Move SSL3_RECORD oriented functions into ssl3_record.c

Reviewed-by: Richard Levitte <levitte@openssl.org>

5 files changed, 729 insertions, 715 deletions

diff --git a/ssl/d1_pkt.c b/ssl/d1_pkt.c
index fbfc7232df..6be5dae96c 100644
--- a/ssl/d1_pkt.c
+++ b/ssl/d1_pkt.c
@@ -183,13 +183,6 @@ static int satsub64be(const unsigned char *v1, const unsigned char *v2)
 
 static int have_handshake_fragment(SSL *s, int type, unsigned char *buf,
                                    int len, int peek);
-static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap);
-static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap);
-static DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr,
-                                      unsigned int *is_next_epoch);
-static int dtls1_buffer_record(SSL *s, record_pqueue *q,
-                               unsigned char *priority);
-static int dtls1_process_record(SSL *s);
 
 /* copy buffered record into SSL structure */
 static int dtls1_copy_record(SSL *s, pitem *item)
@@ -213,7 +206,7 @@ static int dtls1_copy_record(SSL *s, pitem *item)
     return (1);
 }
 
-static int
+int
 dtls1_buffer_record(SSL *s, record_pqueue *queue, unsigned char *priority)
 {
     DTLS1_RECORD_DATA *rdata;
@@ -281,7 +274,7 @@ dtls1_buffer_record(SSL *s, record_pqueue *queue, unsigned char *priority)
     return (1);
 }
 
-static int dtls1_retrieve_buffered_record(SSL *s, record_pqueue *queue)
+int dtls1_retrieve_buffered_record(SSL *s, record_pqueue *queue)
 {
     pitem *item;
 
@@ -306,15 +299,8 @@ static int dtls1_retrieve_buffered_record(SSL *s, record_pqueue *queue)
                    dtls1_retrieve_buffered_record((s), \
                    &((s)->d1->unprocessed_rcds))
 
-/*
- * retrieve a buffered record that belongs to the current epoch, ie,
- * processed
- */
-#define dtls1_get_processed_record(s) \
-                   dtls1_retrieve_buffered_record((s), \
-                   &((s)->d1->processed_rcds))
 
-static int dtls1_process_buffered_records(SSL *s)
+int dtls1_process_buffered_records(SSL *s)
 {
     pitem *item;
 
@@ -345,351 +331,6 @@ static int dtls1_process_buffered_records(SSL *s)
     return (1);
 }
 
-static int dtls1_process_record(SSL *s)
-{
-    int i, al;
-    int enc_err;
-    SSL_SESSION *sess;
-    SSL3_RECORD *rr;
-    unsigned int mac_size;
-    unsigned char md[EVP_MAX_MD_SIZE];
-
-    rr = RECORD_LAYER_get_rrec(&s->rlayer);
-    sess = s->session;
-
-    /*
-     * At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
-     * and we have that many bytes in s->packet
-     */
-    rr->input = &(s->packet[DTLS1_RT_HEADER_LENGTH]);
-
-    /*
-     * ok, we can now read from 's->packet' data into 'rr' rr->input points
-     * at rr->length bytes, which need to be copied into rr->data by either
-     * the decryption or by the decompression When the data is 'copied' into
-     * the rr->data buffer, rr->input will be pointed at the new buffer
-     */
-
-    /*
-     * We now have - encrypted [ MAC [ compressed [ plain ] ] ] rr->length
-     * bytes of encrypted compressed stuff.
-     */
-
-    /* check is not needed I believe */
-    if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH) {
-        al = SSL_AD_RECORD_OVERFLOW;
-        SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
-        goto f_err;
-    }
-
-    /* decrypt in place in 'rr->input' */
-    rr->data = rr->input;
-    rr->orig_len = rr->length;
-
-    enc_err = s->method->ssl3_enc->enc(s, 0);
-    /*-
-     * enc_err is:
-     *    0: (in non-constant time) if the record is publically invalid.
-     *    1: if the padding is valid
-     *   -1: if the padding is invalid
-     */
-    if (enc_err == 0) {
-        /* For DTLS we simply ignore bad packets. */
-        rr->length = 0;
-        s->packet_length = 0;
-        goto err;
-    }
-#ifdef TLS_DEBUG
-    printf("dec %d\n", rr->length);
-    {
-        unsigned int z;
-        for (z = 0; z < rr->length; z++)
-            printf("%02X%c", rr->data[z], ((z + 1) % 16) ? ' ' : '\n');
-    }
-    printf("\n");
-#endif
-
-    /* r->length is now the compressed data plus mac */
-    if ((sess != NULL) &&
-        (s->enc_read_ctx != NULL) && (EVP_MD_CTX_md(s->read_hash) != NULL)) {
-        /* s->read_hash != NULL => mac_size != -1 */
-        unsigned char *mac = NULL;
-        unsigned char mac_tmp[EVP_MAX_MD_SIZE];
-        mac_size = EVP_MD_CTX_size(s->read_hash);
-        OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
-
-        /*
-         * orig_len is the length of the record before any padding was
-         * removed. This is public information, as is the MAC in use,
-         * therefore we can safely process the record in a different amount
-         * of time if it's too short to possibly contain a MAC.
-         */
-        if (rr->orig_len < mac_size ||
-            /* CBC records must have a padding length byte too. */
-            (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
-             rr->orig_len < mac_size + 1)) {
-            al = SSL_AD_DECODE_ERROR;
-            SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_LENGTH_TOO_SHORT);
-            goto f_err;
-        }
-
-        if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE) {
-            /*
-             * We update the length so that the TLS header bytes can be
-             * constructed correctly but we need to extract the MAC in
-             * constant time from within the record, without leaking the
-             * contents of the padding bytes.
-             */
-            mac = mac_tmp;
-            ssl3_cbc_copy_mac(mac_tmp, rr, mac_size);
-            rr->length -= mac_size;
-        } else {
-            /*
-             * In this case there's no padding, so |rec->orig_len| equals
-             * |rec->length| and we checked that there's enough bytes for
-             * |mac_size| above.
-             */
-            rr->length -= mac_size;
-            mac = &rr->data[rr->length];
-        }
-
-        i = s->method->ssl3_enc->mac(s, md, 0 /* not send */ );
-        if (i < 0 || mac == NULL
-            || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
-            enc_err = -1;
-        if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + mac_size)
-            enc_err = -1;
-    }
-
-    if (enc_err < 0) {
-        /* decryption failed, silently discard message */
-        rr->length = 0;
-        s->packet_length = 0;
-        goto err;
-    }
-
-    /* r->length is now just compressed */
-    if (s->expand != NULL) {
-        if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH) {
-            al = SSL_AD_RECORD_OVERFLOW;
-            SSLerr(SSL_F_DTLS1_PROCESS_RECORD,
-                   SSL_R_COMPRESSED_LENGTH_TOO_LONG);
-            goto f_err;
-        }
-        if (!ssl3_do_uncompress(s)) {
-            al = SSL_AD_DECOMPRESSION_FAILURE;
-            SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_BAD_DECOMPRESSION);
-            goto f_err;
-        }
-    }
-
-    if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH) {
-        al = SSL_AD_RECORD_OVERFLOW;
-        SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_DATA_LENGTH_TOO_LONG);
-        goto f_err;
-    }
-
-    rr->off = 0;
-    /*-
-     * So at this point the following is true
-     * ssl->s3->rrec.type   is the type of record
-     * ssl->s3->rrec.length == number of bytes in record
-     * ssl->s3->rrec.off    == offset to first valid byte
-     * ssl->s3->rrec.data   == where to take bytes from, increment
-     *                         after use :-).
-     */
-
-    /* we have pulled in a full packet so zero things */
-    s->packet_length = 0;
-    return (1);
-
- f_err:
-    ssl3_send_alert(s, SSL3_AL_FATAL, al);
- err:
-    return (0);
-}
-
-/*-
- * Call this to get a new input record.
- * It will return <= 0 if more data is needed, normally due to an error
- * or non-blocking IO.
- * When it finishes, one packet has been decoded and can be found in
- * ssl->s3->rrec.type    - is the type of record
- * ssl->s3->rrec.data,   - data
- * ssl->s3->rrec.length, - number of bytes
- */
-/* used only by dtls1_read_bytes */
-int dtls1_get_record(SSL *s)
-{
-    int ssl_major, ssl_minor;
-    int i, n;
-    SSL3_RECORD *rr;
-    unsigned char *p = NULL;
-    unsigned short version;
-    DTLS1_BITMAP *bitmap;
-    unsigned int is_next_epoch;
-
-    rr = RECORD_LAYER_get_rrec(&s->rlayer);
-
-    /*
-     * The epoch may have changed.  If so, process all the pending records.
-     * This is a non-blocking operation.
-     */
-    if (dtls1_process_buffered_records(s) < 0)
-        return -1;
-
-    /* if we're renegotiating, then there may be buffered records */
-    if (dtls1_get_processed_record(s))
-        return 1;
-
-    /* get something from the wire */
- again:
-    /* check if we have the header */
-    if ((s->rstate != SSL_ST_READ_BODY) ||
-        (s->packet_length < DTLS1_RT_HEADER_LENGTH)) {
-        n = ssl3_read_n(s, DTLS1_RT_HEADER_LENGTH,
-            SSL3_BUFFER_get_len(RECORD_LAYER_get_rbuf(&s->rlayer)), 0);
-        /* read timeout is handled by dtls1_read_bytes */
-        if (n <= 0)
-            return (n);         /* error or non-blocking */
-
-        /* this packet contained a partial record, dump it */
-        if (s->packet_length != DTLS1_RT_HEADER_LENGTH) {
-            s->packet_length = 0;
-            goto again;
-        }
-
-        s->rstate = SSL_ST_READ_BODY;
-
-        p = s->packet;
-
-        if (s->msg_callback)
-            s->msg_callback(0, 0, SSL3_RT_HEADER, p, DTLS1_RT_HEADER_LENGTH,
-                            s, s->msg_callback_arg);
-
-        /* Pull apart the header into the DTLS1_RECORD */
-        rr->type = *(p++);
-        ssl_major = *(p++);
-        ssl_minor = *(p++);
-        version = (ssl_major << 8) | ssl_minor;
-
-        /* sequence number is 64 bits, with top 2 bytes = epoch */
-        n2s(p, rr->epoch);
-
-        memcpy(&(s->s3->read_sequence[2]), p, 6);
-        p += 6;
-
-        n2s(p, rr->length);
-
-        /* Lets check version */
-        if (!s->first_packet) {
-            if (version != s->version) {
-                /* unexpected version, silently discard */
-                rr->length = 0;
-                s->packet_length = 0;
-                goto again;
-            }
-        }
-
-        if ((version & 0xff00) != (s->version & 0xff00)) {
-            /* wrong version, silently discard record */
-            rr->length = 0;
-            s->packet_length = 0;
-            goto again;
-        }
-
-        if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH) {
-            /* record too long, silently discard it */
-            rr->length = 0;
-            s->packet_length = 0;
-            goto again;
-        }
-
-        /* now s->rstate == SSL_ST_READ_BODY */
-    }
-
-    /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
-
-    if (rr->length > s->packet_length - DTLS1_RT_HEADER_LENGTH) {
-        /* now s->packet_length == DTLS1_RT_HEADER_LENGTH */
-        i = rr->length;
-        n = ssl3_read_n(s, i, i, 1);
-        /* this packet contained a partial record, dump it */
-        if (n != i) {
-            rr->length = 0;
-            s->packet_length = 0;
-            goto again;
-        }
-
-        /*
-         * now n == rr->length, and s->packet_length ==
-         * DTLS1_RT_HEADER_LENGTH + rr->length
-         */
-    }
-    s->rstate = SSL_ST_READ_HEADER; /* set state for later operations */
-
-    /* match epochs.  NULL means the packet is dropped on the floor */
-    bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch);
-    if (bitmap == NULL) {
-        rr->length = 0;
-        s->packet_length = 0;   /* dump this record */
-        goto again;             /* get another record */
-    }
-#ifndef OPENSSL_NO_SCTP
-    /* Only do replay check if no SCTP bio */
-    if (!BIO_dgram_is_sctp(SSL_get_rbio(s))) {
-#endif
-        /*
-         * Check whether this is a repeat, or aged record. Don't check if
-         * we're listening and this message is a ClientHello. They can look
-         * as if they're replayed, since they arrive from different
-         * connections and would be dropped unnecessarily.
-         */
-        if (!(s->d1->listen && rr->type == SSL3_RT_HANDSHAKE &&
-              s->packet_length > DTLS1_RT_HEADER_LENGTH &&
-              s->packet[DTLS1_RT_HEADER_LENGTH] == SSL3_MT_CLIENT_HELLO) &&
-            !dtls1_record_replay_check(s, bitmap)) {
-            rr->length = 0;
-            s->packet_length = 0; /* dump this record */
-            goto again;         /* get another record */
-        }
-#ifndef OPENSSL_NO_SCTP
-    }
-#endif
-
-    /* just read a 0 length packet */
-    if (rr->length == 0)
-        goto again;
-
-    /*
-     * If this record is from the next epoch (either HM or ALERT), and a
-     * handshake is currently in progress, buffer it since it cannot be
-     * processed at this time. However, do not buffer anything while
-     * listening.
-     */
-    if (is_next_epoch) {
-        if ((SSL_in_init(s) || s->in_handshake) && !s->d1->listen) {
-            if (dtls1_buffer_record
-                (s, &(s->d1->unprocessed_rcds), rr->seq_num) < 0)
-                return -1;
-            /* Mark receipt of record. */
-            dtls1_record_bitmap_update(s, bitmap);
-        }
-        rr->length = 0;
-        s->packet_length = 0;
-        goto again;
-    }
-
-    if (!dtls1_process_record(s)) {
-        rr->length = 0;
-        s->packet_length = 0;   /* dump this record */
-        goto again;             /* get another record */
-    }
-    dtls1_record_bitmap_update(s, bitmap); /* Mark receipt of record. */
-
-    return (1);
-
-}
 
 /*-
  * Return up to 'len' payload bytes received in 'type' records.
@@ -1623,7 +1264,7 @@ int do_dtls1_write(SSL *s, int type, const unsigned char *buf,
     return -1;
 }
 
-static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap)
+int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap)
 {
     int cmp;
     unsigned int shift;
@@ -1644,7 +1285,7 @@ static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap)
     return 1;
 }
 
-static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap)
+void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap)
 {
     int cmp;
     unsigned int shift;
@@ -1714,7 +1355,7 @@ int dtls1_dispatch_alert(SSL *s)
     return (i);
 }
 
-static DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr,
+DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr,
                                       unsigned int *is_next_epoch)
 {
 
diff --git a/ssl/record/ssl3_record.c b/ssl/record/ssl3_record.c
index f78f2fef4e..412d8e4319 100644
--- a/ssl/record/ssl3_record.c
+++ b/ssl/record/ssl3_record.c
@@ -136,3 +136,707 @@ void SSL3_RECORD_set_seq_num(SSL3_RECORD *r, const unsigned char *seq_num)
 {
     memcpy(r->seq_num, seq_num, 8);
 }
+
+/*
+ * MAX_EMPTY_RECORDS defines the number of consecutive, empty records that
+ * will be processed per call to ssl3_get_record. Without this limit an
+ * attacker could send empty records at a faster rate than we can process and
+ * cause ssl3_get_record to loop forever.
+ */
+#define MAX_EMPTY_RECORDS 32
+
+/*-
+ * Call this to get a new input record.
+ * It will return <= 0 if more data is needed, normally due to an error
+ * or non-blocking IO.
+ * When it finishes, one packet has been decoded and can be found in
+ * ssl->s3->rrec.type    - is the type of record
+ * ssl->s3->rrec.data,   - data
+ * ssl->s3->rrec.length, - number of bytes
+ */
+/* used only by ssl3_read_bytes */
+int ssl3_get_record(SSL *s)
+{
+    int ssl_major, ssl_minor, al;
+    int enc_err, n, i, ret = -1;
+    SSL3_RECORD *rr;
+    SSL_SESSION *sess;
+    unsigned char *p;
+    unsigned char md[EVP_MAX_MD_SIZE];
+    short version;
+    unsigned mac_size;
+    size_t extra;
+    unsigned empty_record_count = 0;
+
+    rr = RECORD_LAYER_get_rrec(&s->rlayer);
+    sess = s->session;
+
+    if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
+        extra = SSL3_RT_MAX_EXTRA;
+    else
+        extra = 0;
+    if (extra && !s->s3->init_extra) {
+        /*
+         * An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER set after
+         * ssl3_setup_buffers() was done
+         */
+        SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
+        return -1;
+    }
+
+ again:
+    /* check if we have the header */
+    if ((s->rstate != SSL_ST_READ_BODY) ||
+        (s->packet_length < SSL3_RT_HEADER_LENGTH)) {
+        n = ssl3_read_n(s, SSL3_RT_HEADER_LENGTH,
+            SSL3_BUFFER_get_len(RECORD_LAYER_get_rbuf(&s->rlayer)), 0);
+        if (n <= 0)
+            return (n);         /* error or non-blocking */
+        s->rstate = SSL_ST_READ_BODY;
+
+        p = s->packet;
+        if (s->msg_callback)
+            s->msg_callback(0, 0, SSL3_RT_HEADER, p, 5, s,
+                            s->msg_callback_arg);
+
+        /* Pull apart the header into the SSL3_RECORD */
+        rr->type = *(p++);
+        ssl_major = *(p++);
+        ssl_minor = *(p++);
+        version = (ssl_major << 8) | ssl_minor;
+        n2s(p, rr->length);
+
+        /* Lets check version */
+        if (!s->first_packet) {
+            if (version != s->version) {
+                SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_WRONG_VERSION_NUMBER);
+                if ((s->version & 0xFF00) == (version & 0xFF00)
+                    && !s->enc_write_ctx && !s->write_hash)
+                    /*
+                     * Send back error using their minor version number :-)
+                     */
+                    s->version = (unsigned short)version;
+                al = SSL_AD_PROTOCOL_VERSION;
+                goto f_err;
+            }
+        }
+
+        if ((version >> 8) != SSL3_VERSION_MAJOR) {
+            SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_WRONG_VERSION_NUMBER);
+            goto err;
+        }
+
+        if (rr->length >
+                SSL3_BUFFER_get_len(RECORD_LAYER_get_rbuf(&s->rlayer))
+                - SSL3_RT_HEADER_LENGTH) {
+            al = SSL_AD_RECORD_OVERFLOW;
+            SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_PACKET_LENGTH_TOO_LONG);
+            goto f_err;
+        }
+
+        /* now s->rstate == SSL_ST_READ_BODY */
+    }
+
+    /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
+
+    if (rr->length > s->packet_length - SSL3_RT_HEADER_LENGTH) {
+        /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
+        i = rr->length;
+        n = ssl3_read_n(s, i, i, 1);
+        if (n <= 0)
+            return (n);         /* error or non-blocking io */
+        /*
+         * now n == rr->length, and s->packet_length == SSL3_RT_HEADER_LENGTH
+         * + rr->length
+         */
+    }
+
+    s->rstate = SSL_ST_READ_HEADER; /* set state for later operations */
+
+    /*
+     * At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
+     * and we have that many bytes in s->packet
+     */
+    rr->input = &(s->packet[SSL3_RT_HEADER_LENGTH]);
+
+    /*
+     * ok, we can now read from 's->packet' data into 'rr' rr->input points
+     * at rr->length bytes, which need to be copied into rr->data by either
+     * the decryption or by the decompression When the data is 'copied' into
+     * the rr->data buffer, rr->input will be pointed at the new buffer
+     */
+
+    /*
+     * We now have - encrypted [ MAC [ compressed [ plain ] ] ] rr->length
+     * bytes of encrypted compressed stuff.
+     */
+
+    /* check is not needed I believe */
+    if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH + extra) {
+        al = SSL_AD_RECORD_OVERFLOW;
+        SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
+        goto f_err;
+    }
+
+    /* decrypt in place in 'rr->input' */
+    rr->data = rr->input;
+    rr->orig_len = rr->length;
+    /*
+     * If in encrypt-then-mac mode calculate mac from encrypted record. All
+     * the details below are public so no timing details can leak.
+     */
+    if (SSL_USE_ETM(s) && s->read_hash) {
+        unsigned char *mac;
+        mac_size = EVP_MD_CTX_size(s->read_hash);
+        OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
+        if (rr->length < mac_size) {
+            al = SSL_AD_DECODE_ERROR;
+            SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_LENGTH_TOO_SHORT);
+            goto f_err;
+        }
+        rr->length -= mac_size;
+        mac = rr->data + rr->length;
+        i = s->method->ssl3_enc->mac(s, md, 0 /* not send */ );
+        if (i < 0 || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0) {
+            al = SSL_AD_BAD_RECORD_MAC;
+            SSLerr(SSL_F_SSL3_GET_RECORD,
+                   SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
+            goto f_err;
+        }
+    }
+
+    enc_err = s->method->ssl3_enc->enc(s, 0);
+    /*-
+     * enc_err is:
+     *    0: (in non-constant time) if the record is publically invalid.
+     *    1: if the padding is valid
+     *    -1: if the padding is invalid
+     */
+    if (enc_err == 0) {
+        al = SSL_AD_DECRYPTION_FAILED;
+        SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
+        goto f_err;
+    }
+#ifdef TLS_DEBUG
+    printf("dec %d\n", rr->length);
+    {
+        unsigned int z;
+        for (z = 0; z < rr->length; z++)
+            printf("%02X%c", rr->data[z], ((z + 1) % 16) ? ' ' : '\n');
+    }
+    printf("\n");
+#endif
+
+    /* r->length is now the compressed data plus mac */
+    if ((sess != NULL) &&
+        (s->enc_read_ctx != NULL) &&
+        (EVP_MD_CTX_md(s->read_hash) != NULL) && !SSL_USE_ETM(s)) {
+        /* s->read_hash != NULL => mac_size != -1 */
+        unsigned char *mac = NULL;
+        unsigned char mac_tmp[EVP_MAX_MD_SIZE];
+        mac_size = EVP_MD_CTX_size(s->read_hash);
+        OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
+
+        /*
+         * orig_len is the length of the record before any padding was
+         * removed. This is public information, as is the MAC in use,
+         * therefore we can safely process the record in a different amount
+         * of time if it's too short to possibly contain a MAC.
+         */
+        if (rr->orig_len < mac_size ||
+            /* CBC records must have a padding length byte too. */
+            (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
+             rr->orig_len < mac_size + 1)) {
+            al = SSL_AD_DECODE_ERROR;
+            SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_LENGTH_TOO_SHORT);
+            goto f_err;
+        }
+
+        if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE) {
+            /*
+             * We update the length so that the TLS header bytes can be
+             * constructed correctly but we need to extract the MAC in
+             * constant time from within the record, without leaking the
+             * contents of the padding bytes.
+             */
+            mac = mac_tmp;
+            ssl3_cbc_copy_mac(mac_tmp, rr, mac_size);
+            rr->length -= mac_size;
+        } else {
+            /*
+             * In this case there's no padding, so |rec->orig_len| equals
+             * |rec->length| and we checked that there's enough bytes for
+             * |mac_size| above.
+             */
+            rr->length -= mac_size;
+            mac = &rr->data[rr->length];
+        }
+
+        i = s->method->ssl3_enc->mac(s, md, 0 /* not send */ );
+        if (i < 0 || mac == NULL
+            || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
+            enc_err = -1;
+        if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + extra + mac_size)
+            enc_err = -1;
+    }
+
+    if (enc_err < 0) {
+        /*
+         * A separate 'decryption_failed' alert was introduced with TLS 1.0,
+         * SSL 3.0 only has 'bad_record_mac'.  But unless a decryption
+         * failure is directly visible from the ciphertext anyway, we should
+         * not reveal which kind of error occurred -- this might become
+         * visible to an attacker (e.g. via a logfile)
+         */
+        al = SSL_AD_BAD_RECORD_MAC;
+        SSLerr(SSL_F_SSL3_GET_RECORD,
+               SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
+        goto f_err;
+    }
+
+    /* r->length is now just compressed */
+    if (s->expand != NULL) {
+        if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + extra) {
+            al = SSL_AD_RECORD_OVERFLOW;
+            SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_COMPRESSED_LENGTH_TOO_LONG);
+            goto f_err;
+        }
+        if (!ssl3_do_uncompress(s)) {
+            al = SSL_AD_DECOMPRESSION_FAILURE;
+            SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_BAD_DECOMPRESSION);
+            goto f_err;
+        }
+    }
+
+    if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH + extra) {
+        al = SSL_AD_RECORD_OVERFLOW;
+        SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_DATA_LENGTH_TOO_LONG);
+        goto f_err;
+    }
+
+    rr->off = 0;
+    /*-
+     * So at this point the following is true
+     * ssl->s3->rrec.type   is the type of record
+     * ssl->s3->rrec.length == number of bytes in record
+     * ssl->s3->rrec.off    == offset to first valid byte
+     * ssl->s3->rrec.data   == where to take bytes from, increment
+     *                         after use :-).
+     */
+
+    /* we have pulled in a full packet so zero things */
+    s->packet_length = 0;
+
+    /* just read a 0 length packet */
+    if (rr->length == 0) {
+        empty_record_count++;
+        if (empty_record_count > MAX_EMPTY_RECORDS) {
+            al = SSL_AD_UNEXPECTED_MESSAGE;
+            SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_RECORD_TOO_SMALL);
+            goto f_err;
+        }
+        goto again;
+    }
+
+    return (1);
+
+ f_err:
+    ssl3_send_alert(s, SSL3_AL_FATAL, al);
+ err:
+    return (ret);
+}
+
+int ssl3_do_uncompress(SSL *ssl)
+{
+#ifndef OPENSSL_NO_COMP
+    int i;
+    SSL3_RECORD *rr;
+
+    rr = RECORD_LAYER_get_rrec(&ssl->rlayer);
+    i = COMP_expand_block(ssl->expand, rr->comp,
+                          SSL3_RT_MAX_PLAIN_LENGTH, rr->data,
+                          (int)rr->length);
+    if (i < 0)
+        return (0);
+    else
+        rr->length = i;
+    rr->data = rr->comp;
+#endif
+    return (1);
+}
+
+int ssl3_do_compress(SSL *ssl)
+{
+#ifndef OPENSSL_NO_COMP
+    int i;
+    SSL3_RECORD *wr;
+
+    wr = RECORD_LAYER_get_wrec(&ssl->rlayer);
+    i = COMP_compress_block(ssl->compress, wr->data,
+                            SSL3_RT_MAX_COMPRESSED_LENGTH,
+                            wr->input, (int)wr->length);
+    if (i < 0)
+        return (0);
+    else
+        wr->length = i;
+
+    wr->input = wr->data;
+#endif
+    return (1);
+}
+
+int dtls1_process_record(SSL *s)
+{
+    int i, al;
+    int enc_err;
+    SSL_SESSION *sess;
+    SSL3_RECORD *rr;
+    unsigned int mac_size;
+    unsigned char md[EVP_MAX_MD_SIZE];
+
+    rr = RECORD_LAYER_get_rrec(&s->rlayer);
+    sess = s->session;
+
+    /*
+     * At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
+     * and we have that many bytes in s->packet
+     */
+    rr->input = &(s->packet[DTLS1_RT_HEADER_LENGTH]);
+
+    /*
+     * ok, we can now read from 's->packet' data into 'rr' rr->input points
+     * at rr->length bytes, which need to be copied into rr->data by either
+     * the decryption or by the decompression When the data is 'copied' into
+     * the rr->data buffer, rr->input will be pointed at the new buffer
+     */
+
+    /*
+     * We now have - encrypted [ MAC [ compressed [ plain ] ] ] rr->length
+     * bytes of encrypted compressed stuff.
+     */
+
+    /* check is not needed I believe */
+    if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH) {
+        al = SSL_AD_RECORD_OVERFLOW;
+        SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
+        goto f_err;
+    }
+
+    /* decrypt in place in 'rr->input' */
+    rr->data = rr->input;
+    rr->orig_len = rr->length;
+
+    enc_err = s->method->ssl3_enc->enc(s, 0);
+    /*-
+     * enc_err is:
+     *    0: (in non-constant time) if the record is publically invalid.
+     *    1: if the padding is valid
+     *   -1: if the padding is invalid
+     */
+    if (enc_err == 0) {
+        /* For DTLS we simply ignore bad packets. */
+        rr->length = 0;
+        s->packet_length = 0;
+        goto err;
+    }
+#ifdef TLS_DEBUG
+    printf("dec %d\n", rr->length);
+    {
+        unsigned int z;
+        for (z = 0; z < rr->length; z++)
+            printf("%02X%c", rr->data[z], ((z + 1) % 16) ? ' ' : '\n');
+    }
+    printf("\n");
+#endif
+
+    /* r->length is now the compressed data plus mac */
+    if ((sess != NULL) &&
+        (s->enc_read_ctx != NULL) && (EVP_MD_CTX_md(s->read_hash) != NULL)) {
+        /* s->read_hash != NULL => mac_size != -1 */
+        unsigned char *mac = NULL;
+        unsigned char mac_tmp[EVP_MAX_MD_SIZE];
+        mac_size = EVP_MD_CTX_size(s->read_hash);
+        OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
+
+        /*
+         * orig_len is the length of the record before any padding was
+         * removed. This is public information, as is the MAC in use,
+         * therefore we can safely process the record in a different amount
+         * of time if it's too short to possibly contain a MAC.
+         */
+        if (rr->orig_len < mac_size ||
+            /* CBC records must have a padding length byte too. */
+            (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
+             rr->orig_len < mac_size + 1)) {
+            al = SSL_AD_DECODE_ERROR;
+            SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_LENGTH_TOO_SHORT);
+            goto f_err;
+        }
+
+        if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE) {
+            /*
+             * We update the length so that the TLS header bytes can be
+             * constructed correctly but we need to extract the MAC in
+             * constant time from within the record, without leaking the
+             * contents of the padding bytes.
+             */
+            mac = mac_tmp;
+            ssl3_cbc_copy_mac(mac_tmp, rr, mac_size);
+            rr->length -= mac_size;
+        } else {
+            /*
+             * In this case there's no padding, so |rec->orig_len| equals
+             * |rec->length| and we checked that there's enough bytes for
+             * |mac_size| above.
+             */
+            rr->length -= mac_size;
+            mac = &rr->data[rr->length];
+        }
+
+        i = s->method->ssl3_enc->mac(s, md, 0 /* not send */ );
+        if (i < 0 || mac == NULL
+            || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
+            enc_err = -1;
+        if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + mac_size)
+            enc_err = -1;
+    }
+
+    if (enc_err < 0) {
+        /* decryption failed, silently discard message */
+        rr->length = 0;
+        s->packet_length = 0;
+        goto err;
+    }
+
+    /* r->length is now just compressed */
+    if (s->expand != NULL) {
+        if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH) {
+            al = SSL_AD_RECORD_OVERFLOW;
+            SSLerr(SSL_F_DTLS1_PROCESS_RECORD,
+                   SSL_R_COMPRESSED_LENGTH_TOO_LONG);
+            goto f_err;
+        }
+        if (!ssl3_do_uncompress(s)) {
+            al = SSL_AD_DECOMPRESSION_FAILURE;
+            SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_BAD_DECOMPRESSION);
+            goto f_err;
+        }
+    }
+
+    if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH) {
+        al = SSL_AD_RECORD_OVERFLOW;
+        SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_DATA_LENGTH_TOO_LONG);
+        goto f_err;
+    }
+
+    rr->off = 0;
+    /*-
+     * So at this point the following is true
+     * ssl->s3->rrec.type   is the type of record
+     * ssl->s3->rrec.length == number of bytes in record
+     * ssl->s3->rrec.off    == offset to first valid byte
+     * ssl->s3->rrec.data   == where to take bytes from, increment
+     *                         after use :-).
+     */
+
+    /* we have pulled in a full packet so zero things */
+    s->packet_length = 0;
+    return (1);
+
+ f_err:
+    ssl3_send_alert(s, SSL3_AL_FATAL, al);
+ err:
+    return (0);
+}
+
+
+/*
+ * retrieve a buffered record that belongs to the current epoch, ie,
+ * processed
+ */
+#define dtls1_get_processed_record(s) \
+                   dtls1_retrieve_buffered_record((s), \
+                   &((s)->d1->processed_rcds))
+
+/*-
+ * Call this to get a new input record.
+ * It will return <= 0 if more data is needed, normally due to an error
+ * or non-blocking IO.
+ * When it finishes, one packet has been decoded and can be found in
+ * ssl->s3->rrec.type    - is the type of record
+ * ssl->s3->rrec.data,   - data
+ * ssl->s3->rrec.length, - number of bytes
+ */
+/* used only by dtls1_read_bytes */
+int dtls1_get_record(SSL *s)
+{
+    int ssl_major, ssl_minor;
+    int i, n;
+    SSL3_RECORD *rr;
+    unsigned char *p = NULL;
+    unsigned short version;
+    DTLS1_BITMAP *bitmap;
+    unsigned int is_next_epoch;
+
+    rr = RECORD_LAYER_get_rrec(&s->rlayer);
+
+    /*
+     * The epoch may have changed.  If so, process all the pending records.
+     * This is a non-blockin