diff options
Diffstat (limited to 'crypto/bn/bn_exp.c')
| -rw-r--r-- | crypto/bn/bn_exp.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/crypto/bn/bn_exp.c b/crypto/bn/bn_exp.c index d9b6c737fc..2e1e4e7fd8 100644 --- a/crypto/bn/bn_exp.c +++ b/crypto/bn/bn_exp.c @@ -767,7 +767,14 @@ int BN_mod_exp_mont_word(BIGNUM *rr, BN_ULONG a, const BIGNUM *p, bits = BN_num_bits(p); if (bits == 0) { - ret = BN_one(rr); + /* x**0 mod 1 is still zero. */ + if (BN_is_one(m)) + { + ret = 1; + BN_zero(rr); + } + else + ret = BN_one(rr); return ret; } if (a == 0) |