X509_NAME_get_index_by_NID(3SSL)             OpenSSL             X509_NAME_get_index_by_NID(3SSL)



NAME
       X509_NAME_get_index_by_NID, X509_NAME_get_index_by_OBJ, X509_NAME_get_entry,
       X509_NAME_entry_count, X509_NAME_get_text_by_NID, X509_NAME_get_text_by_OBJ - X509_NAME
       lookup and enumeration functions

SYNOPSIS
        #include <openssl/x509.h>

        int X509_NAME_get_index_by_NID(X509_NAME *name,int nid,int lastpos);
        int X509_NAME_get_index_by_OBJ(X509_NAME *name,ASN1_OBJECT *obj, int lastpos);

        int X509_NAME_entry_count(X509_NAME *name);
        X509_NAME_ENTRY *X509_NAME_get_entry(X509_NAME *name, int loc);

        int X509_NAME_get_text_by_NID(X509_NAME *name, int nid, char *buf,int len);
        int X509_NAME_get_text_by_OBJ(X509_NAME *name, ASN1_OBJECT *obj, char *buf,int len);

DESCRIPTION
       These functions allow an X509_NAME structure to be examined. The X509_NAME structure is
       the same as the Name type defined in RFC2459 (and elsewhere) and used for example in
       certificate subject and issuer names.

       X509_NAME_get_index_by_NID() and X509_NAME_get_index_by_OBJ() retrieve the next index
       matching nid or obj after lastpos. lastpos should initially be set to -1. If there are no
       more entries -1 is returned.  If nid is invalid (doesn't correspond to a valid OID) then
       -2 is returned.

       X509_NAME_entry_count() returns the total number of entries in name.

       X509_NAME_get_entry() retrieves the X509_NAME_ENTRY from name corresponding to index loc.
       Acceptable values for loc run from 0 to (X509_NAME_entry_count(name) - 1). The value
       returned is an internal pointer which must not be freed.

       X509_NAME_get_text_by_NID(), X509_NAME_get_text_by_OBJ() retrieve the "text" from the
       first entry in name which matches nid or obj, if no such entry exists -1 is returned. At
       most len bytes will be written and the text written to buf will be null terminated. The
       length of the output string written is returned excluding the terminating null. If buf is
       <NULL> then the amount of space needed in buf (excluding the final null) is returned.

NOTES
       X509_NAME_get_text_by_NID() and X509_NAME_get_text_by_OBJ() are legacy functions which
       have various limitations which make them of minimal use in practice. They can only find
       the first matching entry and will copy the contents of the field verbatim: this can be
       highly confusing if the target is a muticharacter string type like a BMPString or a
       UTF8String.

       For a more general solution X509_NAME_get_index_by_NID() or X509_NAME_get_index_by_OBJ()
       should be used followed by X509_NAME_get_entry() on any matching indices and then the
       various X509_NAME_ENTRY utility functions on the result.

       The list of all relevant NID_* and OBJ_* codes can be found in the source code header
       files <openssl/obj_mac.h> and/or <openssl/objects.h>.

       Applications which could pass invalid NIDs to X509_NAME_get_index_by_NID() should check
       for the return value of -2. Alternatively the NID validity can be determined first by
       checking OBJ_nid2obj(nid) is not NULL.

EXAMPLES
       Process all entries:

        int i;
        X509_NAME_ENTRY *e;

        for (i = 0; i < X509_NAME_entry_count(nm); i++)
               {
               e = X509_NAME_get_entry(nm, i);
               /* Do something with e */
               }

       Process all commonName entries:

        int loc;
        X509_NAME_ENTRY *e;

        loc = -1;
        for (;;)
               {
               lastpos = X509_NAME_get_index_by_NID(nm, NID_commonName, lastpos);
               if (lastpos == -1)
                       break;
               e = X509_NAME_get_entry(nm, lastpos);
               /* Do something with e */
               }

RETURN VALUES
       X509_NAME_get_index_by_NID() and X509_NAME_get_index_by_OBJ() return the index of the next
       matching entry or -1 if not found.  X509_NAME_get_index_by_NID() can also return -2 if the
       supplied NID is invalid.

       X509_NAME_entry_count() returns the total number of entries.

       X509_NAME_get_entry() returns an X509_NAME pointer to the requested entry or NULL if the
       index is invalid.

SEE ALSO
       ERR_get_error(3), d2i_X509_NAME(3)

HISTORY
       TBA



1.0.1t                                      2016-05-03           X509_NAME_get_index_by_NID(3SSL)