From f743c82d11ffafa1a48f9b7108eff072ecc9ab1c Mon Sep 17 00:00:00 2001

From: Sumit Bose <sbose@redhat.com>

Date: Tue, 9 Oct 2018 13:25:35 +0200

Subject: [PATCH 47/47] PAM: return short name for files provider users

If the 'allow_missing_name' option is used with pam_sss and the user

name will be determined based on the certificate content and the mapping

rules the PAM responder will by default return the fully-qualified name

of the user which is then later used by other PAM modules as well.

For local users which are configured to use SSSD for Smartcard

authentication this might cause issues in other PAM modules because they

are not aware of the fully-qualified name and will treat the user as

unknown.

With this patch the PAM responder will return the short name for all

users handled by the files provider.

Related to https://pagure.io/SSSD/sssd/issue/3848

Reviewed-by: Jakub Hrozek <jhrozek@redhat.com>

(cherry picked from commit dbd717fe5b7d8dd640b6ade435b49edb3db5280a)

---

 src/responder/pam/pamsrv.h     |  3 ++-

 src/responder/pam/pamsrv_cmd.c | 13 +++++++++----

 src/responder/pam/pamsrv_p11.c | 32 +++++++++++++++++++++++++++++---

 3 files changed, 40 insertions(+), 8 deletions(-)

diff --git a/src/responder/pam/pamsrv.h b/src/responder/pam/pamsrv.h

index 60aa97967456b9b7ab35e64f103c1c9a17bef3a9..3a927bb39b1e03735c237cc6b5a33234c2f4e2ef 100644

--- a/src/responder/pam/pamsrv.h

+++ b/src/responder/pam/pamsrv.h

@@ -108,7 +108,8 @@ struct tevent_req *pam_check_cert_send(TALLOC_CTX *mem_ctx,

 errno_t pam_check_cert_recv(struct tevent_req *req, TALLOC_CTX *mem_ctx,

                             struct cert_auth_info **cert_list);

-errno_t add_pam_cert_response(struct pam_data *pd, const char *sysdb_username,

+errno_t add_pam_cert_response(struct pam_data *pd, struct sss_domain_info *dom,

+                              const char *sysdb_username,

                               struct cert_auth_info *cert_info,

                               enum response_type type);

diff --git a/src/responder/pam/pamsrv_cmd.c b/src/responder/pam/pamsrv_cmd.c

index a22afd225894872847a0fb13e202f927fd2ae124..553bf8fbbdb485f4a7b2610b894b1a78b4e47317 100644

--- a/src/responder/pam/pamsrv_cmd.c

+++ b/src/responder/pam/pamsrv_cmd.c

@@ -1645,7 +1645,8 @@ static void pam_forwarder_lookup_by_cert_done(struct tevent_req *req)

                      preq->current_cert != NULL;

                      preq->current_cert = sss_cai_get_next(preq->current_cert)) {

-                    ret = add_pam_cert_response(preq->pd, "",

+                    ret = add_pam_cert_response(preq->pd,

+                                       preq->cctx->rctx->domains, "",

                                        preq->current_cert,

                                        preq->cctx->rctx->domains->user_name_hint

                                             ? SSS_PAM_CERT_INFO_WITH_HINT

@@ -1699,7 +1700,8 @@ static void pam_forwarder_lookup_by_cert_done(struct tevent_req *req)

             if (preq->cctx->rctx->domains->user_name_hint

                     && preq->pd->cmd == SSS_PAM_PREAUTH) {

-                ret = add_pam_cert_response(preq->pd, cert_user,

+                ret = add_pam_cert_response(preq->pd,

+                                            preq->cctx->rctx->domains, cert_user,

                                             preq->cert_list,

                                             SSS_PAM_CERT_INFO_WITH_HINT);

                 preq->pd->pam_status = PAM_SUCCESS;

@@ -1725,7 +1727,8 @@ static void pam_forwarder_lookup_by_cert_done(struct tevent_req *req)

              * SSS_PAM_CERT_INFO message to send the name to the caller. */

             if (preq->pd->cmd == SSS_PAM_AUTHENTICATE

                     && preq->pd->logon_name == NULL) {

-                ret = add_pam_cert_response(preq->pd, cert_user,

+                ret = add_pam_cert_response(preq->pd,

+                                            preq->cctx->rctx->domains, cert_user,

                                             preq->cert_list,

                                             SSS_PAM_CERT_INFO);

                 if (ret != EOK) {

@@ -2117,7 +2120,9 @@ static void pam_dom_forwarder(struct pam_auth_req *preq)

                                   "the backend.\n");

                         }

-                        ret = add_pam_cert_response(preq->pd, cert_user,

+                        ret = add_pam_cert_response(preq->pd,

+                                                    preq->cctx->rctx->domains,

+                                                    cert_user,

                                                     preq->current_cert,

                                                     SSS_PAM_CERT_INFO);

                         if (ret != EOK) {

diff --git a/src/responder/pam/pamsrv_p11.c b/src/responder/pam/pamsrv_p11.c

index 491bd2b01d7bf9137b37c35f9da9eca1eed95a6d..785b29c99a65ec7167b31f746fd9a897b038d817 100644

--- a/src/responder/pam/pamsrv_p11.c

+++ b/src/responder/pam/pamsrv_p11.c

@@ -1145,7 +1145,8 @@ static errno_t pack_cert_data(TALLOC_CTX *mem_ctx, const char *sysdb_username,

  * used when running gdm-password. */

 #define PKCS11_LOGIN_TOKEN_ENV_NAME "PKCS11_LOGIN_TOKEN_NAME"

-errno_t add_pam_cert_response(struct pam_data *pd, const char *sysdb_username,

+errno_t add_pam_cert_response(struct pam_data *pd, struct sss_domain_info *dom,

+                              const char *sysdb_username,

                               struct cert_auth_info *cert_info,

                               enum response_type type)

 {

@@ -1153,6 +1154,10 @@ errno_t add_pam_cert_response(struct pam_data *pd, const char *sysdb_username,

     char *env = NULL;

     size_t msg_len;

     int ret;

+    char *short_name = NULL;

+    char *domain_name = NULL;

+    const char *cert_info_name = sysdb_username;

+

     if (type != SSS_PAM_CERT_INFO && type != SSS_PAM_CERT_INFO_WITH_HINT) {

         DEBUG(SSSDBG_CRIT_FAILURE, "Invalid response type [%d].\n", type);

@@ -1174,9 +1179,30 @@ errno_t add_pam_cert_response(struct pam_data *pd, const char *sysdb_username,

      * Smartcard. If this type of name is irritating at the PIN prompt or the

      * re_expression config option was set in a way that user@domain cannot be

      * handled anymore some more logic has to be added here. But for the time

-     * being I think using sysdb_username is fine. */

+     * being I think using sysdb_username is fine.

+     * As special case is the files provider which handles local users which

+     * by definition only have a short name. To avoid confusion by other

+     * modules on the PAM stack the short name is returned in this case. */

-    ret = pack_cert_data(pd, sysdb_username, cert_info, &msg, &msg_len);

+    if (sysdb_username != NULL) {

+        ret = sss_parse_internal_fqname(pd, sysdb_username,

+                                        &short_name, &domain_name);

+        if (ret != EOK) {

+            DEBUG(SSSDBG_CRIT_FAILURE, "Unable to parse name '%s' [%d]: %s, "

+                                       "using full name.\n",

+                                        sysdb_username, ret, sss_strerror(ret));

+        } else {

+            if (domain_name != NULL

+                    &&  is_files_provider(find_domain_by_name(dom, domain_name,

+                                                              false))) {

+                cert_info_name = short_name;

+            }

+        }

+    }

+

+    ret = pack_cert_data(pd, cert_info_name, cert_info, &msg, &msg_len);

+    talloc_free(short_name);

+    talloc_free(domain_name);

     if (ret != EOK) {

         DEBUG(SSSDBG_OP_FAILURE, "pack_cert_data failed.\n");

         return ret;

-- 

2.14.4