There are a number of instances throughout the code where the constant 28 is
[openssl.git] / crypto / bio / bss_dgram.c
index 07d012a46d4be9fdf563083f082609a9e4e511b1..bf1e39b5c0b4009dd7bb26ffbe3b1a24984cd893 100644 (file)
@@ -57,7 +57,6 @@
  *
  */
 
-#ifndef OPENSSL_NO_DGRAM
 
 #include <stdio.h>
 #include <errno.h>
 #include "cryptlib.h"
 
 #include <openssl/bio.h>
+#ifndef OPENSSL_NO_DGRAM
 
-#if defined(OPENSSL_SYS_WIN32) || defined(OPENSSL_SYS_VMS)
+#if defined(OPENSSL_SYS_VMS)
 #include <sys/timeb.h>
 #endif
 
-#ifdef OPENSSL_SYS_LINUX
+#ifndef OPENSSL_NO_SCTP
+#include <netinet/sctp.h>
+#include <fcntl.h>
+#define OPENSSL_SCTP_DATA_CHUNK_TYPE            0x00
+#define OPENSSL_SCTP_FORWARD_CUM_TSN_CHUNK_TYPE 0xc0
+#endif
+
+#if defined(OPENSSL_SYS_LINUX) && !defined(IP_MTU)
 #define IP_MTU      14 /* linux is lame */
 #endif
 
+#if OPENSSL_USE_IPV6 && !defined(IPPROTO_IPV6)
+#define IPPROTO_IPV6 41 /* windows is lame */
+#endif
+
+#if defined(__FreeBSD__) && defined(IN6_IS_ADDR_V4MAPPED)
+/* Standard definition causes type-punning problems. */
+#undef IN6_IS_ADDR_V4MAPPED
+#define s6_addr32 __u6_addr.__u6_addr32
+#define IN6_IS_ADDR_V4MAPPED(a)               \
+        (((a)->s6_addr32[0] == 0) &&          \
+         ((a)->s6_addr32[1] == 0) &&          \
+         ((a)->s6_addr32[2] == htonl(0x0000ffff)))
+#endif
+
 #ifdef WATT32
 #define sock_write SockWrite  /* Watt-32 uses same names */
 #define sock_read  SockRead
@@ -88,6 +109,18 @@ static int dgram_new(BIO *h);
 static int dgram_free(BIO *data);
 static int dgram_clear(BIO *bio);
 
+#ifndef OPENSSL_NO_SCTP
+static int dgram_sctp_write(BIO *h, const char *buf, int num);
+static int dgram_sctp_read(BIO *h, char *buf, int size);
+static int dgram_sctp_puts(BIO *h, const char *str);
+static long dgram_sctp_ctrl(BIO *h, int cmd, long arg1, void *arg2);
+static int dgram_sctp_new(BIO *h);
+static int dgram_sctp_free(BIO *data);
+#ifdef SCTP_AUTHENTICATION_EVENT
+static void dgram_sctp_handle_auth_free_key_event(BIO *b, union sctp_notification *snp);
+#endif
+#endif
+
 static int BIO_dgram_should_retry(int s);
 
 static void get_current_time(struct timeval *t);
@@ -106,6 +139,22 @@ static BIO_METHOD methods_dgramp=
        NULL,
        };
 
+#ifndef OPENSSL_NO_SCTP
+static BIO_METHOD methods_dgramp_sctp=
+       {
+       BIO_TYPE_DGRAM_SCTP,
+       "datagram sctp socket",
+       dgram_sctp_write,
+       dgram_sctp_read,
+       dgram_sctp_puts,
+       NULL, /* dgram_gets, */
+       dgram_sctp_ctrl,
+       dgram_sctp_new,
+       dgram_sctp_free,
+       NULL,
+       };
+#endif
+
 typedef struct bio_dgram_data_st
        {
        union {
@@ -122,6 +171,40 @@ typedef struct bio_dgram_data_st
        struct timeval socket_timeout;
        } bio_dgram_data;
 
+#ifndef OPENSSL_NO_SCTP
+typedef struct bio_dgram_sctp_save_message_st
+       {
+        BIO *bio;
+        char *data;
+        int length;
+       } bio_dgram_sctp_save_message;
+
+typedef struct bio_dgram_sctp_data_st
+       {
+       union {
+               struct sockaddr sa;
+               struct sockaddr_in sa_in;
+#if OPENSSL_USE_IPV6
+               struct sockaddr_in6 sa_in6;
+#endif
+       } peer;
+       unsigned int connected;
+       unsigned int _errno;
+       unsigned int mtu;
+       struct bio_dgram_sctp_sndinfo sndinfo;
+       struct bio_dgram_sctp_rcvinfo rcvinfo;
+       struct bio_dgram_sctp_prinfo prinfo;
+       void (*handle_notifications)(BIO *bio, void *context, void *buf);
+       void* notification_context;
+       int in_handshake;
+       int ccs_rcvd;
+       int ccs_sent;
+       int save_shutdown;
+       int peer_auth_tested;
+       bio_dgram_sctp_save_message saved_message;
+       } bio_dgram_sctp_data;
+#endif
+
 BIO_METHOD *BIO_s_datagram(void)
        {
        return(&methods_dgramp);
@@ -186,7 +269,7 @@ static void dgram_adjust_rcv_timeout(BIO *b)
        {
 #if defined(SO_RCVTIMEO)
        bio_dgram_data *data = (bio_dgram_data *)b->ptr;
-       int sz = sizeof(int);
+       union { size_t s; int i; } sz = {0};
 
        /* Is a timer active? */
        if (data->next_timeout.tv_sec > 0 || data->next_timeout.tv_usec > 0)
@@ -196,8 +279,10 @@ static void dgram_adjust_rcv_timeout(BIO *b)
                /* Read current socket timeout */
 #ifdef OPENSSL_SYS_WINDOWS
                int timeout;
+
+               sz.i = sizeof(timeout);
                if (getsockopt(b->num, SOL_SOCKET, SO_RCVTIMEO,
-                                          (void*)&timeout, &sz) < 0)
+                                          (void*)&timeout, &sz.i) < 0)
                        { perror("getsockopt"); }
                else
                        {
@@ -205,9 +290,12 @@ static void dgram_adjust_rcv_timeout(BIO *b)
                        data->socket_timeout.tv_usec = (timeout % 1000) * 1000;
                        }
 #else
+               sz.i = sizeof(data->socket_timeout);
                if ( getsockopt(b->num, SOL_SOCKET, SO_RCVTIMEO, 
                                                &(data->socket_timeout), (void *)&sz) < 0)
                        { perror("getsockopt"); }
+               else if (sizeof(sz.s)!=sizeof(sz.i) && sz.i==0)
+                       OPENSSL_assert(sz.s<=sizeof(data->socket_timeout));
 #endif
 
                /* Get current time */
@@ -308,7 +396,6 @@ static int dgram_read(BIO *b, char *out, int outl)
                        OPENSSL_assert(sa.len.s<=sizeof(sa.peer));
                        sa.len.i = (int)sa.len.s;
                        }
-               dgram_reset_rcv_timeout(b);
 
                if ( ! data->connected  && ret >= 0)
                        BIO_ctrl(b, BIO_CTRL_DGRAM_SET_PEER, 0, &sa.peer);
@@ -322,6 +409,8 @@ static int dgram_read(BIO *b, char *out, int outl)
                                data->_errno = get_last_socket_error();
                                }
                        }
+
+               dgram_reset_rcv_timeout(b);
                }
        return(ret);
        }
@@ -369,17 +458,46 @@ static int dgram_write(BIO *b, const char *in, int inl)
        return(ret);
        }
 
+static long dgram_get_mtu_overhead(bio_dgram_data *data)
+       {
+       long ret;
+
+       switch (data->peer.sa.sa_family)
+               {
+               case AF_INET:
+                       /* Assume this is UDP - 20 bytes for IP, 8 bytes for UDP */
+                       ret = 28;
+                       break;
+#if OPENSSL_USE_IPV6
+               case AF_INET6:
+#ifdef IN6_IS_ADDR_V4MAPPED
+                       if (IN6_IS_ADDR_V4MAPPED(&data->peer.sa_in6.sin6_addr))
+                               /* Assume this is UDP - 20 bytes for IP, 8 bytes for UDP */
+                               ret = 28;
+                       else
+#endif
+                               /* Assume this is UDP - 40 bytes for IP, 8 bytes for UDP */
+                               ret = 48;
+                       break;
+#endif
+               default:
+                       /* We don't know. Go with the historical default */
+                       ret = 28;
+                       break;
+               }
+       return ret;
+       }
+
 static long dgram_ctrl(BIO *b, int cmd, long num, void *ptr)
        {
        long ret=1;
        int *ip;
        struct sockaddr *to = NULL;
        bio_dgram_data *data = NULL;
-#if defined(IP_MTU_DISCOVER) || defined(IP_MTU)
-       long sockopt_val = 0;
-       unsigned int sockopt_len = 0;
-#endif
-#ifdef OPENSSL_SYS_LINUX
+       int sockopt_val = 0;
+#if defined(OPENSSL_SYS_LINUX) && (defined(IP_MTU_DISCOVER) || defined(IP_MTU))
+       socklen_t sockopt_len;  /* assume that system supporting IP_MTU is
+                                * modern enough to define socklen_t */
        socklen_t addr_len;
        union   {
                struct sockaddr sa;
@@ -461,7 +579,7 @@ static long dgram_ctrl(BIO *b, int cmd, long num, void *ptr)
                break;
                /* (Linux)kernel sets DF bit on outgoing IP packets */
        case BIO_CTRL_DGRAM_MTU_DISCOVER:
-#ifdef OPENSSL_SYS_LINUX
+#if defined(OPENSSL_SYS_LINUX) && defined(IP_MTU_DISCOVER) && defined(IP_PMTUDISC_DO)
                addr_len = (socklen_t)sizeof(addr);
                memset((void *)&addr, 0, sizeof(addr));
                if (getsockname(b->num, &addr.sa, &addr_len) < 0)
@@ -469,7 +587,6 @@ static long dgram_ctrl(BIO *b, int cmd, long num, void *ptr)
                        ret = 0;
                        break;
                        }
-               sockopt_len = sizeof(sockopt_val);
                switch (addr.sa.sa_family)
                        {
                case AF_INET:
@@ -478,7 +595,7 @@ static long dgram_ctrl(BIO *b, int cmd, long num, void *ptr)
                                &sockopt_val, sizeof(sockopt_val))) < 0)
                                perror("setsockopt");
                        break;
-#if OPENSSL_USE_IPV6 && defined(IPV6_MTU_DISCOVER)
+#if OPENSSL_USE_IPV6 && defined(IPV6_MTU_DISCOVER) && defined(IPV6_PMTUDISC_DO)
                case AF_INET6:
                        sockopt_val = IPV6_PMTUDISC_DO;
                        if ((ret = setsockopt(b->num, IPPROTO_IPV6, IPV6_MTU_DISCOVER,
@@ -490,12 +607,12 @@ static long dgram_ctrl(BIO *b, int cmd, long num, void *ptr)
                        ret = -1;
                        break;
                        }
-               ret = -1;
 #else
-               break;
+               ret = -1;
 #endif
+               break;
        case BIO_CTRL_DGRAM_QUERY_MTU:
-#ifdef OPENSSL_SYS_LINUX
+#if defined(OPENSSL_SYS_LINUX) && defined(IP_MTU)
                addr_len = (socklen_t)sizeof(addr);
                memset((void *)&addr, 0, sizeof(addr));
                if (getsockname(b->num, &addr.sa, &addr_len) < 0)
@@ -546,6 +663,28 @@ static long dgram_ctrl(BIO *b, int cmd, long num, void *ptr)
                ret = 0;
 #endif
                break;
+       case BIO_CTRL_DGRAM_GET_FALLBACK_MTU:
+               ret = -dgram_get_mtu_overhead(data);
+               switch (data->peer.sa.sa_family)
+                       {
+                       case AF_INET:
+                               ret += 576;
+                               break;
+#if OPENSSL_USE_IPV6
+                       case AF_INET6:
+#ifdef IN6_IS_ADDR_V4MAPPED
+                               if (IN6_IS_ADDR_V4MAPPED(&data->peer.sa_in6.sin6_addr))
+                                       ret += 576;
+                               else
+#endif
+                                       ret += 1280;
+                               break;
+#endif
+                       default:
+                               ret += 576;
+                               break;
+                       }
+               break;
        case BIO_CTRL_DGRAM_GET_MTU:
                return data->mtu;
                break;
@@ -636,12 +775,15 @@ static long dgram_ctrl(BIO *b, int cmd, long num, void *ptr)
 #endif
                break;
        case BIO_CTRL_DGRAM_GET_RECV_TIMEOUT:
-#ifdef OPENSSL_SYS_WINDOWS
                {
-               int timeout, sz = sizeof(timeout);
+               union { size_t s; int i; } sz = {0};
+#ifdef OPENSSL_SYS_WINDOWS
+               int timeout;
                struct timeval *tv = (struct timeval *)ptr;
+
+               sz.i = sizeof(timeout);
                if (getsockopt(b->num, SOL_SOCKET, SO_RCVTIMEO,
-                       (void*)&timeout, &sz) < 0)
+                       (void*)&timeout, &sz.i) < 0)
                        { perror("getsockopt"); ret = -1; }
                else
                        {
@@ -649,12 +791,20 @@ static long dgram_ctrl(BIO *b, int cmd, long num, void *ptr)
                        tv->tv_usec = (timeout % 1000) * 1000;
                        ret = sizeof(*tv);
                        }
-               }
 #else
+               sz.i = sizeof(struct timeval);
                if ( getsockopt(b->num, SOL_SOCKET, SO_RCVTIMEO, 
-                       ptr, (void *)&ret) < 0)
+                       ptr, (void *)&sz) < 0)
                        { perror("getsockopt"); ret = -1; }
+               else if (sizeof(sz.s)!=sizeof(sz.i) && sz.i==0)
+                       {
+                       OPENSSL_assert(sz.s<=sizeof(struct timeval));
+                       ret = (int)sz.s;
+                       }
+               else
+                       ret = sz.i;
 #endif
+               }
                break;
 #endif
 #if defined(SO_SNDTIMEO)
@@ -674,12 +824,15 @@ static long dgram_ctrl(BIO *b, int cmd, long num, void *ptr)
 #endif
                break;
        case BIO_CTRL_DGRAM_GET_SEND_TIMEOUT:
-#ifdef OPENSSL_SYS_WINDOWS
                {
-               int timeout, sz = sizeof(timeout);
+               union { size_t s; int i; } sz = {0};
+#ifdef OPENSSL_SYS_WINDOWS
+               int timeout;
                struct timeval *tv = (struct timeval *)ptr;
+
+               sz.i = sizeof(timeout);
                if (getsockopt(b->num, SOL_SOCKET, SO_SNDTIMEO,
-                       (void*)&timeout, &sz) < 0)
+                       (void*)&timeout, &sz.i) < 0)
                        { perror("getsockopt"); ret = -1; }
                else
                        {
@@ -687,12 +840,20 @@ static long dgram_ctrl(BIO *b, int cmd, long num, void *ptr)
                        tv->tv_usec = (timeout % 1000) * 1000;
                        ret = sizeof(*tv);
                        }
-               }
 #else
+               sz.i = sizeof(struct timeval);
                if ( getsockopt(b->num, SOL_SOCKET, SO_SNDTIMEO, 
-                       ptr, (void *)&ret) < 0)
+                       ptr, (void *)&sz) < 0)
                        { perror("getsockopt"); ret = -1; }
+               else if (sizeof(sz.s)!=sizeof(sz.i) && sz.i==0)
+                       {
+                       OPENSSL_assert(sz.s<=sizeof(struct timeval));
+                       ret = (int)sz.s;
+                       }
+               else
+                       ret = sz.i;
 #endif
+               }
                break;
 #endif
        case BIO_CTRL_DGRAM_GET_SEND_TIMER_EXP:
@@ -721,6 +882,53 @@ static long dgram_ctrl(BIO *b, int cmd, long num, void *ptr)
                        ret = 0;
                break;
 #endif
+       case BIO_CTRL_DGRAM_SET_DONT_FRAG:
+               sockopt_val = num ? 1 : 0;
+
+               switch (data->peer.sa.sa_family)
+                       {
+                       case AF_INET:
+#if defined(IP_DONTFRAG)
+                               if ((ret = setsockopt(b->num, IPPROTO_IP, IP_DONTFRAG,
+                                       &sockopt_val, sizeof(sockopt_val))) < 0)
+                                       { perror("setsockopt"); ret = -1; }
+#elif defined(OPENSSL_SYS_LINUX) && defined(IP_MTUDISCOVER)
+                               if ((sockopt_val = num ? IP_PMTUDISC_PROBE : IP_PMTUDISC_DONT),
+                                   (ret = setsockopt(b->num, IPPROTO_IP, IP_MTU_DISCOVER,
+                                       &sockopt_val, sizeof(sockopt_val))) < 0)
+                                       { perror("setsockopt"); ret = -1; }
+#elif defined(OPENSSL_SYS_WINDOWS) && defined(IP_DONTFRAGMENT)
+                               if ((ret = setsockopt(b->num, IPPROTO_IP, IP_DONTFRAGMENT,
+                                       (const char *)&sockopt_val, sizeof(sockopt_val))) < 0)
+                                       { perror("setsockopt"); ret = -1; }
+#else
+                               ret = -1;
+#endif
+                               break;
+#if OPENSSL_USE_IPV6 
+                       case AF_INET6:
+#if defined(IPV6_DONTFRAG)
+                               if ((ret = setsockopt(b->num, IPPROTO_IPV6, IPV6_DONTFRAG,
+                                       (const void *)&sockopt_val, sizeof(sockopt_val))) < 0)
+                                       { perror("setsockopt"); ret = -1; }
+#elif defined(OPENSSL_SYS_LINUX) && defined(IPV6_MTUDISCOVER)
+                               if ((sockopt_val = num ? IP_PMTUDISC_PROBE : IP_PMTUDISC_DONT),
+                                   (ret = setsockopt(b->num, IPPROTO_IPV6, IPV6_MTU_DISCOVER,
+                                       &sockopt_val, sizeof(sockopt_val))) < 0)
+                                       { perror("setsockopt"); ret = -1; }
+#else
+                               ret = -1;
+#endif
+                               break;
+#endif
+                       default:
+                               ret = -1;
+                               break;
+                       }
+               break;
+       case BIO_CTRL_DGRAM_GET_MTU_OVERHEAD:
+               ret = dgram_get_mtu_overhead(data);
+               break;
        default:
                ret=0;
                break;
@@ -737,6 +945,921 @@ static int dgram_puts(BIO *bp, const char *str)
        return(ret);
        }
 
+#ifndef OPENSSL_NO_SCTP
+BIO_METHOD *BIO_s_datagram_sctp(void)
+       {
+       return(&methods_dgramp_sctp);
+       }
+
+BIO *BIO_new_dgram_sctp(int fd, int close_flag)
+       {
+       BIO *bio;
+       int ret, optval = 20000;
+       int auth_data = 0, auth_forward = 0;
+       unsigned char *p;
+       struct sctp_authchunk auth;
+       struct sctp_authchunks *authchunks;
+       socklen_t sockopt_len;
+#ifdef SCTP_AUTHENTICATION_EVENT
+#ifdef SCTP_EVENT
+       struct sctp_event event;
+#else
+       struct sctp_event_subscribe event;
+#endif
+#endif
+
+       bio=BIO_new(BIO_s_datagram_sctp());
+       if (bio == NULL) return(NULL);
+       BIO_set_fd(bio,fd,close_flag);
+
+       /* Activate SCTP-AUTH for DATA and FORWARD-TSN chunks */
+       auth.sauth_chunk = OPENSSL_SCTP_DATA_CHUNK_TYPE;
+       ret = setsockopt(fd, IPPROTO_SCTP, SCTP_AUTH_CHUNK, &auth, sizeof(struct sctp_authchunk));
+       OPENSSL_assert(ret >= 0);
+       auth.sauth_chunk = OPENSSL_SCTP_FORWARD_CUM_TSN_CHUNK_TYPE;
+       ret = setsockopt(fd, IPPROTO_SCTP, SCTP_AUTH_CHUNK, &auth, sizeof(struct sctp_authchunk));
+       OPENSSL_assert(ret >= 0);
+
+       /* Test if activation was successful. When using accept(),
+        * SCTP-AUTH has to be activated for the listening socket
+        * already, otherwise the connected socket won't use it. */
+       sockopt_len = (socklen_t)(sizeof(sctp_assoc_t) + 256 * sizeof(uint8_t));
+       authchunks = OPENSSL_malloc(sockopt_len);
+       memset(authchunks, 0, sockopt_len);
+       ret = getsockopt(fd, IPPROTO_SCTP, SCTP_LOCAL_AUTH_CHUNKS, authchunks, &sockopt_len);
+       OPENSSL_assert(ret >= 0);
+
+       for (p = (unsigned char*) authchunks->gauth_chunks;
+            p < (unsigned char*) authchunks + sockopt_len;
+            p += sizeof(uint8_t))
+               {
+               if (*p == OPENSSL_SCTP_DATA_CHUNK_TYPE) auth_data = 1;
+               if (*p == OPENSSL_SCTP_FORWARD_CUM_TSN_CHUNK_TYPE) auth_forward = 1;
+               }
+               
+       OPENSSL_free(authchunks);
+
+       OPENSSL_assert(auth_data);
+       OPENSSL_assert(auth_forward);
+
+#ifdef SCTP_AUTHENTICATION_EVENT
+#ifdef SCTP_EVENT
+       memset(&event, 0, sizeof(struct sctp_event));
+       event.se_assoc_id = 0;
+       event.se_type = SCTP_AUTHENTICATION_EVENT;
+       event.se_on = 1;
+       ret = setsockopt(fd, IPPROTO_SCTP, SCTP_EVENT, &event, sizeof(struct sctp_event));
+       OPENSSL_assert(ret >= 0);
+#else
+       sockopt_len = (socklen_t) sizeof(struct sctp_event_subscribe);
+       ret = getsockopt(fd, IPPROTO_SCTP, SCTP_EVENTS, &event, &sockopt_len);
+       OPENSSL_assert(ret >= 0);
+
+       event.sctp_authentication_event = 1;
+
+       ret = setsockopt(fd, IPPROTO_SCTP, SCTP_EVENTS, &event, sizeof(struct sctp_event_subscribe));
+       OPENSSL_assert(ret >= 0);
+#endif
+#endif
+
+       /* Disable partial delivery by setting the min size
+        * larger than the max record size of 2^14 + 2048 + 13
+        */
+       ret = setsockopt(fd, IPPROTO_SCTP, SCTP_PARTIAL_DELIVERY_POINT, &optval, sizeof(optval));
+       OPENSSL_assert(ret >= 0);
+
+       return(bio);
+       }
+
+int BIO_dgram_is_sctp(BIO *bio)
+       {
+       return (BIO_method_type(bio) == BIO_TYPE_DGRAM_SCTP);
+       }
+
+static int dgram_sctp_new(BIO *bi)
+       {
+       bio_dgram_sctp_data *data = NULL;
+
+       bi->init=0;
+       bi->num=0;
+       data = OPENSSL_malloc(sizeof(bio_dgram_sctp_data));
+       if (data == NULL)
+               return 0;
+       memset(data, 0x00, sizeof(bio_dgram_sctp_data));
+#ifdef SCTP_PR_SCTP_NONE
+       data->prinfo.pr_policy = SCTP_PR_SCTP_NONE;
+#endif
+    bi->ptr = data;
+
+       bi->flags=0;
+       return(1);
+       }
+
+static int dgram_sctp_free(BIO *a)
+       {
+       bio_dgram_sctp_data *data;
+
+       if (a == NULL) return(0);
+       if ( ! dgram_clear(a))
+               return 0;
+
+       data = (bio_dgram_sctp_data *)a->ptr;
+       if(data != NULL) OPENSSL_free(data);
+
+       return(1);
+       }
+
+#ifdef SCTP_AUTHENTICATION_EVENT
+void dgram_sctp_handle_auth_free_key_event(BIO *b, union sctp_notification *snp)
+       {
+       int ret;
+       struct sctp_authkey_event* authkeyevent = &snp->sn_auth_event;
+
+       if (authkeyevent->auth_indication == SCTP_AUTH_FREE_KEY)
+               {
+               struct sctp_authkeyid authkeyid;
+
+               /* delete key */
+               authkeyid.scact_keynumber = authkeyevent->auth_keynumber;
+               ret = setsockopt(b->num, IPPROTO_SCTP, SCTP_AUTH_DELETE_KEY,
+                     &authkeyid, sizeof(struct sctp_authkeyid));
+               }
+       }
+#endif
+
+static int dgram_sctp_read(BIO *b, char *out, int outl)
+       {
+       int ret = 0, n = 0, i, optval;
+       socklen_t optlen;
+       bio_dgram_sctp_data *data = (bio_dgram_sctp_data *)b->ptr;
+       union sctp_notification *snp;
+       struct msghdr msg;
+       struct iovec iov;
+       struct cmsghdr *cmsg;
+       char cmsgbuf[512];
+
+       if (out != NULL)
+               {
+               clear_socket_error();
+
+               do
+                       {
+                       memset(&data->rcvinfo, 0x00, sizeof(struct bio_dgram_sctp_rcvinfo));
+                       iov.iov_base = out;
+                       iov.iov_len = outl;
+                       msg.msg_name = NULL;
+                       msg.msg_namelen = 0;
+                       msg.msg_iov = &iov;
+                       msg.msg_iovlen = 1;
+                       msg.msg_control = cmsgbuf;
+                       msg.msg_controllen = 512;
+                       msg.msg_flags = 0;
+                       n = recvmsg(b->num, &msg, 0);
+
+                       if (n <= 0)
+                               {
+                               if (n < 0)
+                                       ret = n;
+                               break;
+                               }
+
+                       if (msg.msg_controllen > 0)
+                               {
+                               for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg))
+                                       {
+                                       if (cmsg->cmsg_level != IPPROTO_SCTP)
+                                               continue;
+#ifdef SCTP_RCVINFO
+                                       if (cmsg->cmsg_type == SCTP_RCVINFO)
+                                               {
+                                               struct sctp_rcvinfo *rcvinfo;
+
+                                               rcvinfo = (struct sctp_rcvinfo *)CMSG_DATA(cmsg);
+                                               data->rcvinfo.rcv_sid = rcvinfo->rcv_sid;
+                                               data->rcvinfo.rcv_ssn = rcvinfo->rcv_ssn;
+                                               data->rcvinfo.rcv_flags = rcvinfo->rcv_flags;
+                                               data->rcvinfo.rcv_ppid = rcvinfo->rcv_ppid;
+                                               data->rcvinfo.rcv_tsn = rcvinfo->rcv_tsn;
+                                               data->rcvinfo.rcv_cumtsn = rcvinfo->rcv_cumtsn;
+                                               data->rcvinfo.rcv_context = rcvinfo->rcv_context;
+                                               }
+#endif
+#ifdef SCTP_SNDRCV
+                                       if (cmsg->cmsg_type == SCTP_SNDRCV)
+                                               {
+                                               struct sctp_sndrcvinfo *sndrcvinfo;
+
+                                               sndrcvinfo = (struct sctp_sndrcvinfo *)CMSG_DATA(cmsg);
+                                               data->rcvinfo.rcv_sid = sndrcvinfo->sinfo_stream;
+                                               data->rcvinfo.rcv_ssn = sndrcvinfo->sinfo_ssn;
+                                               data->rcvinfo.rcv_flags = sndrcvinfo->sinfo_flags;
+                                               data->rcvinfo.rcv_ppid = sndrcvinfo->sinfo_ppid;
+                                               data->rcvinfo.rcv_tsn = sndrcvinfo->sinfo_tsn;
+                                               data->rcvinfo.rcv_cumtsn = sndrcvinfo->sinfo_cumtsn;
+                                               data->rcvinfo.rcv_context = sndrcvinfo->sinfo_context;
+                                               }
+#endif
+                                       }
+                               }
+
+                       if (msg.msg_flags & MSG_NOTIFICATION)
+                               {
+                               snp = (union sctp_notification*) out;
+                               if (snp->sn_header.sn_type == SCTP_SENDER_DRY_EVENT)
+                                       {
+#ifdef SCTP_EVENT
+                                       struct sctp_event event;
+#else
+                                       struct sctp_event_subscribe event;
+                                       socklen_t eventsize;
+#endif
+                                       /* If a message has been delayed until the socket
+                                        * is dry, it can be sent now.
+                                        */
+                                       if (data->saved_message.length > 0)
+                                               {
+                                               dgram_sctp_write(data->saved_message.bio, data->saved_message.data,
+                                                                data->saved_message.length);
+                                               OPENSSL_free(data->saved_message.data);
+                                               data->saved_message.length = 0;
+                                               }
+
+                                       /* disable sender dry event */
+#ifdef SCTP_EVENT
+                                       memset(&event, 0, sizeof(struct sctp_event));
+                                       event.se_assoc_id = 0;
+                                       event.se_type = SCTP_SENDER_DRY_EVENT;
+                                       event.se_on = 0;
+                                       i = setsockopt(b->num, IPPROTO_SCTP, SCTP_EVENT, &event, sizeof(struct sctp_event));
+                                       OPENSSL_assert(i >= 0);
+#else
+                                       eventsize = sizeof(struct sctp_event_subscribe);
+                                       i = getsockopt(b->num, IPPROTO_SCTP, SCTP_EVENTS, &event, &eventsize);
+                                       OPENSSL_assert(i >= 0);
+
+                                       event.sctp_sender_dry_event = 0;
+
+                                       i = setsockopt(b->num, IPPROTO_SCTP, SCTP_EVENTS, &event, sizeof(struct sctp_event_subscribe));
+                                       OPENSSL_assert(i >= 0);
+#endif
+                                       }
+
+#ifdef SCTP_AUTHENTICATION_EVENT
+                               if (snp->sn_header.sn_type == SCTP_AUTHENTICATION_EVENT)
+                                       dgram_sctp_handle_auth_free_key_event(b, snp);
+#endif
+
+                               if (data->handle_notifications != NULL)
+                                       data->handle_notifications(b, data->notification_context, (void*) out);
+
+                               memset(out, 0, outl);
+                               }
+                       else
+                               ret += n;
+                       }
+               while ((msg.msg_flags & MSG_NOTIFICATION) && (msg.msg_flags & MSG_EOR) && (ret < outl));
+
+               if (ret > 0 && !(msg.msg_flags & MSG_EOR))
+                       {
+                       /* Partial message read, this should never happen! */
+
+                       /* The buffer was too small, this means the peer sent
+                        * a message that was larger than allowed. */
+                       if (ret == outl)
+                               return -1;
+
+                       /* Test if socket buffer can handle max record
+                        * size (2^14 + 2048 + 13)
+                        */
+                       optlen = (socklen_t) sizeof(int);
+                       ret = getsockopt(b->num, SOL_SOCKET, SO_RCVBUF, &optval, &optlen);
+                       OPENSSL_assert(ret >= 0);
+                       OPENSSL_assert(optval >= 18445);
+
+                       /* Test if SCTP doesn't partially deliver below
+                        * max record size (2^14 + 2048 + 13)
+                        */
+                       optlen = (socklen_t) sizeof(int);
+                       ret = getsockopt(b->num, IPPROTO_SCTP, SCTP_PARTIAL_DELIVERY_POINT,
+                                        &optval, &optlen);
+                       OPENSSL_assert(ret >= 0);
+                       OPENSSL_assert(optval >= 18445);
+
+                       /* Partially delivered notification??? Probably a bug.... */
+                       OPENSSL_assert(!(msg.msg_flags & MSG_NOTIFICATION));
+
+                       /* Everything seems ok till now, so it's most likely
+                        * a message dropped by PR-SCTP.
+                        */
+                       memset(out, 0, outl);
+                       BIO_set_retry_read(b);
+                       return -1;
+                       }
+
+               BIO_clear_retry_flags(b);
+               if (ret < 0)
+                       {
+                       if (BIO_dgram_should_retry(ret))
+                               {
+                               BIO_set_retry_read(b);
+                               data->_errno = get_last_socket_error();
+                               }
+                       }
+
+               /* Test if peer uses SCTP-AUTH before continuing */
+               if (!data->peer_auth_tested)
+                       {
+                       int ii, auth_data = 0, auth_forward = 0;
+                       unsigned char *p;
+                       struct sctp_authchunks *authchunks;
+
+                       optlen = (socklen_t)(sizeof(sctp_assoc_t) + 256 * sizeof(uint8_t));
+                       authchunks = OPENSSL_malloc(optlen);
+                       memset(authchunks, 0, optlen);
+                       ii = getsockopt(b->num, IPPROTO_SCTP, SCTP_PEER_AUTH_CHUNKS, authchunks, &optlen);
+                       OPENSSL_assert(ii >= 0);
+
+                       for (p = (unsigned char*) authchunks->gauth_chunks;
+                                p < (unsigned char*) authchunks + optlen;
+                                p += sizeof(uint8_t))
+                               {
+                               if (*p == OPENSSL_SCTP_DATA_CHUNK_TYPE) auth_data = 1;
+                               if (*p == OPENSSL_SCTP_FORWARD_CUM_TSN_CHUNK_TYPE) auth_forward = 1;
+                               }
+
+                       OPENSSL_free(authchunks);
+
+                       if (!auth_data || !auth_forward)
+                               {
+                               BIOerr(BIO_F_DGRAM_SCTP_READ,BIO_R_CONNECT_ERROR);
+                               return -1;
+                               }
+
+                       data->peer_auth_tested = 1;
+                       }
+               }
+       return(ret);
+       }
+
+static int dgram_sctp_write(BIO *b, const char *in, int inl)
+       {
+       int ret;
+       bio_dgram_sctp_data *data = (bio_dgram_sctp_data *)b->ptr;
+       struct bio_dgram_sctp_sndinfo *sinfo = &(data->sndinfo);
+       struct bio_dgram_sctp_prinfo *pinfo = &(data->prinfo);
+       struct bio_dgram_sctp_sndinfo handshake_sinfo;
+       struct iovec iov[1];
+       struct msghdr msg;
+       struct cmsghdr *cmsg;
+#if defined(SCTP_SNDINFO) && defined(SCTP_PRINFO)
+       char cmsgbuf[CMSG_SPACE(sizeof(struct sctp_sndinfo)) + CMSG_SPACE(sizeof(struct sctp_prinfo))];
+       struct sctp_sndinfo *sndinfo;
+       struct sctp_prinfo *prinfo;
+#else
+       char cmsgbuf[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))];
+       struct sctp_sndrcvinfo *sndrcvinfo;
+#endif
+
+       clear_socket_error();
+
+       /* If we're send anything else than application data,
+        * disable all user parameters and flags.
+        */
+       if (in[0] != 23) {
+               memset(&handshake_sinfo, 0x00, sizeof(struct bio_dgram_sctp_sndinfo));
+#ifdef SCTP_SACK_IMMEDIATELY
+               handshake_sinfo.snd_flags = SCTP_SACK_IMMEDIATELY;
+#endif
+               sinfo = &handshake_sinfo;
+       }
+
+       /* If we have to send a shutdown alert message and the
+        * socket is not dry yet, we have to save it and send it
+        * as soon as the socket gets dry.
+        */
+       if (data->save_shutdown && !BIO_dgram_sctp_wait_for_dry(b))
+       {
+               data->saved_message.bio = b;
+               data->saved_message.length = inl;
+               data->saved_message.data = OPENSSL_malloc(inl);
+               memcpy(data->saved_message.data, in, inl);
+               return inl;
+       }
+
+       iov[0].iov_base = (char *)in;
+       iov[0].iov_len = inl;
+       msg.msg_name = NULL;
+       msg.msg_namelen = 0;
+       msg.msg_iov = iov;
+       msg.msg_iovlen = 1;
+       msg.msg_control = (caddr_t)cmsgbuf;
+       msg.msg_controllen = 0;
+       msg.msg_flags = 0;
+#if defined(SCTP_SNDINFO) && defined(SCTP_PRINFO)
+       cmsg = (struct cmsghdr *)cmsgbuf;
+       cmsg->cmsg_level = IPPROTO_SCTP;
+       cmsg->cmsg_type = SCTP_SNDINFO;
+       cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_sndinfo));
+       sndinfo = (struct sctp_sndinfo *)CMSG_DATA(cmsg);
+       memset(sndinfo, 0, sizeof(struct sctp_sndinfo));
+       sndinfo->snd_sid = sinfo->snd_sid;
+       sndinfo->snd_flags = sinfo->snd_flags;
+       sndinfo->snd_ppid = sinfo->snd_ppid;
+       sndinfo->snd_context = sinfo->snd_context;
+       msg.msg_controllen += CMSG_SPACE(sizeof(struct sctp_sndinfo));
+
+       cmsg = (struct cmsghdr *)&cmsgbuf[CMSG_SPACE(sizeof(struct sctp_sndinfo))];
+       cmsg->cmsg_level = IPPROTO_SCTP;
+       cmsg->cmsg_type = SCTP_PRINFO;
+       cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_prinfo));
+       prinfo = (struct sctp_prinfo *)CMSG_DATA(cmsg);
+       memset(prinfo, 0, sizeof(struct sctp_prinfo));
+       prinfo->pr_policy = pinfo->pr_policy;
+       prinfo->pr_value = pinfo->pr_value;
+       msg.msg_controllen += CMSG_SPACE(sizeof(struct sctp_prinfo));
+#else
+       cmsg = (struct cmsghdr *)cmsgbuf;
+       cmsg->cmsg_level = IPPROTO_SCTP;
+       cmsg->cmsg_type = SCTP_SNDRCV;
+       cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_sndrcvinfo));
+       sndrcvinfo = (struct sctp_sndrcvinfo *)CMSG_DATA(cmsg);
+       memset(sndrcvinfo, 0, sizeof(struct sctp_sndrcvinfo));
+       sndrcvinfo->sinfo_stream = sinfo->snd_sid;
+       sndrcvinfo->sinfo_flags = sinfo->snd_flags;
+#ifdef __FreeBSD__
+       sndrcvinfo->sinfo_flags |= pinfo->pr_policy;
+#endif
+       sndrcvinfo->sinfo_ppid = sinfo->snd_ppid;
+       sndrcvinfo->sinfo_context = sinfo->snd_context;
+       sndrcvinfo->sinfo_timetolive = pinfo->pr_value;
+       msg.msg_controllen += CMSG_SPACE(sizeof(struct sctp_sndrcvinfo));
+#endif
+
+       ret = sendmsg(b->num, &msg, 0);
+
+       BIO_clear_retry_flags(b);
+       if (ret <= 0)
+               {
+               if (BIO_dgram_should_retry(ret))
+                       {
+                       BIO_set_retry_write(b);  
+                       data->_errno = get_last_socket_error();
+                       }
+               }
+       return(ret);
+       }
+
+static long dgram_sctp_ctrl(BIO *b, int cmd, long num, void *ptr)
+       {
+       long ret=1;
+       bio_dgram_sctp_data *data = NULL;
+       socklen_t sockopt_len = 0;
+       struct sctp_authkeyid authkeyid;
+       struct sctp_authkey *authkey = NULL;
+
+       data = (bio_dgram_sctp_data *)b->ptr;
+
+       switch (cmd)
+               {
+       case BIO_CTRL_DGRAM_QUERY_MTU:
+               /* Set to maximum (2^14)
+                * and ignore user input to enable transport
+                * protocol fragmentation.
+                * Returns always 2^14.
+                */
+               data->mtu = 16384;
+               ret = data->mtu;
+               break;
+       case BIO_CTRL_DGRAM_SET_MTU:
+               /* Set to maximum (2^14)
+                * and ignore input to enable transport
+                * protocol fragmentation.
+                * Returns always 2^14.
+                */
+               data->mtu = 16384;
+               ret = data->mtu;
+               break;
+       case BIO_CTRL_DGRAM_SET_CONNECTED:
+       case BIO_CTRL_DGRAM_CONNECT:
+               /* Returns always -1. */
+               ret = -1;
+               break;
+       case BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT:
+               /* SCTP doesn't need the DTLS timer
+                * Returns always 1.
+                */
+               break;
+       case BIO_CTRL_DGRAM_GET_MTU_OVERHEAD:
+               /* We allow transport protocol fragmentation so this is irrelevant */
+               ret = 0;
+               break;
+       case BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE:
+               if (num > 0)
+                       data->in_handshake = 1;
+               else
+                       data->in_handshake = 0;
+
+               ret = setsockopt(b->num, IPPROTO_SCTP, SCTP_NODELAY, &data->in_handshake, sizeof(int));
+               break;
+       case BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY:
+               /* New shared key for SCTP AUTH.
+                * Returns 0 on success, -1 otherwise.
+                */
+
+               /* Get active key */
+               sockopt_len = sizeof(struct sctp_authkeyid);
+               ret = getsockopt(b->num, IPPROTO_SCTP, SCTP_AUTH_ACTIVE_KEY, &authkeyid, &sockopt_len);
+               if (ret < 0) break;
+
+               /* Add new key */
+               sockopt_len = sizeof(struct sctp_authkey) + 64 * sizeof(uint8_t);
+               authkey = OPENSSL_malloc(sockopt_len);
+               if (authkey == NULL)
+                       {
+                       ret = -1;
+                       break;
+                       }
+               memset(authkey, 0x00, sockopt_len);
+               authkey->sca_keynumber = authkeyid.scact_keynumber + 1;
+#ifndef __FreeBSD__
+               /* This field is missing in FreeBSD 8.2 and earlier,
+                * and FreeBSD 8.3 and higher work without it.
+                */
+               authkey->sca_keylength = 64;
+#endif
+               memcpy(&authkey->sca_key[0], ptr, 64 * sizeof(uint8_t));
+
+               ret = setsockopt(b->num, IPPROTO_SCTP, SCTP_AUTH_KEY, authkey, sockopt_len);
+               OPENSSL_free(authkey);
+               authkey = NULL;
+               if (ret < 0) break;
+
+               /* Reset active key */
+               ret = setsockopt(b->num, IPPROTO_SCTP, SCTP_AUTH_ACTIVE_KEY,
+                     &authkeyid, sizeof(struct sctp_authkeyid));
+               if (ret < 0) break;
+
+               break;
+       case BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY:
+               /* Returns 0 on success, -1 otherwise. */
+
+               /* Get active key */
+               sockopt_len = sizeof(struct sctp_authkeyid);
+               ret = getsockopt(b->num, IPPROTO_SCTP, SCTP_AUTH_ACTIVE_KEY, &authkeyid, &sockopt_len);
+               if (ret < 0) break;
+
+               /* Set active key */
+               authkeyid.scact_keynumber = authkeyid.scact_keynumber + 1;
+               ret = setsockopt(b->num, IPPROTO_SCTP, SCTP_AUTH_ACTIVE_KEY,
+                     &authkeyid, sizeof(struct sctp_authkeyid));
+               if (ret < 0) break;
+
+               /* CCS has been sent, so remember that and fall through
+                * to check if we need to deactivate an old key
+                */
+               data->ccs_sent = 1;
+
+       case BIO_CTRL_DGRAM_SCTP_AUTH_CCS_RCVD:
+               /* Returns 0 on success, -1 otherwise. */
+
+               /* Has this command really been called or is this just a fall-through? */
+               if (cmd == BIO_CTRL_DGRAM_SCTP_AUTH_CCS_RCVD)
+                       data->ccs_rcvd = 1;
+
+               /* CSS has been both, received and sent, so deactivate an old key */
+               if (data->ccs_rcvd == 1 && data->ccs_sent == 1)
+                       {
+                       /* Get active key */
+                       sockopt_len = sizeof(struct sctp_authkeyid);
+                       ret = getsockopt(b->num, IPPROTO_SCTP, SCTP_AUTH_ACTIVE_KEY, &authkeyid, &sockopt_len);
+                       if (ret < 0) break;
+
+                       /* Deactivate key or delete second last key if
+                        * SCTP_AUTHENTICATION_EVENT is not available.
+                        */
+                       authkeyid.scact_keynumber = authkeyid.scact_keynumber - 1;
+#ifdef SCTP_AUTH_DEACTIVATE_KEY
+                       sockopt_len = sizeof(struct sctp_authkeyid);
+                       ret = setsockopt(b->num, IPPROTO_SCTP, SCTP_AUTH_DEACTIVATE_KEY,
+                             &authkeyid, sockopt_len);
+                       if (ret < 0) break;
+#endif
+#ifndef SCTP_AUTHENTICATION_EVENT
+                       if (authkeyid.scact_keynumber > 0)
+                               {
+                               authkeyid.scact_keynumber = authkeyid.scact_keynumber - 1;
+                               ret = setsockopt(b->num, IPPROTO_SCTP, SCTP_AUTH_DELETE_KEY,
+                                         &authkeyid, sizeof(struct sctp_authkeyid));
+                               if (ret < 0) break;
+                               }
+#endif
+
+                       data->ccs_rcvd = 0;
+                       data->ccs_sent = 0;
+                       }
+               break;
+       case BIO_CTRL_DGRAM_SCTP_GET_SNDINFO:
+               /* Returns the size of the copied struct. */
+               if (num > (long) sizeof(struct bio_dgram_sctp_sndinfo))
+                       num = sizeof(struct bio_dgram_sctp_sndinfo);
+
+               memcpy(ptr, &(data->sndinfo), num);
+               ret = num;
+               break;
+       case BIO_CTRL_DGRAM_SCTP_SET_SNDINFO:
+               /* Returns the size of the copied struct. */
+               if (num > (long) sizeof(struct bio_dgram_sctp_sndinfo))
+                       num = sizeof(struct bio_dgram_sctp_sndinfo);
+
+               memcpy(&(data->sndinfo), ptr, num);
+               break;
+       case BIO_CTRL_DGRAM_SCTP_GET_RCVINFO:
+               /* Returns the size of the copied struct. */
+               if (num > (long) sizeof(struct bio_dgram_sctp_rcvinfo))
+                       num = sizeof(struct bio_dgram_sctp_rcvinfo);
+
+               memcpy(ptr, &data->rcvinfo, num);
+
+               ret = num;
+               break;
+       case BIO_CTRL_DGRAM_SCTP_SET_RCVINFO:
+               /* Returns the size of the copied struct. */
+               if (num > (long) sizeof(struct bio_dgram_sctp_rcvinfo))
+                       num = sizeof(struct bio_dgram_sctp_rcvinfo);
+
+               memcpy(&(data->rcvinfo), ptr, num);
+               break;
+       case BIO_CTRL_DGRAM_SCTP_GET_PRINFO:
+               /* Returns the size of the copied struct. */
+               if (num > (long) sizeof(struct bio_dgram_sctp_prinfo))
+                       num = sizeof(struct bio_dgram_sctp_prinfo);
+
+               memcpy(ptr, &(data->prinfo), num);
+               ret = num;
+               break;
+       case BIO_CTRL_DGRAM_SCTP_SET_PRINFO:
+               /* Returns the size of the copied struct. */
+               if (num > (long) sizeof(struct bio_dgram_sctp_prinfo))
+                       num = sizeof(struct bio_dgram_sctp_prinfo);
+
+               memcpy(&(data->prinfo), ptr, num);
+               break;
+       case BIO_CTRL_DGRAM_SCTP_SAVE_SHUTDOWN:
+               /* Returns always 1. */
+               if (num > 0)
+                       data->save_shutdown = 1;
+               else
+                       data->save_shutdown = 0;
+               break;
+
+       default:
+               /* Pass to default ctrl function to
+                * process SCTP unspecific commands
+                */
+               ret=dgram_ctrl(b, cmd, num, ptr);
+               break;
+               }
+       return(ret);
+       }
+
+int BIO_dgram_sctp_notification_cb(BIO *b,
+                                   void (*handle_notifications)(BIO *bio, void *context, void *buf),
+                                   void *context)
+       {
+       bio_dgram_sctp_data *data = (bio_dgram_sctp_data *) b->ptr;
+
+       if (handle_notifications != NULL)
+               {
+               data->handle_notifications = handle_notifications;
+               data->notification_context = context;
+               }
+       else
+               return -1;
+
+       return 0;
+       }
+
+int BIO_dgram_sctp_wait_for_dry(BIO *b)
+{
+       int is_dry = 0;
+       int n, sockflags, ret;
+       union sctp_notification snp;
+       struct msghdr msg;
+       struct iovec iov;
+#ifdef SCTP_EVENT
+       struct sctp_event event;
+#else
+       struct sctp_event_subscribe event;
+       socklen_t eventsize;
+#endif
+       bio_dgram_sctp_data *data = (bio_dgram_sctp_data *)b->ptr;
+
+       /* set sender dry event */
+#ifdef SCTP_EVENT
+       memset(&event, 0, sizeof(struct sctp_event));
+       event.se_assoc_id = 0;
+       event.se_type = SCTP_SENDER_DRY_EVENT;
+       event.se_on = 1;
+       ret = setsockopt(b->num, IPPROTO_SCTP, SCTP_EVENT, &event, sizeof(struct sctp_event));
+#else
+       eventsize = sizeof(struct sctp_event_subscribe);
+       ret = getsockopt(b->num, IPPROTO_SCTP, SCTP_EVENTS, &event, &eventsize);
+       if (ret < 0)
+               return -1;
+       
+       event.sctp_sender_dry_event = 1;
+       
+       ret = setsockopt(b->num, IPPROTO_SCTP, SCTP_EVENTS, &event, sizeof(struct sctp_event_subscribe));
+#endif
+       if (ret < 0)
+               return -1;
+
+       /* peek for notification */
+       memset(&snp, 0x00, sizeof(union sctp_notification));
+       iov.iov_base = (char *)&snp;
+       iov.iov_len = sizeof(union sctp_notification);
+       msg.msg_name = NULL;
+       msg.msg_namelen = 0;
+       msg.msg_iov = &iov;
+       msg.msg_iovlen = 1;
+       msg.msg_control = NULL;
+       msg.msg_controllen = 0;
+       msg.msg_flags = 0;
+
+       n = recvmsg(b->num, &msg, MSG_PEEK);
+       if (n <= 0)
+               {
+               if ((n < 0) && (get_last_socket_error() != EAGAIN) && (get_last_socket_error() != EWOULDBLOCK))
+                       return -1;
+               else
+                       return 0;
+               }
+
+       /* if we find a notification, process it and try again if necessary */
+       while (msg.msg_flags & MSG_NOTIFICATION)
+               {
+               memset(&snp, 0x00, sizeof(union sctp_notification));
+               iov.iov_base = (char *)&snp;
+               iov.iov_len = sizeof(union sctp_notification);
+               msg.msg_name = NULL;
+               msg.msg_namelen = 0;
+               msg.msg_iov = &iov;
+               msg.msg_iovlen = 1;
+               msg.msg_control = NULL;
+               msg.msg_controllen = 0;
+               msg.msg_flags = 0;
+
+               n = recvmsg(b->num, &msg, 0);
+               if (n <= 0)
+                       {
+                       if ((n < 0) && (get_last_socket_error() != EAGAIN) && (get_last_socket_error() != EWOULDBLOCK))
+                               return -1;
+                       else
+                               return is_dry;
+                       }
+               
+               if (snp.sn_header.sn_type == SCTP_SENDER_DRY_EVENT)
+                       {
+                       is_dry = 1;
+
+                       /* disable sender dry event */
+#ifdef SCTP_EVENT
+                       memset(&event, 0, sizeof(struct sctp_event));
+                       event.se_assoc_id = 0;
+                       event.se_type = SCTP_SENDER_DRY_EVENT;
+                       event.se_on = 0;
+                       ret = setsockopt(b->num, IPPROTO_SCTP, SCTP_EVENT, &event, sizeof(struct sctp_event));
+#else
+                       eventsize = (socklen_t) sizeof(struct sctp_event_subscribe);
+                       ret = getsockopt(b->num, IPPROTO_SCTP, SCTP_EVENTS, &event, &eventsize);
+                       if (ret < 0)
+                               return -1;
+
+                       event.sctp_sender_dry_event = 0;
+
+                       ret = setsockopt(b->num, IPPROTO_SCTP, SCTP_EVENTS, &event, sizeof(struct sctp_event_subscribe));
+#endif
+                       if (ret < 0)
+                               return -1;
+                       }
+
+#ifdef SCTP_AUTHENTICATION_EVENT
+               if (snp.sn_header.sn_type == SCTP_AUTHENTICATION_EVENT)
+                       dgram_sctp_handle_auth_free_key_event(b, &snp);
+#endif
+
+               if (data->handle_notifications != NULL)
+                       data->handle_notifications(b, data->notification_context, (void*) &snp);
+
+               /* found notification, peek again */
+               memset(&snp, 0x00, sizeof(union sctp_notification));
+               iov.iov_base = (char *)&snp;
+               iov.iov_len = sizeof(union sctp_notification);
+               msg.msg_name = NULL;
+               msg.msg_namelen = 0;
+               msg.msg_iov = &iov;
+               msg.msg_iovlen = 1;
+               msg.msg_control = NULL;
+               msg.msg_controllen = 0;
+               msg.msg_flags = 0;
+
+               /* if we have seen the dry already, don't wait */
+               if (is_dry)
+                       {
+                       sockflags = fcntl(b->num, F_GETFL, 0);
+                       fcntl(b->num, F_SETFL, O_NONBLOCK);
+                       }
+
+               n = recvmsg(b->num, &msg, MSG_PEEK);
+
+               if (is_dry)
+                       {
+                       fcntl(b->num, F_SETFL, sockflags);
+                       }
+
+               if (n <= 0)
+                       {
+                       if ((n < 0) && (get_last_socket_error() != EAGAIN) && (get_last_socket_error() != EWOULDBLOCK))
+                               return -1;
+                       else
+                               return is_dry;
+                       }
+               }
+
+       /* read anything else */
+       return is_dry;
+}
+
+int BIO_dgram_sctp_msg_waiting(BIO *b)
+       {
+       int n, sockflags;
+       union sctp_notification snp;
+       struct msghdr msg;
+       struct iovec iov;
+       bio_dgram_sctp_data *data = (bio_dgram_sctp_data *)b->ptr;
+
+       /* Check if there are any messages waiting to be read */
+       do
+               {
+               memset(&snp, 0x00, sizeof(union sctp_notification));
+               iov.iov_base = (char *)&snp;
+               iov.iov_len = sizeof(union sctp_notification);
+               msg.msg_name = NULL;
+               msg.msg_namelen = 0;
+               msg.msg_iov = &iov;
+               msg.msg_iovlen = 1;
+               msg.msg_control = NULL;
+               msg.msg_controllen = 0;
+               msg.msg_flags = 0;
+
+               sockflags = fcntl(b->num, F_GETFL, 0);
+               fcntl(b->num, F_SETFL, O_NONBLOCK);
+               n = recvmsg(b->num, &msg, MSG_PEEK);
+               fcntl(b->num, F_SETFL, sockflags);
+
+               /* if notification, process and try again */
+               if (n > 0 && (msg.msg_flags & MSG_NOTIFICATION))
+                       {
+#ifdef SCTP_AUTHENTICATION_EVENT
+                       if (snp.sn_header.sn_type == SCTP_AUTHENTICATION_EVENT)
+                               dgram_sctp_handle_auth_free_key_event(b, &snp);
+#endif
+
+                       memset(&snp, 0x00, sizeof(union sctp_notification));
+                       iov.iov_base = (char *)&snp;
+                       iov.iov_len = sizeof(union sctp_notification);
+                       msg.msg_name = NULL;
+                       msg.msg_namelen = 0;
+                       msg.msg_iov = &iov;
+                       msg.msg_iovlen = 1;
+                       msg.msg_control = NULL;
+                       msg.msg_controllen = 0;
+                       msg.msg_flags = 0;
+                       n = recvmsg(b->num, &msg, 0);
+
+                       if (data->handle_notifications != NULL)
+                               data->handle_notifications(b, data->notification_context, (void*) &snp);
+                       }
+
+               } while (n > 0 && (msg.msg_flags & MSG_NOTIFICATION));
+
+       /* Return 1 if there is a message to be read, return 0 otherwise. */
+       if (n > 0)
+               return 1;
+       else
+               return 0;
+       }
+
+static int dgram_sctp_puts(BIO *bp, const char *str)
+       {
+       int n,ret;
+
+       n=strlen(str);
+       ret=dgram_sctp_write(bp,str,n);
+       return(ret);
+       }
+#endif
+
 static int BIO_dgram_should_retry(int i)
        {
        int err;
@@ -745,9 +1868,13 @@ static int BIO_dgram_should_retry(int i)
                {
                err=get_last_socket_error();
 
-#if defined(OPENSSL_SYS_WINDOWS) && 0 /* more microsoft stupidity? perhaps not? Ben 4/1/99 */
-               if ((i == -1) && (err == 0))
-                       return(1);
+#if defined(OPENSSL_SYS_WINDOWS)
+       /* If the socket return value (i) is -1
+        * and err is unexpectedly 0 at this point,
+        * the error code was overwritten by
+        * another system call before this error
+        * handling is called.
+        */
 #endif
 
                return(BIO_dgram_non_fatal_error(err));
@@ -810,15 +1937,22 @@ int BIO_dgram_non_fatal_error(int err)
                }
        return(0);
        }
-#endif
 
 static void get_current_time(struct timeval *t)
        {
-#ifdef OPENSSL_SYS_WIN32
-       struct _timeb tb;
-       _ftime(&tb);
-       t->tv_sec = (long)tb.time;
-       t->tv_usec = (long)tb.millitm * 1000;
+#if defined(_WIN32)
+       SYSTEMTIME st;
+       union { unsigned __int64 ul; FILETIME ft; } now;
+
+       GetSystemTime(&st);
+       SystemTimeToFileTime(&st,&now.ft);
+#ifdef __MINGW32__
+       now.ul -= 116444736000000000ULL;
+#else
+       now.ul -= 116444736000000000UI64;       /* re-bias to 1/1/1970 */
+#endif
+       t->tv_sec  = (long)(now.ul/10000000);
+       t->tv_usec = ((int)(now.ul%10000000))/10;
 #elif defined(OPENSSL_SYS_VMS)
        struct timeb tb;
        ftime(&tb);
@@ -828,3 +1962,5 @@ static void get_current_time(struct timeval *t)
        gettimeofday(t, NULL);
 #endif
        }
+
+#endif