From: Alexander Barton <alex@barton.de>
Date: Fri, 1 Jun 2012 22:24:53 +0000 (+0200)
Subject: IDENT reply: only allow alphanumeric characters in user name
X-Git-Tag: rel-19.2-rc1~7
X-Git-Url: https://arthur.barton.de/cgi-bin/gitweb.cgi?p=ngircd-alex.git;a=commitdiff_plain;h=695df6532ec717e5571e1ddc2c88a8c968603c5a

IDENT reply: only allow alphanumeric characters in user name

Only alphanumeric characters are allowed in the user name, so ignore
all IDENT replies that would violate this rule and use the one supplied
by the USER command.
---

diff --git a/src/ngircd/conn.c b/src/ngircd/conn.c
index b6e62809..4d778719 100644
--- a/src/ngircd/conn.c
+++ b/src/ngircd/conn.c
@@ -2174,6 +2174,7 @@ cb_Read_Resolver_Result( int r_fd, UNUSED short events )
 	char *identptr;
 #ifdef IDENTAUTH
 	char readbuf[HOST_LEN + 2 + CLIENT_USER_LEN];
+	char *ptr;
 #else
 	char readbuf[HOST_LEN + 1];
 #endif
@@ -2226,11 +2227,30 @@ cb_Read_Resolver_Result( int r_fd, UNUSED short events )
 #ifdef IDENTAUTH
 		++identptr;
 		if (*identptr) {
-			Log(LOG_INFO, "IDENT lookup for connection %d: \"%s\".", i, identptr);
-			Client_SetUser(c, identptr, true);
-			if (Conf_NoticeAuth)
+			ptr = identptr;
+			while (*ptr) {
+				if ((*ptr < '0' || *ptr > '9') &&
+				    (*ptr < 'A' || *ptr > 'Z') &&
+				    (*ptr < 'a' || *ptr > 'z'))
+					break;
+				ptr++;
+			}
+			if (*ptr) {
+				/* Erroneous IDENT reply */
+				Log(LOG_NOTICE,
+				    "Got invalid IDENT reply for connection %d! Ignored.",
+				    i);
+			} else {
+				Log(LOG_INFO,
+				    "IDENT lookup for connection %d: \"%s\".",
+				    i, identptr);
+				Client_SetUser(c, identptr, true);
+			}
+			if (Conf_NoticeAuth) {
 				(void)Conn_WriteStr(i,
-					"NOTICE AUTH :*** Got ident response");
+					"NOTICE AUTH :*** Got %sident response",
+					*ptr == NULL ? "" : "invalid ");
+			}
 		} else {
 			Log(LOG_INFO, "IDENT lookup for connection %d: no result.", i);
 			if (Conf_NoticeAuth && Conf_Ident)