/usr/man/cat.3/X509_NAME_get_entry.3

X509_NAME_get_index_by_NID(3)OpenSSLX509_NAME_get_index_by_NID(3)

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

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X509_NAME_get_index_by_NID(3)OpenSSLX509_NAME_get_index_by_NID(3)

     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 lastpos = -1;
      X509_NAME_ENTRY *e;

      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.

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X509_NAME_get_index_by_NID(3)OpenSSLX509_NAME_get_index_by_NID(3)

     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

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See also X509_NAME_entry_count(3)
See also X509_NAME_get_index_by_NID(3)
See also X509_NAME_get_index_by_OBJ(3)
See also X509_NAME_get_text_by_NID(3)
See also X509_NAME_get_text_by_OBJ(3)