CTLOG_STORE_new.3ssl man page

CTLOG_STORE_new, CTLOG_STORE_free, CTLOG_STORE_load_default_file, CTLOG_STORE_load_file — Create and populate a Certificate Transparency log list


 #include <openssl/ct.h>

 void CTLOG_STORE_free(CTLOG_STORE *store);

 int CTLOG_STORE_load_default_file(CTLOG_STORE *store);
 int CTLOG_STORE_load_file(CTLOG_STORE *store, const char *file);


A CTLOG_STORE is a container for a list of CTLOGs (Certificate Transparency logs). The list can be loaded from one or more files and then searched by LogID (see RFC 6962, Section 3.2, for the definition of a LogID).

CTLOG_STORE_new() creates an empty list of CT logs. This is then populated by CTLOG_STORE_load_default_file() or CTLOG_STORE_load_file(). CTLOG_STORE_load_default_file() loads from the default file, which is named "ct_log_list.cnf" in OPENSSLDIR (see the output of version). This can be overridden using an environment variable named "CTLOG_FILE". CTLOG_STORE_load_file() loads from a caller-specified file path instead. Both of these functions append any loaded CT logs to the CTLOG_STORE.

The expected format of the file is:


 description = Log 1
 key = <base64-encoded DER SubjectPublicKeyInfo here>

 description = Log 2
 key = <base64-encoded DER SubjectPublicKeyInfo here>

Once a CTLOG_STORE is no longer required, it should be passed to CTLOG_STORE_free(). This will delete all of the CTLOGs stored within, along with the CTLOG_STORE itself.


If there are any invalid CT logs in a file, they are skipped and the remaining valid logs will still be added to the CTLOG_STORE. A CT log will be considered invalid if it is missing a "key" or "description" field.

Return Values

Both CTLOG_STORE_load_default_file and CTLOG_STORE_load_file return 1 if all CT logs in the file are successfully parsed and loaded, 0 otherwise.

See Also

ct(3), CTLOG_STORE_get0_log_by_id(3), SSL_CTX_set_ctlog_list_file(3)


These functions were added in OpenSSL 1.1.0.


2017-03-06 1.1.0e OpenSSL