Fix error in parsing multiple groups

Revert to use 'cn' for group names
Implement getgrent()

4 files changed, 346 insertions, 29 deletions

diff --git a/server/nss/nss_ldb.h b/server/nss/nss_ldb.h
index 13e5a672..fe135683 100644
--- a/server/nss/nss_ldb.h
+++ b/server/nss/nss_ldb.h
@@ -9,7 +9,7 @@
 #define NSS_PWUID_FILTER "(&(objectclass=user)(uidNumber=%llu))"
 #define NSS_PWENT_FILTER "(objectclass=user)"
 
-#define NSS_GRNAM_FILTER "(&(objectclass=group)(gid=%s))"
+#define NSS_GRNAM_FILTER "(&(objectclass=group)(cn=%s))"
 #define NSS_GRNA2_FILTER "(&(objectclass=user)(memberof=%s))"
 #define NSS_GRGID_FILTER "(&(objectclass=group)(gidNumber=%llu))"
 #define NSS_GRENT_FILTER "(objectclass=group)"
diff --git a/server/nss/nsssrv_cmd.c b/server/nss/nsssrv_cmd.c
index 6252ab4a..c69598bc 100644
--- a/server/nss/nsssrv_cmd.c
+++ b/server/nss/nsssrv_cmd.c
@@ -494,6 +494,7 @@ static int fill_grent(struct nss_packet *packet,
     rp = 2*sizeof(uint32_t);
 
     num = 0;
+    mnump = 0;
     for (i = 0; i < count; i++) {
         msg = msgs[i];
 
@@ -535,6 +536,7 @@ static int fill_grent(struct nss_packet *packet,
              * set next element to be a group, and eventually
              * fail there if here start bogus entries */
             get_group = true;
+            i--;
             nss_packet_get_body(packet, &body, &blen);
             ((uint32_t *)(&body[mnump]))[0] = memnum; /* num members */
             continue;
@@ -555,8 +557,10 @@ static int fill_grent(struct nss_packet *packet,
     }
 
     /* fill in the last group member count */
-    nss_packet_get_body(packet, &body, &blen);
-    ((uint32_t *)(&body[mnump]))[0] = memnum; /* num members */
+    if (mnump != 0) {
+        nss_packet_get_body(packet, &body, &blen);
+        ((uint32_t *)(&body[mnump]))[0] = memnum; /* num members */
+    }
 
 done:
     nss_packet_get_body(packet, &body, &blen);
@@ -668,6 +672,216 @@ static int nss_cmd_getgrgid(struct cli_ctx *cctx)
     return ret;
 }
 
+/* to keep it simple at this stage we are retrieving the
+ * full enumeration again for each request for each process
+ * and we also block on setpwent() for the full time needed
+ * to retrieve the data. And endpwent() frees all the data.
+ * Next steps are:
+ * - use and nsssrv wide cache with data already structured
+ *   so that it can be immediately returned (see nscd way)
+ * - use mutexes so that setpwent() can return immediately
+ *   even if the data is still being fetched
+ * - make getpwent() wait on the mutex
+ */
+static int nss_cmd_setgrent_callback(void *ptr, int status,
+                                     struct ldb_result *res)
+{
+    struct nss_cmd_ctx *nctx = talloc_get_type(ptr, struct nss_cmd_ctx);
+    struct cli_ctx *cctx = nctx->cctx;
+    struct getent_ctx *gctx = cctx->gctx;
+    int ret;
+
+    /* create response packet */
+    ret = nss_packet_new(cctx->creq, 0,
+                         nss_packet_get_cmd(cctx->creq->in),
+                         &cctx->creq->out);
+    if (ret != EOK) {
+        return ret;
+    }
+
+    if (status != LDB_SUCCESS) {
+        nss_packet_set_error(cctx->creq->out, status);
+        goto done;
+    }
+
+    gctx->grps = talloc_steal(gctx, res);
+
+done:
+    nss_cmd_done(nctx);
+    return EOK;
+}
+
+static int nss_cmd_setgrent(struct cli_ctx *cctx)
+{
+    struct nss_cmd_ctx *nctx;
+    struct getent_ctx *gctx;
+    int ret;
+
+    nctx = talloc(cctx, struct nss_cmd_ctx);
+    if (!nctx) {
+        return ENOMEM;
+    }
+    nctx->cctx = cctx;
+
+    if (cctx->gctx == NULL) {
+        gctx = talloc_zero(cctx, struct getent_ctx);
+        if (!gctx) {
+            talloc_free(nctx);
+            return ENOMEM;
+        }
+        cctx->gctx = gctx;
+    }
+    if (cctx->gctx->grps) {
+        talloc_free(cctx->gctx->grps);
+        cctx->gctx->grps = NULL;
+        cctx->gctx->grp_cur = 0;
+    }
+
+    ret = nss_ldb_enumgrent(nctx, cctx->ev, cctx->ldb,
+                            nss_cmd_setgrent_callback, nctx);
+
+    return ret;
+}
+
+static int nss_cmd_retgrent(struct cli_ctx *cctx, int num)
+{
+    struct getent_ctx *gctx = cctx->gctx;
+    int n, ret;
+
+    n = gctx->grps->count - gctx->grp_cur;
+    if (n > num) n = num;
+
+    ret = fill_grent(cctx->creq->out, &(gctx->grps->msgs[gctx->grp_cur]), n);
+    gctx->grp_cur += n;
+
+    return ret;
+}
+
+/* used only if a process calls getpwent() without first calling setpwent()
+ * in this case we basically trigger an implicit setpwent() */
+static int nss_cmd_getgrent_callback(void *ptr, int status,
+                                     struct ldb_result *res)
+{
+    struct nss_cmd_ctx *nctx = talloc_get_type(ptr, struct nss_cmd_ctx);
+    struct cli_ctx *cctx = nctx->cctx;
+    struct getent_ctx *gctx = cctx->gctx;
+    uint8_t *body;
+    size_t blen;
+    uint32_t num;
+    int ret;
+
+    /* get max num of entries to return in one call */
+    nss_packet_get_body(cctx->creq->in, &body, &blen);
+    if (blen != sizeof(uint32_t)) {
+        return EINVAL;
+    }
+    num = *((uint32_t *)body);
+
+    /* create response packet */
+    ret = nss_packet_new(cctx->creq, 0,
+                         nss_packet_get_cmd(cctx->creq->in),
+                         &cctx->creq->out);
+    if (ret != EOK) {
+        return ret;
+    }
+
+    if (status != LDB_SUCCESS) {
+        nss_packet_set_error(cctx->creq->out, status);
+        goto done;
+    }
+
+    gctx->grps = talloc_steal(gctx, res);
+
+    ret = nss_cmd_retgrent(cctx, num);
+    nss_packet_set_error(cctx->creq->out, ret);
+
+done:
+    nss_cmd_done(nctx);
+    return EOK;
+}
+
+static int nss_cmd_getgrent(struct cli_ctx *cctx)
+{
+    struct nss_cmd_ctx *nctx;
+    struct getent_ctx *gctx;
+    uint8_t *body;
+    size_t blen;
+    uint32_t num;
+    int ret;
+
+    /* get max num of entries to return in one call */
+    nss_packet_get_body(cctx->creq->in, &body, &blen);
+    if (blen != sizeof(uint32_t)) {
+        return EINVAL;
+    }
+    num = *((uint32_t *)body);
+
+    nctx = talloc(cctx, struct nss_cmd_ctx);
+    if (!nctx) {
+        return ENOMEM;
+    }
+    nctx->cctx = cctx;
+
+    /* see if we need to trigger an implicit setpwent() */
+    if (cctx->gctx == NULL || cctx->gctx->grps == NULL) {
+        if (cctx->gctx == NULL) {
+            gctx = talloc_zero(cctx, struct getent_ctx);
+            if (!gctx) {
+                talloc_free(nctx);
+                return ENOMEM;
+            }
+            cctx->gctx = gctx;
+        }
+        if (cctx->gctx->grps == NULL) {
+            ret = nss_ldb_enumgrent(nctx, cctx->ev, cctx->ldb,
+                                    nss_cmd_getgrent_callback, nctx);
+            return ret;
+        }
+    }
+
+    /* create response packet */
+    ret = nss_packet_new(cctx->creq, 0,
+                         nss_packet_get_cmd(cctx->creq->in),
+                         &cctx->creq->out);
+    if (ret != EOK) {
+        return ret;
+    }
+
+    ret = nss_cmd_retgrent(cctx, num);
+    nss_packet_set_error(cctx->creq->out, ret);
+    nss_cmd_done(nctx);
+    return EOK;
+}
+
+static int nss_cmd_endgrent(struct cli_ctx *cctx)
+{
+    struct nss_cmd_ctx *nctx;
+    int ret;
+
+    nctx = talloc(cctx, struct nss_cmd_ctx);
+    if (!nctx) {
+        return ENOMEM;
+    }
+    nctx->cctx = cctx;
+
+    /* create response packet */
+    ret = nss_packet_new(cctx->creq, 0,
+                         nss_packet_get_cmd(cctx->creq->in),
+                         &cctx->creq->out);
+
+    if (cctx->gctx == NULL) goto done;
+    if (cctx->gctx->grps == NULL) goto done;
+
+    /* free results and reset */
+    talloc_free(cctx->gctx->grps);
+    cctx->gctx->grps = NULL;
+    cctx->gctx->grp_cur = 0;
+
+done:
+    nss_cmd_done(nctx);
+    return EOK;
+}
+
 struct nss_cmd_table nss_cmds[] = {
     {SSS_NSS_GET_VERSION, nss_cmd_get_version},
     {SSS_NSS_GETPWNAM, nss_cmd_getpwnam},
@@ -677,6 +891,9 @@ struct nss_cmd_table nss_cmds[] = {
     {SSS_NSS_ENDPWENT, nss_cmd_endpwent},
     {SSS_NSS_GETGRNAM, nss_cmd_getgrnam},
     {SSS_NSS_GETGRGID, nss_cmd_getgrgid},
+    {SSS_NSS_SETGRENT, nss_cmd_setgrent},
+    {SSS_NSS_GETGRENT, nss_cmd_getgrent},
+    {SSS_NSS_ENDGRENT, nss_cmd_endgrent},
     {SSS_NSS_NULL, NULL}
 };
 
diff --git a/server/nss/nsssrv_ldb.c b/server/nss/nsssrv_ldb.c
index dce8d48b..62268042 100644
--- a/server/nss/nsssrv_ldb.c
+++ b/server/nss/nsssrv_ldb.c
@@ -131,6 +131,8 @@ static struct nss_ldb_search_ctx *init_sctx(TALLOC_CTX *mem_ctx,
     return sctx;
 }
 
+/* users */
+
 static int pwd_search(struct nss_ldb_search_ctx *sctx,
                      struct ldb_context *ldb,
                      const char *expression)
@@ -219,7 +221,97 @@ int nss_ldb_enumpwent(TALLOC_CTX *mem_ctx,
     return pwd_search(sctx, ldb, NSS_PWENT_FILTER);
 }
 
+/* groups */
+
+struct get_mem_ctx {
+    struct nss_ldb_search_ctx *ret_sctx;
+    struct ldb_message **grps;
+    int num_grps;
+};
+
+static int get_members(void *ptr, int status,
+                       struct ldb_result *res)
+{
+    struct nss_ldb_search_ctx *sctx;
+    struct get_mem_ctx *gmctx;
+    struct nss_ldb_search_ctx *mem_sctx;
+    static const char *attrs[] = NSS_GRPW_ATTRS;
+    struct ldb_request *req;
+    struct ldb_message *msg;
+    struct ldb_result *ret_res;
+    const char *expression;
+    int ret, i;
+
+    sctx = talloc_get_type(ptr, struct nss_ldb_search_ctx);
+    gmctx = talloc_get_type(sctx->ptr, struct get_mem_ctx);
+
+    if (status != LDB_SUCCESS) {
+        return request_error(gmctx->ret_sctx, status);
+    }
+
+    ret_res = gmctx->ret_sctx->res;
+
+    /* append previous search results to final (if any) */
+    if (res && res->count != 0) {
+        ret_res->msgs = talloc_realloc(ret_res, ret_res->msgs,
+                                       struct ldb_message *,
+                                       ret_res->count + res->count + 1);
+        for(i = 0; i < res->count; i++) {
+            ret_res->msgs[ret_res->count] = talloc_steal(ret_res, res->msgs[i]);
+            ret_res->count++;
+        }
+        ret_res->msgs[ret_res->count] = NULL;
+    }
+
+    if (gmctx->grps[0] == NULL) {
+        return request_done(gmctx->ret_sctx);
+    }
+
+    mem_sctx = init_sctx(gmctx, sctx->ldb, get_members, sctx);
+    if (!mem_sctx) {
+        return request_error(gmctx->ret_sctx, LDB_ERR_OPERATIONS_ERROR);
+    }
+
+    /* fetch next group to search for members */
+    gmctx->num_grps--;
+    msg = gmctx->grps[gmctx->num_grps];
+    gmctx->grps[gmctx->num_grps] = NULL;
+
+    /* queue the group entry on the final result structure */
+    ret_res->msgs = talloc_realloc(ret_res, ret_res->msgs,
+                                   struct ldb_message *,
+                                   ret_res->count + 2);
+    if (!ret_res->msgs) {
+        return request_error(gmctx->ret_sctx, LDB_ERR_OPERATIONS_ERROR);
+    }
+    ret_res->msgs[ret_res->count + 1] = NULL;
+    ret_res->msgs[ret_res->count] = talloc_steal(ret_res->msgs, msg);
+    ret_res->count++;
+
+    /* search for this group members */
+    expression = talloc_asprintf(mem_sctx, NSS_GRNA2_FILTER,
+                                 ldb_dn_get_linearized(msg->dn));
+    if (!expression) {
+        return request_error(gmctx->ret_sctx, LDB_ERR_OPERATIONS_ERROR);
+    }
+
+    ret = ldb_build_search_req(&req, mem_sctx->ldb, mem_sctx,
+                               ldb_dn_new(mem_sctx, mem_sctx->ldb, NSS_USER_BASE),
+                               LDB_SCOPE_SUBTREE,
+                               expression, attrs, NULL,
+                               mem_sctx, get_gen_callback,
+                               NULL);
+    if (ret != LDB_SUCCESS) {
+       return request_error(gmctx->ret_sctx, ret);
+    }
 
+    ret = ldb_request(mem_sctx->ldb, req);
+    if (ret != LDB_SUCCESS) {
+        return request_error(gmctx->ret_sctx, ret);
+    }
+
+    return LDB_SUCCESS;
+}
 
 static int get_grp_callback(struct ldb_request *req,
                             struct ldb_reply *ares)
@@ -276,35 +368,24 @@ static int get_grp_callback(struct ldb_request *req,
         if (res->count == 0) {
             return request_done(sctx);
         }
-        /* 1 result, let's search for members now and append results */
-        if (res->count == 1) {
-            static const char *attrs[] = NSS_GRPW_ATTRS;
-            struct ldb_request *ureq;
-            const char *expression;
-            int ret;
-
-            expression = talloc_asprintf(sctx, NSS_GRNA2_FILTER,
-                                         ldb_dn_get_linearized(res->msgs[0]->dn));
-            if (!expression) {
-                return request_error(sctx, LDB_ERR_OPERATIONS_ERROR);
-            }
+        if (res->count > 0) {
+            struct get_mem_ctx *gmctx;
 
-            ret = ldb_build_search_req(&ureq, sctx->ldb, sctx,
-                                       ldb_dn_new(sctx, sctx->ldb, NSS_USER_BASE),
-                                       LDB_SCOPE_SUBTREE,
-                                       expression, attrs, NULL,
-                                       sctx, get_gen_callback,
-                                       NULL);
-            if (ret != LDB_SUCCESS) {
-                return request_error(sctx, ret);
+            gmctx = talloc_zero(req, struct get_mem_ctx);
+            if (!gmctx) {
+                request_error(sctx, LDB_ERR_OPERATIONS_ERROR);
             }
+            gmctx->ret_sctx = sctx;
+            gmctx->grps = talloc_steal(gmctx, res->msgs);
+            gmctx->num_grps = res->count;
+            res->msgs = NULL;
+            res->count = 0;
 
-            ret = ldb_request(sctx->ldb, ureq);
-            if (ret != LDB_SUCCESS) {
-                return request_error(sctx, ret);
-            }
+            /* re-use sctx to create a fake handler for the first call to
+             * get_members() */
+            sctx = init_sctx(gmctx, sctx->ldb, get_members, gmctx);
 
-            return LDB_SUCCESS;
+            return get_members(sctx, LDB_SUCCESS, NULL);
         }
 
         /* anything else is an error */
@@ -388,6 +469,20 @@ int nss_ldb_getgrgid(TALLOC_CTX *mem_ctx,
     return grp_search(sctx, ldb, expression);
 }
 
+int nss_ldb_enumgrent(TALLOC_CTX *mem_ctx,
+                      struct event_context *ev,
+                      struct ldb_context *ldb,
+                      nss_ldb_callback_t fn, void *ptr)
+{
+    struct nss_ldb_search_ctx *sctx;
+
+    sctx = init_sctx(mem_ctx, ldb, fn, ptr);
+    if (!sctx) {
+        return ENOMEM;
+    }
+
+    return grp_search(sctx, ldb, NSS_GRENT_FILTER);
+}
 
 int nss_ldb_init(TALLOC_CTX *mem_ctx,
                  struct event_context *ev,
diff --git a/server/nss/nsssrv_ldb.h b/server/nss/nsssrv_ldb.h
index ebb97255..8cc7ebca 100644
--- a/server/nss/nsssrv_ldb.h
+++ b/server/nss/nsssrv_ldb.h
@@ -6,7 +6,7 @@
 #define NSS_PW_HOMEDIR "HomeDirectory"
 #define NSS_PW_SHELL "loginShell"
 
-#define NSS_GR_NAME "gid"
+#define NSS_GR_NAME "cn"
 #define NSS_GR_GIDNUM "gidNumber"
 #define NSS_GR_MEMBER "member"
 
@@ -45,3 +45,8 @@ int nss_ldb_getgrgid(TALLOC_CTX *mem_ctx,
                      uint64_t gid,
                      nss_ldb_callback_t fn, void *ptr);
 
+int nss_ldb_enumgrent(TALLOC_CTX *mem_ctx,
+                      struct event_context *ev,
+                      struct ldb_context *ldb,
+                      nss_ldb_callback_t fn, void *ptr);
+