crypto/cmp/cmp_util.c

   1 /*
   2  * Copyright 2007-2019 The OpenSSL Project Authors. All Rights Reserved.
   3  * Copyright Nokia 2007-2019
   4  * Copyright Siemens AG 2015-2019
   5  *
   6  * Licensed under the Apache License 2.0 (the "License").  You may not use
   7  * this file except in compliance with the License.  You can obtain a copy
   8  * in the file LICENSE in the source distribution or at
   9  * https://www.openssl.org/source/license.html
  10  */
  11
  12 #include <string.h>
  13 #include <openssl/cmp_util.h>
  14 #include "cmp_local.h" /* just for decls of internal functions defined here */
  15 #include <openssl/cmperr.h>
  16 #include <openssl/err.h> /* should be implied by cmperr.h */
  17 #include <openssl/x509v3.h>
  18
  19 /*
  20  * use trace API for CMP-specific logging, prefixed by "CMP " and severity
  21  */
  22
  23 int OSSL_CMP_log_open(void) /* is designed to be idempotent */
  24 {
  25 #ifndef OPENSSL_NO_STDIO
  26     BIO *bio = BIO_new_fp(stdout, BIO_NOCLOSE);
  27
  28     if (bio != NULL && OSSL_trace_set_channel(OSSL_TRACE_CATEGORY_CMP, bio))
  29         return 1;
  30     BIO_free(bio);
  31 #endif
  32     CMPerr(0, CMP_R_NO_STDIO);
  33     return 0;
  34 }
  35
  36 void OSSL_CMP_log_close(void) /* is designed to be idempotent */
  37 {
  38     (void)OSSL_trace_set_channel(OSSL_TRACE_CATEGORY_CMP, NULL);
  39 }
  40
  41 /* return >= 0 if level contains logging level, possibly preceded by "CMP " */
  42 #define max_level_len 5 /* = max length of the below strings, e.g., "EMERG" */
  43 static OSSL_CMP_severity parse_level(const char *level)
  44 {
  45     const char *end_level = strchr(level, ':');
  46     int len;
  47     char level_copy[max_level_len + 1];
  48
  49     if (end_level == NULL)
  50         return -1;
  51
  52     if (strncmp(level, OSSL_CMP_LOG_PREFIX,
  53                 strlen(OSSL_CMP_LOG_PREFIX)) == 0)
  54         level += strlen(OSSL_CMP_LOG_PREFIX);
  55     len = end_level - level;
  56     if (len > max_level_len)
  57         return -1;
  58     OPENSSL_strlcpy(level_copy, level, len + 1);
  59     return
  60         strcmp(level_copy, "EMERG") == 0 ? OSSL_CMP_LOG_EMERG :
  61         strcmp(level_copy, "ALERT") == 0 ? OSSL_CMP_LOG_ALERT :
  62         strcmp(level_copy, "CRIT") == 0 ? OSSL_CMP_LOG_CRIT :
  63         strcmp(level_copy, "ERROR") == 0 ? OSSL_CMP_LOG_ERR :
  64         strcmp(level_copy, "WARN") == 0 ? OSSL_CMP_LOG_WARNING :
  65         strcmp(level_copy, "NOTE") == 0 ? OSSL_CMP_LOG_NOTICE :
  66         strcmp(level_copy, "INFO") == 0 ? OSSL_CMP_LOG_INFO :
  67         strcmp(level_copy, "DEBUG") == 0 ? OSSL_CMP_LOG_DEBUG :
  68         -1;
  69 }
  70
  71 const char *ossl_cmp_log_parse_metadata(const char *buf,
  72                                         OSSL_CMP_severity *level,
  73                                         char **func, char **file, int *line)
  74 {
  75     const char *p_func = buf;
  76     const char *p_file = buf == NULL ? NULL : strchr(buf, ':');
  77     const char *p_level = buf;
  78     const char *msg = buf;
  79
  80     *level = -1;
  81     *func = NULL;
  82     *file = NULL;
  83     *line = 0;
  84
  85     if (p_file != NULL) {
  86         const char *p_line = strchr(++p_file, ':');
  87
  88         if ((*level = parse_level(buf)) < 0 && p_line != NULL) {
  89             /* check if buf contains location info and logging level */
  90             char *p_level_tmp = (char *)p_level;
  91             const long line_number = strtol(++p_line, &p_level_tmp, 10);
  92
  93             p_level = p_level_tmp;
  94             if (p_level > p_line && *(p_level++) == ':') {
  95                 if ((*level = parse_level(p_level)) >= 0) {
  96                     *func = OPENSSL_strndup(p_func, p_file - 1 - p_func);
  97                     *file = OPENSSL_strndup(p_file, p_line - 1 - p_file);
  98                     /* no real problem if OPENSSL_strndup() returns NULL */
  99                     *line = (int)line_number;
 100                     msg = strchr(p_level, ':') + 1;
 101                     if (*msg == ' ')
 102                         msg++;
 103                 }
 104             }
 105         }
 106     }
 107     return msg;
 108 }
 109
 110 #define UNKNOWN_FUNC "(unknown function)" /* the default for OPENSSL_FUNC */
 111 /*
 112  * substitute fallback if component/function name is NULL or empty or contains
 113  * just pseudo-information "(unknown function)" due to -pedantic and macros.h
 114  */
 115 static const char *improve_location_name(const char *func, const char *fallback)
 116 {
 117     if (!ossl_assert(fallback != NULL))
 118         return NULL;
 119     return func == NULL || *func == '\0' || strcmp(func, UNKNOWN_FUNC) == 0
 120         ? fallback : func;
 121 }
 122
 123 int OSSL_CMP_print_to_bio(BIO *bio, const char *component, const char *file,
 124                           int line, OSSL_CMP_severity level, const char *msg)
 125 {
 126     const char *level_string =
 127         level == OSSL_CMP_LOG_EMERG ? "EMERG" :
 128         level == OSSL_CMP_LOG_ALERT ? "ALERT" :
 129         level == OSSL_CMP_LOG_CRIT ? "CRIT" :
 130         level == OSSL_CMP_LOG_ERR ? "error" :
 131         level == OSSL_CMP_LOG_WARNING ? "warning" :
 132         level == OSSL_CMP_LOG_NOTICE ? "NOTE" :
 133         level == OSSL_CMP_LOG_INFO ? "info" :
 134         level == OSSL_CMP_LOG_DEBUG ? "DEBUG" : "(unknown level)";
 135
 136 #ifndef NDEBUG
 137     if (BIO_printf(bio, "%s:%s:%d:", improve_location_name(component, "CMP"),
 138                    file, line) < 0)
 139         return 0;
 140 #endif
 141     return BIO_printf(bio, OSSL_CMP_LOG_PREFIX"%s: %s\n",
 142                       level_string, msg) >= 0;
 143 }
 144
 145 #define ERR_PRINT_BUF_SIZE 4096
 146 /* this is similar to ERR_print_errors_cb, but uses the CMP-specific cb type */
 147 void OSSL_CMP_print_errors_cb(OSSL_cmp_log_cb_t log_fn)
 148 {
 149     unsigned long err;
 150     char msg[ERR_PRINT_BUF_SIZE];
 151     const char *file = NULL, *func = NULL, *data = NULL;
 152     int line, flags;
 153
 154     while ((err = ERR_get_error_all(&file, &line, &func, &data, &flags)) != 0) {
 155         const char *component =
 156             improve_location_name(func, ERR_lib_error_string(err));
 157
 158         if (!(flags & ERR_TXT_STRING))
 159             data = NULL;
 160         BIO_snprintf(msg, sizeof(msg), "%s%s%s", ERR_reason_error_string(err),
 161                      data == NULL || *data == '\0' ? "" : " : ",
 162                      data == NULL ? "" : data);
 163         if (log_fn == NULL) {
 164 #ifndef OPENSSL_NO_STDIO
 165             BIO *bio = BIO_new_fp(stderr, BIO_NOCLOSE);
 166
 167             if (bio != NULL) {
 168                 OSSL_CMP_print_to_bio(bio, component, file, line,
 169                                       OSSL_CMP_LOG_ERR, msg);
 170                 BIO_free(bio);
 171             }
 172 #else
 173             /* CMPerr(0, CMP_R_NO_STDIO) makes no sense during error printing */
 174 #endif
 175         } else {
 176             if (log_fn(component, file, line, OSSL_CMP_LOG_ERR, msg) <= 0)
 177                 break; /* abort outputting the error report */
 178         }
 179     }
 180 }
 181
 182 /*
 183  * functions manipulating lists of certificates etc.
 184  * these functions could be generally useful.
 185  */
 186
 187 int ossl_cmp_sk_X509_add1_cert(STACK_OF(X509) *sk, X509 *cert,
 188                                int no_dup, int prepend)
 189 {
 190     if (sk == NULL) {
 191         CMPerr(0, CMP_R_NULL_ARGUMENT);
 192         return 0;
 193     }
 194     if (no_dup) {
 195         /*
 196          * not using sk_X509_set_cmp_func() and sk_X509_find()
 197          * because this re-orders the certs on the stack
 198          */
 199         int i;
 200
 201         for (i = 0; i < sk_X509_num(sk); i++) {
 202             if (X509_cmp(sk_X509_value(sk, i), cert) == 0)
 203                 return 1;
 204         }
 205     }
 206     if (!X509_up_ref(cert))
 207         return 0;
 208     if (!sk_X509_insert(sk, cert, prepend ? 0 : -1)) {
 209         X509_free(cert);
 210         return 0;
 211     }
 212     return 1;
 213 }
 214
 215 int ossl_cmp_sk_X509_add1_certs(STACK_OF(X509) *sk, STACK_OF(X509) *certs,
 216                                 int no_self_issued, int no_dups, int prepend)
 217 /* compiler would allow 'const' for the list of certs, yet they are up-ref'ed */
 218 {
 219     int i;
 220
 221     if (sk == NULL) {
 222         CMPerr(0, CMP_R_NULL_ARGUMENT);
 223         return 0;
 224     }
 225     for (i = 0; i < sk_X509_num(certs); i++) { /* certs may be NULL */
 226         X509 *cert = sk_X509_value(certs, i);
 227
 228         if (!no_self_issued || X509_check_issued(cert, cert) != X509_V_OK) {
 229             if (!ossl_cmp_sk_X509_add1_cert(sk, cert, no_dups, prepend))
 230                 return 0;
 231         }
 232     }
 233     return 1;
 234 }
 235
 236 int ossl_cmp_X509_STORE_add1_certs(X509_STORE *store, STACK_OF(X509) *certs,
 237                                    int only_self_issued)
 238 {
 239     int i;
 240
 241     if (store == NULL) {
 242         CMPerr(0, CMP_R_NULL_ARGUMENT);
 243         return 0;
 244     }
 245     if (certs == NULL)
 246         return 1;
 247     for (i = 0; i < sk_X509_num(certs); i++) {
 248         X509 *cert = sk_X509_value(certs, i);
 249
 250         if (!only_self_issued || X509_check_issued(cert, cert) == X509_V_OK)
 251             if (!X509_STORE_add_cert(store, cert)) /* ups cert ref counter */
 252                 return 0;
 253     }
 254     return 1;
 255 }
 256
 257 /*-
 258  * Builds up the certificate chain of certs as high up as possible using
 259  * the given list of certs containing all possible intermediate certificates and
 260  * optionally the (possible) trust anchor(s). See also ssl_add_cert_chain().
 261  *
 262  * Intended use of this function is to find all the certificates above the trust
 263  * anchor needed to verify an EE's own certificate.  Those are supposed to be
 264  * included in the ExtraCerts field of every first sent message of a transaction
 265  * when MSG_SIG_ALG is utilized.
 266  *
 267  * NOTE: This allocates a stack and increments the reference count of each cert,
 268  * so when not needed any more the stack and all its elements should be freed.
 269  * NOTE: in case there is more than one possibility for the chain,
 270  * OpenSSL seems to take the first one, check X509_verify_cert() for details.
 271  *
 272  * returns a pointer to a stack of (up_ref'ed) X509 certificates containing:
 273  *      - the EE certificate given in the function arguments (cert)
 274  *      - all intermediate certificates up the chain toward the trust anchor
 275  *        whereas the (self-signed) trust anchor is not included
 276  * returns NULL on error
 277  */
 278 STACK_OF(X509) *ossl_cmp_build_cert_chain(STACK_OF(X509) *certs, X509 *cert)
 279 {
 280     STACK_OF(X509) *chain = NULL, *result = NULL;
 281     X509_STORE *store = X509_STORE_new();
 282     X509_STORE_CTX *csc = NULL;
 283
 284     if (certs == NULL || cert == NULL || store == NULL) {
 285         CMPerr(0, CMP_R_NULL_ARGUMENT);
 286         goto err;
 287     }
 288
 289     csc = X509_STORE_CTX_new();
 290     if (csc == NULL)
 291         goto err;
 292
 293     if (!ossl_cmp_X509_STORE_add1_certs(store, certs, 0)
 294             || !X509_STORE_CTX_init(csc, store, cert, NULL))
 295         goto err;
 296
 297     (void)ERR_set_mark();
 298     /*
 299      * ignore return value as it would fail without trust anchor given in store
 300      */
 301     (void)X509_verify_cert(csc);
 302
 303     /* don't leave any new errors in the queue */
 304     (void)ERR_pop_to_mark();
 305
 306     chain = X509_STORE_CTX_get0_chain(csc);
 307
 308     /* result list to store the up_ref'ed not self-issued certificates */
 309     if ((result = sk_X509_new_null()) == NULL)
 310         goto err;
 311     if (!ossl_cmp_sk_X509_add1_certs(result, chain, 1 /* no self-issued */,
 312                                      1 /* no duplicates */, 0)) {
 313         sk_X509_free(result);
 314         result = NULL;
 315     }
 316
 317  err:
 318     X509_STORE_free(store);
 319     X509_STORE_CTX_free(csc);
 320     return result;
 321 }
 322
 323 int ossl_cmp_sk_ASN1_UTF8STRING_push_str(STACK_OF(ASN1_UTF8STRING) *sk,
 324                                          const char *text)
 325 {
 326     ASN1_UTF8STRING *utf8string;
 327
 328     if (!ossl_assert(sk != NULL && text != NULL))
 329         return 0;
 330     if ((utf8string = ASN1_UTF8STRING_new()) == NULL)
 331         return 0;
 332     if (!ASN1_STRING_set(utf8string, text, -1))
 333         goto err;
 334     if (!sk_ASN1_UTF8STRING_push(sk, utf8string))
 335         goto err;
 336     return 1;
 337
 338  err:
 339     ASN1_UTF8STRING_free(utf8string);
 340     return 0;
 341 }
 342
 343 int ossl_cmp_asn1_octet_string_set1(ASN1_OCTET_STRING **tgt,
 344                                     const ASN1_OCTET_STRING *src)
 345 {
 346     ASN1_OCTET_STRING *new;
 347     if (tgt == NULL) {
 348         CMPerr(0, CMP_R_NULL_ARGUMENT);
 349         return 0;
 350     }
 351     if (*tgt == src) /* self-assignment */
 352         return 1;
 353
 354     if (src != NULL) {
 355         if ((new = ASN1_OCTET_STRING_dup(src)) == NULL)
 356             return 0;
 357     } else {
 358         new = NULL;
 359     }
 360
 361     ASN1_OCTET_STRING_free(*tgt);
 362     *tgt = new;
 363     return 1;
 364 }
 365
 366 int ossl_cmp_asn1_octet_string_set1_bytes(ASN1_OCTET_STRING **tgt,
 367                                           const unsigned char *bytes, int len)
 368 {
 369     ASN1_OCTET_STRING *new = NULL;
 370
 371     if (tgt == NULL) {
 372         CMPerr(0, CMP_R_NULL_ARGUMENT);
 373         return 0;
 374     }
 375     if (bytes != NULL) {
 376         if ((new = ASN1_OCTET_STRING_new()) == NULL
 377                 || !(ASN1_OCTET_STRING_set(new, bytes, len))) {
 378             ASN1_OCTET_STRING_free(new);
 379             return 0;
 380         }
 381     }
 382
 383     ASN1_OCTET_STRING_free(*tgt);
 384     *tgt = new;
 385     return 1;
 386 }
 387
 388 /*
 389  * calculate a digest of the given certificate,
 390  * using the same hash algorithm as in the certificate signature.
 391  */
 392 ASN1_OCTET_STRING *OSSL_CMP_X509_digest(const X509 *cert)
 393 {
 394     unsigned int len;
 395     unsigned char hash[EVP_MAX_MD_SIZE];
 396     int md_NID;
 397     const EVP_MD *md = NULL;
 398     ASN1_OCTET_STRING *new = NULL;
 399
 400     if (!ossl_assert(cert != NULL))
 401         return NULL;
 402
 403     /*-
 404      * select hash algorithm, as stated in CMP RFC 4210 Appendix F.
 405      * Compilable ASN.1 defs:
 406      * the hash of the certificate, using the same hash algorithm
 407      * as is used to create and verify the certificate signature
 408      */
 409     if (!OBJ_find_sigid_algs(X509_get_signature_nid(cert), &md_NID, NULL)
 410             || (md = EVP_get_digestbynid(md_NID)) == NULL) {
 411         CMPerr(0, CMP_R_UNSUPPORTED_ALGORITHM);
 412         return NULL;
 413     }
 414     if (!X509_digest(cert, md, hash, &len)
 415             || (new = ASN1_OCTET_STRING_new()) == NULL)
 416         return NULL;
 417     if (!(ASN1_OCTET_STRING_set(new, hash, len))) {
 418         ASN1_OCTET_STRING_free(new);
 419         return NULL;
 420     }
 421     return new;
 422 }