diff options
Diffstat (limited to 'net/sunrpc/auth_gss/auth_gss.c')
| -rw-r--r-- | net/sunrpc/auth_gss/auth_gss.c | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c index 2d7b1e03110a..1af71fbb0d80 100644 --- a/net/sunrpc/auth_gss/auth_gss.c +++ b/net/sunrpc/auth_gss/auth_gss.c @@ -49,6 +49,22 @@ static unsigned int gss_key_expire_timeo = GSS_KEY_EXPIRE_TIMEO; # define RPCDBG_FACILITY RPCDBG_AUTH #endif +/* + * This compile-time check verifies that we will not exceed the + * slack space allotted by the client and server auth_gss code + * before they call gss_wrap(). + */ +#define GSS_KRB5_MAX_SLACK_NEEDED \ + (GSS_KRB5_TOK_HDR_LEN /* gss token header */ \ + + GSS_KRB5_MAX_CKSUM_LEN /* gss token checksum */ \ + + GSS_KRB5_MAX_BLOCKSIZE /* confounder */ \ + + GSS_KRB5_MAX_BLOCKSIZE /* possible padding */ \ + + GSS_KRB5_TOK_HDR_LEN /* encrypted hdr in v2 token */ \ + + GSS_KRB5_MAX_CKSUM_LEN /* encryption hmac */ \ + + XDR_UNIT * 2 /* RPC verifier */ \ + + GSS_KRB5_TOK_HDR_LEN \ + + GSS_KRB5_MAX_CKSUM_LEN) + #define GSS_CRED_SLACK (RPC_MAX_AUTH_SIZE * 2) /* length of a krb5 verifier (48), plus data added before arguments when * using integrity (two 4-byte integers): */ @@ -1042,6 +1058,7 @@ gss_create_new(const struct rpc_auth_create_args *args, struct rpc_clnt *clnt) goto err_put_mech; auth = &gss_auth->rpc_auth; auth->au_cslack = GSS_CRED_SLACK >> 2; + BUILD_BUG_ON(GSS_KRB5_MAX_SLACK_NEEDED > RPC_MAX_AUTH_SIZE); auth->au_rslack = GSS_KRB5_MAX_SLACK_NEEDED >> 2; auth->au_verfsize = GSS_VERF_SLACK >> 2; auth->au_ralign = GSS_VERF_SLACK >> 2; |