tor-browser

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pripv6.c (11674B)


      1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
      2 /* This Source Code Form is subject to the terms of the Mozilla Public
      3 * License, v. 2.0. If a copy of the MPL was not distributed with this
      4 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
      5 
      6 /*
      7 ** File:        pripv6.c
      8 ** Description: Support for various functions unique to IPv6
      9 */
     10 #include "primpl.h"
     11 #include <string.h>
     12 
     13 #if !defined(_PR_INET6) || defined(_PR_INET6_PROBE)
     14 
     15 static PRIOMethods ipv6_to_v4_tcpMethods;
     16 static PRIOMethods ipv6_to_v4_udpMethods;
     17 static PRDescIdentity _pr_ipv6_to_ipv4_id;
     18 extern PRBool IsValidNetAddr(const PRNetAddr* addr);
     19 extern const PRIPv6Addr _pr_in6addr_any;
     20 extern const PRIPv6Addr _pr_in6addr_loopback;
     21 
     22 /*
     23 * convert an IPv4-mapped IPv6 addr to an IPv4 addr
     24 */
     25 static void _PR_ConvertToIpv4NetAddr(const PRNetAddr* src_v6addr,
     26                                     PRNetAddr* dst_v4addr) {
     27  const PRUint8* srcp;
     28 
     29  PR_ASSERT(PR_AF_INET6 == src_v6addr->ipv6.family);
     30 
     31  if (PR_IsNetAddrType(src_v6addr, PR_IpAddrV4Mapped)) {
     32    srcp = src_v6addr->ipv6.ip.pr_s6_addr;
     33    memcpy((char*)&dst_v4addr->inet.ip, srcp + 12, 4);
     34  } else if (PR_IsNetAddrType(src_v6addr, PR_IpAddrAny)) {
     35    dst_v4addr->inet.ip = htonl(INADDR_ANY);
     36  } else if (PR_IsNetAddrType(src_v6addr, PR_IpAddrLoopback)) {
     37    dst_v4addr->inet.ip = htonl(INADDR_LOOPBACK);
     38  }
     39  dst_v4addr->inet.family = PR_AF_INET;
     40  dst_v4addr->inet.port = src_v6addr->ipv6.port;
     41 }
     42 
     43 /*
     44 * convert an IPv4 addr to an IPv4-mapped IPv6 addr
     45 */
     46 static void _PR_ConvertToIpv6NetAddr(const PRNetAddr* src_v4addr,
     47                                     PRNetAddr* dst_v6addr) {
     48  PRUint8* dstp;
     49 
     50  PR_ASSERT(PR_AF_INET == src_v4addr->inet.family);
     51  dst_v6addr->ipv6.family = PR_AF_INET6;
     52  dst_v6addr->ipv6.port = src_v4addr->inet.port;
     53 
     54  if (htonl(INADDR_ANY) == src_v4addr->inet.ip) {
     55    dst_v6addr->ipv6.ip = _pr_in6addr_any;
     56  } else {
     57    dstp = dst_v6addr->ipv6.ip.pr_s6_addr;
     58    memset(dstp, 0, 10);
     59    memset(dstp + 10, 0xff, 2);
     60    memcpy(dstp + 12, (char*)&src_v4addr->inet.ip, 4);
     61  }
     62 }
     63 
     64 static PRStatus PR_CALLBACK Ipv6ToIpv4SocketBind(PRFileDesc* fd,
     65                                                 const PRNetAddr* addr) {
     66  PRNetAddr tmp_ipv4addr;
     67  const PRNetAddr* tmp_addrp;
     68  PRFileDesc* lo = fd->lower;
     69 
     70  if (PR_AF_INET6 != addr->raw.family) {
     71    PR_SetError(PR_ADDRESS_NOT_SUPPORTED_ERROR, 0);
     72    return PR_FAILURE;
     73  }
     74  if (PR_IsNetAddrType(addr, PR_IpAddrV4Mapped) ||
     75      PR_IsNetAddrType(addr, PR_IpAddrAny)) {
     76    _PR_ConvertToIpv4NetAddr(addr, &tmp_ipv4addr);
     77    tmp_addrp = &tmp_ipv4addr;
     78  } else {
     79    PR_SetError(PR_NETWORK_UNREACHABLE_ERROR, 0);
     80    return PR_FAILURE;
     81  }
     82  return ((lo->methods->bind)(lo, tmp_addrp));
     83 }
     84 
     85 static PRStatus PR_CALLBACK Ipv6ToIpv4SocketConnect(PRFileDesc* fd,
     86                                                    const PRNetAddr* addr,
     87                                                    PRIntervalTime timeout) {
     88  PRNetAddr tmp_ipv4addr;
     89  const PRNetAddr* tmp_addrp;
     90 
     91  if (PR_AF_INET6 != addr->raw.family) {
     92    PR_SetError(PR_ADDRESS_NOT_SUPPORTED_ERROR, 0);
     93    return PR_FAILURE;
     94  }
     95  if (PR_IsNetAddrType(addr, PR_IpAddrV4Mapped) ||
     96      PR_IsNetAddrType(addr, PR_IpAddrLoopback)) {
     97    _PR_ConvertToIpv4NetAddr(addr, &tmp_ipv4addr);
     98    tmp_addrp = &tmp_ipv4addr;
     99  } else {
    100    PR_SetError(PR_NETWORK_UNREACHABLE_ERROR, 0);
    101    return PR_FAILURE;
    102  }
    103  return (fd->lower->methods->connect)(fd->lower, tmp_addrp, timeout);
    104 }
    105 
    106 static PRInt32 PR_CALLBACK Ipv6ToIpv4SocketSendTo(PRFileDesc* fd,
    107                                                  const void* buf,
    108                                                  PRInt32 amount, PRIntn flags,
    109                                                  const PRNetAddr* addr,
    110                                                  PRIntervalTime timeout) {
    111  PRNetAddr tmp_ipv4addr;
    112  const PRNetAddr* tmp_addrp;
    113 
    114  if (PR_AF_INET6 != addr->raw.family) {
    115    PR_SetError(PR_ADDRESS_NOT_SUPPORTED_ERROR, 0);
    116    return PR_FAILURE;
    117  }
    118  if (PR_IsNetAddrType(addr, PR_IpAddrV4Mapped) ||
    119      PR_IsNetAddrType(addr, PR_IpAddrLoopback)) {
    120    _PR_ConvertToIpv4NetAddr(addr, &tmp_ipv4addr);
    121    tmp_addrp = &tmp_ipv4addr;
    122  } else {
    123    PR_SetError(PR_NETWORK_UNREACHABLE_ERROR, 0);
    124    return PR_FAILURE;
    125  }
    126  return (fd->lower->methods->sendto)(fd->lower, buf, amount, flags, tmp_addrp,
    127                                      timeout);
    128 }
    129 
    130 static PRFileDesc* PR_CALLBACK Ipv6ToIpv4SocketAccept(PRFileDesc* fd,
    131                                                      PRNetAddr* addr,
    132                                                      PRIntervalTime timeout) {
    133  PRStatus rv;
    134  PRFileDesc* newfd;
    135  PRFileDesc* newstack;
    136  PRNetAddr tmp_ipv4addr;
    137  PRNetAddr* addrlower = NULL;
    138 
    139  PR_ASSERT(fd != NULL);
    140  PR_ASSERT(fd->lower != NULL);
    141 
    142  newstack = PR_NEW(PRFileDesc);
    143  if (NULL == newstack) {
    144    PR_SetError(PR_OUT_OF_MEMORY_ERROR, 0);
    145    return NULL;
    146  }
    147  *newstack = *fd; /* make a copy of the accepting layer */
    148 
    149  if (addr) {
    150    addrlower = &tmp_ipv4addr;
    151  }
    152  newfd = (fd->lower->methods->accept)(fd->lower, addrlower, timeout);
    153  if (NULL == newfd) {
    154    PR_DELETE(newstack);
    155    return NULL;
    156  }
    157  if (addr) {
    158    _PR_ConvertToIpv6NetAddr(&tmp_ipv4addr, addr);
    159  }
    160 
    161  rv = PR_PushIOLayer(newfd, PR_TOP_IO_LAYER, newstack);
    162  PR_ASSERT(PR_SUCCESS == rv);
    163  return newfd; /* that's it */
    164 }
    165 
    166 static PRInt32 PR_CALLBACK Ipv6ToIpv4SocketAcceptRead(PRFileDesc* sd,
    167                                                      PRFileDesc** nd,
    168                                                      PRNetAddr** ipv6_raddr,
    169                                                      void* buf, PRInt32 amount,
    170                                                      PRIntervalTime timeout) {
    171  PRInt32 nbytes;
    172  PRStatus rv;
    173  PRNetAddr tmp_ipv4addr;
    174  PRFileDesc* newstack;
    175 
    176  PR_ASSERT(sd != NULL);
    177  PR_ASSERT(sd->lower != NULL);
    178 
    179  newstack = PR_NEW(PRFileDesc);
    180  if (NULL == newstack) {
    181    PR_SetError(PR_OUT_OF_MEMORY_ERROR, 0);
    182    return -1;
    183  }
    184  *newstack = *sd; /* make a copy of the accepting layer */
    185 
    186  nbytes = sd->lower->methods->acceptread(sd->lower, nd, ipv6_raddr, buf,
    187                                          amount, timeout);
    188  if (-1 == nbytes) {
    189    PR_DELETE(newstack);
    190    return nbytes;
    191  }
    192  tmp_ipv4addr = **ipv6_raddr; /* copy */
    193  _PR_ConvertToIpv6NetAddr(&tmp_ipv4addr, *ipv6_raddr);
    194 
    195  /* this PR_PushIOLayer call cannot fail */
    196  rv = PR_PushIOLayer(*nd, PR_TOP_IO_LAYER, newstack);
    197  PR_ASSERT(PR_SUCCESS == rv);
    198  return nbytes;
    199 }
    200 
    201 static PRStatus PR_CALLBACK Ipv6ToIpv4SocketGetName(PRFileDesc* fd,
    202                                                    PRNetAddr* ipv6addr) {
    203  PRStatus result;
    204  PRNetAddr tmp_ipv4addr;
    205 
    206  result = (fd->lower->methods->getsockname)(fd->lower, &tmp_ipv4addr);
    207  if (PR_SUCCESS == result) {
    208    _PR_ConvertToIpv6NetAddr(&tmp_ipv4addr, ipv6addr);
    209    PR_ASSERT(IsValidNetAddr(ipv6addr) == PR_TRUE);
    210  }
    211  return result;
    212 }
    213 
    214 static PRStatus PR_CALLBACK Ipv6ToIpv4SocketGetPeerName(PRFileDesc* fd,
    215                                                        PRNetAddr* ipv6addr) {
    216  PRStatus result;
    217  PRNetAddr tmp_ipv4addr;
    218 
    219  result = (fd->lower->methods->getpeername)(fd->lower, &tmp_ipv4addr);
    220  if (PR_SUCCESS == result) {
    221    _PR_ConvertToIpv6NetAddr(&tmp_ipv4addr, ipv6addr);
    222    PR_ASSERT(IsValidNetAddr(ipv6addr) == PR_TRUE);
    223  }
    224  return result;
    225 }
    226 
    227 static PRInt32 PR_CALLBACK Ipv6ToIpv4SocketRecvFrom(PRFileDesc* fd, void* buf,
    228                                                    PRInt32 amount,
    229                                                    PRIntn flags,
    230                                                    PRNetAddr* ipv6addr,
    231                                                    PRIntervalTime timeout) {
    232  PRNetAddr tmp_ipv4addr;
    233  PRInt32 result;
    234 
    235  result = (fd->lower->methods->recvfrom)(fd->lower, buf, amount, flags,
    236                                          &tmp_ipv4addr, timeout);
    237  if (-1 != result) {
    238    _PR_ConvertToIpv6NetAddr(&tmp_ipv4addr, ipv6addr);
    239    PR_ASSERT(IsValidNetAddr(ipv6addr) == PR_TRUE);
    240  }
    241  return result;
    242 }
    243 
    244 #  if defined(_PR_INET6_PROBE)
    245 static PRBool ipv6_is_present;
    246 PR_EXTERN(PRBool) _pr_test_ipv6_socket(void);
    247 
    248 #    if !defined(_PR_INET6) && defined(_PR_HAVE_GETIPNODEBYNAME)
    249 extern PRStatus _pr_find_getipnodebyname(void);
    250 #    endif
    251 
    252 #    if !defined(_PR_INET6) && defined(_PR_HAVE_GETADDRINFO)
    253 extern PRStatus _pr_find_getaddrinfo(void);
    254 #    endif
    255 
    256 static PRBool _pr_probe_ipv6_presence(void) {
    257 #    if !defined(_PR_INET6) && defined(_PR_HAVE_GETIPNODEBYNAME)
    258  if (_pr_find_getipnodebyname() != PR_SUCCESS) {
    259    return PR_FALSE;
    260  }
    261 #    endif
    262 
    263 #    if !defined(_PR_INET6) && defined(_PR_HAVE_GETADDRINFO)
    264  if (_pr_find_getaddrinfo() != PR_SUCCESS) {
    265    return PR_FALSE;
    266  }
    267 #    endif
    268 
    269  return _pr_test_ipv6_socket();
    270 }
    271 #  endif /* _PR_INET6_PROBE */
    272 
    273 static PRCallOnceType _pr_init_ipv6_once;
    274 
    275 static PRStatus PR_CALLBACK _pr_init_ipv6(void) {
    276  const PRIOMethods* stubMethods;
    277 
    278 #  if defined(_PR_INET6_PROBE)
    279  ipv6_is_present = _pr_probe_ipv6_presence();
    280  if (ipv6_is_present) {
    281    return PR_SUCCESS;
    282  }
    283 #  endif
    284 
    285  _pr_ipv6_to_ipv4_id = PR_GetUniqueIdentity("Ipv6_to_Ipv4 layer");
    286  PR_ASSERT(PR_INVALID_IO_LAYER != _pr_ipv6_to_ipv4_id);
    287 
    288  stubMethods = PR_GetDefaultIOMethods();
    289 
    290  ipv6_to_v4_tcpMethods = *stubMethods; /* first get the entire batch */
    291  /* then override the ones we care about */
    292  ipv6_to_v4_tcpMethods.connect = Ipv6ToIpv4SocketConnect;
    293  ipv6_to_v4_tcpMethods.bind = Ipv6ToIpv4SocketBind;
    294  ipv6_to_v4_tcpMethods.accept = Ipv6ToIpv4SocketAccept;
    295  ipv6_to_v4_tcpMethods.acceptread = Ipv6ToIpv4SocketAcceptRead;
    296  ipv6_to_v4_tcpMethods.getsockname = Ipv6ToIpv4SocketGetName;
    297  ipv6_to_v4_tcpMethods.getpeername = Ipv6ToIpv4SocketGetPeerName;
    298  /*
    299      ipv6_to_v4_tcpMethods.getsocketoption = Ipv6ToIpv4GetSocketOption;
    300      ipv6_to_v4_tcpMethods.setsocketoption = Ipv6ToIpv4SetSocketOption;
    301  */
    302  ipv6_to_v4_udpMethods = *stubMethods; /* first get the entire batch */
    303  /* then override the ones we care about */
    304  ipv6_to_v4_udpMethods.connect = Ipv6ToIpv4SocketConnect;
    305  ipv6_to_v4_udpMethods.bind = Ipv6ToIpv4SocketBind;
    306  ipv6_to_v4_udpMethods.sendto = Ipv6ToIpv4SocketSendTo;
    307  ipv6_to_v4_udpMethods.recvfrom = Ipv6ToIpv4SocketRecvFrom;
    308  ipv6_to_v4_udpMethods.getsockname = Ipv6ToIpv4SocketGetName;
    309  ipv6_to_v4_udpMethods.getpeername = Ipv6ToIpv4SocketGetPeerName;
    310  /*
    311      ipv6_to_v4_udpMethods.getsocketoption = Ipv6ToIpv4GetSocketOption;
    312      ipv6_to_v4_udpMethods.setsocketoption = Ipv6ToIpv4SetSocketOption;
    313  */
    314  return PR_SUCCESS;
    315 }
    316 
    317 #  if defined(_PR_INET6_PROBE)
    318 PRBool _pr_ipv6_is_present(void) {
    319  if (PR_CallOnce(&_pr_init_ipv6_once, _pr_init_ipv6) != PR_SUCCESS) {
    320    return PR_FALSE;
    321  }
    322  return ipv6_is_present;
    323 }
    324 #  endif
    325 
    326 PR_IMPLEMENT(PRStatus) _pr_push_ipv6toipv4_layer(PRFileDesc* fd) {
    327  PRFileDesc* ipv6_fd = NULL;
    328 
    329  if (PR_CallOnce(&_pr_init_ipv6_once, _pr_init_ipv6) != PR_SUCCESS) {
    330    return PR_FAILURE;
    331  }
    332 
    333  /*
    334   * For platforms with no support for IPv6
    335   * create layered socket for IPv4-mapped IPv6 addresses
    336   */
    337  if (fd->methods->file_type == PR_DESC_SOCKET_TCP)
    338    ipv6_fd = PR_CreateIOLayerStub(_pr_ipv6_to_ipv4_id, &ipv6_to_v4_tcpMethods);
    339  else
    340    ipv6_fd = PR_CreateIOLayerStub(_pr_ipv6_to_ipv4_id, &ipv6_to_v4_udpMethods);
    341  if (NULL == ipv6_fd) {
    342    goto errorExit;
    343  }
    344  ipv6_fd->secret = NULL;
    345 
    346  if (PR_PushIOLayer(fd, PR_TOP_IO_LAYER, ipv6_fd) == PR_FAILURE) {
    347    goto errorExit;
    348  }
    349 
    350  return PR_SUCCESS;
    351 errorExit:
    352 
    353  if (ipv6_fd) {
    354    ipv6_fd->dtor(ipv6_fd);
    355  }
    356  return PR_FAILURE;
    357 }
    358 
    359 #endif /* !defined(_PR_INET6) || defined(_PR_INET6_PROBE) */