This repository contains the RISC OS AMU port of Mbed TLS 4.1.0. It is
configured for client-side TLS 1.2 and TLS 1.3, SNI, certificate verification,
and the PSA crypto interface used by AcornSSL. The makefile selects the
CLibrary rules under DDE32 and the LibExport rules under the current RISC OS
build system.
The RISC OS configuration disables the optional Unix/Windows timing module;
DTLS is not enabled, so AcornSSL's TLS 1.2/1.3 operation does not require it.
Elapsed time is supplied by OS_ReadMonotonicTime. Entropy is supplied by the
RISC OS CryptRandom_Block SWI, so the CryptRandom module must be present at
runtime. The socket wrapper uses DDE's TCPIPLibs headers and libraries.
The RISC OS package metadata is version 4.10, matching the Mbed TLS 4.1.0 source release. This directory is the working source tree for DDE/AMU builds:
riscos-amu
riscos-amu export
The source is adapted for the Norcroft/RISC OS build environment, including its 32-bit fixed-width integer and TCP/IP interfaces.
Certificates/ca-certificates.crt is the PEM trust store for clients built with this
port. It is the Mozilla CA root bundle published by the curl project, fetched
on 24 July 2026; its embedded Mozilla data date is 16 July 2026. The file
contains 119 root certificates and has SHA-256:
3ff344e30b9b1ed2971044eabb438a08f2e2245ddb5f8ab1a3ad8b63ab4eaf91
Applications must load this file with their Mbed TLS X.509 trust-store setup. Refresh it periodically from https://curl.se/ca/cacert.pem; it is runtime data and does not require rebuilding the Mbed TLS libraries.
The upstream Mbed TLS code is available under the Apache-2.0 or GPL-2.0-or- later terms. RISC OS port changes retain the upstream licensing notices.