From: Lennart Poettering Date: Thu, 10 Jul 2014 17:55:53 +0000 (+0200) Subject: nss-myhostname: various modernizations X-Git-Tag: v216~685 X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=commitdiff_plain;h=5502f0d97185218b93f01f9fe979a71bae38e213 nss-myhostname: various modernizations --- diff --git a/src/nss-myhostname/ifconf.h b/src/nss-myhostname/ifconf.h index cd598d2b4..92f03b261 100644 --- a/src/nss-myhostname/ifconf.h +++ b/src/nss-myhostname/ifconf.h @@ -26,43 +26,19 @@ #include #include +#include "socket-util.h" + struct address { unsigned char family; - uint8_t address[16]; + union in_addr_union address; unsigned char scope; int ifindex; }; -#define _public_ __attribute__ ((visibility("default"))) -#define _hidden_ __attribute__ ((visibility("hidden"))) - -int ifconf_acquire_addresses(struct address **_list, unsigned *_n_list) _hidden_; - static inline size_t PROTO_ADDRESS_SIZE(int proto) { assert(proto == AF_INET || proto == AF_INET6); return proto == AF_INET6 ? 16 : 4; } -static inline int address_compare(const void *_a, const void *_b) { - const struct address *a = _a, *b = _b; - - /* Order lowest scope first, IPv4 before IPv6, lowest interface index first */ - - if (a->scope < b->scope) - return -1; - if (a->scope > b->scope) - return 1; - - if (a->family == AF_INET && b->family == AF_INET6) - return -1; - if (a->family == AF_INET6 && b->family == AF_INET) - return 1; - - if (a->ifindex < b->ifindex) - return -1; - if (a->ifindex > b->ifindex) - return 1; - - return 0; -} +int ifconf_acquire_addresses(struct address **_list, unsigned *_n_list); diff --git a/src/nss-myhostname/netlink.c b/src/nss-myhostname/netlink.c index b4a464c06..e9518e321 100644 --- a/src/nss-myhostname/netlink.c +++ b/src/nss-myhostname/netlink.c @@ -23,16 +23,37 @@ #include "sd-rtnl.h" #include "rtnl-util.h" #include "macro.h" - #include "ifconf.h" +static int address_compare(const void *_a, const void *_b) { + const struct address *a = _a, *b = _b; + + /* Order lowest scope first, IPv4 before IPv6, lowest interface index first */ + + if (a->scope < b->scope) + return -1; + if (a->scope > b->scope) + return 1; + + if (a->family == AF_INET && b->family == AF_INET6) + return -1; + if (a->family == AF_INET6 && b->family == AF_INET) + return 1; + + if (a->ifindex < b->ifindex) + return -1; + if (a->ifindex > b->ifindex) + return 1; + + return 0; +} + int ifconf_acquire_addresses(struct address **_list, unsigned *_n_list) { - _cleanup_rtnl_unref_ sd_rtnl *rtnl = NULL; _cleanup_rtnl_message_unref_ sd_rtnl_message *req = NULL, *reply = NULL; - sd_rtnl_message *m; + _cleanup_rtnl_unref_ sd_rtnl *rtnl = NULL; _cleanup_free_ struct address *list = NULL; - struct address *new_list = NULL; - unsigned n_list = 0; + size_t n_list = 0, n_allocated = 0; + sd_rtnl_message *m; int r; r = sd_rtnl_open(&rtnl, 0); @@ -46,18 +67,11 @@ int ifconf_acquire_addresses(struct address **_list, unsigned *_n_list) { r = sd_rtnl_call(rtnl, req, 0, &reply); if (r < 0) return r; - m = reply; - do { - uint16_t type; - unsigned char scope; + for (m = reply; m; m = sd_rtnl_message_next(m)) { + struct address *a; unsigned char flags; - unsigned char family; - int ifindex; - union { - struct in_addr in; - struct in6_addr in6; - } address; + uint16_t type; r = sd_rtnl_message_get_errno(m); if (r < 0) @@ -70,72 +84,66 @@ int ifconf_acquire_addresses(struct address **_list, unsigned *_n_list) { if (type != RTM_NEWADDR) continue; - r = sd_rtnl_message_addr_get_scope(m, &scope); + r = sd_rtnl_message_addr_get_flags(m, &flags); if (r < 0) return r; - if (scope == RT_SCOPE_HOST || scope == RT_SCOPE_NOWHERE) + if (flags & IFA_F_DEPRECATED) continue; - r = sd_rtnl_message_addr_get_flags(m, &flags); + if (!GREEDY_REALLOC(list, n_allocated, n_list+1)) + return -ENOMEM; + + a = list + n_list; + + r = sd_rtnl_message_addr_get_scope(m, &a->scope); if (r < 0) return r; - if (flags & IFA_F_DEPRECATED) + if (a->scope == RT_SCOPE_HOST || a->scope == RT_SCOPE_NOWHERE) continue; - r = sd_rtnl_message_addr_get_family(m, &family); + r = sd_rtnl_message_addr_get_family(m, &a->family); if (r < 0) return r; - switch (family) { + switch (a->family) { + case AF_INET: - r = sd_rtnl_message_read_in_addr(m, IFA_LOCAL, &address.in); + r = sd_rtnl_message_read_in_addr(m, IFA_LOCAL, &a->address.in); if (r < 0) { - r = sd_rtnl_message_read_in_addr(m, IFA_ADDRESS, &address.in); + r = sd_rtnl_message_read_in_addr(m, IFA_ADDRESS, &a->address.in); if (r < 0) continue; } break; + case AF_INET6: - r = sd_rtnl_message_read_in6_addr(m, IFA_LOCAL, &address.in6); + r = sd_rtnl_message_read_in6_addr(m, IFA_LOCAL, &a->address.in6); if (r < 0) { - r = sd_rtnl_message_read_in6_addr(m, IFA_ADDRESS, &address.in6); + r = sd_rtnl_message_read_in6_addr(m, IFA_ADDRESS, &a->address.in6); if (r < 0) continue; } break; + default: continue; } - r = sd_rtnl_message_addr_get_ifindex(m, &ifindex); + r = sd_rtnl_message_addr_get_ifindex(m, &a->ifindex); if (r < 0) return r; - new_list = realloc(list, (n_list+1) * sizeof(struct address)); - if (!new_list) - return -ENOMEM; - else - list = new_list; - - assert_cc(sizeof(address) <= 16); - - list[n_list].family = family; - list[n_list].scope = scope; - memcpy(list[n_list].address, &address, sizeof(address)); - list[n_list].ifindex = ifindex; - n_list++; - - } while ((m = sd_rtnl_message_next(m))); + }; if (n_list) qsort(list, n_list, sizeof(struct address), address_compare); - *_n_list = n_list; *_list = list; list = NULL; + *_n_list = n_list; return 0; } diff --git a/src/nss-myhostname/nss-myhostname.c b/src/nss-myhostname/nss-myhostname.c index 60e256d54..9320e69eb 100644 --- a/src/nss-myhostname/nss-myhostname.c +++ b/src/nss-myhostname/nss-myhostname.c @@ -98,32 +98,39 @@ enum nss_status _nss_myhostname_gethostbyname4_r( int *errnop, int *h_errnop, int32_t *ttlp) { - unsigned lo_ifi; - char hn[HOST_NAME_MAX+1] = {}; - const char *canonical = NULL; - size_t l, idx, ms; - char *r_name; struct gaih_addrtuple *r_tuple, *r_tuple_prev = NULL; - struct address *addresses = NULL, *a; + _cleanup_free_ struct address *addresses = NULL; + _cleanup_free_ char *hn = NULL; + const char *canonical = NULL; unsigned n_addresses = 0, n; uint32_t local_address_ipv4; + struct address *a; + size_t l, idx, ms; + char *r_name; + int lo_ifi; - if (strcasecmp(name, "localhost") == 0) { + assert(name); + assert(pat); + assert(buffer); + assert(errnop); + assert(h_errnop); + + if (is_localhost(name)) { /* We respond to 'localhost', so that /etc/hosts * is optional */ canonical = "localhost"; local_address_ipv4 = htonl(INADDR_LOOPBACK); } else { - /* We respond to our local host name */ - - if (gethostname(hn, sizeof(hn)-1) < 0) { - *errnop = errno; + hn = gethostname_malloc(); + if (!hn) { + *errnop = ENOMEM; *h_errnop = NO_RECOVERY; - return NSS_STATUS_UNAVAIL; + return NSS_STATUS_TRYAGAIN; } - if (strcasecmp(name, hn) != 0) { + /* We respond to our local host name, our our hostname suffixed with a single dot. */ + if (!streq(name, hn) && !streq_ptr(startswith(name, hn), ".")) { *errnop = ENOENT; *h_errnop = HOST_NOT_FOUND; return NSS_STATUS_NOTFOUND; @@ -140,11 +147,10 @@ enum nss_status _nss_myhostname_gethostbyname4_r( lo_ifi = n_addresses <= 0 ? if_nametoindex(LOOPBACK_INTERFACE) : 0; l = strlen(canonical); - ms = ALIGN(l+1)+ALIGN(sizeof(struct gaih_addrtuple))*(n_addresses > 0 ? n_addresses : 2); + ms = ALIGN(l+1) + ALIGN(sizeof(struct gaih_addrtuple)) * (n_addresses > 0 ? n_addresses : 2); if (buflen < ms) { *errnop = ENOMEM; *h_errnop = NO_RECOVERY; - free(addresses); return NSS_STATUS_TRYAGAIN; } @@ -184,7 +190,7 @@ enum nss_status _nss_myhostname_gethostbyname4_r( r_tuple->name = r_name; r_tuple->family = a->family; r_tuple->scopeid = a->ifindex; - memcpy(r_tuple->addr, a->address, 16); + memcpy(r_tuple->addr, &a->address, 16); idx += ALIGN(sizeof(struct gaih_addrtuple)); r_tuple_prev = r_tuple; @@ -202,8 +208,6 @@ enum nss_status _nss_myhostname_gethostbyname4_r( if (ttlp) *ttlp = 0; - free(addresses); - return NSS_STATUS_SUCCESS; } @@ -224,6 +228,12 @@ static enum nss_status fill_in_hostent( struct address *a; unsigned n, c; + assert(canonical); + assert(result); + assert(buffer); + assert(errnop); + assert(h_errnop); + alen = PROTO_ADDRESS_SIZE(af); for (a = addresses, n = 0, c = 0; n < n_addresses; a++, n++) @@ -234,15 +244,14 @@ static enum nss_status fill_in_hostent( l_additional = additional ? strlen(additional) : 0; ms = ALIGN(l_canonical+1)+ (additional ? ALIGN(l_additional+1) : 0) + - sizeof(char*)+ + sizeof(char*) + (additional ? sizeof(char*) : 0) + - (c > 0 ? c : 1)*ALIGN(alen)+ - (c > 0 ? c+1 : 2)*sizeof(char*); + (c > 0 ? c : 1) * ALIGN(alen)+ + (c > 0 ? c+1 : 2) * sizeof(char*); if (buflen < ms) { *errnop = ENOMEM; *h_errnop = NO_RECOVERY; - free(addresses); return NSS_STATUS_TRYAGAIN; } @@ -277,7 +286,7 @@ static enum nss_status fill_in_hostent( if (af != a->family) continue; - memcpy(r_addr + i*ALIGN(alen), a->address, alen); + memcpy(r_addr + i*ALIGN(alen), &a->address, alen); i++; } @@ -330,8 +339,6 @@ static enum nss_status fill_in_hostent( if (canonp) *canonp = r_name; - free(addresses); - return NSS_STATUS_SUCCESS; } @@ -344,11 +351,17 @@ enum nss_status _nss_myhostname_gethostbyname3_r( int32_t *ttlp, char **canonp) { - char hn[HOST_NAME_MAX+1] = {}; - struct address *addresses = NULL; - unsigned n_addresses = 0; + _cleanup_free_ struct address *addresses = NULL; const char *canonical, *additional = NULL; + _cleanup_free_ char *hn = NULL; uint32_t local_address_ipv4; + unsigned n_addresses = 0; + + assert(name); + assert(host); + assert(buffer); + assert(errnop); + assert(h_errnop); if (af == AF_UNSPEC) af = AF_INET; @@ -359,17 +372,18 @@ enum nss_status _nss_myhostname_gethostbyname3_r( return NSS_STATUS_UNAVAIL; } - if (strcasecmp(name, "localhost") == 0) { + if (is_localhost(name)) { canonical = "localhost"; local_address_ipv4 = htonl(INADDR_LOOPBACK); } else { - if (gethostname(hn, sizeof(hn)-1) < 0) { - *errnop = errno; + hn = gethostname_malloc(); + if (!hn) { + *errnop = ENOMEM; *h_errnop = NO_RECOVERY; - return NSS_STATUS_UNAVAIL; + return NSS_STATUS_TRYAGAIN; } - if (strcasecmp(name, hn) != 0) { + if (!streq(name, hn) && !streq_ptr(startswith(name, hn), ".")) { *errnop = ENOENT; *h_errnop = HOST_NOT_FOUND; return NSS_STATUS_NOTFOUND; @@ -435,12 +449,18 @@ enum nss_status _nss_myhostname_gethostbyaddr2_r( int *errnop, int *h_errnop, int32_t *ttlp) { - char hn[HOST_NAME_MAX+1] = {}; - struct address *addresses = NULL; - struct address *a; - unsigned n_addresses = 0, n; - uint32_t local_address_ipv4 = LOCALADDRESS_IPV4; const char *canonical = NULL, *additional = NULL; + uint32_t local_address_ipv4 = LOCALADDRESS_IPV4; + _cleanup_free_ struct address *addresses = NULL; + _cleanup_free_ char *hn = NULL; + unsigned n_addresses = 0, n; + struct address *a; + + assert(addr); + assert(host); + assert(buffer); + assert(errnop); + assert(h_errnop); if (len != PROTO_ADDRESS_SIZE(af)) { *errnop = EINVAL; @@ -478,26 +498,22 @@ enum nss_status _nss_myhostname_gethostbyaddr2_r( if (af != a->family) continue; - if (memcmp(addr, a->address, PROTO_ADDRESS_SIZE(af)) == 0) + if (memcmp(addr, &a->address, PROTO_ADDRESS_SIZE(af)) == 0) goto found; } *errnop = ENOENT; *h_errnop = HOST_NOT_FOUND; - free(addresses); - return NSS_STATUS_NOTFOUND; found: if (!canonical) { - if (gethostname(hn, sizeof(hn)-1) < 0) { - *errnop = errno; + hn = gethostname_malloc(); + if (!hn) { + *errnop = ENOMEM; *h_errnop = NO_RECOVERY; - - free(addresses); - - return NSS_STATUS_UNAVAIL; + return NSS_STATUS_TRYAGAIN; } canonical = hn;