diff options
author | Emilia Kasper <emilia@openssl.org> | 2014-08-25 12:38:16 +0200 |
---|---|---|
committer | Emilia Kasper <emilia@openssl.org> | 2014-08-27 19:49:35 +0200 |
commit | f34a57202be4a5d3786ba65ad88d760aa02630f0 (patch) | |
tree | 46cbefa09df385743baa38a3a09f56c6ec41e3d1 /crypto/ec/ec_asn1.c | |
parent | f063e30fe9f316067950bdf0397b51cf87d4b6a6 (diff) |
Explicitly check for empty ASN.1 strings in d2i_ECPrivateKey
The old code implicitly relies on the ASN.1 code returning a \0-prefixed buffer
when the buffer length is 0. Change this to verify explicitly that the ASN.1 string
has positive length.
Reviewed-by: Dr Stephen Henson <steve@openssl.org>
Diffstat (limited to 'crypto/ec/ec_asn1.c')
-rw-r--r-- | crypto/ec/ec_asn1.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/crypto/ec/ec_asn1.c b/crypto/ec/ec_asn1.c index 26d6360454..52d31c2f96 100644 --- a/crypto/ec/ec_asn1.c +++ b/crypto/ec/ec_asn1.c @@ -1195,14 +1195,20 @@ EC_KEY *d2i_ECPrivateKey(EC_KEY **a, const unsigned char **in, long len) if (priv_key->publicKey) { const unsigned char *pub_oct; - size_t pub_oct_len; + int pub_oct_len; pub_oct = M_ASN1_STRING_data(priv_key->publicKey); pub_oct_len = M_ASN1_STRING_length(priv_key->publicKey); - /* save the point conversion form */ + /* The first byte - point conversion form - must be present. */ + if (pub_oct_len <= 0) + { + ECerr(EC_F_D2I_ECPRIVATEKEY, EC_R_BUFFER_TOO_SMALL); + goto err; + } + /* Save the point conversion form. */ ret->conv_form = (point_conversion_form_t)(pub_oct[0] & ~0x01); if (!EC_POINT_oct2point(ret->group, ret->pub_key, - pub_oct, pub_oct_len, NULL)) + pub_oct, (size_t)(pub_oct_len), NULL)) { ECerr(EC_F_D2I_ECPRIVATEKEY, ERR_R_EC_LIB); goto err; |