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diff --git a/lwip/src/netif/ppp/eap.c b/lwip/src/netif/ppp/eap.c
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+/*
+ * eap.c - Extensible Authentication Protocol for PPP (RFC 2284)
+ *
+ * Copyright (c) 2001 by Sun Microsystems, Inc.
+ * All rights reserved.
+ *
+ * Non-exclusive rights to redistribute, modify, translate, and use
+ * this software in source and binary forms, in whole or in part, is
+ * hereby granted, provided that the above copyright notice is
+ * duplicated in any source form, and that neither the name of the
+ * copyright holder nor the author is used to endorse or promote
+ * products derived from this software.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * Original version by James Carlson
+ *
+ * This implementation of EAP supports MD5-Challenge and SRP-SHA1
+ * authentication styles. Note that support of MD5-Challenge is a
+ * requirement of RFC 2284, and that it's essentially just a
+ * reimplementation of regular RFC 1994 CHAP using EAP messages.
+ *
+ * As an authenticator ("server"), there are multiple phases for each
+ * style. In the first phase of each style, the unauthenticated peer
+ * name is queried using the EAP Identity request type. If the
+ * "remotename" option is used, then this phase is skipped, because
+ * the peer's name is presumed to be known.
+ *
+ * For MD5-Challenge, there are two phases, and the second phase
+ * consists of sending the challenge itself and handling the
+ * associated response.
+ *
+ * For SRP-SHA1, there are four phases. The second sends 's', 'N',
+ * and 'g'. The reply contains 'A'. The third sends 'B', and the
+ * reply contains 'M1'. The forth sends the 'M2' value.
+ *
+ * As an authenticatee ("client"), there's just a single phase --
+ * responding to the queries generated by the peer. EAP is an
+ * authenticator-driven protocol.
+ *
+ * Based on draft-ietf-pppext-eap-srp-03.txt.
+ */
+
+#include "netif/ppp/ppp_opts.h"
+#if PPP_SUPPORT && EAP_SUPPORT /* don't build if not configured for use in lwipopts.h */
+
+#include "netif/ppp/ppp_impl.h"
+#include "netif/ppp/eap.h"
+#include "netif/ppp/magic.h"
+#include "netif/ppp/pppcrypt.h"
+
+#ifdef USE_SRP
+#include <t_pwd.h>
+#include <t_server.h>
+#include <t_client.h>
+#endif /* USE_SRP */
+
+#ifndef SHA_DIGESTSIZE
+#define SHA_DIGESTSIZE 20
+#endif
+
+#ifdef USE_SRP
+static char *pn_secret = NULL; /* Pseudonym generating secret */
+#endif
+
+#if PPP_OPTIONS
+/*
+ * Command-line options.
+ */
+static option_t eap_option_list[] = {
+ { "eap-restart", o_int, &eap_states[0].es_server.ea_timeout,
+ "Set retransmit timeout for EAP Requests (server)" },
+ { "eap-max-sreq", o_int, &eap_states[0].es_server.ea_maxrequests,
+ "Set max number of EAP Requests sent (server)" },
+ { "eap-timeout", o_int, &eap_states[0].es_client.ea_timeout,
+ "Set time limit for peer EAP authentication" },
+ { "eap-max-rreq", o_int, &eap_states[0].es_client.ea_maxrequests,
+ "Set max number of EAP Requests allows (client)" },
+ { "eap-interval", o_int, &eap_states[0].es_rechallenge,
+ "Set interval for EAP rechallenge" },
+#ifdef USE_SRP
+ { "srp-interval", o_int, &eap_states[0].es_lwrechallenge,
+ "Set interval for SRP lightweight rechallenge" },
+ { "srp-pn-secret", o_string, &pn_secret,
+ "Long term pseudonym generation secret" },
+ { "srp-use-pseudonym", o_bool, &eap_states[0].es_usepseudo,
+ "Use pseudonym if offered one by server", 1 },
+#endif
+ { NULL }
+};
+#endif /* PPP_OPTIONS */
+
+/*
+ * Protocol entry points.
+ */
+static void eap_init(ppp_pcb *pcb);
+static void eap_input(ppp_pcb *pcb, u_char *inp, int inlen);
+static void eap_protrej(ppp_pcb *pcb);
+static void eap_lowerup(ppp_pcb *pcb);
+static void eap_lowerdown(ppp_pcb *pcb);
+#if PRINTPKT_SUPPORT
+static int eap_printpkt(const u_char *inp, int inlen,
+ void (*)(void *arg, const char *fmt, ...), void *arg);
+#endif /* PRINTPKT_SUPPORT */
+
+const struct protent eap_protent = {
+ PPP_EAP, /* protocol number */
+ eap_init, /* initialization procedure */
+ eap_input, /* process a received packet */
+ eap_protrej, /* process a received protocol-reject */
+ eap_lowerup, /* lower layer has gone up */
+ eap_lowerdown, /* lower layer has gone down */
+ NULL, /* open the protocol */
+ NULL, /* close the protocol */
+#if PRINTPKT_SUPPORT
+ eap_printpkt, /* print a packet in readable form */
+#endif /* PRINTPKT_SUPPORT */
+#if PPP_DATAINPUT
+ NULL, /* process a received data packet */
+#endif /* PPP_DATAINPUT */
+#if PRINTPKT_SUPPORT
+ "EAP", /* text name of protocol */
+ NULL, /* text name of corresponding data protocol */
+#endif /* PRINTPKT_SUPPORT */
+#if PPP_OPTIONS
+ eap_option_list, /* list of command-line options */
+ NULL, /* check requested options; assign defaults */
+#endif /* PPP_OPTIONS */
+#if DEMAND_SUPPORT
+ NULL, /* configure interface for demand-dial */
+ NULL /* say whether to bring up link for this pkt */
+#endif /* DEMAND_SUPPORT */
+};
+
+#ifdef USE_SRP
+/*
+ * A well-known 2048 bit modulus.
+ */
+static const u_char wkmodulus[] = {
+ 0xAC, 0x6B, 0xDB, 0x41, 0x32, 0x4A, 0x9A, 0x9B,
+ 0xF1, 0x66, 0xDE, 0x5E, 0x13, 0x89, 0x58, 0x2F,
+ 0xAF, 0x72, 0xB6, 0x65, 0x19, 0x87, 0xEE, 0x07,
+ 0xFC, 0x31, 0x92, 0x94, 0x3D, 0xB5, 0x60, 0x50,
+ 0xA3, 0x73, 0x29, 0xCB, 0xB4, 0xA0, 0x99, 0xED,
+ 0x81, 0x93, 0xE0, 0x75, 0x77, 0x67, 0xA1, 0x3D,
+ 0xD5, 0x23, 0x12, 0xAB, 0x4B, 0x03, 0x31, 0x0D,
+ 0xCD, 0x7F, 0x48, 0xA9, 0xDA, 0x04, 0xFD, 0x50,
+ 0xE8, 0x08, 0x39, 0x69, 0xED, 0xB7, 0x67, 0xB0,
+ 0xCF, 0x60, 0x95, 0x17, 0x9A, 0x16, 0x3A, 0xB3,
+ 0x66, 0x1A, 0x05, 0xFB, 0xD5, 0xFA, 0xAA, 0xE8,
+ 0x29, 0x18, 0xA9, 0x96, 0x2F, 0x0B, 0x93, 0xB8,
+ 0x55, 0xF9, 0x79, 0x93, 0xEC, 0x97, 0x5E, 0xEA,
+ 0xA8, 0x0D, 0x74, 0x0A, 0xDB, 0xF4, 0xFF, 0x74,
+ 0x73, 0x59, 0xD0, 0x41, 0xD5, 0xC3, 0x3E, 0xA7,
+ 0x1D, 0x28, 0x1E, 0x44, 0x6B, 0x14, 0x77, 0x3B,
+ 0xCA, 0x97, 0xB4, 0x3A, 0x23, 0xFB, 0x80, 0x16,
+ 0x76, 0xBD, 0x20, 0x7A, 0x43, 0x6C, 0x64, 0x81,
+ 0xF1, 0xD2, 0xB9, 0x07, 0x87, 0x17, 0x46, 0x1A,
+ 0x5B, 0x9D, 0x32, 0xE6, 0x88, 0xF8, 0x77, 0x48,
+ 0x54, 0x45, 0x23, 0xB5, 0x24, 0xB0, 0xD5, 0x7D,
+ 0x5E, 0xA7, 0x7A, 0x27, 0x75, 0xD2, 0xEC, 0xFA,
+ 0x03, 0x2C, 0xFB, 0xDB, 0xF5, 0x2F, 0xB3, 0x78,
+ 0x61, 0x60, 0x27, 0x90, 0x04, 0xE5, 0x7A, 0xE6,
+ 0xAF, 0x87, 0x4E, 0x73, 0x03, 0xCE, 0x53, 0x29,
+ 0x9C, 0xCC, 0x04, 0x1C, 0x7B, 0xC3, 0x08, 0xD8,
+ 0x2A, 0x56, 0x98, 0xF3, 0xA8, 0xD0, 0xC3, 0x82,
+ 0x71, 0xAE, 0x35, 0xF8, 0xE9, 0xDB, 0xFB, 0xB6,
+ 0x94, 0xB5, 0xC8, 0x03, 0xD8, 0x9F, 0x7A, 0xE4,
+ 0x35, 0xDE, 0x23, 0x6D, 0x52, 0x5F, 0x54, 0x75,
+ 0x9B, 0x65, 0xE3, 0x72, 0xFC, 0xD6, 0x8E, 0xF2,
+ 0x0F, 0xA7, 0x11, 0x1F, 0x9E, 0x4A, 0xFF, 0x73
+};
+#endif
+
+#if PPP_SERVER
+/* Local forward declarations. */
+static void eap_server_timeout(void *arg);
+#endif /* PPP_SERVER */
+
+/*
+ * Convert EAP state code to printable string for debug.
+ */
+static const char * eap_state_name(enum eap_state_code esc)
+{
+ static const char *state_names[] = { EAP_STATES };
+
+ return (state_names[(int)esc]);
+}
+
+/*
+ * eap_init - Initialize state for an EAP user. This is currently
+ * called once by main() during start-up.
+ */
+static void eap_init(ppp_pcb *pcb) {
+
+ BZERO(&pcb->eap, sizeof(eap_state));
+#if PPP_SERVER
+ pcb->eap.es_server.ea_id = magic();
+#endif /* PPP_SERVER */
+}
+
+/*
+ * eap_client_timeout - Give up waiting for the peer to send any
+ * Request messages.
+ */
+static void eap_client_timeout(void *arg) {
+ ppp_pcb *pcb = (ppp_pcb*)arg;
+
+ if (!eap_client_active(pcb))
+ return;
+
+ ppp_error("EAP: timeout waiting for Request from peer");
+ auth_withpeer_fail(pcb, PPP_EAP);
+ pcb->eap.es_client.ea_state = eapBadAuth;
+}
+
+/*
+ * eap_authwithpeer - Authenticate to our peer (behave as client).
+ *
+ * Start client state and wait for requests. This is called only
+ * after eap_lowerup.
+ */
+void eap_authwithpeer(ppp_pcb *pcb, const char *localname) {
+
+ if(NULL == localname)
+ return;
+
+ /* Save the peer name we're given */
+ pcb->eap.es_client.ea_name = localname;
+ pcb->eap.es_client.ea_namelen = strlen(localname);
+
+ pcb->eap.es_client.ea_state = eapListen;
+
+ /*
+ * Start a timer so that if the other end just goes
+ * silent, we don't sit here waiting forever.
+ */
+ if (pcb->settings.eap_req_time > 0)
+ TIMEOUT(eap_client_timeout, pcb,
+ pcb->settings.eap_req_time);
+}
+
+#if PPP_SERVER
+/*
+ * Format a standard EAP Failure message and send it to the peer.
+ * (Server operation)
+ */
+static void eap_send_failure(ppp_pcb *pcb) {
+ struct pbuf *p;
+ u_char *outp;
+
+ p = pbuf_alloc(PBUF_RAW, (u16_t)(PPP_HDRLEN + EAP_HEADERLEN), PPP_CTRL_PBUF_TYPE);
+ if(NULL == p)
+ return;
+ if(p->tot_len != p->len) {
+ pbuf_free(p);
+ return;
+ }
+
+ outp = (u_char*)p->payload;
+
+ MAKEHEADER(outp, PPP_EAP);
+
+ PUTCHAR(EAP_FAILURE, outp);
+ pcb->eap.es_server.ea_id++;
+ PUTCHAR(pcb->eap.es_server.ea_id, outp);
+ PUTSHORT(EAP_HEADERLEN, outp);
+
+ ppp_write(pcb, p);
+
+ pcb->eap.es_server.ea_state = eapBadAuth;
+ auth_peer_fail(pcb, PPP_EAP);
+}
+
+/*
+ * Format a standard EAP Success message and send it to the peer.
+ * (Server operation)
+ */
+static void eap_send_success(ppp_pcb *pcb) {
+ struct pbuf *p;
+ u_char *outp;
+
+ p = pbuf_alloc(PBUF_RAW, (u16_t)(PPP_HDRLEN + EAP_HEADERLEN), PPP_CTRL_PBUF_TYPE);
+ if(NULL == p)
+ return;
+ if(p->tot_len != p->len) {
+ pbuf_free(p);
+ return;
+ }
+
+ outp = (u_char*)p->payload;
+
+ MAKEHEADER(outp, PPP_EAP);
+
+ PUTCHAR(EAP_SUCCESS, outp);
+ pcb->eap.es_server.ea_id++;
+ PUTCHAR(pcb->eap.es_server.ea_id, outp);
+ PUTSHORT(EAP_HEADERLEN, outp);
+
+ ppp_write(pcb, p);
+
+ auth_peer_success(pcb, PPP_EAP, 0,
+ pcb->eap.es_server.ea_peer, pcb->eap.es_server.ea_peerlen);
+}
+#endif /* PPP_SERVER */
+
+#ifdef USE_SRP
+/*
+ * Set DES key according to pseudonym-generating secret and current
+ * date.
+ */
+static bool
+pncrypt_setkey(int timeoffs)
+{
+ struct tm *tp;
+ char tbuf[9];
+ SHA1_CTX ctxt;
+ u_char dig[SHA_DIGESTSIZE];
+ time_t reftime;
+
+ if (pn_secret == NULL)
+ return (0);
+ reftime = time(NULL) + timeoffs;
+ tp = localtime(&reftime);
+ SHA1Init(&ctxt);
+ SHA1Update(&ctxt, pn_secret, strlen(pn_secret));
+ strftime(tbuf, sizeof (tbuf), "%Y%m%d", tp);
+ SHA1Update(&ctxt, tbuf, strlen(tbuf));
+ SHA1Final(dig, &ctxt);
+ /* FIXME: if we want to do SRP, we need to find a way to pass the PolarSSL des_context instead of using static memory */
+ return (DesSetkey(dig));
+}
+
+static char base64[] =
+"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+
+struct b64state {
+ u32_t bs_bits;
+ int bs_offs;
+};
+
+static int
+b64enc(bs, inp, inlen, outp)
+struct b64state *bs;
+u_char *inp;
+int inlen;
+u_char *outp;
+{
+ int outlen = 0;
+
+ while (inlen > 0) {
+ bs->bs_bits = (bs->bs_bits << 8) | *inp++;
+ inlen--;
+ bs->bs_offs += 8;
+ if (bs->bs_offs >= 24) {
+ *outp++ = base64[(bs->bs_bits >> 18) & 0x3F];
+ *outp++ = base64[(bs->bs_bits >> 12) & 0x3F];
+ *outp++ = base64[(bs->bs_bits >> 6) & 0x3F];
+ *outp++ = base64[bs->bs_bits & 0x3F];
+ outlen += 4;
+ bs->bs_offs = 0;
+ bs->bs_bits = 0;
+ }
+ }
+ return (outlen);
+}
+
+static int
+b64flush(bs, outp)
+struct b64state *bs;
+u_char *outp;
+{
+ int outlen = 0;
+
+ if (bs->bs_offs == 8) {
+ *outp++ = base64[(bs->bs_bits >> 2) & 0x3F];
+ *outp++ = base64[(bs->bs_bits << 4) & 0x3F];
+ outlen = 2;
+ } else if (bs->bs_offs == 16) {
+ *outp++ = base64[(bs->bs_bits >> 10) & 0x3F];
+ *outp++ = base64[(bs->bs_bits >> 4) & 0x3F];
+ *outp++ = base64[(bs->bs_bits << 2) & 0x3F];
+ outlen = 3;
+ }
+ bs->bs_offs = 0;
+ bs->bs_bits = 0;
+ return (outlen);
+}
+
+static int
+b64dec(bs, inp, inlen, outp)
+struct b64state *bs;
+u_char *inp;
+int inlen;
+u_char *outp;
+{
+ int outlen = 0;
+ char *cp;
+
+ while (inlen > 0) {
+ if ((cp = strchr(base64, *inp++)) == NULL)
+ break;
+ bs->bs_bits = (bs->bs_bits << 6) | (cp - base64);
+ inlen--;
+ bs->bs_offs += 6;
+ if (bs->bs_offs >= 8) {
+ *outp++ = bs->bs_bits >> (bs->bs_offs - 8);
+ outlen++;
+ bs->bs_offs -= 8;
+ }
+ }
+ return (outlen);
+}
+#endif /* USE_SRP */
+
+#if PPP_SERVER
+/*
+ * Assume that current waiting server state is complete and figure
+ * next state to use based on available authentication data. 'status'
+ * indicates if there was an error in handling the last query. It is
+ * 0 for success and non-zero for failure.
+ */
+static void eap_figure_next_state(ppp_pcb *pcb, int status) {
+#ifdef USE_SRP
+ unsigned char secbuf[MAXSECRETLEN], clear[8], *sp, *dp;
+ struct t_pw tpw;
+ struct t_confent *tce, mytce;
+ char *cp, *cp2;
+ struct t_server *ts;
+ int id, i, plen, toffs;
+ u_char vals[2];
+ struct b64state bs;
+#endif /* USE_SRP */
+
+ pcb->settings.eap_timeout_time = pcb->eap.es_savedtime;
+ switch (pcb->eap.es_server.ea_state) {
+ case eapBadAuth:
+ return;
+
+ case eapIdentify:
+#ifdef USE_SRP
+ /* Discard any previous session. */
+ ts = (struct t_server *)pcb->eap.es_server.ea_session;
+ if (ts != NULL) {
+ t_serverclose(ts);
+ pcb->eap.es_server.ea_session = NULL;
+ pcb->eap.es_server.ea_skey = NULL;
+ }
+#endif /* USE_SRP */
+ if (status != 0) {
+ pcb->eap.es_server.ea_state = eapBadAuth;
+ break;
+ }
+#ifdef USE_SRP
+ /* If we've got a pseudonym, try to decode to real name. */
+ if (pcb->eap.es_server.ea_peerlen > SRP_PSEUDO_LEN &&
+ strncmp(pcb->eap.es_server.ea_peer, SRP_PSEUDO_ID,
+ SRP_PSEUDO_LEN) == 0 &&
+ (pcb->eap.es_server.ea_peerlen - SRP_PSEUDO_LEN) * 3 / 4 <
+ sizeof (secbuf)) {
+ BZERO(&bs, sizeof (bs));
+ plen = b64dec(&bs,
+ pcb->eap.es_server.ea_peer + SRP_PSEUDO_LEN,
+ pcb->eap.es_server.ea_peerlen - SRP_PSEUDO_LEN,
+ secbuf);
+ toffs = 0;
+ for (i = 0; i < 5; i++) {
+ pncrypt_setkey(toffs);
+ toffs -= 86400;
+ /* FIXME: if we want to do SRP, we need to find a way to pass the PolarSSL des_context instead of using static memory */
+ if (!DesDecrypt(secbuf, clear)) {
+ ppp_dbglog("no DES here; cannot decode "
+ "pseudonym");
+ return;
+ }
+ id = *(unsigned char *)clear;
+ if (id + 1 <= plen && id + 9 > plen)
+ break;
+ }
+ if (plen % 8 == 0 && i < 5) {
+ /*
+ * Note that this is always shorter than the
+ * original stored string, so there's no need
+ * to realloc.
+ */
+ if ((i = plen = *(unsigned char *)clear) > 7)
+ i = 7;
+ pcb->eap.es_server.ea_peerlen = plen;
+ dp = (unsigned char *)pcb->eap.es_server.ea_peer;
+ MEMCPY(dp, clear + 1, i);
+ plen -= i;
+ dp += i;
+ sp = secbuf + 8;
+ while (plen > 0) {
+ /* FIXME: if we want to do SRP, we need to find a way to pass the PolarSSL des_context instead of using static memory */
+ (void) DesDecrypt(sp, dp);
+ sp += 8;
+ dp += 8;
+ plen -= 8;
+ }
+ pcb->eap.es_server.ea_peer[
+ pcb->eap.es_server.ea_peerlen] = '\0';
+ ppp_dbglog("decoded pseudonym to \"%.*q\"",
+ pcb->eap.es_server.ea_peerlen,
+ pcb->eap.es_server.ea_peer);
+ } else {
+ ppp_dbglog("failed to decode real name");
+ /* Stay in eapIdentfy state; requery */
+ break;
+ }
+ }
+ /* Look up user in secrets database. */
+ if (get_srp_secret(pcb->eap.es_unit, pcb->eap.es_server.ea_peer,
+ pcb->eap.es_server.ea_name, (char *)secbuf, 1) != 0) {
+ /* Set up default in case SRP entry is bad */
+ pcb->eap.es_server.ea_state = eapMD5Chall;
+ /* Get t_confent based on index in srp-secrets */
+ id = strtol((char *)secbuf, &cp, 10);
+ if (*cp++ != ':' || id < 0)
+ break;
+ if (id == 0) {
+ mytce.index = 0;
+ mytce.modulus.data = (u_char *)wkmodulus;
+ mytce.modulus.len = sizeof (wkmodulus);
+ mytce.generator.data = (u_char *)"\002";
+ mytce.generator.len = 1;
+ tce = &mytce;
+ } else if ((tce = gettcid(id)) != NULL) {
+ /*
+ * Client will have to verify this modulus/
+ * generator combination, and that will take
+ * a while. Lengthen the timeout here.
+ */
+ if (pcb->settings.eap_timeout_time > 0 &&
+ pcb->settings.eap_timeout_time < 30)
+ pcb->settings.eap_timeout_time = 30;
+ } else {
+ break;
+ }
+ if ((cp2 = strchr(cp, ':')) == NULL)
+ break;
+ *cp2++ = '\0';
+ tpw.pebuf.name = pcb->eap.es_server.ea_peer;
+ tpw.pebuf.password.len = t_fromb64((char *)tpw.pwbuf,
+ cp);
+ tpw.pebuf.password.data = tpw.pwbuf;
+ tpw.pebuf.salt.len = t_fromb64((char *)tpw.saltbuf,
+ cp2);
+ tpw.pebuf.salt.data = tpw.saltbuf;
+ if ((ts = t_serveropenraw(&tpw.pebuf, tce)) == NULL)
+ break;
+ pcb->eap.es_server.ea_session = (void *)ts;
+ pcb->eap.es_server.ea_state = eapSRP1;
+ vals[0] = pcb->eap.es_server.ea_id + 1;
+ vals[1] = EAPT_SRP;
+ t_serveraddexdata(ts, vals, 2);
+ /* Generate B; must call before t_servergetkey() */
+ t_servergenexp(ts);
+ break;
+ }
+#endif /* USE_SRP */
+ pcb->eap.es_server.ea_state = eapMD5Chall;
+ break;
+
+ case eapSRP1:
+#ifdef USE_SRP
+ ts = (struct t_server *)pcb->eap.es_server.ea_session;
+ if (ts != NULL && status != 0) {
+ t_serverclose(ts);
+ pcb->eap.es_server.ea_session = NULL;
+ pcb->eap.es_server.ea_skey = NULL;
+ }
+#endif /* USE_SRP */
+ if (status == 1) {
+ pcb->eap.es_server.ea_state = eapMD5Chall;
+ } else if (status != 0 || pcb->eap.es_server.ea_session == NULL) {
+ pcb->eap.es_server.ea_state = eapBadAuth;
+ } else {
+ pcb->eap.es_server.ea_state = eapSRP2;
+ }
+ break;
+
+ case eapSRP2:
+#ifdef USE_SRP
+ ts = (struct t_server *)pcb->eap.es_server.ea_session;
+ if (ts != NULL && status != 0) {
+ t_serverclose(ts);
+ pcb->eap.es_server.ea_session = NULL;
+ pcb->eap.es_server.ea_skey = NULL;
+ }
+#endif /* USE_SRP */
+ if (status != 0 || pcb->eap.es_server.ea_session == NULL) {
+ pcb->eap.es_server.ea_state = eapBadAuth;
+ } else {
+ pcb->eap.es_server.ea_state = eapSRP3;
+ }
+ break;
+
+ case eapSRP3:
+ case eapSRP4:
+#ifdef USE_SRP
+ ts = (struct t_server *)pcb->eap.es_server.ea_session;
+ if (ts != NULL && status != 0) {
+ t_serverclose(ts);
+ pcb->eap.es_server.ea_session = NULL;
+ pcb->eap.es_server.ea_skey = NULL;
+ }
+#endif /* USE_SRP */
+ if (status != 0 || pcb->eap.es_server.ea_session == NULL) {
+ pcb->eap.es_server.ea_state = eapBadAuth;
+ } else {
+ pcb->eap.es_server.ea_state = eapOpen;
+ }
+ break;
+
+ case eapMD5Chall:
+ if (status != 0) {
+ pcb->eap.es_server.ea_state = eapBadAuth;
+ } else {
+ pcb->eap.es_server.ea_state = eapOpen;
+ }
+ break;
+
+ default:
+ pcb->eap.es_server.ea_state = eapBadAuth;
+ break;
+ }
+ if (pcb->eap.es_server.ea_state == eapBadAuth)
+ eap_send_failure(pcb);
+}
+
+/*
+ * Format an EAP Request message and send it to the peer. Message
+ * type depends on current state. (Server operation)
+ */
+static void eap_send_request(ppp_pcb *pcb) {
+ struct pbuf *p;
+ u_char *outp;
+ u_char *lenloc;
+ int outlen;
+ int len;
+ const char *str;
+#ifdef USE_SRP
+ struct t_server *ts;
+ u_char clear[8], cipher[8], dig[SHA_DIGESTSIZE], *optr, *cp;
+ int i, j;
+ struct b64state b64;
+ SHA1_CTX ctxt;
+#endif /* USE_SRP */
+
+ /* Handle both initial auth and restart */
+ if (pcb->eap.es_server.ea_state < eapIdentify &&
+ pcb->eap.es_server.ea_state != eapInitial) {
+ pcb->eap.es_server.ea_state = eapIdentify;
+#if PPP_REMOTENAME
+ if (pcb->settings.explicit_remote && pcb->remote_name) {
+ /*
+ * If we already know the peer's
+ * unauthenticated name, then there's no
+ * reason to ask. Go to next state instead.
+ */
+ int len = (int)strlen(pcb->remote_name);
+ if (len > MAXNAMELEN) {
+ len = MAXNAMELEN;
+ }
+ MEMCPY(pcb->eap.es_server.ea_peer, pcb->remote_name, len);
+ pcb->eap.es_server.ea_peer[len] = '\0';
+ pcb->eap.es_server.ea_peerlen = len;
+ eap_figure_next_state(pcb, 0);
+ }
+#endif /* PPP_REMOTENAME */
+ }
+
+ if (pcb->settings.eap_max_transmits > 0 &&
+ pcb->eap.es_server.ea_requests >= pcb->settings.eap_max_transmits) {
+ if (pcb->eap.es_server.ea_responses > 0)
+ ppp_error("EAP: too many Requests sent");
+ else
+ ppp_error("EAP: no response to Requests");
+ eap_send_failure(pcb);
+ return;
+ }
+
+ p = pbuf_alloc(PBUF_RAW, (u16_t)(PPP_CTRL_PBUF_MAX_SIZE), PPP_CTRL_PBUF_TYPE);
+ if(NULL == p)
+ return;
+ if(p->tot_len != p->len) {
+ pbuf_free(p);
+ return;
+ }
+
+ outp = (u_char*)p->payload;
+
+ MAKEHEADER(outp, PPP_EAP);
+
+ PUTCHAR(EAP_REQUEST, outp);
+ PUTCHAR(pcb->eap.es_server.ea_id, outp);
+ lenloc = outp;
+ INCPTR(2, outp);
+
+ switch (pcb->eap.es_server.ea_state) {
+ case eapIdentify:
+ PUTCHAR(EAPT_IDENTITY, outp);
+ str = "Name";
+ len = strlen(str);
+ MEMCPY(outp, str, len);
+ INCPTR(len, outp);
+ break;
+
+ case eapMD5Chall:
+ PUTCHAR(EAPT_MD5CHAP, outp);
+ /*
+ * pick a random challenge length between
+ * EAP_MIN_CHALLENGE_LENGTH and EAP_MAX_CHALLENGE_LENGTH
+ */
+ pcb->eap.es_challen = EAP_MIN_CHALLENGE_LENGTH +
+ magic_pow(EAP_MIN_MAX_POWER_OF_TWO_CHALLENGE_LENGTH);
+ PUTCHAR(pcb->eap.es_challen, outp);
+ magic_random_bytes(pcb->eap.es_challenge, pcb->eap.es_challen);
+ MEMCPY(outp, pcb->eap.es_challenge, pcb->eap.es_challen);
+ INCPTR(pcb->eap.es_challen, outp);
+ MEMCPY(outp, pcb->eap.es_server.ea_name, pcb->eap.es_server.ea_namelen);
+ INCPTR(pcb->eap.es_server.ea_namelen, outp);
+ break;
+
+#ifdef USE_SRP
+ case eapSRP1:
+ PUTCHAR(EAPT_SRP, outp);
+ PUTCHAR(EAPSRP_CHALLENGE, outp);
+
+ PUTCHAR(pcb->eap.es_server.ea_namelen, outp);
+ MEMCPY(outp, pcb->eap.es_server.ea_name, pcb->eap.es_server.ea_namelen);
+ INCPTR(pcb->eap.es_server.ea_namelen, outp);
+
+ ts = (struct t_server *)pcb->eap.es_server.ea_session;
+ assert(ts != NULL);
+ PUTCHAR(ts->s.len, outp);
+ MEMCPY(outp, ts->s.data, ts->s.len);
+ INCPTR(ts->s.len, outp);
+
+ if (ts->g.len == 1 && ts->g.data[0] == 2) {
+ PUTCHAR(0, outp);
+ } else {
+ PUTCHAR(ts->g.len, outp);
+ MEMCPY(outp, ts->g.data, ts->g.len);
+ INCPTR(ts->g.len, outp);
+ }
+
+ if (ts->n.len != sizeof (wkmodulus) ||
+ BCMP(ts->n.data, wkmodulus, sizeof (wkmodulus)) != 0) {
+ MEMCPY(outp, ts->n.data, ts->n.len);
+ INCPTR(ts->n.len, outp);
+ }
+ break;
+
+ case eapSRP2:
+ PUTCHAR(EAPT_SRP, outp);
+ PUTCHAR(EAPSRP_SKEY, outp);
+
+ ts = (struct t_server *)pcb->eap.es_server.ea_session;
+ assert(ts != NULL);
+ MEMCPY(outp, ts->B.data, ts->B.len);
+ INCPTR(ts->B.len, outp);
+ break;
+
+ case eapSRP3:
+ PUTCHAR(EAPT_SRP, outp);
+ PUTCHAR(EAPSRP_SVALIDATOR, outp);
+ PUTLONG(SRPVAL_EBIT, outp);
+ ts = (struct t_server *)pcb->eap.es_server.ea_session;
+ assert(ts != NULL);
+ MEMCPY(outp, t_serverresponse(ts), SHA_DIGESTSIZE);
+ INCPTR(SHA_DIGESTSIZE, outp);
+
+ if (pncrypt_setkey(0)) {
+ /* Generate pseudonym */
+ optr = outp;
+ cp = (unsigned char *)pcb->eap.es_server.ea_peer;
+ if ((j = i = pcb->eap.es_server.ea_peerlen) > 7)
+ j = 7;
+ clear[0] = i;
+ MEMCPY(clear + 1, cp, j);
+ i -= j;
+ cp += j;
+ /* FIXME: if we want to do SRP, we need to find a way to pass the PolarSSL des_context instead of using static memory */
+ if (!DesEncrypt(clear, cipher)) {
+ ppp_dbglog("no DES here; not generating pseudonym");
+ break;
+ }
+ BZERO(&b64, sizeof (b64));
+ outp++; /* space for pseudonym length */
+ outp += b64enc(&b64, cipher, 8, outp);
+ while (i >= 8) {
+ /* FIXME: if we want to do SRP, we need to find a way to pass the PolarSSL des_context instead of using static memory */
+ (void) DesEncrypt(cp, cipher);
+ outp += b64enc(&b64, cipher, 8, outp);
+ cp += 8;
+ i -= 8;
+ }
+ if (i > 0) {
+ MEMCPY(clear, cp, i);
+ cp += i;
+ magic_random_bytes(cp, 8-i);
+ /* FIXME: if we want to do SRP, we need to find a way to pass the PolarSSL des_context instead of using static memory */
+ (void) DesEncrypt(clear, cipher);
+ outp += b64enc(&b64, cipher, 8, outp);
+ }
+ outp += b64flush(&b64, outp);
+
+ /* Set length and pad out to next 20 octet boundary */
+ i = outp - optr - 1;
+ *optr = i;
+ i %= SHA_DIGESTSIZE;
+ if (i != 0) {
+ magic_random_bytes(outp, SHA_DIGESTSIZE-i);
+ INCPTR(SHA_DIGESTSIZE-i, outp);
+ }
+
+ /* Obscure the pseudonym with SHA1 hash */
+ SHA1Init(&ctxt);
+ SHA1Update(&ctxt, &pcb->eap.es_server.ea_id, 1);
+ SHA1Update(&ctxt, pcb->eap.es_server.ea_skey,
+ SESSION_KEY_LEN);
+ SHA1Update(&ctxt, pcb->eap.es_server.ea_peer,
+ pcb->eap.es_server.ea_peerlen);
+ while (optr < outp) {
+ SHA1Final(dig, &ctxt);
+ cp = dig;
+ while (cp < dig + SHA_DIGESTSIZE)
+ *optr++ ^= *cp++;
+ SHA1Init(&ctxt);
+ SHA1Update(&ctxt, &pcb->eap.es_server.ea_id, 1);
+ SHA1Update(&ctxt, pcb->eap.es_server.ea_skey,
+ SESSION_KEY_LEN);
+ SHA1Update(&ctxt, optr - SHA_DIGESTSIZE,
+ SHA_DIGESTSIZE);
+ }
+ }
+ break;
+
+ case eapSRP4:
+ PUTCHAR(EAPT_SRP, outp);
+ PUTCHAR(EAPSRP_LWRECHALLENGE, outp);
+ pcb->eap.es_challen = EAP_MIN_CHALLENGE_LENGTH +
+ magic_pow(EAP_MIN_MAX_POWER_OF_TWO_CHALLENGE_LENGTH);
+ magic_random_bytes(pcb->eap.es_challenge, pcb->eap.es_challen);
+ MEMCPY(outp, pcb->eap.es_challenge, pcb->eap.es_challen);
+ INCPTR(pcb->eap.es_challen, outp);
+ break;
+#endif /* USE_SRP */
+
+ default:
+ return;
+ }
+
+ outlen = (outp - (unsigned char*)p->payload) - PPP_HDRLEN;
+ PUTSHORT(outlen, lenloc);
+
+ pbuf_realloc(p, outlen + PPP_HDRLEN);
+ ppp_write(pcb, p);
+
+ pcb->eap.es_server.ea_requests++;
+
+ if (pcb->settings.eap_timeout_time > 0)
+ TIMEOUT(eap_server_timeout, pcb, pcb->settings.eap_timeout_time);
+}
+
+/*
+ * eap_authpeer - Authenticate our peer (behave as server).
+ *
+ * Start server state and send first request. This is called only
+ * after eap_lowerup.
+ */
+void eap_authpeer(ppp_pcb *pcb, const char *localname) {
+
+ /* Save the name we're given. */
+ pcb->eap.es_server.ea_name = localname;
+ pcb->eap.es_server.ea_namelen = strlen(localname);
+
+ pcb->eap.es_savedtime = pcb->settings.eap_timeout_time;
+
+ /* Lower layer up yet? */
+ if (pcb->eap.es_server.ea_state == eapInitial ||
+ pcb->eap.es_server.ea_state == eapPending) {
+ pcb->eap.es_server.ea_state = eapPending;
+ return;
+ }
+
+ pcb->eap.es_server.ea_state = eapPending;
+
+ /* ID number not updated here intentionally; hashed into M1 */
+ eap_send_request(pcb);
+}
+
+/*
+ * eap_server_timeout - Retransmission timer for sending Requests
+ * expired.
+ */
+static void eap_server_timeout(void *arg) {
+ ppp_pcb *pcb = (ppp_pcb*)arg;
+
+ if (!eap_server_active(pcb))
+ return;
+
+ /* EAP ID number must not change on timeout. */
+ eap_send_request(pcb);
+}
+
+/*
+ * When it's time to send rechallenge the peer, this timeout is
+ * called. Once the rechallenge is successful, the response handler
+ * will restart the timer. If it fails, then the link is dropped.
+ */
+static void eap_rechallenge(void *arg) {
+ ppp_pcb *pcb = (ppp_pcb*)arg;
+
+ if (pcb->eap.es_server.ea_state != eapOpen &&
+ pcb->eap.es_server.ea_state != eapSRP4)
+ return;
+
+ pcb->eap.es_server.ea_requests = 0;
+ pcb->eap.es_server.ea_state = eapIdentify;
+ eap_figure_next_state(pcb, 0);
+ pcb->eap.es_server.ea_id++;
+ eap_send_request(pcb);
+}
+
+static void srp_lwrechallenge(void *arg) {
+ ppp_pcb *pcb = (ppp_pcb*)arg;
+
+ if (pcb->eap.es_server.ea_state != eapOpen ||
+ pcb->eap.es_server.ea_type != EAPT_SRP)
+ return;
+
+ pcb->eap.es_server.ea_requests = 0;
+ pcb->eap.es_server.ea_state = eapSRP4;
+ pcb->eap.es_server.ea_id++;
+ eap_send_request(pcb);
+}
+#endif /* PPP_SERVER */
+
+/*
+ * eap_lowerup - The lower layer is now up.
+ *
+ * This is called before either eap_authpeer or eap_authwithpeer. See
+ * link_established() in auth.c. All that's necessary here is to
+ * return to closed state so that those two routines will do the right
+ * thing.
+ */
+static void eap_lowerup(ppp_pcb *pcb) {
+ pcb->eap.es_client.ea_state = eapClosed;
+#if PPP_SERVER
+ pcb->eap.es_server.ea_state = eapClosed;
+#endif /* PPP_SERVER */
+}
+
+/*
+ * eap_lowerdown - The lower layer is now down.
+ *
+ * Cancel all timeouts and return to initial state.
+ */
+static void eap_lowerdown(ppp_pcb *pcb) {
+
+ if (eap_client_active(pcb) && pcb->settings.eap_req_time > 0) {
+ UNTIMEOUT(eap_client_timeout, pcb);
+ }
+#if PPP_SERVER
+ if (eap_server_active(pcb)) {
+ if (pcb->settings.eap_timeout_time > 0) {
+ UNTIMEOUT(eap_server_timeout, pcb);
+ }
+ } else {
+ if ((pcb->eap.es_server.ea_state == eapOpen ||
+ pcb->eap.es_server.ea_state == eapSRP4) &&
+ pcb->eap.es_rechallenge > 0) {
+ UNTIMEOUT(eap_rechallenge, (void *)pcb);
+ }
+ if (pcb->eap.es_server.ea_state == eapOpen &&
+ pcb->eap.es_lwrechallenge > 0) {
+ UNTIMEOUT(srp_lwrechallenge, (void *)pcb);
+ }
+ }
+
+ pcb->eap.es_client.ea_state = pcb->eap.es_server.ea_state = eapInitial;
+ pcb->eap.es_client.ea_requests = pcb->eap.es_server.ea_requests = 0;
+#endif /* PPP_SERVER */
+}
+
+/*
+ * eap_protrej - Peer doesn't speak this protocol.
+ *
+ * This shouldn't happen. If it does, it represents authentication
+ * failure.
+ */
+static void eap_protrej(ppp_pcb *pcb) {
+
+ if (eap_client_active(pcb)) {
+ ppp_error("EAP authentication failed due to Protocol-Reject");
+ auth_withpeer_fail(pcb, PPP_EAP);
+ }
+#if PPP_SERVER
+ if (eap_server_active(pcb)) {
+ ppp_error("EAP authentication of peer failed on Protocol-Reject");
+ auth_peer_fail(pcb, PPP_EAP);
+ }
+#endif /* PPP_SERVER */
+ eap_lowerdown(pcb);
+}
+
+/*
+ * Format and send a regular EAP Response message.
+ */
+static void eap_send_response(ppp_pcb *pcb, u_char id, u_char typenum, const u_char *str, int lenstr) {
+ struct pbuf *p;
+ u_char *outp;
+ int msglen;
+
+ msglen = EAP_HEADERLEN + sizeof (u_char) + lenstr;
+ p = pbuf_alloc(PBUF_RAW, (u16_t)(PPP_HDRLEN + msglen), PPP_CTRL_PBUF_TYPE);
+ if(NULL == p)
+ return;
+ if(p->tot_len != p->len) {
+ pbuf_free(p);
+ return;
+ }
+
+ outp = (u_char*)p->payload;
+
+ MAKEHEADER(outp, PPP_EAP);
+
+ PUTCHAR(EAP_RESPONSE, outp);
+ PUTCHAR(id, outp);
+ pcb->eap.es_client.ea_id = id;
+ PUTSHORT(msglen, outp);
+ PUTCHAR(typenum, outp);
+ if (lenstr > 0) {
+ MEMCPY(outp, str, lenstr);
+ }
+
+ ppp_write(pcb, p);
+}
+
+/*
+ * Format and send an MD5-Challenge EAP Response message.
+ */
+static void eap_chap_response(ppp_pcb *pcb, u_char id, u_char *hash, const char *name, int namelen) {
+ struct pbuf *p;
+ u_char *outp;
+ int msglen;
+
+ msglen = EAP_HEADERLEN + 2 * sizeof (u_char) + MD5_SIGNATURE_SIZE +
+ namelen;
+ p = pbuf_alloc(PBUF_RAW, (u16_t)(PPP_HDRLEN + msglen), PPP_CTRL_PBUF_TYPE);
+ if(NULL == p)
+ return;
+ if(p->tot_len != p->len) {
+ pbuf_free(p);
+ return;
+ }
+
+ outp = (u_char*)p->payload;
+
+ MAKEHEADER(outp, PPP_EAP);
+
+ PUTCHAR(EAP_RESPONSE, outp);
+ PUTCHAR(id, outp);
+ pcb->eap.es_client.ea_id = id;
+ PUTSHORT(msglen, outp);
+ PUTCHAR(EAPT_MD5CHAP, outp);
+ PUTCHAR(MD5_SIGNATURE_SIZE, outp);
+ MEMCPY(outp, hash, MD5_SIGNATURE_SIZE);
+ INCPTR(MD5_SIGNATURE_SIZE, outp);
+ if (namelen > 0) {
+ MEMCPY(outp, name, namelen);
+ }
+
+ ppp_write(pcb, p);
+}
+
+#ifdef USE_SRP
+/*
+ * Format and send a SRP EAP Response message.
+ */
+static void
+eap_srp_response(esp, id, subtypenum, str, lenstr)
+eap_state *esp;
+u_char id;
+u_char subtypenum;
+u_char *str;
+int lenstr;
+{
+ ppp_pcb *pcb = &ppp_pcb_list[pcb->eap.es_unit];
+ struct pbuf *p;
+ u_char *outp;
+ int msglen;
+
+ msglen = EAP_HEADERLEN + 2 * sizeof (u_char) + lenstr;
+ p = pbuf_alloc(PBUF_RAW, (u16_t)(PPP_HDRLEN + msglen), PPP_CTRL_PBUF_TYPE);
+ if(NULL == p)
+ return;
+ if(p->tot_len != p->len) {
+ pbuf_free(p);
+ return;
+ }
+
+ outp = p->payload;
+
+ MAKEHEADER(outp, PPP_EAP);
+
+ PUTCHAR(EAP_RESPONSE, outp);
+ PUTCHAR(id, outp);
+ pcb->eap.es_client.ea_id = id;
+ PUTSHORT(msglen, outp);
+ PUTCHAR(EAPT_SRP, outp);
+ PUTCHAR(subtypenum, outp);
+ if (lenstr > 0) {
+ MEMCPY(outp, str, lenstr);
+ }
+
+ ppp_write(pcb, p);
+}
+
+/*
+ * Format and send a SRP EAP Client Validator Response message.
+ */
+static void
+eap_srpval_response(esp, id, flags, str)
+eap_state *esp;
+u_char id;
+u32_t flags;
+u_char *str;
+{
+ ppp_pcb *pcb = &ppp_pcb_list[pcb->eap.es_unit];
+ struct pbuf *p;
+ u_char *outp;
+ int msglen;
+
+ msglen = EAP_HEADERLEN + 2 * sizeof (u_char) + sizeof (u32_t) +
+ SHA_DIGESTSIZE;
+ p = pbuf_alloc(PBUF_RAW, (u16_t)(PPP_HDRLEN + msglen), PPP_CTRL_PBUF_TYPE);
+ if(NULL == p)
+ return;
+ if(p->tot_len != p->len) {
+ pbuf_free(p);
+ return;
+ }
+
+ outp = p->payload;
+
+ MAKEHEADER(outp, PPP_EAP);
+
+ PUTCHAR(EAP_RESPONSE, outp);
+ PUTCHAR(id, outp);
+ pcb->eap.es_client.ea_id = id;
+ PUTSHORT(msglen, outp);
+ PUTCHAR(EAPT_SRP, outp);
+ PUTCHAR(EAPSRP_CVALIDATOR, outp);
+ PUTLONG(flags, outp);
+ MEMCPY(outp, str, SHA_DIGESTSIZE);
+
+ ppp_write(pcb, p);
+}
+#endif /* USE_SRP */
+
+static void eap_send_nak(ppp_pcb *pcb, u_char id, u_char type) {
+ struct pbuf *p;
+ u_char *outp;
+ int msglen;
+
+ msglen = EAP_HEADERLEN + 2 * sizeof (u_char);
+ p = pbuf_alloc(PBUF_RAW, (u16_t)(PPP_HDRLEN + msglen), PPP_CTRL_PBUF_TYPE);
+ if(NULL == p)
+ return;
+ if(p->tot_len != p->len) {
+ pbuf_free(p);
+ return;
+ }
+
+ outp = (u_char*)p->payload;
+
+ MAKEHEADER(outp, PPP_EAP);
+
+ PUTCHAR(EAP_RESPONSE, outp);
+ PUTCHAR(id, outp);
+ pcb->eap.es_client.ea_id = id;
+ PUTSHORT(msglen, outp);
+ PUTCHAR(EAPT_NAK, outp);
+ PUTCHAR(type, outp);
+
+ ppp_write(pcb, p);
+}
+
+#ifdef USE_SRP
+static char *
+name_of_pn_file()
+{
+ char *user, *path, *file;
+ struct passwd *pw;
+ size_t pl;
+ static bool pnlogged = 0;
+
+ pw = getpwuid(getuid());
+ if (pw == NULL || (user = pw->pw_dir) == NULL || user[0] == 0) {
+ errno = EINVAL;
+ return (NULL);
+ }
+ file = _PATH_PSEUDONYM;
+ pl = strlen(user) + strlen(file) + 2;
+ path = malloc(pl);
+ if (path == NULL)
+ return (NULL);
+ (void) slprintf(path, pl, "%s/%s", user, file);
+ if (!pnlogged) {
+ ppp_dbglog("pseudonym file: %s", path);
+ pnlogged = 1;
+ }
+ return (path);
+}
+
+static int
+open_pn_file(modebits)
+mode_t modebits;
+{
+ char *path;
+ int fd, err;
+
+ if ((path = name_of_pn_file()) == NULL)
+ return (-1);
+ fd = open(path, modebits, S_IRUSR | S_IWUSR);
+ err = errno;
+ free(path);
+ errno = err;
+ return (fd);
+}
+
+static void
+remove_pn_file()
+{
+ char *path;
+
+ if ((path = name_of_pn_file()) != NULL) {
+ (void) unlink(path);
+ (void) free(path);
+ }
+}
+
+static void
+write_pseudonym(esp, inp, len, id)
+eap_state *esp;
+u_char *inp;
+int len, id;
+{
+ u_char val;
+ u_char *datp, *digp;
+ SHA1_CTX ctxt;
+ u_char dig[SHA_DIGESTSIZE];
+ int dsize, fd, olen = len;
+
+ /*
+ * Do the decoding by working backwards. This eliminates the need
+ * to save the decoded output in a separate buffer.
+ */
+ val = id;
+ while (len > 0) {
+ if ((dsize = len % SHA_DIGESTSIZE) == 0)
+ dsize = SHA_DIGESTSIZE;
+ len -= dsize;
+ datp = inp + len;
+ SHA1Init(&ctxt);
+ SHA1Update(&ctxt, &val, 1);
+ SHA1Update(&ctxt, pcb->eap.es_client.ea_skey, SESSION_KEY_LEN);
+ if (len > 0) {
+ SHA1Update(&ctxt, datp, SHA_DIGESTSIZE);
+ } else {
+ SHA1Update(&ctxt, pcb->eap.es_client.ea_name,
+ pcb->eap.es_client.ea_namelen);
+ }
+ SHA1Final(dig, &ctxt);
+ for (digp = dig; digp < dig + SHA_DIGESTSIZE; digp++)
+ *datp++ ^= *digp;
+ }
+
+ /* Now check that the result is sane */
+ if (olen <= 0 || *inp + 1 > olen) {
+ ppp_dbglog("EAP: decoded pseudonym is unusable <%.*B>", olen, inp);
+ return;
+ }
+
+ /* Save it away */
+ fd = open_pn_file(O_WRONLY | O_CREAT | O_TRUNC);
+ if (fd < 0) {
+ ppp_dbglog("EAP: error saving pseudonym: %m");
+ return;
+ }
+ len = write(fd, inp + 1, *inp);
+ if (close(fd) != -1 && len == *inp) {
+ ppp_dbglog("EAP: saved pseudonym");
+ pcb->eap.es_usedpseudo = 0;
+ } else {
+ ppp_dbglog("EAP: failed to save pseudonym");
+ remove_pn_file();
+ }
+}
+#endif /* USE_SRP */
+
+/*
+ * eap_request - Receive EAP Request message (client mode).
+ */
+static void eap_request(ppp_pcb *pcb, u_char *inp, int id, int len) {
+ u_char typenum;
+ u_char vallen;
+ int secret_len;
+ char secret[MAXSECRETLEN];
+ char rhostname[MAXNAMELEN];
+ lwip_md5_context mdContext;
+ u_char hash[MD5_SIGNATURE_SIZE];
+#ifdef USE_SRP
+ struct t_client *tc;
+ struct t_num sval, gval, Nval, *Ap, Bval;
+ u_char vals[2];
+ SHA1_CTX ctxt;
+ u_char dig[SHA_DIGESTSIZE];
+ int fd;
+#endif /* USE_SRP */
+
+ /*
+ * Note: we update es_client.ea_id *only if* a Response
+ * message is being generated. Otherwise, we leave it the
+ * same for duplicate detection purposes.
+ */
+
+ pcb->eap.es_client.ea_requests++;
+ if (pcb->settings.eap_allow_req != 0 &&
+ pcb->eap.es_client.ea_requests > pcb->settings.eap_allow_req) {
+ ppp_info("EAP: received too many Request messages");
+ if (pcb->settings.eap_req_time > 0) {
+ UNTIMEOUT(eap_client_timeout, pcb);
+ }
+ auth_withpeer_fail(pcb, PPP_EAP);
+ return;
+ }
+
+ if (len <= 0) {
+ ppp_error("EAP: empty Request message discarded");
+ return;
+ }
+
+ GETCHAR(typenum, inp);
+ len--;
+
+ switch (typenum) {
+ case EAPT_IDENTITY:
+ if (len > 0)
+ ppp_info("EAP: Identity prompt \"%.*q\"", len, inp);
+#ifdef USE_SRP
+ if (pcb->eap.es_usepseudo &&
+ (pcb->eap.es_usedpseudo == 0 ||
+ (pcb->eap.es_usedpseudo == 1 &&
+ id == pcb->eap.es_client.ea_id))) {
+ pcb->eap.es_usedpseudo = 1;
+ /* Try to get a pseudonym */
+ if ((fd = open_pn_file(O_RDONLY)) >= 0) {
+ strcpy(rhostname, SRP_PSEUDO_ID);
+ len = read(fd, rhostname + SRP_PSEUDO_LEN,
+ sizeof (rhostname) - SRP_PSEUDO_LEN);
+ /* XXX NAI unsupported */
+ if (len > 0) {
+ eap_send_response(pcb, id, typenum,
+ rhostname, len + SRP_PSEUDO_LEN);
+ }
+ (void) close(fd);
+ if (len > 0)
+ break;
+ }
+ }
+ /* Stop using pseudonym now. */
+ if (pcb->eap.es_usepseudo && pcb->eap.es_usedpseudo != 2) {
+ remove_pn_file();
+ pcb->eap.es_usedpseudo = 2;
+ }
+#endif /* USE_SRP */
+ eap_send_response(pcb, id, typenum, (const u_char*)pcb->eap.es_client.ea_name,
+ pcb->eap.es_client.ea_namelen);
+ break;
+
+ case EAPT_NOTIFICATION:
+ if (len > 0)
+ ppp_info("EAP: Notification \"%.*q\"", len, inp);
+ eap_send_response(pcb, id, typenum, NULL, 0);
+ break;
+
+ case EAPT_NAK:
+ /*
+ * Avoid the temptation to send Response Nak in reply
+ * to Request Nak here. It can only lead to trouble.
+ */
+ ppp_warn("EAP: unexpected Nak in Request; ignored");
+ /* Return because we're waiting for something real. */
+ return;
+
+ case EAPT_MD5CHAP:
+ if (len < 1) {
+ ppp_error("EAP: received MD5-Challenge with no data");
+ /* Bogus request; wait for something real. */
+ return;
+ }
+ GETCHAR(vallen, inp);
+ len--;
+ if (vallen < 8 || vallen > len) {
+ ppp_error("EAP: MD5-Challenge with bad length %d (8..%d)",
+ vallen, len);
+ /* Try something better. */
+ eap_send_nak(pcb, id, EAPT_SRP);
+ break;
+ }
+
+ /* Not so likely to happen. */
+ if (vallen >= len + sizeof (rhostname)) {
+ ppp_dbglog("EAP: trimming really long peer name down");
+ MEMCPY(rhostname, inp + vallen, sizeof (rhostname) - 1);
+ rhostname[sizeof (rhostname) - 1] = '\0';
+ } else {
+ MEMCPY(rhostname, inp + vallen, len - vallen);
+ rhostname[len - vallen] = '\0';
+ }
+
+#if PPP_REMOTENAME
+ /* In case the remote doesn't give us his name. */
+ if (pcb->settings.explicit_remote ||
+ (pcb->settings.remote_name[0] != '\0' && vallen == len))
+ strlcpy(rhostname, pcb->settings.remote_name, sizeof (rhostname));
+#endif /* PPP_REMOTENAME */
+
+ /*
+ * Get the secret for authenticating ourselves with
+ * the specified host.
+ */
+ if (!get_secret(pcb, pcb->eap.es_client.ea_name,
+ rhostname, secret, &secret_len, 0)) {
+ ppp_dbglog("EAP: no MD5 secret for auth to %q", rhostname);
+ eap_send_nak(pcb, id, EAPT_SRP);
+ break;
+ }
+ lwip_md5_init(&mdContext);
+ lwip_md5_starts(&mdContext);
+ typenum = id;
+ lwip_md5_update(&mdContext, &typenum, 1);
+ lwip_md5_update(&mdContext, (u_char *)secret, secret_len);
+ BZERO(secret, sizeof (secret));
+ lwip_md5_update(&mdContext, inp, vallen);
+ lwip_md5_finish(&mdContext, hash);
+ lwip_md5_free(&mdContext);
+ eap_chap_response(pcb, id, hash, pcb->eap.es_client.ea_name,
+ pcb->eap.es_client.ea_namelen);
+ break;
+
+#ifdef USE_SRP
+ case EAPT_SRP:
+ if (len < 1) {
+ ppp_error("EAP: received empty SRP Request");
+ /* Bogus request; wait for something real. */
+ return;
+ }
+
+ /* Get subtype */
+ GETCHAR(vallen, inp);
+ len--;
+ switch (vallen) {
+ case EAPSRP_CHALLENGE:
+ tc = NULL;
+ if (pcb->eap.es_client.ea_session != NULL) {
+ tc = (struct t_client *)pcb->eap.es_client.
+ ea_session;
+ /*
+ * If this is a new challenge, then start
+ * over with a new client session context.
+ * Otherwise, just resend last response.
+ */
+ if (id != pcb->eap.es_client.ea_id) {
+ t_clientclose(tc);
+ pcb->eap.es_client.ea_session = NULL;
+ tc = NULL;
+ }
+ }
+ /* No session key just yet */
+ pcb->eap.es_client.ea_skey = NULL;
+ if (tc == NULL) {
+ int rhostnamelen;
+
+ GETCHAR(vallen, inp);
+ len--;
+ if (vallen >= len) {
+ ppp_error("EAP: badly-formed SRP Challenge"
+ " (name)");
+ /* Ignore badly-formed messages */
+ return;
+ }
+ MEMCPY(rhostname, inp, vallen);
+ rhostname[vallen] = '\0';
+ INCPTR(vallen, inp);
+ len -= vallen;
+
+ /*
+ * In case the remote doesn't give us his name,
+ * use configured name.
+ */
+ if (explicit_remote ||
+ (remote_name[0] != '\0' && vallen == 0)) {
+ strlcpy(rhostname, remote_name,
+ sizeof (rhostname));
+ }
+
+ rhostnamelen = (int)strlen(rhostname);
+ if (rhostnamelen > MAXNAMELEN) {
+ rhostnamelen = MAXNAMELEN;
+ }
+ MEMCPY(pcb->eap.es_client.ea_peer, rhostname, rhostnamelen);
+ pcb->eap.es_client.ea_peer[rhostnamelen] = '\0';
+ pcb->eap.es_client.ea_peerlen = rhostnamelen;
+
+ GETCHAR(vallen, inp);
+ len--;
+ if (vallen >= len) {
+ ppp_error("EAP: badly-formed SRP Challenge"
+ " (s)");
+ /* Ignore badly-formed messages */
+ return;
+ }
+ sval.data = inp;
+ sval.len = vallen;
+ INCPTR(vallen, inp);
+ len -= vallen;
+
+ GETCHAR(vallen, inp);
+ len--;
+ if (vallen > len) {
+ ppp_error("EAP: badly-formed SRP Challenge"
+ " (g)");
+ /* Ignore badly-formed messages */
+ return;
+ }
+ /* If no generator present, then use value 2 */
+ if (vallen == 0) {
+ gval.data = (u_char *)"\002";
+ gval.len = 1;
+ } else {
+ gval.data = inp;
+ gval.len = vallen;
+ }
+ INCPTR(vallen, inp);
+ len -= vallen;
+
+ /*
+ * If no modulus present, then use well-known
+ * value.
+ */
+ if (len == 0) {
+ Nval.data = (u_char *)wkmodulus;
+ Nval.len = sizeof (wkmodulus);
+ } else {
+ Nval.data = inp;
+ Nval.len = len;
+ }
+ tc = t_clientopen(pcb->eap.es_client.ea_name,
+ &Nval, &gval, &sval);
+ if (tc == NULL) {
+ eap_send_nak(pcb, id, EAPT_MD5CHAP);
+ break;
+ }
+ pcb->eap.es_client.ea_session = (void *)tc;
+
+ /* Add Challenge ID & type to verifier */
+ vals[0] = id;
+ vals[1] = EAPT_SRP;
+ t_clientaddexdata(tc, vals, 2);
+ }
+ Ap = t_clientgenexp(tc);
+ eap_srp_response(esp, id, EAPSRP_CKEY, Ap->data,
+ Ap->len);
+ break;
+
+ case EAPSRP_SKEY:
+ tc = (struct t_client *)pcb->eap.es_client.ea_session;
+ if (tc == NULL) {
+ ppp_warn("EAP: peer sent Subtype 2 without 1");
+ eap_send_nak(pcb, id, EAPT_MD5CHAP);
+ break;
+ }
+ if (pcb->eap.es_client.ea_skey != NULL) {
+ /*
+ * ID number should not change here. Warn
+ * if it does (but otherwise ignore).
+ */
+ if (id != pcb->eap.es_client.ea_id) {
+ ppp_warn("EAP: ID changed from %d to %d "
+ "in SRP Subtype 2 rexmit",
+ pcb->eap.es_client.ea_id, id);
+ }
+ } else {
+ if (get_srp_secret(pcb->eap.es_unit,
+ pcb->eap.es_client.ea_name,
+ pcb->eap.es_client.ea_peer, secret, 0) == 0) {
+ /*
+ * Can't work with this peer because
+ * the secret is missing. Just give
+ * up.
+ */
+ eap_send_nak(pcb, id, EAPT_MD5CHAP);
+ break;
+ }
+ Bval.data = inp;
+ Bval.len = len;
+ t_clientpasswd(tc, secret);
+ BZERO(secret, sizeof (secret));
+ pcb->eap.es_client.ea_skey =
+ t_clientgetkey(tc, &Bval);
+ if (pcb->eap.es_client.ea_skey == NULL) {
+ /* Server is rogue; stop now */
+ ppp_error("EAP: SRP server is rogue");
+ goto client_failure;
+ }
+ }
+ eap_srpval_response(esp, id, SRPVAL_EBIT,
+ t_clientresponse(tc));
+ break;
+
+ case EAPSRP_SVALIDATOR:
+ tc = (struct t_client *)pcb->eap.es_client.ea_session;
+ if (tc == NULL || pcb->eap.es_client.ea_skey == NULL) {
+ ppp_warn("EAP: peer sent Subtype 3 without 1/2");
+ eap_send_nak(pcb, id, EAPT_MD5CHAP);
+ break;
+ }
+ /*
+ * If we're already open, then this ought to be a
+ * duplicate. Otherwise, check that the server is
+ * who we think it is.
+ */
+ if (pcb->eap.es_client.ea_state == eapOpen) {
+ if (id != pcb->eap.es_client.ea_id) {
+ ppp_warn("EAP: ID changed from %d to %d "
+ "in SRP Subtype 3 rexmit",
+ pcb->eap.es_client.ea_id, id);
+ }
+ } else {
+ len -= sizeof (u32_t) + SHA_DIGESTSIZE;
+ if (len < 0 || t_clientverify(tc, inp +
+ sizeof (u32_t)) != 0) {
+ ppp_error("EAP: SRP server verification "
+ "failed");
+ goto client_failure;
+ }
+ GETLONG(pcb->eap.es_client.ea_keyflags, inp);
+ /* Save pseudonym if user wants it. */
+ if (len > 0 && pcb->eap.es_usepseudo) {
+ INCPTR(SHA_DIGESTSIZE, inp);
+ write_pseudonym(esp, inp, len, id);
+ }
+ }
+ /*
+ * We've verified our peer. We're now mostly done,
+ * except for waiting on the regular EAP Success
+ * message.
+ */
+ eap_srp_response(esp, id, EAPSRP_ACK, NULL, 0);
+ break;
+
+ case EAPSRP_LWRECHALLENGE:
+ if (len < 4) {
+ ppp_warn("EAP: malformed Lightweight rechallenge");
+ return;
+ }
+ SHA1Init(&ctxt);
+ vals[0] = id;
+ SHA1Update(&ctxt, vals, 1);
+ SHA1Update(&ctxt, pcb->eap.es_client.ea_skey,
+ SESSION_KEY_LEN);
+ SHA1Update(&ctxt, inp, len);
+ SHA1Update(&ctxt, pcb->eap.es_client.ea_name,
+ pcb->eap.es_client.ea_namelen);
+ SHA1Final(dig, &ctxt);
+ eap_srp_response(esp, id, EAPSRP_LWRECHALLENGE, dig,
+ SHA_DIGESTSIZE);
+ break;
+
+ default:
+ ppp_error("EAP: unknown SRP Subtype %d", vallen);
+ eap_send_nak(pcb, id, EAPT_MD5CHAP);
+ break;
+ }
+ break;
+#endif /* USE_SRP */
+
+ default:
+ ppp_info("EAP: unknown authentication type %d; Naking", typenum);
+ eap_send_nak(pcb, id, EAPT_SRP);
+ break;
+ }
+
+ if (pcb->settings.eap_req_time > 0) {
+ UNTIMEOUT(eap_client_timeout, pcb);
+ TIMEOUT(eap_client_timeout, pcb,
+ pcb->settings.eap_req_time);
+ }
+ return;
+
+#ifdef USE_SRP
+client_failure:
+ pcb->eap.es_client.ea_state = eapBadAuth;
+ if (pcb->settings.eap_req_time > 0) {
+ UNTIMEOUT(eap_client_timeout, (void *)esp);
+ }
+ pcb->eap.es_client.ea_session = NULL;
+ t_clientclose(tc);
+ auth_withpeer_fail(pcb, PPP_EAP);
+#endif /* USE_SRP */
+}
+
+#if PPP_SERVER
+/*
+ * eap_response - Receive EAP Response message (server mode).
+ */
+static void eap_response(ppp_pcb *pcb, u_char *inp, int id, int len) {
+ u_char typenum;
+ u_char vallen;
+ int secret_len;
+ char secret[MAXSECRETLEN];
+ char rhostname[MAXNAMELEN];
+ lwip_md5_context mdContext;
+ u_char hash[MD5_SIGNATURE_SIZE];
+#ifdef USE_SRP
+ struct t_server *ts;
+ struct t_num A;
+ SHA1_CTX ctxt;
+ u_char dig[SHA_DIGESTSIZE];
+#endif /* USE_SRP */
+
+ if (pcb->eap.es_server.ea_id != id) {
+ ppp_dbglog("EAP: discarding Response %d; expected ID %d", id,
+ pcb->eap.es_server.ea_id);
+ return;
+ }
+
+ pcb->eap.es_server.ea_responses++;
+
+ if (len <= 0) {
+ ppp_error("EAP: empty Response message discarded");
+ return;
+ }
+
+ GETCHAR(typenum, inp);
+ len--;
+
+ switch (typenum) {
+ case EAPT_IDENTITY:
+ if (pcb->eap.es_server.ea_state != eapIdentify) {
+ ppp_dbglog("EAP discarding unwanted Identify \"%.q\"", len,
+ inp);
+ break;
+ }
+ ppp_info("EAP: unauthenticated peer name \"%.*q\"", len, inp);
+ if (len > MAXNAMELEN) {
+ len = MAXNAMELEN;
+ }
+ MEMCPY(pcb->eap.es_server.ea_peer, inp, len);
+ pcb->eap.es_server.ea_peer[len] = '\0';
+ pcb->eap.es_server.ea_peerlen = len;
+ eap_figure_next_state(pcb, 0);
+ break;
+
+ case EAPT_NOTIFICATION:
+ ppp_dbglog("EAP unexpected Notification; response discarded");
+ break;
+
+ case EAPT_NAK:
+ if (len < 1) {
+ ppp_info("EAP: Nak Response with no suggested protocol");
+ eap_figure_next_state(pcb, 1);
+ break;
+ }
+
+ GETCHAR(vallen, inp);
+ len--;
+
+ if (
+#if PPP_REMOTENAME
+ !pcb->explicit_remote &&
+#endif /* PPP_REMOTENAME */
+ pcb->eap.es_server.ea_state == eapIdentify){
+ /* Peer cannot Nak Identify Request */
+ eap_figure_next_state(pcb, 1);
+ break;
+ }
+
+ switch (vallen) {
+ case EAPT_SRP:
+ /* Run through SRP validator selection again. */
+ pcb->eap.es_server.ea_state = eapIdentify;
+ eap_figure_next_state(pcb, 0);
+ break;
+
+ case EAPT_MD5CHAP:
+ pcb->eap.es_server.ea_state = eapMD5Chall;
+ break;
+
+ default:
+ ppp_dbglog("EAP: peer requesting unknown Type %d", vallen);
+ switch (pcb->eap.es_server.ea_state) {
+ case eapSRP1:
+ case eapSRP2:
+ case eapSRP3:
+ pcb->eap.es_server.ea_state = eapMD5Chall;
+ break;
+ case eapMD5Chall:
+ case eapSRP4:
+ pcb->eap.es_server.ea_state = eapIdentify;
+ eap_figure_next_state(pcb, 0);
+ break;
+ default:
+ break;
+ }
+ break;
+ }
+ break;
+
+ case EAPT_MD5CHAP:
+ if (pcb->eap.es_server.ea_state != eapMD5Chall) {
+ ppp_error("EAP: unexpected MD5-Response");
+ eap_figure_next_state(pcb, 1);
+ break;
+ }
+ if (len < 1) {
+ ppp_error("EAP: received MD5-Response with no data");
+ eap_figure_next_state(pcb, 1);
+ break;
+ }
+ GETCHAR(vallen, inp);
+ len--;
+ if (vallen != 16 || vallen > len) {
+ ppp_error("EAP: MD5-Response with bad length %d", vallen);
+ eap_figure_next_state(pcb, 1);
+ break;
+ }
+
+ /* Not so likely to happen. */
+ if (vallen >= len + sizeof (rhostname)) {
+ ppp_dbglog("EAP: trimming really long peer name down");
+ MEMCPY(rhostname, inp + vallen, sizeof (rhostname) - 1);
+ rhostname[sizeof (rhostname) - 1] = '\0';
+ } else {
+ MEMCPY(rhostname, inp + vallen, len - vallen);
+ rhostname[len - vallen] = '\0';
+ }
+
+#if PPP_REMOTENAME
+ /* In case the remote doesn't give us his name. */
+ if (explicit_remote ||
+ (remote_name[0] != '\0' && vallen == len))
+ strlcpy(rhostname, remote_name, sizeof (rhostname));
+#endif /* PPP_REMOTENAME */
+
+ /*
+ * Get the secret for authenticating the specified
+ * host.
+ */
+ if (!get_secret(pcb, rhostname,
+ pcb->eap.es_server.ea_name, secret, &secret_len, 1)) {
+ ppp_dbglog("EAP: no MD5 secret for auth of %q", rhostname);
+ eap_send_failure(pcb);
+ break;
+ }
+ lwip_md5_init(&mdContext);
+ lwip_md5_starts(&mdContext);
+ lwip_md5_update(&mdContext, &pcb->eap.es_server.ea_id, 1);
+ lwip_md5_update(&mdContext, (u_char *)secret, secret_len);
+ BZERO(secret, sizeof (secret));
+ lwip_md5_update(&mdContext, pcb->eap.es_challenge, pcb->eap.es_challen);
+ lwip_md5_finish(&mdContext, hash);
+ lwip_md5_free(&mdContext);
+ if (BCMP(hash, inp, MD5_SIGNATURE_SIZE) != 0) {
+ eap_send_failure(pcb);
+ break;
+ }
+ pcb->eap.es_server.ea_type = EAPT_MD5CHAP;
+ eap_send_success(pcb);
+ eap_figure_next_state(pcb, 0);
+ if (pcb->eap.es_rechallenge != 0)
+ TIMEOUT(eap_rechallenge, pcb, pcb->eap.es_rechallenge);
+ break;
+
+#ifdef USE_SRP
+ case EAPT_SRP:
+ if (len < 1) {
+ ppp_error("EAP: empty SRP Response");
+ eap_figure_next_state(pcb, 1);
+ break;
+ }
+ GETCHAR(typenum, inp);
+ len--;
+ switch (typenum) {
+ case EAPSRP_CKEY:
+ if (pcb->eap.es_server.ea_state != eapSRP1) {
+ ppp_error("EAP: unexpected SRP Subtype 1 Response");
+ eap_figure_next_state(pcb, 1);
+ break;
+ }
+ A.data = inp;
+ A.len = len;
+ ts = (struct t_server *)pcb->eap.es_server.ea_session;
+ assert(ts != NULL);
+ pcb->eap.es_server.ea_skey = t_servergetkey(ts, &A);
+ if (pcb->eap.es_server.ea_skey == NULL) {
+ /* Client's A value is bogus; terminate now */
+ ppp_error("EAP: bogus A value from client");
+ eap_send_failure(pcb);
+ } else {
+ eap_figure_next_state(pcb, 0);
+ }
+ break;
+
+ case EAPSRP_CVALIDATOR:
+ if (pcb->eap.es_server.ea_state != eapSRP2) {
+ ppp_error("EAP: unexpected SRP Subtype 2 Response");
+ eap_figure_next_state(pcb, 1);
+ break;
+ }
+ if (len < sizeof (u32_t) + SHA_DIGESTSIZE) {
+ ppp_error("EAP: M1 length %d < %d", len,
+ sizeof (u32_t) + SHA_DIGESTSIZE);
+ eap_figure_next_state(pcb, 1);
+ break;
+ }
+ GETLONG(pcb->eap.es_server.ea_keyflags, inp);
+ ts = (struct t_server *)pcb->eap.es_server.ea_session;
+ assert(ts != NULL);
+ if (t_serververify(ts, inp)) {
+ ppp_info("EAP: unable to validate client identity");
+ eap_send_failure(pcb);
+ break;
+ }
+ eap_figure_next_state(pcb, 0);
+ break;
+
+ case EAPSRP_ACK:
+ if (pcb->eap.es_server.ea_state != eapSRP3) {
+ ppp_error("EAP: unexpected SRP Subtype 3 Response");
+ eap_send_failure(esp);
+ break;
+ }
+ pcb->eap.es_server.ea_type = EAPT_SRP;
+ eap_send_success(pcb, esp);
+ eap_figure_next_state(pcb, 0);
+ if (pcb->eap.es_rechallenge != 0)
+ TIMEOUT(eap_rechallenge, pcb,
+ pcb->eap.es_rechallenge);
+ if (pcb->eap.es_lwrechallenge != 0)
+ TIMEOUT(srp_lwrechallenge, pcb,
+ pcb->eap.es_lwrechallenge);
+ break;
+
+ case EAPSRP_LWRECHALLENGE:
+ if (pcb->eap.es_server.ea_state != eapSRP4) {
+ ppp_info("EAP: unexpected SRP Subtype 4 Response");
+ return;
+ }
+ if (len != SHA_DIGESTSIZE) {
+ ppp_error("EAP: bad Lightweight rechallenge "
+ "response");
+ return;
+ }
+ SHA1Init(&ctxt);
+ vallen = id;
+ SHA1Update(&ctxt, &vallen, 1);
+ SHA1Update(&ctxt, pcb->eap.es_server.ea_skey,
+ SESSION_KEY_LEN);
+ SHA1Update(&ctxt, pcb->eap.es_challenge, pcb->eap.es_challen);
+ SHA1Update(&ctxt, pcb->eap.es_server.ea_peer,
+ pcb->eap.es_server.ea_peerlen);
+ SHA1Final(dig, &ctxt);
+ if (BCMP(dig, inp, SHA_DIGESTSIZE) != 0) {
+ ppp_error("EAP: failed Lightweight rechallenge");
+ eap_send_failure(pcb);
+ break;
+ }
+ pcb->eap.es_server.ea_state = eapOpen;
+ if (pcb->eap.es_lwrechallenge != 0)
+ TIMEOUT(srp_lwrechallenge, esp,
+ pcb->eap.es_lwrechallenge);
+ break;
+ }
+ break;
+#endif /* USE_SRP */
+
+ default:
+ /* This can't happen. */
+ ppp_error("EAP: unknown Response type %d; ignored", typenum);
+ return;
+ }
+
+ if (pcb->settings.eap_timeout_time > 0) {
+ UNTIMEOUT(eap_server_timeout, pcb);
+ }
+
+ if (pcb->eap.es_server.ea_state != eapBadAuth &&
+ pcb->eap.es_server.ea_state != eapOpen) {
+ pcb->eap.es_server.ea_id++;
+ eap_send_request(pcb);
+ }
+}
+#endif /* PPP_SERVER */
+
+/*
+ * eap_success - Receive EAP Success message (client mode).
+ */
+static void eap_success(ppp_pcb *pcb, u_char *inp, int id, int len) {
+ LWIP_UNUSED_ARG(id);
+
+ if (pcb->eap.es_client.ea_state != eapOpen && !eap_client_active(pcb)) {
+ ppp_dbglog("EAP unexpected success message in state %s (%d)",
+ eap_state_name(pcb->eap.es_client.ea_state),
+ pcb->eap.es_client.ea_state);
+ return;
+ }
+
+ if (pcb->settings.eap_req_time > 0) {
+ UNTIMEOUT(eap_client_timeout, pcb);
+ }
+
+ if (len > 0) {
+ /* This is odd. The spec doesn't allow for this. */
+ PRINTMSG(inp, len);
+ }
+
+ pcb->eap.es_client.ea_state = eapOpen;
+ auth_withpeer_success(pcb, PPP_EAP, 0);
+}
+
+/*
+ * eap_failure - Receive EAP Failure message (client mode).
+ */
+static void eap_failure(ppp_pcb *pcb, u_char *inp, int id, int len) {
+ LWIP_UNUSED_ARG(id);
+
+ if (!eap_client_active(pcb)) {
+ ppp_dbglog("EAP unexpected failure message in state %s (%d)",
+ eap_state_name(pcb->eap.es_client.ea_state),
+ pcb->eap.es_client.ea_state);
+ }
+
+ if (pcb->settings.eap_req_time > 0) {
+ UNTIMEOUT(eap_client_timeout, pcb);
+ }
+
+ if (len > 0) {
+ /* This is odd. The spec doesn't allow for this. */
+ PRINTMSG(inp, len);
+ }
+
+ pcb->eap.es_client.ea_state = eapBadAuth;
+
+ ppp_error("EAP: peer reports authentication failure");
+ auth_withpeer_fail(pcb, PPP_EAP);
+}
+
+/*
+ * eap_input - Handle received EAP message.
+ */
+static void eap_input(ppp_pcb *pcb, u_char *inp, int inlen) {
+ u_char code, id;
+ int len;
+
+ /*
+ * Parse header (code, id and length). If packet too short,
+ * drop it.
+ */
+ if (inlen < EAP_HEADERLEN) {
+ ppp_error("EAP: packet too short: %d < %d", inlen, EAP_HEADERLEN);
+ return;
+ }
+ GETCHAR(code, inp);
+ GETCHAR(id, inp);
+ GETSHORT(len, inp);
+ if (len < EAP_HEADERLEN || len > inlen) {
+ ppp_error("EAP: packet has illegal length field %d (%d..%d)", len,
+ EAP_HEADERLEN, inlen);
+ return;
+ }
+ len -= EAP_HEADERLEN;
+
+ /* Dispatch based on message code */
+ switch (code) {
+ case EAP_REQUEST:
+ eap_request(pcb, inp, id, len);
+ break;
+
+#if PPP_SERVER
+ case EAP_RESPONSE:
+ eap_response(pcb, inp, id, len);
+ break;
+#endif /* PPP_SERVER */
+
+ case EAP_SUCCESS:
+ eap_success(pcb, inp, id, len);
+ break;
+
+ case EAP_FAILURE:
+ eap_failure(pcb, inp, id, len);
+ break;
+
+ default: /* XXX Need code reject */
+ /* Note: it's not legal to send EAP Nak here. */
+ ppp_warn("EAP: unknown code %d received", code);
+ break;
+ }
+}
+
+#if PRINTPKT_SUPPORT
+/*
+ * eap_printpkt - print the contents of an EAP packet.
+ */
+static const char* const eap_codenames[] = {
+ "Request", "Response", "Success", "Failure"
+};
+
+static const char* const eap_typenames[] = {
+ "Identity", "Notification", "Nak", "MD5-Challenge",
+ "OTP", "Generic-Token", NULL, NULL,
+ "RSA", "DSS", "KEA", "KEA-Validate",
+ "TLS", "Defender", "Windows 2000", "Arcot",
+ "Cisco", "Nokia", "SRP"
+};
+
+static int eap_printpkt(const u_char *inp, int inlen, void (*printer) (void *, const char *, ...), void *arg) {
+ int code, id, len, rtype, vallen;
+ const u_char *pstart;
+ u32_t uval;
+
+ if (inlen < EAP_HEADERLEN)
+ return (0);
+ pstart = inp;
+ GETCHAR(code, inp);
+ GETCHAR(id, inp);
+ GETSHORT(len, inp);
+ if (len < EAP_HEADERLEN || len > inlen)
+ return (0);
+
+ if (code >= 1 && code <= (int)LWIP_ARRAYSIZE(eap_codenames))
+ printer(arg, " %s", eap_codenames[code-1]);
+ else
+ printer(arg, " code=0x%x", code);
+ printer(arg, " id=0x%x", id);
+ len -= EAP_HEADERLEN;
+ switch (code) {
+ case EAP_REQUEST:
+ if (len < 1) {
+ printer(arg, " <missing type>");
+ break;
+ }
+ GETCHAR(rtype, inp);
+ len--;
+ if (rtype >= 1 && rtype <= (int)LWIP_ARRAYSIZE(eap_typenames))
+ printer(arg, " %s", eap_typenames[rtype-1]);
+ else
+ printer(arg, " type=0x%x", rtype);
+ switch (rtype) {
+ case EAPT_IDENTITY:
+ case EAPT_NOTIFICATION:
+ if (len > 0) {
+ printer(arg, " <Message ");
+ ppp_print_string(inp, len, printer, arg);
+ printer(arg, ">");
+ INCPTR(len, inp);
+ len = 0;
+ } else {
+ printer(arg, " <No message>");
+ }
+ break;
+
+ case EAPT_MD5CHAP:
+ if (len <= 0)
+ break;
+ GETCHAR(vallen, inp);
+ len--;
+ if (vallen > len)
+ goto truncated;
+ printer(arg, " <Value%.*B>", vallen, inp);
+ INCPTR(vallen, inp);
+ len -= vallen;
+ if (len > 0) {
+ printer(arg, " <Name ");
+ ppp_print_string(inp, len, printer, arg);
+ printer(arg, ">");
+ INCPTR(len, inp);
+ len = 0;
+ } else {
+ printer(arg, " <No name>");
+ }
+ break;
+
+ case EAPT_SRP:
+ if (len < 3)
+ goto truncated;
+ GETCHAR(vallen, inp);
+ len--;
+ printer(arg, "-%d", vallen);
+ switch (vallen) {
+ case EAPSRP_CHALLENGE:
+ GETCHAR(vallen, inp);
+ len--;
+ if (vallen >= len)
+ goto truncated;
+ if (vallen > 0) {
+ printer(arg, " <Name ");
+ ppp_print_string(inp, vallen, printer,
+ arg);
+ printer(arg, ">");
+ } else {
+ printer(arg, " <No name>");
+ }
+ INCPTR(vallen, inp);
+ len -= vallen;
+ GETCHAR(vallen, inp);
+ len--;
+ if (vallen >= len)
+ goto truncated;
+ printer(arg, " <s%.*B>", vallen, inp);
+ INCPTR(vallen, inp);
+ len -= vallen;
+ GETCHAR(vallen, inp);
+ len--;
+ if (vallen > len)
+ goto truncated;
+ if (vallen == 0) {
+ printer(arg, " <Default g=2>");
+ } else {
+ printer(arg, " <g%.*B>", vallen, inp);
+ }
+ INCPTR(vallen, inp);
+ len -= vallen;
+ if (len == 0) {
+ printer(arg, " <Default N>");
+ } else {
+ printer(arg, " <N%.*B>", len, inp);
+ INCPTR(len, inp);
+ len = 0;
+ }
+ break;
+
+ case EAPSRP_SKEY:
+ printer(arg, " <B%.*B>", len, inp);
+ INCPTR(len, inp);
+ len = 0;
+ break;
+
+ case EAPSRP_SVALIDATOR:
+ if (len < (int)sizeof (u32_t))
+ break;
+ GETLONG(uval, inp);
+ len -= sizeof (u32_t);
+ if (uval & SRPVAL_EBIT) {
+ printer(arg, " E");
+ uval &= ~SRPVAL_EBIT;
+ }
+ if (uval != 0) {
+ printer(arg, " f<%X>", uval);
+ }
+ if ((vallen = len) > SHA_DIGESTSIZE)
+ vallen = SHA_DIGESTSIZE;
+ printer(arg, " <M2%.*B%s>", len, inp,
+ len < SHA_DIGESTSIZE ? "?" : "");
+ INCPTR(vallen, inp);
+ len -= vallen;
+ if (len > 0) {
+ printer(arg, " <PN%.*B>", len, inp);
+ INCPTR(len, inp);
+ len = 0;
+ }
+ break;
+
+ case EAPSRP_LWRECHALLENGE:
+ printer(arg, " <Challenge%.*B>", len, inp);
+ INCPTR(len, inp);
+ len = 0;
+ break;
+ default:
+ break;
+ }
+ break;
+ default:
+ break;
+ }
+ break;
+
+ case EAP_RESPONSE:
+ if (len < 1)
+ break;
+ GETCHAR(rtype, inp);
+ len--;
+ if (rtype >= 1 && rtype <= (int)LWIP_ARRAYSIZE(eap_typenames))
+ printer(arg, " %s", eap_typenames[rtype-1]);
+ else
+ printer(arg, " type=0x%x", rtype);
+ switch (rtype) {
+ case EAPT_IDENTITY:
+ if (len > 0) {
+ printer(arg, " <Name ");
+ ppp_print_string(inp, len, printer, arg);
+ printer(arg, ">");
+ INCPTR(len, inp);
+ len = 0;
+ }
+ break;
+
+ case EAPT_NAK:
+ if (len <= 0) {
+ printer(arg, " <missing hint>");
+ break;
+ }
+ GETCHAR(rtype, inp);
+ len--;
+ printer(arg, " <Suggested-type %02X", rtype);
+ if (rtype >= 1 && rtype < (int)LWIP_ARRAYSIZE(eap_typenames))
+ printer(arg, " (%s)", eap_typenames[rtype-1]);
+ printer(arg, ">");
+ break;
+
+ case EAPT_MD5CHAP:
+ if (len <= 0) {
+ printer(arg, " <missing length>");
+ break;
+ }
+ GETCHAR(vallen, inp);
+ len--;
+ if (vallen > len)
+ goto truncated;
+ printer(arg, " <Value%.*B>", vallen, inp);
+ INCPTR(vallen, inp);
+ len -= vallen;
+ if (len > 0) {
+ printer(arg, " <Name ");
+ ppp_print_string(inp, len, printer, arg);
+ printer(arg, ">");
+ INCPTR(len, inp);
+ len = 0;
+ } else {
+ printer(arg, " <No name>");
+ }
+ break;
+
+ case EAPT_SRP:
+ if (len < 1)
+ goto truncated;
+ GETCHAR(vallen, inp);
+ len--;
+ printer(arg, "-%d", vallen);
+ switch (vallen) {
+ case EAPSRP_CKEY:
+ printer(arg, " <A%.*B>", len, inp);
+ INCPTR(len, inp);
+ len = 0;
+ break;
+
+ case EAPSRP_CVALIDATOR:
+ if (len < (int)sizeof (u32_t))
+ break;
+ GETLONG(uval, inp);
+ len -= sizeof (u32_t);
+ if (uval & SRPVAL_EBIT) {
+ printer(arg, " E");
+ uval &= ~SRPVAL_EBIT;
+ }
+ if (uval != 0) {
+ printer(arg, " f<%X>", uval);
+ }
+ printer(arg, " <M1%.*B%s>", len, inp,
+ len == SHA_DIGESTSIZE ? "" : "?");
+ INCPTR(len, inp);
+ len = 0;
+ break;
+
+ case EAPSRP_ACK:
+ break;
+
+ case EAPSRP_LWRECHALLENGE:
+ printer(arg, " <Response%.*B%s>", len, inp,
+ len == SHA_DIGESTSIZE ? "" : "?");
+ if ((vallen = len) > SHA_DIGESTSIZE)
+ vallen = SHA_DIGESTSIZE;
+ INCPTR(vallen, inp);
+ len -= vallen;
+ break;
+ default:
+ break;
+ }
+ break;
+ default:
+ break;
+ }
+ break;
+
+ case EAP_SUCCESS: /* No payload expected for these! */
+ case EAP_FAILURE:
+ default:
+ break;
+
+ truncated:
+ printer(arg, " <truncated>");
+ break;
+ }
+
+ if (len > 8)
+ printer(arg, "%8B...", inp);
+ else if (len > 0)
+ printer(arg, "%.*B", len, inp);
+ INCPTR(len, inp);
+
+ return (inp - pstart);
+}
+#endif /* PRINTPKT_SUPPORT */
+
+#endif /* PPP_SUPPORT && EAP_SUPPORT */