mb/google/brya: Create rull variant
[coreboot2.git] / src / drivers / vpd / vpd_decode.c
blob944e21b2a7f4612fb53d05cad270b5fdc2bfe5e1
1 /* SPDX-License-Identifier: BSD-3-Clause */
3 /*
4 * This is a copy from upstream:
5 * https://chromium.googlesource.com/chromiumos/platform/vpd/+/master/lib/vpd_decode.c
6 */
7 #include "vpd_decode.h"
9 static int vpd_decode_len(
10 const u32 max_len, const u8 *in, u32 *length, u32 *decoded_len)
12 u8 more;
13 int i = 0;
15 if (!length || !decoded_len)
16 return VPD_DECODE_FAIL;
18 *length = 0;
19 do {
20 if (i >= max_len)
21 return VPD_DECODE_FAIL;
23 more = in[i] & 0x80;
24 *length <<= 7;
25 *length |= in[i] & 0x7f;
26 ++i;
27 } while (more);
29 *decoded_len = i;
30 return VPD_DECODE_OK;
33 static int vpd_decode_entry(
34 const u32 max_len, const u8 *input_buf, u32 *consumed,
35 const u8 **entry, u32 *entry_len)
37 u32 decoded_len;
39 if (vpd_decode_len(max_len - *consumed, &input_buf[*consumed],
40 entry_len, &decoded_len) != VPD_DECODE_OK)
41 return VPD_DECODE_FAIL;
42 if (max_len - *consumed < decoded_len)
43 return VPD_DECODE_FAIL;
45 *consumed += decoded_len;
46 *entry = input_buf + *consumed;
48 /* entry_len is untrusted data and must be checked again. */
49 if (max_len - *consumed < *entry_len)
50 return VPD_DECODE_FAIL;
52 *consumed += *entry_len;
53 return VPD_DECODE_OK;
56 int vpd_decode_string(
57 const u32 max_len, const u8 *input_buf, u32 *consumed,
58 vpd_decode_callback callback, void *callback_arg)
60 int type;
61 u32 key_len;
62 u32 value_len;
63 const u8 *key;
64 const u8 *value;
66 /* type */
67 if (*consumed >= max_len)
68 return VPD_DECODE_FAIL;
70 type = input_buf[*consumed];
72 switch (type) {
73 case VPD_TYPE_INFO:
74 case VPD_TYPE_STRING:
75 (*consumed)++;
77 if (vpd_decode_entry(max_len, input_buf, consumed, &key,
78 &key_len) != VPD_DECODE_OK)
79 return VPD_DECODE_FAIL;
81 if (vpd_decode_entry(max_len, input_buf, consumed, &value,
82 &value_len) != VPD_DECODE_OK)
83 return VPD_DECODE_FAIL;
85 if (type == VPD_TYPE_STRING)
86 return callback(key, key_len, value, value_len,
87 callback_arg);
88 break;
90 default:
91 return VPD_DECODE_FAIL;
94 return VPD_DECODE_OK;