Messages in this thread | | | Date | Wed, 8 Jul 2015 12:18:38 +0800 | From | Herbert Xu <> | Subject | Re: [PATCH v2 6/7] crypto: omap-aes: Add support for GCM mode |
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On Tue, Jul 07, 2015 at 09:01:48PM +0530, Lokesh Vutla wrote: > > +static int omap_aes_gcm_copy_buffers(struct omap_aes_dev *dd, > + struct aead_request *req) > +{ > + void *buf_in; > + int pages, alen, clen, cryptlen, nsg; > + struct crypto_aead *aead = crypto_aead_reqtfm(req); > + unsigned int authlen = crypto_aead_authsize(aead); > + u32 dec = !(dd->flags & FLAGS_ENCRYPT); > + struct scatterlist *input, *assoc, tmp[2]; > + > + alen = ALIGN(req->assoclen, AES_BLOCK_SIZE); > + cryptlen = req->cryptlen - (dec * authlen); > + clen = ALIGN(cryptlen, AES_BLOCK_SIZE); > + > + dd->sgs_copied = 0; > + > + nsg = !!(req->assoclen && req->cryptlen); > + > + assoc = &req->src[0]; > + sg_init_table(dd->in_sgl, nsg + 1); > + if (req->assoclen) { > + if (omap_aes_check_aligned(assoc, req->assoclen)) { > + dd->sgs_copied |= AES_ASSOC_DATA_COPIED; > + pages = get_order(alen); > + buf_in = (void *)__get_free_pages(GFP_ATOMIC, pages); > + if (!buf_in) { > + pr_err("Couldn't allocate for unaligncases.\n"); > + return -1; > + } > + > + scatterwalk_map_and_copy(buf_in, assoc, 0, > + req->assoclen, 0); > + memset(buf_in + req->assoclen, 0, alen - req->assoclen); > + } else { > + buf_in = sg_virt(req->assoc);
req->assoc is now obsolete. Did you test this code?
> +static int do_encrypt_iv(struct aead_request *req, u32 *tag) > +{ > + struct scatterlist iv_sg; > + struct ablkcipher_request *ablk_req; > + struct crypto_ablkcipher *tfm; > + struct tcrypt_result result; > + struct omap_aes_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req)); > + int ret = 0; > + > + tfm = crypto_alloc_ablkcipher("ctr(aes)", 0, 0);
Ugh, you cannot allocate crypto transforms in the data path. You should allocate it in init instead. Also using ctr(aes) is overkill. Just use aes and do the xor by hand.
> +static int omap_aes_gcm_crypt(struct aead_request *req, unsigned long mode) > +{ > + struct omap_aes_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req)); > + struct omap_aes_reqctx *rctx = aead_request_ctx(req); > + struct crypto_aead *aead = crypto_aead_reqtfm(req); > + unsigned int authlen = crypto_aead_authsize(aead); > + struct omap_aes_dev *dd; > + __be32 counter = cpu_to_be32(1); > + int err; > + > + memset(ctx->auth_tag, 0, sizeof(ctx->auth_tag));
The ctx is shared memory and you must not write to it as multiple requests can be called on the same tfm. Use rctx instead.
> + memcpy(req->iv + 12, &counter, 4);
The IV is only 12 bytes long so you're corrupting memory here. You should use rctx here too.
> + if (req->assoclen + req->cryptlen == 0) { > + scatterwalk_map_and_copy(ctx->auth_tag, req->dst, 0, authlen, > + 1); > + return 0; > + }
How can this be right? Did you enable the selftest?
Cheers, -- Email: Herbert Xu <herbert@gondor.apana.org.au> Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
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