2 * Copyright (c) 2003, 2004 David Young. All rights reserved.
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 * 3. The name of David Young may not be used to endorse or promote
13 * products derived from this software without specific prior
16 * THIS SOFTWARE IS PROVIDED BY DAVID YOUNG ``AS IS'' AND ANY
17 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
18 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
19 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL DAVID
20 * YOUNG BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
21 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
22 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
25 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
36 #include "netdissect-stdinc.h"
38 #include "netdissect.h"
44 nd_cpack_next_boundary(const uint8_t *buf, const uint8_t *p, size_t alignment)
46 size_t misalignment = (size_t)(p - buf) % alignment;
48 if (misalignment == 0)
51 return p + (alignment - misalignment);
54 /* Advance to the next wordsize boundary. Return NULL if fewer than
55 * wordsize bytes remain in the buffer after the boundary. Otherwise,
56 * return a pointer to the boundary.
59 nd_cpack_align_and_reserve(struct cpack_state *cs, size_t wordsize)
63 /* Ensure alignment. */
64 next = nd_cpack_next_boundary(cs->c_buf, cs->c_next, wordsize);
66 /* Too little space for wordsize bytes? */
67 if (next - cs->c_buf + wordsize > cs->c_len)
73 /* Advance by N bytes without returning them. */
75 nd_cpack_advance(struct cpack_state *cs, const size_t toskip)
78 if (cs->c_next - cs->c_buf + toskip > cs->c_len)
85 nd_cpack_init(struct cpack_state *cs, const uint8_t *buf, size_t buflen)
87 memset(cs, 0, sizeof(*cs));
91 cs->c_next = cs->c_buf;
96 /* Unpack a 64-bit unsigned integer. */
98 nd_cpack_uint64(netdissect_options *ndo, struct cpack_state *cs, uint64_t *u)
102 if ((next = nd_cpack_align_and_reserve(cs, sizeof(*u))) == NULL)
105 *u = GET_LE_U_8(next);
107 /* Move pointer past the uint64_t. */
108 cs->c_next = next + sizeof(*u);
112 /* Unpack a 64-bit signed integer. */
114 nd_cpack_int64(netdissect_options *ndo, struct cpack_state *cs, int64_t *u)
118 if ((next = nd_cpack_align_and_reserve(cs, sizeof(*u))) == NULL)
121 *u = GET_LE_S_8(next);
123 /* Move pointer past the int64_t. */
124 cs->c_next = next + sizeof(*u);
128 /* Unpack a 32-bit unsigned integer. */
130 nd_cpack_uint32(netdissect_options *ndo, struct cpack_state *cs, uint32_t *u)
134 if ((next = nd_cpack_align_and_reserve(cs, sizeof(*u))) == NULL)
137 *u = GET_LE_U_4(next);
139 /* Move pointer past the uint32_t. */
140 cs->c_next = next + sizeof(*u);
144 /* Unpack a 32-bit signed integer. */
146 nd_cpack_int32(netdissect_options *ndo, struct cpack_state *cs, int32_t *u)
150 if ((next = nd_cpack_align_and_reserve(cs, sizeof(*u))) == NULL)
153 *u = GET_LE_S_4(next);
155 /* Move pointer past the int32_t. */
156 cs->c_next = next + sizeof(*u);
160 /* Unpack a 16-bit unsigned integer. */
162 nd_cpack_uint16(netdissect_options *ndo, struct cpack_state *cs, uint16_t *u)
166 if ((next = nd_cpack_align_and_reserve(cs, sizeof(*u))) == NULL)
169 *u = GET_LE_U_2(next);
171 /* Move pointer past the uint16_t. */
172 cs->c_next = next + sizeof(*u);
176 /* Unpack a 16-bit signed integer. */
178 nd_cpack_int16(netdissect_options *ndo, struct cpack_state *cs, int16_t *u)
182 if ((next = nd_cpack_align_and_reserve(cs, sizeof(*u))) == NULL)
185 *u = GET_LE_S_2(next);
187 /* Move pointer past the int16_t. */
188 cs->c_next = next + sizeof(*u);
192 /* Unpack an 8-bit unsigned integer. */
194 nd_cpack_uint8(netdissect_options *ndo, struct cpack_state *cs, uint8_t *u)
197 if ((size_t)(cs->c_next - cs->c_buf) >= cs->c_len)
200 *u = GET_U_1(cs->c_next);
202 /* Move pointer past the uint8_t. */
207 /* Unpack an 8-bit signed integer. */
209 nd_cpack_int8(netdissect_options *ndo, struct cpack_state *cs, int8_t *u)
212 if ((size_t)(cs->c_next - cs->c_buf) >= cs->c_len)
215 *u = GET_S_1(cs->c_next);
217 /* Move pointer past the int8_t. */