From ed3b10a6af2f00ffa10f3835b7adda5a7ee170ac Mon Sep 17 00:00:00 2001
From: Nicole Kleinhoff <ilbelkyr@shalture.org>
Date: Tue, 12 Jan 2021 08:16:13 +0000
Subject: [PATCH] Add IRCCloud cloaking type

This cloaking type is entirely specific to the IRCCloud service. It
operates in a fashion similar to to the ident cloaking type, however the
assigned gateway cloak will not include the 'u' or 's', only the
letters "id" and the subscriber ID itself.

Both uid1234 and sid1234 will thus result in a gateway/.../id1234 cloak.
---
 facilities.c | 45 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 45 insertions(+)

diff --git a/facilities.c b/facilities.c
index dda9d1c..1d9e680 100644
--- a/facilities.c
+++ b/facilities.c
@@ -55,6 +55,7 @@ typedef enum
     facility_cloak_hex_ident,
     facility_cloak_ident,
     facility_cloak_account,
+    facility_cloak_irccloud,
 } facility_cloak_type;
 
 static struct {
@@ -67,6 +68,7 @@ static struct {
     { "hexip",     facility_cloak_hex_ident },
     { "ident",     facility_cloak_ident     },
     { "account",   facility_cloak_account   },
+    { "irccloud",  facility_cloak_irccloud  },
     { NULL, 0 }
 };
 
@@ -532,6 +534,47 @@ void facility_newuser(hook_user_nick_t *data)
                 facility_set_cloak(u, new_vhost, cloak_override);
                 break;
             }
+        case facility_cloak_irccloud:
+            {
+                char *idstart = strstr(new_vhost, "session");
+                if (idstart == NULL)
+                {
+                    syn_debug(2, "IRCCloud cloaking used for %s, but I couldn't find a session marker in %s", u->nick, new_vhost);
+                    break;
+                }
+
+                const char *ident = u->user;
+                if (*ident == '~')
+                    ++ident;
+
+                if (strncmp(ident, "uid", 3) && strncmp(ident, "sid", 3))
+                    goto irccloud_error;
+
+                // Skip u/s
+                ident++;
+
+                // make sure we actually have an ID after the "id"
+                if (!ident[2])
+                    goto irccloud_error;
+
+                // skip "id", then check it's digits only
+                for (const char *c = ident + 2; *c; c++)
+                {
+                    if (!isdigit(*c))
+                        goto irccloud_error;
+                }
+
+                strncpy(idstart, ident, new_vhost + HOSTLEN - idstart);
+                facility_set_cloak(u, new_vhost, cloak_override);
+                break;
+
+irccloud_error:
+                syn_report("Killing user %s; facility %s requires irccloud ident but ident doesn't match",
+                        u->nick, cloaking_facility->hostpart);
+                syn_kill2(u, "No user ID supplied", "Your gateway requires a user ID to be supplied, which could not be found.");
+                data->u = NULL;
+                return;
+            }
         case facility_cloak_random:
             {
                 char *randstart = strstr(new_vhost, "session");
@@ -615,6 +658,8 @@ static void syn_facility_help(sourceinfo_t *si, const char *subcmd)
         command_success_nodata(si, "   way, it falls back to the random method.");
         command_success_nodata(si, " - ident. The user's ident is placed in their host directly");
         command_success_nodata(si, "   (with special characters removed appropriately).");
+        command_success_nodata(si, " - irccloud. The user's IRCCloud ID is placed in their host");
+        command_success_nodata(si, "   after removing the initial u/s.");
         command_success_nodata(si, " - account. This is meant to be used with a sasl_usercloak");
         command_success_nodata(si, "   auth {} block and applies the host generated by the ircd");
         command_success_nodata(si, "   as gateway cloak, overriding unaffiliated cloaks.");