1 /*
2 * SPDX-License-Identifier: Apache-2.0
3 *
4 * Copyright (c) 2019 JUUL Labs
5 * Copyright (c) 2020 Arm Limited
6 * Copyright (c) 2025 Nordic Semiconductor ASA
7 *
8 * Licensed under the Apache License, Version 2.0 (the "License");
9 * you may not use this file except in compliance with the License.
10 * You may obtain a copy of the License at
11 *
12 * http://www.apache.org/licenses/LICENSE-2.0
13 *
14 * Unless required by applicable law or agreed to in writing, software
15 * distributed under the License is distributed on an "AS IS" BASIS,
16 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
17 * See the License for the specific language governing permissions and
18 * limitations under the License.
19 */
20
21 #include <stddef.h>
22
23 #include "bootutil/bootutil.h"
24 #include "bootutil/image.h"
25 #include "bootutil_priv.h"
26
27 /*
28 * Initialize a TLV iterator.
29 *
30 * @param it An iterator struct
31 * @param hdr image_header of the slot's image
32 * @param fap flash_area of the slot which is storing the image
33 * @param type Type of TLV to look for
34 * @param prot true if TLV has to be stored in the protected area, false otherwise
35 *
36 * @returns 0 if the TLV iterator was successfully started
37 * -1 on errors
38 */
39 int
bootutil_tlv_iter_begin(struct image_tlv_iter * it,const struct image_header * hdr,const struct flash_area * fap,uint16_t type,bool prot)40 bootutil_tlv_iter_begin(struct image_tlv_iter *it, const struct image_header *hdr,
41 const struct flash_area *fap, uint16_t type, bool prot)
42 {
43 uint32_t off_;
44 struct image_tlv_info info;
45
46 if (it == NULL || hdr == NULL || fap == NULL) {
47 return -1;
48 }
49
50 #if defined(MCUBOOT_SWAP_USING_OFFSET)
51 off_ = BOOT_TLV_OFF(hdr) + it->start_off;
52 #else
53 off_ = BOOT_TLV_OFF(hdr);
54 #endif
55
56 if (LOAD_IMAGE_DATA(hdr, fap, off_, &info, sizeof(info))) {
57 return -1;
58 }
59
60 if (info.it_magic == IMAGE_TLV_PROT_INFO_MAGIC) {
61 if (hdr->ih_protect_tlv_size != info.it_tlv_tot) {
62 return -1;
63 }
64
65 if (LOAD_IMAGE_DATA(hdr, fap, off_ + info.it_tlv_tot,
66 &info, sizeof(info))) {
67 return -1;
68 }
69 } else if (hdr->ih_protect_tlv_size != 0) {
70 return -1;
71 }
72
73 if (info.it_magic != IMAGE_TLV_INFO_MAGIC) {
74 return -1;
75 }
76
77 it->hdr = hdr;
78 it->fap = fap;
79 it->type = type;
80 it->prot = prot;
81 it->prot_end = off_ + it->hdr->ih_protect_tlv_size;
82 it->tlv_end = off_ + it->hdr->ih_protect_tlv_size + info.it_tlv_tot;
83 // position on first TLV
84 it->tlv_off = off_ + sizeof(info);
85 return 0;
86 }
87
88 /*
89 * Find next TLV
90 *
91 * @param it The image TLV iterator struct
92 * @param off The offset of the TLV's payload in flash
93 * @param len The length of the TLV's payload
94 * @param type If not NULL returns the type of TLV found
95 *
96 * @returns 0 if a TLV with with matching type was found
97 * 1 if no more TLVs with matching type are available
98 * -1 on errors
99 */
100 int
bootutil_tlv_iter_next(struct image_tlv_iter * it,uint32_t * off,uint16_t * len,uint16_t * type)101 bootutil_tlv_iter_next(struct image_tlv_iter *it, uint32_t *off, uint16_t *len,
102 uint16_t *type)
103 {
104 struct image_tlv tlv;
105 int rc;
106
107 if (it == NULL || it->hdr == NULL || it->fap == NULL) {
108 return -1;
109 }
110
111 while (it->tlv_off < it->tlv_end) {
112 if (it->hdr->ih_protect_tlv_size > 0 && it->tlv_off == it->prot_end) {
113 it->tlv_off += sizeof(struct image_tlv_info);
114 }
115
116 rc = LOAD_IMAGE_DATA(it->hdr, it->fap, it->tlv_off, &tlv, sizeof tlv);
117 if (rc) {
118 return -1;
119 }
120
121 /* No more TLVs in the protected area */
122 if (it->prot && it->tlv_off >= it->prot_end) {
123 return 1;
124 }
125
126 if (it->type == IMAGE_TLV_ANY || tlv.it_type == it->type) {
127 if (type != NULL) {
128 *type = tlv.it_type;
129 }
130 *off = it->tlv_off + sizeof(tlv);
131 *len = tlv.it_len;
132 it->tlv_off += sizeof(tlv) + tlv.it_len;
133 return 0;
134 }
135
136 it->tlv_off += sizeof(tlv) + tlv.it_len;
137 }
138
139 return 1;
140 }
141
142 /*
143 * Return if a TLV entry is in the protected area.
144 *
145 * @param it The image TLV iterator struct
146 * @param off The offset of the entry to check.
147 *
148 * @return 0 if this TLV iterator entry is not protected.
149 * 1 if this TLV iterator entry is in the protected region
150 * -1 if the iterator is invalid.
151 */
152 int
bootutil_tlv_iter_is_prot(struct image_tlv_iter * it,uint32_t off)153 bootutil_tlv_iter_is_prot(struct image_tlv_iter *it, uint32_t off)
154 {
155 if (it == NULL || it->hdr == NULL || it->fap == NULL) {
156 return -1;
157 }
158
159 return off < it->prot_end;
160 }
161
