1 /* 2 * Copyright (c) 2015-2020, ARM Limited and Contributors. All rights reserved. 3 * 4 * SPDX-License-Identifier: BSD-3-Clause 5 */ 6 7 #include <stddef.h> 8 #include <stdio.h> 9 #include <string.h> 10 #include <openssl/asn1.h> 11 #include <openssl/asn1t.h> 12 #include <openssl/err.h> 13 #include <openssl/x509v3.h> 14 15 #include "cmd_opt.h" 16 #include "ext.h" 17 18 DECLARE_ASN1_ITEM(ASN1_INTEGER) 19 DECLARE_ASN1_ITEM(X509_ALGOR) 20 DECLARE_ASN1_ITEM(ASN1_OCTET_STRING) 21 22 typedef struct { 23 X509_ALGOR *hashAlgorithm; 24 ASN1_OCTET_STRING *dataHash; 25 } HASH; 26 27 ASN1_SEQUENCE(HASH) = { 28 ASN1_SIMPLE(HASH, hashAlgorithm, X509_ALGOR), 29 ASN1_SIMPLE(HASH, dataHash, ASN1_OCTET_STRING), 30 } ASN1_SEQUENCE_END(HASH) 31 32 DECLARE_ASN1_FUNCTIONS(HASH) 33 IMPLEMENT_ASN1_FUNCTIONS(HASH) 34 35 /* 36 * This function adds the CoT extensions to the internal extension list 37 * maintained by OpenSSL so they can be used later. 38 * 39 * It also initializes the methods to print the contents of the extension. If an 40 * alias is specified in the CoT extension, we reuse the methods of the alias. 41 * Otherwise, only methods for V_ASN1_INTEGER and V_ASN1_OCTET_STRING are 42 * provided. Any other type will be printed as a raw ascii string. 43 * 44 * Return: 0 = success, Otherwise: error 45 */ 46 int ext_init(void) 47 { 48 cmd_opt_t cmd_opt; 49 ext_t *ext; 50 X509V3_EXT_METHOD *m; 51 int nid, ret; 52 unsigned int i; 53 54 for (i = 0; i < num_extensions; i++) { 55 ext = &extensions[i]; 56 /* Register command line option */ 57 if (ext->opt) { 58 cmd_opt.long_opt.name = ext->opt; 59 cmd_opt.long_opt.has_arg = required_argument; 60 cmd_opt.long_opt.flag = NULL; 61 cmd_opt.long_opt.val = CMD_OPT_EXT; 62 cmd_opt.help_msg = ext->help_msg; 63 cmd_opt_add(&cmd_opt); 64 } 65 /* Register the extension OID in OpenSSL */ 66 if (ext->oid == NULL) { 67 continue; 68 } 69 nid = OBJ_create(ext->oid, ext->sn, ext->ln); 70 if (ext->alias) { 71 X509V3_EXT_add_alias(nid, ext->alias); 72 } else { 73 m = &ext->method; 74 memset(m, 0x0, sizeof(X509V3_EXT_METHOD)); 75 switch (ext->asn1_type) { 76 case V_ASN1_INTEGER: 77 m->it = ASN1_ITEM_ref(ASN1_INTEGER); 78 m->i2s = (X509V3_EXT_I2S)i2s_ASN1_INTEGER; 79 m->s2i = (X509V3_EXT_S2I)s2i_ASN1_INTEGER; 80 break; 81 case V_ASN1_OCTET_STRING: 82 m->it = ASN1_ITEM_ref(ASN1_OCTET_STRING); 83 m->i2s = (X509V3_EXT_I2S)i2s_ASN1_OCTET_STRING; 84 m->s2i = (X509V3_EXT_S2I)s2i_ASN1_OCTET_STRING; 85 break; 86 default: 87 continue; 88 } 89 m->ext_nid = nid; 90 ret = X509V3_EXT_add(m); 91 if (!ret) { 92 ERR_print_errors_fp(stdout); 93 return 1; 94 } 95 } 96 } 97 return 0; 98 } 99 100 /* 101 * Create a new extension 102 * 103 * Extension ::= SEQUENCE { 104 * id OBJECT IDENTIFIER, 105 * critical BOOLEAN DEFAULT FALSE, 106 * value OCTET STRING } 107 * 108 * Parameters: 109 * pex: OpenSSL extension pointer (output parameter) 110 * nid: extension identifier 111 * crit: extension critical (EXT_NON_CRIT, EXT_CRIT) 112 * data: extension data. This data will be encapsulated in an Octet String 113 * 114 * Return: Extension address, NULL if error 115 */ 116 static 117 X509_EXTENSION *ext_new(int nid, int crit, unsigned char *data, int len) 118 { 119 X509_EXTENSION *ex; 120 ASN1_OCTET_STRING *ext_data; 121 122 /* Octet string containing the extension data */ 123 ext_data = ASN1_OCTET_STRING_new(); 124 ASN1_OCTET_STRING_set(ext_data, data, len); 125 126 /* Create the extension */ 127 ex = X509_EXTENSION_create_by_NID(NULL, nid, crit, ext_data); 128 129 /* The extension makes a copy of the data, so we can free this object */ 130 ASN1_OCTET_STRING_free(ext_data); 131 132 return ex; 133 } 134 135 /* 136 * Creates a x509v3 extension containing a hash 137 * 138 * DigestInfo ::= SEQUENCE { 139 * digestAlgorithm AlgorithmIdentifier, 140 * digest OCTET STRING 141 * } 142 * 143 * AlgorithmIdentifier ::= SEQUENCE { 144 * algorithm OBJECT IDENTIFIER, 145 * parameters ANY DEFINED BY algorithm OPTIONAL 146 * } 147 * 148 * Parameters: 149 * nid: extension identifier 150 * crit: extension critical (EXT_NON_CRIT, EXT_CRIT) 151 * md: hash algorithm 152 * buf: pointer to the buffer that contains the hash 153 * len: size of the hash in bytes 154 * 155 * Return: Extension address, NULL if error 156 */ 157 X509_EXTENSION *ext_new_hash(int nid, int crit, const EVP_MD *md, 158 unsigned char *buf, size_t len) 159 { 160 X509_EXTENSION *ex; 161 HASH *hash; 162 ASN1_OBJECT *algorithm; 163 unsigned char *p = NULL; 164 int sz; 165 166 /* HASH structure containing algorithm + hash */ 167 hash = HASH_new(); 168 if (hash == NULL) { 169 return NULL; 170 } 171 172 /* OBJECT_IDENTIFIER with hash algorithm */ 173 algorithm = OBJ_nid2obj(EVP_MD_type(md)); 174 if (algorithm == NULL) { 175 HASH_free(hash); 176 return NULL; 177 } 178 179 /* Create X509_ALGOR */ 180 hash->hashAlgorithm->algorithm = algorithm; 181 hash->hashAlgorithm->parameter = ASN1_TYPE_new(); 182 ASN1_TYPE_set(hash->hashAlgorithm->parameter, V_ASN1_NULL, NULL); 183 184 /* OCTET_STRING with the actual hash */ 185 ASN1_OCTET_STRING_set(hash->dataHash, buf, len); 186 187 /* DER encoded HASH */ 188 sz = i2d_HASH(hash, &p); 189 if ((sz <= 0) || (p == NULL)) { 190 HASH_free(hash); 191 return NULL; 192 } 193 194 /* Create the extension */ 195 ex = ext_new(nid, crit, p, sz); 196 197 /* Clean up */ 198 OPENSSL_free(p); 199 HASH_free(hash); 200 201 return ex; 202 } 203 204 /* 205 * Creates a x509v3 extension containing a nvcounter encapsulated in an ASN1 206 * Integer 207 * 208 * Parameters: 209 * pex: OpenSSL extension pointer (output parameter) 210 * nid: extension identifier 211 * crit: extension critical (EXT_NON_CRIT, EXT_CRIT) 212 * value: nvcounter value 213 * 214 * Return: Extension address, NULL if error 215 */ 216 X509_EXTENSION *ext_new_nvcounter(int nid, int crit, int value) 217 { 218 X509_EXTENSION *ex; 219 ASN1_INTEGER *counter; 220 unsigned char *p = NULL; 221 int sz; 222 223 /* Encode counter */ 224 counter = ASN1_INTEGER_new(); 225 ASN1_INTEGER_set(counter, value); 226 sz = i2d_ASN1_INTEGER(counter, &p); 227 228 /* Create the extension */ 229 ex = ext_new(nid, crit, p, sz); 230 231 /* Free objects */ 232 OPENSSL_free(p); 233 ASN1_INTEGER_free(counter); 234 235 return ex; 236 } 237 238 /* 239 * Creates a x509v3 extension containing a public key in DER format: 240 * 241 * SubjectPublicKeyInfo ::= SEQUENCE { 242 * algorithm AlgorithmIdentifier, 243 * subjectPublicKey BIT STRING } 244 * 245 * Parameters: 246 * pex: OpenSSL extension pointer (output parameter) 247 * nid: extension identifier 248 * crit: extension critical (EXT_NON_CRIT, EXT_CRIT) 249 * k: key 250 * 251 * Return: Extension address, NULL if error 252 */ 253 X509_EXTENSION *ext_new_key(int nid, int crit, EVP_PKEY *k) 254 { 255 X509_EXTENSION *ex; 256 unsigned char *p; 257 int sz; 258 259 /* Encode key */ 260 BIO *mem = BIO_new(BIO_s_mem()); 261 if (i2d_PUBKEY_bio(mem, k) <= 0) { 262 ERR_print_errors_fp(stderr); 263 return NULL; 264 } 265 p = (unsigned char *)OPENSSL_malloc(4096); 266 sz = BIO_read(mem, p, 4096); 267 268 /* Create the extension */ 269 ex = ext_new(nid, crit, p, sz); 270 271 /* Clean up */ 272 BIO_free(mem); 273 OPENSSL_free(p); 274 275 return ex; 276 } 277 278 ext_t *ext_get_by_opt(const char *opt) 279 { 280 ext_t *ext; 281 unsigned int i; 282 283 /* Sequential search. This is not a performance concern since the number 284 * of extensions is bounded and the code runs on a host machine */ 285 for (i = 0; i < num_extensions; i++) { 286 ext = &extensions[i]; 287 if (ext->opt && !strcmp(ext->opt, opt)) { 288 return ext; 289 } 290 } 291 292 return NULL; 293 } 294