diff options
Diffstat (limited to 'release/src/router/busybox/loginutils/passwd.c')
| -rw-r--r-- | release/src/router/busybox/loginutils/passwd.c | 406 |
1 files changed, 406 insertions, 0 deletions
diff --git a/release/src/router/busybox/loginutils/passwd.c b/release/src/router/busybox/loginutils/passwd.c new file mode 100644 index 00000000..e8577066 --- /dev/null +++ b/release/src/router/busybox/loginutils/passwd.c @@ -0,0 +1,406 @@ +/* vi: set sw=4 ts=4: */ +#include <fcntl.h> +#include <stdio.h> +#include <string.h> +#include <signal.h> +#include <sys/stat.h> +#include <sys/types.h> +#include <unistd.h> +#include <utime.h> +#include <syslog.h> +#include <time.h> +#include <sys/resource.h> +#include <errno.h> + +#include "busybox.h" + +static char crypt_passwd[128]; + +static int create_backup(const char *backup, FILE * fp); +static int new_password(const struct passwd *pw, int amroot, int algo); +static void set_filesize_limit(int blocks); + + +int get_algo(char *a) +{ + int x = 1; /* standard: MD5 */ + + if (strcasecmp(a, "des") == 0) + x = 0; + return x; +} + + +extern int update_passwd(const struct passwd *pw, char *crypt_pw) +{ + char filename[1024]; + char buf[1025]; + char buffer[80]; + char username[32]; + char *pw_rest; + int has_shadow = 0; + int mask; + int continued; + FILE *fp; + FILE *out_fp; + struct stat sb; + struct flock lock; + + if (access(bb_path_shadow_file, F_OK) == 0) { + has_shadow = 1; + } + if (has_shadow) { + snprintf(filename, sizeof filename, "%s", bb_path_shadow_file); + } else { + snprintf(filename, sizeof filename, "%s", bb_path_passwd_file); + } + + if (((fp = fopen(filename, "r+")) == 0) || (fstat(fileno(fp), &sb))) { + /* return 0; */ + return 1; + } + + /* 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(fileno(fp), F_SETLK, &lock) < 0) { + fprintf(stderr, "%s: %s\n", filename, strerror(errno)); + return 1; + } + lock.l_type = F_UNLCK; + + snprintf(buf, sizeof buf, "%s-", filename); + if (create_backup(buf, fp)) { + fcntl(fileno(fp), F_SETLK, &lock); + fclose(fp); + return 1; + } + snprintf(buf, sizeof buf, "%s+", filename); + mask = umask(0777); + out_fp = fopen(buf, "w"); + umask(mask); + if ((!out_fp) || (fchmod(fileno(out_fp), sb.st_mode & 0777)) + || (fchown(fileno(out_fp), sb.st_uid, sb.st_gid))) { + fcntl(fileno(fp), F_SETLK, &lock); + fclose(fp); + fclose(out_fp); + return 1; + } + + continued = 0; + snprintf(username, sizeof username, "%s:", pw->pw_name); + rewind(fp); + while (!feof(fp)) { + fgets(buffer, sizeof buffer, fp); + if (!continued) { // Check to see if we're updating this line. + if (strncmp(username, buffer, strlen(username)) == 0) { // we have a match. + pw_rest = strchr(buffer, ':'); + *pw_rest++ = '\0'; + pw_rest = strchr(pw_rest, ':'); + fprintf(out_fp, "%s:%s%s", buffer, crypt_pw, pw_rest); + } else { + fputs(buffer, out_fp); + } + } else { + fputs(buffer, out_fp); + } + if (buffer[strlen(buffer) - 1] == '\n') { + continued = 0; + } else { + continued = 1; + } + bzero(buffer, sizeof buffer); + } + + if (fflush(out_fp) || fsync(fileno(out_fp)) || fclose(out_fp)) { + unlink(buf); + fcntl(fileno(fp), F_SETLK, &lock); + fclose(fp); + return 1; + } + if (rename(buf, filename) < 0) { + fcntl(fileno(fp), F_SETLK, &lock); + fclose(fp); + return 1; + } else { + fcntl(fileno(fp), F_SETLK, &lock); + fclose(fp); + return 0; + } +} + + +extern int passwd_main(int argc, char **argv) +{ + int amroot; + char *cp; + char *np; + char *name; + char *myname; + int flag; + int algo = 0; /* -a - password algorithm */ + int lflg = 0; /* -l - lock account */ + int uflg = 0; /* -u - unlock account */ + int dflg = 0; /* -d - delete password */ + const struct passwd *pw; + unsigned short ruid; + +#ifdef CONFIG_FEATURE_SHADOWPASSWDS + const struct spwd *sp; +#endif /* CONFIG_FEATURE_SHADOWPASSWDS */ + amroot = (getuid() == 0); + openlog("passwd", LOG_PID | LOG_CONS | LOG_NOWAIT, LOG_AUTH); + while ((flag = getopt(argc, argv, "a:dlu")) != EOF) { + switch (flag) { + case 'a': + algo = get_algo(optarg); + break; + case 'd': + dflg++; + break; + case 'l': + lflg++; + break; + case 'u': + uflg++; + break; + default: + bb_show_usage(); + } + } + ruid = getuid(); + pw = (struct passwd *) getpwuid(ruid); + if (!pw) { + bb_error_msg_and_die("Cannot determine your user name."); + } + myname = (char *) bb_xstrdup(pw->pw_name); + if (optind < argc) { + name = argv[optind]; + } else { + name = myname; + } + if ((lflg || uflg || dflg) && (optind >= argc || !amroot)) { + bb_show_usage(); + } + pw = getpwnam(name); + if (!pw) { + bb_error_msg_and_die("Unknown user %s\n", name); + } + if (!amroot && pw->pw_uid != getuid()) { + syslog(LOG_WARNING, "can't change pwd for `%s'", name); + bb_error_msg_and_die("Permission denied.\n"); + } +#ifdef CONFIG_FEATURE_SHADOWPASSWDS + sp = getspnam(name); + if (!sp) { + sp = (struct spwd *) pwd_to_spwd(pw); + } + cp = sp->sp_pwdp; + np = sp->sp_namp; +#else + cp = pw->pw_passwd; + np = name; +#endif /* CONFIG_FEATURE_SHADOWPASSWDS */ + + safe_strncpy(crypt_passwd, cp, sizeof(crypt_passwd)); + if (!(dflg || lflg || uflg)) { + if (!amroot) { + if (cp[0] == '!') { + syslog(LOG_WARNING, "password locked for `%s'", np); + bb_error_msg_and_die( "The password for `%s' cannot be changed.\n", np); + } + } + printf("Changing password for %s\n", name); + if (new_password(pw, amroot, algo)) { + bb_error_msg_and_die( "The password for %s is unchanged.\n", name); + } + } else if (lflg) { + if (crypt_passwd[0] != '!') { + memmove(&crypt_passwd[1], crypt_passwd, + sizeof crypt_passwd - 1); + crypt_passwd[sizeof crypt_passwd - 1] = '\0'; + crypt_passwd[0] = '!'; + } + } else if (uflg) { + if (crypt_passwd[0] == '!') { + memmove(crypt_passwd, &crypt_passwd[1], + sizeof crypt_passwd - 1); + } + } else if (dflg) { + crypt_passwd[0] = '\0'; + } + set_filesize_limit(30000); + signal(SIGHUP, SIG_IGN); + signal(SIGINT, SIG_IGN); + signal(SIGQUIT, SIG_IGN); + umask(077); + if (setuid(0)) { + syslog(LOG_ERR, "can't setuid(0)"); + bb_error_msg_and_die( "Cannot change ID to root.\n"); + } + if (!update_passwd(pw, crypt_passwd)) { + syslog(LOG_INFO, "password for `%s' changed by user `%s'", name, + myname); + printf("Password changed.\n"); + } else { + syslog(LOG_WARNING, "an error occurred updating the password file"); + bb_error_msg_and_die("An error occurred updating the password file.\n"); + } + return (0); +} + + + +static int create_backup(const char *backup, FILE * fp) +{ + struct stat sb; + struct utimbuf ub; + FILE *bkfp; + int c, mask; + + if (fstat(fileno(fp), &sb)) + /* return -1; */ + return 1; + + mask = umask(077); + bkfp = fopen(backup, "w"); + umask(mask); + if (!bkfp) + /* return -1; */ + return 1; + + /* TODO: faster copy, not one-char-at-a-time. --marekm */ + rewind(fp); + while ((c = getc(fp)) != EOF) { + if (putc(c, bkfp) == EOF) + break; + } + if (c != EOF || fflush(bkfp)) { + fclose(bkfp); + /* return -1; */ + return 1; + } + if (fclose(bkfp)) + /* return -1; */ + return 1; + + ub.actime = sb.st_atime; + ub.modtime = sb.st_mtime; + utime(backup, &ub); + return 0; +} + +static int i64c(int i) +{ + if (i <= 0) + return ('.'); + if (i == 1) + return ('/'); + if (i >= 2 && i < 12) + return ('0' - 2 + i); + if (i >= 12 && i < 38) + return ('A' - 12 + i); + if (i >= 38 && i < 63) + return ('a' - 38 + i); + return ('z'); +} + +static char *crypt_make_salt(void) +{ + time_t now; + static unsigned long x; + static char result[3]; + + time(&now); + x += now + getpid() + clock(); + result[0] = i64c(((x >> 18) ^ (x >> 6)) & 077); + result[1] = i64c(((x >> 12) ^ x) & 077); + result[2] = '\0'; + return result; +} + + +static int new_password(const struct passwd *pw, int amroot, int algo) +{ + char *clear; + char *cipher; + char *cp; + char orig[200]; + char pass[200]; + time_t start, now; + + if (!amroot && crypt_passwd[0]) { + if (!(clear = getpass("Old password:"))) { + /* return -1; */ + return 1; + } + cipher = pw_encrypt(clear, crypt_passwd); + if (strcmp(cipher, crypt_passwd) != 0) { + syslog(LOG_WARNING, "incorrect password for `%s'", + pw->pw_name); + time(&start); + now = start; + while (difftime(now, start) < FAIL_DELAY) { + sleep(FAIL_DELAY); + time(&now); + } + fprintf(stderr, "Incorrect password.\n"); + /* return -1; */ + return 1; + } + safe_strncpy(orig, clear, sizeof(orig)); + bzero(clear, strlen(clear)); + bzero(cipher, strlen(cipher)); + } else { + orig[0] = '\0'; + } + if (! (cp=getpass("Enter the new password (minimum of 5, maximum of 8 characters)\n" + "Please use a combination of upper and lower case letters and numbers.\n" + "Enter new password: "))) + { + bzero(orig, sizeof orig); + /* return -1; */ + return 1; + } + safe_strncpy(pass, cp, sizeof(pass)); + bzero(cp, strlen(cp)); + /* if (!obscure(orig, pass, pw)) { */ + if (obscure(orig, pass, pw)) { + if (amroot) { + printf("\nWarning: weak password (continuing).\n"); + } else { + /* return -1; */ + return 1; + } + } + if (!(cp = getpass("Re-enter new password: "))) { + bzero(orig, sizeof orig); + /* return -1; */ + return 1; + } + if (strcmp(cp, pass)) { + fprintf(stderr, "Passwords do not match.\n"); + /* return -1; */ + return 1; + } + bzero(cp, strlen(cp)); + bzero(orig, sizeof(orig)); + + if (algo == 1) { + cp = pw_encrypt(pass, "$1$"); + } else + cp = pw_encrypt(pass, crypt_make_salt()); + bzero(pass, sizeof pass); + safe_strncpy(crypt_passwd, cp, sizeof(crypt_passwd)); + return 0; +} + +static void set_filesize_limit(int blocks) +{ + struct rlimit rlimit_fsize; + + rlimit_fsize.rlim_cur = rlimit_fsize.rlim_max = 512L * blocks; + setrlimit(RLIMIT_FSIZE, &rlimit_fsize); +} |