diff options
Diffstat (limited to 'dirmngr/crlcache.c')
| -rw-r--r-- | dirmngr/crlcache.c | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/dirmngr/crlcache.c b/dirmngr/crlcache.c index d508e173f..fe96b11b2 100644 --- a/dirmngr/crlcache.c +++ b/dirmngr/crlcache.c @@ -1660,6 +1660,7 @@ finish_sig_check (ksba_crl_t crl, gcry_md_hd_t md, int algo, size_t n; gcry_sexp_t s_sig = NULL, s_hash = NULL, s_pkey = NULL; unsigned int saltlen = 0; /* (used only with use_pss) */ + int pkalgo; /* This also stops debugging on the MD. */ gcry_md_final (md); @@ -1787,6 +1788,53 @@ finish_sig_check (ksba_crl_t crl, gcry_md_hd_t md, int algo, gcry_md_read (md, algo), saltlen); } + else if ((pkalgo = pk_algo_from_sexp (s_pkey)) == GCRY_PK_ECC) + { + unsigned int qbits0, qbits; + + qbits0 = gcry_pk_get_nbits (s_pkey); + qbits = qbits0 == 521? 512 : qbits0; + + if ((qbits%8)) + { + log_error ("ECDSA requires the hash length to be a" + " multiple of 8 bits\n"); + err = gpg_error (GPG_ERR_INTERNAL); + goto leave; + } + + /* Don't allow any Q smaller than 160 bits. */ + if (qbits < 160) + { + log_error (_("%s key uses an unsafe (%u bit) hash\n"), + gcry_pk_algo_name (pkalgo), qbits0); + err = gpg_error (GPG_ERR_INTERNAL); + goto leave; + } + + /* Check if we're too short. */ + n = gcry_md_get_algo_dlen (algo); + if (n < qbits/8) + { + log_error (_("a %u bit hash is not valid for a %u bit %s key\n"), + (unsigned int)n*8, + qbits0, + gcry_pk_algo_name (pkalgo)); + if (n < 20) + { + err = gpg_error (GPG_ERR_INTERNAL); + goto leave; + } + } + + /* Truncate. */ + if (n > qbits/8) + n = qbits/8; + + err = gcry_sexp_build (&s_hash, NULL, "%b", + (int)n, + gcry_md_read (md, algo)); + } else { err = gcry_sexp_build (&s_hash, NULL, |