Only allow a maximum packet size of 255 bytes
This code was written with an assumption that the input/output buffer
sizes would not exceed 255 bytes. The assumption can be seen throughout
the code where it is using a "uint8_t" for size calculations when doing
offsets into the data buffers.
As this application was written for OpenBMC and the service list
provided by OpenBMC is very minimal, supporting a maximum request
buffer of 255 bytes is a fine assumption. Just need to enforce it.
Without this change, very unexpected things can happen with uint8_t
overflow issues when a packet size greater then 255 bytes is passed in
or created internally.
Tested:
- Verified a request with a packet size over 255 bytes is rejected
Change-Id: Icec15fe100d6514a3309fa89e9f79d565de05553
Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
diff --git a/slp_meta.hpp b/slp_meta.hpp
index 538bf9c..aab2f56 100644
--- a/slp_meta.hpp
+++ b/slp_meta.hpp
@@ -12,6 +12,9 @@
/** @brief SLP service lifetime */
constexpr auto LIFETIME = 5;
+/** @brief Largest input or output buffer allowed */
+constexpr size_t MAX_LEN = 255;
+
/** @brief Defines the constants for slp header.
* Size and the offsets.
*/