/* -*-c-*-
- *
- * $Id: util.c,v 1.3 2004/04/08 01:36:17 mdw Exp $
*
* Utilities for the client and the server
*
#include <stdlib.h>
#include <string.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include <pwd.h>
+#include <grp.h>
+
#include <mLib/dstr.h>
+#include <mLib/report.h>
#include "util.h"
}
}
+/* --- @u_getuser@ --- *
+ *
+ * Arguments: @const char *name@ = user name or id requested
+ * @gid_t *gg@ = where to store corresponding gid
+ *
+ * Returns: Corresponding uid.
+ *
+ * Use: Resolves a user name into a uid. Dies on failure; suitable
+ * for use in argument parsing.
+ */
+
+uid_t u_getuser(const char *name, gid_t *gg)
+{
+ struct passwd *pw;
+ char *p;
+ unsigned long i = strtoul(name, &p, 0);
+
+ if (!*p)
+ pw = getpwuid(i);
+ else
+ pw = getpwnam(name);
+ if (!pw)
+ die(EXIT_FAILURE, "user `%s' not found", name);
+ if (gg && *gg == -1)
+ *gg = pw->pw_gid;
+ return (pw->pw_uid);
+}
+
+/* --- @u_getgroup@ --- *
+ *
+ * Arguments: @const char *name@ = user name or id requested
+ *
+ * Returns: Corresponding gid.
+ *
+ * Use: Resolves a group name into a gid. Dies on failure; suitable
+ * for use in argument parsing.
+ */
+
+gid_t u_getgroup(const char *name)
+{
+ struct group *gr;
+ char *p;
+ unsigned long i = strtoul(name, &p, 0);
+
+ if (!*p)
+ gr = getgrgid(i);
+ else
+ gr = getgrnam(name);
+ if (!gr)
+ die(EXIT_FAILURE, "group `%s' not found", name);
+ return (gr->gr_gid);
+}
+
+/* --- @u_setugid@ --- *
+ *
+ * Arguments: @uid_t u@ = user to set
+ * @gid_t g@ = group to set
+ *
+ * Returns: ---
+ *
+ * Use: Sets user and group to the given values; aborts on failure.
+ */
+
+void u_setugid(uid_t u, gid_t g)
+{
+ if (g != (gid_t)-1) {
+ if (setgid(g) || (getuid() == 0 && setgroups(1, &g))) {
+ die(EXIT_FAILURE, "couldn't setgid to %u: %s",
+ (unsigned)g, strerror(errno));
+ }
+ }
+ if (u != (uid_t)-1) {
+ if (setuid(u)) {
+ die(EXIT_FAILURE, "couldn't setuid to %u: %s",
+ (unsigned)u, strerror(errno));
+ }
+ }
+}
+
/*----- That's all, folks -------------------------------------------------*/