From e9b4913a5f944b23d6109c44b6f3fc6e092e30ce Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Horia=20Geant=C4=83?= Date: Wed, 31 Jul 2019 16:08:11 +0300 Subject: crypto: caam - fix MDHA key derivation for certain user key lengths MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Fuzz testing uncovered an issue when |user key| > |derived key|. Derived key generation has to be fixed in two cases: 1. Era >= 6 (DKP is available) DKP cannot be used with immediate input key if |user key| > |derived key|, since the resulting descriptor (after DKP execution) would be invalid - having a few bytes from user key left in descriptor buffer as incorrect opcodes. Fix DKP usage both in standalone hmac and in authenc algorithms. For authenc the logic is simplified, by always storing both virtual and dma key addresses. 2. Era < 6 The same case (|user key| > |derived key|) fails when DKP is not available. Make sure gen_split_key() dma maps max(|user key|, |derived key|), since this is an in-place (bidirectional) operation. Signed-off-by: Horia Geantă Reviewed-by: Iuliana Prodan Signed-off-by: Herbert Xu --- drivers/crypto/caam/caamalg.c | 42 ++++++++++++------------------------------ 1 file changed, 12 insertions(+), 30 deletions(-) (limited to 'drivers/crypto/caam/caamalg.c') diff --git a/drivers/crypto/caam/caamalg.c b/drivers/crypto/caam/caamalg.c index 21e30ded365a..947ba8ef487a 100644 --- a/drivers/crypto/caam/caamalg.c +++ b/drivers/crypto/caam/caamalg.c @@ -205,6 +205,18 @@ static int aead_set_sh_desc(struct crypto_aead *aead) ctx->cdata.keylen - CTR_RFC3686_NONCE_SIZE); } + /* + * In case |user key| > |derived key|, using DKP + * would result in invalid opcodes (last bytes of user key) in + * the resulting descriptor. Use DKP instead => both + * virtual and dma key addresses are needed. + */ + ctx->adata.key_virt = ctx->key; + ctx->adata.key_dma = ctx->key_dma; + + ctx->cdata.key_virt = ctx->key + ctx->adata.keylen_pad; + ctx->cdata.key_dma = ctx->key_dma + ctx->adata.keylen_pad; + data_len[0] = ctx->adata.keylen_pad; data_len[1] = ctx->cdata.keylen; @@ -221,16 +233,6 @@ static int aead_set_sh_desc(struct crypto_aead *aead) ARRAY_SIZE(data_len)) < 0) return -EINVAL; - if (inl_mask & 1) - ctx->adata.key_virt = ctx->key; - else - ctx->adata.key_dma = ctx->key_dma; - - if (inl_mask & 2) - ctx->cdata.key_virt = ctx->key + ctx->adata.keylen_pad; - else - ctx->cdata.key_dma = ctx->key_dma + ctx->adata.keylen_pad; - ctx->adata.key_inline = !!(inl_mask & 1); ctx->cdata.key_inline = !!(inl_mask & 2); @@ -253,16 +255,6 @@ skip_enc: ARRAY_SIZE(data_len)) < 0) return -EINVAL; - if (inl_mask & 1) - ctx->adata.key_virt = ctx->key; - else - ctx->adata.key_dma = ctx->key_dma; - - if (inl_mask & 2) - ctx->cdata.key_virt = ctx->key + ctx->adata.keylen_pad; - else - ctx->cdata.key_dma = ctx->key_dma + ctx->adata.keylen_pad; - ctx->adata.key_inline = !!(inl_mask & 1); ctx->cdata.key_inline = !!(inl_mask & 2); @@ -287,16 +279,6 @@ skip_enc: ARRAY_SIZE(data_len)) < 0) return -EINVAL; - if (inl_mask & 1) - ctx->adata.key_virt = ctx->key; - else - ctx->adata.key_dma = ctx->key_dma; - - if (inl_mask & 2) - ctx->cdata.key_virt = ctx->key + ctx->adata.keylen_pad; - else - ctx->cdata.key_dma = ctx->key_dma + ctx->adata.keylen_pad; - ctx->adata.key_inline = !!(inl_mask & 1); ctx->cdata.key_inline = !!(inl_mask & 2); -- cgit v1.2.3