/* * EAP peer method: EAP-FAST PAC file processing * Copyright (c) 2004-2006, Jouni Malinen * * This software may be distributed under the terms of the BSD license. * See README for more details. */ #include "includes.h" #include "os.h" #include "utils/common.h" #include "eap_peer/eap_config.h" #include "eap_peer/eap_i.h" #include "eap_peer/eap_fast_pac.h" /* TODO: encrypt PAC-Key in the PAC file */ /* Text data format */ static const char *pac_file_hdr = "wpa_supplicant EAP-FAST PAC file - version 1"; /* * Binary data format * 4-octet magic value: 6A E4 92 0C * 2-octet version (big endian) * * * version=0: * Sequence of PAC entries: * 2-octet PAC-Type (big endian) * 32-octet PAC-Key * 2-octet PAC-Opaque length (big endian) * PAC-Opaque data (length bytes) * 2-octet PAC-Info length (big endian) * PAC-Info data (length bytes) */ #define EAP_FAST_PAC_BINARY_MAGIC 0x6ae4920c #define EAP_FAST_PAC_BINARY_FORMAT_VERSION 0 /** * eap_fast_free_pac - Free PAC data * @pac: Pointer to the PAC entry * * Note that the PAC entry must not be in a list since this function does not * remove the list links. */ void eap_fast_free_pac(struct eap_fast_pac *pac) { os_free(pac->pac_opaque); os_free(pac->pac_info); os_free(pac->a_id); os_free(pac->i_id); os_free(pac->a_id_info); os_free(pac); } /** * eap_fast_get_pac - Get a PAC entry based on A-ID * @pac_root: Pointer to root of the PAC list * @a_id: A-ID to search for * @a_id_len: Length of A-ID * @pac_type: PAC-Type to search for * Returns: Pointer to the PAC entry, or %NULL if A-ID not found */ struct eap_fast_pac * eap_fast_get_pac(struct eap_fast_pac *pac_root, const u8 *a_id, size_t a_id_len, u16 pac_type) { struct eap_fast_pac *pac = pac_root; while (pac) { if (pac->pac_type == pac_type && pac->a_id_len == a_id_len && os_memcmp(pac->a_id, a_id, a_id_len) == 0) { return pac; } pac = pac->next; } return NULL; } static void eap_fast_remove_pac(struct eap_fast_pac **pac_root, struct eap_fast_pac **pac_current, const u8 *a_id, size_t a_id_len, u16 pac_type) { struct eap_fast_pac *pac, *prev; pac = *pac_root; prev = NULL; while (pac) { if (pac->pac_type == pac_type && pac->a_id_len == a_id_len && os_memcmp(pac->a_id, a_id, a_id_len) == 0) { if (prev == NULL) *pac_root = pac->next; else prev->next = pac->next; if (*pac_current == pac) *pac_current = NULL; eap_fast_free_pac(pac); break; } prev = pac; pac = pac->next; } } static int eap_fast_copy_buf(u8 **dst, size_t *dst_len, const u8 *src, size_t src_len) { if (src) { *dst = os_memdup(src, src_len); if (*dst == NULL) return -1; *dst_len = src_len; } return 0; } /** * eap_fast_add_pac - Add a copy of a PAC entry to a list * @pac_root: Pointer to PAC list root pointer * @pac_current: Pointer to the current PAC pointer * @entry: New entry to clone and add to the list * Returns: 0 on success, -1 on failure * * This function makes a clone of the given PAC entry and adds this copied * entry to the list (pac_root). If an old entry for the same A-ID is found, * it will be removed from the PAC list and in this case, pac_current entry * is set to %NULL if it was the removed entry. */ int eap_fast_add_pac(struct eap_fast_pac **pac_root, struct eap_fast_pac **pac_current, struct eap_fast_pac *entry) { struct eap_fast_pac *pac; if (entry == NULL || entry->a_id == NULL) return -1; /* Remove a possible old entry for the matching A-ID. */ eap_fast_remove_pac(pac_root, pac_current, entry->a_id, entry->a_id_len, entry->pac_type); /* Allocate a new entry and add it to the list of PACs. */ pac = os_zalloc(sizeof(*pac)); if (pac == NULL) return -1; pac->pac_type = entry->pac_type; os_memcpy(pac->pac_key, entry->pac_key, EAP_FAST_PAC_KEY_LEN); if (eap_fast_copy_buf(&pac->pac_opaque, &pac->pac_opaque_len, entry->pac_opaque, entry->pac_opaque_len) < 0 || eap_fast_copy_buf(&pac->pac_info, &pac->pac_info_len, entry->pac_info, entry->pac_info_len) < 0 || eap_fast_copy_buf(&pac->a_id, &pac->a_id_len, entry->a_id, entry->a_id_len) < 0 || eap_fast_copy_buf(&pac->i_id, &pac->i_id_len, entry->i_id, entry->i_id_len) < 0 || eap_fast_copy_buf(&pac->a_id_info, &pac->a_id_info_len, entry->a_id_info, entry->a_id_info_len) < 0) { eap_fast_free_pac(pac); return -1; } pac->next = *pac_root; *pac_root = pac; return 0; } struct eap_fast_read_ctx { FILE *f; const char *pos; const char *end; int line; char *buf; size_t buf_len; }; static int eap_fast_read_line(struct eap_fast_read_ctx *rc, char **value) { char *pos; rc->line++; if (rc->f) { if (fgets(rc->buf, rc->buf_len, rc->f) == NULL) return -1; } else { const char *l_end; size_t len; if (rc->pos >= rc->end) return -1; l_end = rc->pos; while (l_end < rc->end && *l_end != '\n') l_end++; len = l_end - rc->pos; if (len >= rc->buf_len) len = rc->buf_len - 1; os_memcpy(rc->buf, rc->pos, len); rc->buf[len] = '\0'; rc->pos = l_end + 1; } rc->buf[rc->buf_len - 1] = '\0'; pos = rc->buf; while (*pos != '\0') { if (*pos == '\n' || *pos == '\r') { *pos = '\0'; break; } pos++; } pos = os_strchr(rc->buf, '='); if (pos) *pos++ = '\0'; *value = pos; return 0; } static u8 * eap_fast_parse_hex(const char *value, size_t *len) { int hlen; u8 *buf; if (value == NULL) return NULL; hlen = os_strlen(value); if (hlen & 1) return NULL; *len = hlen / 2; buf = os_malloc(*len); if (buf == NULL) return NULL; if (hexstr2bin(value, buf, *len)) { os_free(buf); return NULL; } return buf; } static int eap_fast_init_pac_data(struct eap_sm *sm, const char *pac_file, struct eap_fast_read_ctx *rc) { os_memset(rc, 0, sizeof(*rc)); rc->buf_len = 2048; rc->buf = os_malloc(rc->buf_len); if (rc->buf == NULL) return -1; if (os_strncmp(pac_file, "blob://", 7) == 0) { const struct wpa_config_blob *blob; blob = eap_get_config_blob(sm, pac_file); if (blob == NULL) { wpa_printf(MSG_INFO, "EAP-FAST: No PAC blob '%s' - " "assume no PAC entries have been " "provisioned", pac_file); os_free(rc->buf); return -1; } rc->pos = (char *) blob->data; rc->end = (char *) blob->data + blob->len; } else { rc->f = fopen(pac_file, "rb"); if (rc->f == NULL) { wpa_printf(MSG_INFO, "EAP-FAST: No PAC file '%s' - " "assume no PAC entries have been " "provisioned", pac_file); os_free(rc->buf); return -1; } } return 0; } static void eap_fast_deinit_pac_data(struct eap_fast_read_ctx *rc) { os_free(rc->buf); if (rc->f) fclose(rc->f); } static const char * eap_fast_parse_start(struct eap_fast_pac **pac) { if (*pac) return "START line without END"; *pac = os_zalloc(sizeof(struct eap_fast_pac)); if (*pac == NULL) return "No memory for PAC entry"; (*pac)->pac_type = PAC_TYPE_TUNNEL_PAC; return NULL; } static const char * eap_fast_parse_end(struct eap_fast_pac **pac_root, struct eap_fast_pac **pac) { if (*pac == NULL) return "END line without START"; if (*pac_root) { struct eap_fast_pac *end = *pac_root; while (end->next) end = end->next; end->next = *pac; } else *pac_root = *pac; *pac = NULL; return NULL; } static const char * eap_fast_parse_pac_type(struct eap_fast_pac *pac, char *pos) { if (!pos) return "Cannot parse pac type"; pac->pac_type = atoi(pos); if (pac->pac_type != PAC_TYPE_TUNNEL_PAC && pac->pac_type != PAC_TYPE_USER_AUTHORIZATION && pac->pac_type != PAC_TYPE_MACHINE_AUTHENTICATION) return "Unrecognized PAC-Type"; return NULL; } static const char * eap_fast_parse_pac_key(struct eap_fast_pac *pac, char *pos) { u8 *key; size_t key_len; key = eap_fast_parse_hex(pos, &key_len); if (key == NULL || key_len != EAP_FAST_PAC_KEY_LEN) { os_free(key); return "Invalid PAC-Key"; } os_memcpy(pac->pac_key, key, EAP_FAST_PAC_KEY_LEN); os_free(key); return NULL; } static const char * eap_fast_parse_pac_opaque(struct eap_fast_pac *pac, char *pos) { os_free(pac->pac_opaque); pac->pac_opaque = eap_fast_parse_hex(pos, &pac->pac_opaque_len); if (pac->pac_opaque == NULL) return "Invalid PAC-Opaque"; return NULL; } static const char * eap_fast_parse_a_id(struct eap_fast_pac *pac, char *pos) { os_free(pac->a_id); pac->a_id = eap_fast_parse_hex(pos, &pac->a_id_len); if (pac->a_id == NULL) return "Invalid A-ID"; return NULL; } static const char * eap_fast_parse_i_id(struct eap_fast_pac *pac, char *pos) { os_free(pac->i_id); pac->i_id = eap_fast_parse_hex(pos, &pac->i_id_len); if (pac->i_id == NULL) return "Invalid I-ID"; return NULL; } static const char * eap_fast_parse_a_id_info(struct eap_fast_pac *pac, char *pos) { os_free(pac->a_id_info); pac->a_id_info = eap_fast_parse_hex(pos, &pac->a_id_info_len); if (pac->a_id_info == NULL) return "Invalid A-ID-Info"; return NULL; } /** * eap_fast_load_pac - Load PAC entries (text format) * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init() * @pac_root: Pointer to root of the PAC list (to be filled) * @pac_file: Name of the PAC file/blob to load * Returns: 0 on success, -1 on failure */ int eap_fast_load_pac(struct eap_sm *sm, struct eap_fast_pac **pac_root, const char *pac_file) { struct eap_fast_read_ctx rc; struct eap_fast_pac *pac = NULL; int count = 0; char *pos; const char *err = NULL; if (pac_file == NULL) return -1; if (eap_fast_init_pac_data(sm, pac_file, &rc) < 0) return 0; if (eap_fast_read_line(&rc, &pos) < 0) { /* empty file - assume it is fine to overwrite */ printf("\n\nassuming it is fine to overwrite... \n\n"); eap_fast_deinit_pac_data(&rc); return 0; } printf("\n\nPAC FILE =\n%s", rc.pos); if (os_strcmp(pac_file_hdr, rc.buf) != 0) err = "Unrecognized header line"; while (!err && eap_fast_read_line(&rc, &pos) == 0) { if (os_strcmp(rc.buf, "START") == 0) err = eap_fast_parse_start(&pac); else if (os_strcmp(rc.buf, "END") == 0) { err = eap_fast_parse_end(pac_root, &pac); count++; } else if (!pac) err = "Unexpected line outside START/END block"; else if (os_strcmp(rc.buf, "PAC-Type") == 0) err = eap_fast_parse_pac_type(pac, pos); else if (os_strcmp(rc.buf, "PAC-Key") == 0) err = eap_fast_parse_pac_key(pac, pos); else if (os_strcmp(rc.buf, "PAC-Opaque") == 0) err = eap_fast_parse_pac_opaque(pac, pos); else if (os_strcmp(rc.buf, "A-ID") == 0) err = eap_fast_parse_a_id(pac, pos); else if (os_strcmp(rc.buf, "I-ID") == 0) err = eap_fast_parse_i_id(pac, pos); else if (os_strcmp(rc.buf, "A-ID-Info") == 0) err = eap_fast_parse_a_id_info(pac, pos); } if (pac) { if (!err) err = "PAC block not terminated with END"; eap_fast_free_pac(pac); } eap_fast_deinit_pac_data(&rc); if (err) { wpa_printf(MSG_INFO, "EAP-FAST: %s in '%s:%d'", err, pac_file, rc.line); return -1; } wpa_printf(MSG_DEBUG, "EAP-FAST: Read %d PAC entries from '%s'", count, pac_file); return 0; } static void eap_fast_write(char **buf, char **pos, size_t *buf_len, const char *field, const u8 *data, size_t len, int txt) { size_t i, need; int ret; char *end; if (data == NULL || buf == NULL || *buf == NULL || pos == NULL || *pos == NULL || *pos < *buf) return; need = os_strlen(field) + len * 2 + 30; if (txt) need += os_strlen(field) + len + 20; if (*pos - *buf + need > *buf_len) { char *nbuf = os_realloc(*buf, *buf_len + need); if (nbuf == NULL) { os_free(*buf); *buf = NULL; return; } *pos = nbuf + (*pos - *buf); *buf = nbuf; *buf_len += need; } end = *buf + *buf_len; ret = os_snprintf(*pos, end - *pos, "%s=", field); if (os_snprintf_error(end - *pos, ret)) return; *pos += ret; *pos += wpa_snprintf_hex(*pos, end - *pos, data, len); ret = os_snprintf(*pos, end - *pos, "\n"); if (os_snprintf_error(end - *pos, ret)) return; *pos += ret; if (txt) { ret = os_snprintf(*pos, end - *pos, "%s-txt=", field); if (os_snprintf_error(end - *pos, ret)) return; *pos += ret; for (i = 0; i < len; i++) { ret = os_snprintf(*pos, end - *pos, "%c", data[i]); if (os_snprintf_error(end - *pos, ret)) return; *pos += ret; } ret = os_snprintf(*pos, end - *pos, "\n"); if (os_snprintf_error(end - *pos, ret)) return; *pos += ret; } } static int eap_fast_write_pac(struct eap_sm *sm, const char *pac_file, char *buf, size_t len) { if (os_strncmp(pac_file, "blob://", 7) == 0) { struct wpa_config_blob *blob; blob = os_zalloc(sizeof(*blob)); if (blob == NULL) return -1; blob->data = (u8 *) buf; blob->len = len; buf = NULL; blob->name = os_strdup(pac_file + 7); if (blob->name == NULL) { os_free(blob); return -1; } eap_set_config_blob(sm, blob); os_free(blob); } else { FILE *f; f = fopen(pac_file, "wb"); if (f == NULL) { wpa_printf(MSG_INFO, "EAP-FAST: Failed to open PAC " "file '%s' for writing", pac_file); return -1; } if (fwrite(buf, 1, len, f) != len) { wpa_printf(MSG_INFO, "EAP-FAST: Failed to write all " "PACs into '%s'", pac_file); fclose(f); return -1; } os_free(buf); fclose(f); } return 0; } static int eap_fast_add_pac_data(struct eap_fast_pac *pac, char **buf, char **pos, size_t *buf_len) { int ret; ret = os_snprintf(*pos, *buf + *buf_len - *pos, "START\nPAC-Type=%d\n", pac->pac_type); if (os_snprintf_error(*buf + *buf_len - *pos, ret)) return -1; *pos += ret; eap_fast_write(buf, pos, buf_len, "PAC-Key", pac->pac_key, EAP_FAST_PAC_KEY_LEN, 0); eap_fast_write(buf, pos, buf_len, "PAC-Opaque", pac->pac_opaque, pac->pac_opaque_len, 0); eap_fast_write(buf, pos, buf_len, "PAC-Info", pac->pac_info, pac->pac_info_len, 0); eap_fast_write(buf, pos, buf_len, "A-ID", pac->a_id, pac->a_id_len, 0); eap_fast_write(buf, pos, buf_len, "I-ID", pac->i_id, pac->i_id_len, 1); eap_fast_write(buf, pos, buf_len, "A-ID-Info", pac->a_id_info, pac->a_id_info_len, 1); if (*buf == NULL) { wpa_printf(MSG_DEBUG, "EAP-FAST: No memory for PAC " "data"); return -1; } ret = os_snprintf(*pos, *buf + *buf_len - *pos, "END\n"); if (os_snprintf_error(*buf + *buf_len - *pos, ret)) return -1; *pos += ret; return 0; } /** * eap_fast_save_pac - Save PAC entries (text format) * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init() * @pac_root: Root of the PAC list * @pac_file: Name of the PAC file/blob * Returns: 0 on success, -1 on failure */ int eap_fast_save_pac(struct eap_sm *sm, struct eap_fast_pac *pac_root, const char *pac_file) { struct eap_fast_pac *pac; int ret, count = 0; char *buf, *pos; size_t buf_len; if (pac_file == NULL) return -1; buf_len = 1024; pos = buf = os_malloc(buf_len); if (buf == NULL) return -1; ret = os_snprintf(pos, buf + buf_len - pos, "%s\n", pac_file_hdr); if (os_snprintf_error(buf + buf_len - pos, ret)) { os_free(buf); return -1; } pos += ret; pac = pac_root; while (pac) { if (eap_fast_add_pac_data(pac, &buf, &pos, &buf_len)) { os_free(buf); return -1; } count++; pac = pac->next; } if (eap_fast_write_pac(sm, pac_file, buf, pos - buf)) { os_free(buf); return -1; } wpa_printf(MSG_DEBUG, "PAC file: %s", (sm->blob[3].data)); wpa_printf(MSG_DEBUG, "EAP-FAST: Wrote %d PAC entries into '%s'", count, pac_file); return 0; } /** * eap_fast_pac_list_truncate - Truncate a PAC list to the given length * @pac_root: Root of the PAC list * @max_len: Maximum length of the list (>= 1) * Returns: Number of PAC entries removed */ size_t eap_fast_pac_list_truncate(struct eap_fast_pac *pac_root, size_t max_len) { struct eap_fast_pac *pac, *prev; size_t count; pac = pac_root; prev = NULL; count = 0; while (pac) { count++; if (count > max_len) break; prev = pac; pac = pac->next; } if (count <= max_len || prev == NULL) return 0; count = 0; prev->next = NULL; while (pac) { prev = pac; pac = pac->next; eap_fast_free_pac(prev); count++; } return count; } static void eap_fast_pac_get_a_id(struct eap_fast_pac *pac) { u8 *pos, *end; u16 type, len; pos = pac->pac_info; end = pos + pac->pac_info_len; while (end - pos > 4) { type = WPA_GET_BE16(pos); pos += 2; len = WPA_GET_BE16(pos); pos += 2; if (len > (unsigned int) (end - pos)) break; if (type == PAC_TYPE_A_ID) { os_free(pac->a_id); pac->a_id = os_memdup(pos, len); if (pac->a_id == NULL) break; pac->a_id_len = len; } if (type == PAC_TYPE_A_ID_INFO) { os_free(pac->a_id_info); pac->a_id_info = os_memdup(pos, len); if (pac->a_id_info == NULL) break; pac->a_id_info_len = len; } pos += len; } } /** * eap_fast_load_pac_bin - Load PAC entries (binary format) * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init() * @pac_root: Pointer to root of the PAC list (to be filled) * @pac_file: Name of the PAC file/blob to load * Returns: 0 on success, -1 on failure */ int eap_fast_load_pac_bin(struct eap_sm *sm, struct eap_fast_pac **pac_root, const char *pac_file) { const struct wpa_config_blob *blob = NULL; u8 *buf, *end, *pos; size_t len = 0; size_t count = 0; struct eap_fast_pac *pac, *prev; *pac_root = NULL; if (pac_file == NULL) return -1; if (sm->config.pac_file != NULL) { //if (os_strncmp(pac_file, "blob://", 7) == 0) { blob = eap_get_config_blob(sm, PAC_FILE_NAME); if (blob == NULL) { wpa_printf(MSG_INFO, "EAP-FAST: No PAC blob '%s' - " "assume no PAC entries have been " "provisioned", pac_file); return 0; } buf = (u8 *) blob->data; len = blob->len; } else { buf = (u8 *) sm->blob[3].data; //(u8 *) os_readfile(pac_file, &len); if (buf == NULL) { wpa_printf(MSG_INFO, "EAP-FAST: No PAC file '%s' - " "assume no PAC entries have been " "provisioned", pac_file); return 0; } } if (len == 0) { if (blob == NULL) os_free(buf); return 0; } if (len < 6 || WPA_GET_BE32(buf) != EAP_FAST_PAC_BINARY_MAGIC || WPA_GET_BE16(buf + 4) != EAP_FAST_PAC_BINARY_FORMAT_VERSION) { wpa_printf(MSG_INFO, "EAP-FAST: Invalid PAC file '%s' (bin)", pac_file); if (blob == NULL) os_free(buf); return -1; } pac = prev = NULL; pos = buf + 6; end = buf + len; while (pos < end) { u16 val; if (end - pos < 2 + EAP_FAST_PAC_KEY_LEN + 2 + 2) { pac = NULL; goto parse_fail; } pac = os_zalloc(sizeof(*pac)); if (pac == NULL) goto parse_fail; pac->pac_type = WPA_GET_BE16(pos); pos += 2; os_memcpy(pac->pac_key, pos, EAP_FAST_PAC_KEY_LEN); pos += EAP_FAST_PAC_KEY_LEN; val = WPA_GET_BE16(pos); pos += 2; if (val > end - pos) goto parse_fail; pac->pac_opaque_len = val; pac->pac_opaque = os_memdup(pos, pac->pac_opaque_len); if (pac->pac_opaque == NULL) goto parse_fail; pos += pac->pac_opaque_len; if (2 > end - pos) goto parse_fail; val = WPA_GET_BE16(pos); pos += 2; if (val > end - pos) goto parse_fail; pac->pac_info_len = val; pac->pac_info = os_memdup(pos, pac->pac_info_len); if (pac->pac_info == NULL) goto parse_fail; pos += pac->pac_info_len; eap_fast_pac_get_a_id(pac); count++; if (prev) prev->next = pac; else *pac_root = pac; prev = pac; } if (blob == NULL) os_free(buf); wpa_printf(MSG_DEBUG, "EAP-FAST: Read %lu PAC entries from '%s' (bin)", (unsigned long) count, pac_file); return 0; parse_fail: wpa_printf(MSG_INFO, "EAP-FAST: Failed to parse PAC file '%s' (bin)", pac_file); if (blob == NULL) os_free(buf); if (pac) eap_fast_free_pac(pac); return -1; } /** * eap_fast_save_pac_bin - Save PAC entries (binary format) * @sm: Pointer to EAP state machine allocated with eap_peer_sm_init() * @pac_root: Root of the PAC list * @pac_file: Name of the PAC file/blob * Returns: 0 on success, -1 on failure */ int eap_fast_save_pac_bin(struct eap_sm *sm, struct eap_fast_pac *pac_root, const char *pac_file) { size_t len, count = 0; struct eap_fast_pac *pac; u8 *buf, *pos; len = 6; pac = pac_root; while (pac) { if (pac->pac_opaque_len > 65535 || pac->pac_info_len > 65535) return -1; len += 2 + EAP_FAST_PAC_KEY_LEN + 2 + pac->pac_opaque_len + 2 + pac->pac_info_len; pac = pac->next; } buf = os_malloc(len); if (buf == NULL) return -1; pos = buf; WPA_PUT_BE32(pos, EAP_FAST_PAC_BINARY_MAGIC); pos += 4; WPA_PUT_BE16(pos, EAP_FAST_PAC_BINARY_FORMAT_VERSION); pos += 2; pac = pac_root; while (pac) { WPA_PUT_BE16(pos, pac->pac_type); pos += 2; os_memcpy(pos, pac->pac_key, EAP_FAST_PAC_KEY_LEN); pos += EAP_FAST_PAC_KEY_LEN; WPA_PUT_BE16(pos, pac->pac_opaque_len); pos += 2; os_memcpy(pos, pac->pac_opaque, pac->pac_opaque_len); pos += pac->pac_opaque_len; WPA_PUT_BE16(pos, pac->pac_info_len); pos += 2; os_memcpy(pos, pac->pac_info, pac->pac_info_len); pos += pac->pac_info_len; pac = pac->next; count++; } if (eap_fast_write_pac(sm, pac_file, (char *) buf, len)) { os_free(buf); return -1; } wpa_printf(MSG_DEBUG, "EAP-FAST: Wrote %lu PAC entries into '%s' " "(bin)", (unsigned long) count, pac_file); return 0; }