gnutls_x509_crt_get_issuer_unique_id — API function


#include <gnutls/x509.h>

int gnutls_x509_crt_get_issuer_unique_id(gnutls_x509_crt_t crt, char * buf, size_t * buf_size);


gnutls_x509_crt_t crt

Holds the certificate

char * buf

user allocated memory buffer, will hold the unique id

size_t * buf_size

size of user allocated memory buffer (on input), will hold actual size of the unique ID on return.


This function will extract the issuerUniqueID value (if present) for the given certificate.

If the user allocated memory buffer is not large enough to hold the full subjectUniqueID, then a GNUTLS_E_SHORT_MEMORY_BUFFER error will be returned, and buf_size will be set to the actual length.

This function had a bug prior to 3.4.8 that prevented the setting of NULL  buf to discover the  buf_size . To use this function safely with the older versions the  buf must be a valid buffer that can hold at least a single byte if  buf_size is zero.


GNUTLS_E_SUCCESS on success, otherwise a negative error code.



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3.6.9 gnutls