diff --git a/include/openssl/bytestring.h b/include/openssl/bytestring.h
index 4fceeaa..f6db950 100644
--- a/include/openssl/bytestring.h
+++ b/include/openssl/bytestring.h
@@ -99,6 +99,10 @@
  * |cbs|. It returns one on success and zero on error. */
 OPENSSL_EXPORT int CBS_get_bytes(CBS *cbs, CBS *out, size_t len);
 
+/* CBS_copy_bytes copies the next |len| bytes from |cbs| to |out| and advances
+ * |cbs|. It returns one on success and zero on error. */
+OPENSSL_EXPORT int CBS_copy_bytes(CBS *cbs, uint8_t *out, size_t len);
+
 /* CBS_get_u8_length_prefixed sets |*out| to the contents of an 8-bit,
  * length-prefixed value from |cbs| and advances |cbs| over it. It returns one
  * on success and zero on error. */
diff --git a/include/openssl/ssl.h b/include/openssl/ssl.h
index d6e352e..50fe9bd 100644
--- a/include/openssl/ssl.h
+++ b/include/openssl/ssl.h
@@ -292,6 +292,7 @@
 
 /* Protocol versions. */
 
+#define DTLS1_VERSION_MAJOR 0xfe
 #define SSL3_VERSION_MAJOR 0x03
 
 #define SSL3_VERSION 0x0300
@@ -1724,7 +1725,6 @@
   int shutdown; /* we have shut things down, 0x01 sent, 0x02
                  * for received */
   int state;    /* where we are */
-  int rstate;   /* where we are when reading */
 
   BUF_MEM *init_buf; /* buffer used during init */
   uint8_t *init_msg; /* pointer to handshake message body, set by
@@ -1732,10 +1732,6 @@
   int init_num;      /* amount read/written */
   int init_off;      /* amount read/written */
 
-  /* used internally to point at a raw packet */
-  uint8_t *packet;
-  unsigned int packet_length;
-
   struct ssl3_state_st *s3;  /* SSLv3 variables */
   struct dtls1_state_st *d1; /* DTLSv1 variables */
 
@@ -1910,12 +1906,6 @@
  * for the peer, but |SSL_read| will require the handshake to be completed. */
 OPENSSL_EXPORT int SSL_in_false_start(const SSL *s);
 
-/* The following 2 states are kept in ssl->rstate when reads fail,
- * you should not need these */
-#define SSL_ST_READ_HEADER 0xF0
-#define SSL_ST_READ_BODY 0xF1
-#define SSL_ST_READ_DONE 0xF2
-
 /* Obtain latest Finished message
  *   -- that we sent (SSL_get_finished)
  *   -- that we expected from peer (SSL_get_peer_finished).
@@ -2158,9 +2148,7 @@
 OPENSSL_EXPORT void SSL_load_error_strings(void);
 
 OPENSSL_EXPORT const char *SSL_state_string(const SSL *s);
-OPENSSL_EXPORT const char *SSL_rstate_string(const SSL *s);
 OPENSSL_EXPORT const char *SSL_state_string_long(const SSL *s);
-OPENSSL_EXPORT const char *SSL_rstate_string_long(const SSL *s);
 OPENSSL_EXPORT long SSL_SESSION_get_time(const SSL_SESSION *s);
 OPENSSL_EXPORT long SSL_SESSION_set_time(SSL_SESSION *s, long t);
 OPENSSL_EXPORT long SSL_SESSION_get_timeout(const SSL_SESSION *s);
diff --git a/include/openssl/ssl3.h b/include/openssl/ssl3.h
index 7ff8dbd..e04412f 100644
--- a/include/openssl/ssl3.h
+++ b/include/openssl/ssl3.h
@@ -272,10 +272,6 @@
 #define SSL3_MD_CLIENT_FINISHED_CONST "\x43\x4C\x4E\x54"
 #define SSL3_MD_SERVER_FINISHED_CONST "\x53\x52\x56\x52"
 
-#define SSL3_VERSION 0x0300
-#define SSL3_VERSION_MAJOR 0x03
-#define SSL3_VERSION_MINOR 0x00
-
 #define SSL3_RT_CHANGE_CIPHER_SPEC 20
 #define SSL3_RT_ALERT 21
 #define SSL3_RT_HANDSHAKE 22
@@ -311,16 +307,17 @@
   /* data is a non-owning pointer to the record contents. The total length of
    * the buffer is |off| + |length|. */
   uint8_t *data;
-  /* epoch, in DTLS, is the epoch number of the record. */
-  uint16_t epoch;
 } SSL3_RECORD;
 
 typedef struct ssl3_buffer_st {
-  uint8_t *buf;       /* at least SSL3_RT_MAX_PACKET_SIZE bytes, see
-                         ssl3_setup_buffers() */
-  size_t len;         /* buffer size */
-  int offset;         /* where to 'copy from' */
-  int left;           /* how many bytes left */
+  /* buf is the memory allocated for this buffer. */
+  uint8_t *buf;
+  /* offset is the offset into |buf| which the buffer contents start at. */
+  uint16_t offset;
+  /* len is the length of the buffer contents from |buf| + |offset|. */
+  uint16_t len;
+  /* cap is how much memory beyond |buf| + |offset| is available. */
+  uint16_t cap;
 } SSL3_BUFFER;
 
 #define SSL3_CT_RSA_SIGN 1
@@ -352,9 +349,6 @@
   /* flags for countermeasure against known-IV weakness */
   int need_record_splitting;
 
-  /* The value of 'extra' when the buffers were initialized */
-  int init_extra;
-
   /* have_version is true if the connection's final version is known. Otherwise
    * the version has not been negotiated yet. */
   char have_version;
@@ -363,8 +357,10 @@
    * completed. */
   char initial_handshake_complete;
 
-  SSL3_BUFFER rbuf; /* read IO goes into here */
-  SSL3_BUFFER wbuf; /* write IO goes into here */
+  /* read_buffer holds data from the transport to be processed. */
+  SSL3_BUFFER read_buffer;
+  /* write_buffer holds data to be written to the transport. */
+  SSL3_BUFFER write_buffer;
 
   SSL3_RECORD rrec; /* each decoded record goes in here */