static void sync_with_progress(void) {
unsigned long long dirty = ULONG_LONG_MAX;
unsigned checks;
pid_t pid;
int r;
BLOCK_SIGNALS(SIGCHLD);
/* Due to the possiblity of the sync operation hanging, we fork a child process and monitor the progress. If
* the timeout lapses, the assumption is that that particular sync stalled. */
r = asynchronous_sync(&pid);
if (r < 0) {
log_error_errno(r, "Failed to fork sync(): %m");
return;
}
log_info("Syncing filesystems and block devices.");
/* Start monitoring the sync operation. If more than
* SYNC_PROGRESS_ATTEMPTS lapse without progress being made,
* we assume that the sync is stalled */
for (checks = 0; checks < SYNC_PROGRESS_ATTEMPTS; checks++) {
r = wait_for_terminate_with_timeout(pid, SYNC_TIMEOUT_USEC);
if (r == 0)
/* Sync finished without error.
* (The sync itself does not return an error code) */
return;
else if (r == -ETIMEDOUT) {
/* Reset the check counter if the "Dirty" value is
* decreasing */
if (sync_making_progress(&dirty))
checks = 0;
} else {
log_error_errno(r, "Failed to sync filesystems and block devices: %m");
return;
}
}
/* Only reached in the event of a timeout. We should issue a kill
* to the stray process. */
log_error("Syncing filesystems and block devices - timed out, issuing SIGKILL to PID "PID_FMT".", pid);
(void) kill(pid, SIGKILL);
}
static void test_safe_fork(void) {
siginfo_t status;
pid_t pid;
int r;
BLOCK_SIGNALS(SIGCHLD);
r = safe_fork("(test-child)", FORK_RESET_SIGNALS|FORK_CLOSE_ALL_FDS|FORK_DEATHSIG|FORK_NULL_STDIO|FORK_REOPEN_LOG, &pid);
assert_se(r >= 0);
if (r == 0) {
/* child */
usleep(100 * USEC_PER_MSEC);
_exit(88);
}
assert_se(wait_for_terminate(pid, &status) >= 0);
assert_se(status.si_code == CLD_EXITED);
assert_se(status.si_status == 88);
}
enum nss_status _nss_resolve_gethostbyname4_r(
const char *name,
struct gaih_addrtuple **pat,
char *buffer, size_t buflen,
int *errnop, int *h_errnop,
int32_t *ttlp) {
_cleanup_(sd_bus_message_unrefp) sd_bus_message *req = NULL, *reply = NULL;
_cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
struct gaih_addrtuple *r_tuple, *r_tuple_first = NULL;
_cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
enum nss_status ret = NSS_STATUS_UNAVAIL;
const char *canonical = NULL;
size_t l, ms, idx;
char *r_name;
int c, r, i = 0;
BLOCK_SIGNALS(NSS_SIGNALS_BLOCK);
assert(name);
assert(pat);
assert(buffer);
assert(errnop);
assert(h_errnop);
r = sd_bus_open_system(&bus);
if (r < 0)
goto fail;
r = sd_bus_message_new_method_call(
bus,
&req,
"org.freedesktop.resolve1",
"/org/freedesktop/resolve1",
"org.freedesktop.resolve1.Manager",
"ResolveHostname");
if (r < 0)
goto fail;
r = sd_bus_message_set_auto_start(req, false);
if (r < 0)
goto fail;
r = sd_bus_message_append(req, "isit", 0, name, AF_UNSPEC, (uint64_t) 0);
if (r < 0)
goto fail;
r = sd_bus_call(bus, req, SD_RESOLVED_QUERY_TIMEOUT_USEC, &error, &reply);
if (r < 0) {
if (sd_bus_error_has_name(&error, _BUS_ERROR_DNS "NXDOMAIN")) {
*errnop = ESRCH;
*h_errnop = HOST_NOT_FOUND;
return NSS_STATUS_NOTFOUND;
}
/* Return NSS_STATUS_UNAVAIL when communication with systemd-resolved fails,
allowing falling back to other nss modules. Treat all other error conditions as
NOTFOUND. This includes DNSSEC errors and suchlike. (We don't use UNAVAIL in this
case so that the nsswitch.conf configuration can distuingish such executed but
negative replies from complete failure to talk to resolved). */
if (!bus_error_shall_fallback(&error))
ret = NSS_STATUS_NOTFOUND;
goto fail;
}
c = count_addresses(reply, AF_UNSPEC, &canonical);
if (c < 0) {
r = c;
goto fail;
}
if (c == 0) {
*errnop = ESRCH;
*h_errnop = HOST_NOT_FOUND;
return NSS_STATUS_NOTFOUND;
}
if (isempty(canonical))
canonical = name;
l = strlen(canonical);
ms = ALIGN(l+1) + ALIGN(sizeof(struct gaih_addrtuple)) * c;
if (buflen < ms) {
*errnop = ERANGE;
*h_errnop = NETDB_INTERNAL;
return NSS_STATUS_TRYAGAIN;
}
/* First, append name */
r_name = buffer;
memcpy(r_name, canonical, l+1);
idx = ALIGN(l+1);
/* Second, append addresses */
r_tuple_first = (struct gaih_addrtuple*) (buffer + idx);
r = sd_bus_message_enter_container(reply, 'a', "(iiay)");
if (r < 0)
goto fail;
while ((r = sd_bus_message_enter_container(reply, 'r', "iiay")) > 0) {
int family, ifindex;
const void *a;
size_t sz;
assert_cc(sizeof(int32_t) == sizeof(int));
r = sd_bus_message_read(reply, "ii", &ifindex, &family);
if (r < 0)
goto fail;
if (ifindex < 0) {
r = -EINVAL;
goto fail;
}
r = sd_bus_message_read_array(reply, 'y', &a, &sz);
if (r < 0)
goto fail;
r = sd_bus_message_exit_container(reply);
if (r < 0)
goto fail;
if (!IN_SET(family, AF_INET, AF_INET6))
continue;
if (sz != FAMILY_ADDRESS_SIZE(family)) {
r = -EINVAL;
goto fail;
}
r_tuple = (struct gaih_addrtuple*) (buffer + idx);
r_tuple->next = i == c-1 ? NULL : (struct gaih_addrtuple*) ((char*) r_tuple + ALIGN(sizeof(struct gaih_addrtuple)));
r_tuple->name = r_name;
r_tuple->family = family;
r_tuple->scopeid = ifindex_to_scopeid(family, a, ifindex);
memcpy(r_tuple->addr, a, sz);
idx += ALIGN(sizeof(struct gaih_addrtuple));
i++;
}
if (r < 0)
goto fail;
assert(i == c);
assert(idx == ms);
if (*pat)
**pat = *r_tuple_first;
else
*pat = r_tuple_first;
if (ttlp)
*ttlp = 0;
/* Explicitly reset all error variables */
*errnop = 0;
*h_errnop = NETDB_SUCCESS;
h_errno = 0;
return NSS_STATUS_SUCCESS;
fail:
*errnop = -r;
*h_errnop = NO_RECOVERY;
return ret;
}
enum nss_status _nss_resolve_gethostbyaddr2_r(
const void* addr, socklen_t len,
int af,
struct hostent *result,
char *buffer, size_t buflen,
int *errnop, int *h_errnop,
int32_t *ttlp) {
_cleanup_(sd_bus_message_unrefp) sd_bus_message *req = NULL, *reply = NULL;
_cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
char *r_name, *r_aliases, *r_addr, *r_addr_list;
_cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
enum nss_status ret = NSS_STATUS_UNAVAIL;
unsigned c = 0, i = 0;
size_t ms = 0, idx;
const char *n;
int r, ifindex;
BLOCK_SIGNALS(NSS_SIGNALS_BLOCK);
assert(addr);
assert(result);
assert(buffer);
assert(errnop);
assert(h_errnop);
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;
}
r = sd_bus_open_system(&bus);
if (r < 0)
goto fail;
r = sd_bus_message_new_method_call(
bus,
&req,
"org.freedesktop.resolve1",
"/org/freedesktop/resolve1",
"org.freedesktop.resolve1.Manager",
"ResolveAddress");
if (r < 0)
goto fail;
r = sd_bus_message_set_auto_start(req, false);
if (r < 0)
goto fail;
r = sd_bus_message_append(req, "ii", 0, af);
if (r < 0)
goto fail;
r = sd_bus_message_append_array(req, 'y', addr, len);
if (r < 0)
goto fail;
r = sd_bus_message_append(req, "t", (uint64_t) 0);
if (r < 0)
goto fail;
r = sd_bus_call(bus, req, SD_RESOLVED_QUERY_TIMEOUT_USEC, &error, &reply);
if (r < 0) {
if (sd_bus_error_has_name(&error, _BUS_ERROR_DNS "NXDOMAIN")) {
*errnop = ESRCH;
*h_errnop = HOST_NOT_FOUND;
return NSS_STATUS_NOTFOUND;
}
if (!bus_error_shall_fallback(&error))
ret = NSS_STATUS_NOTFOUND;
goto fail;
}
r = sd_bus_message_enter_container(reply, 'a', "(is)");
if (r < 0)
goto fail;
while ((r = sd_bus_message_read(reply, "(is)", &ifindex, &n)) > 0) {
if (ifindex < 0) {
r = -EINVAL;
goto fail;
}
c++;
ms += ALIGN(strlen(n) + 1);
}
if (r < 0)
goto fail;
r = sd_bus_message_rewind(reply, false);
if (r < 0)
return r;
if (c <= 0) {
*errnop = ESRCH;
*h_errnop = HOST_NOT_FOUND;
return NSS_STATUS_NOTFOUND;
}
ms += ALIGN(len) + /* the address */
2 * sizeof(char*) + /* pointers to the address, plus trailing NULL */
c * sizeof(char*); /* pointers to aliases, plus trailing NULL */
if (buflen < ms) {
*errnop = ERANGE;
*h_errnop = NETDB_INTERNAL;
return NSS_STATUS_TRYAGAIN;
}
/* First, place address */
r_addr = buffer;
memcpy(r_addr, addr, len);
idx = ALIGN(len);
/* Second, place address list */
r_addr_list = buffer + idx;
((char**) r_addr_list)[0] = r_addr;
((char**) r_addr_list)[1] = NULL;
idx += sizeof(char*) * 2;
/* Third, reserve space for the aliases array */
r_aliases = buffer + idx;
idx += sizeof(char*) * c;
/* Fourth, place aliases */
i = 0;
r_name = buffer + idx;
while ((r = sd_bus_message_read(reply, "(is)", &ifindex, &n)) > 0) {
char *p;
size_t l;
l = strlen(n);
p = buffer + idx;
memcpy(p, n, l+1);
if (i > 0)
((char**) r_aliases)[i-1] = p;
i++;
idx += ALIGN(l+1);
}
if (r < 0)
goto fail;
((char**) r_aliases)[c-1] = NULL;
assert(idx == ms);
result->h_name = r_name;
result->h_aliases = (char**) r_aliases;
result->h_addrtype = af;
result->h_length = len;
result->h_addr_list = (char**) r_addr_list;
if (ttlp)
*ttlp = 0;
/* Explicitly reset all error variables */
*errnop = 0;
*h_errnop = NETDB_SUCCESS;
h_errno = 0;
return NSS_STATUS_SUCCESS;
fail:
*errnop = -r;
*h_errnop = NO_RECOVERY;
return ret;
}
enum nss_status _nss_resolve_gethostbyname3_r(
const char *name,
int af,
struct hostent *result,
char *buffer, size_t buflen,
int *errnop, int *h_errnop,
int32_t *ttlp,
char **canonp) {
_cleanup_(sd_bus_message_unrefp) sd_bus_message *req = NULL, *reply = NULL;
_cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
char *r_name, *r_aliases, *r_addr, *r_addr_list;
_cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
enum nss_status ret = NSS_STATUS_UNAVAIL;
size_t l, idx, ms, alen;
const char *canonical;
int c, r, i = 0;
BLOCK_SIGNALS(NSS_SIGNALS_BLOCK);
assert(name);
assert(result);
assert(buffer);
assert(errnop);
assert(h_errnop);
if (af == AF_UNSPEC)
af = AF_INET;
if (!IN_SET(af, AF_INET, AF_INET6)) {
r = -EAFNOSUPPORT;
goto fail;
}
r = sd_bus_open_system(&bus);
if (r < 0)
goto fail;
r = sd_bus_message_new_method_call(
bus,
&req,
"org.freedesktop.resolve1",
"/org/freedesktop/resolve1",
"org.freedesktop.resolve1.Manager",
"ResolveHostname");
if (r < 0)
goto fail;
r = sd_bus_message_set_auto_start(req, false);
if (r < 0)
goto fail;
r = sd_bus_message_append(req, "isit", 0, name, af, (uint64_t) 0);
if (r < 0)
goto fail;
r = sd_bus_call(bus, req, SD_RESOLVED_QUERY_TIMEOUT_USEC, &error, &reply);
if (r < 0) {
if (sd_bus_error_has_name(&error, _BUS_ERROR_DNS "NXDOMAIN")) {
*errnop = ESRCH;
*h_errnop = HOST_NOT_FOUND;
return NSS_STATUS_NOTFOUND;
}
if (!bus_error_shall_fallback(&error))
ret = NSS_STATUS_NOTFOUND;
goto fail;
}
c = count_addresses(reply, af, &canonical);
if (c < 0) {
r = c;
goto fail;
}
if (c == 0) {
*errnop = ESRCH;
*h_errnop = HOST_NOT_FOUND;
return NSS_STATUS_NOTFOUND;
}
if (isempty(canonical))
canonical = name;
alen = FAMILY_ADDRESS_SIZE(af);
l = strlen(canonical);
ms = ALIGN(l+1) + c * ALIGN(alen) + (c+2) * sizeof(char*);
if (buflen < ms) {
*errnop = ERANGE;
*h_errnop = NETDB_INTERNAL;
return NSS_STATUS_TRYAGAIN;
}
/* First, append name */
r_name = buffer;
memcpy(r_name, canonical, l+1);
idx = ALIGN(l+1);
/* Second, create empty aliases array */
r_aliases = buffer + idx;
((char**) r_aliases)[0] = NULL;
idx += sizeof(char*);
/* Third, append addresses */
r_addr = buffer + idx;
r = sd_bus_message_enter_container(reply, 'a', "(iiay)");
if (r < 0)
goto fail;
while ((r = sd_bus_message_enter_container(reply, 'r', "iiay")) > 0) {
int ifindex, family;
const void *a;
size_t sz;
r = sd_bus_message_read(reply, "ii", &ifindex, &family);
if (r < 0)
goto fail;
if (ifindex < 0) {
r = -EINVAL;
goto fail;
}
r = sd_bus_message_read_array(reply, 'y', &a, &sz);
if (r < 0)
goto fail;
r = sd_bus_message_exit_container(reply);
if (r < 0)
goto fail;
if (family != af)
continue;
if (sz != alen) {
r = -EINVAL;
goto fail;
}
memcpy(r_addr + i*ALIGN(alen), a, alen);
i++;
}
if (r < 0)
goto fail;
assert(i == c);
idx += c * ALIGN(alen);
/* Fourth, append address pointer array */
r_addr_list = buffer + idx;
for (i = 0; i < c; i++)
((char**) r_addr_list)[i] = r_addr + i*ALIGN(alen);
((char**) r_addr_list)[i] = NULL;
idx += (c+1) * sizeof(char*);
assert(idx == ms);
result->h_name = r_name;
result->h_aliases = (char**) r_aliases;
result->h_addrtype = af;
result->h_length = alen;
result->h_addr_list = (char**) r_addr_list;
/* Explicitly reset all error variables */
*errnop = 0;
*h_errnop = NETDB_SUCCESS;
h_errno = 0;
if (ttlp)
*ttlp = 0;
if (canonp)
*canonp = r_name;
return NSS_STATUS_SUCCESS;
fail:
*errnop = -r;
*h_errnop = NO_RECOVERY;
return ret;
}
enum nss_status _nss_systemd_getpwnam_r(
const char *name,
struct passwd *pwd,
char *buffer, size_t buflen,
int *errnop) {
_cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
_cleanup_(sd_bus_message_unrefp) sd_bus_message* reply = NULL;
_cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
uint32_t translated;
size_t l;
int r;
BLOCK_SIGNALS(NSS_SIGNALS_BLOCK);
assert(name);
assert(pwd);
/* Make sure that we don't go in circles when allocating a dynamic UID by checking our own database */
if (getenv_bool("SYSTEMD_NSS_DYNAMIC_BYPASS") > 0)
goto not_found;
r = sd_bus_open_system(&bus);
if (r < 0)
goto fail;
r = sd_bus_call_method(bus,
"org.freedesktop.systemd1",
"/org/freedesktop/systemd1",
"org.freedesktop.systemd1.Manager",
"LookupDynamicUserByName",
&error,
&reply,
"s",
name);
if (r < 0) {
if (sd_bus_error_has_name(&error, BUS_ERROR_NO_SUCH_DYNAMIC_USER))
goto not_found;
goto fail;
}
r = sd_bus_message_read(reply, "u", &translated);
if (r < 0)
goto fail;
l = strlen(name);
if (buflen < l+1) {
*errnop = ENOMEM;
return NSS_STATUS_TRYAGAIN;
}
memcpy(buffer, name, l+1);
pwd->pw_name = buffer;
pwd->pw_uid = (uid_t) translated;
pwd->pw_gid = (uid_t) translated;
pwd->pw_gecos = (char*) "Dynamic User";
pwd->pw_passwd = (char*) "*"; /* locked */
pwd->pw_dir = (char*) "/";
pwd->pw_shell = (char*) "/sbin/nologin";
*errnop = 0;
return NSS_STATUS_SUCCESS;
not_found:
*errnop = 0;
return NSS_STATUS_NOTFOUND;
fail:
*errnop = -r;
return NSS_STATUS_UNAVAIL;
}
enum nss_status _nss_systemd_getgrgid_r(
gid_t gid,
struct group *gr,
char *buffer, size_t buflen,
int *errnop) {
_cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
_cleanup_(sd_bus_message_unrefp) sd_bus_message* reply = NULL;
_cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
const char *translated;
size_t l;
int r;
BLOCK_SIGNALS(NSS_SIGNALS_BLOCK);
if (!gid_is_valid(gid)) {
r = -EINVAL;
goto fail;
}
if (gid <= SYSTEM_GID_MAX)
goto not_found;
if (getenv_bool("SYSTEMD_NSS_DYNAMIC_BYPASS") > 0)
goto not_found;
r = sd_bus_open_system(&bus);
if (r < 0)
goto fail;
r = sd_bus_call_method(bus,
"org.freedesktop.systemd1",
"/org/freedesktop/systemd1",
"org.freedesktop.systemd1.Manager",
"LookupDynamicUserByUID",
&error,
&reply,
"u",
(uint32_t) gid);
if (r < 0) {
if (sd_bus_error_has_name(&error, BUS_ERROR_NO_SUCH_DYNAMIC_USER))
goto not_found;
goto fail;
}
r = sd_bus_message_read(reply, "s", &translated);
if (r < 0)
goto fail;
l = sizeof(char*) + strlen(translated) + 1;
if (buflen < l) {
*errnop = ENOMEM;
return NSS_STATUS_TRYAGAIN;
}
memzero(buffer, sizeof(char*));
strcpy(buffer + sizeof(char*), translated);
gr->gr_name = buffer + sizeof(char*);
gr->gr_gid = gid;
gr->gr_passwd = (char*) "*"; /* locked */
gr->gr_mem = (char**) buffer;
*errnop = 0;
return NSS_STATUS_SUCCESS;
not_found:
*errnop = 0;
return NSS_STATUS_NOTFOUND;
fail:
*errnop = -r;
return NSS_STATUS_UNAVAIL;
}
enum nss_status _nss_systemd_getpwuid_r(
uid_t uid,
struct passwd *pwd,
char *buffer, size_t buflen,
int *errnop) {
_cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
_cleanup_(sd_bus_message_unrefp) sd_bus_message* reply = NULL;
_cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
const char *translated;
size_t l;
int r;
BLOCK_SIGNALS(NSS_SIGNALS_BLOCK);
if (!uid_is_valid(uid)) {
r = -EINVAL;
goto fail;
}
if (uid <= SYSTEM_UID_MAX)
goto not_found;
if (getenv_bool("SYSTEMD_NSS_DYNAMIC_BYPASS") > 0)
goto not_found;
r = sd_bus_open_system(&bus);
if (r < 0)
goto fail;
r = sd_bus_call_method(bus,
"org.freedesktop.systemd1",
"/org/freedesktop/systemd1",
"org.freedesktop.systemd1.Manager",
"LookupDynamicUserByUID",
&error,
&reply,
"u",
(uint32_t) uid);
if (r < 0) {
if (sd_bus_error_has_name(&error, BUS_ERROR_NO_SUCH_DYNAMIC_USER))
goto not_found;
goto fail;
}
r = sd_bus_message_read(reply, "s", &translated);
if (r < 0)
goto fail;
l = strlen(translated) + 1;
if (buflen < l) {
*errnop = ENOMEM;
return NSS_STATUS_TRYAGAIN;
}
memcpy(buffer, translated, l);
pwd->pw_name = buffer;
pwd->pw_uid = uid;
pwd->pw_gid = uid;
pwd->pw_gecos = (char*) "Dynamic User";
pwd->pw_passwd = (char*) "*"; /* locked */
pwd->pw_dir = (char*) "/";
pwd->pw_shell = (char*) "/sbin/nologin";
*errnop = 0;
return NSS_STATUS_SUCCESS;
not_found:
*errnop = 0;
return NSS_STATUS_NOTFOUND;
fail:
*errnop = -r;
return NSS_STATUS_UNAVAIL;
}
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) {
const char *canonical = NULL, *additional = NULL;
uint32_t local_address_ipv4 = LOCALADDRESS_IPV4;
_cleanup_free_ struct local_address *addresses = NULL;
_cleanup_free_ char *hn = NULL;
int n_addresses = 0;
struct local_address *a;
bool additional_from_hostname = false;
unsigned n;
PROTECT_ERRNO;
BLOCK_SIGNALS(NSS_SIGNALS_BLOCK);
assert(addr);
assert(host);
assert(buffer);
assert(errnop);
assert(h_errnop);
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;
if ((*(uint32_t*) addr) == htobe32(INADDR_LOOPBACK)) {
canonical = "localhost";
local_address_ipv4 = htobe32(INADDR_LOOPBACK);
goto found;
}
} else {
assert(af == AF_INET6);
if (memcmp(addr, LOCALADDRESS_IPV6, 16) == 0) {
canonical = "localhost";
additional_from_hostname = true;
goto found;
}
}
n_addresses = local_addresses(NULL, 0, AF_UNSPEC, &addresses);
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;
}
addresses = mfree(addresses);
n_addresses = local_gateways(NULL, 0, AF_UNSPEC, &addresses);
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) {
canonical = "_gateway";
goto found;
}
}
*h_errnop = HOST_NOT_FOUND;
return NSS_STATUS_NOTFOUND;
found:
if (!canonical || additional_from_hostname) {
hn = gethostname_malloc();
if (!hn) {
*errnop = ENOMEM;
*h_errnop = NO_RECOVERY;
return NSS_STATUS_TRYAGAIN;
}
if (!canonical)
canonical = hn;
else
additional = hn;
}
return fill_in_hostent(
canonical, additional,
af,
addresses, n_addresses,
local_address_ipv4,
host,
buffer, buflen,
errnop, h_errnop,
ttlp,
NULL);
}
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) {
_cleanup_free_ struct local_address *addresses = NULL;
const char *canonical, *additional = NULL;
_cleanup_free_ char *hn = NULL;
uint32_t local_address_ipv4 = 0;
int n_addresses = 0;
PROTECT_ERRNO;
BLOCK_SIGNALS(NSS_SIGNALS_BLOCK);
assert(name);
assert(host);
assert(buffer);
assert(errnop);
assert(h_errnop);
if (af == AF_UNSPEC)
af = AF_INET;
if (!IN_SET(af, AF_INET, AF_INET6)) {
*errnop = EAFNOSUPPORT;
*h_errnop = NO_DATA;
return NSS_STATUS_UNAVAIL;
}
if (is_localhost(name)) {
canonical = "localhost";
local_address_ipv4 = htobe32(INADDR_LOOPBACK);
} else if (is_gateway_hostname(name)) {
n_addresses = local_gateways(NULL, 0, af, &addresses);
if (n_addresses <= 0) {
*h_errnop = HOST_NOT_FOUND;
return NSS_STATUS_NOTFOUND;
}
canonical = "_gateway";
} else {
hn = gethostname_malloc();
if (!hn) {
*errnop = ENOMEM;
*h_errnop = NO_RECOVERY;
return NSS_STATUS_TRYAGAIN;
}
if (!streq(name, hn) && !streq_ptr(startswith(name, hn), ".")) {
*h_errnop = HOST_NOT_FOUND;
return NSS_STATUS_NOTFOUND;
}
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;
local_address_ipv4 = LOCALADDRESS_IPV4;
}
return fill_in_hostent(
canonical, additional,
af,
addresses, n_addresses,
local_address_ipv4,
host,
buffer, buflen,
errnop, h_errnop,
ttlp,
canonp);
}
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) {
struct gaih_addrtuple *r_tuple, *r_tuple_prev = NULL;
_cleanup_free_ struct local_address *addresses = NULL;
_cleanup_free_ char *hn = NULL;
const char *canonical = NULL;
int n_addresses = 0;
uint32_t local_address_ipv4;
struct local_address *a;
size_t l, idx, ms;
char *r_name;
unsigned n;
PROTECT_ERRNO;
BLOCK_SIGNALS(NSS_SIGNALS_BLOCK);
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 = htobe32(INADDR_LOOPBACK);
} else if (is_gateway_hostname(name)) {
n_addresses = local_gateways(NULL, 0, AF_UNSPEC, &addresses);
if (n_addresses <= 0) {
*h_errnop = HOST_NOT_FOUND;
return NSS_STATUS_NOTFOUND;
}
canonical = "_gateway";
} else {
hn = gethostname_malloc();
if (!hn) {
*errnop = ENOMEM;
*h_errnop = NO_RECOVERY;
return NSS_STATUS_TRYAGAIN;
}
/* We respond to our local host name, our hostname suffixed with a single dot. */
if (!streq(name, hn) && !streq_ptr(startswith(name, hn), ".")) {
*h_errnop = HOST_NOT_FOUND;
return NSS_STATUS_NOTFOUND;
}
n_addresses = local_addresses(NULL, 0, AF_UNSPEC, &addresses);
if (n_addresses < 0)
n_addresses = 0;
canonical = hn;
local_address_ipv4 = LOCALADDRESS_IPV4;
}
l = strlen(canonical);
ms = ALIGN(l+1) + ALIGN(sizeof(struct gaih_addrtuple)) * (n_addresses > 0 ? n_addresses : 2);
if (buflen < ms) {
*errnop = ERANGE;
*h_errnop = NETDB_INTERNAL;
return NSS_STATUS_TRYAGAIN;
}
/* First, fill in hostname */
r_name = buffer;
memcpy(r_name, canonical, l+1);
idx = ALIGN(l+1);
assert(n_addresses >= 0);
if (n_addresses == 0) {
/* Second, fill in IPv6 tuple */
r_tuple = (struct gaih_addrtuple*) (buffer + idx);
r_tuple->next = r_tuple_prev;
r_tuple->name = r_name;
r_tuple->family = AF_INET6;
memcpy(r_tuple->addr, LOCALADDRESS_IPV6, 16);
r_tuple->scopeid = 0;
idx += ALIGN(sizeof(struct gaih_addrtuple));
r_tuple_prev = r_tuple;
/* Third, fill in IPv4 tuple */
r_tuple = (struct gaih_addrtuple*) (buffer + idx);
r_tuple->next = r_tuple_prev;
r_tuple->name = r_name;
r_tuple->family = AF_INET;
*(uint32_t*) r_tuple->addr = local_address_ipv4;
r_tuple->scopeid = 0;
idx += ALIGN(sizeof(struct gaih_addrtuple));
r_tuple_prev = r_tuple;
}
/* Fourth, fill actual addresses in, but in backwards order */
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;
r_tuple->family = a->family;
r_tuple->scopeid = a->family == AF_INET6 && IN6_IS_ADDR_LINKLOCAL(&a->address.in6) ? a->ifindex : 0;
memcpy(r_tuple->addr, &a->address, 16);
idx += ALIGN(sizeof(struct gaih_addrtuple));
r_tuple_prev = r_tuple;
}
/* Verify the size matches */
assert(idx == ms);
/* Nscd expects us to store the first record in **pat. */
if (*pat)
**pat = *r_tuple_prev;
else
*pat = r_tuple_prev;
if (ttlp)
*ttlp = 0;
/* Explicitly reset both *h_errnop and h_errno to work around
* https://bugzilla.redhat.com/show_bug.cgi?id=1125975 */
*h_errnop = NETDB_SUCCESS;
h_errno = 0;
return NSS_STATUS_SUCCESS;
}
enum nss_status _nss_resolve_gethostbyname4_r(
const char *name,
struct gaih_addrtuple **pat,
char *buffer, size_t buflen,
int *errnop, int *h_errnop,
int32_t *ttlp) {
_cleanup_(sd_bus_message_unrefp) sd_bus_message *req = NULL, *reply = NULL;
_cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
struct gaih_addrtuple *r_tuple, *r_tuple_first = NULL;
_cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
const char *canonical = NULL;
size_t l, ms, idx;
char *r_name;
int c, r, i = 0;
BLOCK_SIGNALS(NSS_SIGNALS_BLOCK);
assert(name);
assert(pat);
assert(buffer);
assert(errnop);
assert(h_errnop);
r = sd_bus_open_system(&bus);
if (r < 0)
goto fallback;
r = sd_bus_message_new_method_call(
bus,
&req,
"org.freedesktop.resolve1",
"/org/freedesktop/resolve1",
"org.freedesktop.resolve1.Manager",
"ResolveHostname");
if (r < 0)
goto fail;
r = sd_bus_message_set_auto_start(req, false);
if (r < 0)
goto fail;
r = sd_bus_message_append(req, "isit", 0, name, AF_UNSPEC, (uint64_t) 0);
if (r < 0)
goto fail;
r = sd_bus_call(bus, req, DNS_CALL_TIMEOUT_USEC, &error, &reply);
if (r < 0) {
if (sd_bus_error_has_name(&error, _BUS_ERROR_DNS "NXDOMAIN")) {
*errnop = ESRCH;
*h_errnop = HOST_NOT_FOUND;
return NSS_STATUS_NOTFOUND;
}
if (bus_error_shall_fallback(&error))
goto fallback;
goto fail;
}
c = count_addresses(reply, AF_UNSPEC, &canonical);
if (c < 0) {
r = c;
goto fail;
}
if (c == 0) {
*errnop = ESRCH;
*h_errnop = HOST_NOT_FOUND;
return NSS_STATUS_NOTFOUND;
}
if (isempty(canonical))
canonical = name;
l = strlen(canonical);
ms = ALIGN(l+1) + ALIGN(sizeof(struct gaih_addrtuple)) * c;
if (buflen < ms) {
*errnop = ENOMEM;
*h_errnop = TRY_AGAIN;
return NSS_STATUS_TRYAGAIN;
}
/* First, append name */
r_name = buffer;
memcpy(r_name, canonical, l+1);
idx = ALIGN(l+1);
/* Second, append addresses */
r_tuple_first = (struct gaih_addrtuple*) (buffer + idx);
r = sd_bus_message_enter_container(reply, 'a', "(iiay)");
if (r < 0)
goto fail;
while ((r = sd_bus_message_enter_container(reply, 'r', "iiay")) > 0) {
int family, ifindex;
const void *a;
size_t sz;
assert_cc(sizeof(int32_t) == sizeof(int));
r = sd_bus_message_read(reply, "ii", &ifindex, &family);
if (r < 0)
goto fail;
if (ifindex < 0) {
r = -EINVAL;
goto fail;
}
r = sd_bus_message_read_array(reply, 'y', &a, &sz);
if (r < 0)
goto fail;
r = sd_bus_message_exit_container(reply);
if (r < 0)
goto fail;
if (!IN_SET(family, AF_INET, AF_INET6))
continue;
if (sz != FAMILY_ADDRESS_SIZE(family)) {
r = -EINVAL;
goto fail;
}
r_tuple = (struct gaih_addrtuple*) (buffer + idx);
r_tuple->next = i == c-1 ? NULL : (struct gaih_addrtuple*) ((char*) r_tuple + ALIGN(sizeof(struct gaih_addrtuple)));
r_tuple->name = r_name;
r_tuple->family = family;
r_tuple->scopeid = ifindex;
memcpy(r_tuple->addr, a, sz);
idx += ALIGN(sizeof(struct gaih_addrtuple));
i++;
}
if (r < 0)
goto fail;
assert(i == c);
assert(idx == ms);
if (*pat)
**pat = *r_tuple_first;
else
*pat = r_tuple_first;
if (ttlp)
*ttlp = 0;
/* Explicitly reset all error variables */
*errnop = 0;
*h_errnop = NETDB_SUCCESS;
h_errno = 0;
return NSS_STATUS_SUCCESS;
fallback:
{
_nss_gethostbyname4_r_t fallback;
fallback = (_nss_gethostbyname4_r_t)
find_fallback("libnss_dns.so.2", "_nss_dns_gethostbyname4_r");
if (fallback)
return fallback(name, pat, buffer, buflen, errnop, h_errnop, ttlp);
}
fail:
*errnop = -r;
*h_errnop = NO_RECOVERY;
return NSS_STATUS_UNAVAIL;
}