Mercurial > dropbear
changeset 1410:771e4a7051e0
improve value range validation
| author | Matt Johnston <matt@ucc.asn.au> |
|---|---|
| date | Wed, 14 Jun 2017 23:31:15 +0800 |
| parents | c721e8c42d2a |
| children | 798854f62430 a54b22f4058d |
| files | dss.c |
| diffstat | 1 files changed, 8 insertions(+), 0 deletions(-) [+] |
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--- a/dss.c Fri May 26 21:08:43 2017 +0800 +++ b/dss.c Wed Jun 14 23:31:15 2017 +0800 @@ -181,6 +181,10 @@ TRACE(("verify failed, s' >= q")) goto out; } + if (mp_cmp_d(&val1, 0) != MP_GT) { + TRACE(("verify failed, s' <= 0")) + goto out; + } /* let val2 = w = (s')^-1 mod q*/ if (mp_invmod(&val1, key->q, &val2) != MP_OKAY) { goto out; @@ -202,6 +206,10 @@ TRACE(("verify failed, r' >= q")) goto out; } + if (mp_cmp_d(&val1, 0) != MP_GT) { + TRACE(("verify failed, r' <= 0")) + goto out; + } /* let val4 = u2 = ((r')w) mod q */ if (mp_mulmod(&val1, &val2, key->q, &val4) != MP_OKAY) { goto out;