Implementation of client side Static translation method in libnfsidmap.
Since the [Static] section in idmapd.conf does not distinguish between
user and group mappings we try both cases for each defined mapping. The
code caches id->name mappings in the init function.
diff --git a/static.c b/static.c
index fffd458..8be87e8 100644
--- a/static.c
+++ b/static.c
@@ -40,6 +40,7 @@
#include <grp.h>
#include <errno.h>
+#include "queue.h"
#include "cfg.h"
#include "nfsidmap.h"
#include "nfsidmap_internal.h"
@@ -57,6 +58,40 @@ struct pwbuf {
char buf[1];
};
+struct grbuf {
+ struct group grbuf;
+ char buf[1];
+};
+
+struct uid_mapping {
+ LIST_ENTRY (uid_mapping) link;
+ uid_t uid;
+ char * principal;
+ char * localname;
+};
+
+struct gid_mapping {
+ LIST_ENTRY (gid_mapping) link;
+ gid_t gid;
+ char * principal;
+ char * localgroup;
+};
+
+static __inline__ u_int8_t uid_hash (uid_t uid)
+{
+ return uid % 256;
+}
+
+static __inline__ u_int8_t gid_hash (gid_t gid)
+{
+ return gid % 256;
+}
+
+//Hash tables of uid and guids to principals mappings.
+//We reuse some queue/hash functions from cfg.c.
+LIST_HEAD (uid_mappings, uid_mapping) uid_mappings[256];
+LIST_HEAD (gid_mappings, gid_mapping) gid_mappings[256];
+
static struct passwd *static_getpwnam(const char *name, const char *domain,
int *err_p)
{
@@ -75,12 +110,9 @@ static struct passwd *static_getpwnam(const char *name, const char *domain,
localname = conf_get_str("Static", (char *)name);
if (!localname) {
err = ENOENT;
- goto err;
+ goto err_free_buf;
}
- IDMAP_LOG(4, ("static_getpwnam: name '%s' mapped to '%s'\n",
- name, localname));
-
again:
err = getpwnam_r(localname, &buf->pwbuf, buf->buf, buflen, &pw);
@@ -91,12 +123,15 @@ again:
if (err == 0)
err = ENOENT;
- IDMAP_LOG(0, ("static_getpwnam: name '%s' not found\n",
- localname));
+ IDMAP_LOG(0, ("static_getpwnam: localname '%s' for '%s' not found\n",
+ localname, name));
goto err_free_buf;
}
+ IDMAP_LOG(4, ("static_getpwnam: name '%s' mapped to '%s'\n",
+ name, localname));
+
*err_p = 0;
return pw;
@@ -107,6 +142,56 @@ err:
return NULL;
}
+static struct group *static_getgrnam(const char *name, const char *domain,
+ int *err_p)
+{
+ struct group *gr;
+ struct grbuf *buf;
+ size_t buflen = sysconf(_SC_GETGR_R_SIZE_MAX);
+ char *localgroup;
+ int err;
+
+ buf = malloc(sizeof(*buf) + buflen);
+ if (!buf) {
+ err = ENOMEM;
+ goto err;
+ }
+
+ localgroup = conf_get_str("Static", (char *)name);
+ if (!localgroup) {
+ err = ENOENT;
+ goto err_free_buf;
+ }
+
+again:
+ err = getgrnam_r(localgroup, &buf->grbuf, buf->buf, buflen, &gr);
+
+ if (err == EINTR)
+ goto again;
+
+ if (!gr) {
+ if (err == 0)
+ err = ENOENT;
+
+ IDMAP_LOG(0, ("static_getgrnam: local group '%s' for '%s' not found\n",
+ localgroup, name));
+
+ goto err_free_buf;
+ }
+
+ IDMAP_LOG(4, ("static_getgrnam: group '%s' mapped to '%s'\n",
+ name, localgroup));
+
+ *err_p = 0;
+ return gr;
+
+err_free_buf:
+ free(buf);
+err:
+ *err_p = err;
+ return NULL;
+}
+
static int static_gss_princ_to_ids(char *secname, char *princ,
uid_t *uid, uid_t *gid,
extra_mapping_params **ex)
@@ -151,14 +236,173 @@ static int static_gss_princ_to_grouplist(char *secname, char *princ,
return -err;
}
+static int static_name_to_uid(char *name, uid_t *uid)
+{
+ struct passwd *pw;
+ int err;
+
+ pw = static_getpwnam(name, NULL, &err);
+
+ if (pw) {
+ *uid = pw->pw_uid;
+ free(pw);
+ }
+
+ return -err;
+}
+
+static int static_name_to_gid(char *name, gid_t *gid)
+{
+ struct group *gr;
+ int err;
+
+ gr = static_getgrnam(name, NULL, &err);
+
+ if (gr) {
+ *gid = gr->gr_gid;
+ free(gr);
+ }
+
+ return -err;
+}
+
+static int static_uid_to_name(uid_t uid, char *domain, char *name, size_t len)
+{
+ struct passwd *pw;
+ struct uid_mapping * um;
+
+ for (um = LIST_FIRST (&uid_mappings[uid_hash (uid)]); um;
+ um = LIST_NEXT (um, link)) {
+ if (um->uid == uid) {
+ strcpy(name, um->principal);
+ return 0;
+ }
+ }
+
+ return -ENOENT;
+}
+
+static int static_gid_to_name(gid_t gid, char *domain, char *name, size_t len)
+{
+ struct group *gr;
+ struct gid_mapping * gm;
+
+ for (gm = LIST_FIRST (&gid_mappings[gid_hash (gid)]); gm;
+ gm = LIST_NEXT (gm, link)) {
+ if (gm->gid == gid) {
+ strcpy(name, gm->principal);
+ return 0;
+ }
+ }
+
+ return -ENOENT;
+}
+
+/*
+ * We buffer all UID's for which static mappings is defined in advance, so the
+ * uid_to_name functions will be fast enough.
+ */
+
+static int static_init() {
+ int err;
+ uid_t uid;
+ struct conf_list * princ_list = NULL;
+ struct conf_list_node * cln, *next;
+ struct uid_mapping * unode;
+ struct gid_mapping * gnode;
+ struct passwd * pw = NULL;
+ struct group * gr = NULL;
+ unsigned int i;
+
+ //init hash_table first
+ for (i = 0; i < sizeof uid_mappings / sizeof uid_mappings[0]; i++)
+ LIST_INIT (&uid_mappings[i]);
+
+ //get all principals for which we have mappings
+ princ_list = conf_get_tag_list("Static");
+
+ if (!princ_list) {
+ return -ENOENT;
+ }
+
+ /* As we can not distinguish between mappings for users and groups, we try to
+ * resolve all mappings for both cases.
+ */
+
+ //resolve uid of localname account for all such principals and cache it
+ for (cln = TAILQ_FIRST (&princ_list->fields); cln; cln = next)
+ {
+ next = TAILQ_NEXT (cln, link);
+
+ pw = static_getpwnam(cln->field, NULL, &err);
+ if (!pw) {
+ continue;
+ }
+
+ unode = calloc (1, sizeof *unode);
+ if (!unode)
+ {
+ warnx("static_init: calloc (1, %lu) failed",
+ (unsigned long)sizeof *unode);
+ free(pw);
+ return -ENOMEM;
+ }
+ unode->uid = pw->pw_uid;
+ unode->principal = strdup(cln->field);
+
+ unode->localname = conf_get_str("Static", cln->field);
+ if (!unode->localname) {
+ free(pw);
+ return -ENOENT;
+ }
+
+ free(pw);
+
+ LIST_INSERT_HEAD (&uid_mappings[uid_hash(unode->uid)], unode, link);
+ }
+
+ //resolve gid of localgroup accounts and cache it
+ for (cln = TAILQ_FIRST (&princ_list->fields); cln; cln = next)
+ {
+ next = TAILQ_NEXT (cln, link);
+
+ gr = static_getgrnam(cln->field, NULL, &err);
+ if (!pw) {
+ continue;
+ }
+
+ gnode = calloc (1, sizeof *gnode);
+ if (!gnode)
+ {
+ warnx("static_init: calloc (1, %lu) failed",
+ (unsigned long)sizeof *gnode);
+ free(pw);
+ return -ENOMEM;
+ }
+ gnode->gid = pw->pw_uid;
+ gnode->principal = strdup(cln->field);
+
+ gnode->localgroup = conf_get_str("Static", cln->field);
+ if (!gnode->localgroup) {
+ free(pw);
+ return -ENOENT;
+ }
+
+ free(pw);
+
+ LIST_INSERT_HEAD (&gid_mappings[gid_hash(gnode->gid)], gnode, link);
+ }
+ return 0;
+}
+
struct trans_func static_trans = {
.name = "static",
- .init = NULL,
- .name_to_uid = NULL,
- .name_to_gid = NULL,
- .uid_to_name = NULL,
- .gid_to_name = NULL,
+ .init = static_init,
+ .name_to_uid = static_name_to_uid,
+ .name_to_gid = static_name_to_gid,
+ .uid_to_name = static_uid_to_name,
+ .gid_to_name = static_gid_to_name,
.princ_to_ids = static_gss_princ_to_ids,
.gss_princ_to_grouplist = static_gss_princ_to_grouplist,
};
