/src/systemd/src/libsystemd-network/dhcp-network.c

Source (jump to first uncovered line)
/* SPDX-License-Identifier: LGPL-2.1-or-later */
/***
  Copyright © 2013 Intel Corporation. All rights reserved.
***/

#include <linux/filter.h>
#include <linux/if_infiniband.h>
#include <linux/if_packet.h>
#include <net/if_arp.h>
#include <stdio.h>
#include <string.h>

#include "dhcp-network.h"
#include "dhcp-protocol.h"
#include "ether-addr-util.h"
#include "fd-util.h"
#include "socket-util.h"
#include "unaligned.h"

static int _bind_raw_socket(
                int ifindex,
                union sockaddr_union *link,
                uint32_t xid,
                const struct hw_addr_data *hw_addr,
                const struct hw_addr_data *bcast_addr,
                uint16_t arp_type,
                uint16_t port,
                bool so_priority_set,
                int so_priority) {

        assert(ifindex > 0);
        assert(link);
        assert(hw_addr);
        assert(bcast_addr);
        assert(IN_SET(arp_type, ARPHRD_ETHER, ARPHRD_INFINIBAND));

        switch (arp_type) {
        case ARPHRD_ETHER:
                assert(hw_addr->length == ETH_ALEN);
                assert(bcast_addr->length == ETH_ALEN);
                break;
        case ARPHRD_INFINIBAND:
                assert(hw_addr->length == 0);
                assert(bcast_addr->length == INFINIBAND_ALEN);
                break;
        default:
                assert_not_reached();
        }

        struct sock_filter filter[] = {
                BPF_STMT(BPF_LD + BPF_W + BPF_LEN, 0),                                 /* A <- packet length */
                BPF_JUMP(BPF_JMP + BPF_JGE + BPF_K, sizeof(DHCPPacket), 1, 0),         /* packet >= DHCPPacket ? */
                BPF_STMT(BPF_RET + BPF_K, 0),                                          /* ignore */
                BPF_STMT(BPF_LD + BPF_B + BPF_ABS, offsetof(DHCPPacket, ip.protocol)), /* A <- IP protocol */
                BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, IPPROTO_UDP, 1, 0),                /* IP protocol == UDP ? */
                BPF_STMT(BPF_RET + BPF_K, 0),                                          /* ignore */
                BPF_STMT(BPF_LD + BPF_B + BPF_ABS, offsetof(DHCPPacket, ip.frag_off)), /* A <- Flags */
                BPF_STMT(BPF_ALU + BPF_AND + BPF_K, 0x20),                             /* A <- A & 0x20 (More Fragments bit) */
                BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, 0, 1, 0),                          /* A == 0 ? */
                BPF_STMT(BPF_RET + BPF_K, 0),                                          /* ignore */
                BPF_STMT(BPF_LD + BPF_H + BPF_ABS, offsetof(DHCPPacket, ip.frag_off)), /* A <- Flags + Fragment offset */
                BPF_STMT(BPF_ALU + BPF_AND + BPF_K, 0x1fff),                           /* A <- A & 0x1fff (Fragment offset) */
                BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, 0, 1, 0),                          /* A == 0 ? */
                BPF_STMT(BPF_RET + BPF_K, 0),                                          /* ignore */
                BPF_STMT(BPF_LD + BPF_H + BPF_ABS, offsetof(DHCPPacket, udp.dest)),    /* A <- UDP destination port */
                BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, port, 1, 0),                       /* UDP destination port == DHCP client port ? */
                BPF_STMT(BPF_RET + BPF_K, 0),                                          /* ignore */
                BPF_STMT(BPF_LD + BPF_B + BPF_ABS, offsetof(DHCPPacket, dhcp.op)),     /* A <- DHCP op */
                BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, BOOTREPLY, 1, 0),                  /* op == BOOTREPLY ? */
                BPF_STMT(BPF_RET + BPF_K, 0),                                          /* ignore */
                BPF_STMT(BPF_LD + BPF_B + BPF_ABS, offsetof(DHCPPacket, dhcp.htype)),  /* A <- DHCP header type */
                BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, arp_type, 1, 0),                   /* header type == arp_type ? */
                BPF_STMT(BPF_RET + BPF_K, 0),                                          /* ignore */
                BPF_STMT(BPF_LD + BPF_W + BPF_ABS, offsetof(DHCPPacket, dhcp.xid)),    /* A <- client identifier */
                BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, xid, 1, 0),                        /* client identifier == xid ? */
                BPF_STMT(BPF_RET + BPF_K, 0),                                          /* ignore */
                BPF_STMT(BPF_LD + BPF_B + BPF_ABS, offsetof(DHCPPacket, dhcp.hlen)),   /* A <- MAC address length */
                BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, (uint8_t) hw_addr->length, 1, 0),  /* address length == hw_addr->length ? */
                BPF_STMT(BPF_RET + BPF_K, 0),                                          /* ignore */

                /* We only support MAC address length to be either 0 or 6 (ETH_ALEN). Optionally
                 * compare chaddr for ETH_ALEN bytes. */
                BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, ETH_ALEN, 0, 8),                        /* A (the MAC address length) == ETH_ALEN ? */
                BPF_STMT(BPF_LDX + BPF_IMM, unaligned_read_be32(hw_addr->bytes)),           /* X <- 4 bytes of client's MAC */
                BPF_STMT(BPF_LD + BPF_W + BPF_ABS, offsetof(DHCPPacket, dhcp.chaddr)),      /* A <- 4 bytes of MAC from dhcp.chaddr */
                BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_X, 0, 1, 0),                               /* A == X ? */
                BPF_STMT(BPF_RET + BPF_K, 0),                                               /* ignore */
                BPF_STMT(BPF_LDX + BPF_IMM, unaligned_read_be16(hw_addr->bytes + 4)),       /* X <- remainder of client's MAC */
                BPF_STMT(BPF_LD + BPF_H + BPF_ABS, offsetof(DHCPPacket, dhcp.chaddr) + 4),  /* A <- remainder of MAC from dhcp.chaddr */
                BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_X, 0, 1, 0),                               /* A == X ? */
                BPF_STMT(BPF_RET + BPF_K, 0),                                               /* ignore */

                BPF_STMT(BPF_LD + BPF_W + BPF_ABS, offsetof(DHCPPacket, dhcp.magic)),  /* A <- DHCP magic cookie */
                BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, DHCP_MAGIC_COOKIE, 1, 0),          /* cookie == DHCP magic cookie ? */
                BPF_STMT(BPF_RET + BPF_K, 0),                                          /* ignore */
                BPF_STMT(BPF_RET + BPF_K, UINT32_MAX),                                 /* accept */
        };
        struct sock_fprog fprog = {
                .len = ELEMENTSOF(filter),
                .filter = filter
        };
        _cleanup_close_ int s = -EBADF;
        int r;

        s = socket(AF_PACKET, SOCK_DGRAM | SOCK_CLOEXEC | SOCK_NONBLOCK, 0);
        if (s < 0)
                return -errno;

        r = setsockopt_int(s, SOL_PACKET, PACKET_AUXDATA, true);
        if (r < 0)
                return r;

        r = setsockopt(s, SOL_SOCKET, SO_ATTACH_FILTER, &fprog, sizeof(fprog));
        if (r < 0)
                return -errno;

        r = setsockopt_int(s, SOL_SOCKET, SO_TIMESTAMP, true);
        if (r < 0)
                return r;

        if (so_priority_set) {
                r = setsockopt_int(s, SOL_SOCKET, SO_PRIORITY, so_priority);
                if (r < 0)
                        return r;
        }

        link->ll = (struct sockaddr_ll) {
                .sll_family = AF_PACKET,
                .sll_protocol = htobe16(ETH_P_IP),
                .sll_ifindex = ifindex,
                .sll_hatype = htobe16(arp_type),
                .sll_halen = bcast_addr->length,
        };
        /* We may overflow link->ll. link->ll_buffer ensures we have enough space. */
        memcpy(link->ll.sll_addr, bcast_addr->bytes, bcast_addr->length);

        r = bind(s, &link->sa, sockaddr_ll_len(&link->ll));
        if (r < 0)
                return -errno;

        return TAKE_FD(s);
}

int dhcp_network_bind_raw_socket(
                int ifindex,
                union sockaddr_union *link,
                uint32_t xid,
                const struct hw_addr_data *hw_addr,
                const struct hw_addr_data *bcast_addr,
                uint16_t arp_type,
                uint16_t port,
                bool so_priority_set,
                int so_priority) {

        static struct hw_addr_data default_eth_bcast = {
                .length = ETH_ALEN,
                .ether = {{ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }},
        }, default_ib_bcast = {
                .length = INFINIBAND_ALEN,
                .infiniband = {
                        0x00, 0xff, 0xff, 0xff, 0xff, 0x12, 0x40, 0x1b,
                        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
                        0xff, 0xff, 0xff, 0xff
                },
        };

        assert(ifindex > 0);
        assert(link);
        assert(hw_addr);

        switch (arp_type) {
        case ARPHRD_ETHER:
                return _bind_raw_socket(ifindex, link, xid,
                                        hw_addr,
                                        (bcast_addr && !hw_addr_is_null(bcast_addr)) ? bcast_addr : &default_eth_bcast,
                                        arp_type, port, so_priority_set, so_priority);

        case ARPHRD_INFINIBAND:
                return _bind_raw_socket(ifindex, link, xid,
                                        &HW_ADDR_NULL,
                                        (bcast_addr && !hw_addr_is_null(bcast_addr)) ? bcast_addr : &default_ib_bcast,
                                        arp_type, port, so_priority_set, so_priority);
        default:
                return -EINVAL;
        }
}

int dhcp_network_bind_udp_socket(int ifindex, be32_t address, uint16_t port, int ip_service_type) {
        union sockaddr_union src = {
                .in.sin_family = AF_INET,
                .in.sin_port = htobe16(port),
                .in.sin_addr.s_addr = address,
        };
        _cleanup_close_ int s = -EBADF;
        int r;

        s = socket(AF_INET, SOCK_DGRAM | SOCK_CLOEXEC | SOCK_NONBLOCK, 0);
        if (s < 0)
                return -errno;

        if (ip_service_type >= 0)
                r = setsockopt_int(s, IPPROTO_IP, IP_TOS, ip_service_type);
        else
                r = setsockopt_int(s, IPPROTO_IP, IP_TOS, IPTOS_CLASS_CS6);
        if (r < 0)
                return r;

        r = setsockopt_int(s, SOL_SOCKET, SO_REUSEADDR, true);
        if (r < 0)
                return r;

        r = setsockopt_int(s, SOL_SOCKET, SO_TIMESTAMP, true);
        if (r < 0)
                return r;

        if (ifindex > 0) {
                r = socket_bind_to_ifindex(s, ifindex);
                if (r < 0)
                        return r;
        }

        if (port == DHCP_PORT_SERVER) {
                r = setsockopt_int(s, SOL_SOCKET, SO_BROADCAST, true);
                if (r < 0)
                        return r;
                if (address == INADDR_ANY) {
                        /* IP_PKTINFO filter should not be applied when packets are
                           allowed to enter/leave through the interface other than
                           DHCP server sits on(BindToInterface option). */
                        r = setsockopt_int(s, IPPROTO_IP, IP_PKTINFO, true);
                        if (r < 0)
                                return r;
                }
        } else {
                r = setsockopt_int(s, IPPROTO_IP, IP_FREEBIND, true);
                if (r < 0)
                        return r;
        }

        if (bind(s, &src.sa, sizeof(src.in)) < 0)
                return -errno;

        return TAKE_FD(s);
}

int dhcp_network_send_raw_socket(
                int s,
                const union sockaddr_union *link,
                const void *packet,
                size_t len) {

        /* Do not add assert(s >= 0) here, as this is called in fuzz-dhcp-server, and in that case this
         * function should fail with negative errno. */

        assert(link);
        assert(packet);
        assert(len > 0);

        if (sendto(s, packet, len, 0, &link->sa, sockaddr_ll_len(&link->ll)) < 0)
                return -errno;

        return 0;
}

int dhcp_network_send_udp_socket(
                int s,
                be32_t address,
                uint16_t port,
                const void *packet,
                size_t len) {

        union sockaddr_union dest = {
                .in.sin_family = AF_INET,
                .in.sin_port = htobe16(port),
                .in.sin_addr.s_addr = address,
        };

        assert(s >= 0);
        assert(packet);
        assert(len > 0);

        if (sendto(s, packet, len, 0, &dest.sa, sizeof(dest.in)) < 0)
                return -errno;

        return 0;
}

Coverage Report

Created: 2025-06-13 06:25

Line	Count	Source (jump to first uncovered line)
1		/* SPDX-License-Identifier: LGPL-2.1-or-later */
2		/***
3		Copyright © 2013 Intel Corporation. All rights reserved.
4		***/
5
6		#include <linux/filter.h>
7		#include <linux/if_infiniband.h>
8		#include <linux/if_packet.h>
9		#include <net/if_arp.h>
10		#include <stdio.h>
11		#include <string.h>
12
13		#include "dhcp-network.h"
14		#include "dhcp-protocol.h"
15		#include "ether-addr-util.h"
16		#include "fd-util.h"
17		#include "socket-util.h"
18		#include "unaligned.h"
19
20		static int _bind_raw_socket(
21		int ifindex,
22		union sockaddr_union *link,
23		uint32_t xid,
24		const struct hw_addr_data *hw_addr,
25		const struct hw_addr_data *bcast_addr,
26		uint16_t arp_type,
27		uint16_t port,
28		bool so_priority_set,
29	0	int so_priority) {
30
31	0	assert(ifindex > 0);
32	0	assert(link);
33	0	assert(hw_addr);
34	0	assert(bcast_addr);
35	0	assert(IN_SET(arp_type, ARPHRD_ETHER, ARPHRD_INFINIBAND));
36
37	0	switch (arp_type) {
38	0	case ARPHRD_ETHER:
39	0	assert(hw_addr->length == ETH_ALEN);
40	0	assert(bcast_addr->length == ETH_ALEN);
41	0	break;
42	0	case ARPHRD_INFINIBAND:
43	0	assert(hw_addr->length == 0);
44	0	assert(bcast_addr->length == INFINIBAND_ALEN);
45	0	break;
46	0	default:
47	0	assert_not_reached();
48	0	}
49
50	0	struct sock_filter filter[] = {
51	0	BPF_STMT(BPF_LD + BPF_W + BPF_LEN, 0), /* A <- packet length */
52	0	BPF_JUMP(BPF_JMP + BPF_JGE + BPF_K, sizeof(DHCPPacket), 1, 0), /* packet >= DHCPPacket ? */
53	0	BPF_STMT(BPF_RET + BPF_K, 0), /* ignore */
54	0	BPF_STMT(BPF_LD + BPF_B + BPF_ABS, offsetof(DHCPPacket, ip.protocol)), /* A <- IP protocol */
55	0	BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, IPPROTO_UDP, 1, 0), /* IP protocol == UDP ? */
56	0	BPF_STMT(BPF_RET + BPF_K, 0), /* ignore */
57	0	BPF_STMT(BPF_LD + BPF_B + BPF_ABS, offsetof(DHCPPacket, ip.frag_off)), /* A <- Flags */
58	0	BPF_STMT(BPF_ALU + BPF_AND + BPF_K, 0x20), /* A <- A & 0x20 (More Fragments bit) */
59	0	BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, 0, 1, 0), /* A == 0 ? */
60	0	BPF_STMT(BPF_RET + BPF_K, 0), /* ignore */
61	0	BPF_STMT(BPF_LD + BPF_H + BPF_ABS, offsetof(DHCPPacket, ip.frag_off)), /* A <- Flags + Fragment offset */
62	0	BPF_STMT(BPF_ALU + BPF_AND + BPF_K, 0x1fff), /* A <- A & 0x1fff (Fragment offset) */
63	0	BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, 0, 1, 0), /* A == 0 ? */
64	0	BPF_STMT(BPF_RET + BPF_K, 0), /* ignore */
65	0	BPF_STMT(BPF_LD + BPF_H + BPF_ABS, offsetof(DHCPPacket, udp.dest)), /* A <- UDP destination port */
66	0	BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, port, 1, 0), /* UDP destination port == DHCP client port ? */
67	0	BPF_STMT(BPF_RET + BPF_K, 0), /* ignore */
68	0	BPF_STMT(BPF_LD + BPF_B + BPF_ABS, offsetof(DHCPPacket, dhcp.op)), /* A <- DHCP op */
69	0	BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, BOOTREPLY, 1, 0), /* op == BOOTREPLY ? */
70	0	BPF_STMT(BPF_RET + BPF_K, 0), /* ignore */
71	0	BPF_STMT(BPF_LD + BPF_B + BPF_ABS, offsetof(DHCPPacket, dhcp.htype)), /* A <- DHCP header type */
72	0	BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, arp_type, 1, 0), /* header type == arp_type ? */
73	0	BPF_STMT(BPF_RET + BPF_K, 0), /* ignore */
74	0	BPF_STMT(BPF_LD + BPF_W + BPF_ABS, offsetof(DHCPPacket, dhcp.xid)), /* A <- client identifier */
75	0	BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, xid, 1, 0), /* client identifier == xid ? */
76	0	BPF_STMT(BPF_RET + BPF_K, 0), /* ignore */
77	0	BPF_STMT(BPF_LD + BPF_B + BPF_ABS, offsetof(DHCPPacket, dhcp.hlen)), /* A <- MAC address length */
78	0	BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, (uint8_t) hw_addr->length, 1, 0), /* address length == hw_addr->length ? */
79	0	BPF_STMT(BPF_RET + BPF_K, 0), /* ignore */
80
81		/* We only support MAC address length to be either 0 or 6 (ETH_ALEN). Optionally
82		* compare chaddr for ETH_ALEN bytes. */
83	0	BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, ETH_ALEN, 0, 8), /* A (the MAC address length) == ETH_ALEN ? */
84	0	BPF_STMT(BPF_LDX + BPF_IMM, unaligned_read_be32(hw_addr->bytes)), /* X <- 4 bytes of client's MAC */
85	0	BPF_STMT(BPF_LD + BPF_W + BPF_ABS, offsetof(DHCPPacket, dhcp.chaddr)), /* A <- 4 bytes of MAC from dhcp.chaddr */
86	0	BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_X, 0, 1, 0), /* A == X ? */
87	0	BPF_STMT(BPF_RET + BPF_K, 0), /* ignore */
88	0	BPF_STMT(BPF_LDX + BPF_IMM, unaligned_read_be16(hw_addr->bytes + 4)), /* X <- remainder of client's MAC */
89	0	BPF_STMT(BPF_LD + BPF_H + BPF_ABS, offsetof(DHCPPacket, dhcp.chaddr) + 4), /* A <- remainder of MAC from dhcp.chaddr */
90	0	BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_X, 0, 1, 0), /* A == X ? */
91	0	BPF_STMT(BPF_RET + BPF_K, 0), /* ignore */
92
93	0	BPF_STMT(BPF_LD + BPF_W + BPF_ABS, offsetof(DHCPPacket, dhcp.magic)), /* A <- DHCP magic cookie */
94	0	BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, DHCP_MAGIC_COOKIE, 1, 0), /* cookie == DHCP magic cookie ? */
95	0	BPF_STMT(BPF_RET + BPF_K, 0), /* ignore */
96	0	BPF_STMT(BPF_RET + BPF_K, UINT32_MAX), /* accept */
97	0	};
98	0	struct sock_fprog fprog = {
99	0	.len = ELEMENTSOF(filter),
100	0	.filter = filter
101	0	};
102	0	_cleanup_close_ int s = -EBADF;
103	0	int r;
104
105	0	s = socket(AF_PACKET, SOCK_DGRAM \| SOCK_CLOEXEC \| SOCK_NONBLOCK, 0);
106	0	if (s < 0)
107	0	return -errno;
108
109	0	r = setsockopt_int(s, SOL_PACKET, PACKET_AUXDATA, true);
110	0	if (r < 0)
111	0	return r;
112
113	0	r = setsockopt(s, SOL_SOCKET, SO_ATTACH_FILTER, &fprog, sizeof(fprog));
114	0	if (r < 0)
115	0	return -errno;
116
117	0	r = setsockopt_int(s, SOL_SOCKET, SO_TIMESTAMP, true);
118	0	if (r < 0)
119	0	return r;
120
121	0	if (so_priority_set) {
122	0	r = setsockopt_int(s, SOL_SOCKET, SO_PRIORITY, so_priority);
123	0	if (r < 0)
124	0	return r;
125	0	}
126
127	0	link->ll = (struct sockaddr_ll) {
128	0	.sll_family = AF_PACKET,
129	0	.sll_protocol = htobe16(ETH_P_IP),
130	0	.sll_ifindex = ifindex,
131	0	.sll_hatype = htobe16(arp_type),
132	0	.sll_halen = bcast_addr->length,
133	0	};
134		/* We may overflow link->ll. link->ll_buffer ensures we have enough space. */
135	0	memcpy(link->ll.sll_addr, bcast_addr->bytes, bcast_addr->length);
136
137	0	r = bind(s, &link->sa, sockaddr_ll_len(&link->ll));
138	0	if (r < 0)
139	0	return -errno;
140
141	0	return TAKE_FD(s);
142	0	}
143
144		int dhcp_network_bind_raw_socket(
145		int ifindex,
146		union sockaddr_union *link,
147		uint32_t xid,
148		const struct hw_addr_data *hw_addr,
149		const struct hw_addr_data *bcast_addr,
150		uint16_t arp_type,
151		uint16_t port,
152		bool so_priority_set,
153	0	int so_priority) {
154
155	0	static struct hw_addr_data default_eth_bcast = {
156	0	.length = ETH_ALEN,
157	0	.ether = {{ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }},
158	0	}, default_ib_bcast = {
159	0	.length = INFINIBAND_ALEN,
160	0	.infiniband = {
161	0	0x00, 0xff, 0xff, 0xff, 0xff, 0x12, 0x40, 0x1b,
162	0	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
163	0	0xff, 0xff, 0xff, 0xff
164	0	},
165	0	};
166
167	0	assert(ifindex > 0);
168	0	assert(link);
169	0	assert(hw_addr);
170
171	0	switch (arp_type) {
172	0	case ARPHRD_ETHER:
173	0	return _bind_raw_socket(ifindex, link, xid,
174	0	hw_addr,
175	0	(bcast_addr && !hw_addr_is_null(bcast_addr)) ? bcast_addr : &default_eth_bcast,
176	0	arp_type, port, so_priority_set, so_priority);
177
178	0	case ARPHRD_INFINIBAND:
179	0	return _bind_raw_socket(ifindex, link, xid,
180	0	&HW_ADDR_NULL,
181	0	(bcast_addr && !hw_addr_is_null(bcast_addr)) ? bcast_addr : &default_ib_bcast,
182	0	arp_type, port, so_priority_set, so_priority);
183	0	default:
184	0	return -EINVAL;
185	0	}
186	0	}
187
188	0	int dhcp_network_bind_udp_socket(int ifindex, be32_t address, uint16_t port, int ip_service_type) {
189	0	union sockaddr_union src = {
190	0	.in.sin_family = AF_INET,
191	0	.in.sin_port = htobe16(port),
192	0	.in.sin_addr.s_addr = address,
193	0	};
194	0	_cleanup_close_ int s = -EBADF;
195	0	int r;
196
197	0	s = socket(AF_INET, SOCK_DGRAM \| SOCK_CLOEXEC \| SOCK_NONBLOCK, 0);
198	0	if (s < 0)
199	0	return -errno;
200
201	0	if (ip_service_type >= 0)
202	0	r = setsockopt_int(s, IPPROTO_IP, IP_TOS, ip_service_type);
203	0	else
204	0	r = setsockopt_int(s, IPPROTO_IP, IP_TOS, IPTOS_CLASS_CS6);
205	0	if (r < 0)
206	0	return r;
207
208	0	r = setsockopt_int(s, SOL_SOCKET, SO_REUSEADDR, true);
209	0	if (r < 0)
210	0	return r;
211
212	0	r = setsockopt_int(s, SOL_SOCKET, SO_TIMESTAMP, true);
213	0	if (r < 0)
214	0	return r;
215
216	0	if (ifindex > 0) {
217	0	r = socket_bind_to_ifindex(s, ifindex);
218	0	if (r < 0)
219	0	return r;
220	0	}
221
222	0	if (port == DHCP_PORT_SERVER) {
223	0	r = setsockopt_int(s, SOL_SOCKET, SO_BROADCAST, true);
224	0	if (r < 0)
225	0	return r;
226	0	if (address == INADDR_ANY) {
227		/* IP_PKTINFO filter should not be applied when packets are
228		allowed to enter/leave through the interface other than
229		DHCP server sits on(BindToInterface option). */
230	0	r = setsockopt_int(s, IPPROTO_IP, IP_PKTINFO, true);
231	0	if (r < 0)
232	0	return r;
233	0	}
234	0	} else {
235	0	r = setsockopt_int(s, IPPROTO_IP, IP_FREEBIND, true);
236	0	if (r < 0)
237	0	return r;
238	0	}
239
240	0	if (bind(s, &src.sa, sizeof(src.in)) < 0)
241	0	return -errno;
242
243	0	return TAKE_FD(s);
244	0	}
245
246		int dhcp_network_send_raw_socket(
247		int s,
248		const union sockaddr_union *link,
249		const void *packet,
250	193	size_t len) {
251
252		/* Do not add assert(s >= 0) here, as this is called in fuzz-dhcp-server, and in that case this
253		* function should fail with negative errno. */
254
255	193	assert(link);
256	193	assert(packet);
257	193	assert(len > 0);
258
259	193	if (sendto(s, packet, len, 0, &link->sa, sockaddr_ll_len(&link->ll)) < 0)
260	0	return -errno;
261
262	193	return 0;
263	193	}
264
265		int dhcp_network_send_udp_socket(
266		int s,
267		be32_t address,
268		uint16_t port,
269		const void *packet,
270	0	size_t len) {
271
272	0	union sockaddr_union dest = {
273	0	.in.sin_family = AF_INET,
274	0	.in.sin_port = htobe16(port),
275	0	.in.sin_addr.s_addr = address,
276	0	};
277
278	0	assert(s >= 0);
279	0	assert(packet);
280	0	assert(len > 0);
281
282	0	if (sendto(s, packet, len, 0, &dest.sa, sizeof(dest.in)) < 0)
283	0	return -errno;
284
285	0	return 0;
286	0	}