[radsecproxy.git] / radsecproxy.c

/*
 * Copyright (C) 2006, 2007 Stig Venaas <venaas@uninett.no>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 */

/* For UDP there is one server instance consisting of udpserverrd and udpserverth
 *              rd is responsible for init and launching wr
 * For TLS there is a server instance that launches tlsserverrd for each TLS peer
 *          each tlsserverrd launches tlsserverwr
 * For each UDP/TLS peer there is clientrd and clientwr, clientwr is responsible
 *          for init and launching rd
 *
 * serverrd will receive a request, processes it and puts it in the requestq of
 *          the appropriate clientwr
 * clientwr monitors its requestq and sends requests
 * clientrd looks for responses, processes them and puts them in the replyq of
 *          the peer the request came from
 * serverwr monitors its reply and sends replies
 *
 * In addition to the main thread, we have:
 * If UDP peers are configured, there will be 2 + 2 * #peers UDP threads
 * If TLS peers are configured, there will initially be 2 * #peers TLS threads
 * For each TLS peer connecting to us there will be 2 more TLS threads
 *       This is only for connected peers
 * Example: With 3 UDP peer and 30 TLS peers, there will be a max of
 *          1 + (2 + 2 * 3) + (2 * 30) + (2 * 30) = 129 threads
*/

#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <string.h>
#include <unistd.h>
#include <sys/time.h>
#include <regex.h>
#include <libgen.h>
#include <pthread.h>
#include <openssl/ssl.h>
#include <openssl/rand.h>
#include <openssl/err.h>
#include <openssl/md5.h>
#include <openssl/hmac.h>
#include "debug.h"
#include "radsecproxy.h"

static struct options options;
static struct client *clients = NULL;
static struct server *servers = NULL;
static struct realm *realms = NULL;
static struct tls *tls = NULL;

static int client_udp_count = 0;
static int client_tls_count = 0;
static int client_count = 0;
static int server_udp_count = 0;
static int server_tls_count = 0;
static int server_count = 0;
static int realm_count = 0;
static int tls_count = 0;

static struct peer *tcp_server_listen;
static struct peer *udp_server_listen;
static struct replyq udp_server_replyq;
static int udp_server_sock = -1;
static pthread_mutex_t *ssl_locks;
static long *ssl_lock_count;
extern int optind;
extern char *optarg;

/* callbacks for making OpenSSL thread safe */
unsigned long ssl_thread_id() {
        return (unsigned long)pthread_self();
}

void ssl_locking_callback(int mode, int type, const char *file, int line) {
    if (mode & CRYPTO_LOCK) {
        pthread_mutex_lock(&ssl_locks[type]);
        ssl_lock_count[type]++;
    } else
        pthread_mutex_unlock(&ssl_locks[type]);
}

static int pem_passwd_cb(char *buf, int size, int rwflag, void *userdata) {
    int pwdlen = strlen(userdata);
    if (rwflag != 0 || pwdlen > size) /* not for decryption or too large */
        return 0;
    memcpy(buf, userdata, pwdlen);
    return pwdlen;
}

static int verify_cb(int ok, X509_STORE_CTX *ctx) {
  char buf[256];
  X509 *err_cert;
  int err, depth;

  err_cert = X509_STORE_CTX_get_current_cert(ctx);
  err = X509_STORE_CTX_get_error(ctx);
  depth = X509_STORE_CTX_get_error_depth(ctx);

  if (depth > MAX_CERT_DEPTH) {
      ok = 0;
      err = X509_V_ERR_CERT_CHAIN_TOO_LONG;
      X509_STORE_CTX_set_error(ctx, err);
  }

  if (!ok) {
      X509_NAME_oneline(X509_get_subject_name(err_cert), buf, 256);
      debug(DBG_WARN, "verify error: num=%d:%s:depth=%d:%s", err, X509_verify_cert_error_string(err), depth, buf);

      switch (err) {
      case X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT:
          X509_NAME_oneline(X509_get_issuer_name(ctx->current_cert), buf, 256);
          debug(DBG_WARN, "\tIssuer=%s", buf);
          break;
      case X509_V_ERR_CERT_NOT_YET_VALID:
      case X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD:
          debug(DBG_WARN, "\tCertificate not yet valid");
          break;
      case X509_V_ERR_CERT_HAS_EXPIRED:
          debug(DBG_WARN, "Certificate has expired");
          break;
      case X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD:
          debug(DBG_WARN, "Certificate no longer valid (after notAfter)");
          break;
      }
  }
#ifdef DEBUG  
  printf("certificate verify returns %d\n", ok);
#endif  
  return ok;
}

#ifdef DEBUG
void printauth(char *s, unsigned char *t) {
    int i;
    printf("%s:", s);
    for (i = 0; i < 16; i++)
            printf("%02x ", t[i]);
    printf("\n");
}
#endif

int resolvepeer(struct peer *peer, int ai_flags) {
    struct addrinfo hints, *addrinfo;
    
    memset(&hints, 0, sizeof(hints));
    hints.ai_socktype = (peer->type == 'T' ? SOCK_STREAM : SOCK_DGRAM);
    hints.ai_family = AF_UNSPEC;
    hints.ai_flags = ai_flags;
    if (getaddrinfo(peer->host, peer->port, &hints, &addrinfo)) {
        debug(DBG_WARN, "resolvepeer: can't resolve %s port %s", peer->host, peer->port);
        return 0;
    }

    if (peer->addrinfo)
        freeaddrinfo(peer->addrinfo);
    peer->addrinfo = addrinfo;
    return 1;
}         

int connecttoserver(struct addrinfo *addrinfo) {
    int s;
    struct addrinfo *res;

    s = -1;
    for (res = addrinfo; res; res = res->ai_next) {
        s = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
        if (s < 0) {
            debug(DBG_WARN, "connecttoserver: socket failed");
            continue;
        }
        if (connect(s, res->ai_addr, res->ai_addrlen) == 0)
            break;
        debug(DBG_WARN, "connecttoserver: connect failed");
        close(s);
        s = -1;
    }
    return s;
}         

int bindtoaddr(struct addrinfo *addrinfo) {
    int s, on = 1;
    struct addrinfo *res;
    
    for (res = addrinfo; res; res = res->ai_next) {
        s = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
        if (s < 0) {
            debug(DBG_WARN, "bindtoaddr: socket failed");
            continue;
        }
        setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
        if (!bind(s, res->ai_addr, res->ai_addrlen))
            return s;
        debug(DBG_WARN, "bindtoaddr: bind failed");
        close(s);
    }
    return -1;
}         

/* returns the client with matching address, or NULL */
/* if client argument is not NULL, we only check that one client */
struct client *find_client(char type, struct sockaddr *addr, struct client *client) {
    struct sockaddr_in6 *sa6 = NULL;
    struct in_addr *a4 = NULL;
    struct client *c;
    int i;
    struct addrinfo *res;

    if (addr->sa_family == AF_INET6) {
        sa6 = (struct sockaddr_in6 *)addr;
        if (IN6_IS_ADDR_V4MAPPED(&sa6->sin6_addr))
            a4 = (struct in_addr *)&sa6->sin6_addr.s6_addr[12];
    } else
        a4 = &((struct sockaddr_in *)addr)->sin_addr;

    c = (client ? client : clients);
    for (i = 0; i < client_count; i++) {
        if (c->peer.type == type)
            for (res = c->peer.addrinfo; res; res = res->ai_next)
                if ((a4 && res->ai_family == AF_INET &&
                     !memcmp(a4, &((struct sockaddr_in *)res->ai_addr)->sin_addr, 4)) ||
                    (sa6 && res->ai_family == AF_INET6 &&
                     !memcmp(&sa6->sin6_addr, &((struct sockaddr_in6 *)res->ai_addr)->sin6_addr, 16)))
                    return c;
        if (client)
            break;
        c++;
    }
    return NULL;
}

/* returns the server with matching address, or NULL */
/* if server argument is not NULL, we only check that one server */
struct server *find_server(char type, struct sockaddr *addr, struct server *server) {
    struct sockaddr_in6 *sa6 = NULL;
    struct in_addr *a4 = NULL;
    struct server *s;
    int i;
    struct addrinfo *res;

    if (addr->sa_family == AF_INET6) {
        sa6 = (struct sockaddr_in6 *)addr;
        if (IN6_IS_ADDR_V4MAPPED(&sa6->sin6_addr))
            a4 = (struct in_addr *)&sa6->sin6_addr.s6_addr[12];
    } else
        a4 = &((struct sockaddr_in *)addr)->sin_addr;

    s = (server ? server : servers);
    for (i = 0; i < server_count; i++) {
        if (s->peer.type == type)
            for (res = s->peer.addrinfo; res; res = res->ai_next)
                if ((a4 && res->ai_family == AF_INET &&
                     !memcmp(a4, &((struct sockaddr_in *)res->ai_addr)->sin_addr, 4)) ||
                    (sa6 && res->ai_family == AF_INET6 &&
                     !memcmp(&sa6->sin6_addr, &((struct sockaddr_in6 *)res->ai_addr)->sin6_addr, 16)))
                    return s;
        if (server)
            break;
        s++;
    }
    return NULL;
}

/* exactly one of client and server must be non-NULL */
/* if *peer == NULL we return who we received from, else require it to be from peer */
/* return from in sa if not NULL */
unsigned char *radudpget(int s, struct client **client, struct server **server, struct sockaddr_storage *sa) {
    int cnt, len;
    void *f;
    unsigned char buf[65536], *rad;
    struct sockaddr_storage from;
    socklen_t fromlen = sizeof(from);

    for (;;) {
        cnt = recvfrom(s, buf, sizeof(buf), 0, (struct sockaddr *)&from, &fromlen);
        if (cnt == -1) {
            debug(DBG_WARN, "radudpget: recv failed");
            continue;
        }
        debug(DBG_DBG, "radudpget: got %d bytes from %s", cnt, addr2string((struct sockaddr *)&from, fromlen));

        if (cnt < 20) {
            debug(DBG_WARN, "radudpget: packet too small");
            continue;
        }
    
        len = RADLEN(buf);
        if (len < 20) {
            debug(DBG_WARN, "radudpget: length too small");
            continue;
        }

        if (cnt < len) {
            debug(DBG_WARN, "radudpget: packet smaller than length field in radius header");
            continue;
        }
        if (cnt > len)
            debug(DBG_DBG, "radudpget: packet was padded with %d bytes", cnt - len);

        f = (client
             ? (void *)find_client('U', (struct sockaddr *)&from, *client)
             : (void *)find_server('U', (struct sockaddr *)&from, *server));
        if (!f) {
            debug(DBG_WARN, "radudpget: got packet from wrong or unknown UDP peer, ignoring");
            continue;
        }

        rad = malloc(len);
        if (rad)
            break;
        debug(DBG_ERR, "radudpget: malloc failed");
    }
    memcpy(rad, buf, len);
    if (client)
        *client = (struct client *)f; /* only need this if *client == NULL, but if not NULL *client == f here */
    else
        *server = (struct server *)f; /* only need this if *server == NULL, but if not NULL *server == f here */
    if (sa)
        *sa = from;
    return rad;
}

int tlsverifycert(struct peer *peer) {
    int l, loc;
    X509 *cert;
    X509_NAME *nm;
    X509_NAME_ENTRY *e;
    unsigned char *v;
    unsigned long error;

    if (SSL_get_verify_result(peer->ssl) != X509_V_OK) {
        debug(DBG_ERR, "tlsverifycert: basic validation failed");
        while ((error = ERR_get_error()))
            debug(DBG_ERR, "tlsverifycert: TLS: %s", ERR_error_string(error, NULL));
        return 0;
    }

    cert = SSL_get_peer_certificate(peer->ssl);
    if (!cert) {
        debug(DBG_ERR, "tlsverifycert: failed to obtain certificate");
        return 0;
    }
    nm = X509_get_subject_name(cert);
    loc = -1;
    for (;;) {
        loc = X509_NAME_get_index_by_NID(nm, NID_commonName, loc);
        if (loc == -1)
            break;
        e = X509_NAME_get_entry(nm, loc);
        l = ASN1_STRING_to_UTF8(&v, X509_NAME_ENTRY_get_data(e));
        if (l < 0)
            continue;
#ifdef DEBUG
        {
            int i;
            printf("cn: ");
            for (i = 0; i < l; i++)
                printf("%c", v[i]);
            printf("\n");
        }
#endif  
        if (l == strlen(peer->host) && !strncasecmp(peer->host, (char *)v, l)) {
            debug(DBG_DBG, "tlsverifycert: Found cn matching host %s, All OK", peer->host);
            return 1;
        }
        debug(DBG_ERR, "tlsverifycert: cn not matching host %s", peer->host);
    }
    X509_free(cert);
    return 0;
}

void tlsconnect(struct server *server, struct timeval *when, char *text) {
    struct timeval now;
    time_t elapsed;

    debug(DBG_DBG, "tlsconnect called from %s", text);
    pthread_mutex_lock(&server->lock);
    if (when && memcmp(&server->lastconnecttry, when, sizeof(struct timeval))) {
        /* already reconnected, nothing to do */
        debug(DBG_DBG, "tlsconnect(%s): seems already reconnected", text);
        pthread_mutex_unlock(&server->lock);
        return;
    }

    debug(DBG_DBG, "tlsconnect %s", text);

    for (;;) {
        gettimeofday(&now, NULL);
        elapsed = now.tv_sec - server->lastconnecttry.tv_sec;
        if (server->connectionok) {
            server->connectionok = 0;
            sleep(10);
        } else if (elapsed < 5)
            sleep(10);
        else if (elapsed < 300) {
            debug(DBG_INFO, "tlsconnect: sleeping %lds", elapsed);
            sleep(elapsed);
        } else if (elapsed < 100000) {
            debug(DBG_INFO, "tlsconnect: sleeping %ds", 600);
            sleep(600);
        } else
            server->lastconnecttry.tv_sec = now.tv_sec;  /* no sleep at startup */
        debug(DBG_WARN, "tlsconnect: trying to open TLS connection to %s port %s", server->peer.host, server->peer.port);
        if (server->sock >= 0)
            close(server->sock);
        if ((server->sock = connecttoserver(server->peer.addrinfo)) < 0) {
            debug(DBG_ERR, "tlsconnect: connecttoserver failed");
            continue;
        }
        
        SSL_free(server->peer.ssl);
        server->peer.ssl = SSL_new(server->peer.ssl_ctx);
        SSL_set_fd(server->peer.ssl, server->sock);
        if (SSL_connect(server->peer.ssl) > 0 && tlsverifycert(&server->peer))
            break;
    }
    debug(DBG_WARN, "tlsconnect: TLS connection to %s port %s up", server->peer.host, server->peer.port);
    gettimeofday(&server->lastconnecttry, NULL);
    pthread_mutex_unlock(&server->lock);
}

unsigned char *radtlsget(SSL *ssl) {
    int cnt, total, len;
    unsigned char buf[4], *rad;

    for (;;) {
        for (total = 0; total < 4; total += cnt) {
            cnt = SSL_read(ssl, buf + total, 4 - total);
            if (cnt <= 0) {
                debug(DBG_ERR, "radtlsget: connection lost");
                if (SSL_get_error(ssl, cnt) == SSL_ERROR_ZERO_RETURN) {
                    /* remote end sent close_notify, send one back */
                    SSL_shutdown(ssl);
                }
                return NULL;
            }
        }

        len = RADLEN(buf);
        rad = malloc(len);
        if (!rad) {
            debug(DBG_ERR, "radtlsget: malloc failed");
            continue;
        }
        memcpy(rad, buf, 4);

        for (; total < len; total += cnt) {
            cnt = SSL_read(ssl, rad + total, len - total);
            if (cnt <= 0) {
                debug(DBG_ERR, "radtlsget: connection lost");
                if (SSL_get_error(ssl, cnt) == SSL_ERROR_ZERO_RETURN) {
                    /* remote end sent close_notify, send one back */
                    SSL_shutdown(ssl);
                }
                free(rad);
                return NULL;
            }
        }
    
        if (total >= 20)
            break;
        
        free(rad);
        debug(DBG_WARN, "radtlsget: packet smaller than minimum radius size");
    }
    
    debug(DBG_DBG, "radtlsget: got %d bytes", total);
    return rad;
}

int clientradput(struct server *server, unsigned char *rad) {
    int cnt;
    size_t len;
    unsigned long error;
    struct timeval lastconnecttry;
    
    len = RADLEN(rad);
    if (server->peer.type == 'U') {
        if (send(server->sock, rad, len, 0) >= 0) {
            debug(DBG_DBG, "clienradput: sent UDP of length %d to %s port %s", len, server->peer.host, server->peer.port);
            return 1;
        }
        debug(DBG_WARN, "clientradput: send failed");
        return 0;
    }

    lastconnecttry = server->lastconnecttry;
    while ((cnt = SSL_write(server->peer.ssl, rad, len)) <= 0) {
        while ((error = ERR_get_error()))
            debug(DBG_ERR, "clientradput: TLS: %s", ERR_error_string(error, NULL));
        tlsconnect(server, &lastconnecttry, "clientradput");
        lastconnecttry = server->lastconnecttry;
    }

    server->connectionok = 1;
    debug(DBG_DBG, "clientradput: Sent %d bytes, Radius packet of length %d to TLS peer %s",
           cnt, len, server->peer.host);
    return 1;
}

int radsign(unsigned char *rad, unsigned char *sec) {
    static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
    static unsigned char first = 1;
    static EVP_MD_CTX mdctx;
    unsigned int md_len;
    int result;
    
    pthread_mutex_lock(&lock);
    if (first) {
        EVP_MD_CTX_init(&mdctx);
        first = 0;
    }

    result = (EVP_DigestInit_ex(&mdctx, EVP_md5(), NULL) &&
        EVP_DigestUpdate(&mdctx, rad, RADLEN(rad)) &&
        EVP_DigestUpdate(&mdctx, sec, strlen((char *)sec)) &&
        EVP_DigestFinal_ex(&mdctx, rad + 4, &md_len) &&
        md_len == 16);
    pthread_mutex_unlock(&lock);
    return result;
}

int validauth(unsigned char *rad, unsigned char *reqauth, unsigned char *sec) {
    static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
    static unsigned char first = 1;
    static EVP_MD_CTX mdctx;
    unsigned char hash[EVP_MAX_MD_SIZE];
    unsigned int len;
    int result;
    
    pthread_mutex_lock(&lock);
    if (first) {
        EVP_MD_CTX_init(&mdctx);
        first = 0;
    }

    len = RADLEN(rad);
    
    result = (EVP_DigestInit_ex(&mdctx, EVP_md5(), NULL) &&
              EVP_DigestUpdate(&mdctx, rad, 4) &&
              EVP_DigestUpdate(&mdctx, reqauth, 16) &&
              (len <= 20 || EVP_DigestUpdate(&mdctx, rad + 20, len - 20)) &&
              EVP_DigestUpdate(&mdctx, sec, strlen((char *)sec)) &&
              EVP_DigestFinal_ex(&mdctx, hash, &len) &&
              len == 16 &&
              !memcmp(hash, rad + 4, 16));
    pthread_mutex_unlock(&lock);
    return result;
}
              
int checkmessageauth(unsigned char *rad, uint8_t *authattr, char *secret) {
    static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
    static unsigned char first = 1;
    static HMAC_CTX hmacctx;
    unsigned int md_len;
    uint8_t auth[16], hash[EVP_MAX_MD_SIZE];
    
    pthread_mutex_lock(&lock);
    if (first) {
        HMAC_CTX_init(&hmacctx);
        first = 0;
    }

    memcpy(auth, authattr, 16);
    memset(authattr, 0, 16);
    md_len = 0;
    HMAC_Init_ex(&hmacctx, secret, strlen(secret), EVP_md5(), NULL);
    HMAC_Update(&hmacctx, rad, RADLEN(rad));
    HMAC_Final(&hmacctx, hash, &md_len);
    memcpy(authattr, auth, 16);
    if (md_len != 16) {
        debug(DBG_WARN, "message auth computation failed");
        pthread_mutex_unlock(&lock);
        return 0;
    }

    if (memcmp(auth, hash, 16)) {
        debug(DBG_WARN, "message authenticator, wrong value");
        pthread_mutex_unlock(&lock);
        return 0;
    }   
        
    pthread_mutex_unlock(&lock);
    return 1;
}

int createmessageauth(unsigned char *rad, unsigned char *authattrval, char *secret) {
    static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
    static unsigned char first = 1;
    static HMAC_CTX hmacctx;
    unsigned int md_len;

    if (!authattrval)
        return 1;
    
    pthread_mutex_lock(&lock);
    if (first) {
        HMAC_CTX_init(&hmacctx);
        first = 0;
    }

    memset(authattrval, 0, 16);
    md_len = 0;
    HMAC_Init_ex(&hmacctx, secret, strlen(secret), EVP_md5(), NULL);
    HMAC_Update(&hmacctx, rad, RADLEN(rad));
    HMAC_Final(&hmacctx, authattrval, &md_len);
    if (md_len != 16) {
        debug(DBG_WARN, "message auth computation failed");
        pthread_mutex_unlock(&lock);
        return 0;
    }

    pthread_mutex_unlock(&lock);
    return 1;
}

unsigned char *attrget(unsigned char *attrs, int length, uint8_t type) {
    while (length > 1) {
        if (ATTRTYPE(attrs) == type)
            return attrs;
        length -= ATTRLEN(attrs);
        attrs += ATTRLEN(attrs);
    }
    return NULL;
}

void sendrq(struct server *to, struct request *rq) {
    int i;
    uint8_t *attr;

    pthread_mutex_lock(&to->newrq_mutex);
    /* might simplify if only try nextid, might be ok */
    for (i = to->nextid; i < MAX_REQUESTS; i++)
        if (!to->requests[i].buf)
            break;
    if (i == MAX_REQUESTS) {
        for (i = 0; i < to->nextid; i++)
            if (!to->requests[i].buf)
                break;
        if (i == to->nextid) {
            debug(DBG_WARN, "No room in queue, dropping request");
            free(rq->buf);
            pthread_mutex_unlock(&to->newrq_mutex);
            return;
        }
    }
    
    rq->buf[1] = (char)i;

    attr = attrget(rq->buf + 20, RADLEN(rq->buf) - 20, RAD_Attr_Message_Authenticator);
    if (attr && !createmessageauth(rq->buf, ATTRVAL(attr), to->peer.secret)) {
        free(rq->buf);
        pthread_mutex_unlock(&to->newrq_mutex);
        return;
    }

    debug(DBG_DBG, "sendrq: inserting packet with id %d in queue for %s", i, to->peer.host);
    to->requests[i] = *rq;
    to->nextid = i + 1;

    if (!to->newrq) {
        to->newrq = 1;
        debug(DBG_DBG, "signalling client writer");
        pthread_cond_signal(&to->newrq_cond);
    }
    pthread_mutex_unlock(&to->newrq_mutex);
}

void sendreply(struct client *to, unsigned char *buf, struct sockaddr_storage *tosa) {
    struct replyq *replyq = to->replyq;
    
    if (!radsign(buf, (unsigned char *)to->peer.secret)) {
        free(buf);
        debug(DBG_WARN, "sendreply: failed to sign message");
        return;
    }
        
    pthread_mutex_lock(&replyq->count_mutex);
    if (replyq->count == replyq->size) {
        debug(DBG_WARN, "No room in queue, dropping request");
        pthread_mutex_unlock(&replyq->count_mutex);
        free(buf);
        return;
    }

    replyq->replies[replyq->count].buf = buf;
    if (tosa)
        replyq->replies[replyq->count].tosa = *tosa;
    replyq->count++;

    if (replyq->count == 1) {
        debug(DBG_DBG, "signalling server writer");
        pthread_cond_signal(&replyq->count_cond);
    }
    pthread_mutex_unlock(&replyq->count_mutex);
}

int pwdencrypt(uint8_t *in, uint8_t len, char *shared, uint8_t sharedlen, uint8_t *auth) {
    static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
    static unsigned char first = 1;
    static EVP_MD_CTX mdctx;
    unsigned char hash[EVP_MAX_MD_SIZE], *input;
    unsigned int md_len;
    uint8_t i, offset = 0, out[128];
    
    pthread_mutex_lock(&lock);
    if (first) {
        EVP_MD_CTX_init(&mdctx);
        first = 0;
    }

    input = auth;
    for (;;) {
        if (!EVP_DigestInit_ex(&mdctx, EVP_md5(), NULL) ||
            !EVP_DigestUpdate(&mdctx, (uint8_t *)shared, sharedlen) ||
            !EVP_DigestUpdate(&mdctx, input, 16) ||
            !EVP_DigestFinal_ex(&mdctx, hash, &md_len) ||
            md_len != 16) {
            pthread_mutex_unlock(&lock);
            return 0;
        }
        for (i = 0; i < 16; i++)
            out[offset + i] = hash[i] ^ in[offset + i];
        input = out + offset - 16;
        offset += 16;
        if (offset == len)
            break;
    }
    memcpy(in, out, len);
    pthread_mutex_unlock(&lock);
    return 1;
}

int pwddecrypt(uint8_t *in, uint8_t len, char *shared, uint8_t sharedlen, uint8_t *auth) {
    static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
    static unsigned char first = 1;
    static EVP_MD_CTX mdctx;
    unsigned char hash[EVP_MAX_MD_SIZE], *input;
    unsigned int md_len;
    uint8_t i, offset = 0, out[128];
    
    pthread_mutex_lock(&lock);
    if (first) {
        EVP_MD_CTX_init(&mdctx);
        first = 0;
    }

    input = auth;
    for (;;) {
        if (!EVP_DigestInit_ex(&mdctx, EVP_md5(), NULL) ||
            !EVP_DigestUpdate(&mdctx, (uint8_t *)shared, sharedlen) ||
            !EVP_DigestUpdate(&mdctx, input, 16) ||
            !EVP_DigestFinal_ex(&mdctx, hash, &md_len) ||
            md_len != 16) {
            pthread_mutex_unlock(&lock);
            return 0;
        }
        for (i = 0; i < 16; i++)
            out[offset + i] = hash[i] ^ in[offset + i];
        input = in + offset;
        offset += 16;
        if (offset == len)
            break;
    }
    memcpy(in, out, len);
    pthread_mutex_unlock(&lock);
    return 1;
}

int msmppencrypt(uint8_t *text, uint8_t len, uint8_t *shared, uint8_t sharedlen, uint8_t *auth, uint8_t *salt) {
    static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
    static unsigned char first = 1;
    static EVP_MD_CTX mdctx;
    unsigned char hash[EVP_MAX_MD_SIZE];
    unsigned int md_len;
    uint8_t i, offset;
    
    pthread_mutex_lock(&lock);
    if (first) {
        EVP_MD_CTX_init(&mdctx);
        first = 0;
    }

#if 0    
    printf("msppencrypt auth in: ");
    for (i = 0; i < 16; i++)
        printf("%02x ", auth[i]);
    printf("\n");
    
    printf("msppencrypt salt in: ");
    for (i = 0; i < 2; i++)
        printf("%02x ", salt[i]);
    printf("\n");
    
    printf("msppencrypt in: ");
    for (i = 0; i < len; i++)
        printf("%02x ", text[i]);
    printf("\n");
#endif
    
    if (!EVP_DigestInit_ex(&mdctx, EVP_md5(), NULL) ||
        !EVP_DigestUpdate(&mdctx, shared, sharedlen) ||
        !EVP_DigestUpdate(&mdctx, auth, 16) ||
        !EVP_DigestUpdate(&mdctx, salt, 2) ||
        !EVP_DigestFinal_ex(&mdctx, hash, &md_len)) {
        pthread_mutex_unlock(&lock);
        return 0;
    }

#if 0    
    printf("msppencrypt hash: ");
    for (i = 0; i < 16; i++)
        printf("%02x ", hash[i]);
    printf("\n");
#endif
    
    for (i = 0; i < 16; i++)
        text[i] ^= hash[i];
    
    for (offset = 16; offset < len; offset += 16) {
#if 0   
        printf("text + offset - 16 c(%d): ", offset / 16);
        for (i = 0; i < 16; i++)
            printf("%02x ", (text + offset - 16)[i]);
        printf("\n");
#endif
        if (!EVP_DigestInit_ex(&mdctx, EVP_md5(), NULL) ||
            !EVP_DigestUpdate(&mdctx, shared, sharedlen) ||
            !EVP_DigestUpdate(&mdctx, text + offset - 16, 16) ||
            !EVP_DigestFinal_ex(&mdctx, hash, &md_len) ||
            md_len != 16) {
            pthread_mutex_unlock(&lock);
            return 0;
        }
#if 0   
        printf("msppencrypt hash: ");
        for (i = 0; i < 16; i++)
            printf("%02x ", hash[i]);
        printf("\n");
#endif    
        
        for (i = 0; i < 16; i++)
            text[offset + i] ^= hash[i];
    }
    
#if 0
    printf("msppencrypt out: ");
    for (i = 0; i < len; i++)
        printf("%02x ", text[i]);
    printf("\n");
#endif

    pthread_mutex_unlock(&lock);
    return 1;
}

int msmppdecrypt(uint8_t *text, uint8_t len, uint8_t *shared, uint8_t sharedlen, uint8_t *auth, uint8_t *salt) {
    static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
    static unsigned char first = 1;
    static EVP_MD_CTX mdctx;
    unsigned char hash[EVP_MAX_MD_SIZE];
    unsigned int md_len;
    uint8_t i, offset;
    char plain[255];
    
    pthread_mutex_lock(&lock);
    if (first) {
        EVP_MD_CTX_init(&mdctx);
        first = 0;
    }

#if 0    
    printf("msppdecrypt auth in: ");
    for (i = 0; i < 16; i++)
        printf("%02x ", auth[i]);
    printf("\n");
    
    printf("msppedecrypt salt in: ");
    for (i = 0; i < 2; i++)
        printf("%02x ", salt[i]);
    printf("\n");
    
    printf("msppedecrypt in: ");
    for (i = 0; i < len; i++)
        printf("%02x ", text[i]);
    printf("\n");
#endif
    
    if (!EVP_DigestInit_ex(&mdctx, EVP_md5(), NULL) ||
        !EVP_DigestUpdate(&mdctx, shared, sharedlen) ||
        !EVP_DigestUpdate(&mdctx, auth, 16) ||
        !EVP_DigestUpdate(&mdctx, salt, 2) ||
        !EVP_DigestFinal_ex(&mdctx, hash, &md_len)) {
        pthread_mutex_unlock(&lock);
        return 0;
    }

#if 0    
    printf("msppedecrypt hash: ");
    for (i = 0; i < 16; i++)
        printf("%02x ", hash[i]);
    printf("\n");
#endif
    
    for (i = 0; i < 16; i++)
        plain[i] = text[i] ^ hash[i];
    
    for (offset = 16; offset < len; offset += 16) {
#if 0   
        printf("text + offset - 16 c(%d): ", offset / 16);
        for (i = 0; i < 16; i++)
            printf("%02x ", (text + offset - 16)[i]);
        printf("\n");
#endif
        if (!EVP_DigestInit_ex(&mdctx, EVP_md5(), NULL) ||
            !EVP_DigestUpdate(&mdctx, shared, sharedlen) ||
            !EVP_DigestUpdate(&mdctx, text + offset - 16, 16) ||
            !EVP_DigestFinal_ex(&mdctx, hash, &md_len) ||
            md_len != 16) {
            pthread_mutex_unlock(&lock);
            return 0;
        }
#if 0   
    printf("msppedecrypt hash: ");
    for (i = 0; i < 16; i++)
        printf("%02x ", hash[i]);
    printf("\n");
#endif    

    for (i = 0; i < 16; i++)
        plain[offset + i] = text[offset + i] ^ hash[i];
    }

    memcpy(text, plain, len);
#if 0
    printf("msppedecrypt out: ");
    for (i = 0; i < len; i++)
        printf("%02x ", text[i]);
    printf("\n");
#endif

    pthread_mutex_unlock(&lock);
    return 1;
}

struct realm *id2realm(char *id, uint8_t len) {
    int i;
    for (i = 0; i < realm_count; i++)
        if (!regexec(&realms[i].regex, id, 0, NULL, 0)) {
            debug(DBG_DBG, "found matching realm: %s", realms[i].name);
            return realms + i;
        }
    return NULL;
}

int rqinqueue(struct server *to, struct client *from, uint8_t id) {
    int i;
    
    pthread_mutex_lock(&to->newrq_mutex);
    for (i = 0; i < MAX_REQUESTS; i++)
        if (to->requests[i].buf && to->requests[i].origid == id && to->requests[i].from == from)
            break;
    pthread_mutex_unlock(&to->newrq_mutex);
    
    return i < MAX_REQUESTS;
}

int attrvalidate(unsigned char *attrs, int length) {
    while (length > 1) {
        if (ATTRLEN(attrs) < 2) {
            debug(DBG_WARN, "attrvalidate: invalid attribute length %d", ATTRLEN(attrs));
            return 0;
        }
        length -= ATTRLEN(attrs);
        if (length < 0) {
            debug(DBG_WARN, "attrvalidate: attribute length %d exceeds packet length", ATTRLEN(attrs));
            return 0;
        }
        attrs += ATTRLEN(attrs);
    }
    if (length)
        debug(DBG_WARN, "attrvalidate: malformed packet? remaining byte after last attribute");
    return 1;
}

int pwdrecrypt(uint8_t *pwd, uint8_t len, char *oldsecret, char *newsecret, uint8_t *oldauth, uint8_t *newauth) {
#ifdef DEBUG    
    int i;
#endif    
    if (len < 16 || len > 128 || len % 16) {
        debug(DBG_WARN, "pwdrecrypt: invalid password length");
        return 0;
    }
        
    if (!pwddecrypt(pwd, len, oldsecret, strlen(oldsecret), oldauth)) {
        debug(DBG_WARN, "pwdrecrypt: cannot decrypt password");
        return 0;
    }
#ifdef DEBUG
    printf("pwdrecrypt: password: ");
    for (i = 0; i < len; i++)
        printf("%02x ", pwd[i]);
    printf("\n");
#endif  
    if (!pwdencrypt(pwd, len, newsecret, strlen(newsecret), newauth)) {
        debug(DBG_WARN, "pwdrecrypt: cannot encrypt password");
        return 0;
    }
    return 1;
}

int msmpprecrypt(uint8_t *msmpp, uint8_t len, char *oldsecret, char *newsecret, unsigned char *oldauth, char *newauth) {
    if (len < 18)
        return 0;
    if (!msmppdecrypt(msmpp + 2, len - 2, (unsigned char *)oldsecret, strlen(oldsecret), oldauth, msmpp)) {
        debug(DBG_WARN, "msmpprecrypt: failed to decrypt msppe key");
        return 0;
    }
    if (!msmppencrypt(msmpp + 2, len - 2, (unsigned char *)newsecret, strlen(newsecret), (unsigned char *)newauth, msmpp)) {
        debug(DBG_WARN, "msmpprecrypt: failed to encrypt msppe key");
        return 0;
    }
    return 1;
}

int msmppe(unsigned char *attrs, int length, uint8_t type, char *attrtxt, struct request *rq,
           char *oldsecret, char *newsecret) {
    unsigned char *attr;
    
    for (attr = attrs; (attr = attrget(attr, length - (attr - attrs), type)); attr += ATTRLEN(attr)) {
        debug(DBG_DBG, "msmppe: Got %s", attrtxt);
        if (!msmpprecrypt(ATTRVAL(attr), ATTRVALLEN(attr), oldsecret, newsecret, rq->buf + 4, rq->origauth))
            return 0;
    }
    return 1;
}

void respondstatusserver(struct request *rq) {
    unsigned char *resp;

    resp = malloc(20);
    if (!resp) {
        debug(DBG_ERR, "respondstatusserver: malloc failed");
        return;
    }
    memcpy(resp, rq->buf, 20);
    resp[0] = RAD_Access_Accept;
    resp[2] = 0;
    resp[3] = 20;
    debug(DBG_DBG, "respondstatusserver: responding to %s", rq->from->peer.host);
    sendreply(rq->from, resp, rq->from->peer.type == 'U' ? &rq->fromsa : NULL);
}

void respondreject(struct request *rq, char *message) {
    unsigned char *resp;
    int len = 20;

    if (message)
        len += 2 + strlen(message);
    
    resp = malloc(len);
    if (!resp) {
        debug(DBG_ERR, "respondreject: malloc failed");
        return;
    }
    memcpy(resp, rq->buf, 20);
    resp[0] = RAD_Access_Reject;
    *(uint16_t *)(resp + 2) = htons(len);
    if (message) {
        resp[20] = RAD_Attr_Reply_Message;
        resp[21] = len - 20;
        memcpy(resp + 22, message, len - 22);
    }
    sendreply(rq->from, resp, rq->from->peer.type == 'U' ? &rq->fromsa : NULL);
}

void radsrv(struct request *rq) {
    uint8_t code, id, *auth, *attrs, *attr;
    uint16_t len;
    struct server *to = NULL;
    char username[256];
    unsigned char *buf, newauth[16];
    struct realm *realm = NULL;
    
    buf = rq->buf;
    code = *(uint8_t *)buf;
    id = *(uint8_t *)(buf + 1);
    len = RADLEN(buf);
    auth = (uint8_t *)(buf + 4);

    debug(DBG_DBG, "radsrv: code %d, id %d, length %d", code, id, len);
    
    if (code != RAD_Access_Request && code != RAD_Status_Server) {
        debug(DBG_INFO, "radsrv: server currently accepts only access-requests and status-server, ignoring");
        free(buf);
        return;
    }

    len -= 20;
    attrs = buf + 20;

    if (!attrvalidate(attrs, len)) {
        debug(DBG_WARN, "radsrv: attribute validation failed, ignoring packet");
        free(buf);
        return;
    }

    if (code == RAD_Access_Request) {
        attr = attrget(attrs, len, RAD_Attr_User_Name);
        if (!attr) {
            debug(DBG_WARN, "radsrv: ignoring request, no username attribute");
            free(buf);
            return;
        }
        memcpy(username, ATTRVAL(attr), ATTRVALLEN(attr));
        username[ATTRVALLEN(attr)] = '\0';
        debug(DBG_DBG, "Access Request with username: %s", username);

        realm = id2realm(username, strlen(username));
        if (!realm) {
            debug(DBG_INFO, "radsrv: ignoring request, don't know where to send it");
            free(buf);
            return;
        }
        to = realm->server;

        if (to && rqinqueue(to, rq->from, id)) {
            debug(DBG_INFO, "radsrv: already got request from host %s with id %d, ignoring", rq->from->peer.host, id);
            free(buf);
            return;
        }
    }
    
    attr = attrget(attrs, len, RAD_Attr_Message_Authenticator);
    if (attr && (ATTRVALLEN(attr) != 16 || !checkmessageauth(buf, ATTRVAL(attr), rq->from->peer.secret))) {
        debug(DBG_WARN, "radsrv: message authentication failed");
        free(buf);
        return;
    }
    
    if (code == RAD_Status_Server) {
        respondstatusserver(rq);
        return;
    }

    if (!to) {
        debug(DBG_INFO, "radsrv: sending reject to %s for %s", rq->from->peer.host, username);
        respondreject(rq, realm->message);
        return;
    }
    
    if (!RAND_bytes(newauth, 16)) {
        debug(DBG_WARN, "radsrv: failed to generate random auth");
        free(buf);
        return;
    }

#ifdef DEBUG    
    printauth("auth", auth);
#endif

    attr = attrget(attrs, len, RAD_Attr_User_Password);
    if (attr) {
        debug(DBG_DBG, "radsrv: found userpwdattr with value length %d", ATTRVALLEN(attr));
        if (!pwdrecrypt(ATTRVAL(attr), ATTRVALLEN(attr), rq->from->peer.secret, to->peer.secret, auth, newauth)) {
            free(buf);
            return;
        }
    }
    
    attr = attrget(attrs, len, RAD_Attr_Tunnel_Password);
    if (attr) {
        debug(DBG_DBG, "radsrv: found tunnelpwdattr with value length %d", ATTRVALLEN(attr));
        if (!pwdrecrypt(ATTRVAL(attr), ATTRVALLEN(attr), rq->from->peer.secret, to->peer.secret, auth, newauth)) {
            free(buf);
            return;
        }
    }

    rq->origid = id;
    memcpy(rq->origauth, auth, 16);
    memcpy(auth, newauth, 16);
    sendrq(to, rq);
}

void *clientrd(void *arg) {
    struct server *server = (struct server *)arg;
    struct client *from;
    int i, len, sublen;
    unsigned char *buf, *messageauth, *subattrs, *attrs, *attr;
    struct sockaddr_storage fromsa;
    struct timeval lastconnecttry;
    char tmp[256];
    
    for (;;) {
        lastconnecttry = server->lastconnecttry;
        buf = (server->peer.type == 'U' ? radudpget(server->sock, NULL, &server, NULL) : radtlsget(server->peer.ssl));
        if (!buf && server->peer.type == 'T') {
            tlsconnect(server, &lastconnecttry, "clientrd");
            continue;
        }
    
        server->connectionok = 1;

        i = buf[1]; /* i is the id */

        switch (*buf) {
        case RAD_Access_Accept:
            debug(DBG_DBG, "got Access Accept with id %d", i);
            break;
        case RAD_Access_Reject:
            debug(DBG_DBG, "got Access Reject with id %d", i);
            break;
        case RAD_Access_Challenge:
            debug(DBG_DBG, "got Access Challenge with id %d", i);
            break;
        default:
            free(buf);
            debug(DBG_INFO, "clientrd: discarding, only accept access accept, access reject and access challenge messages");
            continue;
        }
        
        pthread_mutex_lock(&server->newrq_mutex);
        if (!server->requests[i].buf || !server->requests[i].tries) {
            pthread_mutex_unlock(&server->newrq_mutex);
            free(buf);
            debug(DBG_INFO, "clientrd: no matching request sent with this id, ignoring");
            continue;
        }

        if (server->requests[i].received) {
            pthread_mutex_unlock(&server->newrq_mutex);
            free(buf);
            debug(DBG_INFO, "clientrd: already received, ignoring");
            continue;
        }
        
        if (!validauth(buf, server->requests[i].buf + 4, (unsigned char *)server->peer.secret)) {
            pthread_mutex_unlock(&server->newrq_mutex);
            free(buf);
            debug(DBG_WARN, "clientrd: invalid auth, ignoring");
            continue;
        }
        
        from = server->requests[i].from;
        len = RADLEN(buf) - 20;
        attrs = buf + 20;

        if (!attrvalidate(attrs, len)) {
            pthread_mutex_unlock(&server->newrq_mutex);
            free(buf);
            debug(DBG_WARN, "clientrd: attribute validation failed, ignoring packet");
            continue;
        }
        
        /* Message Authenticator */
        messageauth = attrget(attrs, len, RAD_Attr_Message_Authenticator);
        if (messageauth) {
            if (ATTRVALLEN(messageauth) != 16) {
                pthread_mutex_unlock(&server->newrq_mutex);
                free(buf);
                debug(DBG_WARN, "clientrd: illegal message auth attribute length, ignoring packet");
                continue;
            }
            memcpy(tmp, buf + 4, 16);
            memcpy(buf + 4, server->requests[i].buf + 4, 16);
            if (!checkmessageauth(buf, ATTRVAL(messageauth), server->peer.secret)) {
                pthread_mutex_unlock(&server->newrq_mutex);
                free(buf);
                debug(DBG_WARN, "clientrd: message authentication failed");
                continue;
            }
            memcpy(buf + 4, tmp, 16);
            debug(DBG_DBG, "clientrd: message auth ok");
        }
        
        if (*server->requests[i].buf == RAD_Status_Server) {
            server->requests[i].received = 1;
            pthread_mutex_unlock(&server->newrq_mutex);
            free(buf);
            debug(DBG_INFO, "clientrd: got status server response from %s", server->peer.host);
            continue;
        }

        /* MS MPPE */
        for (attr = attrs; (attr = attrget(attr, len - (attr - attrs), RAD_Attr_Vendor_Specific)); attr += ATTRLEN(attr)) {
            if (ATTRVALLEN(attr) <= 4)
                break;
            
            if (((uint16_t *)attr)[1] != 0 || ntohs(((uint16_t *)attr)[2]) != 311) /* 311 == MS */
                continue;
            
            sublen = ATTRVALLEN(attr) - 4;
            subattrs = ATTRVAL(attr) + 4;  
            if (!attrvalidate(subattrs, sublen) ||
                !msmppe(subattrs, sublen, RAD_VS_ATTR_MS_MPPE_Send_Key, "MS MPPE Send Key",
                        server->requests + i, server->peer.secret, from->peer.secret) ||
                !msmppe(subattrs, sublen, RAD_VS_ATTR_MS_MPPE_Recv_Key, "MS MPPE Recv Key",
                        server->requests + i, server->peer.secret, from->peer.secret))
                break;
        }
        if (attr) {
            pthread_mutex_unlock(&server->newrq_mutex);
            free(buf);
            debug(DBG_WARN, "clientrd: MS attribute handling failed, ignoring packet");
            continue;
        }
        
        if (*buf == RAD_Access_Accept || *buf == RAD_Access_Reject) {
            attr = attrget(server->requests[i].buf + 20, RADLEN(server->requests[i].buf) - 20, RAD_Attr_User_Name);
            /* we know the attribute exists */
            memcpy(tmp, ATTRVAL(attr), ATTRVALLEN(attr));
            tmp[ATTRVALLEN(attr)] = '\0';
            switch (*buf) {
            case RAD_Access_Accept:
                debug(DBG_INFO, "Access Accept for %s from %s", tmp, server->peer.host);
                break;
            case RAD_Access_Reject:
                debug(DBG_INFO, "Access Reject for %s from %s", tmp, server->peer.host);
                break;
            }
        }
        
        /* once we set received = 1, requests[i] may be reused */
        buf[1] = (char)server->requests[i].origid;
        memcpy(buf + 4, server->requests[i].origauth, 16);
#ifdef DEBUG    
        printauth("origauth/buf+4", buf + 4);
#endif
        
        if (messageauth) {
            if (!createmessageauth(buf, ATTRVAL(messageauth), from->peer.secret)) {
                pthread_mutex_unlock(&server->newrq_mutex);
                free(buf);
                continue;
            }
            debug(DBG_DBG, "clientrd: computed messageauthattr");
        }

        if (from->peer.type == 'U')
            fromsa = server->requests[i].fromsa;
        server->requests[i].received = 1;
        pthread_mutex_unlock(&server->newrq_mutex);

        debug(DBG_DBG, "clientrd: giving packet back to where it came from");
        sendreply(from, buf, from->peer.type == 'U' ? &fromsa : NULL);
    }
}

void *clientwr(void *arg) {
    struct server *server = (struct server *)arg;
    struct request *rq;
    pthread_t clientrdth;
    int i;
    uint8_t rnd;
    struct timeval now, lastsend;
    struct timespec timeout;
    struct request statsrvrq;
    unsigned char statsrvbuf[38];

    memset(&timeout, 0, sizeof(struct timespec));
    
    if (server->statusserver) {
        memset(&statsrvrq, 0, sizeof(struct request));
        memset(statsrvbuf, 0, sizeof(statsrvbuf));
        statsrvbuf[0] = RAD_Status_Server;
        statsrvbuf[3] = 38;
        statsrvbuf[20] = RAD_Attr_Message_Authenticator;
        statsrvbuf[21] = 18;
        gettimeofday(&lastsend, NULL);
    }
    
    if (server->peer.type == 'U') {
        if ((server->sock = connecttoserver(server->peer.addrinfo)) < 0)
            debugx(1, DBG_ERR, "clientwr: connecttoserver failed");
    } else
        tlsconnect(server, NULL, "new client");
    
    if (pthread_create(&clientrdth, NULL, clientrd, (void *)server))
        debugx(1, DBG_ERR, "clientwr: pthread_create failed");

    for (;;) {
        pthread_mutex_lock(&server->newrq_mutex);
        if (!server->newrq) {
            gettimeofday(&now, NULL);
            if (server->statusserver) {
                /* random 0-7 seconds */
                RAND_bytes(&rnd, 1);
                rnd /= 32;
                if (!timeout.tv_sec || timeout.tv_sec - now.tv_sec > lastsend.tv_sec + STATUS_SERVER_PERIOD + rnd)
                    timeout.tv_sec = lastsend.tv_sec + STATUS_SERVER_PERIOD + rnd;
            }   
            if (timeout.tv_sec) {
                debug(DBG_DBG, "clientwr: waiting up to %ld secs for new request", timeout.tv_sec - now.tv_sec);
                pthread_cond_timedwait(&server->newrq_cond, &server->newrq_mutex, &timeout);
                timeout.tv_sec = 0;
            } else {
                debug(DBG_DBG, "clientwr: waiting for new request");
                pthread_cond_wait(&server->newrq_cond, &server->newrq_mutex);
            }
        }
        if (server->newrq) {
            debug(DBG_DBG, "clientwr: got new request");
            server->newrq = 0;
        } else
            debug(DBG_DBG, "clientwr: request timer expired, processing request queue");
        pthread_mutex_unlock(&server->newrq_mutex);

        for (i = 0; i < MAX_REQUESTS; i++) {
            pthread_mutex_lock(&server->newrq_mutex);
            while (!server->requests[i].buf && i < MAX_REQUESTS)
                i++;
            if (i == MAX_REQUESTS) {
                pthread_mutex_unlock(&server->newrq_mutex);
                break;
            }
            rq = server->requests + i;

            if (rq->received) {
                debug(DBG_DBG, "clientwr: packet %d in queue is marked as received", i);
                if (rq->buf) {
                    debug(DBG_DBG, "clientwr: freeing received packet %d from queue", i);
                    free(rq->buf);
                    /* setting this to NULL means that it can be reused */
                    rq->buf = NULL;
                }
                pthread_mutex_unlock(&server->newrq_mutex);
                continue;
            }
            
            gettimeofday(&now, NULL);
            if (now.tv_sec < rq->expiry.tv_sec) {
                if (!timeout.tv_sec || rq->expiry.tv_sec < timeout.tv_sec)
                    timeout.tv_sec = rq->expiry.tv_sec;
                pthread_mutex_unlock(&server->newrq_mutex);
                continue;
            }

            if (rq->tries == (*rq->buf == RAD_Status_Server || server->peer.type == 'T'
                              ? 1 : REQUEST_RETRIES)) {
                debug(DBG_DBG, "clientwr: removing expired packet from queue");
                if (*rq->buf == RAD_Status_Server)
                    debug(DBG_WARN, "clientwr: no status server response, %s dead?", server->peer.host);
                free(rq->buf);
                /* setting this to NULL means that it can be reused */
                rq->buf = NULL;
                pthread_mutex_unlock(&server->newrq_mutex);
                continue;
            }
            pthread_mutex_unlock(&server->newrq_mutex);

            rq->expiry.tv_sec = now.tv_sec +
                (*rq->buf == RAD_Status_Server || server->peer.type == 'T'
                 ? REQUEST_EXPIRY : REQUEST_EXPIRY / REQUEST_RETRIES);
            if (!timeout.tv_sec || rq->expiry.tv_sec < timeout.tv_sec)
                timeout.tv_sec = rq->expiry.tv_sec;
            rq->tries++;
            clientradput(server, server->requests[i].buf);
            gettimeofday(&lastsend, NULL);
        }
        if (server->statusserver) {
            gettimeofday(&now, NULL);
            if (now.tv_sec - lastsend.tv_sec >= STATUS_SERVER_PERIOD) {
                if (!RAND_bytes(statsrvbuf + 4, 16)) {
                    debug(DBG_WARN, "clientwr: failed to generate random auth");
                    continue;
                }
                statsrvrq.buf = malloc(sizeof(statsrvbuf));
                if (!statsrvrq.buf) {
                    debug(DBG_ERR, "clientwr: malloc failed");
                    continue;
                }
                memcpy(statsrvrq.buf, statsrvbuf, sizeof(statsrvbuf));
                debug(DBG_DBG, "clientwr: sending status server to %s", server->peer.host);
                lastsend.tv_sec = now.tv_sec;
                sendrq(server, &statsrvrq);
            }
        }
    }
}

void *udpserverwr(void *arg) {
    struct replyq *replyq = &udp_server_replyq;
    struct reply *reply = replyq->replies;
    
    pthread_mutex_lock(&replyq->count_mutex);
    for (;;) {
        while (!replyq->count) {
            debug(DBG_DBG, "udp server writer, waiting for signal");
            pthread_cond_wait(&replyq->count_cond, &replyq->count_mutex);
            debug(DBG_DBG, "udp server writer, got signal");
        }
        pthread_mutex_unlock(&replyq->count_mutex);
        
        if (sendto(udp_server_sock, reply->buf, RADLEN(reply->buf), 0,
                   (struct sockaddr *)&reply->tosa, SOCKADDR_SIZE(reply->tosa)) < 0)
            debug(DBG_WARN, "sendudp: send failed");
        free(reply->buf);
        
        pthread_mutex_lock(&replyq->count_mutex);
        replyq->count--;
        memmove(replyq->replies, replyq->replies + 1,
                replyq->count * sizeof(struct reply));
    }
}

void *udpserverrd(void *arg) {
    struct request rq;
    pthread_t udpserverwrth;

    if ((udp_server_sock = bindtoaddr(udp_server_listen->addrinfo)) < 0)
        debugx(1, DBG_ERR, "udpserverrd: socket/bind failed");

    debug(DBG_WARN, "udpserverrd: listening for UDP on %s:%s",
          udp_server_listen->host ? udp_server_listen->host : "*", udp_server_listen->port);

    if (pthread_create(&udpserverwrth, NULL, udpserverwr, NULL))
        debugx(1, DBG_ERR, "pthread_create failed");
    
    for (;;) {
        memset(&rq, 0, sizeof(struct request));
        rq.buf = radudpget(udp_server_sock, &rq.from, NULL, &rq.fromsa);
        radsrv(&rq);
    }
}

void *tlsserverwr(void *arg) {
    int cnt;
    unsigned long error;
    struct client *client = (struct client *)arg;
    struct replyq *replyq;
    
    debug(DBG_DBG, "tlsserverwr starting for %s", client->peer.host);
    replyq = client->replyq;
    pthread_mutex_lock(&replyq->count_mutex);
    for (;;) {
        while (!replyq->count) {
            if (client->peer.ssl) {         
                debug(DBG_DBG, "tls server writer, waiting for signal");
                pthread_cond_wait(&replyq->count_cond, &replyq->count_mutex);
                debug(DBG_DBG, "tls server writer, got signal");
            }
            if (!client->peer.ssl) {
                /* ssl might have changed while waiting */
                pthread_mutex_unlock(&replyq->count_mutex);
                debug(DBG_DBG, "tlsserverwr: exiting as requested");
                pthread_exit(NULL);
            }
        }
        pthread_mutex_unlock(&replyq->count_mutex);
        cnt = SSL_write(client->peer.ssl, replyq->replies->buf, RADLEN(replyq->replies->buf));
        if (cnt > 0)
            debug(DBG_DBG, "tlsserverwr: Sent %d bytes, Radius packet of length %d",
                  cnt, RADLEN(replyq->replies->buf));
        else
            while ((error = ERR_get_error()))
                debug(DBG_ERR, "tlsserverwr: SSL: %s", ERR_error_string(error, NULL));
        free(replyq->replies->buf);

        pthread_mutex_lock(&replyq->count_mutex);
        replyq->count--;
        memmove(replyq->replies, replyq->replies + 1, replyq->count * sizeof(struct reply));
    }
}

void *tlsserverrd(void *arg) {
    struct request rq;
    unsigned long error;
    int s;
    struct client *client = (struct client *)arg;
    pthread_t tlsserverwrth;
    SSL *ssl;
    
    debug(DBG_DBG, "tlsserverrd starting for %s", client->peer.host);
    ssl = client->peer.ssl;

    if (SSL_accept(ssl) <= 0) {
        while ((error = ERR_get_error()))
            debug(DBG_ERR, "tlsserverrd: SSL: %s", ERR_error_string(error, NULL));
        debug(DBG_ERR, "SSL_accept failed");
        goto errexit;
    }
    if (tlsverifycert(&client->peer)) {
        if (pthread_create(&tlsserverwrth, NULL, tlsserverwr, (void *)client)) {
            debug(DBG_ERR, "tlsserverrd: pthread_create failed");
            goto errexit;
        }
        for (;;) {
            memset(&rq, 0, sizeof(struct request));
            rq.buf = radtlsget(client->peer.ssl);
            if (!rq.buf)
                break;
            debug(DBG_DBG, "tlsserverrd: got Radius message from %s", client->peer.host);
            rq.from = client;
            radsrv(&rq);
        }
        debug(DBG_ERR, "tlsserverrd: connection lost");
        /* stop writer by setting peer.ssl to NULL and give signal in case waiting for data */
        client->peer.ssl = NULL;
        pthread_mutex_lock(&client->replyq->count_mutex);
        pthread_cond_signal(&client->replyq->count_cond);
        pthread_mutex_unlock(&client->replyq->count_mutex);
        debug(DBG_DBG, "tlsserverrd: waiting for writer to end");
        pthread_join(tlsserverwrth, NULL);
    }
    
 errexit:
    s = SSL_get_fd(ssl);
    SSL_free(ssl);
    shutdown(s, SHUT_RDWR);
    close(s);
    debug(DBG_DBG, "tlsserverrd thread for %s exiting", client->peer.host);
    client->peer.ssl = NULL;
    pthread_exit(NULL);
}

int tlslistener() {
    pthread_t tlsserverth;
    int s, snew;
    struct sockaddr_storage from;
    size_t fromlen = sizeof(from);
    struct client *client;

    if ((s = bindtoaddr(tcp_server_listen->addrinfo)) < 0)
        debugx(1, DBG_ERR, "tlslistener: socket/bind failed");
    
    listen(s, 0);
    debug(DBG_WARN, "listening for incoming TCP on %s:%s",
          tcp_server_listen->host ? tcp_server_listen->host : "*", tcp_server_listen->port);

    for (;;) {
        snew = accept(s, (struct sockaddr *)&from, &fromlen);
        if (snew < 0) {
            debug(DBG_WARN, "accept failed");
            continue;
        }
        debug(DBG_WARN, "incoming TLS connection from %s", addr2string((struct sockaddr *)&from, fromlen));

        client = find_client('T', (struct sockaddr *)&from, NULL);
        if (!client) {
            debug(DBG_WARN, "ignoring request, not a known TLS client");
            shutdown(snew, SHUT_RDWR);
            close(snew);
            continue;
        }

        if (client->peer.ssl) {
            debug(DBG_WARN, "Ignoring incoming TLS connection, already have one from this client");
            shutdown(snew, SHUT_RDWR);
            close(snew);
            continue;
        }
        client->peer.ssl = SSL_new(client->peer.ssl_ctx);
        SSL_set_fd(client->peer.ssl, snew);
        if (pthread_create(&tlsserverth, NULL, tlsserverrd, (void *)client)) {
            debug(DBG_ERR, "tlslistener: pthread_create failed");
            SSL_free(client->peer.ssl);
            shutdown(snew, SHUT_RDWR);
            close(snew);
            client->peer.ssl = NULL;
            continue;
        }
        pthread_detach(tlsserverth);
    }
    return 0;
}

void tlsadd(char *value, char *cacertfile, char *cacertpath, char *certfile, char *certkeyfile, char *certkeypwd) {
    struct tls *new;
    SSL_CTX *ctx;
    int i;
    unsigned long error;
    
    if (!certfile || !certkeyfile)
        debugx(1, DBG_ERR, "TLSCertificateFile and TLSCertificateKeyFile must be specified in TLS context %s", value);

    if (!cacertfile && !cacertpath)
        debugx(1, DBG_ERR, "CA Certificate file or path need to be specified in TLS context %s", value);

    if (!ssl_locks) {
        ssl_locks = malloc(CRYPTO_num_locks() * sizeof(pthread_mutex_t));
        ssl_lock_count = OPENSSL_malloc(CRYPTO_num_locks() * sizeof(long));
        for (i = 0; i < CRYPTO_num_locks(); i++) {
            ssl_lock_count[i] = 0;
            pthread_mutex_init(&ssl_locks[i], NULL);
        }
        CRYPTO_set_id_callback(ssl_thread_id);
        CRYPTO_set_locking_callback(ssl_locking_callback);

        SSL_load_error_strings();
        SSL_library_init();

        while (!RAND_status()) {
            time_t t = time(NULL);
            pid_t pid = getpid();
            RAND_seed((unsigned char *)&t, sizeof(time_t));
            RAND_seed((unsigned char *)&pid, sizeof(pid));
        }
    }
    ctx = SSL_CTX_new(TLSv1_method());
    if (certkeypwd) {
        SSL_CTX_set_default_passwd_cb_userdata(ctx, certkeypwd);
        SSL_CTX_set_default_passwd_cb(ctx, pem_passwd_cb);
    }
    if (!SSL_CTX_use_certificate_chain_file(ctx, certfile) ||
        !SSL_CTX_use_PrivateKey_file(ctx, certkeyfile, SSL_FILETYPE_PEM) ||
        !SSL_CTX_check_private_key(ctx) ||
        !SSL_CTX_load_verify_locations(ctx, cacertfile, cacertpath)) {
        while ((error = ERR_get_error()))
            debug(DBG_ERR, "SSL: %s", ERR_error_string(error, NULL));
        debugx(1, DBG_ERR, "Error initialising SSL/TLS in TLS context %s", value);
    }
    
    SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER | SSL_VERIFY_FAIL_IF_NO_PEER_CERT, verify_cb);
    SSL_CTX_set_verify_depth(ctx, MAX_CERT_DEPTH + 1);
    
    tls_count++;
    tls = realloc(tls, tls_count * sizeof(struct tls));
    if (!tls)
        debugx(1, DBG_ERR, "malloc failed");
    new = tls + tls_count - 1;
    memset(new, 0, sizeof(struct tls));
    new->name = stringcopy(value, 0);
    if (!new->name)
        debugx(1, DBG_ERR, "malloc failed");
    new->ctx = ctx;
    new->count = 0;
    debug(DBG_DBG, "tlsadd: added TLS context %s", value);
}

void tlsfree() {
    int i;
    for (i = 0; i < tls_count; i++)
        if (!tls[i].count)
            SSL_CTX_free(tls[i].ctx);
    tls_count = 0;
    free(tls);
    tls = NULL;
}

SSL_CTX *tlsgetctx(char *alt1, char *alt2) {
    int i, c1 = -1, c2 = -1;
    for (i = 0; i < tls_count; i++) {
        if (!strcasecmp(tls[i].name, alt1)) {
            c1 = i;
            break;
        }
        if (c2 == -1 && alt2 && !strcasecmp(tls[i].name, alt2))
            c2 = i;
    }

    i = (c1 == -1 ? c2 : c1);
    if (i == -1)
        return NULL;
    tls[i].count++;
    return tls[i].ctx;
}

void addrealm(char *value, char *server, char *message) {
    int i, n;
    struct realm *realm;
    char *s, *regex = NULL;

    if (server) {
        for (i = 0; i < server_count; i++)
            if (!strcasecmp(server, servers[i].peer.host))
                break;
        if (i == server_count)
            debugx(1, DBG_ERR, "addrealm failed, no server %s", server);
    }
    
    if (*value == '/') {
        /* regexp, remove optional trailing / if present */
        if (value[strlen(value) - 1] == '/')
            value[strlen(value) - 1] = '\0';
    } else {
        /* not a regexp, let us make it one */
        if (*value == '*' && !value[1])
            regex = stringcopy(".*", 0);
        else {
            for (n = 0, s = value; *s;)
                if (*s++ == '.')
                    n++;
            regex = malloc(strlen(value) + n + 3);
            if (regex) {
                regex[0] = '@';
                for (n = 1, s = value; *s; s++) {
                    if (*s == '.')
                        regex[n++] = '\\';
                    regex[n++] = *s;
                }
                regex[n++] = '$';
                regex[n] = '\0';
            }
        }
        if (!regex)
            debugx(1, DBG_ERR, "malloc failed");
        debug(DBG_DBG, "addrealm: constructed regexp %s from %s", regex, value);
    }

    realm_count++;
    realms = realloc(realms, realm_count * sizeof(struct realm));
    if (!realms)
        debugx(1, DBG_ERR, "malloc failed");
    realm = realms + realm_count - 1;
    memset(realm, 0, sizeof(struct realm));
    realm->name = stringcopy(value, 0);
    if (!realm->name)
        debugx(1, DBG_ERR, "malloc failed");
    if (message && strlen(message) > 253)
        debugx(1, DBG_ERR, "ReplyMessage can be at most 253 bytes");
    realm->message = message;
    if (server)
        realm->server = servers + i;
    if (regcomp(&realm->regex, regex ? regex : value + 1, REG_ICASE | REG_NOSUB))
        debugx(1, DBG_ERR, "addrealm: failed to compile regular expression %s", regex ? regex : value + 1);
    if (regex)
        free(regex);
    debug(DBG_DBG, "addrealm: added realm %s for server %s", value, server);
}

char *parsehostport(char *s, struct peer *peer) {
    char *p, *field;
    int ipv6 = 0;

    p = s;
    /* allow literal addresses and port, e.g. [2001:db8::1]:1812 */
    if (*p == '[') {
        p++;
        field = p;
        for (; *p && *p != ']' && *p != ' ' && *p != '\t' && *p != '\n'; p++);
        if (*p != ']')
            debugx(1, DBG_ERR, "no ] matching initial [");
        ipv6 = 1;
    } else {
        field = p;
        for (; *p && *p != ':' && *p != ' ' && *p != '\t' && *p != '\n'; p++);
    }
    if (field == p)
        debugx(1, DBG_ERR, "missing host/address");

    peer->host = stringcopy(field, p - field);
    if (ipv6) {
        p++;
        if (*p && *p != ':' && *p != ' ' && *p != '\t' && *p != '\n')
            debugx(1, DBG_ERR, "unexpected character after ]");
    }
    if (*p == ':') {
            /* port number or service name is specified */;
            field = ++p;
            for (; *p && *p != ' ' && *p != '\t' && *p != '\n'; p++);
            if (field == p)
                debugx(1, DBG_ERR, "syntax error, : but no following port");
            peer->port = stringcopy(field, p - field);
    } else
        peer->port = stringcopy(peer->type == 'U' ? DEFAULT_UDP_PORT : DEFAULT_TLS_PORT, 0);
    return p;
}

FILE *openconfigfile(const char *filename) {
    FILE *f;
    char pathname[100], *base = NULL;
    
    f = fopen(filename, "r");
    if (f) {
        debug(DBG_DBG, "reading config file %s", filename);
        return f;
    }

    if (strlen(filename) + 1 <= sizeof(pathname)) {
        /* basename() might modify the string */
        strcpy(pathname, filename);
        base = basename(pathname);
        f = fopen(base, "r");
    }

    if (!f)
        debugx(1, DBG_ERR, "could not read config file %s nor %s\n%s", filename, base, strerror(errno));
    
    debug(DBG_DBG, "reading config file %s", base);
    return f;
}

struct peer *server_create(char type) {
    struct peer *server;
    char *conf;

    server = malloc(sizeof(struct peer));
    if (!server)
        debugx(1, DBG_ERR, "malloc failed");
    memset(server, 0, sizeof(struct peer));
    server->type = type;
    conf = (type == 'T' ? options.listentcp : options.listenudp);
    if (conf) {
        parsehostport(conf, server);
        if (!strcmp(server->host, "*")) {
            free(server->host);
            server->host = NULL;
        }
    } else
        server->port = stringcopy(type == 'T' ? DEFAULT_TLS_PORT : DEFAULT_UDP_PORT, 0);
    if (!resolvepeer(server, AI_PASSIVE))
        debugx(1, DBG_ERR, "failed to resolve host %s port %s, exiting", server->host, server->port);
    return server;
}

/* returns NULL on error, where to continue parsing if token and ok. E.g. "" will return token with empty string */
char *strtokenquote(char *s, char **token, char *del, char *quote, char *comment) {
    char *t = s, *q, *r;

    if (!t || !token || !del)
        return NULL;
    while (*t && strchr(del, *t))
        t++;
    if (!*t || (comment && strchr(comment, *t))) {
        *token = NULL;
        return t + 1; /* needs to be non-NULL, but value doesn't matter */
    }
    if (quote && (q = strchr(quote, *t))) {
        t++;
        r = t;
        while (*t && *t != *q)
            t++;
        if (!*t || (t[1] && !strchr(del, t[1])))
            return NULL;
        *t = '\0';
        *token = r;
        return t + 1;
    }
    *token = t;
    t++;
    while (*t && !strchr(del, *t))
        t++;
    *t = '\0';
    return t + 1;
}

/* Parses config with following syntax:
 * One of these:
 * option-name value
 * option-name = value
 * Or:
 * option-name value {
 *     option-name [=] value
 *     ...
 * }
 */
void getgeneralconfig(FILE *f, char *block, ...) {
    va_list ap;
    char line[1024];
    /* initialise lots of stuff to avoid stupid compiler warnings */
    char *tokens[3], *s, *opt = NULL, *val = NULL, *word, *optval, **str = NULL;
    int type = 0, tcount, conftype = 0;
    void (*cbk)(FILE *, char *, char *, char *) = NULL;
        
    while (fgets(line, 1024, f)) {
        s = line;
        for (tcount = 0; tcount < 3; tcount++) {
            s = strtokenquote(s, &tokens[tcount], " \t\n", "\"'", tcount ? NULL : "#");
            if (!s)
                debugx(1, DBG_ERR, "Syntax error in line starting with: %s", line);
            if (!tokens[tcount])
                break;
        }
        if (!tcount || **tokens == '#')
            continue;

        if (**tokens == '}') {
            if (block)
                return;
            debugx(1, DBG_ERR, "configuration error, found } with no matching {");
        }
            
        switch (tcount) {
        case 2:
            opt = tokens[0];
            val = tokens[1];
            conftype = CONF_STR;
            break;
        case 3:
            if (tokens[1][0] == '=' && tokens[1][1] == '\0') {
                opt = tokens[0];
                val = tokens[2];
                conftype = CONF_STR;
                break;
            }
            if (tokens[2][0] == '{' && tokens[2][1] == '\0') {
                opt = tokens[0];
                val = tokens[1];
                conftype = CONF_CBK;
                break;
            }
            /* fall through */
        default:
            if (block)
                debugx(1, DBG_ERR, "configuration error in block %s, line starting with %s", block, tokens[0]);
            debugx(1, DBG_ERR, "configuration error, syntax error in line starting with %s", tokens[0]);
        }

        if (!*val)
            debugx(1, DBG_ERR, "configuration error, option %s needs a non-empty value", opt);
        
        va_start(ap, block);
        while ((word = va_arg(ap, char *))) {
            type = va_arg(ap, int);
            switch (type) {
            case CONF_STR:
                str = va_arg(ap, char **);
                if (!str)
                    debugx(1, DBG_ERR, "getgeneralconfig: internal parameter error");
                break;
            case CONF_CBK:
                cbk = va_arg(ap, void (*)(FILE *, char *, char *, char *));
                break;
            default:
                debugx(1, DBG_ERR, "getgeneralconfig: internal parameter error");
            }
            if (!strcasecmp(opt, word))
                break;
        }
        va_end(ap);
        
        if (!word) {
            if (block)
                debugx(1, DBG_ERR, "configuration error in block %s, unknown option %s", block, opt);
            debugx(1, DBG_ERR, "configuration error, unknown option %s", opt);
        }

        if (type != conftype) {
            if (block)
                debugx(1, DBG_ERR, "configuration error in block %s, wrong syntax for option %s", block, opt);
            debugx(1, DBG_ERR, "configuration error, wrong syntax for option %s", opt);
        }
        
        switch (type) {
        case CONF_STR:
            if (block)
                debug(DBG_DBG, "getgeneralconfig: block %s: %s = %s", block, opt, val);
            else 
                debug(DBG_DBG, "getgeneralconfig: %s = %s", opt, val);
            *str = stringcopy(val, 0);
            break;
        case CONF_CBK:
            optval = malloc(strlen(opt) + strlen(val) + 2);
            if (!optval)
                debugx(1, DBG_ERR, "malloc failed");
            sprintf(optval, "%s %s", opt, val);
            cbk(f, optval, opt, val);
            free(optval);
            break;
        default:
            debugx(1, DBG_ERR, "getgeneralconfig: internal parameter error");
        }
    }
}

void confclsrv_cb(FILE *f, char *block, char *opt, char *val) {
    char *type = NULL, *secret = NULL, *port = NULL, *tls = NULL, *statusserver = NULL;
    struct client *client = NULL;
    struct server *server = NULL;
    struct peer *peer;
    
    debug(DBG_DBG, "confclsrv_cb called for %s", block);
    
    if (!strcasecmp(opt, "client")) {
        getgeneralconfig(f, block,
                         "type", CONF_STR, &type,
                         "secret", CONF_STR, &secret,
                         "tls", CONF_STR, &tls,
                         NULL
                         );
        client_count++;
        clients = realloc(clients, client_count * sizeof(struct client));
        if (!clients)
            debugx(1, DBG_ERR, "malloc failed");
        client = clients + client_count - 1;
        memset(client, 0, sizeof(struct client));
        peer = &client->peer;
    } else {
        getgeneralconfig(f, block,
                         "type", CONF_STR, &type,
                         "secret", CONF_STR, &secret,
                         "port", CONF_STR, &port,
                         "tls", CONF_STR, &tls,
                         "StatusServer", CONF_STR, &statusserver,
                         NULL
                         );
        server_count++;
        servers = realloc(servers, server_count * sizeof(struct server));
        if (!servers)
            debugx(1, DBG_ERR, "malloc failed");
        server = servers + server_count - 1;
        memset(server, 0, sizeof(struct server));
        peer = &server->peer;
        peer->port = port;
        if (statusserver) {
            if (!strcasecmp(statusserver, "on"))
                server->statusserver = 1;
            else if (strcasecmp(statusserver, "off"))
                debugx(1, DBG_ERR, "error in block %s, StatusServer is %s, must be on or off", block, statusserver);
            free(statusserver);
        }
    }
    
    peer->host = stringcopy(val, 0);
    
    if (type && !strcasecmp(type, "udp")) {
        peer->type = 'U';
        if (client)
            client_udp_count++;
        else {
            server_udp_count++;
            if (!port)
                peer->port = stringcopy(DEFAULT_UDP_PORT, 0);
        }
    } else if (type && !strcasecmp(type, "tls")) {
        if (client) {
            peer->ssl_ctx = tls ? tlsgetctx(tls, NULL) : tlsgetctx("defaultclient", "default");
            client_tls_count++;
        } else {
            peer->ssl_ctx = tls ? tlsgetctx(tls, NULL) : tlsgetctx("defaultserver", "default");
            server_tls_count++;
            if (!port)
                peer->port = stringcopy(DEFAULT_TLS_PORT, 0);
        }
        if (!peer->ssl_ctx)
            debugx(1, DBG_ERR, "error in block %s, no tls context defined", block);
        peer->type = 'T';
    } else
        debugx(1, DBG_ERR, "error in block %s, type must be set to UDP or TLS", block);
    free(type);
    
    if (!resolvepeer(peer, 0))
        debugx(1, DBG_ERR, "failed to resolve host %s port %s, exiting", peer->host, peer->port);
    
    if (!secret) {
        if (peer->type == 'U')
            debugx(1, DBG_ERR, "error in block %s, secret must be specified for UDP", block);
        peer->secret = stringcopy(DEFAULT_TLS_SECRET, 0);
    } else {
        peer->secret = secret;
    }

    if (client) {
        if (peer->type == 'U')
            client->replyq = &udp_server_replyq;
        else {
            client->replyq = malloc(sizeof(struct replyq));
            if (!client->replyq)
                debugx(1, DBG_ERR, "malloc failed");
            client->replyq->replies = calloc(MAX_REQUESTS, sizeof(struct reply));
            if (!client->replyq->replies)
                debugx(1, DBG_ERR, "malloc failed");
            client->replyq->size = MAX_REQUESTS;
            client->replyq->count = 0;
            pthread_mutex_init(&client->replyq->count_mutex, NULL);
            pthread_cond_init(&client->replyq->count_cond, NULL);
        }
    } else {
        pthread_mutex_init(&server->lock, NULL);
        server->sock = -1;
        server->requests = calloc(MAX_REQUESTS, sizeof(struct request));
        if (!server->requests)
            debugx(1, DBG_ERR, "malloc failed");
        server->newrq = 0;
        pthread_mutex_init(&server->newrq_mutex, NULL);
        pthread_cond_init(&server->newrq_cond, NULL);
    }
}

void confrealm_cb(FILE *f, char *block, char *opt, char *val) {
    char *server = NULL, *msg = NULL;
    
    debug(DBG_DBG, "confrealm_cb called for %s", block);
    
    getgeneralconfig(f, block,
                     "server", CONF_STR, &server,
                     "ReplyMessage", CONF_STR, &msg,
                     NULL
                     );

    addrealm(val, server, msg);
    free(server);
}

void conftls_cb(FILE *f, char *block, char *opt, char *val) {
    char *cacertfile = NULL, *cacertpath = NULL, *certfile = NULL, *certkeyfile = NULL, *certkeypwd = NULL;
    
    debug(DBG_DBG, "conftls_cb called for %s", block);
    
    getgeneralconfig(f, block,
                     "CACertificateFile", CONF_STR, &cacertfile,
                     "CACertificatePath", CONF_STR, &cacertpath,
                     "CertificateFile", CONF_STR, &certfile,
                     "CertificateKeyFile", CONF_STR, &certkeyfile,
                     "CertificateKeyPassword", CONF_STR, &certkeypwd,
                     NULL
                     );
    
    tlsadd(val, cacertfile, cacertpath, certfile, certkeyfile, certkeypwd);
    free(cacertfile);
    free(cacertpath);
    free(certfile);
    free(certkeyfile);
    free(certkeypwd);
}

void getmainconfig(const char *configfile) {
    FILE *f;
    char *loglevel = NULL;

    f = openconfigfile(configfile);
    memset(&options, 0, sizeof(options));

    getgeneralconfig(f, NULL,
                     "ListenUDP", CONF_STR, &options.listenudp,
                     "ListenTCP", CONF_STR, &options.listentcp,
                     "LogLevel", CONF_STR, &loglevel,
                     "LogDestination", CONF_STR, &options.logdestination,
                     "Client", CONF_CBK, confclsrv_cb,
                     "Server", CONF_CBK, confclsrv_cb,
                     "Realm", CONF_CBK, confrealm_cb,
                     "TLS", CONF_CBK, conftls_cb,
                     NULL
                     );
    fclose(f);
    tlsfree();
    
    if (loglevel) {
        if (strlen(loglevel) != 1 || *loglevel < '1' || *loglevel > '4')
            debugx(1, DBG_ERR, "error in %s, value of option LogLevel is %s, must be 1, 2, 3 or 4", configfile, loglevel);
        options.loglevel = *loglevel - '0';
        free(loglevel);
    }

    if (client_udp_count) {
        udp_server_replyq.replies = malloc(client_udp_count * MAX_REQUESTS * sizeof(struct reply));
        if (!udp_server_replyq.replies)
            debugx(1, DBG_ERR, "malloc failed");
        udp_server_replyq.size = client_udp_count * MAX_REQUESTS;
        udp_server_replyq.count = 0;
        pthread_mutex_init(&udp_server_replyq.count_mutex, NULL);
        pthread_cond_init(&udp_server_replyq.count_cond, NULL);
    }    
}

void getargs(int argc, char **argv, uint8_t *foreground, uint8_t *loglevel, char **configfile) {
    int c;

    while ((c = getopt(argc, argv, "c:d:fv")) != -1) {
        switch (c) {
        case 'c':
            *configfile = optarg;
            break;
        case 'd':
            if (strlen(optarg) != 1 || *optarg < '1' || *optarg > '4')
                debugx(1, DBG_ERR, "Debug level must be 1, 2, 3 or 4, not %s", optarg);
            *loglevel = *optarg - '0';
            break;
        case 'f':
            *foreground = 1;
            break;
        case 'v':
                debugx(0, DBG_ERR, "radsecproxy revision $Rev$");
        default:
            goto usage;
        }
    }
    if (!(argc - optind))
        return;

 usage:
    debug(DBG_ERR, "Usage:\n%s [ -c configfile ] [ -d debuglevel ] [ -f ] [ -v ]", argv[0]);
    exit(1);
}

int main(int argc, char **argv) {
    pthread_t udpserverth;
    int i;
    uint8_t foreground = 0, loglevel = 0;
    char *configfile = NULL;
    
    debug_init("radsecproxy");
    debug_set_level(DEBUG_LEVEL);
    getargs(argc, argv, &foreground, &loglevel, &configfile);
    if (loglevel)
        debug_set_level(loglevel);
    debug(DBG_INFO, "radsecproxy revision $Rev$ starting");
    getmainconfig(configfile ? configfile : CONFIG_MAIN);
    if (loglevel)
        options.loglevel = loglevel;
    else if (options.loglevel)
        debug_set_level(options.loglevel);
    if (foreground)
        options.logdestination = NULL;
    else {
        if (!options.logdestination)
            options.logdestination = "x-syslog:///";
        debug_set_destination(options.logdestination);
    }

    if (!server_count)
        debugx(1, DBG_ERR, "No servers configured, nothing to do, exiting");
    if (!client_count)
        debugx(1, DBG_ERR, "No clients configured, nothing to do, exiting");
    if (!realm_count)
        debugx(1, DBG_ERR, "No realms configured, nothing to do, exiting");

    if (!foreground && (daemon(0, 0) < 0))
        debugx(1, DBG_ERR, "daemon() failed: %s", strerror(errno));
        
    if (client_udp_count) {
        udp_server_listen = server_create('U');
        if (pthread_create(&udpserverth, NULL, udpserverrd, NULL))
            debugx(1, DBG_ERR, "pthread_create failed");
    }
    
    for (i = 0; i < server_count; i++)
        if (pthread_create(&servers[i].clientth, NULL, clientwr, (void *)&servers[i]))
            debugx(1, DBG_ERR, "pthread_create failed");

    if (client_tls_count) {
        tcp_server_listen = server_create('T');
        return tlslistener();
    }
    
    /* just hang around doing nothing, anything to do here? */
    for (;;)
        sleep(1000);
}