X-Git-Url: https://git.ozlabs.org/?a=blobdiff_plain;f=pppd%2Feap.c;h=6cb595f5b7c57b78cdd22ed790928535f4f29777;hb=4a54e34cf5629f9fed61f0b7d69ee3ba4d874bc6;hp=ede5ff0d3a2f09fd7015763bfadfdbda7abc0902;hpb=431469a02ce74e5fe4b9943e86b9bfc272882fcb;p=ppp.git diff --git a/pppd/eap.c b/pppd/eap.c index ede5ff0..6cb595f 100644 --- a/pppd/eap.c +++ b/pppd/eap.c @@ -48,9 +48,9 @@ * Implemented EAP-TLS authentication */ -/* - * TODO: - */ +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif #include #include @@ -67,8 +67,14 @@ #include "pathnames.h" #include "md5.h" #include "eap.h" +#ifdef USE_PEAP +#include "peap.h" +#endif /* USE_PEAP */ #ifdef USE_SRP +#ifdef HAVE_TIME_H +#include +#endif #include #include #include @@ -82,10 +88,12 @@ #ifdef USE_EAPTLS #include "eap-tls.h" #endif /* USE_EAPTLS */ + #ifdef CHAPMS -#include "magic.h" #include "chap_ms.h" #include "chap-new.h" + +extern int chapms_strip_domain; #endif /* CHAPMS */ eap_state eap_states[NUM_PPP]; /* EAP state; one for each unit */ @@ -222,6 +230,10 @@ eap_init(int unit) #ifdef USE_EAPTLS esp->es_client.ea_using_eaptls = 0; #endif /* USE_EAPTLS */ +#ifdef CHAPMS + esp->es_client.digest = chap_find_digest(CHAP_MICROSOFT_V2); + esp->es_server.digest = chap_find_digest(CHAP_MICROSOFT_V2); +#endif } /* @@ -550,7 +562,7 @@ eap_figure_next_state(eap_state *esp, int status) tpw.pebuf.name = esp->es_server.ea_peer; tpw.pebuf.password.len = t_fromb64((char *)tpw.pwbuf, cp); - tpw.pebuf.password.data = tpw.pwbuf; + tpw.pebuf.password.data = (char*) tpw.pwbuf; tpw.pebuf.salt.len = t_fromb64((char *)tpw.saltbuf, cp2); tpw.pebuf.salt.data = tpw.saltbuf; @@ -716,92 +728,6 @@ eap_figure_next_state(eap_state *esp, int status) } #if CHAPMS -static int -eap_chapms2_verify_response(int id, char *name, - unsigned char *secret, int secret_len, - unsigned char *challenge, unsigned char *response, - char *message, int message_space) -{ - unsigned char md[MS_CHAP2_RESPONSE_LEN]; - char saresponse[MS_AUTH_RESPONSE_LENGTH+1]; - int challenge_len, response_len; - - challenge_len = *challenge++; /* skip length, is 16 */ - response_len = *response++; - if (response_len != MS_CHAP2_RESPONSE_LEN) - goto bad; /* not even the right length */ - - /* Generate the expected response and our mutual auth. */ - ChapMS2(challenge, &response[MS_CHAP2_PEER_CHALLENGE], name, - (char *)secret, secret_len, md, - (unsigned char *)saresponse, MS_CHAP2_AUTHENTICATOR); - - /* compare MDs and send the appropriate status */ - /* - * Per RFC 2759, success message must be formatted as - * "S= M=" - * where - * is the Authenticator Response (mutual auth) - * is a text message - * - * However, some versions of Windows (win98 tested) do not know - * about the M= part (required per RFC 2759) and flag - * it as an error (reported incorrectly as an encryption error - * to the user). Since the RFC requires it, and it can be - * useful information, we supply it if the peer is a conforming - * system. Luckily (?), win98 sets the Flags field to 0x04 - * (contrary to RFC requirements) so we can use that to - * distinguish between conforming and non-conforming systems. - * - * Special thanks to Alex Swiridov for - * help debugging this. - */ - if (memcmp(&md[MS_CHAP2_NTRESP], &response[MS_CHAP2_NTRESP], - MS_CHAP2_NTRESP_LEN) == 0) { - if (response[MS_CHAP2_FLAGS]) - slprintf(message, message_space, "S=%s", saresponse); - else - slprintf(message, message_space, "S=%s M=%s", - saresponse, "Access granted"); - return 1; - } - - bad: - /* - * Failure message must be formatted as - * "E=e R=r C=c V=v M=m" - * where - * e = error code (we use 691, ERROR_AUTHENTICATION_FAILURE) - * r = retry (we use 1, ok to retry) - * c = challenge to use for next response, we reuse previous - * v = Change Password version supported, we use 0 - * m = text message - * - * The M=m part is only for MS-CHAPv2. Neither win2k nor - * win98 (others untested) display the message to the user anyway. - * They also both ignore the E=e code. - * - * Note that it's safe to reuse the same challenge as we don't - * actually accept another response based on the error message - * (and no clients try to resend a response anyway). - * - * Basically, this whole bit is useless code, even the small - * implementation here is only because of overspecification. - */ - slprintf(message, message_space, "E=691 R=1 C=%0.*B V=0 M=%s", - challenge_len, challenge, "Access denied"); - return 0; -} - -static struct chap_digest_type eap_chapms2_digest = { - CHAP_MICROSOFT_V2, /* code */ - NULL, /* chapms2_generate_challenge, */ - eap_chapms2_verify_response, - NULL, /* chapms2_make_response, */ - NULL, /* chapms2_check_success, */ - NULL, /* chapms_handle_failure, */ -}; - /* * eap_chap_verify_response - check whether the peer's response matches * what we think it should be. Returns 1 if it does (authentication @@ -958,10 +884,9 @@ eap_send_request(eap_state *esp) #ifdef CHAPMS case eapMSCHAPv2Chall: - challen = 0x10; + esp->es_server.digest->generate_challenge(esp->es_challenge); + challen = esp->es_challenge[0]; esp->es_challen = challen; - esp->es_challenge[0] = challen; - random_bytes(&esp->es_challenge[1], challen); PUTCHAR(EAPT_MSCHAPV2, outp); PUTCHAR(CHAP_CHALLENGE, outp); @@ -1673,6 +1598,39 @@ write_pseudonym(eap_state *esp, u_char *inp, int len, int id) } #endif /* USE_SRP */ +#if CHAPMS +/* + * Format and send an CHAPV2-Challenge EAP Response message. + */ +static void +eap_chapv2_response(eap_state *esp, u_char id, u_char chapid, u_char *response, char *user, int user_len) +{ + u_char *outp; + int msglen; + + outp = outpacket_buf; + + MAKEHEADER(outp, PPP_EAP); + + PUTCHAR(EAP_RESPONSE, outp); + PUTCHAR(id, outp); + esp->es_client.ea_id = id; + msglen = EAP_HEADERLEN + 6 * sizeof (u_char) + MS_CHAP2_RESPONSE_LEN + user_len; + PUTSHORT(msglen, outp); + PUTCHAR(EAPT_MSCHAPV2, outp); + PUTCHAR(CHAP_RESPONSE, outp); + PUTCHAR(chapid, outp); + PUTCHAR(0, outp); + /* len */ + PUTCHAR(5 + user_len + MS_CHAP2_RESPONSE_LEN, outp); + BCOPY(response, outp, MS_CHAP2_RESPONSE_LEN+1); // VLEN + VALUE + INCPTR(MS_CHAP2_RESPONSE_LEN+1, outp); + BCOPY(user, outp, user_len); + + output(esp->es_unit, outpacket_buf, PPP_HDRLEN + msglen); +} +#endif + /* * eap_request - Receive EAP Request message (client mode). */ @@ -1859,7 +1817,7 @@ eap_request(eap_state *esp, u_char *inp, int id, int len) /* Init ssl session */ if(!eaptls_init_ssl_client(esp)) { dbglog("cannot init ssl"); - eap_send_nak(esp, id, EAPT_TLS); + eap_send_nak(esp, id, EAPT_MSCHAPV2); esp->es_client.ea_using_eaptls = 0; break; } @@ -1871,7 +1829,7 @@ eap_request(eap_state *esp, u_char *inp, int id, int len) } /* The server has sent a bad start packet. */ - eap_send_nak(esp, id, EAPT_TLS); + eap_send_nak(esp, id, EAPT_MSCHAPV2); break; case eapTlsRecvAck: @@ -1915,7 +1873,7 @@ eap_request(eap_state *esp, u_char *inp, int id, int len) break; default: - eap_send_nak(esp, id, EAPT_TLS); + eap_send_nak(esp, id, EAPT_MSCHAPV2); esp->es_client.ea_using_eaptls = 0; break; } @@ -2154,6 +2112,136 @@ eap_request(eap_state *esp, u_char *inp, int id, int len) } break; #endif /* USE_SRP */ + +#ifdef CHAPMS + case EAPT_MSCHAPV2: + if (len < 4) { + error("EAP: received invalid MSCHAPv2 packet, too short"); + return; + } + unsigned char opcode; + GETCHAR(opcode, inp); + unsigned char chapid; /* Chapv2-ID */ + GETCHAR(chapid, inp); + short mssize; + GETSHORT(mssize, inp); + + /* Validate the mssize field */ + if (len != mssize) { + error("EAP: received invalid MSCHAPv2 packet, invalid length"); + return; + } + len -= 4; + + /* If MSCHAPv2 digest was not found, NAK the packet */ + if (!esp->es_client.digest) { + error("EAP MSCHAPv2 not supported"); + eap_send_nak(esp, id, EAPT_SRP); + return; + } + + switch (opcode) { + case CHAP_CHALLENGE: { + + /* make_response() expects: VLEN + VALUE */ + u_char *challenge = inp; + + unsigned char vsize; + GETCHAR(vsize, inp); + len -= 1; + + /* Validate the VALUE field */ + if (vsize != MS_CHAP2_PEER_CHAL_LEN || len < MS_CHAP2_PEER_CHAL_LEN) { + error("EAP: received invalid MSCHAPv2 packet, invalid value-length: %d", vsize); + return; + } + + /* Increment past the VALUE field */ + INCPTR(MS_CHAP2_PEER_CHAL_LEN, inp); + len -= MS_CHAP2_PEER_CHAL_LEN; + + /* Extract the hostname */ + rhostname[0] = '\0'; + if (len > 0) { + if (len >= sizeof (rhostname)) { + dbglog("EAP: trimming really long peer name down"); + len = sizeof(rhostname) - 1; + } + BCOPY(inp, rhostname, len); + rhostname[len] = '\0'; + } + + /* In case the remote doesn't give us his name. */ + if (explicit_remote || (remote_name[0] != '\0' && len == 0)) + strlcpy(rhostname, remote_name, sizeof(rhostname)); + + /* Get the secret for authenticating ourselves with the specified host. */ + if (!get_secret(esp->es_unit, esp->es_client.ea_name, + rhostname, secret, &secret_len, 0)) { + dbglog("EAP: no CHAP secret for auth to %q", rhostname); + eap_send_nak(esp, id, EAPT_SRP); + break; + } + esp->es_client.ea_namelen = strlen(esp->es_client.ea_name); + + /* Create the MSCHAPv2 response (and add to cache) */ + unsigned char response[MS_CHAP2_RESPONSE_LEN+1]; // VLEN + VALUE + esp->es_client.digest->make_response(response, chapid, esp->es_client.ea_name, + challenge, secret, secret_len, NULL); + + eap_chapv2_response(esp, id, chapid, response, esp->es_client.ea_name, esp->es_client.ea_namelen); + break; + } + case CHAP_SUCCESS: { + + /* Check response for mutual authentication */ + u_char status = CHAP_FAILURE; + if (esp->es_client.digest->check_success(chapid, inp, len) == 1) { + info("Chap authentication succeeded! %.*v", len, inp); + status = CHAP_SUCCESS; + } + eap_send_response(esp, id, EAPT_MSCHAPV2, &status, sizeof(status)); + break; + } + case CHAP_FAILURE: { + + /* Process the failure string, and log appropriate information */ + esp->es_client.digest->handle_failure(inp, len); + + u_char status = CHAP_FAILURE; + eap_send_response(esp, id, EAPT_MSCHAPV2, &status, sizeof(status)); + goto client_failure; /* force termination */ + } + default: + + error("EAP: received invalid MSCHAPv2 packet, invalid or unsupported opcode: %d", opcode); + eap_send_nak(esp, id, EAPT_SRP); + } + + break; +#endif /* CHAPMS */ +#ifdef USE_PEAP + case EAPT_PEAP: + + /* Initialize the PEAP context (if not already initialized) */ + if (!esp->ea_peap) { + rhostname[0] = '\0'; + if (explicit_remote || (remote_name[0] != '\0')) { + strlcpy(rhostname, remote_name, sizeof (rhostname)); + } + if (peap_init(&esp->ea_peap, rhostname)) { + eap_send_nak(esp, id, EAPT_TLS); + break; + } + } + + /* Process the PEAP packet */ + if (peap_process(esp, id, inp, len)) { + eap_send_nak(esp, id, EAPT_TLS); + } + + break; +#endif /* USE_PEAP */ default: info("EAP: unknown authentication type %d; Naking", typenum); @@ -2168,13 +2256,13 @@ eap_request(eap_state *esp, u_char *inp, int id, int len) } return; -#ifdef USE_SRP client_failure: esp->es_client.ea_state = eapBadAuth; if (esp->es_client.ea_timeout > 0) { UNTIMEOUT(eap_client_timeout, (void *)esp); } esp->es_client.ea_session = NULL; +#ifdef USE_SRP t_clientclose(tc); auth_withpeer_fail(esp->es_unit, PPP_EAP); #endif /* USE_SRP */ @@ -2198,8 +2286,6 @@ eap_response(eap_state *esp, u_char *inp, int id, int len) struct t_num A; SHA1_CTX ctxt; u_char dig[SHA_DIGESTSIZE]; - SHA1_CTX ctxt; - u_char dig[SHA_DIGESTSIZE]; #endif /* USE_SRP */ #ifdef USE_EAPTLS @@ -2357,6 +2443,12 @@ eap_response(eap_state *esp, u_char *inp, int id, int len) #ifdef CHAPMS case EAPT_MSCHAPV2: info("EAP: peer proposes MSCHAPv2"); + /* If MSCHAPv2 digest was not found, NAK the packet */ + if (!esp->es_server.digest) { + error("EAP MSCHAPv2 not supported"); + eap_send_nak(esp, id, EAPT_SRP); + break; + } esp->es_server.ea_state = eapMSCHAPv2Chall; break; #endif /* CHAPMS */ @@ -2486,6 +2578,14 @@ eap_response(eap_state *esp, u_char *inp, int id, int len) (remote_name[0] != '\0' && vallen == len)) strlcpy(rhostname, remote_name, sizeof (rhostname)); + /* strip the MS domain name */ + if (chapms_strip_domain && strrchr(rhostname, '\\')) { + char tmp[MAXNAMELEN+1]; + + strcpy(tmp, strrchr(rhostname, '\\') + 1); + strcpy(rhostname, tmp); + } + if (chap_verify_hook) chap_verifier = chap_verify_hook; else @@ -2495,7 +2595,7 @@ eap_response(eap_state *esp, u_char *inp, int id, int len) if ((*chap_verifier)(rhostname, esp->es_server.ea_name, id, - &eap_chapms2_digest, + esp->es_server.digest, esp->es_challenge, inp - 1, response_message, @@ -2695,6 +2795,10 @@ eap_success(eap_state *esp, u_char *inp, int id, int len) PRINTMSG(inp, len); } +#ifdef USE_PEAP + peap_finish(&esp->ea_peap); +#endif + esp->es_client.ea_state = eapOpen; auth_withpeer_success(esp->es_unit, PPP_EAP, 0); } @@ -2729,6 +2833,11 @@ eap_failure(eap_state *esp, u_char *inp, int id, int len) esp->es_client.ea_state = eapBadAuth; error("EAP: peer reports authentication failure"); + +#ifdef USE_PEAP + peap_finish(&esp->ea_peap); +#endif + auth_withpeer_fail(esp->es_unit, PPP_EAP); } @@ -2952,6 +3061,7 @@ eap_printpkt(u_char *inp, int inlen, break; #endif /* USE_EAPTLS */ +#ifdef USE_SRP case EAPT_SRP: if (len < 3) goto truncated; @@ -3039,6 +3149,7 @@ eap_printpkt(u_char *inp, int inlen, break; } break; +#endif /* USE_SRP */ } break; @@ -3091,7 +3202,7 @@ eap_printpkt(u_char *inp, int inlen, len--; printer(arg, " = 1 && - rtype < sizeof (eap_typenames) / sizeof (char *)) + rtype <= sizeof (eap_typenames) / sizeof (char *)) printer(arg, " (%s)", eap_typenames[rtype-1]); printer(arg, ">"); break; @@ -3164,6 +3275,7 @@ eap_printpkt(u_char *inp, int inlen, break; #endif /* CHAPMS */ +#ifdef USE_SRP case EAPT_SRP: if (len < 1) goto truncated; @@ -3208,6 +3320,7 @@ eap_printpkt(u_char *inp, int inlen, break; } break; +#endif /* USE_SRP */ } break;