X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fnss-myhostname%2Fnss-myhostname.c;h=a939bb267cbe1c2f8a2c10d53b101db7adc45829;hb=7a7d5db71f12ae6f3c055b88a85f6bc9305ea1c4;hp=6551ac9f320159697df9515f44629dce8521afb4;hpb=47efffc22badb20124dca5ed8c3b52911d71fc31;p=elogind.git diff --git a/src/nss-myhostname/nss-myhostname.c b/src/nss-myhostname/nss-myhostname.c index 6551ac9f3..a939bb267 100644 --- a/src/nss-myhostname/nss-myhostname.c +++ b/src/nss-myhostname/nss-myhostname.c @@ -30,66 +30,29 @@ #include #include -#include "addresses.h" +#include "local-addresses.h" #include "macro.h" - -/* Ensure that glibc's assert is used. We cannot use assert from macro.h, as - * libnss_myhostname will be linked into arbitrary programs which will, in turn - * attempt to write to the journal via log_dispatch() */ -#include +#include "nss-util.h" +#include "util.h" /* We use 127.0.0.2 as IPv4 address. This has the advantage over * 127.0.0.1 that it can be translated back to the local hostname. For * IPv6 we use ::1 which unfortunately will not translate back to the - * hostname but instead something like "localhost6" or so. */ + * hostname but instead something like "localhost" or so. */ #define LOCALADDRESS_IPV4 (htonl(0x7F000002)) #define LOCALADDRESS_IPV6 &in6addr_loopback #define LOOPBACK_INTERFACE "lo" -enum nss_status _nss_myhostname_gethostbyname4_r( - const char *name, - struct gaih_addrtuple **pat, - char *buffer, size_t buflen, - int *errnop, int *h_errnop, - int32_t *ttlp) _public_; - -enum nss_status _nss_myhostname_gethostbyname3_r( - const char *name, - int af, - struct hostent *host, - char *buffer, size_t buflen, - int *errnop, int *h_errnop, - int32_t *ttlp, - char **canonp) _public_; - -enum nss_status _nss_myhostname_gethostbyname2_r( - const char *name, - int af, - struct hostent *host, - char *buffer, size_t buflen, - int *errnop, int *h_errnop) _public_; +NSS_GETHOSTBYNAME_PROTOTYPES(myhostname); +NSS_GETHOSTBYADDR_PROTOTYPES(myhostname); -enum nss_status _nss_myhostname_gethostbyname_r( - const char *name, - struct hostent *host, - char *buffer, size_t buflen, - int *errnop, int *h_errnop) _public_; +static bool is_gateway(const char *hostname) { + assert(hostname); -enum nss_status _nss_myhostname_gethostbyaddr2_r( - const void* addr, socklen_t len, - int af, - struct hostent *host, - char *buffer, size_t buflen, - int *errnop, int *h_errnop, - int32_t *ttlp) _public_; - -enum nss_status _nss_myhostname_gethostbyaddr_r( - const void* addr, socklen_t len, - int af, - struct hostent *host, - char *buffer, size_t buflen, - int *errnop, int *h_errnop) _public_; + return streq(hostname, "gateway") || + streq(hostname, "gateway."); +} enum nss_status _nss_myhostname_gethostbyname4_r( const char *name, @@ -99,15 +62,15 @@ enum nss_status _nss_myhostname_gethostbyname4_r( int32_t *ttlp) { struct gaih_addrtuple *r_tuple, *r_tuple_prev = NULL; - _cleanup_free_ struct address *addresses = NULL; + _cleanup_free_ struct local_address *addresses = NULL; _cleanup_free_ char *hn = NULL; const char *canonical = NULL; - unsigned n_addresses = 0, n; + int n_addresses = 0, lo_ifi; uint32_t local_address_ipv4; - struct address *a; + struct local_address *a; size_t l, idx, ms; char *r_name; - int lo_ifi; + unsigned n; assert(name); assert(pat); @@ -121,6 +84,18 @@ enum nss_status _nss_myhostname_gethostbyname4_r( canonical = "localhost"; local_address_ipv4 = htonl(INADDR_LOOPBACK); + + } else if (is_gateway(name)) { + + n_addresses = local_gateways(NULL, 0, AF_UNSPEC, &addresses); + if (n_addresses <= 0) { + *errnop = ENOENT; + *h_errnop = HOST_NOT_FOUND; + return NSS_STATUS_NOTFOUND; + } + + canonical = "gateway"; + } else { hn = gethostname_malloc(); if (!hn) { @@ -136,8 +111,9 @@ enum nss_status _nss_myhostname_gethostbyname4_r( return NSS_STATUS_NOTFOUND; } - /* If this fails, n_addresses is 0. Which is fine */ - acquire_addresses(&addresses, &n_addresses); + n_addresses = local_addresses(NULL, 0, AF_UNSPEC, &addresses); + if (n_addresses < 0) + n_addresses = 0; canonical = hn; local_address_ipv4 = LOCALADDRESS_IPV4; @@ -184,7 +160,7 @@ enum nss_status _nss_myhostname_gethostbyname4_r( } /* Fourth, fill actual addresses in, but in backwards order */ - for (a = addresses + n_addresses - 1, n = 0; n < n_addresses; n++, a--) { + for (a = addresses + n_addresses - 1, n = 0; (int) n < n_addresses; n++, a--) { r_tuple = (struct gaih_addrtuple*) (buffer + idx); r_tuple->next = r_tuple_prev; r_tuple->name = r_name; @@ -208,13 +184,18 @@ enum nss_status _nss_myhostname_gethostbyname4_r( if (ttlp) *ttlp = 0; + /* Explicitly reset all error variables */ + *errnop = 0; + *h_errnop = NETDB_SUCCESS; + h_errno = 0; + return NSS_STATUS_SUCCESS; } static enum nss_status fill_in_hostent( const char *canonical, const char *additional, int af, - struct address *addresses, unsigned n_addresses, + struct local_address *addresses, unsigned n_addresses, uint32_t local_address_ipv4, struct hostent *result, char *buffer, size_t buflen, @@ -222,10 +203,9 @@ static enum nss_status fill_in_hostent( int32_t *ttlp, char **canonp) { - size_t l_canonical, l_additional, idx, ms; + size_t l_canonical, l_additional, idx, ms, alen; char *r_addr, *r_name, *r_aliases, *r_alias = NULL, *r_addr_list; - size_t alen; - struct address *a; + struct local_address *a; unsigned n, c; assert(canonical); @@ -234,7 +214,7 @@ static enum nss_status fill_in_hostent( assert(errnop); assert(h_errnop); - alen = PROTO_ADDRESS_SIZE(af); + alen = FAMILY_ADDRESS_SIZE(af); for (a = addresses, n = 0, c = 0; n < n_addresses; a++, n++) if (af == a->family) @@ -246,7 +226,7 @@ static enum nss_status fill_in_hostent( (additional ? ALIGN(l_additional+1) : 0) + sizeof(char*) + (additional ? sizeof(char*) : 0) + - (c > 0 ? c : 1) * ALIGN(alen)+ + (c > 0 ? c : 1) * ALIGN(alen) + (c > 0 ? c+1 : 2) * sizeof(char*); if (buflen < ms) { @@ -304,24 +284,18 @@ static enum nss_status fill_in_hostent( /* Fourth, add address pointer array */ r_addr_list = buffer + idx; if (c > 0) { - unsigned i = 0; - - for (a = addresses, n = 0; n < n_addresses; a++, n++) { - if (af != a->family) - continue; + unsigned i; - ((char**) r_addr_list)[i] = (r_addr + i*ALIGN(alen)); - i++; - } + for (i = 0; i < c; i++) + ((char**) r_addr_list)[i] = r_addr + i*ALIGN(alen); - assert(i == c); - ((char**) r_addr_list)[c] = NULL; - idx += (c+1)*sizeof(char*); + ((char**) r_addr_list)[i] = NULL; + idx += (c+1) * sizeof(char*); } else { ((char**) r_addr_list)[0] = r_addr; ((char**) r_addr_list)[1] = NULL; - idx += 2*sizeof(char*); + idx += 2 * sizeof(char*); } /* Verify the size matches */ @@ -339,6 +313,11 @@ static enum nss_status fill_in_hostent( if (canonp) *canonp = r_name; + /* Explicitly reset all error variables */ + *errnop = 0; + *h_errnop = NETDB_SUCCESS; + h_errno = 0; + return NSS_STATUS_SUCCESS; } @@ -351,11 +330,11 @@ enum nss_status _nss_myhostname_gethostbyname3_r( int32_t *ttlp, char **canonp) { - _cleanup_free_ struct address *addresses = NULL; + _cleanup_free_ struct local_address *addresses = NULL; const char *canonical, *additional = NULL; _cleanup_free_ char *hn = NULL; - uint32_t local_address_ipv4; - unsigned n_addresses = 0; + uint32_t local_address_ipv4 = 0; + int n_addresses = 0; assert(name); assert(host); @@ -375,6 +354,18 @@ enum nss_status _nss_myhostname_gethostbyname3_r( if (is_localhost(name)) { canonical = "localhost"; local_address_ipv4 = htonl(INADDR_LOOPBACK); + + } else if (is_gateway(name)) { + + n_addresses = local_gateways(NULL, 0, af, &addresses); + if (n_addresses <= 0) { + *errnop = ENOENT; + *h_errnop = HOST_NOT_FOUND; + return NSS_STATUS_NOTFOUND; + } + + canonical = "gateway"; + } else { hn = gethostname_malloc(); if (!hn) { @@ -389,7 +380,9 @@ enum nss_status _nss_myhostname_gethostbyname3_r( return NSS_STATUS_NOTFOUND; } - acquire_addresses(&addresses, &n_addresses); + n_addresses = local_addresses(NULL, 0, af, &addresses); + if (n_addresses < 0) + n_addresses = 0; canonical = hn; additional = n_addresses <= 0 && af == AF_INET6 ? "localhost" : NULL; @@ -408,39 +401,6 @@ enum nss_status _nss_myhostname_gethostbyname3_r( canonp); } -enum nss_status _nss_myhostname_gethostbyname2_r( - const char *name, - int af, - struct hostent *host, - char *buffer, size_t buflen, - int *errnop, int *h_errnop) { - - return _nss_myhostname_gethostbyname3_r( - name, - af, - host, - buffer, buflen, - errnop, h_errnop, - NULL, - NULL); -} - -enum nss_status _nss_myhostname_gethostbyname_r( - const char *name, - struct hostent *host, - char *buffer, size_t buflen, - int *errnop, int *h_errnop) { - - return _nss_myhostname_gethostbyname3_r( - name, - AF_UNSPEC, - host, - buffer, buflen, - errnop, h_errnop, - NULL, - NULL); -} - enum nss_status _nss_myhostname_gethostbyaddr2_r( const void* addr, socklen_t len, int af, @@ -451,10 +411,12 @@ enum nss_status _nss_myhostname_gethostbyaddr2_r( const char *canonical = NULL, *additional = NULL; uint32_t local_address_ipv4 = LOCALADDRESS_IPV4; - _cleanup_free_ struct address *addresses = NULL; + _cleanup_free_ struct local_address *addresses = NULL; _cleanup_free_ char *hn = NULL; - unsigned n_addresses = 0, n; - struct address *a; + int n_addresses = 0; + struct local_address *a; + bool additional_from_hostname = false; + unsigned n; assert(addr); assert(host); @@ -462,14 +424,19 @@ enum nss_status _nss_myhostname_gethostbyaddr2_r( assert(errnop); assert(h_errnop); - if (len != PROTO_ADDRESS_SIZE(af)) { + if (!IN_SET(af, AF_INET, AF_INET6)) { + *errnop = EAFNOSUPPORT; + *h_errnop = NO_DATA; + return NSS_STATUS_UNAVAIL; + } + + if (len != FAMILY_ADDRESS_SIZE(af)) { *errnop = EINVAL; *h_errnop = NO_RECOVERY; return NSS_STATUS_UNAVAIL; } if (af == AF_INET) { - if ((*(uint32_t*) addr) == LOCALADDRESS_IPV4) goto found; @@ -479,27 +446,41 @@ enum nss_status _nss_myhostname_gethostbyaddr2_r( goto found; } - } else if (af == AF_INET6) { + } else { + assert(af == AF_INET6); if (memcmp(addr, LOCALADDRESS_IPV6, 16) == 0) { - additional = "localhost"; + canonical = "localhost"; + additional_from_hostname = true; goto found; } + } - } else { - *errnop = EAFNOSUPPORT; - *h_errnop = NO_DATA; - return NSS_STATUS_UNAVAIL; + n_addresses = local_addresses(NULL, 0, AF_UNSPEC, &addresses); + if (n_addresses > 0) { + for (a = addresses, n = 0; (int) n < n_addresses; n++, a++) { + if (af != a->family) + continue; + + if (memcmp(addr, &a->address, FAMILY_ADDRESS_SIZE(af)) == 0) + goto found; + } } - acquire_addresses(&addresses, &n_addresses); + free(addresses); + addresses = NULL; - for (a = addresses, n = 0; n < n_addresses; n++, a++) { - if (af != a->family) - continue; + n_addresses = local_gateways(NULL, 0, AF_UNSPEC, &addresses); + if (n_addresses > 0) { + for (a = addresses, n = 0; (int) n < n_addresses; n++, a++) { + if (af != a->family) + continue; - if (memcmp(addr, &a->address, PROTO_ADDRESS_SIZE(af)) == 0) - goto found; + if (memcmp(addr, &a->address, FAMILY_ADDRESS_SIZE(af)) == 0) { + canonical = "gateway"; + goto found; + } + } } *errnop = ENOENT; @@ -508,7 +489,7 @@ enum nss_status _nss_myhostname_gethostbyaddr2_r( return NSS_STATUS_NOTFOUND; found: - if (!canonical) { + if (!canonical || (!additional && additional_from_hostname)) { hn = gethostname_malloc(); if (!hn) { *errnop = ENOMEM; @@ -516,7 +497,11 @@ found: return NSS_STATUS_TRYAGAIN; } - canonical = hn; + if (!canonical) + canonical = hn; + + if (!additional && additional_from_hostname) + additional = hn; } return fill_in_hostent( @@ -529,21 +514,7 @@ found: errnop, h_errnop, ttlp, NULL); - } -enum nss_status _nss_myhostname_gethostbyaddr_r( - const void* addr, socklen_t len, - int af, - struct hostent *host, - char *buffer, size_t buflen, - int *errnop, int *h_errnop) { - - return _nss_myhostname_gethostbyaddr2_r( - addr, len, - af, - host, - buffer, buflen, - errnop, h_errnop, - NULL); -} +NSS_GETHOSTBYNAME_FALLBACKS(myhostname); +NSS_GETHOSTBYADDR_FALLBACKS(myhostname);