xref: /netbsd-src/usr.sbin/npf/npftest/libnpftest/npf_nbuf_test.c (revision 946379e7b37692fc43f68eb0d1c10daa0a7f3b6c)
1 /*	$NetBSD: npf_nbuf_test.c,v 1.5 2013/11/08 00:38:27 rmind Exp $	*/
2 
3 /*
4  * NPF nbuf interface test.
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 #define	MBUF_CHAIN_LEN		128
16 
17 CTASSERT((MBUF_CHAIN_LEN % sizeof(uint32_t)) == 0);
18 
19 static void
20 mbuf_consistency_check(nbuf_t *nbuf)
21 {
22 	struct mbuf *m = nbuf_head_mbuf(nbuf);
23 
24 	while (m) {
25 		assert(m->m_type != MT_FREE);
26 		m = m->m_next;
27 	}
28 }
29 
30 static char *
31 parse_nbuf_chain(struct mbuf *m)
32 {
33 	ifnet_t *dummy_ifp = npf_test_addif(IFNAME_TEST, false, false);
34 	char *s = kmem_zalloc(MBUF_CHAIN_LEN + 1, KM_SLEEP);
35 	nbuf_t nbuf;
36 	void *nptr;
37 	int n;
38 
39 	nbuf_init(&nbuf, m, dummy_ifp);
40 
41 	nptr = nbuf_advance(&nbuf, (random() % 16) + 1, (random() % 16) + 1);
42 	mbuf_consistency_check(&nbuf);
43 	assert(nptr != NULL);
44 	nbuf_reset(&nbuf);
45 
46 	for (n = 0; ; ) {
47 		char d[4 + 1];
48 
49 		nptr = nbuf_ensure_contig(&nbuf, sizeof(uint32_t));
50 		if (nptr == NULL) {
51 			break;
52 		}
53 		mbuf_consistency_check(&nbuf);
54 		memcpy(&d, nptr, sizeof(uint32_t));
55 
56 		d[sizeof(d) - 1] = '\0';
57 		strcat(s, d);
58 
59 		if (n + sizeof(uint32_t) == MBUF_CHAIN_LEN) {
60 			assert(nbuf_advance(&nbuf, sizeof(uint32_t) - 1, 0));
61 			assert(!nbuf_advance(&nbuf, 1, 0));
62 			break;
63 		}
64 		if (!nbuf_advance(&nbuf, sizeof(uint32_t), 0)) {
65 			break;
66 		}
67 		n += sizeof(uint32_t);
68 	}
69 	mbuf_consistency_check(&nbuf);
70 	return s;
71 }
72 
73 static char *
74 mbuf_getstring(struct mbuf *m)
75 {
76 	char *s = kmem_zalloc(MBUF_CHAIN_LEN + 1, KM_SLEEP);
77 	u_int tlen = 0;
78 
79 	while (m) {
80 		int len = m->m_len;
81 		char *d = m->m_data;
82 		while (len--) {
83 			s[tlen++] = *d++;
84 		}
85 		m = m->m_next;
86 	}
87 	return s;
88 }
89 
90 static struct mbuf *
91 mbuf_alloc_with_off(size_t off, int len)
92 {
93 	struct mbuf *m;
94 
95 	KASSERT(off + len < MLEN);
96 	m = m_get(M_WAITOK, MT_DATA);
97 	m->m_data = (char *)m->m_data + off;
98 	m->m_len = len;
99 	return m;
100 }
101 
102 /*
103  * Create an mbuf chain, each of 1 byte size.
104  */
105 static struct mbuf *
106 mbuf_bytesize(size_t clen)
107 {
108 	struct mbuf *m0 = NULL, *m = NULL;
109 	u_int i, n;
110 
111 	/* Chain of clen (e.g. 128) mbufs, each storing 1 byte of data. */
112 	for (i = 0, n = 0; i < clen; i++) {
113 		/* Range of offset: 0 .. 15. */
114 		m0 = mbuf_alloc_with_off(n & 0xf, 1);
115 
116 		/* Fill data with letters from 'a' to 'z'. */
117 		memset(m0->m_data, 'a' + n, 1);
118 		n = ('a' + n) < 'z' ? n + 1 : 0;
119 
120 		/* Next mbuf.. */
121 		m0->m_next = m;
122 		m = m0;
123 	}
124 
125 	m0 = m_gethdr(M_WAITOK, MT_HEADER);
126 	m0->m_pkthdr.len = clen;
127 	m0->m_len = 0;
128 	m0->m_next = m;
129 	return m0;
130 }
131 
132 /*
133  * Generate random amount of mbufs, with random offsets and lengths.
134  */
135 static struct mbuf *
136 mbuf_random_len(size_t chain_len)
137 {
138 	struct mbuf *m0 = NULL, *m = NULL;
139 	u_int tlen = 0, n = 0;
140 
141 	while (tlen < chain_len) {
142 		u_int off, len;
143 		char *d;
144 
145 		/* Random offset and length range: 1 .. 16. */
146 		off = (random() % 16) + 1;
147 		len = (random() % 16) + 1;
148 
149 		/* Do not exceed 128 bytes of total length. */
150 		if (tlen + len > chain_len) {
151 			len = chain_len - tlen;
152 		}
153 		tlen += len;
154 
155 		/* Consistently fill data with letters from 'a' to 'z'. */
156 		m0 = mbuf_alloc_with_off(off, len);
157 		d = m0->m_data;
158 		while (len--) {
159 			*d++ = ('a' + n);
160 			n = ('a' + n) < 'z' ? n + 1 : 0;
161 		}
162 
163 		/* Next mbuf.. */
164 		m0->m_next = m;
165 		m = m0;
166 	}
167 	KASSERT(tlen == chain_len);
168 
169 	m0 = m_gethdr(M_WAITOK, MT_HEADER);
170 	m0->m_pkthdr.len = tlen;
171 	m0->m_next = m;
172 	m0->m_len = 0;
173 	return m0;
174 }
175 
176 static bool
177 validate_mbuf_data(bool verbose, char *bufa, char *bufb)
178 {
179 	bool ret = (strcmp(bufa, bufb) == 0);
180 
181 	if (verbose) {
182 		printf("Buffer A: %s\nBuffer B: %s\n", bufa, bufb);
183 	}
184 	kmem_free(bufa, MBUF_CHAIN_LEN + 1);
185 	kmem_free(bufb, MBUF_CHAIN_LEN + 1);
186 	return ret;
187 }
188 
189 bool
190 npf_nbuf_test(bool verbose)
191 {
192 	struct mbuf *m1, *m2;
193 	char *bufa, *bufb;
194 	bool fail = false;
195 
196 	m1 = mbuf_random_len(MBUF_CHAIN_LEN);
197 	bufa = mbuf_getstring(m1);
198 	bufb = parse_nbuf_chain(m1);
199 	fail |= !validate_mbuf_data(verbose, bufa, bufb);
200 
201 	m2 = mbuf_bytesize(MBUF_CHAIN_LEN);
202 	bufa = mbuf_getstring(m2);
203 	bufb = parse_nbuf_chain(m2);
204 	fail |= !validate_mbuf_data(verbose, bufa, bufb);
205 
206 	return !fail;
207 }
208