1/*
2 * Copyright (c) 2015, ARM Limited and Contributors. All rights reserved.
3 *
4 * SPDX-License-Identifier: BSD-3-Clause
5 */
6
7#include <assert.h>
8#include <auth_common.h>
9#include <debug.h>
10#include <errno.h>
11#include <img_parser_mod.h>
12#include <limits.h>
13#include <stdint.h>
14#include <string.h>
15
16extern uintptr_t __PARSER_LIB_DESCS_START__;
17extern uintptr_t __PARSER_LIB_DESCS_END__;
18#define PARSER_LIB_DESCS_START	((uintptr_t) (&__PARSER_LIB_DESCS_START__))
19#define PARSER_LIB_DESCS_END	((uintptr_t) (&__PARSER_LIB_DESCS_END__))
20static unsigned int parser_lib_indices[IMG_MAX_TYPES];
21static img_parser_lib_desc_t *parser_lib_descs;
22
23#define INVALID_IDX		UINT_MAX
24
25static void validate_desc(img_parser_lib_desc_t *desc)
26{
27	assert(desc != NULL);
28	assert(desc->init != NULL);
29	assert(desc->name != NULL);
30	assert(desc->check_integrity != NULL);
31	assert(desc->get_auth_param != NULL);
32}
33
34void img_parser_init(void)
35{
36	unsigned int index, mod_num;
37
38	/* Initialise internal variables to invalid state */
39	for (index = 0; index < IMG_MAX_TYPES; index++) {
40		parser_lib_indices[index] = INVALID_IDX;
41	}
42
43	/* Calculate how many image parsers are registered. At least one parser
44	 * must be present */
45	mod_num = PARSER_LIB_DESCS_END - PARSER_LIB_DESCS_START;
46	mod_num /= sizeof(img_parser_lib_desc_t);
47	assert(mod_num > 0);
48
49	parser_lib_descs = (img_parser_lib_desc_t *) PARSER_LIB_DESCS_START;
50	for (index = 0; index < mod_num; index++) {
51
52		/* Check that the image parser library descriptor is valid */
53		validate_desc(&parser_lib_descs[index]);
54
55		/* Initialize image parser */
56		parser_lib_descs[index].init();
57
58		/* Ensure only one parser is registered for each image type */
59		assert(parser_lib_indices[parser_lib_descs[index].img_type] ==
60				INVALID_IDX);
61
62		/* Keep the index of this hash calculator */
63		parser_lib_indices[parser_lib_descs[index].img_type] = index;
64	}
65}
66
67int img_parser_check_integrity(img_type_t img_type,
68			       void *img_ptr, unsigned int img_len)
69{
70	unsigned int idx;
71
72	assert(img_ptr != NULL);
73	assert(img_len != 0);
74
75	/* No integrity checks on raw images */
76	if (img_type == IMG_RAW) {
77		return IMG_PARSER_OK;
78	}
79
80	/* Find the index of the required image parser */
81	idx = parser_lib_indices[img_type];
82	assert(idx != INVALID_IDX);
83
84	/* Call the function to check the image integrity */
85	return parser_lib_descs[idx].check_integrity(img_ptr, img_len);
86}
87
88/*
89 * Extract an authentication parameter from an image
90 *
91 * Parameters:
92 *   img_type: image type (certificate, raw image, etc)
93 *   type_desc: provides info to obtain the parameter
94 *   img_ptr: pointer to image data
95 *   img_len: image length
96 *   param_ptr: [out] stores a pointer to the parameter
97 *   param_len: [out] stores the length of the parameter
98 */
99int img_parser_get_auth_param(img_type_t img_type,
100			      const auth_param_type_desc_t *type_desc,
101			      void *img_ptr, unsigned int img_len,
102			      void **param_ptr, unsigned int *param_len)
103{
104	unsigned int idx;
105
106	assert(type_desc != NULL);
107	assert(img_ptr != NULL);
108	assert(img_len != 0);
109	assert(param_ptr != NULL);
110	assert(param_len != NULL);
111
112	/* In a raw image we can only get the data itself */
113	if (img_type == IMG_RAW) {
114		assert(type_desc->type == AUTH_PARAM_RAW_DATA);
115		*param_ptr = img_ptr;
116		*param_len = img_len;
117		return IMG_PARSER_OK;
118	}
119
120	/* Find the index of the required image parser library */
121	idx = parser_lib_indices[img_type];
122	assert(idx != INVALID_IDX);
123
124	/* Call the function to obtain the parameter */
125	return parser_lib_descs[idx].get_auth_param(type_desc, img_ptr, img_len,
126			param_ptr, param_len);
127}
128