sockets.c revision 774abe7b7e463436107545250aa573c99e246a86 
1/*
2 * Copyright (C) 2007 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include <stdio.h>
18#include <stdlib.h>
19#include <unistd.h>
20#include <errno.h>
21#include <string.h>
22#include <ctype.h>
23
24#include "sysdeps.h"
25
26#define  TRACE_TAG  TRACE_SOCKETS
27#include "adb.h"
28
29ADB_MUTEX_DEFINE( socket_list_lock );
30
31static void local_socket_close_locked(asocket *s);
32
33int sendfailmsg(int fd, const char *reason)
34{
35    char buf[9];
36    int len;
37    len = strlen(reason);
38    if(len > 0xffff) len = 0xffff;
39    snprintf(buf, sizeof buf, "FAIL%04x", len);
40    if(writex(fd, buf, 8)) return -1;
41    return writex(fd, reason, len);
42}
43
44//extern int online;
45
46static unsigned local_socket_next_id = 1;
47
48static asocket local_socket_list = {
49    .next = &local_socket_list,
50    .prev = &local_socket_list,
51};
52
53/* the the list of currently closing local sockets.
54** these have no peer anymore, but still packets to
55** write to their fd.
56*/
57static asocket local_socket_closing_list = {
58    .next = &local_socket_closing_list,
59    .prev = &local_socket_closing_list,
60};
61
62asocket *find_local_socket(unsigned id)
63{
64    asocket *s;
65    asocket *result = NULL;
66
67    adb_mutex_lock(&socket_list_lock);
68    for (s = local_socket_list.next; s != &local_socket_list; s = s->next) {
69        if (s->id == id) {
70            result = s;
71            break;
72        }
73    }
74    adb_mutex_unlock(&socket_list_lock);
75
76    return result;
77}
78
79static void
80insert_local_socket(asocket*  s, asocket*  list)
81{
82    s->next       = list;
83    s->prev       = s->next->prev;
84    s->prev->next = s;
85    s->next->prev = s;
86}
87
88
89void install_local_socket(asocket *s)
90{
91    adb_mutex_lock(&socket_list_lock);
92
93    s->id = local_socket_next_id++;
94    insert_local_socket(s, &local_socket_list);
95
96    adb_mutex_unlock(&socket_list_lock);
97}
98
99void remove_socket(asocket *s)
100{
101    // socket_list_lock should already be held
102    if (s->prev && s->next)
103    {
104        s->prev->next = s->next;
105        s->next->prev = s->prev;
106        s->next = 0;
107        s->prev = 0;
108        s->id = 0;
109    }
110}
111
112void close_all_sockets(atransport *t)
113{
114    asocket *s;
115
116        /* this is a little gross, but since s->close() *will* modify
117        ** the list out from under you, your options are limited.
118        */
119    adb_mutex_lock(&socket_list_lock);
120restart:
121    for(s = local_socket_list.next; s != &local_socket_list; s = s->next){
122        if(s->transport == t || (s->peer && s->peer->transport == t)) {
123            local_socket_close_locked(s);
124            goto restart;
125        }
126    }
127    adb_mutex_unlock(&socket_list_lock);
128}
129
130static int local_socket_enqueue(asocket *s, apacket *p)
131{
132    D("LS(%d): enqueue %d\n", s->id, p->len);
133
134    p->ptr = p->data;
135
136        /* if there is already data queue'd, we will receive
137        ** events when it's time to write.  just add this to
138        ** the tail
139        */
140    if(s->pkt_first) {
141        goto enqueue;
142    }
143
144        /* write as much as we can, until we
145        ** would block or there is an error/eof
146        */
147    while(p->len > 0) {
148        int r = adb_write(s->fd, p->ptr, p->len);
149        if(r > 0) {
150            p->len -= r;
151            p->ptr += r;
152            continue;
153        }
154        if((r == 0) || (errno != EAGAIN)) {
155            D( "LS(%d): not ready, errno=%d: %s\n", s->id, errno, strerror(errno) );
156            s->close(s);
157            return 1; /* not ready (error) */
158        } else {
159            break;
160        }
161    }
162
163    if(p->len == 0) {
164        put_apacket(p);
165        return 0; /* ready for more data */
166    }
167
168enqueue:
169    p->next = 0;
170    if(s->pkt_first) {
171        s->pkt_last->next = p;
172    } else {
173        s->pkt_first = p;
174    }
175    s->pkt_last = p;
176
177        /* make sure we are notified when we can drain the queue */
178    fdevent_add(&s->fde, FDE_WRITE);
179
180    return 1; /* not ready (backlog) */
181}
182
183static void local_socket_ready(asocket *s)
184{
185        /* far side is ready for data, pay attention to
186           readable events */
187    fdevent_add(&s->fde, FDE_READ);
188//    D("LS(%d): ready()\n", s->id);
189}
190
191static void local_socket_close(asocket *s)
192{
193    adb_mutex_lock(&socket_list_lock);
194    local_socket_close_locked(s);
195    adb_mutex_unlock(&socket_list_lock);
196}
197
198// be sure to hold the socket list lock when calling this
199static void local_socket_destroy(asocket  *s)
200{
201    apacket *p, *n;
202
203        /* IMPORTANT: the remove closes the fd
204        ** that belongs to this socket
205        */
206    fdevent_remove(&s->fde);
207
208        /* dispose of any unwritten data */
209    for(p = s->pkt_first; p; p = n) {
210        D("LS(%d): discarding %d bytes\n", s->id, p->len);
211        n = p->next;
212        put_apacket(p);
213    }
214    remove_socket(s);
215    free(s);
216}
217
218
219static void local_socket_close_locked(asocket *s)
220{
221    if(s->peer) {
222        s->peer->peer = 0;
223        // tweak to avoid deadlock
224        if (s->peer->close == local_socket_close) {
225            local_socket_close_locked(s->peer);
226        } else {
227            s->peer->close(s->peer);
228        }
229        s->peer = 0;
230    }
231
232        /* If we are already closing, or if there are no
233        ** pending packets, destroy immediately
234        */
235    if (s->closing || s->pkt_first == NULL) {
236        int   id = s->id;
237        local_socket_destroy(s);
238        D("LS(%d): closed\n", id);
239        return;
240    }
241
242        /* otherwise, put on the closing list
243        */
244    D("LS(%d): closing\n", s->id);
245    s->closing = 1;
246    fdevent_del(&s->fde, FDE_READ);
247    remove_socket(s);
248    insert_local_socket(s, &local_socket_closing_list);
249}
250
251static void local_socket_event_func(int fd, unsigned ev, void *_s)
252{
253    asocket *s = _s;
254
255    /* put the FDE_WRITE processing before the FDE_READ
256    ** in order to simplify the code.
257    */
258    if(ev & FDE_WRITE){
259        apacket *p;
260
261        while((p = s->pkt_first) != 0) {
262            while(p->len > 0) {
263                int r = adb_write(fd, p->ptr, p->len);
264                if(r > 0) {
265                    p->ptr += r;
266                    p->len -= r;
267                    continue;
268                }
269                if(r < 0) {
270                    /* returning here is ok because FDE_READ will
271                    ** be processed in the next iteration loop
272                    */
273                    if(errno == EAGAIN) return;
274                    if(errno == EINTR) continue;
275                }
276                s->close(s);
277                return;
278            }
279
280            if(p->len == 0) {
281                s->pkt_first = p->next;
282                if(s->pkt_first == 0) s->pkt_last = 0;
283                put_apacket(p);
284            }
285        }
286
287            /* if we sent the last packet of a closing socket,
288            ** we can now destroy it.
289            */
290        if (s->closing) {
291            s->close(s);
292            return;
293        }
294
295            /* no more packets queued, so we can ignore
296            ** writable events again and tell our peer
297            ** to resume writing
298            */
299        fdevent_del(&s->fde, FDE_WRITE);
300        s->peer->ready(s->peer);
301    }
302
303
304    if(ev & FDE_READ){
305        apacket *p = get_apacket();
306        unsigned char *x = p->data;
307        size_t avail = MAX_PAYLOAD;
308        int r;
309        int is_eof = 0;
310
311        while(avail > 0) {
312            r = adb_read(fd, x, avail);
313            if(r > 0) {
314                avail -= r;
315                x += r;
316                continue;
317            }
318            if(r < 0) {
319                if(errno == EAGAIN) break;
320                if(errno == EINTR) continue;
321            }
322
323                /* r = 0 or unhandled error */
324            is_eof = 1;
325            break;
326        }
327
328        if((avail == MAX_PAYLOAD) || (s->peer == 0)) {
329            put_apacket(p);
330        } else {
331            p->len = MAX_PAYLOAD - avail;
332
333            r = s->peer->enqueue(s->peer, p);
334
335            if(r < 0) {
336                    /* error return means they closed us as a side-effect
337                    ** and we must return immediately.
338                    **
339                    ** note that if we still have buffered packets, the
340                    ** socket will be placed on the closing socket list.
341                    ** this handler function will be called again
342                    ** to process FDE_WRITE events.
343                    */
344                return;
345            }
346
347            if(r > 0) {
348                    /* if the remote cannot accept further events,
349                    ** we disable notification of READs.  They'll
350                    ** be enabled again when we get a call to ready()
351                    */
352                fdevent_del(&s->fde, FDE_READ);
353            }
354        }
355
356        if(is_eof) {
357            s->close(s);
358        }
359    }
360
361    if(ev & FDE_ERROR){
362            /* this should be caught be the next read or write
363            ** catching it here means we may skip the last few
364            ** bytes of readable data.
365            */
366//        s->close(s);
367        return;
368    }
369}
370
371asocket *create_local_socket(int fd)
372{
373    asocket *s = calloc(1, sizeof(asocket));
374    if (s == NULL) fatal("cannot allocate socket");
375    install_local_socket(s);
376    s->fd = fd;
377    s->enqueue = local_socket_enqueue;
378    s->ready = local_socket_ready;
379    s->close = local_socket_close;
380
381    fdevent_install(&s->fde, fd, local_socket_event_func, s);
382/*    fdevent_add(&s->fde, FDE_ERROR); */
383    //fprintf(stderr, "Created local socket in create_local_socket \n");
384    D("LS(%d): created (fd=%d)\n", s->id, s->fd);
385    return s;
386}
387
388asocket *create_local_service_socket(const char *name)
389{
390    asocket *s;
391    int fd;
392
393#if !ADB_HOST
394    if (!strcmp(name,"jdwp")) {
395        return create_jdwp_service_socket();
396    }
397    if (!strcmp(name,"track-jdwp")) {
398        return create_jdwp_tracker_service_socket();
399    }
400#endif
401    fd = service_to_fd(name);
402    if(fd < 0) return 0;
403
404    s = create_local_socket(fd);
405    D("LS(%d): bound to '%s'\n", s->id, name);
406    return s;
407}
408
409#if ADB_HOST
410static asocket *create_host_service_socket(const char *name, const char* serial)
411{
412    asocket *s;
413
414    s = host_service_to_socket(name, serial);
415
416    if (s != NULL) {
417        D("LS(%d) bound to '%s'\n", s->id, name);
418        return s;
419    }
420
421    return s;
422}
423#endif /* ADB_HOST */
424
425/* a Remote socket is used to send/receive data to/from a given transport object
426** it needs to be closed when the transport is forcibly destroyed by the user
427*/
428typedef struct aremotesocket {
429    asocket      socket;
430    adisconnect  disconnect;
431} aremotesocket;
432
433static int remote_socket_enqueue(asocket *s, apacket *p)
434{
435    D("Calling remote_socket_enqueue\n");
436    p->msg.command = A_WRTE;
437    p->msg.arg0 = s->peer->id;
438    p->msg.arg1 = s->id;
439    p->msg.data_length = p->len;
440    send_packet(p, s->transport);
441    return 1;
442}
443
444static void remote_socket_ready(asocket *s)
445{
446    D("Calling remote_socket_ready\n");
447    apacket *p = get_apacket();
448    p->msg.command = A_OKAY;
449    p->msg.arg0 = s->peer->id;
450    p->msg.arg1 = s->id;
451    send_packet(p, s->transport);
452}
453
454static void remote_socket_close(asocket *s)
455{
456    D("Calling remote_socket_close\n");
457    apacket *p = get_apacket();
458    p->msg.command = A_CLSE;
459    if(s->peer) {
460        p->msg.arg0 = s->peer->id;
461        s->peer->peer = 0;
462        s->peer->close(s->peer);
463    }
464    p->msg.arg1 = s->id;
465    send_packet(p, s->transport);
466    D("RS(%d): closed\n", s->id);
467    remove_transport_disconnect( s->transport, &((aremotesocket*)s)->disconnect );
468    free(s);
469}
470
471static void remote_socket_disconnect(void*  _s, atransport*  t)
472{
473    asocket*  s    = _s;
474    asocket*  peer = s->peer;
475
476    D("remote_socket_disconnect RS(%d)\n", s->id);
477    if (peer) {
478        peer->peer = NULL;
479        peer->close(peer);
480    }
481    remove_transport_disconnect( s->transport, &((aremotesocket*)s)->disconnect );
482    free(s);
483}
484
485asocket *create_remote_socket(unsigned id, atransport *t)
486{
487    asocket *s = calloc(1, sizeof(aremotesocket));
488    adisconnect*  dis = &((aremotesocket*)s)->disconnect;
489
490    if (s == NULL) fatal("cannot allocate socket");
491    s->id = id;
492    s->enqueue = remote_socket_enqueue;
493    s->ready = remote_socket_ready;
494    s->close = remote_socket_close;
495    s->transport = t;
496
497    dis->func   = remote_socket_disconnect;
498    dis->opaque = s;
499    add_transport_disconnect( t, dis );
500    D("RS(%d): created\n", s->id);
501    return s;
502}
503
504void connect_to_remote(asocket *s, const char *destination)
505{
506    D("Connect_to_remote call \n");
507    apacket *p = get_apacket();
508    int len = strlen(destination) + 1;
509
510    if(len > (MAX_PAYLOAD-1)) {
511        fatal("destination oversized");
512    }
513
514    D("LS(%d): connect('%s')\n", s->id, destination);
515    p->msg.command = A_OPEN;
516    p->msg.arg0 = s->id;
517    p->msg.data_length = len;
518    strcpy((char*) p->data, destination);
519    send_packet(p, s->transport);
520}
521
522
523/* this is used by magic sockets to rig local sockets to
524   send the go-ahead message when they connect */
525static void local_socket_ready_notify(asocket *s)
526{
527    s->ready = local_socket_ready;
528    s->close = local_socket_close;
529    adb_write(s->fd, "OKAY", 4);
530    s->ready(s);
531}
532
533/* this is used by magic sockets to rig local sockets to
534   send the failure message if they are closed before
535   connected (to avoid closing them without a status message) */
536static void local_socket_close_notify(asocket *s)
537{
538    s->ready = local_socket_ready;
539    s->close = local_socket_close;
540    sendfailmsg(s->fd, "closed");
541    s->close(s);
542}
543
544unsigned unhex(unsigned char *s, int len)
545{
546    unsigned n = 0, c;
547
548    while(len-- > 0) {
549        switch((c = *s++)) {
550        case '0': case '1': case '2':
551        case '3': case '4': case '5':
552        case '6': case '7': case '8':
553        case '9':
554            c -= '0';
555            break;
556        case 'a': case 'b': case 'c':
557        case 'd': case 'e': case 'f':
558            c = c - 'a' + 10;
559            break;
560        case 'A': case 'B': case 'C':
561        case 'D': case 'E': case 'F':
562            c = c - 'A' + 10;
563            break;
564        default:
565            return 0xffffffff;
566        }
567
568        n = (n << 4) | c;
569    }
570
571    return n;
572}
573
574static int smart_socket_enqueue(asocket *s, apacket *p)
575{
576    unsigned len;
577#if ADB_HOST
578    char *service = NULL;
579    char* serial = NULL;
580    transport_type ttype = kTransportAny;
581#endif
582
583    D("SS(%d): enqueue %d\n", s->id, p->len);
584
585    if(s->pkt_first == 0) {
586        s->pkt_first = p;
587        s->pkt_last = p;
588    } else {
589        if((s->pkt_first->len + p->len) > MAX_PAYLOAD) {
590            D("SS(%d): overflow\n", s->id);
591            put_apacket(p);
592            goto fail;
593        }
594
595        memcpy(s->pkt_first->data + s->pkt_first->len,
596               p->data, p->len);
597        s->pkt_first->len += p->len;
598        put_apacket(p);
599
600        p = s->pkt_first;
601    }
602
603        /* don't bother if we can't decode the length */
604    if(p->len < 4) return 0;
605
606    len = unhex(p->data, 4);
607    if((len < 1) ||  (len > 1024)) {
608        D("SS(%d): bad size (%d)\n", s->id, len);
609        goto fail;
610    }
611
612    D("SS(%d): len is %d\n", s->id, len );
613        /* can't do anything until we have the full header */
614    if((len + 4) > p->len) {
615        D("SS(%d): waiting for %d more bytes\n", s->id, len+4 - p->len);
616        return 0;
617    }
618
619    p->data[len + 4] = 0;
620
621    D("SS(%d): '%s'\n", s->id, (char*) (p->data + 4));
622
623#if ADB_HOST
624    service = (char *)p->data + 4;
625    if(!strncmp(service, "host-serial:", strlen("host-serial:"))) {
626        char* serial_end;
627        service += strlen("host-serial:");
628
629        // serial number should follow "host:"
630        serial_end = strchr(service, ':');
631        if (serial_end) {
632            *serial_end = 0; // terminate string
633            serial = service;
634            service = serial_end + 1;
635        }
636    } else if (!strncmp(service, "host-usb:", strlen("host-usb:"))) {
637        ttype = kTransportUsb;
638        service += strlen("host-usb:");
639    } else if (!strncmp(service, "host-local:", strlen("host-local:"))) {
640        ttype = kTransportLocal;
641        service += strlen("host-local:");
642    } else if (!strncmp(service, "host:", strlen("host:"))) {
643        ttype = kTransportAny;
644        service += strlen("host:");
645    } else {
646        service = NULL;
647    }
648
649    if (service) {
650        asocket *s2;
651
652            /* some requests are handled immediately -- in that
653            ** case the handle_host_request() routine has sent
654            ** the OKAY or FAIL message and all we have to do
655            ** is clean up.
656            */
657        if(handle_host_request(service, ttype, serial, s->peer->fd, s) == 0) {
658                /* XXX fail message? */
659            D( "SS(%d): handled host service '%s'\n", s->id, service );
660            goto fail;
661        }
662        if (!strncmp(service, "transport", strlen("transport"))) {
663            D( "SS(%d): okay transport\n", s->id );
664            p->len = 0;
665            return 0;
666        }
667
668            /* try to find a local service with this name.
669            ** if no such service exists, we'll fail out
670            ** and tear down here.
671            */
672        s2 = create_host_service_socket(service, serial);
673        if(s2 == 0) {
674            D( "SS(%d): couldn't create host service '%s'\n", s->id, service );
675            sendfailmsg(s->peer->fd, "unknown host service");
676            goto fail;
677        }
678
679            /* we've connected to a local host service,
680            ** so we make our peer back into a regular
681            ** local socket and bind it to the new local
682            ** service socket, acknowledge the successful
683            ** connection, and close this smart socket now
684            ** that its work is done.
685            */
686        adb_write(s->peer->fd, "OKAY", 4);
687
688        s->peer->ready = local_socket_ready;
689        s->peer->close = local_socket_close;
690        s->peer->peer = s2;
691        s2->peer = s->peer;
692        s->peer = 0;
693        D( "SS(%d): okay\n", s->id );
694        s->close(s);
695
696            /* initial state is "ready" */
697        s2->ready(s2);
698        return 0;
699    }
700#else /* !ADB_HOST */
701    if (s->transport == NULL) {
702        char* error_string = "unknown failure";
703        s->transport = acquire_one_transport (CS_ANY,
704                kTransportAny, NULL, &error_string);
705
706        if (s->transport == NULL) {
707            sendfailmsg(s->peer->fd, error_string);
708            goto fail;
709        }
710    }
711#endif
712
713    if(!(s->transport) || (s->transport->connection_state == CS_OFFLINE)) {
714           /* if there's no remote we fail the connection
715            ** right here and terminate it
716            */
717        sendfailmsg(s->peer->fd, "device offline (x)");
718        goto fail;
719    }
720
721
722        /* instrument our peer to pass the success or fail
723        ** message back once it connects or closes, then
724        ** detach from it, request the connection, and
725        ** tear down
726        */
727    s->peer->ready = local_socket_ready_notify;
728    s->peer->close = local_socket_close_notify;
729    s->peer->peer = 0;
730        /* give him our transport and upref it */
731    s->peer->transport = s->transport;
732
733    connect_to_remote(s->peer, (char*) (p->data + 4));
734    s->peer = 0;
735    s->close(s);
736    return 1;
737
738fail:
739        /* we're going to close our peer as a side-effect, so
740        ** return -1 to signal that state to the local socket
741        ** who is enqueueing against us
742        */
743    s->close(s);
744    return -1;
745}
746
747static void smart_socket_ready(asocket *s)
748{
749    D("SS(%d): ready\n", s->id);
750}
751
752static void smart_socket_close(asocket *s)
753{
754    D("SS(%d): closed\n", s->id);
755    if(s->pkt_first){
756        put_apacket(s->pkt_first);
757    }
758    if(s->peer) {
759        s->peer->peer = 0;
760        s->peer->close(s->peer);
761        s->peer = 0;
762    }
763    free(s);
764}
765
766asocket *create_smart_socket(void (*action_cb)(asocket *s, const char *act))
767{
768    D("Creating smart socket \n");
769    asocket *s = calloc(1, sizeof(asocket));
770    if (s == NULL) fatal("cannot allocate socket");
771    s->enqueue = smart_socket_enqueue;
772    s->ready = smart_socket_ready;
773    s->close = smart_socket_close;
774    s->extra = action_cb;
775
776    D("SS(%d): created %p\n", s->id, action_cb);
777    return s;
778}
779
780void smart_socket_action(asocket *s, const char *act)
781{
782
783}
784
785void connect_to_smartsocket(asocket *s)
786{
787    D("Connecting to smart socket \n");
788    asocket *ss = create_smart_socket(smart_socket_action);
789    s->peer = ss;
790    ss->peer = s;
791    s->ready(s);
792}
793