Submitted by: Robin Seggelmann <seggelmann@fh-muenster.de>
Reviewed by: steve

Fix DTLS bug which prevents manual MTU setting
This commit is contained in:
Dr. Stephen Henson 2011-09-23 13:35:19 +00:00
parent 0b96f60a56
commit 8f0968850b
4 changed files with 15 additions and 6 deletions

View file

@ -158,7 +158,6 @@ static unsigned char bitmask_end_values[] = {0xff, 0x01, 0x03, 0x07, 0x0f, 0x1
/* XDTLS: figure out the right values */ /* XDTLS: figure out the right values */
static unsigned int g_probable_mtu[] = {1500 - 28, 512 - 28, 256 - 28}; static unsigned int g_probable_mtu[] = {1500 - 28, 512 - 28, 256 - 28};
static unsigned int dtls1_min_mtu(void);
static unsigned int dtls1_guess_mtu(unsigned int curr_mtu); static unsigned int dtls1_guess_mtu(unsigned int curr_mtu);
static void dtls1_fix_message_header(SSL *s, unsigned long frag_off, static void dtls1_fix_message_header(SSL *s, unsigned long frag_off,
unsigned long frag_len); unsigned long frag_len);
@ -264,11 +263,10 @@ int dtls1_do_write(SSL *s, int type)
return ret; return ret;
mtu = s->d1->mtu - (DTLS1_HM_HEADER_LENGTH + DTLS1_RT_HEADER_LENGTH); mtu = s->d1->mtu - (DTLS1_HM_HEADER_LENGTH + DTLS1_RT_HEADER_LENGTH);
} }
OPENSSL_assert(mtu > 0); /* should have something reasonable now */
#endif #endif
OPENSSL_assert(s->d1->mtu >= dtls1_min_mtu()); /* should have something reasonable now */
if ( s->init_off == 0 && type == SSL3_RT_HANDSHAKE) if ( s->init_off == 0 && type == SSL3_RT_HANDSHAKE)
OPENSSL_assert(s->init_num == OPENSSL_assert(s->init_num ==
(int)s->d1->w_msg_hdr.msg_len + DTLS1_HM_HEADER_LENGTH); (int)s->d1->w_msg_hdr.msg_len + DTLS1_HM_HEADER_LENGTH);
@ -1367,7 +1365,7 @@ dtls1_write_message_header(SSL *s, unsigned char *p)
return p; return p;
} }
static unsigned int unsigned int
dtls1_min_mtu(void) dtls1_min_mtu(void)
{ {
return (g_probable_mtu[(sizeof(g_probable_mtu) / return (g_probable_mtu[(sizeof(g_probable_mtu) /

View file

@ -204,7 +204,8 @@ void dtls1_clear(SSL *s)
pqueue buffered_messages; pqueue buffered_messages;
pqueue sent_messages; pqueue sent_messages;
pqueue buffered_app_data; pqueue buffered_app_data;
unsigned int mtu;
if (s->d1) if (s->d1)
{ {
unprocessed_rcds = s->d1->unprocessed_rcds.q; unprocessed_rcds = s->d1->unprocessed_rcds.q;
@ -212,6 +213,7 @@ void dtls1_clear(SSL *s)
buffered_messages = s->d1->buffered_messages; buffered_messages = s->d1->buffered_messages;
sent_messages = s->d1->sent_messages; sent_messages = s->d1->sent_messages;
buffered_app_data = s->d1->buffered_app_data.q; buffered_app_data = s->d1->buffered_app_data.q;
mtu = s->d1->mtu;
dtls1_clear_queues(s); dtls1_clear_queues(s);
@ -222,6 +224,11 @@ void dtls1_clear(SSL *s)
s->d1->cookie_len = sizeof(s->d1->cookie); s->d1->cookie_len = sizeof(s->d1->cookie);
} }
if (SSL_get_options(s) & SSL_OP_NO_QUERY_MTU)
{
s->d1->mtu = mtu;
}
s->d1->unprocessed_rcds.q = unprocessed_rcds; s->d1->unprocessed_rcds.q = unprocessed_rcds;
s->d1->processed_rcds.q = processed_rcds; s->d1->processed_rcds.q = processed_rcds;
s->d1->buffered_messages = buffered_messages; s->d1->buffered_messages = buffered_messages;

View file

@ -1054,6 +1054,9 @@ long SSL_ctrl(SSL *s,int cmd,long larg,void *parg)
s->max_cert_list=larg; s->max_cert_list=larg;
return(l); return(l);
case SSL_CTRL_SET_MTU: case SSL_CTRL_SET_MTU:
if (larg < dtls1_min_mtu())
return 0;
if (SSL_version(s) == DTLS1_VERSION || if (SSL_version(s) == DTLS1_VERSION ||
SSL_version(s) == DTLS1_BAD_VER) SSL_version(s) == DTLS1_BAD_VER)
{ {

View file

@ -950,6 +950,7 @@ void dtls1_stop_timer(SSL *s);
int dtls1_is_timer_expired(SSL *s); int dtls1_is_timer_expired(SSL *s);
void dtls1_double_timeout(SSL *s); void dtls1_double_timeout(SSL *s);
int dtls1_send_newsession_ticket(SSL *s); int dtls1_send_newsession_ticket(SSL *s);
unsigned int dtls1_min_mtu(void);
/* some client-only functions */ /* some client-only functions */
int ssl3_client_hello(SSL *s); int ssl3_client_hello(SSL *s);