From 9f00baf74e4b6f79a3a3dfab44fb7bb2e797b551 Mon Sep 17 00:00:00 2001 From: Gary R Hook Date: Tue, 30 Jul 2019 16:05:24 +0000 Subject: [PATCH] crypto: ccp - Add support for valid authsize values less than 16 AES GCM encryption allows for authsize values of 4, 8, and 12-16 bytes. Validate the requested authsize, and retain it to save in the request context. Fixes: 36cf515b9bbe2 ("crypto: ccp - Enable support for AES GCM on v5 CCPs") Cc: Signed-off-by: Gary R Hook Signed-off-by: Herbert Xu --- drivers/crypto/ccp/ccp-crypto-aes-galois.c | 14 ++++++++++++ drivers/crypto/ccp/ccp-ops.c | 26 +++++++++++++++++----- include/linux/ccp.h | 2 ++ 3 files changed, 37 insertions(+), 5 deletions(-) diff --git a/drivers/crypto/ccp/ccp-crypto-aes-galois.c b/drivers/crypto/ccp/ccp-crypto-aes-galois.c index d22631cb2bb3..02eba84028b3 100644 --- a/drivers/crypto/ccp/ccp-crypto-aes-galois.c +++ b/drivers/crypto/ccp/ccp-crypto-aes-galois.c @@ -58,6 +58,19 @@ static int ccp_aes_gcm_setkey(struct crypto_aead *tfm, const u8 *key, static int ccp_aes_gcm_setauthsize(struct crypto_aead *tfm, unsigned int authsize) { + switch (authsize) { + case 16: + case 15: + case 14: + case 13: + case 12: + case 8: + case 4: + break; + default: + return -EINVAL; + } + return 0; } @@ -104,6 +117,7 @@ static int ccp_aes_gcm_crypt(struct aead_request *req, bool encrypt) memset(&rctx->cmd, 0, sizeof(rctx->cmd)); INIT_LIST_HEAD(&rctx->cmd.entry); rctx->cmd.engine = CCP_ENGINE_AES; + rctx->cmd.u.aes.authsize = crypto_aead_authsize(tfm); rctx->cmd.u.aes.type = ctx->u.aes.type; rctx->cmd.u.aes.mode = ctx->u.aes.mode; rctx->cmd.u.aes.action = encrypt; diff --git a/drivers/crypto/ccp/ccp-ops.c b/drivers/crypto/ccp/ccp-ops.c index 59f9849c3662..ef723e2722a8 100644 --- a/drivers/crypto/ccp/ccp-ops.c +++ b/drivers/crypto/ccp/ccp-ops.c @@ -622,6 +622,7 @@ static int ccp_run_aes_gcm_cmd(struct ccp_cmd_queue *cmd_q, unsigned long long *final; unsigned int dm_offset; + unsigned int authsize; unsigned int jobid; unsigned int ilen; bool in_place = true; /* Default value */ @@ -643,6 +644,21 @@ static int ccp_run_aes_gcm_cmd(struct ccp_cmd_queue *cmd_q, if (!aes->key) /* Gotta have a key SGL */ return -EINVAL; + /* Zero defaults to 16 bytes, the maximum size */ + authsize = aes->authsize ? aes->authsize : AES_BLOCK_SIZE; + switch (authsize) { + case 16: + case 15: + case 14: + case 13: + case 12: + case 8: + case 4: + break; + default: + return -EINVAL; + } + /* First, decompose the source buffer into AAD & PT, * and the destination buffer into AAD, CT & tag, or * the input into CT & tag. @@ -657,7 +673,7 @@ static int ccp_run_aes_gcm_cmd(struct ccp_cmd_queue *cmd_q, p_tag = scatterwalk_ffwd(sg_tag, p_outp, ilen); } else { /* Input length for decryption includes tag */ - ilen = aes->src_len - AES_BLOCK_SIZE; + ilen = aes->src_len - authsize; p_tag = scatterwalk_ffwd(sg_tag, p_inp, ilen); } @@ -839,19 +855,19 @@ static int ccp_run_aes_gcm_cmd(struct ccp_cmd_queue *cmd_q, if (aes->action == CCP_AES_ACTION_ENCRYPT) { /* Put the ciphered tag after the ciphertext. */ - ccp_get_dm_area(&final_wa, 0, p_tag, 0, AES_BLOCK_SIZE); + ccp_get_dm_area(&final_wa, 0, p_tag, 0, authsize); } else { /* Does this ciphered tag match the input? */ - ret = ccp_init_dm_workarea(&tag, cmd_q, AES_BLOCK_SIZE, + ret = ccp_init_dm_workarea(&tag, cmd_q, authsize, DMA_BIDIRECTIONAL); if (ret) goto e_tag; - ret = ccp_set_dm_area(&tag, 0, p_tag, 0, AES_BLOCK_SIZE); + ret = ccp_set_dm_area(&tag, 0, p_tag, 0, authsize); if (ret) goto e_tag; ret = crypto_memneq(tag.address, final_wa.address, - AES_BLOCK_SIZE) ? -EBADMSG : 0; + authsize) ? -EBADMSG : 0; ccp_dm_free(&tag); } diff --git a/include/linux/ccp.h b/include/linux/ccp.h index 7e9c991c95e0..43ed9e77cf81 100644 --- a/include/linux/ccp.h +++ b/include/linux/ccp.h @@ -173,6 +173,8 @@ struct ccp_aes_engine { enum ccp_aes_mode mode; enum ccp_aes_action action; + u32 authsize; + struct scatterlist *key; u32 key_len; /* In bytes */