diff --git a/tests/scripts/all.sh b/tests/scripts/all.sh
index 602da2c..133d986 100755
--- a/tests/scripts/all.sh
+++ b/tests/scripts/all.sh
@@ -1,19 +1,29 @@
 #!/bin/sh
 
-# Run all available tests (mostly).
+# all.sh
 #
-# Warning: includes various build modes, so it will mess with the current
-# CMake configuration. After this script is run, the CMake cache is lost and
-# CMake is not initialised any more!
+# This file is part of mbed TLS (https://tls.mbed.org)
 #
-# Assumes gcc and clang (recent enough for using ASan with gcc and MemSan with
-# clang, or valgrind) are available, as well as cmake and a "good" find.
+# Copyright (c) 2014-2016, ARM Limited, All Rights Reserved
+#
+# Purpose
+#
+# To run all tests possible or available on the platform.
+#
+# Warning: the test is destructive. It includes various build modes and
+# configurations, and can and will arbitrarily change the current CMake
+# configuration. After this script has been run, the CMake cache will be lost
+# and CMake will no longer be initialised.
+#
+# The script assumes the presence of gcc and clang (recent enough for using
+# ASan with gcc and MemSan with clang, or valgrind) are available, as well as
+# cmake and a "good" find.
 
-# Abort on errors (and uninitiliased variables)
+# Abort on errors (and uninitialised variables)
 set -eu
 
 if [ -d library -a -d include -a -d tests ]; then :; else
-    echo "Must be run from mbed TLS root" >&2
+    err_msg "Must be run from mbed TLS root"
     exit 1
 fi
 
@@ -21,20 +31,34 @@
 CONFIG_BAK="$CONFIG_H.bak"
 
 MEMORY=0
+FORCE=0
+RELEASE=0
 
-while [ $# -gt 0 ]; do
-    case "$1" in
-        -m*)
-            MEMORY=${1#-m}
-            ;;
-        *)
-            echo "Unknown argument: '$1'" >&2
-            echo "Use the source, Luke!" >&2
-            exit 1
-            ;;
-    esac
-    shift
-done
+# Default commands, can be overriden by the environment
+: ${OPENSSL:="openssl"}
+: ${OPENSSL_LEGACY:="$OPENSSL"}
+: ${GNUTLS_CLI:="gnutls-cli"}
+: ${GNUTLS_SERV:="gnutls-serv"}
+: ${GNUTLS_LEGACY_CLI:="$GNUTLS_CLI"}
+: ${GNUTLS_LEGACY_SERV:="$GNUTLS_SERV"}
+: ${OUT_OF_SOURCE_DIR:=./mbedtls_out_of_source_build}
+
+usage()
+{
+    printf "Usage: $0\n"
+    printf "  -h|--help\t\tPrint this help.\n"
+    printf "  -m|--memory\t\tAdditional optional memory tests.\n"
+    printf "  -f|--force\t\tForce the tests to overwrite any modified files.\n"
+    printf "  -s|--seed\t\tInteger seed value to use for this test run.\n"
+    printf "  -r|--release-test\t\tRun this script in release mode. This fixes the seed value to 1.\n"
+    printf "     --out-of-source-dir=<path>\t\tDirectory used for CMake out-of-source build tests."
+    printf "     --openssl=<OpenSSL_path>\t\tPath to OpenSSL executable to use for most tests.\n"
+    printf "     --openssl-legacy=<OpenSSL_path>\t\tPath to OpenSSL executable to use for legacy tests e.g. SSLv3.\n"
+    printf "     --gnutls-cli=<GnuTLS_cli_path>\t\tPath to GnuTLS client executable to use for most tests.\n"
+    printf "     --gnutls-serv=<GnuTLS_serv_path>\t\tPath to GnuTLS server executable to use for most tests.\n"
+    printf "     --gnutls-legacy-cli=<GnuTLS_cli_path>\t\tPath to GnuTLS client executable to use for legacy tests.\n"
+    printf "     --gnutls-legacy-serv=<GnuTLS_serv_path>\t\tPath to GnuTLS server executable to use for legacy tests.\n"
+}
 
 # remove built files as well as the cmake cache/config
 cleanup()
@@ -62,6 +86,126 @@
     echo "******************************************************************"
 }
 
+err_msg()
+{
+    echo "$1" >&2
+}
+
+check_tools()
+{
+    for TOOL in "$@"; do
+        if ! `hash "$TOOL" >/dev/null 2>&1`; then
+            err_msg "$TOOL not found!"
+            exit 1
+        fi
+    done
+}
+
+while [ $# -gt 0 ]; do
+    case "$1" in
+        --memory|-m*)
+            MEMORY=${1#-m}
+            ;;
+        --force|-f)
+            FORCE=1
+            ;;
+        --seed|-s)
+            shift
+            SEED="$1"
+            ;;
+        --release-test|-r)
+            RELEASE=1
+            ;;
+        --out-of-source-dir)
+            shift
+            OUT_OF_SOURCE_DIR="$1"
+            ;;
+        --openssl)
+            shift
+            OPENSSL="$1"
+            ;;
+        --openssl-legacy)
+            shift
+            OPENSSL_LEGACY="$1"
+            ;;
+        --gnutls-cli)
+            shift
+            GNUTLS_CLI="$1"
+            ;;
+        --gnutls-serv)
+            shift
+            GNUTLS_SERV="$1"
+            ;;
+        --gnutls-legacy-cli)
+            shift
+            GNUTLS_LEGACY_CLI="$1"
+            ;;
+        --gnutls-legacy-serv)
+            shift
+            GNUTLS_LEGACY_SERV="$1"
+            ;;
+        --help|-h|*)
+            usage
+            exit 1
+            ;;
+    esac
+    shift
+done
+
+if [ $FORCE -eq 1 ]; then
+    git checkout-index -f -q $CONFIG_H
+    cleanup
+else
+
+    if [ -d "$OUT_OF_SOURCE_DIR" ]; then
+        echo "Warning - there is an existing directory at '$OUT_OF_SOURCE_DIR'" >&2
+        echo "You can either delete this directory manually, or force the test by rerunning"
+        echo "the script as: $0 --force --out-of-source-dir $OUT_OF_SOURCE_DIR"
+        exit 1
+    fi
+
+    if ! git diff-files --quiet include/polarssl/config.h; then
+        echo $?
+        err_msg "Warning - the configuration file 'include/polarssl/config.h' has been edited. "
+        echo "You can either delete or preserve your work, or force the test by rerunning the"
+        echo "script as: $0 --force"
+        exit 1
+    fi
+fi
+
+if [ $RELEASE -eq 1 ]; then
+    # Fix the seed value to 1 to ensure that the tests are deterministic.
+    SEED=1
+fi
+
+msg "info: $0 configuration"
+echo "MEMORY: $MEMORY"
+echo "FORCE: $FORCE"
+echo "SEED: ${SEED-"UNSET"}"
+echo "OPENSSL: $OPENSSL"
+echo "OPENSSL_LEGACY: $OPENSSL_LEGACY"
+echo "GNUTLS_CLI: $GNUTLS_CLI"
+echo "GNUTLS_SERV: $GNUTLS_SERV"
+echo "GNUTLS_LEGACY_CLI: $GNUTLS_LEGACY_CLI"
+echo "GNUTLS_LEGACY_SERV: $GNUTLS_LEGACY_SERV"
+
+# To avoid setting OpenSSL and GnuTLS for each call to compat.sh and ssl-opt.sh
+# we just export the variables they require
+export OPENSSL_CMD="$OPENSSL"
+export GNUTLS_CLI="$GNUTLS_CLI"
+export GNUTLS_SERV="$GNUTLS_SERV"
+
+# Avoid passing --seed flag in every call to ssl-opt.sh
+[ ! -z ${SEED+set} ] && export SEED
+
+# Make sure the tools we need are available.
+check_tools "$OPENSSL" "$OPENSSL_LEGACY" "$GNUTLS_CLI" "$GNUTLS_SERV" \
+    "$GNUTLS_LEGACY_CLI" "$GNUTLS_LEGACY_SERV" "doxygen" "dot" \
+    "arm-none-eabi-gcc" "armcc"
+
+#
+# Test Suites to be executed
+#
 # The test ordering tries to optimize for the following criteria:
 # 1. Catch possible problems early, by running first tests that run quickly
 #    and/or are more likely to fail than others (eg I use Clang most of the
@@ -81,27 +225,21 @@
 CC=gcc cmake -D CMAKE_BUILD_TYPE:String=Asan .
 make
 
-msg "test: main suites and selftest (ASan build)" # ~ 50s
+msg "test: main suites (inc. selftests) (ASan build)" # ~ 50s
 make test
 programs/test/selftest
 
 msg "test: ssl-opt.sh (ASan build)" # ~ 1 min
-cd tests
-./ssl-opt.sh
-cd ..
+tests/ssl-opt.sh
 
 msg "test/build: ref-configs (ASan build)" # ~ 6 min 20s
 tests/scripts/test-ref-configs.pl
 
-# Most frequent issues are likely to be caught at this point
-
 msg "build: with ASan (rebuild after ref-configs)" # ~ 1 min
 make
 
 msg "test: compat.sh (ASan build)" # ~ 6 min
-cd tests
-./compat.sh
-cd ..
+tests/compat.sh
 
 msg "build: Default + SSLv3 (ASan build)" # ~ 6 min
 cleanup
@@ -110,19 +248,16 @@
 CC=gcc cmake -D CMAKE_BUILD_TYPE:String=Asan .
 make
 
-msg "test: SSLv3 - main suites and selftest (ASan build)" # ~ 50s
+msg "test: SSLv3 - main suites (inc. selftests) (ASan build)" # ~ 50s
 make test
 programs/test/selftest
 
 msg "build: SSLv3 - compat.sh (ASan build)" # ~ 6 min
-cd tests
-./compat.sh -m 'ssl3 tls1 tls1_1 tls1_2'
-cd ..
+tests/compat.sh -m 'tls1 tls1_1 tls1_2'
+OPENSSL_CMD="$OPENSSL_LEGACY" tests/compat.sh -m 'ssl3'
 
 msg "build: SSLv3 - ssl-opt.sh (ASan build)" # ~ 6 min
-cd tests
-./ssl-opt.sh
-cd ..
+tests/ssl-opt.sh
 
 msg "build: cmake, full config, clang" # ~ 50s
 cleanup
@@ -138,16 +273,13 @@
 make test
 
 msg "test: ssl-opt.sh default (full config)" # ~ 1s
-cd tests
-./ssl-opt.sh -f Default
-cd ..
+tests/ssl-opt.sh -f Default
 
-msg "test: compat.sh DES & NULL (full config)" # ~ 2 min
-cd tests
-./compat.sh -e '^$' -f 'NULL\|3DES-EDE-CBC\|DES-CBC3'
-cd ..
+msg "test: compat.sh RC4, DES & NULL (full config)" # ~ 2 min
+OPENSSL_CMD="$OPENSSL_LEGACY" GNUTLS_CLI="$GNUTLS_LEGACY_CLI" GNUTLS_SERV="$GNUTLS_LEGACY_SERV" tests/compat.sh -e '^$' -f 'NULL\|3DES-EDE-CBC\|DES-CBC3'
 
-msg "test/build: curves.pl (gcc)" # ~ 5 min (?)
+
+msg "test/build: curves.pl (gcc)" # ~ 4 min
 cleanup
 cmake -D CMAKE_BUILD_TYPE:String=Debug .
 tests/scripts/curves.pl
@@ -185,6 +317,24 @@
 scripts/config.pl unset POLARSSL_PBKDF2_C # deprecated
 CC=gcc CFLAGS='-Werror -O0' make
 
+msg "build: full config except ssl_srv.c, make, gcc" # ~ 30s
+cleanup
+cp "$CONFIG_H" "$CONFIG_BAK"
+scripts/config.pl full
+scripts/config.pl unset POLARSSL_ERROR_STRERROR_BC # deprecated
+scripts/config.pl unset POLARSSL_PBKDF2_C # deprecated
+scripts/config.pl unset POLARSSL_SSL_SRV_C
+CC=gcc CFLAGS='-Werror -O0' make
+
+msg "build: full config except ssl_cli.c, make, gcc" # ~ 30s
+cleanup
+cp "$CONFIG_H" "$CONFIG_BAK"
+scripts/config.pl full
+scripts/config.pl unset POLARSSL_SSL_CLI_C
+scripts/config.pl unset POLARSSL_ERROR_STRERROR_BC # deprecated
+scripts/config.pl unset POLARSSL_PBKDF2_C # deprecated
+CC=gcc CFLAGS='-Werror -O0' make
+
 if uname -a | grep -F Linux >/dev/null; then
 msg "build/test: make shared" # ~ 40s
 cleanup
@@ -197,7 +347,6 @@
 CC=gcc CFLAGS='-Werror -m32' make
 fi # x86_64
 
-if which arm-none-eabi-gcc >/dev/null; then
 msg "build: arm-none-eabi-gcc, make" # ~ 10s
 cleanup
 cp "$CONFIG_H" "$CONFIG_BAK"
@@ -207,16 +356,15 @@
 scripts/config.pl unset POLARSSL_FS_IO
 scripts/config.pl unset POLARSSL_ERROR_STRERROR_BC # deprecated
 scripts/config.pl unset POLARSSL_PBKDF2_C # deprecated
+scripts/config.pl set POLARSSL_NO_PLATFORM_ENTROPY
 # following things are not in the default config
 scripts/config.pl unset POLARSSL_HAVEGE_C # depends on timing.c
 scripts/config.pl unset POLARSSL_THREADING_PTHREAD
 scripts/config.pl unset POLARSSL_THREADING_C
 scripts/config.pl unset POLARSSL_MEMORY_BACKTRACE # execinfo.h
 scripts/config.pl unset POLARSSL_MEMORY_BUFFER_ALLOC_C # calls exit
-CC=arm-none-eabi-gcc CFLAGS=-Werror make lib
-fi # arm-gcc
+CC=arm-none-eabi-gcc AR=arm-none-eabi-ar LD=arm-none-eabi-ld CFLAGS=-Werror make lib
 
-if which armcc >/dev/null; then
 msg "build: armcc, make"
 cleanup
 cp "$CONFIG_H" "$CONFIG_BAK"
@@ -227,6 +375,7 @@
 scripts/config.pl unset POLARSSL_HAVE_TIME
 scripts/config.pl unset POLARSSL_ERROR_STRERROR_BC # deprecated
 scripts/config.pl unset POLARSSL_PBKDF2_C # deprecated
+scripts/config.pl set POLARSSL_NO_PLATFORM_ENTROPY
 # following things are not in the default config
 scripts/config.pl unset POLARSSL_DEPRECATED_WARNING
 scripts/config.pl unset POLARSSL_HAVEGE_C # depends on timing.c
@@ -234,14 +383,7 @@
 scripts/config.pl unset POLARSSL_THREADING_C
 scripts/config.pl unset POLARSSL_MEMORY_BACKTRACE # execinfo.h
 scripts/config.pl unset POLARSSL_MEMORY_BUFFER_ALLOC_C # calls exit
-CC=armcc AR=armar WARNING_CFLAGS=
-make lib 2> armcc.stderr
-if [ -s armcc.stderr ]; then
-    cat armcc.stderr
-    exit 1;
-fi
-rm armcc.stderr
-fi # armcc
+CC=armcc AR=armar WARNING_CFLAGS= make lib
 
 if which i686-w64-mingw32-gcc >/dev/null; then
 msg "build: cross-mingw64, make" # ~ 30s
@@ -267,17 +409,13 @@
 make test
 
 msg "test: ssl-opt.sh (MSan)" # ~ 1 min
-cd tests
-./ssl-opt.sh
-cd ..
+tests/ssl-opt.sh
 
 # Optional part(s)
 
 if [ "$MEMORY" -gt 0 ]; then
     msg "test: compat.sh (MSan)" # ~ 6 min 20s
-    cd tests
-    ./compat.sh
-    cd ..
+    tests/compat.sh
 fi
 
 else # no MemSan
@@ -296,20 +434,29 @@
 
 if [ "$MEMORY" -gt 0 ]; then
     msg "test: ssl-opt.sh --memcheck (Release)"
-    cd tests
-    ./ssl-opt.sh --memcheck
-    cd ..
+    tests/ssl-opt.sh --memcheck
 fi
 
 if [ "$MEMORY" -gt 1 ]; then
     msg "test: compat.sh --memcheck (Release)"
-    cd tests
-    ./compat.sh --memcheck
-    cd ..
+    tests/compat.sh --memcheck
 fi
 
 fi # MemSan
 
+msg "build: cmake 'out-of-source' build"
+cleanup
+MBEDTLS_ROOT_DIR="$PWD"
+mkdir "$OUT_OF_SOURCE_DIR"
+cd "$OUT_OF_SOURCE_DIR"
+cmake "$MBEDTLS_ROOT_DIR"
+make
+
+msg "test: cmake 'out-of-source' build"
+make test
+cd "$MBEDTLS_ROOT_DIR"
+rm -rf "$OUT_OF_SOURCE_DIR"
+
 msg "Done, cleaning up"
 cleanup