1/*
2 *  inet and unix socket functions for qemu
3 *
4 *  (c) 2008 Gerd Hoffmann <kraxel@redhat.com>
5 *
6 *  This program is free software; you can redistribute it and/or modify
7 *  it under the terms of the GNU General Public License as published by
8 *  the Free Software Foundation; under version 2 of the License.
9 *
10 *  This program is distributed in the hope that it will be useful,
11 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
12 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 *  GNU General Public License for more details.
14 */
15#include <stdio.h>
16#include <stdlib.h>
17#include <string.h>
18#include <ctype.h>
19#include <errno.h>
20#include <unistd.h>
21
22#include "qemu_socket.h"
23#include "qemu-common.h" /* for qemu_isdigit */
24
25#ifndef AI_ADDRCONFIG
26# define AI_ADDRCONFIG 0
27#endif
28
29static int sockets_debug = 0;
30static const int on=1, off=0;
31
32static int inet_getport(struct addrinfo *e)
33{
34    struct sockaddr_in *i4;
35    struct sockaddr_in6 *i6;
36
37    switch (e->ai_family) {
38    case PF_INET6:
39        i6 = (void*)e->ai_addr;
40        return ntohs(i6->sin6_port);
41    case PF_INET:
42        i4 = (void*)e->ai_addr;
43        return ntohs(i4->sin_port);
44    default:
45        return 0;
46    }
47}
48
49static void inet_setport(struct addrinfo *e, int port)
50{
51    struct sockaddr_in *i4;
52    struct sockaddr_in6 *i6;
53
54    switch (e->ai_family) {
55    case PF_INET6:
56        i6 = (void*)e->ai_addr;
57        i6->sin6_port = htons(port);
58        break;
59    case PF_INET:
60        i4 = (void*)e->ai_addr;
61        i4->sin_port = htons(port);
62        break;
63    }
64}
65
66static const char *inet_strfamily(int family)
67{
68    switch (family) {
69    case PF_INET6: return "ipv6";
70    case PF_INET:  return "ipv4";
71    case PF_UNIX:  return "unix";
72    }
73    return "????";
74}
75
76static void inet_print_addrinfo(const char *tag, struct addrinfo *res)
77{
78    struct addrinfo *e;
79    char uaddr[INET6_ADDRSTRLEN+1];
80    char uport[33];
81
82    for (e = res; e != NULL; e = e->ai_next) {
83        getnameinfo((struct sockaddr*)e->ai_addr,e->ai_addrlen,
84                    uaddr,INET6_ADDRSTRLEN,uport,32,
85                    NI_NUMERICHOST | NI_NUMERICSERV);
86        fprintf(stderr,"%s: getaddrinfo: family %s, host %s, port %s\n",
87                tag, inet_strfamily(e->ai_family), uaddr, uport);
88    }
89}
90
91int inet_listen(const char *str, char *ostr, int olen,
92                int socktype, int port_offset)
93{
94    struct addrinfo ai,*res,*e;
95    char addr[64];
96    char port[33];
97    char uaddr[INET6_ADDRSTRLEN+1];
98    char uport[33];
99    const char *opts, *h;
100    int slisten,rc,pos,to,try_next;
101
102    memset(&ai,0, sizeof(ai));
103    ai.ai_flags = AI_PASSIVE | AI_ADDRCONFIG;
104    ai.ai_family = PF_UNSPEC;
105    ai.ai_socktype = socktype;
106
107    /* parse address */
108    if (str[0] == ':') {
109        /* no host given */
110        addr[0] = '\0';
111        if (1 != sscanf(str,":%32[^,]%n",port,&pos)) {
112            fprintf(stderr, "%s: portonly parse error (%s)\n",
113                    __FUNCTION__, str);
114            return -1;
115        }
116    } else if (str[0] == '[') {
117        /* IPv6 addr */
118        if (2 != sscanf(str,"[%64[^]]]:%32[^,]%n",addr,port,&pos)) {
119            fprintf(stderr, "%s: ipv6 parse error (%s)\n",
120                    __FUNCTION__, str);
121            return -1;
122        }
123        ai.ai_family = PF_INET6;
124    } else if (qemu_isdigit(str[0])) {
125        /* IPv4 addr */
126        if (2 != sscanf(str,"%64[0-9.]:%32[^,]%n",addr,port,&pos)) {
127            fprintf(stderr, "%s: ipv4 parse error (%s)\n",
128                    __FUNCTION__, str);
129            return -1;
130        }
131        ai.ai_family = PF_INET;
132    } else {
133        /* hostname */
134        if (2 != sscanf(str,"%64[^:]:%32[^,]%n",addr,port,&pos)) {
135            fprintf(stderr, "%s: hostname parse error (%s)\n",
136                    __FUNCTION__, str);
137            return -1;
138        }
139    }
140
141    /* parse options */
142    opts = str + pos;
143    h = strstr(opts, ",to=");
144    to = h ? atoi(h+4) : 0;
145    if (strstr(opts, ",ipv4"))
146        ai.ai_family = PF_INET;
147    if (strstr(opts, ",ipv6"))
148        ai.ai_family = PF_INET6;
149
150    /* lookup */
151    if (port_offset)
152        snprintf(port, sizeof(port), "%d", atoi(port) + port_offset);
153    rc = getaddrinfo(strlen(addr) ? addr : NULL, port, &ai, &res);
154    if (rc != 0) {
155        fprintf(stderr,"%s: getaddrinfo(%s,%s): %s\n", __FUNCTION__,
156                addr, port, gai_strerror(rc));
157        return -1;
158    }
159    if (sockets_debug)
160        inet_print_addrinfo(__FUNCTION__, res);
161
162    /* create socket + bind */
163    for (e = res; e != NULL; e = e->ai_next) {
164        getnameinfo((struct sockaddr*)e->ai_addr,e->ai_addrlen,
165		        uaddr,INET6_ADDRSTRLEN,uport,32,
166		        NI_NUMERICHOST | NI_NUMERICSERV);
167        slisten = socket(e->ai_family, e->ai_socktype, e->ai_protocol);
168        if (slisten < 0) {
169            fprintf(stderr,"%s: socket(%s): %s\n", __FUNCTION__,
170                    inet_strfamily(e->ai_family), strerror(errno));
171            continue;
172        }
173
174        setsockopt(slisten,SOL_SOCKET,SO_REUSEADDR,(void*)&on,sizeof(on));
175#ifdef IPV6_V6ONLY
176        if (e->ai_family == PF_INET6) {
177            /* listen on both ipv4 and ipv6 */
178            setsockopt(slisten,IPPROTO_IPV6,IPV6_V6ONLY,(void*)&off,
179                sizeof(off));
180        }
181#endif
182
183        for (;;) {
184            if (bind(slisten, e->ai_addr, e->ai_addrlen) == 0) {
185                if (sockets_debug)
186                    fprintf(stderr,"%s: bind(%s,%s,%d): OK\n", __FUNCTION__,
187                        inet_strfamily(e->ai_family), uaddr, inet_getport(e));
188                goto listen;
189            }
190            try_next = to && (inet_getport(e) <= to + port_offset);
191            if (!try_next || sockets_debug)
192                fprintf(stderr,"%s: bind(%s,%s,%d): %s\n", __FUNCTION__,
193                        inet_strfamily(e->ai_family), uaddr, inet_getport(e),
194                        strerror(errno));
195            if (try_next) {
196                inet_setport(e, inet_getport(e) + 1);
197                continue;
198            }
199            break;
200        }
201        closesocket(slisten);
202    }
203    fprintf(stderr, "%s: FAILED\n", __FUNCTION__);
204    freeaddrinfo(res);
205    return -1;
206
207listen:
208    if (listen(slisten,1) != 0) {
209        perror("listen");
210        closesocket(slisten);
211        freeaddrinfo(res);
212        return -1;
213    }
214    if (ostr) {
215        if (e->ai_family == PF_INET6) {
216            snprintf(ostr, olen, "[%s]:%d%s", uaddr,
217                     inet_getport(e) - port_offset, opts);
218        } else {
219            snprintf(ostr, olen, "%s:%d%s", uaddr,
220                     inet_getport(e) - port_offset, opts);
221        }
222    }
223    freeaddrinfo(res);
224    return slisten;
225}
226
227int inet_connect(const char *str, int socktype)
228{
229    struct addrinfo ai,*res,*e;
230    char addr[64];
231    char port[33];
232    char uaddr[INET6_ADDRSTRLEN+1];
233    char uport[33];
234    int sock,rc;
235
236    memset(&ai,0, sizeof(ai));
237    ai.ai_flags = AI_CANONNAME | AI_ADDRCONFIG;
238    ai.ai_family = PF_UNSPEC;
239    ai.ai_socktype = socktype;
240
241    /* parse address */
242    if (str[0] == '[') {
243        /* IPv6 addr */
244        if (2 != sscanf(str,"[%64[^]]]:%32[^,]",addr,port)) {
245            fprintf(stderr, "%s: ipv6 parse error (%s)\n",
246                    __FUNCTION__, str);
247            return -1;
248        }
249        ai.ai_family = PF_INET6;
250    } else if (qemu_isdigit(str[0])) {
251        /* IPv4 addr */
252        if (2 != sscanf(str,"%64[0-9.]:%32[^,]",addr,port)) {
253            fprintf(stderr, "%s: ipv4 parse error (%s)\n",
254                    __FUNCTION__, str);
255            return -1;
256        }
257        ai.ai_family = PF_INET;
258    } else {
259        /* hostname */
260        if (2 != sscanf(str,"%64[^:]:%32[^,]",addr,port)) {
261            fprintf(stderr, "%s: hostname parse error (%s)\n",
262                    __FUNCTION__, str);
263            return -1;
264        }
265    }
266
267    /* parse options */
268    if (strstr(str, ",ipv4"))
269        ai.ai_family = PF_INET;
270    if (strstr(str, ",ipv6"))
271        ai.ai_family = PF_INET6;
272
273    /* lookup */
274    if (0 != (rc = getaddrinfo(addr, port, &ai, &res))) {
275        fprintf(stderr,"getaddrinfo(%s,%s): %s\n", gai_strerror(rc),
276                addr, port);
277	return -1;
278    }
279    if (sockets_debug)
280        inet_print_addrinfo(__FUNCTION__, res);
281
282    for (e = res; e != NULL; e = e->ai_next) {
283        if (getnameinfo((struct sockaddr*)e->ai_addr,e->ai_addrlen,
284                            uaddr,INET6_ADDRSTRLEN,uport,32,
285                            NI_NUMERICHOST | NI_NUMERICSERV) != 0) {
286            fprintf(stderr,"%s: getnameinfo: oops\n", __FUNCTION__);
287            continue;
288        }
289        sock = socket(e->ai_family, e->ai_socktype, e->ai_protocol);
290        if (sock < 0) {
291            fprintf(stderr,"%s: socket(%s): %s\n", __FUNCTION__,
292            inet_strfamily(e->ai_family), strerror(errno));
293            continue;
294        }
295        setsockopt(sock,SOL_SOCKET,SO_REUSEADDR,(void*)&on,sizeof(on));
296
297        /* connect to peer */
298        if (connect(sock,e->ai_addr,e->ai_addrlen) < 0) {
299            if (sockets_debug || NULL == e->ai_next)
300                fprintf(stderr, "%s: connect(%s,%s,%s,%s): %s\n", __FUNCTION__,
301                        inet_strfamily(e->ai_family),
302                        e->ai_canonname, uaddr, uport, strerror(errno));
303            closesocket(sock);
304            continue;
305        }
306        if (sockets_debug)
307            fprintf(stderr, "%s: connect(%s,%s,%s,%s): OK\n", __FUNCTION__,
308                    inet_strfamily(e->ai_family),
309                    e->ai_canonname, uaddr, uport);
310        freeaddrinfo(res);
311        return sock;
312    }
313    freeaddrinfo(res);
314    return -1;
315}
316
317#ifndef _WIN32
318
319int unix_listen(const char *str, char *ostr, int olen)
320{
321    struct sockaddr_un un;
322    char *path, *opts;
323    int sock, fd, len;
324
325    sock = socket(PF_UNIX, SOCK_STREAM, 0);
326    if (sock < 0) {
327        perror("socket(unix)");
328        return -1;
329    }
330
331    opts = strchr(str, ',');
332    if (opts) {
333        len = opts - str;
334        path = qemu_malloc(len+1);
335        snprintf(path, len+1, "%.*s", len, str);
336    } else
337        path = qemu_strdup(str);
338
339    memset(&un, 0, sizeof(un));
340    un.sun_family = AF_UNIX;
341    if (path && strlen(path)) {
342        snprintf(un.sun_path, sizeof(un.sun_path), "%s", path);
343    } else {
344        char *tmpdir = getenv("TMPDIR");
345        snprintf(un.sun_path, sizeof(un.sun_path), "%s/qemu-socket-XXXXXX",
346                 tmpdir ? tmpdir : "/tmp");
347        /*
348         * This dummy fd usage silences the mktemp() unsecure warning.
349         * Using mkstemp() doesn't make things more secure here
350         * though.  bind() complains about existing files, so we have
351         * to unlink first and thus re-open the race window.  The
352         * worst case possible is bind() failing, i.e. a DoS attack.
353         */
354        fd = mkstemp(un.sun_path); close(fd);
355    }
356    snprintf(ostr, olen, "%s%s", un.sun_path, opts ? opts : "");
357
358    unlink(un.sun_path);
359    if (bind(sock, (struct sockaddr*) &un, sizeof(un)) < 0) {
360        fprintf(stderr, "bind(unix:%s): %s\n", un.sun_path, strerror(errno));
361        goto err;
362    }
363    if (listen(sock, 1) < 0) {
364        fprintf(stderr, "listen(unix:%s): %s\n", un.sun_path, strerror(errno));
365        goto err;
366    }
367
368    if (sockets_debug)
369        fprintf(stderr, "bind(unix:%s): OK\n", un.sun_path);
370    qemu_free(path);
371    return sock;
372
373err:
374    qemu_free(path);
375    closesocket(sock);
376    return -1;
377}
378
379int unix_connect(const char *path)
380{
381    struct sockaddr_un un;
382    int sock;
383
384    sock = socket(PF_UNIX, SOCK_STREAM, 0);
385    if (sock < 0) {
386        perror("socket(unix)");
387        return -1;
388    }
389
390    memset(&un, 0, sizeof(un));
391    un.sun_family = AF_UNIX;
392    snprintf(un.sun_path, sizeof(un.sun_path), "%s", path);
393    if (connect(sock, (struct sockaddr*) &un, sizeof(un)) < 0) {
394        fprintf(stderr, "connect(unix:%s): %s\n", path, strerror(errno));
395	return -1;
396    }
397
398    if (sockets_debug)
399        fprintf(stderr, "connect(unix:%s): OK\n", path);
400    return sock;
401}
402
403#else
404
405int unix_listen(const char *path, char *ostr, int olen)
406{
407    fprintf(stderr, "unix sockets are not available on windows\n");
408    return -1;
409}
410
411int unix_connect(const char *path)
412{
413    fprintf(stderr, "unix sockets are not available on windows\n");
414    return -1;
415}
416
417#endif
418