/* * RADIUS message processing * Copyright (c) 2002-2009, 2011-2015, Jouni Malinen <j@w1.fi> * * This software may be distributed under the terms of the BSD license. * See README for more details. */ #include "utils/includes.h" #include "utils/common.h" #include "utils/wpabuf.h" #include "crypto/md5.h" #include "crypto/crypto.h" #include "radius.h" /** * struct radius_msg - RADIUS message structure for new and parsed messages */ struct radius_msg { /** * buf - Allocated buffer for RADIUS message */ struct wpabuf *buf; /** * hdr - Pointer to the RADIUS header in buf */ struct radius_hdr *hdr; /** * attr_pos - Array of indexes to attributes * * The values are number of bytes from buf to the beginning of * struct radius_attr_hdr. */ size_t *attr_pos; /** * attr_size - Total size of the attribute pointer array */ size_t attr_size; /** * attr_used - Total number of attributes in the array */ size_t attr_used; }; struct radius_hdr * radius_msg_get_hdr(struct radius_msg *msg) { return msg->hdr; } struct wpabuf * radius_msg_get_buf(struct radius_msg *msg) { return msg->buf; } static struct radius_attr_hdr * radius_get_attr_hdr(struct radius_msg *msg, int idx) { return (struct radius_attr_hdr *) (wpabuf_mhead_u8(msg->buf) + msg->attr_pos[idx]); } static void radius_msg_set_hdr(struct radius_msg *msg, u8 code, u8 identifier) { msg->hdr->code = code; msg->hdr->identifier = identifier; } static int radius_msg_initialize(struct radius_msg *msg) { msg->attr_pos = os_calloc(RADIUS_DEFAULT_ATTR_COUNT, sizeof(*msg->attr_pos)); if (msg->attr_pos == NULL) return -1; msg->attr_size = RADIUS_DEFAULT_ATTR_COUNT; msg->attr_used = 0; return 0; } /** * radius_msg_new - Create a new RADIUS message * @code: Code for RADIUS header * @identifier: Identifier for RADIUS header * Returns: Context for RADIUS message or %NULL on failure * * The caller is responsible for freeing the returned data with * radius_msg_free(). */ struct radius_msg * radius_msg_new(u8 code, u8 identifier) { struct radius_msg *msg; msg = os_zalloc(sizeof(*msg)); if (msg == NULL) return NULL; msg->buf = wpabuf_alloc(RADIUS_DEFAULT_MSG_SIZE); if (msg->buf == NULL || radius_msg_initialize(msg)) { radius_msg_free(msg); return NULL; } msg->hdr = wpabuf_put(msg->buf, sizeof(struct radius_hdr)); radius_msg_set_hdr(msg, code, identifier); return msg; } /** * radius_msg_free - Free a RADIUS message * @msg: RADIUS message from radius_msg_new() or radius_msg_parse() */ void radius_msg_free(struct radius_msg *msg) { if (msg == NULL) return; wpabuf_free(msg->buf); os_free(msg->attr_pos); os_free(msg); } static const char *radius_code_string(u8 code) { switch (code) { case RADIUS_CODE_ACCESS_REQUEST: return "Access-Request"; case RADIUS_CODE_ACCESS_ACCEPT: return "Access-Accept"; case RADIUS_CODE_ACCESS_REJECT: return "Access-Reject"; case RADIUS_CODE_ACCOUNTING_REQUEST: return "Accounting-Request"; case RADIUS_CODE_ACCOUNTING_RESPONSE: return "Accounting-Response"; case RADIUS_CODE_ACCESS_CHALLENGE: return "Access-Challenge"; case RADIUS_CODE_STATUS_SERVER: return "Status-Server"; case RADIUS_CODE_STATUS_CLIENT: return "Status-Client"; case RADIUS_CODE_RESERVED: return "Reserved"; case RADIUS_CODE_DISCONNECT_REQUEST: return "Disconnect-Request"; case RADIUS_CODE_DISCONNECT_ACK: return "Disconnect-ACK"; case RADIUS_CODE_DISCONNECT_NAK: return "Disconnect-NAK"; case RADIUS_CODE_COA_REQUEST: return "CoA-Request"; case RADIUS_CODE_COA_ACK: return "CoA-ACK"; case RADIUS_CODE_COA_NAK: return "CoA-NAK"; default: return "?Unknown?"; } } struct radius_attr_type { u8 type; char *name; enum { RADIUS_ATTR_UNDIST, RADIUS_ATTR_TEXT, RADIUS_ATTR_IP, RADIUS_ATTR_HEXDUMP, RADIUS_ATTR_INT32, RADIUS_ATTR_IPV6 } data_type; }; static const struct radius_attr_type radius_attrs[] = { { RADIUS_ATTR_USER_NAME, "User-Name", RADIUS_ATTR_TEXT }, { RADIUS_ATTR_USER_PASSWORD, "User-Password", RADIUS_ATTR_UNDIST }, { RADIUS_ATTR_NAS_IP_ADDRESS, "NAS-IP-Address", RADIUS_ATTR_IP }, { RADIUS_ATTR_NAS_PORT, "NAS-Port", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_SERVICE_TYPE, "Service-Type", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_FRAMED_IP_ADDRESS, "Framed-IP-Address", RADIUS_ATTR_IP }, { RADIUS_ATTR_FRAMED_MTU, "Framed-MTU", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_REPLY_MESSAGE, "Reply-Message", RADIUS_ATTR_TEXT }, { RADIUS_ATTR_STATE, "State", RADIUS_ATTR_UNDIST }, { RADIUS_ATTR_CLASS, "Class", RADIUS_ATTR_UNDIST }, { RADIUS_ATTR_VENDOR_SPECIFIC, "Vendor-Specific", RADIUS_ATTR_UNDIST }, { RADIUS_ATTR_SESSION_TIMEOUT, "Session-Timeout", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_IDLE_TIMEOUT, "Idle-Timeout", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_TERMINATION_ACTION, "Termination-Action", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_CALLED_STATION_ID, "Called-Station-Id", RADIUS_ATTR_TEXT }, { RADIUS_ATTR_CALLING_STATION_ID, "Calling-Station-Id", RADIUS_ATTR_TEXT }, { RADIUS_ATTR_NAS_IDENTIFIER, "NAS-Identifier", RADIUS_ATTR_TEXT }, { RADIUS_ATTR_PROXY_STATE, "Proxy-State", RADIUS_ATTR_UNDIST }, { RADIUS_ATTR_ACCT_STATUS_TYPE, "Acct-Status-Type", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_ACCT_DELAY_TIME, "Acct-Delay-Time", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_ACCT_INPUT_OCTETS, "Acct-Input-Octets", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_ACCT_OUTPUT_OCTETS, "Acct-Output-Octets", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_ACCT_SESSION_ID, "Acct-Session-Id", RADIUS_ATTR_TEXT }, { RADIUS_ATTR_ACCT_AUTHENTIC, "Acct-Authentic", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_ACCT_SESSION_TIME, "Acct-Session-Time", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_ACCT_INPUT_PACKETS, "Acct-Input-Packets", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_ACCT_OUTPUT_PACKETS, "Acct-Output-Packets", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_ACCT_TERMINATE_CAUSE, "Acct-Terminate-Cause", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_ACCT_MULTI_SESSION_ID, "Acct-Multi-Session-Id", RADIUS_ATTR_TEXT }, { RADIUS_ATTR_ACCT_LINK_COUNT, "Acct-Link-Count", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_ACCT_INPUT_GIGAWORDS, "Acct-Input-Gigawords", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_ACCT_OUTPUT_GIGAWORDS, "Acct-Output-Gigawords", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_EVENT_TIMESTAMP, "Event-Timestamp", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_EGRESS_VLANID, "EGRESS-VLANID", RADIUS_ATTR_HEXDUMP }, { RADIUS_ATTR_NAS_PORT_TYPE, "NAS-Port-Type", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_TUNNEL_TYPE, "Tunnel-Type", RADIUS_ATTR_HEXDUMP }, { RADIUS_ATTR_TUNNEL_MEDIUM_TYPE, "Tunnel-Medium-Type", RADIUS_ATTR_HEXDUMP }, { RADIUS_ATTR_TUNNEL_PASSWORD, "Tunnel-Password", RADIUS_ATTR_UNDIST }, { RADIUS_ATTR_CONNECT_INFO, "Connect-Info", RADIUS_ATTR_TEXT }, { RADIUS_ATTR_EAP_MESSAGE, "EAP-Message", RADIUS_ATTR_UNDIST }, { RADIUS_ATTR_MESSAGE_AUTHENTICATOR, "Message-Authenticator", RADIUS_ATTR_UNDIST }, { RADIUS_ATTR_TUNNEL_PRIVATE_GROUP_ID, "Tunnel-Private-Group-Id", RADIUS_ATTR_HEXDUMP }, { RADIUS_ATTR_ACCT_INTERIM_INTERVAL, "Acct-Interim-Interval", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_CHARGEABLE_USER_IDENTITY, "Chargeable-User-Identity", RADIUS_ATTR_TEXT }, { RADIUS_ATTR_NAS_IPV6_ADDRESS, "NAS-IPv6-Address", RADIUS_ATTR_IPV6 }, { RADIUS_ATTR_ERROR_CAUSE, "Error-Cause", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_EAP_KEY_NAME, "EAP-Key-Name", RADIUS_ATTR_HEXDUMP }, { RADIUS_ATTR_OPERATOR_NAME, "Operator-Name", RADIUS_ATTR_TEXT }, { RADIUS_ATTR_LOCATION_INFO, "Location-Information", RADIUS_ATTR_HEXDUMP }, { RADIUS_ATTR_LOCATION_DATA, "Location-Data", RADIUS_ATTR_HEXDUMP }, { RADIUS_ATTR_BASIC_LOCATION_POLICY_RULES, "Basic-Location-Policy-Rules", RADIUS_ATTR_HEXDUMP }, { RADIUS_ATTR_EXTENDED_LOCATION_POLICY_RULES, "Extended-Location-Policy-Rules", RADIUS_ATTR_HEXDUMP }, { RADIUS_ATTR_LOCATION_CAPABLE, "Location-Capable", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_REQUESTED_LOCATION_INFO, "Requested-Location-Info", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_MOBILITY_DOMAIN_ID, "Mobility-Domain-Id", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_WLAN_HESSID, "WLAN-HESSID", RADIUS_ATTR_TEXT }, { RADIUS_ATTR_WLAN_REASON_CODE, "WLAN-Reason-Code", RADIUS_ATTR_INT32 }, { RADIUS_ATTR_WLAN_PAIRWISE_CIPHER, "WLAN-Pairwise-Cipher", RADIUS_ATTR_HEXDUMP }, { RADIUS_ATTR_WLAN_GROUP_CIPHER, "WLAN-Group-Cipher", RADIUS_ATTR_HEXDUMP }, { RADIUS_ATTR_WLAN_AKM_SUITE, "WLAN-AKM-Suite", RADIUS_ATTR_HEXDUMP }, { RADIUS_ATTR_WLAN_GROUP_MGMT_CIPHER, "WLAN-Group-Mgmt-Pairwise-Cipher", RADIUS_ATTR_HEXDUMP }, }; #define RADIUS_ATTRS ARRAY_SIZE(radius_attrs) static const struct radius_attr_type *radius_get_attr_type(u8 type) { size_t i; for (i = 0; i < RADIUS_ATTRS; i++) { if (type == radius_attrs[i].type) return &radius_attrs[i]; } return NULL; } static void radius_msg_dump_attr(struct radius_attr_hdr *hdr) { const struct radius_attr_type *attr; int len; unsigned char *pos; char buf[1000]; attr = radius_get_attr_type(hdr->type); wpa_printf(MSG_INFO, " Attribute %d (%s) length=%d", hdr->type, attr ? attr->name : "?Unknown?", hdr->length); if (attr == NULL || hdr->length < sizeof(struct radius_attr_hdr)) return; len = hdr->length - sizeof(struct radius_attr_hdr); pos = (unsigned char *) (hdr + 1); switch (attr->data_type) { case RADIUS_ATTR_TEXT: printf_encode(buf, sizeof(buf), pos, len); wpa_printf(MSG_INFO, " Value: '%s'", buf); break; case RADIUS_ATTR_IP: if (len == 4) { struct in_addr addr; os_memcpy(&addr, pos, 4); wpa_printf(MSG_INFO, " Value: %s", inet_ntoa(addr)); } else { wpa_printf(MSG_INFO, " Invalid IP address length %d", len); } break; #ifdef CONFIG_IPV6 case RADIUS_ATTR_IPV6: if (len == 16) { const char *atxt; struct in6_addr *addr = (struct in6_addr *) pos; atxt = inet_ntop(AF_INET6, addr, buf, sizeof(buf)); wpa_printf(MSG_INFO, " Value: %s", atxt ? atxt : "?"); } else { wpa_printf(MSG_INFO, " Invalid IPv6 address length %d", len); } break; #endif /* CONFIG_IPV6 */ case RADIUS_ATTR_HEXDUMP: case RADIUS_ATTR_UNDIST: wpa_snprintf_hex(buf, sizeof(buf), pos, len); wpa_printf(MSG_INFO, " Value: %s", buf); break; case RADIUS_ATTR_INT32: if (len == 4) wpa_printf(MSG_INFO, " Value: %u", WPA_GET_BE32(pos)); else wpa_printf(MSG_INFO, " Invalid INT32 length %d", len); break; default: break; } } void radius_msg_dump(struct radius_msg *msg) { size_t i; wpa_printf(MSG_INFO, "RADIUS message: code=%d (%s) identifier=%d length=%d", msg->hdr->code, radius_code_string(msg->hdr->code), msg->hdr->identifier, be_to_host16(msg->hdr->length)); for (i = 0; i < msg->attr_used; i++) { struct radius_attr_hdr *attr = radius_get_attr_hdr(msg, i); radius_msg_dump_attr(attr); } } int radius_msg_finish(struct radius_msg *msg, const u8 *secret, size_t secret_len) { if (secret) { u8 auth[MD5_MAC_LEN]; struct radius_attr_hdr *attr; os_memset(auth, 0, MD5_MAC_LEN); attr = radius_msg_add_attr(msg, RADIUS_ATTR_MESSAGE_AUTHENTICATOR, auth, MD5_MAC_LEN); if (attr == NULL) { wpa_printf(MSG_WARNING, "RADIUS: Could not add " "Message-Authenticator"); return -1; } msg->hdr->length = host_to_be16(wpabuf_len(msg->buf)); hmac_md5(secret, secret_len, wpabuf_head(msg->buf), wpabuf_len(msg->buf), (u8 *) (attr + 1)); } else msg->hdr->length = host_to_be16(wpabuf_len(msg->buf)); if (wpabuf_len(msg->buf) > 0xffff) { wpa_printf(MSG_WARNING, "RADIUS: Too long message (%lu)", (unsigned long) wpabuf_len(msg->buf)); return -1; } return 0; } int radius_msg_finish_srv(struct radius_msg *msg, const u8 *secret, size_t secret_len, const u8 *req_authenticator) { u8 auth[MD5_MAC_LEN]; struct radius_attr_hdr *attr; const u8 *addr[4]; size_t len[4]; os_memset(auth, 0, MD5_MAC_LEN); attr = radius_msg_add_attr(msg, RADIUS_ATTR_MESSAGE_AUTHENTICATOR, auth, MD5_MAC_LEN); if (attr == NULL) { wpa_printf(MSG_ERROR, "WARNING: Could not add Message-Authenticator"); return -1; } msg->hdr->length = host_to_be16(wpabuf_len(msg->buf)); os_memcpy(msg->hdr->authenticator, req_authenticator, sizeof(msg->hdr->authenticator)); hmac_md5(secret, secret_len, wpabuf_head(msg->buf), wpabuf_len(msg->buf), (u8 *) (attr + 1)); /* ResponseAuth = MD5(Code+ID+Length+RequestAuth+Attributes+Secret) */ addr[0] = (u8 *) msg->hdr; len[0] = 1 + 1 + 2; addr[1] = req_authenticator; len[1] = MD5_MAC_LEN; addr[2] = wpabuf_head_u8(msg->buf) + sizeof(struct radius_hdr); len[2] = wpabuf_len(msg->buf) - sizeof(struct radius_hdr); addr[3] = secret; len[3] = secret_len; md5_vector(4, addr, len, msg->hdr->authenticator); if (wpabuf_len(msg->buf) > 0xffff) { wpa_printf(MSG_WARNING, "RADIUS: Too long message (%lu)", (unsigned long) wpabuf_len(msg->buf)); return -1; } return 0; } int radius_msg_finish_das_resp(struct radius_msg *msg, const u8 *secret, size_t secret_len, const struct radius_hdr *req_hdr) { const u8 *addr[2]; size_t len[2]; u8 auth[MD5_MAC_LEN]; struct radius_attr_hdr *attr; os_memset(auth, 0, MD5_MAC_LEN); attr = radius_msg_add_attr(msg, RADIUS_ATTR_MESSAGE_AUTHENTICATOR, auth, MD5_MAC_LEN); if (attr == NULL) { wpa_printf(MSG_WARNING, "Could not add Message-Authenticator"); return -1; } msg->hdr->length = host_to_be16(wpabuf_len(msg->buf)); os_memcpy(msg->hdr->authenticator, req_hdr->authenticator, 16); hmac_md5(secret, secret_len, wpabuf_head(msg->buf), wpabuf_len(msg->buf), (u8 *) (attr + 1)); /* ResponseAuth = MD5(Code+ID+Length+RequestAuth+Attributes+Secret) */ addr[0] = wpabuf_head_u8(msg->buf); len[0] = wpabuf_len(msg->buf); addr[1] = secret; len[1] = secret_len; if (md5_vector(2, addr, len, msg->hdr->authenticator) < 0) return -1; if (wpabuf_len(msg->buf) > 0xffff) { wpa_printf(MSG_WARNING, "RADIUS: Too long message (%lu)", (unsigned long) wpabuf_len(msg->buf)); return -1; } return 0; } void radius_msg_finish_acct(struct radius_msg *msg, const u8 *secret, size_t secret_len) { const u8 *addr[2]; size_t len[2]; msg->hdr->length = host_to_be16(wpabuf_len(msg->buf)); os_memset(msg->hdr->authenticator, 0, MD5_MAC_LEN); addr[0] = wpabuf_head(msg->buf); len[0] = wpabuf_len(msg->buf); addr[1] = secret; len[1] = secret_len; md5_vector(2, addr, len, msg->hdr->authenticator); if (wpabuf_len(msg->buf) > 0xffff) { wpa_printf(MSG_WARNING, "RADIUS: Too long messages (%lu)", (unsigned long) wpabuf_len(msg->buf)); } } void radius_msg_finish_acct_resp(struct radius_msg *msg, const u8 *secret, size_t secret_len, const u8 *req_authenticator) { const u8 *addr[2]; size_t len[2]; msg->hdr->length = host_to_be16(wpabuf_len(msg->buf)); os_memcpy(msg->hdr->authenticator, req_authenticator, MD5_MAC_LEN); addr[0] = wpabuf_head(msg->buf); len[0] = wpabuf_len(msg->buf); addr[1] = secret; len[1] = secret_len; md5_vector(2, addr, len, msg->hdr->authenticator); if (wpabuf_len(msg->buf) > 0xffff) { wpa_printf(MSG_WARNING, "RADIUS: Too long messages (%lu)", (unsigned long) wpabuf_len(msg->buf)); } } int radius_msg_verify_acct_req(struct radius_msg *msg, const u8 *secret, size_t secret_len) { const u8 *addr[4]; size_t len[4]; u8 zero[MD5_MAC_LEN]; u8 hash[MD5_MAC_LEN]; os_memset(zero, 0, sizeof(zero)); addr[0] = (u8 *) msg->hdr; len[0] = sizeof(struct radius_hdr) - MD5_MAC_LEN; addr[1] = zero; len[1] = MD5_MAC_LEN; addr[2] = (u8 *) (msg->hdr + 1); len[2] = wpabuf_len(msg->buf) - sizeof(struct radius_hdr); addr[3] = secret; len[3] = secret_len; md5_vector(4, addr, len, hash); return os_memcmp_const(msg->hdr->authenticator, hash, MD5_MAC_LEN) != 0; } int radius_msg_verify_das_req(struct radius_msg *msg, const u8 *secret, size_t secret_len, int require_message_authenticator) { const u8 *addr[4]; size_t len[4]; u8 zero[MD5_MAC_LEN]; u8 hash[MD5_MAC_LEN]; u8 auth[MD5_MAC_LEN], orig[MD5_MAC_LEN]; u8 orig_authenticator[16]; struct radius_attr_hdr *attr = NULL, *tmp; size_t i; os_memset(zero, 0, sizeof(zero)); addr[0] = (u8 *) msg->hdr; len[0] = sizeof(struct radius_hdr) - MD5_MAC_LEN; addr[1] = zero; len[1] = MD5_MAC_LEN; addr[2] = (u8 *) (msg->hdr + 1); len[2] = wpabuf_len(msg->buf) - sizeof(struct radius_hdr); addr[3] = secret; len[3] = secret_len; md5_vector(4, addr, len, hash); if (os_memcmp_const(msg->hdr->authenticator, hash, MD5_MAC_LEN) != 0) return 1; for (i = 0; i < msg->attr_used; i++) { tmp = radius_get_attr_hdr(msg, i); if (tmp->type == RADIUS_ATTR_MESSAGE_AUTHENTICATOR) { if (attr != NULL) { wpa_printf(MSG_WARNING, "Multiple " "Message-Authenticator attributes " "in RADIUS message"); return 1; } attr = tmp; } } if (attr == NULL) { if (require_message_authenticator) { wpa_printf(MSG_WARNING, "Missing Message-Authenticator attribute in RADIUS message"); return 1; } return 0; } os_memcpy(orig, attr + 1, MD5_MAC_LEN); os_memset(attr + 1, 0, MD5_MAC_LEN); os_memcpy(orig_authenticator, msg->hdr->authenticator, sizeof(orig_authenticator)); os_memset(msg->hdr->authenticator, 0, sizeof(msg->hdr->authenticator)); hmac_md5(secret, secret_len, wpabuf_head(msg->buf), wpabuf_len(msg->buf), auth); os_memcpy(attr + 1, orig, MD5_MAC_LEN); os_memcpy(msg->hdr->authenticator, orig_authenticator, sizeof(orig_authenticator)); return os_memcmp_const(orig, auth, MD5_MAC_LEN) != 0; } static int radius_msg_add_attr_to_array(struct radius_msg *msg, struct radius_attr_hdr *attr) { if (msg->attr_used >= msg->attr_size) { size_t *nattr_pos; int nlen = msg->attr_size * 2; nattr_pos = os_realloc_array(msg->attr_pos, nlen, sizeof(*msg->attr_pos)); if (nattr_pos == NULL) return -1; msg->attr_pos = nattr_pos; msg->attr_size = nlen; } msg->attr_pos[msg->attr_used++] = (unsigned char *) attr - wpabuf_head_u8(msg->buf); return 0; } struct radius_attr_hdr *radius_msg_add_attr(struct radius_msg *msg, u8 type, const u8 *data, size_t data_len) { size_t buf_needed; struct radius_attr_hdr *attr; if (TEST_FAIL()) return NULL; if (data_len > RADIUS_MAX_ATTR_LEN) { wpa_printf(MSG_ERROR, "radius_msg_add_attr: too long attribute (%lu bytes)", (unsigned long) data_len); return NULL; } buf_needed = sizeof(*attr) + data_len; if (wpabuf_tailroom(msg->buf) < buf_needed) { /* allocate more space for message buffer */ if (wpabuf_resize(&msg->buf, buf_needed) < 0) return NULL; msg->hdr = wpabuf_mhead(msg->buf); } attr = wpabuf_put(msg->buf, sizeof(struct radius_attr_hdr)); attr->type = type; attr->length = sizeof(*attr) + data_len; wpabuf_put_data(msg->buf, data, data_len); if (radius_msg_add_attr_to_array(msg, attr)) return NULL; return attr; } /** * radius_msg_parse - Parse a RADIUS message * @data: RADIUS message to be parsed * @len: Length of data buffer in octets * Returns: Parsed RADIUS message or %NULL on failure * * This parses a RADIUS message and makes a copy of its data. The caller is * responsible for freeing the returned data with radius_msg_free(). */ struct radius_msg * radius_msg_parse(const u8 *data, size_t len) { struct radius_msg *msg; struct radius_hdr *hdr; struct radius_attr_hdr *attr; size_t msg_len; unsigned char *pos, *end; if (data == NULL || len < sizeof(*hdr)) return NULL; hdr = (struct radius_hdr *) data; msg_len = be_to_host16(hdr->length); if (msg_len < sizeof(*hdr) || msg_len > len) { wpa_printf(MSG_INFO, "RADIUS: Invalid message length"); return NULL; } if (msg_len < len) { wpa_printf(MSG_DEBUG, "RADIUS: Ignored %lu extra bytes after " "RADIUS message", (unsigned long) len - msg_len); } msg = os_zalloc(sizeof(*msg)); if (msg == NULL) return NULL; msg->buf = wpabuf_alloc_copy(data, msg_len); if (msg->buf == NULL || radius_msg_initialize(msg)) { radius_msg_free(msg); return NULL; } msg->hdr = wpabuf_mhead(msg->buf); /* parse attributes */ pos = wpabuf_mhead_u8(msg->buf) + sizeof(struct radius_hdr); end = wpabuf_mhead_u8(msg->buf) + wpabuf_len(msg->buf); while (pos < end) { if ((size_t) (end - pos) < sizeof(*attr)) goto fail; attr = (struct radius_attr_hdr *) pos; if (attr->length > end - pos || attr->length < sizeof(*attr)) goto fail; /* TODO: check that attr->length is suitable for attr->type */ if (radius_msg_add_attr_to_array(msg, attr)) goto fail; pos += attr->length; } return msg; fail: radius_msg_free(msg); return NULL; } int radius_msg_add_eap(struct radius_msg *msg, const u8 *data, size_t data_len) { const u8 *pos = data; size_t left = data_len; while (left > 0) { int len; if (left > RADIUS_MAX_ATTR_LEN) len = RADIUS_MAX_ATTR_LEN; else len = left; if (!radius_msg_add_attr(msg, RADIUS_ATTR_EAP_MESSAGE, pos, len)) return 0; pos += len; left -= len; } return 1; } struct wpabuf * radius_msg_get_eap(struct radius_msg *msg) { struct wpabuf *eap; size_t len, i; struct radius_attr_hdr *attr; if (msg == NULL) return NULL; len = 0; for (i = 0; i < msg->attr_used; i++) { attr = radius_get_attr_hdr(msg, i); if (attr->type == RADIUS_ATTR_EAP_MESSAGE && attr->length > sizeof(struct radius_attr_hdr)) len += attr->length - sizeof(struct radius_attr_hdr); } if (len == 0) return NULL; eap = wpabuf_alloc(len); if (eap == NULL) return NULL; for (i = 0; i < msg->attr_used; i++) { attr = radius_get_attr_hdr(msg, i); if (attr->type == RADIUS_ATTR_EAP_MESSAGE && attr->length > sizeof(struct radius_attr_hdr)) { int flen = attr->length - sizeof(*attr); wpabuf_put_data(eap, attr + 1, flen); } } return eap; } int radius_msg_verify_msg_auth(struct radius_msg *msg, const u8 *secret, size_t secret_len, const u8 *req_auth) { u8 auth[MD5_MAC_LEN], orig[MD5_MAC_LEN]; u8 orig_authenticator[16]; struct radius_attr_hdr *attr = NULL, *tmp; size_t i; for (i = 0; i < msg->attr_used; i++) { tmp = radius_get_attr_hdr(msg, i); if (tmp->type == RADIUS_ATTR_MESSAGE_AUTHENTICATOR) { if (attr != NULL) { wpa_printf(MSG_INFO, "Multiple Message-Authenticator attributes in RADIUS message"); return 1; } attr = tmp; } } if (attr == NULL) { wpa_printf(MSG_INFO, "No Message-Authenticator attribute found"); return 1; } os_memcpy(orig, attr + 1, MD5_MAC_LEN); os_memset(attr + 1, 0, MD5_MAC_LEN); if (req_auth) { os_memcpy(orig_authenticator, msg->hdr->authenticator, sizeof(orig_authenticator)); os_memcpy(msg->hdr->authenticator, req_auth, sizeof(msg->hdr->authenticator)); } if (hmac_md5(secret, secret_len, wpabuf_head(msg->buf), wpabuf_len(msg->buf), auth) < 0) return 1; os_memcpy(attr + 1, orig, MD5_MAC_LEN); if (req_auth) { os_memcpy(msg->hdr->authenticator, orig_authenticator, sizeof(orig_authenticator)); } if (os_memcmp_const(orig, auth, MD5_MAC_LEN) != 0) { wpa_printf(MSG_INFO, "Invalid Message-Authenticator!"); return 1; } return 0; } int radius_msg_verify(struct radius_msg *msg, const u8 *secret, size_t secret_len, struct radius_msg *sent_msg, int auth) { const u8 *addr[4]; size_t len[4]; u8 hash[MD5_MAC_LEN]; if (sent_msg == NULL) { wpa_printf(MSG_INFO, "No matching Access-Request message found"); return 1; } if (auth && radius_msg_verify_msg_auth(msg, secret, secret_len, sent_msg->hdr->authenticator)) { return 1; } /* ResponseAuth = MD5(Code+ID+Length+RequestAuth+Attributes+Secret) */ addr[0] = (u8 *) msg->hdr; len[0] = 1 + 1 + 2; addr[1] = sent_msg->hdr->authenticator; len[1] = MD5_MAC_LEN; addr[2] = wpabuf_head_u8(msg->buf) + sizeof(struct radius_hdr); len[2] = wpabuf_len(msg->buf) - sizeof(struct radius_hdr); addr[3] = secret; len[3] = secret_len; if (md5_vector(4, addr, len, hash) < 0 || os_memcmp_const(hash, msg->hdr->authenticator, MD5_MAC_LEN) != 0) { wpa_printf(MSG_INFO, "Response Authenticator invalid!"); return 1; } return 0; } int radius_msg_copy_attr(struct radius_msg *dst, struct radius_msg *src, u8 type) { struct radius_attr_hdr *attr; size_t i; int count = 0; for (i = 0; i < src->attr_used; i++) { attr = radius_get_attr_hdr(src, i); if (attr->type == type && attr->length >= sizeof(*attr)) { if (!radius_msg_add_attr(dst, type, (u8 *) (attr + 1), attr->length - sizeof(*attr))) return -1; count++; } } return count; } /* Create Request Authenticator. The value should be unique over the lifetime * of the shared secret between authenticator and authentication server. */ int radius_msg_make_authenticator(struct radius_msg *msg) { return os_get_random((u8 *) &msg->hdr->authenticator, sizeof(msg->hdr->authenticator)); } /* Get Vendor-specific RADIUS Attribute from a parsed RADIUS message. * Returns the Attribute payload and sets alen to indicate the length of the * payload if a vendor attribute with subtype is found, otherwise returns NULL. * The returned payload is allocated with os_malloc() and caller must free it * by calling os_free(). */ static u8 *radius_msg_get_vendor_attr(struct radius_msg *msg, u32 vendor, u8 subtype, size_t *alen) { u8 *data, *pos; size_t i, len; if (msg == NULL) return NULL; for (i = 0; i < msg->attr_used; i++) { struct radius_attr_hdr *attr = radius_get_attr_hdr(msg, i); size_t left; u32 vendor_id; struct radius_attr_vendor *vhdr; if (attr->type != RADIUS_ATTR_VENDOR_SPECIFIC || attr->length < sizeof(*attr)) continue; left = attr->length - sizeof(*attr); if (left < 4) continue; pos = (u8 *) (attr + 1); os_memcpy(&vendor_id, pos, 4); pos += 4; left -= 4; if (ntohl(vendor_id) != vendor) continue; while (left >= sizeof(*vhdr)) { vhdr = (struct radius_attr_vendor *) pos; if (vhdr->vendor_length > left || vhdr->vendor_length < sizeof(*vhdr)) { break; } if (vhdr->vendor_type != subtype) { pos += vhdr->vendor_length; left -= vhdr->vendor_length; continue; } len = vhdr->vendor_length - sizeof(*vhdr); data = os_memdup(pos + sizeof(*vhdr), len); if (data == NULL) return NULL; if (alen) *alen = len; return data; } } return NULL; } static u8 * decrypt_ms_key(const u8 *key, size_t len, const u8 *req_authenticator, const u8 *secret, size_t secret_len, size_t *reslen) { u8 *plain, *ppos, *res; const u8 *pos; size_t left, plen; u8 hash[MD5_MAC_LEN]; int i, first = 1; const u8 *addr[3]; size_t elen[3]; /* key: 16-bit salt followed by encrypted key info */ if (len < 2 + 16) { wpa_printf(MSG_DEBUG, "RADIUS: %s: Len is too small: %d", __func__, (int) len); return NULL; } pos = key + 2; left = len - 2; if (left % 16) { wpa_printf(MSG_INFO, "RADIUS: Invalid ms key len %lu", (unsigned long) left); return NULL; } plen = left; ppos = plain = os_malloc(plen); if (plain == NULL) return NULL; plain[0] = 0; while (left > 0) { /* b(1) = MD5(Secret + Request-Authenticator + Salt) * b(i) = MD5(Secret + c(i - 1)) for i > 1 */ addr[0] = secret; elen[0] = secret_len; if (first) { addr[1] = req_authenticator; elen[1] = MD5_MAC_LEN; addr[2] = key; elen[2] = 2; /* Salt */ } else { addr[1] = pos - MD5_MAC_LEN; elen[1] = MD5_MAC_LEN; } if (md5_vector(first ? 3 : 2, addr, elen, hash) < 0) { os_free(plain); return NULL; } first = 0; for (i = 0; i < MD5_MAC_LEN; i++) *ppos++ = *pos++ ^ hash[i]; left -= MD5_MAC_LEN; } if (plain[0] == 0 || plain[0] > plen - 1) { wpa_printf(MSG_INFO, "RADIUS: Failed to decrypt MPPE key"); os_free(plain); return NULL; } res = os_memdup(plain + 1, plain[0]); if (res == NULL) { os_free(plain); return NULL; } if (reslen) *reslen = plain[0]; os_free(plain); return res; } static void encrypt_ms_key(const u8 *key, size_t key_len, u16 salt, const u8 *req_authenticator, const u8 *secret, size_t secret_len, u8 *ebuf, size_t *elen) { int i, len, first = 1; u8 hash[MD5_MAC_LEN], saltbuf[2], *pos; const u8 *addr[3]; size_t _len[3]; WPA_PUT_BE16(saltbuf, salt); len = 1 + key_len; if (len & 0x0f) { len = (len & 0xf0) + 16; } os_memset(ebuf, 0, len); ebuf[0] = key_len; os_memcpy(ebuf + 1, key, key_len); *elen = len; pos = ebuf; while (len > 0) { /* b(1) = MD5(Secret + Request-Authenticator + Salt) * b(i) = MD5(Secret + c(i - 1)) for i > 1 */ addr[0] = secret; _len[0] = secret_len; if (first) { addr[1] = req_authenticator; _len[1] = MD5_MAC_LEN; addr[2] = saltbuf; _len[2] = sizeof(saltbuf); } else { addr[1] = pos - MD5_MAC_LEN; _len[1] = MD5_MAC_LEN; } md5_vector(first ? 3 : 2, addr, _len, hash); first = 0; for (i = 0; i < MD5_MAC_LEN; i++) *pos++ ^= hash[i]; len -= MD5_MAC_LEN; } } struct radius_ms_mppe_keys * radius_msg_get_ms_keys(struct radius_msg *msg, struct radius_msg *sent_msg, const u8 *secret, size_t secret_len) { u8 *key; size_t keylen; struct radius_ms_mppe_keys *keys; if (msg == NULL || sent_msg == NULL) return NULL; keys = os_zalloc(sizeof(*keys)); if (keys == NULL) return NULL; key = radius_msg_get_vendor_attr(msg, RADIUS_VENDOR_ID_MICROSOFT, RADIUS_VENDOR_ATTR_MS_MPPE_SEND_KEY, &keylen); if (key) { keys->send = decrypt_ms_key(key, keylen, sent_msg->hdr->authenticator, secret, secret_len, &keys->send_len); if (!keys->send) { wpa_printf(MSG_DEBUG, "RADIUS: Failed to decrypt send key"); } os_free(key); } key = radius_msg_get_vendor_attr(msg, RADIUS_VENDOR_ID_MICROSOFT, RADIUS_VENDOR_ATTR_MS_MPPE_RECV_KEY, &keylen); if (key) { keys->recv = decrypt_ms_key(key, keylen, sent_msg->hdr->authenticator, secret, secret_len, &keys->recv_len); if (!keys->recv) { wpa_printf(MSG_DEBUG, "RADIUS: Failed to decrypt recv key"); } os_free(key); } return keys; } struct radius_ms_mppe_keys * radius_msg_get_cisco_keys(struct radius_msg *msg, struct radius_msg *sent_msg, const u8 *secret, size_t secret_len) { u8 *key; size_t keylen; struct radius_ms_mppe_keys *keys; if (msg == NULL || sent_msg == NULL) return NULL; keys = os_zalloc(sizeof(*keys)); if (keys == NULL) return NULL; key = radius_msg_get_vendor_attr(msg, RADIUS_VENDOR_ID_CISCO, RADIUS_CISCO_AV_PAIR, &keylen); if (key && keylen == 51 && os_memcmp(key, "leap:session-key=", 17) == 0) { keys->recv = decrypt_ms_key(key + 17, keylen - 17, sent_msg->hdr->authenticator, secret, secret_len, &keys->recv_len); } os_free(key); return keys; } int radius_msg_add_mppe_keys(struct radius_msg *msg, const u8 *req_authenticator, const u8 *secret, size_t secret_len, const u8 *send_key, size_t send_key_len, const u8 *recv_key, size_t recv_key_len) { struct radius_attr_hdr *attr; u32 vendor_id = htonl(RADIUS_VENDOR_ID_MICROSOFT); u8 *buf; struct radius_attr_vendor *vhdr; u8 *pos; size_t elen; int hlen; u16 salt; hlen = sizeof(vendor_id) + sizeof(*vhdr) + 2; /* MS-MPPE-Send-Key */ buf = os_malloc(hlen + send_key_len + 16); if (buf == NULL) { return 0; } pos = buf; os_memcpy(pos, &vendor_id, sizeof(vendor_id)); pos += sizeof(vendor_id); vhdr = (struct radius_attr_vendor *) pos; vhdr->vendor_type = RADIUS_VENDOR_ATTR_MS_MPPE_SEND_KEY; pos = (u8 *) (vhdr + 1); if (os_get_random((u8 *) &salt, sizeof(salt)) < 0) { os_free(buf); return 0; } salt |= 0x8000; WPA_PUT_BE16(pos, salt); pos += 2; encrypt_ms_key(send_key, send_key_len, salt, req_authenticator, secret, secret_len, pos, &elen); vhdr->vendor_length = hlen + elen - sizeof(vendor_id); attr = radius_msg_add_attr(msg, RADIUS_ATTR_VENDOR_SPECIFIC, buf, hlen + elen); os_free(buf); if (attr == NULL) { return 0; } /* MS-MPPE-Recv-Key */ buf = os_malloc(hlen + recv_key_len + 16); if (buf == NULL) { return 0; } pos = buf; os_memcpy(pos, &vendor_id, sizeof(vendor_id)); pos += sizeof(vendor_id); vhdr = (struct radius_attr_vendor *) pos; vhdr->vendor_type = RADIUS_VENDOR_ATTR_MS_MPPE_RECV_KEY; pos = (u8 *) (vhdr + 1); salt ^= 1; WPA_PUT_BE16(pos, salt); pos += 2; encrypt_ms_key(recv_key, recv_key_len, salt, req_authenticator, secret, secret_len, pos, &elen); vhdr->vendor_length = hlen + elen - sizeof(vendor_id); attr = radius_msg_add_attr(msg, RADIUS_ATTR_VENDOR_SPECIFIC, buf, hlen + elen); os_free(buf); if (attr == NULL) { return 0; } return 1; } int radius_msg_add_wfa(struct radius_msg *msg, u8 subtype, const u8 *data, size_t len) { struct radius_attr_hdr *attr; u8 *buf, *pos; size_t alen; alen = 4 + 2 + len; buf = os_malloc(alen); if (buf == NULL) return 0; pos = buf; WPA_PUT_BE32(pos, RADIUS_VENDOR_ID_WFA); pos += 4; *pos++ = subtype; *pos++ = 2 + len; os_memcpy(pos, data, len); attr = radius_msg_add_attr(msg, RADIUS_ATTR_VENDOR_SPECIFIC, buf, alen); os_free(buf); if (attr == NULL) return 0; return 1; } int radius_user_password_hide(struct radius_msg *msg, const u8 *data, size_t data_len, const u8 *secret, size_t secret_len, u8 *buf, size_t buf_len) { size_t padlen, i, pos; const u8 *addr[2]; size_t len[2]; u8 hash[16]; if (data_len + 16 > buf_len) return -1; os_memcpy(buf, data, data_len); padlen = data_len % 16; if (padlen && data_len < buf_len) { padlen = 16 - padlen; os_memset(buf + data_len, 0, padlen); buf_len = data_len + padlen; } else { buf_len = data_len; } addr[0] = secret; len[0] = secret_len; addr[1] = msg->hdr->authenticator; len[1] = 16; md5_vector(2, addr, len, hash); for (i = 0; i < 16; i++) buf[i] ^= hash[i]; pos = 16; while (pos < buf_len) { addr[0] = secret; len[0] = secret_len; addr[1] = &buf[pos - 16]; len[1] = 16; md5_vector(2, addr, len, hash); for (i = 0; i < 16; i++) buf[pos + i] ^= hash[i]; pos += 16; } return buf_len; } /* Add User-Password attribute to a RADIUS message and encrypt it as specified * in RFC 2865, Chap. 5.2 */ struct radius_attr_hdr * radius_msg_add_attr_user_password(struct radius_msg *msg, const u8 *data, size_t data_len, const u8 *secret, size_t secret_len) { u8 buf[128]; int res; res = radius_user_password_hide(msg, data, data_len, secret, secret_len, buf, sizeof(buf)); if (res < 0) return NULL; return radius_msg_add_attr(msg, RADIUS_ATTR_USER_PASSWORD, buf, res); } int radius_msg_get_attr(struct radius_msg *msg, u8 type, u8 *buf, size_t len) { struct radius_attr_hdr *attr = NULL, *tmp; size_t i, dlen; for (i = 0; i < msg->attr_used; i++) { tmp = radius_get_attr_hdr(msg, i); if (tmp->type == type) { attr = tmp; break; } } if (!attr || attr->length < sizeof(*attr)) return -1; dlen = attr->length - sizeof(*attr); if (buf) os_memcpy(buf, (attr + 1), dlen > len ? len : dlen); return dlen; } int radius_msg_get_attr_ptr(struct radius_msg *msg, u8 type, u8 **buf, size_t *len, const u8 *start) { size_t i; struct radius_attr_hdr *attr = NULL, *tmp; for (i = 0; i < msg->attr_used; i++) { tmp = radius_get_attr_hdr(msg, i); if (tmp->type == type && (start == NULL || (u8 *) tmp > start)) { attr = tmp; break; } } if (!attr || attr->length < sizeof(*attr)) return -1; *buf = (u8 *) (attr + 1); *len = attr->length - sizeof(*attr); return 0; } int radius_msg_count_attr(struct radius_msg *msg, u8 type, int min_len) { size_t i; int count; for (count = 0, i = 0; i < msg->attr_used; i++) { struct radius_attr_hdr *attr = radius_get_attr_hdr(msg, i); if (attr->type == type && attr->length >= sizeof(struct radius_attr_hdr) + min_len) count++; } return count; } struct radius_tunnel_attrs { int tag_used; int type; /* Tunnel-Type */ int medium_type; /* Tunnel-Medium-Type */ int vlanid; }; static int cmp_int(const void *a, const void *b) { int x, y; x = *((int *) a); y = *((int *) b); return (x - y); } /** * radius_msg_get_vlanid - Parse RADIUS attributes for VLAN tunnel information * The k tagged vlans found are sorted by vlan_id and stored in the first k * items of tagged. * * @msg: RADIUS message * @untagged: Pointer to store untagged vid * @numtagged: Size of tagged * @tagged: Pointer to store tagged list * * Returns: 0 if neither tagged nor untagged configuration is found, 1 otherwise */ int radius_msg_get_vlanid(struct radius_msg *msg, int *untagged, int numtagged, int *tagged) { struct radius_tunnel_attrs tunnel[RADIUS_TUNNEL_TAGS], *tun; size_t i; struct radius_attr_hdr *attr = NULL; const u8 *data; char buf[10]; size_t dlen; int j, taggedidx = 0, vlan_id; os_memset(&tunnel, 0, sizeof(tunnel)); for (j = 0; j < numtagged; j++) tagged[j] = 0; *untagged = 0; for (i = 0; i < msg->attr_used; i++) { attr = radius_get_attr_hdr(msg, i); if (attr->length < sizeof(*attr)) return -1; data = (const u8 *) (attr + 1); dlen = attr->length - sizeof(*attr); if (attr->length < 3) continue; if (data[0] >= RADIUS_TUNNEL_TAGS) tun = &tunnel[0]; else tun = &tunnel[data[0]]; switch (attr->type) { case RADIUS_ATTR_TUNNEL_TYPE: if (attr->length != 6) break; tun->tag_used++; tun->type = WPA_GET_BE24(data + 1); break; case RADIUS_ATTR_TUNNEL_MEDIUM_TYPE: if (attr->length != 6) break; tun->tag_used++; tun->medium_type = WPA_GET_BE24(data + 1); break; case RADIUS_ATTR_TUNNEL_PRIVATE_GROUP_ID: if (data[0] < RADIUS_TUNNEL_TAGS) { data++; dlen--; } if (dlen >= sizeof(buf)) break; os_memcpy(buf, data, dlen); buf[dlen] = '\0'; vlan_id = atoi(buf); if (vlan_id <= 0) break; tun->tag_used++; tun->vlanid = vlan_id; break; case RADIUS_ATTR_EGRESS_VLANID: /* RFC 4675 */ if (attr->length != 6) break; vlan_id = WPA_GET_BE24(data + 1); if (vlan_id <= 0) break; if (data[0] == 0x32) *untagged = vlan_id; else if (data[0] == 0x31 && tagged && taggedidx < numtagged) tagged[taggedidx++] = vlan_id; break; } } /* Use tunnel with the lowest tag for untagged VLAN id */ for (i = 0; i < RADIUS_TUNNEL_TAGS; i++) { tun = &tunnel[i]; if (tun->tag_used && tun->type == RADIUS_TUNNEL_TYPE_VLAN && tun->medium_type == RADIUS_TUNNEL_MEDIUM_TYPE_802 && tun->vlanid > 0) { *untagged = tun->vlanid; break; } } if (taggedidx) qsort(tagged, taggedidx, sizeof(int), cmp_int); if (*untagged > 0 || taggedidx) return 1; return 0; } /** * radius_msg_get_tunnel_password - Parse RADIUS attribute Tunnel-Password * @msg: Received RADIUS message * @keylen: Length of returned password * @secret: RADIUS shared secret * @secret_len: Length of secret * @sent_msg: Sent RADIUS message * @n: Number of password attribute to return (starting with 0) * Returns: Pointer to n-th password (free with os_free) or %NULL */ char * radius_msg_get_tunnel_password(struct radius_msg *msg, int *keylen, const u8 *secret, size_t secret_len, struct radius_msg *sent_msg, size_t n) { u8 *buf = NULL; size_t buflen; const u8 *salt; u8 *str; const u8 *addr[3]; size_t len[3]; u8 hash[16]; u8 *pos; size_t i, j = 0; struct radius_attr_hdr *attr; const u8 *data; size_t dlen; const u8 *fdata = NULL; /* points to found item */ size_t fdlen = -1; char *ret = NULL; /* find n-th valid Tunnel-Password attribute */ for (i = 0; i < msg->attr_used; i++) { attr = radius_get_attr_hdr(msg, i); if (attr == NULL || attr->type != RADIUS_ATTR_TUNNEL_PASSWORD) { continue; } if (attr->length <= 5) continue; data = (const u8 *) (attr + 1); dlen = attr->length - sizeof(*attr); if (dlen <= 3 || dlen % 16 != 3) continue; j++; if (j <= n) continue; fdata = data; fdlen = dlen; break; } if (fdata == NULL) goto out; /* alloc writable memory for decryption */ buf = os_memdup(fdata, fdlen); if (buf == NULL) goto out; buflen = fdlen; /* init pointers */ salt = buf + 1; str = buf + 3; /* decrypt blocks */ pos = buf + buflen - 16; /* last block */ while (pos >= str + 16) { /* all but the first block */ addr[0] = secret; len[0] = secret_len; addr[1] = pos - 16; len[1] = 16; md5_vector(2, addr, len, hash); for (i = 0; i < 16; i++) pos[i] ^= hash[i]; pos -= 16; } /* decrypt first block */ if (str != pos) goto out; addr[0] = secret; len[0] = secret_len; addr[1] = sent_msg->hdr->authenticator; len[1] = 16; addr[2] = salt; len[2] = 2; md5_vector(3, addr, len, hash); for (i = 0; i < 16; i++) pos[i] ^= hash[i]; /* derive plaintext length from first subfield */ *keylen = (unsigned char) str[0]; if ((u8 *) (str + *keylen) >= (u8 *) (buf + buflen)) { /* decryption error - invalid key length */ goto out; } if (*keylen == 0) { /* empty password */ goto out; } /* copy passphrase into new buffer */ ret = os_malloc(*keylen); if (ret) os_memcpy(ret, str + 1, *keylen); out: /* return new buffer */ os_free(buf); return ret; } void radius_free_class(struct radius_class_data *c) { size_t i; if (c == NULL) return; for (i = 0; i < c->count; i++) os_free(c->attr[i].data); os_free(c->attr); c->attr = NULL; c->count = 0; } int radius_copy_class(struct radius_class_data *dst, const struct radius_class_data *src) { size_t i; if (src->attr == NULL) return 0; dst->attr = os_calloc(src->count, sizeof(struct radius_attr_data)); if (dst->attr == NULL) return -1; dst->count = 0; for (i = 0; i < src->count; i++) { dst->attr[i].data = os_memdup(src->attr[i].data, src->attr[i].len); if (dst->attr[i].data == NULL) break; dst->count++; dst->attr[i].len = src->attr[i].len; } return 0; } u8 radius_msg_find_unlisted_attr(struct radius_msg *msg, u8 *attrs) { size_t i, j; struct radius_attr_hdr *attr; for (i = 0; i < msg->attr_used; i++) { attr = radius_get_attr_hdr(msg, i); for (j = 0; attrs[j]; j++) { if (attr->type == attrs[j]) break; } if (attrs[j] == 0) return attr->type; /* unlisted attr */ } return 0; } int radius_gen_session_id(u8 *id, size_t len) { /* * Acct-Session-Id and Acct-Multi-Session-Id should be globally and * temporarily unique. A high quality random number is required * therefore. This could be be improved by switching to a GUID. */ return os_get_random(id, len); }