+ // validate the challenge
+ for (i = 0;i < MAX_CHALLENGES;i++)
+ if(challenge[i].time > 0)
+ if (!LHNETADDRESS_Compare(peeraddress, &challenge[i].address) && !strncmp(challenge[i].string, s, sizeof(challenge[0].string) - 1))
+ break;
+ // if the challenge is not recognized, drop the packet
+ if (i == MAX_CHALLENGES)
+ return false;
+
+ if(!HMAC_MDFOUR_16BYTES((unsigned char *) mdfourbuf, (unsigned char *) s, slen, (unsigned char *) password, strlen(password)))
+ return false;
+
+ if(memcmp(mdfourbuf, hash, 16))
+ return false;
+
+ // unmark challenge to prevent replay attacks
+ challenge[i].time = 0;
+
+ return true;
+}
+
+qboolean plaintext_matching(lhnetaddress_t *peeraddress, const char *password, const char *hash, const char *s, int slen)
+{
+ return !strcmp(password, hash);
+}
+
+/// returns a string describing the user level, or NULL for auth failure
+const char *RCon_Authenticate(lhnetaddress_t *peeraddress, const char *password, const char *s, const char *endpos, rcon_matchfunc_t comparator, const char *cs, int cslen)
+{
+ const char *text, *userpass_start, *userpass_end, *userpass_startpass;
+ static char buf[MAX_INPUTLINE];
+ qboolean hasquotes;
+ qboolean restricted = false;
+ qboolean have_usernames = false;
+
+ userpass_start = rcon_password.string;
+ while((userpass_end = strchr(userpass_start, ' ')))
+ {
+ have_usernames = true;
+ strlcpy(buf, userpass_start, ((size_t)(userpass_end-userpass_start) >= sizeof(buf)) ? (int)(sizeof(buf)) : (int)(userpass_end-userpass_start+1));
+ if(buf[0])
+ if(comparator(peeraddress, buf, password, cs, cslen))
+ goto allow;
+ userpass_start = userpass_end + 1;
+ }
+ if(userpass_start[0])
+ {
+ userpass_end = userpass_start + strlen(userpass_start);
+ if(comparator(peeraddress, userpass_start, password, cs, cslen))
+ goto allow;
+ }
+
+ restricted = true;
+ have_usernames = false;
+ userpass_start = rcon_restricted_password.string;
+ while((userpass_end = strchr(userpass_start, ' ')))
+ {
+ have_usernames = true;
+ strlcpy(buf, userpass_start, ((size_t)(userpass_end-userpass_start) >= sizeof(buf)) ? (int)(sizeof(buf)) : (int)(userpass_end-userpass_start+1));
+ if(buf[0])
+ if(comparator(peeraddress, buf, password, cs, cslen))
+ goto check;
+ userpass_start = userpass_end + 1;
+ }
+ if(userpass_start[0])
+ {
+ userpass_end = userpass_start + strlen(userpass_start);
+ if(comparator(peeraddress, userpass_start, password, cs, cslen))
+ goto check;
+ }
+
+ return NULL; // DENIED
+
+check: