SSL_CTX_get0_param.3ossl - Man Page

get and set verification parameters


 #include <openssl/ssl.h>

 X509_VERIFY_PARAM *SSL_CTX_get0_param(SSL_CTX *ctx);
 X509_VERIFY_PARAM *SSL_get0_param(SSL *ssl);
 int SSL_CTX_set1_param(SSL_CTX *ctx, X509_VERIFY_PARAM *vpm);
 int SSL_set1_param(SSL *ssl, X509_VERIFY_PARAM *vpm);

 int SSL_CTX_set_purpose(SSL_CTX *ctx, int purpose);
 int SSL_set_purpose(SSL *ssl, int purpose);

 int SSL_CTX_set_trust(SSL_CTX *ctx, int trust);
 int SSL_set_trust(SSL *ssl, int trust);


SSL_CTX_get0_param() and SSL_get0_param() retrieve an internal pointer to the verification parameters for ctx or ssl respectively. The returned pointer must not be freed by the calling application.

SSL_CTX_set1_param() and SSL_set1_param() set the verification parameters to vpm for ctx or ssl.

The functions SSL_CTX_set_purpose() and SSL_set_purpose() are shorthands which set the purpose parameter on the verification parameters object. These functions are equivalent to calling X509_VERIFY_PARAM_set_purpose() directly.

The functions SSL_CTX_set_trust() and SSL_set_trust() are similarly shorthands which set the trust parameter on the verification parameters object. These functions are equivalent to calling X509_VERIFY_PARAM_set_trust() directly.


Typically parameters are retrieved from an SSL_CTX or SSL structure using SSL_CTX_get0_param() or SSL_get0_param() and an application modifies them to suit its needs: for example to add a hostname check.

Return Values

SSL_CTX_get0_param() and SSL_get0_param() return a pointer to an X509_VERIFY_PARAM structure.

SSL_CTX_set1_param(), SSL_set1_param(), SSL_CTX_set_purpose(), SSL_set_purpose(), SSL_CTX_set_trust() and SSL_set_trust() return 1 for success and 0 for failure.


Check hostname matches "" in peer certificate:

 X509_VERIFY_PARAM *vpm = SSL_get0_param(ssl);
 X509_VERIFY_PARAM_set1_host(vpm, "", 0);

See Also

ssl(7), X509_VERIFY_PARAM_set_flags(3)


These functions were added in OpenSSL 1.0.2.

Referenced By


The man pages SSL_CTX_set1_param.3ossl(3), SSL_CTX_set_purpose.3ossl(3), SSL_CTX_set_trust.3ossl(3), SSL_get0_param.3ossl(3), SSL_set1_param.3ossl(3), SSL_set_purpose.3ossl(3) and SSL_set_trust.3ossl(3) are aliases of SSL_CTX_get0_param.3ossl(3).

2024-02-09 3.2.1 OpenSSL