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Diffstat (limited to 'usr.sbin/dhcrelay/dhcrelay.c')
-rw-r--r--usr.sbin/dhcrelay/dhcrelay.c147
1 files changed, 143 insertions, 4 deletions
diff --git a/usr.sbin/dhcrelay/dhcrelay.c b/usr.sbin/dhcrelay/dhcrelay.c
index 1f5f872b998..b80a28494b9 100644
--- a/usr.sbin/dhcrelay/dhcrelay.c
+++ b/usr.sbin/dhcrelay/dhcrelay.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: dhcrelay.c,v 1.31 2008/07/09 20:08:13 sobrado Exp $ */
+/* $OpenBSD: dhcrelay.c,v 1.32 2009/09/03 11:56:49 reyk Exp $ */
/*
* Copyright (c) 2004 Henning Brauer <henning@cvs.openbsd.org>
@@ -47,6 +47,9 @@ void relay(struct interface_info *, struct dhcp_packet *, int,
char *print_hw_addr(int, int, unsigned char *);
void got_response(struct protocol *);
+ssize_t relay_agentinfo(struct interface_info *, struct dhcp_packet *,
+ size_t, struct in_addr *, struct in_addr *);
+
time_t cur_time;
int log_perror = 1;
@@ -55,6 +58,8 @@ u_int16_t server_port;
u_int16_t client_port;
int log_priority;
struct interface_info *interfaces = NULL;
+int server_fd;
+int oflag;
struct server_list {
struct server_list *next;
@@ -75,7 +80,7 @@ main(int argc, char *argv[])
openlog(__progname, LOG_NDELAY, DHCPD_LOG_FACILITY);
setlogmask(LOG_UPTO(LOG_INFO));
- while ((ch = getopt(argc, argv, "di:")) != -1) {
+ while ((ch = getopt(argc, argv, "adi:o")) != -1) {
switch (ch) {
case 'd':
no_daemon = 1;
@@ -89,6 +94,11 @@ main(int argc, char *argv[])
strlcpy(interfaces->name, optarg,
sizeof(interfaces->name));
break;
+ case 'o':
+ /* add the relay agent information option */
+ oflag++;
+ break;
+
default:
usage();
/* not reached */
@@ -125,7 +135,8 @@ main(int argc, char *argv[])
argv++;
}
- log_perror = 0;
+ if (!no_daemon)
+ log_perror = 0;
if (interfaces == NULL)
error("no interface given");
@@ -140,6 +151,10 @@ main(int argc, char *argv[])
discover_interfaces(interfaces);
+ /* Enable the relay agent option by default for enc0 */
+ if (interfaces->hw_address.htype == HTYPE_IPSEC_TUNNEL)
+ oflag++;
+
bzero(&laddr, sizeof laddr);
laddr.sin_len = sizeof laddr;
laddr.sin_family = AF_INET;
@@ -165,6 +180,21 @@ main(int argc, char *argv[])
add_protocol("server", sp->fd, got_response, sp);
}
+ /* Socket used to forward packets to the DHCP server */
+ if (interfaces->hw_address.htype == HTYPE_IPSEC_TUNNEL) {
+ laddr.sin_addr.s_addr = INADDR_ANY;
+ server_fd = socket(AF_INET, SOCK_DGRAM, 0);
+ if (server_fd == -1)
+ error("socket: %m");
+ opt = 1;
+ if (setsockopt(server_fd, SOL_SOCKET, SO_REUSEPORT,
+ &opt, sizeof(opt)) == -1)
+ error("setsockopt: %m");
+ if (bind(server_fd, (struct sockaddr *)&laddr,
+ sizeof(laddr)) == -1)
+ error("bind: %m");
+ }
+
tzset();
time(&cur_time);
@@ -222,6 +252,13 @@ relay(struct interface_info *ip, struct dhcp_packet *packet, int length,
memcpy(hto.haddr, packet->chaddr, hto.hlen);
hto.htype = packet->htype;
+ if ((length = relay_agentinfo(interfaces,
+ packet, length, NULL, &to.sin_addr)) == -1) {
+ note("ingnoring BOOTREPLY with invalid "
+ "relay agent information");
+ return;
+ }
+
if (send_packet(interfaces, packet, length,
interfaces->primary_address, &to, &hto) != -1)
debug("forwarded BOOTREPLY for %s to %s",
@@ -248,6 +285,13 @@ relay(struct interface_info *ip, struct dhcp_packet *packet, int length,
correct net. */
packet->giaddr = ip->primary_address;
+ if ((length = relay_agentinfo(ip, packet, length,
+ (struct in_addr *)from.iabuf, NULL)) == -1) {
+ note("ingnoring BOOTREQUEST with invalid "
+ "relay agent information");
+ return;
+ }
+
/* Otherwise, it's a BOOTREQUEST, so forward it to all the
servers. */
for (sp = servers; sp; sp = sp->next) {
@@ -265,7 +309,7 @@ usage(void)
{
extern char *__progname;
- fprintf(stderr, "usage: %s [-d] -i interface server1 [... serverN]\n",
+ fprintf(stderr, "usage: %s [-do] -i interface server1 [... serverN]\n",
__progname);
exit(1);
}
@@ -311,6 +355,7 @@ got_response(struct protocol *l)
} u;
struct server_list *sp = l->local;
+ memset(&u, DHO_END, sizeof(u));
if ((result = recv(l->fd, u.packbuf, sizeof(u), 0)) == -1 &&
errno != ECONNREFUSED) {
/*
@@ -340,3 +385,97 @@ got_response(struct protocol *l)
sp->to.sin_port, ifrom, NULL);
}
}
+
+ssize_t
+relay_agentinfo(struct interface_info *info, struct dhcp_packet *packet,
+ size_t length, struct in_addr *from, struct in_addr *to)
+{
+ u_int8_t *p;
+ u_int i, j, railen;
+ ssize_t optlen, maxlen, grow;
+
+ if (!oflag)
+ return (length);
+
+ /* Buffer length vs. received packet length */
+ maxlen = DHCP_MTU_MAX - DHCP_FIXED_LEN - DHCP_OPTIONS_COOKIE_LEN - 1;
+ optlen = length - DHCP_FIXED_NON_UDP - DHCP_OPTIONS_COOKIE_LEN;
+ if (maxlen < 1 || optlen < 1)
+ return (length);
+
+ if (memcmp(packet->options, DHCP_OPTIONS_COOKIE,
+ DHCP_OPTIONS_COOKIE_LEN) != 0)
+ return (length);
+ p = packet->options + DHCP_OPTIONS_COOKIE_LEN;
+
+ for (i = 0; i < (u_int)optlen && *p != DHO_END;) {
+ if (*p == DHO_PAD)
+ j = 1;
+ else
+ j = p[1] + 2;
+
+ if ((i + j) > (u_int)optlen) {
+ warning("truncated dhcp options");
+ break;
+ }
+
+ /* Revert any other relay agent information */
+ if (*p == DHO_RELAY_AGENT_INFORMATION) {
+ if (to != NULL) {
+ /* Check the relay agent information */
+ railen = 8 + sizeof(struct in_addr);
+ if (j >= railen &&
+ p[1] == (railen - 2) &&
+ p[2] == RAI_CIRCUIT_ID &&
+ p[3] == 2 &&
+ p[4] == (u_int8_t)(info->index << 8) &&
+ p[5] == (info->index & 0xff) &&
+ p[6] == RAI_REMOTE_ID &&
+ p[7] == sizeof(*to))
+ memcpy(to, p + 8, sizeof(*to));
+
+ /* It should be the last option */
+ memset(p, 0, j);
+ *p = DHO_END;
+ } else {
+ /* Discard invalid option from a client */
+ if (!packet->giaddr.s_addr)
+ return (-1);
+ }
+ return (length);
+ }
+
+ p += j;
+ i += j;
+
+ if (from != NULL && (*p == DHO_END || (i >= optlen))) {
+ j = 8 + sizeof(*from);
+ if ((i + j) > (u_int)maxlen) {
+ warning("skipping agent information");
+ break;
+ }
+
+ /* Append the relay agent information if it fits */
+ p[0] = DHO_RELAY_AGENT_INFORMATION;
+ p[1] = j - 2;
+ p[2] = RAI_CIRCUIT_ID;
+ p[3] = 2;
+ p[4] = info->index << 8;
+ p[5] = info->index & 0xff;
+ p[6] = RAI_REMOTE_ID;
+ p[7] = sizeof(*from);
+ memcpy(p + 8, from, sizeof(*from));
+
+ /* Do we need to increase the packet length? */
+ grow = j + 1 - (optlen - i);
+ if (grow > 0)
+ length += grow;
+ p += j;
+
+ *p = DHO_END;
+ break;
+ }
+ }
+
+ return (length);
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-17 07:34:47 +0000