X509_STORE_CTX_new.3ossl - Man Page

X509_STORE_CTX initialisation

Synopsis

 #include <openssl/x509_vfy.h>

 X509_STORE_CTX *X509_STORE_CTX_new_ex(OSSL_LIB_CTX *libctx, const char *propq);
 X509_STORE_CTX *X509_STORE_CTX_new(void);
 void X509_STORE_CTX_cleanup(X509_STORE_CTX *ctx);
 void X509_STORE_CTX_free(X509_STORE_CTX *ctx);

 int X509_STORE_CTX_init(X509_STORE_CTX *ctx, X509_STORE *trust_store,
                         X509 *target, STACK_OF(X509) *untrusted);

 void X509_STORE_CTX_set0_trusted_stack(X509_STORE_CTX *ctx, STACK_OF(X509) *sk);

 void X509_STORE_CTX_set_cert(X509_STORE_CTX *ctx, X509 *target);
 void X509_STORE_CTX_set0_crls(X509_STORE_CTX *ctx, STACK_OF(X509_CRL) *sk);

 X509_VERIFY_PARAM *X509_STORE_CTX_get0_param(const X509_STORE_CTX *ctx);
 void X509_STORE_CTX_set0_param(X509_STORE_CTX *ctx, X509_VERIFY_PARAM *param);

 STACK_OF(X509)* X509_STORE_CTX_get0_untrusted(const X509_STORE_CTX *ctx);
 void X509_STORE_CTX_set0_untrusted(X509_STORE_CTX *ctx, STACK_OF(X509) *sk);

 int X509_STORE_CTX_get_num_untrusted(const X509_STORE_CTX *ctx);
 STACK_OF(X509) *X509_STORE_CTX_get0_chain(const X509_STORE_CTX *ctx);
 void X509_STORE_CTX_set0_verified_chain(X509_STORE_CTX *ctx, STACK_OF(X509) *chain);

 int X509_STORE_CTX_set_default(X509_STORE_CTX *ctx, const char *name);
 typedef int (*X509_STORE_CTX_verify_fn)(X509_STORE_CTX *);
 void X509_STORE_CTX_set_verify(X509_STORE_CTX *ctx, X509_STORE_CTX_verify_fn verify);

Description

These functions initialise an X509_STORE_CTX structure for subsequent use by X509_verify_cert(3) or X509_STORE_CTX_verify(3).

X509_STORE_CTX_new_ex() returns a newly initialised X509_STORE_CTX structure associated with the specified library context libctx and property query string propq. Any cryptographic algorithms fetched while performing processing with the X509_STORE_CTX will use that library context and property query string.

X509_STORE_CTX_new() is the same as X509_STORE_CTX_new_ex() except that the default library context and a NULL property query string are used.

X509_STORE_CTX_cleanup() internally cleans up an X509_STORE_CTX structure. It is used by X509_STORE_CTX_init() and X509_STORE_CTX_free().

X509_STORE_CTX_free() completely frees up ctx. After this call ctx is no longer valid. If ctx is NULL nothing is done.

It must be called before each call to X509_verify_cert(3) or X509_STORE_CTX_verify(3), i.e., a context is only good for one verification. If you want to verify a further certificate or chain with the same ctx then you must call X509_STORE_CTX_init() again. The trusted certificate store is set to trust_store of type X509_STORE. This may be NULL because there are no trusted certificates or because they are provided simply as a list using X509_STORE_CTX_set0_trusted_stack(). The certificate to be verified is set to target, and a list of additional certificates may be provided in untrusted, which will be untrusted but may be used to build the chain. Each of the trust_store, target and untrusted parameters can be NULL. Yet note that X509_verify_cert(3) and X509_STORE_CTX_verify(3) will need a verification target. This can also be set using X509_STORE_CTX_set_cert(). For X509_STORE_CTX_verify(3), which takes by default the first element of the list of untrusted certificates as its verification target, this can be also set indirectly using X509_STORE_CTX_set0_untrusted().

X509_STORE_CTX_set0_trusted_stack() sets the set of trusted certificates of ctx to sk. This is an alternative way of specifying trusted certificates instead of using an X509_STORE where its complexity is not needed or to make sure that only the given set sk of certificates are trusted.

X509_STORE_CTX_set_cert() sets the target certificate to be verified in ctx to target.

X509_STORE_CTX_set0_verified_chain() sets the validated chain to chain. Ownership of the chain is transferred to ctx, and so it should not be free'd by the caller.

X509_STORE_CTX_get0_chain() returns the internal pointer used by the ctx that contains the constructed (output) chain.

X509_STORE_CTX_set0_crls() sets a set of CRLs to use to aid certificate verification to sk. These CRLs will only be used if CRL verification is enabled in the associated X509_VERIFY_PARAM structure. This might be used where additional “useful” CRLs are supplied as part of a protocol, for example in a PKCS#7 structure.

X509_STORE_CTX_get0_param() retrieves an internal pointer to the verification parameters associated with ctx.

X509_STORE_CTX_set0_param() sets the internal verification parameter pointer to param. After this call param should not be used.

X509_STORE_CTX_get0_untrusted() retrieves an internal pointer to the stack of untrusted certificates associated with ctx.

X509_STORE_CTX_set0_untrusted() sets the internal pointer to the stack of untrusted certificates associated with ctx to sk. X509_STORE_CTX_verify() will take the first element, if any, as its default target if the target certificate is not set explicitly.

X509_STORE_CTX_get_num_untrusted() returns the number of untrusted certificates that were used in building the chain. This is can be used after calling X509_verify_cert(3) and similar functions. With X509_STORE_CTX_verify(3), this does not count the first chain element.

X509_STORE_CTX_get0_chain() returns the internal pointer used by the ctx that contains the validated chain.

Details of the chain building and checking process are described in “Certification Path Building” in openssl-verification-options(1) and “Certification Path Validation” in openssl-verification-options(1).

X509_STORE_CTX_set0_verified_chain() sets the validated chain used by ctx to be chain. Ownership of the chain is transferred to ctx, and so it should not be free'd by the caller.

X509_STORE_CTX_set_default() looks up and sets the default verification method to name. This uses the function X509_VERIFY_PARAM_lookup() to find an appropriate set of parameters from the purpose identifier name. Currently defined purposes are sslclient, sslserver, nssslserver, smimesign, smimeencrypt, crlsign, ocsphelper, timestampsign, and any.

X509_STORE_CTX_set_verify() provides the capability for overriding the default verify function. This function is responsible for verifying chain signatures and expiration times.

A verify function is defined as an X509_STORE_CTX_verify type which has the following signature:

 int (*verify)(X509_STORE_CTX *);

This function should receive the current X509_STORE_CTX as a parameter and return 1 on success or 0 on failure.

Notes

The certificates and CRLs in a store are used internally and should not be freed up until after the associated X509_STORE_CTX is freed.

Bugs

The certificates and CRLs in a context are used internally and should not be freed up until after the associated X509_STORE_CTX is freed. Copies should be made or reference counts increased instead.

Return Values

X509_STORE_CTX_new() returns a newly allocated context or NULL if an error occurred.

X509_STORE_CTX_init() returns 1 for success or 0 if an error occurred.

X509_STORE_CTX_get0_param() returns a pointer to an X509_VERIFY_PARAM structure or NULL if an error occurred.

X509_STORE_CTX_cleanup(), X509_STORE_CTX_free(), X509_STORE_CTX_set0_trusted_stack(), X509_STORE_CTX_set_cert(), X509_STORE_CTX_set0_crls() and X509_STORE_CTX_set0_param() do not return values.

X509_STORE_CTX_set_default() returns 1 for success or 0 if an error occurred.

X509_STORE_CTX_get_num_untrusted() returns the number of untrusted certificates used.

See Also

X509_verify_cert(3), X509_STORE_CTX_verify(3), X509_VERIFY_PARAM_set_flags(3)

History

The X509_STORE_CTX_set0_crls() function was added in OpenSSL 1.0.0. The X509_STORE_CTX_get_num_untrusted() function was added in OpenSSL 1.1.0. The X509_STORE_CTX_new_ex() function was added in OpenSSL 3.0.

There is no need to call X509_STORE_CTX_cleanup() explicitly since OpenSSL 3.0.

Referenced By

migration_guide.7ossl(7), X509_verify_cert.3ossl(3).

The man pages X509_STORE_CTX_cleanup.3ossl(3), X509_STORE_CTX_free.3ossl(3), X509_STORE_CTX_get0_chain.3ossl(3), X509_STORE_CTX_get0_param.3ossl(3), X509_STORE_CTX_get0_untrusted.3ossl(3), X509_STORE_CTX_get_num_untrusted.3ossl(3), X509_STORE_CTX_init.3ossl(3), X509_STORE_CTX_new_ex.3ossl(3), X509_STORE_CTX_set0_crls.3ossl(3), X509_STORE_CTX_set0_param.3ossl(3), X509_STORE_CTX_set0_trusted_stack.3ossl(3), X509_STORE_CTX_set0_untrusted.3ossl(3), X509_STORE_CTX_set0_verified_chain.3ossl(3), X509_STORE_CTX_set_cert.3ossl(3), X509_STORE_CTX_set_default.3ossl(3), X509_STORE_CTX_set_verify.3ossl(3) and X509_STORE_CTX_verify_fn.3ossl(3) are aliases of X509_STORE_CTX_new.3ossl(3).

2021-09-09 3.0.0 OpenSSL