Change the type of in_hsfraglen to unsigned
In the `mbedtls_ssl_context` structure, change the type of `in_hsfraglen`
from `size_t` to `unsigned`. This is in preparation for merging
`in_hsfraglen` into `badmac_seen_or_in_hsfraglen`, which has the type
`unsigned` and cannot change since we do not want to change the ABI.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/library/ssl_msg.c b/library/ssl_msg.c
index 1ad8f5a..5940aba 100644
--- a/library/ssl_msg.c
+++ b/library/ssl_msg.c
@@ -25,6 +25,7 @@
#include "constant_time_internal.h"
#include "mbedtls/constant_time.h"
+#include <limits.h>
#include <string.h>
#if defined(MBEDTLS_USE_PSA_CRYPTO)
@@ -3300,15 +3301,22 @@
int ret;
const size_t hs_remain = ssl->in_hslen - ssl->in_hsfraglen;
MBEDTLS_SSL_DEBUG_MSG(3,
- ("handshake fragment: %" MBEDTLS_PRINTF_SIZET " .. %"
+ ("handshake fragment: %u .. %"
MBEDTLS_PRINTF_SIZET " of %"
MBEDTLS_PRINTF_SIZET " msglen %" MBEDTLS_PRINTF_SIZET,
ssl->in_hsfraglen,
- ssl->in_hsfraglen +
+ (size_t) ssl->in_hsfraglen +
(hs_remain <= ssl->in_msglen ? hs_remain : ssl->in_msglen),
ssl->in_hslen, ssl->in_msglen));
if (ssl->in_msglen < hs_remain) {
- ssl->in_hsfraglen += ssl->in_msglen;
+ /* ssl->in_msglen is a 25-bit value since it is the sum of the
+ * header length plus the payload length, the header length is 4
+ * and the payload length was received on the wire encoded as
+ * 3 octets. We don't support 16-bit platforms; more specifically,
+ * we assume that both unsigned and size_t are at least 32 bits.
+ * Therefore there is no possible integer overflow here.
+ */
+ ssl->in_hsfraglen += (unsigned) ssl->in_msglen;
ssl->in_hdr = ssl->in_msg + ssl->in_msglen;
ssl->in_msglen = 0;
mbedtls_ssl_update_in_pointers(ssl);
@@ -4697,7 +4705,7 @@
if (ssl->in_hsfraglen != 0) {
/* Not all handshake fragments have arrived, do not consume. */
MBEDTLS_SSL_DEBUG_MSG(3,
- ("waiting for more fragments (%" MBEDTLS_PRINTF_SIZET " of %"
+ ("waiting for more fragments (%u of %"
MBEDTLS_PRINTF_SIZET ", %" MBEDTLS_PRINTF_SIZET " left)",
ssl->in_hsfraglen, ssl->in_hslen,
ssl->in_hslen - ssl->in_hsfraglen));