5 X509_VERIFY_PARAM_set_flags, X509_VERIFY_PARAM_clear_flags, X509_VERIFY_PARAM_get_flags, X509_VERIFY_PARAM_set_purpose, X509_VERIFY_PARAM_set_trust, X509_VERIFY_PARAM_set_depth, X509_VERIFY_PARAM_get_depth, X509_VERIFY_PARAM_set_time, X509_VERIFY_PARAM_add0_policy, X509_VERIFY_PARAM_set1_policies, X509_VERIFY_PARAM_set1_host, X509_VERIFY_PARAM_add1_host, X509_VERIFY_PARAM_set_hostflags, X509_VERIFY_PARAM_get0_peername, X509_VERIFY_PARAM_set1_email, X509_VERIFY_PARAM_set1_ip, X509_VERIFY_PARAM_set1_ip_asc - X509 verification parameters
9 #include <openssl/x509_vfy.h>
11 int X509_VERIFY_PARAM_set_flags(X509_VERIFY_PARAM *param, unsigned long flags);
12 int X509_VERIFY_PARAM_clear_flags(X509_VERIFY_PARAM *param,
14 unsigned long X509_VERIFY_PARAM_get_flags(X509_VERIFY_PARAM *param);
16 int X509_VERIFY_PARAM_set_purpose(X509_VERIFY_PARAM *param, int purpose);
17 int X509_VERIFY_PARAM_set_trust(X509_VERIFY_PARAM *param, int trust);
19 void X509_VERIFY_PARAM_set_time(X509_VERIFY_PARAM *param, time_t t);
21 int X509_VERIFY_PARAM_add0_policy(X509_VERIFY_PARAM *param,
23 int X509_VERIFY_PARAM_set1_policies(X509_VERIFY_PARAM *param,
24 STACK_OF(ASN1_OBJECT) *policies);
26 void X509_VERIFY_PARAM_set_depth(X509_VERIFY_PARAM *param, int depth);
27 int X509_VERIFY_PARAM_get_depth(const X509_VERIFY_PARAM *param);
29 int X509_VERIFY_PARAM_set1_host(X509_VERIFY_PARAM *param,
30 const unsigned char *name, size_t namelen);
31 int X509_VERIFY_PARAM_add1_host(X509_VERIFY_PARAM *param,
32 const unsigned char *name, size_t namelen);
33 void X509_VERIFY_PARAM_set_hostflags(X509_VERIFY_PARAM *param,
35 char *X509_VERIFY_PARAM_get0_peername(X509_VERIFY_PARAM *param);
36 int X509_VERIFY_PARAM_set1_email(X509_VERIFY_PARAM *param,
37 const unsigned char *email, size_t emaillen);
38 int X509_VERIFY_PARAM_set1_ip(X509_VERIFY_PARAM *param,
39 const unsigned char *ip, size_t iplen);
40 int X509_VERIFY_PARAM_set1_ip_asc(X509_VERIFY_PARAM *param,
45 These functions manipulate the B<X509_VERIFY_PARAM> structure associated with
46 a certificate verification operation.
48 The X509_VERIFY_PARAM_set_flags() function sets the flags in B<param> by oring
49 it with B<flags>. See the B<VERIFICATION FLAGS> section for a complete
50 description of values the B<flags> parameter can take.
52 X509_VERIFY_PARAM_get_flags() returns the flags in B<param>.
54 X509_VERIFY_PARAM_clear_flags() clears the flags B<flags> in B<param>.
56 X509_VERIFY_PARAM_set_purpose() sets the verification purpose in B<param>
57 to B<purpose>. This determines the acceptable purpose of the certificate
58 chain, for example SSL client or SSL server.
60 X509_VERIFY_PARAM_set_trust() sets the trust setting in B<param> to
63 X509_VERIFY_PARAM_set_time() sets the verification time in B<param> to
64 B<t>. Normally the current time is used.
66 X509_VERIFY_PARAM_add0_policy() enables policy checking (it is disabled
67 by default) and adds B<policy> to the acceptable policy set.
69 X509_VERIFY_PARAM_set1_policies() enables policy checking (it is disabled
70 by default) and sets the acceptable policy set to B<policies>. Any existing
71 policy set is cleared. The B<policies> parameter can be B<NULL> to clear
72 an existing policy set.
74 X509_VERIFY_PARAM_set_depth() sets the maximum verification depth to B<depth>.
75 That is the maximum number of untrusted CA certificates that can appear in a
78 X509_VERIFY_PARAM_set1_host() sets the expected DNS hostname to
79 B<name> clearing any previously specified host name or names. If
80 B<name> is NULL, or empty the list of hostnames is cleared, and
81 name checks are not performed on the peer certificate. If B<name>
82 is NUL-terminated, B<namelen> may be zero, otherwise B<namelen>
83 must be set to the length of B<name>. When a hostname is specified,
84 certificate verification automatically invokes L<X509_check_host(3)>
85 with flags equal to the B<flags> argument given to
86 B<X509_VERIFY_PARAM_set_hostflags()> (default zero). Applications
87 are strongly advised to use this interface in preference to explicitly
88 calling L<X509_check_host(3)>, hostname checks are out of scope
89 with the DANE-EE(3) certificate usage, and the internal check will
90 be suppressed as appropriate when DANE support is added to OpenSSL.
92 X509_VERIFY_PARAM_add1_host() adds B<name> as an additional reference
93 identifer that can match the peer's certificate. Any previous names
94 set via X509_VERIFY_PARAM_set1_host() or X509_VERIFY_PARAM_add1_host()
95 are retained, no change is made if B<name> is NULL or empty. When
96 multiple names are configured, the peer is considered verified when
99 X509_VERIFY_PARAM_get0_peername() returns the DNS hostname or subject
100 CommonName from the peer certificate that matched one of the reference
101 identifiers. When wildcard matching is not disabled, or when a
102 reference identifier specifies a parent domain (starts with ".")
103 rather than a hostname, the peer name may be a wildcard name or a
104 sub-domain of the reference identifier respectively. The return
105 string is allocated by the library and is no longer valid once the
106 associated B<param> argument is freed. Applications must not free
109 X509_VERIFY_PARAM_set1_email() sets the expected RFC822 email address to
110 B<email>. If B<email> is NUL-terminated, B<emaillen> may be zero, otherwise
111 B<emaillen> must be set to the length of B<email>. When an email address
112 is specified, certificate verification automatically invokes
113 L<X509_check_email(3)>.
115 X509_VERIFY_PARAM_set1_ip() sets the expected IP address to B<ip>.
116 The B<ip> argument is in binary format, in network byte-order and
117 B<iplen> must be set to 4 for IPv4 and 16 for IPv6. When an IP
118 address is specified, certificate verification automatically invokes
121 X509_VERIFY_PARAM_set1_ip_asc() sets the expected IP address to
122 B<ipasc>. The B<ipasc> argument is a NUL-terminal ASCII string:
123 dotted decimal quad for IPv4 and colon-separated hexadecimal for
124 IPv6. The condensed "::" notation is supported for IPv6 addresses.
128 X509_VERIFY_PARAM_set_flags(), X509_VERIFY_PARAM_clear_flags(),
129 X509_VERIFY_PARAM_set_purpose(), X509_VERIFY_PARAM_set_trust(),
130 X509_VERIFY_PARAM_add0_policy() X509_VERIFY_PARAM_set1_policies(),
131 X509_VERIFY_PARAM_set1_host(), X509_VERIFY_PARAM_set_hostflags(),
132 X509_VERIFY_PARAM_set1_email(), X509_VERIFY_PARAM_set1_ip() and
133 X509_VERIFY_PARAM_set1_ip_asc() return 1 for success and 0 for
136 X509_VERIFY_PARAM_get_flags() returns the current verification flags.
138 X509_VERIFY_PARAM_set_time() and X509_VERIFY_PARAM_set_depth() do not return
141 X509_VERIFY_PARAM_get_depth() returns the current verification depth.
143 =head1 VERIFICATION FLAGS
145 The verification flags consists of zero or more of the following flags
148 B<X509_V_FLAG_CRL_CHECK> enables CRL checking for the certificate chain leaf
149 certificate. An error occurs if a suitable CRL cannot be found.
151 B<X509_V_FLAG_CRL_CHECK_ALL> enables CRL checking for the entire certificate
154 B<X509_V_FLAG_IGNORE_CRITICAL> disabled critical extension checking. By default
155 any unhandled critical extensions in certificates or (if checked) CRLs results
156 in a fatal error. If this flag is set unhandled critical extensions are
157 ignored. B<WARNING> setting this option for anything other than debugging
158 purposes can be a security risk. Finer control over which extensions are
159 supported can be performed in the verification callback.
161 THe B<X509_V_FLAG_X509_STRICT> flag disables workarounds for some broken
162 certificates and makes the verification strictly apply B<X509> rules.
164 B<X509_V_FLAG_ALLOW_PROXY_CERTS> enables proxy certificate verification.
166 B<X509_V_FLAG_POLICY_CHECK> enables certificate policy checking, by default
167 no policy checking is peformed. Additional information is sent to the
168 verification callback relating to policy checking.
170 B<X509_V_FLAG_EXPLICIT_POLICY>, B<X509_V_FLAG_INHIBIT_ANY> and
171 B<X509_V_FLAG_INHIBIT_MAP> set the B<require explicit policy>, B<inhibit any
172 policy> and B<inhibit policy mapping> flags respectively as defined in
173 B<RFC3280>. Policy checking is automatically enabled if any of these flags
176 If B<X509_V_FLAG_NOTIFY_POLICY> is set and the policy checking is successful
177 a special status code is set to the verification callback. This permits it
178 to examine the valid policy tree and perform additional checks or simply
179 log it for debugging purposes.
181 By default some additional features such as indirect CRLs and CRLs signed by
182 different keys are disabled. If B<X509_V_FLAG_EXTENDED_CRL_SUPPORT> is set
185 If B<X509_V_FLAG_USE_DELTAS> ise set delta CRLs (if present) are used to
186 determine certificate status. If not set deltas are ignored.
188 B<X509_V_FLAG_CHECK_SS_SIGNATURE> enables checking of the root CA self signed
189 cerificate signature. By default this check is disabled because it doesn't
190 add any additional security but in some cases applications might want to
191 check the signature anyway. A side effect of not checking the root CA
192 signature is that disabled or unsupported message digests on the root CA
193 are not treated as fatal errors.
195 The B<X509_V_FLAG_CB_ISSUER_CHECK> flag enables debugging of certificate
196 issuer checks. It is B<not> needed unless you are logging certificate
197 verification. If this flag is set then additional status codes will be sent
198 to the verification callback and it B<must> be prepared to handle such cases
199 without assuming they are hard errors.
203 The above functions should be used to manipulate verification parameters
204 instead of legacy functions which work in specific structures such as
205 X509_STORE_CTX_set_flags().
209 Delta CRL checking is currently primitive. Only a single delta can be used and
210 (partly due to limitations of B<X509_STORE>) constructed CRLs are not
213 If CRLs checking is enable CRLs are expected to be available in the
214 corresponding B<X509_STORE> structure. No attempt is made to download
215 CRLs from the CRL distribution points extension.
219 Enable CRL checking when performing certificate verification during SSL
220 connections associated with an B<SSL_CTX> structure B<ctx>:
222 X509_VERIFY_PARAM *param;
223 param = X509_VERIFY_PARAM_new();
224 X509_VERIFY_PARAM_set_flags(param, X509_V_FLAG_CRL_CHECK);
225 SSL_CTX_set1_param(ctx, param);
226 X509_VERIFY_PARAM_free(param);
230 L<X509_verify_cert(3)|X509_verify_cert(3)>,
231 L<X509_check_host(3)|X509_check_host(3)>,
232 L<X509_check_email(3)|X509_check_email(3)>,
233 L<X509_check_ip(3)|X509_check_ip(3)>