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Release 4.14 drivers/crypto/padlock-aes.c

Directory: drivers/crypto
/* 
 * 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/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/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; }

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Sebastian Andrzej Siewior1565.22%150.00%
Michal Ludvig834.78%150.00%
Total23100.00%2100.00%


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); }

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Sebastian Andrzej Siewior4075.47%150.00%
Michal Ludvig1324.53%150.00%
Total53100.00%2100.00%


static inline struct aes_ctx *aes_ctx(struct crypto_tfm *tfm) { return aes_ctx_common(crypto_tfm_ctx(tfm)); }

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Sebastian Andrzej Siewior1565.22%150.00%
Michal Ludvig834.78%150.00%
Total23100.00%2100.00%


static inline struct aes_ctx *blk_aes_ctx(struct crypto_blkcipher *tfm) { return aes_ctx_common(crypto_blkcipher_ctx(tfm)); }

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Sebastian Andrzej Siewior2295.65%150.00%
Michal Ludvig14.35%150.00%
Total23100.00%2100.00%


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; u32 *flags = &tfm->crt_flags; struct crypto_aes_ctx gen_aes; int cpu; if (key_len % 8) { *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN; 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 (crypto_aes_expand_key(&gen_aes, in_key, key_len)) { *flags |= CRYPTO_TFM_RES_BAD_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; }

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Sebastian Andrzej Siewior27473.26%125.00%
Michal Ludvig4913.10%125.00%
Herbert Xu4812.83%125.00%
Tejun Heo30.80%125.00%
Total374100.00%4100.00%

/* ====== 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 }

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Herbert Xu3173.81%250.00%
Sebastian Andrzej Siewior1023.81%125.00%
Tejun Heo12.38%125.00%
Total42100.00%4100.00%


static inline void padlock_store_cword(struct cword *cword) { per_cpu(paes_last_cword, raw_smp_processor_id()) = cword; }

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Herbert Xu2195.45%150.00%
Tejun Heo14.55%150.00%
Total22100.00%2100.00%

/* * 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)); }

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Herbert Xu2884.85%250.00%
Chuck Ebbert515.15%250.00%
Total33100.00%4100.00%


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; }

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Chuck Ebbert41100.00%1100.00%
Total41100.00%1100.00%


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); }

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Herbert Xu6881.93%250.00%
Chuck Ebbert1518.07%250.00%
Total83100.00%4100.00%


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); }

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Chuck Ebbert91100.00%1100.00%
Total91100.00%1100.00%


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); }

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Herbert Xu5475.00%125.00%
Chuck Ebbert1520.83%250.00%
Geliang Tang34.17%125.00%
Total72100.00%4100.00%


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); }

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Chuck Ebbert7796.25%150.00%
Geliang Tang33.75%150.00%
Total80100.00%2100.00%


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; } 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 - initial)); }

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PersonTokensPropCommitsCommitProp
Chuck Ebbert2635.14%240.00%
Michal Ludvig2533.78%120.00%
Herbert Xu2331.08%240.00%
Total74100.00%5100.00%


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); 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-initial)); return iv; }

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Chuck Ebbert4352.44%125.00%
Herbert Xu3947.56%375.00%
Total82100.00%4100.00%


static void 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); }

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Herbert Xu3550.00%457.14%
Michal Ludvig3245.71%114.29%
Chuck Ebbert34.29%228.57%
Total70100.00%7100.00%


static void 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); }

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PersonTokensPropCommitsCommitProp
Herbert Xu4665.71%457.14%
Michal Ludvig2130.00%114.29%
Chuck Ebbert34.29%228.57%
Total70100.00%7100.00%

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 = aes_encrypt, .cia_decrypt = aes_decrypt, } } };
static int ecb_aes_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { struct aes_ctx *ctx = blk_aes_ctx(desc->tfm); struct blkcipher_walk walk; int err; padlock_reset_key(&ctx->cword.encrypt); blkcipher_walk_init(&walk, dst, src, nbytes); err = blkcipher_walk_virt(desc, &walk); while ((nbytes = walk.nbytes)) { 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 = blkcipher_walk_done(desc, &walk, nbytes); } padlock_store_cword(&ctx->cword.encrypt); return err; }

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Herbert Xu12883.66%360.00%
Michal Ludvig2516.34%240.00%
Total153100.00%5100.00%


static int ecb_aes_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { struct aes_ctx *ctx = blk_aes_ctx(desc->tfm); struct blkcipher_walk walk; int err; padlock_reset_key(&ctx->cword.decrypt); blkcipher_walk_init(&walk, dst, src, nbytes); err = blkcipher_walk_virt(desc, &walk); while ((nbytes = walk.nbytes)) { 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 = blkcipher_walk_done(desc, &walk, nbytes); } padlock_store_cword(&ctx->cword.encrypt); return err; }

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Herbert Xu14997.39%360.00%
Michal Ludvig42.61%240.00%
Total153100.00%5100.00%

static struct crypto_alg ecb_aes_alg = { .cra_name = "ecb(aes)", .cra_driver_name = "ecb-aes-padlock", .cra_priority = PADLOCK_COMPOSITE_PRIORITY, .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER, .cra_blocksize = AES_BLOCK_SIZE, .cra_ctxsize = sizeof(struct aes_ctx), .cra_alignmask = PADLOCK_ALIGNMENT - 1, .cra_type = &crypto_blkcipher_type, .cra_module = THIS_MODULE, .cra_u = { .blkcipher = { .min_keysize = AES_MIN_KEY_SIZE, .max_keysize = AES_MAX_KEY_SIZE, .setkey = aes_set_key, .encrypt = ecb_aes_encrypt, .decrypt = ecb_aes_decrypt, } } };
static int cbc_aes_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { struct aes_ctx *ctx = blk_aes_ctx(desc->tfm); struct blkcipher_walk walk; int err; padlock_reset_key(&ctx->cword.encrypt); blkcipher_walk_init(&walk, dst, src, nbytes); err = blkcipher_walk_virt(desc, &walk); while ((nbytes = walk.nbytes)) { 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 = blkcipher_walk_done(desc, &walk, nbytes); } padlock_store_cword(&ctx->cword.decrypt); return err; }

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Herbert Xu172100.00%3100.00%
Total172100.00%3100.00%


static int cbc_aes_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { struct aes_ctx *ctx = blk_aes_ctx(desc->tfm); struct blkcipher_walk walk; int err; padlock_reset_key(&ctx->cword.encrypt); blkcipher_walk_init(&walk, dst, src, nbytes); err = blkcipher_walk_virt(desc, &walk); while ((nbytes = walk.nbytes)) { 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 = blkcipher_walk_done(desc, &walk, nbytes); } padlock_store_cword(&ctx->cword.encrypt); return err; }

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Herbert Xu157100.00%3100.00%
Total157100.00%3100.00%

static struct crypto_alg cbc_aes_alg = { .cra_name = "cbc(aes)", .cra_driver_name = "cbc-aes-padlock", .cra_priority = PADLOCK_COMPOSITE_PRIORITY, .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER, .cra_blocksize = AES_BLOCK_SIZE, .cra_ctxsize = sizeof(struct aes_ctx), .cra_alignmask = PADLOCK_ALIGNMENT - 1, .cra_type = &crypto_blkcipher_type, .cra_module = THIS_MODULE, .cra_u = { .blkcipher = { .min_keysize = AES_MIN_KEY_SIZE, .max_keysize = AES_MAX_KEY_SIZE, .ivsize = AES_BLOCK_SIZE, .setkey = aes_set_key, .encrypt = cbc_aes_encrypt, .decrypt = cbc_aes_decrypt, } } }; static struct x86_cpu_id padlock_cpu_id[] = { X86_FEATURE_MATCH(X86_FEATURE_XCRYPT), {} }; 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))) goto aes_err; if ((ret = crypto_register_alg(&ecb_aes_alg))) goto ecb_aes_err; if ((ret = crypto_register_alg(&cbc_aes_alg))) 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_mask == 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_alg(&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; }

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PersonTokensPropCommitsCommitProp
Herbert Xu11867.82%116.67%
Chuck Ebbert4727.01%233.33%
Borislav Petkov42.30%116.67%
Andi Kleen42.30%116.67%
Jeremy Katz10.57%116.67%
Total174100.00%6100.00%


static void __exit padlock_fini(void) { crypto_unregister_alg(&cbc_aes_alg); crypto_unregister_alg(&ecb_aes_alg); crypto_unregister_alg(&aes_alg); }

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Herbert Xu2074.07%150.00%
Michal Ludvig725.93%150.00%
Total27100.00%2100.00%

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");

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PersonTokensPropCommitsCommitProp
Herbert Xu138552.88%1443.75%
Sebastian Andrzej Siewior40115.31%39.38%
Chuck Ebbert40015.27%26.25%
Michal Ludvig38114.55%412.50%
Andi Kleen291.11%13.12%
Tejun Heo90.34%26.25%
Geliang Tang60.23%13.12%
Borislav Petkov40.15%13.12%
Ingo Molnar10.04%13.12%
Jeremy Katz10.04%13.12%
Andrew Lutomirski10.04%13.12%
Kees Cook10.04%13.12%
Total2619100.00%32100.00%
Directory: drivers/crypto
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