/* * chap-new.c - New CHAP implementation. * * Copyright (c) 2003 Paul Mackerras. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. The name(s) of the authors of this software must not be used to * endorse or promote products derived from this software without * prior written permission. * * 3. Redistributions of any form whatsoever must retain the following * acknowledgment: * "This product includes software developed by Paul Mackerras * ". * * THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY * AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #include "netif/ppp/ppp_opts.h" #if PPP_SUPPORT && CHAP_SUPPORT /* don't build if not configured for use in lwipopts.h */ #ifndef CHAP_H #define CHAP_H #include "ppp.h" #ifdef __cplusplus extern "C" { #endif /* * CHAP packets begin with a standard header with code, id, len (2 bytes). */ #define CHAP_HDRLEN 4 /* * Values for the code field. */ #define CHAP_CHALLENGE 1 #define CHAP_RESPONSE 2 #define CHAP_SUCCESS 3 #define CHAP_FAILURE 4 /* * CHAP digest codes. */ #define CHAP_MD5 5 #if MSCHAP_SUPPORT #define CHAP_MICROSOFT 0x80 #define CHAP_MICROSOFT_V2 0x81 #endif /* MSCHAP_SUPPORT */ /* * Semi-arbitrary limits on challenge and response fields. */ #define MAX_CHALLENGE_LEN 64 #define MAX_RESPONSE_LEN 64 /* * These limits apply to challenge and response packets we send. * The +4 is the +1 that we actually need rounded up. */ #define CHAL_MAX_PKTLEN (PPP_HDRLEN + CHAP_HDRLEN + 4 + MAX_CHALLENGE_LEN + MAXNAMELEN) #define RESP_MAX_PKTLEN (PPP_HDRLEN + CHAP_HDRLEN + 4 + MAX_RESPONSE_LEN + MAXNAMELEN) /* bitmask of supported algorithms */ #if MSCHAP_SUPPORT #define MDTYPE_MICROSOFT_V2 0x1 #define MDTYPE_MICROSOFT 0x2 #endif /* MSCHAP_SUPPORT */ #define MDTYPE_MD5 0x4 #define MDTYPE_NONE 0 #if MSCHAP_SUPPORT /* Return the digest alg. ID for the most preferred digest type. */ #define CHAP_DIGEST(mdtype) \ ((mdtype) & MDTYPE_MD5)? CHAP_MD5: \ ((mdtype) & MDTYPE_MICROSOFT_V2)? CHAP_MICROSOFT_V2: \ ((mdtype) & MDTYPE_MICROSOFT)? CHAP_MICROSOFT: \ 0 #else /* !MSCHAP_SUPPORT */ #define CHAP_DIGEST(mdtype) \ ((mdtype) & MDTYPE_MD5)? CHAP_MD5: \ 0 #endif /* MSCHAP_SUPPORT */ /* Return the bit flag (lsb set) for our most preferred digest type. */ #define CHAP_MDTYPE(mdtype) ((mdtype) ^ ((mdtype) - 1)) & (mdtype) /* Return the bit flag for a given digest algorithm ID. */ #if MSCHAP_SUPPORT #define CHAP_MDTYPE_D(digest) \ ((digest) == CHAP_MICROSOFT_V2)? MDTYPE_MICROSOFT_V2: \ ((digest) == CHAP_MICROSOFT)? MDTYPE_MICROSOFT: \ ((digest) == CHAP_MD5)? MDTYPE_MD5: \ 0 #else /* !MSCHAP_SUPPORT */ #define CHAP_MDTYPE_D(digest) \ ((digest) == CHAP_MD5)? MDTYPE_MD5: \ 0 #endif /* MSCHAP_SUPPORT */ /* Can we do the requested digest? */ #if MSCHAP_SUPPORT #define CHAP_CANDIGEST(mdtype, digest) \ ((digest) == CHAP_MICROSOFT_V2)? (mdtype) & MDTYPE_MICROSOFT_V2: \ ((digest) == CHAP_MICROSOFT)? (mdtype) & MDTYPE_MICROSOFT: \ ((digest) == CHAP_MD5)? (mdtype) & MDTYPE_MD5: \ 0 #else /* !MSCHAP_SUPPORT */ #define CHAP_CANDIGEST(mdtype, digest) \ ((digest) == CHAP_MD5)? (mdtype) & MDTYPE_MD5: \ 0 #endif /* MSCHAP_SUPPORT */ /* * The code for each digest type has to supply one of these. */ struct chap_digest_type { int code; #if PPP_SERVER /* * Note: challenge and response arguments below are formatted as * a length byte followed by the actual challenge/response data. */ void (*generate_challenge)(ppp_pcb *pcb, unsigned char *challenge); int (*verify_response)(ppp_pcb *pcb, int id, const char *name, const unsigned char *secret, int secret_len, const unsigned char *challenge, const unsigned char *response, char *message, int message_space); #endif /* PPP_SERVER */ void (*make_response)(ppp_pcb *pcb, unsigned char *response, int id, const char *our_name, const unsigned char *challenge, const char *secret, int secret_len, unsigned char *priv); int (*check_success)(ppp_pcb *pcb, unsigned char *pkt, int len, unsigned char *priv); void (*handle_failure)(ppp_pcb *pcb, unsigned char *pkt, int len); }; /* * Each interface is described by chap structure. */ #if CHAP_SUPPORT typedef struct chap_client_state { u8_t flags; const char *name; const struct chap_digest_type *digest; unsigned char priv[64]; /* private area for digest's use */ } chap_client_state; #if PPP_SERVER typedef struct chap_server_state { u8_t flags; u8_t id; const char *name; const struct chap_digest_type *digest; int challenge_xmits; int challenge_pktlen; unsigned char challenge[CHAL_MAX_PKTLEN]; } chap_server_state; #endif /* PPP_SERVER */ #endif /* CHAP_SUPPORT */ #if 0 /* UNUSED */ /* Hook for a plugin to validate CHAP challenge */ extern int (*chap_verify_hook)(char *name, char *ourname, int id, const struct chap_digest_type *digest, unsigned char *challenge, unsigned char *response, char *message, int message_space); #endif /* UNUSED */ #if PPP_SERVER /* Called by authentication code to start authenticating the peer. */ extern void chap_auth_peer(ppp_pcb *pcb, const char *our_name, int digest_code); #endif /* PPP_SERVER */ /* Called by auth. code to start authenticating us to the peer. */ extern void chap_auth_with_peer(ppp_pcb *pcb, const char *our_name, int digest_code); /* Represents the CHAP protocol to the main pppd code */ extern const struct protent chap_protent; #ifdef __cplusplus } #endif #endif /* CHAP_H */ #endif /* PPP_SUPPORT && CHAP_SUPPORT */