| /* SPDX-License-Identifier: LGPL-2.1-or-later */ |
| |
| #include <nss.h> |
| #include <pthread.h> |
| #include <string.h> |
| |
| #include "env-util.h" |
| #include "errno-util.h" |
| #include "fd-util.h" |
| #include "log.h" |
| #include "macro.h" |
| #include "nss-systemd.h" |
| #include "nss-util.h" |
| #include "pthread-util.h" |
| #include "signal-util.h" |
| #include "strv.h" |
| #include "user-record-nss.h" |
| #include "user-util.h" |
| #include "userdb-glue.h" |
| #include "userdb.h" |
| |
| static const struct passwd root_passwd = { |
| .pw_name = (char*) "root", |
| .pw_passwd = (char*) PASSWORD_SEE_SHADOW, |
| .pw_uid = 0, |
| .pw_gid = 0, |
| .pw_gecos = (char*) "Super User", |
| .pw_dir = (char*) "/root", |
| .pw_shell = (char*) "/bin/sh", |
| }; |
| |
| static const struct spwd root_spwd = { |
| .sp_namp = (char*) "root", |
| .sp_pwdp = (char*) PASSWORD_LOCKED_AND_INVALID, |
| .sp_lstchg = -1, |
| .sp_min = -1, |
| .sp_max = -1, |
| .sp_warn = -1, |
| .sp_inact = -1, |
| .sp_expire = -1, |
| .sp_flag = ULONG_MAX, /* this appears to be what everybody does ... */ |
| }; |
| |
| static const struct passwd nobody_passwd = { |
| .pw_name = (char*) NOBODY_USER_NAME, |
| .pw_passwd = (char*) PASSWORD_LOCKED_AND_INVALID, |
| .pw_uid = UID_NOBODY, |
| .pw_gid = GID_NOBODY, |
| .pw_gecos = (char*) "User Nobody", |
| .pw_dir = (char*) "/", |
| .pw_shell = (char*) NOLOGIN, |
| }; |
| |
| static const struct spwd nobody_spwd = { |
| .sp_namp = (char*) NOBODY_USER_NAME, |
| .sp_pwdp = (char*) PASSWORD_LOCKED_AND_INVALID, |
| .sp_lstchg = -1, |
| .sp_min = -1, |
| .sp_max = -1, |
| .sp_warn = -1, |
| .sp_inact = -1, |
| .sp_expire = -1, |
| .sp_flag = ULONG_MAX, /* this appears to be what everybody does ... */ |
| }; |
| |
| static const struct group root_group = { |
| .gr_name = (char*) "root", |
| .gr_gid = 0, |
| .gr_passwd = (char*) PASSWORD_SEE_SHADOW, |
| .gr_mem = (char*[]) { NULL }, |
| }; |
| |
| static const struct sgrp root_sgrp = { |
| .sg_namp = (char*) "root", |
| .sg_passwd = (char*) PASSWORD_LOCKED_AND_INVALID, |
| }; |
| |
| static const struct group nobody_group = { |
| .gr_name = (char*) NOBODY_GROUP_NAME, |
| .gr_gid = GID_NOBODY, |
| .gr_passwd = (char*) PASSWORD_LOCKED_AND_INVALID, |
| .gr_mem = (char*[]) { NULL }, |
| }; |
| |
| static const struct sgrp nobody_sgrp = { |
| .sg_namp = (char*) NOBODY_GROUP_NAME, |
| .sg_passwd = (char*) PASSWORD_LOCKED_AND_INVALID, |
| }; |
| |
| typedef struct GetentData { |
| /* As explained in NOTES section of getpwent_r(3) as 'getpwent_r() is not really reentrant since it |
| * shares the reading position in the stream with all other threads', we need to protect the data in |
| * UserDBIterator from multithreaded programs which may call setpwent(), getpwent_r(), or endpwent() |
| * simultaneously. So, each function locks the data by using the mutex below. */ |
| pthread_mutex_t mutex; |
| UserDBIterator *iterator; |
| |
| /* Applies to group iterations only: true while we iterate over groups defined through NSS, false |
| * otherwise. */ |
| bool by_membership; |
| } GetentData; |
| |
| static GetentData getpwent_data = { |
| .mutex = PTHREAD_MUTEX_INITIALIZER, |
| }; |
| |
| static GetentData getgrent_data = { |
| .mutex = PTHREAD_MUTEX_INITIALIZER, |
| }; |
| |
| static GetentData getspent_data = { |
| .mutex = PTHREAD_MUTEX_INITIALIZER, |
| }; |
| |
| static GetentData getsgent_data = { |
| .mutex = PTHREAD_MUTEX_INITIALIZER, |
| }; |
| |
| static void setup_logging_once(void) { |
| static pthread_once_t once = PTHREAD_ONCE_INIT; |
| assert_se(pthread_once(&once, log_parse_environment_variables) == 0); |
| } |
| |
| #define NSS_ENTRYPOINT_BEGIN \ |
| BLOCK_SIGNALS(NSS_SIGNALS_BLOCK); \ |
| setup_logging_once() |
| |
| NSS_GETPW_PROTOTYPES(systemd); |
| NSS_GETSP_PROTOTYPES(systemd); |
| NSS_GETGR_PROTOTYPES(systemd); |
| NSS_GETSG_PROTOTYPES(systemd); |
| NSS_PWENT_PROTOTYPES(systemd); |
| NSS_SPENT_PROTOTYPES(systemd); |
| NSS_GRENT_PROTOTYPES(systemd); |
| NSS_SGENT_PROTOTYPES(systemd); |
| NSS_INITGROUPS_PROTOTYPE(systemd); |
| |
| /* Since our NSS functions implement reentrant glibc APIs, we have to guarantee |
| * all the string pointers we return point into the buffer provided by the |
| * caller, not into our own static memory. */ |
| |
| static enum nss_status copy_synthesized_passwd( |
| struct passwd *dest, |
| const struct passwd *src, |
| char *buffer, size_t buflen, |
| int *errnop) { |
| |
| size_t required; |
| |
| assert(dest); |
| assert(src); |
| assert(src->pw_name); |
| assert(src->pw_passwd); |
| assert(src->pw_gecos); |
| assert(src->pw_dir); |
| assert(src->pw_shell); |
| |
| required = strlen(src->pw_name) + 1; |
| required += strlen(src->pw_passwd) + 1; |
| required += strlen(src->pw_gecos) + 1; |
| required += strlen(src->pw_dir) + 1; |
| required += strlen(src->pw_shell) + 1; |
| |
| if (buflen < required) { |
| *errnop = ERANGE; |
| return NSS_STATUS_TRYAGAIN; |
| } |
| |
| assert(buffer); |
| |
| *dest = *src; |
| |
| /* String fields point into the user-provided buffer */ |
| dest->pw_name = buffer; |
| dest->pw_passwd = stpcpy(dest->pw_name, src->pw_name) + 1; |
| dest->pw_gecos = stpcpy(dest->pw_passwd, src->pw_passwd) + 1; |
| dest->pw_dir = stpcpy(dest->pw_gecos, src->pw_gecos) + 1; |
| dest->pw_shell = stpcpy(dest->pw_dir, src->pw_dir) + 1; |
| strcpy(dest->pw_shell, src->pw_shell); |
| |
| return NSS_STATUS_SUCCESS; |
| } |
| |
| static enum nss_status copy_synthesized_spwd( |
| struct spwd *dest, |
| const struct spwd *src, |
| char *buffer, size_t buflen, |
| int *errnop) { |
| |
| size_t required; |
| |
| assert(dest); |
| assert(src); |
| assert(src->sp_namp); |
| assert(src->sp_pwdp); |
| |
| required = strlen(src->sp_namp) + 1; |
| required += strlen(src->sp_pwdp) + 1; |
| |
| if (buflen < required) { |
| *errnop = ERANGE; |
| return NSS_STATUS_TRYAGAIN; |
| } |
| |
| assert(buffer); |
| |
| *dest = *src; |
| |
| /* String fields point into the user-provided buffer */ |
| dest->sp_namp = buffer; |
| dest->sp_pwdp = stpcpy(dest->sp_namp, src->sp_namp) + 1; |
| strcpy(dest->sp_pwdp, src->sp_pwdp); |
| |
| return NSS_STATUS_SUCCESS; |
| } |
| |
| static enum nss_status copy_synthesized_group( |
| struct group *dest, |
| const struct group *src, |
| char *buffer, size_t buflen, |
| int *errnop) { |
| |
| size_t required; |
| |
| assert(dest); |
| assert(src); |
| assert(src->gr_name); |
| assert(src->gr_passwd); |
| assert(src->gr_mem); |
| assert(!*src->gr_mem); /* Our synthesized records' gr_mem is always just NULL... */ |
| |
| required = strlen(src->gr_name) + 1; |
| required += strlen(src->gr_passwd) + 1; |
| required += sizeof(char*); /* ...but that NULL still needs to be stored into the buffer! */ |
| |
| if (buflen < ALIGN(required)) { |
| *errnop = ERANGE; |
| return NSS_STATUS_TRYAGAIN; |
| } |
| |
| assert(buffer); |
| |
| *dest = *src; |
| |
| /* String fields point into the user-provided buffer */ |
| dest->gr_name = buffer; |
| dest->gr_passwd = stpcpy(dest->gr_name, src->gr_name) + 1; |
| dest->gr_mem = ALIGN_PTR(stpcpy(dest->gr_passwd, src->gr_passwd) + 1); |
| *dest->gr_mem = NULL; |
| |
| return NSS_STATUS_SUCCESS; |
| } |
| |
| static enum nss_status copy_synthesized_sgrp( |
| struct sgrp *dest, |
| const struct sgrp *src, |
| char *buffer, size_t buflen, |
| int *errnop) { |
| |
| size_t required; |
| |
| assert(dest); |
| assert(src); |
| assert(src->sg_namp); |
| assert(src->sg_passwd); |
| |
| required = strlen(src->sg_namp) + 1; |
| required += strlen(src->sg_passwd) + 1; |
| |
| if (buflen < required) { |
| *errnop = ERANGE; |
| return NSS_STATUS_TRYAGAIN; |
| } |
| |
| assert(buffer); |
| |
| *dest = *src; |
| |
| /* String fields point into the user-provided buffer */ |
| dest->sg_namp = buffer; |
| dest->sg_passwd = stpcpy(dest->sg_namp, src->sg_namp) + 1; |
| strcpy(dest->sg_passwd, src->sg_passwd); |
| |
| return NSS_STATUS_SUCCESS; |
| } |
| |
| enum nss_status _nss_systemd_getpwnam_r( |
| const char *name, |
| struct passwd *pwd, |
| char *buffer, size_t buflen, |
| int *errnop) { |
| |
| enum nss_status status; |
| int e; |
| |
| PROTECT_ERRNO; |
| NSS_ENTRYPOINT_BEGIN; |
| |
| assert(name); |
| assert(pwd); |
| assert(errnop); |
| |
| /* If the username is not valid, then we don't know it. Ideally libc would filter these for us |
| * anyway. We don't generate EINVAL here, because it isn't really out business to complain about |
| * invalid user names. */ |
| if (!valid_user_group_name(name, VALID_USER_RELAX)) |
| return NSS_STATUS_NOTFOUND; |
| |
| /* Synthesize entries for the root and nobody users, in case they are missing in /etc/passwd */ |
| if (getenv_bool_secure("SYSTEMD_NSS_BYPASS_SYNTHETIC") <= 0) { |
| |
| if (streq(name, root_passwd.pw_name)) |
| return copy_synthesized_passwd(pwd, &root_passwd, buffer, buflen, errnop); |
| |
| if (streq(name, nobody_passwd.pw_name)) { |
| if (!synthesize_nobody()) |
| return NSS_STATUS_NOTFOUND; |
| |
| return copy_synthesized_passwd(pwd, &nobody_passwd, buffer, buflen, errnop); |
| } |
| |
| } else if (STR_IN_SET(name, root_passwd.pw_name, nobody_passwd.pw_name)) |
| return NSS_STATUS_NOTFOUND; |
| |
| status = userdb_getpwnam(name, pwd, buffer, buflen, &e); |
| if (IN_SET(status, NSS_STATUS_UNAVAIL, NSS_STATUS_TRYAGAIN)) { |
| UNPROTECT_ERRNO; |
| *errnop = e; |
| return status; |
| } |
| |
| return status; |
| } |
| |
| enum nss_status _nss_systemd_getpwuid_r( |
| uid_t uid, |
| struct passwd *pwd, |
| char *buffer, size_t buflen, |
| int *errnop) { |
| |
| enum nss_status status; |
| int e; |
| |
| PROTECT_ERRNO; |
| NSS_ENTRYPOINT_BEGIN; |
| |
| assert(pwd); |
| assert(errnop); |
| |
| if (!uid_is_valid(uid)) |
| return NSS_STATUS_NOTFOUND; |
| |
| /* Synthesize data for the root user and for nobody in case they are missing from /etc/passwd */ |
| if (getenv_bool_secure("SYSTEMD_NSS_BYPASS_SYNTHETIC") <= 0) { |
| |
| if (uid == root_passwd.pw_uid) |
| return copy_synthesized_passwd(pwd, &root_passwd, buffer, buflen, errnop); |
| |
| if (uid == nobody_passwd.pw_uid) { |
| if (!synthesize_nobody()) |
| return NSS_STATUS_NOTFOUND; |
| |
| return copy_synthesized_passwd(pwd, &nobody_passwd, buffer, buflen, errnop); |
| } |
| |
| } else if (uid == root_passwd.pw_uid || uid == nobody_passwd.pw_uid) |
| return NSS_STATUS_NOTFOUND; |
| |
| status = userdb_getpwuid(uid, pwd, buffer, buflen, &e); |
| if (IN_SET(status, NSS_STATUS_UNAVAIL, NSS_STATUS_TRYAGAIN)) { |
| UNPROTECT_ERRNO; |
| *errnop = e; |
| return status; |
| } |
| |
| return status; |
| } |
| |
| enum nss_status _nss_systemd_getspnam_r( |
| const char *name, |
| struct spwd *spwd, |
| char *buffer, size_t buflen, |
| int *errnop) { |
| |
| enum nss_status status; |
| int e; |
| |
| PROTECT_ERRNO; |
| NSS_ENTRYPOINT_BEGIN; |
| |
| assert(name); |
| assert(spwd); |
| assert(errnop); |
| |
| if (!valid_user_group_name(name, VALID_USER_RELAX)) |
| return NSS_STATUS_NOTFOUND; |
| |
| /* Synthesize entries for the root and nobody users, in case they are missing in /etc/passwd */ |
| if (getenv_bool_secure("SYSTEMD_NSS_BYPASS_SYNTHETIC") <= 0) { |
| |
| if (streq(name, root_spwd.sp_namp)) |
| return copy_synthesized_spwd(spwd, &root_spwd, buffer, buflen, errnop); |
| |
| if (streq(name, nobody_spwd.sp_namp)) { |
| if (!synthesize_nobody()) |
| return NSS_STATUS_NOTFOUND; |
| |
| return copy_synthesized_spwd(spwd, &nobody_spwd, buffer, buflen, errnop); |
| } |
| |
| } else if (STR_IN_SET(name, root_spwd.sp_namp, nobody_spwd.sp_namp)) |
| return NSS_STATUS_NOTFOUND; |
| |
| status = userdb_getspnam(name, spwd, buffer, buflen, &e); |
| if (IN_SET(status, NSS_STATUS_UNAVAIL, NSS_STATUS_TRYAGAIN)) { |
| UNPROTECT_ERRNO; |
| *errnop = e; |
| return status; |
| } |
| |
| return status; |
| } |
| |
| #pragma GCC diagnostic ignored "-Wsizeof-pointer-memaccess" |
| |
| enum nss_status _nss_systemd_getgrnam_r( |
| const char *name, |
| struct group *gr, |
| char *buffer, size_t buflen, |
| int *errnop) { |
| |
| enum nss_status status; |
| int e; |
| |
| PROTECT_ERRNO; |
| NSS_ENTRYPOINT_BEGIN; |
| |
| assert(name); |
| assert(gr); |
| assert(errnop); |
| |
| if (!valid_user_group_name(name, VALID_USER_RELAX)) |
| return NSS_STATUS_NOTFOUND; |
| |
| /* Synthesize records for root and nobody, in case they are missing from /etc/group */ |
| if (getenv_bool_secure("SYSTEMD_NSS_BYPASS_SYNTHETIC") <= 0) { |
| |
| if (streq(name, root_group.gr_name)) |
| return copy_synthesized_group(gr, &root_group, buffer, buflen, errnop); |
| |
| if (streq(name, nobody_group.gr_name)) { |
| if (!synthesize_nobody()) |
| return NSS_STATUS_NOTFOUND; |
| |
| return copy_synthesized_group(gr, &nobody_group, buffer, buflen, errnop); |
| } |
| |
| } else if (STR_IN_SET(name, root_group.gr_name, nobody_group.gr_name)) |
| return NSS_STATUS_NOTFOUND; |
| |
| status = userdb_getgrnam(name, gr, buffer, buflen, &e); |
| if (IN_SET(status, NSS_STATUS_UNAVAIL, NSS_STATUS_TRYAGAIN)) { |
| UNPROTECT_ERRNO; |
| *errnop = e; |
| return status; |
| } |
| |
| return status; |
| } |
| |
| enum nss_status _nss_systemd_getgrgid_r( |
| gid_t gid, |
| struct group *gr, |
| char *buffer, size_t buflen, |
| int *errnop) { |
| |
| enum nss_status status; |
| int e; |
| |
| PROTECT_ERRNO; |
| NSS_ENTRYPOINT_BEGIN; |
| |
| assert(gr); |
| assert(errnop); |
| |
| if (!gid_is_valid(gid)) |
| return NSS_STATUS_NOTFOUND; |
| |
| /* Synthesize records for root and nobody, in case they are missing from /etc/group */ |
| if (getenv_bool_secure("SYSTEMD_NSS_BYPASS_SYNTHETIC") <= 0) { |
| |
| if (gid == root_group.gr_gid) |
| return copy_synthesized_group(gr, &root_group, buffer, buflen, errnop); |
| |
| if (gid == nobody_group.gr_gid) { |
| if (!synthesize_nobody()) |
| return NSS_STATUS_NOTFOUND; |
| |
| return copy_synthesized_group(gr, &nobody_group, buffer, buflen, errnop); |
| } |
| |
| } else if (gid == root_group.gr_gid || gid == nobody_group.gr_gid) |
| return NSS_STATUS_NOTFOUND; |
| |
| status = userdb_getgrgid(gid, gr, buffer, buflen, &e); |
| if (IN_SET(status, NSS_STATUS_UNAVAIL, NSS_STATUS_TRYAGAIN)) { |
| UNPROTECT_ERRNO; |
| *errnop = e; |
| return status; |
| } |
| |
| return status; |
| } |
| |
| enum nss_status _nss_systemd_getsgnam_r( |
| const char *name, |
| struct sgrp *sgrp, |
| char *buffer, size_t buflen, |
| int *errnop) { |
| |
| enum nss_status status; |
| int e; |
| |
| PROTECT_ERRNO; |
| NSS_ENTRYPOINT_BEGIN; |
| |
| assert(name); |
| assert(sgrp); |
| assert(errnop); |
| |
| if (!valid_user_group_name(name, VALID_USER_RELAX)) |
| return NSS_STATUS_NOTFOUND; |
| |
| /* Synthesize records for root and nobody, in case they are missing from /etc/group */ |
| if (getenv_bool_secure("SYSTEMD_NSS_BYPASS_SYNTHETIC") <= 0) { |
| |
| if (streq(name, root_sgrp.sg_namp)) |
| return copy_synthesized_sgrp(sgrp, &root_sgrp, buffer, buflen, errnop); |
| |
| if (streq(name, nobody_sgrp.sg_namp)) { |
| if (!synthesize_nobody()) |
| return NSS_STATUS_NOTFOUND; |
| |
| return copy_synthesized_sgrp(sgrp, &nobody_sgrp, buffer, buflen, errnop); |
| } |
| |
| } else if (STR_IN_SET(name, root_sgrp.sg_namp, nobody_sgrp.sg_namp)) |
| return NSS_STATUS_NOTFOUND; |
| |
| status = userdb_getsgnam(name, sgrp, buffer, buflen, &e); |
| if (IN_SET(status, NSS_STATUS_UNAVAIL, NSS_STATUS_TRYAGAIN)) { |
| UNPROTECT_ERRNO; |
| *errnop = e; |
| return status; |
| } |
| |
| return status; |
| } |
| |
| static enum nss_status nss_systemd_endent(GetentData *p) { |
| PROTECT_ERRNO; |
| NSS_ENTRYPOINT_BEGIN; |
| |
| assert(p); |
| |
| _cleanup_(pthread_mutex_unlock_assertp) pthread_mutex_t *_l = pthread_mutex_lock_assert(&p->mutex); |
| (void) _l; /* make llvm shut up about _l not being used. */ |
| |
| p->iterator = userdb_iterator_free(p->iterator); |
| p->by_membership = false; |
| |
| return NSS_STATUS_SUCCESS; |
| } |
| |
| enum nss_status _nss_systemd_endpwent(void) { |
| return nss_systemd_endent(&getpwent_data); |
| } |
| |
| enum nss_status _nss_systemd_endspent(void) { |
| return nss_systemd_endent(&getspent_data); |
| } |
| |
| enum nss_status _nss_systemd_endgrent(void) { |
| return nss_systemd_endent(&getgrent_data); |
| } |
| |
| enum nss_status _nss_systemd_endsgent(void) { |
| return nss_systemd_endent(&getsgent_data); |
| } |
| |
| enum nss_status _nss_systemd_setpwent(int stayopen) { |
| int r; |
| |
| PROTECT_ERRNO; |
| NSS_ENTRYPOINT_BEGIN; |
| |
| if (_nss_systemd_is_blocked()) |
| return NSS_STATUS_NOTFOUND; |
| |
| _cleanup_(pthread_mutex_unlock_assertp) pthread_mutex_t *_l = pthread_mutex_lock_assert(&getpwent_data.mutex); |
| (void) _l; /* make llvm shut up about _l not being used. */ |
| |
| getpwent_data.iterator = userdb_iterator_free(getpwent_data.iterator); |
| getpwent_data.by_membership = false; |
| |
| /* Don't synthesize root/nobody when iterating. Let nss-files take care of that. If the two records |
| * are missing there, then that's fine, after all getpwent() is known to be possibly incomplete |
| * (think: LDAP/NIS type situations), and our synthesizing of root/nobody is a robustness fallback |
| * only, which matters for getpwnam()/getpwuid() primarily, which are the main NSS entrypoints to the |
| * user database. */ |
| r = userdb_all(nss_glue_userdb_flags() | USERDB_DONT_SYNTHESIZE, &getpwent_data.iterator); |
| return r < 0 ? NSS_STATUS_UNAVAIL : NSS_STATUS_SUCCESS; |
| } |
| |
| enum nss_status _nss_systemd_setgrent(int stayopen) { |
| int r; |
| |
| PROTECT_ERRNO; |
| NSS_ENTRYPOINT_BEGIN; |
| |
| if (_nss_systemd_is_blocked()) |
| return NSS_STATUS_NOTFOUND; |
| |
| _cleanup_(pthread_mutex_unlock_assertp) pthread_mutex_t *_l = pthread_mutex_lock_assert(&getgrent_data.mutex); |
| (void) _l; /* make llvm shut up about _l not being used. */ |
| |
| getgrent_data.iterator = userdb_iterator_free(getgrent_data.iterator); |
| getgrent_data.by_membership = false; |
| |
| /* See _nss_systemd_setpwent() for an explanation why we use USERDB_DONT_SYNTHESIZE here */ |
| r = groupdb_all(nss_glue_userdb_flags() | USERDB_DONT_SYNTHESIZE, &getgrent_data.iterator); |
| return r < 0 ? NSS_STATUS_UNAVAIL : NSS_STATUS_SUCCESS; |
| } |
| |
| enum nss_status _nss_systemd_setspent(int stayopen) { |
| int r; |
| |
| PROTECT_ERRNO; |
| NSS_ENTRYPOINT_BEGIN; |
| |
| if (_nss_systemd_is_blocked()) |
| return NSS_STATUS_NOTFOUND; |
| |
| _cleanup_(pthread_mutex_unlock_assertp) pthread_mutex_t *_l = pthread_mutex_lock_assert(&getspent_data.mutex); |
| (void) _l; /* make llvm shut up about _l not being used. */ |
| |
| getspent_data.iterator = userdb_iterator_free(getspent_data.iterator); |
| getspent_data.by_membership = false; |
| |
| /* See _nss_systemd_setpwent() for an explanation why we use USERDB_DONT_SYNTHESIZE here */ |
| r = userdb_all(nss_glue_userdb_flags() | USERDB_DONT_SYNTHESIZE, &getspent_data.iterator); |
| return r < 0 ? NSS_STATUS_UNAVAIL : NSS_STATUS_SUCCESS; |
| } |
| |
| enum nss_status _nss_systemd_setsgent(int stayopen) { |
| int r; |
| |
| PROTECT_ERRNO; |
| NSS_ENTRYPOINT_BEGIN; |
| |
| if (_nss_systemd_is_blocked()) |
| return NSS_STATUS_NOTFOUND; |
| |
| _cleanup_(pthread_mutex_unlock_assertp) pthread_mutex_t *_l = pthread_mutex_lock_assert(&getsgent_data.mutex); |
| (void) _l; /* make llvm shut up about _l not being used. */ |
| |
| getsgent_data.iterator = userdb_iterator_free(getsgent_data.iterator); |
| getsgent_data.by_membership = false; |
| |
| /* See _nss_systemd_setpwent() for an explanation why we use USERDB_DONT_SYNTHESIZE here */ |
| r = groupdb_all(nss_glue_userdb_flags() | USERDB_DONT_SYNTHESIZE, &getsgent_data.iterator); |
| return r < 0 ? NSS_STATUS_UNAVAIL : NSS_STATUS_SUCCESS; |
| } |
| |
| enum nss_status _nss_systemd_getpwent_r( |
| struct passwd *result, |
| char *buffer, size_t buflen, |
| int *errnop) { |
| |
| _cleanup_(user_record_unrefp) UserRecord *ur = NULL; |
| int r; |
| |
| PROTECT_ERRNO; |
| NSS_ENTRYPOINT_BEGIN; |
| |
| assert(result); |
| assert(errnop); |
| |
| if (_nss_systemd_is_blocked()) |
| return NSS_STATUS_NOTFOUND; |
| |
| _cleanup_(pthread_mutex_unlock_assertp) pthread_mutex_t *_l = pthread_mutex_lock_assert(&getpwent_data.mutex); |
| (void) _l; /* make llvm shut up about _l not being used. */ |
| |
| if (!getpwent_data.iterator) { |
| UNPROTECT_ERRNO; |
| *errnop = EHOSTDOWN; |
| return NSS_STATUS_UNAVAIL; |
| } |
| |
| r = userdb_iterator_get(getpwent_data.iterator, &ur); |
| if (r == -ESRCH) |
| return NSS_STATUS_NOTFOUND; |
| if (r < 0) { |
| UNPROTECT_ERRNO; |
| *errnop = -r; |
| return NSS_STATUS_UNAVAIL; |
| } |
| |
| r = nss_pack_user_record(ur, result, buffer, buflen); |
| if (r < 0) { |
| UNPROTECT_ERRNO; |
| *errnop = -r; |
| return NSS_STATUS_TRYAGAIN; |
| } |
| |
| return NSS_STATUS_SUCCESS; |
| } |
| |
| enum nss_status _nss_systemd_getgrent_r( |
| struct group *result, |
| char *buffer, size_t buflen, |
| int *errnop) { |
| |
| _cleanup_(group_record_unrefp) GroupRecord *gr = NULL; |
| _cleanup_free_ char **members = NULL; |
| int r; |
| |
| PROTECT_ERRNO; |
| NSS_ENTRYPOINT_BEGIN; |
| |
| assert(result); |
| assert(errnop); |
| |
| if (_nss_systemd_is_blocked()) |
| return NSS_STATUS_NOTFOUND; |
| |
| _cleanup_(pthread_mutex_unlock_assertp) pthread_mutex_t *_l = pthread_mutex_lock_assert(&getgrent_data.mutex); |
| (void) _l; /* make llvm shut up about _l not being used. */ |
| |
| if (!getgrent_data.iterator) { |
| UNPROTECT_ERRNO; |
| *errnop = EHOSTDOWN; |
| return NSS_STATUS_UNAVAIL; |
| } |
| |
| if (!getgrent_data.by_membership) { |
| r = groupdb_iterator_get(getgrent_data.iterator, &gr); |
| if (r == -ESRCH) { |
| /* So we finished iterating native groups now. Let's now continue with iterating |
| * native memberships, and generate additional group entries for any groups |
| * referenced there that are defined in NSS only. This means for those groups there |
| * will be two or more entries generated during iteration, but this is apparently how |
| * this is supposed to work, and what other implementations do too. Clients are |
| * supposed to merge the group records found during iteration automatically. */ |
| getgrent_data.iterator = userdb_iterator_free(getgrent_data.iterator); |
| |
| r = membershipdb_all(nss_glue_userdb_flags(), &getgrent_data.iterator); |
| if (r < 0 && r != -ESRCH) { |
| UNPROTECT_ERRNO; |
| *errnop = -r; |
| return NSS_STATUS_UNAVAIL; |
| } |
| |
| getgrent_data.by_membership = true; |
| } else if (r < 0) { |
| UNPROTECT_ERRNO; |
| *errnop = -r; |
| return NSS_STATUS_UNAVAIL; |
| } else if (!STR_IN_SET(gr->group_name, root_group.gr_name, nobody_group.gr_name)) { |
| r = membershipdb_by_group_strv(gr->group_name, nss_glue_userdb_flags(), &members); |
| if (r < 0 && r != -ESRCH) { |
| UNPROTECT_ERRNO; |
| *errnop = -r; |
| return NSS_STATUS_UNAVAIL; |
| } |
| } |
| } |
| |
| if (getgrent_data.by_membership) { |
| _cleanup_(_nss_systemd_unblockp) bool blocked = false; |
| |
| if (!getgrent_data.iterator) |
| return NSS_STATUS_NOTFOUND; |
| |
| for (;;) { |
| _cleanup_free_ char *user_name = NULL, *group_name = NULL; |
| |
| r = membershipdb_iterator_get(getgrent_data.iterator, &user_name, &group_name); |
| if (r == -ESRCH) |
| return NSS_STATUS_NOTFOUND; |
| if (r < 0) { |
| UNPROTECT_ERRNO; |
| *errnop = -r; |
| return NSS_STATUS_UNAVAIL; |
| } |
| |
| if (STR_IN_SET(user_name, root_passwd.pw_name, nobody_passwd.pw_name)) |
| continue; |
| if (STR_IN_SET(group_name, root_group.gr_name, nobody_group.gr_name)) |
| continue; |
| |
| /* We are about to recursively call into NSS, let's make sure we disable recursion into our own code. */ |
| if (!blocked) { |
| r = _nss_systemd_block(true); |
| if (r < 0) { |
| UNPROTECT_ERRNO; |
| *errnop = -r; |
| return NSS_STATUS_UNAVAIL; |
| } |
| |
| blocked = true; |
| } |
| |
| r = nss_group_record_by_name(group_name, false, &gr); |
| if (r == -ESRCH) |
| continue; |
| if (r < 0) { |
| log_debug_errno(r, "Failed to do NSS check for group '%s', ignoring: %m", group_name); |
| continue; |
| } |
| |
| members = strv_new(user_name); |
| if (!members) { |
| UNPROTECT_ERRNO; |
| *errnop = ENOMEM; |
| return NSS_STATUS_TRYAGAIN; |
| } |
| |
| /* Note that we currently generate one group entry per user that is part of a |
| * group. It's a bit ugly, but equivalent to generating a single entry with a set of |
| * members in them. */ |
| break; |
| } |
| } |
| |
| r = nss_pack_group_record(gr, members, result, buffer, buflen); |
| if (r < 0) { |
| UNPROTECT_ERRNO; |
| *errnop = -r; |
| return NSS_STATUS_TRYAGAIN; |
| } |
| |
| return NSS_STATUS_SUCCESS; |
| } |
| |
| enum nss_status _nss_systemd_getspent_r( |
| struct spwd *result, |
| char *buffer, size_t buflen, |
| int *errnop) { |
| |
| _cleanup_(user_record_unrefp) UserRecord *ur = NULL; |
| int r; |
| |
| PROTECT_ERRNO; |
| NSS_ENTRYPOINT_BEGIN; |
| |
| assert(result); |
| assert(errnop); |
| |
| if (_nss_systemd_is_blocked()) |
| return NSS_STATUS_NOTFOUND; |
| |
| _cleanup_(pthread_mutex_unlock_assertp) pthread_mutex_t *_l = pthread_mutex_lock_assert(&getspent_data.mutex); |
| (void) _l; /* make llvm shut up about _l not being used. */ |
| |
| if (!getspent_data.iterator) { |
| UNPROTECT_ERRNO; |
| *errnop = EHOSTDOWN; |
| return NSS_STATUS_UNAVAIL; |
| } |
| |
| for (;;) { |
| r = userdb_iterator_get(getspent_data.iterator, &ur); |
| if (r == -ESRCH) |
| return NSS_STATUS_NOTFOUND; |
| if (r < 0) { |
| UNPROTECT_ERRNO; |
| *errnop = -r; |
| return NSS_STATUS_UNAVAIL; |
| } |
| |
| if (!ur->incomplete) /* don't synthesize shadow records for records where we couldn't read shadow data */ |
| break; |
| |
| ur = user_record_unref(ur); |
| } |
| |
| r = nss_pack_user_record_shadow(ur, result, buffer, buflen); |
| if (r < 0) { |
| UNPROTECT_ERRNO; |
| *errnop = -r; |
| return NSS_STATUS_TRYAGAIN; |
| } |
| |
| return NSS_STATUS_SUCCESS; |
| } |
| |
| enum nss_status _nss_systemd_getsgent_r( |
| struct sgrp *result, |
| char *buffer, size_t buflen, |
| int *errnop) { |
| |
| _cleanup_(group_record_unrefp) GroupRecord *gr = NULL; |
| int r; |
| |
| PROTECT_ERRNO; |
| NSS_ENTRYPOINT_BEGIN; |
| |
| assert(result); |
| assert(errnop); |
| |
| if (_nss_systemd_is_blocked()) |
| return NSS_STATUS_NOTFOUND; |
| |
| _cleanup_(pthread_mutex_unlock_assertp) pthread_mutex_t *_l = pthread_mutex_lock_assert(&getsgent_data.mutex); |
| (void) _l; /* make llvm shut up about _l not being used. */ |
| |
| if (!getsgent_data.iterator) { |
| UNPROTECT_ERRNO; |
| *errnop = EHOSTDOWN; |
| return NSS_STATUS_UNAVAIL; |
| } |
| |
| for (;;) { |
| r = groupdb_iterator_get(getsgent_data.iterator, &gr); |
| if (r == -ESRCH) |
| return NSS_STATUS_NOTFOUND; |
| if (r < 0) { |
| UNPROTECT_ERRNO; |
| *errnop = -r; |
| return NSS_STATUS_UNAVAIL; |
| } |
| |
| if (!gr->incomplete) /* don't synthesize shadow records for records where we couldn't read shadow data */ |
| break; |
| |
| gr = group_record_unref(gr); |
| } |
| |
| r = nss_pack_group_record_shadow(gr, result, buffer, buflen); |
| if (r < 0) { |
| UNPROTECT_ERRNO; |
| *errnop = -r; |
| return NSS_STATUS_TRYAGAIN; |
| } |
| |
| return NSS_STATUS_SUCCESS; |
| } |
| |
| enum nss_status _nss_systemd_initgroups_dyn( |
| const char *user_name, |
| gid_t gid, |
| long *start, |
| long *size, |
| gid_t **groupsp, |
| long int limit, |
| int *errnop) { |
| |
| _cleanup_(userdb_iterator_freep) UserDBIterator *iterator = NULL; |
| bool any = false; |
| int r; |
| |
| PROTECT_ERRNO; |
| NSS_ENTRYPOINT_BEGIN; |
| |
| assert(user_name); |
| assert(start); |
| assert(size); |
| assert(groupsp); |
| assert(errnop); |
| |
| if (!valid_user_group_name(user_name, VALID_USER_RELAX)) |
| return NSS_STATUS_NOTFOUND; |
| |
| /* Don't allow extending these two special users, the same as we won't resolve them via getpwnam() */ |
| if (STR_IN_SET(user_name, root_passwd.pw_name, nobody_passwd.pw_name)) |
| return NSS_STATUS_NOTFOUND; |
| |
| if (_nss_systemd_is_blocked()) |
| return NSS_STATUS_NOTFOUND; |
| |
| r = membershipdb_by_user(user_name, nss_glue_userdb_flags(), &iterator); |
| if (r < 0) { |
| UNPROTECT_ERRNO; |
| *errnop = -r; |
| return NSS_STATUS_UNAVAIL; |
| } |
| |
| for (;;) { |
| _cleanup_(group_record_unrefp) GroupRecord *g = NULL; |
| _cleanup_free_ char *group_name = NULL; |
| |
| r = membershipdb_iterator_get(iterator, NULL, &group_name); |
| if (r == -ESRCH) |
| break; |
| if (r < 0) { |
| UNPROTECT_ERRNO; |
| *errnop = -r; |
| return NSS_STATUS_UNAVAIL; |
| } |
| |
| /* The group might be defined via traditional NSS only, hence let's do a full look-up without |
| * disabling NSS. This means we are operating recursively here. */ |
| |
| r = groupdb_by_name(group_name, (nss_glue_userdb_flags() & ~USERDB_EXCLUDE_NSS) | USERDB_SUPPRESS_SHADOW, &g); |
| if (r == -ESRCH) |
| continue; |
| if (r < 0) { |
| log_debug_errno(r, "Failed to resolve group '%s', ignoring: %m", group_name); |
| continue; |
| } |
| |
| if (g->gid == gid) |
| continue; |
| |
| if (*start >= *size) { |
| gid_t *new_groups; |
| long new_size; |
| |
| if (limit > 0 && *size >= limit) /* Reached the limit.? */ |
| break; |
| |
| if (*size > LONG_MAX/2) { /* Check for overflow */ |
| UNPROTECT_ERRNO; |
| *errnop = ENOMEM; |
| return NSS_STATUS_TRYAGAIN; |
| } |
| |
| new_size = *start * 2; |
| if (limit > 0 && new_size > limit) |
| new_size = limit; |
| |
| /* Enlarge buffer */ |
| new_groups = reallocarray(*groupsp, new_size, sizeof(**groupsp)); |
| if (!new_groups) { |
| UNPROTECT_ERRNO; |
| *errnop = ENOMEM; |
| return NSS_STATUS_TRYAGAIN; |
| } |
| |
| *groupsp = new_groups; |
| *size = new_size; |
| } |
| |
| (*groupsp)[(*start)++] = g->gid; |
| any = true; |
| } |
| |
| return any ? NSS_STATUS_SUCCESS : NSS_STATUS_NOTFOUND; |
| } |
| |
| static thread_local unsigned _blocked = 0; |
| |
| _public_ int _nss_systemd_block(bool b) { |
| |
| /* This blocks recursively: it's blocked for as many times this function is called with `true` until |
| * it is called an equal time with `false`. */ |
| |
| if (b) { |
| if (_blocked >= UINT_MAX) |
| return -EOVERFLOW; |
| |
| _blocked++; |
| } else { |
| if (_blocked <= 0) |
| return -EOVERFLOW; |
| |
| _blocked--; |
| } |
| |
| return b; /* Return what is passed in, i.e. the new state from the PoV of the caller */ |
| } |
| |
| _public_ bool _nss_systemd_is_blocked(void) { |
| return _blocked > 0; |
| } |
