diff --git a/ChangeLog b/ChangeLog
index 20491ed..37373a2 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -128,6 +128,8 @@
    * Add `reproducible` option to `ssl_client2` and `ssl_server2` to enable
      test runs without variability. Contributed by Philippe Antoine (Catena
      cyber) in #2681.
+   * Adds fuzz targets, especially for continuous fuzzing with OSS-Fuzz.
+     Contributed by Philippe Antoine (Catena cyber).
 
 = mbed TLS 2.17.0 branch released 2019-03-19
 
diff --git a/include/mbedtls/x509_crt.h b/include/mbedtls/x509_crt.h
index cd3be09..6983d60 100644
--- a/include/mbedtls/x509_crt.h
+++ b/include/mbedtls/x509_crt.h
@@ -32,6 +32,7 @@
 
 #include "x509.h"
 #include "x509_crl.h"
+#include "bignum.h"
 
 /**
  * \addtogroup x509_module
diff --git a/programs/CMakeLists.txt b/programs/CMakeLists.txt
index 4cdae78..2af4d11 100644
--- a/programs/CMakeLists.txt
+++ b/programs/CMakeLists.txt
@@ -6,3 +6,6 @@
 add_subdirectory(test)
 add_subdirectory(x509)
 add_subdirectory(util)
+if (NOT WIN32)
+    add_subdirectory(fuzz)
+endif()
diff --git a/programs/Makefile b/programs/Makefile
index 4c05d91..857be78 100644
--- a/programs/Makefile
+++ b/programs/Makefile
@@ -90,9 +90,18 @@
 
 .SILENT:
 
-.PHONY: all clean list
+.PHONY: all clean list fuzz
 
 all: $(APPS)
+ifndef WINDOWS
+# APPS doesn't include the fuzzing programs, which aren't "normal"
+# sample or test programs, and don't build with MSVC which is
+# warning about fopen
+all: fuzz
+endif
+
+fuzz:
+	$(MAKE) -C fuzz
 
 $(DEP):
 	$(MAKE) -C ../library
@@ -305,6 +314,7 @@
 else
 	del /S /Q /F *.o *.exe
 endif
+	$(MAKE) -C fuzz clean
 
 list:
 	echo $(APPS)
diff --git a/programs/fuzz/.gitignore b/programs/fuzz/.gitignore
new file mode 100644
index 0000000..6fcc004
--- /dev/null
+++ b/programs/fuzz/.gitignore
@@ -0,0 +1,10 @@
+*.o
+fuzz_client
+fuzz_dtlsclient
+fuzz_dtlsserver
+fuzz_privkey
+fuzz_pubkey
+fuzz_server
+fuzz_x509crl
+fuzz_x509crt
+fuzz_x509csr
diff --git a/programs/fuzz/CMakeLists.txt b/programs/fuzz/CMakeLists.txt
new file mode 100644
index 0000000..17ec3f6
--- /dev/null
+++ b/programs/fuzz/CMakeLists.txt
@@ -0,0 +1,80 @@
+set(libs
+    mbedtls
+)
+
+if(USE_PKCS11_HELPER_LIBRARY)
+    set(libs ${libs} pkcs11-helper)
+endif(USE_PKCS11_HELPER_LIBRARY)
+
+if(ENABLE_ZLIB_SUPPORT)
+    set(libs ${libs} ${ZLIB_LIBRARIES})
+endif(ENABLE_ZLIB_SUPPORT)
+
+find_library(FUZZINGENGINE_LIB FuzzingEngine)
+
+if(NOT FUZZINGENGINE_LIB)
+    add_executable(fuzz_x509csr fuzz_x509csr.c onefile.c)
+    target_link_libraries(fuzz_x509csr ${libs})
+
+    add_executable(fuzz_x509crl fuzz_x509crl.c onefile.c)
+    target_link_libraries(fuzz_x509crl ${libs})
+
+    add_executable(fuzz_x509crt fuzz_x509crt.c onefile.c)
+    target_link_libraries(fuzz_x509crt ${libs})
+
+    add_executable(fuzz_privkey fuzz_privkey.c onefile.c)
+    target_link_libraries(fuzz_privkey ${libs})
+
+    add_executable(fuzz_pubkey fuzz_pubkey.c onefile.c)
+    target_link_libraries(fuzz_pubkey ${libs})
+
+    add_executable(fuzz_client fuzz_client.c common.c onefile.c)
+    target_link_libraries(fuzz_client ${libs})
+
+    add_executable(fuzz_server fuzz_server.c common.c onefile.c)
+    target_link_libraries(fuzz_server ${libs})
+
+    add_executable(fuzz_dtlsclient fuzz_dtlsclient.c common.c onefile.c)
+    target_link_libraries(fuzz_dtlsclient ${libs})
+
+    add_executable(fuzz_dtlsserver fuzz_dtlsserver.c common.c onefile.c)
+    target_link_libraries(fuzz_dtlsserver ${libs})
+else()
+    project(fuzz CXX)
+
+    add_executable(fuzz_x509csr fuzz_x509csr.c)
+    target_link_libraries(fuzz_x509csr ${libs} FuzzingEngine)
+    SET_TARGET_PROPERTIES(fuzz_x509csr PROPERTIES LINKER_LANGUAGE CXX)
+
+    add_executable(fuzz_x509crl fuzz_x509crl.c)
+    target_link_libraries(fuzz_x509crl ${libs} FuzzingEngine)
+    SET_TARGET_PROPERTIES(fuzz_x509crl PROPERTIES LINKER_LANGUAGE CXX)
+
+    add_executable(fuzz_x509crt fuzz_x509crt.c)
+    target_link_libraries(fuzz_x509crt ${libs} FuzzingEngine)
+    SET_TARGET_PROPERTIES(fuzz_x509crt PROPERTIES LINKER_LANGUAGE CXX)
+
+    add_executable(fuzz_privkey fuzz_privkey.c)
+    target_link_libraries(fuzz_privkey ${libs} FuzzingEngine)
+    SET_TARGET_PROPERTIES(fuzz_privkey PROPERTIES LINKER_LANGUAGE CXX)
+
+    add_executable(fuzz_pubkey fuzz_pubkey.c)
+    target_link_libraries(fuzz_pubkey ${libs} FuzzingEngine)
+    SET_TARGET_PROPERTIES(fuzz_pubkey PROPERTIES LINKER_LANGUAGE CXX)
+
+    add_executable(fuzz_client fuzz_client.c common.c)
+    target_link_libraries(fuzz_client ${libs} FuzzingEngine)
+    SET_TARGET_PROPERTIES(fuzz_client PROPERTIES LINKER_LANGUAGE CXX)
+
+    add_executable(fuzz_server fuzz_server.c common.c)
+    target_link_libraries(fuzz_server ${libs} FuzzingEngine)
+    SET_TARGET_PROPERTIES(fuzz_server PROPERTIES LINKER_LANGUAGE CXX)
+
+    add_executable(fuzz_dtlsclient fuzz_dtlsclient.c common.c)
+    target_link_libraries(fuzz_dtlsclient ${libs} FuzzingEngine)
+    SET_TARGET_PROPERTIES(fuzz_dtlsclient PROPERTIES LINKER_LANGUAGE CXX)
+
+    add_executable(fuzz_dtlsserver fuzz_dtlsserver.c common.c)
+    target_link_libraries(fuzz_dtlsserver ${libs} FuzzingEngine)
+    SET_TARGET_PROPERTIES(fuzz_dtlsserver PROPERTIES LINKER_LANGUAGE CXX)
+endif()
diff --git a/programs/fuzz/Makefile b/programs/fuzz/Makefile
new file mode 100644
index 0000000..f2195d1
--- /dev/null
+++ b/programs/fuzz/Makefile
@@ -0,0 +1,72 @@
+
+LOCAL_CFLAGS = -I../../include -D_FILE_OFFSET_BITS=64
+LOCAL_LDFLAGS = -L../../library			\
+		-lmbedtls$(SHARED_SUFFIX)	\
+		-lmbedx509$(SHARED_SUFFIX)	\
+		-lmbedcrypto$(SHARED_SUFFIX)
+
+LOCAL_LDFLAGS += -L../../crypto/library
+LOCAL_CFLAGS += -I../../crypto/include
+CRYPTO := ../../crypto/library/
+
+ifndef SHARED
+DEP=$(CRYPTO)libmbedcrypto.a ../../library/libmbedx509.a ../../library/libmbedtls.a
+else
+DEP=$(CRYPTO)libmbedcrypto.$(DLEXT) ../../library/libmbedx509.$(DLEXT) ../../library/libmbedtls.$(DLEXT)
+endif
+
+
+DLEXT ?= so
+EXEXT=
+SHARED_SUFFIX=
+# python2 for POSIX since FreeBSD has only python2 as default.
+PYTHON ?= python2
+
+# Zlib shared library extensions:
+ifdef ZLIB
+LOCAL_LDFLAGS += -lz
+endif
+
+ifdef FUZZINGENGINE
+LOCAL_LDFLAGS += -lFuzzingEngine
+endif
+
+# A test application is built for each suites/test_suite_*.data file.
+# Application name is same as .data file's base name and can be
+# constructed by stripping path 'suites/' and extension .data.
+APPS = $(basename $(wildcard fuzz_*.c))
+
+# Construct executable name by adding OS specific suffix $(EXEXT).
+BINARIES := $(addsuffix $(EXEXT),$(APPS))
+
+.SILENT:
+
+.PHONY: all check test clean
+
+all: $(BINARIES)
+
+$(DEP):
+	$(MAKE) -C ../../library
+
+C_FILES := $(addsuffix .c,$(APPS))
+
+%.o: %.c
+	$(CC) $(LOCAL_CFLAGS) $(CFLAGS) -c $<	-o $@
+
+
+ifdef FUZZINGENGINE
+$(BINARIES): %$(EXEXT): %.o common.o $(DEP)
+	echo " $(CC) common.o $< $(LOCAL_LDFLAGS) $(LDFLAGS) -o $@"
+	$(CXX) common.o $<	$(LOCAL_LDFLAGS) $(LDFLAGS) -o $@
+else
+$(BINARIES): %$(EXEXT): %.o common.o onefile.o $(DEP)
+	echo " $(CC) common.o onefile.o $< $(LOCAL_LDFLAGS) $(LDFLAGS) -o $@"
+	$(CC) common.o onefile.o $<	$(LOCAL_LDFLAGS) $(LDFLAGS) -o $@
+endif
+
+clean:
+ifndef WINDOWS
+	rm -rf $(BINARIES) *.o
+else
+	del /Q /F *.o *.exe
+endif
diff --git a/programs/fuzz/README.md b/programs/fuzz/README.md
new file mode 100644
index 0000000..8b24908
--- /dev/null
+++ b/programs/fuzz/README.md
@@ -0,0 +1,68 @@
+What is it?
+------
+
+This directory contains fuzz targets.
+Fuzz targets are simple codes using the library.
+They are used with a so-called fuzz driver, which will generate inputs, try to process them with the fuzz target, and alert in case of an unwanted behavior (such as a buffer overflow for instance).
+
+These targets were meant to be used with oss-fuzz but can be used in other contexts.
+
+This code was contributed by Philippe Antoine ( Catena cyber ).
+
+How to run?
+------
+
+To run the fuzz targets like oss-fuzz:
+```
+git clone https://github.com/google/oss-fuzz
+cd oss-fuzz
+python infra/helper.py build_image mbedtls
+python infra/helper.py build_fuzzers --sanitizer address mbedtls
+python infra/helper.py run_fuzzer mbedtls fuzz_client
+```
+You can use `undefined` sanitizer as well as `address` sanitizer.
+And you can run any of the fuzz targets like `fuzz_client`.
+
+To run the fuzz targets without oss-fuzz, you first need to install one libFuzzingEngine (libFuzzer for instance).
+Then you need to compile the code with the compiler flags of the wished sanitizer.
+```
+perl scripts/config.pl set MBEDTLS_PLATFORM_TIME_ALT
+mkdir build
+cd build
+cmake ..
+make
+```
+Finally, you can run the targets like `./test/fuzz/fuzz_client`.
+
+
+Corpus generation for network trafic targets
+------
+
+These targets use network trafic as inputs :
+* client : simulates a client against (fuzzed) server traffic
+* server : simulates a server against (fuzzed) client traffic
+* dtls_client
+* dtls_server
+
+They also use the last bytes as configuration options.
+
+To generate corpus for these targets, you can do the following, not fully automated steps :
+* Build mbedtls programs ssl_server2 and ssl_client2
+* Run them one against the other with `reproducible` option turned on while capturing trafic into test.pcap
+* Extract tcp payloads, for instance with tshark : `tshark -Tfields -e tcp.dstport -e tcp.payload -r test.pcap > test.txt`
+* Run a dummy python script to output either client or server corpus file like `python dummy.py test.txt > test.cor`
+* Finally, you can add the options by appending the last bytes to the file test.cor
+
+Here is an example of dummy.py for extracting payload from client to server (if we used `tcp.dstport` in tshark command)
+```
+import sys
+import binascii
+
+f = open(sys.argv[1])
+for l in f.readlines():
+    portAndPl=l.split()
+    if len(portAndPl) == 2:
+        # determine client or server based on port
+        if portAndPl[0] == "4433":
+            print(binascii.unhexlify(portAndPl[1].replace(":","")))
+```
diff --git a/programs/fuzz/common.c b/programs/fuzz/common.c
new file mode 100644
index 0000000..5e6c84c
--- /dev/null
+++ b/programs/fuzz/common.c
@@ -0,0 +1,91 @@
+#include "common.h"
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include "mbedtls/ctr_drbg.h"
+
+mbedtls_time_t dummy_constant_time( mbedtls_time_t* time )
+{
+    (void) time;
+    return 0x5af2a056;
+}
+
+void dummy_init()
+{
+#if defined(MBEDTLS_PLATFORM_TIME_ALT)
+    mbedtls_platform_set_time( dummy_constant_time );
+#else
+    fprintf(stderr, "Warning: fuzzing without constant time\n");
+#endif
+}
+
+int dummy_send( void *ctx, const unsigned char *buf, size_t len )
+{
+    //silence warning about unused parameter
+    (void) ctx;
+    (void) buf;
+
+    //pretends we wrote everything ok
+    if( len > INT_MAX ) {
+        return( -1 );
+    }
+    return( (int) len );
+}
+
+int fuzz_recv( void *ctx, unsigned char *buf, size_t len )
+{
+    //reads from the buffer from fuzzer
+    fuzzBufferOffset_t * biomemfuzz = (fuzzBufferOffset_t *) ctx;
+
+    if(biomemfuzz->Offset == biomemfuzz->Size) {
+        //EOF
+        return( 0 );
+    }
+    if( len > INT_MAX ) {
+        return( -1 );
+    }
+    if( len + biomemfuzz->Offset > biomemfuzz->Size ) {
+        //do not overflow
+        len = biomemfuzz->Size - biomemfuzz->Offset;
+    }
+    memcpy(buf, biomemfuzz->Data + biomemfuzz->Offset, len);
+    biomemfuzz->Offset += len;
+    return( (int) len );
+}
+
+int dummy_random( void *p_rng, unsigned char *output, size_t output_len )
+{
+    int ret;
+    size_t i;
+
+    //use mbedtls_ctr_drbg_random to find bugs in it
+    ret = mbedtls_ctr_drbg_random(p_rng, output, output_len);
+    for (i=0; i<output_len; i++) {
+        //replace result with pseudo random
+        output[i] = (unsigned char) rand();
+    }
+    return( ret );
+}
+
+int dummy_entropy( void *data, unsigned char *output, size_t len )
+{
+    size_t i;
+    (void) data;
+
+    //use mbedtls_entropy_func to find bugs in it
+    //test performance impact of entropy
+    //ret = mbedtls_entropy_func(data, output, len);
+    for (i=0; i<len; i++) {
+        //replace result with pseudo random
+        output[i] = (unsigned char) rand();
+    }
+    return( 0 );
+}
+
+int fuzz_recv_timeout( void *ctx, unsigned char *buf, size_t len,
+                      uint32_t timeout )
+{
+    (void) timeout;
+
+    return fuzz_recv(ctx, buf, len);
+}
diff --git a/programs/fuzz/common.h b/programs/fuzz/common.h
new file mode 100644
index 0000000..5586c06
--- /dev/null
+++ b/programs/fuzz/common.h
@@ -0,0 +1,19 @@
+#include "mbedtls/platform_time.h"
+#include <stdint.h>
+
+typedef struct fuzzBufferOffset
+{
+    const uint8_t *Data;
+    size_t Size;
+    size_t Offset;
+} fuzzBufferOffset_t;
+
+mbedtls_time_t dummy_constant_time( mbedtls_time_t* time );
+void dummy_init();
+
+int dummy_send( void *ctx, const unsigned char *buf, size_t len );
+int fuzz_recv( void *ctx, unsigned char *buf, size_t len );
+int dummy_random( void *p_rng, unsigned char *output, size_t output_len );
+int dummy_entropy( void *data, unsigned char *output, size_t len );
+int fuzz_recv_timeout( void *ctx, unsigned char *buf, size_t len,
+                      uint32_t timeout );
diff --git a/programs/fuzz/corpuses/client b/programs/fuzz/corpuses/client
new file mode 100644
index 0000000..48d0a67
--- /dev/null
+++ b/programs/fuzz/corpuses/client
Binary files differ
diff --git a/programs/fuzz/corpuses/dtlsclient b/programs/fuzz/corpuses/dtlsclient
new file mode 100644
index 0000000..87c3ca3
--- /dev/null
+++ b/programs/fuzz/corpuses/dtlsclient
Binary files differ
diff --git a/programs/fuzz/corpuses/dtlsserver b/programs/fuzz/corpuses/dtlsserver
new file mode 100644
index 0000000..7a7a117
--- /dev/null
+++ b/programs/fuzz/corpuses/dtlsserver
Binary files differ
diff --git a/programs/fuzz/corpuses/server b/programs/fuzz/corpuses/server
new file mode 100644
index 0000000..fbeb019
--- /dev/null
+++ b/programs/fuzz/corpuses/server
Binary files differ
diff --git a/programs/fuzz/fuzz_client.c b/programs/fuzz/fuzz_client.c
new file mode 100644
index 0000000..ca7a8ab
--- /dev/null
+++ b/programs/fuzz/fuzz_client.c
@@ -0,0 +1,173 @@
+#include "mbedtls/ssl.h"
+#include "mbedtls/entropy.h"
+#include "mbedtls/ctr_drbg.h"
+#include "mbedtls/certs.h"
+#include "common.h"
+#include <string.h>
+#include <stdlib.h>
+#include <stdint.h>
+
+
+#ifdef MBEDTLS_SSL_CLI_C
+static int initialized = 0;
+#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
+static mbedtls_x509_crt cacert;
+#endif
+const char *alpn_list[3];
+
+
+#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
+const unsigned char psk[] = {
+    0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+    0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f
+};
+const char psk_id[] = "Client_identity";
+#endif
+
+const char *pers = "fuzz_client";
+#endif //MBEDTLS_SSL_CLI_C
+
+
+int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
+#ifdef MBEDTLS_SSL_CLI_C
+    int ret;
+    size_t len;
+    mbedtls_ssl_context ssl;
+    mbedtls_ssl_config conf;
+    mbedtls_ctr_drbg_context ctr_drbg;
+    mbedtls_entropy_context entropy;
+    unsigned char buf[4096];
+    fuzzBufferOffset_t biomemfuzz;
+    uint16_t options;
+
+    if (initialized == 0) {
+#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
+        mbedtls_x509_crt_init( &cacert );
+        if (mbedtls_x509_crt_parse( &cacert, (const unsigned char *) mbedtls_test_cas_pem,
+                                   mbedtls_test_cas_pem_len ) != 0)
+            return 1;
+#endif
+
+        alpn_list[0] = "HTTP";
+        alpn_list[1] = "fuzzalpn";
+        alpn_list[2] = NULL;
+
+        dummy_init();
+
+        initialized = 1;
+    }
+
+    //we take 1 byte as options input
+    if (Size < 2) {
+        return 0;
+    }
+    options = (Data[Size - 2] << 8) | Data[Size - 1];
+    //Avoid warnings if compile options imply no options
+    (void) options;
+
+    mbedtls_ssl_init( &ssl );
+    mbedtls_ssl_config_init( &conf );
+    mbedtls_ctr_drbg_init( &ctr_drbg );
+    mbedtls_entropy_init( &entropy );
+
+    if( mbedtls_ctr_drbg_seed( &ctr_drbg, dummy_entropy, &entropy,
+                              (const unsigned char *) pers, strlen( pers ) ) != 0 )
+        goto exit;
+
+    if( mbedtls_ssl_config_defaults( &conf,
+                                    MBEDTLS_SSL_IS_CLIENT,
+                                    MBEDTLS_SSL_TRANSPORT_STREAM,
+                                    MBEDTLS_SSL_PRESET_DEFAULT ) != 0 )
+        goto exit;
+
+#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
+    if (options & 2) {
+        mbedtls_ssl_conf_psk( &conf, psk, sizeof( psk ),
+                             (const unsigned char *) psk_id, sizeof( psk_id ) - 1 );
+    }
+#endif
+
+#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
+    if (options & 4) {
+        mbedtls_ssl_conf_ca_chain( &conf, &cacert, NULL );
+        mbedtls_ssl_conf_authmode( &conf, MBEDTLS_SSL_VERIFY_REQUIRED );
+    } else
+#endif
+    {
+        mbedtls_ssl_conf_authmode( &conf, MBEDTLS_SSL_VERIFY_NONE );
+    }
+#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
+    mbedtls_ssl_conf_truncated_hmac( &conf, (options & 8) ? MBEDTLS_SSL_TRUNC_HMAC_ENABLED : MBEDTLS_SSL_TRUNC_HMAC_DISABLED);
+#endif
+#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
+    mbedtls_ssl_conf_extended_master_secret( &conf, (options & 0x10) ? MBEDTLS_SSL_EXTENDED_MS_DISABLED : MBEDTLS_SSL_EXTENDED_MS_ENABLED);
+#endif
+#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
+    mbedtls_ssl_conf_encrypt_then_mac( &conf, (options & 0x20) ? MBEDTLS_SSL_ETM_DISABLED : MBEDTLS_SSL_ETM_ENABLED);
+#endif
+#if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING)
+    mbedtls_ssl_conf_cbc_record_splitting( &conf, (options & 0x40) ? MBEDTLS_SSL_CBC_RECORD_SPLITTING_ENABLED : MBEDTLS_SSL_CBC_RECORD_SPLITTING_DISABLED );
+#endif
+#if defined(MBEDTLS_SSL_RENEGOTIATION)
+    mbedtls_ssl_conf_renegotiation( &conf, (options & 0x80) ? MBEDTLS_SSL_RENEGOTIATION_ENABLED : MBEDTLS_SSL_RENEGOTIATION_DISABLED );
+#endif
+#if defined(MBEDTLS_SSL_SESSION_TICKETS)
+    mbedtls_ssl_conf_session_tickets( &conf, (options & 0x100) ? MBEDTLS_SSL_SESSION_TICKETS_DISABLED : MBEDTLS_SSL_SESSION_TICKETS_ENABLED );
+#endif
+#if defined(MBEDTLS_SSL_ALPN)
+    if (options & 0x200) {
+        mbedtls_ssl_conf_alpn_protocols( &conf, alpn_list );
+    }
+#endif
+    //There may be other options to add :
+    // mbedtls_ssl_conf_cert_profile, mbedtls_ssl_conf_sig_hashes
+
+    srand(1);
+    mbedtls_ssl_conf_rng( &conf, dummy_random, &ctr_drbg );
+
+    if( mbedtls_ssl_setup( &ssl, &conf ) != 0 )
+        goto exit;
+
+#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
+    if ((options & 1) == 0) {
+        if( mbedtls_ssl_set_hostname( &ssl, "localhost" ) != 0 )
+            goto exit;
+    }
+#endif
+
+    biomemfuzz.Data = Data;
+    biomemfuzz.Size = Size-2;
+    biomemfuzz.Offset = 0;
+    mbedtls_ssl_set_bio( &ssl, &biomemfuzz, dummy_send, fuzz_recv, NULL );
+
+    ret = mbedtls_ssl_handshake( &ssl );
+    if( ret == 0 )
+    {
+        //keep reading data from server until the end
+        do
+        {
+            len = sizeof( buf ) - 1;
+            ret = mbedtls_ssl_read( &ssl, buf, len );
+
+            if( ret == MBEDTLS_ERR_SSL_WANT_READ )
+                continue;
+            else if( ret <= 0 )
+                //EOF or error
+                break;
+        }
+        while( 1 );
+    }
+
+exit:
+    mbedtls_entropy_free( &entropy );
+    mbedtls_ctr_drbg_free( &ctr_drbg );
+    mbedtls_ssl_config_free( &conf );
+    mbedtls_ssl_free( &ssl );
+
+#else
+    (void) Data;
+    (void) Size;
+#endif //MBEDTLS_SSL_CLI_C
+
+    return 0;
+}
diff --git a/programs/fuzz/fuzz_client.options b/programs/fuzz/fuzz_client.options
new file mode 100644
index 0000000..4d7340f
--- /dev/null
+++ b/programs/fuzz/fuzz_client.options
@@ -0,0 +1,2 @@
+[libfuzzer]
+max_len = 1048575
diff --git a/programs/fuzz/fuzz_dtlsclient.c b/programs/fuzz/fuzz_dtlsclient.c
new file mode 100644
index 0000000..8197a64
--- /dev/null
+++ b/programs/fuzz/fuzz_dtlsclient.c
@@ -0,0 +1,116 @@
+#include <string.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include "common.h"
+#include "mbedtls/ssl.h"
+#if defined(MBEDTLS_SSL_PROTO_DTLS)
+#include "mbedtls/entropy.h"
+#include "mbedtls/ctr_drbg.h"
+#include "mbedtls/certs.h"
+#include "mbedtls/timing.h"
+
+
+#ifdef MBEDTLS_SSL_CLI_C
+static int initialized = 0;
+#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
+static mbedtls_x509_crt cacert;
+#endif
+
+const char *pers = "fuzz_dtlsclient";
+#endif // MBEDTLS_SSL_CLI_C
+#endif // MBEDTLS_SSL_PROTO_DTLS
+
+
+
+int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
+#if defined(MBEDTLS_SSL_PROTO_DTLS) && defined(MBEDTLS_SSL_CLI_C)
+    int ret;
+    size_t len;
+    mbedtls_ssl_context ssl;
+    mbedtls_ssl_config conf;
+    mbedtls_ctr_drbg_context ctr_drbg;
+    mbedtls_entropy_context entropy;
+    mbedtls_timing_delay_context timer;
+    unsigned char buf[4096];
+    fuzzBufferOffset_t biomemfuzz;
+
+    if (initialized == 0) {
+#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
+        mbedtls_x509_crt_init( &cacert );
+        if (mbedtls_x509_crt_parse( &cacert, (const unsigned char *) mbedtls_test_cas_pem,
+                                   mbedtls_test_cas_pem_len ) != 0)
+            return 1;
+#endif
+        dummy_init();
+
+        initialized = 1;
+    }
+
+    mbedtls_ssl_init( &ssl );
+    mbedtls_ssl_config_init( &conf );
+    mbedtls_ctr_drbg_init( &ctr_drbg );
+    mbedtls_entropy_init( &entropy );
+
+    srand(1);
+    if( mbedtls_ctr_drbg_seed( &ctr_drbg, dummy_entropy, &entropy,
+                              (const unsigned char *) pers, strlen( pers ) ) != 0 )
+        goto exit;
+
+    if( mbedtls_ssl_config_defaults( &conf,
+                                    MBEDTLS_SSL_IS_CLIENT,
+                                    MBEDTLS_SSL_TRANSPORT_DATAGRAM,
+                                    MBEDTLS_SSL_PRESET_DEFAULT ) != 0 )
+        goto exit;
+
+#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
+    mbedtls_ssl_conf_ca_chain( &conf, &cacert, NULL );
+#endif
+    mbedtls_ssl_conf_authmode( &conf, MBEDTLS_SSL_VERIFY_NONE );
+    mbedtls_ssl_conf_rng( &conf, dummy_random, &ctr_drbg );
+
+    if( mbedtls_ssl_setup( &ssl, &conf ) != 0 )
+        goto exit;
+
+    mbedtls_ssl_set_timer_cb( &ssl, &timer, mbedtls_timing_set_delay,
+                             mbedtls_timing_get_delay );
+
+#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
+    if( mbedtls_ssl_set_hostname( &ssl, "localhost" ) != 0 )
+        goto exit;
+#endif
+
+    biomemfuzz.Data = Data;
+    biomemfuzz.Size = Size;
+    biomemfuzz.Offset = 0;
+    mbedtls_ssl_set_bio( &ssl, &biomemfuzz, dummy_send, fuzz_recv, fuzz_recv_timeout );
+
+    ret = mbedtls_ssl_handshake( &ssl );
+    if( ret == 0 )
+    {
+        //keep reading data from server until the end
+        do
+        {
+            len = sizeof( buf ) - 1;
+            ret = mbedtls_ssl_read( &ssl, buf, len );
+
+            if( ret == MBEDTLS_ERR_SSL_WANT_READ )
+                continue;
+            else if( ret <= 0 )
+                //EOF or error
+                break;
+        }
+        while( 1 );
+    }
+
+exit:
+    mbedtls_entropy_free( &entropy );
+    mbedtls_ctr_drbg_free( &ctr_drbg );
+    mbedtls_ssl_config_free( &conf );
+    mbedtls_ssl_free( &ssl );
+
+#else
+    (void) Data;
+    (void) Size;
+#endif
+    return 0;
+}
diff --git a/programs/fuzz/fuzz_dtlsclient.options b/programs/fuzz/fuzz_dtlsclient.options
new file mode 100644
index 0000000..4d7340f
--- /dev/null
+++ b/programs/fuzz/fuzz_dtlsclient.options
@@ -0,0 +1,2 @@
+[libfuzzer]
+max_len = 1048575
diff --git a/programs/fuzz/fuzz_dtlsserver.c b/programs/fuzz/fuzz_dtlsserver.c
new file mode 100644
index 0000000..9e9fe8e
--- /dev/null
+++ b/programs/fuzz/fuzz_dtlsserver.c
@@ -0,0 +1,141 @@
+#include <string.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include "common.h"
+#include "mbedtls/ssl.h"
+#if defined(MBEDTLS_SSL_PROTO_DTLS)
+#include "mbedtls/entropy.h"
+#include "mbedtls/ctr_drbg.h"
+#include "mbedtls/certs.h"
+#include "mbedtls/timing.h"
+#include "mbedtls/ssl_cookie.h"
+
+
+#ifdef MBEDTLS_SSL_SRV_C
+const char *pers = "fuzz_dtlsserver";
+const unsigned char client_ip[4] = {0x7F, 0, 0, 1};
+static int initialized = 0;
+#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
+static mbedtls_x509_crt srvcert;
+static mbedtls_pk_context pkey;
+#endif
+#endif // MBEDTLS_SSL_SRV_C
+#endif // MBEDTLS_SSL_PROTO_DTLS
+
+int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
+#if defined(MBEDTLS_SSL_PROTO_DTLS) && defined(MBEDTLS_SSL_SRV_C)
+    int ret;
+    size_t len;
+    mbedtls_ssl_context ssl;
+    mbedtls_ssl_config conf;
+    mbedtls_ctr_drbg_context ctr_drbg;
+    mbedtls_entropy_context entropy;
+    mbedtls_timing_delay_context timer;
+    mbedtls_ssl_cookie_ctx cookie_ctx;
+    unsigned char buf[4096];
+    fuzzBufferOffset_t biomemfuzz;
+
+    if (initialized == 0) {
+#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
+        mbedtls_x509_crt_init( &srvcert );
+        mbedtls_pk_init( &pkey );
+        if (mbedtls_x509_crt_parse( &srvcert, (const unsigned char *) mbedtls_test_srv_crt,
+                                   mbedtls_test_srv_crt_len ) != 0)
+            return 1;
+        if (mbedtls_x509_crt_parse( &srvcert, (const unsigned char *) mbedtls_test_cas_pem,
+                                   mbedtls_test_cas_pem_len ) != 0)
+            return 1;
+        if (mbedtls_pk_parse_key( &pkey, (const unsigned char *) mbedtls_test_srv_key,
+                                 mbedtls_test_srv_key_len, NULL, 0 ) != 0)
+            return 1;
+#endif
+        dummy_init();
+
+        initialized = 1;
+    }
+    mbedtls_ssl_init( &ssl );
+    mbedtls_ssl_config_init( &conf );
+    mbedtls_ctr_drbg_init( &ctr_drbg );
+    mbedtls_entropy_init( &entropy );
+    mbedtls_ssl_cookie_init( &cookie_ctx );
+
+    if( mbedtls_ctr_drbg_seed( &ctr_drbg, dummy_entropy, &entropy,
+                              (const unsigned char *) pers, strlen( pers ) ) != 0 )
+        goto exit;
+
+
+    if( mbedtls_ssl_config_defaults( &conf,
+                                    MBEDTLS_SSL_IS_SERVER,
+                                    MBEDTLS_SSL_TRANSPORT_DATAGRAM,
+                                    MBEDTLS_SSL_PRESET_DEFAULT ) != 0 )
+        goto exit;
+
+
+    srand(1);
+    mbedtls_ssl_conf_rng( &conf, dummy_random, &ctr_drbg );
+
+#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
+    mbedtls_ssl_conf_ca_chain( &conf, srvcert.next, NULL );
+    if( mbedtls_ssl_conf_own_cert( &conf, &srvcert, &pkey ) != 0 )
+        goto exit;
+#endif
+
+    if( mbedtls_ssl_cookie_setup( &cookie_ctx, dummy_random, &ctr_drbg ) != 0 )
+        goto exit;
+
+    mbedtls_ssl_conf_dtls_cookies( &conf, mbedtls_ssl_cookie_write, mbedtls_ssl_cookie_check, &cookie_ctx );
+
+    if( mbedtls_ssl_setup( &ssl, &conf ) != 0 )
+        goto exit;
+
+    mbedtls_ssl_set_timer_cb( &ssl, &timer, mbedtls_timing_set_delay,
+                             mbedtls_timing_get_delay );
+
+    biomemfuzz.Data = Data;
+    biomemfuzz.Size = Size;
+    biomemfuzz.Offset = 0;
+    mbedtls_ssl_set_bio( &ssl, &biomemfuzz, dummy_send, fuzz_recv, fuzz_recv_timeout );
+    if( mbedtls_ssl_set_client_transport_id( &ssl, client_ip, sizeof(client_ip) ) != 0 )
+        goto exit;
+
+    ret = mbedtls_ssl_handshake( &ssl );
+
+    if (ret == MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED) {
+        biomemfuzz.Offset = ssl.next_record_offset;
+        mbedtls_ssl_session_reset( &ssl );
+        mbedtls_ssl_set_bio( &ssl, &biomemfuzz, dummy_send, fuzz_recv, fuzz_recv_timeout );
+        if( mbedtls_ssl_set_client_transport_id( &ssl, client_ip, sizeof(client_ip) ) != 0 )
+            goto exit;
+
+        ret = mbedtls_ssl_handshake( &ssl );
+
+        if( ret == 0 )
+        {
+            //keep reading data from server until the end
+            do
+            {
+                len = sizeof( buf ) - 1;
+                ret = mbedtls_ssl_read( &ssl, buf, len );
+                if( ret == MBEDTLS_ERR_SSL_WANT_READ )
+                    continue;
+                else if( ret <= 0 )
+                    //EOF or error
+                    break;
+            }
+            while( 1 );
+        }
+    }
+
+exit:
+    mbedtls_ssl_cookie_free( &cookie_ctx );
+    mbedtls_entropy_free( &entropy );
+    mbedtls_ctr_drbg_free( &ctr_drbg );
+    mbedtls_ssl_config_free( &conf );
+    mbedtls_ssl_free( &ssl );
+
+#else
+    (void) Data;
+    (void) Size;
+#endif
+    return 0;
+}
diff --git a/programs/fuzz/fuzz_dtlsserver.options b/programs/fuzz/fuzz_dtlsserver.options
new file mode 100644
index 0000000..4d7340f
--- /dev/null
+++ b/programs/fuzz/fuzz_dtlsserver.options
@@ -0,0 +1,2 @@
+[libfuzzer]
+max_len = 1048575
diff --git a/programs/fuzz/fuzz_privkey.c b/programs/fuzz/fuzz_privkey.c
new file mode 100644
index 0000000..533a647
--- /dev/null
+++ b/programs/fuzz/fuzz_privkey.c
@@ -0,0 +1,64 @@
+#include <stdint.h>
+#include "mbedtls/pk.h"
+
+//4 Kb should be enough for every bug ;-)
+#define MAX_LEN 0x1000
+
+
+int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
+#ifdef MBEDTLS_PK_PARSE_C
+    int ret;
+    mbedtls_pk_context pk;
+
+    if (Size > MAX_LEN) {
+        //only work on small inputs
+        Size = MAX_LEN;
+    }
+
+    mbedtls_pk_init( &pk );
+    ret = mbedtls_pk_parse_key( &pk, Data, Size, NULL, 0 );
+    if (ret == 0) {
+#if defined(MBEDTLS_RSA_C)
+        if( mbedtls_pk_get_type( &pk ) == MBEDTLS_PK_RSA )
+        {
+            mbedtls_mpi N, P, Q, D, E, DP, DQ, QP;
+            mbedtls_rsa_context *rsa;
+
+            mbedtls_mpi_init( &N ); mbedtls_mpi_init( &P ); mbedtls_mpi_init( &Q );
+            mbedtls_mpi_init( &D ); mbedtls_mpi_init( &E ); mbedtls_mpi_init( &DP );
+            mbedtls_mpi_init( &DQ ); mbedtls_mpi_init( &QP );
+
+            rsa = mbedtls_pk_rsa( pk );
+            mbedtls_rsa_export( rsa, &N, &P, &Q, &D, &E );
+            mbedtls_rsa_export_crt( rsa, &DP, &DQ, &QP );
+
+            mbedtls_mpi_free( &N ); mbedtls_mpi_free( &P ); mbedtls_mpi_free( &Q );
+            mbedtls_mpi_free( &D ); mbedtls_mpi_free( &E ); mbedtls_mpi_free( &DP );
+            mbedtls_mpi_free( &DQ ); mbedtls_mpi_free( &QP );
+        }
+        else
+#endif
+#if defined(MBEDTLS_ECP_C)
+        if( mbedtls_pk_get_type( &pk ) == MBEDTLS_PK_ECKEY )
+        {
+            mbedtls_ecp_keypair *ecp;
+
+            ecp = mbedtls_pk_ec( pk );
+            if (ecp) {
+                ret = 0;
+            }
+        }
+        else
+#endif
+            {
+                ret = 0;
+            }
+    }
+    mbedtls_pk_free( &pk );
+#else
+    (void) Data;
+    (void) Size;
+#endif //MBEDTLS_PK_PARSE_C
+
+    return 0;
+}
diff --git a/programs/fuzz/fuzz_privkey.options b/programs/fuzz/fuzz_privkey.options
new file mode 100644
index 0000000..0824b19
--- /dev/null
+++ b/programs/fuzz/fuzz_privkey.options
@@ -0,0 +1,2 @@
+[libfuzzer]
+max_len = 65535
diff --git a/programs/fuzz/fuzz_pubkey.c b/programs/fuzz/fuzz_pubkey.c
new file mode 100644
index 0000000..df42f7d
--- /dev/null
+++ b/programs/fuzz/fuzz_pubkey.c
@@ -0,0 +1,57 @@
+#include <stdint.h>
+#include "mbedtls/pk.h"
+
+int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
+#ifdef MBEDTLS_PK_PARSE_C
+    int ret;
+    mbedtls_pk_context pk;
+
+    mbedtls_pk_init( &pk );
+    ret = mbedtls_pk_parse_public_key( &pk, Data, Size );
+    if (ret == 0) {
+#if defined(MBEDTLS_RSA_C)
+        if( mbedtls_pk_get_type( &pk ) == MBEDTLS_PK_RSA )
+        {
+            mbedtls_mpi N, P, Q, D, E, DP, DQ, QP;
+            mbedtls_rsa_context *rsa;
+
+            mbedtls_mpi_init( &N ); mbedtls_mpi_init( &P ); mbedtls_mpi_init( &Q );
+            mbedtls_mpi_init( &D ); mbedtls_mpi_init( &E ); mbedtls_mpi_init( &DP );
+            mbedtls_mpi_init( &DQ ); mbedtls_mpi_init( &QP );
+
+            rsa = mbedtls_pk_rsa( pk );
+            ret = mbedtls_rsa_export( rsa, &N, &P, &Q, &D, &E );
+            ret = mbedtls_rsa_export_crt( rsa, &DP, &DQ, &QP );
+
+            mbedtls_mpi_free( &N ); mbedtls_mpi_free( &P ); mbedtls_mpi_free( &Q );
+            mbedtls_mpi_free( &D ); mbedtls_mpi_free( &E ); mbedtls_mpi_free( &DP );
+            mbedtls_mpi_free( &DQ ); mbedtls_mpi_free( &QP );
+
+        }
+        else
+#endif
+#if defined(MBEDTLS_ECP_C)
+        if( mbedtls_pk_get_type( &pk ) == MBEDTLS_PK_ECKEY )
+        {
+            mbedtls_ecp_keypair *ecp;
+
+            ecp = mbedtls_pk_ec( pk );
+            //dummy use of value
+            if (ecp) {
+                ret = 0;
+            }
+        }
+        else
+#endif
+        {
+            ret = 0;
+        }
+    }
+    mbedtls_pk_free( &pk );
+#else
+    (void) Data;
+    (void) Size;
+#endif //MBEDTLS_PK_PARSE_C
+
+    return 0;
+}
diff --git a/programs/fuzz/fuzz_pubkey.options b/programs/fuzz/fuzz_pubkey.options
new file mode 100644
index 0000000..0824b19
--- /dev/null
+++ b/programs/fuzz/fuzz_pubkey.options
@@ -0,0 +1,2 @@
+[libfuzzer]
+max_len = 65535
diff --git a/programs/fuzz/fuzz_server.c b/programs/fuzz/fuzz_server.c
new file mode 100644
index 0000000..7cb5922
--- /dev/null
+++ b/programs/fuzz/fuzz_server.c
@@ -0,0 +1,185 @@
+#include "mbedtls/ssl.h"
+#include "mbedtls/entropy.h"
+#include "mbedtls/ctr_drbg.h"
+#include "mbedtls/certs.h"
+#include "mbedtls/ssl_ticket.h"
+#include "common.h"
+#include <string.h>
+#include <stdlib.h>
+#include <stdint.h>
+
+
+#ifdef MBEDTLS_SSL_SRV_C
+const char *pers = "fuzz_server";
+static int initialized = 0;
+#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
+static mbedtls_x509_crt srvcert;
+static mbedtls_pk_context pkey;
+#endif
+const char *alpn_list[3];
+
+#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
+const unsigned char psk[] = {
+    0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+    0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f
+};
+const char psk_id[] = "Client_identity";
+#endif
+#endif // MBEDTLS_SSL_SRV_C
+
+
+int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
+#ifdef MBEDTLS_SSL_SRV_C
+    int ret;
+    size_t len;
+    mbedtls_ssl_context ssl;
+    mbedtls_ssl_config conf;
+    mbedtls_ctr_drbg_context ctr_drbg;
+    mbedtls_entropy_context entropy;
+#if defined(MBEDTLS_SSL_SESSION_TICKETS)
+    mbedtls_ssl_ticket_context ticket_ctx;
+#endif
+    unsigned char buf[4096];
+    fuzzBufferOffset_t biomemfuzz;
+    uint8_t options;
+
+    //we take 1 byte as options input
+    if (Size < 1) {
+        return 0;
+    }
+    options = Data[Size - 1];
+
+    if (initialized == 0) {
+#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
+        mbedtls_x509_crt_init( &srvcert );
+        mbedtls_pk_init( &pkey );
+        if (mbedtls_x509_crt_parse( &srvcert, (const unsigned char *) mbedtls_test_srv_crt,
+                                   mbedtls_test_srv_crt_len ) != 0)
+            return 1;
+        if (mbedtls_x509_crt_parse( &srvcert, (const unsigned char *) mbedtls_test_cas_pem,
+                                   mbedtls_test_cas_pem_len ) != 0)
+            return 1;
+        if (mbedtls_pk_parse_key( &pkey, (const unsigned char *) mbedtls_test_srv_key,
+                                 mbedtls_test_srv_key_len, NULL, 0 ) != 0)
+            return 1;
+#endif
+
+        alpn_list[0] = "HTTP";
+        alpn_list[1] = "fuzzalpn";
+        alpn_list[2] = NULL;
+
+        dummy_init();
+
+        initialized = 1;
+    }
+    mbedtls_ssl_init( &ssl );
+    mbedtls_ssl_config_init( &conf );
+    mbedtls_ctr_drbg_init( &ctr_drbg );
+    mbedtls_entropy_init( &entropy );
+#if defined(MBEDTLS_SSL_SESSION_TICKETS)
+    mbedtls_ssl_ticket_init( &ticket_ctx );
+#endif
+
+    if( mbedtls_ctr_drbg_seed( &ctr_drbg, dummy_entropy, &entropy,
+                              (const unsigned char *) pers, strlen( pers ) ) != 0 )
+        goto exit;
+
+
+    if( mbedtls_ssl_config_defaults( &conf,
+                                    MBEDTLS_SSL_IS_SERVER,
+                                    MBEDTLS_SSL_TRANSPORT_STREAM,
+                                    MBEDTLS_SSL_PRESET_DEFAULT ) != 0 )
+        goto exit;
+
+    srand(1);
+    mbedtls_ssl_conf_rng( &conf, dummy_random, &ctr_drbg );
+
+#if defined(MBEDTLS_X509_CRT_PARSE_C) && defined(MBEDTLS_PEM_PARSE_C)
+    mbedtls_ssl_conf_ca_chain( &conf, srvcert.next, NULL );
+    if( mbedtls_ssl_conf_own_cert( &conf, &srvcert, &pkey ) != 0 )
+        goto exit;
+#endif
+
+    mbedtls_ssl_conf_cert_req_ca_list( &conf, (options & 0x1) ? MBEDTLS_SSL_CERT_REQ_CA_LIST_ENABLED : MBEDTLS_SSL_CERT_REQ_CA_LIST_DISABLED );
+#if defined(MBEDTLS_SSL_ALPN)
+    if (options & 0x2) {
+        mbedtls_ssl_conf_alpn_protocols( &conf, alpn_list );
+    }
+#endif
+#if defined(MBEDTLS_SSL_SESSION_TICKETS)
+    if( options & 0x4 )
+    {
+        if( mbedtls_ssl_ticket_setup( &ticket_ctx,
+                                     dummy_random, &ctr_drbg,
+                                     MBEDTLS_CIPHER_AES_256_GCM,
+                                     86400 ) != 0 )
+            goto exit;
+
+        mbedtls_ssl_conf_session_tickets_cb( &conf,
+                                            mbedtls_ssl_ticket_write,
+                                            mbedtls_ssl_ticket_parse,
+                                            &ticket_ctx );
+    }
+#endif
+#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
+    mbedtls_ssl_conf_truncated_hmac( &conf, (options & 0x8) ? MBEDTLS_SSL_TRUNC_HMAC_ENABLED : MBEDTLS_SSL_TRUNC_HMAC_DISABLED);
+#endif
+#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
+    mbedtls_ssl_conf_extended_master_secret( &conf, (options & 0x10) ? MBEDTLS_SSL_EXTENDED_MS_DISABLED : MBEDTLS_SSL_EXTENDED_MS_ENABLED);
+#endif
+#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
+    mbedtls_ssl_conf_encrypt_then_mac( &conf, (options & 0x20) ? MBEDTLS_SSL_ETM_ENABLED : MBEDTLS_SSL_ETM_DISABLED);
+#endif
+#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
+    if (options & 0x40) {
+        mbedtls_ssl_conf_psk( &conf, psk, sizeof( psk ),
+                             (const unsigned char *) psk_id, sizeof( psk_id ) - 1 );
+    }
+#endif
+#if defined(MBEDTLS_SSL_RENEGOTIATION)
+    mbedtls_ssl_conf_renegotiation( &conf, (options & 0x80) ? MBEDTLS_SSL_RENEGOTIATION_ENABLED : MBEDTLS_SSL_RENEGOTIATION_DISABLED );
+#endif
+
+    if( mbedtls_ssl_setup( &ssl, &conf ) != 0 )
+        goto exit;
+
+    biomemfuzz.Data = Data;
+    biomemfuzz.Size = Size-1;
+    biomemfuzz.Offset = 0;
+    mbedtls_ssl_set_bio( &ssl, &biomemfuzz, dummy_send, fuzz_recv, NULL );
+
+    mbedtls_ssl_session_reset( &ssl );
+    ret = mbedtls_ssl_handshake( &ssl );
+    if( ret == 0 )
+    {
+        //keep reading data from server until the end
+        do
+        {
+            len = sizeof( buf ) - 1;
+            ret = mbedtls_ssl_read( &ssl, buf, len );
+
+            if( ret == MBEDTLS_ERR_SSL_WANT_READ )
+                continue;
+            else if( ret <= 0 )
+                //EOF or error
+                break;
+        }
+        while( 1 );
+    }
+
+exit:
+#if defined(MBEDTLS_SSL_SESSION_TICKETS)
+    mbedtls_ssl_ticket_free( &ticket_ctx );
+#endif
+    mbedtls_entropy_free( &entropy );
+    mbedtls_ctr_drbg_free( &ctr_drbg );
+    mbedtls_ssl_config_free( &conf );
+    mbedtls_ssl_free( &ssl );
+
+#else
+    (void) Data;
+    (void) Size;
+#endif //MBEDTLS_SSL_SRV_C
+
+    return 0;
+}
diff --git a/programs/fuzz/fuzz_server.options b/programs/fuzz/fuzz_server.options
new file mode 100644
index 0000000..4d7340f
--- /dev/null
+++ b/programs/fuzz/fuzz_server.options
@@ -0,0 +1,2 @@
+[libfuzzer]
+max_len = 1048575
diff --git a/programs/fuzz/fuzz_x509crl.c b/programs/fuzz/fuzz_x509crl.c
new file mode 100644
index 0000000..02f521c
--- /dev/null
+++ b/programs/fuzz/fuzz_x509crl.c
@@ -0,0 +1,22 @@
+#include <stdint.h>
+#include "mbedtls/x509_crl.h"
+
+int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
+#ifdef MBEDTLS_X509_CRL_PARSE_C
+    int ret;
+    mbedtls_x509_crl crl;
+    unsigned char buf[4096];
+
+    mbedtls_x509_crl_init( &crl );
+    ret = mbedtls_x509_crl_parse( &crl, Data, Size );
+    if (ret == 0) {
+        ret = mbedtls_x509_crl_info( (char *) buf, sizeof( buf ) - 1, " ", &crl );
+    }
+    mbedtls_x509_crl_free( &crl );
+#else
+    (void) Data;
+    (void) Size;
+#endif
+
+    return 0;
+}
diff --git a/programs/fuzz/fuzz_x509crl.options b/programs/fuzz/fuzz_x509crl.options
new file mode 100644
index 0000000..0824b19
--- /dev/null
+++ b/programs/fuzz/fuzz_x509crl.options
@@ -0,0 +1,2 @@
+[libfuzzer]
+max_len = 65535
diff --git a/programs/fuzz/fuzz_x509crt.c b/programs/fuzz/fuzz_x509crt.c
new file mode 100644
index 0000000..8f593a1
--- /dev/null
+++ b/programs/fuzz/fuzz_x509crt.c
@@ -0,0 +1,22 @@
+#include <stdint.h>
+#include "mbedtls/x509_crt.h"
+
+int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
+#ifdef MBEDTLS_X509_CRT_PARSE_C
+    int ret;
+    mbedtls_x509_crt crt;
+    unsigned char buf[4096];
+
+    mbedtls_x509_crt_init( &crt );
+    ret = mbedtls_x509_crt_parse( &crt, Data, Size );
+    if (ret == 0) {
+        ret = mbedtls_x509_crt_info( (char *) buf, sizeof( buf ) - 1, " ", &crt );
+    }
+    mbedtls_x509_crt_free( &crt );
+#else
+    (void) Data;
+    (void) Size;
+#endif
+
+    return 0;
+}
diff --git a/programs/fuzz/fuzz_x509crt.options b/programs/fuzz/fuzz_x509crt.options
new file mode 100644
index 0000000..0824b19
--- /dev/null
+++ b/programs/fuzz/fuzz_x509crt.options
@@ -0,0 +1,2 @@
+[libfuzzer]
+max_len = 65535
diff --git a/programs/fuzz/fuzz_x509csr.c b/programs/fuzz/fuzz_x509csr.c
new file mode 100644
index 0000000..3cf28a6
--- /dev/null
+++ b/programs/fuzz/fuzz_x509csr.c
@@ -0,0 +1,22 @@
+#include <stdint.h>
+#include "mbedtls/x509_csr.h"
+
+int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
+#ifdef MBEDTLS_X509_CSR_PARSE_C
+    int ret;
+    mbedtls_x509_csr csr;
+    unsigned char buf[4096];
+
+    mbedtls_x509_csr_init( &csr );
+    ret = mbedtls_x509_csr_parse( &csr, Data, Size );
+    if (ret == 0) {
+        ret = mbedtls_x509_csr_info( (char *) buf, sizeof( buf ) - 1, " ", &csr );
+    }
+    mbedtls_x509_csr_free( &csr );
+#else
+    (void) Data;
+    (void) Size;
+#endif
+
+    return 0;
+}
diff --git a/programs/fuzz/fuzz_x509csr.options b/programs/fuzz/fuzz_x509csr.options
new file mode 100644
index 0000000..0824b19
--- /dev/null
+++ b/programs/fuzz/fuzz_x509csr.options
@@ -0,0 +1,2 @@
+[libfuzzer]
+max_len = 65535
diff --git a/programs/fuzz/onefile.c b/programs/fuzz/onefile.c
new file mode 100644
index 0000000..9e3986d
--- /dev/null
+++ b/programs/fuzz/onefile.c
@@ -0,0 +1,53 @@
+#include <stdint.h>
+#include <stdlib.h>
+#include <stdio.h>
+// Get platform-specific definition
+#include "mbedtls/config.h"
+
+int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size);
+
+int main(int argc, char** argv)
+{
+    FILE * fp;
+    uint8_t *Data;
+    size_t Size;
+
+    if (argc != 2) {
+        return 1;
+    }
+    //opens the file, get its size, and reads it into a buffer
+    fp = fopen(argv[1], "rb");
+    if (fp == NULL) {
+        return 2;
+    }
+    if (fseek(fp, 0L, SEEK_END) != 0) {
+        fclose(fp);
+        return 2;
+    }
+    Size = ftell(fp);
+    if (Size == (size_t) -1) {
+        fclose(fp);
+        return 2;
+    }
+    if (fseek(fp, 0L, SEEK_SET) != 0) {
+        fclose(fp);
+        return 2;
+    }
+    Data = malloc(Size);
+    if (Data == NULL) {
+        fclose(fp);
+        return 2;
+    }
+    if (fread(Data, Size, 1, fp) != 1) {
+        free(Data);
+        fclose(fp);
+        return 2;
+    }
+
+    //lauch fuzzer
+    LLVMFuzzerTestOneInput(Data, Size);
+    free(Data);
+    fclose(fp);
+    return 0;
+}
+
diff --git a/tests/compat.sh b/tests/compat.sh
index 0eae1ea..80c2d31 100755
--- a/tests/compat.sh
+++ b/tests/compat.sh
@@ -15,6 +15,10 @@
 
 set -u
 
+# Limit the size of each log to 10 GiB, in case of failures with this script
+# where it may output seemingly unlimited length error logs.
+ulimit -f 20971520
+
 # initialise counters
 TESTS=0
 FAILED=0
diff --git a/tests/scripts/all.sh b/tests/scripts/all.sh
index 42e00a1..1b799f7 100755
--- a/tests/scripts/all.sh
+++ b/tests/scripts/all.sh
@@ -24,7 +24,8 @@
 # configurations, and can and will arbitrarily change the current CMake
 # configuration. The following files must be committed into git:
 #    * include/mbedtls/config.h
-#    * Makefile, library/Makefile, programs/Makefile, tests/Makefile
+#    * Makefile, library/Makefile, programs/Makefile, tests/Makefile,
+#      programs/fuzz/Makefile
 # After running this script, the CMake cache will be lost and CMake
 # will no longer be initialised.
 #
@@ -75,9 +76,9 @@
 # * Run `make clean`.
 # * Restore `include/mbedtks/config.h` from a backup made before running
 #   the component.
-# * Check out `Makefile`, `library/Makefile`, `programs/Makefile` and
-#   `tests/Makefile` from git. This cleans up after an in-tree use of
-#   CMake.
+# * Check out `Makefile`, `library/Makefile`, `programs/Makefile`,
+#   `tests/Makefile` and `programs/fuzz/Makefile` from git.
+#   This cleans up after an in-tree use of CMake.
 #
 # Any command that is expected to fail must be protected so that the
 # script keeps running in --keep-going mode despite `set -e`. In keep-going
@@ -234,8 +235,8 @@
               -iname CMakeCache.txt \) -exec rm {} \+
     # Recover files overwritten by in-tree CMake builds
     rm -f include/Makefile include/mbedtls/Makefile programs/*/Makefile
-    git update-index --no-skip-worktree Makefile library/Makefile programs/Makefile tests/Makefile
-    git checkout -- Makefile library/Makefile programs/Makefile tests/Makefile
+    git update-index --no-skip-worktree Makefile library/Makefile programs/Makefile tests/Makefile programs/fuzz/Makefile
+    git checkout -- Makefile library/Makefile programs/Makefile tests/Makefile programs/fuzz/Makefile
     cd crypto
     rm -f include/Makefile include/mbedtls/Makefile programs/*/Makefile
     git update-index --no-skip-worktree Makefile library/Makefile programs/Makefile tests/Makefile
@@ -1052,7 +1053,7 @@
     # Build once with -O0, to compile out the i386 specific inline assembly
     msg "build: i386, make, gcc -O0 (ASan build)" # ~ 30s
     scripts/config.pl full
-    make CC=gcc CFLAGS='-O0 -Werror -Wall -Wextra -m32 -fsanitize=address' LDFLAGS='-m32'
+    make CC=gcc CFLAGS='-O0 -Werror -Wall -Wextra -m32 -fsanitize=address' LDFLAGS='-m32 -fsanitize=address'
 
     msg "test: i386, make, gcc -O0 (ASan build)"
     make test
@@ -1071,7 +1072,7 @@
     scripts/config.pl unset MBEDTLS_MEMORY_BACKTRACE
     scripts/config.pl unset MBEDTLS_MEMORY_BUFFER_ALLOC_C
     scripts/config.pl unset MBEDTLS_MEMORY_DEBUG
-    make CC=gcc CFLAGS='-O1 -Werror -Wall -Wextra -m32 -fsanitize=address' LDFLAGS='-m32'
+    make CC=gcc CFLAGS='-O1 -Werror -Wall -Wextra -m32 -fsanitize=address' LDFLAGS='-m32 -fsanitize=address'
 
     msg "test: i386, make, gcc -O1 (ASan build)"
     make test
diff --git a/tests/scripts/basic-build-test.sh b/tests/scripts/basic-build-test.sh
index 2c9deb9..4b71ff6 100755
--- a/tests/scripts/basic-build-test.sh
+++ b/tests/scripts/basic-build-test.sh
@@ -64,6 +64,7 @@
 
 # Step 1 - Make and instrumented build for code coverage
 export CFLAGS=' --coverage -g3 -O0 '
+export LDFLAGS=' --coverage'
 make clean
 cp "$CONFIG_H" "$CONFIG_BAK"
 scripts/config.pl full
diff --git a/tests/scripts/mbedtls_test.py b/tests/scripts/mbedtls_test.py
index ac2912d..6ac68a4 100755
--- a/tests/scripts/mbedtls_test.py
+++ b/tests/scripts/mbedtls_test.py
@@ -79,7 +79,7 @@
         split_colon_fn = lambda x: re.sub(r'\\' + split_char, split_char, x)
         if len(split_char) > 1:
             raise ValueError('Expected split character. Found string!')
-        out = map(split_colon_fn, re.split(r'(?<!\\)' + split_char, inp_str))
+        out = list(map(split_colon_fn, re.split(r'(?<!\\)' + split_char, inp_str)))
         out = [x for x in out if x]
         return out
 
@@ -99,11 +99,11 @@
 
             # Check dependencies
             dependencies = []
-            line = data_f.next().strip()
+            line = next(data_f).strip()
             match = re.search('depends_on:(.*)', line)
             if match:
                 dependencies = [int(x) for x in match.group(1).split(':')]
-                line = data_f.next().strip()
+                line = next(data_f).strip()
 
             # Read test vectors
             line = line.replace('\\n', '\n')
@@ -115,7 +115,7 @@
                 err_str_fmt = "Number of test arguments({}) should be even: {}"
                 raise TestDataParserError(err_str_fmt.format(args_count, line))
             grouped_args = [(args[i * 2], args[(i * 2) + 1])
-                            for i in range(len(args)/2)]
+                            for i in range(int(len(args)/2))]
             self.tests.append((name, function_name, dependencies,
                                grouped_args))
 
@@ -261,21 +261,21 @@
         data_bytes += bytearray([function_id, len(parameters)])
         for typ, param in parameters:
             if typ == 'int' or typ == 'exp':
-                i = int(param)
-                data_bytes += 'I' if typ == 'int' else 'E'
+                i = int(param, 0)
+                data_bytes += b'I' if typ == 'int' else b'E'
                 self.align_32bit(data_bytes)
                 data_bytes += self.int32_to_big_endian_bytes(i)
             elif typ == 'char*':
                 param = param.strip('"')
                 i = len(param) + 1  # + 1 for null termination
-                data_bytes += 'S'
+                data_bytes += b'S'
                 self.align_32bit(data_bytes)
                 data_bytes += self.int32_to_big_endian_bytes(i)
-                data_bytes += bytearray(list(param))
-                data_bytes += '\0'   # Null terminate
+                data_bytes += bytearray(param, encoding='ascii')
+                data_bytes += b'\0'   # Null terminate
             elif typ == 'hex':
                 binary_data = self.hex_str_bytes(param)
-                data_bytes += 'H'
+                data_bytes += b'H'
                 self.align_32bit(data_bytes)
                 i = len(binary_data)
                 data_bytes += self.int32_to_big_endian_bytes(i)
@@ -310,7 +310,7 @@
 
         param_bytes, length = self.test_vector_to_bytes(function_id,
                                                         dependencies, args)
-        self.send_kv(length, param_bytes)
+        self.send_kv(''.join('{:02x}'.format(x) for x in length), ''.join('{:02x}'.format(x) for x in param_bytes))
 
     @staticmethod
     def get_result(value):
diff --git a/tests/ssl-opt.sh b/tests/ssl-opt.sh
index f54295b..ed97f23 100755
--- a/tests/ssl-opt.sh
+++ b/tests/ssl-opt.sh
@@ -21,6 +21,10 @@
 
 set -u
 
+# Limit the size of each log to 10 GiB, in case of failures with this script
+# where it may output seemingly unlimited length error logs.
+ulimit -f 20971520
+
 if cd $( dirname $0 ); then :; else
     echo "cd $( dirname $0 ) failed" >&2
     exit 1
diff --git a/tests/suites/target_test.function b/tests/suites/target_test.function
index e4c3e30..d430d9d 100644
--- a/tests/suites/target_test.function
+++ b/tests/suites/target_test.function
@@ -59,10 +59,29 @@
     return( DEPENDENCY_SUPPORTED );
 }
 
+/**
+ * \brief       Receives hex string on serial interface, and converts to a byte.
+ *
+ * \param none
+ *
+ * \return      unsigned int8
+ */
+uint8_t receive_byte()
+{
+    uint8_t byte;
+    uint8_t c[3];
+    char *endptr;
+    c[0] = greentea_getc();
+    c[1] = greentea_getc();
+    c[2] = '\0';
+
+    assert( unhexify( &byte, c ) != 2 );
+    return( byte );
+}
 
 /**
  * \brief       Receives unsigned integer on serial interface.
- *              Integers are encoded in network order.
+ *              Integers are encoded in network order, and sent as hex ascii string.
  *
  * \param none
  *
@@ -71,10 +90,17 @@
 uint32_t receive_uint32()
 {
     uint32_t value;
-    value =  (uint8_t)greentea_getc() << 24;
-    value |= (uint8_t)greentea_getc() << 16;
-    value |= (uint8_t)greentea_getc() << 8;
-    value |= (uint8_t)greentea_getc();
+    const uint8_t c[9] = { greentea_getc(),
+                           greentea_getc(),
+                           greentea_getc(),
+                           greentea_getc(),
+                           greentea_getc(),
+                           greentea_getc(),
+                           greentea_getc(),
+                           greentea_getc(),
+                           '\0'
+                         };
+    assert( unhexify( &value, c ) != 8 );
     return( (uint32_t)value );
 }
 
@@ -132,7 +158,7 @@
     greentea_getc(); // read ';' received after key i.e. *data_len
 
     for( i = 0; i < *data_len; i++ )
-        data[i] = greentea_getc();
+        data[i] = receive_byte();
 
     /* Read closing braces */
     for( i = 0; i < 2; i++ )