add mbedtls crypto support

Summary:
This patch adds support for mbedTLS as a crypto backend for libssh.
mbedTLS is an SSL/TLS library that has been designed to mainly be used
in embedded systems.  It is loosely coupled and has a low memory
footprint.  mbedTLS also provides a cryptography library (libmbedcrypto)
that can be used without the TLS modules.
The patch is unfortunately quite big, since several new files had to
be added.
DSA is disabled at compile time, since mbedTLS doesn't support DSA
Patch review and feedback would be appreciated, and if any issues or
suggestions appear, I'm willing to work on them.

Signed-off-by: Juraj Vijtiuk <juraj.vijtiuk@sartura.hr>

Test Plan:
* The patch has been tested with a Debug and MinSizeRel build, with
libssh unit tests, client tests and the pkd tests.
* All the tests have been run with valgrind's memcheck, drd and helgrind
tools.
* The examples/samplessh client works when built with the patch.

Reviewers: asn, aris

Subscribers: simonsj

Differential Revision: https://bugs.libssh.org/D1

5 files changed, 121 insertions, 0 deletions

diff --git a/tests/pkd/pkd_daemon.c b/tests/pkd/pkd_daemon.c
index 9860ca56..a128c8e9 100644
--- a/tests/pkd/pkd_daemon.c
+++ b/tests/pkd/pkd_daemon.c
@@ -253,8 +253,10 @@ static int pkd_exec_hello(int fd, struct pkd_daemon_args *args) {
 
     if (type == PKD_RSA) {
         opts = SSH_BIND_OPTIONS_RSAKEY;
+#ifdef HAVE_DSA
     } else if (type == PKD_DSA) {
         opts = SSH_BIND_OPTIONS_DSAKEY;
+#endif
     } else if (type == PKD_ECDSA) {
         opts = SSH_BIND_OPTIONS_ECDSAKEY;
     } else {
diff --git a/tests/pkd/pkd_daemon.h b/tests/pkd/pkd_daemon.h
index 7f553fdf..3107ed1e 100644
--- a/tests/pkd/pkd_daemon.h
+++ b/tests/pkd/pkd_daemon.h
@@ -10,7 +10,9 @@
 
 enum pkd_hostkey_type_e {
     PKD_RSA,
+#ifdef HAVE_DSA
     PKD_DSA,
+#endif
     PKD_ECDSA
 };
 
diff --git a/tests/pkd/pkd_hello.c b/tests/pkd/pkd_hello.c
index 4db8ee5c..e0c0cbf6 100644
--- a/tests/pkd/pkd_hello.c
+++ b/tests/pkd/pkd_hello.c
@@ -146,12 +146,14 @@ static int torture_pkd_setup_rsa(void **state) {
     return 0;
 }
 
+#ifdef HAVE_DSA
 static int torture_pkd_setup_dsa(void **state) {
     setup_dsa_key();
     *state = (void *) torture_pkd_setup(PKD_DSA, LIBSSH_DSA_TESTKEY);
 
     return 0;
 }
+#endif
 
 static int torture_pkd_setup_ecdsa_256(void **state) {
     setup_ecdsa_keys();
@@ -178,6 +180,7 @@ static int torture_pkd_setup_ecdsa_521(void **state) {
  * Test matrices: f(clientname, testname, ssh-command, setup-function, teardown-function).
  */
 
+#ifdef HAVE_DSA
 #define PKDTESTS_DEFAULT(f, client, cmd) \
     /* Default passes by server key type. */ \
     f(client, rsa_default,        cmd,  setup_rsa,        teardown) \
@@ -185,7 +188,16 @@ static int torture_pkd_setup_ecdsa_521(void **state) {
     f(client, ecdsa_256_default,  cmd,  setup_ecdsa_256,  teardown) \
     f(client, ecdsa_384_default,  cmd,  setup_ecdsa_384,  teardown) \
     f(client, ecdsa_521_default,  cmd,  setup_ecdsa_521,  teardown)
+#else
+#define PKDTESTS_DEFAULT(f, client, cmd) \
+    /* Default passes by server key type. */ \
+    f(client, rsa_default,        cmd,  setup_rsa,        teardown) \
+    f(client, ecdsa_256_default,  cmd,  setup_ecdsa_256,  teardown) \
+    f(client, ecdsa_384_default,  cmd,  setup_ecdsa_384,  teardown) \
+    f(client, ecdsa_521_default,  cmd,  setup_ecdsa_521,  teardown)
+#endif
 
+#ifdef HAVE_DSA
 #define PKDTESTS_KEX(f, client, kexcmd) \
     /* Kex algorithms. */ \
     f(client, rsa_curve25519_sha256,                  kexcmd("curve25519-sha256@libssh.org"),  setup_rsa,        teardown) \
@@ -218,7 +230,28 @@ static int torture_pkd_setup_ecdsa_521(void **state) {
     f(client, ecdsa_521_ecdh_sha2_nistp521,           kexcmd("ecdh-sha2-nistp521 "),           setup_ecdsa_521,  teardown) \
     f(client, ecdsa_521_diffie_hellman_group14_sha1,  kexcmd("diffie-hellman-group14-sha1"),   setup_ecdsa_521,  teardown) \
     f(client, ecdsa_521_diffie_hellman_group1_sha1,   kexcmd("diffie-hellman-group1-sha1"),    setup_ecdsa_521,  teardown)
+#else
+#define PKDTESTS_KEX(f, client, kexcmd) \
+    /* Kex algorithms. */ \
+    f(client, rsa_curve25519_sha256,                  kexcmd("curve25519-sha256@libssh.org"),  setup_rsa,        teardown) \
+    f(client, rsa_ecdh_sha2_nistp256,                 kexcmd("ecdh-sha2-nistp256 "),           setup_rsa,        teardown) \
+    f(client, rsa_diffie_hellman_group14_sha1,        kexcmd("diffie-hellman-group14-sha1"),   setup_rsa,        teardown) \
+    f(client, rsa_diffie_hellman_group1_sha1,         kexcmd("diffie-hellman-group1-sha1"),    setup_rsa,        teardown) \
+    f(client, ecdsa_256_curve25519_sha256,            kexcmd("curve25519-sha256@libssh.org"),  setup_ecdsa_256,  teardown) \
+    f(client, ecdsa_256_ecdh_sha2_nistp256,           kexcmd("ecdh-sha2-nistp256 "),           setup_ecdsa_256,  teardown) \
+    f(client, ecdsa_256_diffie_hellman_group14_sha1,  kexcmd("diffie-hellman-group14-sha1"),   setup_ecdsa_256,  teardown) \
+    f(client, ecdsa_256_diffie_hellman_group1_sha1,   kexcmd("diffie-hellman-group1-sha1"),    setup_ecdsa_256,  teardown) \
+    f(client, ecdsa_384_curve25519_sha256,            kexcmd("curve25519-sha256@libssh.org"),  setup_ecdsa_384,  teardown) \
+    f(client, ecdsa_384_ecdh_sha2_nistp256,           kexcmd("ecdh-sha2-nistp256 "),           setup_ecdsa_384,  teardown) \
+    f(client, ecdsa_384_diffie_hellman_group14_sha1,  kexcmd("diffie-hellman-group14-sha1"),   setup_ecdsa_384,  teardown) \
+    f(client, ecdsa_384_diffie_hellman_group1_sha1,   kexcmd("diffie-hellman-group1-sha1"),    setup_ecdsa_384,  teardown) \
+    f(client, ecdsa_521_curve25519_sha256,            kexcmd("curve25519-sha256@libssh.org"),  setup_ecdsa_521,  teardown) \
+    f(client, ecdsa_521_ecdh_sha2_nistp256,           kexcmd("ecdh-sha2-nistp256 "),           setup_ecdsa_521,  teardown) \
+    f(client, ecdsa_521_diffie_hellman_group14_sha1,  kexcmd("diffie-hellman-group14-sha1"),   setup_ecdsa_521,  teardown) \
+    f(client, ecdsa_521_diffie_hellman_group1_sha1,   kexcmd("diffie-hellman-group1-sha1"),    setup_ecdsa_521,  teardown)
+#endif
 
+#ifdef HAVE_DSA
 #define PKDTESTS_CIPHER(f, client, ciphercmd) \
     /* Ciphers. */ \
     f(client, rsa_3des_cbc,            ciphercmd("3des-cbc"),      setup_rsa,        teardown) \
@@ -251,7 +284,36 @@ static int torture_pkd_setup_ecdsa_521(void **state) {
     f(client, ecdsa_521_aes256_cbc,    ciphercmd("aes256-cbc"),    setup_ecdsa_521,  teardown) \
     f(client, ecdsa_521_aes256_ctr,    ciphercmd("aes256-ctr"),    setup_ecdsa_521,  teardown) \
     f(client, ecdsa_521_blowfish_cbc,  ciphercmd("blowfish-cbc"),  setup_ecdsa_521,  teardown)
+#else
+#define PKDTESTS_CIPHER(f, client, ciphercmd) \
+    /* Ciphers. */ \
+    f(client, rsa_3des_cbc,            ciphercmd("3des-cbc"),      setup_rsa,        teardown) \
+    f(client, rsa_aes128_cbc,          ciphercmd("aes128-cbc"),    setup_rsa,        teardown) \
+    f(client, rsa_aes128_ctr,          ciphercmd("aes128-ctr"),    setup_rsa,        teardown) \
+    f(client, rsa_aes256_cbc,          ciphercmd("aes256-cbc"),    setup_rsa,        teardown) \
+    f(client, rsa_aes256_ctr,          ciphercmd("aes256-ctr"),    setup_rsa,        teardown) \
+    f(client, rsa_blowfish_cbc,        ciphercmd("blowfish-cbc"),  setup_rsa,        teardown) \
+    f(client, ecdsa_256_3des_cbc,      ciphercmd("3des-cbc"),      setup_ecdsa_256,  teardown) \
+    f(client, ecdsa_256_aes128_cbc,    ciphercmd("aes128-cbc"),    setup_ecdsa_256,  teardown) \
+    f(client, ecdsa_256_aes128_ctr,    ciphercmd("aes128-ctr"),    setup_ecdsa_256,  teardown) \
+    f(client, ecdsa_256_aes256_cbc,    ciphercmd("aes256-cbc"),    setup_ecdsa_256,  teardown) \
+    f(client, ecdsa_256_aes256_ctr,    ciphercmd("aes256-ctr"),    setup_ecdsa_256,  teardown) \
+    f(client, ecdsa_256_blowfish_cbc,  ciphercmd("blowfish-cbc"),  setup_ecdsa_256,  teardown) \
+    f(client, ecdsa_384_3des_cbc,      ciphercmd("3des-cbc"),      setup_ecdsa_384,  teardown) \
+    f(client, ecdsa_384_aes128_cbc,    ciphercmd("aes128-cbc"),    setup_ecdsa_384,  teardown) \
+    f(client, ecdsa_384_aes128_ctr,    ciphercmd("aes128-ctr"),    setup_ecdsa_384,  teardown) \
+    f(client, ecdsa_384_aes256_cbc,    ciphercmd("aes256-cbc"),    setup_ecdsa_384,  teardown) \
+    f(client, ecdsa_384_aes256_ctr,    ciphercmd("aes256-ctr"),    setup_ecdsa_384,  teardown) \
+    f(client, ecdsa_384_blowfish_cbc,  ciphercmd("blowfish-cbc"),  setup_ecdsa_384,  teardown) \
+    f(client, ecdsa_521_3des_cbc,      ciphercmd("3des-cbc"),      setup_ecdsa_521,  teardown) \
+    f(client, ecdsa_521_aes128_cbc,    ciphercmd("aes128-cbc"),    setup_ecdsa_521,  teardown) \
+    f(client, ecdsa_521_aes128_ctr,    ciphercmd("aes128-ctr"),    setup_ecdsa_521,  teardown) \
+    f(client, ecdsa_521_aes256_cbc,    ciphercmd("aes256-cbc"),    setup_ecdsa_521,  teardown) \
+    f(client, ecdsa_521_aes256_ctr,    ciphercmd("aes256-ctr"),    setup_ecdsa_521,  teardown) \
+    f(client, ecdsa_521_blowfish_cbc,  ciphercmd("blowfish-cbc"),  setup_ecdsa_521,  teardown)
+#endif
 
+#ifdef HAVE_DSA
 #define PKDTESTS_CIPHER_OPENSSHONLY(f, client, ciphercmd) \
     /* Ciphers. */ \
     f(client, rsa_aes192_cbc,          ciphercmd("aes192-cbc"),    setup_rsa,        teardown) \
@@ -264,7 +326,20 @@ static int torture_pkd_setup_ecdsa_521(void **state) {
     f(client, ecdsa_384_aes192_ctr,    ciphercmd("aes192-ctr"),    setup_ecdsa_384,  teardown) \
     f(client, ecdsa_521_aes192_cbc,    ciphercmd("aes192-cbc"),    setup_ecdsa_521,  teardown) \
     f(client, ecdsa_521_aes192_ctr,    ciphercmd("aes192-ctr"),    setup_ecdsa_521,  teardown)
+#else
+#define PKDTESTS_CIPHER_OPENSSHONLY(f, client, ciphercmd) \
+    /* Ciphers. */ \
+    f(client, rsa_aes192_cbc,          ciphercmd("aes192-cbc"),    setup_rsa,        teardown) \
+    f(client, rsa_aes192_ctr,          ciphercmd("aes192-ctr"),    setup_rsa,        teardown) \
+    f(client, ecdsa_256_aes192_cbc,    ciphercmd("aes192-cbc"),    setup_ecdsa_256,  teardown) \
+    f(client, ecdsa_256_aes192_ctr,    ciphercmd("aes192-ctr"),    setup_ecdsa_256,  teardown) \
+    f(client, ecdsa_384_aes192_cbc,    ciphercmd("aes192-cbc"),    setup_ecdsa_384,  teardown) \
+    f(client, ecdsa_384_aes192_ctr,    ciphercmd("aes192-ctr"),    setup_ecdsa_384,  teardown) \
+    f(client, ecdsa_521_aes192_cbc,    ciphercmd("aes192-cbc"),    setup_ecdsa_521,  teardown) \
+    f(client, ecdsa_521_aes192_ctr,    ciphercmd("aes192-ctr"),    setup_ecdsa_521,  teardown)
+#endif
 
+#ifdef HAVE_DSA
 #define PKDTESTS_MAC(f, client, maccmd) \
     /* MACs. */ \
     f(client, rsa_hmac_sha1,            maccmd("hmac-sha1"),      setup_rsa,        teardown) \
@@ -282,6 +357,22 @@ static int torture_pkd_setup_ecdsa_521(void **state) {
     f(client, ecdsa_256_hmac_sha2_512,  maccmd("hmac-sha2-512"),  setup_ecdsa_256,  teardown) \
     f(client, ecdsa_384_hmac_sha2_512,  maccmd("hmac-sha2-512"),  setup_ecdsa_384,  teardown) \
     f(client, ecdsa_521_hmac_sha2_512,  maccmd("hmac-sha2-512"),  setup_ecdsa_521,  teardown)
+#else
+#define PKDTESTS_MAC(f, client, maccmd) \
+    /* MACs. */ \
+    f(client, rsa_hmac_sha1,            maccmd("hmac-sha1"),      setup_rsa,        teardown) \
+    f(client, ecdsa_256_hmac_sha1,      maccmd("hmac-sha1"),      setup_ecdsa_256,  teardown) \
+    f(client, ecdsa_384_hmac_sha1,      maccmd("hmac-sha1"),      setup_ecdsa_384,  teardown) \
+    f(client, ecdsa_521_hmac_sha1,      maccmd("hmac-sha1"),      setup_ecdsa_521,  teardown) \
+    f(client, rsa_hmac_sha2_256,        maccmd("hmac-sha2-256"),  setup_rsa,        teardown) \
+    f(client, ecdsa_256_hmac_sha2_256,  maccmd("hmac-sha2-256"),  setup_ecdsa_256,  teardown) \
+    f(client, ecdsa_384_hmac_sha2_256,  maccmd("hmac-sha2-256"),  setup_ecdsa_384,  teardown) \
+    f(client, ecdsa_521_hmac_sha2_256,  maccmd("hmac-sha2-256"),  setup_ecdsa_521,  teardown) \
+    f(client, rsa_hmac_sha2_512,        maccmd("hmac-sha2-512"),  setup_rsa,        teardown) \
+    f(client, ecdsa_256_hmac_sha2_512,  maccmd("hmac-sha2-512"),  setup_ecdsa_256,  teardown) \
+    f(client, ecdsa_384_hmac_sha2_512,  maccmd("hmac-sha2-512"),  setup_ecdsa_384,  teardown) \
+    f(client, ecdsa_521_hmac_sha2_512,  maccmd("hmac-sha2-512"),  setup_ecdsa_521,  teardown)
+#endif
 
 static void torture_pkd_client_noop(void **state) {
     struct pkd_state *pstate = (struct pkd_state *) (*state);
@@ -328,6 +419,7 @@ static void torture_pkd_runtest(const char *testname,
  * Actual test functions are emitted here.
  */
 
+#ifdef HAVE_DSA
 #define CLIENT_ID_FILE OPENSSH_DSA_TESTKEY
 PKDTESTS_DEFAULT(emit_keytest, openssh_dsa, OPENSSH_CMD)
 PKDTESTS_KEX(emit_keytest, openssh_dsa, OPENSSH_KEX_CMD)
@@ -335,6 +427,7 @@ PKDTESTS_CIPHER(emit_keytest, openssh_dsa, OPENSSH_CIPHER_CMD)
 PKDTESTS_CIPHER_OPENSSHONLY(emit_keytest, openssh_dsa, OPENSSH_CIPHER_CMD)
 PKDTESTS_MAC(emit_keytest, openssh_dsa, OPENSSH_MAC_CMD)
 #undef CLIENT_ID_FILE
+#endif
 
 #define CLIENT_ID_FILE OPENSSH_RSA_TESTKEY
 PKDTESTS_DEFAULT(emit_keytest, openssh_rsa, OPENSSH_CMD)
@@ -393,11 +486,13 @@ struct {
     const struct CMUnitTest test;
 } testmap[] = {
     /* OpenSSH */
+#ifdef HAVE_DSA
     PKDTESTS_DEFAULT(emit_testmap, openssh_dsa, OPENSSH_CMD)
     PKDTESTS_KEX(emit_testmap, openssh_dsa, OPENSSH_KEX_CMD)
     PKDTESTS_CIPHER(emit_testmap, openssh_dsa, OPENSSH_CIPHER_CMD)
     PKDTESTS_CIPHER_OPENSSHONLY(emit_testmap, openssh_dsa, OPENSSH_CIPHER_CMD)
     PKDTESTS_MAC(emit_testmap, openssh_dsa, OPENSSH_MAC_CMD)
+#endif
 
     PKDTESTS_DEFAULT(emit_testmap, openssh_rsa, OPENSSH_CMD)
     PKDTESTS_KEX(emit_testmap, openssh_rsa, OPENSSH_KEX_CMD)
@@ -438,11 +533,13 @@ static int pkd_run_tests(void) {
     int tindex = 0;
 
     const struct CMUnitTest openssh_tests[] = {
+#ifdef HAVE_DSA
         PKDTESTS_DEFAULT(emit_unit_test_comma, openssh_dsa, OPENSSH_CMD)
         PKDTESTS_KEX(emit_unit_test_comma, openssh_dsa, OPENSSH_KEX_CMD)
         PKDTESTS_CIPHER(emit_unit_test_comma, openssh_dsa, OPENSSH_CIPHER_CMD)
         PKDTESTS_CIPHER_OPENSSHONLY(emit_unit_test_comma, openssh_dsa, OPENSSH_CIPHER_CMD)
         PKDTESTS_MAC(emit_unit_test_comma, openssh_dsa, OPENSSH_MAC_CMD)
+#endif
 
         PKDTESTS_DEFAULT(emit_unit_test_comma, openssh_rsa, OPENSSH_CMD)
         PKDTESTS_KEX(emit_unit_test_comma, openssh_rsa, OPENSSH_KEX_CMD)
@@ -546,7 +643,9 @@ static int pkd_run_tests(void) {
 
     /* Clean up any server keys that were generated. */
     cleanup_rsa_key();
+#ifdef HAVE_DSA
     cleanup_dsa_key();
+#endif
     cleanup_ecdsa_keys();
 
     return rc;
diff --git a/tests/pkd/pkd_keyutil.c b/tests/pkd/pkd_keyutil.c
index e1e1ecb8..7cb2ed48 100644
--- a/tests/pkd/pkd_keyutil.c
+++ b/tests/pkd/pkd_keyutil.c
@@ -27,6 +27,7 @@ void setup_rsa_key() {
     assert_int_equal(rc, 0);
 }
 
+#ifdef HAVE_DSA
 void setup_dsa_key() {
     int rc = 0;
     if (access(LIBSSH_DSA_TESTKEY, F_OK) != 0) {
@@ -35,6 +36,7 @@ void setup_dsa_key() {
     }
     assert_int_equal(rc, 0);
 }
+#endif
 
 void setup_ecdsa_keys() {
     int rc = 0;
@@ -65,9 +67,11 @@ void cleanup_rsa_key() {
     cleanup_key(LIBSSH_RSA_TESTKEY, LIBSSH_RSA_TESTKEY ".pub");
 }
 
+#ifdef HAVE_DSA
 void cleanup_dsa_key() {
     cleanup_key(LIBSSH_DSA_TESTKEY, LIBSSH_DSA_TESTKEY ".pub");
 }
+#endif
 
 void cleanup_ecdsa_keys() {
     cleanup_key(LIBSSH_ECDSA_256_TESTKEY, LIBSSH_ECDSA_256_TESTKEY ".pub");
@@ -78,11 +82,13 @@ void cleanup_ecdsa_keys() {
 void setup_openssh_client_keys() {
     int rc = 0;
 
+#ifdef HAVE_DSA
     if (access(OPENSSH_DSA_TESTKEY, F_OK) != 0) {
         rc = system_checked(OPENSSH_KEYGEN " -t dsa -q -N \"\" -f "
                             OPENSSH_DSA_TESTKEY);
     }
     assert_int_equal(rc, 0);
+#endif
 
     if (access(OPENSSH_RSA_TESTKEY, F_OK) != 0) {
         rc = system_checked(OPENSSH_KEYGEN " -t rsa -q -N \"\" -f "
@@ -116,7 +122,9 @@ void setup_openssh_client_keys() {
 }
 
 void cleanup_openssh_client_keys() {
+#ifdef HAVE_DSA
     cleanup_key(OPENSSH_DSA_TESTKEY, OPENSSH_DSA_TESTKEY ".pub");
+#endif
     cleanup_key(OPENSSH_RSA_TESTKEY, OPENSSH_RSA_TESTKEY ".pub");
     cleanup_key(OPENSSH_ECDSA256_TESTKEY, OPENSSH_ECDSA256_TESTKEY ".pub");
     cleanup_key(OPENSSH_ECDSA384_TESTKEY, OPENSSH_ECDSA384_TESTKEY ".pub");
diff --git a/tests/pkd/pkd_keyutil.h b/tests/pkd/pkd_keyutil.h
index 8e9de009..3d0ae5a7 100644
--- a/tests/pkd/pkd_keyutil.h
+++ b/tests/pkd/pkd_keyutil.h
@@ -7,22 +7,32 @@
 #ifndef __PKD_KEYUTIL_H__
 #define __PKD_KEYUTIL_H__
 
+#include "config.h"
+
 /* Server keys. */
+#ifdef HAVE_DSA
 #define LIBSSH_DSA_TESTKEY        "libssh_testkey.id_dsa"
+#endif
 #define LIBSSH_RSA_TESTKEY        "libssh_testkey.id_rsa"
 #define LIBSSH_ECDSA_256_TESTKEY  "libssh_testkey.id_ecdsa256"
 #define LIBSSH_ECDSA_384_TESTKEY  "libssh_testkey.id_ecdsa384"
 #define LIBSSH_ECDSA_521_TESTKEY  "libssh_testkey.id_ecdsa521"
 
+#ifdef HAVE_DSA
 void setup_dsa_key(void);
+#endif
 void setup_rsa_key(void);
 void setup_ecdsa_keys(void);
+#ifdef HAVE_DSA
 void cleanup_dsa_key(void);
+#endif
 void cleanup_rsa_key(void);
 void cleanup_ecdsa_keys(void);
 
 /* Client keys. */
+#ifdef HAVE_DSA
 #define OPENSSH_DSA_TESTKEY       "openssh_testkey.id_dsa"
+#endif
 #define OPENSSH_RSA_TESTKEY       "openssh_testkey.id_rsa"
 #define OPENSSH_ECDSA256_TESTKEY  "openssh_testkey.id_ecdsa256"
 #define OPENSSH_ECDSA384_TESTKEY  "openssh_testkey.id_ecdsa384"