rc_avpair_gen(3) Radius client library rc_avpair_gen(3)

rc_avpair_gen - Decode a raw RADIUS attribute buffer into a VALUE_PAIR list.

#include <radcli/>

VALUE_PAIR * rc_avpair_gen(
    rc_handle const      *rh,
    VALUE_PAIR           *pair,
    unsigned char const  *ptr,
    int                   length,
    uint32_t              vendorspec
);

This is a low-level function retained for ABI compatibility with freeradius-client and radiusclient-ng. Application code should not call it directly; build requests with rc_avpair_add() and send them with rc_auth() or rc_acct(), which handle wire encoding and decoding internally.

Decodes the attribute/value region of a received RADIUS packet (the bytes that follow the 20-byte fixed header) into a linked list of VALUE_PAIR structures. Unknown attributes are logged and skipped; they are not a hard error.

a handle to parsed configuration (used for dictionary lookups).
optional existing VALUE_PAIR list to append decoded attributes to; pass NULL to start a fresh list.
pointer to the start of the attribute data region.
number of bytes in the attribute region.
vendor PEN when decoding a vendor-specific sub-attribute block; pass 0 for top-level packet attributes.

Avoid using this structure directly. Use rc_avpair_get_uint32() for integer/IPv4/date values, rc_avpair_get_in6() for IPv6 addresses and prefixes, rc_avpair_get_raw() for string/binary values, and rc_avpair_get_attr() to read the attribute type and ID. To iterate the list use rc_avpair_next(). Free the entire list with rc_avpair_free().


struct rc_value_pair {
  char                   name[RC_NAME_LENGTH+1];      // attribute name if known. 
  uint64_t               attribute; // attribute numeric value of type rc_attr_id including vendor; use VENDOR() and ATTRID() to separate. 
  rc_attr_type           type;      // attribute type. 
  uint32_t               lvalue;    // attribute value if type is PW_TYPE_INTEGER, PW_TYPE_DATE or PW_TYPE_IPADDR. 
  char                   strvalue[AUTH_STRING_LEN+1];  // contains attribute value in other cases. 
  struct rc_value_pair  *next;
  char                   pad[32];       // unused pad 
};

head of the (possibly extended) VALUE_PAIR list, or NULL on a hard decode error (malformed length field, allocation failure).

rc_aaa(3), rc_aaa_ctx(3), rc_aaa_ctx_free(3), rc_aaa_ctx_get_secret(3), rc_aaa_ctx_get_vector(3), rc_aaa_ctx_server(3), rc_acct(3), rc_acct_async(3), rc_acct_proxy(3), rc_add_config(3), rc_apply_config(3), rc_auth(3), rc_auth_proxy(3), rc_avpair_add(3), rc_avpair_assign(3), rc_avpair_copy(3), rc_avpair_free(3), rc_avpair_get(3), rc_avpair_get_attr(3), rc_avpair_get_in6(3), rc_avpair_get_raw(3), rc_avpair_get_uint32(3), rc_avpair_insert(3), rc_avpair_log(3), rc_avpair_new(3), rc_avpair_next(3), rc_avpair_parse(3), rc_avpair_remove(3), rc_avpair_tostr(3), rc_buildreq(3), rc_check(3), rc_conf_int(3), rc_conf_srv(3), rc_conf_str(3), rc_config_free(3), rc_config_init(3), rc_destroy(3), rc_dict_addattr(3), rc_dict_addval(3), rc_dict_addvend(3), rc_dict_findattr(3), rc_dict_findval(3), rc_dict_findvend(3), rc_dict_free(3), rc_dict_getattr(3), rc_dict_getval(3), rc_dict_getvend(3), rc_find_server_addr(3), rc_get_socket_type(3), rc_new(3), rc_read_config(3), rc_read_dictionary(3), rc_read_dictionary_from_buffer(3), rc_send_server(3), rc_test_config(3)

2026-08-19 radcli