--- trunk/mkinitrd-magellan/busybox/loginutils/passwd.c 2007/09/01 22:45:15 532 +++ trunk/mkinitrd-magellan/busybox/loginutils/passwd.c 2009/04/24 18:33:46 816 @@ -3,74 +3,37 @@ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. */ -#include "busybox.h" +#include "libbb.h" #include - 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 *orig = (char*)""; char *newp = NULL; - char *cipher = NULL; char *cp = NULL; char *ret = NULL; /* failure so far */ if (myuid && pw->pw_passwd[0]) { + char *encrypted; + 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'", + encrypted = pw_encrypt(orig, pw->pw_passwd, 1); /* returns malloced str */ + if (strcmp(encrypted, 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; } + if (ENABLE_FEATURE_CLEAN_UP) free(encrypted); } orig = xstrdup(orig); /* or else bb_askpass() will destroy it */ newp = bb_askpass(0, "New password:"); /* returns ptr to static */ @@ -89,13 +52,13 @@ goto err_ret; } - /*memset(salt, 0, sizeof(salt)); - why?*/ - crypt_make_salt(salt, 1); /* des */ + crypt_make_salt(salt, 1, 0); /* des */ if (algo) { /* MD5 */ strcpy(salt, "$1$"); - crypt_make_salt(salt + 3, 4); + crypt_make_salt(salt + 3, 4, 0); } - ret = xstrdup(pw_encrypt(newp, salt)); /* returns ptr to static */ + /* pw_encrypt returns malloced str */ + ret = pw_encrypt(newp, salt, 1); /* whee, success! */ err_ret: @@ -103,133 +66,12 @@ 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) MAIN_EXTERNALLY_VISIBLE; +int passwd_main(int argc UNUSED_PARAM, char **argv) { enum { OPT_algo = 0x1, /* -a - password algorithm */ @@ -238,10 +80,11 @@ OPT_delete = 0x8, /* -d - delete password */ OPT_lud = 0xe, STATE_ALGO_md5 = 0x10, - /*STATE_ALGO_des = 0x20, not needed yet */ + //STATE_ALGO_des = 0x20, not needed yet }; unsigned opt; - char *opt_a = ""; + int rc; + const char *opt_a = ""; const char *filename; char *myname; char *name; @@ -250,11 +93,16 @@ 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; + char buffer[256]; +#endif logmode = LOGMODE_BOTH; openlog(applet_name, LOG_NOWAIT, LOG_AUTH); - opt = getopt32(argc, argv, "a:lud", &opt_a); - argc -= optind; + opt = getopt32(argv, "a:lud", &opt_a); + //argc -= optind; argv += optind; if (strcasecmp(opt_a, "des") != 0) /* -a */ @@ -262,31 +110,35 @@ //else // opt |= STATE_ALGO_des; myuid = getuid(); - if ((opt & OPT_lud) && (!argc || myuid)) + /* -l, -u, -d require root priv and username argument */ + if ((opt & OPT_lud) && (myuid || !argv[0])) bb_show_usage(); - myname = xstrdup(bb_getpwuid(NULL, myuid, -1)); - name = argc ? argv[0] : myname; + /* Will complain and die if username not found */ + myname = xstrdup(bb_getpwuid(NULL, -1, myuid)); + name = argv[0] ? argv[0] : myname; pw = getpwnam(name); - if (!pw) bb_error_msg_and_die("unknown user %s", 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 { - struct spwd *sp = getspnam(name); - if (!sp) { + /* getspnam_r may return 0 yet set result to NULL. + * At least glibc 2.4 does this. Be extra paranoid here. */ + struct spwd *result = NULL; + if (getspnam_r(pw->pw_name, &spw, buffer, sizeof(buffer), &result) + || !result || strcmp(result->sp_namp, pw->pw_name) != 0) { /* 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 = sp->sp_pwdp; + pw->pw_passwd = result->sp_pwdp; } } #endif @@ -311,28 +163,41 @@ newp = xasprintf("!%s", pw->pw_passwd); } else if (opt & OPT_unlock) { if (c) goto skip; /* not '!' */ + /* pw->pw_passwd points to static storage, + * strdup'ing to avoid nasty surprizes */ newp = xstrdup(&pw->pw_passwd[1]); } else if (opt & OPT_delete) { - newp = xstrdup(""); + //newp = xstrdup(""); + newp = (char*)""; } 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); + bb_signals(0 + + (1 << SIGHUP) + + (1 << SIGINT) + + (1 << 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); + +#if ENABLE_FEATURE_SHADOWPASSWDS + filename = bb_path_shadow_file; + rc = update_passwd(bb_path_shadow_file, name, newp); + if (rc == 0) /* no lines updated, no errors detected */ +#endif + { + filename = bb_path_passwd_file; + rc = update_passwd(bb_path_passwd_file, name, newp); } /* LOGMODE_BOTH */ + if (rc < 0) + bb_error_msg_and_die("cannot update password file %s", + filename); bb_info_msg("Password for %s changed by %s", name, myname); - if (ENABLE_FEATURE_CLEAN_UP) free(newp); -skip: + //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" : "");