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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 16:14:06 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 16:14:06 +0000
commiteee068778cb28ecf3c14e1bf843a95547d72c42d (patch)
tree0e07b30ddc5ea579d682d5dbe57998200d1c9ab7 /sm/certchain.c
parentInitial commit. (diff)
downloadgnupg2-eee068778cb28ecf3c14e1bf843a95547d72c42d.tar.xz
gnupg2-eee068778cb28ecf3c14e1bf843a95547d72c42d.zip
Adding upstream version 2.2.40.upstream/2.2.40upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'sm/certchain.c')
-rw-r--r--sm/certchain.c2380
1 files changed, 2380 insertions, 0 deletions
diff --git a/sm/certchain.c b/sm/certchain.c
new file mode 100644
index 0000000..d2a1800
--- /dev/null
+++ b/sm/certchain.c
@@ -0,0 +1,2380 @@
+/* certchain.c - certificate chain validation
+ * Copyright (C) 2001, 2002, 2003, 2004, 2005,
+ * 2006, 2007, 2008, 2011 Free Software Foundation, Inc.
+ *
+ * This file is part of GnuPG.
+ *
+ * GnuPG is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GnuPG is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <unistd.h>
+#include <time.h>
+#include <stdarg.h>
+#include <assert.h>
+
+#include "gpgsm.h"
+#include <gcrypt.h>
+#include <ksba.h>
+
+#include "keydb.h"
+#include "../kbx/keybox.h" /* for KEYBOX_FLAG_* */
+#include "../common/i18n.h"
+#include "../common/tlv.h"
+
+
+/* The OID for the authorityInfoAccess's caIssuers. */
+static const char oidstr_caIssuers[] = "1.3.6.1.5.5.7.48.2";
+
+
+/* Object to keep track of certain root certificates. */
+struct marktrusted_info_s
+{
+ struct marktrusted_info_s *next;
+ unsigned char fpr[20];
+};
+static struct marktrusted_info_s *marktrusted_info;
+
+
+/* While running the validation function we want to keep track of the
+ certificates in the chain. This type is used for that. */
+struct chain_item_s
+{
+ struct chain_item_s *next;
+ ksba_cert_t cert; /* The certificate. */
+ int is_root; /* The certificate is the root certificate. */
+};
+typedef struct chain_item_s *chain_item_t;
+
+
+static int is_root_cert (ksba_cert_t cert,
+ const char *issuerdn, const char *subjectdn);
+static int get_regtp_ca_info (ctrl_t ctrl, ksba_cert_t cert, int *chainlen);
+
+
+/* This function returns true if we already asked during this session
+ whether the root certificate CERT shall be marked as trusted. */
+static int
+already_asked_marktrusted (ksba_cert_t cert)
+{
+ unsigned char fpr[20];
+ struct marktrusted_info_s *r;
+
+ gpgsm_get_fingerprint (cert, GCRY_MD_SHA1, fpr, NULL);
+ /* No context switches in the loop! */
+ for (r=marktrusted_info; r; r= r->next)
+ if (!memcmp (r->fpr, fpr, 20))
+ return 1;
+ return 0;
+}
+
+/* Flag certificate CERT as already asked whether it shall be marked
+ as trusted. */
+static void
+set_already_asked_marktrusted (ksba_cert_t cert)
+{
+ unsigned char fpr[20];
+ struct marktrusted_info_s *r;
+
+ gpgsm_get_fingerprint (cert, GCRY_MD_SHA1, fpr, NULL);
+ for (r=marktrusted_info; r; r= r->next)
+ if (!memcmp (r->fpr, fpr, 20))
+ return; /* Already marked. */
+ r = xtrycalloc (1, sizeof *r);
+ if (!r)
+ return;
+ memcpy (r->fpr, fpr, 20);
+ r->next = marktrusted_info;
+ marktrusted_info = r;
+}
+
+/* If LISTMODE is true, print FORMAT using LISTMODE to FP. If
+ LISTMODE is false, use the string to print an log_info or, if
+ IS_ERROR is true, and log_error. */
+static void
+do_list (int is_error, int listmode, estream_t fp, const char *format, ...)
+{
+ va_list arg_ptr;
+
+ va_start (arg_ptr, format) ;
+ if (listmode)
+ {
+ if (fp)
+ {
+ es_fputs (" [", fp);
+ es_vfprintf (fp, format, arg_ptr);
+ es_fputs ("]\n", fp);
+ }
+ }
+ else
+ {
+ log_logv (is_error? GPGRT_LOG_ERROR: GPGRT_LOG_INFO, format, arg_ptr);
+ log_printf ("\n");
+ }
+ va_end (arg_ptr);
+}
+
+/* Return 0 if A and B are equal. */
+static int
+compare_certs (ksba_cert_t a, ksba_cert_t b)
+{
+ const unsigned char *img_a, *img_b;
+ size_t len_a, len_b;
+
+ img_a = ksba_cert_get_image (a, &len_a);
+ if (!img_a)
+ return 1;
+ img_b = ksba_cert_get_image (b, &len_b);
+ if (!img_b)
+ return 1;
+ return !(len_a == len_b && !memcmp (img_a, img_b, len_a));
+}
+
+
+/* Return true if CERT has the validityModel extensions and defines
+ the use of the chain model. */
+static int
+has_validation_model_chain (ksba_cert_t cert, int listmode, estream_t listfp)
+{
+ gpg_error_t err;
+ int idx, yes;
+ const char *oid;
+ size_t off, derlen, objlen, hdrlen;
+ const unsigned char *der;
+ int class, tag, constructed, ndef;
+ char *oidbuf;
+
+ for (idx=0; !(err=ksba_cert_get_extension (cert, idx,
+ &oid, NULL, &off, &derlen));idx++)
+ if (!strcmp (oid, "1.3.6.1.4.1.8301.3.5") )
+ break;
+ if (err)
+ return 0; /* Not found. */
+ der = ksba_cert_get_image (cert, NULL);
+ if (!der)
+ {
+ err = gpg_error (GPG_ERR_INV_OBJ); /* Oops */
+ goto leave;
+ }
+ der += off;
+
+ err = parse_ber_header (&der, &derlen, &class, &tag, &constructed,
+ &ndef, &objlen, &hdrlen);
+ if (!err && (objlen > derlen || tag != TAG_SEQUENCE))
+ err = gpg_error (GPG_ERR_INV_OBJ);
+ if (err)
+ goto leave;
+ derlen = objlen;
+ err = parse_ber_header (&der, &derlen, &class, &tag, &constructed,
+ &ndef, &objlen, &hdrlen);
+ if (!err && (objlen > derlen || tag != TAG_OBJECT_ID))
+ err = gpg_error (GPG_ERR_INV_OBJ);
+ if (err)
+ goto leave;
+ oidbuf = ksba_oid_to_str (der, objlen);
+ if (!oidbuf)
+ {
+ err = gpg_error_from_syserror ();
+ goto leave;
+ }
+
+ if (opt.verbose)
+ do_list (0, listmode, listfp,
+ _("validation model requested by certificate: %s"),
+ !strcmp (oidbuf, "1.3.6.1.4.1.8301.3.5.1")? _("chain") :
+ !strcmp (oidbuf, "1.3.6.1.4.1.8301.3.5.2")? _("shell") :
+ /* */ oidbuf);
+ yes = !strcmp (oidbuf, "1.3.6.1.4.1.8301.3.5.1");
+ ksba_free (oidbuf);
+ return yes;
+
+
+ leave:
+ log_error ("error parsing validityModel: %s\n", gpg_strerror (err));
+ return 0;
+}
+
+
+
+static int
+unknown_criticals (ksba_cert_t cert, int listmode, estream_t fp)
+{
+ static const char *known[] = {
+ "2.5.29.15", /* keyUsage */
+ "2.5.29.17", /* subjectAltName
+ Japanese DoCoMo certs mark them as critical. PKIX
+ only requires them as critical if subjectName is
+ empty. I don't know whether our code gracefully
+ handles such empry subjectNames but that is
+ another story. */
+ "2.5.29.19", /* basic Constraints */
+ "2.5.29.32", /* certificatePolicies */
+ "2.5.29.37", /* extendedKeyUsage - handled by certlist.c */
+ "1.3.6.1.4.1.8301.3.5", /* validityModel - handled here. */
+ NULL
+ };
+ int rc = 0, i, idx, crit;
+ const char *oid;
+ gpg_error_t err;
+ int unsupported;
+ strlist_t sl;
+
+ for (idx=0; !(err=ksba_cert_get_extension (cert, idx,
+ &oid, &crit, NULL, NULL));idx++)
+ {
+ if (!crit)
+ continue;
+ for (i=0; known[i] && strcmp (known[i],oid); i++)
+ ;
+ unsupported = !known[i];
+
+ /* If this critical extension is not supported. Check the list
+ of to be ignored extensions to see whether we claim that it
+ is supported. */
+ if (unsupported && opt.ignored_cert_extensions)
+ {
+ for (sl=opt.ignored_cert_extensions;
+ sl && strcmp (sl->d, oid); sl = sl->next)
+ ;
+ if (sl)
+ unsupported = 0;
+ }
+ if (unsupported)
+ {
+ do_list (1, listmode, fp,
+ _("critical certificate extension %s is not supported"),
+ oid);
+ rc = gpg_error (GPG_ERR_UNSUPPORTED_CERT);
+ }
+ }
+ /* We ignore the error codes EOF as well as no-value. The later will
+ occur for certificates with no extensions at all. */
+ if (err
+ && gpg_err_code (err) != GPG_ERR_EOF
+ && gpg_err_code (err) != GPG_ERR_NO_VALUE)
+ rc = err;
+
+ return rc;
+}
+
+
+/* Check whether CERT is an allowed certificate. This requires that
+ CERT matches all requirements for such a CA, i.e. the
+ BasicConstraints extension. The function returns 0 on success and
+ the allowed length of the chain at CHAINLEN. */
+static int
+allowed_ca (ctrl_t ctrl,
+ ksba_cert_t cert, int *chainlen, int listmode, estream_t fp)
+{
+ gpg_error_t err;
+ int flag;
+
+ err = ksba_cert_is_ca (cert, &flag, chainlen);
+ if (err)
+ return err;
+ if (!flag)
+ {
+ if (get_regtp_ca_info (ctrl, cert, chainlen))
+ {
+ /* Note that dirmngr takes a different way to cope with such
+ certs. */
+ return 0; /* RegTP issued certificate. */
+ }
+
+ do_list (1, listmode, fp,_("issuer certificate is not marked as a CA"));
+ return gpg_error (GPG_ERR_BAD_CA_CERT);
+ }
+ return 0;
+}
+
+
+static int
+check_cert_policy (ksba_cert_t cert, int listmode, estream_t fplist)
+{
+ gpg_error_t err;
+ char *policies;
+ estream_t fp;
+ int any_critical;
+
+ err = ksba_cert_get_cert_policies (cert, &policies);
+ if (gpg_err_code (err) == GPG_ERR_NO_DATA)
+ return 0; /* No policy given. */
+ if (err)
+ return err;
+
+ /* STRING is a line delimited list of certificate policies as stored
+ in the certificate. The line itself is colon delimited where the
+ first field is the OID of the policy and the second field either
+ N or C for normal or critical extension */
+
+ if (opt.verbose > 1 && !listmode)
+ log_info ("certificate's policy list: %s\n", policies);
+
+ /* The check is very minimal but won't give false positives */
+ any_critical = !!strstr (policies, ":C");
+
+ if (!opt.policy_file)
+ {
+ xfree (policies);
+ if (any_critical)
+ {
+ do_list (1, listmode, fplist,
+ _("critical marked policy without configured policies"));
+ return gpg_error (GPG_ERR_NO_POLICY_MATCH);
+ }
+ return 0;
+ }
+
+ fp = es_fopen (opt.policy_file, "r");
+ if (!fp)
+ {
+ if (opt.verbose || errno != ENOENT)
+ log_info (_("failed to open '%s': %s\n"),
+ opt.policy_file, strerror (errno));
+ xfree (policies);
+ /* With no critical policies this is only a warning */
+ if (!any_critical)
+ {
+ if (!opt.quiet)
+ do_list (0, listmode, fplist,
+ _("Note: non-critical certificate policy not allowed"));
+ return 0;
+ }
+ do_list (1, listmode, fplist,
+ _("certificate policy not allowed"));
+ return gpg_error (GPG_ERR_NO_POLICY_MATCH);
+ }
+
+ for (;;)
+ {
+ int c;
+ char *p, line[256];
+ char *haystack, *allowed;
+
+ /* read line */
+ do
+ {
+ if (!es_fgets (line, DIM(line)-1, fp) )
+ {
+ gpg_error_t tmperr = gpg_error_from_syserror ();
+
+ xfree (policies);
+ if (es_feof (fp))
+ {
+ es_fclose (fp);
+ /* With no critical policies this is only a warning */
+ if (!any_critical)
+ {
+ do_list (0, listmode, fplist,
+ _("Note: non-critical certificate policy not allowed"));
+ return 0;
+ }
+ do_list (1, listmode, fplist,
+ _("certificate policy not allowed"));
+ return gpg_error (GPG_ERR_NO_POLICY_MATCH);
+ }
+ es_fclose (fp);
+ return tmperr;
+ }
+
+ if (!*line || line[strlen(line)-1] != '\n')
+ {
+ /* eat until end of line */
+ while ((c = es_getc (fp)) != EOF && c != '\n')
+ ;
+ es_fclose (fp);
+ xfree (policies);
+ return gpg_error (*line? GPG_ERR_LINE_TOO_LONG
+ : GPG_ERR_INCOMPLETE_LINE);
+ }
+
+ /* Allow for empty lines and spaces */
+ for (p=line; spacep (p); p++)
+ ;
+ }
+ while (!*p || *p == '\n' || *p == '#');
+
+ /* Parse line. Note that the line has always a LF and spacep
+ does not consider a LF a space. Thus strpbrk will always
+ succeed. */
+ for (allowed=line; spacep (allowed); allowed++)
+ ;
+ p = strpbrk (allowed, " :\n");
+ if (!*p || p == allowed)
+ {
+ es_fclose (fp);
+ xfree (policies);
+ return gpg_error (GPG_ERR_CONFIGURATION);
+ }
+ *p = 0; /* strip the rest of the line */
+ /* See whether we find ALLOWED (which is an OID) in POLICIES */
+ for (haystack=policies; (p=strstr (haystack, allowed)); haystack = p+1)
+ {
+ if ( !(p == policies || p[-1] == '\n') )
+ continue; /* Does not match the begin of a line. */
+ if (p[strlen (allowed)] != ':')
+ continue; /* The length does not match. */
+ /* Yep - it does match so return okay. */
+ es_fclose (fp);
+ xfree (policies);
+ return 0;
+ }
+ }
+}
+
+
+/* Helper function for find_up. This resets the key handle and search
+ for an issuer ISSUER with a subjectKeyIdentifier of KEYID. Returns
+ 0 on success or -1 when not found. */
+static int
+find_up_search_by_keyid (ctrl_t ctrl, KEYDB_HANDLE kh,
+ const char *issuer, ksba_sexp_t keyid)
+{
+ int rc;
+ ksba_cert_t cert = NULL;
+ ksba_sexp_t subj = NULL;
+ ksba_isotime_t not_before, not_after, last_not_before, ne_last_not_before;
+ ksba_cert_t found_cert = NULL;
+ ksba_cert_t ne_found_cert = NULL;
+
+ keydb_search_reset (kh);
+ while (!(rc = keydb_search_subject (ctrl, kh, issuer)))
+ {
+ ksba_cert_release (cert); cert = NULL;
+ rc = keydb_get_cert (kh, &cert);
+ if (rc)
+ {
+ log_error ("keydb_get_cert() failed: rc=%d\n", rc);
+ rc = -1;
+ goto leave;
+ }
+ xfree (subj);
+ if (!ksba_cert_get_subj_key_id (cert, NULL, &subj))
+ {
+ if (!cmp_simple_canon_sexp (keyid, subj))
+ {
+ /* Found matching cert. */
+ rc = ksba_cert_get_validity (cert, 0, not_before);
+ if (!rc)
+ rc = ksba_cert_get_validity (cert, 1, not_after);
+ if (rc)
+ {
+ log_error ("keydb_get_validity() failed: rc=%d\n", rc);
+ rc = -1;
+ goto leave;
+ }
+
+ if (!found_cert
+ || strcmp (last_not_before, not_before) < 0)
+ {
+ /* This certificate is the first one found or newer
+ * than the previous one. This copes with
+ * re-issuing CA certificates while keeping the same
+ * key information. */
+ gnupg_copy_time (last_not_before, not_before);
+ ksba_cert_release (found_cert);
+ ksba_cert_ref ((found_cert = cert));
+ keydb_push_found_state (kh);
+ }
+
+ if (*not_after && strcmp (ctrl->current_time, not_after) > 0 )
+ ; /* CERT has expired - don't consider it. */
+ else if (!ne_found_cert
+ || strcmp (ne_last_not_before, not_before) < 0)
+ {
+ /* This certificate is the first non-expired one
+ * found or newer than the previous non-expired one. */
+ gnupg_copy_time (ne_last_not_before, not_before);
+ ksba_cert_release (ne_found_cert);
+ ksba_cert_ref ((ne_found_cert = cert));
+ }
+ }
+ }
+ }
+
+ if (!found_cert)
+ goto leave;
+
+ /* Take the last saved one. Note that push/pop_found_state are
+ * misnomers because there is no stack of states. Renaming them to
+ * save/restore_found_state would be better. */
+ keydb_pop_found_state (kh);
+ rc = 0; /* Ignore EOF or other error after the first cert. */
+
+ /* We need to consider some corner cases. It is possible that we
+ * have a long term certificate (e.g. valid from 2008 to 2033) as
+ * well as a re-issued (i.e. using the same key material) short term
+ * certificate (say from 2016 to 2019). Using the short term
+ * certificate is the proper solution. But we need to take care if
+ * there is no re-issued new short term certificate (e.g. from 2020
+ * to 2023) available. In that case it is better to use the long
+ * term certificate which is still valid. The code may run into
+ * minor problems in the case of the chain validation mode. Given
+ * that this corner case is due to non-diligent PKI management we
+ * ignore this problem. */
+
+ /* The most common case is that the found certificate is not expired
+ * and thus identical to the one found from the list of non-expired
+ * certs. We can stop here. */
+ if (found_cert == ne_found_cert)
+ goto leave;
+ /* If we do not have a non expired certificate the actual cert is
+ * expired and we can also stop here. */
+ if (!ne_found_cert)
+ goto leave;
+ /* Now we need to see whether the found certificate is expired and
+ * only in this case we return the certificate found in the list of
+ * non-expired certs. */
+ rc = ksba_cert_get_validity (found_cert, 1, not_after);
+ if (rc)
+ {
+ log_error ("keydb_get_validity() failed: rc=%d\n", rc);
+ rc = -1;
+ goto leave;
+ }
+ if (*not_after && strcmp (ctrl->current_time, not_after) > 0 )
+ { /* CERT has expired. Use the NE_FOUND_CERT. Because we have no
+ * found state for this we need to search for it again. */
+ unsigned char fpr[20];
+
+ gpgsm_get_fingerprint (ne_found_cert, GCRY_MD_SHA1, fpr, NULL);
+ keydb_search_reset (kh);
+ rc = keydb_search_fpr (ctrl, kh, fpr);
+ if (rc)
+ {
+ log_error ("keydb_search_fpr() failed: rc=%d\n", rc);
+ rc = -1;
+ goto leave;
+ }
+ /* Ready. The NE_FOUND_CERT is availabale via keydb_get_cert. */
+ }
+
+ leave:
+ ksba_cert_release (found_cert);
+ ksba_cert_release (ne_found_cert);
+ ksba_cert_release (cert);
+ xfree (subj);
+ return rc? -1:0;
+}
+
+
+struct find_up_store_certs_s
+{
+ ctrl_t ctrl;
+ int count;
+ unsigned int want_fpr:1;
+ unsigned int got_fpr:1;
+ unsigned char fpr[20];
+};
+
+static void
+find_up_store_certs_cb (void *cb_value, ksba_cert_t cert)
+{
+ struct find_up_store_certs_s *parm = cb_value;
+
+ if (keydb_store_cert (parm->ctrl, cert, 1, NULL))
+ log_error ("error storing issuer certificate as ephemeral\n");
+ else if (parm->want_fpr && !parm->got_fpr)
+ {
+ if (!gpgsm_get_fingerprint (cert, 0, parm->fpr, NULL))
+ log_error (_("failed to get the fingerprint\n"));
+ else
+ parm->got_fpr = 1;
+ }
+ parm->count++;
+}
+
+
+/* Helper for find_up(). Locate the certificate for ISSUER using an
+ external lookup. KH is the keydb context we are currently using.
+ On success 0 is returned and the certificate may be retrieved from
+ the keydb using keydb_get_cert(). KEYID is the keyIdentifier from
+ the AKI or NULL. */
+static int
+find_up_external (ctrl_t ctrl, KEYDB_HANDLE kh,
+ const char *issuer, ksba_sexp_t keyid)
+{
+ int rc;
+ strlist_t names = NULL;
+ struct find_up_store_certs_s find_up_store_certs_parm;
+ char *pattern;
+ const char *s;
+
+ find_up_store_certs_parm.ctrl = ctrl;
+ find_up_store_certs_parm.want_fpr = 0;
+ find_up_store_certs_parm.got_fpr = 0;
+ find_up_store_certs_parm.count = 0;
+
+ if (opt.verbose)
+ log_info (_("looking up issuer at external location\n"));
+ /* The Dirmngr process is confused about unknown attributes. As a
+ quick and ugly hack we locate the CN and use the issuer string
+ starting at this attribite. Fixme: we should have far better
+ parsing for external lookups in the Dirmngr. */
+ s = strstr (issuer, "CN=");
+ if (!s || s == issuer || s[-1] != ',')
+ s = issuer;
+ pattern = xtrymalloc (strlen (s)+2);
+ if (!pattern)
+ return gpg_error_from_syserror ();
+ strcpy (stpcpy (pattern, "/"), s);
+ add_to_strlist (&names, pattern);
+ xfree (pattern);
+
+ rc = gpgsm_dirmngr_lookup (ctrl, names, NULL, 0, find_up_store_certs_cb,
+ &find_up_store_certs_parm);
+ free_strlist (names);
+
+ if (opt.verbose)
+ log_info (_("number of issuers matching: %d\n"),
+ find_up_store_certs_parm.count);
+ if (rc)
+ {
+ log_error ("external key lookup failed: %s\n", gpg_strerror (rc));
+ rc = -1;
+ }
+ else if (!find_up_store_certs_parm.count)
+ rc = -1;
+ else
+ {
+ int old;
+ /* The issuers are currently stored in the ephemeral key DB, so
+ we temporary switch to ephemeral mode. */
+ old = keydb_set_ephemeral (kh, 1);
+ if (keyid)
+ rc = find_up_search_by_keyid (ctrl, kh, issuer, keyid);
+ else
+ {
+ keydb_search_reset (kh);
+ rc = keydb_search_subject (ctrl, kh, issuer);
+ }
+ keydb_set_ephemeral (kh, old);
+ }
+ return rc;
+}
+
+
+/* Helper for find_up(). Locate the certificate for CERT using the
+ * caIssuer from the authorityInfoAccess. KH is the keydb context we
+ * are currently using. On success 0 is returned and the certificate
+ * may be retrieved from the keydb using keydb_get_cert(). If no
+ * suitable authorityInfoAccess is encoded in the certificate
+ * GPG_ERR_NOT_FOUND is returned. */
+static gpg_error_t
+find_up_via_auth_info_access (ctrl_t ctrl, KEYDB_HANDLE kh, ksba_cert_t cert)
+{
+ gpg_error_t err;
+ struct find_up_store_certs_s find_up_store_certs_parm;
+ char *url, *ldapurl;
+ int idx, i;
+ char *oid;
+ ksba_name_t name;
+
+ find_up_store_certs_parm.ctrl = ctrl;
+ find_up_store_certs_parm.want_fpr = 1;
+ find_up_store_certs_parm.got_fpr = 0;
+ find_up_store_certs_parm.count = 0;
+
+ /* Find suitable URLs; if there is a http scheme we prefer that. */
+ url = ldapurl = NULL;
+ for (idx=0;
+ !url && !(err = ksba_cert_get_authority_info_access (cert, idx,
+ &oid, &name));
+ idx++)
+ {
+ if (!strcmp (oid, oidstr_caIssuers))
+ {
+ for (i=0; !url && ksba_name_enum (name, i); i++)
+ {
+ char *p = ksba_name_get_uri (name, i);
+ if (p)
+ {
+ if (!strncmp (p, "http:", 5) || !strncmp (p, "https:", 6))
+ url = p;
+ else if (ldapurl)
+ xfree (p); /* We already got one. */
+ else if (!strncmp (p, "ldap:",5) || !strncmp (p, "ldaps:",6))
+ ldapurl = p;
+ }
+ else
+ xfree (p);
+ }
+ }
+ ksba_name_release (name);
+ ksba_free (oid);
+ }
+ if (err && gpg_err_code (err) != GPG_ERR_EOF)
+ {
+ log_error (_("can't get authorityInfoAccess: %s\n"), gpg_strerror (err));
+ return err;
+ }
+ if (!url && ldapurl)
+ {
+ /* No HTTP scheme; fallback to LDAP if available. */
+ url = ldapurl;
+ ldapurl = NULL;
+ }
+ xfree (ldapurl);
+ if (!url)
+ return gpg_error (GPG_ERR_NOT_FOUND);
+
+ if (opt.verbose)
+ log_info ("looking up issuer via authorityInfoAccess.caIssuers\n");
+
+ err = gpgsm_dirmngr_lookup (ctrl, NULL, url, 0, find_up_store_certs_cb,
+ &find_up_store_certs_parm);
+
+ /* Although we might receive several certificates we use only the
+ * first one. Or more exacty the first one for which we retrieved
+ * the fingerprint. */
+ if (opt.verbose)
+ log_info ("number of caIssuers found: %d\n",
+ find_up_store_certs_parm.count);
+ if (err)
+ {
+ log_error ("external URL lookup failed: %s\n", gpg_strerror (err));
+ err = gpg_error (GPG_ERR_NOT_FOUND);
+ }
+ else if (!find_up_store_certs_parm.got_fpr)
+ err = gpg_error (GPG_ERR_NOT_FOUND);
+ else
+ {
+ int old;
+ /* The retrieved certificates are currently stored in the
+ * ephemeral key DB, so we temporary switch to ephemeral
+ * mode. */
+ old = keydb_set_ephemeral (kh, 1);
+ keydb_search_reset (kh);
+ err = keydb_search_fpr (ctrl, kh, find_up_store_certs_parm.fpr);
+ keydb_set_ephemeral (kh, old);
+ }
+
+ return err;
+}
+
+
+/* Helper for find_up(). Ask the dirmngr for the certificate for
+ ISSUER with optional SERIALNO. KH is the keydb context we are
+ currently using. With SUBJECT_MODE set, ISSUER is searched as the
+ subject. On success 0 is returned and the certificate is available
+ in the ephemeral DB. */
+static int
+find_up_dirmngr (ctrl_t ctrl, KEYDB_HANDLE kh,
+ ksba_sexp_t serialno, const char *issuer, int subject_mode)
+{
+ int rc;
+ strlist_t names = NULL;
+ struct find_up_store_certs_s find_up_store_certs_parm;
+ char *pattern;
+
+ (void)kh;
+
+ find_up_store_certs_parm.ctrl = ctrl;
+ find_up_store_certs_parm.count = 0;
+
+ if (opt.verbose)
+ log_info (_("looking up issuer from the Dirmngr cache\n"));
+ if (subject_mode)
+ {
+ pattern = xtrymalloc (strlen (issuer)+2);
+ if (pattern)
+ strcpy (stpcpy (pattern, "/"), issuer);
+ }
+ else if (serialno)
+ pattern = gpgsm_format_sn_issuer (serialno, issuer);
+ else
+ {
+ pattern = xtrymalloc (strlen (issuer)+3);
+ if (pattern)
+ strcpy (stpcpy (pattern, "#/"), issuer);
+ }
+ if (!pattern)
+ return gpg_error_from_syserror ();
+ add_to_strlist (&names, pattern);
+ xfree (pattern);
+
+ rc = gpgsm_dirmngr_lookup (ctrl, names, NULL, 1, find_up_store_certs_cb,
+ &find_up_store_certs_parm);
+ free_strlist (names);
+
+ if (opt.verbose)
+ log_info (_("number of matching certificates: %d\n"),
+ find_up_store_certs_parm.count);
+ if (rc && !opt.quiet)
+ log_info (_("dirmngr cache-only key lookup failed: %s\n"),
+ gpg_strerror (rc));
+ return (!rc && find_up_store_certs_parm.count)? 0 : -1;
+}
+
+
+
+/* Locate issuing certificate for CERT. ISSUER is the name of the
+ issuer used as a fallback if the other methods don't work. If
+ FIND_NEXT is true, the function shall return the next possible
+ issuer. The certificate itself is not directly returned but a
+ keydb_get_cert on the keydb context KH will return it. Returns 0
+ on success, -1 if not found or an error code. */
+static int
+find_up (ctrl_t ctrl, KEYDB_HANDLE kh,
+ ksba_cert_t cert, const char *issuer, int find_next)
+{
+ ksba_name_t authid;
+ ksba_sexp_t authidno;
+ ksba_sexp_t keyid;
+ int rc = -1;
+
+ if (DBG_X509)
+ log_debug ("looking for parent certificate\n");
+ if (!ksba_cert_get_auth_key_id (cert, &keyid, &authid, &authidno))
+ {
+ const char *s = ksba_name_enum (authid, 0);
+ if (s && *authidno)
+ {
+ rc = keydb_search_issuer_sn (ctrl, kh, s, authidno);
+ if (rc)
+ keydb_search_reset (kh);
+
+ if (!rc && DBG_X509)
+ log_debug (" found via authid and sn+issuer\n");
+
+ /* In case of an error, try to get the certificate from the
+ dirmngr. That is done by trying to put that certifcate
+ into the ephemeral DB and let the code below do the
+ actual retrieve. Thus there is no error checking.
+ Skipped in find_next mode as usual. */
+ if (rc == -1 && !find_next)
+ find_up_dirmngr (ctrl, kh, authidno, s, 0);
+
+ /* In case of an error try the ephemeral DB. We can't do
+ that in find_next mode because we can't keep the search
+ state then. */
+ if (rc == -1 && !find_next)
+ {
+ int old = keydb_set_ephemeral (kh, 1);
+ if (!old)
+ {
+ rc = keydb_search_issuer_sn (ctrl, kh, s, authidno);
+ if (rc)
+ keydb_search_reset (kh);
+
+ if (!rc && DBG_X509)
+ log_debug (" found via authid and sn+issuer (ephem)\n");
+ }
+ keydb_set_ephemeral (kh, old);
+ }
+ if (rc)
+ rc = -1; /* Need to make sure to have this error code. */
+ }
+
+ if (rc == -1 && keyid && !find_next)
+ {
+ /* Not found by AKI.issuer_sn. Lets try the AKI.ki
+ instead. Loop over all certificates with that issuer as
+ subject and stop for the one with a matching
+ subjectKeyIdentifier. */
+ /* Fixme: Should we also search in the dirmngr? */
+ rc = find_up_search_by_keyid (ctrl, kh, issuer, keyid);
+ if (!rc && DBG_X509)
+ log_debug (" found via authid and keyid\n");
+ if (rc)
+ {
+ int old = keydb_set_ephemeral (kh, 1);
+ if (!old)
+ rc = find_up_search_by_keyid (ctrl, kh, issuer, keyid);
+ if (!rc && DBG_X509)
+ log_debug (" found via authid and keyid (ephem)\n");
+ keydb_set_ephemeral (kh, old);
+ }
+ if (rc)
+ rc = -1; /* Need to make sure to have this error code. */
+ }
+
+ /* If we still didn't found it, try to find it via the subject
+ from the dirmngr-cache. */
+ if (rc == -1 && !find_next)
+ {
+ if (!find_up_dirmngr (ctrl, kh, NULL, issuer, 1))
+ {
+ int old = keydb_set_ephemeral (kh, 1);
+ if (keyid)
+ rc = find_up_search_by_keyid (ctrl, kh, issuer, keyid);
+ else
+ {
+ keydb_search_reset (kh);
+ rc = keydb_search_subject (ctrl, kh, issuer);
+ }
+ keydb_set_ephemeral (kh, old);
+ }
+ if (rc)
+ rc = -1; /* Need to make sure to have this error code. */
+
+ if (!rc && DBG_X509)
+ log_debug (" found via authid and issuer from dirmngr cache\n");
+ }
+
+ /* If we still didn't found it, try an external lookup. */
+ if (rc == -1 && !find_next && !ctrl->offline)
+ {
+ /* We allow AIA also if CRLs are enabled; both can be used
+ * as a web bug so it does not make sense to not use AIA if
+ * CRL checks are enabled. */
+ if ((opt.auto_issuer_key_retrieve || !opt.no_crl_check)
+ && !find_up_via_auth_info_access (ctrl, kh, cert))
+ {
+ if (DBG_X509)
+ log_debug (" found via authorityInfoAccess.caIssuers\n");
+ rc = 0;
+ }
+ else if (opt.auto_issuer_key_retrieve)
+ {
+ rc = find_up_external (ctrl, kh, issuer, keyid);
+ if (!rc && DBG_X509)
+ log_debug (" found via authid and external lookup\n");
+ }
+ }
+
+
+ /* Print a note so that the user does not feel too helpless when
+ an issuer certificate was found and gpgsm prints BAD
+ signature because it is not the correct one. */
+ if (rc == -1 && opt.quiet)
+ ;
+ else if (rc == -1)
+ {
+ log_info ("%sissuer certificate ", find_next?"next ":"");
+ if (keyid)
+ {
+ log_printf ("{");
+ gpgsm_dump_serial (keyid);
+ log_printf ("} ");
+ }
+ if (authidno)
+ {
+ log_printf ("(#");
+ gpgsm_dump_serial (authidno);
+ log_printf ("/");
+ gpgsm_dump_string (s);
+ log_printf (") ");
+ }
+ log_printf ("not found using authorityKeyIdentifier\n");
+ }
+ else if (rc)
+ log_error ("failed to find authorityKeyIdentifier: rc=%d\n", rc);
+ xfree (keyid);
+ ksba_name_release (authid);
+ xfree (authidno);
+ }
+
+ if (rc) /* Not found via authorithyKeyIdentifier, try regular issuer name. */
+ rc = keydb_search_subject (ctrl, kh, issuer);
+ if (rc == -1 && !find_next)
+ {
+ int old;
+
+ /* Also try to get it from the Dirmngr cache. The function
+ merely puts it into the ephemeral database. */
+ find_up_dirmngr (ctrl, kh, NULL, issuer, 0);
+
+ /* Not found, let us see whether we have one in the ephemeral key DB. */
+ old = keydb_set_ephemeral (kh, 1);
+ if (!old)
+ {
+ keydb_search_reset (kh);
+ rc = keydb_search_subject (ctrl, kh, issuer);
+ }
+ keydb_set_ephemeral (kh, old);
+
+ if (!rc && DBG_X509)
+ log_debug (" found via issuer\n");
+ }
+
+ /* Still not found. If enabled, try an external lookup. */
+ if (rc == -1 && !find_next && !ctrl->offline)
+ {
+ if ((opt.auto_issuer_key_retrieve || !opt.no_crl_check)
+ && !find_up_via_auth_info_access (ctrl, kh, cert))
+ {
+ if (DBG_X509)
+ log_debug (" found via authorityInfoAccess.caIssuers\n");
+ rc = 0;
+ }
+ else if (opt.auto_issuer_key_retrieve)
+ {
+ rc = find_up_external (ctrl, kh, issuer, NULL);
+ if (!rc && DBG_X509)
+ log_debug (" found via issuer and external lookup\n");
+ }
+ }
+
+ return rc;
+}
+
+
+/* Return the next certificate up in the chain starting at START.
+ Returns -1 when there are no more certificates. */
+int
+gpgsm_walk_cert_chain (ctrl_t ctrl, ksba_cert_t start, ksba_cert_t *r_next)
+{
+ int rc = 0;
+ char *issuer = NULL;
+ char *subject = NULL;
+ KEYDB_HANDLE kh = keydb_new ();
+
+ *r_next = NULL;
+ if (!kh)
+ {
+ log_error (_("failed to allocate keyDB handle\n"));
+ rc = gpg_error (GPG_ERR_GENERAL);
+ goto leave;
+ }
+
+ issuer = ksba_cert_get_issuer (start, 0);
+ subject = ksba_cert_get_subject (start, 0);
+ if (!issuer)
+ {
+ log_error ("no issuer found in certificate\n");
+ rc = gpg_error (GPG_ERR_BAD_CERT);
+ goto leave;
+ }
+ if (!subject)
+ {
+ log_error ("no subject found in certificate\n");
+ rc = gpg_error (GPG_ERR_BAD_CERT);
+ goto leave;
+ }
+
+ if (is_root_cert (start, issuer, subject))
+ {
+ rc = -1; /* we are at the root */
+ goto leave;
+ }
+
+ rc = find_up (ctrl, kh, start, issuer, 0);
+ if (rc)
+ {
+ /* It is quite common not to have a certificate, so better don't
+ print an error here. */
+ if (rc != -1 && opt.verbose > 1)
+ log_error ("failed to find issuer's certificate: rc=%d\n", rc);
+ rc = gpg_error (GPG_ERR_MISSING_ISSUER_CERT);
+ goto leave;
+ }
+
+ rc = keydb_get_cert (kh, r_next);
+ if (rc)
+ {
+ log_error ("keydb_get_cert() failed: rc=%d\n", rc);
+ rc = gpg_error (GPG_ERR_GENERAL);
+ }
+
+ leave:
+ xfree (issuer);
+ xfree (subject);
+ keydb_release (kh);
+ return rc;
+}
+
+
+/* Helper for gpgsm_is_root_cert. This one is used if the subject and
+ issuer DNs are already known. */
+static int
+is_root_cert (ksba_cert_t cert, const char *issuerdn, const char *subjectdn)
+{
+ gpg_error_t err;
+ int result = 0;
+ ksba_sexp_t serialno;
+ ksba_sexp_t ak_keyid;
+ ksba_name_t ak_name;
+ ksba_sexp_t ak_sn;
+ const char *ak_name_str;
+ ksba_sexp_t subj_keyid = NULL;
+
+ if (!issuerdn || !subjectdn)
+ return 0; /* No. */
+
+ if (strcmp (issuerdn, subjectdn))
+ return 0; /* No. */
+
+ err = ksba_cert_get_auth_key_id (cert, &ak_keyid, &ak_name, &ak_sn);
+ if (err)
+ {
+ if (gpg_err_code (err) == GPG_ERR_NO_DATA)
+ return 1; /* Yes. Without a authorityKeyIdentifier this needs
+ to be the Root certifcate (our trust anchor). */
+ log_error ("error getting authorityKeyIdentifier: %s\n",
+ gpg_strerror (err));
+ return 0; /* Well, it is broken anyway. Return No. */
+ }
+
+ serialno = ksba_cert_get_serial (cert);
+ if (!serialno)
+ {
+ log_error ("error getting serialno: %s\n", gpg_strerror (err));
+ goto leave;
+ }
+
+ /* Check whether the auth name's matches the issuer name+sn. If
+ that is the case this is a root certificate. */
+ ak_name_str = ksba_name_enum (ak_name, 0);
+ if (ak_name_str
+ && !strcmp (ak_name_str, issuerdn)
+ && !cmp_simple_canon_sexp (ak_sn, serialno))
+ {
+ result = 1; /* Right, CERT is self-signed. */
+ goto leave;
+ }
+
+ /* Similar for the ak_keyid. */
+ if (ak_keyid && !ksba_cert_get_subj_key_id (cert, NULL, &subj_keyid)
+ && !cmp_simple_canon_sexp (ak_keyid, subj_keyid))
+ {
+ result = 1; /* Right, CERT is self-signed. */
+ goto leave;
+ }
+
+
+ leave:
+ ksba_free (subj_keyid);
+ ksba_free (ak_keyid);
+ ksba_name_release (ak_name);
+ ksba_free (ak_sn);
+ ksba_free (serialno);
+ return result;
+}
+
+
+
+/* Check whether the CERT is a root certificate. Returns True if this
+ is the case. */
+int
+gpgsm_is_root_cert (ksba_cert_t cert)
+{
+ char *issuer;
+ char *subject;
+ int yes;
+
+ issuer = ksba_cert_get_issuer (cert, 0);
+ subject = ksba_cert_get_subject (cert, 0);
+ yes = is_root_cert (cert, issuer, subject);
+ xfree (issuer);
+ xfree (subject);
+ return yes;
+}
+
+
+/* This is a helper for gpgsm_validate_chain. */
+static gpg_error_t
+is_cert_still_valid (ctrl_t ctrl, int force_ocsp, int lm, estream_t fp,
+ ksba_cert_t subject_cert, ksba_cert_t issuer_cert,
+ int *any_revoked, int *any_no_crl, int *any_crl_too_old)
+{
+ gpg_error_t err;
+
+ if (ctrl->offline || (opt.no_crl_check && !ctrl->use_ocsp))
+ {
+ audit_log_ok (ctrl->audit, AUDIT_CRL_CHECK,
+ gpg_error (GPG_ERR_NOT_ENABLED));
+ return 0;
+ }
+
+
+ if (!(force_ocsp || ctrl->use_ocsp)
+ && !opt.enable_issuer_based_crl_check)
+ {
+ err = ksba_cert_get_crl_dist_point (subject_cert, 0, NULL, NULL, NULL);
+ if (gpg_err_code (err) == GPG_ERR_EOF)
+ {
+ /* No DP specified in the certificate. Thus the CA does not
+ * consider a CRL useful and the user of the certificate
+ * also does not consider this to be a critical thing. In
+ * this case we can conclude that the certificate shall not
+ * be revocable. Note that we reach this point here only if
+ * no OCSP responder shall be used. */
+ audit_log_ok (ctrl->audit, AUDIT_CRL_CHECK, gpg_error (GPG_ERR_TRUE));
+ return 0;
+ }
+ }
+
+ err = gpgsm_dirmngr_isvalid (ctrl,
+ subject_cert, issuer_cert,
+ force_ocsp? 2 : !!ctrl->use_ocsp);
+ audit_log_ok (ctrl->audit, AUDIT_CRL_CHECK, err);
+
+ if (err)
+ {
+ if (!lm)
+ gpgsm_cert_log_name (NULL, subject_cert);
+ switch (gpg_err_code (err))
+ {
+ case GPG_ERR_CERT_REVOKED:
+ do_list (1, lm, fp, _("certificate has been revoked"));
+ *any_revoked = 1;
+ /* Store that in the keybox so that key listings are able to
+ return the revoked flag. We don't care about error,
+ though. */
+ keydb_set_cert_flags (ctrl, subject_cert, 1, KEYBOX_FLAG_VALIDITY, 0,
+ ~0, VALIDITY_REVOKED);
+ break;
+
+ case GPG_ERR_NO_CRL_KNOWN:
+ do_list (1, lm, fp, _("no CRL found for certificate"));
+ *any_no_crl = 1;
+ break;
+
+ case GPG_ERR_NO_DATA:
+ do_list (1, lm, fp, _("the status of the certificate is unknown"));
+ *any_no_crl = 1;
+ break;
+
+ case GPG_ERR_CRL_TOO_OLD:
+ do_list (1, lm, fp, _("the available CRL is too old"));
+ if (!lm)
+ log_info (_("please make sure that the "
+ "\"dirmngr\" is properly installed\n"));
+ *any_crl_too_old = 1;
+ break;
+
+ default:
+ do_list (1, lm, fp, _("checking the CRL failed: %s"),
+ gpg_strerror (err));
+ return err;
+ }
+ }
+ return 0;
+}
+
+
+/* Helper for gpgsm_validate_chain to check the validity period of
+ SUBJECT_CERT. The caller needs to pass EXPTIME which will be
+ updated to the nearest expiration time seen. A DEPTH of 0 indicates
+ the target certificate, -1 the final root certificate and other
+ values intermediate certificates. */
+static gpg_error_t
+check_validity_period (ksba_isotime_t current_time,
+ ksba_cert_t subject_cert,
+ ksba_isotime_t exptime,
+ int listmode, estream_t listfp, int depth)
+{
+ gpg_error_t err;
+ ksba_isotime_t not_before, not_after;
+
+ err = ksba_cert_get_validity (subject_cert, 0, not_before);
+ if (!err)
+ err = ksba_cert_get_validity (subject_cert, 1, not_after);
+ if (err)
+ {
+ do_list (1, listmode, listfp,
+ _("certificate with invalid validity: %s"), gpg_strerror (err));
+ return gpg_error (GPG_ERR_BAD_CERT);
+ }
+
+ if (*not_after)
+ {
+ if (!*exptime)
+ gnupg_copy_time (exptime, not_after);
+ else if (strcmp (not_after, exptime) < 0 )
+ gnupg_copy_time (exptime, not_after);
+ }
+
+ if (*not_before && strcmp (current_time, not_before) < 0 )
+ {
+ do_list (1, listmode, listfp,
+ depth == 0 ? _("certificate not yet valid") :
+ depth == -1 ? _("root certificate not yet valid") :
+ /* other */ _("intermediate certificate not yet valid"));
+ if (!listmode)
+ {
+ log_info (" (valid from ");
+ dump_isotime (not_before);
+ log_printf (")\n");
+ }
+ return gpg_error (GPG_ERR_CERT_TOO_YOUNG);
+ }
+
+ if (*not_after && strcmp (current_time, not_after) > 0 )
+ {
+ do_list (opt.ignore_expiration?0:1, listmode, listfp,
+ depth == 0 ? _("certificate has expired") :
+ depth == -1 ? _("root certificate has expired") :
+ /* other */ _("intermediate certificate has expired"));
+ if (!listmode)
+ {
+ log_info (" (expired at ");
+ dump_isotime (not_after);
+ log_printf (")\n");
+ }
+ if (opt.ignore_expiration)
+ log_info ("WARNING: ignoring expiration\n");
+ else
+ return gpg_error (GPG_ERR_CERT_EXPIRED);
+ }
+
+ return 0;
+}
+
+/* This is a variant of check_validity_period used with the chain
+ model. The dextra contraint here is that notBefore and notAfter
+ must exists and if the additional argument CHECK_TIME is given this
+ time is used to check the validity period of SUBJECT_CERT. */
+static gpg_error_t
+check_validity_period_cm (ksba_isotime_t current_time,
+ ksba_isotime_t check_time,
+ ksba_cert_t subject_cert,
+ ksba_isotime_t exptime,
+ int listmode, estream_t listfp, int depth)
+{
+ gpg_error_t err;
+ ksba_isotime_t not_before, not_after;
+
+ err = ksba_cert_get_validity (subject_cert, 0, not_before);
+ if (!err)
+ err = ksba_cert_get_validity (subject_cert, 1, not_after);
+ if (err)
+ {
+ do_list (1, listmode, listfp,
+ _("certificate with invalid validity: %s"), gpg_strerror (err));
+ return gpg_error (GPG_ERR_BAD_CERT);
+ }
+ if (!*not_before || !*not_after)
+ {
+ do_list (1, listmode, listfp,
+ _("required certificate attributes missing: %s%s%s"),
+ !*not_before? "notBefore":"",
+ (!*not_before && !*not_after)? ", ":"",
+ !*not_before? "notAfter":"");
+ return gpg_error (GPG_ERR_BAD_CERT);
+ }
+ if (strcmp (not_before, not_after) > 0 )
+ {
+ do_list (1, listmode, listfp,
+ _("certificate with invalid validity"));
+ log_info (" (valid from ");
+ dump_isotime (not_before);
+ log_printf (" expired at ");
+ dump_isotime (not_after);
+ log_printf (")\n");
+ return gpg_error (GPG_ERR_BAD_CERT);
+ }
+
+ if (!*exptime)
+ gnupg_copy_time (exptime, not_after);
+ else if (strcmp (not_after, exptime) < 0 )
+ gnupg_copy_time (exptime, not_after);
+
+ if (strcmp (current_time, not_before) < 0 )
+ {
+ do_list (1, listmode, listfp,
+ depth == 0 ? _("certificate not yet valid") :
+ depth == -1 ? _("root certificate not yet valid") :
+ /* other */ _("intermediate certificate not yet valid"));
+ if (!listmode)
+ {
+ log_info (" (valid from ");
+ dump_isotime (not_before);
+ log_printf (")\n");
+ }
+ return gpg_error (GPG_ERR_CERT_TOO_YOUNG);
+ }
+
+ if (*check_time
+ && (strcmp (check_time, not_before) < 0
+ || strcmp (check_time, not_after) > 0))
+ {
+ /* Note that we don't need a case for the root certificate
+ because its own consitency has already been checked. */
+ do_list(opt.ignore_expiration?0:1, listmode, listfp,
+ depth == 0 ?
+ _("signature not created during lifetime of certificate") :
+ depth == 1 ?
+ _("certificate not created during lifetime of issuer") :
+ _("intermediate certificate not created during lifetime "
+ "of issuer"));
+ if (!listmode)
+ {
+ log_info (depth== 0? _(" ( signature created at ") :
+ /* */ _(" (certificate created at ") );
+ dump_isotime (check_time);
+ log_printf (")\n");
+ log_info (depth==0? _(" (certificate valid from ") :
+ /* */ _(" ( issuer valid from ") );
+ dump_isotime (not_before);
+ log_info (" to ");
+ dump_isotime (not_after);
+ log_printf (")\n");
+ }
+ if (opt.ignore_expiration)
+ log_info ("WARNING: ignoring expiration\n");
+ else
+ return gpg_error (GPG_ERR_CERT_EXPIRED);
+ }
+
+ return 0;
+}
+
+
+
+/* Ask the user whether he wants to mark the certificate CERT trusted.
+ Returns true if the CERT is the trusted. We also check whether the
+ agent is at all enabled to allow marktrusted and don't call it in
+ this session again if it is not. */
+static int
+ask_marktrusted (ctrl_t ctrl, ksba_cert_t cert, int listmode)
+{
+ static int no_more_questions;
+ int rc;
+ char *fpr;
+ int success = 0;
+
+ fpr = gpgsm_get_fingerprint_string (cert, GCRY_MD_SHA1);
+ log_info (_("fingerprint=%s\n"), fpr? fpr : "?");
+ xfree (fpr);
+
+ if (no_more_questions)
+ rc = gpg_error (GPG_ERR_NOT_SUPPORTED);
+ else
+ rc = gpgsm_agent_marktrusted (ctrl, cert);
+ if (!rc)
+ {
+ log_info (_("root certificate has now been marked as trusted\n"));
+ success = 1;
+ }
+ else if (!listmode)
+ {
+ gpgsm_dump_cert ("issuer", cert);
+ log_info ("after checking the fingerprint, you may want "
+ "to add it manually to the list of trusted certificates.\n");
+ }
+
+ if (gpg_err_code (rc) == GPG_ERR_NOT_SUPPORTED)
+ {
+ if (!no_more_questions)
+ log_info (_("interactive marking as trusted "
+ "not enabled in gpg-agent\n"));
+ no_more_questions = 1;
+ }
+ else if (gpg_err_code (rc) == GPG_ERR_CANCELED)
+ {
+ log_info (_("interactive marking as trusted "
+ "disabled for this session\n"));
+ no_more_questions = 1;
+ }
+ else
+ set_already_asked_marktrusted (cert);
+
+ return success;
+}
+
+
+
+
+/* Validate a chain and optionally return the nearest expiration time
+ in R_EXPTIME. With LISTMODE set to 1 a special listmode is
+ activated where only information about the certificate is printed
+ to LISTFP and no output is send to the usual log stream. If
+ CHECKTIME_ARG is set, it is used only in the chain model instead of the
+ current time.
+
+ Defined flag bits
+
+ VALIDATE_FLAG_NO_DIRMNGR - Do not do any dirmngr isvalid checks.
+ VALIDATE_FLAG_CHAIN_MODEL - Check according to chain model.
+ VALIDATE_FLAG_STEED - Check according to the STEED model.
+*/
+static int
+do_validate_chain (ctrl_t ctrl, ksba_cert_t cert, ksba_isotime_t checktime_arg,
+ ksba_isotime_t r_exptime,
+ int listmode, estream_t listfp, unsigned int flags,
+ struct rootca_flags_s *rootca_flags)
+{
+ int rc = 0, depth, maxdepth;
+ char *issuer = NULL;
+ char *subject = NULL;
+ KEYDB_HANDLE kh = NULL;
+ ksba_cert_t subject_cert = NULL, issuer_cert = NULL;
+ ksba_isotime_t current_time;
+ ksba_isotime_t check_time;
+ ksba_isotime_t exptime;
+ int any_expired = 0;
+ int any_revoked = 0;
+ int any_no_crl = 0;
+ int any_crl_too_old = 0;
+ int any_no_policy_match = 0;
+ int is_qualified = -1; /* Indicates whether the certificate stems
+ from a qualified root certificate.
+ -1 = unknown, 0 = no, 1 = yes. */
+ chain_item_t chain = NULL; /* A list of all certificates in the chain. */
+
+
+ gnupg_get_isotime (current_time);
+ gnupg_copy_time (ctrl->current_time, current_time);
+
+ if ( (flags & VALIDATE_FLAG_CHAIN_MODEL) )
+ {
+ if (!strcmp (checktime_arg, "19700101T000000"))
+ {
+ do_list (1, listmode, listfp,
+ _("WARNING: creation time of signature not known - "
+ "assuming current time"));
+ gnupg_copy_time (check_time, current_time);
+ }
+ else
+ gnupg_copy_time (check_time, checktime_arg);
+ }
+ else
+ *check_time = 0;
+
+ if (r_exptime)
+ *r_exptime = 0;
+ *exptime = 0;
+
+ if (opt.no_chain_validation && !listmode)
+ {
+ log_info ("WARNING: bypassing certificate chain validation\n");
+ return 0;
+ }
+
+ kh = keydb_new ();
+ if (!kh)
+ {
+ log_error (_("failed to allocate keyDB handle\n"));
+ rc = gpg_error (GPG_ERR_GENERAL);
+ goto leave;
+ }
+
+ if (DBG_X509 && !listmode)
+ gpgsm_dump_cert ("target", cert);
+
+ subject_cert = cert;
+ ksba_cert_ref (subject_cert);
+ maxdepth = 50;
+ depth = 0;
+
+ for (;;)
+ {
+ int is_root;
+ gpg_error_t istrusted_rc = -1;
+
+ /* Put the certificate on our list. */
+ {
+ chain_item_t ci;
+
+ ci = xtrycalloc (1, sizeof *ci);
+ if (!ci)
+ {
+ rc = gpg_error_from_syserror ();
+ goto leave;
+ }
+ ksba_cert_ref (subject_cert);
+ ci->cert = subject_cert;
+ ci->next = chain;
+ chain = ci;
+ }
+
+ xfree (issuer);
+ xfree (subject);
+ issuer = ksba_cert_get_issuer (subject_cert, 0);
+ subject = ksba_cert_get_subject (subject_cert, 0);
+
+ if (!issuer)
+ {
+ do_list (1, listmode, listfp, _("no issuer found in certificate"));
+ rc = gpg_error (GPG_ERR_BAD_CERT);
+ goto leave;
+ }
+
+
+ /* Is this a self-issued certificate (i.e. the root certificate)? */
+ is_root = is_root_cert (subject_cert, issuer, subject);
+ if (is_root)
+ {
+ chain->is_root = 1;
+ /* Check early whether the certificate is listed as trusted.
+ We used to do this only later but changed it to call the
+ check right here so that we can access special flags
+ associated with that specific root certificate. */
+ if (gpgsm_cert_has_well_known_private_key (subject_cert))
+ {
+ memset (rootca_flags, 0, sizeof *rootca_flags);
+ istrusted_rc = ((flags & VALIDATE_FLAG_STEED)
+ ? 0 : gpg_error (GPG_ERR_NOT_TRUSTED));
+ }
+ else
+ istrusted_rc = gpgsm_agent_istrusted (ctrl, subject_cert, NULL,
+ rootca_flags);
+ audit_log_cert (ctrl->audit, AUDIT_ROOT_TRUSTED,
+ subject_cert, istrusted_rc);
+ /* If the chain model extended attribute is used, make sure
+ that our chain model flag is set. */
+ if (!(flags & VALIDATE_FLAG_STEED)
+ && has_validation_model_chain (subject_cert, listmode, listfp))
+ rootca_flags->chain_model = 1;
+ }
+
+
+ /* Check the validity period. */
+ if ( (flags & VALIDATE_FLAG_CHAIN_MODEL) )
+ rc = check_validity_period_cm (current_time, check_time, subject_cert,
+ exptime, listmode, listfp,
+ (depth && is_root)? -1: depth);
+ else
+ rc = check_validity_period (current_time, subject_cert,
+ exptime, listmode, listfp,
+ (depth && is_root)? -1: depth);
+ if (gpg_err_code (rc) == GPG_ERR_CERT_EXPIRED)
+ any_expired = 1;
+ else if (rc)
+ goto leave;
+
+
+ /* Assert that we understand all critical extensions. */
+ rc = unknown_criticals (subject_cert, listmode, listfp);
+ if (rc)
+ goto leave;
+
+ /* Do a policy check. */
+ if (!opt.no_policy_check)
+ {
+ rc = check_cert_policy (subject_cert, listmode, listfp);
+ if (gpg_err_code (rc) == GPG_ERR_NO_POLICY_MATCH)
+ {
+ any_no_policy_match = 1;
+ rc = 1; /* Be on the safe side and set RC. */
+ }
+ else if (rc)
+ goto leave;
+ }
+
+
+ /* If this is the root certificate we are at the end of the chain. */
+ if (is_root)
+ {
+ if (!istrusted_rc)
+ ; /* No need to check the certificate for a trusted one. */
+ else if (gpgsm_check_cert_sig (subject_cert, subject_cert) )
+ {
+ /* We only check the signature if the certificate is not
+ trusted for better diagnostics. */
+ do_list (1, listmode, listfp,
+ _("self-signed certificate has a BAD signature"));
+ if (DBG_X509)
+ {
+ gpgsm_dump_cert ("self-signing cert", subject_cert);
+ }
+ rc = gpg_error (depth? GPG_ERR_BAD_CERT_CHAIN
+ : GPG_ERR_BAD_CERT);
+ goto leave;
+ }
+ if (!rootca_flags->relax)
+ {
+ rc = allowed_ca (ctrl, subject_cert, NULL, listmode, listfp);
+ if (rc)
+ goto leave;
+ }
+
+
+ /* Set the flag for qualified signatures. This flag is
+ deduced from a list of root certificates allowed for
+ qualified signatures. */
+ if (is_qualified == -1 && !(flags & VALIDATE_FLAG_STEED))
+ {
+ gpg_error_t err;
+ size_t buflen;
+ char buf[1];
+
+ if (!ksba_cert_get_user_data (cert, "is_qualified",
+ &buf, sizeof (buf),
+ &buflen) && buflen)
+ {
+ /* We already checked this for this certificate,
+ thus we simply take it from the user data. */
+ is_qualified = !!*buf;
+ }
+ else
+ {
+ /* Need to consult the list of root certificates for
+ qualified signatures. */
+ err = gpgsm_is_in_qualified_list (ctrl, subject_cert, NULL);
+ if (!err)
+ is_qualified = 1;
+ else if ( gpg_err_code (err) == GPG_ERR_NOT_FOUND)
+ is_qualified = 0;
+ else
+ log_error ("checking the list of qualified "
+ "root certificates failed: %s\n",
+ gpg_strerror (err));
+ if ( is_qualified != -1 )
+ {
+ /* Cache the result but don't care too much
+ about an error. */
+ buf[0] = !!is_qualified;
+ err = ksba_cert_set_user_data (subject_cert,
+ "is_qualified", buf, 1);
+ if (err)
+ log_error ("set_user_data(is_qualified) failed: %s\n",
+ gpg_strerror (err));
+ }
+ }
+ }
+
+
+ /* Act on the check for a trusted root certificates. */
+ rc = istrusted_rc;
+ if (!rc)
+ ;
+ else if (gpg_err_code (rc) == GPG_ERR_NOT_TRUSTED)
+ {
+ do_list (0, listmode, listfp,
+ _("root certificate is not marked trusted"));
+ /* If we already figured out that the certificate is
+ expired it does not make much sense to ask the user
+ whether they want to trust the root certificate. We
+ should do this only if the certificate under question
+ will then be usable. If the certificate has a well
+ known private key asking the user does not make any
+ sense. */
+ if ( !any_expired
+ && !gpgsm_cert_has_well_known_private_key (subject_cert)
+ && (!listmode || !already_asked_marktrusted (subject_cert))
+ && ask_marktrusted (ctrl, subject_cert, listmode) )
+ rc = 0;
+ }
+ else
+ {
+ log_error (_("checking the trust list failed: %s\n"),
+ gpg_strerror (rc));
+ }
+
+ if (rc)
+ goto leave;
+
+ /* Check for revocations etc. */
+ if ((flags & VALIDATE_FLAG_NO_DIRMNGR))
+ ;
+ else if ((flags & VALIDATE_FLAG_STEED))
+ ; /* Fixme: check revocations via DNS. */
+ else if (opt.no_trusted_cert_crl_check || rootca_flags->relax)
+ ;
+ else
+ rc = is_cert_still_valid (ctrl,
+ (flags & VALIDATE_FLAG_CHAIN_MODEL),
+ listmode, listfp,
+ subject_cert, subject_cert,
+ &any_revoked, &any_no_crl,
+ &any_crl_too_old);
+ if (rc)
+ goto leave;
+
+ break; /* Okay: a self-signed certicate is an end-point. */
+ } /* End is_root. */
+
+
+ /* Take care that the chain does not get too long. */
+ if ((depth+1) > maxdepth)
+ {
+ do_list (1, listmode, listfp, _("certificate chain too long\n"));
+ rc = gpg_error (GPG_ERR_BAD_CERT_CHAIN);
+ goto leave;
+ }
+
+ /* Find the next cert up the tree. */
+ keydb_search_reset (kh);
+ rc = find_up (ctrl, kh, subject_cert, issuer, 0);
+ if (rc)
+ {
+ if (rc == -1)
+ {
+ do_list (0, listmode, listfp, _("issuer certificate not found"));
+ if (!listmode)
+ {
+ log_info ("issuer certificate: #/");
+ gpgsm_dump_string (issuer);
+ log_printf ("\n");
+ }
+ }
+ else
+ log_error ("failed to find issuer's certificate: rc=%d\n", rc);
+ rc = gpg_error (GPG_ERR_MISSING_ISSUER_CERT);
+ goto leave;
+ }
+
+ ksba_cert_release (issuer_cert); issuer_cert = NULL;
+ rc = keydb_get_cert (kh, &issuer_cert);
+ if (rc)
+ {
+ log_error ("keydb_get_cert() failed: rc=%d\n", rc);
+ rc = gpg_error (GPG_ERR_GENERAL);
+ goto leave;
+ }
+
+ try_another_cert:
+ if (DBG_X509)
+ {
+ log_debug ("got issuer's certificate:\n");
+ gpgsm_dump_cert ("issuer", issuer_cert);
+ }
+
+ rc = gpgsm_check_cert_sig (issuer_cert, subject_cert);
+ if (rc)
+ {
+ do_list (0, listmode, listfp, _("certificate has a BAD signature"));
+ if (DBG_X509)
+ {
+ gpgsm_dump_cert ("signing issuer", issuer_cert);
+ gpgsm_dump_cert ("signed subject", subject_cert);
+ }
+ if (gpg_err_code (rc) == GPG_ERR_BAD_SIGNATURE)
+ {
+ /* We now try to find other issuer certificates which
+ might have been used. This is required because some
+ CAs are reusing the issuer and subject DN for new
+ root certificates. */
+ /* FIXME: Do this only if we don't have an
+ AKI.keyIdentifier */
+ rc = find_up (ctrl, kh, subject_cert, issuer, 1);
+ if (!rc)
+ {
+ ksba_cert_t tmp_cert;
+
+ rc = keydb_get_cert (kh, &tmp_cert);
+ if (rc || !compare_certs (issuer_cert, tmp_cert))
+ {
+ /* The find next did not work or returned an
+ identical certificate. We better stop here
+ to avoid infinite checks. */
+ /* No need to set RC because it is not used:
+ rc = gpg_error (GPG_ERR_BAD_SIGNATURE); */
+ ksba_cert_release (tmp_cert);
+ }
+ else
+ {
+ do_list (0, listmode, listfp,
+ _("found another possible matching "
+ "CA certificate - trying again"));
+ ksba_cert_release (issuer_cert);
+ issuer_cert = tmp_cert;
+ goto try_another_cert;
+ }
+ }
+ }
+
+ /* We give a more descriptive error code than the one
+ returned from the signature checking. */
+ rc = gpg_error (GPG_ERR_BAD_CERT_CHAIN);
+ goto leave;
+ }
+
+ is_root = gpgsm_is_root_cert (issuer_cert);
+ istrusted_rc = -1;
+
+
+ /* Check that a CA is allowed to issue certificates. */
+ {
+ int chainlen;
+
+ rc = allowed_ca (ctrl, issuer_cert, &chainlen, listmode, listfp);
+ if (rc)
+ {
+ /* Not allowed. Check whether this is a trusted root
+ certificate and whether we allow special exceptions.
+ We could carry the result of the test over to the
+ regular root check at the top of the loop but for
+ clarity we won't do that. Given that the majority of
+ certificates carry proper BasicContraints our way of
+ overriding an error in the way is justified for
+ performance reasons. */
+ if (is_root)
+ {
+ if (gpgsm_cert_has_well_known_private_key (issuer_cert))
+ {
+ memset (rootca_flags, 0, sizeof *rootca_flags);
+ istrusted_rc = ((flags & VALIDATE_FLAG_STEED)
+ ? 0 : gpg_error (GPG_ERR_NOT_TRUSTED));
+ }
+ else
+ istrusted_rc = gpgsm_agent_istrusted
+ (ctrl, issuer_cert, NULL, rootca_flags);
+
+ if (!istrusted_rc && rootca_flags->relax)
+ {
+ /* Ignore the error due to the relax flag. */
+ rc = 0;
+ chainlen = -1;
+ }
+ }
+ }
+ if (rc)
+ goto leave;
+ if (chainlen >= 0 && depth > chainlen)
+ {
+ do_list (1, listmode, listfp,
+ _("certificate chain longer than allowed by CA (%d)"),
+ chainlen);
+ rc = gpg_error (GPG_ERR_BAD_CERT_CHAIN);
+ goto leave;
+ }
+ }
+
+ /* Is the certificate allowed to sign other certificates. */
+ if (!listmode)
+ {
+ rc = gpgsm_cert_use_cert_p (issuer_cert);
+ if (rc)
+ {
+ char numbuf[50];
+ sprintf (numbuf, "%d", rc);
+ gpgsm_status2 (ctrl, STATUS_ERROR, "certcert.issuer.keyusage",
+ numbuf, NULL);
+ goto leave;
+ }
+ }
+
+ /* Check for revocations etc. Note that for a root certificate
+ this test is done a second time later. This should eventually
+ be fixed. */
+ if ((flags & VALIDATE_FLAG_NO_DIRMNGR))
+ rc = 0;
+ else if ((flags & VALIDATE_FLAG_STEED))
+ rc = 0; /* Fixme: XXX */
+ else if (is_root && (opt.no_trusted_cert_crl_check
+ || (!istrusted_rc && rootca_flags->relax)))
+ rc = 0;
+ else
+ rc = is_cert_still_valid (ctrl,
+ (flags & VALIDATE_FLAG_CHAIN_MODEL),
+ listmode, listfp,
+ subject_cert, issuer_cert,
+ &any_revoked, &any_no_crl, &any_crl_too_old);
+ if (rc)
+ goto leave;
+
+
+ if (opt.verbose && !listmode)
+ log_info (depth == 0 ? _("certificate is good\n") :
+ !is_root ? _("intermediate certificate is good\n") :
+ /* other */ _("root certificate is good\n"));
+
+ /* Under the chain model the next check time is the creation
+ time of the subject certificate. */
+ if ( (flags & VALIDATE_FLAG_CHAIN_MODEL) )
+ {
+ rc = ksba_cert_get_validity (subject_cert, 0, check_time);
+ if (rc)
+ {
+ /* That will never happen as we have already checked
+ this above. */
+ BUG ();
+ }
+ }
+
+ /* For the next round the current issuer becomes the new subject. */
+ keydb_search_reset (kh);
+ ksba_cert_release (subject_cert);
+ subject_cert = issuer_cert;
+ issuer_cert = NULL;
+ depth++;
+ } /* End chain traversal. */
+
+ if (!listmode && !opt.quiet)
+ {
+ if (opt.no_policy_check)
+ log_info ("policies not checked due to %s option\n",
+ "--disable-policy-checks");
+ if (ctrl->offline || (opt.no_crl_check && !ctrl->use_ocsp))
+ log_info ("CRLs not checked due to %s option\n",
+ ctrl->offline ? "offline" : "--disable-crl-checks");
+ }
+
+ if (!rc)
+ { /* If we encountered an error somewhere during the checks, set
+ the error code to the most critical one */
+ if (any_revoked)
+ rc = gpg_error (GPG_ERR_CERT_REVOKED);
+ else if (any_expired)
+ rc = gpg_error (GPG_ERR_CERT_EXPIRED);
+ else if (any_no_crl)
+ rc = gpg_error (GPG_ERR_NO_CRL_KNOWN);
+ else if (any_crl_too_old)
+ rc = gpg_error (GPG_ERR_CRL_TOO_OLD);
+ else if (any_no_policy_match)
+ rc = gpg_error (GPG_ERR_NO_POLICY_MATCH);
+ }
+
+ leave:
+ /* If we have traversed a complete chain up to the root we will
+ reset the ephemeral flag for all these certificates. This is done
+ regardless of any error because those errors may only be
+ transient. */
+ if (chain && chain->is_root)
+ {
+ gpg_error_t err;
+ chain_item_t ci;
+
+ for (ci = chain; ci; ci = ci->next)
+ {
+ /* Note that it is possible for the last certificate in the
+ chain (i.e. our target certificate) that it has not yet
+ been stored in the keybox and thus the flag can't be set.
+ We ignore this error because it will later be stored
+ anyway. */
+ err = keydb_set_cert_flags (ctrl, ci->cert, 1, KEYBOX_FLAG_BLOB, 0,
+ KEYBOX_FLAG_BLOB_EPHEMERAL, 0);
+ if (!ci->next && gpg_err_code (err) == GPG_ERR_NOT_FOUND)
+ ;
+ else if (err)
+ log_error ("clearing ephemeral flag failed: %s\n",
+ gpg_strerror (err));
+ }
+ }
+
+ /* If we have figured something about the qualified signature
+ capability of the certificate under question, store the result as
+ user data in all certificates of the chain. We do this even if the
+ validation itself failed. */
+ if (is_qualified != -1 && !(flags & VALIDATE_FLAG_STEED))
+ {
+ gpg_error_t err;
+ chain_item_t ci;
+ char buf[1];
+
+ buf[0] = !!is_qualified;
+
+ for (ci = chain; ci; ci = ci->next)
+ {
+ err = ksba_cert_set_user_data (ci->cert, "is_qualified", buf, 1);
+ if (err)
+ {
+ log_error ("set_user_data(is_qualified) failed: %s\n",
+ gpg_strerror (err));
+ if (!rc)
+ rc = err;
+ }
+ }
+ }
+
+ /* If auditing has been enabled, record what is in the chain. */
+ if (ctrl->audit)
+ {
+ chain_item_t ci;
+
+ audit_log (ctrl->audit, AUDIT_CHAIN_BEGIN);
+ for (ci = chain; ci; ci = ci->next)
+ {
+ audit_log_cert (ctrl->audit,
+ ci->is_root? AUDIT_CHAIN_ROOTCERT : AUDIT_CHAIN_CERT,
+ ci->cert, 0);
+ }
+ audit_log (ctrl->audit, AUDIT_CHAIN_END);
+ }
+
+ if (r_exptime)
+ gnupg_copy_time (r_exptime, exptime);
+ xfree (issuer);
+ xfree (subject);
+ keydb_release (kh);
+ while (chain)
+ {
+ chain_item_t ci_next = chain->next;
+ ksba_cert_release (chain->cert);
+ xfree (chain);
+ chain = ci_next;
+ }
+ ksba_cert_release (issuer_cert);
+ ksba_cert_release (subject_cert);
+ return rc;
+}
+
+
+/* Validate a certificate chain. For a description see
+ do_validate_chain. This function is a wrapper to handle a root
+ certificate with the chain_model flag set. If RETFLAGS is not
+ NULL, flags indicating now the verification was done are stored
+ there. The only defined vits for RETFLAGS are
+ VALIDATE_FLAG_CHAIN_MODEL and VALIDATE_FLAG_STEED.
+
+ If you are verifying a signature you should set CHECKTIME to the
+ creation time of the signature. If your are verifying a
+ certificate, set it nil (i.e. the empty string). If the creation
+ date of the signature is not known use the special date
+ "19700101T000000" which is treated in a special way here. */
+int
+gpgsm_validate_chain (ctrl_t ctrl, ksba_cert_t cert, ksba_isotime_t checktime,
+ ksba_isotime_t r_exptime,
+ int listmode, estream_t listfp, unsigned int flags,
+ unsigned int *retflags)
+{
+ int rc;
+ struct rootca_flags_s rootca_flags;
+ unsigned int dummy_retflags;
+
+ if (!retflags)
+ retflags = &dummy_retflags;
+
+ /* If the session requested a certain validation mode make sure the
+ corresponding flags are set. */
+ if (ctrl->validation_model == 1)
+ flags |= VALIDATE_FLAG_CHAIN_MODEL;
+ else if (ctrl->validation_model == 2)
+ flags |= VALIDATE_FLAG_STEED;
+
+ /* If the chain model was forced, set this immediately into
+ RETFLAGS. */
+ *retflags = (flags & VALIDATE_FLAG_CHAIN_MODEL);
+
+ memset (&rootca_flags, 0, sizeof rootca_flags);
+
+ rc = do_validate_chain (ctrl, cert, checktime,
+ r_exptime, listmode, listfp, flags,
+ &rootca_flags);
+ if (!rc && (flags & VALIDATE_FLAG_STEED))
+ {
+ *retflags |= VALIDATE_FLAG_STEED;
+ }
+ else if (gpg_err_code (rc) == GPG_ERR_CERT_EXPIRED
+ && !(flags & VALIDATE_FLAG_CHAIN_MODEL)
+ && (rootca_flags.valid && rootca_flags.chain_model))
+ {
+ do_list (0, listmode, listfp, _("switching to chain model"));
+ rc = do_validate_chain (ctrl, cert, checktime,
+ r_exptime, listmode, listfp,
+ (flags |= VALIDATE_FLAG_CHAIN_MODEL),
+ &rootca_flags);
+ *retflags |= VALIDATE_FLAG_CHAIN_MODEL;
+ }
+
+ if (opt.verbose)
+ do_list (0, listmode, listfp, _("validation model used: %s"),
+ (*retflags & VALIDATE_FLAG_STEED)?
+ "steed" :
+ (*retflags & VALIDATE_FLAG_CHAIN_MODEL)?
+ _("chain"):_("shell"));
+
+ return rc;
+}
+
+
+/* Check that the given certificate is valid but DO NOT check any
+ constraints. We assume that the issuers certificate is already in
+ the DB and that this one is valid; which it should be because it
+ has been checked using this function. */
+int
+gpgsm_basic_cert_check (ctrl_t ctrl, ksba_cert_t cert)
+{
+ int rc = 0;
+ char *issuer = NULL;
+ char *subject = NULL;
+ KEYDB_HANDLE kh;
+ ksba_cert_t issuer_cert = NULL;
+
+ if (opt.no_chain_validation)
+ {
+ log_info ("WARNING: bypassing basic certificate checks\n");
+ return 0;
+ }
+
+ kh = keydb_new ();
+ if (!kh)
+ {
+ log_error (_("failed to allocate keyDB handle\n"));
+ rc = gpg_error (GPG_ERR_GENERAL);
+ goto leave;
+ }
+
+ issuer = ksba_cert_get_issuer (cert, 0);
+ subject = ksba_cert_get_subject (cert, 0);
+ if (!issuer)
+ {
+ log_error ("no issuer found in certificate\n");
+ rc = gpg_error (GPG_ERR_BAD_CERT);
+ goto leave;
+ }
+
+ if (is_root_cert (cert, issuer, subject))
+ {
+ rc = gpgsm_check_cert_sig (cert, cert);
+ if (rc)
+ {
+ log_error ("self-signed certificate has a BAD signature: %s\n",
+ gpg_strerror (rc));
+ if (DBG_X509)
+ {
+ gpgsm_dump_cert ("self-signing cert", cert);
+ }
+ rc = gpg_error (GPG_ERR_BAD_CERT);
+ goto leave;
+ }
+ }
+ else
+ {
+ /* Find the next cert up the tree. */
+ keydb_search_reset (kh);
+ rc = find_up (ctrl, kh, cert, issuer, 0);
+ if (rc)
+ {
+ if (rc == -1)
+ {
+ log_info ("issuer certificate (#/");
+ gpgsm_dump_string (issuer);
+ log_printf (") not found\n");
+ }
+ else
+ log_error ("failed to find issuer's certificate: rc=%d\n", rc);
+ rc = gpg_error (GPG_ERR_MISSING_ISSUER_CERT);
+ goto leave;
+ }
+
+ ksba_cert_release (issuer_cert); issuer_cert = NULL;
+ rc = keydb_get_cert (kh, &issuer_cert);
+ if (rc)
+ {
+ log_error ("keydb_get_cert() failed: rc=%d\n", rc);
+ rc = gpg_error (GPG_ERR_GENERAL);
+ goto leave;
+ }
+
+ rc = gpgsm_check_cert_sig (issuer_cert, cert);
+ if (rc)
+ {
+ log_error ("certificate has a BAD signature: %s\n",
+ gpg_strerror (rc));
+ if (DBG_X509)
+ {
+ gpgsm_dump_cert ("signing issuer", issuer_cert);
+ gpgsm_dump_cert ("signed subject", cert);
+ }
+ rc = gpg_error (GPG_ERR_BAD_CERT);
+ goto leave;
+ }
+ if (opt.verbose)
+ log_info (_("certificate is good\n"));
+ }
+
+ leave:
+ xfree (issuer);
+ xfree (subject);
+ keydb_release (kh);
+ ksba_cert_release (issuer_cert);
+ return rc;
+}
+
+
+
+/* Check whether the certificate CERT has been issued by the German
+ authority for qualified signature. They do not set the
+ basicConstraints and thus we need this workaround. It works by
+ looking up the root certificate and checking whether that one is
+ listed as a qualified certificate for Germany.
+
+ We also try to cache this data but as long as don't keep a
+ reference to the certificate this won't be used.
+
+ Returns: True if CERT is a RegTP issued CA cert (i.e. the root
+ certificate itself or one of the CAs). In that case CHAINLEN will
+ receive the length of the chain which is either 0 or 1.
+*/
+static int
+get_regtp_ca_info (ctrl_t ctrl, ksba_cert_t cert, int *chainlen)
+{
+ gpg_error_t err;
+ ksba_cert_t next;
+ int rc = 0;
+ int i, depth;
+ char country[3];
+ ksba_cert_t array[4];
+ char buf[2];
+ size_t buflen;
+ int dummy_chainlen;
+
+ if (!chainlen)
+ chainlen = &dummy_chainlen;
+
+ *chainlen = 0;
+ err = ksba_cert_get_user_data (cert, "regtp_ca_chainlen",
+ &buf, sizeof (buf), &buflen);
+ if (!err)
+ {
+ /* Got info. */
+ if (buflen < 2 || !*buf)
+ return 0; /* Nothing found. */
+ *chainlen = buf[1];
+ return 1; /* This is a regtp CA. */
+ }
+ else if (gpg_err_code (err) != GPG_ERR_NOT_FOUND)
+ {
+ log_error ("ksba_cert_get_user_data(%s) failed: %s\n",
+ "regtp_ca_chainlen", gpg_strerror (err));
+ return 0; /* Nothing found. */
+ }
+
+ /* Need to gather the info. This requires to walk up the chain
+ until we have found the root. Because we are only interested in
+ German Bundesnetzagentur (former RegTP) derived certificates 3
+ levels are enough. (The German signature law demands a 3 tier
+ hierarchy; thus there is only one CA between the EE and the Root
+ CA.) */
+ memset (&array, 0, sizeof array);
+
+ depth = 0;
+ ksba_cert_ref (cert);
+ array[depth++] = cert;
+ ksba_cert_ref (cert);
+ while (depth < DIM(array) && !(rc=gpgsm_walk_cert_chain (ctrl, cert, &next)))
+ {
+ ksba_cert_release (cert);
+ ksba_cert_ref (next);
+ array[depth++] = next;
+ cert = next;
+ }
+ ksba_cert_release (cert);
+ if (rc != -1 || !depth || depth == DIM(array) )
+ {
+ /* We did not reached the root. */
+ goto leave;
+ }
+
+ /* If this is a German signature law issued certificate, we store
+ additional information. */
+ if (!gpgsm_is_in_qualified_list (NULL, array[depth-1], country)
+ && !strcmp (country, "de"))
+ {
+ /* Setting the pathlen for the root CA and the CA flag for the
+ next one is all what we need to do. */
+ err = ksba_cert_set_user_data (array[depth-1], "regtp_ca_chainlen",
+ "\x01\x01", 2);
+ if (!err && depth > 1)
+ err = ksba_cert_set_user_data (array[depth-2], "regtp_ca_chainlen",
+ "\x01\x00", 2);
+ if (err)
+ log_error ("ksba_set_user_data(%s) failed: %s\n",
+ "regtp_ca_chainlen", gpg_strerror (err));
+ for (i=0; i < depth; i++)
+ ksba_cert_release (array[i]);
+ *chainlen = (depth>1? 0:1);
+ return 1;
+ }
+
+ leave:
+ /* Nothing special with this certificate. Mark the target
+ certificate anyway to avoid duplicate lookups. */
+ err = ksba_cert_set_user_data (cert, "regtp_ca_chainlen", "", 1);
+ if (err)
+ log_error ("ksba_set_user_data(%s) failed: %s\n",
+ "regtp_ca_chainlen", gpg_strerror (err));
+ for (i=0; i < depth; i++)
+ ksba_cert_release (array[i]);
+ return 0;
+}