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crypto: lrw - prefix function and struct names with "lrw"
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Overly-generic names can cause problems like naming collisions,
confusing crash reports, and reduced grep-ability.  E.g. see
commit d099ea6 ("crypto - Avoid free() namespace collision").

Clean this up for the lrw template by prefixing the names with "lrw_".

(I didn't use "crypto_lrw_" instead because that seems overkill.)

Also constify the tfm context in a couple places.

Signed-off-by: Eric Biggers <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>
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@ebiggers @herbertx
ebiggers authored and herbertx committed Jul 16, 2020
1 parent a874f59 commit e456ef6
Showing 1 changed file with 61 additions and 58 deletions.
119 changes: 61 additions & 58 deletions crypto/lrw.c
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Original file line number Diff line number Diff line change
Expand Up @@ -27,7 +27,7 @@

#define LRW_BLOCK_SIZE 16

struct priv {
struct lrw_tfm_ctx {
struct crypto_skcipher *child;

/*
Expand All @@ -49,12 +49,12 @@ struct priv {
be128 mulinc[128];
};

struct rctx {
struct lrw_request_ctx {
be128 t;
struct skcipher_request subreq;
};

static inline void setbit128_bbe(void *b, int bit)
static inline void lrw_setbit128_bbe(void *b, int bit)
{
__set_bit(bit ^ (0x80 -
#ifdef __BIG_ENDIAN
Expand All @@ -65,10 +65,10 @@ static inline void setbit128_bbe(void *b, int bit)
), b);
}

static int setkey(struct crypto_skcipher *parent, const u8 *key,
unsigned int keylen)
static int lrw_setkey(struct crypto_skcipher *parent, const u8 *key,
unsigned int keylen)
{
struct priv *ctx = crypto_skcipher_ctx(parent);
struct lrw_tfm_ctx *ctx = crypto_skcipher_ctx(parent);
struct crypto_skcipher *child = ctx->child;
int err, bsize = LRW_BLOCK_SIZE;
const u8 *tweak = key + keylen - bsize;
Expand All @@ -92,7 +92,7 @@ static int setkey(struct crypto_skcipher *parent, const u8 *key,

/* initialize optimization table */
for (i = 0; i < 128; i++) {
setbit128_bbe(&tmp, i);
lrw_setbit128_bbe(&tmp, i);
ctx->mulinc[i] = tmp;
gf128mul_64k_bbe(&ctx->mulinc[i], ctx->table);
}
Expand All @@ -108,10 +108,10 @@ static int setkey(struct crypto_skcipher *parent, const u8 *key,
* For example:
*
* u32 counter[4] = { 0xFFFFFFFF, 0x1, 0x0, 0x0 };
* int i = next_index(&counter);
* int i = lrw_next_index(&counter);
* // i == 33, counter == { 0x0, 0x2, 0x0, 0x0 }
*/
static int next_index(u32 *counter)
static int lrw_next_index(u32 *counter)
{
int i, res = 0;

Expand All @@ -135,14 +135,14 @@ static int next_index(u32 *counter)
* We compute the tweak masks twice (both before and after the ECB encryption or
* decryption) to avoid having to allocate a temporary buffer and/or make
* mutliple calls to the 'ecb(..)' instance, which usually would be slower than
* just doing the next_index() calls again.
* just doing the lrw_next_index() calls again.
*/
static int xor_tweak(struct skcipher_request *req, bool second_pass)
static int lrw_xor_tweak(struct skcipher_request *req, bool second_pass)
{
const int bs = LRW_BLOCK_SIZE;
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
struct priv *ctx = crypto_skcipher_ctx(tfm);
struct rctx *rctx = skcipher_request_ctx(req);
const struct lrw_tfm_ctx *ctx = crypto_skcipher_ctx(tfm);
struct lrw_request_ctx *rctx = skcipher_request_ctx(req);
be128 t = rctx->t;
struct skcipher_walk w;
__be32 *iv;
Expand Down Expand Up @@ -178,7 +178,8 @@ static int xor_tweak(struct skcipher_request *req, bool second_pass)

/* T <- I*Key2, using the optimization
* discussed in the specification */
be128_xor(&t, &t, &ctx->mulinc[next_index(counter)]);
be128_xor(&t, &t,
&ctx->mulinc[lrw_next_index(counter)]);
} while ((avail -= bs) >= bs);

if (second_pass && w.nbytes == w.total) {
Expand All @@ -194,38 +195,40 @@ static int xor_tweak(struct skcipher_request *req, bool second_pass)
return err;
}

static int xor_tweak_pre(struct skcipher_request *req)
static int lrw_xor_tweak_pre(struct skcipher_request *req)
{
return xor_tweak(req, false);
return lrw_xor_tweak(req, false);
}

static int xor_tweak_post(struct skcipher_request *req)
static int lrw_xor_tweak_post(struct skcipher_request *req)
{
return xor_tweak(req, true);
return lrw_xor_tweak(req, true);
}

static void crypt_done(struct crypto_async_request *areq, int err)
static void lrw_crypt_done(struct crypto_async_request *areq, int err)
{
struct skcipher_request *req = areq->data;

if (!err) {
struct rctx *rctx = skcipher_request_ctx(req);
struct lrw_request_ctx *rctx = skcipher_request_ctx(req);

rctx->subreq.base.flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
err = xor_tweak_post(req);
err = lrw_xor_tweak_post(req);
}

skcipher_request_complete(req, err);
}

static void init_crypt(struct skcipher_request *req)
static void lrw_init_crypt(struct skcipher_request *req)
{
struct priv *ctx = crypto_skcipher_ctx(crypto_skcipher_reqtfm(req));
struct rctx *rctx = skcipher_request_ctx(req);
const struct lrw_tfm_ctx *ctx =
crypto_skcipher_ctx(crypto_skcipher_reqtfm(req));
struct lrw_request_ctx *rctx = skcipher_request_ctx(req);
struct skcipher_request *subreq = &rctx->subreq;

skcipher_request_set_tfm(subreq, ctx->child);
skcipher_request_set_callback(subreq, req->base.flags, crypt_done, req);
skcipher_request_set_callback(subreq, req->base.flags, lrw_crypt_done,
req);
/* pass req->iv as IV (will be used by xor_tweak, ECB will ignore it) */
skcipher_request_set_crypt(subreq, req->dst, req->dst,
req->cryptlen, req->iv);
Expand All @@ -237,33 +240,33 @@ static void init_crypt(struct skcipher_request *req)
gf128mul_64k_bbe(&rctx->t, ctx->table);
}

static int encrypt(struct skcipher_request *req)
static int lrw_encrypt(struct skcipher_request *req)
{
struct rctx *rctx = skcipher_request_ctx(req);
struct lrw_request_ctx *rctx = skcipher_request_ctx(req);
struct skcipher_request *subreq = &rctx->subreq;

init_crypt(req);
return xor_tweak_pre(req) ?:
lrw_init_crypt(req);
return lrw_xor_tweak_pre(req) ?:
crypto_skcipher_encrypt(subreq) ?:
xor_tweak_post(req);
lrw_xor_tweak_post(req);
}

static int decrypt(struct skcipher_request *req)
static int lrw_decrypt(struct skcipher_request *req)
{
struct rctx *rctx = skcipher_request_ctx(req);
struct lrw_request_ctx *rctx = skcipher_request_ctx(req);
struct skcipher_request *subreq = &rctx->subreq;

init_crypt(req);
return xor_tweak_pre(req) ?:
lrw_init_crypt(req);
return lrw_xor_tweak_pre(req) ?:
crypto_skcipher_decrypt(subreq) ?:
xor_tweak_post(req);
lrw_xor_tweak_post(req);
}

static int init_tfm(struct crypto_skcipher *tfm)
static int lrw_init_tfm(struct crypto_skcipher *tfm)
{
struct skcipher_instance *inst = skcipher_alg_instance(tfm);
struct crypto_skcipher_spawn *spawn = skcipher_instance_ctx(inst);
struct priv *ctx = crypto_skcipher_ctx(tfm);
struct lrw_tfm_ctx *ctx = crypto_skcipher_ctx(tfm);
struct crypto_skcipher *cipher;

cipher = crypto_spawn_skcipher(spawn);
Expand All @@ -273,27 +276,27 @@ static int init_tfm(struct crypto_skcipher *tfm)
ctx->child = cipher;

crypto_skcipher_set_reqsize(tfm, crypto_skcipher_reqsize(cipher) +
sizeof(struct rctx));
sizeof(struct lrw_request_ctx));

return 0;
}

static void exit_tfm(struct crypto_skcipher *tfm)
static void lrw_exit_tfm(struct crypto_skcipher *tfm)
{
struct priv *ctx = crypto_skcipher_ctx(tfm);
struct lrw_tfm_ctx *ctx = crypto_skcipher_ctx(tfm);

if (ctx->table)
gf128mul_free_64k(ctx->table);
crypto_free_skcipher(ctx->child);
}

static void crypto_lrw_free(struct skcipher_instance *inst)
static void lrw_free_instance(struct skcipher_instance *inst)
{
crypto_drop_skcipher(skcipher_instance_ctx(inst));
kfree(inst);
}

static int create(struct crypto_template *tmpl, struct rtattr **tb)
static int lrw_create(struct crypto_template *tmpl, struct rtattr **tb)
{
struct crypto_skcipher_spawn *spawn;
struct skcipher_instance *inst;
Expand Down Expand Up @@ -384,43 +387,43 @@ static int create(struct crypto_template *tmpl, struct rtattr **tb)
inst->alg.max_keysize = crypto_skcipher_alg_max_keysize(alg) +
LRW_BLOCK_SIZE;

inst->alg.base.cra_ctxsize = sizeof(struct priv);
inst->alg.base.cra_ctxsize = sizeof(struct lrw_tfm_ctx);

inst->alg.init = init_tfm;
inst->alg.exit = exit_tfm;
inst->alg.init = lrw_init_tfm;
inst->alg.exit = lrw_exit_tfm;

inst->alg.setkey = setkey;
inst->alg.encrypt = encrypt;
inst->alg.decrypt = decrypt;
inst->alg.setkey = lrw_setkey;
inst->alg.encrypt = lrw_encrypt;
inst->alg.decrypt = lrw_decrypt;

inst->free = crypto_lrw_free;
inst->free = lrw_free_instance;

err = skcipher_register_instance(tmpl, inst);
if (err) {
err_free_inst:
crypto_lrw_free(inst);
lrw_free_instance(inst);
}
return err;
}

static struct crypto_template crypto_tmpl = {
static struct crypto_template lrw_tmpl = {
.name = "lrw",
.create = create,
.create = lrw_create,
.module = THIS_MODULE,
};

static int __init crypto_module_init(void)
static int __init lrw_module_init(void)
{
return crypto_register_template(&crypto_tmpl);
return crypto_register_template(&lrw_tmpl);
}

static void __exit crypto_module_exit(void)
static void __exit lrw_module_exit(void)
{
crypto_unregister_template(&crypto_tmpl);
crypto_unregister_template(&lrw_tmpl);
}

subsys_initcall(crypto_module_init);
module_exit(crypto_module_exit);
subsys_initcall(lrw_module_init);
module_exit(lrw_module_exit);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("LRW block cipher mode");
Expand Down

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