#include <net/if.h>
#include <stdlib.h>
#include <arpa/inet.h>
+#include <dlfcn.h>
#include "sd-bus.h"
#include "bus-util.h"
#define DNS_CALL_TIMEOUT_USEC (45*USEC_PER_SEC)
-static int count_addresses(sd_bus_message *m, unsigned af, unsigned *ret) {
- unsigned c = 0;
- int r;
+typedef void (*voidfunc_t)(void);
+
+static voidfunc_t find_fallback(const char *module, const char *symbol) {
+ void *dl;
+
+ /* Try to find a fallback NSS module symbol */
+
+ dl = dlopen(module, RTLD_LAZY|RTLD_NODELETE);
+ if (!dl)
+ return NULL;
+
+ return dlsym(dl, symbol);
+}
+
+static bool bus_error_shall_fallback(sd_bus_error *e) {
+ return sd_bus_error_has_name(e, SD_BUS_ERROR_SERVICE_UNKNOWN) ||
+ sd_bus_error_has_name(e, SD_BUS_ERROR_NAME_HAS_NO_OWNER) ||
+ sd_bus_error_has_name(e, SD_BUS_ERROR_NO_REPLY) ||
+ sd_bus_error_has_name(e, SD_BUS_ERROR_ACCESS_DENIED);
+}
+
+static int count_addresses(sd_bus_message *m, int af, const char **canonical) {
+ int c = 0, r;
assert(m);
- assert(ret);
+ assert(canonical);
+
+ r = sd_bus_message_enter_container(m, 'a', "(iayi)");
+ if (r < 0)
+ return r;
- while ((r = sd_bus_message_enter_container(m, 'r', "yayi")) > 0) {
- unsigned char family;
+ while ((r = sd_bus_message_enter_container(m, 'r', "iayi")) > 0) {
+ int family;
- r = sd_bus_message_read(m, "y", &family);
+ r = sd_bus_message_read(m, "i", &family);
if (r < 0)
return r;
if (r < 0)
return r;
- r = sd_bus_message_rewind(m, false);
+ r = sd_bus_message_exit_container(m);
if (r < 0)
return r;
- *ret = c;
- return 0;
+ r = sd_bus_message_read(m, "s", canonical);
+ if (r < 0)
+ return r;
+
+ r = sd_bus_message_rewind(m, true);
+ if (r < 0)
+ return r;
+
+ return c;
}
enum nss_status _nss_resolve_gethostbyname4_r(
_cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
struct gaih_addrtuple *r_tuple, *r_tuple_first = NULL;
_cleanup_bus_unref_ sd_bus *bus = NULL;
+ const char *canonical = NULL;
size_t l, ms, idx;
char *r_name;
- unsigned i = 0, c = 0;
- int r;
+ int c, r, i = 0;
assert(name);
assert(pat);
if (r < 0)
goto fail;
- r = sd_bus_message_append(req, "sy", name, AF_UNSPEC);
+ r = sd_bus_message_append(req, "si", name, AF_UNSPEC);
if (r < 0)
goto fail;
return NSS_STATUS_NOTFOUND;
}
+ if (bus_error_shall_fallback(&error)) {
+
+ enum nss_status (*fallback)(
+ const char *name,
+ struct gaih_addrtuple **pat,
+ char *buffer, size_t buflen,
+ int *errnop, int *h_errnop,
+ int32_t *ttlp);
+
+ fallback = (enum nss_status (*)(const char *name,
+ struct gaih_addrtuple **pat,
+ char *buffer, size_t buflen,
+ int *errnop, int *h_errnop,
+ int32_t *ttlp))
+ find_fallback("libnss_dns.so.2", "_nss_dns_gethostbyname4_r");
+ if (fallback)
+ return fallback(name, pat, buffer, buflen, errnop, h_errnop, ttlp);
+ }
+
*errnop = -r;
*h_errnop = NO_RECOVERY;
return NSS_STATUS_UNAVAIL;
}
- r = sd_bus_message_enter_container(reply, 'a', "(yayi)");
- if (r < 0)
+ c = count_addresses(reply, AF_UNSPEC, &canonical);
+ if (c < 0) {
+ r = c;
goto fail;
-
- r = count_addresses(reply, AF_UNSPEC, &c);
- if (r < 0)
- goto fail;
-
- if (c <= 0) {
+ }
+ if (c == 0) {
*errnop = ESRCH;
*h_errnop = HOST_NOT_FOUND;
return NSS_STATUS_NOTFOUND;
}
- l = strlen(name);
+ if (isempty(canonical))
+ canonical = name;
+
+ l = strlen(canonical);
ms = ALIGN(l+1) + ALIGN(sizeof(struct gaih_addrtuple)) * c;
if (buflen < ms) {
*errnop = ENOMEM;
/* First, append name */
r_name = buffer;
- memcpy(r_name, name, l+1);
+ memcpy(r_name, canonical, l+1);
idx = ALIGN(l+1);
/* Second, append addresses */
r_tuple_first = (struct gaih_addrtuple*) (buffer + idx);
- while ((r = sd_bus_message_enter_container(reply, 'r', "yayi")) > 0) {
- unsigned char family;
+
+ r = sd_bus_message_enter_container(reply, 'a', "(iayi)");
+ if (r < 0)
+ goto fail;
+
+ while ((r = sd_bus_message_enter_container(reply, 'r', "iayi")) > 0) {
+ int family, ifindex;
const void *a;
- int ifindex;
size_t sz;
- r = sd_bus_message_read(reply, "y", &family);
+ r = sd_bus_message_read(reply, "i", &family);
if (r < 0)
goto fail;
if (!IN_SET(family, AF_INET, AF_INET6))
continue;
- if (sz != PROTO_ADDRESS_SIZE(family)) {
+ if (sz != FAMILY_ADDRESS_SIZE(family)) {
r = -EINVAL;
goto fail;
}
idx += ALIGN(sizeof(struct gaih_addrtuple));
i++;
}
-
- assert(i == c);
-
- r = sd_bus_message_exit_container(reply);
if (r < 0)
goto fail;
+ assert(i == c);
assert(idx == ms);
if (*pat)
_cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
char *r_name, *r_aliases, *r_addr, *r_addr_list;
_cleanup_bus_unref_ sd_bus *bus = NULL;
- unsigned c = 0, i = 0;
size_t l, idx, ms, alen;
- int r;
+ const char *canonical;
+ int c, r, i = 0;
assert(name);
assert(result);
if (r < 0)
goto fail;
- r = sd_bus_message_append(req, "sy", name, af);
+ r = sd_bus_message_append(req, "si", name, af);
if (r < 0)
goto fail;
return NSS_STATUS_NOTFOUND;
}
+ if (bus_error_shall_fallback(&error)) {
+
+ enum nss_status (*fallback)(
+ const char *name,
+ int af,
+ struct hostent *result,
+ char *buffer, size_t buflen,
+ int *errnop, int *h_errnop,
+ int32_t *ttlp,
+ char **canonp);
+
+ fallback = (enum nss_status (*)(const char *name,
+ int af,
+ struct hostent *result,
+ char *buffer, size_t buflen,
+ int *errnop, int *h_errnop,
+ int32_t *ttlp,
+ char **canonp))
+ find_fallback("libnss_dns.so.2", "_nss_dns_gethostbyname3_r");
+ if (fallback)
+ return fallback(name, af, result, buffer, buflen, errnop, h_errnop, ttlp, canonp);
+ }
+
*errnop = -r;
*h_errnop = NO_RECOVERY;
return NSS_STATUS_UNAVAIL;
}
- r = sd_bus_message_enter_container(reply, 'a', "(yayi)");
- if (r < 0)
- goto fail;
-
- r = count_addresses(reply, af, &c);
- if (r < 0)
+ c = count_addresses(reply, af, &canonical);
+ if (c < 0) {
+ r = c;
goto fail;
-
- if (c <= 0) {
+ }
+ if (c == 0) {
*errnop = ESRCH;
*h_errnop = HOST_NOT_FOUND;
return NSS_STATUS_NOTFOUND;
}
- alen = PROTO_ADDRESS_SIZE(af);
- l = strlen(name);
+ if (isempty(canonical))
+ canonical = name;
+
+ alen = FAMILY_ADDRESS_SIZE(af);
+ l = strlen(canonical);
ms = ALIGN(l+1) +
sizeof(char*) +
/* First, append name */
r_name = buffer;
- memcpy(r_name, name, l+1);
+ memcpy(r_name, canonical, l+1);
idx = ALIGN(l+1);
- /* Second, create aliases array */
+ /* Second, create empty aliases array */
r_aliases = buffer + idx;
((char**) r_aliases)[0] = NULL;
idx += sizeof(char*);
/* Third, append addresses */
r_addr = buffer + idx;
- while ((r = sd_bus_message_enter_container(reply, 'r', "yayi")) > 0) {
- unsigned char family;
+
+ r = sd_bus_message_enter_container(reply, 'a', "(iayi)");
+ if (r < 0)
+ goto fail;
+
+ while ((r = sd_bus_message_enter_container(reply, 'r', "iayi")) > 0) {
+ int family, ifindex;
const void *a;
- int ifindex;
size_t sz;
- r = sd_bus_message_read(reply, "y", &family);
+ r = sd_bus_message_read(reply, "i", &family);
if (r < 0)
goto fail;
memcpy(r_addr + i*ALIGN(alen), a, alen);
i++;
}
+ if (r < 0)
+ goto fail;
assert(i == c);
idx += c * ALIGN(alen);
- r = sd_bus_message_exit_container(reply);
- if (r < 0)
- goto fail;
-
- /* Third, append address pointer array */
+ /* 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);
return NSS_STATUS_UNAVAIL;
}
- if (len != PROTO_ADDRESS_SIZE(af)) {
+ if (len != FAMILY_ADDRESS_SIZE(af)) {
*errnop = EINVAL;
*h_errnop = NO_RECOVERY;
return NSS_STATUS_UNAVAIL;
if (r < 0)
goto fail;
- r = sd_bus_message_append(req, "y", af);
+ r = sd_bus_message_append(req, "i", af);
if (r < 0)
goto fail;
return NSS_STATUS_NOTFOUND;
}
+ if (bus_error_shall_fallback(&error)) {
+
+ enum nss_status (*fallback)(
+ const void* addr, socklen_t len,
+ int af,
+ struct hostent *result,
+ char *buffer, size_t buflen,
+ int *errnop, int *h_errnop,
+ int32_t *ttlp);
+
+ fallback = (enum nss_status (*)(
+ const void* addr, socklen_t len,
+ int af,
+ struct hostent *result,
+ char *buffer, size_t buflen,
+ int *errnop, int *h_errnop,
+ int32_t *ttlp))
+ find_fallback("libnss_dns.so.2", "_nss_dns_gethostbyaddr2_r");
+
+ if (fallback)
+ return fallback(addr, len, af, result, buffer, buflen, errnop, h_errnop, ttlp);
+ }
+
*errnop = -r;
*h_errnop = NO_RECOVERY;
return NSS_STATUS_UNAVAIL;
idx += ALIGN(l+1);
}
+ if (r < 0)
+ goto fail;
((char**) r_aliases)[c-1] = NULL;
assert(idx == ms);
~ianmdlvl / elogind.git / blobdiff