Add an error to the stack on failure in dtls1_write_bytes()
[openssl.git] / ssl / record / rec_layer_d1.c
index 14f9fc1020098e7c5ede32caae5337cc90c4e472..83f40943f3ca3773ddb6f88645fab606d627b2ce 100644 (file)
@@ -14,6 +14,7 @@
 #include <openssl/evp.h>
 #include <openssl/buffer.h>
 #include "record_locl.h"
+#include "../packet_locl.h"
 
 int DTLS_RECORD_LAYER_new(RECORD_LAYER *rl)
 {
@@ -108,19 +109,11 @@ void DTLS_RECORD_LAYER_set_saved_w_epoch(RECORD_LAYER *rl, unsigned short e)
     rl->d->w_epoch = e;
 }
 
-void DTLS_RECORD_LAYER_resync_write(RECORD_LAYER *rl)
-{
-    memcpy(rl->write_sequence, rl->read_sequence, sizeof(rl->write_sequence));
-}
-
 void DTLS_RECORD_LAYER_set_write_sequence(RECORD_LAYER *rl, unsigned char *seq)
 {
     memcpy(rl->write_sequence, seq, SEQ_NUM_SIZE);
 }
 
-static size_t have_handshake_fragment(SSL *s, int type, unsigned char *buf,
-                                      size_t len);
-
 /* copy buffered record into SSL structure */
 static int dtls1_copy_record(SSL *s, pitem *item)
 {
@@ -336,10 +329,10 @@ int dtls1_process_buffered_records(SSL *s)
  *             none of our business
  */
 int dtls1_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf,
-                     size_t len, int peek, size_t *read)
+                     size_t len, int peek, size_t *readbytes)
 {
     int al, i, j, iret;
-    size_t ret, n;
+    size_t n;
     SSL3_RECORD *rr;
     void (*cb) (const SSL *ssl, int type2, int val) = NULL;
 
@@ -356,33 +349,7 @@ int dtls1_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf,
         return -1;
     }
 
-    /*
-     * check whether there's a handshake message (client hello?) waiting
-     */
-    ret = have_handshake_fragment(s, type, buf, len);
-    if (ret > 0) {
-        *recvd_type = SSL3_RT_HANDSHAKE;
-        *read = ret;
-        return 1;
-    }
-
-    /*
-     * Now s->rlayer.d->handshake_fragment_len == 0 if
-     * type == SSL3_RT_HANDSHAKE.
-     */
-
-#ifndef OPENSSL_NO_SCTP
-    /*
-     * Continue handshake if it had to be interrupted to read app data with
-     * SCTP.
-     */
-    if ((!ossl_statem_get_in_handshake(s) && SSL_in_init(s)) ||
-        (BIO_dgram_is_sctp(SSL_get_rbio(s))
-         && ossl_statem_in_sctp_read_sock(s)
-         && s->s3->in_read_app_data != 2))
-#else
     if (!ossl_statem_get_in_handshake(s) && SSL_in_init(s))
-#endif
     {
         /* type == SSL3_RT_APPLICATION_DATA */
         i = s->handshake_func(s);
@@ -524,18 +491,6 @@ int dtls1_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf,
             }
         }
 #ifndef OPENSSL_NO_SCTP
-        /*
-         * We were about to renegotiate but had to read belated application
-         * data first, so retry.
-         */
-        if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
-            SSL3_RECORD_get_type(rr) == SSL3_RT_APPLICATION_DATA &&
-            ossl_statem_in_sctp_read_sock(s)) {
-            s->rwstate = SSL_READING;
-            BIO_clear_retry_flags(SSL_get_rbio(s));
-            BIO_set_retry_read(SSL_get_rbio(s));
-        }
-
         /*
          * We might had to delay a close_notify alert because of reordered
          * app data. If there was an alert and there is no message to read
@@ -548,7 +503,7 @@ int dtls1_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf,
             return 0;
         }
 #endif
-        *read = n;
+        *readbytes = n;
         return 1;
     }
 
@@ -557,170 +512,23 @@ int dtls1_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf,
      * then it was unexpected (Hello Request or Client Hello).
      */
 
-    /*
-     * In case of record types for which we have 'fragment' storage, fill
-     * that so that we can process the data at a fixed place.
-     */
-    {
-        size_t k, dest_maxlen = 0;
-        unsigned char *dest = NULL;
-        size_t *dest_len = NULL;
-
-        if (SSL3_RECORD_get_type(rr) == SSL3_RT_HANDSHAKE) {
-            dest_maxlen = sizeof s->rlayer.d->handshake_fragment;
-            dest = s->rlayer.d->handshake_fragment;
-            dest_len = &s->rlayer.d->handshake_fragment_len;
-        } else if (SSL3_RECORD_get_type(rr) == SSL3_RT_ALERT) {
-            dest_maxlen = sizeof(s->rlayer.d->alert_fragment);
-            dest = s->rlayer.d->alert_fragment;
-            dest_len = &s->rlayer.d->alert_fragment_len;
-        }
-#ifndef OPENSSL_NO_HEARTBEATS
-        else if (SSL3_RECORD_get_type(rr) == DTLS1_RT_HEARTBEAT) {
-            /* We allow a 0 return */
-            if (dtls1_process_heartbeat(s, SSL3_RECORD_get_data(rr),
-                                        SSL3_RECORD_get_length(rr)) < 0) {
-                return -1;
-            }
-            /* Exit and notify application to read again */
-            SSL3_RECORD_set_length(rr, 0);
-            s->rwstate = SSL_READING;
-            BIO_clear_retry_flags(SSL_get_rbio(s));
-            BIO_set_retry_read(SSL_get_rbio(s));
-            return -1;
-        }
-#endif
-        /* else it's a CCS message, or application data or wrong */
-        else if (SSL3_RECORD_get_type(rr) != SSL3_RT_CHANGE_CIPHER_SPEC) {
-            /*
-             * Application data while renegotiating is allowed. Try again
-             * reading.
-             */
-            if (SSL3_RECORD_get_type(rr) == SSL3_RT_APPLICATION_DATA) {
-                BIO *bio;
-                s->s3->in_read_app_data = 2;
-                bio = SSL_get_rbio(s);
-                s->rwstate = SSL_READING;
-                BIO_clear_retry_flags(bio);
-                BIO_set_retry_read(bio);
-                return -1;
-            }
+    if (SSL3_RECORD_get_type(rr) == SSL3_RT_ALERT) {
+        unsigned int alert_level, alert_descr;
+        unsigned char *alert_bytes = SSL3_RECORD_get_data(rr)
+                                     + SSL3_RECORD_get_off(rr);
+        PACKET alert;
 
-            /* Not certain if this is the right error handling */
+        if (!PACKET_buf_init(&alert, alert_bytes, SSL3_RECORD_get_length(rr))
+                || !PACKET_get_1(&alert, &alert_level)
+                || !PACKET_get_1(&alert, &alert_descr)
+                || PACKET_remaining(&alert) != 0) {
             al = SSL_AD_UNEXPECTED_MESSAGE;
-            SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
+            SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_INVALID_ALERT);
             goto f_err;
         }
 
-        if (dest_maxlen > 0) {
-            /*
-             * XDTLS: In a pathological case, the Client Hello may be
-             * fragmented--don't always expect dest_maxlen bytes
-             */
-            if (SSL3_RECORD_get_length(rr) < dest_maxlen) {
-#ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
-                /*
-                 * for normal alerts rr->length is 2, while
-                 * dest_maxlen is 7 if we were to handle this
-                 * non-existing alert...
-                 */
-                FIX ME;
-#endif
-                s->rlayer.rstate = SSL_ST_READ_HEADER;
-                SSL3_RECORD_set_length(rr, 0);
-                goto start;
-            }
-
-            /* now move 'n' bytes: */
-            for (k = 0; k < dest_maxlen; k++) {
-                dest[k] = SSL3_RECORD_get_data(rr)[SSL3_RECORD_get_off(rr)];
-                SSL3_RECORD_add_off(rr, 1);
-                SSL3_RECORD_add_length(rr, -1);
-            }
-            *dest_len = dest_maxlen;
-        }
-    }
-
-    /*-
-     * s->rlayer.d->handshake_fragment_len == 12  iff  rr->type == SSL3_RT_HANDSHAKE;
-     * s->rlayer.d->alert_fragment_len == 7      iff  rr->type == SSL3_RT_ALERT.
-     * (Possibly rr is 'empty' now, i.e. rr->length may be 0.)
-     */
-
-    /* If we are a client, check for an incoming 'Hello Request': */
-    if ((!s->server) &&
-        (s->rlayer.d->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
-        (s->rlayer.d->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
-        (s->session != NULL) && (s->session->cipher != NULL)) {
-        s->rlayer.d->handshake_fragment_len = 0;
-
-        if ((s->rlayer.d->handshake_fragment[1] != 0) ||
-            (s->rlayer.d->handshake_fragment[2] != 0) ||
-            (s->rlayer.d->handshake_fragment[3] != 0)) {
-            al = SSL_AD_DECODE_ERROR;
-            SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_BAD_HELLO_REQUEST);
-            goto f_err;
-        }
-
-        /*
-         * no need to check sequence number on HELLO REQUEST messages
-         */
-
         if (s->msg_callback)
-            s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
-                            s->rlayer.d->handshake_fragment, 4, s,
-                            s->msg_callback_arg);
-
-        if (SSL_is_init_finished(s) &&
-            !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
-            !s->s3->renegotiate) {
-            s->d1->handshake_read_seq++;
-            s->new_session = 1;
-            ssl3_renegotiate(s);
-            if (ssl3_renegotiate_check(s)) {
-                i = s->handshake_func(s);
-                if (i < 0)
-                    return i;
-                if (i == 0) {
-                    SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
-                    return -1;
-                }
-
-                if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
-                    if (SSL3_BUFFER_get_left(&s->rlayer.rbuf) == 0) {
-                        /* no read-ahead left? */
-                        BIO *bio;
-                        /*
-                         * In the case where we try to read application data,
-                         * but we trigger an SSL handshake, we return -1 with
-                         * the retry option set.  Otherwise renegotiation may
-                         * cause nasty problems in the blocking world
-                         */
-                        s->rwstate = SSL_READING;
-                        bio = SSL_get_rbio(s);
-                        BIO_clear_retry_flags(bio);
-                        BIO_set_retry_read(bio);
-                        return -1;
-                    }
-                }
-            }
-        }
-        /*
-         * we either finished a handshake or ignored the request, now try
-         * again to obtain the (application) data we were asked for
-         */
-        goto start;
-    }
-
-    if (s->rlayer.d->alert_fragment_len >= DTLS1_AL_HEADER_LENGTH) {
-        int alert_level = s->rlayer.d->alert_fragment[0];
-        int alert_descr = s->rlayer.d->alert_fragment[1];
-
-        s->rlayer.d->alert_fragment_len = 0;
-
-        if (s->msg_callback)
-            s->msg_callback(0, s->version, SSL3_RT_ALERT,
-                            s->rlayer.d->alert_fragment, 2, s,
+            s->msg_callback(0, s->version, SSL3_RT_ALERT, alert_bytes, 2, s,
                             s->msg_callback_arg);
 
         if (s->info_callback != NULL)
@@ -762,34 +570,6 @@ int dtls1_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf,
                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
                 return 0;
             }
-#if 0
-            /* XXX: this is a possible improvement in the future */
-            /* now check if it's a missing record */
-            if (alert_descr == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE) {
-                unsigned short seq;
-                unsigned int frag_off;
-                unsigned char *p = &(s->rlayer.d->alert_fragment[2]);
-
-                n2s(p, seq);
-                n2l3(p, frag_off);
-
-                dtls1_retransmit_message(s,
-                                         dtls1_get_queue_priority
-                                         (frag->msg_header.seq, 0), frag_off,
-                                         &found);
-                if (!found && SSL_in_init(s)) {
-                    /*
-                     * fprintf( stderr,"in init = %d\n", SSL_in_init(s));
-                     */
-                    /*
-                     * requested a message not yet sent, send an alert
-                     * ourselves
-                     */
-                    ssl3_send_alert(s, SSL3_AL_WARNING,
-                                    DTLS1_AD_MISSING_HANDSHAKE_MESSAGE);
-                }
-            }
-#endif
         } else if (alert_level == SSL3_AL_FATAL) {
             char tmp[16];
 
@@ -829,17 +609,22 @@ int dtls1_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf,
     /*
      * Unexpected handshake message (Client Hello, or protocol violation)
      */
-    if ((s->rlayer.d->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
-        !ossl_statem_get_in_handshake(s)) {
+    if ((SSL3_RECORD_get_type(rr) == SSL3_RT_HANDSHAKE) &&
+            !ossl_statem_get_in_handshake(s)) {
         struct hm_header_st msg_hdr;
 
-        /* this may just be a stale retransmit */
-        dtls1_get_message_header(rr->data, &msg_hdr);
-        if (SSL3_RECORD_get_epoch(rr) != s->rlayer.d->r_epoch) {
+        /*
+         * This may just be a stale retransmit. Also sanity check that we have
+         * at least enough record bytes for a message header
+         */
+        if (SSL3_RECORD_get_epoch(rr) != s->rlayer.d->r_epoch
+                || SSL3_RECORD_get_length(rr) < DTLS1_HM_HEADER_LENGTH) {
             SSL3_RECORD_set_length(rr, 0);
             goto start;
         }
 
+        dtls1_get_message_header(rr->data, &msg_hdr);
+
         /*
          * If we are server, we may have a repeated FINISHED of the client
          * here, then retransmit our CCS and FINISHED.
@@ -853,12 +638,21 @@ int dtls1_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf,
             goto start;
         }
 
-        if (SSL_is_init_finished(s) &&
-            !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) {
-            ossl_statem_set_in_init(s, 1);
-            s->renegotiate = 1;
-            s->new_session = 1;
+        /*
+         * To get here we must be trying to read app data but found handshake
+         * data. But if we're trying to read app data, and we're not in init
+         * (which is tested for at the top of this function) then init must be
+         * finished
+         */
+        if (!ossl_assert(SSL_is_init_finished(s))) {
+            al = SSL_AD_INTERNAL_ERROR;
+            SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
+            goto f_err;
         }
+
+        /* We found handshake data, so we're going back into init */
+        ossl_statem_set_in_init(s, 1);
+
         i = s->handshake_func(s);
         if (i < 0)
             return i;
@@ -889,11 +683,6 @@ int dtls1_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf,
 
     switch (SSL3_RECORD_get_type(rr)) {
     default:
-        /* TLS just ignores unknown message types */
-        if (s->version == TLS1_VERSION) {
-            SSL3_RECORD_set_length(rr, 0);
-            goto start;
-        }
         al = SSL_AD_UNEXPECTED_MESSAGE;
         SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
         goto f_err;
@@ -934,39 +723,6 @@ int dtls1_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf,
     return -1;
 }
 
-/*
- * this only happens when a client hello is received and a handshake
- * is started.
- */
-static size_t have_handshake_fragment(SSL *s, int type, unsigned char *buf,
-                                      size_t len)
-{
-
-    if ((type == SSL3_RT_HANDSHAKE)
-        && (s->rlayer.d->handshake_fragment_len > 0))
-        /* (partially) satisfy request from storage */
-    {
-        unsigned char *src = s->rlayer.d->handshake_fragment;
-        unsigned char *dst = buf;
-        size_t k, n;
-
-        /* peek == 0 */
-        n = 0;
-        while ((len > 0) && (s->rlayer.d->handshake_fragment_len > 0)) {
-            *dst++ = *src++;
-            len--;
-            s->rlayer.d->handshake_fragment_len--;
-            n++;
-        }
-        /* move any remaining fragment bytes: */
-        for (k = 0; k < s->rlayer.d->handshake_fragment_len; k++)
-            s->rlayer.d->handshake_fragment[k] = *src++;
-        return n;
-    }
-
-    return 0;
-}
-
 /*
  * Call this to write data in records of type 'type' It will return <= 0 if
  * not all data has been sent or non-blocking IO.
@@ -976,7 +732,10 @@ int dtls1_write_bytes(SSL *s, int type, const void *buf, size_t len,
 {
     int i;
 
-    OPENSSL_assert(len <= SSL3_RT_MAX_PLAIN_LENGTH);
+    if (!ossl_assert(len <= SSL3_RT_MAX_PLAIN_LENGTH)) {
+        SSLerr(SSL_F_DTLS1_WRITE_BYTES, ERR_R_INTERNAL_ERROR);
+        return -1;
+    }
     s->rwstate = SSL_NOTHING;
     i = do_dtls1_write(s, type, buf, len, 0, written);
     return i;
@@ -999,9 +758,9 @@ int do_dtls1_write(SSL *s, int type, const unsigned char *buf,
      * first check if there is a SSL3_BUFFER still being written out.  This
      * will happen with non blocking IO
      */
-    if (SSL3_BUFFER_get_left(wb) != 0) {
-        OPENSSL_assert(0);      /* XDTLS: want to see if we ever get here */
-        return ssl3_write_pending(s, type, buf, len, written);
+    if (!ossl_assert(SSL3_BUFFER_get_left(wb) == 0)) {
+        SSLerr(SSL_F_DO_DTLS1_WRITE, ERR_R_INTERNAL_ERROR);
+        return 0;
     }
 
     /* If we have an alert to send, lets send it */
@@ -1015,6 +774,11 @@ int do_dtls1_write(SSL *s, int type, const unsigned char *buf,
     if (len == 0 && !create_empty_fragment)
         return 0;
 
+    if (len > s->max_send_fragment) {
+        SSLerr(SSL_F_DO_DTLS1_WRITE, SSL_R_EXCEEDS_MAX_FRAGMENT_SIZE);
+        return 0;
+    }
+
     sess = s->session;
 
     if ((sess == NULL) ||
@@ -1098,10 +862,10 @@ int do_dtls1_write(SSL *s, int type, const unsigned char *buf,
      * wb->buf
      */
 
-    if (!SSL_USE_ETM(s) && mac_size != 0) {
-        if (s->method->ssl3_enc->mac(s, &wr,
-                                     &(p[SSL3_RECORD_get_length(&wr) + eivlen]),
-                                     1) < 0)
+    if (!SSL_WRITE_ETM(s) && mac_size != 0) {
+        if (!s->method->ssl3_enc->mac(s, &wr,
+                                      &(p[SSL3_RECORD_get_length(&wr) + eivlen]),
+                                      1))
             goto err;
         SSL3_RECORD_add_length(&wr, mac_size);
     }
@@ -1116,29 +880,19 @@ int do_dtls1_write(SSL *s, int type, const unsigned char *buf,
     if (s->method->ssl3_enc->enc(s, &wr, 1, 1) < 1)
         goto err;
 
-    if (SSL_USE_ETM(s) && mac_size != 0) {
-        if (s->method->ssl3_enc->mac(s, &wr,
-                                     &(p[SSL3_RECORD_get_length(&wr)]),
-                                     1) < 0)
+    if (SSL_WRITE_ETM(s) && mac_size != 0) {
+        if (!s->method->ssl3_enc->mac(s, &wr,
+                                      &(p[SSL3_RECORD_get_length(&wr)]), 1))
             goto err;
         SSL3_RECORD_add_length(&wr, mac_size);
     }
 
     /* record length after mac and block padding */
-    /*
-     * if (type == SSL3_RT_APPLICATION_DATA || (type == SSL3_RT_ALERT && !
-     * SSL_in_init(s)))
-     */
 
     /* there's only one epoch between handshake and app data */
 
     s2n(s->rlayer.d->w_epoch, pseq);
 
-    /* XDTLS: ?? */
-    /*
-     * else s2n(s->d1->handshake_epoch, pseq);
-     */
-
     memcpy(pseq, &(s->rlayer.write_sequence[2]), 6);
     pseq += 6;
     s2n(SSL3_RECORD_get_length(&wr), pseq);