Commit 1648338b authored by Dr. Matthias St. Pierre's avatar Dr. Matthias St. Pierre
Browse files

Fix size limitation of RAND_DRBG_bytes() 



When comparing the implementations of drbg_bytes() and RAND_DRBG_bytes(),
it was noticed that the former split the buffer into chunks when calling
RAND_DRBG_generate() to circumvent the size limitation of the buffer
to outlen <= drb->max_request. This loop was missing in RAND_DRBG_bytes(),
so it was adopted from drbg_bytes().

Reviewed-by: default avatarKurt Roeckx <kurt@roeckx.be>
(Merged from https://github.com/openssl/openssl/pull/5251)
parent 58351fbd

crypto/rand/drbg_lib.c

+13 −1
Original line number Diff line number Diff line
@@ -546,10 +546,22 @@ int RAND_DRBG_bytes(RAND_DRBG *drbg, unsigned char *out, size_t outlen) 
{

    unsigned char *additional = NULL;

    size_t additional_len;

    size_t chunk;

    size_t ret;



    additional_len = rand_drbg_get_additional_data(&additional, drbg->max_adinlen);

    ret = RAND_DRBG_generate(drbg, out, outlen, 0, additional, additional_len);



    for ( ; outlen > 0; outlen -= chunk, out += chunk) {

        chunk = outlen;

        if (chunk > drbg->max_request)

            chunk = drbg->max_request;

        ret = RAND_DRBG_generate(drbg, out, chunk, 0, additional, additional_len);

        if (!ret)

            goto err;

    }

    ret = 1;



err:

    if (additional_len != 0)

        OPENSSL_secure_clear_free(additional, additional_len);