Imported Upstream version 1.8.5

[debian/sudo] / plugins / system_group / system_group.c

diff --git a/plugins/system_group/system_group.c b/plugins/system_group/system_group.c
new file mode 100644 (file)
index 0000000..f4343f0
--- /dev/null
+++ b/plugins/system_group/system_group.c
@@ -0,0 +1,171 @@
+/*
+ * Copyright (c) 2010, 2012 Todd C. Miller <Todd.Miller@courtesan.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <config.h>
+
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/stat.h>
+
+#include <stdio.h>
+#ifdef STDC_HEADERS
+# include <stdlib.h>
+# include <stddef.h>
+#else
+# ifdef HAVE_STDLIB_H
+#  include <stdlib.h>
+# endif
+#endif /* STDC_HEADERS */
+#ifdef HAVE_STDBOOL_H
+# include <stdbool.h>
+#else
+# include "compat/stdbool.h"
+#endif /* HAVE_STDBOOL_H */
+#ifdef HAVE_STRING_H
+# if defined(HAVE_MEMORY_H) && !defined(STDC_HEADERS)
+#  include <memory.h>
+# endif
+# include <string.h>
+#endif /* HAVE_STRING_H */
+#ifdef HAVE_STRINGS_H
+# include <strings.h>
+#endif /* HAVE_STRINGS_H */
+#ifdef HAVE_UNISTD_H
+# include <unistd.h>
+#endif /* HAVE_UNISTD_H */
+#ifdef HAVE_DLOPEN
+# include <dlfcn.h>
+#else
+# include "compat/dlfcn.h"
+#endif
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <grp.h>
+#include <pwd.h>
+
+#include "sudo_plugin.h"
+#include "missing.h"
+
+#ifndef RTLD_DEFAULT
+# define RTLD_DEFAULT  NULL
+#endif
+
+/*
+ * Sudoers group plugin that does group name-based lookups using the system
+ * group database functions, similar to how sudo behaved prior to 1.7.3.
+ * This can be used on systems where lookups by group ID are problematic.
+ */
+
+static sudo_printf_t sudo_log;
+
+typedef struct group * (*sysgroup_getgrnam_t)(const char *);
+typedef struct group * (*sysgroup_getgrgid_t)(gid_t);
+typedef void (*sysgroup_gr_delref_t)(struct group *);
+
+static sysgroup_getgrnam_t sysgroup_getgrnam;
+static sysgroup_getgrgid_t sysgroup_getgrgid;
+static sysgroup_gr_delref_t sysgroup_gr_delref;
+static bool need_setent;
+
+static int
+sysgroup_init(int version, sudo_printf_t sudo_printf, char *const argv[])
+{
+    void *handle;
+
+    sudo_log = sudo_printf;
+
+    if (GROUP_API_VERSION_GET_MAJOR(version) != GROUP_API_VERSION_MAJOR) {
+       sudo_log(SUDO_CONV_ERROR_MSG,
+           "sysgroup_group: incompatible major version %d, expected %d\n",
+           GROUP_API_VERSION_GET_MAJOR(version),
+           GROUP_API_VERSION_MAJOR);
+       return -1;
+    }
+
+    /* Share group cache with sudo if possible. */
+    handle = dlsym(RTLD_DEFAULT, "sudo_getgrnam");
+    if (handle != NULL) {
+       sysgroup_getgrnam = (sysgroup_getgrnam_t)handle;
+    } else {
+       sysgroup_getgrnam = (sysgroup_getgrnam_t)getgrnam;
+       need_setent = true;
+    }
+
+    handle = dlsym(RTLD_DEFAULT, "sudo_getgrgid");
+    if (handle != NULL) {
+       sysgroup_getgrgid = (sysgroup_getgrgid_t)handle;
+    } else {
+       sysgroup_getgrgid = (sysgroup_getgrgid_t)getgrgid;
+       need_setent = true;
+    }
+
+    handle = dlsym(RTLD_DEFAULT, "gr_delref");
+    if (handle != NULL)
+       sysgroup_gr_delref = (sysgroup_gr_delref_t)handle;
+
+    if (need_setent)
+       setgrent();
+
+    return true;
+}
+
+static void
+sysgroup_cleanup(void)
+{
+    if (need_setent)
+       endgrent();
+}
+
+/*
+ * Returns true if "user" is a member of "group", else false.
+ */
+static int
+sysgroup_query(const char *user, const char *group, const struct passwd *pwd)
+{
+    char **member, *ep = '\0';
+    struct group *grp;
+
+    grp = sysgroup_getgrnam(group);
+    if (grp == NULL && group[0] == '#' && group[1] != '\0') {
+       long lval = strtol(group + 1, &ep, 10);
+       if (*ep == '\0') {
+           if ((lval != LONG_MAX && lval != LONG_MIN) || errno != ERANGE)
+               grp = sysgroup_getgrgid((gid_t)lval);
+       }
+    }
+    if (grp != NULL) {
+       for (member = grp->gr_mem; *member != NULL; member++) {
+           if (strcasecmp(user, *member) == 0) {
+               if (sysgroup_gr_delref)
+                   sysgroup_gr_delref(grp);
+               return true;
+           }
+       }
+       if (sysgroup_gr_delref)
+           sysgroup_gr_delref(grp);
+    }
+
+    return false;
+}
+
+struct sudoers_group_plugin group_plugin = {
+    GROUP_API_VERSION,
+    sysgroup_init,
+    sysgroup_cleanup,
+    sysgroup_query
+};