| /* SPDX-License-Identifier: LGPL-2.1+ */ |
| |
| #include <netdb.h> |
| #include <nss.h> |
| |
| #include "sd-bus.h" |
| #include "sd-login.h" |
| |
| #include "alloc-util.h" |
| #include "bus-common-errors.h" |
| #include "env-util.h" |
| #include "hostname-util.h" |
| #include "in-addr-util.h" |
| #include "macro.h" |
| #include "nss-util.h" |
| #include "signal-util.h" |
| #include "string-util.h" |
| #include "user-util.h" |
| #include "util.h" |
| |
| NSS_GETHOSTBYNAME_PROTOTYPES(mymachines); |
| NSS_GETPW_PROTOTYPES(mymachines); |
| NSS_GETGR_PROTOTYPES(mymachines); |
| |
| #define HOST_UID_LIMIT ((uid_t) UINT32_C(0x10000)) |
| #define HOST_GID_LIMIT ((gid_t) UINT32_C(0x10000)) |
| |
| static int count_addresses(sd_bus_message *m, int af, unsigned *ret) { |
| unsigned c = 0; |
| int r; |
| |
| assert(m); |
| assert(ret); |
| |
| while ((r = sd_bus_message_enter_container(m, 'r', "iay")) > 0) { |
| int family; |
| |
| r = sd_bus_message_read(m, "i", &family); |
| if (r < 0) |
| return r; |
| |
| r = sd_bus_message_skip(m, "ay"); |
| if (r < 0) |
| return r; |
| |
| r = sd_bus_message_exit_container(m); |
| if (r < 0) |
| return r; |
| |
| if (af != AF_UNSPEC && family != af) |
| continue; |
| |
| c++; |
| } |
| if (r < 0) |
| return r; |
| |
| r = sd_bus_message_rewind(m, false); |
| if (r < 0) |
| return r; |
| |
| *ret = c; |
| return 0; |
| } |
| |
| enum nss_status _nss_mymachines_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_first = NULL; |
| _cleanup_(sd_bus_message_unrefp) sd_bus_message* reply = NULL; |
| _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL; |
| _cleanup_free_ int *ifindices = NULL; |
| _cleanup_free_ char *class = NULL; |
| size_t l, ms, idx; |
| unsigned i = 0, c = 0; |
| char *r_name; |
| int n_ifindices, r; |
| |
| PROTECT_ERRNO; |
| BLOCK_SIGNALS(NSS_SIGNALS_BLOCK); |
| |
| assert(name); |
| assert(pat); |
| assert(buffer); |
| assert(errnop); |
| assert(h_errnop); |
| |
| r = sd_machine_get_class(name, &class); |
| if (r < 0) |
| goto fail; |
| if (!streq(class, "container")) { |
| r = -ENOTTY; |
| goto fail; |
| } |
| |
| n_ifindices = sd_machine_get_ifindices(name, &ifindices); |
| if (n_ifindices < 0) { |
| r = n_ifindices; |
| goto fail; |
| } |
| |
| r = sd_bus_open_system(&bus); |
| if (r < 0) |
| goto fail; |
| |
| r = sd_bus_call_method(bus, |
| "org.freedesktop.machine1", |
| "/org/freedesktop/machine1", |
| "org.freedesktop.machine1.Manager", |
| "GetMachineAddresses", |
| NULL, |
| &reply, |
| "s", name); |
| if (r < 0) |
| goto fail; |
| |
| r = sd_bus_message_enter_container(reply, 'a', "(iay)"); |
| if (r < 0) |
| goto fail; |
| |
| r = count_addresses(reply, AF_UNSPEC, &c); |
| if (r < 0) |
| goto fail; |
| |
| if (c <= 0) { |
| *h_errnop = HOST_NOT_FOUND; |
| return NSS_STATUS_NOTFOUND; |
| } |
| |
| l = strlen(name); |
| ms = ALIGN(l+1) + ALIGN(sizeof(struct gaih_addrtuple)) * c; |
| if (buflen < ms) { |
| UNPROTECT_ERRNO; |
| *errnop = ERANGE; |
| *h_errnop = NETDB_INTERNAL; |
| return NSS_STATUS_TRYAGAIN; |
| } |
| |
| /* First, append name */ |
| r_name = buffer; |
| memcpy(r_name, name, 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', "iay")) > 0) { |
| int family; |
| const void *a; |
| size_t sz; |
| |
| r = sd_bus_message_read(reply, "i", &family); |
| if (r < 0) |
| 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)) { |
| r = -EAFNOSUPPORT; |
| goto fail; |
| } |
| |
| 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 = n_ifindices == 1 ? ifindices[0] : 0; |
| memcpy(r_tuple->addr, a, sz); |
| |
| idx += ALIGN(sizeof(struct gaih_addrtuple)); |
| i++; |
| } |
| |
| assert(i == c); |
| |
| r = sd_bus_message_exit_container(reply); |
| if (r < 0) |
| goto fail; |
| |
| assert(idx == ms); |
| |
| if (*pat) |
| **pat = *r_tuple_first; |
| else |
| *pat = r_tuple_first; |
| |
| 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; |
| |
| fail: |
| UNPROTECT_ERRNO; |
| *errnop = -r; |
| *h_errnop = NO_DATA; |
| return NSS_STATUS_UNAVAIL; |
| } |
| |
| enum nss_status _nss_mymachines_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* reply = NULL; |
| _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL; |
| _cleanup_free_ char *class = NULL; |
| unsigned c = 0, i = 0; |
| char *r_name, *r_aliases, *r_addr, *r_addr_list; |
| size_t l, idx, ms, alen; |
| int r; |
| |
| PROTECT_ERRNO; |
| BLOCK_SIGNALS(NSS_SIGNALS_BLOCK); |
| |
| assert(name); |
| assert(result); |
| assert(buffer); |
| assert(errnop); |
| assert(h_errnop); |
| |
| if (af == AF_UNSPEC) |
| af = AF_INET; |
| |
| if (af != AF_INET && af != AF_INET6) { |
| r = -EAFNOSUPPORT; |
| goto fail; |
| } |
| |
| r = sd_machine_get_class(name, &class); |
| if (r < 0) |
| goto fail; |
| if (!streq(class, "container")) { |
| r = -ENOTTY; |
| goto fail; |
| } |
| |
| r = sd_bus_open_system(&bus); |
| if (r < 0) |
| goto fail; |
| |
| r = sd_bus_call_method(bus, |
| "org.freedesktop.machine1", |
| "/org/freedesktop/machine1", |
| "org.freedesktop.machine1.Manager", |
| "GetMachineAddresses", |
| NULL, |
| &reply, |
| "s", name); |
| if (r < 0) |
| goto fail; |
| |
| r = sd_bus_message_enter_container(reply, 'a', "(iay)"); |
| if (r < 0) |
| goto fail; |
| |
| r = count_addresses(reply, af, &c); |
| if (r < 0) |
| goto fail; |
| |
| if (c <= 0) { |
| *h_errnop = HOST_NOT_FOUND; |
| return NSS_STATUS_NOTFOUND; |
| } |
| |
| alen = FAMILY_ADDRESS_SIZE(af); |
| l = strlen(name); |
| |
| ms = ALIGN(l+1) + c * ALIGN(alen) + (c+2) * sizeof(char*); |
| |
| if (buflen < ms) { |
| UNPROTECT_ERRNO; |
| *errnop = ERANGE; |
| *h_errnop = NETDB_INTERNAL; |
| return NSS_STATUS_TRYAGAIN; |
| } |
| |
| /* First, append name */ |
| r_name = buffer; |
| memcpy(r_name, name, l+1); |
| idx = ALIGN(l+1); |
| |
| /* Second, create 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', "iay")) > 0) { |
| int family; |
| const void *a; |
| size_t sz; |
| |
| r = sd_bus_message_read(reply, "i", &family); |
| if (r < 0) |
| 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++; |
| } |
| |
| assert(i == c); |
| idx += c * ALIGN(alen); |
| |
| r = sd_bus_message_exit_container(reply); |
| if (r < 0) |
| goto fail; |
| |
| /* Third, 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; |
| |
| if (ttlp) |
| *ttlp = 0; |
| |
| if (canonp) |
| *canonp = r_name; |
| |
| /* 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; |
| |
| fail: |
| UNPROTECT_ERRNO; |
| *errnop = -r; |
| *h_errnop = NO_DATA; |
| return NSS_STATUS_UNAVAIL; |
| } |
| |
| NSS_GETHOSTBYNAME_FALLBACKS(mymachines); |
| |
| enum nss_status _nss_mymachines_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; |
| const char *p, *e, *machine; |
| uint32_t mapped; |
| uid_t uid; |
| size_t l; |
| int r; |
| |
| PROTECT_ERRNO; |
| BLOCK_SIGNALS(NSS_SIGNALS_BLOCK); |
| |
| assert(name); |
| assert(pwd); |
| |
| p = startswith(name, "vu-"); |
| if (!p) |
| return NSS_STATUS_NOTFOUND; |
| |
| e = strrchr(p, '-'); |
| if (!e || e == p) |
| return NSS_STATUS_NOTFOUND; |
| |
| if (e - p > HOST_NAME_MAX - 1) /* -1 for the last dash */ |
| return NSS_STATUS_NOTFOUND; |
| |
| r = parse_uid(e + 1, &uid); |
| if (r < 0) |
| return NSS_STATUS_NOTFOUND; |
| |
| machine = strndupa(p, e - p); |
| if (!machine_name_is_valid(machine)) |
| return NSS_STATUS_NOTFOUND; |
| |
| if (getenv_bool_secure("SYSTEMD_NSS_BYPASS_BUS") > 0) |
| /* Make sure we can't deadlock if we are invoked by dbus-daemon. This way, it won't be able to resolve |
| * these UIDs, but that should be unproblematic as containers should never be able to connect to a bus |
| * running on the host. */ |
| return NSS_STATUS_NOTFOUND; |
| |
| r = sd_bus_open_system(&bus); |
| if (r < 0) |
| goto fail; |
| |
| r = sd_bus_call_method(bus, |
| "org.freedesktop.machine1", |
| "/org/freedesktop/machine1", |
| "org.freedesktop.machine1.Manager", |
| "MapFromMachineUser", |
| &error, |
| &reply, |
| "su", |
| machine, (uint32_t) uid); |
| if (r < 0) { |
| if (sd_bus_error_has_name(&error, BUS_ERROR_NO_SUCH_USER_MAPPING)) |
| return NSS_STATUS_NOTFOUND; |
| |
| goto fail; |
| } |
| |
| r = sd_bus_message_read(reply, "u", &mapped); |
| if (r < 0) |
| goto fail; |
| |
| /* Refuse to work if the mapped address is in the host UID range, or if there was no mapping at all. */ |
| if (mapped < HOST_UID_LIMIT || mapped == uid) |
| return NSS_STATUS_NOTFOUND; |
| |
| l = strlen(name); |
| if (buflen < l+1) { |
| UNPROTECT_ERRNO; |
| *errnop = ERANGE; |
| return NSS_STATUS_TRYAGAIN; |
| } |
| |
| memcpy(buffer, name, l+1); |
| |
| pwd->pw_name = buffer; |
| pwd->pw_uid = mapped; |
| pwd->pw_gid = GID_NOBODY; |
| pwd->pw_gecos = buffer; |
| pwd->pw_passwd = (char*) "*"; /* locked */ |
| pwd->pw_dir = (char*) "/"; |
| pwd->pw_shell = (char*) "/sbin/nologin"; |
| |
| return NSS_STATUS_SUCCESS; |
| |
| fail: |
| UNPROTECT_ERRNO; |
| *errnop = -r; |
| return NSS_STATUS_UNAVAIL; |
| } |
| |
| enum nss_status _nss_mymachines_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 *machine; |
| uint32_t mapped; |
| int r; |
| |
| PROTECT_ERRNO; |
| BLOCK_SIGNALS(NSS_SIGNALS_BLOCK); |
| |
| if (!uid_is_valid(uid)) |
| return NSS_STATUS_NOTFOUND; |
| |
| /* We consider all uids < 65536 host uids */ |
| if (uid < HOST_UID_LIMIT) |
| return NSS_STATUS_NOTFOUND; |
| |
| if (getenv_bool_secure("SYSTEMD_NSS_BYPASS_BUS") > 0) |
| return NSS_STATUS_NOTFOUND; |
| |
| r = sd_bus_open_system(&bus); |
| if (r < 0) |
| goto fail; |
| |
| r = sd_bus_call_method(bus, |
| "org.freedesktop.machine1", |
| "/org/freedesktop/machine1", |
| "org.freedesktop.machine1.Manager", |
| "MapToMachineUser", |
| &error, |
| &reply, |
| "u", |
| (uint32_t) uid); |
| if (r < 0) { |
| if (sd_bus_error_has_name(&error, BUS_ERROR_NO_SUCH_USER_MAPPING)) |
| return NSS_STATUS_NOTFOUND; |
| |
| goto fail; |
| } |
| |
| r = sd_bus_message_read(reply, "sou", &machine, NULL, &mapped); |
| if (r < 0) |
| goto fail; |
| |
| if (mapped == uid) |
| return NSS_STATUS_NOTFOUND; |
| |
| if (snprintf(buffer, buflen, "vu-%s-" UID_FMT, machine, (uid_t) mapped) >= (int) buflen) { |
| UNPROTECT_ERRNO; |
| *errnop = ERANGE; |
| return NSS_STATUS_TRYAGAIN; |
| } |
| |
| pwd->pw_name = buffer; |
| pwd->pw_uid = uid; |
| pwd->pw_gid = GID_NOBODY; |
| pwd->pw_gecos = buffer; |
| pwd->pw_passwd = (char*) "*"; /* locked */ |
| pwd->pw_dir = (char*) "/"; |
| pwd->pw_shell = (char*) "/sbin/nologin"; |
| |
| return NSS_STATUS_SUCCESS; |
| |
| fail: |
| UNPROTECT_ERRNO; |
| *errnop = -r; |
| return NSS_STATUS_UNAVAIL; |
| } |
| |
| #pragma GCC diagnostic ignored "-Wsizeof-pointer-memaccess" |
| |
| enum nss_status _nss_mymachines_getgrnam_r( |
| const char *name, |
| 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 *p, *e, *machine; |
| uint32_t mapped; |
| uid_t gid; |
| size_t l; |
| int r; |
| |
| PROTECT_ERRNO; |
| BLOCK_SIGNALS(NSS_SIGNALS_BLOCK); |
| |
| assert(name); |
| assert(gr); |
| |
| p = startswith(name, "vg-"); |
| if (!p) |
| return NSS_STATUS_NOTFOUND; |
| |
| e = strrchr(p, '-'); |
| if (!e || e == p) |
| return NSS_STATUS_NOTFOUND; |
| |
| if (e - p > HOST_NAME_MAX - 1) /* -1 for the last dash */ |
| return NSS_STATUS_NOTFOUND; |
| |
| r = parse_gid(e + 1, &gid); |
| if (r < 0) |
| return NSS_STATUS_NOTFOUND; |
| |
| machine = strndupa(p, e - p); |
| if (!machine_name_is_valid(machine)) |
| return NSS_STATUS_NOTFOUND; |
| |
| if (getenv_bool_secure("SYSTEMD_NSS_BYPASS_BUS") > 0) |
| return NSS_STATUS_NOTFOUND; |
| |
| r = sd_bus_open_system(&bus); |
| if (r < 0) |
| goto fail; |
| |
| r = sd_bus_call_method(bus, |
| "org.freedesktop.machine1", |
| "/org/freedesktop/machine1", |
| "org.freedesktop.machine1.Manager", |
| "MapFromMachineGroup", |
| &error, |
| &reply, |
| "su", |
| machine, (uint32_t) gid); |
| if (r < 0) { |
| if (sd_bus_error_has_name(&error, BUS_ERROR_NO_SUCH_GROUP_MAPPING)) |
| return NSS_STATUS_NOTFOUND; |
| |
| goto fail; |
| } |
| |
| r = sd_bus_message_read(reply, "u", &mapped); |
| if (r < 0) |
| goto fail; |
| |
| if (mapped < HOST_GID_LIMIT || mapped == gid) |
| return NSS_STATUS_NOTFOUND; |
| |
| l = sizeof(char*) + strlen(name) + 1; |
| if (buflen < l) { |
| UNPROTECT_ERRNO; |
| *errnop = ERANGE; |
| return NSS_STATUS_TRYAGAIN; |
| } |
| |
| memzero(buffer, sizeof(char*)); |
| strcpy(buffer + sizeof(char*), name); |
| |
| gr->gr_name = buffer + sizeof(char*); |
| gr->gr_gid = mapped; |
| gr->gr_passwd = (char*) "*"; /* locked */ |
| gr->gr_mem = (char**) buffer; |
| |
| return NSS_STATUS_SUCCESS; |
| |
| fail: |
| UNPROTECT_ERRNO; |
| *errnop = -r; |
| return NSS_STATUS_UNAVAIL; |
| } |
| |
| enum nss_status _nss_mymachines_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 *machine; |
| uint32_t mapped; |
| int r; |
| |
| PROTECT_ERRNO; |
| BLOCK_SIGNALS(NSS_SIGNALS_BLOCK); |
| |
| if (!gid_is_valid(gid)) |
| return NSS_STATUS_NOTFOUND; |
| |
| /* We consider all gids < 65536 host gids */ |
| if (gid < HOST_GID_LIMIT) |
| return NSS_STATUS_NOTFOUND; |
| |
| if (getenv_bool_secure("SYSTEMD_NSS_BYPASS_BUS") > 0) |
| return NSS_STATUS_NOTFOUND; |
| |
| r = sd_bus_open_system(&bus); |
| if (r < 0) |
| goto fail; |
| |
| r = sd_bus_call_method(bus, |
| "org.freedesktop.machine1", |
| "/org/freedesktop/machine1", |
| "org.freedesktop.machine1.Manager", |
| "MapToMachineGroup", |
| &error, |
| &reply, |
| "u", |
| (uint32_t) gid); |
| if (r < 0) { |
| if (sd_bus_error_has_name(&error, BUS_ERROR_NO_SUCH_GROUP_MAPPING)) |
| return NSS_STATUS_NOTFOUND; |
| |
| goto fail; |
| } |
| |
| r = sd_bus_message_read(reply, "sou", &machine, NULL, &mapped); |
| if (r < 0) |
| goto fail; |
| |
| if (mapped == gid) |
| return NSS_STATUS_NOTFOUND; |
| |
| if (buflen < sizeof(char*) + 1) { |
| UNPROTECT_ERRNO; |
| *errnop = ERANGE; |
| return NSS_STATUS_TRYAGAIN; |
| } |
| |
| memzero(buffer, sizeof(char*)); |
| if (snprintf(buffer + sizeof(char*), buflen - sizeof(char*), "vg-%s-" GID_FMT, machine, (gid_t) mapped) >= (int) buflen) { |
| UNPROTECT_ERRNO; |
| *errnop = ERANGE; |
| return NSS_STATUS_TRYAGAIN; |
| } |
| |
| gr->gr_name = buffer + sizeof(char*); |
| gr->gr_gid = gid; |
| gr->gr_passwd = (char*) "*"; /* locked */ |
| gr->gr_mem = (char**) buffer; |
| |
| return NSS_STATUS_SUCCESS; |
| |
| fail: |
| UNPROTECT_ERRNO; |
| *errnop = -r; |
| return NSS_STATUS_UNAVAIL; |
| } |