diff options
Diffstat (limited to 'contrib/bind9/lib/lwres/getipnode.c')
| -rw-r--r-- | contrib/bind9/lib/lwres/getipnode.c | 109 |
1 files changed, 107 insertions, 2 deletions
diff --git a/contrib/bind9/lib/lwres/getipnode.c b/contrib/bind9/lib/lwres/getipnode.c index 9b1a07bdda7b..46eed144ad03 100644 --- a/contrib/bind9/lib/lwres/getipnode.c +++ b/contrib/bind9/lib/lwres/getipnode.c @@ -15,7 +15,110 @@ * PERFORMANCE OF THIS SOFTWARE. */ -/* $Id: getipnode.c,v 1.30.2.4.2.6 2005/04/29 00:03:32 marka Exp $ */ +/* $Id: getipnode.c,v 1.37.18.3 2005/04/29 00:17:18 marka Exp $ */ + +/*! \file */ + +/** + * These functions perform thread safe, protocol independent + * nodename-to-address and address-to-nodename translation as defined in + * RFC2553. This use a struct hostent which is defined in namedb.h: + * + * \code + * struct hostent { + * char *h_name; // official name of host + * char **h_aliases; // alias list + * int h_addrtype; // host address type + * int h_length; // length of address + * char **h_addr_list; // list of addresses from name server + * }; + * #define h_addr h_addr_list[0] // address, for backward compatibility + * \endcode + * + * The members of this structure are: + * + * \li h_name: + * The official (canonical) name of the host. + * + * \li h_aliases: + * A NULL-terminated array of alternate names (nicknames) for the + * host. + * + * \li h_addrtype: + * The type of address being returned - usually PF_INET or + * PF_INET6. + * + * \li h_length: + * The length of the address in bytes. + * + * \li h_addr_list: + * A NULL terminated array of network addresses for the host. Host + * addresses are returned in network byte order. + * + * lwres_getipnodebyname() looks up addresses of protocol family af for + * the hostname name. The flags parameter contains ORed flag bits to + * specify the types of addresses that are searched for, and the types of + * addresses that are returned. The flag bits are: + * + * \li #AI_V4MAPPED: + * This is used with an af of #AF_INET6, and causes IPv4 addresses + * to be returned as IPv4-mapped IPv6 addresses. + * + * \li #AI_ALL: + * This is used with an af of #AF_INET6, and causes all known + * addresses (IPv6 and IPv4) to be returned. If #AI_V4MAPPED is + * also set, the IPv4 addresses are return as mapped IPv6 + * addresses. + * + * \li #AI_ADDRCONFIG: + * Only return an IPv6 or IPv4 address if here is an active + * network interface of that type. This is not currently + * implemented in the BIND 9 lightweight resolver, and the flag is + * ignored. + * + * \li #AI_DEFAULT: + * This default sets the #AI_V4MAPPED and #AI_ADDRCONFIG flag bits. + * + * lwres_getipnodebyaddr() performs a reverse lookup of address src which + * is len bytes long. af denotes the protocol family, typically PF_INET + * or PF_INET6. + * + * lwres_freehostent() releases all the memory associated with the struct + * hostent pointer. Any memory allocated for the h_name, h_addr_list + * and h_aliases is freed, as is the memory for the hostent structure + * itself. + * + * \section getipnode_return Return Values + * + * If an error occurs, lwres_getipnodebyname() and + * lwres_getipnodebyaddr() set *error_num to an appropriate error code + * and the function returns a NULL pointer. The error codes and their + * meanings are defined in \link netdb.h <lwres/netdb.h>\endlink: + * + * \li #HOST_NOT_FOUND: + * No such host is known. + * + * \li #NO_ADDRESS: + * The server recognised the request and the name but no address + * is available. Another type of request to the name server for + * the domain might return an answer. + * + * \li #TRY_AGAIN: + * A temporary and possibly transient error occurred, such as a + * failure of a server to respond. The request may succeed if + * retried. + * + * \li #NO_RECOVERY: + * An unexpected failure occurred, and retrying the request is + * pointless. + * + * lwres_hstrerror() translates these error codes to suitable error + * messages. + * + * \section getipnode_see See Also + * + * getaddrinfo.c, gethost.c, getnameinfo.c, herror.c, RFC2553 + */ #include <config.h> @@ -80,7 +183,7 @@ hostfromname(lwres_gabnresponse_t *name, int af); *** Public functions. ***/ -/* +/*! * AI_V4MAPPED + AF_INET6 * If no IPv6 address then a query for IPv4 and map returned values. * @@ -222,6 +325,7 @@ lwres_getipnodebyname(const char *name, int af, int flags, int *error_num) { return (he3); } +/*% performs a reverse lookup of address src which is len bytes long. af denotes the protocol family, typically #PF_INET or PF_INET6. */ struct hostent * lwres_getipnodebyaddr(const void *src, size_t len, int af, int *error_num) { struct hostent *he1, *he2; @@ -345,6 +449,7 @@ lwres_getipnodebyaddr(const void *src, size_t len, int af, int *error_num) { return (he1); } +/*% releases all the memory associated with the struct hostent pointer */ void lwres_freehostent(struct hostent *he) { char **cpp; |