Locking issues.
[openssl.git] / ssl / s3_pkt.c
index 38063b50d58d1472195931283f0ce1442d1aecd6..92d9a4ab1b4c166889bae564559e1ef94e3f5fc3 100644 (file)
@@ -56,7 +56,7 @@
  * [including the GNU Public Licence.]
  */
 /* ====================================================================
- * Copyright (c) 1998-1999 The OpenSSL Project.  All rights reserved.
+ * Copyright (c) 1998-2000 The OpenSSL Project.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -125,6 +125,7 @@ static int do_compress(SSL *ssl);
 static int do_uncompress(SSL *ssl);
 static int do_change_cipher_spec(SSL *ssl);
 
+/* used only by ssl3_get_record */
 static int ssl3_read_n(SSL *s, int n, int max, int extend)
        {
        /* If extend == 0, obtain new n-byte packet; if extend == 1, increase
@@ -167,6 +168,11 @@ static int ssl3_read_n(SSL *s, int n, int max, int extend)
                if (max > max_max)
                        max = max_max;
        }
+       if (n > max) /* does not happen */
+               {
+               SSLerr(SSL_F_SSL3_READ_N,SSL_R_INTERNAL_ERROR);
+               return -1;
+               }
 
        off = s->packet_length;
        newb = s->s3->rbuf.left;
@@ -179,7 +185,7 @@ static int ssl3_read_n(SSL *s, int n, int max, int extend)
                memmove(s->s3->rbuf.buf, s->packet, off+newb);
                s->packet = s->s3->rbuf.buf;
                }
-       
+
        while (newb < n)
                {
                /* Now we have off+newb bytes at the front of s->s3->rbuf.buf and need
@@ -209,6 +215,7 @@ static int ssl3_read_n(SSL *s, int n, int max, int extend)
        s->s3->rbuf.offset = off + n;
        s->s3->rbuf.left = newb - n;
        s->packet_length += n;
+       s->rwstate=SSL_NOTHING;
        return(n);
        }
 
@@ -220,11 +227,11 @@ static int ssl3_read_n(SSL *s, int n, int max, int extend)
  * ssl->s3->rrec.data,          - data
  * ssl->s3->rrec.length, - number of bytes
  */
+/* used only by ssl3_read_bytes */
 static int ssl3_get_record(SSL *s)
        {
        int ssl_major,ssl_minor,al;
        int n,i,ret= -1;
-       SSL3_BUFFER *rb;
        SSL3_RECORD *rr;
        SSL_SESSION *sess;
        unsigned char *p;
@@ -234,7 +241,6 @@ static int ssl3_get_record(SSL *s)
        int clear=0,extra;
 
        rr= &(s->s3->rrec);
-       rb= &(s->s3->rbuf);
        sess=s->session;
 
        if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
@@ -293,26 +299,26 @@ again:
                        goto f_err;
                        }
 
-               s->rstate=SSL_ST_READ_BODY;
+               /* now s->rstate == SSL_ST_READ_BODY */
                }
 
-       /* get and decode the data */
-       if (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))
                {
-               if (rr->length > (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 */
-                       }
-               s->rstate=SSL_ST_READ_HEADER;
+               /* 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 */
                }
 
-       /* At this point, we have the data in s->packet and there should be
-        * s->packet_length bytes, we must not 'overrun' this buffer :-)
-        * One of the following functions will copy the data from the
-        * s->packet buffer */
+       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'
@@ -322,13 +328,10 @@ again:
         * When the data is 'copied' into the rr->data buffer,
         * rr->input will be pointed at the new buffer */ 
 
-       /* Set the state for the following operations */
-       s->rstate=SSL_ST_READ_HEADER;
-
        /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
         * rr->length bytes of encrypted compressed stuff. */
 
-       /* check is not needed I belive */
+       /* check is not needed I believe */
        if (rr->length > (unsigned int)SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
                {
                al=SSL_AD_RECORD_OVERFLOW;
@@ -365,7 +368,7 @@ printf("\n");
                        SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PRE_MAC_LENGTH_TOO_LONG);
                        goto f_err;
                        }
-               /* check MAC for rr->input' */
+               /* check the MAC for rr->input (it's in mac_size bytes at the tail) */
                if (rr->length < mac_size)
                        {
                        al=SSL_AD_DECODE_ERROR;
@@ -465,12 +468,12 @@ static int do_compress(SSL *ssl)
        return(1);
        }
 
-/* Call this to write data
+/* 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.
  */
-int ssl3_write_bytes(SSL *s, int type, const void *_buf, int len)
+int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
        {
-       const unsigned char *buf=_buf;
+       const unsigned char *buf=buf_;
        unsigned int tot,n,nw;
        int i;
 
@@ -496,7 +499,7 @@ int ssl3_write_bytes(SSL *s, int type, const void *_buf, int len)
                        nw=SSL3_RT_MAX_PLAIN_LENGTH;
                else
                        nw=n;
-                       
+
                i=do_ssl3_write(s,type,&(buf[tot]),nw);
                if (i <= 0)
                        {
@@ -504,9 +507,6 @@ int ssl3_write_bytes(SSL *s, int type, const void *_buf, int len)
                        return(i);
                        }
 
-               if (type == SSL3_RT_HANDSHAKE)
-                       ssl3_finish_mac(s,&(buf[tot]),i);
-
                if ((i == (int)n) ||
                        (type == SSL3_RT_APPLICATION_DATA &&
                         (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
@@ -542,8 +542,8 @@ static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
                /* if it went, fall through and send more stuff */
                }
 
-       if (len <= 0) return(len);
-       
+       if (len == 0) return(len);
+
        wr= &(s->s3->wrec);
        wb= &(s->s3->wbuf);
        sess=s->session;
@@ -566,11 +566,11 @@ static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 
        *(p++)=(s->version>>8);
        *(p++)=s->version&0xff;
-       
+
        /* record where we are to write out packet length */
        plen=p; 
        p+=2;
-       
+
        /* lets setup the record stuff. */
        wr->data=p;
        wr->length=(int)len;
@@ -677,19 +677,81 @@ static int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
                }
        }
 
-int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len)
+/* Return up to 'len' payload bytes received in 'type' records.
+ * 'type' is one of the following:
+ *
+ *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
+ *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
+ *   -  0 (during a shutdown, no data has to be returned)
+ *
+ * If we don't have stored data to work from, read a SSL/TLS record first
+ * (possibly multiple records if we still don't have anything to return).
+ *
+ * This function must handle any surprises the peer may have for us, such as
+ * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
+ * a surprise, but handled as if it were), or renegotiation requests.
+ * Also if record payloads contain fragments too small to process, we store
+ * them until there is enough for the respective protocol (the record protocol
+ * may use arbitrary fragmentation and even interleaving):
+ *     Change cipher spec protocol
+ *             just 1 byte needed, no need for keeping anything stored
+ *     Alert protocol
+ *             2 bytes needed (AlertLevel, AlertDescription)
+ *     Handshake protocol
+ *             4 bytes needed (HandshakeType, uint24 length) -- we just have
+ *             to detect unexpected Client Hello and Hello Request messages
+ *             here, anything else is handled by higher layers
+ *     Application data protocol
+ *             none of our business
+ */
+int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
        {
-       int al,i,j,n,ret;
+       int al,i,j,ret;
+       unsigned int n;
        SSL3_RECORD *rr;
        void (*cb)()=NULL;
-       BIO *bio;
+
+       if (peek)
+               {
+               SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_FIXME); /* proper implementation not yet completed */
+               return -1;
+               }
 
        if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
                if (!ssl3_setup_buffers(s))
                        return(-1);
 
+       if ((type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type)
+               {
+               SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_INTERNAL_ERROR);
+               return -1;
+               }
+
+       if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
+               /* (partially) satisfy request from storage */
+               {
+               unsigned char *src = s->s3->handshake_fragment;
+               unsigned char *dst = buf;
+               unsigned int k;
+
+               n = 0;
+               while ((len > 0) && (s->s3->handshake_fragment_len > 0))
+                       {
+                       *dst++ = *src++;
+                       len--; s->s3->handshake_fragment_len--;
+                       n++;
+                       }
+               /* move any remaining fragment bytes: */
+               for (k = 0; k < s->s3->handshake_fragment_len; k++)
+                       s->s3->handshake_fragment[k] = *src++;
+               return n;
+       }
+
+       /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
+
        if (!s->in_handshake && SSL_in_init(s))
                {
+               /* type == SSL3_RT_APPLICATION_DATA */
                i=s->handshake_func(s);
                if (i < 0) return(i);
                if (i == 0)
@@ -705,7 +767,7 @@ start:
         * s->s3->rrec.data,    - data
         * s->s3->rrec.off,     - offset into 'data' for next read
         * s->s3->rrec.length,  - number of bytes. */
-       rr= &(s->s3->rrec);
+       rr = &(s->s3->rrec);
 
        /* get new packet */
        if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
@@ -716,7 +778,9 @@ start:
 
        /* we now have a packet which can be read and processed */
 
-       if (s->s3->change_cipher_spec && (rr->type != SSL3_RT_HANDSHAKE))
+       if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
+                                      * reset by ssl3_get_finished */
+               && (rr->type != SSL3_RT_HANDSHAKE))
                {
                al=SSL_AD_UNEXPECTED_MESSAGE;
                SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
@@ -731,13 +795,95 @@ start:
                return(0);
                }
 
-       /* Check for an incoming 'Hello Request' message from client */
-       if ((rr->type == SSL3_RT_HANDSHAKE) && (rr->length == 4) &&
-               (rr->data[0] == SSL3_MT_HELLO_REQUEST) &&
+
+       if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
+               {
+               /* make sure that we are not getting application data when we
+                * are doing a handshake for the first time */
+               if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
+                       (s->enc_read_ctx == NULL))
+                       {
+                       al=SSL_AD_UNEXPECTED_MESSAGE;
+                       SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
+                       goto f_err;
+                       }
+
+               if (len <= 0) return(len);
+
+               if ((unsigned int)len > rr->length)
+                       n = rr->length;
+               else
+                       n = (unsigned int)len;
+
+               memcpy(buf,&(rr->data[rr->off]),n);
+               rr->length-=n;
+               rr->off+=n;
+               if (rr->length == 0)
+                       {
+                       s->rstate=SSL_ST_READ_HEADER;
+                       rr->off=0;
+                       }
+               return(n);
+               }
+
+
+       /* If we get here, then type != rr->type; if we have a handshake
+        * message, 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.
+        */
+               {
+               unsigned int dest_maxlen = 0;
+               unsigned char *dest = NULL;
+               unsigned int *dest_len = NULL;
+
+               if (rr->type == SSL3_RT_HANDSHAKE)
+                       {
+                       dest_maxlen = sizeof s->s3->handshake_fragment;
+                       dest = s->s3->handshake_fragment;
+                       dest_len = &s->s3->handshake_fragment_len;
+                       }
+               else if (rr->type == SSL3_RT_ALERT)
+                       {
+                       dest_maxlen = sizeof s->s3->alert_fragment;
+                       dest = s->s3->alert_fragment;
+                       dest_len = &s->s3->alert_fragment_len;
+                       }
+
+               if (dest_maxlen > 0)
+                       {
+                       n = dest_maxlen - *dest_len; /* available space in 'dest' */
+                       if (rr->length < n)
+                               n = rr->length; /* available bytes */
+
+                       /* now move 'n' bytes: */
+                       while (n-- > 0)
+                               {
+                               dest[(*dest_len)++] = rr->data[rr->off++];
+                               rr->length--;
+                               }
+
+                       if (*dest_len < dest_maxlen)
+                               goto start; /* fragment was too small */
+                       }
+               }
+
+       /* s->s3->handshake_fragment_len == 4  iff  rr->type == SSL3_RT_HANDSHAKE;
+        * s->s3->alert_fragment_len == 2      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->s3->handshake_fragment_len >= 4) &&
+               (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
                (s->session != NULL) && (s->session->cipher != NULL))
                {
-               if ((rr->data[1] != 0) || (rr->data[2] != 0) ||
-                       (rr->data[3] != 0))
+               s->s3->handshake_fragment_len = 0;
+
+               if ((s->s3->handshake_fragment[1] != 0) ||
+                       (s->s3->handshake_fragment[2] != 0) ||
+                       (s->s3->handshake_fragment[3] != 0))
                        {
                        al=SSL_AD_DECODE_ERROR;
                        SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
@@ -751,220 +897,213 @@ start:
                        ssl3_renegotiate(s);
                        if (ssl3_renegotiate_check(s))
                                {
-                               n=s->handshake_func(s);
-                               if (n < 0) return(n);
-                               if (n == 0)
+                               i=s->handshake_func(s);
+                               if (i < 0) return(i);
+                               if (i == 0)
                                        {
                                        SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
                                        return(-1);
                                        }
+
+                               if (!(s->mode & SSL_MODE_AUTO_RETRY))
+                                       {
+                                       if (s->s3->rbuf.left == 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);
+                                               }
+                                       }
                                }
                        }
-               rr->length=0;
-/* ZZZ */      goto start;
+               /* we either finished a handshake or ignored the request,
+                * now try again to obtain the (application) data we were asked for */
+               goto start;
                }
 
-       /* if it is not the type we want, or we have shutdown and want
-        * the peer shutdown */
-       if ((rr->type != type) || (s->shutdown & SSL_SENT_SHUTDOWN))
+       if (s->s3->alert_fragment_len >= 2)
                {
-               if (rr->type == SSL3_RT_ALERT)
-                       {
-                       if ((rr->length != 2) || (rr->off != 0))
-                               {
-                               al=SSL_AD_DECODE_ERROR;
-                               SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_ALERT_RECORD);
-                               goto f_err;
-                               }
-
-                       i=rr->data[0];
-                       n=rr->data[1];
+               int alert_level = s->s3->alert_fragment[0];
+               int alert_descr = s->s3->alert_fragment[1];
 
-                       /* clear from buffer */
-                       rr->length=0;
+               s->s3->alert_fragment_len = 0;
 
-                       if (s->info_callback != NULL)
-                               cb=s->info_callback;
-                       else if (s->ctx->info_callback != NULL)
-                               cb=s->ctx->info_callback;
+               if (s->info_callback != NULL)
+                       cb=s->info_callback;
+               else if (s->ctx->info_callback != NULL)
+                       cb=s->ctx->info_callback;
 
-                       if (cb != NULL)
-                               {
-                               j=(i<<8)|n;
-                               cb(s,SSL_CB_READ_ALERT,j);
-                               }
+               if (cb != NULL)
+                       {
+                       j = (alert_level << 8) | alert_descr;
+                       cb(s, SSL_CB_READ_ALERT, j);
+                       }
 
-                       if (i == 1)
-                               {
-                               s->s3->warn_alert=n;
-                               if (n == SSL_AD_CLOSE_NOTIFY)
-                                       {
-                                       s->shutdown|=SSL_RECEIVED_SHUTDOWN;
-                                       return(0);
-                                       }
-                               }
-                       else if (i == 2)
+               if (alert_level == 1) /* warning */
+                       {
+                       s->s3->warn_alert = alert_descr;
+                       if (alert_descr == SSL_AD_CLOSE_NOTIFY)
                                {
-                               char tmp[16];
-
-                               s->rwstate=SSL_NOTHING;
-                               s->s3->fatal_alert=n;
-                               SSLerr(SSL_F_SSL3_READ_BYTES,
-                                       SSL_AD_REASON_OFFSET+n);
-                               sprintf(tmp,"%d",n);
-                               ERR_add_error_data(2,"SSL alert number ",tmp);
-                               s->shutdown|=SSL_RECEIVED_SHUTDOWN;
-                               SSL_CTX_remove_session(s->ctx,s->session);
+                               s->shutdown |= SSL_RECEIVED_SHUTDOWN;
                                return(0);
                                }
-                       else
-                               {
-                               al=SSL_AD_ILLEGAL_PARAMETER;
-                               SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
-                               goto f_err;
-                               }
-
-                       rr->length=0;
-                       goto start;
                        }
-
-               if (s->shutdown & SSL_SENT_SHUTDOWN)
+               else if (alert_level == 2) /* fatal */
                        {
+                       char tmp[16];
+
                        s->rwstate=SSL_NOTHING;
-                       rr->length=0;
+                       s->s3->fatal_alert = alert_descr;
+                       SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
+                       BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
+                       ERR_add_error_data(2,"SSL alert number ",tmp);
+                       s->shutdown|=SSL_RECEIVED_SHUTDOWN;
+                       SSL_CTX_remove_session(s->ctx,s->session);
                        return(0);
                        }
-
-               if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
+               else
                        {
-                       if (    (rr->length != 1) || (rr->off != 0) ||
-                               (rr->data[0] != SSL3_MT_CCS))
-                               {
-                               i=SSL_AD_ILLEGAL_PARAMETER;
-                               SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
-                               goto err;
-                               }
-
-                       rr->length=0;
-                       s->s3->change_cipher_spec=1;
-                       if (!do_change_cipher_spec(s))
-                               goto err;
-                       else
-                               goto start;
+                       al=SSL_AD_ILLEGAL_PARAMETER;
+                       SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
+                       goto f_err;
                        }
 
-               /* else we have a handshake */
-               if ((rr->type == SSL3_RT_HANDSHAKE) &&
-                       !s->in_handshake)
+               goto start;
+               }
+
+       if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
+               {
+               s->rwstate=SSL_NOTHING;
+               rr->length=0;
+               return(0);
+               }
+
+       if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
+               {
+               /* 'Change Cipher Spec' is just a single byte, so we know
+                * exactly what the record payload has to look like */
+               if (    (rr->length != 1) || (rr->off != 0) ||
+                       (rr->data[0] != SSL3_MT_CCS))
                        {
-                       if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
-                               !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
-                               {
-                               s->state=SSL_ST_BEFORE|(s->server)
-                                               ?SSL_ST_ACCEPT
-                                               :SSL_ST_CONNECT;
-                               s->new_session=1;
-                               }
-                       n=s->handshake_func(s);
-                       if (n < 0) return(n);
-                       if (n == 0)
-                               {
-                               SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
-                               return(-1);
-                               }
+                       i=SSL_AD_ILLEGAL_PARAMETER;
+                       SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
+                       goto err;
+                       }
 
-                       /* In the case where we try to read application data
-                        * the first time, but we trigger an SSL handshake, we
-                        * return -1 with the retry option set.  I do this
-                        * otherwise renegotiation can cause nasty problems 
-                        * in the non-blocking world */
+               rr->length=0;
+               s->s3->change_cipher_spec=1;
+               if (!do_change_cipher_spec(s))
+                       goto err;
+               else
+                       goto start;
+               }
 
-                       s->rwstate=SSL_READING;
-                       bio=SSL_get_rbio(s);
-                       BIO_clear_retry_flags(bio);
-                       BIO_set_retry_read(bio);
+       /* Unexpected handshake message (Client Hello, or protocol violation) */
+       if ((s->s3->handshake_fragment_len >= 4) &&     !s->in_handshake)
+               {
+               if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
+                       !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
+                       {
+#if 0 /* worked only because C operator preferences are not as expected (and
+       * because this is not really needed for clients except for detecting
+       * protocol violations): */
+                       s->state=SSL_ST_BEFORE|(s->server)
+                               ?SSL_ST_ACCEPT
+                               :SSL_ST_CONNECT;
+#else
+                       s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
+#endif
+                       s->new_session=1;
+                       }
+               i=s->handshake_func(s);
+               if (i < 0) return(i);
+               if (i == 0)
+                       {
+                       SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
                        return(-1);
                        }
 
-               switch (rr->type)
+               if (!(s->mode & SSL_MODE_AUTO_RETRY))
                        {
-               default:
-#ifndef NO_TLS
-                       /* TLS just ignores unknown message types */
-                       if (s->version == TLS1_VERSION)
-                               {
-                               goto start;
-                               }
-#endif
-               case SSL3_RT_CHANGE_CIPHER_SPEC:
-               case SSL3_RT_ALERT:
-               case SSL3_RT_HANDSHAKE:
-                       al=SSL_AD_UNEXPECTED_MESSAGE;
-                       SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
-                       goto f_err;
-               case SSL3_RT_APPLICATION_DATA:
-                       /* At this point, we were expecting something else,
-                        * but have application data.  What we do is set the
-                        * error, and return -1.  On the way out, if the
-                        * library was running inside ssl3_read() and it makes
-                        * sense to read application data at this point, we
-                        * will indulge it.  This will mostly happen during
-                        * session renegotiation.
-                        */
-                       if (s->s3->in_read_app_data &&
-                               (s->s3->total_renegotiations != 0) &&
-                               ((
-                                 (s->state & SSL_ST_CONNECT) &&
-                                 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
-                                 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
-                                ) || (
-                                 (s->state & SSL_ST_ACCEPT) &&
-                                 (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
-                                 (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
-                                )
-                               ))
+                       if (s->s3->rbuf.left == 0) /* no read-ahead left? */
                                {
-                               s->s3->in_read_app_data=0;
+                               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);
                                }
-                       else
-                               {
-                               al=SSL_AD_UNEXPECTED_MESSAGE;
-                               SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
-                               goto f_err;
-                               }
                        }
+               goto start;
                }
 
-       /* make sure that we are not getting application data when we
-        * are doing a handshake for the first time */
-       if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
-               (s->enc_read_ctx == NULL))
+       switch (rr->type)
                {
+       default:
+#ifndef NO_TLS
+               /* TLS just ignores unknown message types */
+               if (s->version == TLS1_VERSION)
+                       {
+                       goto start;
+                       }
+#endif
                al=SSL_AD_UNEXPECTED_MESSAGE;
-               SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
+               SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
                goto f_err;
+       case SSL3_RT_CHANGE_CIPHER_SPEC:
+       case SSL3_RT_ALERT:
+       case SSL3_RT_HANDSHAKE:
+               /* we already handled all of these, with the possible exception
+                * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
+                * should not happen when type != rr->type */
+               al=SSL_AD_UNEXPECTED_MESSAGE;
+               SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_INTERNAL_ERROR);
+               goto f_err;
+       case SSL3_RT_APPLICATION_DATA:
+               /* At this point, we were expecting handshake data,
+                * but have application data.  If the library was
+                * running inside ssl3_read() (i.e. in_read_app_data
+                * is set) and it makes sense to read application data
+                * at this point (session renegotiation not yet started),
+                * we will indulge it.
+                */
+               if (s->s3->in_read_app_data &&
+                       (s->s3->total_renegotiations != 0) &&
+                       ((
+                               (s->state & SSL_ST_CONNECT) &&
+                               (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
+                               (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
+                               ) || (
+                                       (s->state & SSL_ST_ACCEPT) &&
+                                       (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
+                                       (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
+                                       )
+                               ))
+                       {
+                       s->s3->in_read_app_data=0;
+                       return(-1);
+                       }
+               else
+                       {
+                       al=SSL_AD_UNEXPECTED_MESSAGE;
+                       SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
+                       goto f_err;
+                       }
                }
+       /* not reached */
 
-       if (len <= 0) return(len);
-
-       if ((unsigned int)len > rr->length)
-               n=rr->length;
-       else
-               n=len;
-
-       memcpy(buf,&(rr->data[rr->off]),(unsigned int)n);
-       rr->length-=n;
-       rr->off+=n;
-       if (rr->length <= 0)
-               {
-               s->rstate=SSL_ST_READ_HEADER;
-               rr->off=0;
-               }
-
-       if (type == SSL3_RT_HANDSHAKE)
-               ssl3_finish_mac(s,buf,n);
-       return(n);
 f_err:
        ssl3_send_alert(s,SSL3_AL_FATAL,al);
 err:
@@ -1013,20 +1152,6 @@ static int do_change_cipher_spec(SSL *s)
        return(1);
        }
 
-int ssl3_do_write(SSL *s, int type)
-       {
-       int ret;
-
-       ret=ssl3_write_bytes(s,type,&s->init_buf->data[s->init_off],
-                            s->init_num);
-       if (ret == s->init_num)
-               return(1);
-       if (ret < 0) return(-1);
-       s->init_off+=ret;
-       s->init_num-=ret;
-       return(0);
-       }
-
 void ssl3_send_alert(SSL *s, int level, int desc)
        {
        /* Map tls/ssl alert value to correct one */
@@ -1068,7 +1193,7 @@ int ssl3_dispatch_alert(SSL *s)
                        cb=s->info_callback;
                else if (s->ctx->info_callback != NULL)
                        cb=s->ctx->info_callback;
-               
+
                if (cb != NULL)
                        {
                        j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];