1 /*
2  * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without modification,
6  * are permitted provided that the following conditions are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright notice,
9  *    this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright notice,
11  *    this list of conditions and the following disclaimer in the documentation
12  *    and/or other materials provided with the distribution.
13  * 3. The name of the author may not be used to endorse or promote products
14  *    derived from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
17  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
18  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
19  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
20  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
21  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
22  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
23  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
24  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
25  * OF SUCH DAMAGE.
26  *
27  * This file is part of the lwIP TCP/IP stack.
28  *
29  * Author: Adam Dunkels <adam@sics.se>
30  *
31  */
32 #ifndef __LWIP_IP_H__
33 #define __LWIP_IP_H__
34 
35 #include "lwip/opt.h"
36 
37 #include "lwip/def.h"
38 #include "lwip/pbuf.h"
39 #include "lwip/ip_addr.h"
40 #include "lwip/err.h"
41 #include "lwip/netif.h"
42 
43 #ifdef __cplusplus
44 extern "C" {
45 #endif
46 
47 /** Currently, the function ip_output_if_opt() is only used with IGMP */
48 #define IP_OPTIONS_SEND   LWIP_IGMP
49 
50 #define IP_HLEN 20
51 
52 #define IP_PROTO_ICMP    1
53 #define IP_PROTO_UDP     17
54 #define IP_PROTO_UDPLITE 136
55 #define IP_PROTO_TCP     6
56 
57 /* This is passed as the destination address to ip_output_if (not
58    to ip_output), meaning that an IP header already is constructed
59    in the pbuf. This is used when TCP retransmits. */
60 #ifdef IP_HDRINCL
61 #undef IP_HDRINCL
62 #endif /* IP_HDRINCL */
63 #define IP_HDRINCL  NULL
64 
65 #if LWIP_NETIF_HWADDRHINT
66 #define IP_PCB_ADDRHINT ;u8_t addr_hint
67 #else
68 #define IP_PCB_ADDRHINT
69 #endif /* LWIP_NETIF_HWADDRHINT */
70 
71 /* This is the common part of all PCB types. It needs to be at the
72    beginning of a PCB type definition. It is located here so that
73    changes to this common part are made in one location instead of
74    having to change all PCB structs. */
75 #define IP_PCB \
76   /* ip addresses in network byte order */ \
77   struct ip_addr local_ip; \
78   struct ip_addr remote_ip; \
79    /* Socket options */  \
80   u16_t so_options;      \
81    /* Type Of Service */ \
82   u8_t tos;              \
83   /* Time To Live */     \
84   u8_t ttl               \
85   /* link layer address resolution hint */ \
86   IP_PCB_ADDRHINT
87 
88 struct ip_pcb {
89 /* Common members of all PCB types */
90   IP_PCB;
91 };
92 
93 /*
94  * Option flags per-socket. These are the same like SO_XXX.
95  */
96 #define SOF_DEBUG       (u16_t)0x0001U    /* turn on debugging info recording */
97 #define SOF_ACCEPTCONN  (u16_t)0x0002U    /* socket has had listen() */
98 #define SOF_REUSEADDR   (u16_t)0x0004U    /* allow local address reuse */
99 #define SOF_KEEPALIVE   (u16_t)0x0008U    /* keep connections alive */
100 #define SOF_DONTROUTE   (u16_t)0x0010U    /* just use interface addresses */
101 #define SOF_BROADCAST   (u16_t)0x0020U    /* permit to send and to receive broadcast messages (see IP_SOF_BROADCAST option) */
102 #define SOF_USELOOPBACK (u16_t)0x0040U    /* bypass hardware when possible */
103 #define SOF_LINGER      (u16_t)0x0080U    /* linger on close if data present */
104 #define SOF_OOBINLINE   (u16_t)0x0100U    /* leave received OOB data in line */
105 #define SOF_REUSEPORT   (u16_t)0x0200U    /* allow local address & port reuse */
106 
107 
108 #ifdef PACK_STRUCT_USE_INCLUDES
109 #  include "arch/bpstruct.h"
110 #endif
111 PACK_STRUCT_BEGIN
112 struct ip_hdr {
113   /* version / header length / type of service */
114   PACK_STRUCT_FIELD(u16_t _v_hl_tos);
115   /* total length */
116   PACK_STRUCT_FIELD(u16_t _len);
117   /* identification */
118   PACK_STRUCT_FIELD(u16_t _id);
119   /* fragment offset field */
120   PACK_STRUCT_FIELD(u16_t _offset);
121 #define IP_RF 0x8000        /* reserved fragment flag */
122 #define IP_DF 0x4000        /* dont fragment flag */
123 #define IP_MF 0x2000        /* more fragments flag */
124 #define IP_OFFMASK 0x1fff   /* mask for fragmenting bits */
125   /* time to live / protocol*/
126   PACK_STRUCT_FIELD(u16_t _ttl_proto);
127   /* checksum */
128   PACK_STRUCT_FIELD(u16_t _chksum);
129   /* source and destination IP addresses */
130   PACK_STRUCT_FIELD(struct ip_addr src);
131   PACK_STRUCT_FIELD(struct ip_addr dest);
132 } PACK_STRUCT_STRUCT;
133 PACK_STRUCT_END
134 #ifdef PACK_STRUCT_USE_INCLUDES
135 #  include "arch/epstruct.h"
136 #endif
137 
138 #define IPH_V(hdr)  (ntohs((hdr)->_v_hl_tos) >> 12)
139 #define IPH_HL(hdr) ((ntohs((hdr)->_v_hl_tos) >> 8) & 0x0f)
140 #define IPH_TOS(hdr) (ntohs((hdr)->_v_hl_tos) & 0xff)
141 #define IPH_LEN(hdr) ((hdr)->_len)
142 #define IPH_ID(hdr) ((hdr)->_id)
143 #define IPH_OFFSET(hdr) ((hdr)->_offset)
144 #define IPH_TTL(hdr) (ntohs((hdr)->_ttl_proto) >> 8)
145 #define IPH_PROTO(hdr) (ntohs((hdr)->_ttl_proto) & 0xff)
146 #define IPH_CHKSUM(hdr) ((hdr)->_chksum)
147 
148 #define IPH_VHLTOS_SET(hdr, v, hl, tos) (hdr)->_v_hl_tos = (htons(((v) << 12) | ((hl) << 8) | (tos)))
149 #define IPH_LEN_SET(hdr, len) (hdr)->_len = (len)
150 #define IPH_ID_SET(hdr, id) (hdr)->_id = (id)
151 #define IPH_OFFSET_SET(hdr, off) (hdr)->_offset = (off)
152 #define IPH_TTL_SET(hdr, ttl) (hdr)->_ttl_proto = (htons(IPH_PROTO(hdr) | ((u16_t)(ttl) << 8)))
153 #define IPH_PROTO_SET(hdr, proto) (hdr)->_ttl_proto = (htons((proto) | (IPH_TTL(hdr) << 8)))
154 #define IPH_CHKSUM_SET(hdr, chksum) (hdr)->_chksum = (chksum)
155 
156 #define ip_init() /* Compatibility define, not init needed. */
157 struct netif *ip_route(struct ip_addr *dest);
158 err_t ip_input(struct pbuf *p, struct netif *inp);
159 err_t ip_output(struct pbuf *p, struct ip_addr *src, struct ip_addr *dest,
160        u8_t ttl, u8_t tos, u8_t proto);
161 err_t ip_output_if(struct pbuf *p, struct ip_addr *src, struct ip_addr *dest,
162        u8_t ttl, u8_t tos, u8_t proto,
163        struct netif *netif);
164 #if LWIP_NETIF_HWADDRHINT
165 err_t ip_output_hinted(struct pbuf *p, struct ip_addr *src, struct ip_addr *dest,
166        u8_t ttl, u8_t tos, u8_t proto, u8_t *addr_hint);
167 #endif /* LWIP_NETIF_HWADDRHINT */
168 #if IP_OPTIONS_SEND
169 err_t ip_output_if_opt(struct pbuf *p, struct ip_addr *src, struct ip_addr *dest,
170        u8_t ttl, u8_t tos, u8_t proto, struct netif *netif, void *ip_options,
171        u16_t optlen);
172 #endif /* IP_OPTIONS_SEND */
173 struct netif *ip_current_netif(void);
174 const struct ip_hdr *ip_current_header(void);
175 #if IP_DEBUG
176 void ip_debug_print(struct pbuf *p);
177 #else
178 #define ip_debug_print(p)
179 #endif /* IP_DEBUG */
180 
181 #ifdef __cplusplus
182 }
183 #endif
184 
185 #endif /* __LWIP_IP_H__ */
186 
187 
188