npf_mbuf_subr.c revision 1.1 1 /* $NetBSD: npf_mbuf_subr.c,v 1.1 2012/04/14 21:57:29 rmind Exp $ */
2
3 /*
4 * NPF testing - helper routines.
5 *
6 * Public Domain.
7 */
8
9 #include <sys/types.h>
10 #include <sys/kmem.h>
11
12 #include "npf_impl.h"
13 #include "npf_test.h"
14
15 struct mbuf *
16 mbuf_getwithdata(void *data, size_t len)
17 {
18 struct mbuf *m;
19
20 m = kmem_zalloc(sizeof(struct mbuf), KM_SLEEP);
21 assert(m != NULL);
22 m->m_data = data;
23 m->m_len = len;
24 return m;
25 }
26
27 struct mbuf *
28 mbuf_construct_ether(int proto)
29 {
30 struct mbuf *m0, *m1;
31 struct ether_header *ethdr;
32
33 m0 = m_gethdr(M_WAITOK, MT_HEADER);
34 ethdr = mtod(m0, struct ether_header *);
35 ethdr->ether_type = htons(ETHERTYPE_IP);
36 m0->m_len = sizeof(struct ether_header);
37
38 m1 = mbuf_construct(proto);
39 m0->m_next = m1;
40 m1->m_next = NULL;
41 return m0;
42 }
43
44 struct mbuf *
45 mbuf_construct(int proto)
46 {
47 struct mbuf *m;
48 struct ip *iphdr;
49 struct tcphdr *th;
50 int size;
51
52 m = m_gethdr(M_WAITOK, MT_HEADER);
53 iphdr = mtod(m, struct ip *);
54
55 iphdr->ip_v = IPVERSION;
56 iphdr->ip_hl = sizeof(struct ip) >> 2;
57 iphdr->ip_off = 0;
58 iphdr->ip_ttl = 64;
59 iphdr->ip_p = proto;
60
61 size = sizeof(struct ip);
62
63 switch (proto) {
64 case IPPROTO_TCP:
65 th = (void *)(iphdr + 1);
66 th->th_off = sizeof(struct tcphdr) >> 2;
67 size += sizeof(struct tcphdr);
68 break;
69 case IPPROTO_UDP:
70 size += sizeof(struct udphdr);
71 break;
72 case IPPROTO_ICMP:
73 size += offsetof(struct icmp, icmp_data);
74 break;
75 }
76 iphdr->ip_len = htons(size);
77
78 m->m_len = size;
79 m->m_next = NULL;
80 return m;
81 }
82
83 void *
84 mbuf_return_hdrs(struct mbuf *m, bool ether, struct ip **ip)
85 {
86 struct ip *iphdr;
87
88 if (ether) {
89 struct mbuf *mn = m->m_next;
90 iphdr = mtod(mn, struct ip *);
91 } else {
92 iphdr = mtod(m, struct ip *);
93 }
94 *ip = iphdr;
95 return (void *)(iphdr + 1);
96 }
97
98 void
99 mbuf_icmp_append(struct mbuf *m, struct mbuf *m_orig)
100 {
101 struct ip *iphdr = mtod(m, struct ip *);
102 const size_t hlen = iphdr->ip_hl << 2;
103 struct icmp *ic = (struct icmp *)((uint8_t *)iphdr + hlen);
104 const size_t addlen = m_orig->m_len;
105
106 iphdr->ip_len = htons(ntohs(iphdr->ip_len) + addlen);
107 memcpy(&ic->icmp_ip, mtod(m_orig, struct ip *), addlen);
108 m->m_len += addlen;
109 m_freem(m_orig);
110 }
111