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sbuf.c
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sbuf.c
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/*
* PgBouncer - Lightweight connection pooler for PostgreSQL.
*
* Copyright (c) 2007-2009 Marko Kreen, Skype Technologies OÜ
*
* Permission to use, copy, modify, and/or 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.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
/*
* Stream buffer
*
* The task is to copy data from one socket to another
* efficiently, while allowing callbacks to look
* at packet headers.
*/
#include "bouncer.h"
#ifdef USUAL_LIBSSL_FOR_TLS
#define USE_TLS
#endif
/* sbuf_main_loop() skip_recv values */
#define DO_RECV false
#define SKIP_RECV true
#define ACT_UNSET 0
#define ACT_SEND 1
#define ACT_SKIP 2
#define ACT_CALL 3
enum TLSState {
SBUF_TLS_NONE,
SBUF_TLS_DO_HANDSHAKE,
SBUF_TLS_IN_HANDSHAKE,
SBUF_TLS_OK,
};
enum WaitType {
W_NONE = 0,
W_CONNECT,
W_RECV,
W_SEND,
W_ONCE
};
#define AssertSanity(sbuf) do { \
Assert(iobuf_sane((sbuf)->io)); \
} while (0)
#define AssertActive(sbuf) do { \
Assert((sbuf)->sock > 0); \
AssertSanity(sbuf); \
} while (0)
/* declare static stuff */
static bool sbuf_queue_send(SBuf *sbuf) _MUSTCHECK;
static bool sbuf_send_pending(SBuf *sbuf) _MUSTCHECK;
static bool sbuf_process_pending(SBuf *sbuf) _MUSTCHECK;
static void sbuf_connect_cb(int sock, short flags, void *arg);
static void sbuf_recv_cb(int sock, short flags, void *arg);
static void sbuf_send_cb(int sock, short flags, void *arg);
static void sbuf_try_resync(SBuf *sbuf, bool release);
static bool sbuf_wait_for_data(SBuf *sbuf) _MUSTCHECK;
static void sbuf_main_loop(SBuf *sbuf, bool skip_recv);
static bool sbuf_call_proto(SBuf *sbuf, int event) /* _MUSTCHECK */;
static bool sbuf_actual_recv(SBuf *sbuf, unsigned len) _MUSTCHECK;
static bool sbuf_after_connect_check(SBuf *sbuf) _MUSTCHECK;
static bool handle_tls_handshake(SBuf *sbuf) /* _MUSTCHECK */;
static inline IOBuf *get_iobuf(SBuf *sbuf) { return sbuf->io; }
/* regular I/O */
static int raw_sbufio_recv(struct SBuf *sbuf, void *dst, unsigned int len);
static int raw_sbufio_send(struct SBuf *sbuf, const void *data, unsigned int len);
static int raw_sbufio_close(struct SBuf *sbuf);
static const SBufIO raw_sbufio_ops = {
raw_sbufio_recv,
raw_sbufio_send,
raw_sbufio_close
};
/* I/O over TLS */
#ifdef USE_TLS
static int tls_sbufio_recv(struct SBuf *sbuf, void *dst, unsigned int len);
static int tls_sbufio_send(struct SBuf *sbuf, const void *data, unsigned int len);
static int tls_sbufio_close(struct SBuf *sbuf);
static const SBufIO tls_sbufio_ops = {
tls_sbufio_recv,
tls_sbufio_send,
tls_sbufio_close
};
static void sbuf_tls_handshake_cb(int fd, short flags, void *_sbuf);
#endif
/*********************************
* Public functions
*********************************/
/* initialize SBuf with proto handler */
void sbuf_init(SBuf *sbuf, sbuf_cb_t proto_fn)
{
memset(sbuf, 0, sizeof(SBuf));
sbuf->proto_cb = proto_fn;
sbuf->ops = &raw_sbufio_ops;
}
/* got new socket from accept() */
bool sbuf_accept(SBuf *sbuf, int sock, bool is_unix)
{
bool res;
Assert(iobuf_empty(sbuf->io) && sbuf->sock == 0);
AssertSanity(sbuf);
sbuf->sock = sock;
if (!tune_socket(sock, is_unix))
goto failed;
if (!cf_reboot) {
res = sbuf_wait_for_data(sbuf);
if (!res)
goto failed;
/* socket should already have some data (linux only) */
if (cf_tcp_defer_accept && !is_unix) {
sbuf_main_loop(sbuf, DO_RECV);
if (!sbuf->sock)
return false;
}
}
return true;
failed:
sbuf_call_proto(sbuf, SBUF_EV_RECV_FAILED);
return false;
}
/* need to connect() to get a socket */
bool sbuf_connect(SBuf *sbuf, const struct sockaddr *sa, int sa_len, int timeout_sec)
{
int res, sock;
struct timeval timeout;
bool is_unix = sa->sa_family == AF_UNIX;
Assert(iobuf_empty(sbuf->io) && sbuf->sock == 0);
AssertSanity(sbuf);
/*
* common stuff
*/
sock = socket(sa->sa_family, SOCK_STREAM, 0);
if (sock < 0) {
/* probably fd limit */
goto failed;
}
if (!tune_socket(sock, is_unix))
goto failed;
sbuf->sock = sock;
timeout.tv_sec = timeout_sec;
timeout.tv_usec = 0;
/* launch connection */
res = safe_connect(sock, sa, sa_len);
if (res == 0) {
/* unix socket gives connection immediately */
sbuf_connect_cb(sock, EV_WRITE, sbuf);
return true;
} else if (errno == EINPROGRESS) {
/* tcp socket needs waiting */
event_set(&sbuf->ev, sock, EV_WRITE, sbuf_connect_cb, sbuf);
res = event_add(&sbuf->ev, &timeout);
if (res >= 0) {
sbuf->wait_type = W_CONNECT;
return true;
}
}
failed:
log_warning("sbuf_connect failed: %s", strerror(errno));
if (sock >= 0)
safe_close(sock);
sbuf->sock = 0;
sbuf_call_proto(sbuf, SBUF_EV_CONNECT_FAILED);
return false;
}
/* don't wait for data on this socket */
bool sbuf_pause(SBuf *sbuf)
{
AssertActive(sbuf);
Assert(sbuf->wait_type == W_RECV);
if (event_del(&sbuf->ev) < 0) {
log_warning("event_del: %s", strerror(errno));
return false;
}
sbuf->wait_type = W_NONE;
return true;
}
/* resume from pause, start waiting for data */
void sbuf_continue(SBuf *sbuf)
{
bool do_recv = DO_RECV;
bool res;
AssertActive(sbuf);
res = sbuf_wait_for_data(sbuf);
if (!res) {
/* drop if problems */
sbuf_call_proto(sbuf, SBUF_EV_RECV_FAILED);
return;
}
/*
* It's tempting to try to avoid the recv() but that would
* only work if no code wants to see full packet.
*
* This is not true in ServerParameter case.
*/
/*
* if (sbuf->recv_pos - sbuf->pkt_pos >= SBUF_SMALL_PKT)
* do_recv = false;
*/
sbuf_main_loop(sbuf, do_recv);
}
/*
* Resume from pause and give socket over to external
* callback function.
*
* The callback will be called with arg given to sbuf_init.
*/
bool sbuf_continue_with_callback(SBuf *sbuf, sbuf_libevent_cb user_cb)
{
int err;
AssertActive(sbuf);
event_set(&sbuf->ev, sbuf->sock, EV_READ | EV_PERSIST,
user_cb, sbuf);
err = event_add(&sbuf->ev, NULL);
if (err < 0) {
log_warning("sbuf_continue_with_callback: %s", strerror(errno));
return false;
}
sbuf->wait_type = W_RECV;
return true;
}
bool sbuf_use_callback_once(SBuf *sbuf, short ev, sbuf_libevent_cb user_cb)
{
int err;
AssertActive(sbuf);
if (sbuf->wait_type != W_NONE) {
err = event_del(&sbuf->ev);
sbuf->wait_type = W_NONE; /* make sure its called only once */
if (err < 0) {
log_warning("sbuf_queue_once: event_del failed: %s", strerror(errno));
return false;
}
}
/* setup one one-off event handler */
event_set(&sbuf->ev, sbuf->sock, ev, user_cb, sbuf);
err = event_add(&sbuf->ev, NULL);
if (err < 0) {
log_warning("sbuf_queue_once: event_add failed: %s", strerror(errno));
return false;
}
sbuf->wait_type = W_ONCE;
return true;
}
/* socket cleanup & close: keeps .handler and .arg values */
bool sbuf_close(SBuf *sbuf)
{
if (sbuf->wait_type) {
Assert(sbuf->sock);
/* event_del() acts funny occasionally, debug it */
errno = 0;
if (event_del(&sbuf->ev) < 0) {
if (errno) {
log_warning("event_del: %s", strerror(errno));
} else {
log_warning("event_del: libevent error");
}
/* we can retry whole sbuf_close() if needed */
/* if (errno == ENOMEM) return false; */
}
}
sbuf_op_close(sbuf);
sbuf->dst = NULL;
sbuf->sock = 0;
sbuf->pkt_remain = 0;
sbuf->pkt_action = sbuf->wait_type = 0;
if (sbuf->io) {
slab_free(iobuf_cache, sbuf->io);
sbuf->io = NULL;
}
return true;
}
/* proto_fn tells to send some bytes to socket */
void sbuf_prepare_send(SBuf *sbuf, SBuf *dst, unsigned amount)
{
AssertActive(sbuf);
Assert(sbuf->pkt_remain == 0);
/* Assert(sbuf->pkt_action == ACT_UNSET || sbuf->pkt_action == ACT_SEND || iobuf_amount_pending(&sbuf->io)); */
Assert(amount > 0);
sbuf->pkt_action = ACT_SEND;
sbuf->pkt_remain = amount;
sbuf->dst = dst;
}
/* proto_fn tells to skip some amount of bytes */
void sbuf_prepare_skip(SBuf *sbuf, unsigned amount)
{
AssertActive(sbuf);
Assert(sbuf->pkt_remain == 0);
/* Assert(sbuf->pkt_action == ACT_UNSET || iobuf_send_pending_avail(&sbuf->io)); */
Assert(amount > 0);
sbuf->pkt_action = ACT_SKIP;
sbuf->pkt_remain = amount;
}
/* proto_fn tells to skip some amount of bytes */
void sbuf_prepare_fetch(SBuf *sbuf, unsigned amount)
{
AssertActive(sbuf);
Assert(sbuf->pkt_remain == 0);
/* Assert(sbuf->pkt_action == ACT_UNSET || iobuf_send_pending_avail(&sbuf->io)); */
Assert(amount > 0);
sbuf->pkt_action = ACT_CALL;
sbuf->pkt_remain = amount;
/* sbuf->dst = NULL; // FIXME ?? */
}
/*************************
* Internal functions
*************************/
/*
* Call proto callback with proper struct MBuf.
*
* If callback returns true it used one of sbuf_prepare_* on sbuf,
* and processing can continue.
*
* If it returned false it used sbuf_pause(), sbuf_close() or simply
* wants to wait for next event loop (e.g. too few data available).
* Callee should not touch sbuf in that case and just return to libevent.
*/
static bool sbuf_call_proto(SBuf *sbuf, int event)
{
struct MBuf mbuf;
IOBuf *io = sbuf->io;
bool res;
AssertSanity(sbuf);
Assert(event != SBUF_EV_READ || iobuf_amount_parse(io) > 0);
/* if pkt callback, limit only with current packet */
if (event == SBUF_EV_PKT_CALLBACK) {
iobuf_parse_limit(io, &mbuf, sbuf->pkt_remain);
} else if (event == SBUF_EV_READ) {
iobuf_parse_all(io, &mbuf);
} else {
memset(&mbuf, 0, sizeof(mbuf));
}
res = sbuf->proto_cb(sbuf, event, &mbuf);
AssertSanity(sbuf);
Assert(event != SBUF_EV_READ || !res || sbuf->sock > 0);
return res;
}
/* let's wait for new data */
static bool sbuf_wait_for_data(SBuf *sbuf)
{
int err;
event_set(&sbuf->ev, sbuf->sock, EV_READ | EV_PERSIST, sbuf_recv_cb, sbuf);
err = event_add(&sbuf->ev, NULL);
if (err < 0) {
log_warning("sbuf_wait_for_data: event_add failed: %s", strerror(errno));
return false;
}
sbuf->wait_type = W_RECV;
return true;
}
static void sbuf_recv_forced_cb(int sock, short flags, void *arg)
{
SBuf *sbuf = arg;
sbuf->wait_type = W_NONE;
if (sbuf_wait_for_data(sbuf)) {
sbuf_recv_cb(sock, flags, arg);
} else {
sbuf_call_proto(sbuf, SBUF_EV_RECV_FAILED);
}
}
static bool sbuf_wait_for_data_forced(SBuf *sbuf)
{
int err;
struct timeval tv_min;
tv_min.tv_sec = 0;
tv_min.tv_usec = 1;
if (sbuf->wait_type != W_NONE) {
event_del(&sbuf->ev);
sbuf->wait_type = W_NONE;
}
event_set(&sbuf->ev, sbuf->sock, EV_READ, sbuf_recv_forced_cb, sbuf);
err = event_add(&sbuf->ev, &tv_min);
if (err < 0) {
log_warning("sbuf_wait_for_data: event_add failed: %s", strerror(errno));
return false;
}
sbuf->wait_type = W_ONCE;
return true;
}
/* libevent EV_WRITE: called when dest socket is writable again */
static void sbuf_send_cb(int sock, short flags, void *arg)
{
SBuf *sbuf = arg;
bool res;
/* sbuf was closed before in this loop */
if (!sbuf->sock)
return;
AssertSanity(sbuf);
Assert(sbuf->wait_type == W_SEND);
sbuf->wait_type = W_NONE;
/* prepare normal situation for sbuf_main_loop */
res = sbuf_wait_for_data(sbuf);
if (res) {
/* here we should certainly skip recv() */
sbuf_main_loop(sbuf, SKIP_RECV);
} else {
/* drop if problems */
sbuf_call_proto(sbuf, SBUF_EV_SEND_FAILED);
}
}
/* socket is full, wait until it's writable again */
static bool sbuf_queue_send(SBuf *sbuf)
{
int err;
AssertActive(sbuf);
Assert(sbuf->wait_type == W_RECV);
/* if false is returned, the socket will be closed later */
/* stop waiting for read events */
err = event_del(&sbuf->ev);
sbuf->wait_type = W_NONE; /* make sure its called only once */
if (err < 0) {
log_warning("sbuf_queue_send: event_del failed: %s", strerror(errno));
return false;
}
/* instead wait for EV_WRITE on destination socket */
event_set(&sbuf->ev, sbuf->dst->sock, EV_WRITE, sbuf_send_cb, sbuf);
err = event_add(&sbuf->ev, NULL);
if (err < 0) {
log_warning("sbuf_queue_send: event_add failed: %s", strerror(errno));
return false;
}
sbuf->wait_type = W_SEND;
return true;
}
/*
* There's data in buffer to be sent. Returns bool if processing can continue.
*
* Does not look at pkt_pos/remain fields, expects them to be merged to send_*
*/
static bool sbuf_send_pending(SBuf *sbuf)
{
int res, avail;
IOBuf *io = sbuf->io;
AssertActive(sbuf);
Assert(sbuf->dst || iobuf_amount_pending(io) == 0);
try_more:
/* how much data is available for sending */
avail = iobuf_amount_pending(io);
if (avail == 0)
return true;
if (sbuf->dst->sock == 0) {
log_error("sbuf_send_pending: no dst sock?");
return false;
}
/* actually send it */
//res = iobuf_send_pending(io, sbuf->dst->sock);
res = sbuf_op_send(sbuf->dst, io->buf + io->done_pos, avail);
if (res > 0) {
io->done_pos += res;
} else if (res < 0) {
if (errno == EAGAIN) {
if (!sbuf_queue_send(sbuf))
/* drop if queue failed */
sbuf_call_proto(sbuf, SBUF_EV_SEND_FAILED);
} else {
sbuf_call_proto(sbuf, SBUF_EV_SEND_FAILED);
}
return false;
}
AssertActive(sbuf);
/*
* Should do sbuf_queue_send() immediately?
*
* To be sure, let's run into EAGAIN.
*/
goto try_more;
}
/* process as much data as possible */
static bool sbuf_process_pending(SBuf *sbuf)
{
unsigned avail;
IOBuf *io = sbuf->io;
bool full = iobuf_amount_recv(io) <= 0;
bool res;
while (1) {
AssertActive(sbuf);
/*
* Enough for now?
*
* The (avail <= SBUF_SMALL_PKT) check is to avoid partial pkts.
* As SBuf should not assume knowledge about packets,
* the check is not done in !full case. Packet handler can
* then still notify about partial packet by returning false.
*/
avail = iobuf_amount_parse(io);
if (avail == 0 || (full && avail <= SBUF_SMALL_PKT))
break;
/*
* If start of packet, process packet header.
*/
if (sbuf->pkt_remain == 0) {
res = sbuf_call_proto(sbuf, SBUF_EV_READ);
if (!res)
return false;
Assert(sbuf->pkt_remain > 0);
}
if (sbuf->pkt_action == ACT_SKIP || sbuf->pkt_action == ACT_CALL) {
/* send any pending data before skipping */
if (iobuf_amount_pending(io) > 0) {
res = sbuf_send_pending(sbuf);
if (!res)
return res;
}
}
if (avail > sbuf->pkt_remain)
avail = sbuf->pkt_remain;
switch (sbuf->pkt_action) {
case ACT_SEND:
iobuf_tag_send(io, avail);
break;
case ACT_CALL:
res = sbuf_call_proto(sbuf, SBUF_EV_PKT_CALLBACK);
if (!res)
return false;
/* after callback, skip pkt */
case ACT_SKIP:
iobuf_tag_skip(io, avail);
break;
}
sbuf->pkt_remain -= avail;
}
return sbuf_send_pending(sbuf);
}
/* reposition at buffer start again */
static void sbuf_try_resync(SBuf *sbuf, bool release)
{
IOBuf *io = sbuf->io;
if (io) {
log_noise("resync: done=%d, parse=%d, recv=%d",
io->done_pos, io->parse_pos, io->recv_pos);
}
AssertActive(sbuf);
if (!io)
return;
if (release && iobuf_empty(io)) {
slab_free(iobuf_cache, io);
sbuf->io = NULL;
} else {
iobuf_try_resync(io, SBUF_SMALL_PKT);
}
}
/* actually ask kernel for more data */
static bool sbuf_actual_recv(SBuf *sbuf, unsigned len)
{
int got;
IOBuf *io = sbuf->io;
uint8_t *dst = io->buf + io->recv_pos;
unsigned avail = iobuf_amount_recv(io);
if (len > avail)
len = avail;
got = sbuf_op_recv(sbuf, dst, len);
if (got > 0) {
io->recv_pos += got;
} else if (got == 0) {
/* eof from socket */
sbuf_call_proto(sbuf, SBUF_EV_RECV_FAILED);
return false;
} else if (got < 0 && errno != EAGAIN) {
/* some error occurred */
sbuf_call_proto(sbuf, SBUF_EV_RECV_FAILED);
return false;
}
return true;
}
/* callback for libevent EV_READ */
static void sbuf_recv_cb(int sock, short flags, void *arg)
{
SBuf *sbuf = arg;
sbuf_main_loop(sbuf, DO_RECV);
}
static bool allocate_iobuf(SBuf *sbuf)
{
if (sbuf->io == NULL) {
sbuf->io = slab_alloc(iobuf_cache);
if (sbuf->io == NULL) {
sbuf_call_proto(sbuf, SBUF_EV_RECV_FAILED);
return false;
}
iobuf_reset(sbuf->io);
}
return true;
}
/*
* Main recv-parse-send-repeat loop.
*
* Reason for skip_recv is to avoid extra recv(). The problem with it
* is EOF from socket. Currently that means that the pending data is
* dropped. Fortunately server sockets are not paused and dropping
* data from client is no problem. So only place where skip_recv is
* important is sbuf_send_cb().
*/
static void sbuf_main_loop(SBuf *sbuf, bool skip_recv)
{
unsigned free, ok;
int loopcnt = 0;
/* sbuf was closed before in this event loop */
if (!sbuf->sock)
return;
/* reading should be disabled when waiting */
Assert(sbuf->wait_type == W_RECV);
AssertSanity(sbuf);
if (!allocate_iobuf(sbuf))
return;
/* avoid recv() if asked */
if (skip_recv)
goto skip_recv;
try_more:
/* make room in buffer */
sbuf_try_resync(sbuf, false);
/* avoid spending too much time on single socket */
if (cf_sbuf_loopcnt > 0 && loopcnt >= cf_sbuf_loopcnt) {
log_debug("loopcnt full");
/*
* sbuf_process_pending() avoids some data if buffer is full,
* but as we exit processing loop here, we need to retry
* after resync to process all data. (result is ignored)
*/
ok = sbuf_process_pending(sbuf);
sbuf_wait_for_data_forced(sbuf);
return;
}
loopcnt++;
/*
* here used to be if (free > SBUF_SMALL_PKT) check
* but with skip_recv switch its should not be needed anymore.
*/
free = iobuf_amount_recv(sbuf->io);
if (free > 0) {
/*
* When suspending, try to hit packet boundary ASAP.
*/
if (cf_pause_mode == P_SUSPEND
&& sbuf->pkt_remain > 0
&& sbuf->pkt_remain < free)
{
free = sbuf->pkt_remain;
}
/* now fetch the data */
ok = sbuf_actual_recv(sbuf, free);
if (!ok)
return;
}
skip_recv:
/* now handle it */
ok = sbuf_process_pending(sbuf);
if (!ok)
return;
/* if the buffer is full, there can be more data available */
if (iobuf_amount_recv(sbuf->io) <= 0)
goto try_more;
/* clean buffer */
sbuf_try_resync(sbuf, true);
/* notify proto that all is sent */
if (sbuf_is_empty(sbuf))
sbuf_call_proto(sbuf, SBUF_EV_FLUSH);
if (sbuf->tls_state == SBUF_TLS_DO_HANDSHAKE) {
sbuf->pkt_action = SBUF_TLS_IN_HANDSHAKE;
handle_tls_handshake(sbuf);
}
}
/* check if there is any error pending on socket */
static bool sbuf_after_connect_check(SBuf *sbuf)
{
int optval = 0, err;
socklen_t optlen = sizeof(optval);
err = getsockopt(sbuf->sock, SOL_SOCKET, SO_ERROR, (void*)&optval, &optlen);
if (err < 0) {
log_debug("sbuf_after_connect_check: getsockopt: %s",
strerror(errno));
return false;
}
if (optval != 0) {
log_debug("sbuf_after_connect_check: pending error: %s",
strerror(optval));
return false;
}
return true;
}
/* callback for libevent EV_WRITE when connecting */
static void sbuf_connect_cb(int sock, short flags, void *arg)
{
SBuf *sbuf = arg;
Assert(sbuf->wait_type == W_CONNECT || sbuf->wait_type == W_NONE);
sbuf->wait_type = W_NONE;
if (flags & EV_WRITE) {
if (!sbuf_after_connect_check(sbuf))
goto failed;
if (!sbuf_call_proto(sbuf, SBUF_EV_CONNECT_OK))
return;
if (!sbuf_wait_for_data(sbuf))
goto failed;
return;
}
failed:
sbuf_call_proto(sbuf, SBUF_EV_CONNECT_FAILED);
}
/* send some data to listening socket */
bool sbuf_answer(SBuf *sbuf, const void *buf, unsigned len)
{
int res;
if (sbuf->sock <= 0)
return false;
res = sbuf_op_send(sbuf, buf, len);
if (res < 0) {
log_debug("sbuf_answer: error sending: %s", strerror(errno));
} else if ((unsigned)res != len) {
log_debug("sbuf_answer: partial send: len=%d sent=%d", len, res);
}
return (unsigned)res == len;
}
/*
* Standard IO ops.
*/
static int raw_sbufio_recv(struct SBuf *sbuf, void *dst, unsigned int len)
{
return safe_recv(sbuf->sock, dst, len, 0);
}
static int raw_sbufio_send(struct SBuf *sbuf, const void *data, unsigned int len)
{
return safe_send(sbuf->sock, data, len, 0);
}
static int raw_sbufio_close(struct SBuf *sbuf)
{
if (sbuf->sock > 0) {
safe_close(sbuf->sock);
sbuf->sock = 0;
}
return 0;
}
/*
* TLS support.
*/
#ifdef USE_TLS
static struct tls_config *client_accept_conf;
static struct tls_config *server_connect_conf;
static struct tls *client_accept_base;
/*
* TLS setup
*/
static void setup_tls(struct tls_config *conf, const char *pfx, int sslmode,
const char *protocols, const char *ciphers,
const char *keyfile, const char *certfile, const char *cafile,
const char *dheparams, const char *ecdhecurve,
bool does_connect)
{
int err;
if (*protocols) {
uint32_t protos = TLS_PROTOCOLS_ALL;
err = tls_config_parse_protocols(&protos, protocols);
if (err) {
log_error("Invalid %s_protocols: %s", pfx, protocols);
} else {
tls_config_set_protocols(conf, protos);
}
}
if (*ciphers) {
err = tls_config_set_ciphers(conf, ciphers);
if (err)
log_error("Invalid %s_ciphers: %s", pfx, ciphers);
}
if (*dheparams) {
err = tls_config_set_dheparams(conf, dheparams);
if (err)
log_error("Invalid %s_dheparams: %s", pfx, dheparams);
}
if (*ecdhecurve) {
err = tls_config_set_ecdhecurve(conf, ecdhecurve);
if (err)
log_error("Invalid %s_ecdhecurve: %s", pfx, ecdhecurve);
}
if (*cafile) {
err = tls_config_set_ca_file(conf, cafile);
if (err)
log_error("Invalid %s_ca_file: %s", pfx, cafile);
}
if (*keyfile) {
err = tls_config_set_key_file(conf, keyfile);
if (err)
log_error("Invalid %s_key_file: %s", pfx, keyfile);
}
if (*certfile) {
err = tls_config_set_cert_file(conf, certfile);
if (err)
log_error("Invalid %s_cert_file: %s", pfx, certfile);
}
if (does_connect) {
/* TLS client, check server? */
if (sslmode == SSLMODE_VERIFY_FULL) {
tls_config_verify(conf);
} else if (sslmode == SSLMODE_VERIFY_CA) {
tls_config_verify(conf);
tls_config_insecure_noverifyname(conf);
} else {
tls_config_insecure_noverifycert(conf);
tls_config_insecure_noverifyname(conf);
}
} else {
/* TLS server, check client? */
if (sslmode == SSLMODE_VERIFY_FULL) {
tls_config_verify_client(conf);
} else if (sslmode == SSLMODE_VERIFY_CA) {
tls_config_verify_client(conf);
} else {
tls_config_verify_client_optional(conf);
}
}
}
void sbuf_tls_setup(void)
{
int err;
if (cf_client_tls_sslmode != SSLMODE_DISABLED) {
if (!*cf_client_tls_key_file || !*cf_client_tls_cert_file)
die("To allow TLS connections from clients, client_tls_key_file and client_tls_cert_file must be set.");
}
if (cf_auth_type == AUTH_CERT) {
if (cf_client_tls_sslmode != SSLMODE_VERIFY_FULL)
die("auth_type=cert requires client_tls_sslmode=SSLMODE_VERIFY_FULL");
if (*cf_client_tls_ca_file == '\0')
die("auth_type=cert requires client_tls_ca_file");
} else if (cf_client_tls_sslmode > SSLMODE_VERIFY_CA && *cf_client_tls_ca_file == '\0') {
die("client_tls_sslmode requires client_tls_ca_file");
}
err = tls_init();
if (err)
fatal("tls_init failed");
if (cf_server_tls_sslmode != SSLMODE_DISABLED) {
server_connect_conf = tls_config_new();
if (!server_connect_conf)
die("tls_config_new failed 1");
setup_tls(server_connect_conf, "server_tls", cf_server_tls_sslmode,
cf_server_tls_protocols, cf_server_tls_ciphers,
cf_server_tls_key_file, cf_server_tls_cert_file,
cf_server_tls_ca_file, "", "", true);
}
if (cf_client_tls_sslmode != SSLMODE_DISABLED) {
client_accept_conf = tls_config_new();
if (!client_accept_conf)
die("tls_config_new failed 2");
setup_tls(client_accept_conf, "client_tls", cf_client_tls_sslmode,
cf_client_tls_protocols, cf_client_tls_ciphers,
cf_client_tls_key_file, cf_client_tls_cert_file,
cf_client_tls_ca_file, cf_client_tls_dheparams,
cf_client_tls_ecdhecurve, false);
client_accept_base = tls_server();
if (!client_accept_base)
die("server_base failed");
err = tls_configure(client_accept_base, client_accept_conf);
if (err)
die("TLS setup failed: %s", tls_error(client_accept_base));
}
}
/*
* TLS handshake
*/
static bool handle_tls_handshake(SBuf *sbuf)
{
int err;
err = tls_handshake(sbuf->tls);
log_noise("tls_handshake: err=%d", err);
if (err == TLS_WANT_POLLIN) {
return sbuf_use_callback_once(sbuf, EV_READ, sbuf_tls_handshake_cb);