3:37 p.m.
This patch updates virGetUserID and virGetGroupID to be able to parse a
user or group name in a similar way to coreutils' chown. This means that
a numeric value with a leading plus sign is always parsed as an ID,
otherwise the functions try to parse the input first as a user or group
name and if this fails they try to parse it as an ID.
This patch includes Peter Krempa's changes to correctly handle errors
returned by getpwnam_r and getgrnam_r.
---
src/util/util.c | 143 ++++++++++++++++++++++++++++++++++++++++----------------
1 file changed, 104 insertions(+), 39 deletions(-)
diff --git a/src/util/util.c b/src/util/util.c
index 43fdaf1..348c388 100644
--- a/src/util/util.c
+++ b/src/util/util.c
@@ -2495,16 +2495,19 @@ char *virGetGroupName(gid_t gid)
return virGetGroupEnt(gid);
}
-
-int virGetUserID(const char *name,
- uid_t *uid)
+/* Search in the password database for a user id that matches the user name
+ * `name`. Returns 0 on success, -1 on failure or 1 if name cannot be found.
+ */
+static int
+virGetUserIDByName(const char *name, uid_t *uid)
{
- char *strbuf;
+ char *strbuf = NULL;
struct passwd pwbuf;
struct passwd *pw = NULL;
long val = sysconf(_SC_GETPW_R_SIZE_MAX);
size_t strbuflen = val;
int rc;
+ int ret = -1;
/* sysconf is a hint; if it fails, fall back to a reasonable size */
if (val < 0)
@@ -2512,48 +2515,81 @@ int virGetUserID(const char *name,
if (VIR_ALLOC_N(strbuf, strbuflen) < 0) {
virReportOOMError();
- return -1;
+ goto cleanup;
}
- /*
- * From the manpage (terrifying but true):
- *
- * ERRORS
- * 0 or ENOENT or ESRCH or EBADF or EPERM or ...
- * The given name or uid was not found.
- */
while ((rc = getpwnam_r(name, &pwbuf, strbuf, strbuflen, &pw)) == ERANGE) {
if (VIR_RESIZE_N(strbuf, strbuflen, strbuflen, strbuflen) < 0) {
virReportOOMError();
- VIR_FREE(strbuf);
- return -1;
+ goto cleanup;
}
}
- if (rc != 0 || pw == NULL) {
- virReportSystemError(rc,
- _("Failed to find user record for name
'%s'"),
+
+ if (rc != 0) {
+ virReportSystemError(rc, _("Failed to get user record for name
'%s'"),
name);
- VIR_FREE(strbuf);
- return -1;
+ goto cleanup;
+ }
+
+ if (!pw) {
+ VIR_DEBUG("User record for user '%s' does not exist", name);
+ ret = 1;
+ goto cleanup;
}
*uid = pw->pw_uid;
+ ret = 0;
+cleanup:
VIR_FREE(strbuf);
+ return ret;
+}
+
+/* Try to match a user id based on `user`. The default behavior is to parse
+ * `user` first as a user name and then as a user id. However if `user`
+ * contains a leading '+', the rest of the string is always parsed as a uid.
+ *
+ * Returns 0 on success and -1 otherwise.
+ */
+int
+virGetUserID(const char *user, uid_t *uid)
+{
+ unsigned int uint_uid;
+
+ if (*user == '+') {
+ user++;
+ } else {
+ int rc = virGetUserIDByName(user, uid);
+ if (rc <= 0)
+ return rc;
+ }
+
+ if (virStrToLong_ui(user, NULL, 10, &uint_uid) < 0 ||
+ ((uid_t) uint_uid) != uint_uid) {
+ virReportError(VIR_ERR_INVALID_ARG, _("Failed to parse user
'%s'"),
+ user);
+ return -1;
+ }
+
+ *uid = uint_uid;
+
return 0;
}
-
-int virGetGroupID(const char *name,
- gid_t *gid)
+/* Search in the group database for a group id that matches the group name
+ * `name`. Returns 0 on success, -1 on failure or 1 if name cannot be found.
+ */
+static int
+virGetGroupIDByName(const char *name, gid_t *gid)
{
- char *strbuf;
+ char *strbuf = NULL;
struct group grbuf;
struct group *gr = NULL;
long val = sysconf(_SC_GETGR_R_SIZE_MAX);
size_t strbuflen = val;
int rc;
+ int ret = -1;
/* sysconf is a hint; if it fails, fall back to a reasonable size */
if (val < 0)
@@ -2561,39 +2597,68 @@ int virGetGroupID(const char *name,
if (VIR_ALLOC_N(strbuf, strbuflen) < 0) {
virReportOOMError();
- return -1;
+ goto cleanup;
}
- /*
- * From the manpage (terrifying but true):
- *
- * ERRORS
- * 0 or ENOENT or ESRCH or EBADF or EPERM or ...
- * The given name or uid was not found.
- */
while ((rc = getgrnam_r(name, &grbuf, strbuf, strbuflen, &gr)) == ERANGE) {
if (VIR_RESIZE_N(strbuf, strbuflen, strbuflen, strbuflen) < 0) {
virReportOOMError();
- VIR_FREE(strbuf);
- return -1;
+ goto cleanup;
}
}
- if (rc != 0 || gr == NULL) {
- virReportSystemError(rc,
- _("Failed to find group record for name
'%s'"),
+
+ if (rc != 0) {
+ virReportSystemError(rc, _("Failed to get group record for name
'%s'"),
name);
- VIR_FREE(strbuf);
- return -1;
+ goto cleanup;
+ }
+
+ if (!gr) {
+ VIR_DEBUG("Group record for group '%s' does not exist", name);
+ ret = 1;
+ goto cleanup;
}
*gid = gr->gr_gid;
+ ret = 0;
+cleanup:
VIR_FREE(strbuf);
+ return ret;
+}
+
+/* Try to match a group id based on `group`. The default behavior is to parse
+ * `group` first as a group name and then as a group id. However if `group`
+ * contains a leading '+', the rest of the string is always parsed as a guid.
+ *
+ * Returns 0 on success and -1 otherwise.
+ */
+int
+virGetGroupID(const char *group, gid_t *gid)
+{
+ unsigned int uint_gid;
+
+ if (*group == '+') {
+ group++;
+ } else {
+ int rc = virGetGroupIDByName(group, gid);
+ if (rc <= 0)
+ return rc;
+ }
+
+ if (virStrToLong_ui(group, NULL, 10, &uint_gid) < 0 ||
+ ((gid_t) uint_gid) != uint_gid) {
+ virReportError(VIR_ERR_INVALID_ARG, _("Failed to parse group
'%s'"),
+ group);
+ return -1;
+ }
+
+ *gid = uint_gid;
+
return 0;
}
-
/* Set the real and effective uid and gid to the given values, and call
* initgroups so that the process has all the assumed group membership of
* that uid. return 0 on success, -1 on failure (the original system error
--
1.7.12