Finally fix bug #50088 (socket/netconn: data before RST should be readable) and added a unit test for it

test/unit/api/test_sockets.c

@@ -8,6 +8,7 @@
 
 #include "lwip/tcpip.h"
 #include "lwip/priv/tcp_priv.h"
+#include "lwip/api.h"
 
 
 static int
@@ -641,6 +642,149 @@ START_TEST(test_sockets_select)
 }
 END_TEST
 
+START_TEST(test_sockets_recv_after_rst)
+{
+  int sl, sact;
+  int spass = -1;
+  int ret;
+  struct sockaddr_in sa_listen;
+  const u16_t port = 1234;
+  int arg;
+  const char txbuf[] = "something";
+  char rxbuf[16];
+  struct lwip_sock *sact_sock;
+  int err;
+  LWIP_UNUSED_ARG(_i);
+
+  fail_unless(test_sockets_get_used_count() == 0);
+
+  memset(&sa_listen, 0, sizeof(sa_listen));
+  sa_listen.sin_family = AF_INET;
+  sa_listen.sin_port = PP_HTONS(port);
+  sa_listen.sin_addr.s_addr = PP_HTONL(INADDR_LOOPBACK);
+
+  /* set up the listener */
+  sl = lwip_socket(AF_INET, SOCK_STREAM, 0);
+  fail_unless(sl >= 0);
+  fail_unless(test_sockets_get_used_count() == 0);
+
+  ret = lwip_bind(sl, (struct sockaddr *)&sa_listen, sizeof(sa_listen));
+  fail_unless(ret == 0);
+  ret = lwip_listen(sl, 0);
+  fail_unless(ret == 0);
+
+  /* set up the client */
+  sact = lwip_socket(AF_INET, SOCK_STREAM, 0);
+  fail_unless(sact >= 0);
+  fail_unless(test_sockets_get_used_count() == 0);
+  /* set the client to nonblocking to simplify this test */
+  arg = 1;
+  ret = lwip_ioctl(sact, FIONBIO, &arg);
+  fail_unless(ret == 0);
+  /* connect */
+  do {
+    ret = lwip_connect(sact, (struct sockaddr *)&sa_listen, sizeof(sa_listen));
+    err = errno;
+    fail_unless((ret == 0) || (ret == -1));
+    if (ret != 0) {
+      if (err == EISCONN) {
+        /* Although this is not valid, use EISCONN as an indicator for successful connection.
+           This marks us as "connect phase is done". On error, we would either have a different
+           errno code or "send" fails later... -> good enough for this test. */
+        ret = 0;
+      } else {
+        fail_unless(err == EINPROGRESS);
+        if (err != EINPROGRESS) {
+          goto cleanup;
+        }
+        /* we're in progress: little side check: test for EALREADY */
+        ret = lwip_connect(sact, (struct sockaddr *)&sa_listen, sizeof(sa_listen));
+        err = errno;
+        fail_unless(ret == -1);
+        fail_unless(err == EALREADY);
+        if ((ret != -1) || (err != EALREADY)) {
+          goto cleanup;
+        }
+      }
+      tcpip_thread_poll_one();
+      tcpip_thread_poll_one();
+      tcpip_thread_poll_one();
+      tcpip_thread_poll_one();
+    }
+  } while (ret != 0);
+  fail_unless(ret == 0);
+
+  /* accept the server connection part */
+  spass = lwip_accept(sl, NULL, NULL);
+  fail_unless(spass >= 0);
+
+  /* write data from client */
+  ret = lwip_send(sact, txbuf, sizeof(txbuf), 0);
+  fail_unless(ret == sizeof(txbuf));
+
+  tcpip_thread_poll_one();
+  tcpip_thread_poll_one();
+
+  /* issue RST (This is a HACK, don't try this in your own app!) */
+  sact_sock = lwip_socket_dbg_get_socket(sact);
+  fail_unless(sact_sock != NULL);
+  if (sact_sock != NULL) {
+    struct netconn *sact_conn = sact_sock->conn;
+    fail_unless(sact_conn != NULL);
+    if (sact_conn != NULL) {
+      struct tcp_pcb *pcb = sact_conn->pcb.tcp;
+      fail_unless(pcb != NULL);
+      if (pcb != NULL) {
+        tcp_rst(pcb, pcb->snd_nxt, pcb->rcv_nxt, &pcb->local_ip, &pcb->remote_ip,
+                     pcb->local_port, pcb->remote_port);
+      }
+    }
+  }
+  tcpip_thread_poll_one();
+  tcpip_thread_poll_one();
+
+  /* expect to receive data first */
+  ret = lwip_recv(spass, rxbuf, sizeof(rxbuf), 0);
+  fail_unless(ret > 0);
+  tcpip_thread_poll_one();
+  tcpip_thread_poll_one();
+
+  /* expect to receive RST indication */
+  ret = lwip_recv(spass, rxbuf, sizeof(rxbuf), 0);
+  fail_unless(ret == -1);
+  err = errno;
+  fail_unless(err == ECONNRESET);
+  tcpip_thread_poll_one();
+  tcpip_thread_poll_one();
+
+  /* expect to receive ENOTCONN indication */
+  ret = lwip_recv(spass, rxbuf, sizeof(rxbuf), 0);
+  fail_unless(ret == -1);
+  err = errno;
+  fail_unless(err == ENOTCONN);
+  tcpip_thread_poll_one();
+  tcpip_thread_poll_one();
+
+  /* expect to receive ENOTCONN indication */
+  ret = lwip_recv(spass, rxbuf, sizeof(rxbuf), 0);
+  fail_unless(ret == -1);
+  err = errno;
+  fail_unless(err == ENOTCONN);
+  tcpip_thread_poll_one();
+  tcpip_thread_poll_one();
+
+cleanup:
+  ret = lwip_close(sl);
+  fail_unless(ret == 0);
+  ret = lwip_close(sact);
+  fail_unless(ret == 0);
+  if (spass >= 0) {
+    ret = lwip_close(spass);
+    fail_unless(ret == 0);
+  }
+}
+END_TEST
+
 /** Create the suite including all tests for this module */
 Suite *
 sockets_suite(void)
@@ -650,6 +794,7 @@ sockets_suite(void)
     TESTFUNC(test_sockets_allfunctions_basic),
     TESTFUNC(test_sockets_msgapis),
     TESTFUNC(test_sockets_select),
+    TESTFUNC(test_sockets_recv_after_rst),
   };
   return create_suite("SOCKETS", tests, sizeof(tests)/sizeof(testfunc), sockets_setup, sockets_teardown);
 }