diff options
Diffstat (limited to 'dtls.c')
| -rw-r--r-- | dtls.c | 473 |
1 files changed, 473 insertions, 0 deletions
@@ -0,0 +1,473 @@ +/* + * Copyright (C) 2008 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. + */ + +#include <signal.h> +#include <sys/socket.h> +#include <netinet/in.h> +#include <netdb.h> +#include <string.h> +#include <unistd.h> +#include <limits.h> +#ifdef SYS_SOLARIS9 +#include <fcntl.h> +#endif +#include <sys/time.h> +#include <sys/types.h> +#include <sys/select.h> +#include <ctype.h> +#include <sys/wait.h> +#include <arpa/inet.h> +#include <regex.h> +#include <pthread.h> +#include <openssl/ssl.h> +#include <openssl/err.h> +#include "debug.h" +#include "list.h" +#include "util.h" +#include "radsecproxy.h" +#include "dtls.h" + +int udp2bio(int s, struct queue *q, int cnt) { + unsigned char *buf; + BIO *rbio; + + if (cnt < 1) + return 0; + + buf = malloc(cnt); + if (!buf) { + unsigned char err; + debug(DBG_ERR, "udp2bio: malloc failed"); + recv(s, &err, 1, 0); + return 0; + } + + cnt = recv(s, buf, cnt, 0); + if (cnt < 1) { + debug(DBG_WARN, "udp2bio: recv failed"); + free(buf); + return 0; + } + + rbio = BIO_new_mem_buf(buf, cnt); + BIO_set_mem_eof_return(rbio, -1); + + pthread_mutex_lock(&q->mutex); + if (!list_push(q->entries, rbio)) { + BIO_free(rbio); + pthread_mutex_unlock(&q->mutex); + return 0; + } + pthread_cond_signal(&q->cond); + pthread_mutex_unlock(&q->mutex); + return 1; +} + +BIO *getrbio(SSL *ssl, struct queue *q, int timeout) { + BIO *rbio; + struct timeval now; + struct timespec to; + + pthread_mutex_lock(&q->mutex); + if (!(rbio = (BIO *)list_shift(q->entries))) { + if (timeout) { + gettimeofday(&now, NULL); + memset(&to, 0, sizeof(struct timespec)); + to.tv_sec = now.tv_sec + timeout; + pthread_cond_timedwait(&q->cond, &q->mutex, &to); + } else + pthread_cond_wait(&q->cond, &q->mutex); + rbio = (BIO *)list_shift(q->entries); + } + pthread_mutex_unlock(&q->mutex); + return rbio; +} + +void *udpdtlsserverrd(void *arg) { + int cnt, s = *(int *)arg; + unsigned char buf[4]; + struct sockaddr_storage from; + socklen_t fromlen = sizeof(from); + struct clsrvconf *conf; + struct list_node *node; + struct client *client; + fd_set readfds; + pthread_t dtlsserverth; + + for (;;) { + FD_ZERO(&readfds); + FD_SET(s, &readfds); + if (select(s + 1, &readfds, NULL, NULL, NULL) < 1) + continue; + cnt = recvfrom(s, buf, 4, MSG_PEEK | MSG_TRUNC, (struct sockaddr *)&from, &fromlen); + if (cnt == -1) { + debug(DBG_WARN, "udpdtlsserverrd: recv failed"); + continue; + } + conf = find_clconf(RAD_DTLS, (struct sockaddr *)&from, NULL); + if (!conf) { + debug(DBG_WARN, "udpdtlsserverrd: got packet from wrong or unknown DTLS peer %s, ignoring", addr2string((struct sockaddr *)&from, fromlen)); + recv(s, buf, 4, 0); + continue; + } + + node = list_first(conf->clients); + if (node) + client = (struct client *)node->data; + else { + client = addclient(conf); + if (!client) { + recv(s, buf, 4, 0); + continue; + } + client->sock = s; + memcpy(&client->addr, &from, fromlen); + if (pthread_create(&dtlsserverth, NULL, dtlsservernew, (void *)client)) { + debug(DBG_ERR, "udpdtlsserverrd: pthread_create failed"); + removeclient(client); + recv(s, buf, 4, 0); + continue; + } + pthread_detach(dtlsserverth); + } + if (udp2bio(s, client->rbios, cnt)) + debug(DBG_DBG, "udpdtlsserverrd: got DTLS in UDP from %s", addr2string((struct sockaddr *)&from, fromlen)); + } +} + +void *dtlsserverwr(void *arg) { + int cnt; + unsigned long error; + struct client *client = (struct client *)arg; + struct queue *replyq; + struct reply *reply; + + debug(DBG_DBG, "dtlsserverwr: starting for %s", client->conf->host); + replyq = client->replyq; + for (;;) { + pthread_mutex_lock(&replyq->mutex); + while (!list_first(replyq->entries)) { + if (client->ssl) { + debug(DBG_DBG, "dtlsserverwr: waiting for signal"); + pthread_cond_wait(&replyq->cond, &replyq->mutex); + debug(DBG_DBG, "dtlsserverwr: got signal"); + } + if (!client->ssl) { + /* ssl might have changed while waiting */ + pthread_mutex_unlock(&replyq->mutex); + debug(DBG_DBG, "dtlsserverwr: exiting as requested"); + ERR_remove_state(0); + pthread_exit(NULL); + } + } + reply = (struct reply *)list_shift(replyq->entries); + pthread_mutex_unlock(&replyq->mutex); + cnt = SSL_write(client->ssl, reply->buf, RADLEN(reply->buf)); + if (cnt > 0) + debug(DBG_DBG, "dtlsserverwr: sent %d bytes, Radius packet of length %d", + cnt, RADLEN(reply->buf)); + else + while ((error = ERR_get_error())) + debug(DBG_ERR, "dtlsserverwr: SSL: %s", ERR_error_string(error, NULL)); + free(reply->buf); + free(reply); + } +} + +int dtlsread(SSL *ssl, struct queue *q, unsigned char *buf, int num) { + int len, cnt; + + for (len = 0; len < num; len += cnt) { + cnt = SSL_read(ssl, buf + len, num - len); + if (cnt <= 0) + switch (cnt = SSL_get_error(ssl, cnt)) { + case SSL_ERROR_WANT_READ: + BIO_free(ssl->rbio); + ssl->rbio = getrbio(ssl, q, 0); + if (!ssl->rbio) + return -1; + cnt = 0; + continue; + case SSL_ERROR_WANT_WRITE: + cnt = 0; + continue; + case SSL_ERROR_ZERO_RETURN: + /* remote end sent close_notify, send one back */ + SSL_shutdown(ssl); + return -1; + default: + return -1; + } + } + return num; +} + +unsigned char *raddtlsget(SSL *ssl, struct queue *rbios) { + int cnt, len; + unsigned char buf[4], *rad; + + for (;;) { + cnt = dtlsread(ssl, rbios, buf, 4); + if (cnt < 1) { + debug(DBG_DBG, "raddtlsget: connection lost"); + return NULL; + } + + len = RADLEN(buf); + rad = malloc(len); + if (!rad) { + debug(DBG_ERR, "raddtlsget: malloc failed"); + continue; + } + memcpy(rad, buf, 4); + + cnt = dtlsread(ssl, rbios, rad + 4, len - 4); + if (cnt < 1) { + debug(DBG_DBG, "raddtlsget: connection lost"); + free(rad); + return NULL; + } + + if (len >= 20) + break; + + free(rad); + debug(DBG_WARN, "raddtlsget: packet smaller than minimum radius size"); + } + + debug(DBG_DBG, "raddtlsget: got %d bytes", len); + return rad; +} + +void dtlsserverrd(struct client *client) { + struct request rq; + pthread_t dtlsserverwrth; + + debug(DBG_DBG, "dtlsserverrd: starting for %s", client->conf->host); + + if (pthread_create(&dtlsserverwrth, NULL, dtlsserverwr, (void *)client)) { + debug(DBG_ERR, "dtlsserverrd: pthread_create failed"); + return; + } + + for (;;) { + memset(&rq, 0, sizeof(struct request)); + rq.buf = raddtlsget(client->ssl, client->rbios); + if (!rq.buf) { + debug(DBG_ERR, "dtlsserverrd: connection from %s lost", client->conf->host); + break; + } + debug(DBG_DBG, "dtlsserverrd: got Radius message from %s", client->conf->host); + rq.from = client; + if (!radsrv(&rq)) { + debug(DBG_ERR, "dtlsserverrd: message authentication/validation failed, closing connection from %s", client->conf->host); + break; + } + } + + /* stop writer by setting ssl to NULL and give signal in case waiting for data */ + client->ssl = NULL; + + pthread_mutex_lock(&client->replyq->mutex); + pthread_cond_signal(&client->replyq->cond); + pthread_mutex_unlock(&client->replyq->mutex); + debug(DBG_DBG, "dtlsserverrd: waiting for writer to end"); + pthread_join(dtlsserverwrth, NULL); + removeclientrqs(client); + debug(DBG_DBG, "dtlsserverrd: reader for %s exiting", client->conf->host); +} + +/* accept if acc == 1, else connect */ +SSL *dtlsacccon(uint8_t acc, SSL_CTX *ctx, int s, struct sockaddr *addr, struct queue *rbios) { + SSL *ssl; + int i, res; + unsigned long error; + BIO *mem0bio, *wbio; + + ssl = SSL_new(ctx); + if (!ssl) + return NULL; + + mem0bio = BIO_new(BIO_s_mem()); + BIO_set_mem_eof_return(mem0bio, -1); + wbio = BIO_new_dgram(s, BIO_NOCLOSE); + BIO_dgram_set_peer(wbio, addr); + SSL_set_bio(ssl, mem0bio, wbio); + + for (i = 0; i < 5; i++) { + res = acc ? SSL_accept(ssl) : SSL_connect(ssl); + if (res > 0) + return ssl; + if (res == 0) + break; + if (SSL_get_error(ssl, res) == SSL_ERROR_WANT_READ) { + BIO_free(ssl->rbio); + ssl->rbio = getrbio(ssl, rbios, 5); + if (!ssl->rbio) + break; + } + while ((error = ERR_get_error())) + debug(DBG_ERR, "dtls%st: DTLS: %s", acc ? "accep" : "connec", ERR_error_string(error, NULL)); + } + + SSL_free(ssl); + return NULL; +} + +void *dtlsservernew(void *arg) { + struct client *client = (struct client *)arg; + X509 *cert = NULL; + + client->ssl = dtlsacccon(1, client->conf->ssl_ctx, client->sock, (struct sockaddr *)&client->addr, client->rbios); + if (!client->ssl) + goto exit; + cert = verifytlscert(client->ssl); + if (!cert) + goto exit; + if (verifyconfcert(cert, client->conf)) { + X509_free(cert); + dtlsserverrd(client); + removeclient(client); + } else + debug(DBG_WARN, "dtlsservernew: ignoring request, certificate validation failed"); + if (cert) + X509_free(cert); + + exit: + SSL_free(client->ssl); + ERR_remove_state(0); + pthread_exit(NULL); +} + +int dtlsconnect(struct server *server, struct timeval *when, int timeout, char *text) { + struct timeval now; + time_t elapsed; + X509 *cert; + + debug(DBG_DBG, "dtlsconnect: 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, "dtlsconnect(%s): seems already reconnected", text); + pthread_mutex_unlock(&server->lock); + return 1; + } + + for (;;) { + gettimeofday(&now, NULL); + elapsed = now.tv_sec - server->lastconnecttry.tv_sec; + + if (timeout && server->lastconnecttry.tv_sec && elapsed > timeout) { + debug(DBG_DBG, "dtlsconnect: timeout"); + SSL_free(server->ssl); + server->ssl = NULL; + pthread_mutex_unlock(&server->lock); + return 0; + } + + if (server->connectionok) { + server->connectionok = 0; + sleep(2); + } else if (elapsed < 1) + sleep(2); + else if (elapsed < 60) { + debug(DBG_INFO, "dtlsconnect: sleeping %lds", elapsed); + sleep(elapsed); + } else if (elapsed < 100000) { + debug(DBG_INFO, "dtlsconnect: sleeping %ds", 60); + sleep(60); + } else + server->lastconnecttry.tv_sec = now.tv_sec; /* no sleep at startup */ + debug(DBG_WARN, "dtlsconnect: trying to open DTLS connection to %s port %s", server->conf->host, server->conf->port); + + SSL_free(server->ssl); + server->ssl = dtlsacccon(0, server->conf->ssl_ctx, server->sock, server->conf->addrinfo->ai_addr, server->rbios); + if (!server->ssl) + continue; + debug(DBG_DBG, "dtlsconnect: DTLS: ok"); + + cert = verifytlscert(server->ssl); + if (!cert) + continue; + + if (verifyconfcert(cert, server->conf)) + break; + X509_free(cert); + } + X509_free(cert); + debug(DBG_WARN, "dtlsconnect: DTLS connection to %s port %s up", server->conf->host, server->conf->port); + gettimeofday(&server->lastconnecttry, NULL); + pthread_mutex_unlock(&server->lock); + return 1; +} + +int clientradputdtls(struct server *server, unsigned char *rad) { + int cnt; + size_t len; + unsigned long error; + struct clsrvconf *conf = server->conf; + + len = RADLEN(rad); + while ((cnt = SSL_write(server->ssl, rad, len)) <= 0) { + while ((error = ERR_get_error())) + debug(DBG_ERR, "clientradputdtls: DTLS: %s", ERR_error_string(error, NULL)); + } + debug(DBG_DBG, "clientradputdtls: Sent %d bytes, Radius packet of length %d to DTLS peer %s", cnt, len, conf->host); + return 1; +} + +/* reads UDP containing DTLS and passes it on to dtlsclientrd */ +void *udpdtlsclientrd(void *arg) { + int cnt, s = *(int *)arg; + unsigned char buf[4]; + struct sockaddr_storage from; + socklen_t fromlen = sizeof(from); + struct clsrvconf *conf; + fd_set readfds; + + for (;;) { + FD_ZERO(&readfds); + FD_SET(s, &readfds); + if (select(s + 1, &readfds, NULL, NULL, NULL) < 1) + continue; + cnt = recvfrom(s, buf, 4, MSG_PEEK | MSG_TRUNC, (struct sockaddr *)&from, &fromlen); + if (cnt == -1) { + debug(DBG_WARN, "udpdtlsclientrd: recv failed"); + continue; + } + + conf = find_srvconf(RAD_DTLS, (struct sockaddr *)&from, NULL); + if (!conf) { + debug(DBG_WARN, "udpdtlsclientrd: got packet from wrong or unknown DTLS peer %s, ignoring", addr2string((struct sockaddr *)&from, fromlen)); + recv(s, buf, 4, 0); + continue; + } + if (udp2bio(s, conf->servers->rbios, cnt)) + debug(DBG_DBG, "radudpget: got DTLS in UDP from %s", addr2string((struct sockaddr *)&from, fromlen)); + } +} + +void *dtlsclientrd(void *arg) { + struct server *server = (struct server *)arg; + unsigned char *buf; + struct timeval lastconnecttry; + + for (;;) { + /* yes, lastconnecttry is really necessary */ + lastconnecttry = server->lastconnecttry; + buf = raddtlsget(server->ssl, server->rbios); + if (!buf) { + dtlsconnect(server, &lastconnecttry, 0, "dtlsclientrd"); + continue; + } + + if (!replyh(server, buf)) + free(buf); + } +} + |