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authorTimothy Pearson <[email protected]>2013-01-27 01:04:16 -0600
committerTimothy Pearson <[email protected]>2013-01-27 01:04:16 -0600
commit5159cd2beb2e87806a5b54e9991b7895285c9d3e (patch)
tree9b70e8be47a390f8f4d56ead812ab0c9dad88709 /tdeio/misc/kpac/kpac_dhcp_helper.c
parentc17cb900dcf52b8bd6dc300d4f103392900ec2b4 (diff)
downloadtdelibs-5159cd2beb2e87806a5b54e9991b7895285c9d3e.tar.gz
tdelibs-5159cd2beb2e87806a5b54e9991b7895285c9d3e.zip
Rename a number of libraries and executables to avoid conflicts with KDE4
Diffstat (limited to 'tdeio/misc/kpac/kpac_dhcp_helper.c')
-rw-r--r--tdeio/misc/kpac/kpac_dhcp_helper.c229
1 files changed, 229 insertions, 0 deletions
diff --git a/tdeio/misc/kpac/kpac_dhcp_helper.c b/tdeio/misc/kpac/kpac_dhcp_helper.c
new file mode 100644
index 000000000..906e89dfa
--- /dev/null
+++ b/tdeio/misc/kpac/kpac_dhcp_helper.c
@@ -0,0 +1,229 @@
+/* This file is part of the KDE Libraries
+ Copyright (c) 2001 Malte Starostik <[email protected]>
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public
+ License version 2 as published by the Free Software Foundation.
+
+ This library 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
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public License
+ along with this library; see the file COPYING.LIB. If not, write to
+ the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ Boston, MA 02110-1301, USA.
+*/
+
+
+#include <config.h>
+#include <sys/types.h>
+#include <grp.h>
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/time.h>
+#include <sys/socket.h>
+#include <time.h>
+#include <netdb.h>
+#include <netinet/in.h>
+
+#include "dhcp.h"
+
+#ifndef INADDR_NONE /* some OSes don't define this */
+#define INADDR_NONE -1
+#endif
+
+int set_gid(gid_t);
+int set_uid(uid_t);
+int get_port(const char *);
+int init_socket(void);
+uint32_t send_request(int);
+void get_reply(int, uint32_t);
+
+int set_gid(gid_t gid)
+{
+#ifdef HAVE_SHORTSETGROUPS
+ short x[2];
+ x[0] = gid;
+ x[1] = 73; /* catch errors */
+ if (setgroups(1, x) == -1)
+ return -1;
+#else
+ if (setgroups(1, &gid) == -1)
+ return -1;
+#endif
+ return setgid(gid); /* _should_ be redundant, but on some systems it isn't */
+}
+
+int set_uid(uid_t uid)
+{
+ return setuid(uid);
+}
+
+/* All functions below do an exit(1) on the slightest error */
+
+/* Returns the UDP port number for the given service name */
+int get_port(const char *service)
+{
+ struct servent *serv = getservbyname(service, "udp");
+ if (serv == NULL)
+ exit(1);
+
+ return serv->s_port;
+}
+
+/* Opens the UDP socket, binds to the bootpc port and drops root privileges */
+int init_socket()
+{
+ struct sockaddr_in addr;
+ struct protoent *proto;
+ int sock;
+ int bcast = 1;
+
+ memset(&addr, 0, sizeof(addr));
+ addr.sin_family = AF_INET;
+ addr.sin_addr.s_addr = INADDR_ANY;
+ addr.sin_port = get_port("bootpc");
+
+ if ((proto = getprotobyname("udp")) == NULL ||
+ (sock = socket(AF_INET, SOCK_DGRAM, proto->p_proto)) == -1)
+ exit(1);
+
+ if (setsockopt(sock, SOL_SOCKET, SO_BROADCAST, &bcast, sizeof(bcast)) == -1 ||
+ setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &bcast, sizeof(bcast)) == -1 ||
+ bind(sock, (struct sockaddr *)&addr, sizeof(addr)) == -1)
+ exit(1);
+
+ if (set_gid(getgid()) != 0 || /* we don't need it anymore */
+ set_uid(getuid()) != 0)
+ exit(1);
+ return sock;
+}
+
+/* Fills the DHCPINFORM request packet, returns the transaction id */
+uint32_t send_request(int sock)
+{
+ char hostname[256];
+ struct hostent *hent;
+ struct sockaddr_in addr;
+ struct dhcp_msg request;
+ uint8_t *offs = request.options;
+
+ hostname[0] = '\0';
+ hostname[255] = '\0';
+ if (gethostname(hostname, 255) == -1 ||
+ strlen(hostname) == 0 ||
+ (hent = gethostbyname(hostname)) == NULL)
+ exit(1);
+
+ memset(&addr, 0, sizeof(addr));
+ addr.sin_family = AF_INET;
+ addr.sin_addr.s_addr = INADDR_NONE;
+ addr.sin_port = get_port("bootps");
+
+ memset(&request, 0, sizeof(request));
+ request.op = DHCP_BOOTREQUEST;
+ srand(time(NULL));
+ request.xid = rand();
+ request.ciaddr = *(uint32_t*)*hent->h_addr_list;
+
+ *offs++ = DHCP_MAGIC1;
+ *offs++ = DHCP_MAGIC2;
+ *offs++ = DHCP_MAGIC3;
+ *offs++ = DHCP_MAGIC4;
+
+ *offs++ = DHCP_OPT_MSGTYPE;
+ *offs++ = 1; /* length */
+ *offs++ = DHCP_INFORM;
+
+ *offs++ = DHCP_OPT_PARAMREQ;
+ *offs++ = 1; /* length */
+ *offs++ = DHCP_OPT_WPAD;
+
+ *offs++ = DHCP_OPT_END;
+
+ if (sendto(sock, &request, sizeof(request), 0,
+ (struct sockaddr *)&addr, sizeof(addr)) != sizeof(request))
+ exit(1);
+
+ return request.xid;
+}
+
+/* Reads the reply from the socket, checks it and outputs the URL to STDOUT */
+void get_reply(int sock, uint32_t xid)
+{
+ struct dhcp_msg reply;
+ int len;
+ char wpad[DHCP_OPT_LEN + 1];
+ uint8_t wpad_len;
+ uint8_t *offs = reply.options;
+ uint8_t *end;
+
+ if ((len = recvfrom(sock, &reply, sizeof(reply), 0, NULL, NULL)) <= 0)
+ exit(1);
+
+ end = (uint8_t *)&reply + len;
+ if (end < offs + 4 ||
+ end > &reply.options[DHCP_OPT_LEN] ||
+ reply.op != DHCP_BOOTREPLY ||
+ reply.xid != xid ||
+ *offs++ != DHCP_MAGIC1 ||
+ *offs++ != DHCP_MAGIC2 ||
+ *offs++ != DHCP_MAGIC3 ||
+ *offs++ != DHCP_MAGIC4)
+ exit(1);
+
+ for ( ; offs < end - 1; offs += *offs+1)
+ {
+ switch (*offs++)
+ {
+ case DHCP_OPT_END:
+ exit(1);
+ case DHCP_OPT_MSGTYPE:
+ if (*offs != 1 || (offs >= end - 1) || *(offs + 1) != DHCP_ACK)
+ exit(1);
+ break;
+ case DHCP_OPT_WPAD:
+ memset(wpad, 0, sizeof(wpad));
+ wpad_len = *offs++;
+ if (offs >= end)
+ exit(1);
+ if (wpad_len > end - offs)
+ wpad_len = end - offs;
+ strncpy(wpad, (char *)offs, wpad_len);
+ wpad[wpad_len] = 0;
+ printf("%s\n", wpad);
+ close(sock);
+ exit(0);
+ }
+ }
+ exit(1);
+}
+
+int main()
+{
+ fd_set rfds;
+ struct timeval tv;
+ int sock;
+ uint32_t xid;
+
+ sock = init_socket();
+ xid = send_request(sock);
+
+ FD_ZERO(&rfds);
+ FD_SET(sock, &rfds);
+ tv.tv_sec = 5;
+ tv.tv_usec = 0;
+ if (select(sock + 1, &rfds, NULL, NULL, &tv) == 1 && FD_ISSET(sock, &rfds))
+ get_reply(sock, xid);
+
+ close(sock);
+ exit(1);
+}
+
+/* vim: ts=4 sw=4 noet
+ */