1SSL_CTX_load_verify_locations(3) OpenSSL SSL_CTX_load_verify_locations(3)
2
6 SSL_CTX_load_verify_locations - set default locations for trusted CA
7 certificates
8
10 #include <openssl/ssl.h>
11 int SSL_CTX_load_verify_locations(SSL_CTX *ctx, const char *CAfile,
13 const char *CApath);
14
16 SSL_CTX_load_verify_locations() specifies the locations for ctx, at
17 which CA certificates for verification purposes are located. The
18 certificates available via CAfile and CApath are trusted.
19
21 If CAfile is not NULL, it points to a file of CA certificates in PEM
22 format. The file can contain several CA certificates identified by
23 -----BEGIN CERTIFICATE-----
25 ... (CA certificate in base64 encoding) ...
26 -----END CERTIFICATE-----
27 sequences. Before, between, and after the certificates text is allowed
29 which can be used e.g. for descriptions of the certificates.
30 The CAfile is processed on execution of the
32 SSL_CTX_load_verify_locations() function.
33 If CApath is not NULL, it points to a directory containing CA
35 certificates in PEM format. The files each contain one CA certificate.
36 The files are looked up by the CA subject name hash value, which must
37 hence be available. If more than one CA certificate with the same name
38 hash value exist, the extension must be different (e.g. 9d66eef0.0,
39 9d66eef0.1 etc). The search is performed in the ordering of the
40 extension number, regardless of other properties of the certificates.
41 Use the c_rehash utility to create the necessary links.
42 The certificates in CApath are only looked up when required, e.g. when
44 building the certificate chain or when actually performing the
45 verification of a peer certificate.
46 When looking up CA certificates, the OpenSSL library will first search
48 the certificates in CAfile, then those in CApath. Certificate matching
49 is done based on the subject name, the key identifier (if present), and
50 the serial number as taken from the certificate to be verified. If
51 these data do not match, the next certificate will be tried. If a first
52 certificate matching the parameters is found, the verification process
53 will be performed; no other certificates for the same parameters will
54 be searched in case of failure.
55 In server mode, when requesting a client certificate, the server must
57 send the list of CAs of which it will accept client certificates. This
58 list is not influenced by the contents of CAfile or CApath and must
59 explicitly be set using the SSL_CTX_set_client_CA_list(3) family of
60 functions.
61 When building its own certificate chain, an OpenSSL client/server will
63 try to fill in missing certificates from CAfile/CApath, if the
64 certificate chain was not explicitly specified (see
65 SSL_CTX_add_extra_chain_cert(3), SSL_CTX_use_certificate(3).
66
68 If several CA certificates matching the name, key identifier, and
69 serial number condition are available, only the first one will be
70 examined. This may lead to unexpected results if the same CA
71 certificate is available with different expiration dates. If a
72 "certificate expired" verification error occurs, no other certificate
73 will be searched. Make sure to not have expired certificates mixed with
74 valid ones.
75
77 Generate a CA certificate file with descriptive text from the CA
78 certificates ca1.pem ca2.pem ca3.pem:
79 #!/bin/sh
81 rm CAfile.pem
82 for i in ca1.pem ca2.pem ca3.pem ; do
83 openssl x509 -in $i -text >> CAfile.pem
84 done
85 Prepare the directory /some/where/certs containing several CA
87 certificates for use as CApath:
88 cd /some/where/certs
90 c_rehash .
91
93 The following return values can occur:
94 0 The operation failed because CAfile and CApath are NULL or the
96 processing at one of the locations specified failed. Check the
97 error stack to find out the reason.
98 1 The operation succeeded.
100
102 ssl(3), SSL_CTX_set_client_CA_list(3), SSL_get_client_CA_list(3),
103 SSL_CTX_use_certificate(3), SSL_CTX_add_extra_chain_cert(3),
104 SSL_CTX_set_cert_store(3)
1051.0.2o 2020-01-28 SSL_CTX_load_verify_locations(3)