipher_request *req) +{ + struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req); + unsigned int ivsize = crypto_skcipher_ivsize(skcipher); + + return !!get_unaligned((u64 *)(req->iv + (ivsize / 2))); +} + static inline int skcipher_crypt(struct skcipher_request *req, bool encrypt) { struct skcipher_edesc *edesc; @@ -1768,6 +1784,21 @@ static inline int skcipher_crypt(struct skcipher_request *req, bool encrypt) if (!req->cryptlen) return 0; + if (ctx->fallback && xts_skcipher_ivsize(req)) { + struct caam_skcipher_req_ctx *rctx = skcipher_request_ctx(req); + + skcipher_request_set_tfm(&rctx->fallback_req, ctx->fallback); + skcipher_request_set_callback(&rctx->fallback_req, + req->base.flags, + req->base.complete, + req->base.data); + skcipher_request_set_crypt(&rctx->fallback_req, req->src, + req->dst, req->cryptlen, req->iv); + + return encrypt ? crypto_skcipher_encrypt(&rctx->fallback_req) : + crypto_skcipher_decrypt(&rctx->fallback_req); + } + /* allocate extended descriptor */ edesc = skcipher_edesc_alloc(req, DESC_JOB_IO_LEN * CAAM_CMD_SZ); if (IS_ERR(edesc)) @@ -1905,6 +1936,7 @@ static struct caam_skcipher_alg driver_algs[] = { .base = { .cra_name = "xts(aes)", .cra_driver_name = "xts-aes-caam", + .cra_flags = CRYPTO_ALG_NEED_FALLBACK, .cra_blocksize = AES_BLOCK_SIZE, }, .setkey = xts_skcipher_setkey, @@ -3344,13 +3376,35 @@ static int caam_cra_init(struct crypto_skcipher *tfm) struct caam_skcipher_alg *caam_alg = container_of(alg, typeof(*caam_alg), skcipher); struct caam_ctx *ctx = crypto_skcipher_ctx(tfm); - - crypto_skcipher_set_reqsize(tfm, sizeof(struct caam_skcipher_req_ctx)); + u32 alg_aai = caam_alg->caam.class1_alg_type & OP_ALG_AAI_MASK; + int ret = 0; ctx->enginectx.op.do_one_request = skcipher_do_one_req; - return caam_init_common(crypto_skcipher_ctx(tfm), &caam_alg->caam, - false); + if (alg_aai == OP_ALG_AAI_XTS) { + const char *tfm_name = crypto_tfm_alg_name(&tfm->base); + struct crypto_skcipher *fallback; + + fallback = crypto_alloc_skcipher(tfm_name, 0, + CRYPTO_ALG_NEED_FALLBACK); + if (IS_ERR(fallback)) { + dev_err(ctx->jrdev, "Failed to allocate %s fallback: %ld\n", + tfm_name, PTR_ERR(fallback)); + return PTR_ERR(fallback); + } + + ctx->fallback = fallback; + crypto_skcipher_set_reqsize(tfm, sizeof(struct caam_skcipher_req_ctx) + + crypto_skcipher_reqsize(fallback)); + } else { + crypto_skcipher_set_reqsize(tfm, sizeof(struct caam_skcipher_req_ctx)); + } + + ret = caam_init_common(ctx, &caam_alg->caam, false); + if (ret && ctx->fallback) + crypto_free_skcipher(ctx->fallback); + + return ret; } static int caam_aead_init(struct crypto_aead *tfm) @@ -3378,7 +3432,11 @@ static void caam_exit_common(struct caam_ctx *ctx) static void caam_cra_exit(struct crypto_skcipher *tfm) { - caam_exit_common(crypto_skcipher_ctx(tfm)); + struct caam_ctx *ctx = crypto_skcipher_ctx(tfm); + + if (ctx->fallback) + crypto_free_skcipher(ctx->fallback); + caam_exit_common(ctx); } static void caam_aead_exit(struct crypto_aead *tfm) @@ -3412,8 +3470,8 @@ static void caam_skcipher_alg_init(struct caam_skcipher_alg *t_alg) alg->base.cra_module = THIS_MODULE; alg->base.cra_priority = CAAM_CRA_PRIORITY; alg->base.cra_ctxsize = sizeof(struct caam_ctx); - alg->base.cra_flags = CRYPTO_ALG_ASYNC | CRYPTO_ALG_ALLOCATES_MEMORY | - CRYPTO_ALG_KERN_DRIVER_ONLY; + alg->base.cra_flags |= (CRYPTO_ALG_ASYNC | CRYPTO_ALG_ALLOCATES_MEMORY | + CRYPTO_ALG_KERN_DRIVER_ONLY); alg->init = caam_cra_init; alg->exit = caam_cra_exit; -- 2.17.1