crypto: jitterentropy - change back to module_init()

[linux.git] / crypto / drbg.c

diff --git a/crypto/drbg.c b/crypto/drbg.c
index 466a112a4446820ff655c3b72076c86d3c7e4f2d..2a5b16bb000c384e90c7de620efd71db35995324 100644 (file)
--- a/crypto/drbg.c
+++ b/crypto/drbg.c
@@ -261,8 +261,7 @@ 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
-#define DRBG_OUTSCRATCHLEN DRBG_CTR_NULL_LEN
+#define DRBG_OUTSCRATCHLEN 256
 
 /* BCC function for CTR DRBG as defined in 10.4.3 */
 static int drbg_ctr_bcc(struct drbg_state *drbg,
@@ -555,8 +554,7 @@ static int drbg_ctr_generate(struct drbg_state *drbg,
        }
 
        /* 10.2.1.5.2 step 4.1 */
-       ret = drbg_kcapi_sym_ctr(drbg, drbg->ctr_null_value, DRBG_CTR_NULL_LEN,
-                                buf, len);
+       ret = drbg_kcapi_sym_ctr(drbg, NULL, 0, buf, len);
        if (ret)
                return ret;
 
@@ -1589,7 +1587,6 @@ static int drbg_init_hash_kernel(struct drbg_state *drbg)
        }
 
        sdesc->shash.tfm = tfm;
-       sdesc->shash.flags = 0;
        drbg->priv_data = sdesc;
 
        return crypto_shash_alignmask(tfm);
@@ -1644,9 +1641,6 @@ static int drbg_fini_sym_kernel(struct drbg_state *drbg)
                skcipher_request_free(drbg->ctr_req);
        drbg->ctr_req = NULL;
 
-       kfree(drbg->ctr_null_value_buf);
-       drbg->ctr_null_value = NULL;
-
        kfree(drbg->outscratchpadbuf);
        drbg->outscratchpadbuf = NULL;
 
@@ -1697,15 +1691,6 @@ static int drbg_init_sym_kernel(struct drbg_state *drbg)
                                        crypto_req_done, &drbg->ctr_wait);
 
        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);
-
        drbg->outscratchpadbuf = kmalloc(DRBG_OUTSCRATCHLEN + alignmask,
                                         GFP_KERNEL);
        if (!drbg->outscratchpadbuf) {
@@ -1715,6 +1700,9 @@ static int drbg_init_sym_kernel(struct drbg_state *drbg)
        drbg->outscratchpad = (u8 *)PTR_ALIGN(drbg->outscratchpadbuf,
                                              alignmask + 1);
 
+       sg_init_table(&drbg->sg_in, 1);
+       sg_init_one(&drbg->sg_out, drbg->outscratchpad, DRBG_OUTSCRATCHLEN);
+
        return alignmask;
 }
 
@@ -1743,17 +1731,25 @@ static int drbg_kcapi_sym_ctr(struct drbg_state *drbg,
                              u8 *inbuf, u32 inlen,
                              u8 *outbuf, u32 outlen)
 {
-       struct scatterlist sg_in, sg_out;
+       struct scatterlist *sg_in = &drbg->sg_in, *sg_out = &drbg->sg_out;
+       u32 scratchpad_use = min_t(u32, outlen, DRBG_OUTSCRATCHLEN);
        int ret;
 
-       sg_init_one(&sg_in, inbuf, inlen);
-       sg_init_one(&sg_out, drbg->outscratchpad, DRBG_OUTSCRATCHLEN);
+       if (inbuf) {
+               /* Use caller-provided input buffer */
+               sg_set_buf(sg_in, inbuf, inlen);
+       } else {
+               /* Use scratchpad for in-place operation */
+               inlen = scratchpad_use;
+               memset(drbg->outscratchpad, 0, scratchpad_use);
+               sg_set_buf(sg_in, drbg->outscratchpad, scratchpad_use);
+       }
 
        while (outlen) {
                u32 cryptlen = min3(inlen, outlen, (u32)DRBG_OUTSCRATCHLEN);
 
                /* Output buffer may not be valid for SGL, use scratchpad */
-               skcipher_request_set_crypt(drbg->ctr_req, &sg_in, &sg_out,
+               skcipher_request_set_crypt(drbg->ctr_req, sg_in, sg_out,
                                           cryptlen, drbg->V);
                ret = crypto_wait_req(crypto_skcipher_encrypt(drbg->ctr_req),
                                        &drbg->ctr_wait);
@@ -1763,6 +1759,7 @@ static int drbg_kcapi_sym_ctr(struct drbg_state *drbg,
                crypto_init_wait(&drbg->ctr_wait);
 
                memcpy(outbuf, drbg->outscratchpad, cryptlen);
+               memzero_explicit(drbg->outscratchpad, cryptlen);
 
                outlen -= cryptlen;
                outbuf += cryptlen;
@@ -1770,7 +1767,6 @@ static int drbg_kcapi_sym_ctr(struct drbg_state *drbg,
        ret = 0;
 
 out:
-       memzero_explicit(drbg->outscratchpad, DRBG_OUTSCRATCHLEN);
        return ret;
 }
 #endif /* CONFIG_CRYPTO_DRBG_CTR */
@@ -2042,7 +2038,7 @@ static void __exit drbg_exit(void)
        crypto_unregister_rngs(drbg_algs, (ARRAY_SIZE(drbg_cores) * 2));
 }
 
-module_init(drbg_init);
+subsys_initcall(drbg_init);
 module_exit(drbg_exit);
 #ifndef CRYPTO_DRBG_HASH_STRING
 #define CRYPTO_DRBG_HASH_STRING ""