Sergii Dmytruk | 04bd965 | 2023-11-17 19:31:20 +0200 | [diff] [blame] | 1 | /* SPDX-License-Identifier: GPL-2.0-or-later */ |
| 2 | |
| 3 | #include "vs.h" |
| 4 | |
| 5 | #include <limits.h> |
| 6 | #include <stdio.h> |
| 7 | #include <stdlib.h> |
| 8 | #include <string.h> |
| 9 | |
| 10 | #include "udk2017.h" |
| 11 | #include "utils.h" |
| 12 | |
| 13 | static size_t get_var_hdr_size(bool auth_vars) |
| 14 | { |
| 15 | if (auth_vars) |
| 16 | return sizeof(AUTHENTICATED_VARIABLE_HEADER); |
| 17 | return sizeof(VARIABLE_HEADER); |
| 18 | } |
| 19 | |
| 20 | struct var_store_t vs_load(struct mem_range_t vs_data, bool auth_vars) |
| 21 | { |
| 22 | uint8_t *var_hdr = vs_data.start; |
| 23 | |
| 24 | struct var_store_t vs = { |
| 25 | .auth_vars = auth_vars, |
| 26 | .vars = NULL, |
| 27 | }; |
| 28 | |
| 29 | struct var_t *last_var = NULL; |
| 30 | |
| 31 | const size_t var_hdr_size = get_var_hdr_size(auth_vars); |
| 32 | while (var_hdr + var_hdr_size < vs_data.start + vs_data.length) { |
| 33 | uint16_t start_id; |
| 34 | uint8_t state; |
| 35 | struct var_t var = {0}; |
| 36 | uint8_t *var_data = var_hdr; |
| 37 | |
| 38 | if (auth_vars) { |
| 39 | const AUTHENTICATED_VARIABLE_HEADER *auth_hdr = |
| 40 | (void *)var_data; |
| 41 | |
| 42 | start_id = auth_hdr->StartId; |
| 43 | state = auth_hdr->State; |
| 44 | |
| 45 | var.reserved = auth_hdr->Reserved; |
| 46 | var.attrs = auth_hdr->Attributes; |
| 47 | var.name_size = auth_hdr->NameSize; |
| 48 | var.data_size = auth_hdr->DataSize; |
| 49 | var.guid = auth_hdr->VendorGuid; |
| 50 | } else { |
| 51 | const VARIABLE_HEADER *no_auth_hdr = (void *)var_data; |
| 52 | |
| 53 | start_id = no_auth_hdr->StartId; |
| 54 | state = no_auth_hdr->State; |
| 55 | |
| 56 | var.reserved = no_auth_hdr->Reserved; |
| 57 | var.attrs = no_auth_hdr->Attributes; |
| 58 | var.name_size = no_auth_hdr->NameSize; |
| 59 | var.data_size = no_auth_hdr->DataSize; |
| 60 | var.guid = no_auth_hdr->VendorGuid; |
| 61 | } |
| 62 | |
| 63 | var_hdr += HEADER_ALIGN(var_hdr_size + |
| 64 | var.name_size + |
| 65 | var.data_size); |
| 66 | |
| 67 | if (start_id != VARIABLE_DATA) |
| 68 | break; |
| 69 | |
| 70 | if (state != VAR_ADDED) |
| 71 | continue; |
| 72 | |
| 73 | if (var.data_size == UINT32_MAX || |
| 74 | var.name_size == UINT32_MAX || |
| 75 | var.attrs == UINT32_MAX) |
| 76 | continue; |
| 77 | |
| 78 | CHAR16 *name = (void *)(var_data + var_hdr_size); |
| 79 | var.name = xmalloc(var.name_size); |
| 80 | memcpy(var.name, name, var.name_size); |
| 81 | |
| 82 | uint8_t *data = |
| 83 | (void *)(var_data + var_hdr_size + var.name_size); |
| 84 | var.data = xmalloc(var.data_size); |
| 85 | memcpy(var.data, data, var.data_size); |
| 86 | |
| 87 | struct var_t *var_node = xmalloc(sizeof(*var_node)); |
| 88 | *var_node = var; |
| 89 | if (last_var != NULL) |
| 90 | last_var->next = var_node; |
| 91 | else if (vs.vars == NULL) |
| 92 | vs.vars = var_node; |
| 93 | last_var = var_node; |
| 94 | } |
| 95 | |
| 96 | return vs; |
| 97 | } |
| 98 | |
| 99 | static void store_var(const struct var_t *var, bool auth_vars, uint8_t *data) |
| 100 | { |
| 101 | if (auth_vars) { |
| 102 | AUTHENTICATED_VARIABLE_HEADER hdr; |
| 103 | memset(&hdr, 0xff, sizeof(hdr)); |
| 104 | |
| 105 | hdr.StartId = VARIABLE_DATA; |
| 106 | hdr.State = VAR_ADDED; |
| 107 | hdr.Reserved = var->reserved; |
| 108 | hdr.Attributes = var->attrs; |
| 109 | hdr.VendorGuid = var->guid; |
| 110 | hdr.NameSize = var->name_size; |
| 111 | hdr.DataSize = var->data_size; |
| 112 | |
| 113 | memcpy(data, &hdr, sizeof(hdr)); |
| 114 | data += sizeof(hdr); |
| 115 | } else { |
| 116 | VARIABLE_HEADER hdr; |
| 117 | memset(&hdr, 0xff, sizeof(hdr)); |
| 118 | |
| 119 | hdr.StartId = VARIABLE_DATA; |
| 120 | hdr.State = VAR_ADDED; |
| 121 | hdr.Reserved = var->reserved; |
| 122 | hdr.Attributes = var->attrs; |
| 123 | hdr.VendorGuid = var->guid; |
| 124 | hdr.NameSize = var->name_size; |
| 125 | hdr.DataSize = var->data_size; |
| 126 | |
| 127 | memcpy(data, &hdr, sizeof(hdr)); |
| 128 | data += sizeof(hdr); |
| 129 | } |
| 130 | |
| 131 | memcpy(data, var->name, var->name_size); |
| 132 | memcpy(data + var->name_size, var->data, var->data_size); |
| 133 | } |
| 134 | |
| 135 | bool vs_store(struct var_store_t *vs, struct mem_range_t vs_data) |
| 136 | { |
| 137 | uint8_t *out_data = vs_data.start; |
| 138 | |
| 139 | const size_t var_hdr_size = get_var_hdr_size(vs->auth_vars); |
| 140 | for (struct var_t *var = vs->vars; var != NULL; var = var->next) { |
| 141 | const size_t var_size = |
| 142 | var_hdr_size + var->name_size + var->data_size; |
| 143 | if (out_data + var_size > vs_data.start + vs_data.length) { |
| 144 | fprintf(stderr, |
| 145 | "Not enough space to serialize Variable Store.\n"); |
| 146 | return false; |
| 147 | } |
| 148 | |
| 149 | store_var(var, vs->auth_vars, out_data); |
| 150 | out_data += HEADER_ALIGN(var_size); |
| 151 | } |
| 152 | |
| 153 | // The rest is "uninitialized". |
| 154 | memset(out_data, 0xff, vs_data.length - (out_data - vs_data.start)); |
| 155 | |
| 156 | return true; |
| 157 | } |
| 158 | |
| 159 | struct var_t *vs_new_var(struct var_store_t *vs) |
| 160 | { |
| 161 | struct var_t *new_var = xmalloc(sizeof(*new_var)); |
| 162 | |
| 163 | memset(new_var, 0, sizeof(*new_var)); |
| 164 | new_var->attrs = EFI_VARIABLE_NON_VOLATILE |
| 165 | | EFI_VARIABLE_BOOTSERVICE_ACCESS |
| 166 | | EFI_VARIABLE_RUNTIME_ACCESS; |
| 167 | |
| 168 | struct var_t *var = vs->vars; |
| 169 | if (var == NULL) { |
| 170 | vs->vars = new_var; |
| 171 | } else { |
| 172 | while (var->next != NULL) |
| 173 | var = var->next; |
| 174 | var->next = new_var; |
| 175 | } |
| 176 | |
| 177 | return new_var; |
| 178 | } |
| 179 | |
| 180 | struct var_t *vs_find(struct var_store_t *vs, |
| 181 | const char name[], |
| 182 | const EFI_GUID *guid) |
| 183 | { |
| 184 | size_t name_size; |
| 185 | CHAR16 *uchar_name = to_uchars(name, &name_size); |
| 186 | |
| 187 | struct var_t *var; |
| 188 | for (var = vs->vars; var != NULL; var = var->next) { |
| 189 | if (var->name_size != name_size) |
| 190 | continue; |
| 191 | if (memcmp(var->name, uchar_name, name_size) != 0) |
| 192 | continue; |
| 193 | if (memcmp(&var->guid, guid, sizeof(*guid)) != 0) |
| 194 | continue; |
| 195 | break; |
| 196 | } |
| 197 | |
| 198 | free(uchar_name); |
| 199 | return var; |
| 200 | } |
| 201 | |
| 202 | static void free_var(struct var_t *var) |
| 203 | { |
| 204 | free(var->name); |
| 205 | free(var->data); |
| 206 | free(var); |
| 207 | } |
| 208 | |
| 209 | void vs_delete(struct var_store_t *vs, struct var_t *var) |
| 210 | { |
| 211 | if (vs->vars == var) { |
| 212 | vs->vars = var->next; |
| 213 | free_var(var); |
| 214 | return; |
| 215 | } |
| 216 | |
| 217 | for (struct var_t *v = vs->vars; v != NULL; v = v->next) { |
| 218 | if (v->next == var) { |
| 219 | v->next = var->next; |
| 220 | free_var(var); |
| 221 | return; |
| 222 | } |
| 223 | } |
| 224 | } |
| 225 | |
| 226 | void vs_free(struct var_store_t *vs) |
| 227 | { |
| 228 | for (struct var_t *next, *var = vs->vars; var != NULL; var = next) { |
| 229 | next = var->next; |
| 230 | free_var(var); |
| 231 | } |
| 232 | } |