sockets.c revision 0e7c4274c687446dbe30a814278d7a6b99da8c4e 
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
230        /* If we are already closing, or if there are no
231        ** pending packets, destroy immediately
232        */
233    if (s->closing || s->pkt_first == NULL) {
234        int   id = s->id;
235        local_socket_destroy(s);
236        D("LS(%d): closed\n", id);
237        return;
238    }
239
240        /* otherwise, put on the closing list
241        */
242    D("LS(%d): closing\n", s->id);
243    s->closing = 1;
244    fdevent_del(&s->fde, FDE_READ);
245    remove_socket(s);
246    insert_local_socket(s, &local_socket_closing_list);
247}
248
249static void local_socket_event_func(int fd, unsigned ev, void *_s)
250{
251    asocket *s = _s;
252
253    /* put the FDE_WRITE processing before the FDE_READ
254    ** in order to simplify the code.
255    */
256    if(ev & FDE_WRITE){
257        apacket *p;
258
259        while((p = s->pkt_first) != 0) {
260            while(p->len > 0) {
261                int r = adb_write(fd, p->ptr, p->len);
262                if(r > 0) {
263                    p->ptr += r;
264                    p->len -= r;
265                    continue;
266                }
267                if(r < 0) {
268                    /* returning here is ok because FDE_READ will
269                    ** be processed in the next iteration loop
270                    */
271                    if(errno == EAGAIN) return;
272                    if(errno == EINTR) continue;
273                }
274                s->close(s);
275                return;
276            }
277
278            if(p->len == 0) {
279                s->pkt_first = p->next;
280                if(s->pkt_first == 0) s->pkt_last = 0;
281                put_apacket(p);
282            }
283        }
284
285            /* if we sent the last packet of a closing socket,
286            ** we can now destroy it.
287            */
288        if (s->closing) {
289            s->close(s);
290            return;
291        }
292
293            /* no more packets queued, so we can ignore
294            ** writable events again and tell our peer
295            ** to resume writing
296            */
297        fdevent_del(&s->fde, FDE_WRITE);
298        s->peer->ready(s->peer);
299    }
300
301
302    if(ev & FDE_READ){
303        apacket *p = get_apacket();
304        unsigned char *x = p->data;
305        size_t avail = MAX_PAYLOAD;
306        int r;
307        int is_eof = 0;
308
309        while(avail > 0) {
310            r = adb_read(fd, x, avail);
311            if(r > 0) {
312                avail -= r;
313                x += r;
314                continue;
315            }
316            if(r < 0) {
317                if(errno == EAGAIN) break;
318                if(errno == EINTR) continue;
319            }
320
321                /* r = 0 or unhandled error */
322            is_eof = 1;
323            break;
324        }
325
326        if((avail == MAX_PAYLOAD) || (s->peer == 0)) {
327            put_apacket(p);
328        } else {
329            p->len = MAX_PAYLOAD - avail;
330
331            r = s->peer->enqueue(s->peer, p);
332
333            if(r < 0) {
334                    /* error return means they closed us as a side-effect
335                    ** and we must return immediately.
336                    **
337                    ** note that if we still have buffered packets, the
338                    ** socket will be placed on the closing socket list.
339                    ** this handler function will be called again
340                    ** to process FDE_WRITE events.
341                    */
342                return;
343            }
344
345            if(r > 0) {
346                    /* if the remote cannot accept further events,
347                    ** we disable notification of READs.  They'll
348                    ** be enabled again when we get a call to ready()
349                    */
350                fdevent_del(&s->fde, FDE_READ);
351            }
352        }
353
354        if(is_eof) {
355            s->close(s);
356        }
357    }
358
359    if(ev & FDE_ERROR){
360            /* this should be caught be the next read or write
361            ** catching it here means we may skip the last few
362            ** bytes of readable data.
363            */
364//        s->close(s);
365        return;
366    }
367}
368
369asocket *create_local_socket(int fd)
370{
371    asocket *s = calloc(1, sizeof(asocket));
372    if (s == NULL) fatal("cannot allocate socket");
373    install_local_socket(s);
374    s->fd = fd;
375    s->enqueue = local_socket_enqueue;
376    s->ready = local_socket_ready;
377    s->close = local_socket_close;
378
379    fdevent_install(&s->fde, fd, local_socket_event_func, s);
380/*    fdevent_add(&s->fde, FDE_ERROR); */
381    //fprintf(stderr, "Created local socket in create_local_socket \n");
382    D("LS(%d): created (fd=%d)\n", s->id, s->fd);
383    return s;
384}
385
386asocket *create_local_service_socket(const char *name)
387{
388    asocket *s;
389    int fd;
390
391#if !ADB_HOST
392    if (!strcmp(name,"jdwp")) {
393        return create_jdwp_service_socket();
394    }
395    if (!strcmp(name,"track-jdwp")) {
396        return create_jdwp_tracker_service_socket();
397    }
398#endif
399    fd = service_to_fd(name);
400    if(fd < 0) return 0;
401
402    s = create_local_socket(fd);
403    D("LS(%d): bound to '%s'\n", s->id, name);
404    return s;
405}
406
407#if ADB_HOST
408static asocket *create_host_service_socket(const char *name, const char* serial)
409{
410    asocket *s;
411
412    s = host_service_to_socket(name, serial);
413
414    if (s != NULL) {
415        D("LS(%d) bound to '%s'\n", s->id, name);
416        return s;
417    }
418
419    return s;
420}
421#endif /* ADB_HOST */
422
423/* a Remote socket is used to send/receive data to/from a given transport object
424** it needs to be closed when the transport is forcibly destroyed by the user
425*/
426typedef struct aremotesocket {
427    asocket      socket;
428    adisconnect  disconnect;
429} aremotesocket;
430
431static int remote_socket_enqueue(asocket *s, apacket *p)
432{
433    D("Calling remote_socket_enqueue\n");
434    p->msg.command = A_WRTE;
435    p->msg.arg0 = s->peer->id;
436    p->msg.arg1 = s->id;
437    p->msg.data_length = p->len;
438    send_packet(p, s->transport);
439    return 1;
440}
441
442static void remote_socket_ready(asocket *s)
443{
444    D("Calling remote_socket_ready\n");
445    apacket *p = get_apacket();
446    p->msg.command = A_OKAY;
447    p->msg.arg0 = s->peer->id;
448    p->msg.arg1 = s->id;
449    send_packet(p, s->transport);
450}
451
452static void remote_socket_close(asocket *s)
453{
454    D("Calling remote_socket_close\n");
455    apacket *p = get_apacket();
456    p->msg.command = A_CLSE;
457    if(s->peer) {
458        p->msg.arg0 = s->peer->id;
459        s->peer->peer = 0;
460        s->peer->close(s->peer);
461    }
462    p->msg.arg1 = s->id;
463    send_packet(p, s->transport);
464    D("RS(%d): closed\n", s->id);
465    remove_transport_disconnect( s->transport, &((aremotesocket*)s)->disconnect );
466    free(s);
467}
468
469static void remote_socket_disconnect(void*  _s, atransport*  t)
470{
471    asocket*  s    = _s;
472    asocket*  peer = s->peer;
473
474    D("remote_socket_disconnect RS(%d)\n", s->id);
475    if (peer) {
476        peer->peer = NULL;
477        peer->close(peer);
478    }
479    remove_transport_disconnect( s->transport, &((aremotesocket*)s)->disconnect );
480    free(s);
481}
482
483asocket *create_remote_socket(unsigned id, atransport *t)
484{
485    asocket *s = calloc(1, sizeof(aremotesocket));
486    adisconnect*  dis = &((aremotesocket*)s)->disconnect;
487
488    if (s == NULL) fatal("cannot allocate socket");
489    s->id = id;
490    s->enqueue = remote_socket_enqueue;
491    s->ready = remote_socket_ready;
492    s->close = remote_socket_close;
493    s->transport = t;
494
495    dis->func   = remote_socket_disconnect;
496    dis->opaque = s;
497    add_transport_disconnect( t, dis );
498    D("RS(%d): created\n", s->id);
499    return s;
500}
501
502void connect_to_remote(asocket *s, const char *destination)
503{
504    D("Connect_to_remote call \n");
505    apacket *p = get_apacket();
506    int len = strlen(destination) + 1;
507
508    if(len > (MAX_PAYLOAD-1)) {
509        fatal("destination oversized");
510    }
511
512    D("LS(%d): connect('%s')\n", s->id, destination);
513    p->msg.command = A_OPEN;
514    p->msg.arg0 = s->id;
515    p->msg.data_length = len;
516    strcpy((char*) p->data, destination);
517    send_packet(p, s->transport);
518}
519
520
521/* this is used by magic sockets to rig local sockets to
522   send the go-ahead message when they connect */
523static void local_socket_ready_notify(asocket *s)
524{
525    s->ready = local_socket_ready;
526    s->close = local_socket_close;
527    adb_write(s->fd, "OKAY", 4);
528    s->ready(s);
529}
530
531/* this is used by magic sockets to rig local sockets to
532   send the failure message if they are closed before
533   connected (to avoid closing them without a status message) */
534static void local_socket_close_notify(asocket *s)
535{
536    s->ready = local_socket_ready;
537    s->close = local_socket_close;
538    sendfailmsg(s->fd, "closed");
539    s->close(s);
540}
541
542unsigned unhex(unsigned char *s, int len)
543{
544    unsigned n = 0, c;
545
546    while(len-- > 0) {
547        switch((c = *s++)) {
548        case '0': case '1': case '2':
549        case '3': case '4': case '5':
550        case '6': case '7': case '8':
551        case '9':
552            c -= '0';
553            break;
554        case 'a': case 'b': case 'c':
555        case 'd': case 'e': case 'f':
556            c = c - 'a' + 10;
557            break;
558        case 'A': case 'B': case 'C':
559        case 'D': case 'E': case 'F':
560            c = c - 'A' + 10;
561            break;
562        default:
563            return 0xffffffff;
564        }
565
566        n = (n << 4) | c;
567    }
568
569    return n;
570}
571
572static int smart_socket_enqueue(asocket *s, apacket *p)
573{
574    unsigned len;
575#if ADB_HOST
576    char *service = NULL;
577    char* serial = NULL;
578    transport_type ttype = kTransportAny;
579#endif
580
581    D("SS(%d): enqueue %d\n", s->id, p->len);
582
583    if(s->pkt_first == 0) {
584        s->pkt_first = p;
585        s->pkt_last = p;
586    } else {
587        if((s->pkt_first->len + p->len) > MAX_PAYLOAD) {
588            D("SS(%d): overflow\n", s->id);
589            put_apacket(p);
590            goto fail;
591        }
592
593        memcpy(s->pkt_first->data + s->pkt_first->len,
594               p->data, p->len);
595        s->pkt_first->len += p->len;
596        put_apacket(p);
597
598        p = s->pkt_first;
599    }
600
601        /* don't bother if we can't decode the length */
602    if(p->len < 4) return 0;
603
604    len = unhex(p->data, 4);
605    if((len < 1) ||  (len > 1024)) {
606        D("SS(%d): bad size (%d)\n", s->id, len);
607        goto fail;
608    }
609
610    D("SS(%d): len is %d\n", s->id, len );
611        /* can't do anything until we have the full header */
612    if((len + 4) > p->len) {
613        D("SS(%d): waiting for %d more bytes\n", s->id, len+4 - p->len);
614        return 0;
615    }
616
617    p->data[len + 4] = 0;
618
619    D("SS(%d): '%s'\n", s->id, (char*) (p->data + 4));
620
621#if ADB_HOST
622    service = (char *)p->data + 4;
623    if(!strncmp(service, "host-serial:", strlen("host-serial:"))) {
624        char* serial_end;
625        service += strlen("host-serial:");
626
627        // serial number should follow "host:"
628        serial_end = strchr(service, ':');
629        if (serial_end) {
630            *serial_end = 0; // terminate string
631            serial = service;
632            service = serial_end + 1;
633        }
634    } else if (!strncmp(service, "host-usb:", strlen("host-usb:"))) {
635        ttype = kTransportUsb;
636        service += strlen("host-usb:");
637    } else if (!strncmp(service, "host-local:", strlen("host-local:"))) {
638        ttype = kTransportLocal;
639        service += strlen("host-local:");
640    } else if (!strncmp(service, "host:", strlen("host:"))) {
641        ttype = kTransportAny;
642        service += strlen("host:");
643    } else {
644        service = NULL;
645    }
646
647    if (service) {
648        asocket *s2;
649
650            /* some requests are handled immediately -- in that
651            ** case the handle_host_request() routine has sent
652            ** the OKAY or FAIL message and all we have to do
653            ** is clean up.
654            */
655        if(handle_host_request(service, ttype, serial, s->peer->fd, s) == 0) {
656                /* XXX fail message? */
657            D( "SS(%d): handled host service '%s'\n", s->id, service );
658            goto fail;
659        }
660        if (!strncmp(service, "transport", strlen("transport"))) {
661            D( "SS(%d): okay transport\n", s->id );
662            p->len = 0;
663            return 0;
664        }
665
666            /* try to find a local service with this name.
667            ** if no such service exists, we'll fail out
668            ** and tear down here.
669            */
670        s2 = create_host_service_socket(service, serial);
671        if(s2 == 0) {
672            D( "SS(%d): couldn't create host service '%s'\n", s->id, service );
673            sendfailmsg(s->peer->fd, "unknown host service");
674            goto fail;
675        }
676
677            /* we've connected to a local host service,
678            ** so we make our peer back into a regular
679            ** local socket and bind it to the new local
680            ** service socket, acknowledge the successful
681            ** connection, and close this smart socket now
682            ** that its work is done.
683            */
684        adb_write(s->peer->fd, "OKAY", 4);
685
686        s->peer->ready = local_socket_ready;
687        s->peer->close = local_socket_close;
688        s->peer->peer = s2;
689        s2->peer = s->peer;
690        s->peer = 0;
691        D( "SS(%d): okay\n", s->id );
692        s->close(s);
693
694            /* initial state is "ready" */
695        s2->ready(s2);
696        return 0;
697    }
698#else /* !ADB_HOST */
699    if (s->transport == NULL) {
700        char* error_string = "unknown failure";
701        s->transport = acquire_one_transport (CS_ANY,
702                kTransportAny, NULL, &error_string);
703
704        if (s->transport == NULL) {
705            sendfailmsg(s->peer->fd, error_string);
706            goto fail;
707        }
708    }
709#endif
710
711    if(!(s->transport) || (s->transport->connection_state == CS_OFFLINE)) {
712           /* if there's no remote we fail the connection
713            ** right here and terminate it
714            */
715        sendfailmsg(s->peer->fd, "device offline (x)");
716        goto fail;
717    }
718
719
720        /* instrument our peer to pass the success or fail
721        ** message back once it connects or closes, then
722        ** detach from it, request the connection, and
723        ** tear down
724        */
725    s->peer->ready = local_socket_ready_notify;
726    s->peer->close = local_socket_close_notify;
727    s->peer->peer = 0;
728        /* give him our transport and upref it */
729    s->peer->transport = s->transport;
730
731    connect_to_remote(s->peer, (char*) (p->data + 4));
732    s->peer = 0;
733    s->close(s);
734    return 1;
735
736fail:
737        /* we're going to close our peer as a side-effect, so
738        ** return -1 to signal that state to the local socket
739        ** who is enqueueing against us
740        */
741    s->close(s);
742    return -1;
743}
744
745static void smart_socket_ready(asocket *s)
746{
747    D("SS(%d): ready\n", s->id);
748}
749
750static void smart_socket_close(asocket *s)
751{
752    D("SS(%d): closed\n", s->id);
753    if(s->pkt_first){
754        put_apacket(s->pkt_first);
755    }
756    if(s->peer) {
757        s->peer->peer = 0;
758        s->peer->close(s->peer);
759    }
760    free(s);
761}
762
763asocket *create_smart_socket(void (*action_cb)(asocket *s, const char *act))
764{
765    D("Creating smart socket \n");
766    asocket *s = calloc(1, sizeof(asocket));
767    if (s == NULL) fatal("cannot allocate socket");
768    s->enqueue = smart_socket_enqueue;
769    s->ready = smart_socket_ready;
770    s->close = smart_socket_close;
771    s->extra = action_cb;
772
773    D("SS(%d): created %p\n", s->id, action_cb);
774    return s;
775}
776
777void smart_socket_action(asocket *s, const char *act)
778{
779
780}
781
782void connect_to_smartsocket(asocket *s)
783{
784    D("Connecting to smart socket \n");
785    asocket *ss = create_smart_socket(smart_socket_action);
786    s->peer = ss;
787    ss->peer = s;
788    s->ready(s);
789}
790