1 /* $NetBSD: chap-new.h,v 1.5 2021/01/09 16:39:28 christos Exp $ */ 2 3 /* 4 * chap-new.c - New CHAP implementation. 5 * 6 * Copyright (c) 2003 Paul Mackerras. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 15 * 2. The name(s) of the authors of this software must not be used to 16 * endorse or promote products derived from this software without 17 * prior written permission. 18 * 19 * 3. Redistributions of any form whatsoever must retain the following 20 * acknowledgment: 21 * "This product includes software developed by Paul Mackerras 22 * <paulus@samba.org>". 23 * 24 * THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO 25 * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY 26 * AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY 27 * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 28 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN 29 * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING 30 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 31 */ 32 33 /* 34 * CHAP packets begin with a standard header with code, id, len (2 bytes). 35 */ 36 #define CHAP_HDRLEN 4 37 38 /* 39 * Values for the code field. 40 */ 41 #define CHAP_CHALLENGE 1 42 #define CHAP_RESPONSE 2 43 #define CHAP_SUCCESS 3 44 #define CHAP_FAILURE 4 45 46 /* 47 * CHAP digest codes. 48 */ 49 #define CHAP_MD5 5 50 #define CHAP_MICROSOFT 0x80 51 #define CHAP_MICROSOFT_V2 0x81 52 53 /* 54 * Semi-arbitrary limits on challenge and response fields. 55 */ 56 #define MAX_CHALLENGE_LEN 64 57 #define MAX_RESPONSE_LEN 64 58 59 /* bitmask of supported algorithms */ 60 #define MDTYPE_MICROSOFT_V2 0x1 61 #define MDTYPE_MICROSOFT 0x2 62 #define MDTYPE_MD5 0x4 63 #define MDTYPE_NONE 0 64 65 /* hashes supported by this instance of pppd */ 66 extern int chap_mdtype_all; 67 68 /* Return the digest alg. ID for the most preferred digest type. */ 69 #define CHAP_DIGEST(mdtype) \ 70 ((mdtype) & MDTYPE_MD5)? CHAP_MD5: \ 71 ((mdtype) & MDTYPE_MICROSOFT_V2)? CHAP_MICROSOFT_V2: \ 72 ((mdtype) & MDTYPE_MICROSOFT)? CHAP_MICROSOFT: \ 73 0 74 75 /* Return the bit flag (lsb set) for our most preferred digest type. */ 76 #define CHAP_MDTYPE(mdtype) ((mdtype) ^ ((mdtype) - 1)) & (mdtype) 77 78 /* Return the bit flag for a given digest algorithm ID. */ 79 #define CHAP_MDTYPE_D(digest) \ 80 ((digest) == CHAP_MICROSOFT_V2)? MDTYPE_MICROSOFT_V2: \ 81 ((digest) == CHAP_MICROSOFT)? MDTYPE_MICROSOFT: \ 82 ((digest) == CHAP_MD5)? MDTYPE_MD5: \ 83 0 84 85 /* Can we do the requested digest? */ 86 #define CHAP_CANDIGEST(mdtype, digest) \ 87 ((digest) == CHAP_MICROSOFT_V2)? (mdtype) & MDTYPE_MICROSOFT_V2: \ 88 ((digest) == CHAP_MICROSOFT)? (mdtype) & MDTYPE_MICROSOFT: \ 89 ((digest) == CHAP_MD5)? (mdtype) & MDTYPE_MD5: \ 90 0 91 92 /* 93 * The code for each digest type has to supply one of these. 94 */ 95 struct chap_digest_type { 96 int code; 97 98 /* 99 * Note: challenge and response arguments below are formatted as 100 * a length byte followed by the actual challenge/response data. 101 */ 102 void (*generate_challenge)(unsigned char *challenge); 103 int (*verify_response)(int id, char *name, 104 unsigned char *secret, int secret_len, 105 unsigned char *challenge, unsigned char *response, 106 char *message, int message_space); 107 void (*make_response)(unsigned char *response, int id, char *our_name, 108 unsigned char *challenge, char *secret, int secret_len, 109 unsigned char *priv); 110 int (*check_success)(int id, unsigned char *pkt, int len); 111 void (*handle_failure)(unsigned char *pkt, int len); 112 113 struct chap_digest_type *next; 114 }; 115 116 /* Hook for a plugin to validate CHAP challenge */ 117 extern int (*chap_verify_hook)(char *name, char *ourname, int id, 118 struct chap_digest_type *digest, 119 unsigned char *challenge, unsigned char *response, 120 char *message, int message_space); 121 122 /* Called by digest code to register a digest type */ 123 extern void chap_register_digest(struct chap_digest_type *); 124 125 /* Lookup a digest handler by type */ 126 extern struct chap_digest_type *chap_find_digest(int digest_code); 127 128 /* Called by authentication code to start authenticating the peer. */ 129 extern void chap_auth_peer(int unit, char *our_name, int digest_code); 130 131 /* Called by auth. code to start authenticating us to the peer. */ 132 extern void chap_auth_with_peer(int unit, char *our_name, int digest_code); 133 134 /* Represents the CHAP protocol to the main pppd code */ 135 extern struct protent chap_protent; 136