diff options
Diffstat (limited to 'crypto/drbg.c')
| -rw-r--r-- | crypto/drbg.c | 29 |
1 files changed, 24 insertions, 5 deletions
diff --git a/crypto/drbg.c b/crypto/drbg.c index fb33f7d3b052..053035b5c8f8 100644 --- a/crypto/drbg.c +++ b/crypto/drbg.c @@ -262,6 +262,7 @@ 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 /* BCC function for CTR DRBG as defined in 10.4.3 */ static int drbg_ctr_bcc(struct drbg_state *drbg, @@ -1644,6 +1645,9 @@ static int drbg_fini_sym_kernel(struct drbg_state *drbg) kfree(drbg->ctr_null_value_buf); drbg->ctr_null_value = NULL; + kfree(drbg->outscratchpadbuf); + drbg->outscratchpadbuf = NULL; + return 0; } @@ -1708,6 +1712,15 @@ static int drbg_init_sym_kernel(struct drbg_state *drbg) 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) { + drbg_fini_sym_kernel(drbg); + return -ENOMEM; + } + drbg->outscratchpad = (u8 *)PTR_ALIGN(drbg->outscratchpadbuf, + alignmask + 1); + return alignmask; } @@ -1737,15 +1750,16 @@ static int drbg_kcapi_sym_ctr(struct drbg_state *drbg, u8 *outbuf, u32 outlen) { struct scatterlist sg_in; + int ret; sg_init_one(&sg_in, inbuf, inlen); while (outlen) { - u32 cryptlen = min_t(u32, inlen, outlen); + u32 cryptlen = min3(inlen, outlen, (u32)DRBG_OUTSCRATCHLEN); struct scatterlist sg_out; - int ret; - sg_init_one(&sg_out, outbuf, cryptlen); + /* Output buffer may not be valid for SGL, use scratchpad */ + sg_init_one(&sg_out, drbg->outscratchpad, cryptlen); skcipher_request_set_crypt(drbg->ctr_req, &sg_in, &sg_out, cryptlen, drbg->V); ret = crypto_skcipher_encrypt(drbg->ctr_req); @@ -1761,14 +1775,19 @@ static int drbg_kcapi_sym_ctr(struct drbg_state *drbg, break; } default: - return ret; + goto out; } init_completion(&drbg->ctr_completion); + memcpy(outbuf, drbg->outscratchpad, cryptlen); + outlen -= cryptlen; } + ret = 0; - return 0; +out: + memzero_explicit(drbg->outscratchpad, DRBG_OUTSCRATCHLEN); + return ret; } #endif /* CONFIG_CRYPTO_DRBG_CTR */ |