X-Git-Url: http://git.meshlink.io/?a=blobdiff_plain;f=src%2Futcp.c;h=c21e7067b89610c17182eae3dce57b58a9dfa274;hb=57d7814d3c211a46f6a6fe7dd995307cb9a6f41e;hp=ec74923dd128a85c4b730fefa015127e40a40c8a;hpb=21e47177687ac553303005941b971092e973575a;p=meshlink diff --git a/src/utcp.c b/src/utcp.c index ec74923d..c21e7067 100644 --- a/src/utcp.c +++ b/src/utcp.c @@ -17,16 +17,7 @@ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ -#define _GNU_SOURCE - -#include -#include -#include -#include -#include -#include -#include -#include +#include "system.h" #include #include "utcp_priv.h" @@ -205,6 +196,16 @@ static bool buffer_wraps(struct buffer *buf) { } static bool buffer_resize(struct buffer *buf, uint32_t newsize) { + assert(!buf->external); + + if(!newsize) { + free(buf->data); + buf->data = NULL; + buf->size = 0; + buf->offset = 0; + return true; + } + char *newdata = realloc(buf->data, newsize); if(!newdata) { @@ -404,8 +405,94 @@ static bool buffer_set_size(struct buffer *buf, uint32_t minsize, uint32_t maxsi return buf->size >= minsize || buffer_resize(buf, minsize); } +static void buffer_transfer(struct buffer *buf, char *newdata, size_t newsize) { + if(buffer_wraps(buf)) { + // Old situation: + // [345......012] + // New situation: + // [012345......] + uint32_t tailsize = buf->size - buf->offset; + memcpy(newdata, buf->data + buf->offset, tailsize); + memcpy(newdata + tailsize, buf->data, buf->used - tailsize); + } else { + // Old situation: + // [....012345..] + // New situation: + // [012345......] + memcpy(newdata, buf->data + buf->offset, buf->used); + } + + buf->offset = 0; + buf->size = newsize; +} + +static void set_buffer_storage(struct buffer *buf, char *data, size_t size) { + if(size > UINT32_MAX) { + size = UINT32_MAX; + } + + buf->maxsize = size; + + if(data) { + if(buf->external) { + // Don't allow resizing an external buffer + abort(); + } + + if(size < buf->used) { + // Ignore requests for an external buffer if we are already using more than it can store + return; + } + + // Transition from internal to external buffer + buffer_transfer(buf, data, size); + free(buf->data); + buf->data = data; + buf->external = true; + } else if(buf->external) { + // Transition from external to internal buf + size_t minsize = buf->used <= DEFAULT_SNDBUFSIZE ? DEFAULT_SNDBUFSIZE : buf->used; + + if(minsize) { + data = malloc(minsize); + + if(!data) { + // Cannot handle this + abort(); + } + + buffer_transfer(buf, data, minsize); + buf->data = data; + } else { + buf->data = NULL; + buf->size = 0; + } + + buf->external = false; + } else { + // Realloc internal storage + size_t minsize = buf->used <= DEFAULT_SNDBUFSIZE ? DEFAULT_SNDBUFSIZE : buf->used; + + if(minsize) { + data = realloc(buf->data, minsize); + + if(data) { + buf->data = data; + buf->size = minsize; + } + } else { + free(buf->data); + buf->data = NULL; + buf->size = 0; + } + } +} + static void buffer_exit(struct buffer *buf) { - free(buf->data); + if(!buf->external) { + free(buf->data); + } + memset(buf, 0, sizeof(*buf)); } @@ -659,6 +746,7 @@ void utcp_accept(struct utcp_connection *c, utcp_recv_t recv, void *priv) { debug(c, "accepted %p %p\n", c, recv, priv); c->recv = recv; c->priv = priv; + c->do_poll = true; set_state(c, ESTABLISHED); } @@ -1301,7 +1389,7 @@ ssize_t utcp_recv(struct utcp *utcp, const void *data, size_t len) { if(hdr.ctl & SYN && !(hdr.ctl & ACK) && utcp->accept) { // If we don't want to accept it, send a RST back - if((utcp->pre_accept && !utcp->pre_accept(utcp, hdr.dst))) { + if((utcp->listen && !utcp->listen(utcp, hdr.dst))) { len = 1; goto reset; } @@ -1376,7 +1464,7 @@ synack: if(c->state == CLOSED) { debug(c, "got packet for closed connection\n"); - return 0; + goto reset; } // It is for an existing connection. @@ -1464,17 +1552,6 @@ synack: } } - if(hdr.ctl & ACK && (seqdiff(hdr.ack, c->snd.last) > 0 || seqdiff(hdr.ack, c->snd.una) < 0)) { - debug(c, "packet ack seqno out of range, %u <= %u < %u\n", c->snd.una, hdr.ack, c->snd.una + c->sndbuf.used); - - // Ignore unacceptable RST packets. - if(hdr.ctl & RST) { - return 0; - } - - goto reset; - } - // 2. Handle RST packets if(hdr.ctl & RST) { @@ -1564,6 +1641,11 @@ synack: // 3. Advance snd.una + if(seqdiff(hdr.ack, c->snd.last) > 0 || seqdiff(hdr.ack, c->snd.una) < 0) { + debug(c, "packet ack seqno out of range, %u <= %u < %u\n", c->snd.una, hdr.ack, c->snd.una + c->sndbuf.used); + goto reset; + } + advanced = seqdiff(hdr.ack, c->snd.una); if(advanced) { @@ -1727,6 +1809,7 @@ skip_ack: c->snd.last++; set_state(c, FIN_WAIT_1); } else { + c->do_poll = true; set_state(c, ESTABLISHED); } @@ -1785,8 +1868,15 @@ skip_ack: return 0; case ESTABLISHED: + break; + case FIN_WAIT_1: case FIN_WAIT_2: + if(c->reapable) { + // We already closed the connection and are not interested in more data. + goto reset; + } + break; case CLOSE_WAIT: @@ -2008,7 +2098,7 @@ static bool reset_connection(struct utcp_connection *c) { hdr.src = c->src; hdr.dst = c->dst; hdr.seq = c->snd.nxt; - hdr.ack = 0; + hdr.ack = c->rcv.nxt; hdr.wnd = 0; hdr.ctl = RST; @@ -2017,6 +2107,15 @@ static bool reset_connection(struct utcp_connection *c) { return true; } +static void set_reapable(struct utcp_connection *c) { + set_buffer_storage(&c->sndbuf, NULL, DEFAULT_MTU); + set_buffer_storage(&c->rcvbuf, NULL, DEFAULT_MTU); + + c->recv = NULL; + c->poll = NULL; + c->reapable = true; +} + // Closes all the opened connections void utcp_abort_all_connections(struct utcp *utcp) { if(!utcp) { @@ -2034,7 +2133,7 @@ void utcp_abort_all_connections(struct utcp *utcp) { utcp_recv_t old_recv = c->recv; utcp_poll_t old_poll = c->poll; - reset_connection(c); + utcp_abort(c); if(old_recv) { errno = 0; @@ -2051,18 +2150,11 @@ void utcp_abort_all_connections(struct utcp *utcp) { } int utcp_close(struct utcp_connection *c) { - if(c->rcvbuf.used) { - fprintf(stderr, "UTCP channel closed with stuff in receive buffer\n"); - return reset_connection(c) ? 0 : -1; - } - if(utcp_shutdown(c, SHUT_RDWR) && errno != ENOTCONN) { return -1; } - c->recv = NULL; - c->poll = NULL; - c->reapable = true; + set_reapable(c); return 0; } @@ -2071,7 +2163,7 @@ int utcp_abort(struct utcp_connection *c) { return -1; } - c->reapable = true; + set_reapable(c); return 0; } @@ -2166,7 +2258,7 @@ bool utcp_is_active(struct utcp *utcp) { return false; } -struct utcp *utcp_init(utcp_accept_t accept, utcp_pre_accept_t pre_accept, utcp_send_t send, void *priv) { +struct utcp *utcp_init(utcp_accept_t accept, utcp_listen_t listen, utcp_send_t send, void *priv) { if(!send) { errno = EFAULT; return NULL; @@ -2192,7 +2284,7 @@ struct utcp *utcp_init(utcp_accept_t accept, utcp_pre_accept_t pre_accept, utcp_ } utcp->accept = accept; - utcp->pre_accept = pre_accept; + utcp->listen = listen; utcp->send = send; utcp->priv = priv; utcp->timeout = DEFAULT_USER_TIMEOUT; // sec @@ -2326,16 +2418,12 @@ size_t utcp_get_sndbuf_free(struct utcp_connection *c) { } } -void utcp_set_sndbuf(struct utcp_connection *c, size_t size) { +void utcp_set_sndbuf(struct utcp_connection *c, void *data, size_t size) { if(!c) { return; } - c->sndbuf.maxsize = size; - - if(c->sndbuf.maxsize != size) { - c->sndbuf.maxsize = -1; - } + set_buffer_storage(&c->sndbuf, data, size); c->do_poll = is_reliable(c) && buffer_free(&c->sndbuf); } @@ -2352,16 +2440,12 @@ size_t utcp_get_rcvbuf_free(struct utcp_connection *c) { } } -void utcp_set_rcvbuf(struct utcp_connection *c, size_t size) { +void utcp_set_rcvbuf(struct utcp_connection *c, void *data, size_t size) { if(!c) { return; } - c->rcvbuf.maxsize = size; - - if(c->rcvbuf.maxsize != size) { - c->rcvbuf.maxsize = -1; - } + set_buffer_storage(&c->rcvbuf, data, size); } size_t utcp_get_sendq(struct utcp_connection *c) { @@ -2409,10 +2493,10 @@ void utcp_set_poll_cb(struct utcp_connection *c, utcp_poll_t poll) { } } -void utcp_set_accept_cb(struct utcp *utcp, utcp_accept_t accept, utcp_pre_accept_t pre_accept) { +void utcp_set_accept_cb(struct utcp *utcp, utcp_accept_t accept, utcp_listen_t listen) { if(utcp) { utcp->accept = accept; - utcp->pre_accept = pre_accept; + utcp->listen = listen; } } @@ -2439,6 +2523,11 @@ void utcp_expect_data(struct utcp_connection *c, bool expect) { } } +void utcp_set_flags(struct utcp_connection *c, uint32_t flags) { + c->flags &= ~UTCP_CHANGEABLE_FLAGS; + c->flags |= flags & UTCP_CHANGEABLE_FLAGS; +} + void utcp_offline(struct utcp *utcp, bool offline) { struct timespec now; clock_gettime(UTCP_CLOCK, &now);