Adjust IsIdentValid test to comply with upcoming ircd-hybrid release (#272).

hybrid.cpp: adjust IsIdentValid test to comply with upcoming ircd-hybrid where
user names may only consist of [A-Za-z0-9._-] and may not begin with '.', '-',
or '_'.

As a side effect this fixes an issue where currently it is possible to introduce
bots whose user name starts with (non-alnum) characters considered invalid for
ircd-hybrid leading to a services shutdown due to a nick introduction/kill loop.

1 files changed, 18 insertions, 4 deletions

diff --git a/modules/protocol/hybrid.cpp b/modules/protocol/hybrid.cpp
index 640408052..3a1b6ce59 100644
--- a/modules/protocol/hybrid.cpp
+++ b/modules/protocol/hybrid.cpp
@@ -280,16 +280,30 @@ class HybridProto : public IRCDProto
 		if (ident.empty() || ident.length() > Config->GetBlock("networkinfo")->Get<unsigned>("userlen"))
 			return false;
 
-		Anope::string chars = "~}|{ `_^]\\[ .-$";
+		/*
+		 * If the user name begins with a tilde (~), make sure there is at least
+		 * one succeeding character.
+		 */
+		unsigned i = ident[0] == '~';
+		if (i >= ident.length())
+			return false;
+
+		/* User names may not start with a '-', '_', or '.'. */
+		const char &a = ident[i];
+		if (a == '-' || a == '_' || a == '.')
+			return false;
 
-		for (unsigned i = 0; i < ident.length(); ++i)
+		for (i = 0; i < ident.length(); ++i)
 		{
 			const char &c = ident[i];
 
-			if ((c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z') || (c >= '0' && c <= '9'))
+			/* A tilde can only be used as the first character of a user name. */
+			if (c == '~' && i == 0)
 				continue;
 
-			if (chars.find(c) != Anope::string::npos)
+			if ((c >= 'A' && c <= 'Z') ||
+				(c >= 'a' && c <= 'z') ||
+				(c >= '0' && c <= '9') || c == '-' || c == '_' || c == '.')
 				continue;
 
 			return false;