diff options
Diffstat (limited to 'crypto/drbg.c')
| -rw-r--r-- | crypto/drbg.c | 34 |
1 files changed, 14 insertions, 20 deletions
diff --git a/crypto/drbg.c b/crypto/drbg.c index ee302fd229ad..bc52d9562611 100644 --- 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; @@ -1644,9 +1642,6 @@ 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 +1692,6 @@ 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) { @@ -1716,7 +1702,7 @@ static int drbg_init_sym_kernel(struct drbg_state *drbg) alignmask + 1); sg_init_table(&drbg->sg_in, 1); - sg_init_table(&drbg->sg_out, 1); + sg_init_one(&drbg->sg_out, drbg->outscratchpad, DRBG_OUTSCRATCHLEN); return alignmask; } @@ -1747,10 +1733,18 @@ static int drbg_kcapi_sym_ctr(struct drbg_state *drbg, u8 *outbuf, u32 outlen) { struct scatterlist *sg_in = &drbg->sg_in, *sg_out = &drbg->sg_out; + u32 scratchpad_use = min_t(u32, outlen, DRBG_OUTSCRATCHLEN); int ret; - sg_set_buf(sg_in, inbuf, inlen); - sg_set_buf(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); @@ -1766,6 +1760,7 @@ 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; @@ -1773,7 +1768,6 @@ 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 */ |