diff options
| -rw-r--r-- | libcli/auth/credentials.c | 23 | ||||
| -rw-r--r-- | libcli/auth/proto.h | 1 |
2 files changed, 23 insertions, 1 deletions
diff --git a/libcli/auth/credentials.c b/libcli/auth/credentials.c index dbbef9e7a3c..64b424c099f 100644 --- a/libcli/auth/credentials.c +++ b/libcli/auth/credentials.c @@ -27,10 +27,31 @@ #include "../libcli/security/dom_sid.h" +bool netlogon_creds_is_random_challenge(const struct netr_Credential *challenge) +{ + /* + * If none of the first 5 bytes of the client challenge is unique, the + * server MUST fail session-key negotiation without further processing + * of the following steps. + */ + + if (challenge->data[1] == challenge->data[0] && + challenge->data[2] == challenge->data[0] && + challenge->data[3] == challenge->data[0] && + challenge->data[4] == challenge->data[0]) + { + return false; + } + + return true; +} + void netlogon_creds_random_challenge(struct netr_Credential *challenge) { ZERO_STRUCTP(challenge); - generate_random_buffer(challenge->data, sizeof(challenge->data)); + while (!netlogon_creds_is_random_challenge(challenge)) { + generate_random_buffer(challenge->data, sizeof(challenge->data)); + } } static void netlogon_creds_step_crypt(struct netlogon_creds_CredentialState *creds, diff --git a/libcli/auth/proto.h b/libcli/auth/proto.h index 82797d453ed..ad768682b9f 100644 --- a/libcli/auth/proto.h +++ b/libcli/auth/proto.h @@ -11,6 +11,7 @@ /* The following definitions come from /home/jeremy/src/samba/git/master/source3/../source4/../libcli/auth/credentials.c */ +bool netlogon_creds_is_random_challenge(const struct netr_Credential *challenge); void netlogon_creds_random_challenge(struct netr_Credential *challenge); void netlogon_creds_des_encrypt_LMKey(struct netlogon_creds_CredentialState *creds, struct netr_LMSessionKey *key); |