Rewrite SRTP extension using CBB/CBS and the new extension framework.

input + ok beck@, jsing@

1 files changed, 402 insertions, 1 deletions

diff --git a/src/regress/lib/libssl/tlsext/tlsexttest.c b/src/regress/lib/libssl/tlsext/tlsexttest.c
index d3858e4c50..1b2820d78b 100644
--- a/src/regress/lib/libssl/tlsext/tlsexttest.c
+++ b/src/regress/lib/libssl/tlsext/tlsexttest.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: tlsexttest.c,v 1.14 2017/08/27 02:17:51 beck Exp $ */
+/* $OpenBSD: tlsexttest.c,v 1.15 2017/08/27 02:58:04 doug Exp $ */
 /*
  * Copyright (c) 2017 Joel Sing <jsing@openbsd.org>
  * Copyright (c) 2017 Doug Hogan <doug@openbsd.org>
@@ -2257,6 +2257,400 @@ test_tlsext_sessionticket_serverhello(void)
         return (failure);
 }
 
+#ifndef OPENSSL_NO_SRTP
+/*
+ * Supported Secure Real-time Transport Protocol (RFC 5764 section 4.1.1)
+ */
+
+/* Colon separated string values */
+const char *tlsext_srtp_single_profile = "SRTP_AES128_CM_SHA1_80";
+const char *tlsext_srtp_multiple_profiles = "SRTP_AES128_CM_SHA1_80:SRTP_AES128_CM_SHA1_32";
+
+const char *tlsext_srtp_aes128cmsha80 = "SRTP_AES128_CM_SHA1_80";
+const char *tlsext_srtp_aes128cmsha32 = "SRTP_AES128_CM_SHA1_32";
+
+const uint8_t tlsext_srtp_single[] = {
+        /* SRTPProtectionProfile SRTPProtectionProfiles<2..2^16-1> */
+        0x00, 0x02, /* len */
+        0x00, 0x01, /* SRTP_AES128_CM_SHA1_80 */
+        0x00        /* opaque srtp_mki<0..255> */
+};
+
+const uint8_t tlsext_srtp_multiple[] = {
+        /* SRTPProtectionProfile SRTPProtectionProfiles<2..2^16-1> */
+        0x00, 0x04, /* len */
+        0x00, 0x01, /* SRTP_AES128_CM_SHA1_80 */
+        0x00, 0x02, /* SRTP_AES128_CM_SHA1_32 */
+        0x00    /* opaque srtp_mki<0..255> */
+};
+
+const uint8_t tlsext_srtp_multiple_invalid[] = {
+        /* SRTPProtectionProfile SRTPProtectionProfiles<2..2^16-1> */
+        0x00, 0x04, /* len */
+        0x00, 0x08, /* arbitrary value not found in known profiles */
+        0x00, 0x09, /* arbitrary value not found in known profiles */
+        0x00    /* opaque srtp_mki<0..255> */
+};
+
+const uint8_t tlsext_srtp_single_invalid[] = {
+        /* SRTPProtectionProfile SRTPProtectionProfiles<2..2^16-1> */
+        0x00, 0x02, /* len */
+        0x00, 0x08, /* arbitrary value not found in known profiles */
+        0x00    /* opaque srtp_mki<0..255> */
+};
+
+const uint8_t tlsext_srtp_multiple_one_valid[] = {
+        /* SRTPProtectionProfile SRTPProtectionProfiles<2..2^16-1> */
+        0x00, 0x04, /* len */
+        0x00, 0x08, /* arbitrary value not found in known profiles */
+        0x00, 0x02, /* SRTP_AES128_CM_SHA1_32 */
+        0x00        /* opaque srtp_mki<0..255> */
+};
+
+static int
+test_tlsext_srtp_clienthello(void)
+{
+        SRTP_PROTECTION_PROFILE *prof;
+        SSL_CTX *ssl_ctx = NULL;
+        SSL *ssl = NULL;
+        uint8_t *data = NULL;
+        CBB cbb;
+        CBS cbs;
+        int failure, alert;
+        size_t dlen;
+
+        CBB_init(&cbb, 0);
+
+        failure = 1;
+
+        /* SRTP is for DTLS */
+        if ((ssl_ctx = SSL_CTX_new(DTLSv1_client_method())) == NULL)
+                errx(1, "failed to create SSL_CTX");
+        if ((ssl = SSL_new(ssl_ctx)) == NULL)
+                errx(1, "failed to create SSL");
+
+        /* By default, we don't need this */
+        if (tlsext_srtp_clienthello_needs(ssl)) {
+                FAIL("clienthello should not need SRTP by default\n");
+                goto err;
+        }
+
+        if (SSL_set_tlsext_use_srtp(ssl, tlsext_srtp_single_profile) != 0) {
+                FAIL("should be able to set a single SRTP\n");
+                goto err;
+        }
+        if (!tlsext_srtp_clienthello_needs(ssl)) {
+                FAIL("clienthello should need SRTP\n");
+                goto err;
+        }
+
+        /* Make sure we can build the clienthello with a single profile. */
+
+        if (!tlsext_srtp_clienthello_build(ssl, &cbb)) {
+                FAIL("clienthello failed to build SRTP\n");
+                goto err;
+        }
+        if (!CBB_finish(&cbb, &data, &dlen))
+                errx(1, "failed to finish CBB");
+
+        if (dlen != sizeof(tlsext_srtp_single)) {
+                FAIL("got clienthello SRTP with length %zu, "
+                    "want length %zu\n", dlen,
+                    sizeof(tlsext_srtp_single));
+                compare_data(data, dlen, tlsext_srtp_single,
+                    sizeof(tlsext_srtp_single));
+                goto err;
+        }
+        if (memcmp(data, tlsext_srtp_single, dlen) != 0) {
+                FAIL("clienthello SRTP differs:\n");
+                compare_data(data, dlen, tlsext_srtp_single,
+                    sizeof(tlsext_srtp_single));
+                goto err;
+        }
+
+        CBB_cleanup(&cbb);
+        CBB_init(&cbb, 0);
+        free(data);
+        data = NULL;
+
+        /* Make sure we can parse the single profile. */
+
+        if (SSL_get_selected_srtp_profile(ssl) != NULL) {
+                FAIL("SRTP profile should not be set yet\n");
+                goto err;
+        }
+
+        CBS_init(&cbs, tlsext_srtp_single, sizeof(tlsext_srtp_single));
+        if (!tlsext_srtp_clienthello_parse(ssl, &cbs, &alert)) {
+                FAIL("failed to parse SRTP\n");
+                goto err;
+        }
+
+        if ((prof = SSL_get_selected_srtp_profile(ssl)) == NULL) {
+                FAIL("SRTP profile should be set now\n");
+                goto err;
+        }
+        if (strcmp(prof->name, tlsext_srtp_aes128cmsha80) != 0) {
+                FAIL("SRTP profile was not set properly\n");
+                goto err;
+        }
+
+        if (!tlsext_srtp_serverhello_needs(ssl)) {
+                FAIL("should send server extension when profile selected\n");
+                goto err;
+        }
+
+        /* Make sure we can build the clienthello with multiple entries. */
+
+        if (SSL_set_tlsext_use_srtp(ssl, tlsext_srtp_multiple_profiles) != 0) {
+                FAIL("should be able to set SRTP to multiple profiles\n");
+                goto err;
+        }
+        if (!tlsext_srtp_clienthello_needs(ssl)) {
+                FAIL("clienthello should need SRTP by now\n");
+                goto err;
+        }
+
+        if (!tlsext_srtp_clienthello_build(ssl, &cbb)) {
+                FAIL("clienthello failed to build SRTP\n");
+                goto err;
+        }
+        if (!CBB_finish(&cbb, &data, &dlen))
+                errx(1, "failed to finish CBB");
+
+        if (dlen != sizeof(tlsext_srtp_multiple)) {
+                FAIL("got clienthello SRTP with length %zu, "
+                    "want length %zu\n", dlen,
+                    sizeof(tlsext_srtp_multiple));
+                compare_data(data, dlen, tlsext_srtp_multiple,
+                    sizeof(tlsext_srtp_multiple));
+                goto err;
+        }
+        if (memcmp(data, tlsext_srtp_multiple, dlen) != 0) {
+                FAIL("clienthello SRTP differs:\n");
+                compare_data(data, dlen, tlsext_srtp_multiple,
+                    sizeof(tlsext_srtp_multiple));
+                goto err;
+        }
+
+        CBB_cleanup(&cbb);
+        CBB_init(&cbb, 0);
+        free(data);
+        data = NULL;
+
+        /* Make sure we can parse multiple profiles (selects server preferred) */
+
+        ssl->internal->srtp_profile = NULL;
+
+        CBS_init(&cbs, tlsext_srtp_multiple,
+            sizeof(tlsext_srtp_multiple));
+        if (!tlsext_srtp_clienthello_parse(ssl, &cbs, &alert)) {
+                FAIL("failed to parse SRTP\n");
+                goto err;
+        }
+
+        if ((prof = SSL_get_selected_srtp_profile(ssl)) == NULL) {
+                FAIL("SRTP profile should be set now\n");
+                goto err;
+        }
+        if (strcmp(prof->name, tlsext_srtp_aes128cmsha80) != 0) {
+                FAIL("SRTP profile was not set properly\n");
+                goto err;
+        }
+
+        if (!tlsext_srtp_serverhello_needs(ssl)) {
+                FAIL("should send server extension when profile selected\n");
+                goto err;
+        }
+
+        /*
+         * Make sure we can parse the clienthello with multiple entries
+         * where one is unknown.
+         */
+        ssl->internal->srtp_profile = NULL;
+
+        CBS_init(&cbs, tlsext_srtp_multiple_one_valid,
+            sizeof(tlsext_srtp_multiple_one_valid));
+        if (!tlsext_srtp_clienthello_parse(ssl, &cbs, &alert)) {
+                FAIL("failed to parse SRTP\n");
+                goto err;
+        }
+
+        if ((prof = SSL_get_selected_srtp_profile(ssl)) == NULL) {
+                FAIL("SRTP profile should be set now\n");
+                goto err;
+        }
+        if (strcmp(prof->name, tlsext_srtp_aes128cmsha32) != 0) {
+                FAIL("SRTP profile was not set properly\n");
+                goto err;
+        }
+
+        if (!tlsext_srtp_serverhello_needs(ssl)) {
+                FAIL("should send server extension when profile selected\n");
+                goto err;
+        }
+
+        /* Make sure we fall back to negotiated when none work. */
+
+        ssl->internal->srtp_profile = NULL;
+
+        CBS_init(&cbs, tlsext_srtp_multiple_invalid,
+            sizeof(tlsext_srtp_multiple_invalid));
+        if (!tlsext_srtp_clienthello_parse(ssl, &cbs, &alert)) {
+                FAIL("should be able to fall back to negotiated\n");
+                goto err;
+        }
+
+        /* If we fallback, the server should NOT send the extension. */
+        if (SSL_get_selected_srtp_profile(ssl) != NULL) {
+                FAIL("should not have selected a profile when none found\n");
+                goto err;
+        }
+        if (tlsext_srtp_serverhello_needs(ssl)) {
+                FAIL("should not send server tlsext when no profile found\n");
+                goto err;
+        }
+
+        failure = 0;
+
+ err:
+        CBB_cleanup(&cbb);
+        SSL_CTX_free(ssl_ctx);
+        SSL_free(ssl);
+        free(data);
+
+        return (failure);
+}
+
+static int
+test_tlsext_srtp_serverhello(void)
+{
+        SRTP_PROTECTION_PROFILE *prof;
+        SSL_CTX *ssl_ctx = NULL;
+        SSL *ssl = NULL;
+        uint8_t *data = NULL;
+        CBB cbb;
+        CBS cbs;
+        int failure, alert;
+        size_t dlen;
+
+        CBB_init(&cbb, 0);
+
+        failure = 1;
+
+        /* SRTP is for DTLS */
+        if ((ssl_ctx = SSL_CTX_new(DTLSv1_client_method())) == NULL)
+                errx(1, "failed to create SSL_CTX");
+        if ((ssl = SSL_new(ssl_ctx)) == NULL)
+                errx(1, "failed to create SSL");
+
+        /* By default, we don't need this */
+        if (tlsext_srtp_serverhello_needs(ssl)) {
+                FAIL("serverhello should not need SRTP by default\n");
+                goto err;
+        }
+
+        if (srtp_find_profile_by_name((char *)tlsext_srtp_aes128cmsha80, &prof,
+            strlen(tlsext_srtp_aes128cmsha80))) {
+                FAIL("should be able to find the given profile\n");
+                goto err;
+        }
+        ssl->internal->srtp_profile = prof;
+        if (!tlsext_srtp_serverhello_needs(ssl)) {
+                FAIL("serverhello should need SRTP by now\n");
+                goto err;
+        }
+
+        /* Make sure we can build the serverhello with a single profile. */
+
+        if (!tlsext_srtp_serverhello_build(ssl, &cbb)) {
+                FAIL("serverhello failed to build SRTP\n");
+                goto err;
+        }
+        if (!CBB_finish(&cbb, &data, &dlen))
+                errx(1, "failed to finish CBB");
+
+        if (dlen != sizeof(tlsext_srtp_single)) {
+                FAIL("got serverhello SRTP with length %zu, "
+                    "want length %zu\n", dlen,
+                    sizeof(tlsext_srtp_single));
+                compare_data(data, dlen, tlsext_srtp_single,
+                    sizeof(tlsext_srtp_single));
+                goto err;
+        }
+        if (memcmp(data, tlsext_srtp_single, dlen) != 0) {
+                FAIL("serverhello SRTP differs:\n");
+                compare_data(data, dlen, tlsext_srtp_single,
+                    sizeof(tlsext_srtp_single));
+                goto err;
+        }
+
+        CBB_cleanup(&cbb);
+        CBB_init(&cbb, 0);
+        free(data);
+        data = NULL;
+
+        /* Make sure we can parse the single profile. */
+        ssl->internal->srtp_profile = NULL;
+
+        if (SSL_get_selected_srtp_profile(ssl) != NULL) {
+                FAIL("SRTP profile should not be set yet\n");
+                goto err;
+        }
+
+        /* Setup the environment as if a client sent a list of profiles. */
+        if (SSL_set_tlsext_use_srtp(ssl, tlsext_srtp_multiple_profiles) != 0) {
+                FAIL("should be able to set multiple profiles in SRTP\n");
+                goto err;
+        }
+
+        CBS_init(&cbs, tlsext_srtp_single, sizeof(tlsext_srtp_single));
+        if (!tlsext_srtp_serverhello_parse(ssl, &cbs, &alert)) {
+                FAIL("failed to parse SRTP\n");
+                goto err;
+        }
+
+        if ((prof = SSL_get_selected_srtp_profile(ssl)) == NULL) {
+                FAIL("SRTP profile should be set now\n");
+                goto err;
+        }
+        if (strcmp(prof->name, tlsext_srtp_aes128cmsha80) != 0) {
+                FAIL("SRTP profile was not set properly\n");
+                goto err;
+        }
+
+        /* Make sure we cannot parse multiple profiles */
+        ssl->internal->srtp_profile = NULL;
+
+        CBS_init(&cbs, tlsext_srtp_multiple,
+            sizeof(tlsext_srtp_multiple));
+        if (tlsext_srtp_serverhello_parse(ssl, &cbs, &alert)) {
+                FAIL("should not find multiple entries from the server\n");
+                goto err;
+        }
+
+        /* Make sure we cannot parse a serverhello with unknown profile */
+        ssl->internal->srtp_profile = NULL;
+
+        CBS_init(&cbs, tlsext_srtp_single_invalid,
+            sizeof(tlsext_srtp_single_invalid));
+        if (tlsext_srtp_serverhello_parse(ssl, &cbs, &alert)) {
+                FAIL("should not be able to parse this\n");
+                goto err;
+        }
+
+        failure = 0;
+
+ err:
+        CBB_cleanup(&cbb);
+        SSL_CTX_free(ssl_ctx);
+        SSL_free(ssl);
+        free(data);
+
+        return (failure);
+}
+#endif /* OPENSSL_NO_SRTP */
+
 int
 main(int argc, char **argv)
 {
@@ -2288,5 +2682,12 @@ main(int argc, char **argv)
         failed |= test_tlsext_sessionticket_clienthello();
         failed |= test_tlsext_sessionticket_serverhello();
 
+#ifndef OPENSSL_NO_SRTP
+        failed |= test_tlsext_srtp_clienthello();
+        failed |= test_tlsext_srtp_serverhello();
+#else
+        fprintf(stderr, "Skipping SRTP tests due to OPENSSL_NO_SRTP\n");
+#endif
+
         return (failed);
 }