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diff --git a/src/dnsclient.c b/src/dnsclient.c
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+/* $Id: dnsclient.c,v 1.1 2002-05-23 04:40:06 rjkaes Exp $
+ *
+ * Create the dnsserver child process, and then include functions to
+ * retrieve IP addresses or host names. These functions are required
+ * since the traditional gethostbyaddr() and getaddrbyname() functions
+ * are not thread reentrant. By spawning a child process the blocking
+ * has been moved outside the threads.
+ *
+ * Copyright (C) 2002 Robert James Kaes (rjkaes@flarenet.com)
+ *
+ * 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, 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.
+ */
+
+#include "tinyproxy.h"
+
+#include "dnsclient.h"
+#include "heap.h"
+#include "log.h"
+#include "network.h"
+#include "text.h"
+
+/*
+ * Static variable which holds the "dnsserver" process.
+ */
+static pid_t dnsserver_process;
+
+/*
+ * Hold the location of the Unix socket for client communication.
+ */
+static char* unix_socket_loc;
+
+/*
+ * Fork a copy of the "dnsserver" program. Two arguments are used
+ * by this function: 'dnsserver_location' is the complete path to the
+ * dnsserver execuatable; 'path' is the absolute path used by the
+ * Unix socket.
+ */
+int
+start_dnsserver(const char* dnsserver_location, const char* path)
+{
+ int ret;
+
+ assert(dnsserver_location != NULL);
+ assert(path != NULL);
+
+ unix_socket_loc = safestrdup(path);
+
+ if ((dnsserver_process = fork()) == 0) {
+ /* Child process */
+ chdir("/");
+ umask(077);
+
+ close(0);
+ close(1);
+ close(2);
+
+ /* Start the "dnsserver" program */
+ ret = execl(dnsserver_location,
+ dnsserver_location,
+ path,
+ NULL);
+
+ if (ret < 0)
+ return -ENOEXEC;
+ }
+
+ /* Parent process */
+ return 0;
+}
+
+/*
+ * Stop the dnsserver process.
+ */
+int
+stop_dnsserver(void)
+{
+ kill(dnsserver_process, SIGTERM);
+ kill(dnsserver_process, SIGKILL);
+ unlink(unix_socket_loc);
+
+ return 0;
+}
+
+/*
+ * Returns a socket connected to the "dnsserver"
+ */
+int
+dns_connect(void)
+{
+ int dns;
+ struct sockaddr_un addr;
+
+ dns = socket(AF_LOCAL, SOCK_STREAM, 0);
+ if (dns < 0)
+ return -EIO;
+
+ memset(&addr, 0, sizeof(addr));
+ addr.sun_family = AF_LOCAL;
+ strcpy(addr.sun_path, unix_socket_loc);
+
+ if (connect(dns, (struct sockaddr *)&addr, sizeof(addr)) < 0)
+ return -EIO;
+ else
+ return dns;
+}
+
+/*
+ * Closes the connection to the "dnsserver"
+ */
+void
+dns_disconnect(int dns)
+{
+ assert(dns >= 0);
+
+ safe_write(dns, "$shutdown\n", 10);
+ close(dns);
+}
+
+/*
+ * Takes a dotted-decimal IP address and returns the host name in the
+ * buffer supplied by the caller.
+ *
+ * Returns: 0 if the buffer is filled correctly, or
+ * -1 if there was an error
+ */
+int
+dns_gethostbyaddr(int dns, const char* ipaddr, char** hostname,
+ size_t hostlen)
+{
+ char* buffer;
+ ssize_t len;
+ char *ptr;
+
+ assert(dns >= 0);
+ assert(ipaddr != NULL);
+ assert(hostname != NULL);
+ assert(hostlen > 0);
+
+ write_message(dns, "%s\n", ipaddr);
+ len = readline(dns, &buffer);
+ if (len < 0)
+ return len;
+ chomp(buffer, len);
+
+ if (strncmp(buffer, "$fail", 5) == 0) {
+ /* There was a problem. */
+ safefree(buffer);
+ return -ENOMSG;
+ }
+
+ ptr = strchr(buffer, ' ');
+ ptr++;
+
+ strlcpy(*hostname, ptr, hostlen);
+
+ safefree(buffer);
+ return 0;
+}
+
+/*
+ * Takes a host name and returns an array of IP addresses. The caller
+ * is responsible for freeing the 'addresses' memory block.
+ */
+int
+dns_getaddrbyname(int dns, const char* name, struct in_addr** addresses)
+{
+ char* buffer;
+ ssize_t len;
+ char *ptr;
+
+ assert(dns >= 0);
+ assert(name != NULL);
+ assert(addresses != NULL);
+
+ write_message(dns, "%s\n", name);
+ len = readline(dns, &buffer);
+ if (len < 0)
+ return len;
+ chomp(buffer, len);
+
+ if (strncmp(buffer, "$fail", 5) == 0) {
+ safefree(buffer);
+ return -ENOMSG;
+ }
+
+ ptr = strchr(buffer + 6, ' ');
+ if (ptr)
+ *ptr = '\0';
+
+ *addresses = safemalloc(sizeof(struct in_addr));
+ if (!*addresses) {
+ safefree(buffer);
+ return -ENOMEM;
+ }
+
+ inet_aton(buffer + 6, *addresses);
+
+ safefree(buffer);
+ return 0;
+}