Add regress tests for DTLS handshake messages.

2 files changed, 375 insertions, 1 deletions

diff --git a/src/regress/lib/libssl/dtls/Makefile b/src/regress/lib/libssl/dtls/Makefile
index a8d888c882..739faf8b9e 100644
--- a/src/regress/lib/libssl/dtls/Makefile
+++ b/src/regress/lib/libssl/dtls/Makefile
@@ -1,6 +1,7 @@
-#       $OpenBSD: Makefile,v 1.5 2026/04/25 14:36:12 jsing Exp $
+#       $OpenBSD: Makefile,v 1.6 2026/06/06 08:13:50 jsing Exp $
 
 PROGS +=        dtlstest
+PROGS +=        dtls_handshake_msg_test
 PROGS +=        dtls_wire_test
 
 LDADD=          ${SSL_INT} -lcrypto
@@ -12,6 +13,7 @@ CFLAGS+=	-I${.CURDIR}/../../../../lib/libssl
 
 REGRESS_TARGETS= \
         regress-dtlstest \
+        regress-dtls_handshake_msg_test \
         regress-dtls_wire_test
 
 # XXX(jsing): use CA root and chain
@@ -21,6 +23,9 @@ regress-dtlstest: dtlstest
             ${.CURDIR}/../../libssl/certs/server1-rsa.pem \
             ${.CURDIR}/../../libssl/certs/ca-int-rsa.pem
 
+regress-dtls_handshake_msg_test: dtls_handshake_msg_test
+        ./dtls_handshake_msg_test
+
 regress-dtls_wire_test: dtls_wire_test
         ./dtls_wire_test
 
diff --git a/src/regress/lib/libssl/dtls/dtls_handshake_msg_test.c b/src/regress/lib/libssl/dtls/dtls_handshake_msg_test.c
new file mode 100644
index 0000000000..4fbc8d8803
--- /dev/null
+++ b/src/regress/lib/libssl/dtls/dtls_handshake_msg_test.c
@@ -0,0 +1,369 @@
+/* $OpenBSD: dtls_handshake_msg_test.c,v 1.1 2026/06/06 08:13:50 jsing Exp $ */
+/*
+ * Copyright (c) 2026 Joel Sing <jsing@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <stdio.h>
+#include <string.h>
+
+#include <openssl/ssl3.h>
+
+#include "bytestring.h"
+#include "dtls12_internal.h"
+
+static void
+hexdump(const unsigned char *buf, size_t len)
+{
+        size_t i;
+
+        for (i = 1; i <= len; i++)
+                fprintf(stderr, " 0x%02hhx,%s", buf[i - 1], i % 8 ? "" : "\n");
+
+        fprintf(stderr, "\n");
+}
+
+static const uint8_t dtls12_hs_msg_data[] = {
+        0x01, 0x00, 0x01, 0x00, 0xca, 0xfe, 0x00, 0x00,
+        0x00, 0x00, 0x01, 0x00, 0x00, 0x01, 0x02, 0x03,
+        0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b,
+        0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11, 0x12, 0x13,
+        0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b,
+        0x1c, 0x1d, 0x1e, 0x1f, 0x20, 0x21, 0x22, 0x23,
+        0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b,
+        0x2c, 0x2d, 0x2e, 0x2f, 0x30, 0x31, 0x32, 0x33,
+        0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3b,
+        0x3c, 0x3d, 0x3e, 0x3f, 0x40, 0x41, 0x42, 0x43,
+        0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4a, 0x4b,
+        0x4c, 0x4d, 0x4e, 0x4f, 0x50, 0x51, 0x52, 0x53,
+        0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a, 0x5b,
+        0x5c, 0x5d, 0x5e, 0x5f, 0x60, 0x61, 0x62, 0x63,
+        0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6a, 0x6b,
+        0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72, 0x73,
+        0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, 0x7b,
+        0x7c, 0x7d, 0x7e, 0x7f, 0x80, 0x81, 0x82, 0x83,
+        0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a, 0x8b,
+        0x8c, 0x8d, 0x8e, 0x8f, 0x90, 0x91, 0x92, 0x93,
+        0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9a, 0x9b,
+        0x9c, 0x9d, 0x9e, 0x9f, 0xa0, 0xa1, 0xa2, 0xa3,
+        0xa4, 0xa5, 0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xab,
+        0xac, 0xad, 0xae, 0xaf, 0xb0, 0xb1, 0xb2, 0xb3,
+        0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xbb,
+        0xbc, 0xbd, 0xbe, 0xbf, 0xc0, 0xc1, 0xc2, 0xc3,
+        0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xcb,
+        0xcc, 0xcd, 0xce, 0xcf, 0xd0, 0xd1, 0xd2, 0xd3,
+        0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xdb,
+        0xdc, 0xdd, 0xde, 0xdf, 0xe0, 0xe1, 0xe2, 0xe3,
+        0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea, 0xeb,
+        0xec, 0xed, 0xee, 0xef, 0xf0, 0xf1, 0xf2, 0xf3,
+        0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9, 0xfa, 0xfb,
+        0xfc, 0xfd, 0xfe, 0xff,
+};
+
+static const uint8_t dtls12_hm_content[] = {
+        0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+        0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
+        0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
+        0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
+        0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
+        0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
+        0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
+        0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
+        0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
+        0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
+        0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,
+        0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f,
+        0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,
+        0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f,
+        0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77,
+        0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f,
+        0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
+        0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,
+        0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97,
+        0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f,
+        0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,
+        0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf,
+        0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7,
+        0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf,
+        0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7,
+        0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf,
+        0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7,
+        0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf,
+        0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7,
+        0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef,
+        0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7,
+        0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff,
+};
+
+static const uint8_t dtls12_hs_msg_frag_0[] = {
+        0x01, 0x00, 0x01, 0x00, 0xca, 0xfe, 0x00, 0x00,
+        0x00, 0x00, 0x00, 0x40, 0x00, 0x01, 0x02, 0x03,
+        0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b,
+        0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11, 0x12, 0x13,
+        0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b,
+        0x1c, 0x1d, 0x1e, 0x1f, 0x20, 0x21, 0x22, 0x23,
+        0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b,
+        0x2c, 0x2d, 0x2e, 0x2f, 0x30, 0x31, 0x32, 0x33,
+        0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3b,
+        0x3c, 0x3d, 0x3e, 0x3f,
+};
+
+static const uint8_t dtls12_hs_msg_frag_1[] = {
+        0x01, 0x00, 0x01, 0x00, 0xca, 0xfe, 0x00, 0x00,
+        0x00, 0x00, 0x00, 0x20, 0x00, 0x01, 0x02, 0x03,
+        0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b,
+        0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11, 0x12, 0x13,
+        0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b,
+        0x1c, 0x1d, 0x1e, 0x1f,
+};
+
+static const uint8_t dtls12_hs_msg_frag_2[] = {
+        0x01, 0x00, 0x01, 0x00, 0xca, 0xfe, 0x00, 0x00,
+        0x20, 0x00, 0x00, 0x80, 0x20, 0x21, 0x22, 0x23,
+        0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b,
+        0x2c, 0x2d, 0x2e, 0x2f, 0x30, 0x31, 0x32, 0x33,
+        0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3b,
+        0x3c, 0x3d, 0x3e, 0x3f, 0x40, 0x41, 0x42, 0x43,
+        0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4a, 0x4b,
+        0x4c, 0x4d, 0x4e, 0x4f, 0x50, 0x51, 0x52, 0x53,
+        0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a, 0x5b,
+        0x5c, 0x5d, 0x5e, 0x5f, 0x60, 0x61, 0x62, 0x63,
+        0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6a, 0x6b,
+        0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72, 0x73,
+        0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, 0x7b,
+        0x7c, 0x7d, 0x7e, 0x7f, 0x80, 0x81, 0x82, 0x83,
+        0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a, 0x8b,
+        0x8c, 0x8d, 0x8e, 0x8f, 0x90, 0x91, 0x92, 0x93,
+        0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9a, 0x9b,
+        0x9c, 0x9d, 0x9e, 0x9f,
+};
+
+static const uint8_t dtls12_hs_msg_frag_3[] = {
+        0x01, 0x00, 0x01, 0x00, 0xca, 0xfe, 0x00, 0x00,
+        0xa0, 0x00, 0x00, 0x60, 0xa0, 0xa1, 0xa2, 0xa3,
+        0xa4, 0xa5, 0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xab,
+        0xac, 0xad, 0xae, 0xaf, 0xb0, 0xb1, 0xb2, 0xb3,
+        0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xbb,
+        0xbc, 0xbd, 0xbe, 0xbf, 0xc0, 0xc1, 0xc2, 0xc3,
+        0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xcb,
+        0xcc, 0xcd, 0xce, 0xcf, 0xd0, 0xd1, 0xd2, 0xd3,
+        0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xdb,
+        0xdc, 0xdd, 0xde, 0xdf, 0xe0, 0xe1, 0xe2, 0xe3,
+        0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea, 0xeb,
+        0xec, 0xed, 0xee, 0xef, 0xf0, 0xf1, 0xf2, 0xf3,
+        0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9, 0xfa, 0xfb,
+        0xfc, 0xfd, 0xfe, 0xff,
+};
+
+static int
+dtls_handshake_msg_test(void)
+{
+        struct dtls12_handshake_msg *hs_msg = NULL;
+        uint8_t *p;
+        int i;
+        CBB cbb;
+        CBS cbs;
+        int failed = 1;
+
+        memset(&cbb, 0, sizeof(cbb));
+
+        if ((hs_msg = dtls12_handshake_msg_new()) == NULL) {
+                fprintf(stderr, "FAIL: dtls12_handshake_msg_new\n");
+                goto failure;
+        }
+        if (!dtls12_handshake_msg_start(hs_msg, &cbb, SSL3_MT_CLIENT_HELLO,
+            0xcafe)) {
+                fprintf(stderr, "FAIL: dtls12_handshake_msg_start\n");
+                goto failure;
+        }
+        if (!CBB_add_space(&cbb, &p, 256)) {
+                fprintf(stderr, "FAIL: CBB_add_space\n");
+                goto failure;
+        }
+        for (i = 0; i < 256; i++)
+                p[i] = i;
+        if (!dtls12_handshake_msg_finish(hs_msg)) {
+                fprintf(stderr, "FAIL: dtls12_handshake_msg_finish\n");
+                goto failure;
+        }
+
+        dtls12_handshake_msg_data(hs_msg, &cbs);
+        if (CBS_len(&cbs) != sizeof(dtls12_hs_msg_data)) {
+                fprintf(stderr, "FAIL: handshake message data length = %zu, want %zu\n",
+                    CBS_len(&cbs), sizeof(dtls12_hs_msg_data));
+                goto failure;
+        }
+        if (memcmp(CBS_data(&cbs), dtls12_hs_msg_data, CBS_len(&cbs)) != 0) {
+                fprintf(stderr, "FAIL: got handshake message data:\n");
+                hexdump(CBS_data(&cbs), CBS_len(&cbs));
+                fprintf(stderr, "want handshake message data:\n");
+                hexdump(dtls12_hs_msg_data, CBS_len(&cbs));
+        }
+
+        dtls12_handshake_msg_content(hs_msg, &cbs);
+        if (CBS_len(&cbs) != sizeof(dtls12_hm_content)) {
+                fprintf(stderr, "FAIL: handshake message content length = %zu, want %zu\n",
+                    CBS_len(&cbs), sizeof(dtls12_hm_content));
+                goto failure;
+        }
+        if (memcmp(CBS_data(&cbs), dtls12_hm_content, CBS_len(&cbs)) != 0) {
+                fprintf(stderr, "FAIL: got handshake message content:\n");
+                hexdump(CBS_data(&cbs), CBS_len(&cbs));
+                fprintf(stderr, "want handshake message content:\n");
+                hexdump(dtls12_hm_content, CBS_len(&cbs));
+        }
+
+        if (!dtls12_handshake_msg_fragment_pending(hs_msg)) {
+                fprintf(stderr, "FAIL: handshake message should have pending fragments\n");
+                goto failure;
+        }
+        if (!dtls12_handshake_msg_fragment_build(hs_msg, 64, &cbs)) {
+                fprintf(stderr, "FAIL: failed to build handshake message fragment 0\n");
+                goto failure;
+        }
+        if (CBS_len(&cbs) != sizeof(dtls12_hs_msg_frag_0)) {
+                fprintf(stderr, "FAIL: handshake message fragment 0 length = %zu, want %zu\n",
+                    CBS_len(&cbs), sizeof(dtls12_hs_msg_frag_0));
+                goto failure;
+        }
+        if (memcmp(CBS_data(&cbs), dtls12_hs_msg_frag_0, CBS_len(&cbs)) != 0) {
+                fprintf(stderr, "FAIL: got handshake message fragment:\n");
+                hexdump(CBS_data(&cbs), CBS_len(&cbs));
+                fprintf(stderr, "want handshake message fragment:\n");
+                hexdump(dtls12_hs_msg_frag_0, CBS_len(&cbs));
+        }
+
+        if (!dtls12_handshake_msg_fragment_build(hs_msg, 32, &cbs)) {
+                fprintf(stderr, "FAIL: failed to build handshake message fragment 1\n");
+                goto failure;
+        }
+        if (CBS_len(&cbs) != sizeof(dtls12_hs_msg_frag_1)) {
+                fprintf(stderr, "FAIL: handshake message fragment 1 length = %zu, want %zu\n",
+                    CBS_len(&cbs), sizeof(dtls12_hs_msg_frag_1));
+                goto failure;
+        }
+        if (memcmp(CBS_data(&cbs), dtls12_hs_msg_frag_1, CBS_len(&cbs)) != 0) {
+                fprintf(stderr, "FAIL: got handshake message 1 fragment:\n");
+                hexdump(CBS_data(&cbs), CBS_len(&cbs));
+                fprintf(stderr, "want handshake message 1 fragment:\n");
+                hexdump(dtls12_hs_msg_frag_1, CBS_len(&cbs));
+        }
+
+        if (!dtls12_handshake_msg_fragment_build(hs_msg, 32, &cbs)) {
+                fprintf(stderr, "FAIL: failed to rebuild handshake message fragment 1\n");
+                goto failure;
+        }
+        if (CBS_len(&cbs) != sizeof(dtls12_hs_msg_frag_1)) {
+                fprintf(stderr, "FAIL: handshake message fragment 1 length = %zu, want %zu\n",
+                    CBS_len(&cbs), sizeof(dtls12_hs_msg_frag_1));
+                goto failure;
+        }
+        if (memcmp(CBS_data(&cbs), dtls12_hs_msg_frag_1, CBS_len(&cbs)) != 0) {
+                fprintf(stderr, "FAIL: got handshake message 1 fragment:\n");
+                hexdump(CBS_data(&cbs), CBS_len(&cbs));
+                fprintf(stderr, "want handshake message 1 fragment:\n");
+                hexdump(dtls12_hs_msg_frag_1, CBS_len(&cbs));
+        }
+
+        if (!dtls12_handshake_msg_fragment_next(hs_msg)) {
+                fprintf(stderr, "FAIL: failed to progress to next fragment\n");
+                goto failure;
+        }
+        if (!dtls12_handshake_msg_fragment_pending(hs_msg)) {
+                fprintf(stderr, "FAIL: handshake message should have pending fragments\n");
+                goto failure;
+        }
+
+        if (!dtls12_handshake_msg_fragment_build(hs_msg, 128, &cbs)) {
+                fprintf(stderr, "FAIL: failed to build handshake message fragment 2\n");
+                goto failure;
+        }
+        if (CBS_len(&cbs) != sizeof(dtls12_hs_msg_frag_2)) {
+                fprintf(stderr, "FAIL: handshake message fragment 2 length = %zu, want %zu\n",
+                    CBS_len(&cbs), sizeof(dtls12_hs_msg_frag_2));
+                goto failure;
+        }
+        if (memcmp(CBS_data(&cbs), dtls12_hs_msg_frag_2, CBS_len(&cbs)) != 0) {
+                fprintf(stderr, "FAIL: got handshake message 2 fragment:\n");
+                hexdump(CBS_data(&cbs), CBS_len(&cbs));
+                fprintf(stderr, "want handshake message 2 fragment:\n");
+                hexdump(dtls12_hs_msg_frag_2, CBS_len(&cbs));
+        }
+
+        if (!dtls12_handshake_msg_fragment_next(hs_msg)) {
+                fprintf(stderr, "FAIL: failed to progress to next fragment\n");
+                goto failure;
+        }
+        if (!dtls12_handshake_msg_fragment_pending(hs_msg)) {
+                fprintf(stderr, "FAIL: handshake message should have pending fragments\n");
+                goto failure;
+        }
+
+        if (!dtls12_handshake_msg_fragment_build(hs_msg, 128, &cbs)) {
+                fprintf(stderr, "FAIL: failed to build handshake message fragment 3\n");
+                goto failure;
+        }
+        if (CBS_len(&cbs) != sizeof(dtls12_hs_msg_frag_3)) {
+                fprintf(stderr, "FAIL: handshake message fragment 3 length = %zu, want %zu\n",
+                    CBS_len(&cbs), sizeof(dtls12_hs_msg_frag_3));
+                goto failure;
+        }
+        if (memcmp(CBS_data(&cbs), dtls12_hs_msg_frag_3, CBS_len(&cbs)) != 0) {
+                fprintf(stderr, "FAIL: got handshake message 3 fragment:\n");
+                hexdump(CBS_data(&cbs), CBS_len(&cbs));
+                fprintf(stderr, "want handshake message 3 fragment:\n");
+                hexdump(dtls12_hs_msg_frag_2, CBS_len(&cbs));
+        }
+
+        if (!dtls12_handshake_msg_fragment_next(hs_msg)) {
+                fprintf(stderr, "FAIL: failed to progress to next fragment\n");
+                goto failure;
+        }
+        if (dtls12_handshake_msg_fragment_pending(hs_msg)) {
+                fprintf(stderr, "FAIL: handshake message should not have pending fragments\n");
+                goto failure;
+        }
+        if (dtls12_handshake_msg_fragment_next(hs_msg)) {
+                fprintf(stderr, "FAIL: should have failed to progress to next fragment\n");
+                goto failure;
+        }
+
+        if (!dtls12_handshake_msg_fragment_reset(hs_msg)) {
+                fprintf(stderr, "FAIL: failed to reset handshake message fragments\n");
+                goto failure;
+        }
+        if (!dtls12_handshake_msg_fragment_pending(hs_msg)) {
+                fprintf(stderr, "FAIL: handshake message should have pending fragments after reset\n");
+                goto failure;
+        }
+
+        failed = 0;
+
+ failure:
+        dtls12_handshake_msg_free(hs_msg);
+
+        CBB_cleanup(&cbb);
+
+        return failed;
+}
+
+int
+main(int argc, char **argv)
+{
+        int failed = 0;
+
+        failed |= dtls_handshake_msg_test();
+
+        return failed;
+}