Use TargetName from the challenge msg if no domain is given

If were not given an explicit domain name, use the target name
from teh challenge message and update the domain of both smb2 context
as well as the ntlmssp auth_data.

Signed-off-by: Ronnie Sahlberg <[email protected]>

lib/ntlmssp.c

@@ -94,6 +94,7 @@ struct auth_data {
         char *password;
         char *domain;
         char *workstation;
+        char *target_name;
         uint8_t *client_challenge;
         uint8_t server_challenge[8];
         uint8_t *target_info;
@@ -130,6 +131,7 @@ ntlmssp_destroy_context(struct auth_data *auth)
         free(auth->password);
         free(auth->domain);
         free(auth->workstation);
+        free(auth->target_name);
         free(auth->client_challenge);
         free(auth->target_info);
         free(auth);
@@ -338,6 +340,7 @@ ntlm_decode_challenge_message(struct smb2_context *smb2, struct auth_data *auth_
                 memcpy(&auth_data->ntlm_buf[16], &u32, 4);
 
                 if (inlen > 0 && inlen < len && (outoff + inlen) < alloc_len) {
+                        auth_data->target_name = discard_const(smb2_utf16_to_utf8((const uint16_t *)&buf[inoff], inlen / 2));
                         memcpy(&auth_data->ntlm_buf[outoff], &buf[inoff], inlen);
                         outoff += inlen;
                 }
@@ -360,7 +363,6 @@ ntlm_decode_challenge_message(struct smb2_context *smb2, struct auth_data *auth_
                                 attr_code = htole16(u16);
                                 memcpy(&u16, &buf[inoff + 2], 2);
                                 attr_len = htole16(u16);
-
                                 if (attr_len > inlen || (outoff + attr_len) > alloc_len) {
                                         /* invalid, must be out of parse? */
                                         break;
@@ -1075,6 +1077,13 @@ ntlmssp_generate_blob(struct smb2_server *server, struct smb2_context *smb2, tim
                                         smb2_set_error(smb2, "can not decode challenge");
                                         return -1;
                                 }
+                                if (auth_data->domain == NULL && auth_data->target_name) {
+                                        smb2_set_domain(smb2, auth_data->target_name);
+                                        auth_data->domain = strdup(auth_data->target_name);
+                                        if (auth_data->domain == NULL) {
+                                                return -1;
+                                        }
+                                }
                                 if (encode_ntlm_auth(smb2, t, auth_data,
                                                      (char *)&auth_data->ntlm_buf[24]) < 0) {
                                         smb2_set_error(smb2, "can not encode auth data");