зеркало из https://github.com/github/putty.git
956 строки
22 KiB
C
956 строки
22 KiB
C
/*
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* Unix networking abstraction.
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <assert.h>
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#include <errno.h>
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#include <fcntl.h>
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#include <unistd.h>
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#include <sys/types.h>
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#include <sys/socket.h>
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#include <sys/ioctl.h>
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#include <arpa/inet.h>
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#include <netinet/in.h>
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#include <netinet/tcp.h>
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#include <netdb.h>
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#define DEFINE_PLUG_METHOD_MACROS
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#include "putty.h"
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#include "network.h"
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#include "tree234.h"
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struct Socket_tag {
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struct socket_function_table *fn;
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/* the above variable absolutely *must* be the first in this structure */
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char *error;
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int s;
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Plug plug;
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void *private_ptr;
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bufchain output_data;
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int connected;
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int writable;
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int frozen; /* this causes readability notifications to be ignored */
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int frozen_readable; /* this means we missed at least one readability
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* notification while we were frozen */
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int localhost_only; /* for listening sockets */
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char oobdata[1];
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int sending_oob;
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int oobpending; /* is there OOB data available to read? */
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int oobinline;
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int pending_error; /* in case send() returns error */
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int listener;
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};
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/*
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* We used to typedef struct Socket_tag *Socket.
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*
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* Since we have made the networking abstraction slightly more
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* abstract, Socket no longer means a tcp socket (it could mean
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* an ssl socket). So now we must use Actual_Socket when we know
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* we are talking about a tcp socket.
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*/
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typedef struct Socket_tag *Actual_Socket;
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struct SockAddr_tag {
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char *error;
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/* address family this belongs to, AF_INET for IPv4, AF_INET6 for IPv6. */
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int family;
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unsigned long address; /* Address IPv4 style. */
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#ifdef IPV6
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struct addrinfo *ai; /* Address IPv6 style. */
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#endif
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};
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static tree234 *sktree;
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static int cmpfortree(void *av, void *bv)
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{
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Actual_Socket a = (Actual_Socket) av, b = (Actual_Socket) bv;
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int as = a->s, bs = b->s;
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if (as < bs)
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return -1;
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if (as > bs)
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return +1;
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return 0;
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}
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static int cmpforsearch(void *av, void *bv)
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{
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Actual_Socket b = (Actual_Socket) bv;
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int as = (int) av, bs = b->s;
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if (as < bs)
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return -1;
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if (as > bs)
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return +1;
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return 0;
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}
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void sk_init(void)
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{
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sktree = newtree234(cmpfortree);
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}
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void sk_cleanup(void)
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{
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Actual_Socket s;
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int i;
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if (sktree) {
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for (i = 0; (s = index234(sktree, i)) != NULL; i++) {
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close(s->s);
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}
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}
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}
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char *error_string(int error)
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{
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return strerror(error);
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}
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SockAddr sk_namelookup(char *host, char **canonicalname)
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{
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SockAddr ret = smalloc(sizeof(struct SockAddr_tag));
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unsigned long a;
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struct hostent *h = NULL;
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char realhost[8192];
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/* Clear the structure and default to IPv4. */
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memset(ret, 0, sizeof(struct SockAddr_tag));
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ret->family = 0; /* We set this one when we have resolved the host. */
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*realhost = '\0';
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ret->error = NULL;
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if ((a = inet_addr(host)) == (unsigned long) INADDR_NONE) {
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#ifdef IPV6
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if (getaddrinfo(host, NULL, NULL, &ret->ai) == 0) {
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ret->family = ret->ai->ai_family;
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} else
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#endif
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{
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/*
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* Otherwise use the IPv4-only gethostbyname... (NOTE:
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* we don't use gethostbyname as a fallback!)
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*/
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if (ret->family == 0) {
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/*debug(("Resolving \"%s\" with gethostbyname() (IPv4 only)...\n", host)); */
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if ( (h = gethostbyname(host)) )
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ret->family = AF_INET;
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}
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if (ret->family == 0) {
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ret->error = (h_errno == HOST_NOT_FOUND ||
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h_errno == NO_DATA ||
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h_errno == NO_ADDRESS ? "Host does not exist" :
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h_errno == TRY_AGAIN ?
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"Temporary name service failure" :
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"gethostbyname: unknown error");
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return ret;
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}
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}
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#ifdef IPV6
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/* If we got an address info use that... */
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if (ret->ai) {
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/* Are we in IPv4 fallback mode? */
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/* We put the IPv4 address into the a variable so we can further-on use the IPv4 code... */
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if (ret->family == AF_INET)
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memcpy(&a,
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(char *) &((struct sockaddr_in *) ret->ai->
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ai_addr)->sin_addr, sizeof(a));
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/* Now let's find that canonicalname... */
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if (getnameinfo((struct sockaddr *) ret->ai->ai_addr,
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ret->family ==
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AF_INET ? sizeof(struct sockaddr_in) :
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sizeof(struct sockaddr_in6), realhost,
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sizeof(realhost), NULL, 0, 0) != 0) {
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strncpy(realhost, host, sizeof(realhost));
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}
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}
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/* We used the IPv4-only gethostbyname()... */
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else
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#endif
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{
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memcpy(&a, h->h_addr, sizeof(a));
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/* This way we are always sure the h->h_name is valid :) */
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strncpy(realhost, h->h_name, sizeof(realhost));
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}
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} else {
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/*
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* This must be a numeric IPv4 address because it caused a
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* success return from inet_addr.
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*/
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ret->family = AF_INET;
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strncpy(realhost, host, sizeof(realhost));
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}
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ret->address = ntohl(a);
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realhost[lenof(realhost)-1] = '\0';
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*canonicalname = smalloc(1+strlen(realhost));
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strcpy(*canonicalname, realhost);
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return ret;
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}
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void sk_getaddr(SockAddr addr, char *buf, int buflen)
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{
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#ifdef IPV6
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if (addr->family == AF_INET) {
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#endif
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struct in_addr a;
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a.s_addr = htonl(addr->address);
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strncpy(buf, inet_ntoa(a), buflen);
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#ifdef IPV6
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} else {
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FIXME; /* I don't know how to get a text form of an IPv6 address. */
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}
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#endif
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}
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int sk_addrtype(SockAddr addr)
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{
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return (addr->family == AF_INET ? ADDRTYPE_IPV4 : ADDRTYPE_IPV6);
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}
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void sk_addrcopy(SockAddr addr, char *buf)
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{
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#ifdef IPV6
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if (addr->family == AF_INET) {
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#endif
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struct in_addr a;
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a.s_addr = htonl(addr->address);
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memcpy(buf, (char*) &a.s_addr, 4);
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#ifdef IPV6
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} else {
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memcpy(buf, (char*) addr->ai, 16);
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}
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#endif
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}
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void sk_addr_free(SockAddr addr)
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{
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sfree(addr);
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}
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static Plug sk_tcp_plug(Socket sock, Plug p)
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{
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Actual_Socket s = (Actual_Socket) sock;
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Plug ret = s->plug;
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if (p)
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s->plug = p;
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return ret;
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}
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static void sk_tcp_flush(Socket s)
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{
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/*
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* We send data to the socket as soon as we can anyway,
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* so we don't need to do anything here. :-)
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*/
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}
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static void sk_tcp_close(Socket s);
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static int sk_tcp_write(Socket s, char *data, int len);
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static int sk_tcp_write_oob(Socket s, char *data, int len);
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static void sk_tcp_set_private_ptr(Socket s, void *ptr);
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static void *sk_tcp_get_private_ptr(Socket s);
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static void sk_tcp_set_frozen(Socket s, int is_frozen);
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static char *sk_tcp_socket_error(Socket s);
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Socket sk_register(void *sock, Plug plug)
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{
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static struct socket_function_table fn_table = {
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sk_tcp_plug,
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sk_tcp_close,
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sk_tcp_write,
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sk_tcp_write_oob,
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sk_tcp_flush,
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sk_tcp_set_private_ptr,
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sk_tcp_get_private_ptr,
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sk_tcp_set_frozen,
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sk_tcp_socket_error
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};
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Actual_Socket ret;
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/*
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* Create Socket structure.
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*/
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ret = smalloc(sizeof(struct Socket_tag));
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ret->fn = &fn_table;
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ret->error = NULL;
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ret->plug = plug;
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bufchain_init(&ret->output_data);
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ret->writable = 1; /* to start with */
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ret->sending_oob = 0;
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ret->frozen = 1;
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ret->frozen_readable = 0;
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ret->localhost_only = 0; /* unused, but best init anyway */
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ret->pending_error = 0;
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ret->oobpending = FALSE;
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ret->listener = 0;
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ret->s = (int)sock;
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if (ret->s < 0) {
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ret->error = error_string(errno);
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return (Socket) ret;
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}
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ret->oobinline = 0;
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add234(sktree, ret);
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return (Socket) ret;
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}
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Socket sk_new(SockAddr addr, int port, int privport, int oobinline,
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int nodelay, Plug plug)
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{
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static struct socket_function_table fn_table = {
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sk_tcp_plug,
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sk_tcp_close,
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sk_tcp_write,
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sk_tcp_write_oob,
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sk_tcp_flush,
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sk_tcp_set_private_ptr,
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sk_tcp_get_private_ptr,
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sk_tcp_set_frozen,
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sk_tcp_socket_error
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};
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int s;
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#ifdef IPV6
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struct sockaddr_in6 a6;
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#endif
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struct sockaddr_in a;
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int err;
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Actual_Socket ret;
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short localport;
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/*
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* Create Socket structure.
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*/
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ret = smalloc(sizeof(struct Socket_tag));
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ret->fn = &fn_table;
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ret->error = NULL;
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ret->plug = plug;
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bufchain_init(&ret->output_data);
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ret->connected = 0; /* to start with */
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ret->writable = 0; /* to start with */
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ret->sending_oob = 0;
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ret->frozen = 0;
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ret->frozen_readable = 0;
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ret->localhost_only = 0; /* unused, but best init anyway */
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ret->pending_error = 0;
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ret->oobpending = FALSE;
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ret->listener = 0;
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/*
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* Open socket.
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*/
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s = socket(addr->family, SOCK_STREAM, 0);
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ret->s = s;
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if (s < 0) {
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ret->error = error_string(errno);
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return (Socket) ret;
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}
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ret->oobinline = oobinline;
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if (oobinline) {
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int b = TRUE;
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setsockopt(s, SOL_SOCKET, SO_OOBINLINE, (void *) &b, sizeof(b));
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}
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if (nodelay) {
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int b = TRUE;
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setsockopt(s, IPPROTO_TCP, TCP_NODELAY, (void *) &b, sizeof(b));
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}
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/*
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* Bind to local address.
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*/
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if (privport)
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localport = 1023; /* count from 1023 downwards */
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else
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localport = 0; /* just use port 0 (ie kernel picks) */
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/* Loop round trying to bind */
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while (1) {
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int retcode;
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#ifdef IPV6
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if (addr->family == AF_INET6) {
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memset(&a6, 0, sizeof(a6));
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a6.sin6_family = AF_INET6;
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/*a6.sin6_addr = in6addr_any; *//* == 0 */
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a6.sin6_port = htons(localport);
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} else
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#endif
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{
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a.sin_family = AF_INET;
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a.sin_addr.s_addr = htonl(INADDR_ANY);
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a.sin_port = htons(localport);
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}
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#ifdef IPV6
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retcode = bind(s, (addr->family == AF_INET6 ?
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(struct sockaddr *) &a6 :
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(struct sockaddr *) &a),
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(addr->family ==
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AF_INET6 ? sizeof(a6) : sizeof(a)));
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#else
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retcode = bind(s, (struct sockaddr *) &a, sizeof(a));
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#endif
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if (retcode >= 0) {
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err = 0;
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break; /* done */
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} else {
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err = errno;
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if (err != EADDRINUSE) /* failed, for a bad reason */
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break;
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}
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if (localport == 0)
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break; /* we're only looping once */
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localport--;
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if (localport == 0)
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break; /* we might have got to the end */
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}
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if (err) {
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ret->error = error_string(err);
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return (Socket) ret;
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}
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/*
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* Connect to remote address.
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*/
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#ifdef IPV6
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if (addr->family == AF_INET6) {
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memset(&a, 0, sizeof(a));
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a6.sin6_family = AF_INET6;
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a6.sin6_port = htons((short) port);
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a6.sin6_addr =
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((struct sockaddr_in6 *) addr->ai->ai_addr)->sin6_addr;
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} else
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#endif
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{
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a.sin_family = AF_INET;
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a.sin_addr.s_addr = htonl(addr->address);
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a.sin_port = htons((short) port);
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}
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if ((
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#ifdef IPV6
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connect(s, ((addr->family == AF_INET6) ?
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(struct sockaddr *) &a6 : (struct sockaddr *) &a),
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(addr->family == AF_INET6) ? sizeof(a6) : sizeof(a))
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#else
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connect(s, (struct sockaddr *) &a, sizeof(a))
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#endif
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) < 0) {
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/*
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* FIXME: We are prepared to receive EWOULDBLOCK here,
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* because we might want the connection to be made
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* asynchronously; but how do we actually arrange this in
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* Unix? I forget.
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*/
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if ( errno != EWOULDBLOCK ) {
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ret->error = error_string(errno);
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return (Socket) ret;
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}
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} else {
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/*
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* If we _don't_ get EWOULDBLOCK, the connect has completed
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* and we should set the socket as connected and writable.
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*/
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ret->connected = 1;
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ret->writable = 1;
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}
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add234(sktree, ret);
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return (Socket) ret;
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}
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Socket sk_newlistener(int port, Plug plug, int local_host_only)
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{
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static struct socket_function_table fn_table = {
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sk_tcp_plug,
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sk_tcp_close,
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sk_tcp_write,
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sk_tcp_write_oob,
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sk_tcp_flush,
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sk_tcp_set_private_ptr,
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sk_tcp_get_private_ptr,
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sk_tcp_set_frozen,
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sk_tcp_socket_error
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};
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int s;
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#ifdef IPV6
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struct sockaddr_in6 a6;
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#endif
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struct sockaddr_in a;
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int err;
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Actual_Socket ret;
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int retcode;
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int on = 1;
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/*
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* Create Socket structure.
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*/
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ret = smalloc(sizeof(struct Socket_tag));
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ret->fn = &fn_table;
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ret->error = NULL;
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ret->plug = plug;
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bufchain_init(&ret->output_data);
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ret->writable = 0; /* to start with */
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ret->sending_oob = 0;
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ret->frozen = 0;
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ret->frozen_readable = 0;
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ret->localhost_only = local_host_only;
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ret->pending_error = 0;
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ret->oobpending = FALSE;
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ret->listener = 1;
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/*
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* Open socket.
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*/
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s = socket(AF_INET, SOCK_STREAM, 0);
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ret->s = s;
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if (s < 0) {
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ret->error = error_string(errno);
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return (Socket) ret;
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}
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ret->oobinline = 0;
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setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (const char *)&on, sizeof(on));
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#ifdef IPV6
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if (addr->family == AF_INET6) {
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memset(&a6, 0, sizeof(a6));
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a6.sin6_family = AF_INET6;
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if (local_host_only)
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a6.sin6_addr = in6addr_loopback;
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else
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a6.sin6_addr = in6addr_any;
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a6.sin6_port = htons(port);
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} else
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#endif
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{
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a.sin_family = AF_INET;
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if (local_host_only)
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a.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
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else
|
|
a.sin_addr.s_addr = htonl(INADDR_ANY);
|
|
a.sin_port = htons((short)port);
|
|
}
|
|
#ifdef IPV6
|
|
retcode = bind(s, (addr->family == AF_INET6 ?
|
|
(struct sockaddr *) &a6 :
|
|
(struct sockaddr *) &a),
|
|
(addr->family ==
|
|
AF_INET6 ? sizeof(a6) : sizeof(a)));
|
|
#else
|
|
retcode = bind(s, (struct sockaddr *) &a, sizeof(a));
|
|
#endif
|
|
if (retcode >= 0) {
|
|
err = 0;
|
|
} else {
|
|
err = errno;
|
|
}
|
|
|
|
if (err) {
|
|
ret->error = error_string(err);
|
|
return (Socket) ret;
|
|
}
|
|
|
|
|
|
if (listen(s, SOMAXCONN) < 0) {
|
|
close(s);
|
|
ret->error = error_string(errno);
|
|
return (Socket) ret;
|
|
}
|
|
|
|
add234(sktree, ret);
|
|
|
|
return (Socket) ret;
|
|
}
|
|
|
|
static void sk_tcp_close(Socket sock)
|
|
{
|
|
Actual_Socket s = (Actual_Socket) sock;
|
|
|
|
del234(sktree, s);
|
|
close(s->s);
|
|
sfree(s);
|
|
}
|
|
|
|
/*
|
|
* The function which tries to send on a socket once it's deemed
|
|
* writable.
|
|
*/
|
|
void try_send(Actual_Socket s)
|
|
{
|
|
while (s->sending_oob || bufchain_size(&s->output_data) > 0) {
|
|
int nsent;
|
|
int err;
|
|
void *data;
|
|
int len, urgentflag;
|
|
|
|
if (s->sending_oob) {
|
|
urgentflag = MSG_OOB;
|
|
len = s->sending_oob;
|
|
data = &s->oobdata;
|
|
} else {
|
|
urgentflag = 0;
|
|
bufchain_prefix(&s->output_data, &data, &len);
|
|
}
|
|
nsent = send(s->s, data, len, urgentflag);
|
|
noise_ultralight(nsent);
|
|
if (nsent <= 0) {
|
|
err = (nsent < 0 ? errno : 0);
|
|
if (err == EWOULDBLOCK) {
|
|
/*
|
|
* Perfectly normal: we've sent all we can for the moment.
|
|
*/
|
|
s->writable = FALSE;
|
|
return;
|
|
} else if (nsent == 0 ||
|
|
err == ECONNABORTED || err == ECONNRESET) {
|
|
/*
|
|
* If send() returns CONNABORTED or CONNRESET, we
|
|
* unfortunately can't just call plug_closing(),
|
|
* because it's quite likely that we're currently
|
|
* _in_ a call from the code we'd be calling back
|
|
* to, so we'd have to make half the SSH code
|
|
* reentrant. Instead we flag a pending error on
|
|
* the socket, to be dealt with (by calling
|
|
* plug_closing()) at some suitable future moment.
|
|
*/
|
|
s->pending_error = err;
|
|
return;
|
|
} else {
|
|
/* We're inside the Unix frontend here, so we know
|
|
* that the frontend handle is unnecessary. */
|
|
logevent(NULL, error_string(err));
|
|
fatalbox("%s", error_string(err));
|
|
}
|
|
} else {
|
|
if (s->sending_oob) {
|
|
if (nsent < len) {
|
|
memmove(s->oobdata, s->oobdata+nsent, len-nsent);
|
|
s->sending_oob = len - nsent;
|
|
} else {
|
|
s->sending_oob = 0;
|
|
}
|
|
} else {
|
|
bufchain_consume(&s->output_data, nsent);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
static int sk_tcp_write(Socket sock, char *buf, int len)
|
|
{
|
|
Actual_Socket s = (Actual_Socket) sock;
|
|
|
|
/*
|
|
* Add the data to the buffer list on the socket.
|
|
*/
|
|
bufchain_add(&s->output_data, buf, len);
|
|
|
|
/*
|
|
* Now try sending from the start of the buffer list.
|
|
*/
|
|
if (s->writable)
|
|
try_send(s);
|
|
|
|
return bufchain_size(&s->output_data);
|
|
}
|
|
|
|
static int sk_tcp_write_oob(Socket sock, char *buf, int len)
|
|
{
|
|
Actual_Socket s = (Actual_Socket) sock;
|
|
|
|
/*
|
|
* Replace the buffer list on the socket with the data.
|
|
*/
|
|
bufchain_clear(&s->output_data);
|
|
assert(len <= sizeof(s->oobdata));
|
|
memcpy(s->oobdata, buf, len);
|
|
s->sending_oob = len;
|
|
|
|
/*
|
|
* Now try sending from the start of the buffer list.
|
|
*/
|
|
if (s->writable)
|
|
try_send(s);
|
|
|
|
return s->sending_oob;
|
|
}
|
|
|
|
int select_result(int fd, int event)
|
|
{
|
|
int ret;
|
|
int err;
|
|
char buf[20480]; /* nice big buffer for plenty of speed */
|
|
Actual_Socket s;
|
|
u_long atmark;
|
|
|
|
/* Find the Socket structure */
|
|
s = find234(sktree, (void *) fd, cmpforsearch);
|
|
if (!s)
|
|
return 1; /* boggle */
|
|
|
|
noise_ultralight(event);
|
|
|
|
switch (event) {
|
|
#ifdef FIXME_NONBLOCKING_CONNECTIONS
|
|
case FIXME: /* connected */
|
|
s->connected = s->writable = 1;
|
|
break;
|
|
#endif
|
|
case 4: /* exceptional */
|
|
if (!s->oobinline) {
|
|
/*
|
|
* On a non-oobinline socket, this indicates that we
|
|
* can immediately perform an OOB read and get back OOB
|
|
* data, which we will send to the back end with
|
|
* type==2 (urgent data).
|
|
*/
|
|
ret = recv(s->s, buf, sizeof(buf), MSG_OOB);
|
|
noise_ultralight(ret);
|
|
if (ret <= 0) {
|
|
char *str = (ret == 0 ? "Internal networking trouble" :
|
|
error_string(errno));
|
|
/* We're inside the Unix frontend here, so we know
|
|
* that the frontend handle is unnecessary. */
|
|
logevent(NULL, str);
|
|
fatalbox("%s", str);
|
|
} else {
|
|
return plug_receive(s->plug, 2, buf, ret);
|
|
}
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* If we reach here, this is an oobinline socket, which
|
|
* means we should set s->oobpending and then deal with it
|
|
* when we get called for the readability event (which
|
|
* should also occur).
|
|
*/
|
|
s->oobpending = TRUE;
|
|
break;
|
|
case 1: /* readable; also acceptance */
|
|
if (s->listener) {
|
|
/*
|
|
* On a listening socket, the readability event means a
|
|
* connection is ready to be accepted.
|
|
*/
|
|
struct sockaddr_in isa;
|
|
int addrlen = sizeof(struct sockaddr_in);
|
|
int t; /* socket of connection */
|
|
|
|
memset(&isa, 0, sizeof(struct sockaddr_in));
|
|
err = 0;
|
|
t = accept(s->s,(struct sockaddr *)&isa,&addrlen);
|
|
if (t < 0) {
|
|
break;
|
|
}
|
|
|
|
if (s->localhost_only &&
|
|
ntohl(isa.sin_addr.s_addr) != INADDR_LOOPBACK) {
|
|
close(t); /* someone let nonlocal through?! */
|
|
} else if (plug_accepting(s->plug, (void*)t)) {
|
|
close(t); /* denied or error */
|
|
}
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* If we reach here, this is not a listening socket, so
|
|
* readability really means readability.
|
|
*/
|
|
|
|
/* In the case the socket is still frozen, we don't even bother */
|
|
if (s->frozen) {
|
|
s->frozen_readable = 1;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* We have received data on the socket. For an oobinline
|
|
* socket, this might be data _before_ an urgent pointer,
|
|
* in which case we send it to the back end with type==1
|
|
* (data prior to urgent).
|
|
*/
|
|
if (s->oobinline && s->oobpending) {
|
|
atmark = 1;
|
|
if (ioctl(s->s, SIOCATMARK, &atmark) == 0 && atmark)
|
|
s->oobpending = FALSE; /* clear this indicator */
|
|
} else
|
|
atmark = 1;
|
|
|
|
ret = recv(s->s, buf, s->oobpending ? 1 : sizeof(buf), 0);
|
|
noise_ultralight(ret);
|
|
if (ret < 0) {
|
|
if (errno == EWOULDBLOCK) {
|
|
break;
|
|
}
|
|
}
|
|
if (ret < 0) {
|
|
return plug_closing(s->plug, error_string(errno), errno, 0);
|
|
} else if (0 == ret) {
|
|
return plug_closing(s->plug, NULL, 0, 0);
|
|
} else {
|
|
return plug_receive(s->plug, atmark ? 0 : 1, buf, ret);
|
|
}
|
|
break;
|
|
case 2: /* writable */
|
|
{
|
|
int bufsize_before, bufsize_after;
|
|
s->writable = 1;
|
|
bufsize_before = s->sending_oob + bufchain_size(&s->output_data);
|
|
try_send(s);
|
|
bufsize_after = s->sending_oob + bufchain_size(&s->output_data);
|
|
if (bufsize_after < bufsize_before)
|
|
plug_sent(s->plug, bufsize_after);
|
|
}
|
|
break;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* Deal with socket errors detected in try_send().
|
|
*/
|
|
void net_pending_errors(void)
|
|
{
|
|
int i;
|
|
Actual_Socket s;
|
|
|
|
/*
|
|
* This might be a fiddly business, because it's just possible
|
|
* that handling a pending error on one socket might cause
|
|
* others to be closed. (I can't think of any reason this might
|
|
* happen in current SSH implementation, but to maintain
|
|
* generality of this network layer I'll assume the worst.)
|
|
*
|
|
* So what we'll do is search the socket list for _one_ socket
|
|
* with a pending error, and then handle it, and then search
|
|
* the list again _from the beginning_. Repeat until we make a
|
|
* pass with no socket errors present. That way we are
|
|
* protected against the socket list changing under our feet.
|
|
*/
|
|
|
|
do {
|
|
for (i = 0; (s = index234(sktree, i)) != NULL; i++) {
|
|
if (s->pending_error) {
|
|
/*
|
|
* An error has occurred on this socket. Pass it to the
|
|
* plug.
|
|
*/
|
|
plug_closing(s->plug, error_string(s->pending_error),
|
|
s->pending_error, 0);
|
|
break;
|
|
}
|
|
}
|
|
} while (s);
|
|
}
|
|
|
|
/*
|
|
* Each socket abstraction contains a `void *' private field in
|
|
* which the client can keep state.
|
|
*/
|
|
static void sk_tcp_set_private_ptr(Socket sock, void *ptr)
|
|
{
|
|
Actual_Socket s = (Actual_Socket) sock;
|
|
s->private_ptr = ptr;
|
|
}
|
|
|
|
static void *sk_tcp_get_private_ptr(Socket sock)
|
|
{
|
|
Actual_Socket s = (Actual_Socket) sock;
|
|
return s->private_ptr;
|
|
}
|
|
|
|
/*
|
|
* Special error values are returned from sk_namelookup and sk_new
|
|
* if there's a problem. These functions extract an error message,
|
|
* or return NULL if there's no problem.
|
|
*/
|
|
char *sk_addr_error(SockAddr addr)
|
|
{
|
|
return addr->error;
|
|
}
|
|
static char *sk_tcp_socket_error(Socket sock)
|
|
{
|
|
Actual_Socket s = (Actual_Socket) sock;
|
|
return s->error;
|
|
}
|
|
|
|
static void sk_tcp_set_frozen(Socket sock, int is_frozen)
|
|
{
|
|
Actual_Socket s = (Actual_Socket) sock;
|
|
if (s->frozen == is_frozen)
|
|
return;
|
|
s->frozen = is_frozen;
|
|
if (!is_frozen && s->frozen_readable) {
|
|
char c;
|
|
recv(s->s, &c, 1, MSG_PEEK);
|
|
}
|
|
s->frozen_readable = 0;
|
|
}
|
|
|
|
/*
|
|
* For Unix select()-based frontends: enumerate all sockets
|
|
* currently active, and state whether we currently wish to receive
|
|
* select events on them for reading, writing and exceptional
|
|
* status.
|
|
*/
|
|
static void set_rwx(Actual_Socket s, int *rwx)
|
|
{
|
|
int val = 0;
|
|
if (s->connected && !s->frozen)
|
|
val |= 1 | 4; /* read, except */
|
|
if (bufchain_size(&s->output_data))
|
|
val |= 2; /* write */
|
|
if (s->listener)
|
|
val |= 1; /* read == accept */
|
|
*rwx = val;
|
|
}
|
|
|
|
int first_socket(int *state, int *rwx)
|
|
{
|
|
Actual_Socket s;
|
|
*state = 0;
|
|
s = index234(sktree, (*state)++);
|
|
if (s)
|
|
set_rwx(s, rwx);
|
|
return s ? s->s : -1;
|
|
}
|
|
|
|
int next_socket(int *state, int *rwx)
|
|
{
|
|
Actual_Socket s = index234(sktree, (*state)++);
|
|
if (s)
|
|
set_rwx(s, rwx);
|
|
return s ? s->s : -1;
|
|
}
|
|
|
|
int net_service_lookup(char *service)
|
|
{
|
|
struct servent *se;
|
|
se = getservbyname(service, NULL);
|
|
if (se != NULL)
|
|
return ntohs(se->s_port);
|
|
else
|
|
return 0;
|
|
}
|