fixes #1701 compat: nn_reallocmsg is incorrect

3 files changed, 113 insertions, 21 deletions

diff --git a/src/compat/nanomsg/CMakeLists.txt b/src/compat/nanomsg/CMakeLists.txt
index 953eabad..51679b34 100644
--- a/src/compat/nanomsg/CMakeLists.txt
+++ b/src/compat/nanomsg/CMakeLists.txt
@@ -1,5 +1,5 @@
 #
-# Copyright 2020 Staysail Systems, Inc. <info@staysail.tech>
+# Copyright 2023 Staysail Systems, Inc. <info@staysail.tech>
 #
 # This software is supplied under the terms of the MIT License, a
 # copy of which should be located in the distribution where this
@@ -11,4 +11,5 @@ nng_sources(nn.c)
 
 set(NNG_TEST_PREFIX ${NNG_TEST_PREFIX}.compat.nanomsg)
 
-nng_test(compat_tcp_test)
\ No newline at end of file
+nng_test(compat_msg_test)
+nng_test(compat_tcp_test)
diff --git a/src/compat/nanomsg/compat_msg_test.c b/src/compat/nanomsg/compat_msg_test.c
new file mode 100644
index 00000000..d037a0b4
--- /dev/null
+++ b/src/compat/nanomsg/compat_msg_test.c
@@ -0,0 +1,92 @@
+//
+// Copyright 2023 Staysail Systems, Inc. <info@staysail.tech>
+//
+// This software is supplied under the terms of the MIT License, a
+// copy of which should be located in the distribution where this
+// file was obtained (LICENSE.txt).  A copy of the license may also be
+// found online at https://opensource.org/licenses/MIT.
+//
+
+#include <nng/compat/nanomsg/nn.h>
+#include <nng/compat/nanomsg/pair.h>
+#include <nng/compat/nanomsg/tcp.h>
+
+#include "nuts_compat.h"
+
+#include <nuts.h>
+
+void
+test_msg_alloc(void)
+{
+	char *msg;
+	msg = nn_allocmsg(1, 0);
+	NUTS_TRUE(msg != NULL);
+	NUTS_NN_PASS(nn_freemsg(msg));
+}
+
+void
+test_msg_zero_length(void)
+{
+	char *msg;
+	msg = nn_allocmsg(0, 0); // empty message is invalid
+	NUTS_TRUE(msg == NULL);
+	NUTS_TRUE(nn_errno() == EINVAL);
+}
+
+void
+test_msg_overflow(void)
+{
+	char *msg;
+	msg = nn_allocmsg((size_t)-1, 0); // this will overflow
+	NUTS_TRUE(msg == NULL);
+	NUTS_TRUE(nn_errno() == EINVAL);
+}
+
+void
+test_msg_bad_type(void)
+{
+	char *msg;
+	msg = nn_allocmsg(0, 1); // we only support message type 0
+	NUTS_TRUE(msg == NULL);
+	NUTS_TRUE(nn_errno() == EINVAL);
+}
+
+void
+test_msg_realloc(void)
+{
+	char *msg0;
+	char *msg1;
+	char *msg2;
+	char *msg3;
+
+	msg0 = nn_allocmsg(5, 0);
+	NUTS_TRUE(msg0 != NULL);
+
+	memcpy(msg0, "this", 5);
+
+	msg1 = nn_reallocmsg(msg0, 65536);
+	NUTS_TRUE(msg1 != NULL);
+	NUTS_TRUE(msg1 != msg0);
+	NUTS_MATCH(msg1, "this");
+
+	msg1[65000] = 'A';
+
+	msg2 = nn_reallocmsg(msg1, 5);
+	NUTS_TRUE(msg2 == msg1);
+
+	// test for overflow
+	msg3 = nn_reallocmsg(msg2, (size_t)-1);
+	NUTS_TRUE(msg3 == NULL);
+	NUTS_TRUE(nn_errno() == EINVAL);
+
+	nn_freemsg(msg2);
+}
+
+TEST_LIST = {
+	{ "alloc msg", test_msg_alloc },
+	{ "zero length", test_msg_zero_length },
+	{ "invalid type", test_msg_bad_type },
+	{ "overflow", test_msg_overflow },
+	{ "reallocate msg", test_msg_realloc },
+	{ NULL, NULL },
+};
diff --git a/src/compat/nanomsg/nn.c b/src/compat/nanomsg/nn.c
index 7c5d2383..0f975b2d 100644
--- a/src/compat/nanomsg/nn.c
+++ b/src/compat/nanomsg/nn.c
@@ -1,5 +1,5 @@
 //
-// Copyright 2018 Staysail Systems, Inc. <info@staysail.tech>
+// Copyright 2023 Staysail Systems, Inc. <info@staysail.tech>
 // Copyright 2018 Capitar IT Group BV <info@capitar.com>
 //
 // This software is supplied under the terms of the MIT License, a
@@ -237,7 +237,7 @@ nn_socket(int domain, int protocol)
 		return (-1);
 	}
 
-	// Legacy sockets have nodelay disabled.
+	// Legacy sockets have Nagle disabled.
 	(void) nng_socket_set_bool(sock, NNG_OPT_TCP_NODELAY, false);
 	return ((int) sock.id);
 }
@@ -298,7 +298,7 @@ nn_shutdown(int s, int ep)
 	// Socket is wired into the endpoint... so passing a bad endpoint
 	// ID can result in affecting the wrong socket.  But this requires
 	// a buggy application, and because we don't recycle endpoints
-	// until wrap, its unlikely to actually come up in practice.
+	// until wrap, it's unlikely to actually come up in practice.
 	// Note that listeners and dialers share the same namespace
 	// in the core, so we can close either one this way.
 
@@ -326,13 +326,12 @@ nn_allocmsg(size_t size, int type)
 	// So our "messages" from nn are really going to be nng messages
 	// but to make this work, we use a bit of headroom in the message
 	// to stash the message header.
-	if ((rv = nng_msg_alloc(&msg, size + (sizeof(msg)))) != 0) {
+	if ((rv = nng_msg_alloc(&msg, size)) != 0) {
 		nn_seterror(rv);
 		return (NULL);
 	}
 
-	// This counts on message bodies being aligned sensibly.
-	*(nng_msg **) (nng_msg_body(msg)) = msg;
+	nng_msg_insert(msg, &msg, sizeof(msg));
 
 	// We are counting on the implementation of nn_msg_trim to not
 	// reallocate the message but just to leave the prefix inplace.
@@ -367,14 +366,14 @@ nn_reallocmsg(void *ptr, size_t len)
 	msg = *(nng_msg **) (((char *) ptr) - sizeof(msg));
 
 	// We need to realloc the requested len, plus size for our header.
-	if ((rv = nng_msg_realloc(msg, len + sizeof(msg))) != 0) {
+	if ((rv = nng_msg_realloc(msg, len)) != 0) {
 		// We don't free the old message.  Code is free to cope
 		// as it sees fit.
 		nn_seterror(rv);
 		return (NULL);
 	}
 	// Stash the msg header pointer
-	*(nng_msg **) (nng_msg_body(msg)) = msg;
+	nng_msg_insert(msg, &msg, sizeof(msg));
 	nng_msg_trim(msg, sizeof(msg));
 	return (nng_msg_body(msg));
 }
@@ -433,7 +432,7 @@ int
 nn_recvmsg(int s, struct nn_msghdr *mh, int flags)
 {
 	int        rv;
-	nng_msg *  msg;
+	nng_msg   *msg;
 	size_t     len;
 	int        keep = 0;
 	nng_socket sid;
@@ -498,7 +497,7 @@ nn_recvmsg(int s, struct nn_msghdr *mh, int flags)
 	// If the caller has requested control information (header details),
 	// we grab it.
 	if (mh->msg_control != NULL) {
-		char *             cdata;
+		char              *cdata;
 		size_t             clen;
 		size_t             tlen;
 		size_t             spsz;
@@ -552,10 +551,10 @@ nn_recvmsg(int s, struct nn_msghdr *mh, int flags)
 int
 nn_sendmsg(int s, const struct nn_msghdr *mh, int flags)
 {
-	nng_msg *  msg  = NULL;
-	nng_msg *  cmsg = NULL;
+	nng_msg   *msg  = NULL;
+	nng_msg   *cmsg = NULL;
 	nng_socket sid;
-	char *     cdata;
+	char      *cdata;
 	int        keep = 0;
 	size_t     sz;
 	int        rv;
@@ -1152,7 +1151,7 @@ struct nn_cmsghdr *
 nn_cmsg_next(struct nn_msghdr *mh, struct nn_cmsghdr *first)
 {
 	size_t clen;
-	char * data;
+	char  *data;
 
 	// We only support SP headers, so there can be at most one header.
 	if (first != NULL) {
@@ -1201,8 +1200,8 @@ nn_device(int s1, int s2)
 #ifndef WIN32_LEAN_AND_MEAN
 #define WIN32_LEAN_AND_MEAN
 #endif
-#include <windows.h>
 #include <mswsock.h>
+#include <windows.h>
 #elif defined NNG_PLATFORM_POSIX
 #include <poll.h>
 #endif
@@ -1234,8 +1233,8 @@ nn_poll(struct nn_pollfd *fds, int nfds, int timeout)
 		if (fds[i].events & NN_POLLIN) {
 			nng_socket s;
 			s.id = fds[i].fd;
-			if ((rv = nng_socket_get_int(s, NNG_OPT_RECVFD, &fd)) !=
-			    0) {
+			if ((rv = nng_socket_get_int(
+			         s, NNG_OPT_RECVFD, &fd)) != 0) {
 				nn_seterror(rv);
 				NNI_FREE_STRUCTS(pfd, nfds * 2);
 				return (-1);
@@ -1251,8 +1250,8 @@ nn_poll(struct nn_pollfd *fds, int nfds, int timeout)
 		if (fds[i].events & NN_POLLOUT) {
 			nng_socket s;
 			s.id = fds[i].fd;
-			if ((rv = nng_socket_get_int(s, NNG_OPT_SENDFD, &fd)) !=
-			    0) {
+			if ((rv = nng_socket_get_int(
+			         s, NNG_OPT_SENDFD, &fd)) != 0) {
 				nn_seterror(rv);
 				NNI_FREE_STRUCTS(pfd, nfds * 2);
 				return (-1);