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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/crypto/padlock-aes.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | drivers/crypto/padlock-aes.c | 539 |
1 files changed, 539 insertions, 0 deletions
diff --git a/drivers/crypto/padlock-aes.c b/drivers/crypto/padlock-aes.c new file mode 100644 index 000000000..1be549a07 --- /dev/null +++ b/drivers/crypto/padlock-aes.c @@ -0,0 +1,539 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Cryptographic API. + * + * Support for VIA PadLock hardware crypto engine. + * + * Copyright (c) 2004 Michal Ludvig <michal@logix.cz> + * + */ + +#include <crypto/algapi.h> +#include <crypto/aes.h> +#include <crypto/internal/skcipher.h> +#include <crypto/padlock.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/types.h> +#include <linux/errno.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/percpu.h> +#include <linux/smp.h> +#include <linux/slab.h> +#include <asm/cpu_device_id.h> +#include <asm/byteorder.h> +#include <asm/processor.h> +#include <asm/fpu/api.h> + +/* + * Number of data blocks actually fetched for each xcrypt insn. + * Processors with prefetch errata will fetch extra blocks. + */ +static unsigned int ecb_fetch_blocks = 2; +#define MAX_ECB_FETCH_BLOCKS (8) +#define ecb_fetch_bytes (ecb_fetch_blocks * AES_BLOCK_SIZE) + +static unsigned int cbc_fetch_blocks = 1; +#define MAX_CBC_FETCH_BLOCKS (4) +#define cbc_fetch_bytes (cbc_fetch_blocks * AES_BLOCK_SIZE) + +/* Control word. */ +struct cword { + unsigned int __attribute__ ((__packed__)) + rounds:4, + algo:3, + keygen:1, + interm:1, + encdec:1, + ksize:2; +} __attribute__ ((__aligned__(PADLOCK_ALIGNMENT))); + +/* Whenever making any changes to the following + * structure *make sure* you keep E, d_data + * and cword aligned on 16 Bytes boundaries and + * the Hardware can access 16 * 16 bytes of E and d_data + * (only the first 15 * 16 bytes matter but the HW reads + * more). + */ +struct aes_ctx { + u32 E[AES_MAX_KEYLENGTH_U32] + __attribute__ ((__aligned__(PADLOCK_ALIGNMENT))); + u32 d_data[AES_MAX_KEYLENGTH_U32] + __attribute__ ((__aligned__(PADLOCK_ALIGNMENT))); + struct { + struct cword encrypt; + struct cword decrypt; + } cword; + u32 *D; +}; + +static DEFINE_PER_CPU(struct cword *, paes_last_cword); + +/* Tells whether the ACE is capable to generate + the extended key for a given key_len. */ +static inline int +aes_hw_extkey_available(uint8_t key_len) +{ + /* TODO: We should check the actual CPU model/stepping + as it's possible that the capability will be + added in the next CPU revisions. */ + if (key_len == 16) + return 1; + return 0; +} + +static inline struct aes_ctx *aes_ctx_common(void *ctx) +{ + unsigned long addr = (unsigned long)ctx; + unsigned long align = PADLOCK_ALIGNMENT; + + if (align <= crypto_tfm_ctx_alignment()) + align = 1; + return (struct aes_ctx *)ALIGN(addr, align); +} + +static inline struct aes_ctx *aes_ctx(struct crypto_tfm *tfm) +{ + return aes_ctx_common(crypto_tfm_ctx(tfm)); +} + +static inline struct aes_ctx *skcipher_aes_ctx(struct crypto_skcipher *tfm) +{ + return aes_ctx_common(crypto_skcipher_ctx(tfm)); +} + +static int aes_set_key(struct crypto_tfm *tfm, const u8 *in_key, + unsigned int key_len) +{ + struct aes_ctx *ctx = aes_ctx(tfm); + const __le32 *key = (const __le32 *)in_key; + struct crypto_aes_ctx gen_aes; + int cpu; + + if (key_len % 8) + return -EINVAL; + + /* + * If the hardware is capable of generating the extended key + * itself we must supply the plain key for both encryption + * and decryption. + */ + ctx->D = ctx->E; + + ctx->E[0] = le32_to_cpu(key[0]); + ctx->E[1] = le32_to_cpu(key[1]); + ctx->E[2] = le32_to_cpu(key[2]); + ctx->E[3] = le32_to_cpu(key[3]); + + /* Prepare control words. */ + memset(&ctx->cword, 0, sizeof(ctx->cword)); + + ctx->cword.decrypt.encdec = 1; + ctx->cword.encrypt.rounds = 10 + (key_len - 16) / 4; + ctx->cword.decrypt.rounds = ctx->cword.encrypt.rounds; + ctx->cword.encrypt.ksize = (key_len - 16) / 8; + ctx->cword.decrypt.ksize = ctx->cword.encrypt.ksize; + + /* Don't generate extended keys if the hardware can do it. */ + if (aes_hw_extkey_available(key_len)) + goto ok; + + ctx->D = ctx->d_data; + ctx->cword.encrypt.keygen = 1; + ctx->cword.decrypt.keygen = 1; + + if (aes_expandkey(&gen_aes, in_key, key_len)) + return -EINVAL; + + memcpy(ctx->E, gen_aes.key_enc, AES_MAX_KEYLENGTH); + memcpy(ctx->D, gen_aes.key_dec, AES_MAX_KEYLENGTH); + +ok: + for_each_online_cpu(cpu) + if (&ctx->cword.encrypt == per_cpu(paes_last_cword, cpu) || + &ctx->cword.decrypt == per_cpu(paes_last_cword, cpu)) + per_cpu(paes_last_cword, cpu) = NULL; + + return 0; +} + +static int aes_set_key_skcipher(struct crypto_skcipher *tfm, const u8 *in_key, + unsigned int key_len) +{ + return aes_set_key(crypto_skcipher_tfm(tfm), in_key, key_len); +} + +/* ====== Encryption/decryption routines ====== */ + +/* These are the real call to PadLock. */ +static inline void padlock_reset_key(struct cword *cword) +{ + int cpu = raw_smp_processor_id(); + + if (cword != per_cpu(paes_last_cword, cpu)) +#ifndef CONFIG_X86_64 + asm volatile ("pushfl; popfl"); +#else + asm volatile ("pushfq; popfq"); +#endif +} + +static inline void padlock_store_cword(struct cword *cword) +{ + per_cpu(paes_last_cword, raw_smp_processor_id()) = cword; +} + +/* + * While the padlock instructions don't use FP/SSE registers, they + * generate a spurious DNA fault when CR0.TS is '1'. Fortunately, + * the kernel doesn't use CR0.TS. + */ + +static inline void rep_xcrypt_ecb(const u8 *input, u8 *output, void *key, + struct cword *control_word, int count) +{ + asm volatile (".byte 0xf3,0x0f,0xa7,0xc8" /* rep xcryptecb */ + : "+S"(input), "+D"(output) + : "d"(control_word), "b"(key), "c"(count)); +} + +static inline u8 *rep_xcrypt_cbc(const u8 *input, u8 *output, void *key, + u8 *iv, struct cword *control_word, int count) +{ + asm volatile (".byte 0xf3,0x0f,0xa7,0xd0" /* rep xcryptcbc */ + : "+S" (input), "+D" (output), "+a" (iv) + : "d" (control_word), "b" (key), "c" (count)); + return iv; +} + +static void ecb_crypt_copy(const u8 *in, u8 *out, u32 *key, + struct cword *cword, int count) +{ + /* + * Padlock prefetches extra data so we must provide mapped input buffers. + * Assume there are at least 16 bytes of stack already in use. + */ + u8 buf[AES_BLOCK_SIZE * (MAX_ECB_FETCH_BLOCKS - 1) + PADLOCK_ALIGNMENT - 1]; + u8 *tmp = PTR_ALIGN(&buf[0], PADLOCK_ALIGNMENT); + + memcpy(tmp, in, count * AES_BLOCK_SIZE); + rep_xcrypt_ecb(tmp, out, key, cword, count); +} + +static u8 *cbc_crypt_copy(const u8 *in, u8 *out, u32 *key, + u8 *iv, struct cword *cword, int count) +{ + /* + * Padlock prefetches extra data so we must provide mapped input buffers. + * Assume there are at least 16 bytes of stack already in use. + */ + u8 buf[AES_BLOCK_SIZE * (MAX_CBC_FETCH_BLOCKS - 1) + PADLOCK_ALIGNMENT - 1]; + u8 *tmp = PTR_ALIGN(&buf[0], PADLOCK_ALIGNMENT); + + memcpy(tmp, in, count * AES_BLOCK_SIZE); + return rep_xcrypt_cbc(tmp, out, key, iv, cword, count); +} + +static inline void ecb_crypt(const u8 *in, u8 *out, u32 *key, + struct cword *cword, int count) +{ + /* Padlock in ECB mode fetches at least ecb_fetch_bytes of data. + * We could avoid some copying here but it's probably not worth it. + */ + if (unlikely(offset_in_page(in) + ecb_fetch_bytes > PAGE_SIZE)) { + ecb_crypt_copy(in, out, key, cword, count); + return; + } + + rep_xcrypt_ecb(in, out, key, cword, count); +} + +static inline u8 *cbc_crypt(const u8 *in, u8 *out, u32 *key, + u8 *iv, struct cword *cword, int count) +{ + /* Padlock in CBC mode fetches at least cbc_fetch_bytes of data. */ + if (unlikely(offset_in_page(in) + cbc_fetch_bytes > PAGE_SIZE)) + return cbc_crypt_copy(in, out, key, iv, cword, count); + + return rep_xcrypt_cbc(in, out, key, iv, cword, count); +} + +static inline void padlock_xcrypt_ecb(const u8 *input, u8 *output, void *key, + void *control_word, u32 count) +{ + u32 initial = count & (ecb_fetch_blocks - 1); + + if (count < ecb_fetch_blocks) { + ecb_crypt(input, output, key, control_word, count); + return; + } + + count -= initial; + + if (initial) + asm volatile (".byte 0xf3,0x0f,0xa7,0xc8" /* rep xcryptecb */ + : "+S"(input), "+D"(output) + : "d"(control_word), "b"(key), "c"(initial)); + + asm volatile (".byte 0xf3,0x0f,0xa7,0xc8" /* rep xcryptecb */ + : "+S"(input), "+D"(output) + : "d"(control_word), "b"(key), "c"(count)); +} + +static inline u8 *padlock_xcrypt_cbc(const u8 *input, u8 *output, void *key, + u8 *iv, void *control_word, u32 count) +{ + u32 initial = count & (cbc_fetch_blocks - 1); + + if (count < cbc_fetch_blocks) + return cbc_crypt(input, output, key, iv, control_word, count); + + count -= initial; + + if (initial) + asm volatile (".byte 0xf3,0x0f,0xa7,0xd0" /* rep xcryptcbc */ + : "+S" (input), "+D" (output), "+a" (iv) + : "d" (control_word), "b" (key), "c" (initial)); + + asm volatile (".byte 0xf3,0x0f,0xa7,0xd0" /* rep xcryptcbc */ + : "+S" (input), "+D" (output), "+a" (iv) + : "d" (control_word), "b" (key), "c" (count)); + return iv; +} + +static void padlock_aes_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) +{ + struct aes_ctx *ctx = aes_ctx(tfm); + + padlock_reset_key(&ctx->cword.encrypt); + ecb_crypt(in, out, ctx->E, &ctx->cword.encrypt, 1); + padlock_store_cword(&ctx->cword.encrypt); +} + +static void padlock_aes_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) +{ + struct aes_ctx *ctx = aes_ctx(tfm); + + padlock_reset_key(&ctx->cword.encrypt); + ecb_crypt(in, out, ctx->D, &ctx->cword.decrypt, 1); + padlock_store_cword(&ctx->cword.encrypt); +} + +static struct crypto_alg aes_alg = { + .cra_name = "aes", + .cra_driver_name = "aes-padlock", + .cra_priority = PADLOCK_CRA_PRIORITY, + .cra_flags = CRYPTO_ALG_TYPE_CIPHER, + .cra_blocksize = AES_BLOCK_SIZE, + .cra_ctxsize = sizeof(struct aes_ctx), + .cra_alignmask = PADLOCK_ALIGNMENT - 1, + .cra_module = THIS_MODULE, + .cra_u = { + .cipher = { + .cia_min_keysize = AES_MIN_KEY_SIZE, + .cia_max_keysize = AES_MAX_KEY_SIZE, + .cia_setkey = aes_set_key, + .cia_encrypt = padlock_aes_encrypt, + .cia_decrypt = padlock_aes_decrypt, + } + } +}; + +static int ecb_aes_encrypt(struct skcipher_request *req) +{ + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); + struct aes_ctx *ctx = skcipher_aes_ctx(tfm); + struct skcipher_walk walk; + unsigned int nbytes; + int err; + + padlock_reset_key(&ctx->cword.encrypt); + + err = skcipher_walk_virt(&walk, req, false); + + while ((nbytes = walk.nbytes) != 0) { + padlock_xcrypt_ecb(walk.src.virt.addr, walk.dst.virt.addr, + ctx->E, &ctx->cword.encrypt, + nbytes / AES_BLOCK_SIZE); + nbytes &= AES_BLOCK_SIZE - 1; + err = skcipher_walk_done(&walk, nbytes); + } + + padlock_store_cword(&ctx->cword.encrypt); + + return err; +} + +static int ecb_aes_decrypt(struct skcipher_request *req) +{ + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); + struct aes_ctx *ctx = skcipher_aes_ctx(tfm); + struct skcipher_walk walk; + unsigned int nbytes; + int err; + + padlock_reset_key(&ctx->cword.decrypt); + + err = skcipher_walk_virt(&walk, req, false); + + while ((nbytes = walk.nbytes) != 0) { + padlock_xcrypt_ecb(walk.src.virt.addr, walk.dst.virt.addr, + ctx->D, &ctx->cword.decrypt, + nbytes / AES_BLOCK_SIZE); + nbytes &= AES_BLOCK_SIZE - 1; + err = skcipher_walk_done(&walk, nbytes); + } + + padlock_store_cword(&ctx->cword.encrypt); + + return err; +} + +static struct skcipher_alg ecb_aes_alg = { + .base.cra_name = "ecb(aes)", + .base.cra_driver_name = "ecb-aes-padlock", + .base.cra_priority = PADLOCK_COMPOSITE_PRIORITY, + .base.cra_blocksize = AES_BLOCK_SIZE, + .base.cra_ctxsize = sizeof(struct aes_ctx), + .base.cra_alignmask = PADLOCK_ALIGNMENT - 1, + .base.cra_module = THIS_MODULE, + .min_keysize = AES_MIN_KEY_SIZE, + .max_keysize = AES_MAX_KEY_SIZE, + .setkey = aes_set_key_skcipher, + .encrypt = ecb_aes_encrypt, + .decrypt = ecb_aes_decrypt, +}; + +static int cbc_aes_encrypt(struct skcipher_request *req) +{ + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); + struct aes_ctx *ctx = skcipher_aes_ctx(tfm); + struct skcipher_walk walk; + unsigned int nbytes; + int err; + + padlock_reset_key(&ctx->cword.encrypt); + + err = skcipher_walk_virt(&walk, req, false); + + while ((nbytes = walk.nbytes) != 0) { + u8 *iv = padlock_xcrypt_cbc(walk.src.virt.addr, + walk.dst.virt.addr, ctx->E, + walk.iv, &ctx->cword.encrypt, + nbytes / AES_BLOCK_SIZE); + memcpy(walk.iv, iv, AES_BLOCK_SIZE); + nbytes &= AES_BLOCK_SIZE - 1; + err = skcipher_walk_done(&walk, nbytes); + } + + padlock_store_cword(&ctx->cword.decrypt); + + return err; +} + +static int cbc_aes_decrypt(struct skcipher_request *req) +{ + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); + struct aes_ctx *ctx = skcipher_aes_ctx(tfm); + struct skcipher_walk walk; + unsigned int nbytes; + int err; + + padlock_reset_key(&ctx->cword.encrypt); + + err = skcipher_walk_virt(&walk, req, false); + + while ((nbytes = walk.nbytes) != 0) { + padlock_xcrypt_cbc(walk.src.virt.addr, walk.dst.virt.addr, + ctx->D, walk.iv, &ctx->cword.decrypt, + nbytes / AES_BLOCK_SIZE); + nbytes &= AES_BLOCK_SIZE - 1; + err = skcipher_walk_done(&walk, nbytes); + } + + padlock_store_cword(&ctx->cword.encrypt); + + return err; +} + +static struct skcipher_alg cbc_aes_alg = { + .base.cra_name = "cbc(aes)", + .base.cra_driver_name = "cbc-aes-padlock", + .base.cra_priority = PADLOCK_COMPOSITE_PRIORITY, + .base.cra_blocksize = AES_BLOCK_SIZE, + .base.cra_ctxsize = sizeof(struct aes_ctx), + .base.cra_alignmask = PADLOCK_ALIGNMENT - 1, + .base.cra_module = THIS_MODULE, + .min_keysize = AES_MIN_KEY_SIZE, + .max_keysize = AES_MAX_KEY_SIZE, + .ivsize = AES_BLOCK_SIZE, + .setkey = aes_set_key_skcipher, + .encrypt = cbc_aes_encrypt, + .decrypt = cbc_aes_decrypt, +}; + +static const struct x86_cpu_id padlock_cpu_id[] = { + X86_MATCH_FEATURE(X86_FEATURE_XCRYPT, NULL), + {} +}; +MODULE_DEVICE_TABLE(x86cpu, padlock_cpu_id); + +static int __init padlock_init(void) +{ + int ret; + struct cpuinfo_x86 *c = &cpu_data(0); + + if (!x86_match_cpu(padlock_cpu_id)) + return -ENODEV; + + if (!boot_cpu_has(X86_FEATURE_XCRYPT_EN)) { + printk(KERN_NOTICE PFX "VIA PadLock detected, but not enabled. Hmm, strange...\n"); + return -ENODEV; + } + + if ((ret = crypto_register_alg(&aes_alg)) != 0) + goto aes_err; + + if ((ret = crypto_register_skcipher(&ecb_aes_alg)) != 0) + goto ecb_aes_err; + + if ((ret = crypto_register_skcipher(&cbc_aes_alg)) != 0) + goto cbc_aes_err; + + printk(KERN_NOTICE PFX "Using VIA PadLock ACE for AES algorithm.\n"); + + if (c->x86 == 6 && c->x86_model == 15 && c->x86_stepping == 2) { + ecb_fetch_blocks = MAX_ECB_FETCH_BLOCKS; + cbc_fetch_blocks = MAX_CBC_FETCH_BLOCKS; + printk(KERN_NOTICE PFX "VIA Nano stepping 2 detected: enabling workaround.\n"); + } + +out: + return ret; + +cbc_aes_err: + crypto_unregister_skcipher(&ecb_aes_alg); +ecb_aes_err: + crypto_unregister_alg(&aes_alg); +aes_err: + printk(KERN_ERR PFX "VIA PadLock AES initialization failed.\n"); + goto out; +} + +static void __exit padlock_fini(void) +{ + crypto_unregister_skcipher(&cbc_aes_alg); + crypto_unregister_skcipher(&ecb_aes_alg); + crypto_unregister_alg(&aes_alg); +} + +module_init(padlock_init); +module_exit(padlock_fini); + +MODULE_DESCRIPTION("VIA PadLock AES algorithm support"); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Michal Ludvig"); + +MODULE_ALIAS_CRYPTO("aes"); |