summaryrefslogtreecommitdiff
path: root/i/pc104/initrd/conf/busybox/loginutils/passwd.c
diff options
context:
space:
mode:
Diffstat (limited to 'i/pc104/initrd/conf/busybox/loginutils/passwd.c')
-rw-r--r--i/pc104/initrd/conf/busybox/loginutils/passwd.c347
1 files changed, 347 insertions, 0 deletions
diff --git a/i/pc104/initrd/conf/busybox/loginutils/passwd.c b/i/pc104/initrd/conf/busybox/loginutils/passwd.c
new file mode 100644
index 0000000..b937ce4
--- /dev/null
+++ b/i/pc104/initrd/conf/busybox/loginutils/passwd.c
@@ -0,0 +1,347 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ */
+
+#include "busybox.h"
+#include <syslog.h>
+
+
+static void nuke_str(char *str)
+{
+ if (str) memset(str, 0, strlen(str));
+}
+
+
+static int i64c(int i)
+{
+ i &= 0x3f;
+ if (i == 0)
+ return '.';
+ if (i == 1)
+ return '/';
+ if (i < 12)
+ return ('0' - 2 + i);
+ if (i < 38)
+ return ('A' - 12 + i);
+ return ('a' - 38 + i);
+}
+
+
+static void crypt_make_salt(char *p, int cnt)
+{
+ unsigned x = x; /* it's pointless to initialize it anyway :) */
+
+ x += getpid() + time(NULL) + clock();
+ do {
+ /* x = (x*1664525 + 1013904223) % 2^32 generator is lame
+ * (low-order bit is not "random", etc...),
+ * but for our purposes it is good enough */
+ x = x*1664525 + 1013904223;
+ /* BTW, Park and Miller's "minimal standard generator" is
+ * x = x*16807 % ((2^31)-1)
+ * It has no problem with visibly alternating lowest bit
+ * but is also weak in cryptographic sense + needs div,
+ * which needs more code (and slower) on many CPUs */
+ *p++ = i64c(x >> 16);
+ *p++ = i64c(x >> 22);
+ } while (--cnt);
+ *p = '\0';
+}
+
+
+static char* new_password(const struct passwd *pw, uid_t myuid, int algo)
+{
+ char salt[sizeof("$N$XXXXXXXX")]; /* "$N$XXXXXXXX" or "XX" */
+ char *orig = (char*)"";
+ char *newp = NULL;
+ char *cipher = NULL;
+ char *cp = NULL;
+ char *ret = NULL; /* failure so far */
+
+ if (myuid && pw->pw_passwd[0]) {
+ orig = bb_askpass(0, "Old password:"); /* returns ptr to static */
+ if (!orig)
+ goto err_ret;
+ cipher = pw_encrypt(orig, pw->pw_passwd); /* returns ptr to static */
+ if (strcmp(cipher, pw->pw_passwd) != 0) {
+ syslog(LOG_WARNING, "incorrect password for '%s'",
+ pw->pw_name);
+ bb_do_delay(FAIL_DELAY);
+ puts("Incorrect password");
+ goto err_ret;
+ }
+ }
+ orig = xstrdup(orig); /* or else bb_askpass() will destroy it */
+ newp = bb_askpass(0, "New password:"); /* returns ptr to static */
+ if (!newp)
+ goto err_ret;
+ newp = xstrdup(newp); /* we are going to bb_askpass() again, so save it */
+ if (ENABLE_FEATURE_PASSWD_WEAK_CHECK
+ && obscure(orig, newp, pw) && myuid)
+ goto err_ret; /* non-root is not allowed to have weak passwd */
+
+ cp = bb_askpass(0, "Retype password:");
+ if (!cp)
+ goto err_ret;
+ if (strcmp(cp, newp)) {
+ puts("Passwords don't match");
+ goto err_ret;
+ }
+
+ /*memset(salt, 0, sizeof(salt)); - why?*/
+ crypt_make_salt(salt, 1); /* des */
+ if (algo) { /* MD5 */
+ strcpy(salt, "$1$");
+ crypt_make_salt(salt + 3, 4);
+ }
+ ret = xstrdup(pw_encrypt(newp, salt)); /* returns ptr to static */
+ /* whee, success! */
+
+ err_ret:
+ nuke_str(orig);
+ if (ENABLE_FEATURE_CLEAN_UP) free(orig);
+ nuke_str(newp);
+ if (ENABLE_FEATURE_CLEAN_UP) free(newp);
+ nuke_str(cipher);
+ nuke_str(cp);
+ return ret;
+}
+
+
+#if 0
+static int get_algo(char *a)
+{
+ /* standard: MD5 */
+ int x = 1;
+ if (strcasecmp(a, "des") == 0)
+ x = 0;
+ return x;
+}
+#endif
+
+
+static int update_passwd(const char *filename, const char *username,
+ const char *new_pw)
+{
+ struct stat sb;
+ struct flock lock;
+ FILE *old_fp;
+ FILE *new_fp;
+ char *new_name;
+ char *last_char;
+ unsigned user_len;
+ int old_fd;
+ int new_fd;
+ int i;
+ int ret = 1; /* failure */
+
+ logmode = LOGMODE_STDIO;
+ /* New passwd file, "/etc/passwd+" for now */
+ new_name = xasprintf("%s+", filename);
+ last_char = &new_name[strlen(new_name)-1];
+ username = xasprintf("%s:", username);
+ user_len = strlen(username);
+
+ old_fp = fopen(filename, "r+");
+ if (!old_fp)
+ goto free_mem;
+ old_fd = fileno(old_fp);
+
+ /* Try to create "/etc/passwd+". Wait if it exists. */
+ i = 30;
+ do {
+ // FIXME: on last iteration try w/o O_EXCL but with O_TRUNC?
+ new_fd = open(new_name, O_WRONLY|O_CREAT|O_EXCL,0600);
+ if (new_fd >= 0) goto created;
+ if (errno != EEXIST) break;
+ usleep(100000); /* 0.1 sec */
+ } while (--i);
+ bb_perror_msg("cannot create '%s'", new_name);
+ goto close_old_fp;
+ created:
+ if (!fstat(old_fd, &sb)) {
+ fchmod(new_fd, sb.st_mode & 0777); /* ignore errors */
+ fchown(new_fd, sb.st_uid, sb.st_gid);
+ }
+ new_fp = fdopen(new_fd, "w");
+ if (!new_fp) {
+ close(new_fd);
+ goto unlink_new;
+ }
+
+ /* Backup file is "/etc/passwd-" */
+ last_char[0] = '-';
+ /* Delete old one, create new as a hardlink to current */
+ i = (unlink(new_name) && errno != ENOENT);
+ if (i || link(filename, new_name))
+ bb_perror_msg("warning: cannot create backup copy '%s'", new_name);
+ last_char[0] = '+';
+
+ /* Lock the password file before updating */
+ lock.l_type = F_WRLCK;
+ lock.l_whence = SEEK_SET;
+ lock.l_start = 0;
+ lock.l_len = 0;
+ if (fcntl(old_fd, F_SETLK, &lock) < 0)
+ bb_perror_msg("warning: cannot lock '%s'", filename);
+ lock.l_type = F_UNLCK;
+
+ /* Read current password file, write updated one */
+ while (1) {
+ char *line = xmalloc_fgets(old_fp);
+ if (!line) break; /* EOF/error */
+ if (strncmp(username, line, user_len) == 0) {
+ /* we have a match with "username:"... */
+ const char *cp = line + user_len;
+ /* now cp -> old passwd, skip it: */
+ cp = strchr(cp, ':');
+ if (!cp) cp = "";
+ /* now cp -> ':' after old passwd or -> "" */
+ fprintf(new_fp, "%s%s%s", username, new_pw, cp);
+ /* Erase password in memory */
+ } else
+ fputs(line, new_fp);
+ free(line);
+ }
+ fcntl(old_fd, F_SETLK, &lock);
+
+ /* We do want all of them to execute, thus | instead of || */
+ if ((ferror(old_fp) | fflush(new_fp) | fsync(new_fd) | fclose(new_fp))
+ || rename(new_name, filename)
+ ) {
+ /* At least one of those failed */
+ goto unlink_new;
+ }
+ ret = 0; /* whee, success! */
+
+ unlink_new:
+ if (ret) unlink(new_name);
+
+ close_old_fp:
+ fclose(old_fp);
+
+ free_mem:
+ if (ENABLE_FEATURE_CLEAN_UP) free(new_name);
+ if (ENABLE_FEATURE_CLEAN_UP) free((char*)username);
+ logmode = LOGMODE_BOTH;
+ return ret;
+}
+
+
+int passwd_main(int argc, char **argv);
+int passwd_main(int argc, char **argv)
+{
+ enum {
+ OPT_algo = 0x1, /* -a - password algorithm */
+ OPT_lock = 0x2, /* -l - lock account */
+ OPT_unlock = 0x4, /* -u - unlock account */
+ OPT_delete = 0x8, /* -d - delete password */
+ OPT_lud = 0xe,
+ STATE_ALGO_md5 = 0x10,
+ /*STATE_ALGO_des = 0x20, not needed yet */
+ };
+ unsigned opt;
+ const char *opt_a = "";
+ const char *filename;
+ char *myname;
+ char *name;
+ char *newp;
+ struct passwd *pw;
+ uid_t myuid;
+ struct rlimit rlimit_fsize;
+ char c;
+
+#if ENABLE_FEATURE_SHADOWPASSWDS
+ /* Using _r function to avoid pulling in static buffers */
+ struct spwd spw;
+ struct spwd *result;
+ char buffer[256];
+#endif
+
+ logmode = LOGMODE_BOTH;
+ openlog(applet_name, LOG_NOWAIT, LOG_AUTH);
+ opt = getopt32(argc, argv, "a:lud", &opt_a);
+ argc -= optind;
+ argv += optind;
+
+ if (strcasecmp(opt_a, "des") != 0) /* -a */
+ opt |= STATE_ALGO_md5;
+ //else
+ // opt |= STATE_ALGO_des;
+ myuid = getuid();
+ if ((opt & OPT_lud) && (!argc || myuid))
+ bb_show_usage();
+
+ myname = xstrdup(bb_getpwuid(NULL, myuid, -1));
+ name = argc ? argv[0] : myname;
+
+ pw = getpwnam(name);
+ if (!pw) bb_error_msg_and_die("unknown user %s", name);
+ if (myuid && pw->pw_uid != myuid) {
+ /* LOGMODE_BOTH */
+ bb_error_msg_and_die("%s can't change password for %s", myname, name);
+ }
+
+ filename = bb_path_passwd_file;
+#if ENABLE_FEATURE_SHADOWPASSWDS
+ if (getspnam_r(pw->pw_name, &spw, buffer, sizeof(buffer), &result)) {
+ /* LOGMODE_BOTH */
+ bb_error_msg("no record of %s in %s, using %s",
+ name, bb_path_shadow_file,
+ bb_path_passwd_file);
+ } else {
+ filename = bb_path_shadow_file;
+ pw->pw_passwd = spw.sp_pwdp;
+ }
+#endif
+
+ /* Decide what the new password will be */
+ newp = NULL;
+ c = pw->pw_passwd[0] - '!';
+ if (!(opt & OPT_lud)) {
+ if (myuid && !c) { /* passwd starts with '!' */
+ /* LOGMODE_BOTH */
+ bb_error_msg_and_die("cannot change "
+ "locked password for %s", name);
+ }
+ printf("Changing password for %s\n", name);
+ newp = new_password(pw, myuid, opt & STATE_ALGO_md5);
+ if (!newp) {
+ logmode = LOGMODE_STDIO;
+ bb_error_msg_and_die("password for %s is unchanged", name);
+ }
+ } else if (opt & OPT_lock) {
+ if (!c) goto skip; /* passwd starts with '!' */
+ newp = xasprintf("!%s", pw->pw_passwd);
+ } else if (opt & OPT_unlock) {
+ if (c) goto skip; /* not '!' */
+ newp = xstrdup(&pw->pw_passwd[1]);
+ } else if (opt & OPT_delete) {
+ newp = xstrdup("");
+ }
+
+ rlimit_fsize.rlim_cur = rlimit_fsize.rlim_max = 512L * 30000;
+ setrlimit(RLIMIT_FSIZE, &rlimit_fsize);
+ signal(SIGHUP, SIG_IGN);
+ signal(SIGINT, SIG_IGN);
+ signal(SIGQUIT, SIG_IGN);
+ umask(077);
+ xsetuid(0);
+ if (update_passwd(filename, name, newp) != 0) {
+ /* LOGMODE_BOTH */
+ bb_error_msg_and_die("cannot update password file %s",
+ filename);
+ }
+ /* LOGMODE_BOTH */
+ bb_info_msg("Password for %s changed by %s", name, myname);
+
+ if (ENABLE_FEATURE_CLEAN_UP) free(newp);
+skip:
+ if (!newp) {
+ bb_error_msg_and_die("password for %s is already %slocked",
+ name, (opt & OPT_unlock) ? "un" : "");
+ }
+ if (ENABLE_FEATURE_CLEAN_UP) free(myname);
+ return 0;
+}