crypto: drbg - Remove drbg_core

Now that none of the information in struct drbg_core is used, remove it.

The null-ity of the pointer drbg_state::core was used to keep track of
whether the DRBG has been instantiated.  Replace it with a boolean.

No functional change.

Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/crypto/drbg.c b/crypto/drbg.c
index 4f326385cf367758ae957ff4d3265a6c8e8af1f1..161070b10f85abb9d19759bcbb1e77c4e409f214 100644 (file)
--- a/crypto/drbg.c
+++ b/crypto/drbg.c
@@ -100,14 +100,6 @@
 #include <linux/string_choices.h>
 #include <linux/unaligned.h>
 
-struct drbg_state;
-
-struct drbg_core {
-       char cra_name[CRYPTO_MAX_ALG_NAME]; /* mapping to kernel crypto API */
-        /* kernel crypto API backend cipher name */
-       char backend_cra_name[CRYPTO_MAX_ALG_NAME];
-};
-
 enum drbg_seed_state {
        DRBG_SEED_STATE_UNSEEDED,
        DRBG_SEED_STATE_PARTIAL, /* Seeded with !rng_is_initialized() */
@@ -150,9 +142,9 @@ struct drbg_state {
        size_t reseed_threshold;
        enum drbg_seed_state seeded;            /* DRBG fully seeded? */
        unsigned long last_seed_time;
+       bool instantiated;
        bool pr;                /* Prediction resistance enabled? */
        struct crypto_rng *jent;
-       const struct drbg_core *core;
        struct drbg_string test_data;
 };
 
@@ -161,24 +153,6 @@ enum drbg_prefixes {
        DRBG_PREFIX1,
 };
 
-/***************************************************************
- * Backend cipher definitions available to DRBG
- ***************************************************************/
-
-/*
- * The order of the DRBG definitions here matter: every DRBG is registered
- * as stdrng. Each DRBG receives an increasing cra_priority values the later
- * they are defined in this array (see drbg_fill_array).
- *
- * Thus, the favored DRBGs are the latest entries in this array.
- */
-static const struct drbg_core drbg_cores[] = {
-       {
-               .cra_name = "hmac_sha512",
-               .backend_cra_name = "hmac(sha512)",
-       },
-};
-
 static int drbg_uninstantiate(struct drbg_state *drbg);
 
 /******************************************************************
@@ -455,7 +429,7 @@ static inline void drbg_dealloc_state(struct drbg_state *drbg)
        memzero_explicit(drbg->V, sizeof(drbg->V));
        memzero_explicit(drbg->C, sizeof(drbg->C));
        drbg->reseed_ctr = 0;
-       drbg->core = NULL;
+       drbg->instantiated = false;
 }
 
 /*
@@ -482,8 +456,8 @@ static int drbg_generate(struct drbg_state *drbg,
        int len = 0;
        LIST_HEAD(addtllist);
 
-       if (!drbg->core) {
-               pr_devel("DRBG: not yet seeded\n");
+       if (!drbg->instantiated) {
+               pr_devel("DRBG: not yet instantiated\n");
                return -EINVAL;
        }
        if (0 == buflen || !buf) {
@@ -625,7 +599,6 @@ static int drbg_prepare_hrng(struct drbg_state *drbg)
  *      the entropy is pulled by the DRBG internally unconditionally
  *      as defined in SP800-90A. The additional input is mixed into
  *      the state in addition to the pulled entropy.
- * @coreref reference to core
  * @pr prediction resistance enabled
  *
  * return
@@ -633,13 +606,13 @@ static int drbg_prepare_hrng(struct drbg_state *drbg)
  *     error value otherwise
  */
 static int drbg_instantiate(struct drbg_state *drbg, struct drbg_string *pers,
-                           int coreref, bool pr)
+                           bool pr)
 {
        int ret;
        bool reseed = true;
 
-       pr_devel("DRBG: Initializing DRBG core %d with prediction resistance "
-                "%s\n", coreref, str_enabled_disabled(pr));
+       pr_devel("DRBG: Initializing DRBG with prediction resistance %s\n",
+                str_enabled_disabled(pr));
        mutex_lock(&drbg->drbg_mutex);
 
        /* 9.1 step 1 is implicit with the selected DRBG type */
@@ -651,8 +624,8 @@ static int drbg_instantiate(struct drbg_state *drbg, struct drbg_string *pers,
 
        /* 9.1 step 4 is implicit in DRBG_SEC_STRENGTH */
 
-       if (!drbg->core) {
-               drbg->core = &drbg_cores[coreref];
+       if (!drbg->instantiated) {
+               drbg->instantiated = true;
                drbg->pr = pr;
                drbg->seeded = DRBG_SEED_STATE_UNSEEDED;
                drbg->last_seed_time = 0;
@@ -720,46 +693,6 @@ static void drbg_kcapi_set_entropy(struct crypto_rng *tfm,
  * Kernel crypto API interface to register DRBG
  ***************************************************************/
 
-/*
- * Look up the DRBG flags by given kernel crypto API cra_name
- * The code uses the drbg_cores definition to do this
- *
- * @cra_name kernel crypto API cra_name
- * @coreref reference to integer which is filled with the pointer to
- *  the applicable core
- * @pr reference for setting prediction resistance
- *
- * return: flags
- */
-static inline void drbg_convert_tfm_core(const char *cra_driver_name,
-                                        int *coreref, bool *pr)
-{
-       int i = 0;
-       size_t start = 0;
-       int len = 0;
-
-       *pr = true;
-       /* disassemble the names */
-       if (!memcmp(cra_driver_name, "drbg_nopr_", 10)) {
-               start = 10;
-               *pr = false;
-       } else if (!memcmp(cra_driver_name, "drbg_pr_", 8)) {
-               start = 8;
-       } else {
-               return;
-       }
-
-       /* remove the first part */
-       len = strlen(cra_driver_name) - start;
-       for (i = 0; ARRAY_SIZE(drbg_cores) > i; i++) {
-               if (!memcmp(cra_driver_name + start, drbg_cores[i].cra_name,
-                           len)) {
-                       *coreref = i;
-                       return;
-               }
-       }
-}
-
 static int drbg_kcapi_init(struct crypto_tfm *tfm)
 {
        struct drbg_state *drbg = crypto_tfm_ctx(tfm);
@@ -808,19 +741,17 @@ static int drbg_kcapi_seed(struct crypto_rng *tfm,
 {
        struct drbg_state *drbg = crypto_rng_ctx(tfm);
        struct crypto_tfm *tfm_base = crypto_rng_tfm(tfm);
-       bool pr = false;
+       bool pr = memcmp(crypto_tfm_alg_driver_name(tfm_base),
+                        "drbg_nopr_", 10) != 0;
        struct drbg_string string;
        struct drbg_string *seed_string = NULL;
-       int coreref = 0;
 
-       drbg_convert_tfm_core(crypto_tfm_alg_driver_name(tfm_base), &coreref,
-                             &pr);
        if (0 < slen) {
                drbg_string_fill(&string, seed, slen);
                seed_string = &string;
        }
 
-       return drbg_instantiate(drbg, seed_string, coreref, pr);
+       return drbg_instantiate(drbg, seed_string, pr);
 }
 
 /***************************************************************
@@ -844,22 +775,18 @@ static inline int __init drbg_healthcheck_sanity(void)
        struct drbg_state *drbg = NULL;
        int ret;
        int rc = -EFAULT;
-       bool pr = false;
-       int coreref = 0;
        struct drbg_string addtl;
 
        /* only perform test in FIPS mode */
        if (!fips_enabled)
                return 0;
 
-       drbg_convert_tfm_core("drbg_nopr_hmac_sha512", &coreref, &pr);
-
        drbg = kzalloc_obj(struct drbg_state);
        if (!drbg)
                return -ENOMEM;
 
        guard(mutex_init)(&drbg->drbg_mutex);
-       drbg->core = &drbg_cores[coreref];
+       drbg->instantiated = true;
        drbg->reseed_threshold = DRBG_MAX_REQUESTS;
 
        /*