From 9d3b5030bc1e44fe88d0f2879d52ef1e375a63be Mon Sep 17 00:00:00 2001 From: Fabien DESSENNE Date: Wed, 7 Feb 2018 14:08:54 +0100 Subject: crypto: stm32/cryp - add aes gcm / ccm support Add AEAD cipher algorithms for aes gcm and ccm. Signed-off-by: Fabien Dessenne Signed-off-by: Herbert Xu --- drivers/crypto/stm32/stm32-cryp.c | 931 ++++++++++++++++++++++++++++++++++++-- 1 file changed, 902 insertions(+), 29 deletions(-) (limited to 'drivers/crypto/stm32') diff --git a/drivers/crypto/stm32/stm32-cryp.c b/drivers/crypto/stm32/stm32-cryp.c index 0f0e2ba56a5a..6a1fe983ed13 100644 --- a/drivers/crypto/stm32/stm32-cryp.c +++ b/drivers/crypto/stm32/stm32-cryp.c @@ -17,6 +17,7 @@ #include #include #include +#include #define DRIVER_NAME "stm32-cryp" @@ -29,8 +30,12 @@ #define FLG_ECB BIT(4) #define FLG_CBC BIT(5) #define FLG_CTR BIT(6) +#define FLG_GCM BIT(7) +#define FLG_CCM BIT(8) /* Mode mask = bits [15..0] */ #define FLG_MODE_MASK GENMASK(15, 0) +/* Bit [31..16] status */ +#define FLG_CCM_PADDED_WA BIT(16) /* Registers */ #define CRYP_CR 0x00000000 @@ -53,6 +58,8 @@ #define CRYP_IV0RR 0x00000044 #define CRYP_IV1LR 0x00000048 #define CRYP_IV1RR 0x0000004C +#define CRYP_CSGCMCCM0R 0x00000050 +#define CRYP_CSGCM0R 0x00000070 /* Registers values */ #define CR_DEC_NOT_ENC 0x00000004 @@ -64,6 +71,8 @@ #define CR_AES_CBC 0x00000028 #define CR_AES_CTR 0x00000030 #define CR_AES_KP 0x00000038 +#define CR_AES_GCM 0x00080000 +#define CR_AES_CCM 0x00080008 #define CR_AES_UNKNOWN 0xFFFFFFFF #define CR_ALGO_MASK 0x00080038 #define CR_DATA32 0x00000000 @@ -75,6 +84,12 @@ #define CR_KEY256 0x00000200 #define CR_FFLUSH 0x00004000 #define CR_CRYPEN 0x00008000 +#define CR_PH_INIT 0x00000000 +#define CR_PH_HEADER 0x00010000 +#define CR_PH_PAYLOAD 0x00020000 +#define CR_PH_FINAL 0x00030000 +#define CR_PH_MASK 0x00030000 +#define CR_NBPBL_SHIFT 20 #define SR_BUSY 0x00000010 #define SR_OFNE 0x00000004 @@ -87,9 +102,15 @@ /* Misc */ #define AES_BLOCK_32 (AES_BLOCK_SIZE / sizeof(u32)) +#define GCM_CTR_INIT 2 #define _walked_in (cryp->in_walk.offset - cryp->in_sg->offset) #define _walked_out (cryp->out_walk.offset - cryp->out_sg->offset) +struct stm32_cryp_caps { + bool swap_final; + bool padding_wa; +}; + struct stm32_cryp_ctx { struct crypto_engine_ctx enginectx; struct stm32_cryp *cryp; @@ -109,13 +130,16 @@ struct stm32_cryp { struct clk *clk; unsigned long flags; u32 irq_status; + const struct stm32_cryp_caps *caps; struct stm32_cryp_ctx *ctx; struct crypto_engine *engine; - struct mutex lock; /* protects req */ + struct mutex lock; /* protects req / areq */ struct ablkcipher_request *req; + struct aead_request *areq; + size_t authsize; size_t hw_blocksize; size_t total_in; @@ -138,6 +162,7 @@ struct stm32_cryp { struct scatter_walk out_walk; u32 last_ctr[4]; + u32 gcm_ctr; }; struct stm32_cryp_list { @@ -180,6 +205,16 @@ static inline bool is_ctr(struct stm32_cryp *cryp) return cryp->flags & FLG_CTR; } +static inline bool is_gcm(struct stm32_cryp *cryp) +{ + return cryp->flags & FLG_GCM; +} + +static inline bool is_ccm(struct stm32_cryp *cryp) +{ + return cryp->flags & FLG_CCM; +} + static inline bool is_encrypt(struct stm32_cryp *cryp) { return cryp->flags & FLG_ENCRYPT; @@ -208,6 +243,24 @@ static inline int stm32_cryp_wait_busy(struct stm32_cryp *cryp) !(status & SR_BUSY), 10, 100000); } +static inline int stm32_cryp_wait_enable(struct stm32_cryp *cryp) +{ + u32 status; + + return readl_relaxed_poll_timeout(cryp->regs + CRYP_CR, status, + !(status & CR_CRYPEN), 10, 100000); +} + +static inline int stm32_cryp_wait_output(struct stm32_cryp *cryp) +{ + u32 status; + + return readl_relaxed_poll_timeout(cryp->regs + CRYP_SR, status, + status & SR_OFNE, 10, 100000); +} + +static int stm32_cryp_read_auth_tag(struct stm32_cryp *cryp); + static struct stm32_cryp *stm32_cryp_find_dev(struct stm32_cryp_ctx *ctx) { struct stm32_cryp *tmp, *cryp = NULL; @@ -366,6 +419,12 @@ static u32 stm32_cryp_get_hw_mode(struct stm32_cryp *cryp) if (is_aes(cryp) && is_ctr(cryp)) return CR_AES_CTR; + if (is_aes(cryp) && is_gcm(cryp)) + return CR_AES_GCM; + + if (is_aes(cryp) && is_ccm(cryp)) + return CR_AES_CCM; + if (is_des(cryp) && is_ecb(cryp)) return CR_DES_ECB; @@ -382,6 +441,79 @@ static u32 stm32_cryp_get_hw_mode(struct stm32_cryp *cryp) return CR_AES_UNKNOWN; } +static unsigned int stm32_cryp_get_input_text_len(struct stm32_cryp *cryp) +{ + return is_encrypt(cryp) ? cryp->areq->cryptlen : + cryp->areq->cryptlen - cryp->authsize; +} + +static int stm32_cryp_gcm_init(struct stm32_cryp *cryp, u32 cfg) +{ + int ret; + u32 iv[4]; + + /* Phase 1 : init */ + memcpy(iv, cryp->areq->iv, 12); + iv[3] = cpu_to_be32(GCM_CTR_INIT); + cryp->gcm_ctr = GCM_CTR_INIT; + stm32_cryp_hw_write_iv(cryp, iv); + + stm32_cryp_write(cryp, CRYP_CR, cfg | CR_PH_INIT | CR_CRYPEN); + + /* Wait for end of processing */ + ret = stm32_cryp_wait_enable(cryp); + if (ret) + dev_err(cryp->dev, "Timeout (gcm init)\n"); + + return ret; +} + +static int stm32_cryp_ccm_init(struct stm32_cryp *cryp, u32 cfg) +{ + int ret; + u8 iv[AES_BLOCK_SIZE], b0[AES_BLOCK_SIZE]; + u32 *d; + unsigned int i, textlen; + + /* Phase 1 : init. Firstly set the CTR value to 1 (not 0) */ + memcpy(iv, cryp->areq->iv, AES_BLOCK_SIZE); + memset(iv + AES_BLOCK_SIZE - 1 - iv[0], 0, iv[0] + 1); + iv[AES_BLOCK_SIZE - 1] = 1; + stm32_cryp_hw_write_iv(cryp, (u32 *)iv); + + /* Build B0 */ + memcpy(b0, iv, AES_BLOCK_SIZE); + + b0[0] |= (8 * ((cryp->authsize - 2) / 2)); + + if (cryp->areq->assoclen) + b0[0] |= 0x40; + + textlen = stm32_cryp_get_input_text_len(cryp); + + b0[AES_BLOCK_SIZE - 2] = textlen >> 8; + b0[AES_BLOCK_SIZE - 1] = textlen & 0xFF; + + /* Enable HW */ + stm32_cryp_write(cryp, CRYP_CR, cfg | CR_PH_INIT | CR_CRYPEN); + + /* Write B0 */ + d = (u32 *)b0; + + for (i = 0; i < AES_BLOCK_32; i++) { + if (!cryp->caps->padding_wa) + *d = cpu_to_be32(*d); + stm32_cryp_write(cryp, CRYP_DIN, *d++); + } + + /* Wait for end of processing */ + ret = stm32_cryp_wait_enable(cryp); + if (ret) + dev_err(cryp->dev, "Timeout (ccm init)\n"); + + return ret; +} + static int stm32_cryp_hw_init(struct stm32_cryp *cryp) { int ret; @@ -437,6 +569,29 @@ static int stm32_cryp_hw_init(struct stm32_cryp *cryp) stm32_cryp_write(cryp, CRYP_CR, cfg); switch (hw_mode) { + case CR_AES_GCM: + case CR_AES_CCM: + /* Phase 1 : init */ + if (hw_mode == CR_AES_CCM) + ret = stm32_cryp_ccm_init(cryp, cfg); + else + ret = stm32_cryp_gcm_init(cryp, cfg); + + if (ret) + return ret; + + /* Phase 2 : header (authenticated data) */ + if (cryp->areq->assoclen) { + cfg |= CR_PH_HEADER; + } else if (stm32_cryp_get_input_text_len(cryp)) { + cfg |= CR_PH_PAYLOAD; + stm32_cryp_write(cryp, CRYP_CR, cfg); + } else { + cfg |= CR_PH_INIT; + } + + break; + case CR_DES_CBC: case CR_TDES_CBC: case CR_AES_CBC: @@ -453,12 +608,16 @@ static int stm32_cryp_hw_init(struct stm32_cryp *cryp) stm32_cryp_write(cryp, CRYP_CR, cfg); + cryp->flags &= ~FLG_CCM_PADDED_WA; + return 0; } -static void stm32_cryp_finish_req(struct stm32_cryp *cryp) +static void stm32_cryp_finish_req(struct stm32_cryp *cryp, int err) { - int err = 0; + if (!err && (is_gcm(cryp) || is_ccm(cryp))) + /* Phase 4 : output tag */ + err = stm32_cryp_read_auth_tag(cryp); if (cryp->sgs_copied) { void *buf_in, *buf_out; @@ -479,8 +638,14 @@ static void stm32_cryp_finish_req(struct stm32_cryp *cryp) free_pages((unsigned long)buf_out, pages); } - crypto_finalize_ablkcipher_request(cryp->engine, cryp->req, err); - cryp->req = NULL; + if (is_gcm(cryp) || is_ccm(cryp)) { + crypto_finalize_aead_request(cryp->engine, cryp->areq, err); + cryp->areq = NULL; + } else { + crypto_finalize_ablkcipher_request(cryp->engine, cryp->req, + err); + cryp->req = NULL; + } memset(cryp->ctx->key, 0, cryp->ctx->keylen); @@ -511,6 +676,23 @@ static int stm32_cryp_cra_init(struct crypto_tfm *tfm) return 0; } +static int stm32_cryp_aead_one_req(struct crypto_engine *engine, void *areq); +static int stm32_cryp_prepare_aead_req(struct crypto_engine *engine, + void *areq); + +static int stm32_cryp_aes_aead_init(struct crypto_aead *tfm) +{ + struct stm32_cryp_ctx *ctx = crypto_aead_ctx(tfm); + + tfm->reqsize = sizeof(struct stm32_cryp_reqctx); + + ctx->enginectx.op.do_one_request = stm32_cryp_aead_one_req; + ctx->enginectx.op.prepare_request = stm32_cryp_prepare_aead_req; + ctx->enginectx.op.unprepare_request = NULL; + + return 0; +} + static int stm32_cryp_crypt(struct ablkcipher_request *req, unsigned long mode) { struct stm32_cryp_ctx *ctx = crypto_ablkcipher_ctx( @@ -526,6 +708,20 @@ static int stm32_cryp_crypt(struct ablkcipher_request *req, unsigned long mode) return crypto_transfer_ablkcipher_request_to_engine(cryp->engine, req); } +static int stm32_cryp_aead_crypt(struct aead_request *req, unsigned long mode) +{ + struct stm32_cryp_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req)); + struct stm32_cryp_reqctx *rctx = aead_request_ctx(req); + struct stm32_cryp *cryp = stm32_cryp_find_dev(ctx); + + if (!cryp) + return -ENODEV; + + rctx->mode = mode; + + return crypto_transfer_aead_request_to_engine(cryp->engine, req); +} + static int stm32_cryp_setkey(struct crypto_ablkcipher *tfm, const u8 *key, unsigned int keylen) { @@ -565,6 +761,46 @@ static int stm32_cryp_tdes_setkey(struct crypto_ablkcipher *tfm, const u8 *key, return stm32_cryp_setkey(tfm, key, keylen); } +static int stm32_cryp_aes_aead_setkey(struct crypto_aead *tfm, const u8 *key, + unsigned int keylen) +{ + struct stm32_cryp_ctx *ctx = crypto_aead_ctx(tfm); + + if (keylen != AES_KEYSIZE_128 && keylen != AES_KEYSIZE_192 && + keylen != AES_KEYSIZE_256) + return -EINVAL; + + memcpy(ctx->key, key, keylen); + ctx->keylen = keylen; + + return 0; +} + +static int stm32_cryp_aes_gcm_setauthsize(struct crypto_aead *tfm, + unsigned int authsize) +{ + return authsize == AES_BLOCK_SIZE ? 0 : -EINVAL; +} + +static int stm32_cryp_aes_ccm_setauthsize(struct crypto_aead *tfm, + unsigned int authsize) +{ + switch (authsize) { + case 4: + case 6: + case 8: + case 10: + case 12: + case 14: + case 16: + break; + default: + return -EINVAL; + } + + return 0; +} + static int stm32_cryp_aes_ecb_encrypt(struct ablkcipher_request *req) { return stm32_cryp_crypt(req, FLG_AES | FLG_ECB | FLG_ENCRYPT); @@ -595,6 +831,26 @@ static int stm32_cryp_aes_ctr_decrypt(struct ablkcipher_request *req) return stm32_cryp_crypt(req, FLG_AES | FLG_CTR); } +static int stm32_cryp_aes_gcm_encrypt(struct aead_request *req) +{ + return stm32_cryp_aead_crypt(req, FLG_AES | FLG_GCM | FLG_ENCRYPT); +} + +static int stm32_cryp_aes_gcm_decrypt(struct aead_request *req) +{ + return stm32_cryp_aead_crypt(req, FLG_AES | FLG_GCM); +} + +static int stm32_cryp_aes_ccm_encrypt(struct aead_request *req) +{ + return stm32_cryp_aead_crypt(req, FLG_AES | FLG_CCM | FLG_ENCRYPT); +} + +static int stm32_cryp_aes_ccm_decrypt(struct aead_request *req) +{ + return stm32_cryp_aead_crypt(req, FLG_AES | FLG_CCM); +} + static int stm32_cryp_des_ecb_encrypt(struct ablkcipher_request *req) { return stm32_cryp_crypt(req, FLG_DES | FLG_ECB | FLG_ENCRYPT); @@ -635,18 +891,19 @@ static int stm32_cryp_tdes_cbc_decrypt(struct ablkcipher_request *req) return stm32_cryp_crypt(req, FLG_TDES | FLG_CBC); } -static int stm32_cryp_prepare_req(struct crypto_engine *engine, - struct ablkcipher_request *req) +static int stm32_cryp_prepare_req(struct ablkcipher_request *req, + struct aead_request *areq) { struct stm32_cryp_ctx *ctx; struct stm32_cryp *cryp; struct stm32_cryp_reqctx *rctx; int ret; - if (!req) + if (!req && !areq) return -EINVAL; - ctx = crypto_ablkcipher_ctx(crypto_ablkcipher_reqtfm(req)); + ctx = req ? crypto_ablkcipher_ctx(crypto_ablkcipher_reqtfm(req)) : + crypto_aead_ctx(crypto_aead_reqtfm(areq)); cryp = ctx->cryp; @@ -655,7 +912,7 @@ static int stm32_cryp_prepare_req(struct crypto_engine *engine, mutex_lock(&cryp->lock); - rctx = ablkcipher_request_ctx(req); + rctx = req ? ablkcipher_request_ctx(req) : aead_request_ctx(areq); rctx->mode &= FLG_MODE_MASK; ctx->cryp = cryp; @@ -664,15 +921,48 @@ static int stm32_cryp_prepare_req(struct crypto_engine *engine, cryp->hw_blocksize = is_aes(cryp) ? AES_BLOCK_SIZE : DES_BLOCK_SIZE; cryp->ctx = ctx; - cryp->req = req; - cryp->total_in = req->nbytes; - cryp->total_out = cryp->total_in; + if (req) { + cryp->req = req; + cryp->total_in = req->nbytes; + cryp->total_out = cryp->total_in; + } else { + /* + * Length of input and output data: + * Encryption case: + * INPUT = AssocData || PlainText + * <- assoclen -> <- cryptlen -> + * <------- total_in -----------> + * + * OUTPUT = AssocData || CipherText || AuthTag + * <- assoclen -> <- cryptlen -> <- authsize -> + * <---------------- total_out -----------------> + * + * Decryption case: + * INPUT = AssocData || CipherText || AuthTag + * <- assoclen -> <--------- cryptlen ---------> + * <- authsize -> + * <---------------- total_in ------------------> + * + * OUTPUT = AssocData || PlainText + * <- assoclen -> <- crypten - authsize -> + * <---------- total_out -----------------> + */ + cryp->areq = areq; + cryp->authsize = crypto_aead_authsize(crypto_aead_reqtfm(areq)); + cryp->total_in = areq->assoclen + areq->cryptlen; + if (is_encrypt(cryp)) + /* Append auth tag to output */ + cryp->total_out = cryp->total_in + cryp->authsize; + else + /* No auth tag in output */ + cryp->total_out = cryp->total_in - cryp->authsize; + } cryp->total_in_save = cryp->total_in; cryp->total_out_save = cryp->total_out; - cryp->in_sg = req->src; - cryp->out_sg = req->dst; + cryp->in_sg = req ? req->src : areq->src; + cryp->out_sg = req ? req->dst : areq->dst; cryp->out_sg_save = cryp->out_sg; cryp->in_sg_len = sg_nents_for_len(cryp->in_sg, cryp->total_in); @@ -696,6 +986,12 @@ static int stm32_cryp_prepare_req(struct crypto_engine *engine, scatterwalk_start(&cryp->in_walk, cryp->in_sg); scatterwalk_start(&cryp->out_walk, cryp->out_sg); + if (is_gcm(cryp) || is_ccm(cryp)) { + /* In output, jump after assoc data */ + scatterwalk_advance(&cryp->out_walk, cryp->areq->assoclen); + cryp->total_out -= cryp->areq->assoclen; + } + ret = stm32_cryp_hw_init(cryp); out: if (ret) @@ -711,7 +1007,7 @@ static int stm32_cryp_prepare_cipher_req(struct crypto_engine *engine, struct ablkcipher_request, base); - return stm32_cryp_prepare_req(engine, req); + return stm32_cryp_prepare_req(req, NULL); } static int stm32_cryp_cipher_one_req(struct crypto_engine *engine, void *areq) @@ -729,6 +1025,34 @@ static int stm32_cryp_cipher_one_req(struct crypto_engine *engine, void *areq) return stm32_cryp_cpu_start(cryp); } +static int stm32_cryp_prepare_aead_req(struct crypto_engine *engine, void *areq) +{ + struct aead_request *req = container_of(areq, struct aead_request, + base); + + return stm32_cryp_prepare_req(NULL, req); +} + +static int stm32_cryp_aead_one_req(struct crypto_engine *engine, void *areq) +{ + struct aead_request *req = container_of(areq, struct aead_request, + base); + struct stm32_cryp_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req)); + struct stm32_cryp *cryp = ctx->cryp; + + if (!cryp) + return -ENODEV; + + if (unlikely(!cryp->areq->assoclen && + !stm32_cryp_get_input_text_len(cryp))) { + /* No input data to process: get tag and finish */ + stm32_cryp_finish_req(cryp, 0); + return 0; + } + + return stm32_cryp_cpu_start(cryp); +} + static u32 *stm32_cryp_next_out(struct stm32_cryp *cryp, u32 *dst, unsigned int n) { @@ -761,6 +1085,111 @@ static u32 *stm32_cryp_next_in(struct stm32_cryp *cryp, u32 *src, return (u32 *)((u8 *)src + n); } +static int stm32_cryp_read_auth_tag(struct stm32_cryp *cryp) +{ + u32 cfg, size_bit, *dst, d32; + u8 *d8; + unsigned int i, j; + int ret = 0; + + /* Update Config */ + cfg = stm32_cryp_read(cryp, CRYP_CR); + + cfg &= ~CR_PH_MASK; + cfg |= CR_PH_FINAL; + cfg &= ~CR_DEC_NOT_ENC; + cfg |= CR_CRYPEN; + + stm32_cryp_write(cryp, CRYP_CR, cfg); + + if (is_gcm(cryp)) { + /* GCM: write aad and payload size (in bits) */ + size_bit = cryp->areq->assoclen * 8; + if (cryp->caps->swap_final) + size_bit = cpu_to_be32(size_bit); + + stm32_cryp_write(cryp, CRYP_DIN, 0); + stm32_cryp_write(cryp, CRYP_DIN, size_bit); + + size_bit = is_encrypt(cryp) ? cryp->areq->cryptlen : + cryp->areq->cryptlen - AES_BLOCK_SIZE; + size_bit *= 8; + if (cryp->caps->swap_final) + size_bit = cpu_to_be32(size_bit); + + stm32_cryp_write(cryp, CRYP_DIN, 0); + stm32_cryp_write(cryp, CRYP_DIN, size_bit); + } else { + /* CCM: write CTR0 */ + u8 iv[AES_BLOCK_SIZE]; + u32 *iv32 = (u32 *)iv; + + memcpy(iv, cryp->areq->iv, AES_BLOCK_SIZE); + memset(iv + AES_BLOCK_SIZE - 1 - iv[0], 0, iv[0] + 1); + + for (i = 0; i < AES_BLOCK_32; i++) { + if (!cryp->caps->padding_wa) + *iv32 = cpu_to_be32(*iv32); + stm32_cryp_write(cryp, CRYP_DIN, *iv32++); + } + } + + /* Wait for output data */ + ret = stm32_cryp_wait_output(cryp); + if (ret) { + dev_err(cryp->dev, "Timeout (read tag)\n"); + return ret; + } + + if (is_encrypt(cryp)) { + /* Get and write tag */ + dst = sg_virt(cryp->out_sg) + _walked_out; + + for (i = 0; i < AES_BLOCK_32; i++) { + if (cryp->total_out >= sizeof(u32)) { + /* Read a full u32 */ + *dst = stm32_cryp_read(cryp, CRYP_DOUT); + + dst = stm32_cryp_next_out(cryp, dst, + sizeof(u32)); + cryp->total_out -= sizeof(u32); + } else if (!cryp->total_out) { + /* Empty fifo out (data from input padding) */ + stm32_cryp_read(cryp, CRYP_DOUT); + } else { + /* Read less than an u32 */ + d32 = stm32_cryp_read(cryp, CRYP_DOUT); + d8 = (u8 *)&d32; + + for (j = 0; j < cryp->total_out; j++) { + *((u8 *)dst) = *(d8++); + dst = stm32_cryp_next_out(cryp, dst, 1); + } + cryp->total_out = 0; + } + } + } else { + /* Get and check tag */ + u32 in_tag[AES_BLOCK_32], out_tag[AES_BLOCK_32]; + + scatterwalk_map_and_copy(in_tag, cryp->in_sg, + cryp->total_in_save - cryp->authsize, + cryp->authsize, 0); + + for (i = 0; i < AES_BLOCK_32; i++) + out_tag[i] = stm32_cryp_read(cryp, CRYP_DOUT); + + if (crypto_memneq(in_tag, out_tag, cryp->authsize)) + ret = -EBADMSG; + } + + /* Disable cryp */ + cfg &= ~CR_CRYPEN; + stm32_cryp_write(cryp, CRYP_CR, cfg); + + return ret; +} + static void stm32_cryp_check_ctr_counter(struct stm32_cryp *cryp) { u32 cr; @@ -793,17 +1222,24 @@ static bool stm32_cryp_irq_read_data(struct stm32_cryp *cryp) unsigned int i, j; u32 d32, *dst; u8 *d8; + size_t tag_size; + + /* Do no read tag now (if any) */ + if (is_encrypt(cryp) && (is_gcm(cryp) || is_ccm(cryp))) + tag_size = cryp->authsize; + else + tag_size = 0; dst = sg_virt(cryp->out_sg) + _walked_out; for (i = 0; i < cryp->hw_blocksize / sizeof(u32); i++) { - if (likely(cryp->total_out >= sizeof(u32))) { + if (likely(cryp->total_out - tag_size >= sizeof(u32))) { /* Read a full u32 */ *dst = stm32_cryp_read(cryp, CRYP_DOUT); dst = stm32_cryp_next_out(cryp, dst, sizeof(u32)); cryp->total_out -= sizeof(u32); - } else if (!cryp->total_out) { + } else if (cryp->total_out == tag_size) { /* Empty fifo out (data from input padding) */ d32 = stm32_cryp_read(cryp, CRYP_DOUT); } else { @@ -811,15 +1247,15 @@ static bool stm32_cryp_irq_read_data(struct stm32_cryp *cryp) d32 = stm32_cryp_read(cryp, CRYP_DOUT); d8 = (u8 *)&d32; - for (j = 0; j < cryp->total_out; j++) { + for (j = 0; j < cryp->total_out - tag_size; j++) { *((u8 *)dst) = *(d8++); dst = stm32_cryp_next_out(cryp, dst, 1); } - cryp->total_out = 0; + cryp->total_out = tag_size; } } - return !cryp->total_out || !cryp->total_in; + return !(cryp->total_out - tag_size) || !cryp->total_in; } static void stm32_cryp_irq_write_block(struct stm32_cryp *cryp) @@ -827,33 +1263,219 @@ static void stm32_cryp_irq_write_block(struct stm32_cryp *cryp) unsigned int i, j; u32 *src; u8 d8[4]; + size_t tag_size; + + /* Do no write tag (if any) */ + if (is_decrypt(cryp) && (is_gcm(cryp) || is_ccm(cryp))) + tag_size = cryp->authsize; + else + tag_size = 0; src = sg_virt(cryp->in_sg) + _walked_in; for (i = 0; i < cryp->hw_blocksize / sizeof(u32); i++) { - if (likely(cryp->total_in >= sizeof(u32))) { + if (likely(cryp->total_in - tag_size >= sizeof(u32))) { /* Write a full u32 */ stm32_cryp_write(cryp, CRYP_DIN, *src); src = stm32_cryp_next_in(cryp, src, sizeof(u32)); cryp->total_in -= sizeof(u32); - } else if (!cryp->total_in) { + } else if (cryp->total_in == tag_size) { /* Write padding data */ stm32_cryp_write(cryp, CRYP_DIN, 0); } else { /* Write less than an u32 */ memset(d8, 0, sizeof(u32)); - for (j = 0; j < cryp->total_in; j++) { + for (j = 0; j < cryp->total_in - tag_size; j++) { d8[j] = *((u8 *)src); src = stm32_cryp_next_in(cryp, src, 1); } stm32_cryp_write(cryp, CRYP_DIN, *(u32 *)d8); - cryp->total_in = 0; + cryp->total_in = tag_size; } } } +static void stm32_cryp_irq_write_gcm_padded_data(struct stm32_cryp *cryp) +{ + int err; + u32 cfg, tmp[AES_BLOCK_32]; + size_t total_in_ori = cryp->total_in; + struct scatterlist *out_sg_ori = cryp->out_sg; + unsigned int i; + + /* 'Special workaround' procedure described in the datasheet */ + + /* a) disable ip */ + stm32_cryp_write(cryp, CRYP_IMSCR, 0); + cfg = stm32_cryp_read(cryp, CRYP_CR); + cfg &= ~CR_CRYPEN; + stm32_cryp_write(cryp, CRYP_CR, cfg); + + /* b) Update IV1R */ + stm32_cryp_write(cryp, CRYP_IV1RR, cryp->gcm_ctr - 2); + + /* c) change mode to CTR */ + cfg &= ~CR_ALGO_MASK; + cfg |= CR_AES_CTR; + stm32_cryp_write(cryp, CRYP_CR, cfg); + + /* a) enable IP */ + cfg |= CR_CRYPEN; + stm32_cryp_write(cryp, CRYP_CR, cfg); + + /* b) pad and write the last block */ + stm32_cryp_irq_write_block(cryp); + cryp->total_in = total_in_ori; + err = stm32_cryp_wait_output(cryp); + if (err) { + dev_err(cryp->dev, "Timeout (write gcm header)\n"); + return stm32_cryp_finish_req(cryp, err); + } + + /* c) get and store encrypted data */ + stm32_cryp_irq_read_data(cryp); + scatterwalk_map_and_copy(tmp, out_sg_ori, + cryp->total_in_save - total_in_ori, + total_in_ori, 0); + + /* d) change mode back to AES GCM */ + cfg &= ~CR_ALGO_MASK; + cfg |= CR_AES_GCM; + stm32_cryp_write(cryp, CRYP_CR, cfg); + + /* e) change phase to Final */ + cfg &= ~CR_PH_MASK; + cfg |= CR_PH_FINAL; + stm32_cryp_write(cryp, CRYP_CR, cfg); + + /* f) write padded data */ + for (i = 0; i < AES_BLOCK_32; i++) { + if (cryp->total_in) + stm32_cryp_write(cryp, CRYP_DIN, tmp[i]); + else + stm32_cryp_write(cryp, CRYP_DIN, 0); + + cryp->total_in -= min_t(size_t, sizeof(u32), cryp->total_in); + } + + /* g) Empty fifo out */ + err = stm32_cryp_wait_output(cryp); + if (err) { + dev_err(cryp->dev, "Timeout (write gcm header)\n"); + return stm32_cryp_finish_req(cryp, err); + } + + for (i = 0; i < AES_BLOCK_32; i++) + stm32_cryp_read(cryp, CRYP_DOUT); + + /* h) run the he normal Final phase */ + stm32_cryp_finish_req(cryp, 0); +} + +static void stm32_cryp_irq_set_npblb(struct stm32_cryp *cryp) +{ + u32 cfg, payload_bytes; + + /* disable ip, set NPBLB and reneable ip */ + cfg = stm32_cryp_read(cryp, CRYP_CR); + cfg &= ~CR_CRYPEN; + stm32_cryp_write(cryp, CRYP_CR, cfg); + + payload_bytes = is_decrypt(cryp) ? cryp->total_in - cryp->authsize : + cryp->total_in; + cfg |= (cryp->hw_blocksize - payload_bytes) << CR_NBPBL_SHIFT; + cfg |= CR_CRYPEN; + stm32_cryp_write(cryp, CRYP_CR, cfg); +} + +static void stm32_cryp_irq_write_ccm_padded_data(struct stm32_cryp *cryp) +{ + int err = 0; + u32 cfg, iv1tmp; + u32 cstmp1[AES_BLOCK_32], cstmp2[AES_BLOCK_32], tmp[AES_BLOCK_32]; + size_t last_total_out, total_in_ori = cryp->total_in; + struct scatterlist *out_sg_ori = cryp->out_sg; + unsigned int i; + + /* 'Special workaround' procedure described in the datasheet */ + cryp->flags |= FLG_CCM_PADDED_WA; + + /* a) disable ip */ + stm32_cryp_write(cryp, CRYP_IMSCR, 0); + + cfg = stm32_cryp_read(cryp, CRYP_CR); + cfg &= ~CR_CRYPEN; + stm32_cryp_write(cryp, CRYP_CR, cfg); + + /* b) get IV1 from CRYP_CSGCMCCM7 */ + iv1tmp = stm32_cryp_read(cryp, CRYP_CSGCMCCM0R + 7 * 4); + + /* c) Load CRYP_CSGCMCCMxR */ + for (i = 0; i < ARRAY_SIZE(cstmp1); i++) + cstmp1[i] = stm32_cryp_read(cryp, CRYP_CSGCMCCM0R + i * 4); + + /* d) Write IV1R */ + stm32_cryp_write(cryp, CRYP_IV1RR, iv1tmp); + + /* e) change mode to CTR */ + cfg &= ~CR_ALGO_MASK; + cfg |= CR_AES_CTR; + stm32_cryp_write(cryp, CRYP_CR, cfg); + + /* a) enable IP */ + cfg |= CR_CRYPEN; + stm32_cryp_write(cryp, CRYP_CR, cfg); + + /* b) pad and write the last block */ + stm32_cryp_irq_write_block(cryp); + cryp->total_in = total_in_ori; + err = stm32_cryp_wait_output(cryp); + if (err) { + dev_err(cryp->dev, "Timeout (wite ccm padded data)\n"); + return stm32_cryp_finish_req(cryp, err); + } + + /* c) get and store decrypted data */ + last_total_out = cryp->total_out; + stm32_cryp_irq_read_data(cryp); + + memset(tmp, 0, sizeof(tmp)); + scatterwalk_map_and_copy(tmp, out_sg_ori, + cryp->total_out_save - last_total_out, + last_total_out, 0); + + /* d) Load again CRYP_CSGCMCCMxR */ + for (i = 0; i < ARRAY_SIZE(cstmp2); i++) + cstmp2[i] = stm32_cryp_read(cryp, CRYP_CSGCMCCM0R + i * 4); + + /* e) change mode back to AES CCM */ + cfg &= ~CR_ALGO_MASK; + cfg |= CR_AES_CCM; + stm32_cryp_write(cryp, CRYP_CR, cfg); + + /* f) change phase to header */ + cfg &= ~CR_PH_MASK; + cfg |= CR_PH_HEADER; + stm32_cryp_write(cryp, CRYP_CR, cfg); + + /* g) XOR and write padded data */ + for (i = 0; i < ARRAY_SIZE(tmp); i++) { + tmp[i] ^= cstmp1[i]; + tmp[i] ^= cstmp2[i]; + stm32_cryp_write(cryp, CRYP_DIN, tmp[i]); + } + + /* h) wait for completion */ + err = stm32_cryp_wait_busy(cryp); + if (err) + dev_err(cryp->dev, "Timeout (wite ccm padded data)\n"); + + /* i) run the he normal Final phase */ + stm32_cryp_finish_req(cryp, err); +} + static void stm32_cryp_irq_write_data(struct stm32_cryp *cryp) { if (unlikely(!cryp->total_in)) { @@ -861,28 +1483,220 @@ static void stm32_cryp_irq_write_data(struct stm32_cryp *cryp) return; } + if (unlikely(cryp->total_in < AES_BLOCK_SIZE && + (stm32_cryp_get_hw_mode(cryp) == CR_AES_GCM) && + is_encrypt(cryp))) { + /* Padding for AES GCM encryption */ + if (cryp->caps->padding_wa) + /* Special case 1 */ + return stm32_cryp_irq_write_gcm_padded_data(cryp); + + /* Setting padding bytes (NBBLB) */ + stm32_cryp_irq_set_npblb(cryp); + } + + if (unlikely((cryp->total_in - cryp->authsize < AES_BLOCK_SIZE) && + (stm32_cryp_get_hw_mode(cryp) == CR_AES_CCM) && + is_decrypt(cryp))) { + /* Padding for AES CCM decryption */ + if (cryp->caps->padding_wa) + /* Special case 2 */ + return stm32_cryp_irq_write_ccm_padded_data(cryp); + + /* Setting padding bytes (NBBLB) */ + stm32_cryp_irq_set_npblb(cryp); + } + if (is_aes(cryp) && is_ctr(cryp)) stm32_cryp_check_ctr_counter(cryp); stm32_cryp_irq_write_block(cryp); } +static void stm32_cryp_irq_write_gcm_header(struct stm32_cryp *cryp) +{ + int err; + unsigned int i, j; + u32 cfg, *src; + + src = sg_virt(cryp->in_sg) + _walked_in; + + for (i = 0; i < AES_BLOCK_32; i++) { + stm32_cryp_write(cryp, CRYP_DIN, *src); + + src = stm32_cryp_next_in(cryp, src, sizeof(u32)); + cryp->total_in -= min_t(size_t, sizeof(u32), cryp->total_in); + + /* Check if whole header written */ + if ((cryp->total_in_save - cryp->total_in) == + cryp->areq->assoclen) { + /* Write padding if needed */ + for (j = i + 1; j < AES_BLOCK_32; j++) + stm32_cryp_write(cryp, CRYP_DIN, 0); + + /* Wait for completion */ + err = stm32_cryp_wait_busy(cryp); + if (err) { + dev_err(cryp->dev, "Timeout (gcm header)\n"); + return stm32_cryp_finish_req(cryp, err); + } + + if (stm32_cryp_get_input_text_len(cryp)) { + /* Phase 3 : payload */ + cfg = stm32_cryp_read(cryp, CRYP_CR); + cfg &= ~CR_CRYPEN; + stm32_cryp_write(cryp, CRYP_CR, cfg); + + cfg &= ~CR_PH_MASK; + cfg |= CR_PH_PAYLOAD; + cfg |= CR_CRYPEN; + stm32_cryp_write(cryp, CRYP_CR, cfg); + } else { + /* Phase 4 : tag */ + stm32_cryp_write(cryp, CRYP_IMSCR, 0); + stm32_cryp_finish_req(cryp, 0); + } + + break; + } + + if (!cryp->total_in) + break; + } +} + +static void stm32_cryp_irq_write_ccm_header(struct stm32_cryp *cryp) +{ + int err; + unsigned int i = 0, j, k; + u32 alen, cfg, *src; + u8 d8[4]; + + src = sg_virt(cryp->in_sg) + _walked_in; + alen = cryp->areq->assoclen; + + if (!_walked_in) { + if (cryp->areq->assoclen <= 65280) { + /* Write first u32 of B1 */ + d8[0] = (alen >> 8) & 0xFF; + d8[1] = alen & 0xFF; + d8[2] = *((u8 *)src); + src = stm32_cryp_next_in(cryp, src, 1); + d8[3] = *((u8 *)src); + src = stm32_cryp_next_in(cryp, src, 1); + + stm32_cryp_write(cryp, CRYP_DIN, *(u32 *)d8); + i++; + + cryp->total_in -= min_t(size_t, 2, cryp->total_in); + } else { + /* Build the two first u32 of B1 */ + d8[0] = 0xFF; + d8[1] = 0xFE; + d8[2] = alen & 0xFF000000; + d8[3] = alen & 0x00FF0000; + + stm32_cryp_write(cryp, CRYP_DIN, *(u32 *)d8); + i++; + + d8[0] = alen & 0x0000FF00; + d8[1] = alen & 0x000000FF; + d8[2] = *((u8 *)src); + src = stm32_cryp_next_in(cryp, src, 1); + d8[3] = *((u8 *)src); + src = stm32_cryp_next_in(cryp, src, 1); + + stm32_cryp_write(cryp, CRYP_DIN, *(u32 *)d8); + i++; + + cryp->total_in -= min_t(size_t, 2, cryp->total_in); + } + } + + /* Write next u32 */ + for (; i < AES_BLOCK_32; i++) { + /* Build an u32 */ + memset(d8, 0, sizeof(u32)); + for (k = 0; k < sizeof(u32); k++) { + d8[k] = *((u8 *)src); + src = stm32_cryp_next_in(cryp, src, 1); + + cryp->total_in -= min_t(size_t, 1, cryp->total_in); + if ((cryp->total_in_save - cryp->total_in) == alen) + break; + } + + stm32_cryp_write(cryp, CRYP_DIN, *(u32 *)d8); + + if ((cryp->total_in_save - cryp->total_in) == alen) { + /* Write padding if needed */ + for (j = i + 1; j < AES_BLOCK_32; j++) + stm32_cryp_write(cryp, CRYP_DIN, 0); + + /* Wait for completion */ + err = stm32_cryp_wait_busy(cryp); + if (err) { + dev_err(cryp->dev, "Timeout (ccm header)\n"); + return stm32_cryp_finish_req(cryp, err); + } + + if (stm32_cryp_get_input_text_len(cryp)) { + /* Phase 3 : payload */ + cfg = stm32_cryp_read(cryp, CRYP_CR); + cfg &= ~CR_CRYPEN; + stm32_cryp_write(cryp, CRYP_CR, cfg); + + cfg &= ~CR_PH_MASK; + cfg |= CR_PH_PAYLOAD; + cfg |= CR_CRYPEN; + stm32_cryp_write(cryp, CRYP_CR, cfg); + } else { + /* Phase 4 : tag */ + stm32_cryp_write(cryp, CRYP_IMSCR, 0); + stm32_cryp_finish_req(cryp, 0); + } + + break; + } + } +} + static irqreturn_t stm32_cryp_irq_thread(int irq, void *arg) { struct stm32_cryp *cryp = arg; + u32 ph; if (cryp->irq_status & MISR_OUT) /* Output FIFO IRQ: read data */ if (unlikely(stm32_cryp_irq_read_data(cryp))) { /* All bytes processed, finish */ stm32_cryp_write(cryp, CRYP_IMSCR, 0); - stm32_cryp_finish_req(cryp); + stm32_cryp_finish_req(cryp, 0); return IRQ_HANDLED; } if (cryp->irq_status & MISR_IN) { - /* Input FIFO IRQ: write data */ - stm32_cryp_irq_write_data(cryp); + if (is_gcm(cryp)) { + ph = stm32_cryp_read(cryp, CRYP_CR) & CR_PH_MASK; + if (unlikely(ph == CR_PH_HEADER)) + /* Write Header */ + stm32_cryp_irq_write_gcm_header(cryp); + else + /* Input FIFO IRQ: write data */ + stm32_cryp_irq_write_data(cryp); + cryp->gcm_ctr++; + } else if (is_ccm(cryp)) { + ph = stm32_cryp_read(cryp, CRYP_CR) & CR_PH_MASK; + if (unlikely(ph == CR_PH_HEADER)) + /* Write Header */ + stm32_cryp_irq_write_ccm_header(cryp); + else + /* Input FIFO IRQ: write data */ + stm32_cryp_irq_write_data(cryp); + } else { + /* Input FIFO IRQ: write data */ + stm32_cryp_irq_write_data(cryp); + } } return IRQ_HANDLED; @@ -1044,8 +1858,56 @@ static struct crypto_alg crypto_algs[] = { }, }; +static struct aead_alg aead_algs[] = { +{ + .setkey = stm32_cryp_aes_aead_setkey, + .setauthsize = stm32_cryp_aes_gcm_setauthsize, + .encrypt = stm32_cryp_aes_gcm_encrypt, + .decrypt = stm32_cryp_aes_gcm_decrypt, + .init = stm32_cryp_aes_aead_init, + .ivsize = 12, + .maxauthsize = AES_BLOCK_SIZE, + + .base = { + .cra_name = "gcm(aes)", + .cra_driver_name = "stm32-gcm-aes", + .cra_priority = 200, + .cra_flags = CRYPTO_ALG_ASYNC, + .cra_blocksize = 1, + .cra_ctxsize = sizeof(struct stm32_cryp_ctx), + .cra_alignmask = 0xf, + .cra_module = THIS_MODULE, + }, +}, +{ + .setkey = stm32_cryp_aes_aead_setkey, + .setauthsize = stm32_cryp_aes_ccm_setauthsize, + .encrypt = stm32_cryp_aes_ccm_encrypt, + .decrypt = stm32_cryp_aes_ccm_decrypt, + .init = stm32_cryp_aes_aead_init, + .ivsize = AES_BLOCK_SIZE, + .maxauthsize = AES_BLOCK_SIZE, + + .base = { + .cra_name = "ccm(aes)", + .cra_driver_name = "stm32-ccm-aes", + .cra_priority = 200, + .cra_flags = CRYPTO_ALG_ASYNC, + .cra_blocksize = 1, + .cra_ctxsize = sizeof(struct stm32_cryp_ctx), + .cra_alignmask = 0xf, + .cra_module = THIS_MODULE, + }, +}, +}; + +static const struct stm32_cryp_caps f7_data = { + .swap_final = true, + .padding_wa = true, +}; + static const struct of_device_id stm32_dt_ids[] = { - { .compatible = "st,stm32f756-cryp", }, + { .compatible = "st,stm32f756-cryp", .data = &f7_data}, {}, }; MODULE_DEVICE_TABLE(of, stm32_dt_ids); @@ -1062,6 +1924,10 @@ static int stm32_cryp_probe(struct platform_device *pdev) if (!cryp) return -ENOMEM; + cryp->caps = of_device_get_match_data(dev); + if (!cryp->caps) + return -ENODEV; + cryp->dev = dev; mutex_init(&cryp->lock); @@ -1130,10 +1996,16 @@ static int stm32_cryp_probe(struct platform_device *pdev) goto err_algs; } + ret = crypto_register_aeads(aead_algs, ARRAY_SIZE(aead_algs)); + if (ret) + goto err_aead_algs; + dev_info(dev, "Initialized\n"); return 0; +err_aead_algs: + crypto_unregister_algs(crypto_algs, ARRAY_SIZE(crypto_algs)); err_algs: err_engine2: crypto_engine_exit(cryp->engine); @@ -1154,6 +2026,7 @@ static int stm32_cryp_remove(struct platform_device *pdev) if (!cryp) return -ENODEV; + crypto_unregister_aeads(aead_algs, ARRAY_SIZE(aead_algs)); crypto_unregister_algs(crypto_algs, ARRAY_SIZE(crypto_algs)); crypto_engine_exit(cryp->engine); -- cgit v1.2.1