1 /* SPDX-License-Identifier: GPL-2.0 */ 2 3 #ifndef __LINUX_TPM_EVENTLOG_H__ 4 #define __LINUX_TPM_EVENTLOG_H__ 5 6 #include <linux/tpm.h> 7 8 #define TCG_EVENT_NAME_LEN_MAX 255 9 #define MAX_TEXT_EVENT 1000 /* Max event string length */ 10 #define ACPI_TCPA_SIG "TCPA" /* 0x41504354 /'TCPA' */ 11 12 #define EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2 0x1 13 #define EFI_TCG2_EVENT_LOG_FORMAT_TCG_2 0x2 14 15 #ifdef CONFIG_PPC64 16 #define do_endian_conversion(x) be32_to_cpu(x) 17 #else 18 #define do_endian_conversion(x) x 19 #endif 20 21 enum bios_platform_class { 22 BIOS_CLIENT = 0x00, 23 BIOS_SERVER = 0x01, 24 }; 25 26 struct tcpa_event { 27 u32 pcr_index; 28 u32 event_type; 29 u8 pcr_value[20]; /* SHA1 */ 30 u32 event_size; 31 u8 event_data[0]; 32 }; 33 34 enum tcpa_event_types { 35 PREBOOT = 0, 36 POST_CODE, 37 UNUSED, 38 NO_ACTION, 39 SEPARATOR, 40 ACTION, 41 EVENT_TAG, 42 SCRTM_CONTENTS, 43 SCRTM_VERSION, 44 CPU_MICROCODE, 45 PLATFORM_CONFIG_FLAGS, 46 TABLE_OF_DEVICES, 47 COMPACT_HASH, 48 IPL, 49 IPL_PARTITION_DATA, 50 NONHOST_CODE, 51 NONHOST_CONFIG, 52 NONHOST_INFO, 53 }; 54 55 struct tcpa_pc_event { 56 u32 event_id; 57 u32 event_size; 58 u8 event_data[0]; 59 }; 60 61 enum tcpa_pc_event_ids { 62 SMBIOS = 1, 63 BIS_CERT, 64 POST_BIOS_ROM, 65 ESCD, 66 CMOS, 67 NVRAM, 68 OPTION_ROM_EXEC, 69 OPTION_ROM_CONFIG, 70 OPTION_ROM_MICROCODE = 10, 71 S_CRTM_VERSION, 72 S_CRTM_CONTENTS, 73 POST_CONTENTS, 74 HOST_TABLE_OF_DEVICES, 75 }; 76 77 /* http://www.trustedcomputinggroup.org/tcg-efi-protocol-specification/ */ 78 79 struct tcg_efi_specid_event_algs { 80 u16 alg_id; 81 u16 digest_size; 82 } __packed; 83 84 struct tcg_efi_specid_event_head { 85 u8 signature[16]; 86 u32 platform_class; 87 u8 spec_version_minor; 88 u8 spec_version_major; 89 u8 spec_errata; 90 u8 uintnsize; 91 u32 num_algs; 92 struct tcg_efi_specid_event_algs digest_sizes[]; 93 } __packed; 94 95 struct tcg_pcr_event { 96 u32 pcr_idx; 97 u32 event_type; 98 u8 digest[20]; 99 u32 event_size; 100 u8 event[0]; 101 } __packed; 102 103 struct tcg_event_field { 104 u32 event_size; 105 u8 event[0]; 106 } __packed; 107 108 struct tcg_pcr_event2_head { 109 u32 pcr_idx; 110 u32 event_type; 111 u32 count; 112 struct tpm_digest digests[]; 113 } __packed; 114 115 struct tcg_algorithm_size { 116 u16 algorithm_id; 117 u16 algorithm_size; 118 }; 119 120 struct tcg_algorithm_info { 121 u8 signature[16]; 122 u32 platform_class; 123 u8 spec_version_minor; 124 u8 spec_version_major; 125 u8 spec_errata; 126 u8 uintn_size; 127 u32 number_of_algorithms; 128 struct tcg_algorithm_size digest_sizes[]; 129 }; 130 131 #ifndef TPM_MEMREMAP 132 #define TPM_MEMREMAP(start, size) NULL 133 #endif 134 135 #ifndef TPM_MEMUNMAP 136 #define TPM_MEMUNMAP(start, size) do{} while(0) 137 #endif 138 139 /** 140 * __calc_tpm2_event_size - calculate the size of a TPM2 event log entry 141 * @event: Pointer to the event whose size should be calculated 142 * @event_header: Pointer to the initial event containing the digest lengths 143 * @do_mapping: Whether or not the event needs to be mapped 144 * 145 * The TPM2 event log format can contain multiple digests corresponding to 146 * separate PCR banks, and also contains a variable length of the data that 147 * was measured. This requires knowledge of how long each digest type is, 148 * and this information is contained within the first event in the log. 149 * 150 * We calculate the length by examining the number of events, and then looking 151 * at each event in turn to determine how much space is used for events in 152 * total. Once we've done this we know the offset of the data length field, 153 * and can calculate the total size of the event. 154 * 155 * Return: size of the event on success, <0 on failure 156 */ 157 158 static inline int __calc_tpm2_event_size(struct tcg_pcr_event2_head *event, 159 struct tcg_pcr_event *event_header, 160 bool do_mapping) 161 { 162 struct tcg_efi_specid_event_head *efispecid; 163 struct tcg_event_field *event_field; 164 void *mapping = NULL; 165 int mapping_size; 166 void *marker; 167 void *marker_start; 168 u32 halg_size; 169 size_t size; 170 u16 halg; 171 int i; 172 int j; 173 174 marker = event; 175 marker_start = marker; 176 marker = marker + sizeof(event->pcr_idx) + sizeof(event->event_type) 177 + sizeof(event->count); 178 179 /* Map the event header */ 180 if (do_mapping) { 181 mapping_size = marker - marker_start; 182 mapping = TPM_MEMREMAP((unsigned long)marker_start, 183 mapping_size); 184 if (!mapping) { 185 size = 0; 186 goto out; 187 } 188 } else { 189 mapping = marker_start; 190 } 191 192 event = (struct tcg_pcr_event2_head *)mapping; 193 194 efispecid = (struct tcg_efi_specid_event_head *)event_header->event; 195 196 /* Check if event is malformed. */ 197 if (event->count > efispecid->num_algs) { 198 size = 0; 199 goto out; 200 } 201 202 for (i = 0; i < event->count; i++) { 203 halg_size = sizeof(event->digests[i].alg_id); 204 205 /* Map the digest's algorithm identifier */ 206 if (do_mapping) { 207 TPM_MEMUNMAP(mapping, mapping_size); 208 mapping_size = halg_size; 209 mapping = TPM_MEMREMAP((unsigned long)marker, 210 mapping_size); 211 if (!mapping) { 212 size = 0; 213 goto out; 214 } 215 } else { 216 mapping = marker; 217 } 218 219 memcpy(&halg, mapping, halg_size); 220 marker = marker + halg_size; 221 222 for (j = 0; j < efispecid->num_algs; j++) { 223 if (halg == efispecid->digest_sizes[j].alg_id) { 224 marker += 225 efispecid->digest_sizes[j].digest_size; 226 break; 227 } 228 } 229 /* Algorithm without known length. Such event is unparseable. */ 230 if (j == efispecid->num_algs) { 231 size = 0; 232 goto out; 233 } 234 } 235 236 /* 237 * Map the event size - we don't read from the event itself, so 238 * we don't need to map it 239 */ 240 if (do_mapping) { 241 TPM_MEMUNMAP(mapping, mapping_size); 242 mapping_size += sizeof(event_field->event_size); 243 mapping = TPM_MEMREMAP((unsigned long)marker, 244 mapping_size); 245 if (!mapping) { 246 size = 0; 247 goto out; 248 } 249 } else { 250 mapping = marker; 251 } 252 253 event_field = (struct tcg_event_field *)mapping; 254 255 marker = marker + sizeof(event_field->event_size) 256 + event_field->event_size; 257 size = marker - marker_start; 258 259 if ((event->event_type == 0) && (event_field->event_size == 0)) 260 size = 0; 261 out: 262 if (do_mapping) 263 TPM_MEMUNMAP(mapping, mapping_size); 264 return size; 265 } 266 267 #endif 268