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-rw-r--r--crypto/drbg.c269
1 files changed, 184 insertions, 85 deletions
diff --git a/crypto/drbg.c b/crypto/drbg.c
index 0a3538f6cf22..f752da3a7c75 100644
--- a/crypto/drbg.c
+++ b/crypto/drbg.c
@@ -252,10 +252,16 @@ MODULE_ALIAS_CRYPTO("drbg_nopr_ctr_aes192");
MODULE_ALIAS_CRYPTO("drbg_pr_ctr_aes128");
MODULE_ALIAS_CRYPTO("drbg_nopr_ctr_aes128");
-static int drbg_kcapi_sym(struct drbg_state *drbg, const unsigned char *key,
- unsigned char *outval, const struct drbg_string *in);
+static void drbg_kcapi_symsetkey(struct drbg_state *drbg,
+ const unsigned char *key);
+static int drbg_kcapi_sym(struct drbg_state *drbg, unsigned char *outval,
+ const struct drbg_string *in);
static int drbg_init_sym_kernel(struct drbg_state *drbg);
static int drbg_fini_sym_kernel(struct drbg_state *drbg);
+static int drbg_kcapi_sym_ctr(struct drbg_state *drbg,
+ u8 *inbuf, u32 inbuflen,
+ u8 *outbuf, u32 outlen);
+#define DRBG_CTR_NULL_LEN 128
/* BCC function for CTR DRBG as defined in 10.4.3 */
static int drbg_ctr_bcc(struct drbg_state *drbg,
@@ -270,6 +276,7 @@ static int drbg_ctr_bcc(struct drbg_state *drbg,
drbg_string_fill(&data, out, drbg_blocklen(drbg));
/* 10.4.3 step 2 / 4 */
+ drbg_kcapi_symsetkey(drbg, key);
list_for_each_entry(curr, in, list) {
const unsigned char *pos = curr->buf;
size_t len = curr->len;
@@ -278,7 +285,7 @@ static int drbg_ctr_bcc(struct drbg_state *drbg,
/* 10.4.3 step 4.2 */
if (drbg_blocklen(drbg) == cnt) {
cnt = 0;
- ret = drbg_kcapi_sym(drbg, key, out, &data);
+ ret = drbg_kcapi_sym(drbg, out, &data);
if (ret)
return ret;
}
@@ -290,7 +297,7 @@ static int drbg_ctr_bcc(struct drbg_state *drbg,
}
/* 10.4.3 step 4.2 for last block */
if (cnt)
- ret = drbg_kcapi_sym(drbg, key, out, &data);
+ ret = drbg_kcapi_sym(drbg, out, &data);
return ret;
}
@@ -425,6 +432,7 @@ static int drbg_ctr_df(struct drbg_state *drbg,
/* 10.4.2 step 12: overwriting of outval is implemented in next step */
/* 10.4.2 step 13 */
+ drbg_kcapi_symsetkey(drbg, temp);
while (generated_len < bytes_to_return) {
short blocklen = 0;
/*
@@ -432,7 +440,7 @@ static int drbg_ctr_df(struct drbg_state *drbg,
* implicit as the key is only drbg_blocklen in size based on
* the implementation of the cipher function callback
*/
- ret = drbg_kcapi_sym(drbg, temp, X, &cipherin);
+ ret = drbg_kcapi_sym(drbg, X, &cipherin);
if (ret)
goto out;
blocklen = (drbg_blocklen(drbg) <
@@ -476,49 +484,47 @@ static int drbg_ctr_update(struct drbg_state *drbg, struct list_head *seed,
unsigned char *temp = drbg->scratchpad;
unsigned char *df_data = drbg->scratchpad + drbg_statelen(drbg) +
drbg_blocklen(drbg);
- unsigned char *temp_p, *df_data_p; /* pointer to iterate over buffers */
- unsigned int len = 0;
- struct drbg_string cipherin;
if (3 > reseed)
memset(df_data, 0, drbg_statelen(drbg));
- /* 10.2.1.3.2 step 2 and 10.2.1.4.2 step 2 */
- if (seed) {
- ret = drbg_ctr_df(drbg, df_data, drbg_statelen(drbg), seed);
+ if (!reseed) {
+ /*
+ * The DRBG uses the CTR mode of the underlying AES cipher. The
+ * CTR mode increments the counter value after the AES operation
+ * but SP800-90A requires that the counter is incremented before
+ * the AES operation. Hence, we increment it at the time we set
+ * it by one.
+ */
+ crypto_inc(drbg->V, drbg_blocklen(drbg));
+
+ ret = crypto_skcipher_setkey(drbg->ctr_handle, drbg->C,
+ drbg_keylen(drbg));
if (ret)
goto out;
}
- drbg_string_fill(&cipherin, drbg->V, drbg_blocklen(drbg));
- /*
- * 10.2.1.3.2 steps 2 and 3 are already covered as the allocation
- * zeroizes all memory during initialization
- */
- while (len < (drbg_statelen(drbg))) {
- /* 10.2.1.2 step 2.1 */
- crypto_inc(drbg->V, drbg_blocklen(drbg));
- /*
- * 10.2.1.2 step 2.2 */
- ret = drbg_kcapi_sym(drbg, drbg->C, temp + len, &cipherin);
+ /* 10.2.1.3.2 step 2 and 10.2.1.4.2 step 2 */
+ if (seed) {
+ ret = drbg_ctr_df(drbg, df_data, drbg_statelen(drbg), seed);
if (ret)
goto out;
- /* 10.2.1.2 step 2.3 and 3 */
- len += drbg_blocklen(drbg);
}
- /* 10.2.1.2 step 4 */
- temp_p = temp;
- df_data_p = df_data;
- for (len = 0; len < drbg_statelen(drbg); len++) {
- *temp_p ^= *df_data_p;
- df_data_p++; temp_p++;
- }
+ ret = drbg_kcapi_sym_ctr(drbg, df_data, drbg_statelen(drbg),
+ temp, drbg_statelen(drbg));
+ if (ret)
+ return ret;
/* 10.2.1.2 step 5 */
- memcpy(drbg->C, temp, drbg_keylen(drbg));
+ ret = crypto_skcipher_setkey(drbg->ctr_handle, temp,
+ drbg_keylen(drbg));
+ if (ret)
+ goto out;
/* 10.2.1.2 step 6 */
memcpy(drbg->V, temp + drbg_keylen(drbg), drbg_blocklen(drbg));
+ /* See above: increment counter by one to compensate timing of CTR op */
+ crypto_inc(drbg->V, drbg_blocklen(drbg));
ret = 0;
out:
@@ -537,9 +543,8 @@ static int drbg_ctr_generate(struct drbg_state *drbg,
unsigned char *buf, unsigned int buflen,
struct list_head *addtl)
{
- int len = 0;
- int ret = 0;
- struct drbg_string data;
+ int ret;
+ int len = min_t(int, buflen, INT_MAX);
/* 10.2.1.5.2 step 2 */
if (addtl && !list_empty(addtl)) {
@@ -549,33 +554,16 @@ static int drbg_ctr_generate(struct drbg_state *drbg,
}
/* 10.2.1.5.2 step 4.1 */
- crypto_inc(drbg->V, drbg_blocklen(drbg));
- drbg_string_fill(&data, drbg->V, drbg_blocklen(drbg));
- while (len < buflen) {
- int outlen = 0;
- /* 10.2.1.5.2 step 4.2 */
- ret = drbg_kcapi_sym(drbg, drbg->C, drbg->scratchpad, &data);
- if (ret) {
- len = ret;
- goto out;
- }
- outlen = (drbg_blocklen(drbg) < (buflen - len)) ?
- drbg_blocklen(drbg) : (buflen - len);
- /* 10.2.1.5.2 step 4.3 */
- memcpy(buf + len, drbg->scratchpad, outlen);
- len += outlen;
- /* 10.2.1.5.2 step 6 */
- if (len < buflen)
- crypto_inc(drbg->V, drbg_blocklen(drbg));
- }
+ ret = drbg_kcapi_sym_ctr(drbg, drbg->ctr_null_value, DRBG_CTR_NULL_LEN,
+ buf, len);
+ if (ret)
+ return ret;
/* 10.2.1.5.2 step 6 */
ret = drbg_ctr_update(drbg, NULL, 3);
if (ret)
len = ret;
-out:
- memset(drbg->scratchpad, 0, drbg_blocklen(drbg));
return len;
}
@@ -1145,11 +1133,11 @@ static inline void drbg_dealloc_state(struct drbg_state *drbg)
if (!drbg)
return;
kzfree(drbg->V);
- drbg->V = NULL;
+ drbg->Vbuf = NULL;
kzfree(drbg->C);
- drbg->C = NULL;
- kzfree(drbg->scratchpad);
- drbg->scratchpad = NULL;
+ drbg->Cbuf = NULL;
+ kzfree(drbg->scratchpadbuf);
+ drbg->scratchpadbuf = NULL;
drbg->reseed_ctr = 0;
drbg->d_ops = NULL;
drbg->core = NULL;
@@ -1185,12 +1173,18 @@ static inline int drbg_alloc_state(struct drbg_state *drbg)
goto err;
}
- drbg->V = kmalloc(drbg_statelen(drbg), GFP_KERNEL);
- if (!drbg->V)
- goto err;
- drbg->C = kmalloc(drbg_statelen(drbg), GFP_KERNEL);
- if (!drbg->C)
+ ret = drbg->d_ops->crypto_init(drbg);
+ if (ret < 0)
goto err;
+
+ drbg->Vbuf = kmalloc(drbg_statelen(drbg) + ret, GFP_KERNEL);
+ if (!drbg->Vbuf)
+ goto fini;
+ drbg->V = PTR_ALIGN(drbg->Vbuf, ret + 1);
+ drbg->Cbuf = kmalloc(drbg_statelen(drbg) + ret, GFP_KERNEL);
+ if (!drbg->Cbuf)
+ goto fini;
+ drbg->C = PTR_ALIGN(drbg->Cbuf, ret + 1);
/* scratchpad is only generated for CTR and Hash */
if (drbg->core->flags & DRBG_HMAC)
sb_size = 0;
@@ -1204,13 +1198,16 @@ static inline int drbg_alloc_state(struct drbg_state *drbg)
sb_size = drbg_statelen(drbg) + drbg_blocklen(drbg);
if (0 < sb_size) {
- drbg->scratchpad = kzalloc(sb_size, GFP_KERNEL);
- if (!drbg->scratchpad)
- goto err;
+ drbg->scratchpadbuf = kzalloc(sb_size + ret, GFP_KERNEL);
+ if (!drbg->scratchpadbuf)
+ goto fini;
+ drbg->scratchpad = PTR_ALIGN(drbg->scratchpadbuf, ret + 1);
}
return 0;
+fini:
+ drbg->d_ops->crypto_fini(drbg);
err:
drbg_dealloc_state(drbg);
return ret;
@@ -1478,10 +1475,6 @@ static int drbg_instantiate(struct drbg_state *drbg, struct drbg_string *pers,
if (ret)
goto unlock;
- ret = -EFAULT;
- if (drbg->d_ops->crypto_init(drbg))
- goto err;
-
ret = drbg_prepare_hrng(drbg);
if (ret)
goto free_everything;
@@ -1505,8 +1498,6 @@ static int drbg_instantiate(struct drbg_state *drbg, struct drbg_string *pers,
mutex_unlock(&drbg->drbg_mutex);
return ret;
-err:
- drbg_dealloc_state(drbg);
unlock:
mutex_unlock(&drbg->drbg_mutex);
return ret;
@@ -1591,7 +1582,8 @@ static int drbg_init_hash_kernel(struct drbg_state *drbg)
sdesc->shash.tfm = tfm;
sdesc->shash.flags = 0;
drbg->priv_data = sdesc;
- return 0;
+
+ return crypto_shash_alignmask(tfm);
}
static int drbg_fini_hash_kernel(struct drbg_state *drbg)
@@ -1627,10 +1619,45 @@ static int drbg_kcapi_hash(struct drbg_state *drbg, unsigned char *outval,
#endif /* (CONFIG_CRYPTO_DRBG_HASH || CONFIG_CRYPTO_DRBG_HMAC) */
#ifdef CONFIG_CRYPTO_DRBG_CTR
+static int drbg_fini_sym_kernel(struct drbg_state *drbg)
+{
+ struct crypto_cipher *tfm =
+ (struct crypto_cipher *)drbg->priv_data;
+ if (tfm)
+ crypto_free_cipher(tfm);
+ drbg->priv_data = NULL;
+
+ if (drbg->ctr_handle)
+ crypto_free_skcipher(drbg->ctr_handle);
+ drbg->ctr_handle = NULL;
+
+ if (drbg->ctr_req)
+ skcipher_request_free(drbg->ctr_req);
+ drbg->ctr_req = NULL;
+
+ kfree(drbg->ctr_null_value_buf);
+ drbg->ctr_null_value = NULL;
+
+ return 0;
+}
+
+static void drbg_skcipher_cb(struct crypto_async_request *req, int error)
+{
+ struct drbg_state *drbg = req->data;
+
+ if (error == -EINPROGRESS)
+ return;
+ drbg->ctr_async_err = error;
+ complete(&drbg->ctr_completion);
+}
+
static int drbg_init_sym_kernel(struct drbg_state *drbg)
{
- int ret = 0;
struct crypto_cipher *tfm;
+ struct crypto_skcipher *sk_tfm;
+ struct skcipher_request *req;
+ unsigned int alignmask;
+ char ctr_name[CRYPTO_MAX_ALG_NAME];
tfm = crypto_alloc_cipher(drbg->core->backend_cra_name, 0, 0);
if (IS_ERR(tfm)) {
@@ -1640,31 +1667,103 @@ static int drbg_init_sym_kernel(struct drbg_state *drbg)
}
BUG_ON(drbg_blocklen(drbg) != crypto_cipher_blocksize(tfm));
drbg->priv_data = tfm;
- return ret;
+
+ if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)",
+ drbg->core->backend_cra_name) >= CRYPTO_MAX_ALG_NAME) {
+ drbg_fini_sym_kernel(drbg);
+ return -EINVAL;
+ }
+ sk_tfm = crypto_alloc_skcipher(ctr_name, 0, 0);
+ if (IS_ERR(sk_tfm)) {
+ pr_info("DRBG: could not allocate CTR cipher TFM handle: %s\n",
+ ctr_name);
+ drbg_fini_sym_kernel(drbg);
+ return PTR_ERR(sk_tfm);
+ }
+ drbg->ctr_handle = sk_tfm;
+
+ req = skcipher_request_alloc(sk_tfm, GFP_KERNEL);
+ if (!req) {
+ pr_info("DRBG: could not allocate request queue\n");
+ drbg_fini_sym_kernel(drbg);
+ return -ENOMEM;
+ }
+ drbg->ctr_req = req;
+ skcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
+ drbg_skcipher_cb, drbg);
+
+ alignmask = crypto_skcipher_alignmask(sk_tfm);
+ drbg->ctr_null_value_buf = kzalloc(DRBG_CTR_NULL_LEN + alignmask,
+ GFP_KERNEL);
+ if (!drbg->ctr_null_value_buf) {
+ drbg_fini_sym_kernel(drbg);
+ return -ENOMEM;
+ }
+ drbg->ctr_null_value = (u8 *)PTR_ALIGN(drbg->ctr_null_value_buf,
+ alignmask + 1);
+
+ return alignmask;
}
-static int drbg_fini_sym_kernel(struct drbg_state *drbg)
+static void drbg_kcapi_symsetkey(struct drbg_state *drbg,
+ const unsigned char *key)
{
struct crypto_cipher *tfm =
(struct crypto_cipher *)drbg->priv_data;
- if (tfm)
- crypto_free_cipher(tfm);
- drbg->priv_data = NULL;
- return 0;
+
+ crypto_cipher_setkey(tfm, key, (drbg_keylen(drbg)));
}
-static int drbg_kcapi_sym(struct drbg_state *drbg, const unsigned char *key,
- unsigned char *outval, const struct drbg_string *in)
+static int drbg_kcapi_sym(struct drbg_state *drbg, unsigned char *outval,
+ const struct drbg_string *in)
{
struct crypto_cipher *tfm =
(struct crypto_cipher *)drbg->priv_data;
- crypto_cipher_setkey(tfm, key, (drbg_keylen(drbg)));
/* there is only component in *in */
BUG_ON(in->len < drbg_blocklen(drbg));
crypto_cipher_encrypt_one(tfm, outval, in->buf);
return 0;
}
+
+static int drbg_kcapi_sym_ctr(struct drbg_state *drbg,
+ u8 *inbuf, u32 inlen,
+ u8 *outbuf, u32 outlen)
+{
+ struct scatterlist sg_in;
+
+ sg_init_one(&sg_in, inbuf, inlen);
+
+ while (outlen) {
+ u32 cryptlen = min_t(u32, inlen, outlen);
+ struct scatterlist sg_out;
+ int ret;
+
+ sg_init_one(&sg_out, outbuf, cryptlen);
+ skcipher_request_set_crypt(drbg->ctr_req, &sg_in, &sg_out,
+ cryptlen, drbg->V);
+ ret = crypto_skcipher_encrypt(drbg->ctr_req);
+ switch (ret) {
+ case 0:
+ break;
+ case -EINPROGRESS:
+ case -EBUSY:
+ ret = wait_for_completion_interruptible(
+ &drbg->ctr_completion);
+ if (!ret && !drbg->ctr_async_err) {
+ reinit_completion(&drbg->ctr_completion);
+ break;
+ }
+ default:
+ return ret;
+ }
+ init_completion(&drbg->ctr_completion);
+
+ outlen -= cryptlen;
+ }
+
+ return 0;
+}
#endif /* CONFIG_CRYPTO_DRBG_CTR */
/***************************************************************
generated by cgit v1.2.3 (git 2.0.4) at 2024-05-31 10:08:54 +0000