aboutgitcodebugslistschat
path: root/qemu/0001-net-Allow-also-UNIX-domain-sockets-to-be-used-as-net.patch
blob: ef005260564b25776b758a70ea646cff7028de45 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
From 8876676bbdb108f51c372d1347dec1382078d702 Mon Sep 17 00:00:00 2001
From: Stefano Brivio <sbrivio@redhat.com>
Date: Wed, 17 Mar 2021 10:33:22 +0100
Subject: [PATCH 1/2] net: Allow also UNIX domain sockets to be used as -netdev
 socket

It has lower overhead compared to TCP, doesn't need a free port
and the adaptation is trivial.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
---
 net/socket.c    | 93 +++++++++++++++++++++++++++++++++++++++++--------
 qemu-options.hx | 12 +++----
 2 files changed, 84 insertions(+), 21 deletions(-)

diff --git a/net/socket.c b/net/socket.c
index c0de10c0c0..9d06953983 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -528,27 +528,62 @@ static int net_socket_listen_init(NetClientState *peer,
 {
     NetClientState *nc;
     NetSocketState *s;
-    struct sockaddr_in saddr;
-    int fd, ret;
+    struct sockaddr_storage saddr;
+    struct sockaddr_in *saddr_in = (struct sockaddr_in *)&saddr;
+    struct sockaddr_un *saddr_un = (struct sockaddr_un *)&saddr;
+    size_t saddr_size;
+    int fd, ret, pf;
     NetdevSocketOptions *stored;
 
-    if (parse_host_port(&saddr, host_str, errp) < 0) {
-        return -1;
+#ifndef WIN32
+    if (strchr(host_str, ':')) {
+#endif
+        if (parse_host_port(saddr_in, host_str, errp) < 0)
+            return -1;
+
+        pf = PF_INET;
+        saddr_size = sizeof(*saddr_in);
+#ifndef WIN32
+    } else {
+        struct stat sb;
+
+        if (stat(host_str, &sb) == -1) {
+            error_setg_errno(errp, errno, "can't stat socket path");
+            return -1;
+        }
+
+        if ((sb.st_mode & S_IFMT) != S_IFSOCK) {
+            error_setg_errno(errp, errno, "path provided is not a socket");
+            return -1;
+        }
+
+        saddr_un->sun_family = PF_UNIX;
+        strncpy(saddr_un->sun_path, host_str, sizeof(saddr_un->sun_path));
+
+        pf = PF_UNIX;
+        saddr_size = sizeof(*saddr_un);
     }
+#endif /* !WIN32 */
 
-    fd = qemu_socket(PF_INET, SOCK_STREAM, 0);
+    fd = qemu_socket(pf, SOCK_STREAM, 0);
     if (fd < 0) {
         error_setg_errno(errp, errno, "can't create stream socket");
         return -1;
     }
     qemu_set_nonblock(fd);
 
-    socket_set_fast_reuse(fd);
+    if (pf == PF_INET)
+        socket_set_fast_reuse(fd);
 
-    ret = bind(fd, (struct sockaddr *)&saddr, sizeof(saddr));
+    ret = bind(fd, (struct sockaddr *)&saddr, saddr_size);
     if (ret < 0) {
-        error_setg_errno(errp, errno, "can't bind ip=%s to socket",
-                         inet_ntoa(saddr.sin_addr));
+        if (pf == PF_INET)
+            error_setg_errno(errp, errno, "can't bind ip=%s to socket",
+                             inet_ntoa(saddr_in->sin_addr));
+        else if (pf == PF_UNIX)
+            error_setg_errno(errp, errno, "can't create socket with path: %s",
+                             host_str);
+
         closesocket(fd);
         return -1;
     }
@@ -586,15 +621,43 @@ static int net_socket_connect_init(NetClientState *peer,
                                    Error **errp)
 {
     NetSocketState *s;
-    int fd, connected, ret;
-    struct sockaddr_in saddr;
+    int fd, connected, ret, pf;
+    struct sockaddr_storage saddr;
+    size_t saddr_size;
     NetdevSocketOptions *stored;
 
-    if (parse_host_port(&saddr, host_str, errp) < 0) {
-        return -1;
+#ifndef WIN32
+    if (strchr(host_str, ':')) {
+#endif
+        if (parse_host_port((struct sockaddr_in *)&saddr, host_str, errp) < 0)
+            return -1;
+
+        pf = PF_INET;
+        saddr_size = sizeof(struct sockaddr_in);
+#ifndef WIN32
+    } else {
+        struct sockaddr_un *saddr_un = (struct sockaddr_un *)&saddr;
+        struct stat sb;
+
+        if (stat(host_str, &sb) == -1) {
+            error_setg_errno(errp, errno, "can't stat socket path");
+            return -1;
+        }
+
+        if ((sb.st_mode & S_IFMT) != S_IFSOCK) {
+            error_setg_errno(errp, errno, "provided path is not a socket");
+            return -1;
+        }
+
+        saddr_un->sun_family = PF_UNIX;
+        strncpy(saddr_un->sun_path, host_str, sizeof(saddr_un->sun_path));
+
+        pf = PF_UNIX;
+        saddr_size = sizeof(struct sockaddr_un);
     }
+#endif /* !WIN32 */
 
-    fd = qemu_socket(PF_INET, SOCK_STREAM, 0);
+    fd = qemu_socket(pf, SOCK_STREAM, 0);
     if (fd < 0) {
         error_setg_errno(errp, errno, "can't create stream socket");
         return -1;
@@ -603,7 +666,7 @@ static int net_socket_connect_init(NetClientState *peer,
 
     connected = 0;
     for(;;) {
-        ret = connect(fd, (struct sockaddr *)&saddr, sizeof(saddr));
+        ret = connect(fd, (struct sockaddr *)&saddr, saddr_size);
         if (ret < 0) {
             if (errno == EINTR || errno == EWOULDBLOCK) {
                 /* continue */
diff --git a/qemu-options.hx b/qemu-options.hx
index fe83ea09b2..b41351a54e 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -2836,13 +2836,13 @@ SRST
         #connect a TAP device to bridge qemubr0
         |qemu_system| linux.img -netdev bridge,br=qemubr0,id=n1 -device virtio-net,netdev=n1
 
-``-netdev socket,id=id[,fd=h][,listen=[host]:port][,connect=host:port]``
+``-netdev socket,id=id[,fd=h][,listen=[host]:port|path][,connect=host:port|path]``
     This host network backend can be used to connect the guest's network
-    to another QEMU virtual machine using a TCP socket connection. If
-    ``listen`` is specified, QEMU waits for incoming connections on port
-    (host is optional). ``connect`` is used to connect to another QEMU
-    instance using the ``listen`` option. ``fd``\ =h specifies an
-    already opened TCP socket.
+    to another QEMU virtual machine using a TCP or a UNIX domain socket
+    connection. If ``listen`` is specified, QEMU waits for incoming
+    connections on port (host is optional), or on path. ``connect`` is used
+    to connect to another QEMU instance using the ``listen`` option.
+    ``fd``\ =h specifies an already opened TCP or UNIX domain socket.
 
     Example:
 
-- 
2.28.0