LXR toybox/lib/net.c

   1#include "toys.h"
   2
   3int xsocket(int domain, int type, int protocol)
   4{
   5  int fd = socket(domain, type, protocol);
   6
   7  if (fd < 0) perror_exit("socket %x %x", type, protocol);
   8  fcntl(fd, F_SETFD, FD_CLOEXEC);
   9
  10  return fd;
  11}
  12
  13void xsetsockopt(int fd, int level, int opt, void *val, socklen_t len)
  14{
  15  if (-1 == setsockopt(fd, level, opt, val, len)) perror_exit("setsockopt");
  16}
  17
  18// if !host bind to all local interfaces
  19struct addrinfo *xgetaddrinfo(char *host, char *port, int family, int socktype,
  20  int protocol, int flags)
  21{
  22  struct addrinfo info, *ai;
  23  int rc;
  24
  25  memset(&info, 0, sizeof(struct addrinfo));
  26  info.ai_family = family;
  27  info.ai_socktype = socktype;
  28  info.ai_protocol = protocol;
  29  info.ai_flags = flags;
  30  if (!host) info.ai_flags |= AI_PASSIVE;
  31
  32  rc = getaddrinfo(host, port, &info, &ai);
  33  if (rc || !ai)
  34    error_exit("%s%s%s: %s", host ? host : "*", port ? ":" : "",
  35      port ? port : "", rc ? gai_strerror(rc) : "not found");
  36
  37  return ai;
  38}
  39
  40static int xconnbind(struct addrinfo *ai_arg, int dobind)
  41{
  42  struct addrinfo *ai;
  43  int fd = -1, one = 1;
  44
  45  // Try all the returned addresses. Report errors if last entry can't connect.
  46  for (ai = ai_arg; ai; ai = ai->ai_next) {
  47    fd = (ai->ai_next ? socket : xsocket)(ai->ai_family, ai->ai_socktype,
  48      ai->ai_protocol);
  49    xsetsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
  50    if (!(dobind ? bind : connect)(fd, ai->ai_addr, ai->ai_addrlen)) break;
  51    else if (!ai->ai_next) perror_exit_raw(dobind ? "bind" : "connect");
  52    close(fd);
  53  }
  54  freeaddrinfo(ai_arg);
  55
  56  return fd;
  57}
  58
  59int xconnectany(struct addrinfo *ai)
  60{
  61  return xconnbind(ai, 0);
  62}
  63
  64
  65int xbindany(struct addrinfo *ai)
  66{
  67  return xconnbind(ai, 1);
  68}
  69
  70void xbind(int fd, const struct sockaddr *sa, socklen_t len)
  71{
  72  if (bind(fd, sa, len)) perror_exit("bind");
  73}
  74
  75void xconnect(int fd, const struct sockaddr *sa, socklen_t len)
  76{
  77  if (connect(fd, sa, len)) perror_exit("connect");
  78}
  79
  80int xpoll(struct pollfd *fds, int nfds, int timeout)
  81{
  82  int i;
  83  long long now, then = timeout>0 ? millitime() : 0;
  84
  85  for (;;) {
  86    if (0<=(i = poll(fds, nfds, timeout)) || toys.signal) return i;
  87    if (errno != EINTR && errno != ENOMEM) perror_exit("xpoll");
  88    else {
  89      now = millitime();
  90      timeout -= now-then;
  91      then = now;
  92    }
  93  }
  94}
  95
  96// Loop forwarding data from in1 to out1 and in2 to out2, handling
  97// half-connection shutdown. timeouts return if no data for X ms.
  98// Returns 0: both closed, 1 shutdown_timeout, 2 timeout
  99int pollinate(int in1, int in2, int out1, int out2, int timeout, int shutdown_timeout)
 100{
 101  struct pollfd pollfds[2];
 102  int i, pollcount = 2;
 103
 104  memset(pollfds, 0, 2*sizeof(struct pollfd));
 105  pollfds[0].events = pollfds[1].events = POLLIN;
 106  pollfds[0].fd = in1;
 107  pollfds[1].fd = in2;
 108
 109  // Poll loop copying data from each fd to the other one.
 110  for (;;) {
 111    if (!xpoll(pollfds, pollcount, timeout)) return pollcount;
 112
 113    for (i=0; i<pollcount; i++) {
 114      if (pollfds[i].revents & POLLIN) {
 115        int len = read(pollfds[i].fd, libbuf, sizeof(libbuf));
 116        if (len<1) pollfds[i].revents = POLLHUP;
 117        else xwrite(i ? out2 : out1, libbuf, len);
 118      }
 119      if (pollfds[i].revents & POLLHUP) {
 120        // Close half-connection.  This is needed for things like
 121        // "echo GET / | netcat landley.net 80"
 122        // Note that in1 closing triggers timeout, in2 returns now.
 123        if (i) {
 124          shutdown(pollfds[0].fd, SHUT_WR);
 125          pollcount--;
 126          timeout = shutdown_timeout;
 127        } else return 0;
 128      }
 129    }
 130  }
 131}
 132
 133// Return converted ipv4/ipv6 numeric address in libbuf
 134char *ntop(struct sockaddr *sa)
 135{
 136  void *addr;
 137
 138  if (sa->sa_family == AF_INET) addr = &((struct sockaddr_in *)sa)->sin_addr;
 139  else addr = &((struct sockaddr_in6 *)sa)->sin6_addr;
 140
 141  inet_ntop(sa->sa_family, addr, libbuf, sizeof(libbuf));
 142
 143  return libbuf;
 144}
 145
 146void xsendto(int sockfd, void *buf, size_t len, struct sockaddr *dest)
 147{
 148  int rc = sendto(sockfd, buf, len, 0, dest,
 149    dest->sa_family == AF_INET ? sizeof(struct sockaddr_in) :
 150      sizeof(struct sockaddr_in6));
 151
 152  if (rc != len) perror_exit("sendto");
 153}
 154
 155// xrecvfrom with timeout in milliseconds
 156int xrecvwait(int fd, char *buf, int len, union socksaddr *sa, int timeout)
 157{
 158  socklen_t sl = sizeof(*sa);
 159
 160  if (timeout >= 0) {
 161    struct pollfd pfd;
 162
 163    pfd.fd = fd;
 164    pfd.events = POLLIN;
 165    if (!xpoll(&pfd, 1, timeout)) return 0;
 166  }
 167
 168  len = recvfrom(fd, buf, len, 0, (void *)sa, &sl);
 169  if (len<0) perror_exit("recvfrom");
 170
 171  return len;
 172}
 173