1 /*
2  *  TCP/IP or UDP/IP networking functions
3  *
4  *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
5  *  SPDX-License-Identifier: Apache-2.0
6  *
7  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
8  *  not use this file except in compliance with the License.
9  *  You may obtain a copy of the License at
10  *
11  *  http://www.apache.org/licenses/LICENSE-2.0
12  *
13  *  Unless required by applicable law or agreed to in writing, software
14  *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
15  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16  *  See the License for the specific language governing permissions and
17  *  limitations under the License.
18  *
19  *  This file is part of mbed TLS (https://tls.mbed.org)
20  */
21 
22 /* Enable definition of getaddrinfo() even when compiling with -std=c99. Must
23  * be set before config.h, which pulls in glibc's features.h indirectly.
24  * Harmless on other platforms. */
25 #define _POSIX_C_SOURCE 200112L
26 
27 #if !defined(MBEDTLS_CONFIG_FILE)
28 #include "mbedtls/config.h"
29 #else
30 #include MBEDTLS_CONFIG_FILE
31 #endif
32 
33 #if defined(MBEDTLS_NET_C)
34 
35 #if !defined(unix) && !defined(__unix__) && !defined(__unix) && \
36     !defined(__APPLE__) && !defined(_WIN32) && !defined(__QNXNTO__) && !defined(__CSKY__) && \
37     !defined(__HAIKU__)
38 #error "This module only works on Unix and Windows, see MBEDTLS_NET_C in config.h"
39 #endif
40 
41 #if defined(MBEDTLS_PLATFORM_C)
42 #include "mbedtls/platform.h"
43 #else
44 #include <stdlib.h>
45 #endif
46 
47 #include "mbedtls/net_sockets.h"
48 
49 #include <string.h>
50 
51 #if (defined(_WIN32) || defined(_WIN32_WCE)) && !defined(EFIX64) && \
52     !defined(EFI32)
53 
54 #define IS_EINTR( ret ) ( ( ret ) == WSAEINTR )
55 
56 #if !defined(_WIN32_WINNT) || (_WIN32_WINNT < 0x0501)
57 #undef _WIN32_WINNT
58 /* Enables getaddrinfo() & Co */
59 #define _WIN32_WINNT 0x0501
60 #endif
61 
62 #include <ws2tcpip.h>
63 
64 #include <winsock2.h>
65 #include <windows.h>
66 
67 #if defined(_MSC_VER)
68 #if defined(_WIN32_WCE)
69 #pragma comment( lib, "ws2.lib" )
70 #else
71 #pragma comment( lib, "ws2_32.lib" )
72 #endif
73 #endif /* _MSC_VER */
74 
75 #define read(fd,buf,len)        recv( fd, (char*)( buf ), (int)( len ), 0 )
76 #define write(fd,buf,len)       send( fd, (char*)( buf ), (int)( len ), 0 )
77 #define close(fd)               closesocket(fd)
78 
79 static int wsa_init_done = 0;
80 
81 #else /* ( _WIN32 || _WIN32_WCE ) && !EFIX64 && !EFI32 */
82 
83 #include <sys/types.h>
84 #include <sys/socket.h>
85 #include <netinet/in.h>
86 #include <arpa/inet.h>
87 #include <sys/time.h>
88 #include <unistd.h>
89 #include <signal.h>
90 #include <fcntl.h>
91 #include <netdb.h>
92 #include <errno.h>
93 
94 #define IS_EINTR( ret ) ( ( ret ) == EINTR )
95 
96 #endif /* ( _WIN32 || _WIN32_WCE ) && !EFIX64 && !EFI32 */
97 
98 /* Some MS functions want int and MSVC warns if we pass size_t,
99  * but the standard functions use socklen_t, so cast only for MSVC */
100 #if defined(_MSC_VER)
101 #define MSVC_INT_CAST   (int)
102 #else
103 #define MSVC_INT_CAST
104 #endif
105 
106 #include <stdio.h>
107 
108 #include <time.h>
109 
110 #include <stdint.h>
111 
112 /*
113  * Prepare for using the sockets interface
114  */
net_prepare(void)115 static int net_prepare( void )
116 {
117 #if ( defined(_WIN32) || defined(_WIN32_WCE) ) && !defined(EFIX64) && \
118     !defined(EFI32)
119     WSADATA wsaData;
120 
121     if( wsa_init_done == 0 )
122     {
123         if( WSAStartup( MAKEWORD(2,0), &wsaData ) != 0 )
124             return( MBEDTLS_ERR_NET_SOCKET_FAILED );
125 
126         wsa_init_done = 1;
127     }
128 #else
129 #if !defined(EFIX64) && !defined(EFI32) && !defined(__CSKY__)
130     signal( SIGPIPE, SIG_IGN );
131 #endif
132 #endif
133     return( 0 );
134 }
135 
136 /*
137  * Initialize a context
138  */
mbedtls_net_init(mbedtls_net_context * ctx)139 void mbedtls_net_init( mbedtls_net_context *ctx )
140 {
141     ctx->fd = -1;
142 }
143 
144 /*
145  * Initiate a TCP connection with host:port and the given protocol
146  */
mbedtls_net_connect(mbedtls_net_context * ctx,const char * host,const char * port,int proto)147 int mbedtls_net_connect( mbedtls_net_context *ctx, const char *host,
148                          const char *port, int proto )
149 {
150     int ret;
151     struct addrinfo hints, *addr_list, *cur;
152 
153     if( ( ret = net_prepare() ) != 0 )
154         return( ret );
155 
156     /* Do name resolution with both IPv6 and IPv4 */
157     memset( &hints, 0, sizeof( hints ) );
158     hints.ai_family = AF_UNSPEC;
159     hints.ai_socktype = proto == MBEDTLS_NET_PROTO_UDP ? SOCK_DGRAM : SOCK_STREAM;
160     hints.ai_protocol = proto == MBEDTLS_NET_PROTO_UDP ? IPPROTO_UDP : IPPROTO_TCP;
161 
162     if( getaddrinfo( host, port, &hints, &addr_list ) != 0 )
163         return( MBEDTLS_ERR_NET_UNKNOWN_HOST );
164 
165     /* Try the sockaddrs until a connection succeeds */
166     ret = MBEDTLS_ERR_NET_UNKNOWN_HOST;
167     for( cur = addr_list; cur != NULL; cur = cur->ai_next )
168     {
169         ctx->fd = (int) socket( cur->ai_family, cur->ai_socktype,
170                             cur->ai_protocol );
171         if( ctx->fd < 0 )
172         {
173             ret = MBEDTLS_ERR_NET_SOCKET_FAILED;
174             continue;
175         }
176 
177         if( connect( ctx->fd, cur->ai_addr, MSVC_INT_CAST cur->ai_addrlen ) == 0 )
178         {
179             ret = 0;
180             break;
181         }
182 
183         close( ctx->fd );
184         ret = MBEDTLS_ERR_NET_CONNECT_FAILED;
185     }
186 
187     freeaddrinfo( addr_list );
188 
189     return( ret );
190 }
191 
192 /*
193  * Create a listening socket on bind_ip:port
194  */
mbedtls_net_bind(mbedtls_net_context * ctx,const char * bind_ip,const char * port,int proto)195 int mbedtls_net_bind( mbedtls_net_context *ctx, const char *bind_ip, const char *port, int proto )
196 {
197     int n, ret;
198     struct addrinfo hints, *addr_list, *cur;
199 
200     if( ( ret = net_prepare() ) != 0 )
201         return( ret );
202 
203     /* Bind to IPv6 and/or IPv4, but only in the desired protocol */
204     memset( &hints, 0, sizeof( hints ) );
205     hints.ai_family = AF_UNSPEC;
206     hints.ai_socktype = proto == MBEDTLS_NET_PROTO_UDP ? SOCK_DGRAM : SOCK_STREAM;
207     hints.ai_protocol = proto == MBEDTLS_NET_PROTO_UDP ? IPPROTO_UDP : IPPROTO_TCP;
208     if( bind_ip == NULL )
209         hints.ai_flags = AI_PASSIVE;
210 
211     if( getaddrinfo( bind_ip, port, &hints, &addr_list ) != 0 )
212         return( MBEDTLS_ERR_NET_UNKNOWN_HOST );
213 
214     /* Try the sockaddrs until a binding succeeds */
215     ret = MBEDTLS_ERR_NET_UNKNOWN_HOST;
216     for( cur = addr_list; cur != NULL; cur = cur->ai_next )
217     {
218         ctx->fd = (int) socket( cur->ai_family, cur->ai_socktype,
219                             cur->ai_protocol );
220         if( ctx->fd < 0 )
221         {
222             ret = MBEDTLS_ERR_NET_SOCKET_FAILED;
223             continue;
224         }
225 
226         n = 1;
227         if( setsockopt( ctx->fd, SOL_SOCKET, SO_REUSEADDR,
228                         (const char *) &n, sizeof( n ) ) != 0 )
229         {
230             close( ctx->fd );
231             ret = MBEDTLS_ERR_NET_SOCKET_FAILED;
232             continue;
233         }
234 
235         if( bind( ctx->fd, cur->ai_addr, MSVC_INT_CAST cur->ai_addrlen ) != 0 )
236         {
237             close( ctx->fd );
238             ret = MBEDTLS_ERR_NET_BIND_FAILED;
239             continue;
240         }
241 
242         /* Listen only makes sense for TCP */
243         if( proto == MBEDTLS_NET_PROTO_TCP )
244         {
245             if( listen( ctx->fd, MBEDTLS_NET_LISTEN_BACKLOG ) != 0 )
246             {
247                 close( ctx->fd );
248                 ret = MBEDTLS_ERR_NET_LISTEN_FAILED;
249                 continue;
250             }
251         }
252 
253         /* Bind was successful */
254         ret = 0;
255         break;
256     }
257 
258     freeaddrinfo( addr_list );
259 
260     return( ret );
261 
262 }
263 
264 #if ( defined(_WIN32) || defined(_WIN32_WCE) ) && !defined(EFIX64) && \
265     !defined(EFI32)
266 /*
267  * Check if the requested operation would be blocking on a non-blocking socket
268  * and thus 'failed' with a negative return value.
269  */
net_would_block(const mbedtls_net_context * ctx)270 static int net_would_block( const mbedtls_net_context *ctx )
271 {
272     ((void) ctx);
273     return( WSAGetLastError() == WSAEWOULDBLOCK );
274 }
275 #else
276 /*
277  * Check if the requested operation would be blocking on a non-blocking socket
278  * and thus 'failed' with a negative return value.
279  *
280  * Note: on a blocking socket this function always returns 0!
281  */
net_would_block(const mbedtls_net_context * ctx)282 static int net_would_block( const mbedtls_net_context *ctx )
283 {
284     int err = errno;
285 
286     /*
287      * Never return 'WOULD BLOCK' on a non-blocking socket
288      */
289     if( ( fcntl( ctx->fd, F_GETFL ) & O_NONBLOCK ) != O_NONBLOCK )
290     {
291         errno = err;
292         return( 0 );
293     }
294 
295     switch( errno = err )
296     {
297 #if defined EAGAIN
298         case EAGAIN:
299 #endif
300 #if defined EWOULDBLOCK && EWOULDBLOCK != EAGAIN
301         case EWOULDBLOCK:
302 #endif
303             return( 1 );
304     }
305     return( 0 );
306 }
307 #endif /* ( _WIN32 || _WIN32_WCE ) && !EFIX64 && !EFI32 */
308 
309 /*
310  * Accept a connection from a remote client
311  */
mbedtls_net_accept(mbedtls_net_context * bind_ctx,mbedtls_net_context * client_ctx,void * client_ip,size_t buf_size,size_t * ip_len)312 int mbedtls_net_accept( mbedtls_net_context *bind_ctx,
313                         mbedtls_net_context *client_ctx,
314                         void *client_ip, size_t buf_size, size_t *ip_len )
315 {
316     int ret;
317     int type;
318 
319     struct sockaddr_storage client_addr;
320 
321 #if defined(__socklen_t_defined) || defined(_SOCKLEN_T) ||  \
322     defined(_SOCKLEN_T_DECLARED) || defined(__DEFINED_socklen_t)
323     socklen_t n = (socklen_t) sizeof( client_addr );
324     socklen_t type_len = (socklen_t) sizeof( type );
325 #else
326     int n = (int) sizeof( client_addr );
327     int type_len = (int) sizeof( type );
328 #endif
329 
330     /* Is this a TCP or UDP socket? */
331     if( getsockopt( bind_ctx->fd, SOL_SOCKET, SO_TYPE,
332                     (void *) &type, &type_len ) != 0 ||
333         ( type != SOCK_STREAM && type != SOCK_DGRAM ) )
334     {
335         return( MBEDTLS_ERR_NET_ACCEPT_FAILED );
336     }
337 
338     if( type == SOCK_STREAM )
339     {
340         /* TCP: actual accept() */
341         ret = client_ctx->fd = (int) accept( bind_ctx->fd,
342                                              (struct sockaddr *) &client_addr, &n );
343     }
344     else
345     {
346         /* UDP: wait for a message, but keep it in the queue */
347         char buf[1] = { 0 };
348 
349         ret = (int) recvfrom( bind_ctx->fd, buf, sizeof( buf ), MSG_PEEK,
350                         (struct sockaddr *) &client_addr, &n );
351 
352 #if defined(_WIN32)
353         if( ret == SOCKET_ERROR &&
354             WSAGetLastError() == WSAEMSGSIZE )
355         {
356             /* We know buf is too small, thanks, just peeking here */
357             ret = 0;
358         }
359 #endif
360     }
361 
362     if( ret < 0 )
363     {
364         if( net_would_block( bind_ctx ) != 0 )
365             return( MBEDTLS_ERR_SSL_WANT_READ );
366 
367         return( MBEDTLS_ERR_NET_ACCEPT_FAILED );
368     }
369 
370     /* UDP: hijack the listening socket to communicate with the client,
371      * then bind a new socket to accept new connections */
372     if( type != SOCK_STREAM )
373     {
374         struct sockaddr_storage local_addr;
375         int one = 1;
376 
377         if( connect( bind_ctx->fd, (struct sockaddr *) &client_addr, n ) != 0 )
378             return( MBEDTLS_ERR_NET_ACCEPT_FAILED );
379 
380         client_ctx->fd = bind_ctx->fd;
381         bind_ctx->fd   = -1; /* In case we exit early */
382 
383         n = sizeof( struct sockaddr_storage );
384         if( getsockname( client_ctx->fd,
385                          (struct sockaddr *) &local_addr, &n ) != 0 ||
386             ( bind_ctx->fd = (int) socket( local_addr.ss_family,
387                                            SOCK_DGRAM, IPPROTO_UDP ) ) < 0 ||
388             setsockopt( bind_ctx->fd, SOL_SOCKET, SO_REUSEADDR,
389                         (const char *) &one, sizeof( one ) ) != 0 )
390         {
391             return( MBEDTLS_ERR_NET_SOCKET_FAILED );
392         }
393 
394         if( bind( bind_ctx->fd, (struct sockaddr *) &local_addr, n ) != 0 )
395         {
396             return( MBEDTLS_ERR_NET_BIND_FAILED );
397         }
398     }
399 
400     if( client_ip != NULL )
401     {
402         if( client_addr.ss_family == AF_INET )
403         {
404             struct sockaddr_in *addr4 = (struct sockaddr_in *) &client_addr;
405             *ip_len = sizeof( addr4->sin_addr.s_addr );
406 
407             if( buf_size < *ip_len )
408                 return( MBEDTLS_ERR_NET_BUFFER_TOO_SMALL );
409 
410             memcpy( client_ip, &addr4->sin_addr.s_addr, *ip_len );
411         }
412         else
413         {
414             struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *) &client_addr;
415             *ip_len = sizeof( addr6->sin6_addr.s6_addr );
416 
417             if( buf_size < *ip_len )
418                 return( MBEDTLS_ERR_NET_BUFFER_TOO_SMALL );
419 
420             memcpy( client_ip, &addr6->sin6_addr.s6_addr, *ip_len);
421         }
422     }
423 
424     return( 0 );
425 }
426 
427 /*
428  * Set the socket blocking or non-blocking
429  */
mbedtls_net_set_block(mbedtls_net_context * ctx)430 int mbedtls_net_set_block( mbedtls_net_context *ctx )
431 {
432 #if ( defined(_WIN32) || defined(_WIN32_WCE) ) && !defined(EFIX64) && \
433     !defined(EFI32)
434     u_long n = 0;
435     return( ioctlsocket( ctx->fd, FIONBIO, &n ) );
436 #else
437     return( fcntl( ctx->fd, F_SETFL, fcntl( ctx->fd, F_GETFL ) & ~O_NONBLOCK ) );
438 #endif
439 }
440 
mbedtls_net_set_nonblock(mbedtls_net_context * ctx)441 int mbedtls_net_set_nonblock( mbedtls_net_context *ctx )
442 {
443 #if ( defined(_WIN32) || defined(_WIN32_WCE) ) && !defined(EFIX64) && \
444     !defined(EFI32)
445     u_long n = 1;
446     return( ioctlsocket( ctx->fd, FIONBIO, &n ) );
447 #else
448     return( fcntl( ctx->fd, F_SETFL, fcntl( ctx->fd, F_GETFL ) | O_NONBLOCK ) );
449 #endif
450 }
451 
452 /*
453  * Check if data is available on the socket
454  */
455 
mbedtls_net_poll(mbedtls_net_context * ctx,uint32_t rw,uint32_t timeout)456 int mbedtls_net_poll( mbedtls_net_context *ctx, uint32_t rw, uint32_t timeout )
457 {
458     int ret;
459     struct timeval tv;
460 
461     fd_set read_fds;
462     fd_set write_fds;
463 
464     int fd = ctx->fd;
465 
466     if( fd < 0 )
467         return( MBEDTLS_ERR_NET_INVALID_CONTEXT );
468 
469 #if defined(__has_feature)
470 #if __has_feature(memory_sanitizer)
471     /* Ensure that memory sanitizers consider read_fds and write_fds as
472      * initialized even on platforms such as Glibc/x86_64 where FD_ZERO
473      * is implemented in assembly. */
474     memset( &read_fds, 0, sizeof( read_fds ) );
475     memset( &write_fds, 0, sizeof( write_fds ) );
476 #endif
477 #endif
478 
479     FD_ZERO( &read_fds );
480     if( rw & MBEDTLS_NET_POLL_READ )
481     {
482         rw &= ~MBEDTLS_NET_POLL_READ;
483         FD_SET( fd, &read_fds );
484     }
485 
486     FD_ZERO( &write_fds );
487     if( rw & MBEDTLS_NET_POLL_WRITE )
488     {
489         rw &= ~MBEDTLS_NET_POLL_WRITE;
490         FD_SET( fd, &write_fds );
491     }
492 
493     if( rw != 0 )
494         return( MBEDTLS_ERR_NET_BAD_INPUT_DATA );
495 
496     tv.tv_sec  = timeout / 1000;
497     tv.tv_usec = ( timeout % 1000 ) * 1000;
498 
499     do
500     {
501         ret = select( fd + 1, &read_fds, &write_fds, NULL,
502                       timeout == (uint32_t) -1 ? NULL : &tv );
503     }
504     while( IS_EINTR( ret ) );
505 
506     if( ret < 0 )
507         return( MBEDTLS_ERR_NET_POLL_FAILED );
508 
509     ret = 0;
510     if( FD_ISSET( fd, &read_fds ) )
511         ret |= MBEDTLS_NET_POLL_READ;
512     if( FD_ISSET( fd, &write_fds ) )
513         ret |= MBEDTLS_NET_POLL_WRITE;
514 
515     return( ret );
516 }
517 
518 /*
519  * Portable usleep helper
520  */
mbedtls_net_usleep(unsigned long usec)521 void mbedtls_net_usleep( unsigned long usec )
522 {
523 #if defined(_WIN32)
524     Sleep( ( usec + 999 ) / 1000 );
525 #else
526     struct timeval tv;
527     tv.tv_sec  = usec / 1000000;
528 #if defined(__unix__) || defined(__unix) || \
529     ( defined(__APPLE__) && defined(__MACH__) )
530     tv.tv_usec = (suseconds_t) usec % 1000000;
531 #else
532     tv.tv_usec = usec % 1000000;
533 #endif
534     select( 0, NULL, NULL, NULL, &tv );
535 #endif
536 }
537 
538 /*
539  * Read at most 'len' characters
540  */
mbedtls_net_recv(void * ctx,unsigned char * buf,size_t len)541 int mbedtls_net_recv( void *ctx, unsigned char *buf, size_t len )
542 {
543     int ret;
544     int fd = ((mbedtls_net_context *) ctx)->fd;
545 
546     if( fd < 0 )
547         return( MBEDTLS_ERR_NET_INVALID_CONTEXT );
548 
549     ret = (int) read( fd, buf, len );
550 
551     if( ret < 0 )
552     {
553         if( net_would_block( ctx ) != 0 )
554             return( MBEDTLS_ERR_SSL_WANT_READ );
555 
556 #if ( defined(_WIN32) || defined(_WIN32_WCE) ) && !defined(EFIX64) && \
557     !defined(EFI32)
558         if( WSAGetLastError() == WSAECONNRESET )
559             return( MBEDTLS_ERR_NET_CONN_RESET );
560 #else
561         if( errno == EPIPE || errno == ECONNRESET )
562             return( MBEDTLS_ERR_NET_CONN_RESET );
563 
564         if( errno == EINTR )
565             return( MBEDTLS_ERR_SSL_WANT_READ );
566 #endif
567 
568         return( MBEDTLS_ERR_NET_RECV_FAILED );
569     }
570 
571     return( ret );
572 }
573 
574 /*
575  * Read at most 'len' characters, blocking for at most 'timeout' ms
576  */
mbedtls_net_recv_timeout(void * ctx,unsigned char * buf,size_t len,uint32_t timeout)577 int mbedtls_net_recv_timeout( void *ctx, unsigned char *buf,
578                               size_t len, uint32_t timeout )
579 {
580     int ret;
581     struct timeval tv;
582     fd_set read_fds;
583     int fd = ((mbedtls_net_context *) ctx)->fd;
584 
585     if( fd < 0 )
586         return( MBEDTLS_ERR_NET_INVALID_CONTEXT );
587 
588     FD_ZERO( &read_fds );
589     FD_SET( fd, &read_fds );
590 
591     tv.tv_sec  = timeout / 1000;
592     tv.tv_usec = ( timeout % 1000 ) * 1000;
593 
594     ret = select( fd + 1, &read_fds, NULL, NULL, timeout == 0 ? NULL : &tv );
595 
596     /* Zero fds ready means we timed out */
597     if( ret == 0 )
598         return( MBEDTLS_ERR_SSL_TIMEOUT );
599 
600     if( ret < 0 )
601     {
602 #if ( defined(_WIN32) || defined(_WIN32_WCE) ) && !defined(EFIX64) && \
603     !defined(EFI32)
604         if( WSAGetLastError() == WSAEINTR )
605             return( MBEDTLS_ERR_SSL_WANT_READ );
606 #else
607         if( errno == EINTR )
608             return( MBEDTLS_ERR_SSL_WANT_READ );
609 #endif
610 
611         return( MBEDTLS_ERR_NET_RECV_FAILED );
612     }
613 
614     /* This call will not block */
615     return( mbedtls_net_recv( ctx, buf, len ) );
616 }
617 
618 /*
619  * Write at most 'len' characters
620  */
mbedtls_net_send(void * ctx,const unsigned char * buf,size_t len)621 int mbedtls_net_send( void *ctx, const unsigned char *buf, size_t len )
622 {
623     int ret;
624     int fd = ((mbedtls_net_context *) ctx)->fd;
625 
626     if( fd < 0 )
627         return( MBEDTLS_ERR_NET_INVALID_CONTEXT );
628 
629     ret = (int) write( fd, buf, len );
630 
631     if( ret < 0 )
632     {
633         if( net_would_block( ctx ) != 0 )
634             return( MBEDTLS_ERR_SSL_WANT_WRITE );
635 
636 #if ( defined(_WIN32) || defined(_WIN32_WCE) ) && !defined(EFIX64) && \
637     !defined(EFI32)
638         if( WSAGetLastError() == WSAECONNRESET )
639             return( MBEDTLS_ERR_NET_CONN_RESET );
640 #else
641         if( errno == EPIPE || errno == ECONNRESET )
642             return( MBEDTLS_ERR_NET_CONN_RESET );
643 
644         if( errno == EINTR )
645             return( MBEDTLS_ERR_SSL_WANT_WRITE );
646 #endif
647 
648         return( MBEDTLS_ERR_NET_SEND_FAILED );
649     }
650 
651     return( ret );
652 }
653 
654 /*
655  * Gracefully close the connection
656  */
mbedtls_net_free(mbedtls_net_context * ctx)657 void mbedtls_net_free( mbedtls_net_context *ctx )
658 {
659     if( ctx->fd == -1 )
660         return;
661 
662     shutdown( ctx->fd, 2 );
663     close( ctx->fd );
664 
665     ctx->fd = -1;
666 }
667 
668 #endif /* MBEDTLS_NET_C */
669