mbedtls/library/net.c
Manuel Pégourié-Gonnard 0761733c1b Fix potential NULL dereference
We document that either of recv or recv_timeout may be NULL, but for TLS we
always used recv... Thanks Coverity for catching that.
(Not remotely trigerrable: local configuration.)

Also made me notice net_recv_timeout didn't do its job properly.
2015-06-25 10:59:57 +02:00

512 lines
13 KiB
C

/*
* TCP/IP or UDP/IP networking functions
*
* Copyright (C) 2006-2014, ARM Limited, All Rights Reserved
*
* This file is part of mbed TLS (https://tls.mbed.org)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#if !defined(MBEDTLS_CONFIG_FILE)
#include "mbedtls/config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif
#if defined(MBEDTLS_NET_C)
#include "mbedtls/net.h"
#include <string.h>
#if (defined(_WIN32) || defined(_WIN32_WCE)) && !defined(EFIX64) && \
!defined(EFI32)
#ifdef _WIN32_WINNT
#undef _WIN32_WINNT
#endif
/* Enables getaddrinfo() & Co */
#define _WIN32_WINNT 0x0501
#include <ws2tcpip.h>
#include <winsock2.h>
#include <windows.h>
#if defined(_MSC_VER)
#if defined(_WIN32_WCE)
#pragma comment( lib, "ws2.lib" )
#else
#pragma comment( lib, "ws2_32.lib" )
#endif
#endif /* _MSC_VER */
#define read(fd,buf,len) recv(fd,(char*)buf,(int) len,0)
#define write(fd,buf,len) send(fd,(char*)buf,(int) len,0)
#define close(fd) closesocket(fd)
static int wsa_init_done = 0;
#else /* ( _WIN32 || _WIN32_WCE ) && !EFIX64 && !EFI32 */
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/time.h>
#include <unistd.h>
#include <signal.h>
#include <fcntl.h>
#include <netdb.h>
#include <errno.h>
#endif /* ( _WIN32 || _WIN32_WCE ) && !EFIX64 && !EFI32 */
#include <stdlib.h>
#include <stdio.h>
#include <time.h>
#if defined(_MSC_VER) && !defined(EFIX64) && !defined(EFI32)
#include <basetsd.h>
typedef UINT32 uint32_t;
#else
#include <stdint.h>
#endif
/*
* Prepare for using the sockets interface
*/
static int net_prepare( void )
{
#if ( defined(_WIN32) || defined(_WIN32_WCE) ) && !defined(EFIX64) && \
!defined(EFI32)
WSADATA wsaData;
if( wsa_init_done == 0 )
{
if( WSAStartup( MAKEWORD(2,0), &wsaData ) != 0 )
return( MBEDTLS_ERR_NET_SOCKET_FAILED );
wsa_init_done = 1;
}
#else
#if !defined(EFIX64) && !defined(EFI32)
signal( SIGPIPE, SIG_IGN );
#endif
#endif
return( 0 );
}
/*
* Initiate a TCP connection with host:port and the given protocol
*/
int mbedtls_net_connect( int *fd, const char *host, const char *port, int proto )
{
int ret;
struct addrinfo hints, *addr_list, *cur;
if( ( ret = net_prepare() ) != 0 )
return( ret );
/* Do name resolution with both IPv6 and IPv4 */
memset( &hints, 0, sizeof( hints ) );
hints.ai_family = AF_UNSPEC;
hints.ai_socktype = proto == MBEDTLS_NET_PROTO_UDP ? SOCK_DGRAM : SOCK_STREAM;
hints.ai_protocol = proto == MBEDTLS_NET_PROTO_UDP ? IPPROTO_UDP : IPPROTO_TCP;
if( getaddrinfo( host, port, &hints, &addr_list ) != 0 )
return( MBEDTLS_ERR_NET_UNKNOWN_HOST );
/* Try the sockaddrs until a connection succeeds */
ret = MBEDTLS_ERR_NET_UNKNOWN_HOST;
for( cur = addr_list; cur != NULL; cur = cur->ai_next )
{
*fd = (int) socket( cur->ai_family, cur->ai_socktype,
cur->ai_protocol );
if( *fd < 0 )
{
ret = MBEDTLS_ERR_NET_SOCKET_FAILED;
continue;
}
if( connect( *fd, cur->ai_addr, cur->ai_addrlen ) == 0 )
{
ret = 0;
break;
}
close( *fd );
ret = MBEDTLS_ERR_NET_CONNECT_FAILED;
}
freeaddrinfo( addr_list );
return( ret );
}
/*
* Create a listening socket on bind_ip:port
*/
int mbedtls_net_bind( int *fd, const char *bind_ip, const char *port, int proto )
{
int n, ret;
struct addrinfo hints, *addr_list, *cur;
if( ( ret = net_prepare() ) != 0 )
return( ret );
/* Bind to IPv6 and/or IPv4, but only in TCP */
memset( &hints, 0, sizeof( hints ) );
hints.ai_family = AF_UNSPEC;
hints.ai_socktype = proto == MBEDTLS_NET_PROTO_UDP ? SOCK_DGRAM : SOCK_STREAM;
hints.ai_protocol = proto == MBEDTLS_NET_PROTO_UDP ? IPPROTO_UDP : IPPROTO_TCP;
if( bind_ip == NULL )
hints.ai_flags = AI_PASSIVE;
if( getaddrinfo( bind_ip, port, &hints, &addr_list ) != 0 )
return( MBEDTLS_ERR_NET_UNKNOWN_HOST );
/* Try the sockaddrs until a binding succeeds */
ret = MBEDTLS_ERR_NET_UNKNOWN_HOST;
for( cur = addr_list; cur != NULL; cur = cur->ai_next )
{
*fd = (int) socket( cur->ai_family, cur->ai_socktype,
cur->ai_protocol );
if( *fd < 0 )
{
ret = MBEDTLS_ERR_NET_SOCKET_FAILED;
continue;
}
n = 1;
if( setsockopt( *fd, SOL_SOCKET, SO_REUSEADDR,
(const char *) &n, sizeof( n ) ) != 0 )
{
close( *fd );
ret = MBEDTLS_ERR_NET_SOCKET_FAILED;
continue;
}
if( bind( *fd, cur->ai_addr, cur->ai_addrlen ) != 0 )
{
close( *fd );
ret = MBEDTLS_ERR_NET_BIND_FAILED;
continue;
}
/* Listen only makes sense for TCP */
if( proto == MBEDTLS_NET_PROTO_TCP )
{
if( listen( *fd, MBEDTLS_NET_LISTEN_BACKLOG ) != 0 )
{
close( *fd );
ret = MBEDTLS_ERR_NET_LISTEN_FAILED;
continue;
}
}
/* I we ever get there, it's a success */
ret = 0;
break;
}
freeaddrinfo( addr_list );
return( ret );
}
#if ( defined(_WIN32) || defined(_WIN32_WCE) ) && !defined(EFIX64) && \
!defined(EFI32)
/*
* Check if the requested operation would be blocking on a non-blocking socket
* and thus 'failed' with a negative return value.
*/
static int net_would_block( int fd )
{
((void) fd);
return( WSAGetLastError() == WSAEWOULDBLOCK );
}
#else
/*
* Check if the requested operation would be blocking on a non-blocking socket
* and thus 'failed' with a negative return value.
*
* Note: on a blocking socket this function always returns 0!
*/
static int net_would_block( int fd )
{
/*
* Never return 'WOULD BLOCK' on a non-blocking socket
*/
if( ( fcntl( fd, F_GETFL ) & O_NONBLOCK ) != O_NONBLOCK )
return( 0 );
switch( errno )
{
#if defined EAGAIN
case EAGAIN:
#endif
#if defined EWOULDBLOCK && EWOULDBLOCK != EAGAIN
case EWOULDBLOCK:
#endif
return( 1 );
}
return( 0 );
}
#endif /* ( _WIN32 || _WIN32_WCE ) && !EFIX64 && !EFI32 */
/*
* Accept a connection from a remote client
*/
int mbedtls_net_accept( int bind_fd, int *client_fd,
void *client_ip, size_t buf_size, size_t *ip_len )
{
int ret;
int type;
struct sockaddr_storage client_addr;
#if defined(__socklen_t_defined) || defined(_SOCKLEN_T) || \
defined(_SOCKLEN_T_DECLARED)
socklen_t n = (socklen_t) sizeof( client_addr );
socklen_t type_len = (socklen_t) sizeof( type );
#else
int n = (int) sizeof( client_addr );
int type_len = (int) sizeof( type );
#endif
/* Is this a TCP or UDP socket? */
if( getsockopt( bind_fd, SOL_SOCKET, SO_TYPE, (void *) &type, &type_len ) != 0 ||
( type != SOCK_STREAM && type != SOCK_DGRAM ) )
{
return( MBEDTLS_ERR_NET_ACCEPT_FAILED );
}
if( type == SOCK_STREAM )
{
/* TCP: actual accept() */
ret = *client_fd = (int) accept( bind_fd,
(struct sockaddr *) &client_addr, &n );
}
else
{
/* UDP: wait for a message, but keep it in the queue */
char buf[1] = { 0 };
ret = recvfrom( bind_fd, buf, sizeof( buf ), MSG_PEEK,
(struct sockaddr *) &client_addr, &n );
}
if( ret < 0 )
{
if( net_would_block( bind_fd ) != 0 )
return( MBEDTLS_ERR_SSL_WANT_READ );
return( MBEDTLS_ERR_NET_ACCEPT_FAILED );
}
/* UDP: hijack the listening socket for communicating with the client */
if( type != SOCK_STREAM )
{
if( connect( bind_fd, (struct sockaddr *) &client_addr, n ) != 0 )
return( MBEDTLS_ERR_NET_ACCEPT_FAILED );
*client_fd = bind_fd;
}
if( client_ip != NULL )
{
if( client_addr.ss_family == AF_INET )
{
struct sockaddr_in *addr4 = (struct sockaddr_in *) &client_addr;
*ip_len = sizeof( addr4->sin_addr.s_addr );
if( buf_size < *ip_len )
return( MBEDTLS_ERR_NET_BUFFER_TOO_SMALL );
memcpy( client_ip, &addr4->sin_addr.s_addr, *ip_len );
}
else
{
struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *) &client_addr;
*ip_len = sizeof( addr6->sin6_addr.s6_addr );
if( buf_size < *ip_len )
return( MBEDTLS_ERR_NET_BUFFER_TOO_SMALL );
memcpy( client_ip, &addr6->sin6_addr.s6_addr, *ip_len);
}
}
return( 0 );
}
/*
* Set the socket blocking or non-blocking
*/
int mbedtls_net_set_block( int fd )
{
#if ( defined(_WIN32) || defined(_WIN32_WCE) ) && !defined(EFIX64) && \
!defined(EFI32)
u_long n = 0;
return( ioctlsocket( fd, FIONBIO, &n ) );
#else
return( fcntl( fd, F_SETFL, fcntl( fd, F_GETFL ) & ~O_NONBLOCK ) );
#endif
}
int mbedtls_net_set_nonblock( int fd )
{
#if ( defined(_WIN32) || defined(_WIN32_WCE) ) && !defined(EFIX64) && \
!defined(EFI32)
u_long n = 1;
return( ioctlsocket( fd, FIONBIO, &n ) );
#else
return( fcntl( fd, F_SETFL, fcntl( fd, F_GETFL ) | O_NONBLOCK ) );
#endif
}
/*
* Portable usleep helper
*/
void mbedtls_net_usleep( unsigned long usec )
{
struct timeval tv;
tv.tv_sec = usec / 1000000;
#if !defined(_WIN32) && ( defined(__unix__) || defined(__unix) || \
( defined(__APPLE__) && defined(__MACH__) ) )
tv.tv_usec = (suseconds_t) usec % 1000000;
#else
tv.tv_usec = usec % 1000000;
#endif
select( 0, NULL, NULL, NULL, &tv );
}
/*
* Read at most 'len' characters
*/
int mbedtls_net_recv( void *ctx, unsigned char *buf, size_t len )
{
int fd = *((int *) ctx);
int ret = (int) read( fd, buf, len );
if( ret < 0 )
{
if( net_would_block( fd ) != 0 )
return( MBEDTLS_ERR_SSL_WANT_READ );
#if ( defined(_WIN32) || defined(_WIN32_WCE) ) && !defined(EFIX64) && \
!defined(EFI32)
if( WSAGetLastError() == WSAECONNRESET )
return( MBEDTLS_ERR_NET_CONN_RESET );
#else
if( errno == EPIPE || errno == ECONNRESET )
return( MBEDTLS_ERR_NET_CONN_RESET );
if( errno == EINTR )
return( MBEDTLS_ERR_SSL_WANT_READ );
#endif
return( MBEDTLS_ERR_NET_RECV_FAILED );
}
return( ret );
}
/*
* Read at most 'len' characters, blocking for at most 'timeout' ms
*/
int mbedtls_net_recv_timeout( void *ctx, unsigned char *buf, size_t len,
uint32_t timeout )
{
int ret;
struct timeval tv;
fd_set read_fds;
int fd = *((int *) ctx);
FD_ZERO( &read_fds );
FD_SET( fd, &read_fds );
tv.tv_sec = timeout / 1000;
tv.tv_usec = ( timeout % 1000 ) * 1000;
ret = select( fd + 1, &read_fds, NULL, NULL, timeout == 0 ? NULL : &tv );
/* Zero fds ready means we timed out */
if( ret == 0 )
return( MBEDTLS_ERR_SSL_TIMEOUT );
if( ret < 0 )
{
#if ( defined(_WIN32) || defined(_WIN32_WCE) ) && !defined(EFIX64) && \
!defined(EFI32)
if( WSAGetLastError() == WSAEINTR )
return( MBEDTLS_ERR_SSL_WANT_READ );
#else
if( errno == EINTR )
return( MBEDTLS_ERR_SSL_WANT_READ );
#endif
return( MBEDTLS_ERR_NET_RECV_FAILED );
}
/* This call will not block */
return( mbedtls_net_recv( ctx, buf, len ) );
}
/*
* Write at most 'len' characters
*/
int mbedtls_net_send( void *ctx, const unsigned char *buf, size_t len )
{
int fd = *((int *) ctx);
int ret = (int) write( fd, buf, len );
if( ret < 0 )
{
if( net_would_block( fd ) != 0 )
return( MBEDTLS_ERR_SSL_WANT_WRITE );
#if ( defined(_WIN32) || defined(_WIN32_WCE) ) && !defined(EFIX64) && \
!defined(EFI32)
if( WSAGetLastError() == WSAECONNRESET )
return( MBEDTLS_ERR_NET_CONN_RESET );
#else
if( errno == EPIPE || errno == ECONNRESET )
return( MBEDTLS_ERR_NET_CONN_RESET );
if( errno == EINTR )
return( MBEDTLS_ERR_SSL_WANT_WRITE );
#endif
return( MBEDTLS_ERR_NET_SEND_FAILED );
}
return( ret );
}
/*
* Gracefully close the connection
*/
void mbedtls_net_close( int fd )
{
shutdown( fd, 2 );
close( fd );
}
#endif /* MBEDTLS_NET_C */