CURLOPT_ISSUERCERT_BLOB(3) Library Functions Manual
NAME
CURLOPT_ISSUERCERT_BLOB - issuer SSL certificate from memory blob
SYNOPSIS
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_ISSUERCERT_BLOB,
struct curl_blob *stblob);
DESCRIPTION
Pass a pointer to a curl_blob structure, which contains information
(pointer and size) about a memory block with binary data of a CA
certificate in PEM format. If the option is set, an additional check
against the peer certificate is performed to verify the issuer is
indeed the one associated with the certificate provided by the option.
This additional check is useful in multi-level PKI where one needs to
enforce that the peer certificate is from a specific branch of the
tree.
This option should be used in combination with the
CURLOPT_SSL_VERIFYPEER(3) option. Otherwise, the result of the check is
not considered as failure.
A specific error code (CURLE_SSL_ISSUER_ERROR) is defined with the
option, which is returned if the setup of the SSL/TLS session has
failed due to a mismatch with the issuer of peer certificate
(C) has to be set too for the check to fail).
If the blob is initialized with the flags member of struct curl_blob
set to CURL_BLOB_COPY, the application does not have to keep the buffer
around after setting this.
This option is an alternative to CURLOPT_ISSUERCERT(3) which instead
expects a filename as input.
DEFAULT
NULL
PROTOCOLS
This functionality affects all TLS based protocols: HTTPS, FTPS, IMAPS,
POP3S, SMTPS etc.
This option works only with the following TLS backends: OpenSSL
EXAMPLE
extern char *certificateData;
extern size_t filesize;
int main(void)
{
CURL *curl = curl_easy_init();
if(curl) {
CURLcode res;
struct curl_blob blob;
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
blob.data = certificateData;
blob.len = filesize;
blob.flags = CURL_BLOB_COPY;
curl_easy_setopt(curl, CURLOPT_ISSUERCERT_BLOB, &blob);
res = curl_easy_perform(curl);
curl_easy_cleanup(curl);
}
}
AVAILABILITY
Added in curl 7.71.0
RETURN VALUE
Returns CURLE_OK if the option is supported, CURLE_UNKNOWN_OPTION if
not, or CURLE_OUT_OF_MEMORY if there was insufficient heap space.
SEE ALSO
CURLOPT_CRLFILE(3), CURLOPT_ISSUERCERT(3), CURLOPT_SSL_VERIFYHOST(3),
CURLOPT_SSL_VERIFYPEER(3)
libcurl 2024-08-05 CURLOPT_ISSUERCERT_BLOB(3)
curl 8.9.1 - Generated Fri Aug 9 13:11:10 CDT 2024