From 2f30fe59d2b5b038160e00b02948b9521e60f9af Mon Sep 17 00:00:00 2001 From: Lukas Slebodnik Date: Wed, 20 Jan 2016 13:15:11 +0100 Subject: [PATCH] PAM: Allow to configure pam services for smartcards Resolves: https://fedorahosted.org/sssd/ticket/2926 --- src/confdb/confdb.h | 1 + src/config/SSSDConfig/__init__.py.in | 1 + src/config/etc/sssd.api.conf | 1 + src/man/sssd.conf.5.xml | 82 ++++++++++++++++++++ src/responder/pam/pamsrv_p11.c | 145 ++++++++++++++++++++++++++++++++++- 5 files changed, 227 insertions(+), 3 deletions(-) diff --git a/src/confdb/confdb.h b/src/confdb/confdb.h index fcffcb5a6ff8b3f766ed9a693db874c7c6e3d9b9..9e053305a70952c6076fb37c7a9a869c36e32b54 100644 --- a/src/confdb/confdb.h +++ b/src/confdb/confdb.h @@ -121,6 +121,7 @@ #define CONFDB_PAM_CERT_AUTH "pam_cert_auth" #define CONFDB_PAM_CERT_DB_PATH "pam_cert_db_path" #define CONFDB_PAM_P11_CHILD_TIMEOUT "p11_child_timeout" +#define CONFDB_PAM_P11_ALLOWED_SERVICES "pam_p11_allowed_services" /* SUDO */ #define CONFDB_SUDO_CONF_ENTRY "config/sudo" diff --git a/src/config/SSSDConfig/__init__.py.in b/src/config/SSSDConfig/__init__.py.in index 647d081255d738c028f73bc5d65eff58cebdbdf1..260e306a95b38dd1ec6cded10360fdb65074e44c 100644 --- a/src/config/SSSDConfig/__init__.py.in +++ b/src/config/SSSDConfig/__init__.py.in @@ -92,6 +92,7 @@ option_strings = { 'pam_public_domains' : _('List of domains accessible even for untrusted users.'), 'pam_account_expired_message' : _('Message printed when user account is expired.'), 'p11_child_timeout' : _('How many seconds will pam_sss wait for p11_child to finish'), + 'pam_p11_allowed_services' : _('Allowed services for using smartcards'), # [sudo] 'sudo_timed' : _('Whether to evaluate the time-based attributes in sudo rules'), diff --git a/src/config/etc/sssd.api.conf b/src/config/etc/sssd.api.conf index 89cf8634ffb8115d9e65cf66dc9b1ed630415c15..74dc588ad0a68aaad9708b45143ffdc9ae90aeb1 100644 --- a/src/config/etc/sssd.api.conf +++ b/src/config/etc/sssd.api.conf @@ -62,6 +62,7 @@ pam_trusted_users = str, None, false pam_public_domains = str, None, false pam_account_expired_message = str, None, false p11_child_timeout = int, None, false +pam_p11_allowed_services = str, None, false [sudo] # sudo service diff --git a/src/man/sssd.conf.5.xml b/src/man/sssd.conf.5.xml index 73a21bfa0049bc4d3cfacb49201707868c87e533..8d45b9229035d510fc46e7067459b38512892f42 100644 --- a/src/man/sssd.conf.5.xml +++ b/src/man/sssd.conf.5.xml @@ -1051,6 +1051,88 @@ pam_account_expired_message = Account expired, please call help desk. + + pam_p11_allowed_services (integer) + + + A comma-separated list of PAM service names for + which will be alloed to use smartcards. + How many seconds will pam_sss wait for + p11_child to finish. + + + it is possibel to add another PAM service name to + the default set by using + +service_name or to explicitly + remove a PAM service name from the default set by + using -service_name. For example, + in order to replace a default PAM service name for + this logon right (e.g. login) with + a custom pam service name (e.g. + my_pam_service), + you would use the following configuration: + +pam_p11_allowed_services = +my_pam_service, -login + + + + Default: the default set of PAM service names + includes: + + + + login + + + + + su + + + + + su-l + + + + + gdm-smartcard + + + + + gdm-password + + + + + gnome-screensaver + + + + + kdm + + + + + sudo + + + + + sudo-i + + + + + gdm-smartcard + + + + + + diff --git a/src/responder/pam/pamsrv_p11.c b/src/responder/pam/pamsrv_p11.c index ad1670136dbf8efc41df6950af744ff8b06e6a11..f836c96453cfb9ac24fe86e83ca5267784b51d7e 100644 --- a/src/responder/pam/pamsrv_p11.c +++ b/src/responder/pam/pamsrv_p11.c @@ -40,12 +40,141 @@ errno_t p11_child_init(struct pam_ctx *pctx) return child_debug_init(P11_CHILD_LOG_FILE, &pctx->p11_child_debug_fd); } +static inline bool +service_in_list(char **list, size_t nlist, const char *str) +{ + size_t i; + + for (i = 0; i < nlist; i++) { + if (strcasecmp(list[i], str) == 0) { + break; + } + } + + return (i < nlist) ? true : false; +} + +static errno_t get_sc_services(TALLOC_CTX *mem_ctx, struct pam_ctx *pctx, + char ***_sc_list) +{ + TALLOC_CTX *tmp_ctx; + errno_t ret; + char *conf_str; + char **conf_list; + int conf_list_size; + char **add_list; + char **remove_list; + int ai = 0; + int ri = 0; + int j = 0; + char **sc_list; + int expected_sc_list_size; + + const char *default_sc_services[] = { + "login", "su", "su-l", "gdm-smartcard", "gdm-password", "kdm", "sudo", + "sudo-i", "gnome-screensaver", NULL, + }; + const int default_sc_services_size = + sizeof(default_sc_services) / sizeof(default_sc_services[0]); + + tmp_ctx = talloc_new(mem_ctx); + if (tmp_ctx == NULL) { + return ENOMEM; + } + + ret = confdb_get_string(pctx->rctx->cdb, tmp_ctx, CONFDB_PAC_CONF_ENTRY, + CONFDB_PAM_P11_ALLOWED_SERVICES, NULL, + &conf_str); + if (ret != EOK) { + DEBUG(SSSDBG_CRIT_FAILURE, + "confdb_get_string failed %d [%s]\n", ret, sss_strerror(ret)); + goto done; + } + + if (conf_str != NULL) { + ret = split_on_separator(tmp_ctx, conf_str, ',', true, true, + &conf_list, &conf_list_size); + if (ret != EOK) { + DEBUG(SSSDBG_CRIT_FAILURE, + "Cannot parse list of service names '%s': %d [%s]\n", + conf_str, ret, sss_strerror(ret)); + goto done; + } + } else { + conf_list = talloc_zero_array(tmp_ctx, char *, 1); + conf_list_size = 1; + } + + add_list = talloc_zero_array(tmp_ctx, char *, conf_list_size); + remove_list = talloc_zero_array(tmp_ctx, char *, conf_list_size); + + if (add_list == NULL || remove_list == NULL) { + ret = ENOMEM; + goto done; + } + + for (int i = 0; conf_list[i] != NULL; ++i) { + switch (conf_list[i][0]) { + case '+': + add_list[ai] = conf_list[i] + 1; + ++ai; + break; + case '-': + remove_list[ri] = remove_list[i] + 1; + ++ri; + break; + default: + DEBUG(SSSDBG_OP_FAILURE, + "The option "CONFDB_PAM_P11_ALLOWED_SERVICES" must start" + "with either '+' (for adding service) or '-' (for " + "removing service) got '%s'\n", conf_list[i]); + ret = EINVAL; + goto done; + } + } + + expected_sc_list_size = default_sc_services_size + ai + 1; + + sc_list = talloc_zero_array(tmp_ctx, char *, expected_sc_list_size); + if (sc_list == NULL) { + ret = ENOMEM; + goto done; + } + + for (int i = 0; add_list[i] != NULL; ++i) { + if (service_in_list(remove_list, ri, add_list[i])) { + continue; + } + + sc_list[j] = talloc_strdup(sc_list, add_list[i]); + ++j; + } + + for (int i = 0; default_sc_services[i] != NULL; ++i) { + if (service_in_list(remove_list, ri, default_sc_services[i])) { + continue; + } + + sc_list[j] = talloc_strdup(sc_list, default_sc_services[i]); + ++j; + } + + if (_sc_list != NULL) { + *_sc_list = talloc_steal(mem_ctx, sc_list); + } + +done: + talloc_zfree(tmp_ctx); + + return ret; +} + bool may_do_cert_auth(struct pam_ctx *pctx, struct pam_data *pd) { size_t c; - const char *sc_services[] = { "login", "su", "su-l", "gdm-smartcard", - "gdm-password", "kdm", "sudo", "sudo-i", - "gnome-screensaver", NULL }; + errno_t ret; + char **sc_services = NULL; + if (!pctx->cert_auth) { return false; } @@ -64,6 +193,14 @@ bool may_do_cert_auth(struct pam_ctx *pctx, struct pam_data *pd) if (pd->service == NULL || *pd->service == '\0') { return false; } + + ret = get_sc_services(pctx, pctx, &sc_services); + if (ret != EOK) { + DEBUG(SSSDBG_CRIT_FAILURE, + "Failed to ged p11 allowed services %d[%s]", + ret, sss_strerror(ret)); + } + for (c = 0; sc_services[c] != NULL; c++) { if (strcmp(pd->service, sc_services[c]) == 0) { break; @@ -73,9 +210,11 @@ bool may_do_cert_auth(struct pam_ctx *pctx, struct pam_data *pd) DEBUG(SSSDBG_CRIT_FAILURE, "Smartcard authentication for service [%s] not supported.\n", pd->service); + talloc_zfree(sc_services); return false; } + talloc_zfree(sc_services); return true; } -- 2.5.0