diff options
Diffstat (limited to 'loginutils/addgroup.c')
| -rw-r--r-- | loginutils/addgroup.c | 183 |
1 files changed, 183 insertions, 0 deletions
diff --git a/loginutils/addgroup.c b/loginutils/addgroup.c new file mode 100644 index 0000000..89414d7 --- /dev/null +++ b/loginutils/addgroup.c @@ -0,0 +1,183 @@ +/* vi: set sw=4 ts=4: */ +/* + * addgroup - add groups to /etc/group and /etc/gshadow + * + * Copyright (C) 1999 by Lineo, inc. and John Beppu + * Copyright (C) 1999,2000,2001 by John Beppu <beppu@codepoet.org> + * Copyright (C) 2007 by Tito Ragusa <farmatito@tiscali.it> + * + * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. + * + */ + +#include "libbb.h" + +static void xgroup_study(struct group *g) +{ + /* Make sure gr_name is unused */ + if (getgrnam(g->gr_name)) { + goto error; + } + + /* Check if the desired gid is free + * or find the first free one */ + while (1) { + if (!getgrgid(g->gr_gid)) { + return; /* found free group: return */ + } + if (option_mask32) { + /* -g N, cannot pick gid other than N: error */ + g->gr_name = itoa(g->gr_gid); + goto error; + } + g->gr_gid++; + if (g->gr_gid <= 0) { + /* overflowed: error */ + bb_error_msg_and_die("no gids left"); + } + } + + error: + /* exit */ + bb_error_msg_and_die("group %s already exists", g->gr_name); +} + +/* append a new user to the passwd file */ +static void new_group(char *group, gid_t gid) +{ + FILE *file; + struct group gr; + + /* make sure gid and group haven't already been allocated */ + gr.gr_gid = gid; + gr.gr_name = group; + xgroup_study(&gr); + + /* add entry to group */ + file = xfopen(bb_path_group_file, "a"); + /* group:passwd:gid:userlist */ + fprintf(file, "%s:x:%u:\n", group, (unsigned)gr.gr_gid); + if (ENABLE_FEATURE_CLEAN_UP) + fclose(file); +#if ENABLE_FEATURE_SHADOWPASSWDS + file = fopen_or_warn(bb_path_gshadow_file, "a"); + if (file) { + fprintf(file, "%s:!::\n", group); + if (ENABLE_FEATURE_CLEAN_UP) + fclose(file); + } +#endif +} + +#if ENABLE_FEATURE_ADDUSER_TO_GROUP +static void add_user_to_group(char **args, + const char *path, + FILE* FAST_FUNC (*fopen_func)(const char *fileName, const char *mode)) +{ + char *line; + int len = strlen(args[1]); + llist_t *plist = NULL; + FILE *group_file; + + group_file = fopen_func(path, "r"); + + if (!group_file) return; + + while ((line = xmalloc_fgetline(group_file)) != NULL) { + /* Find the group */ + if (!strncmp(line, args[1], len) + && line[len] == ':' + ) { + /* Add the new user */ + line = xasprintf("%s%s%s", line, + last_char_is(line, ':') ? "" : ",", + args[0]); + } + llist_add_to_end(&plist, line); + } + + if (ENABLE_FEATURE_CLEAN_UP) { + fclose(group_file); + group_file = fopen_func(path, "w"); + while ((line = llist_pop(&plist))) { + if (group_file) + fprintf(group_file, "%s\n", line); + free(line); + } + if (group_file) + fclose(group_file); + } else { + group_file = fopen_func(path, "w"); + if (group_file) + while ((line = llist_pop(&plist))) + fprintf(group_file, "%s\n", line); + } +} +#endif + +/* + * addgroup will take a login_name as its first parameter. + * + * gid can be customized via command-line parameters. + * If called with two non-option arguments, addgroup + * will add an existing user to an existing group. + */ +int addgroup_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; +int addgroup_main(int argc UNUSED_PARAM, char **argv) +{ + char *group; + gid_t gid = 0; + + /* need to be root */ + if (geteuid()) { + bb_error_msg_and_die(bb_msg_perm_denied_are_you_root); + } + + /* Syntax: + * addgroup group + * addgroup -g num group + * addgroup user group + * Check for min, max and missing args */ + opt_complementary = "-1:?2"; + if (getopt32(argv, "g:", &group)) { + gid = xatoul_range(group, 0, ((unsigned long)(gid_t)ULONG_MAX) >> 1); + } + /* move past the commandline options */ + argv += optind; + //argc -= optind; + +#if ENABLE_FEATURE_ADDUSER_TO_GROUP + if (argv[1]) { + struct group *gr; + + if (option_mask32) { + /* -g was there, but "addgroup -g num user group" + * is a no-no */ + bb_show_usage(); + } + + /* check if group and user exist */ + xuname2uid(argv[0]); /* unknown user: exit */ + xgroup2gid(argv[1]); /* unknown group: exit */ + /* check if user is already in this group */ + gr = getgrnam(argv[1]); + for (; *(gr->gr_mem) != NULL; (gr->gr_mem)++) { + if (!strcmp(argv[0], *(gr->gr_mem))) { + /* user is already in group: do nothing */ + return EXIT_SUCCESS; + } + } + add_user_to_group(argv, bb_path_group_file, xfopen); +#if ENABLE_FEATURE_SHADOWPASSWDS + add_user_to_group(argv, bb_path_gshadow_file, fopen_or_warn); +#endif + } else +#endif /* ENABLE_FEATURE_ADDUSER_TO_GROUP */ + { + die_if_bad_username(argv[0]); + new_group(argv[0], gid); + + } + /* Reached only on success */ + return EXIT_SUCCESS; +} |