[7.6] 0a76ab174 vmod_blob: Account for NUL to simplify alphabet initialization

[Walid Boudebouda]

commit 0a76ab174f10c210e2c0544c935b696d5e3ac244
Author: Nils Goroll <nils.goroll at uplex.de>
Date:   Wed Mar 19 16:31:23 2025 +0100

    vmod_blob: Account for NUL to simplify alphabet initialization
    
    Alphabets for base64 and hex are 64 and 16 bytes long, respectively, but
    initializing them with a string needs one additional byte for the final NUL.
    
    Fixes #4300

diff --git a/vmod/vmod_blob.h b/vmod/vmod_blob.h
index 90872b61a..f775dd6c9 100644
--- a/vmod/vmod_blob.h
+++ b/vmod/vmod_blob.h
@@ -140,7 +140,7 @@ len_f		hex_decode_l;
 encode_f	hex_encode;
 decode_f	hex_decode;
 
-extern const char	hex_alphabet[][16];
+extern const char	hex_alphabet[][17];
 extern const uint8_t	hex_nibble[];
 
 /* url.c */
diff --git a/vmod/vmod_blob_base64.c b/vmod/vmod_blob_base64.c
index 74a895754..971a05e91 100644
--- a/vmod/vmod_blob_base64.c
+++ b/vmod/vmod_blob_base64.c
@@ -37,7 +37,7 @@
 #include "vmod_blob.h"
 
 static const struct b64_alphabet {
-	const char b64[64];
+	const char b64[65];
 	const int8_t i64[256];
 	const int padding;
 } b64_alphabet[] = {
diff --git a/vmod/vmod_blob_hex.c b/vmod/vmod_blob_hex.c
index 539ab87a7..b11701940 100644
--- a/vmod/vmod_blob_hex.c
+++ b/vmod/vmod_blob_hex.c
@@ -38,7 +38,7 @@
 
 #include "vmod_blob.h"
 
-const char hex_alphabet[][16] = {
+const char hex_alphabet[][17] = {
 	"0123456789abcdef",
 	"0123456789ABCDEF"
 };