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authormarha <marha@users.sourceforge.net>2010-03-30 12:36:28 +0000
committermarha <marha@users.sourceforge.net>2010-03-30 12:36:28 +0000
commitff48c0d9098080b51ea12710029135916d117806 (patch)
tree96e6af9caf170ba21a1027b24e306a07e27d7b75 /openssl/ssl/d1_both.c
parentbb731f5ac92655c4860a41fa818a7a63005f8369 (diff)
downloadvcxsrv-ff48c0d9098080b51ea12710029135916d117806.tar.gz
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svn merge -r514:HEAD ^/branches/released .
Diffstat (limited to 'openssl/ssl/d1_both.c')
-rw-r--r--openssl/ssl/d1_both.c326
1 files changed, 201 insertions, 125 deletions
diff --git a/openssl/ssl/d1_both.c b/openssl/ssl/d1_both.c
index 15a201a25..0242f1e4d 100644
--- a/openssl/ssl/d1_both.c
+++ b/openssl/ssl/d1_both.c
@@ -136,7 +136,6 @@ static unsigned char *dtls1_write_message_header(SSL *s,
static void dtls1_set_message_header_int(SSL *s, unsigned char mt,
unsigned long len, unsigned short seq_num, unsigned long frag_off,
unsigned long frag_len);
-static int dtls1_retransmit_buffered_messages(SSL *s);
static long dtls1_get_message_fragment(SSL *s, int st1, int stn,
long max, int *ok);
@@ -178,7 +177,7 @@ int dtls1_do_write(SSL *s, int type)
{
int ret;
int curr_mtu;
- unsigned int len, frag_off;
+ unsigned int len, frag_off, mac_size, blocksize;
/* AHA! Figure out the MTU, and stick to the right size */
if ( ! (SSL_get_options(s) & SSL_OP_NO_QUERY_MTU))
@@ -226,11 +225,22 @@ int dtls1_do_write(SSL *s, int type)
OPENSSL_assert(s->init_num ==
(int)s->d1->w_msg_hdr.msg_len + DTLS1_HM_HEADER_LENGTH);
+ if (s->write_hash)
+ mac_size = EVP_MD_CTX_size(s->write_hash);
+ else
+ mac_size = 0;
+
+ if (s->enc_write_ctx &&
+ (EVP_CIPHER_mode( s->enc_write_ctx->cipher) & EVP_CIPH_CBC_MODE))
+ blocksize = 2 * EVP_CIPHER_block_size(s->enc_write_ctx->cipher);
+ else
+ blocksize = 0;
+
frag_off = 0;
while( s->init_num)
{
curr_mtu = s->d1->mtu - BIO_wpending(SSL_get_wbio(s)) -
- DTLS1_RT_HEADER_LENGTH;
+ DTLS1_RT_HEADER_LENGTH - mac_size - blocksize;
if ( curr_mtu <= DTLS1_HM_HEADER_LENGTH)
{
@@ -238,7 +248,8 @@ int dtls1_do_write(SSL *s, int type)
ret = BIO_flush(SSL_get_wbio(s));
if ( ret <= 0)
return ret;
- curr_mtu = s->d1->mtu - DTLS1_RT_HEADER_LENGTH;
+ curr_mtu = s->d1->mtu - DTLS1_RT_HEADER_LENGTH -
+ mac_size - blocksize;
}
if ( s->init_num > curr_mtu)
@@ -280,7 +291,7 @@ int dtls1_do_write(SSL *s, int type)
* retransmit
*/
if ( BIO_ctrl(SSL_get_wbio(s),
- BIO_CTRL_DGRAM_MTU_EXCEEDED, 0, NULL))
+ BIO_CTRL_DGRAM_MTU_EXCEEDED, 0, NULL) > 0 )
s->d1->mtu = BIO_ctrl(SSL_get_wbio(s),
BIO_CTRL_DGRAM_QUERY_MTU, 0, NULL);
else
@@ -301,7 +312,7 @@ int dtls1_do_write(SSL *s, int type)
const struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr;
int xlen;
- if (frag_off == 0 && s->client_version != DTLS1_BAD_VER)
+ if (frag_off == 0 && s->version != DTLS1_BAD_VER)
{
/* reconstruct message header is if it
* is being sent in single fragment */
@@ -408,9 +419,10 @@ long dtls1_get_message(SSL *s, int st1, int stn, int mt, long max, int *ok)
s2n (msg_hdr->seq,p);
l2n3(0,p);
l2n3(msg_len,p);
- if (s->client_version != DTLS1_BAD_VER)
- p -= DTLS1_HM_HEADER_LENGTH,
+ if (s->version != DTLS1_BAD_VER) {
+ p -= DTLS1_HM_HEADER_LENGTH;
msg_len += DTLS1_HM_HEADER_LENGTH;
+ }
ssl3_finish_mac(s, p, msg_len);
if (s->msg_callback)
@@ -474,7 +486,7 @@ static int dtls1_preprocess_fragment(SSL *s,struct hm_header_st *msg_hdr,int max
{
/* msg_len is limited to 2^24, but is effectively checked
* against max above */
- if (!BUF_MEM_grow_clean(s->init_buf,(int)msg_len+DTLS1_HM_HEADER_LENGTH))
+ if (!BUF_MEM_grow_clean(s->init_buf,msg_len+DTLS1_HM_HEADER_LENGTH))
{
SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT,ERR_R_BUF_LIB);
return SSL_AD_INTERNAL_ERROR;
@@ -519,6 +531,7 @@ dtls1_retrieve_buffered_fragment(SSL *s, long max, int *ok)
if ( s->d1->handshake_read_seq == frag->msg_header.seq)
{
+ unsigned long frag_len = frag->msg_header.frag_len;
pqueue_pop(s->d1->buffered_messages);
al=dtls1_preprocess_fragment(s,&frag->msg_header,max);
@@ -536,7 +549,7 @@ dtls1_retrieve_buffered_fragment(SSL *s, long max, int *ok)
if (al==0)
{
*ok = 1;
- return frag->msg_header.frag_len;
+ return frag_len;
}
ssl3_send_alert(s,SSL3_AL_FATAL,al);
@@ -555,13 +568,26 @@ dtls1_process_out_of_seq_message(SSL *s, struct hm_header_st* msg_hdr, int *ok)
int i=-1;
hm_fragment *frag = NULL;
pitem *item = NULL;
- PQ_64BIT seq64;
+ unsigned char seq64be[8];
unsigned long frag_len = msg_hdr->frag_len;
if ((msg_hdr->frag_off+frag_len) > msg_hdr->msg_len)
goto err;
- if (msg_hdr->seq <= s->d1->handshake_read_seq)
+ /* Try to find item in queue, to prevent duplicate entries */
+ memset(seq64be,0,sizeof(seq64be));
+ seq64be[6] = (unsigned char) (msg_hdr->seq>>8);
+ seq64be[7] = (unsigned char) msg_hdr->seq;
+ item = pqueue_find(s->d1->buffered_messages, seq64be);
+
+ /* Discard the message if sequence number was already there, is
+ * too far in the future, already in the queue or if we received
+ * a FINISHED before the SERVER_HELLO, which then must be a stale
+ * retransmit.
+ */
+ if (msg_hdr->seq <= s->d1->handshake_read_seq ||
+ msg_hdr->seq > s->d1->handshake_read_seq + 10 || item != NULL ||
+ (s->d1->handshake_read_seq == 0 && msg_hdr->type == SSL3_MT_FINISHED))
{
unsigned char devnull [256];
@@ -575,30 +601,31 @@ dtls1_process_out_of_seq_message(SSL *s, struct hm_header_st* msg_hdr, int *ok)
}
}
- frag = dtls1_hm_fragment_new(frag_len);
- if ( frag == NULL)
- goto err;
-
- memcpy(&(frag->msg_header), msg_hdr, sizeof(*msg_hdr));
-
if (frag_len)
{
+ frag = dtls1_hm_fragment_new(frag_len);
+ if ( frag == NULL)
+ goto err;
+
+ memcpy(&(frag->msg_header), msg_hdr, sizeof(*msg_hdr));
+
/* read the body of the fragment (header has already been read */
i = s->method->ssl_read_bytes(s,SSL3_RT_HANDSHAKE,
frag->fragment,frag_len,0);
if (i<=0 || (unsigned long)i!=frag_len)
goto err;
- }
- pq_64bit_init(&seq64);
- pq_64bit_assign_word(&seq64, msg_hdr->seq);
+ memset(seq64be,0,sizeof(seq64be));
+ seq64be[6] = (unsigned char)(msg_hdr->seq>>8);
+ seq64be[7] = (unsigned char)(msg_hdr->seq);
- item = pitem_new(seq64, frag);
- pq_64bit_free(&seq64);
- if ( item == NULL)
- goto err;
+ item = pitem_new(seq64be, frag);
+ if ( item == NULL)
+ goto err;
+
+ pqueue_insert(s->d1->buffered_messages, item);
+ }
- pqueue_insert(s->d1->buffered_messages, item);
return DTLS1_HM_FRAGMENT_RETRY;
err:
@@ -731,14 +758,30 @@ int dtls1_send_finished(SSL *s, int a, int b, const char *sender, int slen)
p= &(d[DTLS1_HM_HEADER_LENGTH]);
i=s->method->ssl3_enc->final_finish_mac(s,
- &(s->s3->finish_dgst1),
- &(s->s3->finish_dgst2),
sender,slen,s->s3->tmp.finish_md);
s->s3->tmp.finish_md_len = i;
memcpy(p, s->s3->tmp.finish_md, i);
p+=i;
l=i;
+ /* Copy the finished so we can use it for
+ * renegotiation checks
+ */
+ if(s->type == SSL_ST_CONNECT)
+ {
+ OPENSSL_assert(i <= EVP_MAX_MD_SIZE);
+ memcpy(s->s3->previous_client_finished,
+ s->s3->tmp.finish_md, i);
+ s->s3->previous_client_finished_len=i;
+ }
+ else
+ {
+ OPENSSL_assert(i <= EVP_MAX_MD_SIZE);
+ memcpy(s->s3->previous_server_finished,
+ s->s3->tmp.finish_md, i);
+ s->s3->previous_server_finished_len=i;
+ }
+
#ifdef OPENSSL_SYS_WIN16
/* MSVC 1.5 does not clear the top bytes of the word unless
* I do this.
@@ -779,12 +822,11 @@ int dtls1_send_change_cipher_spec(SSL *s, int a, int b)
s->d1->handshake_write_seq = s->d1->next_handshake_write_seq;
s->init_num=DTLS1_CCS_HEADER_LENGTH;
- if (s->client_version == DTLS1_BAD_VER)
- {
+ if (s->version == DTLS1_BAD_VER) {
s->d1->next_handshake_write_seq++;
s2n(s->d1->handshake_write_seq,p);
s->init_num+=2;
- }
+ }
s->init_off=0;
@@ -801,14 +843,30 @@ int dtls1_send_change_cipher_spec(SSL *s, int a, int b)
return(dtls1_do_write(s,SSL3_RT_CHANGE_CIPHER_SPEC));
}
+static int dtls1_add_cert_to_buf(BUF_MEM *buf, unsigned long *l, X509 *x)
+ {
+ int n;
+ unsigned char *p;
+
+ n=i2d_X509(x,NULL);
+ if (!BUF_MEM_grow_clean(buf,(int)(n+(*l)+3)))
+ {
+ SSLerr(SSL_F_DTLS1_ADD_CERT_TO_BUF,ERR_R_BUF_LIB);
+ return 0;
+ }
+ p=(unsigned char *)&(buf->data[*l]);
+ l2n3(n,p);
+ i2d_X509(x,&p);
+ *l+=n+3;
+
+ return 1;
+ }
unsigned long dtls1_output_cert_chain(SSL *s, X509 *x)
{
unsigned char *p;
- int n,i;
+ int i;
unsigned long l= 3 + DTLS1_HM_HEADER_LENGTH;
BUF_MEM *buf;
- X509_STORE_CTX xs_ctx;
- X509_OBJECT obj;
/* TLSv1 sends a chain with nothing in it, instead of an alert */
buf=s->init_buf;
@@ -819,54 +877,35 @@ unsigned long dtls1_output_cert_chain(SSL *s, X509 *x)
}
if (x != NULL)
{
- if(!X509_STORE_CTX_init(&xs_ctx,s->ctx->cert_store,NULL,NULL))
- {
- SSLerr(SSL_F_DTLS1_OUTPUT_CERT_CHAIN,ERR_R_X509_LIB);
- return(0);
- }
-
- for (;;)
- {
- n=i2d_X509(x,NULL);
- if (!BUF_MEM_grow_clean(buf,(int)(n+l+3)))
- {
- SSLerr(SSL_F_DTLS1_OUTPUT_CERT_CHAIN,ERR_R_BUF_LIB);
- return(0);
- }
- p=(unsigned char *)&(buf->data[l]);
- l2n3(n,p);
- i2d_X509(x,&p);
- l+=n+3;
- if (X509_NAME_cmp(X509_get_subject_name(x),
- X509_get_issuer_name(x)) == 0) break;
-
- i=X509_STORE_get_by_subject(&xs_ctx,X509_LU_X509,
- X509_get_issuer_name(x),&obj);
- if (i <= 0) break;
- x=obj.data.x509;
- /* Count is one too high since the X509_STORE_get uped the
- * ref count */
- X509_free(x);
- }
-
- X509_STORE_CTX_cleanup(&xs_ctx);
- }
-
- /* Thawte special :-) */
- if (s->ctx->extra_certs != NULL)
+ X509_STORE_CTX xs_ctx;
+
+ if (!X509_STORE_CTX_init(&xs_ctx,s->ctx->cert_store,x,NULL))
+ {
+ SSLerr(SSL_F_DTLS1_OUTPUT_CERT_CHAIN,ERR_R_X509_LIB);
+ return(0);
+ }
+
+ X509_verify_cert(&xs_ctx);
+ /* Don't leave errors in the queue */
+ ERR_clear_error();
+ for (i=0; i < sk_X509_num(xs_ctx.chain); i++)
+ {
+ x = sk_X509_value(xs_ctx.chain, i);
+
+ if (!dtls1_add_cert_to_buf(buf, &l, x))
+ {
+ X509_STORE_CTX_cleanup(&xs_ctx);
+ return 0;
+ }
+ }
+ X509_STORE_CTX_cleanup(&xs_ctx);
+ }
+ /* Thawte special :-) */
for (i=0; i<sk_X509_num(s->ctx->extra_certs); i++)
{
x=sk_X509_value(s->ctx->extra_certs,i);
- n=i2d_X509(x,NULL);
- if (!BUF_MEM_grow_clean(buf,(int)(n+l+3)))
- {
- SSLerr(SSL_F_DTLS1_OUTPUT_CERT_CHAIN,ERR_R_BUF_LIB);
- return(0);
- }
- p=(unsigned char *)&(buf->data[l]);
- l2n3(n,p);
- i2d_X509(x,&p);
- l+=n+3;
+ if (!dtls1_add_cert_to_buf(buf, &l, x))
+ return 0;
}
l-= (3 + DTLS1_HM_HEADER_LENGTH);
@@ -883,18 +922,13 @@ unsigned long dtls1_output_cert_chain(SSL *s, X509 *x)
int dtls1_read_failed(SSL *s, int code)
{
- DTLS1_STATE *state;
- BIO *bio;
- int send_alert = 0;
-
if ( code > 0)
{
fprintf( stderr, "invalid state reached %s:%d", __FILE__, __LINE__);
return 1;
}
- bio = SSL_get_rbio(s);
- if ( ! BIO_dgram_recv_timedout(bio))
+ if (!dtls1_is_timer_expired(s))
{
/* not a timeout, none of our business,
let higher layers handle this. in fact it's probably an error */
@@ -907,23 +941,6 @@ int dtls1_read_failed(SSL *s, int code)
return code;
}
- state = s->d1;
- state->timeout.num_alerts++;
- if ( state->timeout.num_alerts > DTLS1_TMO_ALERT_COUNT)
- {
- /* fail the connection, enough alerts have been sent */
- SSLerr(SSL_F_DTLS1_READ_FAILED,SSL_R_READ_TIMEOUT_EXPIRED);
- return 0;
- }
-
- state->timeout.read_timeouts++;
- if ( state->timeout.read_timeouts > DTLS1_TMO_READ_COUNT)
- {
- send_alert = 1;
- state->timeout.read_timeouts = 1;
- }
-
-
#if 0 /* for now, each alert contains only one record number */
item = pqueue_peek(state->rcvd_records);
if ( item )
@@ -934,16 +951,29 @@ int dtls1_read_failed(SSL *s, int code)
#endif
#if 0 /* no more alert sending, just retransmit the last set of messages */
- if ( send_alert)
- ssl3_send_alert(s,SSL3_AL_WARNING,
- DTLS1_AD_MISSING_HANDSHAKE_MESSAGE);
+ if ( state->timeout.read_timeouts >= DTLS1_TMO_READ_COUNT)
+ ssl3_send_alert(s,SSL3_AL_WARNING,
+ DTLS1_AD_MISSING_HANDSHAKE_MESSAGE);
#endif
- return dtls1_retransmit_buffered_messages(s) ;
+ return dtls1_handle_timeout(s);
}
+int
+dtls1_get_queue_priority(unsigned short seq, int is_ccs)
+ {
+ /* The index of the retransmission queue actually is the message sequence number,
+ * since the queue only contains messages of a single handshake. However, the
+ * ChangeCipherSpec has no message sequence number and so using only the sequence
+ * will result in the CCS and Finished having the same index. To prevent this,
+ * the sequence number is multiplied by 2. In case of a CCS 1 is subtracted.
+ * This does not only differ CSS and Finished, it also maintains the order of the
+ * index (important for priority queues) and fits in the unsigned short variable.
+ */
+ return seq * 2 - is_ccs;
+ }
-static int
+int
dtls1_retransmit_buffered_messages(SSL *s)
{
pqueue sent = s->d1->sent_messages;
@@ -957,8 +987,9 @@ dtls1_retransmit_buffered_messages(SSL *s)
for ( item = pqueue_next(&iter); item != NULL; item = pqueue_next(&iter))
{
frag = (hm_fragment *)item->data;
- if ( dtls1_retransmit_message(s, frag->msg_header.seq, 0, &found) <= 0 &&
- found)
+ if ( dtls1_retransmit_message(s,
+ (unsigned short)dtls1_get_queue_priority(frag->msg_header.seq, frag->msg_header.is_ccs),
+ 0, &found) <= 0 && found)
{
fprintf(stderr, "dtls1_retransmit_message() failed\n");
return -1;
@@ -973,8 +1004,7 @@ dtls1_buffer_message(SSL *s, int is_ccs)
{
pitem *item;
hm_fragment *frag;
- PQ_64BIT seq64;
- unsigned int epoch = s->d1->w_epoch;
+ unsigned char seq64be[8];
/* this function is called immediately after a message has
* been serialized */
@@ -987,8 +1017,7 @@ dtls1_buffer_message(SSL *s, int is_ccs)
if ( is_ccs)
{
OPENSSL_assert(s->d1->w_msg_hdr.msg_len +
- DTLS1_CCS_HEADER_LENGTH <= (unsigned int)s->init_num);
- epoch++;
+ ((s->version==DTLS1_VERSION)?DTLS1_CCS_HEADER_LENGTH:3) == (unsigned int)s->init_num);
}
else
{
@@ -1003,11 +1032,20 @@ dtls1_buffer_message(SSL *s, int is_ccs)
frag->msg_header.frag_len = s->d1->w_msg_hdr.msg_len;
frag->msg_header.is_ccs = is_ccs;
- pq_64bit_init(&seq64);
- pq_64bit_assign_word(&seq64, epoch<<16 | frag->msg_header.seq);
-
- item = pitem_new(seq64, frag);
- pq_64bit_free(&seq64);
+ /* save current state*/
+ frag->msg_header.saved_retransmit_state.enc_write_ctx = s->enc_write_ctx;
+ frag->msg_header.saved_retransmit_state.write_hash = s->write_hash;
+ frag->msg_header.saved_retransmit_state.compress = s->compress;
+ frag->msg_header.saved_retransmit_state.session = s->session;
+ frag->msg_header.saved_retransmit_state.epoch = s->d1->w_epoch;
+
+ memset(seq64be,0,sizeof(seq64be));
+ seq64be[6] = (unsigned char)(dtls1_get_queue_priority(frag->msg_header.seq,
+ frag->msg_header.is_ccs)>>8);
+ seq64be[7] = (unsigned char)(dtls1_get_queue_priority(frag->msg_header.seq,
+ frag->msg_header.is_ccs));
+
+ item = pitem_new(seq64be, frag);
if ( item == NULL)
{
dtls1_hm_fragment_free(frag);
@@ -1033,7 +1071,9 @@ dtls1_retransmit_message(SSL *s, unsigned short seq, unsigned long frag_off,
pitem *item;
hm_fragment *frag ;
unsigned long header_length;
- PQ_64BIT seq64;
+ unsigned char seq64be[8];
+ struct dtls1_retransmit_state saved_state;
+ unsigned char save_write_sequence[8];
/*
OPENSSL_assert(s->init_num == 0);
@@ -1041,11 +1081,11 @@ dtls1_retransmit_message(SSL *s, unsigned short seq, unsigned long frag_off,
*/
/* XDTLS: the requested message ought to be found, otherwise error */
- pq_64bit_init(&seq64);
- pq_64bit_assign_word(&seq64, seq);
+ memset(seq64be,0,sizeof(seq64be));
+ seq64be[6] = (unsigned char)(seq>>8);
+ seq64be[7] = (unsigned char)seq;
- item = pqueue_find(s->d1->sent_messages, seq64);
- pq_64bit_free(&seq64);
+ item = pqueue_find(s->d1->sent_messages, seq64be);
if ( item == NULL)
{
fprintf(stderr, "retransmit: message %d non-existant\n", seq);
@@ -1069,9 +1109,45 @@ dtls1_retransmit_message(SSL *s, unsigned short seq, unsigned long frag_off,
frag->msg_header.msg_len, frag->msg_header.seq, 0,
frag->msg_header.frag_len);
+ /* save current state */
+ saved_state.enc_write_ctx = s->enc_write_ctx;
+ saved_state.write_hash = s->write_hash;
+ saved_state.compress = s->compress;
+ saved_state.session = s->session;
+ saved_state.epoch = s->d1->w_epoch;
+ saved_state.epoch = s->d1->w_epoch;
+
s->d1->retransmitting = 1;
+
+ /* restore state in which the message was originally sent */
+ s->enc_write_ctx = frag->msg_header.saved_retransmit_state.enc_write_ctx;
+ s->write_hash = frag->msg_header.saved_retransmit_state.write_hash;
+ s->compress = frag->msg_header.saved_retransmit_state.compress;
+ s->session = frag->msg_header.saved_retransmit_state.session;
+ s->d1->w_epoch = frag->msg_header.saved_retransmit_state.epoch;
+
+ if (frag->msg_header.saved_retransmit_state.epoch == saved_state.epoch - 1)
+ {
+ memcpy(save_write_sequence, s->s3->write_sequence, sizeof(s->s3->write_sequence));
+ memcpy(s->s3->write_sequence, s->d1->last_write_sequence, sizeof(s->s3->write_sequence));
+ }
+
ret = dtls1_do_write(s, frag->msg_header.is_ccs ?
- SSL3_RT_CHANGE_CIPHER_SPEC : SSL3_RT_HANDSHAKE);
+ SSL3_RT_CHANGE_CIPHER_SPEC : SSL3_RT_HANDSHAKE);
+
+ /* restore current state */
+ s->enc_write_ctx = saved_state.enc_write_ctx;
+ s->write_hash = saved_state.write_hash;
+ s->compress = saved_state.compress;
+ s->session = saved_state.session;
+ s->d1->w_epoch = saved_state.epoch;
+
+ if (frag->msg_header.saved_retransmit_state.epoch == saved_state.epoch - 1)
+ {
+ memcpy(s->d1->last_write_sequence, s->s3->write_sequence, sizeof(s->s3->write_sequence));
+ memcpy(s->s3->write_sequence, save_write_sequence, sizeof(s->s3->write_sequence));
+ }
+
s->d1->retransmitting = 0;
(void)BIO_flush(SSL_get_wbio(s));
@@ -1160,7 +1236,7 @@ dtls1_min_mtu(void)
static unsigned int
dtls1_guess_mtu(unsigned int curr_mtu)
{
- size_t i;
+ unsigned int i;
if ( curr_mtu == 0 )
return g_probable_mtu[0] ;