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stud.c
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stud.c
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/**
* Copyright 2011 Bump Technologies, Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification, are
* permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this list of
* conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice, this list
* of conditions and the following disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY BUMP TECHNOLOGIES, INC. ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BUMP TECHNOLOGIES, INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* The views and conclusions contained in the software and documentation are those of the
* authors and should not be interpreted as representing official policies, either expressed
* or implied, of Bump Technologies, Inc.
*
**/
#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <netdb.h>
#include <sys/wait.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <net/if.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <getopt.h>
#include <pwd.h>
#include <limits.h>
#include <syslog.h>
#include <stdarg.h>
#include <ctype.h>
#include <sched.h>
#include <signal.h>
#include <openssl/ssl.h>
#include <openssl/x509.h>
#include <openssl/x509v3.h>
#include <openssl/x509.h>
#include <openssl/err.h>
#include <openssl/engine.h>
#include <openssl/asn1.h>
#include <ev.h>
#include "ringbuffer.h"
#include "shctx.h"
#include "configuration.h"
#ifndef MSG_NOSIGNAL
# define MSG_NOSIGNAL 0
#endif
#ifndef AI_ADDRCONFIG
# define AI_ADDRCONFIG 0
#endif
/* For Mac OS X */
#ifndef TCP_KEEPIDLE
# ifdef TCP_KEEPALIVE
# define TCP_KEEPIDLE TCP_KEEPALIVE
# endif
#endif
#ifndef SOL_TCP
# define SOL_TCP IPPROTO_TCP
#endif
/* Do we have SNI support? */
#ifndef OPENSSL_NO_TLSEXT
#ifndef SSL_CTRL_SET_TLSEXT_HOSTNAME
#define OPENSSL_NO_TLSEXT
#endif
#endif
/* Globals */
static struct ev_loop *loop;
static struct addrinfo *backaddr;
static pid_t master_pid;
static ev_io listener;
static int listener_socket;
static int child_num;
static pid_t *child_pids;
static SSL_CTX *default_ctx;
static SSL_SESSION *client_session;
#ifdef USE_SHARED_CACHE
static ev_io shcupd_listener;
static int shcupd_socket;
struct addrinfo *shcupd_peers[MAX_SHCUPD_PEERS+1];
static unsigned char shared_secret[SHA_DIGEST_LENGTH];
#endif /*USE_SHARED_CACHE*/
long openssl_version;
int create_workers;
stud_config *CONFIG;
static char tcp_proxy_line[128] = "";
/* What agent/state requests the shutdown--for proper half-closed
* handling */
typedef enum _SHUTDOWN_REQUESTOR {
SHUTDOWN_HARD,
SHUTDOWN_CLEAR,
SHUTDOWN_SSL
} SHUTDOWN_REQUESTOR;
#ifndef OPENSSL_NO_TLSEXT
/*
* SSL context linked list. Someday it might be nice to have a more clever data
* structure here, but assuming the number of SNI certs is small it probably
* doesn't matter.
*/
typedef struct ctx_list {
char *servername;
SSL_CTX *ctx;
struct ctx_list *next;
} ctx_list;
static ctx_list *sni_ctxs;
#endif /* OPENSSL_NO_TLSEXT */
/*
* Proxied State
*
* All state associated with one proxied connection
*/
typedef struct proxystate {
ringbuffer ring_ssl2clear; /* Pushing bytes from secure to clear stream */
ringbuffer ring_clear2ssl; /* Pushing bytes from clear to secure stream */
ev_io ev_r_ssl; /* Secure stream write event */
ev_io ev_w_ssl; /* Secure stream read event */
ev_io ev_r_handshake; /* Secure stream handshake write event */
ev_io ev_w_handshake; /* Secure stream handshake read event */
ev_io ev_w_connect; /* Backend connect event */
ev_io ev_r_clear; /* Clear stream write event */
ev_io ev_w_clear; /* Clear stream read event */
ev_io ev_proxy; /* proxy read event */
int fd_up; /* Upstream (client) socket */
int fd_down; /* Downstream (backend) socket */
int want_shutdown:1; /* Connection is half-shutdown */
int handshaked:1; /* Initial handshake happened */
int clear_connected:1; /* Clear stream is connected */
int renegotiation:1; /* Renegotation is occuring */
SSL *ssl; /* OpenSSL SSL state */
struct sockaddr_storage remote_ip; /* Remote ip returned from `accept` */
} proxystate;
#define LOG(...) \
do { \
if (!CONFIG->QUIET) fprintf(stdout, __VA_ARGS__); \
if (CONFIG->SYSLOG) syslog(LOG_INFO, __VA_ARGS__); \
} while(0)
#define ERR(...) \
do { \
fprintf(stderr, __VA_ARGS__); \
if (CONFIG->SYSLOG) syslog(LOG_ERR, __VA_ARGS__); \
} while(0)
#define NULL_DEV "/dev/null"
/* Set a file descriptor (socket) to non-blocking mode */
static void setnonblocking(int fd) {
int flag = 1;
assert(ioctl(fd, FIONBIO, &flag) == 0);
}
/* set a tcp socket to use TCP Keepalive */
static void settcpkeepalive(int fd) {
int optval = 1;
socklen_t optlen = sizeof(optval);
if(setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, &optval, optlen) < 0) {
ERR("Error activating SO_KEEPALIVE on client socket: %s", strerror(errno));
}
optval = CONFIG->TCP_KEEPALIVE_TIME;
optlen = sizeof(optval);
#ifdef TCP_KEEPIDLE
if(setsockopt(fd, SOL_TCP, TCP_KEEPIDLE, &optval, optlen) < 0) {
ERR("Error setting TCP_KEEPIDLE on client socket: %s", strerror(errno));
}
#endif
}
static void fail(const char* s) {
perror(s);
exit(1);
}
void die (char *fmt, ...) {
va_list args;
va_start(args, fmt);
vfprintf(stderr, fmt, args);
va_end(args);
exit(1);
}
#ifndef OPENSSL_NO_DH
static int init_dh(SSL_CTX *ctx, const char *cert) {
DH *dh;
BIO *bio;
assert(cert);
bio = BIO_new_file(cert, "r");
if (!bio) {
ERR_print_errors_fp(stderr);
return -1;
}
dh = PEM_read_bio_DHparams(bio, NULL, NULL, NULL);
BIO_free(bio);
if (!dh) {
ERR("{core} Note: no DH parameters found in %s\n", cert);
return -1;
}
LOG("{core} Using DH parameters from %s\n", cert);
SSL_CTX_set_tmp_dh(ctx, dh);
LOG("{core} DH initialized with %d bit key\n", 8*DH_size(dh));
DH_free(dh);
#ifndef OPENSSL_NO_EC
#ifdef NID_X9_62_prime256v1
EC_KEY *ecdh = NULL;
ecdh = EC_KEY_new_by_curve_name(NID_X9_62_prime256v1);
SSL_CTX_set_tmp_ecdh(ctx, ecdh);
EC_KEY_free(ecdh);
LOG("{core} ECDH Initialized with NIST P-256\n");
#endif /* NID_X9_62_prime256v1 */
#endif /* OPENSSL_NO_EC */
return 0;
}
#endif /* OPENSSL_NO_DH */
/* This callback function is executed while OpenSSL processes the SSL
* handshake and does SSL record layer stuff. It's used to trap
* client-initiated renegotiations.
*/
static void info_callback(const SSL *ssl, int where, int ret) {
(void)ret;
if (where & SSL_CB_HANDSHAKE_START) {
proxystate *ps = (proxystate *)SSL_get_app_data(ssl);
if (ps->handshaked) {
ps->renegotiation = 1;
LOG("{core} SSL renegotiation asked by client\n");
}
}
}
#ifdef USE_SHARED_CACHE
/* Handle incoming message updates */
static void handle_shcupd(struct ev_loop *loop, ev_io *w, int revents) {
(void) revents;
unsigned char msg[SHSESS_MAX_ENCODED_LEN], hash[EVP_MAX_MD_SIZE];
ssize_t r;
unsigned int hash_len;
uint32_t encdate;
long now = (time_t)ev_now(loop);
while ( ( r = recv(w->fd, msg, sizeof(msg), 0) ) > 0 ) {
/* msg len must be greater than 1 Byte of data + sig length */
if (r < (int)(1+sizeof(shared_secret)))
continue;
/* compute sig */
r -= sizeof(shared_secret);
HMAC(EVP_sha1(), shared_secret, sizeof(shared_secret), msg, r, hash, &hash_len);
if (hash_len != sizeof(shared_secret)) /* should never append */
continue;
/* check sign */
if(memcmp(msg+r, hash, hash_len))
continue;
/* msg len must be greater than 1 Byte of data + encdate length */
if (r < (int)(1+sizeof(uint32_t)))
continue;
/* drop too unsync updates */
r -= sizeof(uint32_t);
encdate = *((uint32_t *)&msg[r]);
if (!(abs((int)(int32_t)now-ntohl(encdate)) < SSL_CTX_get_timeout(default_ctx)))
continue;
shctx_sess_add(msg, r, now);
}
}
/* Send remote updates messages callback */
void shcupd_session_new(unsigned char *msg, unsigned int len, long cdate) {
unsigned int hash_len;
struct addrinfo **pai = shcupd_peers;
uint32_t ncdate;
/* add session creation encoded date to footer */
ncdate = htonl((uint32_t)cdate);
memcpy(msg+len, &ncdate, sizeof(ncdate));
len += sizeof(ncdate);
/* add msg sign */
HMAC(EVP_sha1(), shared_secret, sizeof(shared_secret),
msg, len, msg+len, &hash_len);
len += hash_len;
/* send msg to peers */
while (*pai) {
sendto(shcupd_socket, msg, len, 0, (*pai)->ai_addr, (*pai)->ai_addrlen);
pai++;
}
}
/* Compute a sha1 secret from an ASN1 rsa private key */
static int compute_secret(RSA *rsa, unsigned char *secret) {
unsigned char *buf,*p;
unsigned int length;
length = i2d_RSAPrivateKey(rsa, NULL);
if (length <= 0)
return -1;
p = buf = (unsigned char *)malloc(length*sizeof(unsigned char));
if (!buf)
return -1;
i2d_RSAPrivateKey(rsa,&p);
SHA1(buf, length, secret);
free(buf);
return 0;
}
/* Create udp socket to receive and send updates */
static int create_shcupd_socket() {
struct addrinfo *ai, hints;
struct addrinfo **pai = shcupd_peers;
memset(&hints, 0, sizeof hints);
hints.ai_family = AF_UNSPEC;
hints.ai_socktype = SOCK_DGRAM;
hints.ai_flags = AI_PASSIVE | AI_ADDRCONFIG;
const int gai_err = getaddrinfo(CONFIG->SHCUPD_IP, CONFIG->SHCUPD_PORT,
&hints, &ai);
if (gai_err != 0) {
ERR("{getaddrinfo}: [%s]\n", gai_strerror(gai_err));
exit(1);
}
/* check if peers inet family addresses match */
while (*pai) {
if ((*pai)->ai_family != ai->ai_family) {
ERR("Share host and peers inet family differs\n");
exit(1);
}
pai++;
}
int s = socket(ai->ai_family, SOCK_DGRAM, IPPROTO_UDP);
if (s == -1)
fail("{socket: shared cache updates}");
int t = 1;
setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &t, sizeof(int));
#ifdef SO_REUSEPORT
setsockopt(s, SOL_SOCKET, SO_REUSEPORT, &t, sizeof(int));
#endif
setnonblocking(s);
if (ai->ai_addr->sa_family == AF_INET) {
struct ip_mreqn mreqn;
memset(&mreqn, 0, sizeof(mreqn));
mreqn.imr_multiaddr.s_addr = ((struct sockaddr_in *)ai->ai_addr)->sin_addr.s_addr;
if (CONFIG->SHCUPD_MCASTIF) {
if (isalpha(*CONFIG->SHCUPD_MCASTIF)) { /* appears to be an iface name */
struct ifreq ifr;
memset(&ifr, 0, sizeof(ifr));
if (strlen(CONFIG->SHCUPD_MCASTIF) > IFNAMSIZ) {
ERR("Error iface name is too long [%s]\n",CONFIG->SHCUPD_MCASTIF);
exit(1);
}
memcpy(ifr.ifr_name, CONFIG->SHCUPD_MCASTIF, strlen(CONFIG->SHCUPD_MCASTIF));
if (ioctl(s, SIOCGIFINDEX, &ifr)) {
fail("{ioctl: SIOCGIFINDEX}");
}
mreqn.imr_ifindex = ifr.ifr_ifindex;
}
else if (strchr(CONFIG->SHCUPD_MCASTIF,'.')) { /* appears to be an ipv4 address */
mreqn.imr_address.s_addr = inet_addr(CONFIG->SHCUPD_MCASTIF);
}
else { /* appears to be an iface index */
mreqn.imr_ifindex = atoi(CONFIG->SHCUPD_MCASTIF);
}
}
if (setsockopt(s, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mreqn, sizeof(mreqn)) < 0) {
if (errno != EINVAL) { /* EINVAL if it is not a multicast address,
not an error we consider unicast */
fail("{setsockopt: IP_ADD_MEMBERSIP}");
}
}
else { /* this is a multicast address */
unsigned char loop = 0;
if(setsockopt(s, IPPROTO_IP, IP_MULTICAST_LOOP, &loop, sizeof(loop)) < 0) {
fail("{setsockopt: IP_MULTICAST_LOOP}");
}
}
/* optional set sockopts for sending to multicast msg */
if (CONFIG->SHCUPD_MCASTIF &&
setsockopt(s, IPPROTO_IP, IP_MULTICAST_IF, &mreqn, sizeof(mreqn)) < 0) {
fail("{setsockopt: IP_MULTICAST_IF}");
}
if (CONFIG->SHCUPD_MCASTTTL) {
unsigned char ttl;
ttl = (unsigned char)atoi(CONFIG->SHCUPD_MCASTTTL);
if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl)) < 0) {
fail("{setsockopt: IP_MULTICAST_TTL}");
}
}
}
#ifdef IPV6_ADD_MEMBERSHIP
else if (ai->ai_addr->sa_family == AF_INET6) {
struct ipv6_mreq mreq;
memset(&mreq, 0, sizeof(mreq));
memcpy(&mreq.ipv6mr_multiaddr, &((struct sockaddr_in6 *)ai->ai_addr)->sin6_addr,
sizeof(mreq.ipv6mr_multiaddr));
if (CONFIG->SHCUPD_MCASTIF) {
if (isalpha(*CONFIG->SHCUPD_MCASTIF)) { /* appears to be an iface name */
struct ifreq ifr;
memset(&ifr, 0, sizeof(ifr));
if (strlen(CONFIG->SHCUPD_MCASTIF) > IFNAMSIZ) {
ERR("Error iface name is too long [%s]\n",CONFIG->SHCUPD_MCASTIF);
exit(1);
}
memcpy(ifr.ifr_name, CONFIG->SHCUPD_MCASTIF, strlen(CONFIG->SHCUPD_MCASTIF));
if (ioctl(s, SIOCGIFINDEX, &ifr)) {
fail("{ioctl: SIOCGIFINDEX}");
}
mreq.ipv6mr_interface = ifr.ifr_ifindex;
}
else { /* option appears to be an iface index */
mreq.ipv6mr_interface = atoi(CONFIG->SHCUPD_MCASTIF);
}
}
if (setsockopt(s, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &mreq, sizeof(mreq)) < 0) {
if (errno != EINVAL) { /* EINVAL if it is not a multicast address,
not an error we consider unicast */
fail("{setsockopt: IPV6_ADD_MEMBERSIP}");
}
}
else { /* this is a multicast address */
unsigned int loop = 0;
if(setsockopt(s, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &loop, sizeof(loop)) < 0) {
fail("{setsockopt: IPV6_MULTICAST_LOOP}");
}
}
/* optional set sockopts for sending to multicast msg */
if (setsockopt(s, IPPROTO_IPV6, IPV6_MULTICAST_IF,
&mreq.ipv6mr_interface, sizeof(mreq.ipv6mr_interface)) < 0) {
fail("{setsockopt: IPV6_MULTICAST_IF}");
}
if (CONFIG->SHCUPD_MCASTTTL) {
int hops;
hops = atoi(CONFIG->SHCUPD_MCASTTTL);
if (setsockopt(s, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &hops, sizeof(hops)) < 0) {
fail("{setsockopt: IPV6_MULTICAST_HOPS}");
}
}
}
#endif /* IPV6_ADD_MEMBERSHIP */
if (bind(s, ai->ai_addr, ai->ai_addrlen)) {
fail("{bind-socket}");
}
freeaddrinfo(ai);
return s;
}
#endif /*USE_SHARED_CACHE */
RSA *load_rsa_privatekey(SSL_CTX *ctx, const char *file) {
BIO *bio;
RSA *rsa;
bio = BIO_new_file(file, "r");
if (!bio) {
ERR_print_errors_fp(stderr);
return NULL;
}
rsa = PEM_read_bio_RSAPrivateKey(bio, NULL,
ctx->default_passwd_callback, ctx->default_passwd_callback_userdata);
BIO_free(bio);
return rsa;
}
#ifndef OPENSSL_NO_TLSEXT
/*
* Switch the context of the current SSL object to the most appropriate one
* based on the SNI header
*/
int sni_switch_ctx(SSL *ssl, int *al, void *data) {
(void)data;
(void)al;
const char *servername;
const ctx_list *cl;
servername = SSL_get_servername(ssl, TLSEXT_NAMETYPE_host_name);
if (!servername) return SSL_TLSEXT_ERR_NOACK;
// For now, just compare servernames as case insensitive strings. Someday,
// it might be nice to Do The Right Thing around star certs.
for (cl = sni_ctxs; cl != NULL; cl = cl->next) {
if (strcasecmp(servername, cl->servername) == 0) {
SSL_set_SSL_CTX(ssl, cl->ctx);
return SSL_TLSEXT_ERR_NOACK;
}
}
return SSL_TLSEXT_ERR_NOACK;
}
#endif /* OPENSSL_NO_TLSEXT */
/*
* Initialize an SSL context
*/
SSL_CTX *make_ctx(const char *pemfile) {
SSL_CTX *ctx;
RSA *rsa;
long ssloptions = SSL_OP_NO_SSLv2 | SSL_OP_ALL |
SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION;
#ifdef SSL_OP_NO_COMPRESSION
ssloptions |= SSL_OP_NO_COMPRESSION;
#endif
if (CONFIG->ETYPE == ENC_TLS) {
ctx = SSL_CTX_new((CONFIG->PMODE == SSL_CLIENT) ?
TLSv1_client_method() : TLSv1_server_method());
} else if (CONFIG->ETYPE == ENC_SSL) {
ctx = SSL_CTX_new((CONFIG->PMODE == SSL_CLIENT) ?
SSLv23_client_method() : SSLv23_server_method());
} else {
assert(CONFIG->ETYPE == ENC_TLS || CONFIG->ETYPE == ENC_SSL);
return NULL; // Won't happen, but gcc was complaining
}
SSL_CTX_set_options(ctx, ssloptions);
SSL_CTX_set_info_callback(ctx, info_callback);
if (CONFIG->CIPHER_SUITE) {
if (SSL_CTX_set_cipher_list(ctx, CONFIG->CIPHER_SUITE) != 1) {
ERR_print_errors_fp(stderr);
}
}
if (CONFIG->PREFER_SERVER_CIPHERS) {
SSL_CTX_set_options(ctx, SSL_OP_CIPHER_SERVER_PREFERENCE);
}
if (CONFIG->PMODE == SSL_CLIENT) {
return ctx;
}
/* SSL_SERVER Mode stuff */
if (SSL_CTX_use_certificate_chain_file(ctx, pemfile) <= 0) {
ERR_print_errors_fp(stderr);
exit(1);
}
rsa = load_rsa_privatekey(ctx, pemfile);
if (!rsa) {
ERR("Error loading rsa private key\n");
exit(1);
}
if (SSL_CTX_use_RSAPrivateKey(ctx, rsa) <= 0) {
ERR_print_errors_fp(stderr);
exit(1);
}
#ifndef OPENSSL_NO_DH
init_dh(ctx, pemfile);
#endif /* OPENSSL_NO_DH */
#ifndef OPENSSL_NO_TLSEXT
if (!SSL_CTX_set_tlsext_servername_callback(ctx, sni_switch_ctx)) {
ERR("Error setting up SNI support\n");
}
#endif /* OPENSSL_NO_TLSEXT */
#ifdef USE_SHARED_CACHE
if (CONFIG->SHARED_CACHE) {
if (shared_context_init(ctx, CONFIG->SHARED_CACHE) < 0) {
ERR("Unable to alloc memory for shared cache.\n");
exit(1);
}
if (CONFIG->SHCUPD_PORT) {
if (compute_secret(rsa, shared_secret) < 0) {
ERR("Unable to compute shared secret.\n");
exit(1);
}
/* Force tls tickets cause keys differs */
SSL_CTX_set_options(ctx, SSL_OP_NO_TICKET);
if (*shcupd_peers) {
shsess_set_new_cbk(shcupd_session_new);
}
}
}
#endif
RSA_free(rsa);
return ctx;
}
/* Init library and load specified certificate.
* Establishes a SSL_ctx, to act as a template for
* each connection */
void init_openssl() {
SSL_library_init();
SSL_load_error_strings();
assert(CONFIG->CERT_FILES != NULL);
// The first file (i.e., the last file listed in config) is always the
// "default" cert
default_ctx = make_ctx(CONFIG->CERT_FILES->CERT_FILE);
#ifndef OPENSSL_NO_TLSEXT
{
struct cert_files *cf;
int i;
SSL_CTX *ctx;
X509 *x509;
BIO *f;
STACK_OF(GENERAL_NAME) *names = NULL;
GENERAL_NAME *name;
#define PUSH_CTX(asn1_str, ctx) \
do { \
struct ctx_list *cl; \
cl = calloc(1, sizeof(*cl)); \
ASN1_STRING_to_UTF8((unsigned char **)&cl->servername, asn1_str); \
cl->ctx = ctx; \
cl->next = sni_ctxs; \
sni_ctxs = cl; \
} while (0)
// Go through the list of PEMs and make some SSL contexts for them. We also
// keep track of the names associated with each cert so we can do SNI on
// them later
for (cf = CONFIG->CERT_FILES->NEXT; cf != NULL; cf = cf->NEXT) {
ctx = make_ctx(cf->CERT_FILE);
f = BIO_new(BIO_s_file());
// TODO: error checking
if (!BIO_read_filename(f, cf->CERT_FILE)) {
ERR("Could not read cert '%s'\n", cf->CERT_FILE);
}
x509 = PEM_read_bio_X509_AUX(f, NULL, NULL, NULL);
BIO_free(f);
// First, look for Subject Alternative Names
names = X509_get_ext_d2i(x509, NID_subject_alt_name, NULL, NULL);
for (i = 0; i < sk_GENERAL_NAME_num(names); i++) {
name = sk_GENERAL_NAME_value(names, i);
if (name->type == GEN_DNS) {
PUSH_CTX(name->d.dNSName, ctx);
}
}
if (sk_GENERAL_NAME_num(names) > 0) {
sk_GENERAL_NAME_pop_free(names, GENERAL_NAME_free);
// If we actally found some, don't bother looking any further
continue;
} else if (names != NULL) {
sk_GENERAL_NAME_pop_free(names, GENERAL_NAME_free);
}
// Now we're left looking at the CN on the cert
X509_NAME *x509_name = X509_get_subject_name(x509);
i = X509_NAME_get_index_by_NID(x509_name, NID_commonName, -1);
if (i < 0) {
ERR("Could not find Subject Alternative Names or a CN on cert %s\n",
cf->CERT_FILE);
}
X509_NAME_ENTRY *x509_entry = X509_NAME_get_entry(x509_name, i);
PUSH_CTX(x509_entry->value, ctx);
}
}
#undef APPEND_CTX
#endif /* OPENSSL_NO_TLSEXT */
if (CONFIG->ENGINE) {
ENGINE *e = NULL;
ENGINE_load_builtin_engines();
if (!strcmp(CONFIG->ENGINE, "auto"))
ENGINE_register_all_complete();
else {
if ((e = ENGINE_by_id(CONFIG->ENGINE)) == NULL ||
!ENGINE_init(e) ||
!ENGINE_set_default(e, ENGINE_METHOD_ALL)) {
ERR_print_errors_fp(stderr);
exit(1);
}
LOG("{core} will use OpenSSL engine %s.\n", ENGINE_get_id(e));
ENGINE_finish(e);
ENGINE_free(e);
}
}
}
static void prepare_proxy_line(struct sockaddr* ai_addr) {
tcp_proxy_line[0] = 0;
char tcp6_address_string[INET6_ADDRSTRLEN];
if (ai_addr->sa_family == AF_INET) {
struct sockaddr_in* addr = (struct sockaddr_in*)ai_addr;
size_t res = snprintf(tcp_proxy_line,
sizeof(tcp_proxy_line),
"PROXY %%s %%s %s %%hu %hu\r\n",
inet_ntoa(addr->sin_addr),
ntohs(addr->sin_port));
assert(res < sizeof(tcp_proxy_line));
}
else if (ai_addr->sa_family == AF_INET6 ) {
struct sockaddr_in6* addr = (struct sockaddr_in6*)ai_addr;
inet_ntop(AF_INET6,&(addr->sin6_addr),tcp6_address_string,INET6_ADDRSTRLEN);
size_t res = snprintf(tcp_proxy_line,
sizeof(tcp_proxy_line),
"PROXY %%s %%s %s %%hu %hu\r\n",
tcp6_address_string,
ntohs(addr->sin6_port));
assert(res < sizeof(tcp_proxy_line));
}
else {
ERR("The --write-proxy mode is not implemented for this address family.\n");
exit(1);
}
}
/* Create the bound socket in the parent process */
static int create_main_socket() {
struct addrinfo *ai, hints;
memset(&hints, 0, sizeof hints);
hints.ai_family = AF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;
hints.ai_flags = AI_PASSIVE | AI_ADDRCONFIG;
const int gai_err = getaddrinfo(CONFIG->FRONT_IP, CONFIG->FRONT_PORT,
&hints, &ai);
if (gai_err != 0) {
ERR("{getaddrinfo}: [%s]\n", gai_strerror(gai_err));
exit(1);
}
int s = socket(ai->ai_family, SOCK_STREAM, IPPROTO_TCP);
if (s == -1)
fail("{socket: main}");
int t = 1;
setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &t, sizeof(int));
#ifdef SO_REUSEPORT
setsockopt(s, SOL_SOCKET, SO_REUSEPORT, &t, sizeof(int));
#endif
setnonblocking(s);
if (bind(s, ai->ai_addr, ai->ai_addrlen)) {
fail("{bind-socket}");
}
#ifndef NO_DEFER_ACCEPT
#if TCP_DEFER_ACCEPT
int timeout = 1;
setsockopt(s, IPPROTO_TCP, TCP_DEFER_ACCEPT, &timeout, sizeof(int) );
#endif /* TCP_DEFER_ACCEPT */
#endif
prepare_proxy_line(ai->ai_addr);
freeaddrinfo(ai);
listen(s, CONFIG->BACKLOG);
return s;
}
/* Initiate a clear-text nonblocking connect() to the backend IP on behalf
* of a newly connected upstream (encrypted) client*/
static int create_back_socket() {
int s = socket(backaddr->ai_family, SOCK_STREAM, IPPROTO_TCP);
if (s == -1)
return -1;
int flag = 1;
int ret = setsockopt(s, IPPROTO_TCP, TCP_NODELAY, (char *)&flag, sizeof(flag));
if (ret == -1) {
perror("Couldn't setsockopt to backend (TCP_NODELAY)\n");
}
setnonblocking(s);
return s;
}
/* Only enable a libev ev_io event if the proxied connection still
* has both up and down connected */
static void safe_enable_io(proxystate *ps, ev_io *w) {
if (!ps->want_shutdown)
ev_io_start(loop, w);
}
/* Only enable a libev ev_io event if the proxied connection still
* has both up and down connected */
static void shutdown_proxy(proxystate *ps, SHUTDOWN_REQUESTOR req) {
if (ps->want_shutdown || req == SHUTDOWN_HARD) {
ev_io_stop(loop, &ps->ev_w_ssl);
ev_io_stop(loop, &ps->ev_r_ssl);
ev_io_stop(loop, &ps->ev_w_handshake);
ev_io_stop(loop, &ps->ev_r_handshake);
ev_io_stop(loop, &ps->ev_w_connect);
ev_io_stop(loop, &ps->ev_w_clear);
ev_io_stop(loop, &ps->ev_r_clear);
ev_io_stop(loop, &ps->ev_proxy);
close(ps->fd_up);
close(ps->fd_down);
SSL_set_shutdown(ps->ssl, SSL_SENT_SHUTDOWN);
SSL_free(ps->ssl);
free(ps);
}
else {
ps->want_shutdown = 1;
if (req == SHUTDOWN_CLEAR && ringbuffer_is_empty(&ps->ring_clear2ssl))
shutdown_proxy(ps, SHUTDOWN_HARD);
else if (req == SHUTDOWN_SSL && ringbuffer_is_empty(&ps->ring_ssl2clear))
shutdown_proxy(ps, SHUTDOWN_HARD);
}
}
/* Handle various socket errors */
static void handle_socket_errno(proxystate *ps, int backend) {
if (errno == EAGAIN || errno == EWOULDBLOCK || errno == EINTR)
return;
if (errno == ECONNRESET)
ERR("{%s} Connection reset by peer\n", backend ? "backend" : "client");
else if (errno == ETIMEDOUT)
ERR("{%s} Connection to backend timed out\n", backend ? "backend" : "client");
else if (errno == EPIPE)
ERR("{%s} Broken pipe to backend (EPIPE)\n", backend ? "backend" : "client");
else
perror("{backend} [errno]");
shutdown_proxy(ps, SHUTDOWN_CLEAR);
}
/* Start connect to backend */
static void start_connect(proxystate *ps) {
int t = 1;
t = connect(ps->fd_down, backaddr->ai_addr, backaddr->ai_addrlen);
if (t == 0 || errno == EINPROGRESS || errno == EINTR) {
ev_io_start(loop, &ps->ev_w_connect);
return ;
}
perror("{backend-connect}");
shutdown_proxy(ps, SHUTDOWN_HARD);
}
/* Read some data from the backend when libev says data is available--
* write it into the upstream buffer and make sure the write event is
* enabled for the upstream socket */
static void clear_read(struct ev_loop *loop, ev_io *w, int revents) {
(void) revents;
int t;
proxystate *ps = (proxystate *)w->data;
if (ps->want_shutdown) {
ev_io_stop(loop, &ps->ev_r_clear);
return;
}
int fd = w->fd;
char * buf = ringbuffer_write_ptr(&ps->ring_clear2ssl);
t = recv(fd, buf, RING_DATA_LEN, 0);
if (t > 0) {
ringbuffer_write_append(&ps->ring_clear2ssl, t);
if (ringbuffer_is_full(&ps->ring_clear2ssl))
ev_io_stop(loop, &ps->ev_r_clear);
if (ps->handshaked)
safe_enable_io(ps, &ps->ev_w_ssl);
}
else if (t == 0) {
LOG("{%s} Connection closed\n", fd == ps->fd_down ? "backend" : "client");
shutdown_proxy(ps, SHUTDOWN_CLEAR);
}
else {
assert(t == -1);
handle_socket_errno(ps, fd == ps->fd_down ? 1 : 0);
}
}
/* Write some data, previously received on the secure upstream socket,
* out of the downstream buffer and onto the backend socket */
static void clear_write(struct ev_loop *loop, ev_io *w, int revents) {
(void) revents;
int t;
proxystate *ps = (proxystate *)w->data;
int fd = w->fd;
int sz;
assert(!ringbuffer_is_empty(&ps->ring_ssl2clear));
char *next = ringbuffer_read_next(&ps->ring_ssl2clear, &sz);
t = send(fd, next, sz, MSG_NOSIGNAL);
if (t > 0) {
if (t == sz) {
ringbuffer_read_pop(&ps->ring_ssl2clear);
if (ps->handshaked)
safe_enable_io(ps, &ps->ev_r_ssl);
if (ringbuffer_is_empty(&ps->ring_ssl2clear)) {
if (ps->want_shutdown) {
shutdown_proxy(ps, SHUTDOWN_HARD);
return; // dealloc'd
}
ev_io_stop(loop, &ps->ev_w_clear);
}
}
else {
ringbuffer_read_skip(&ps->ring_ssl2clear, t);
}
}
else {
assert(t == -1);
handle_socket_errno(ps, fd == ps->fd_down ? 1 : 0);
}
}