From 054f6180d8b5602b431b5924976c956e760488b1 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 1 Dec 2014 22:52:50 +0000 Subject: KEYS: Simplify KEYRING_SEARCH_{NO,DO}_STATE_CHECK flags Simplify KEYRING_SEARCH_{NO,DO}_STATE_CHECK flags to be two variations of the same flag. They are effectively mutually exclusive and one or the other should be provided, but not both. Keyring cycle detection and key possession determination are the only things that set NO_STATE_CHECK, except that neither flag really does anything there because neither purpose makes use of the keyring_search_iterator() function, but rather provides their own. For cycle detection we definitely want to check inside of expired keyrings, just so that we don't create a cycle we can't get rid of. Revoked keyrings are cleared at revocation time and can't then be reused, so shouldn't be a problem either way. For possession determination, we *might* want to validate each keyring before searching it: do you possess a key that's hidden behind an expired or just plain inaccessible keyring? Currently, the answer is yes. Note that you cannot, however, possess a key behind a revoked keyring because they are cleared on revocation. keyring_search() sets DO_STATE_CHECK, which is correct. request_key_and_link() currently doesn't specify whether to check the key state or not - but it should set DO_STATE_CHECK. key_get_instantiation_authkey() also currently doesn't specify whether to check the key state or not - but it probably should also set DO_STATE_CHECK. Signed-off-by: David Howells Tested-by: Chuck Lever --- security/keys/keyring.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'security/keys/keyring.c') diff --git a/security/keys/keyring.c b/security/keys/keyring.c index 8177010174f7..238aa172f25b 100644 --- a/security/keys/keyring.c +++ b/security/keys/keyring.c @@ -628,6 +628,10 @@ static bool search_nested_keyrings(struct key *keyring, ctx->index_key.type->name, ctx->index_key.description); +#define STATE_CHECKS (KEYRING_SEARCH_NO_STATE_CHECK | KEYRING_SEARCH_DO_STATE_CHECK) + BUG_ON((ctx->flags & STATE_CHECKS) == 0 || + (ctx->flags & STATE_CHECKS) == STATE_CHECKS); + if (ctx->index_key.description) ctx->index_key.desc_len = strlen(ctx->index_key.description); @@ -637,7 +641,6 @@ static bool search_nested_keyrings(struct key *keyring, if (ctx->match_data.lookup_type == KEYRING_SEARCH_LOOKUP_ITERATE || keyring_compare_object(keyring, &ctx->index_key)) { ctx->skipped_ret = 2; - ctx->flags |= KEYRING_SEARCH_DO_STATE_CHECK; switch (ctx->iterator(keyring_key_to_ptr(keyring), ctx)) { case 1: goto found; @@ -649,8 +652,6 @@ static bool search_nested_keyrings(struct key *keyring, } ctx->skipped_ret = 0; - if (ctx->flags & KEYRING_SEARCH_NO_STATE_CHECK) - ctx->flags &= ~KEYRING_SEARCH_DO_STATE_CHECK; /* Start processing a new keyring */ descend_to_keyring: -- cgit v1.2.3