X-Git-Url: https://git.openssl.org/gitweb/?p=openssl.git;a=blobdiff_plain;f=ssl%2Fs3_pkt.c;h=032a8558ed1765c90363810eab8f4511739d7a87;hp=d0f54e297bb7af5e53ff732363c5c6c85b530dd4;hb=e33ac0e71d9ea52143333223a318b38f3ce1ee52;hpb=09b6c2ef15139aa6ef2cee11676070939dd37817

diff --git a/ssl/s3_pkt.c b/ssl/s3_pkt.c
index d0f54e297b..032a8558ed 100644
--- a/ssl/s3_pkt.c
+++ b/ssl/s3_pkt.c
@@ -115,6 +115,7 @@
 #include "ssl_locl.h"
 #include <openssl/evp.h>
 #include <openssl/buffer.h>
+#include <openssl/rand.h>
 
 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 			 unsigned int len, int create_empty_fragment);
@@ -129,73 +130,113 @@ int ssl3_read_n(SSL *s, int n, int max, int extend)
 	 * (If s->read_ahead is set, 'max' bytes may be stored in rbuf
 	 * [plus s->packet_length bytes if extend == 1].)
 	 */
-	int i,off,newb;
+	int i,len,left;
+	long align=0;
+	unsigned char *pkt;
+	SSL3_BUFFER *rb;
+
+	if (n <= 0) return n;
+
+	rb    = &(s->s3->rbuf);
+	if (rb->buf == NULL)
+		if (!ssl3_setup_read_buffer(s))
+			return -1;
+
+	left  = rb->left;
+#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
+	align = (long)rb->buf + SSL3_RT_HEADER_LENGTH;
+	align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
+#endif
 
 	if (!extend)
 		{
 		/* start with empty packet ... */
-		if (s->s3->rbuf.left == 0)
-			s->s3->rbuf.offset = 0;
-		s->packet = s->s3->rbuf.buf + s->s3->rbuf.offset;
+		if (left == 0)
+			rb->offset = align;
+		else if (align != 0 && left >= SSL3_RT_HEADER_LENGTH)
+			{
+			/* check if next packet length is large
+			 * enough to justify payload alignment... */
+			pkt = rb->buf + rb->offset;
+			if (pkt[0] == SSL3_RT_APPLICATION_DATA
+			    && (pkt[3]<<8|pkt[4]) >= 128)
+				{
+				/* Note that even if packet is corrupted
+				 * and its length field is insane, we can
+				 * only be led to wrong decision about
+				 * whether memmove will occur or not.
+				 * Header values has no effect on memmove
+				 * arguments and therefore no buffer
+				 * overrun can be triggered. */
+				memmove (rb->buf+align,pkt,left);
+				rb->offset = align;
+				}
+			}
+		s->packet = rb->buf + rb->offset;
 		s->packet_length = 0;
 		/* ... now we can act as if 'extend' was set */
 		}
 
-	/* extend reads should not span multiple packets for DTLS */
-	if ( SSL_version(s) == DTLS1_VERSION &&
-		extend)
+	/* For DTLS/UDP reads should not span multiple packets
+	 * because the read operation returns the whole packet
+	 * at once (as long as it fits into the buffer). */
+	if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER)
 		{
-		if ( s->s3->rbuf.left > 0 && n > s->s3->rbuf.left)
-			n = s->s3->rbuf.left;
+		if (left > 0 && n > left)
+			n = left;
 		}
 
 	/* if there is enough in the buffer from a previous read, take some */
-	if (s->s3->rbuf.left >= (int)n)
+	if (left >= n)
 		{
 		s->packet_length+=n;
-		s->s3->rbuf.left-=n;
-		s->s3->rbuf.offset+=n;
+		rb->left=left-n;
+		rb->offset+=n;
 		return(n);
 		}
 
 	/* else we need to read more data */
-	if (!s->read_ahead)
-		max=n;
 
-	{
-		/* avoid buffer overflow */
-		int max_max = s->s3->rbuf.len - s->packet_length;
-		if (max > max_max)
-			max = max_max;
-	}
-	if (n > max) /* does not happen */
+	len = s->packet_length;
+	pkt = rb->buf+align;
+	/* Move any available bytes to front of buffer:
+	 * 'len' bytes already pointed to by 'packet',
+	 * 'left' extra ones at the end */
+	if (s->packet != pkt) /* len > 0 */
+		{
+		memmove(pkt, s->packet, len+left);
+		s->packet = pkt;
+		rb->offset = len + align;
+		}
+
+	if (n > (int)(rb->len - rb->offset)) /* does not happen */
 		{
 		SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR);
 		return -1;
 		}
 
-	off = s->packet_length;
-	newb = s->s3->rbuf.left;
-	/* Move any available bytes to front of buffer:
-	 * 'off' bytes already pointed to by 'packet',
-	 * 'newb' extra ones at the end */
-	if (s->packet != s->s3->rbuf.buf)
+	if (!s->read_ahead)
+		/* ignore max parameter */
+		max = n;
+	else
 		{
-		/*  off > 0 */
-		memmove(s->s3->rbuf.buf, s->packet, off+newb);
-		s->packet = s->s3->rbuf.buf;
+		if (max < n)
+			max = n;
+		if (max > (int)(rb->len - rb->offset))
+			max = rb->len - rb->offset;
 		}
 
-	while (newb < n)
+	while (left < n)
 		{
-		/* Now we have off+newb bytes at the front of s->s3->rbuf.buf and need
-		 * to read in more until we have off+n (up to off+max if possible) */
+		/* Now we have len+left bytes at the front of s->s3->rbuf.buf
+		 * and need to read in more until we have len+n (up to
+		 * len+max if possible) */
 
 		clear_sys_error();
 		if (s->rbio != NULL)
 			{
 			s->rwstate=SSL_READING;
-			i=BIO_read(s->rbio,	&(s->s3->rbuf.buf[off+newb]), max-newb);
+			i=BIO_read(s->rbio,pkt+len+left, max-left);
 			}
 		else
 			{
@@ -205,15 +246,27 @@ int ssl3_read_n(SSL *s, int n, int max, int extend)
 
 		if (i <= 0)
 			{
-			s->s3->rbuf.left = newb;
+			rb->left = left;
+			if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
+			    SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
+				if (len+left == 0)
+					ssl3_release_read_buffer(s);
 			return(i);
 			}
-		newb+=i;
+		left+=i;
+		/* reads should *never* span multiple packets for DTLS because
+		 * the underlying transport protocol is message oriented as opposed
+		 * to byte oriented as in the TLS case. */
+		if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER)
+			{
+			if (n > left)
+				n = left; /* makes the while condition false */
+			}
 		}
 
 	/* done reading, now the book-keeping */
-	s->s3->rbuf.offset = off + n;
-	s->s3->rbuf.left = newb - n;
+	rb->offset += n;
+	rb->left = left - n;
 	s->packet_length += n;
 	s->rwstate=SSL_NOTHING;
 	return(n);
@@ -237,11 +290,8 @@ static int ssl3_get_record(SSL *s)
 	unsigned char *p;
 	unsigned char md[EVP_MAX_MD_SIZE];
 	short version;
-	unsigned int mac_size;
-	int clear=0;
+	unsigned mac_size;
 	size_t extra;
-	int decryption_failed_or_bad_record_mac = 0;
-	unsigned char *mac = NULL;
 
 	rr= &(s->s3->rrec);
 	sess=s->session;
@@ -250,9 +300,9 @@ static int ssl3_get_record(SSL *s)
 		extra=SSL3_RT_MAX_EXTRA;
 	else
 		extra=0;
-	if (extra != s->s3->rbuf.len - SSL3_RT_MAX_PACKET_SIZE)
+	if (extra && !s->s3->init_extra)
 		{
-		/* actually likely an application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER
+		/* 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;
@@ -268,6 +318,8 @@ again:
 		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++);
@@ -275,20 +327,19 @@ again:
 		ssl_minor= *(p++);
 		version=(ssl_major<<8)|ssl_minor;
 		n2s(p,rr->length);
+#if 0
+fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length);
+#endif
 
 		/* Lets check version */
-		if (s->first_packet)
-			{
-			s->first_packet=0;
-			}
-		else
+		if (!s->first_packet)
 			{
 			if (version != s->version)
 				{
 				SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
-				/* Send back error using their
-				 * version number :-) */
-				s->version=version;
+                                if ((s->version & 0xFF00) == (version & 0xFF00))
+                                	/* Send back error using their minor version number :-) */
+					s->version = (unsigned short)version;
 				al=SSL_AD_PROTOCOL_VERSION;
 				goto f_err;
 				}
@@ -300,7 +351,7 @@ again:
 			goto err;
 			}
 
-		if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
+		if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH)
 			{
 			al=SSL_AD_RECORD_OVERFLOW;
 			SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
@@ -349,19 +400,18 @@ again:
 
 	/* decrypt in place in 'rr->input' */
 	rr->data=rr->input;
+	rr->orig_len=rr->length;
 
 	enc_err = s->method->ssl3_enc->enc(s,0);
-	if (enc_err <= 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)
 		{
-		if (enc_err == 0)
-			/* SSLerr() and ssl3_send_alert() have been called */
-			goto err;
-
-		/* Otherwise enc_err == -1, which indicates bad padding
-		 * (rec->length has not been changed in this case).
-		 * To minimize information leaked via timing, we will perform
-		 * the MAC computation anyway. */
-		decryption_failed_or_bad_record_mac = 1;
+		al=SSL_AD_DECRYPTION_FAILED;
+		SSLerr(SSL_F_TLS1_ENC,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
+		goto f_err;
 		}
 
 #ifdef TLS_DEBUG
@@ -371,51 +421,59 @@ printf("\n");
 #endif
 
 	/* r->length is now the compressed data plus mac */
-	if (	(sess == NULL) ||
-		(s->enc_read_ctx == NULL) ||
-		(s->read_hash == NULL))
-		clear=1;
-
-	if (!clear)
+	if ((sess != NULL) &&
+	    (s->enc_read_ctx != NULL) &&
+	    (EVP_MD_CTX_md(s->read_hash) != NULL))
 		{
-		mac_size=EVP_MD_size(s->read_hash);
-
-		if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
+		/* 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))
 			{
-#if 0 /* OK only for stream ciphers (then rr->length is visible from ciphertext anyway) */
-			al=SSL_AD_RECORD_OVERFLOW;
-			SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PRE_MAC_LENGTH_TOO_LONG);
+			al=SSL_AD_DECODE_ERROR;
+			SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
 			goto f_err;
-#else
-			decryption_failed_or_bad_record_mac = 1;
-#endif			
 			}
-		/* check the MAC for rr->input (it's in mac_size bytes at the tail) */
-		if (rr->length >= mac_size)
+
+		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;
-			mac = &rr->data[rr->length];
 			}
 		else
 			{
-			/* record (minus padding) is too short to contain a MAC */
-#if 0 /* OK only for stream ciphers */
-			al=SSL_AD_DECODE_ERROR;
-			SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
-			goto f_err;
-#else
-			decryption_failed_or_bad_record_mac = 1;
-			rr->length = 0;
-#endif
-			}
-		i=s->method->ssl3_enc->mac(s,md,0);
-		if (mac == NULL || memcmp(md, mac, mac_size) != 0)
-			{
-			decryption_failed_or_bad_record_mac = 1;
+			/* 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 (decryption_failed_or_bad_record_mac)
+	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
@@ -466,6 +524,10 @@ printf("\n");
 	/* just read a 0 length packet */
 	if (rr->length == 0) goto again;
 
+#if 0
+fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length);
+#endif
+
 	return(1);
 
 f_err:
@@ -539,8 +601,8 @@ int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
 	n=(len-tot);
 	for (;;)
 		{
-		if (n > SSL3_RT_MAX_PLAIN_LENGTH)
-			nw=SSL3_RT_MAX_PLAIN_LENGTH;
+		if (n > s->max_send_fragment)
+			nw=s->max_send_fragment;
 		else
 			nw=n;
 
@@ -572,14 +634,20 @@ static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 	{
 	unsigned char *p,*plen;
 	int i,mac_size,clear=0;
-	int prefix_len = 0;
+	int prefix_len=0;
+	int eivlen;
+	long align=0;
 	SSL3_RECORD *wr;
-	SSL3_BUFFER *wb;
+	SSL3_BUFFER *wb=&(s->s3->wbuf);
 	SSL_SESSION *sess;
 
+ 	if (wb->buf == NULL)
+		if (!ssl3_setup_write_buffer(s))
+			return -1;
+
 	/* first check if there is a SSL3_BUFFER still being written
 	 * out.  This will happen with non blocking IO */
-	if (s->s3->wbuf.left != 0)
+	if (wb->left != 0)
 		return(ssl3_write_pending(s,type,buf,len));
 
 	/* If we have an alert to send, lets send it */
@@ -595,18 +663,25 @@ static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 		return 0;
 
 	wr= &(s->s3->wrec);
-	wb= &(s->s3->wbuf);
 	sess=s->session;
 
 	if (	(sess == NULL) ||
 		(s->enc_write_ctx == NULL) ||
-		(s->write_hash == NULL))
+		(EVP_MD_CTX_md(s->write_hash) == NULL))
+		{
+#if 1
+		clear=s->enc_write_ctx?0:1;	/* must be AEAD cipher */
+#else
 		clear=1;
-
-	if (clear)
+#endif
 		mac_size=0;
+		}
 	else
-		mac_size=EVP_MD_size(s->write_hash);
+		{
+		mac_size=EVP_MD_CTX_size(s->write_hash);
+		if (mac_size < 0)
+			goto err;
+		}
 
 	/* 'create_empty_fragment' is true only when this function calls itself */
 	if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done)
@@ -624,7 +699,8 @@ static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 			if (prefix_len <= 0)
 				goto err;
 
-			if (s->s3->wbuf.len < (size_t)prefix_len + SSL3_RT_MAX_PACKET_SIZE)
+			if (prefix_len >
+		(SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD))
 				{
 				/* insufficient space */
 				SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
@@ -635,7 +711,32 @@ static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 		s->s3->empty_fragment_done = 1;
 		}
 
-	p = wb->buf + prefix_len;
+	if (create_empty_fragment)
+		{
+#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
+		/* extra fragment would be couple of cipher blocks,
+		 * which would be multiple of SSL3_ALIGN_PAYLOAD, so
+		 * if we want to align the real payload, then we can
+		 * just pretent we simply have two headers. */
+		align = (long)wb->buf + 2*SSL3_RT_HEADER_LENGTH;
+		align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
+#endif
+		p = wb->buf + align;
+		wb->offset  = align;
+		}
+	else if (prefix_len)
+		{
+		p = wb->buf + wb->offset + prefix_len;
+		}
+	else
+		{
+#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
+		align = (long)wb->buf + SSL3_RT_HEADER_LENGTH;
+		align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
+#endif
+		p = wb->buf + align;
+		wb->offset  = align;
+		}
 
 	/* write the header */
 
@@ -643,14 +744,40 @@ static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 	wr->type=type;
 
 	*(p++)=(s->version>>8);
-	*(p++)=s->version&0xff;
+	/* Some servers hang if iniatial client hello is larger than 256
+	 * bytes and record version number > TLS 1.0
+	 */
+	if (s->state == SSL3_ST_CW_CLNT_HELLO_B
+				&& !s->renegotiate
+				&& TLS1_get_version(s) > TLS1_VERSION)
+		*(p++) = 0x1;
+	else
+		*(p++)=s->version&0xff;
 
 	/* field where we are to write out packet length */
 	plen=p; 
 	p+=2;
+	/* Explicit IV length, block ciphers and TLS version 1.1 or later */
+	if (s->enc_write_ctx && s->version >= TLS1_1_VERSION)
+		{
+		int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
+		if (mode == EVP_CIPH_CBC_MODE)
+			{
+			eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
+			if (eivlen <= 1)
+				eivlen = 0;
+			}
+		/* Need explicit part of IV for GCM mode */
+		else if (mode == EVP_CIPH_GCM_MODE)
+			eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
+		else
+			eivlen = 0;
+		}
+	else 
+		eivlen = 0;
 
 	/* lets setup the record stuff. */
-	wr->data=p;
+	wr->data=p + eivlen;
 	wr->length=(int)len;
 	wr->input=(unsigned char *)buf;
 
@@ -678,10 +805,19 @@ static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 
 	if (mac_size != 0)
 		{
-		s->method->ssl3_enc->mac(s,&(p[wr->length]),1);
+		if (s->method->ssl3_enc->mac(s,&(p[wr->length + eivlen]),1) < 0)
+			goto err;
 		wr->length+=mac_size;
-		wr->input=p;
-		wr->data=p;
+		}
+
+	wr->input=p;
+	wr->data=p;
+
+	if (eivlen)
+		{
+	/*	if (RAND_pseudo_bytes(p, eivlen) <= 0)
+			goto err; */
+		wr->length += eivlen;
 		}
 
 	/* ssl3_enc can only have an error on read */
@@ -690,6 +826,9 @@ static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 	/* record length after mac and block padding */
 	s2n(wr->length,plen);
 
+	if (s->msg_callback)
+		s->msg_callback(1, 0, SSL3_RT_HEADER, plen - 5, 5, s, s->msg_callback_arg);
+
 	/* we should now have
 	 * wr->data pointing to the encrypted data, which is
 	 * wr->length long */
@@ -706,7 +845,6 @@ static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
 
 	/* now let's set up wb */
 	wb->left = prefix_len + wr->length;
-	wb->offset = 0;
 
 	/* memorize arguments so that ssl3_write_pending can detect bad write retries later */
 	s->s3->wpend_tot=len;
@@ -725,6 +863,7 @@ int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
 	unsigned int len)
 	{
 	int i;
+	SSL3_BUFFER *wb=&(s->s3->wbuf);
 
 /* XXXX */
 	if ((s->s3->wpend_tot > (int)len)
@@ -743,24 +882,35 @@ int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
 			{
 			s->rwstate=SSL_WRITING;
 			i=BIO_write(s->wbio,
-				(char *)&(s->s3->wbuf.buf[s->s3->wbuf.offset]),
-				(unsigned int)s->s3->wbuf.left);
+				(char *)&(wb->buf[wb->offset]),
+				(unsigned int)wb->left);
 			}
 		else
 			{
 			SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
 			i= -1;
 			}
-		if (i == s->s3->wbuf.left)
+		if (i == wb->left)
 			{
-			s->s3->wbuf.left=0;
+			wb->left=0;
+			wb->offset+=i;
+			if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
+			    SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
+				ssl3_release_write_buffer(s);
 			s->rwstate=SSL_NOTHING;
 			return(s->s3->wpend_ret);
 			}
-		else if (i <= 0)
+		else if (i <= 0) {
+			if (s->version == DTLS1_VERSION ||
+			    s->version == DTLS1_BAD_VER) {
+				/* For DTLS, just drop it. That's kind of the whole
+				   point in using a datagram service */
+				wb->left = 0;
+			}
 			return(i);
-		s->s3->wbuf.offset+=i;
-		s->s3->wbuf.left-=i;
+		}
+		wb->offset+=i;
+		wb->left-=i;
 		}
 	}
 
@@ -799,7 +949,7 @@ int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
 	void (*cb)(const SSL *ssl,int type2,int val)=NULL;
 
 	if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
-		if (!ssl3_setup_buffers(s))
+		if (!ssl3_setup_read_buffer(s))
 			return(-1);
 
 	if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type) ||
@@ -908,6 +1058,8 @@ start:
 				{
 				s->rstate=SSL_ST_READ_HEADER;
 				rr->off=0;
+				if (s->mode & SSL_MODE_RELEASE_BUFFERS)
+					ssl3_release_read_buffer(s);
 				}
 			}
 		return(n);
@@ -937,6 +1089,19 @@ start:
 			dest = s->s3->alert_fragment;
 			dest_len = &s->s3->alert_fragment_len;
 			}
+#ifndef OPENSSL_NO_HEARTBEATS
+		else if (rr->type == TLS1_RT_HEARTBEAT)
+			{
+			tls1_process_heartbeat(s);
+
+			/* Exit and notify application to read again */
+			rr->length = 0;
+			s->rwstate=SSL_READING;
+			BIO_clear_retry_flags(SSL_get_rbio(s));
+			BIO_set_retry_read(SSL_get_rbio(s));
+			return(-1);
+			}
+#endif
 
 		if (dest_maxlen > 0)
 			{
@@ -1017,7 +1182,25 @@ start:
 		 * now try again to obtain the (application) data we were asked for */
 		goto start;
 		}
-
+	/* If we are a server and get a client hello when renegotiation isn't
+	 * allowed send back a no renegotiation alert and carry on.
+	 * WARNING: experimental code, needs reviewing (steve)
+	 */
+	if (s->server &&
+		SSL_is_init_finished(s) &&
+    		!s->s3->send_connection_binding &&
+		(s->version > SSL3_VERSION) &&
+		(s->s3->handshake_fragment_len >= 4) &&
+		(s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
+		(s->session != NULL) && (s->session->cipher != NULL) &&
+		!(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
+		
+		{
+		/*s->s3->handshake_fragment_len = 0;*/
+		rr->length = 0;
+		ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
+		goto start;
+		}
 	if (s->s3->alert_fragment_len >= 2)
 		{
 		int alert_level = s->s3->alert_fragment[0];
@@ -1047,6 +1230,25 @@ start:
 				s->shutdown |= SSL_RECEIVED_SHUTDOWN;
 				return(0);
 				}
+			/* This is a warning but we receive it if we requested
+			 * renegotiation and the peer denied it. Terminate with
+			 * a fatal alert because if application tried to
+			 * renegotiatie it presumably had a good reason and
+			 * expects it to succeed.
+			 *
+			 * In future we might have a renegotiation where we
+			 * don't care if the peer refused it where we carry on.
+			 */
+			else if (alert_descr == SSL_AD_NO_RENEGOTIATION)
+				{
+				al = SSL_AD_HANDSHAKE_FAILURE;
+				SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION);
+				goto f_err;
+				}
+#ifdef SSL_AD_MISSING_SRP_USERNAME
+			else if (alert_descr == SSL_AD_MISSING_SRP_USERNAME)
+				return(0);
+#endif
 			}
 		else if (alert_level == 2) /* fatal */
 			{
@@ -1125,6 +1327,7 @@ start:
 #else
 			s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
 #endif
+			s->renegotiate=1;
 			s->new_session=1;
 			}
 		i=s->handshake_func(s);
@@ -1158,8 +1361,10 @@ start:
 		{
 	default:
 #ifndef OPENSSL_NO_TLS
-		/* TLS just ignores unknown message types */
-		if (s->version == TLS1_VERSION)
+		/* TLS up to v1.1 just ignores unknown message types:
+		 * TLS v1.2 give an unexpected message alert.
+		 */
+		if (s->version >= TLS1_VERSION && s->version <= TLS1_1_VERSION)
 			{
 			rr->length = 0;
 			goto start;
@@ -1229,6 +1434,13 @@ int ssl3_do_change_cipher_spec(SSL *s)
 
 	if (s->s3->tmp.key_block == NULL)
 		{
+		if (s->session == NULL) 
+			{
+			/* might happen if dtls1_read_bytes() calls this */
+			SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY);
+			return (0);
+			}
+
 		s->session->cipher=s->s3->tmp.new_cipher;
 		if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
 		}
@@ -1251,20 +1463,18 @@ int ssl3_do_change_cipher_spec(SSL *s)
 		}
 
 	s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
-		&(s->s3->finish_dgst1),
-		&(s->s3->finish_dgst2),
 		sender,slen,s->s3->tmp.peer_finish_md);
 
 	return(1);
 	}
 
-void ssl3_send_alert(SSL *s, int level, int desc)
+int ssl3_send_alert(SSL *s, int level, int desc)
 	{
 	/* Map tls/ssl alert value to correct one */
 	desc=s->method->ssl3_enc->alert_value(desc);
 	if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
 		desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */
-	if (desc < 0) return;
+	if (desc < 0) return -1;
 	/* If a fatal one, remove from cache */
 	if ((level == 2) && (s->session != NULL))
 		SSL_CTX_remove_session(s->ctx,s->session);
@@ -1273,9 +1483,10 @@ void ssl3_send_alert(SSL *s, int level, int desc)
 	s->s3->send_alert[0]=level;
 	s->s3->send_alert[1]=desc;
 	if (s->s3->wbuf.left == 0) /* data still being written out? */
-		s->method->ssl_dispatch_alert(s);
+		return s->method->ssl_dispatch_alert(s);
 	/* else data is still being written out, we will get written
 	 * some time in the future */
+	return -1;
 	}
 
 int ssl3_dispatch_alert(SSL *s)