summaryrefslogblamecommitdiffstats
path: root/minadbd/sockets.c
blob: 2dd646159d85b40a027681b0cdf2eb968fd36740 (plain) (tree)
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
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415






























































































































































































































































































































































































































                                                                                                                  






















































































































































































                                                                                  








































                                                                        









                                                     
















































































                                                                            
/*
 * Copyright (C) 2007 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <ctype.h>

#include "sysdeps.h"

#define  TRACE_TAG  TRACE_SOCKETS
#include "adb.h"

ADB_MUTEX_DEFINE( socket_list_lock );

static void local_socket_close_locked(asocket *s);

int sendfailmsg(int fd, const char *reason)
{
    char buf[9];
    int len;
    len = strlen(reason);
    if(len > 0xffff) len = 0xffff;
    snprintf(buf, sizeof buf, "FAIL%04x", len);
    if(writex(fd, buf, 8)) return -1;
    return writex(fd, reason, len);
}

//extern int online;

static unsigned local_socket_next_id = 1;

static asocket local_socket_list = {
    .next = &local_socket_list,
    .prev = &local_socket_list,
};

/* the the list of currently closing local sockets.
** these have no peer anymore, but still packets to
** write to their fd.
*/
static asocket local_socket_closing_list = {
    .next = &local_socket_closing_list,
    .prev = &local_socket_closing_list,
};

asocket *find_local_socket(unsigned id)
{
    asocket *s;
    asocket *result = NULL;

    adb_mutex_lock(&socket_list_lock);
    for (s = local_socket_list.next; s != &local_socket_list; s = s->next) {
        if (s->id == id) {
            result = s;
            break;
        }
    }
    adb_mutex_unlock(&socket_list_lock);

    return result;
}

static void
insert_local_socket(asocket*  s, asocket*  list)
{
    s->next       = list;
    s->prev       = s->next->prev;
    s->prev->next = s;
    s->next->prev = s;
}


void install_local_socket(asocket *s)
{
    adb_mutex_lock(&socket_list_lock);

    s->id = local_socket_next_id++;
    insert_local_socket(s, &local_socket_list);

    adb_mutex_unlock(&socket_list_lock);
}

void remove_socket(asocket *s)
{
    // socket_list_lock should already be held
    if (s->prev && s->next)
    {
        s->prev->next = s->next;
        s->next->prev = s->prev;
        s->next = 0;
        s->prev = 0;
        s->id = 0;
    }
}

void close_all_sockets(atransport *t)
{
    asocket *s;

        /* this is a little gross, but since s->close() *will* modify
        ** the list out from under you, your options are limited.
        */
    adb_mutex_lock(&socket_list_lock);
restart:
    for(s = local_socket_list.next; s != &local_socket_list; s = s->next){
        if(s->transport == t || (s->peer && s->peer->transport == t)) {
            local_socket_close_locked(s);
            goto restart;
        }
    }
    adb_mutex_unlock(&socket_list_lock);
}

static int local_socket_enqueue(asocket *s, apacket *p)
{
    D("LS(%d): enqueue %d\n", s->id, p->len);

    p->ptr = p->data;

        /* if there is already data queue'd, we will receive
        ** events when it's time to write.  just add this to
        ** the tail
        */
    if(s->pkt_first) {
        goto enqueue;
    }

        /* write as much as we can, until we
        ** would block or there is an error/eof
        */
    while(p->len > 0) {
        int r = adb_write(s->fd, p->ptr, p->len);
        if(r > 0) {
            p->len -= r;
            p->ptr += r;
            continue;
        }
        if((r == 0) || (errno != EAGAIN)) {
            D( "LS(%d): not ready, errno=%d: %s\n", s->id, errno, strerror(errno) );
            s->close(s);
            return 1; /* not ready (error) */
        } else {
            break;
        }
    }

    if(p->len == 0) {
        put_apacket(p);
        return 0; /* ready for more data */
    }

enqueue:
    p->next = 0;
    if(s->pkt_first) {
        s->pkt_last->next = p;
    } else {
        s->pkt_first = p;
    }
    s->pkt_last = p;

        /* make sure we are notified when we can drain the queue */
    fdevent_add(&s->fde, FDE_WRITE);

    return 1; /* not ready (backlog) */
}

static void local_socket_ready(asocket *s)
{
        /* far side is ready for data, pay attention to
           readable events */
    fdevent_add(&s->fde, FDE_READ);
//    D("LS(%d): ready()\n", s->id);
}

static void local_socket_close(asocket *s)
{
    adb_mutex_lock(&socket_list_lock);
    local_socket_close_locked(s);
    adb_mutex_unlock(&socket_list_lock);
}

// be sure to hold the socket list lock when calling this
static void local_socket_destroy(asocket  *s)
{
    apacket *p, *n;
    D("LS(%d): destroying fde.fd=%d\n", s->id, s->fde.fd);

        /* IMPORTANT: the remove closes the fd
        ** that belongs to this socket
        */
    fdevent_remove(&s->fde);

        /* dispose of any unwritten data */
    for(p = s->pkt_first; p; p = n) {
        D("LS(%d): discarding %d bytes\n", s->id, p->len);
        n = p->next;
        put_apacket(p);
    }
    remove_socket(s);
    free(s);
}


static void local_socket_close_locked(asocket *s)
{
    D("entered. LS(%d) fd=%d\n", s->id, s->fd);
    if(s->peer) {
        D("LS(%d): closing peer. peer->id=%d peer->fd=%d\n",
          s->id, s->peer->id, s->peer->fd);
        s->peer->peer = 0;
        // tweak to avoid deadlock
        if (s->peer->close == local_socket_close) {
            local_socket_close_locked(s->peer);
        } else {
            s->peer->close(s->peer);
        }
        s->peer = 0;
    }

        /* If we are already closing, or if there are no
        ** pending packets, destroy immediately
        */
    if (s->closing || s->pkt_first == NULL) {
        int   id = s->id;
        local_socket_destroy(s);
        D("LS(%d): closed\n", id);
        return;
    }

        /* otherwise, put on the closing list
        */
    D("LS(%d): closing\n", s->id);
    s->closing = 1;
    fdevent_del(&s->fde, FDE_READ);
    remove_socket(s);
    D("LS(%d): put on socket_closing_list fd=%d\n", s->id, s->fd);
    insert_local_socket(s, &local_socket_closing_list);
}

static void local_socket_event_func(int fd, unsigned ev, void *_s)
{
    asocket *s = _s;

    D("LS(%d): event_func(fd=%d(==%d), ev=%04x)\n", s->id, s->fd, fd, ev);

    /* put the FDE_WRITE processing before the FDE_READ
    ** in order to simplify the code.
    */
    if(ev & FDE_WRITE){
        apacket *p;

        while((p = s->pkt_first) != 0) {
            while(p->len > 0) {
                int r = adb_write(fd, p->ptr, p->len);
                if(r > 0) {
                    p->ptr += r;
                    p->len -= r;
                    continue;
                }
                if(r < 0) {
                    /* returning here is ok because FDE_READ will
                    ** be processed in the next iteration loop
                    */
                    if(errno == EAGAIN) return;
                    if(errno == EINTR) continue;
                }
                D(" closing after write because r=%d and errno is %d\n", r, errno);
                s->close(s);
                return;
            }

            if(p->len == 0) {
                s->pkt_first = p->next;
                if(s->pkt_first == 0) s->pkt_last = 0;
                put_apacket(p);
            }
        }

            /* if we sent the last packet of a closing socket,
            ** we can now destroy it.
            */
        if (s->closing) {
            D(" closing because 'closing' is set after write\n");
            s->close(s);
            return;
        }

            /* no more packets queued, so we can ignore
            ** writable events again and tell our peer
            ** to resume writing
            */
        fdevent_del(&s->fde, FDE_WRITE);
        s->peer->ready(s->peer);
    }


    if(ev & FDE_READ){
        apacket *p = get_apacket();
        unsigned char *x = p->data;
        size_t avail = MAX_PAYLOAD;
        int r;
        int is_eof = 0;

        while(avail > 0) {
            r = adb_read(fd, x, avail);
            D("LS(%d): post adb_read(fd=%d,...) r=%d (errno=%d) avail=%d\n", s->id, s->fd, r, r<0?errno:0, avail);
            if(r > 0) {
                avail -= r;
                x += r;
                continue;
            }
            if(r < 0) {
                if(errno == EAGAIN) break;
                if(errno == EINTR) continue;
            }

                /* r = 0 or unhandled error */
            is_eof = 1;
            break;
        }
        D("LS(%d): fd=%d post avail loop. r=%d is_eof=%d forced_eof=%d\n",
          s->id, s->fd, r, is_eof, s->fde.force_eof);
        if((avail == MAX_PAYLOAD) || (s->peer == 0)) {
            put_apacket(p);
        } else {
            p->len = MAX_PAYLOAD - avail;

            r = s->peer->enqueue(s->peer, p);
            D("LS(%d): fd=%d post peer->enqueue(). r=%d\n", s->id, s->fd, r);

            if(r < 0) {
                    /* error return means they closed us as a side-effect
                    ** and we must return immediately.
                    **
                    ** note that if we still have buffered packets, the
                    ** socket will be placed on the closing socket list.
                    ** this handler function will be called again
                    ** to process FDE_WRITE events.
                    */
                return;
            }

            if(r > 0) {
                    /* if the remote cannot accept further events,
                    ** we disable notification of READs.  They'll
                    ** be enabled again when we get a call to ready()
                    */
                fdevent_del(&s->fde, FDE_READ);
            }
        }
        /* Don't allow a forced eof if data is still there */
        if((s->fde.force_eof && !r) || is_eof) {
            D(" closing because is_eof=%d r=%d s->fde.force_eof=%d\n", is_eof, r, s->fde.force_eof);
            s->close(s);
        }
    }

    if(ev & FDE_ERROR){
            /* this should be caught be the next read or write
            ** catching it here means we may skip the last few
            ** bytes of readable data.
            */
//        s->close(s);
        D("LS(%d): FDE_ERROR (fd=%d)\n", s->id, s->fd);

        return;
    }
}

asocket *create_local_socket(int fd)
{
    asocket *s = calloc(1, sizeof(asocket));
    if (s == NULL) fatal("cannot allocate socket");
    s->fd = fd;
    s->enqueue = local_socket_enqueue;
    s->ready = local_socket_ready;
    s->close = local_socket_close;
    install_local_socket(s);

    fdevent_install(&s->fde, fd, local_socket_event_func, s);
/*    fdevent_add(&s->fde, FDE_ERROR); */
    //fprintf(stderr, "Created local socket in create_local_socket \n");
    D("LS(%d): created (fd=%d)\n", s->id, s->fd);
    return s;
}

asocket *create_local_service_socket(const char *name)
{
    asocket *s;
    int fd;

    fd = service_to_fd(name);
    if(fd < 0) return 0;

    s = create_local_socket(fd);
    D("LS(%d): bound to '%s' via %d\n", s->id, name, fd);
    return s;
}

/* a Remote socket is used to send/receive data to/from a given transport object
** it needs to be closed when the transport is forcibly destroyed by the user
*/
typedef struct aremotesocket {
    asocket      socket;
    adisconnect  disconnect;
} aremotesocket;

static int remote_socket_enqueue(asocket *s, apacket *p)
{
    D("entered remote_socket_enqueue RS(%d) WRITE fd=%d peer.fd=%d\n",
      s->id, s->fd, s->peer->fd);
    p->msg.command = A_WRTE;
    p->msg.arg0 = s->peer->id;
    p->msg.arg1 = s->id;
    p->msg.data_length = p->len;
    send_packet(p, s->transport);
    return 1;
}

static void remote_socket_ready(asocket *s)
{
    D("entered remote_socket_ready RS(%d) OKAY fd=%d peer.fd=%d\n",
      s->id, s->fd, s->peer->fd);
    apacket *p = get_apacket();
    p->msg.command = A_OKAY;
    p->msg.arg0 = s->peer->id;
    p->msg.arg1 = s->id;
    send_packet(p, s->transport);
}

static void remote_socket_close(asocket *s)
{
    D("entered remote_socket_close RS(%d) CLOSE fd=%d peer->fd=%d\n",
      s->id, s->fd, s->peer?s->peer->fd:-1);
    apacket *p = get_apacket();
    p->msg.command = A_CLSE;
    if(s->peer) {
        p->msg.arg0 = s->peer->id;
        s->peer->peer = 0;
        D("RS(%d) peer->close()ing peer->id=%d peer->fd=%d\n",
          s->id, s->peer->id, s->peer->fd);
        s->peer->close(s->peer);
    }
    p->msg.arg1 = s->id;
    send_packet(p, s->transport);
    D("RS(%d): closed\n", s->id);
    remove_transport_disconnect( s->transport, &((aremotesocket*)s)->disconnect );
    free(s);
}

static void remote_socket_disconnect(void*  _s, atransport*  t)
{
    asocket*  s    = _s;
    asocket*  peer = s->peer;

    D("remote_socket_disconnect RS(%d)\n", s->id);
    if (peer) {
        peer->peer = NULL;
        peer->close(peer);
    }
    remove_transport_disconnect( s->transport, &((aremotesocket*)s)->disconnect );
    free(s);
}

asocket *create_remote_socket(unsigned id, atransport *t)
{
    asocket *s = calloc(1, sizeof(aremotesocket));
    adisconnect*  dis = &((aremotesocket*)s)->disconnect;

    if (s == NULL) fatal("cannot allocate socket");
    s->id = id;
    s->enqueue = remote_socket_enqueue;
    s->ready = remote_socket_ready;
    s->close = remote_socket_close;
    s->transport = t;

    dis->func   = remote_socket_disconnect;
    dis->opaque = s;
    add_transport_disconnect( t, dis );
    D("RS(%d): created\n", s->id);
    return s;
}

void connect_to_remote(asocket *s, const char *destination)
{
    D("Connect_to_remote call RS(%d) fd=%d\n", s->id, s->fd);
    apacket *p = get_apacket();
    int len = strlen(destination) + 1;

    if(len > (MAX_PAYLOAD-1)) {
        fatal("destination oversized");
    }

    D("LS(%d): connect('%s')\n", s->id, destination);
    p->msg.command = A_OPEN;
    p->msg.arg0 = s->id;
    p->msg.data_length = len;
    strcpy((char*) p->data, destination);
    send_packet(p, s->transport);
}


/* this is used by magic sockets to rig local sockets to
   send the go-ahead message when they connect */
static void local_socket_ready_notify(asocket *s)
{
    s->ready = local_socket_ready;
    s->close = local_socket_close;
    adb_write(s->fd, "OKAY", 4);
    s->ready(s);
}

/* this is used by magic sockets to rig local sockets to
   send the failure message if they are closed before
   connected (to avoid closing them without a status message) */
static void local_socket_close_notify(asocket *s)
{
    s->ready = local_socket_ready;
    s->close = local_socket_close;
    sendfailmsg(s->fd, "closed");
    s->close(s);
}

unsigned unhex(unsigned char *s, int len)
{
    unsigned n = 0, c;

    while(len-- > 0) {
        switch((c = *s++)) {
        case '0': case '1': case '2':
        case '3': case '4': case '5':
        case '6': case '7': case '8':
        case '9':
            c -= '0';
            break;
        case 'a': case 'b': case 'c':
        case 'd': case 'e': case 'f':
            c = c - 'a' + 10;
            break;
        case 'A': case 'B': case 'C':
        case 'D': case 'E': case 'F':
            c = c - 'A' + 10;
            break;
        default:
            return 0xffffffff;
        }

        n = (n << 4) | c;
    }

    return n;
}

/* skip_host_serial return the position in a string
   skipping over the 'serial' parameter in the ADB protocol,
   where parameter string may be a host:port string containing
   the protocol delimiter (colon). */
char *skip_host_serial(char *service) {
    char *first_colon, *serial_end;

    first_colon = strchr(service, ':');
    if (!first_colon) {
        /* No colon in service string. */
        return NULL;
    }
    serial_end = first_colon;
    if (isdigit(serial_end[1])) {
        serial_end++;
        while ((*serial_end) && isdigit(*serial_end)) {
            serial_end++;
        }
        if ((*serial_end) != ':') {
            // Something other than numbers was found, reset the end.
            serial_end = first_colon;
        }
    }
    return serial_end;
}

static int smart_socket_enqueue(asocket *s, apacket *p)
{
    unsigned len;

    D("SS(%d): enqueue %d\n", s->id, p->len);

    if(s->pkt_first == 0) {
        s->pkt_first = p;
        s->pkt_last = p;
    } else {
        if((s->pkt_first->len + p->len) > MAX_PAYLOAD) {
            D("SS(%d): overflow\n", s->id);
            put_apacket(p);
            goto fail;
        }

        memcpy(s->pkt_first->data + s->pkt_first->len,
               p->data, p->len);
        s->pkt_first->len += p->len;
        put_apacket(p);

        p = s->pkt_first;
    }

        /* don't bother if we can't decode the length */
    if(p->len < 4) return 0;

    len = unhex(p->data, 4);
    if((len < 1) ||  (len > 1024)) {
        D("SS(%d): bad size (%d)\n", s->id, len);
        goto fail;
    }

    D("SS(%d): len is %d\n", s->id, len );
        /* can't do anything until we have the full header */
    if((len + 4) > p->len) {
        D("SS(%d): waiting for %d more bytes\n", s->id, len+4 - p->len);
        return 0;
    }

    p->data[len + 4] = 0;

    D("SS(%d): '%s'\n", s->id, (char*) (p->data + 4));

    if (s->transport == NULL) {
        char* error_string = "unknown failure";
        s->transport = acquire_one_transport (CS_ANY,
                kTransportAny, NULL, &error_string);

        if (s->transport == NULL) {
            sendfailmsg(s->peer->fd, error_string);
            goto fail;
        }
    }

    if(!(s->transport) || (s->transport->connection_state == CS_OFFLINE)) {
           /* if there's no remote we fail the connection
            ** right here and terminate it
            */
        sendfailmsg(s->peer->fd, "device offline (x)");
        goto fail;
    }


        /* instrument our peer to pass the success or fail
        ** message back once it connects or closes, then
        ** detach from it, request the connection, and
        ** tear down
        */
    s->peer->ready = local_socket_ready_notify;
    s->peer->close = local_socket_close_notify;
    s->peer->peer = 0;
        /* give him our transport and upref it */
    s->peer->transport = s->transport;

    connect_to_remote(s->peer, (char*) (p->data + 4));
    s->peer = 0;
    s->close(s);
    return 1;

fail:
        /* we're going to close our peer as a side-effect, so
        ** return -1 to signal that state to the local socket
        ** who is enqueueing against us
        */
    s->close(s);
    return -1;
}

static void smart_socket_ready(asocket *s)
{
    D("SS(%d): ready\n", s->id);
}

static void smart_socket_close(asocket *s)
{
    D("SS(%d): closed\n", s->id);
    if(s->pkt_first){
        put_apacket(s->pkt_first);
    }
    if(s->peer) {
        s->peer->peer = 0;
        s->peer->close(s->peer);
        s->peer = 0;
    }
    free(s);
}

asocket *create_smart_socket(void (*action_cb)(asocket *s, const char *act))
{
    D("Creating smart socket \n");
    asocket *s = calloc(1, sizeof(asocket));
    if (s == NULL) fatal("cannot allocate socket");
    s->enqueue = smart_socket_enqueue;
    s->ready = smart_socket_ready;
    s->close = smart_socket_close;
    s->extra = action_cb;

    D("SS(%d): created %p\n", s->id, action_cb);
    return s;
}

void smart_socket_action(asocket *s, const char *act)
{

}

void connect_to_smartsocket(asocket *s)
{
    D("Connecting to smart socket \n");
    asocket *ss = create_smart_socket(smart_socket_action);
    s->peer = ss;
    ss->peer = s;
    s->ready(s);
}