Provide a TLS record handling implementation.

This is a self-contained struct and set of functions that knows how to
decode and read a TLS record from data supplied via a read callback, and
send itself via a write callback.

This will soon be used to build the TLSv1.3 record layer handling code.

ok beck@ tb@

3 files changed, 220 insertions, 2 deletions

diff --git a/src/lib/libssl/Makefile b/src/lib/libssl/Makefile
index 9fc010d534..a5a1f2927f 100644
--- a/src/lib/libssl/Makefile
+++ b/src/lib/libssl/Makefile
@@ -1,4 +1,4 @@
-# $OpenBSD: Makefile,v 1.46 2019/01/18 03:41:30 beck Exp $
+# $OpenBSD: Makefile,v 1.47 2019/01/19 02:53:54 jsing Exp $
 
 .include <bsd.own.mk>
 .ifndef NOMAN
@@ -35,7 +35,7 @@ SRCS= \
         bio_ssl.c ssl_err.c ssl_methods.c \
         ssl_packet.c ssl_tlsext.c ssl_versions.c pqueue.c ssl_init.c \
         tls13_buffer.c tls13_handshake.c tls13_key_schedule.c \
-        ssl_sigalgs.c
+        tls13_record.c ssl_sigalgs.c
 SRCS+=  s3_cbc.c
 SRCS+=  bs_ber.c bs_cbb.c bs_cbs.c
 
diff --git a/src/lib/libssl/tls13_record.c b/src/lib/libssl/tls13_record.c
new file mode 100644
index 0000000000..857d3bee49
--- /dev/null
+++ b/src/lib/libssl/tls13_record.c
@@ -0,0 +1,160 @@
+/* $OpenBSD: tls13_record.c,v 1.1 2019/01/19 02:53:54 jsing Exp $ */
+/*
+ * Copyright (c) 2018, 2019 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 "ssl_locl.h"
+
+#include <openssl/curve25519.h>
+
+#include "tls13_internal.h"
+#include "tls13_record.h"
+
+struct tls13_record {
+        uint8_t content_type;
+        size_t rec_len;
+        uint8_t *data;
+        size_t data_len;
+        CBS cbs;
+
+        struct tls13_buffer *buf;
+};
+
+struct tls13_record *
+tls13_record_new(void)
+{
+        struct tls13_record *rec = NULL;
+
+        if ((rec = calloc(1, sizeof(struct tls13_record))) == NULL)
+                goto err;
+        if ((rec->buf = tls13_buffer_new(TLS13_RECORD_MAX_LEN)) == NULL)
+                goto err;
+
+        return rec;
+
+ err:
+        tls13_record_free(rec);
+
+        return NULL;
+}
+
+void
+tls13_record_free(struct tls13_record *rec)
+{
+        if (rec == NULL)
+                return;
+
+        tls13_buffer_free(rec->buf);
+
+        freezero(rec->data, rec->data_len);
+        freezero(rec, sizeof(struct tls13_record));
+}
+
+uint8_t
+tls13_record_content_type(struct tls13_record *rec)
+{
+        return rec->content_type;
+}
+
+int
+tls13_record_content(struct tls13_record *rec, CBS *cbs)
+{
+        CBS content;
+
+        tls13_record_data(rec, &content);
+
+        if (!CBS_skip(&content, TLS13_RECORD_HEADER_LEN))
+                return 0;
+
+        CBS_dup(&content, cbs);
+
+        return 1;
+}
+
+void
+tls13_record_data(struct tls13_record *rec, CBS *cbs)
+{
+        CBS_init(cbs, rec->data, rec->data_len);
+}
+
+void
+tls13_record_set_data(struct tls13_record *rec, uint8_t *data, size_t data_len)
+{
+        freezero(rec->data, rec->data_len);
+        rec->data = data;
+        rec->data_len = data_len;
+        CBS_init(&rec->cbs, rec->data, rec->data_len);
+}
+
+ssize_t
+tls13_record_recv(struct tls13_record *rec, tls13_read_cb wire_read,
+    void *wire_arg)
+{
+        uint16_t rec_len, rec_version;
+        uint8_t content_type;
+        CBS cbs;
+        int ret;
+
+        if (rec->data != NULL)
+                return TLS13_IO_FAILURE;
+
+        if (rec->content_type == 0) {
+                if ((ret = tls13_buffer_extend(rec->buf,
+                    TLS13_RECORD_HEADER_LEN, wire_read, wire_arg)) <= 0)
+                        return ret;
+
+                tls13_buffer_cbs(rec->buf, &cbs);
+
+                if (!CBS_get_u8(&cbs, &content_type))
+                        return TLS13_IO_FAILURE;
+                if (!CBS_get_u16(&cbs, &rec_version))
+                        return TLS13_IO_FAILURE;
+                if (!CBS_get_u16(&cbs, &rec_len))
+                        return TLS13_IO_FAILURE;
+
+                rec->content_type = content_type;
+                rec->rec_len = rec_len;
+        }
+
+        if ((ret = tls13_buffer_extend(rec->buf,
+            TLS13_RECORD_HEADER_LEN + rec->rec_len, wire_read, wire_arg)) <= 0)
+                return ret;
+
+        if (!tls13_buffer_finish(rec->buf, &rec->data, &rec->data_len))
+                return TLS13_IO_FAILURE;
+
+        return rec->data_len;
+}
+
+ssize_t
+tls13_record_send(struct tls13_record *rec, tls13_write_cb wire_write,
+    void *wire_arg)
+{
+        ssize_t ret;
+
+        if (rec->data == NULL)
+                return TLS13_IO_FAILURE;
+
+        while (CBS_len(&rec->cbs) > 0) {
+                if ((ret = wire_write(CBS_data(&rec->cbs),
+                    CBS_len(&rec->cbs), wire_arg)) <= 0)
+                        return ret;
+
+                if (!CBS_skip(&rec->cbs, ret))
+                        return TLS13_IO_FAILURE;
+        }
+
+        return rec->data_len;
+}
diff --git a/src/lib/libssl/tls13_record.h b/src/lib/libssl/tls13_record.h
new file mode 100644
index 0000000000..ca7a63f99c
--- /dev/null
+++ b/src/lib/libssl/tls13_record.h
@@ -0,0 +1,58 @@
+/* $OpenBSD: tls13_record.h,v 1.1 2019/01/19 02:53:54 jsing Exp $ */
+/*
+ * Copyright (c) 2019 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.
+ */
+
+#ifndef HEADER_TLS13_RECORD_H
+#define HEADER_TLS13_RECORD_H
+
+#include "bytestring.h"
+#include "tls13_internal.h"
+
+__BEGIN_HIDDEN_DECLS
+
+/*
+ * TLSv1.3 - RFC 8446 section 5.
+ *
+ * The maximum plaintext is 2^14, however for inner plaintext an additional
+ * byte is allowed for the content type. A maximum AEAD overhead of 255-bytes
+ * is permitted, along with a 5-byte header, giving a maximum size of
+ * 5 + 2^14 + 1 + 255 = 16,645-bytes.
+ */
+#define TLS13_RECORD_HEADER_LEN                 5
+#define TLS13_RECORD_MAX_AEAD_OVERHEAD          255
+#define TLS13_RECORD_MAX_PLAINTEXT_LEN          16384
+#define TLS13_RECORD_MAX_INNER_PLAINTEXT_LEN \
+        (TLS13_RECORD_MAX_PLAINTEXT_LEN + 1)
+#define TLS13_RECORD_MAX_CIPHERTEXT \
+        (TLS13_RECORD_MAX_INNER_PLAINTEXT_LEN + TLS13_RECORD_MAX_AEAD_OVERHEAD)
+#define TLS13_RECORD_MAX_LEN \
+        (TLS13_RECORD_HEADER_LEN + TLS13_RECORD_MAX_CIPHERTEXT)
+
+struct tls13_record *tls13_record_new(void);
+void tls13_record_free(struct tls13_record *_rec);
+uint8_t tls13_record_content_type(struct tls13_record *_rec);
+int tls13_record_content(struct tls13_record *_rec, CBS *_cbs);
+void tls13_record_data(struct tls13_record *_rec, CBS *_cbs);
+void tls13_record_set_data(struct tls13_record *_rec, uint8_t *_data,
+    size_t _data_len);
+ssize_t tls13_record_recv(struct tls13_record *_rec, tls13_read_cb _wire_read,
+    void *_wire_arg);
+ssize_t tls13_record_send(struct tls13_record *_rec, tls13_write_cb _wire_write,
+    void *_wire_arg);
+
+__END_HIDDEN_DECLS
+
+#endif