From: Alan T. DeKok <aland@freeradius.org>
Date: Wed, 27 Sep 2023 18:58:28 +0000 (-0400)
Subject: don't allow registrations of one-letter overlaps with %Y etc.
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=00f3ab776819e28caa12b7c7ef57862bf1dccd76;p=thirdparty%2Ffreeradius-server.git

don't allow registrations of one-letter overlaps with %Y etc.
---

diff --git a/src/lib/unlang/xlat_func.c b/src/lib/unlang/xlat_func.c
index 182f6304995..9c4960a8a76 100644
--- a/src/lib/unlang/xlat_func.c
+++ b/src/lib/unlang/xlat_func.c
@@ -206,6 +206,7 @@ xlat_t *xlat_func_register_module(TALLOC_CTX *ctx, module_inst_ctx_t const *mctx
 	fr_assert(xlat_root);
 
 	if (!*name) {
+	invalid_name:
 		ERROR("%s: Invalid xlat name", __FUNCTION__);
 		return NULL;
 	}
@@ -220,6 +221,8 @@ xlat_t *xlat_func_register_module(TALLOC_CTX *ctx, module_inst_ctx_t const *mctx
 	}
 
 	len = strlen(name);
+	if ((len == 1) && (strchr("InscCdDeGHlmMStTY", *name) != NULL)) goto invalid_name;
+
 	in = FR_SBUFF_IN(name, len);
 	fr_sbuff_adv_past_allowed(&in, SIZE_MAX, xlat_func_chars, NULL);
 	used = fr_sbuff_used(&in);