On Wed, Aug 21, 2019 at 05:32:51PM +0300, Ard Biesheuvel wrote: > Instead of relying on the CTS template to wrap the accelerated CBC > skcipher, implement the ciphertext stealing part directly. > > Signed-off-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> For arm:allmodconfig built with gcc 9.2.0, this patch results in arch/arm/crypto/aes-ce-core.S: Assembler messages: arch/arm/crypto/aes-ce-core.S:299: Error: selected processor does not support `movw ip,:lower16:.Lcts_permute_table' in ARM mode arch/arm/crypto/aes-ce-core.S:300: Error: selected processor does not support `movt ip,:upper16:.Lcts_permute_table' in ARM mode arch/arm/crypto/aes-ce-core.S:337: Error: selected processor does not support `movw ip,:lower16:.Lcts_permute_table' in ARM mode arch/arm/crypto/aes-ce-core.S:338: Error: selected processor does not support `movt ip,:upper16:.Lcts_permute_table' in ARM mode arch/arm/crypto/aes-ce-core.S:552: Error: selected processor does not support `movw ip,:lower16:.Lcts_permute_table' in ARM mode arch/arm/crypto/aes-ce-core.S:553: Error: selected processor does not support `movt ip,:upper16:.Lcts_permute_table' in ARM mode arch/arm/crypto/aes-ce-core.S:638: Error: selected processor does not support `movw ip,:lower16:.Lcts_permute_table' in ARM mode arch/arm/crypto/aes-ce-core.S:639: Error: selected processor does not support `movt ip,:upper16:.Lcts_permute_table' in ARM mode Any idea how to avoid that ? Guenter > --- > arch/arm/crypto/aes-ce-core.S | 85 +++++++++ > arch/arm/crypto/aes-ce-glue.c | 188 ++++++++++++++++++-- > 2 files changed, 256 insertions(+), 17 deletions(-) > > diff --git a/arch/arm/crypto/aes-ce-core.S b/arch/arm/crypto/aes-ce-core.S > index 763e51604ab6..b978cdf133af 100644 > --- a/arch/arm/crypto/aes-ce-core.S > +++ b/arch/arm/crypto/aes-ce-core.S > @@ -284,6 +284,91 @@ ENTRY(ce_aes_cbc_decrypt) > pop {r4-r6, pc} > ENDPROC(ce_aes_cbc_decrypt) > > + > + /* > + * ce_aes_cbc_cts_encrypt(u8 out[], u8 const in[], u32 const rk[], > + * int rounds, int bytes, u8 const iv[]) > + * ce_aes_cbc_cts_decrypt(u8 out[], u8 const in[], u32 const rk[], > + * int rounds, int bytes, u8 const iv[]) > + */ > + > +ENTRY(ce_aes_cbc_cts_encrypt) > + push {r4-r6, lr} > + ldrd r4, r5, [sp, #16] > + > + movw ip, :lower16:.Lcts_permute_table > + movt ip, :upper16:.Lcts_permute_table > + sub r4, r4, #16 > + add lr, ip, #32 > + add ip, ip, r4 > + sub lr, lr, r4 > + vld1.8 {q5}, [ip] > + vld1.8 {q6}, [lr] > + > + add ip, r1, r4 > + vld1.8 {q0}, [r1] @ overlapping loads > + vld1.8 {q3}, [ip] > + > + vld1.8 {q1}, [r5] @ get iv > + prepare_key r2, r3 > + > + veor q0, q0, q1 @ xor with iv > + bl aes_encrypt > + > + vtbl.8 d4, {d0-d1}, d10 > + vtbl.8 d5, {d0-d1}, d11 > + vtbl.8 d2, {d6-d7}, d12 > + vtbl.8 d3, {d6-d7}, d13 > + > + veor q0, q0, q1 > + bl aes_encrypt > + > + add r4, r0, r4 > + vst1.8 {q2}, [r4] @ overlapping stores > + vst1.8 {q0}, [r0] > + > + pop {r4-r6, pc} > +ENDPROC(ce_aes_cbc_cts_encrypt) > + > +ENTRY(ce_aes_cbc_cts_decrypt) > + push {r4-r6, lr} > + ldrd r4, r5, [sp, #16] > + > + movw ip, :lower16:.Lcts_permute_table > + movt ip, :upper16:.Lcts_permute_table > + sub r4, r4, #16 > + add lr, ip, #32 > + add ip, ip, r4 > + sub lr, lr, r4 > + vld1.8 {q5}, [ip] > + vld1.8 {q6}, [lr] > + > + add ip, r1, r4 > + vld1.8 {q0}, [r1] @ overlapping loads > + vld1.8 {q1}, [ip] > + > + vld1.8 {q3}, [r5] @ get iv > + prepare_key r2, r3 > + > + bl aes_decrypt > + > + vtbl.8 d4, {d0-d1}, d10 > + vtbl.8 d5, {d0-d1}, d11 > + vtbx.8 d0, {d2-d3}, d12 > + vtbx.8 d1, {d2-d3}, d13 > + > + veor q1, q1, q2 > + bl aes_decrypt > + veor q0, q0, q3 @ xor with iv > + > + add r4, r0, r4 > + vst1.8 {q1}, [r4] @ overlapping stores > + vst1.8 {q0}, [r0] > + > + pop {r4-r6, pc} > +ENDPROC(ce_aes_cbc_cts_decrypt) > + > + > /* > * aes_ctr_encrypt(u8 out[], u8 const in[], u32 const rk[], int rounds, > * int blocks, u8 ctr[]) > diff --git a/arch/arm/crypto/aes-ce-glue.c b/arch/arm/crypto/aes-ce-glue.c > index c215792a2494..cdb1a07e7ad0 100644 > --- a/arch/arm/crypto/aes-ce-glue.c > +++ b/arch/arm/crypto/aes-ce-glue.c > @@ -35,6 +35,10 @@ asmlinkage void ce_aes_cbc_encrypt(u8 out[], u8 const in[], u32 const rk[], > int rounds, int blocks, u8 iv[]); > asmlinkage void ce_aes_cbc_decrypt(u8 out[], u8 const in[], u32 const rk[], > int rounds, int blocks, u8 iv[]); > +asmlinkage void ce_aes_cbc_cts_encrypt(u8 out[], u8 const in[], u32 const rk[], > + int rounds, int bytes, u8 const iv[]); > +asmlinkage void ce_aes_cbc_cts_decrypt(u8 out[], u8 const in[], u32 const rk[], > + int rounds, int bytes, u8 const iv[]); > > asmlinkage void ce_aes_ctr_encrypt(u8 out[], u8 const in[], u32 const rk[], > int rounds, int blocks, u8 ctr[]); > @@ -210,48 +214,182 @@ static int ecb_decrypt(struct skcipher_request *req) > return err; > } > > -static int cbc_encrypt(struct skcipher_request *req) > +static int cbc_encrypt_walk(struct skcipher_request *req, > + struct skcipher_walk *walk) > { > struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); > struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm); > - struct skcipher_walk walk; > unsigned int blocks; > - int err; > + int err = 0; > > - err = skcipher_walk_virt(&walk, req, false); > - > - while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) { > + while ((blocks = (walk->nbytes / AES_BLOCK_SIZE))) { > kernel_neon_begin(); > - ce_aes_cbc_encrypt(walk.dst.virt.addr, walk.src.virt.addr, > + ce_aes_cbc_encrypt(walk->dst.virt.addr, walk->src.virt.addr, > ctx->key_enc, num_rounds(ctx), blocks, > - walk.iv); > + walk->iv); > kernel_neon_end(); > - err = skcipher_walk_done(&walk, walk.nbytes % AES_BLOCK_SIZE); > + err = skcipher_walk_done(walk, walk->nbytes % AES_BLOCK_SIZE); > } > return err; > } > > -static int cbc_decrypt(struct skcipher_request *req) > +static int cbc_encrypt(struct skcipher_request *req) > { > - struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); > - struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm); > struct skcipher_walk walk; > - unsigned int blocks; > int err; > > err = skcipher_walk_virt(&walk, req, false); > + if (err) > + return err; > + return cbc_encrypt_walk(req, &walk); > +} > > - while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) { > +static int cbc_decrypt_walk(struct skcipher_request *req, > + struct skcipher_walk *walk) > +{ > + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); > + struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm); > + unsigned int blocks; > + int err = 0; > + > + while ((blocks = (walk->nbytes / AES_BLOCK_SIZE))) { > kernel_neon_begin(); > - ce_aes_cbc_decrypt(walk.dst.virt.addr, walk.src.virt.addr, > + ce_aes_cbc_decrypt(walk->dst.virt.addr, walk->src.virt.addr, > ctx->key_dec, num_rounds(ctx), blocks, > - walk.iv); > + walk->iv); > kernel_neon_end(); > - err = skcipher_walk_done(&walk, walk.nbytes % AES_BLOCK_SIZE); > + err = skcipher_walk_done(walk, walk->nbytes % AES_BLOCK_SIZE); > } > return err; > } > > +static int cbc_decrypt(struct skcipher_request *req) > +{ > + struct skcipher_walk walk; > + int err; > + > + err = skcipher_walk_virt(&walk, req, false); > + if (err) > + return err; > + return cbc_decrypt_walk(req, &walk); > +} > + > +static int cts_cbc_encrypt(struct skcipher_request *req) > +{ > + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); > + struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm); > + int cbc_blocks = DIV_ROUND_UP(req->cryptlen, AES_BLOCK_SIZE) - 2; > + struct scatterlist *src = req->src, *dst = req->dst; > + struct scatterlist sg_src[2], sg_dst[2]; > + struct skcipher_request subreq; > + struct skcipher_walk walk; > + int err; > + > + skcipher_request_set_tfm(&subreq, tfm); > + skcipher_request_set_callback(&subreq, skcipher_request_flags(req), > + NULL, NULL); > + > + if (req->cryptlen <= AES_BLOCK_SIZE) { > + if (req->cryptlen < AES_BLOCK_SIZE) > + return -EINVAL; > + cbc_blocks = 1; > + } > + > + if (cbc_blocks > 0) { > + skcipher_request_set_crypt(&subreq, req->src, req->dst, > + cbc_blocks * AES_BLOCK_SIZE, > + req->iv); > + > + err = skcipher_walk_virt(&walk, &subreq, false) ?: > + cbc_encrypt_walk(&subreq, &walk); > + if (err) > + return err; > + > + if (req->cryptlen == AES_BLOCK_SIZE) > + return 0; > + > + dst = src = scatterwalk_ffwd(sg_src, req->src, subreq.cryptlen); > + if (req->dst != req->src) > + dst = scatterwalk_ffwd(sg_dst, req->dst, > + subreq.cryptlen); > + } > + > + /* handle ciphertext stealing */ > + skcipher_request_set_crypt(&subreq, src, dst, > + req->cryptlen - cbc_blocks * AES_BLOCK_SIZE, > + req->iv); > + > + err = skcipher_walk_virt(&walk, &subreq, false); > + if (err) > + return err; > + > + kernel_neon_begin(); > + ce_aes_cbc_cts_encrypt(walk.dst.virt.addr, walk.src.virt.addr, > + ctx->key_enc, num_rounds(ctx), walk.nbytes, > + walk.iv); > + kernel_neon_end(); > + > + return skcipher_walk_done(&walk, 0); > +} > + > +static int cts_cbc_decrypt(struct skcipher_request *req) > +{ > + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); > + struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm); > + int cbc_blocks = DIV_ROUND_UP(req->cryptlen, AES_BLOCK_SIZE) - 2; > + struct scatterlist *src = req->src, *dst = req->dst; > + struct scatterlist sg_src[2], sg_dst[2]; > + struct skcipher_request subreq; > + struct skcipher_walk walk; > + int err; > + > + skcipher_request_set_tfm(&subreq, tfm); > + skcipher_request_set_callback(&subreq, skcipher_request_flags(req), > + NULL, NULL); > + > + if (req->cryptlen <= AES_BLOCK_SIZE) { > + if (req->cryptlen < AES_BLOCK_SIZE) > + return -EINVAL; > + cbc_blocks = 1; > + } > + > + if (cbc_blocks > 0) { > + skcipher_request_set_crypt(&subreq, req->src, req->dst, > + cbc_blocks * AES_BLOCK_SIZE, > + req->iv); > + > + err = skcipher_walk_virt(&walk, &subreq, false) ?: > + cbc_decrypt_walk(&subreq, &walk); > + if (err) > + return err; > + > + if (req->cryptlen == AES_BLOCK_SIZE) > + return 0; > + > + dst = src = scatterwalk_ffwd(sg_src, req->src, subreq.cryptlen); > + if (req->dst != req->src) > + dst = scatterwalk_ffwd(sg_dst, req->dst, > + subreq.cryptlen); > + } > + > + /* handle ciphertext stealing */ > + skcipher_request_set_crypt(&subreq, src, dst, > + req->cryptlen - cbc_blocks * AES_BLOCK_SIZE, > + req->iv); > + > + err = skcipher_walk_virt(&walk, &subreq, false); > + if (err) > + return err; > + > + kernel_neon_begin(); > + ce_aes_cbc_cts_decrypt(walk.dst.virt.addr, walk.src.virt.addr, > + ctx->key_dec, num_rounds(ctx), walk.nbytes, > + walk.iv); > + kernel_neon_end(); > + > + return skcipher_walk_done(&walk, 0); > +} > + > static int ctr_encrypt(struct skcipher_request *req) > { > struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); > @@ -486,6 +624,22 @@ static struct skcipher_alg aes_algs[] = { { > .setkey = ce_aes_setkey, > .encrypt = cbc_encrypt, > .decrypt = cbc_decrypt, > +}, { > + .base.cra_name = "__cts(cbc(aes))", > + .base.cra_driver_name = "__cts-cbc-aes-ce", > + .base.cra_priority = 300, > + .base.cra_flags = CRYPTO_ALG_INTERNAL, > + .base.cra_blocksize = AES_BLOCK_SIZE, > + .base.cra_ctxsize = sizeof(struct crypto_aes_ctx), > + .base.cra_module = THIS_MODULE, > + > + .min_keysize = AES_MIN_KEY_SIZE, > + .max_keysize = AES_MAX_KEY_SIZE, > + .ivsize = AES_BLOCK_SIZE, > + .walksize = 2 * AES_BLOCK_SIZE, > + .setkey = ce_aes_setkey, > + .encrypt = cts_cbc_encrypt, > + .decrypt = cts_cbc_decrypt, > }, { > .base.cra_name = "__ctr(aes)", > .base.cra_driver_name = "__ctr-aes-ce",