vtls: fix MSVC 'cast truncates constant value' warning

Fixes:
```
curl\lib\vtls\cipher_suite.c(193,3): error C2220: the following warning is treated as an error
curl\lib\vtls\cipher_suite.c(193,3): warning C4310: cast truncates constant value
```

Closes #14341

diff --git a/lib/vtls/cipher_suite.c b/lib/vtls/cipher_suite.c
index 83ac5ddfaef641e0f771da64b3706a2b430d70a4..af9d55f09af1b9d521d2e40674ca7b95f625cb8f 100644 (file)
--- a/lib/vtls/cipher_suite.c
+++ b/lib/vtls/cipher_suite.c
@@ -163,24 +163,24 @@ enum {
   CS_TXT_LEN,
 };
 
-#define CS_ZIP_IDX(a, b, c, d, e, f, g, h)    \
-{                                             \
-  (uint8_t) ((a) << 2 | ((b) & 0x3F) >> 4),   \
-  (uint8_t) ((b) << 4 | ((c) & 0x3F) >> 2),   \
-  (uint8_t) ((c) << 6 | ((d) & 0x3F)),        \
-  (uint8_t) ((e) << 2 | ((f) & 0x3F) >> 4),   \
-  (uint8_t) ((f) << 4 | ((g) & 0x3F) >> 2),   \
-  (uint8_t) ((g) << 6 | ((h) & 0x3F))         \
+#define CS_ZIP_IDX(a, b, c, d, e, f, g, h)             \
+{                                                      \
+  (uint8_t) ((((a) << 2) & 0xFF) | ((b) & 0x3F) >> 4), \
+  (uint8_t) ((((b) << 4) & 0xFF) | ((c) & 0x3F) >> 2), \
+  (uint8_t) ((((c) << 6) & 0xFF) | ((d) & 0x3F)),      \
+  (uint8_t) ((((e) << 2) & 0xFF) | ((f) & 0x3F) >> 4), \
+  (uint8_t) ((((f) << 4) & 0xFF) | ((g) & 0x3F) >> 2), \
+  (uint8_t) ((((g) << 6) & 0xFF) | ((h) & 0x3F))       \
 }
-#define CS_ENTRY(id, a, b, c, d, e, f, g, h)  \
-{                                             \
-  id,                                         \
-  CS_ZIP_IDX(                                 \
-    CS_TXT_IDX_ ## a, CS_TXT_IDX_ ## b,       \
-    CS_TXT_IDX_ ## c, CS_TXT_IDX_ ## d,       \
-    CS_TXT_IDX_ ## e, CS_TXT_IDX_ ## f,       \
-    CS_TXT_IDX_ ## g, CS_TXT_IDX_ ## h        \
-  )                                           \
+#define CS_ENTRY(id, a, b, c, d, e, f, g, h)           \
+{                                                      \
+  id,                                                  \
+  CS_ZIP_IDX(                                          \
+    CS_TXT_IDX_ ## a, CS_TXT_IDX_ ## b,                \
+    CS_TXT_IDX_ ## c, CS_TXT_IDX_ ## d,                \
+    CS_TXT_IDX_ ## e, CS_TXT_IDX_ ## f,                \
+    CS_TXT_IDX_ ## g, CS_TXT_IDX_ ## h                 \
+  )                                                    \
 }
 
 struct cs_entry {