commit 0034f1095680e2b05c19ec13368ddc936a53058a Author: Nick Mathewson nickm@torproject.org Date: Tue Apr 30 14:45:58 2019 -0400
Use safe_mem_is_zero in a few more places.
I don't believe any of these represent a real timing vulnerability (remote timing against memcmp() on a modern CPU is not easy), but these are the ones where I believe we should be more careful. --- src/feature/relay/routerkeys.c | 2 +- src/feature/rend/rendcache.c | 6 ++++-- src/lib/crypt_ops/crypto_ed25519.c | 2 +- src/lib/crypt_ops/crypto_rand.c | 3 ++- 4 files changed, 8 insertions(+), 5 deletions(-)
diff --git a/src/feature/relay/routerkeys.c b/src/feature/relay/routerkeys.c index 5db7ed726..a9190b2e1 100644 --- a/src/feature/relay/routerkeys.c +++ b/src/feature/relay/routerkeys.c @@ -226,7 +226,7 @@ load_ed_keys(const or_options_t *options, time_t now) tor_free(fname); } } - if (tor_mem_is_zero((char*)id->seckey.seckey, sizeof(id->seckey))) + if (safe_mem_is_zero((char*)id->seckey.seckey, sizeof(id->seckey))) sign_signing_key_with_id = NULL; else sign_signing_key_with_id = id; diff --git a/src/feature/rend/rendcache.c b/src/feature/rend/rendcache.c index abeb15068..c3f86d8c8 100644 --- a/src/feature/rend/rendcache.c +++ b/src/feature/rend/rendcache.c @@ -19,6 +19,8 @@ #include "feature/rend/rend_intro_point_st.h" #include "feature/rend/rend_service_descriptor_st.h"
+#include "lib/ctime/di_ops.h" + /** Map from service id (as generated by rend_get_service_id) to * rend_cache_entry_t. */ STATIC strmap_t *rend_cache = NULL; @@ -889,8 +891,8 @@ rend_cache_store_v2_desc_as_client(const char *desc, if (intro_content && intro_size > 0) { int n_intro_points; if (rend_data->auth_type != REND_NO_AUTH && - !tor_mem_is_zero(rend_data->descriptor_cookie, - sizeof(rend_data->descriptor_cookie))) { + !safe_mem_is_zero(rend_data->descriptor_cookie, + sizeof(rend_data->descriptor_cookie))) { char *ipos_decrypted = NULL; size_t ipos_decrypted_size; if (rend_decrypt_introduction_points(&ipos_decrypted, diff --git a/src/lib/crypt_ops/crypto_ed25519.c b/src/lib/crypt_ops/crypto_ed25519.c index 400f96389..058152912 100644 --- a/src/lib/crypt_ops/crypto_ed25519.c +++ b/src/lib/crypt_ops/crypto_ed25519.c @@ -226,7 +226,7 @@ ed25519_keypair_generate(ed25519_keypair_t *keypair_out, int extra_strong) int ed25519_public_key_is_zero(const ed25519_public_key_t *pubkey) { - return tor_mem_is_zero((char*)pubkey->pubkey, ED25519_PUBKEY_LEN); + return safe_mem_is_zero((char*)pubkey->pubkey, ED25519_PUBKEY_LEN); }
/* Return a heap-allocated array that contains <b>msg</b> prefixed by the diff --git a/src/lib/crypt_ops/crypto_rand.c b/src/lib/crypt_ops/crypto_rand.c index 0b1cb96c1..79c8ed1ee 100644 --- a/src/lib/crypt_ops/crypto_rand.c +++ b/src/lib/crypt_ops/crypto_rand.c @@ -36,6 +36,7 @@
#include "lib/defs/digest_sizes.h" #include "lib/crypt_ops/crypto_digest.h" +#include "lib/ctime/di_ops.h"
#ifdef ENABLE_NSS #include "lib/crypt_ops/crypto_nss_mgt.h" @@ -314,7 +315,7 @@ crypto_strongest_rand_raw(uint8_t *out, size_t out_len) } }
- if ((out_len < sanity_min_size) || !tor_mem_is_zero((char*)out, out_len)) + if ((out_len < sanity_min_size) || !safe_mem_is_zero((char*)out, out_len)) return 0; }