xref: /freebsd/crypto/openssl/crypto/cmp/cmp_client.c (revision aa1a8ff2d6dbc51ef058f46f3db5a8bb77967145)
1 /*
2  * Copyright 2007-2023 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 "cmp_local.h"
13 #include "internal/cryptlib.h"
14 #include "e_os.h" /* ossl_sleep() */
15 
16 /* explicit #includes not strictly needed since implied by the above: */
17 #include <openssl/bio.h>
18 #include <openssl/cmp.h>
19 #include <openssl/err.h>
20 #include <openssl/evp.h>
21 #include <openssl/x509v3.h>
22 #include <openssl/cmp_util.h>
23 
24 #define IS_CREP(t) ((t) == OSSL_CMP_PKIBODY_IP || (t) == OSSL_CMP_PKIBODY_CP \
25                         || (t) == OSSL_CMP_PKIBODY_KUP)
26 
27 /*-
28  * Evaluate whether there's an exception (violating the standard) configured for
29  * handling negative responses without protection or with invalid protection.
30  * Returns 1 on acceptance, 0 on rejection, or -1 on (internal) error.
31  */
32 static int unprotected_exception(const OSSL_CMP_CTX *ctx,
33                                  const OSSL_CMP_MSG *rep,
34                                  int invalid_protection,
35                                  int expected_type /* ignored here */)
36 {
37     int rcvd_type = OSSL_CMP_MSG_get_bodytype(rep /* may be NULL */);
38     const char *msg_type = NULL;
39 
40     if (!ossl_assert(ctx != NULL && rep != NULL))
41         return -1;
42 
43     if (!ctx->unprotectedErrors)
44         return 0;
45 
46     switch (rcvd_type) {
47     case OSSL_CMP_PKIBODY_ERROR:
48         msg_type = "error response";
49         break;
50     case OSSL_CMP_PKIBODY_RP:
51         {
52             OSSL_CMP_PKISI *si =
53                 ossl_cmp_revrepcontent_get_pkisi(rep->body->value.rp,
54                                                  OSSL_CMP_REVREQSID);
55 
56             if (si == NULL)
57                 return -1;
58             if (ossl_cmp_pkisi_get_status(si) == OSSL_CMP_PKISTATUS_rejection)
59                 msg_type = "revocation response message with rejection status";
60             break;
61         }
62     case OSSL_CMP_PKIBODY_PKICONF:
63         msg_type = "PKI Confirmation message";
64         break;
65     default:
66         if (IS_CREP(rcvd_type)) {
67             int any_rid = OSSL_CMP_CERTREQID_NONE;
68             OSSL_CMP_CERTREPMESSAGE *crepmsg = rep->body->value.ip;
69             OSSL_CMP_CERTRESPONSE *crep =
70                 ossl_cmp_certrepmessage_get0_certresponse(crepmsg, any_rid);
71 
72             if (sk_OSSL_CMP_CERTRESPONSE_num(crepmsg->response) > 1)
73                 return -1;
74             if (crep == NULL)
75                 return -1;
76             if (ossl_cmp_pkisi_get_status(crep->status)
77                 == OSSL_CMP_PKISTATUS_rejection)
78                 msg_type = "CertRepMessage with rejection status";
79         }
80     }
81     if (msg_type == NULL)
82         return 0;
83     ossl_cmp_log2(WARN, ctx, "ignoring %s protection of %s",
84                   invalid_protection ? "invalid" : "missing", msg_type);
85     return 1;
86 }
87 
88 /* Save error info from PKIStatusInfo field of a certresponse into ctx */
89 static int save_statusInfo(OSSL_CMP_CTX *ctx, OSSL_CMP_PKISI *si)
90 {
91     int i;
92     OSSL_CMP_PKIFREETEXT *ss;
93 
94     if (!ossl_assert(ctx != NULL && si != NULL))
95         return 0;
96 
97     ctx->status = ossl_cmp_pkisi_get_status(si);
98     if (ctx->status < OSSL_CMP_PKISTATUS_accepted)
99         return 0;
100 
101     ctx->failInfoCode = ossl_cmp_pkisi_get_pkifailureinfo(si);
102 
103     if (!ossl_cmp_ctx_set0_statusString(ctx, sk_ASN1_UTF8STRING_new_null())
104             || (ctx->statusString == NULL))
105         return 0;
106 
107     ss = si->statusString; /* may be NULL */
108     for (i = 0; i < sk_ASN1_UTF8STRING_num(ss); i++) {
109         ASN1_UTF8STRING *str = sk_ASN1_UTF8STRING_value(ss, i);
110 
111         if (!sk_ASN1_UTF8STRING_push(ctx->statusString, ASN1_STRING_dup(str)))
112             return 0;
113     }
114     return 1;
115 }
116 
117 /*-
118  * Perform the generic aspects of sending a request and receiving a response.
119  * Returns 1 on success and provides the received PKIMESSAGE in *rep.
120  * Returns 0 on error.
121  * Regardless of success, caller is responsible for freeing *rep (unless NULL).
122  */
123 static int send_receive_check(OSSL_CMP_CTX *ctx, const OSSL_CMP_MSG *req,
124                               OSSL_CMP_MSG **rep, int expected_type)
125 {
126     int begin_transaction =
127         expected_type != OSSL_CMP_PKIBODY_POLLREP
128         && expected_type != OSSL_CMP_PKIBODY_PKICONF;
129     const char *req_type_str =
130         ossl_cmp_bodytype_to_string(OSSL_CMP_MSG_get_bodytype(req));
131     const char *expected_type_str = ossl_cmp_bodytype_to_string(expected_type);
132     int bak_msg_timeout = ctx->msg_timeout;
133     int bt;
134     time_t now = time(NULL);
135     int time_left;
136     OSSL_CMP_transfer_cb_t transfer_cb = ctx->transfer_cb;
137 
138     if (transfer_cb == NULL)
139         transfer_cb = OSSL_CMP_MSG_http_perform;
140     *rep = NULL;
141 
142     if (ctx->total_timeout != 0 /* not waiting indefinitely */) {
143         if (begin_transaction)
144             ctx->end_time = now + ctx->total_timeout;
145         if (now >= ctx->end_time) {
146             ERR_raise(ERR_LIB_CMP, CMP_R_TOTAL_TIMEOUT);
147             return 0;
148         }
149         if (!ossl_assert(ctx->end_time - now < INT_MAX)) {
150             /* actually cannot happen due to assignment in initial_certreq() */
151             ERR_raise(ERR_LIB_CMP, CMP_R_INVALID_ARGS);
152             return 0;
153         }
154         time_left = (int)(ctx->end_time - now);
155         if (ctx->msg_timeout == 0 || time_left < ctx->msg_timeout)
156             ctx->msg_timeout = time_left;
157     }
158 
159     /* should print error queue since transfer_cb may call ERR_clear_error() */
160     OSSL_CMP_CTX_print_errors(ctx);
161 
162     ossl_cmp_log1(INFO, ctx, "sending %s", req_type_str);
163 
164     *rep = (*transfer_cb)(ctx, req);
165     ctx->msg_timeout = bak_msg_timeout;
166 
167     if (*rep == NULL) {
168         ERR_raise_data(ERR_LIB_CMP,
169                        ctx->total_timeout != 0 && time(NULL) >= ctx->end_time ?
170                        CMP_R_TOTAL_TIMEOUT : CMP_R_TRANSFER_ERROR,
171                        "request sent: %s, expected response: %s",
172                        req_type_str, expected_type_str);
173         return 0;
174     }
175 
176     bt = OSSL_CMP_MSG_get_bodytype(*rep);
177     /*
178      * The body type in the 'bt' variable is not yet verified.
179      * Still we use this preliminary value already for a progress report because
180      * the following msg verification may also produce log entries and may fail.
181      */
182     ossl_cmp_log1(INFO, ctx, "received %s", ossl_cmp_bodytype_to_string(bt));
183 
184     /* copy received extraCerts to ctx->extraCertsIn so they can be retrieved */
185     if (bt != OSSL_CMP_PKIBODY_POLLREP && bt != OSSL_CMP_PKIBODY_PKICONF
186             && !ossl_cmp_ctx_set1_extraCertsIn(ctx, (*rep)->extraCerts))
187         return 0;
188 
189     if (!ossl_cmp_msg_check_update(ctx, *rep, unprotected_exception,
190                                    expected_type))
191         return 0;
192 
193     if (bt == expected_type
194         /* as an answer to polling, there could be IP/CP/KUP: */
195             || (IS_CREP(bt) && expected_type == OSSL_CMP_PKIBODY_POLLREP))
196         return 1;
197 
198     /* received message type is not one of the expected ones (e.g., error) */
199     ERR_raise(ERR_LIB_CMP, bt == OSSL_CMP_PKIBODY_ERROR ? CMP_R_RECEIVED_ERROR :
200               CMP_R_UNEXPECTED_PKIBODY); /* in next line for mkerr.pl */
201 
202     if (bt != OSSL_CMP_PKIBODY_ERROR) {
203         ERR_add_error_data(3, "message type is '",
204                            ossl_cmp_bodytype_to_string(bt), "'");
205     } else {
206         OSSL_CMP_ERRORMSGCONTENT *emc = (*rep)->body->value.error;
207         OSSL_CMP_PKISI *si = emc->pKIStatusInfo;
208         char buf[OSSL_CMP_PKISI_BUFLEN];
209 
210         if (save_statusInfo(ctx, si)
211                 && OSSL_CMP_CTX_snprint_PKIStatus(ctx, buf,
212                                                   sizeof(buf)) != NULL)
213             ERR_add_error_data(1, buf);
214         if (emc->errorCode != NULL
215                 && BIO_snprintf(buf, sizeof(buf), "; errorCode: %08lX",
216                                 ASN1_INTEGER_get(emc->errorCode)) > 0)
217             ERR_add_error_data(1, buf);
218         if (emc->errorDetails != NULL) {
219             char *text = ossl_sk_ASN1_UTF8STRING2text(emc->errorDetails, ", ",
220                                                       OSSL_CMP_PKISI_BUFLEN - 1);
221 
222             if (text != NULL && *text != '\0')
223                 ERR_add_error_data(2, "; errorDetails: ", text);
224             OPENSSL_free(text);
225         }
226         if (ctx->status != OSSL_CMP_PKISTATUS_rejection) {
227             ERR_raise(ERR_LIB_CMP, CMP_R_UNEXPECTED_PKISTATUS);
228             if (ctx->status == OSSL_CMP_PKISTATUS_waiting)
229                 ctx->status = OSSL_CMP_PKISTATUS_rejection;
230         }
231     }
232     return 0;
233 }
234 
235 /*-
236  * When a 'waiting' PKIStatus has been received, this function is used to
237  * poll, which should yield a pollRep or finally a CertRepMessage in ip/cp/kup.
238  * On receiving a pollRep, which includes a checkAfter value, it return this
239  * value if sleep == 0, else it sleeps as long as indicated and retries.
240  *
241  * A transaction timeout is enabled if ctx->total_timeout is != 0.
242  * In this case polling will continue until the timeout is reached and then
243  * polling is done a last time even if this is before the "checkAfter" time.
244  *
245  * Returns -1 on receiving pollRep if sleep == 0, setting the checkAfter value.
246  * Returns 1 on success and provides the received PKIMESSAGE in *rep.
247  *           In this case the caller is responsible for freeing *rep.
248  * Returns 0 on error (which includes the case that timeout has been reached).
249  */
250 static int poll_for_response(OSSL_CMP_CTX *ctx, int sleep, int rid,
251                              OSSL_CMP_MSG **rep, int *checkAfter)
252 {
253     OSSL_CMP_MSG *preq = NULL;
254     OSSL_CMP_MSG *prep = NULL;
255 
256     ossl_cmp_info(ctx,
257                   "received 'waiting' PKIStatus, starting to poll for response");
258     *rep = NULL;
259     for (;;) {
260         if ((preq = ossl_cmp_pollReq_new(ctx, rid)) == NULL)
261             goto err;
262 
263         if (!send_receive_check(ctx, preq, &prep, OSSL_CMP_PKIBODY_POLLREP))
264             goto err;
265 
266         /* handle potential pollRep */
267         if (OSSL_CMP_MSG_get_bodytype(prep) == OSSL_CMP_PKIBODY_POLLREP) {
268             OSSL_CMP_POLLREPCONTENT *prc = prep->body->value.pollRep;
269             OSSL_CMP_POLLREP *pollRep = NULL;
270             int64_t check_after;
271             char str[OSSL_CMP_PKISI_BUFLEN];
272             int len;
273 
274             if (sk_OSSL_CMP_POLLREP_num(prc) > 1) {
275                 ERR_raise(ERR_LIB_CMP, CMP_R_MULTIPLE_RESPONSES_NOT_SUPPORTED);
276                 goto err;
277             }
278             pollRep = ossl_cmp_pollrepcontent_get0_pollrep(prc, rid);
279             if (pollRep == NULL)
280                 goto err;
281 
282             if (!ASN1_INTEGER_get_int64(&check_after, pollRep->checkAfter)) {
283                 ERR_raise(ERR_LIB_CMP, CMP_R_BAD_CHECKAFTER_IN_POLLREP);
284                 goto err;
285             }
286             if (check_after < 0 || (uint64_t)check_after
287                 > (sleep ? ULONG_MAX / 1000 : INT_MAX)) {
288                 ERR_raise(ERR_LIB_CMP, CMP_R_CHECKAFTER_OUT_OF_RANGE);
289                 if (BIO_snprintf(str, OSSL_CMP_PKISI_BUFLEN, "value = %jd",
290                                  check_after) >= 0)
291                     ERR_add_error_data(1, str);
292                 goto err;
293             }
294 
295             if (pollRep->reason == NULL
296                     || (len = BIO_snprintf(str, OSSL_CMP_PKISI_BUFLEN,
297                                            " with reason = '")) < 0) {
298                 *str = '\0';
299             } else {
300                 char *text = ossl_sk_ASN1_UTF8STRING2text(pollRep->reason, ", ",
301                                                           sizeof(str) - len - 2);
302 
303                 if (text == NULL
304                         || BIO_snprintf(str + len, sizeof(str) - len,
305                                         "%s'", text) < 0)
306                     *str = '\0';
307                 OPENSSL_free(text);
308             }
309             ossl_cmp_log2(INFO, ctx,
310                           "received polling response%s; checkAfter = %ld seconds",
311                           str, check_after);
312 
313             if (ctx->total_timeout != 0) { /* timeout is not infinite */
314                 const int exp = 5; /* expected max time per msg round trip */
315                 int64_t time_left = (int64_t)(ctx->end_time - exp - time(NULL));
316 
317                 if (time_left <= 0) {
318                     ERR_raise(ERR_LIB_CMP, CMP_R_TOTAL_TIMEOUT);
319                     goto err;
320                 }
321                 if (time_left < check_after)
322                     check_after = time_left;
323                 /* poll one last time just when timeout was reached */
324             }
325 
326             OSSL_CMP_MSG_free(preq);
327             preq = NULL;
328             OSSL_CMP_MSG_free(prep);
329             prep = NULL;
330             if (sleep) {
331                 ossl_sleep((unsigned long)(1000 * check_after));
332             } else {
333                 if (checkAfter != NULL)
334                     *checkAfter = (int)check_after;
335                 return -1; /* exits the loop */
336             }
337         } else {
338             ossl_cmp_info(ctx, "received ip/cp/kup after polling");
339             /* any other body type has been rejected by send_receive_check() */
340             break;
341         }
342     }
343     if (prep == NULL)
344         goto err;
345 
346     OSSL_CMP_MSG_free(preq);
347     *rep = prep;
348 
349     return 1;
350  err:
351     OSSL_CMP_MSG_free(preq);
352     OSSL_CMP_MSG_free(prep);
353     return 0;
354 }
355 
356 /*
357  * Send certConf for IR, CR or KUR sequences and check response,
358  * not modifying ctx->status during the certConf exchange
359  */
360 int ossl_cmp_exchange_certConf(OSSL_CMP_CTX *ctx, int certReqId,
361                                int fail_info, const char *txt)
362 {
363     OSSL_CMP_MSG *certConf;
364     OSSL_CMP_MSG *PKIconf = NULL;
365     int res = 0;
366 
367     /* OSSL_CMP_certConf_new() also checks if all necessary options are set */
368     certConf = ossl_cmp_certConf_new(ctx, certReqId, fail_info, txt);
369     if (certConf == NULL)
370         goto err;
371 
372     res = send_receive_check(ctx, certConf, &PKIconf, OSSL_CMP_PKIBODY_PKICONF);
373 
374  err:
375     OSSL_CMP_MSG_free(certConf);
376     OSSL_CMP_MSG_free(PKIconf);
377     return res;
378 }
379 
380 /* Send given error and check response */
381 int ossl_cmp_exchange_error(OSSL_CMP_CTX *ctx, int status, int fail_info,
382                             const char *txt, int errorCode, const char *details)
383 {
384     OSSL_CMP_MSG *error = NULL;
385     OSSL_CMP_PKISI *si = NULL;
386     OSSL_CMP_MSG *PKIconf = NULL;
387     int res = 0;
388 
389     /* not overwriting ctx->status on error exchange */
390     if ((si = OSSL_CMP_STATUSINFO_new(status, fail_info, txt)) == NULL)
391         goto err;
392     /* ossl_cmp_error_new() also checks if all necessary options are set */
393     if ((error = ossl_cmp_error_new(ctx, si, errorCode, details, 0)) == NULL)
394         goto err;
395 
396     res = send_receive_check(ctx, error, &PKIconf, OSSL_CMP_PKIBODY_PKICONF);
397 
398  err:
399     OSSL_CMP_MSG_free(error);
400     OSSL_CMP_PKISI_free(si);
401     OSSL_CMP_MSG_free(PKIconf);
402     return res;
403 }
404 
405 /*-
406  * Retrieve a copy of the certificate, if any, from the given CertResponse.
407  * Take into account PKIStatusInfo of CertResponse in ctx, report it on error.
408  * Returns NULL if not found or on error.
409  */
410 static X509 *get1_cert_status(OSSL_CMP_CTX *ctx, int bodytype,
411                               OSSL_CMP_CERTRESPONSE *crep)
412 {
413     char buf[OSSL_CMP_PKISI_BUFLEN];
414     X509 *crt = NULL;
415 
416     if (!ossl_assert(ctx != NULL && crep != NULL))
417         return NULL;
418 
419     switch (ossl_cmp_pkisi_get_status(crep->status)) {
420     case OSSL_CMP_PKISTATUS_waiting:
421         ossl_cmp_err(ctx,
422                      "received \"waiting\" status for cert when actually aiming to extract cert");
423         ERR_raise(ERR_LIB_CMP, CMP_R_ENCOUNTERED_WAITING);
424         goto err;
425     case OSSL_CMP_PKISTATUS_grantedWithMods:
426         ossl_cmp_warn(ctx, "received \"grantedWithMods\" for certificate");
427         break;
428     case OSSL_CMP_PKISTATUS_accepted:
429         break;
430         /* get all information in case of a rejection before going to error */
431     case OSSL_CMP_PKISTATUS_rejection:
432         ossl_cmp_err(ctx, "received \"rejection\" status rather than cert");
433         ERR_raise(ERR_LIB_CMP, CMP_R_REQUEST_REJECTED_BY_SERVER);
434         goto err;
435     case OSSL_CMP_PKISTATUS_revocationWarning:
436         ossl_cmp_warn(ctx,
437                       "received \"revocationWarning\" - a revocation of the cert is imminent");
438         break;
439     case OSSL_CMP_PKISTATUS_revocationNotification:
440         ossl_cmp_warn(ctx,
441                       "received \"revocationNotification\" - a revocation of the cert has occurred");
442         break;
443     case OSSL_CMP_PKISTATUS_keyUpdateWarning:
444         if (bodytype != OSSL_CMP_PKIBODY_KUR) {
445             ERR_raise(ERR_LIB_CMP, CMP_R_ENCOUNTERED_KEYUPDATEWARNING);
446             goto err;
447         }
448         break;
449     default:
450         ossl_cmp_log1(ERROR, ctx,
451                       "received unsupported PKIStatus %d for certificate",
452                       ctx->status);
453         ERR_raise(ERR_LIB_CMP, CMP_R_UNKNOWN_PKISTATUS);
454         goto err;
455     }
456     crt = ossl_cmp_certresponse_get1_cert(ctx, crep);
457     if (crt == NULL) /* according to PKIStatus, we can expect a cert */
458         ERR_raise(ERR_LIB_CMP, CMP_R_CERTIFICATE_NOT_FOUND);
459 
460     return crt;
461 
462  err:
463     if (OSSL_CMP_CTX_snprint_PKIStatus(ctx, buf, sizeof(buf)) != NULL)
464         ERR_add_error_data(1, buf);
465     return NULL;
466 }
467 
468 /*-
469  * Callback fn validating that the new certificate can be verified, using
470  * ctx->certConf_cb_arg, which has been initialized using opt_out_trusted, and
471  * ctx->untrusted, which at this point already contains msg->extraCerts.
472  * Returns 0 on acceptance, else a bit field reflecting PKIFailureInfo.
473  * Quoting from RFC 4210 section 5.1. Overall PKI Message:
474  *     The extraCerts field can contain certificates that may be useful to
475  *     the recipient.  For example, this can be used by a CA or RA to
476  *     present an end entity with certificates that it needs to verify its
477  *     own new certificate (if, for example, the CA that issued the end
478  *     entity's certificate is not a root CA for the end entity).  Note that
479  *     this field does not necessarily contain a certification path; the
480  *     recipient may have to sort, select from, or otherwise process the
481  *     extra certificates in order to use them.
482  * Note: While often handy, there is no hard requirement by CMP that
483  * an EE must be able to validate the certificates it gets enrolled.
484  */
485 int OSSL_CMP_certConf_cb(OSSL_CMP_CTX *ctx, X509 *cert, int fail_info,
486                          const char **text)
487 {
488     X509_STORE *out_trusted = OSSL_CMP_CTX_get_certConf_cb_arg(ctx);
489     STACK_OF(X509) *chain = NULL;
490     (void)text; /* make (artificial) use of var to prevent compiler warning */
491 
492     if (fail_info != 0) /* accept any error flagged by CMP core library */
493         return fail_info;
494 
495     if (out_trusted == NULL) {
496         ossl_cmp_debug(ctx, "trying to build chain for newly enrolled cert");
497         chain = X509_build_chain(cert, ctx->untrusted, out_trusted,
498                                  0, ctx->libctx, ctx->propq);
499     } else {
500         X509_STORE_CTX *csc = X509_STORE_CTX_new_ex(ctx->libctx, ctx->propq);
501 
502         ossl_cmp_debug(ctx, "validating newly enrolled cert");
503         if (csc == NULL)
504             goto err;
505         if (!X509_STORE_CTX_init(csc, out_trusted, cert, ctx->untrusted))
506             goto err;
507         /* disable any cert status/revocation checking etc. */
508         X509_VERIFY_PARAM_clear_flags(X509_STORE_CTX_get0_param(csc),
509                                       ~(X509_V_FLAG_USE_CHECK_TIME
510                                         | X509_V_FLAG_NO_CHECK_TIME
511                                         | X509_V_FLAG_PARTIAL_CHAIN
512                                         | X509_V_FLAG_POLICY_CHECK));
513         if (X509_verify_cert(csc) <= 0)
514             goto err;
515 
516         if (!ossl_x509_add_certs_new(&chain,  X509_STORE_CTX_get0_chain(csc),
517                                      X509_ADD_FLAG_UP_REF | X509_ADD_FLAG_NO_DUP
518                                      | X509_ADD_FLAG_NO_SS)) {
519             sk_X509_free(chain);
520             chain = NULL;
521         }
522     err:
523         X509_STORE_CTX_free(csc);
524     }
525 
526     if (sk_X509_num(chain) > 0)
527         X509_free(sk_X509_shift(chain)); /* remove leaf (EE) cert */
528     if (out_trusted != NULL) {
529         if (chain == NULL) {
530             ossl_cmp_err(ctx, "failed to validate newly enrolled cert");
531             fail_info = 1 << OSSL_CMP_PKIFAILUREINFO_incorrectData;
532         } else {
533             ossl_cmp_debug(ctx,
534                            "success validating newly enrolled cert");
535         }
536     } else if (chain == NULL) {
537         ossl_cmp_warn(ctx, "could not build approximate chain for newly enrolled cert, resorting to received extraCerts");
538         chain = OSSL_CMP_CTX_get1_extraCertsIn(ctx);
539     } else {
540         ossl_cmp_debug(ctx,
541                        "success building approximate chain for newly enrolled cert");
542     }
543     (void)ossl_cmp_ctx_set1_newChain(ctx, chain);
544     sk_X509_pop_free(chain, X509_free);
545 
546     return fail_info;
547 }
548 
549 /*-
550  * Perform the generic handling of certificate responses for IR/CR/KUR/P10CR.
551  * |rid| must be OSSL_CMP_CERTREQID_NONE if not available, namely for p10cr
552  * Returns -1 on receiving pollRep if sleep == 0, setting the checkAfter value.
553  * Returns 1 on success and provides the received PKIMESSAGE in *resp.
554  * Returns 0 on error (which includes the case that timeout has been reached).
555  * Regardless of success, caller is responsible for freeing *resp (unless NULL).
556  */
557 static int cert_response(OSSL_CMP_CTX *ctx, int sleep, int rid,
558                          OSSL_CMP_MSG **resp, int *checkAfter,
559                          int req_type, int expected_type)
560 {
561     EVP_PKEY *rkey = ossl_cmp_ctx_get0_newPubkey(ctx);
562     int fail_info = 0; /* no failure */
563     const char *txt = NULL;
564     OSSL_CMP_CERTREPMESSAGE *crepmsg;
565     OSSL_CMP_CERTRESPONSE *crep;
566     OSSL_CMP_certConf_cb_t cb;
567     X509 *cert;
568     char *subj = NULL;
569     int ret = 1;
570 
571     if (!ossl_assert(ctx != NULL))
572         return 0;
573 
574  retry:
575     crepmsg = (*resp)->body->value.ip; /* same for cp and kup */
576     if (sk_OSSL_CMP_CERTRESPONSE_num(crepmsg->response) > 1) {
577         ERR_raise(ERR_LIB_CMP, CMP_R_MULTIPLE_RESPONSES_NOT_SUPPORTED);
578         return 0;
579     }
580     crep = ossl_cmp_certrepmessage_get0_certresponse(crepmsg, rid);
581     if (crep == NULL)
582         return 0;
583     if (!save_statusInfo(ctx, crep->status))
584         return 0;
585     if (rid == OSSL_CMP_CERTREQID_NONE) { /* used for OSSL_CMP_PKIBODY_P10CR */
586         rid = ossl_cmp_asn1_get_int(crep->certReqId);
587         if (rid < OSSL_CMP_CERTREQID_NONE) {
588             ERR_raise(ERR_LIB_CMP, CMP_R_BAD_REQUEST_ID);
589             return 0;
590         }
591     }
592 
593     if (ossl_cmp_pkisi_get_status(crep->status) == OSSL_CMP_PKISTATUS_waiting) {
594         OSSL_CMP_MSG_free(*resp);
595         *resp = NULL;
596         if ((ret = poll_for_response(ctx, sleep, rid, resp, checkAfter)) != 0) {
597             if (ret == -1) /* at this point implies sleep == 0 */
598                 return ret; /* waiting */
599             goto retry; /* got ip/cp/kup, which may still indicate 'waiting' */
600         } else {
601             ERR_raise(ERR_LIB_CMP, CMP_R_POLLING_FAILED);
602             return 0;
603         }
604     }
605 
606     cert = get1_cert_status(ctx, (*resp)->body->type, crep);
607     if (cert == NULL) {
608         ERR_add_error_data(1, "; cannot extract certificate from response");
609         return 0;
610     }
611     if (!ossl_cmp_ctx_set0_newCert(ctx, cert))
612         return 0;
613 
614     /*
615      * if the CMP server returned certificates in the caPubs field, copy them
616      * to the context so that they can be retrieved if necessary
617      */
618     if (crepmsg->caPubs != NULL
619             && !ossl_cmp_ctx_set1_caPubs(ctx, crepmsg->caPubs))
620         return 0;
621 
622     subj = X509_NAME_oneline(X509_get_subject_name(cert), NULL, 0);
623     if (rkey != NULL
624         /* X509_check_private_key() also works if rkey is just public key */
625             && !(X509_check_private_key(ctx->newCert, rkey))) {
626         fail_info = 1 << OSSL_CMP_PKIFAILUREINFO_incorrectData;
627         txt = "public key in new certificate does not match our enrollment key";
628         /*-
629          * not calling (void)ossl_cmp_exchange_error(ctx,
630          *                   OSSL_CMP_PKISTATUS_rejection, fail_info, txt)
631          * not throwing CMP_R_CERTIFICATE_NOT_ACCEPTED with txt
632          * not returning 0
633          * since we better leave this for the certConf_cb to decide
634          */
635     }
636 
637     /*
638      * Execute the certification checking callback function,
639      * which can determine whether to accept a newly enrolled certificate.
640      * It may overrule the pre-decision reflected in 'fail_info' and '*txt'.
641      */
642     cb = ctx->certConf_cb != NULL ? ctx->certConf_cb : OSSL_CMP_certConf_cb;
643     if ((fail_info = cb(ctx, ctx->newCert, fail_info, &txt)) != 0
644             && txt == NULL)
645         txt = "CMP client did not accept it";
646     if (fail_info != 0) /* immediately log error before any certConf exchange */
647         ossl_cmp_log1(ERROR, ctx,
648                       "rejecting newly enrolled cert with subject: %s", subj);
649     if (!ctx->disableConfirm
650             && !ossl_cmp_hdr_has_implicitConfirm((*resp)->header)) {
651         if (!ossl_cmp_exchange_certConf(ctx, rid, fail_info, txt))
652             ret = 0;
653     }
654 
655     /* not throwing failure earlier as transfer_cb may call ERR_clear_error() */
656     if (fail_info != 0) {
657         ERR_raise_data(ERR_LIB_CMP, CMP_R_CERTIFICATE_NOT_ACCEPTED,
658                        "rejecting newly enrolled cert with subject: %s; %s",
659                        subj, txt);
660         ctx->status = OSSL_CMP_PKISTATUS_rejection;
661         ret = 0;
662     }
663     OPENSSL_free(subj);
664     return ret;
665 }
666 
667 static int initial_certreq(OSSL_CMP_CTX *ctx,
668                            int req_type, const OSSL_CRMF_MSG *crm,
669                            OSSL_CMP_MSG **p_rep, int rep_type)
670 {
671     OSSL_CMP_MSG *req;
672     int res;
673 
674     ctx->status = OSSL_CMP_PKISTATUS_request;
675     if (!ossl_cmp_ctx_set0_newCert(ctx, NULL))
676         return 0;
677 
678     /* also checks if all necessary options are set */
679     if ((req = ossl_cmp_certreq_new(ctx, req_type, crm)) == NULL)
680         return 0;
681 
682     ctx->status = OSSL_CMP_PKISTATUS_trans;
683     res = send_receive_check(ctx, req, p_rep, rep_type);
684     OSSL_CMP_MSG_free(req);
685     return res;
686 }
687 
688 int OSSL_CMP_try_certreq(OSSL_CMP_CTX *ctx, int req_type,
689                          const OSSL_CRMF_MSG *crm, int *checkAfter)
690 {
691     OSSL_CMP_MSG *rep = NULL;
692     int is_p10 = req_type == OSSL_CMP_PKIBODY_P10CR;
693     int rid = is_p10 ? OSSL_CMP_CERTREQID_NONE : OSSL_CMP_CERTREQID;
694     int rep_type = is_p10 ? OSSL_CMP_PKIBODY_CP : req_type + 1;
695     int res = 0;
696 
697     if (ctx == NULL) {
698         ERR_raise(ERR_LIB_CMP, CMP_R_NULL_ARGUMENT);
699         return 0;
700     }
701 
702     if (ctx->status != OSSL_CMP_PKISTATUS_waiting) { /* not polling already */
703         if (!initial_certreq(ctx, req_type, crm, &rep, rep_type))
704             goto err;
705     } else {
706         if (req_type < 0)
707             return ossl_cmp_exchange_error(ctx, OSSL_CMP_PKISTATUS_rejection,
708                                            0, "polling aborted",
709                                            0 /* errorCode */, "by application");
710         res = poll_for_response(ctx, 0 /* no sleep */, rid, &rep, checkAfter);
711         if (res <= 0) /* waiting or error */
712             return res;
713     }
714     res = cert_response(ctx, 0 /* no sleep */, rid, &rep, checkAfter,
715                         req_type, rep_type);
716 
717  err:
718     OSSL_CMP_MSG_free(rep);
719     return res;
720 }
721 
722 /*-
723  * Do the full sequence CR/IR/KUR/P10CR, CP/IP/KUP/CP,
724  * certConf, PKIconf, and polling if required.
725  * Will sleep as long as indicated by the server (according to checkAfter).
726  * All enrollment options need to be present in the context.
727  * Returns pointer to received certificate, or NULL if none was received.
728  */
729 X509 *OSSL_CMP_exec_certreq(OSSL_CMP_CTX *ctx, int req_type,
730                             const OSSL_CRMF_MSG *crm)
731 {
732 
733     OSSL_CMP_MSG *rep = NULL;
734     int is_p10 = req_type == OSSL_CMP_PKIBODY_P10CR;
735     int rid = is_p10 ? OSSL_CMP_CERTREQID_NONE : OSSL_CMP_CERTREQID;
736     int rep_type = is_p10 ? OSSL_CMP_PKIBODY_CP : req_type + 1;
737     X509 *result = NULL;
738 
739     if (ctx == NULL) {
740         ERR_raise(ERR_LIB_CMP, CMP_R_NULL_ARGUMENT);
741         return NULL;
742     }
743 
744     if (!initial_certreq(ctx, req_type, crm, &rep, rep_type))
745         goto err;
746 
747     if (cert_response(ctx, 1 /* sleep */, rid, &rep, NULL, req_type, rep_type)
748         <= 0)
749         goto err;
750 
751     result = ctx->newCert;
752  err:
753     OSSL_CMP_MSG_free(rep);
754     return result;
755 }
756 
757 int OSSL_CMP_exec_RR_ses(OSSL_CMP_CTX *ctx)
758 {
759     OSSL_CMP_MSG *rr = NULL;
760     OSSL_CMP_MSG *rp = NULL;
761     const int num_RevDetails = 1;
762     const int rsid = OSSL_CMP_REVREQSID;
763     OSSL_CMP_REVREPCONTENT *rrep = NULL;
764     OSSL_CMP_PKISI *si = NULL;
765     char buf[OSSL_CMP_PKISI_BUFLEN];
766     int ret = 0;
767 
768     if (ctx == NULL) {
769         ERR_raise(ERR_LIB_CMP, CMP_R_INVALID_ARGS);
770         return 0;
771     }
772     ctx->status = OSSL_CMP_PKISTATUS_request;
773     if (ctx->oldCert == NULL && ctx->p10CSR == NULL) {
774         ERR_raise(ERR_LIB_CMP, CMP_R_MISSING_REFERENCE_CERT);
775         return 0;
776     }
777 
778     /* OSSL_CMP_rr_new() also checks if all necessary options are set */
779     if ((rr = ossl_cmp_rr_new(ctx)) == NULL)
780         goto end;
781 
782     ctx->status = OSSL_CMP_PKISTATUS_trans;
783     if (!send_receive_check(ctx, rr, &rp, OSSL_CMP_PKIBODY_RP))
784         goto end;
785 
786     rrep = rp->body->value.rp;
787 #ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
788     if (sk_OSSL_CMP_PKISI_num(rrep->status) != num_RevDetails) {
789         ERR_raise(ERR_LIB_CMP, CMP_R_WRONG_RP_COMPONENT_COUNT);
790         goto end;
791     }
792 #else
793     if (sk_OSSL_CMP_PKISI_num(rrep->status) < 1) {
794         ERR_raise(ERR_LIB_CMP, CMP_R_WRONG_RP_COMPONENT_COUNT);
795         goto end;
796     }
797 #endif
798 
799     /* evaluate PKIStatus field */
800     si = ossl_cmp_revrepcontent_get_pkisi(rrep, rsid);
801     if (!save_statusInfo(ctx, si))
802         goto err;
803     switch (ossl_cmp_pkisi_get_status(si)) {
804     case OSSL_CMP_PKISTATUS_accepted:
805         ossl_cmp_info(ctx, "revocation accepted (PKIStatus=accepted)");
806         ret = 1;
807         break;
808     case OSSL_CMP_PKISTATUS_grantedWithMods:
809         ossl_cmp_info(ctx, "revocation accepted (PKIStatus=grantedWithMods)");
810         ret = 1;
811         break;
812     case OSSL_CMP_PKISTATUS_rejection:
813         ERR_raise(ERR_LIB_CMP, CMP_R_REQUEST_REJECTED_BY_SERVER);
814         goto err;
815     case OSSL_CMP_PKISTATUS_revocationWarning:
816         ossl_cmp_info(ctx, "revocation accepted (PKIStatus=revocationWarning)");
817         ret = 1;
818         break;
819     case OSSL_CMP_PKISTATUS_revocationNotification:
820         /* interpretation as warning or error depends on CA */
821         ossl_cmp_warn(ctx,
822                       "revocation accepted (PKIStatus=revocationNotification)");
823         ret = 1;
824         break;
825     case OSSL_CMP_PKISTATUS_waiting:
826     case OSSL_CMP_PKISTATUS_keyUpdateWarning:
827         ERR_raise(ERR_LIB_CMP, CMP_R_UNEXPECTED_PKISTATUS);
828         goto err;
829     default:
830         ERR_raise(ERR_LIB_CMP, CMP_R_UNKNOWN_PKISTATUS);
831         goto err;
832     }
833 
834     /* check any present CertId in optional revCerts field */
835     if (sk_OSSL_CRMF_CERTID_num(rrep->revCerts) >= 1) {
836         OSSL_CRMF_CERTID *cid;
837         OSSL_CRMF_CERTTEMPLATE *tmpl =
838             sk_OSSL_CMP_REVDETAILS_value(rr->body->value.rr, rsid)->certDetails;
839         const X509_NAME *issuer = OSSL_CRMF_CERTTEMPLATE_get0_issuer(tmpl);
840         const ASN1_INTEGER *serial = OSSL_CRMF_CERTTEMPLATE_get0_serialNumber(tmpl);
841 
842         if (sk_OSSL_CRMF_CERTID_num(rrep->revCerts) != num_RevDetails) {
843             ERR_raise(ERR_LIB_CMP, CMP_R_WRONG_RP_COMPONENT_COUNT);
844             ret = 0;
845             goto err;
846         }
847         if ((cid = ossl_cmp_revrepcontent_get_CertId(rrep, rsid)) == NULL) {
848             ERR_raise(ERR_LIB_CMP, CMP_R_MISSING_CERTID);
849             ret = 0;
850             goto err;
851         }
852         if (X509_NAME_cmp(issuer, OSSL_CRMF_CERTID_get0_issuer(cid)) != 0) {
853 #ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
854             ERR_raise(ERR_LIB_CMP, CMP_R_WRONG_CERTID_IN_RP);
855             ret = 0;
856             goto err;
857 #endif
858         }
859         if (ASN1_INTEGER_cmp(serial,
860                              OSSL_CRMF_CERTID_get0_serialNumber(cid)) != 0) {
861 #ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
862             ERR_raise(ERR_LIB_CMP, CMP_R_WRONG_SERIAL_IN_RP);
863             ret = 0;
864             goto err;
865 #endif
866         }
867     }
868 
869     /* check number of any optionally present crls */
870     if (rrep->crls != NULL && sk_X509_CRL_num(rrep->crls) != num_RevDetails) {
871         ERR_raise(ERR_LIB_CMP, CMP_R_WRONG_RP_COMPONENT_COUNT);
872         ret = 0;
873         goto err;
874     }
875 
876  err:
877     if (ret == 0
878             && OSSL_CMP_CTX_snprint_PKIStatus(ctx, buf, sizeof(buf)) != NULL)
879         ERR_add_error_data(1, buf);
880 
881  end:
882     OSSL_CMP_MSG_free(rr);
883     OSSL_CMP_MSG_free(rp);
884     return ret;
885 }
886 
887 STACK_OF(OSSL_CMP_ITAV) *OSSL_CMP_exec_GENM_ses(OSSL_CMP_CTX *ctx)
888 {
889     OSSL_CMP_MSG *genm;
890     OSSL_CMP_MSG *genp = NULL;
891     STACK_OF(OSSL_CMP_ITAV) *itavs = NULL;
892 
893     if (ctx == NULL) {
894         ERR_raise(ERR_LIB_CMP, CMP_R_INVALID_ARGS);
895         return NULL;
896     }
897     ctx->status = OSSL_CMP_PKISTATUS_request;
898 
899     if ((genm = ossl_cmp_genm_new(ctx)) == NULL)
900         goto err;
901 
902     ctx->status = OSSL_CMP_PKISTATUS_trans;
903     if (!send_receive_check(ctx, genm, &genp, OSSL_CMP_PKIBODY_GENP))
904         goto err;
905     ctx->status = OSSL_CMP_PKISTATUS_accepted;
906 
907     itavs = genp->body->value.genp;
908     if (itavs == NULL)
909         itavs = sk_OSSL_CMP_ITAV_new_null();
910     /* received stack of itavs not to be freed with the genp */
911     genp->body->value.genp = NULL;
912 
913  err:
914     OSSL_CMP_MSG_free(genm);
915     OSSL_CMP_MSG_free(genp);
916 
917     return itavs; /* NULL indicates error case */
918 }
919