CURLOPT_SSL_CTX_DATA(3)

CURLOPT_SSL_CTX_DATA(3curl_easy_setopt optionCURLOPT_SSL_CTX_DATA(3)

NAME

     CURLOPT_SSL_CTX_DATA -  custom  pointer  passed  to  ssl_ctx
     callback

SYNOPSIS

     #include <curl/curl.h>

     CURLcode           curl_easy_setopt(CURL            *handle,
     CURLOPT_SSL_CTX_DATA, void *pointer);

DESCRIPTION

     Data pointer to pass to the ssl context callback set by  the
     option  CURLOPT_SSL_CTX_FUNCTION(3),  this  is  the  pointer
     you'll get as third parameter.

DEFAULT

     NULL

PROTOCOLS

     All TLS based protocols: HTTPS, FTPS,  IMAPS,  POP3S,  SMTPS
     etc.

EXAMPLE

     /* OpenSSL specific */

     #include <openssl/ssl.h>
     #include <curl/curl.h>
     #include <stdio.h>

     static CURLcode sslctx_function(CURL *curl, void *sslctx, void *parm)
     {
       X509_STORE *store;
       X509 *cert=NULL;
       BIO *bio;
       char *mypem = (char *)parm;
       /* get a BIO */
       bio=BIO_new_mem_buf(mypem, -1);
       /* use it to read the PEM formatted certificate from memory into an
        * X509 structure that SSL can use
        */
       PEM_read_bio_X509(bio, &cert, 0, NULL);
       if(cert == NULL)
         printf("PEM_read_bio_X509 failed...\n");

       /* get a pointer to the X509 certificate store (which may be empty) */
       store=SSL_CTX_get_cert_store((SSL_CTX *)sslctx);

       /* add our certificate to this store */
       if(X509_STORE_add_cert(store, cert)==0)
         printf("error adding certificate\n");

       /* decrease reference counts */

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CURLOPT_SSL_CTX_DATA(3curl_easy_setopt optionCURLOPT_SSL_CTX_DATA(3)

       X509_free(cert);
       BIO_free(bio);

       /* all set to go */
       return CURLE_OK;
     }

     int main(void)
     {
       CURL * ch;
       CURLcode rv;
       char *mypem = /* example CA cert PEM - shortened */
         "-----BEGIN CERTIFICATE-----\n"
         "MIIHPTCCBSWgAwIBAgIBADANBgkqhkiG9w0BAQQFADB5MRAwDgYDVQQKEwdSb290\n"
         "IENBMR4wHAYDVQQLExVodHRwOi8vd3d3LmNhY2VydC5vcmcxIjAgBgNVBAMTGUNB\n"
         "IENlcnQgU2lnbmluZyBBdXRob3JpdHkxITAfBgkqhkiG9w0BCQEWEnN1cHBvcnRA\n"
         "Y2FjZXJ0Lm9yZzAeFw0wMzAzMzAxMjI5NDlaFw0zMzAzMjkxMjI5NDlaMHkxEDAO\n"
         "GCSNe9FINSkYQKyTYOGWhlC0elnYjyELn8+CkcY7v2vcB5G5l1YjqrZslMZIBjzk\n"
         "zk6q5PYvCdxTby78dOs6Y5nCpqyJvKeyRKANihDjbPIky/qbn3BHLt4Ui9SyIAmW\n"
         "omTxJBzcoTWcFbLUvFUufQb1nA5V9FrWk9p2rSVzTMVD\n"
         "-----END CERTIFICATE-----\n";

       rv=curl_global_init(CURL_GLOBAL_ALL);
       ch=curl_easy_init();
       rv=curl_easy_setopt(ch, CURLOPT_SSLCERTTYPE, "PEM");
       rv=curl_easy_setopt(ch, CURLOPT_SSL_VERIFYPEER, 1L);
       rv=curl_easy_setopt(ch, CURLOPT_URL, "https://www.example.com/");

       /* Retrieve page using cacerts' certificate -> will succeed
        * load the certificate by installing a function doing the necessary
        * "modifications" to the SSL CONTEXT just before link init
        */
       rv=curl_easy_setopt(ch, CURLOPT_SSL_CTX_FUNCTION, *sslctx_function);
       rv=curl_easy_setopt(ch, CURLOPT_SSL_CTX_DATA, mypem);
       rv=curl_easy_perform(ch);
       if(rv==CURLE_OK)
         printf("*** transfer succeeded ***\n");
       else
         printf("*** transfer failed ***\n");

       curl_easy_cleanup(ch);
       curl_global_cleanup();
       return rv;
     }

AVAILABILITY

     Added  in  7.11.0  for  OpenSSL.   Added   in   7.42.0   for
     wolfSSL/CyaSSL. Other SSL backends not supported.

RETURN VALUE

     CURLE_OK if supported; or an error such as:

libcurl 7.58.0      Last change: May 31, 2017                   2

CURLOPT_SSL_CTX_DATA(3curl_easy_setopt optionCURLOPT_SSL_CTX_DATA(3)

     CURLE_NOT_BUILT_IN - Not supported by the SSL backend

     CURLE_UNKNOWN_OPTION

SEE ALSO

     CURLOPT_SSL_CTX_FUNCTION(3), CURLOPT_SSLVERSION(3),

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