1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 * 26 * Copyright 2021 OmniOS Community Edition (OmniOSce) Association. 27 * Copyright 2023 Oxide Computer Company 28 */ 29 30 #include <sys/types.h> 31 #include <sys/ucode.h> 32 #include <sys/ucode_intel.h> 33 #ifdef _KERNEL 34 #include <sys/systm.h> 35 #else 36 #include <strings.h> 37 #endif 38 39 /* 40 * Refer to 41 * Intel 64 and IA-32 Architectures Software Developers's Manual 42 * Chapter 9.11 Microcode Update Facilities [1] 43 * for details. 44 */ 45 46 /* 47 * Validates the microcode header. 48 * Returns EM_OK on success, EM_HEADER on failure. 49 */ 50 ucode_errno_t 51 ucode_header_validate_intel(ucode_header_intel_t *uhp) 52 { 53 uint32_t header_size, body_size, total_size; 54 55 if (uhp == NULL) 56 return (EM_HEADER); 57 58 /* 59 * The only header version number supported is 1. 60 */ 61 if (uhp->uh_header_ver != 0x1) 62 return (EM_HEADER); 63 64 header_size = UCODE_HEADER_SIZE_INTEL; 65 total_size = UCODE_TOTAL_SIZE_INTEL(uhp->uh_total_size); 66 body_size = UCODE_BODY_SIZE_INTEL(uhp->uh_body_size); 67 68 /* 69 * The body size field of the microcode code header specifies the size 70 * of the encrypted data section, its value must be a multiple of the 71 * size of DWORD. The total size field must be in multiples of 1K 72 * bytes. 73 */ 74 if ((body_size % sizeof (int)) || 75 (total_size < (header_size + body_size)) || 76 (total_size % UCODE_KB(1))) 77 78 return (EM_HEADER); 79 80 /* 81 * Sanity check to avoid reading bogus files 82 */ 83 if (total_size < UCODE_MIN_SIZE || total_size > UCODE_MAX_SIZE) 84 return (EM_HEADER); 85 86 /* 87 * If there is extended signature table, total_size is the sum of 88 * header_size 89 * body_size 90 * sizeof (struct ucode_ext_table) 91 * n * sizeof (struct ucode_ext_sig) 92 * where n is indicated by uet_count in struct ucode_ext_table. 93 */ 94 if (total_size > (header_size + body_size)) { 95 if ((total_size - body_size - header_size - 96 UCODE_EXT_TABLE_SIZE_INTEL) % UCODE_EXT_SIG_SIZE_INTEL) { 97 98 return (EM_HEADER); 99 } 100 } 101 102 return (EM_OK); 103 } 104 105 /* 106 * Returns checksum. 107 */ 108 uint32_t 109 ucode_checksum_intel(uint32_t sum, uint32_t size, uint8_t *code) 110 { 111 int i; 112 uint32_t *lcode = (uint32_t *)(intptr_t)code; 113 114 i = size >> 2; 115 while (i--) 116 sum += lcode[i]; 117 118 return (sum); 119 } 120 121 uint32_t 122 ucode_checksum_intel_extsig(ucode_header_intel_t *uhp, 123 ucode_ext_sig_intel_t *uesp) 124 { 125 /* 126 * From [1], table 9-7, the checksum field contained in the extended 127 * patch signature is the checksum across the entire update which would 128 * result if the primary processor signature and processor flags were 129 * replaced with the values from this entry. 130 * 131 * We can therefore just calculate the difference in the checksum 132 * between the old and new values and return that to the caller. If the 133 * difference is zero then the checksum for the patch is valid. 134 */ 135 uint32_t diff; 136 137 diff = uesp->ues_signature + 138 uesp->ues_proc_flags + uesp->ues_checksum; 139 diff -= uhp->uh_signature + uhp->uh_proc_flags + 140 uhp->uh_checksum; 141 142 return (diff); 143 } 144 145 ucode_errno_t 146 ucode_validate_intel(uint8_t *ucodep, int size) 147 { 148 uint32_t header_size = UCODE_HEADER_SIZE_INTEL; 149 int remaining; 150 151 if (ucodep == NULL || size <= 0) 152 return (EM_INVALIDARG); 153 154 for (remaining = size; remaining > 0; ) { 155 uint32_t total_size, body_size, ext_size; 156 ucode_header_intel_t *uhp; 157 uint8_t *curbuf = &ucodep[size - remaining]; 158 ucode_errno_t rc; 159 160 uhp = (ucode_header_intel_t *)curbuf; 161 162 if ((rc = ucode_header_validate_intel(uhp)) != EM_OK) 163 return (rc); 164 165 total_size = UCODE_TOTAL_SIZE_INTEL(uhp->uh_total_size); 166 167 if (ucode_checksum_intel(0, total_size, curbuf) != 0) 168 return (EM_CHECKSUM); 169 170 body_size = UCODE_BODY_SIZE_INTEL(uhp->uh_body_size); 171 ext_size = total_size - (header_size + body_size); 172 173 if (ext_size > 0) { 174 ucode_ext_table_intel_t *ext; 175 uint32_t i; 176 177 ext = (ucode_ext_table_intel_t *) 178 &curbuf[header_size + body_size]; 179 180 if (ucode_checksum_intel(0, ext_size, (uint8_t *)ext)) 181 return (EM_EXTCHECKSUM); 182 183 for (i = 0; i < ext->uet_count; i++) { 184 ucode_ext_sig_intel_t *sig = 185 &ext->uet_ext_sig[i]; 186 187 if (ucode_checksum_intel_extsig(uhp, sig) != 0) 188 return (EM_SIGCHECKSUM); 189 } 190 } 191 192 remaining -= total_size; 193 } 194 return (EM_OK); 195 } 196