construct/ircd/sslproc.c

/*
 *  sslproc.c: An interface to ssld
 *  Copyright (C) 2007 Aaron Sethman <androsyn@ratbox.org>
 *  Copyright (C) 2007 ircd-ratbox development team
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301
 *  USA
 */

#include <rb_lib.h>
#include "stdinc.h"


#include "s_conf.h"
#include "logger.h"
#include "listener.h"
#include "sslproc.h"
#include "s_serv.h"
#include "ircd.h"
#include "hash.h"
#include "client.h"
#include "send.h"
#include "packet.h"

#define ZIPSTATS_TIME           60

static void collect_zipstats(void *unused);
static void ssl_read_ctl(rb_fde_t * F, void *data);
static int ssld_count;

static char tmpbuf[READBUF_SIZE];
static char nul = '\0';

#define MAXPASSFD 4
#define READSIZE 1024
typedef struct _ssl_ctl_buf
{
	rb_dlink_node node;
	char *buf;
	size_t buflen;
	rb_fde_t *F[MAXPASSFD];
	int nfds;
} ssl_ctl_buf_t;


struct _ssl_ctl
{
	rb_dlink_node node;
	int cli_count;
	rb_fde_t *F;
	rb_fde_t *P;
	pid_t pid;
	rb_dlink_list readq;
	rb_dlink_list writeq;
	uint8_t shutdown;
	uint8_t dead;
	char version[256];
};

static void send_new_ssl_certs_one(ssl_ctl_t * ctl, const char *ssl_cert,
				   const char *ssl_private_key, const char *ssl_dh_params,
				   const char *ssl_cipher_list);
static void send_init_prng(ssl_ctl_t * ctl, prng_seed_t seedtype, const char *path);
static void send_certfp_method(ssl_ctl_t *ctl, int method);


static rb_dlink_list ssl_daemons;

static inline uint32_t
buf_to_uint32(char *buf)
{
	uint32_t x;
	memcpy(&x, buf, sizeof(x));
	return x;
}

static inline void
uint32_to_buf(char *buf, uint32_t x)
{
	memcpy(buf, &x, sizeof(x));
	return;
}

static ssl_ctl_t *
allocate_ssl_daemon(rb_fde_t * F, rb_fde_t * P, int pid)
{
	ssl_ctl_t *ctl;

	if(F == NULL || pid < 0)
		return NULL;
	ctl = rb_malloc(sizeof(ssl_ctl_t));
	ctl->F = F;
	ctl->P = P;
	ctl->pid = pid;
	ssld_count++;
	rb_dlinkAdd(ctl, &ctl->node, &ssl_daemons);
	return ctl;
}

static void
free_ssl_daemon(ssl_ctl_t * ctl)
{
	rb_dlink_node *ptr;
	ssl_ctl_buf_t *ctl_buf;
	int x;
	if(ctl->cli_count)
		return;

	RB_DLINK_FOREACH(ptr, ctl->readq.head)
	{
		ctl_buf = ptr->data;
		for(x = 0; x < ctl_buf->nfds; x++)
			rb_close(ctl_buf->F[x]);

		rb_free(ctl_buf->buf);
		rb_free(ctl_buf);
	}

	RB_DLINK_FOREACH(ptr, ctl->writeq.head)
	{
		ctl_buf = ptr->data;
		for(x = 0; x < ctl_buf->nfds; x++)
			rb_close(ctl_buf->F[x]);

		rb_free(ctl_buf->buf);
		rb_free(ctl_buf);
	}
	rb_close(ctl->F);
	rb_close(ctl->P);
	rb_dlinkDelete(&ctl->node, &ssl_daemons);
	rb_free(ctl);
}

static char *ssld_path;

static int ssld_spin_count = 0;
static time_t last_spin;
static int ssld_wait = 0;


void
restart_ssld(void)
{
	rb_dlink_node *ptr, *next;
	ssl_ctl_t *ctl;

	RB_DLINK_FOREACH_SAFE(ptr, next, ssl_daemons.head)
	{
		ctl = ptr->data;
		if(ctl->dead)
			continue;
		if(ctl->shutdown)
			continue;
		ctl->shutdown = 1;
		ssld_count--;
		if(!ctl->cli_count)
		{
			rb_kill(ctl->pid, SIGKILL);
			free_ssl_daemon(ctl);
		}
	}

	start_ssldaemon(ServerInfo.ssld_count, ServerInfo.ssl_cert, ServerInfo.ssl_private_key, ServerInfo.ssl_dh_params, ServerInfo.ssl_cipher_list);
}

static void
ssl_killall(void)
{
	rb_dlink_node *ptr, *next;
	ssl_ctl_t *ctl;
	RB_DLINK_FOREACH_SAFE(ptr, next, ssl_daemons.head)
	{
		ctl = ptr->data;
		if(ctl->dead)
			continue;
		ctl->dead = 1;
		if(!ctl->shutdown)
			ssld_count--;
		rb_kill(ctl->pid, SIGKILL);
		if(!ctl->cli_count)
			free_ssl_daemon(ctl);
	}
}

static void
ssl_dead(ssl_ctl_t * ctl)
{
	if(ctl->dead)
		return;

	ctl->dead = 1;
	rb_kill(ctl->pid, SIGKILL);	/* make sure the process is really gone */

	if(!ctl->shutdown)
	{
		ssld_count--;
		ilog(L_MAIN, "ssld helper died - attempting to restart");
		sendto_realops_snomask(SNO_GENERAL, L_ALL, "ssld helper died - attempting to restart");
		start_ssldaemon(1, ServerInfo.ssl_cert, ServerInfo.ssl_private_key, ServerInfo.ssl_dh_params, ServerInfo.ssl_cipher_list);
	}
}

static void
ssl_do_pipe(rb_fde_t * F, void *data)
{
	int retlen;
	ssl_ctl_t *ctl = data;
	retlen = rb_write(F, "0", 1);
	if(retlen == 0 || (retlen < 0 && !rb_ignore_errno(errno)))
	{
		ssl_dead(ctl);
		return;
	}
	rb_setselect(F, RB_SELECT_READ, ssl_do_pipe, data);
}

static void
restart_ssld_event(void *unused)
{
	ssld_spin_count = 0;
	last_spin = 0;
	ssld_wait = 0;
	if(ServerInfo.ssld_count > get_ssld_count())
	{
		int start = ServerInfo.ssld_count - get_ssld_count();
		ilog(L_MAIN, "Attempting to restart ssld processes");
		sendto_realops_snomask(SNO_GENERAL, L_ALL, "Attempt to restart ssld processes");
		start_ssldaemon(start, ServerInfo.ssl_cert, ServerInfo.ssl_private_key, ServerInfo.ssl_dh_params, ServerInfo.ssl_cipher_list);
	}
}

int
start_ssldaemon(int count, const char *ssl_cert, const char *ssl_private_key, const char *ssl_dh_params, const char *ssl_cipher_list)
{
	rb_fde_t *F1, *F2;
	rb_fde_t *P1, *P2;
#ifdef _WIN32
	const char *suffix = ".exe";
#else
	const char *suffix = "";
#endif

	char fullpath[PATH_MAX + 1];
	char fdarg[6];
	const char *parv[2];
	char buf[128];
	char s_pid[10];
	pid_t pid;
	int started = 0, i;

	if(ssld_wait)
		return 0;

	if(ssld_spin_count > 20 && (rb_current_time() - last_spin < 5))
	{
		ilog(L_MAIN, "ssld helper is spinning - will attempt to restart in 1 minute");
		sendto_realops_snomask(SNO_GENERAL, L_ALL,
				       "ssld helper is spinning - will attempt to restart in 1 minute");
		rb_event_add("restart_ssld_event", restart_ssld_event, NULL, 60);
		ssld_wait = 1;
		return 0;
	}

	ssld_spin_count++;
	last_spin = rb_current_time();

	if(ssld_path == NULL)
	{
		snprintf(fullpath, sizeof(fullpath), "%s/ssld%s", PKGLIBEXECDIR, suffix);

		if(access(fullpath, X_OK) == -1)
		{
			snprintf(fullpath, sizeof(fullpath), "%s/bin/ssld%s",
				    ConfigFileEntry.dpath, suffix);
			if(access(fullpath, X_OK) == -1)
			{
				ilog(L_MAIN,
				     "Unable to execute ssld%s in %s or %s/bin",
				     suffix, PKGLIBEXECDIR, ConfigFileEntry.dpath);
				return 0;
			}
		}
		ssld_path = rb_strdup(fullpath);
	}
	rb_strlcpy(buf, "-ircd ssld daemon", sizeof(buf));
	parv[0] = buf;
	parv[1] = NULL;

	for(i = 0; i < count; i++)
	{
		ssl_ctl_t *ctl;
		if(rb_socketpair(AF_UNIX, SOCK_DGRAM, 0, &F1, &F2, "SSL/TLS handle passing socket") == -1)
		{
			ilog(L_MAIN, "Unable to create ssld - rb_socketpair failed: %s", strerror(errno));
			return started;
		}

		rb_set_buffers(F1, READBUF_SIZE);
		rb_set_buffers(F2, READBUF_SIZE);
		snprintf(fdarg, sizeof(fdarg), "%d", rb_get_fd(F2));
		rb_setenv("CTL_FD", fdarg, 1);
		if(rb_pipe(&P1, &P2, "SSL/TLS pipe") == -1)
		{
			ilog(L_MAIN, "Unable to create ssld - rb_pipe failed: %s", strerror(errno));
			return started;
		}
		snprintf(fdarg, sizeof(fdarg), "%d", rb_get_fd(P1));
		rb_setenv("CTL_PIPE", fdarg, 1);
		snprintf(s_pid, sizeof(s_pid), "%d", (int)getpid());
		rb_setenv("CTL_PPID", s_pid, 1);
#ifdef _WIN32
		SetHandleInformation((HANDLE) rb_get_fd(F2), HANDLE_FLAG_INHERIT, 1);
		SetHandleInformation((HANDLE) rb_get_fd(P1), HANDLE_FLAG_INHERIT, 1);
#endif

		pid = rb_spawn_process(ssld_path, (const char **) parv);
		if(pid == -1)
		{
			ilog(L_MAIN, "Unable to create ssld: %s\n", strerror(errno));
			rb_close(F1);
			rb_close(F2);
			rb_close(P1);
			rb_close(P2);
			return started;
		}
		started++;
		rb_close(F2);
		rb_close(P1);
		ctl = allocate_ssl_daemon(F1, P2, pid);
		if(ircd_ssl_ok)
		{
			send_init_prng(ctl, RB_PRNG_DEFAULT, NULL);
			send_certfp_method(ctl, ConfigFileEntry.certfp_method);

			if(ssl_cert != NULL && ssl_private_key != NULL)
				send_new_ssl_certs_one(ctl, ssl_cert, ssl_private_key,
						       ssl_dh_params != NULL ? ssl_dh_params : "",
						       ssl_cipher_list != NULL ? ssl_cipher_list : "");
		}
		ssl_read_ctl(ctl->F, ctl);
		ssl_do_pipe(P2, ctl);

	}
	return started;
}

static void
ssl_process_zipstats(ssl_ctl_t * ctl, ssl_ctl_buf_t * ctl_buf)
{
	struct Client *server;
	struct ZipStats *zips;
	char *parv[7];
	(void) rb_string_to_array(ctl_buf->buf, parv, 6);
	server = find_server(NULL, parv[1]);
	if(server == NULL || server->localClient == NULL || !IsCapable(server, CAP_ZIP))
		return;
	if(server->localClient->zipstats == NULL)
		server->localClient->zipstats = rb_malloc(sizeof(struct ZipStats));

	zips = server->localClient->zipstats;

	zips->in += strtoull(parv[2], NULL, 10);
	zips->in_wire += strtoull(parv[3], NULL, 10);
	zips->out += strtoull(parv[4], NULL, 10);
	zips->out_wire += strtoull(parv[5], NULL, 10);

	if(zips->in > 0)
		zips->in_ratio = ((double) (zips->in - zips->in_wire) / (double) zips->in) * 100.00;
	else
		zips->in_ratio = 0;

	if(zips->out > 0)
		zips->out_ratio = ((double) (zips->out - zips->out_wire) / (double) zips->out) * 100.00;
	else
		zips->out_ratio = 0;
}

static void
ssl_process_dead_fd(ssl_ctl_t * ctl, ssl_ctl_buf_t * ctl_buf)
{
	struct Client *client_p;
	char reason[256];
	uint32_t fd;

	if(ctl_buf->buflen < 6)
		return;		/* bogus message..drop it.. XXX should warn here */

	fd = buf_to_uint32(&ctl_buf->buf[1]);
	rb_strlcpy(reason, &ctl_buf->buf[5], sizeof(reason));
	client_p = find_cli_connid_hash(fd);
	if(client_p == NULL)
		return;
	if(IsAnyServer(client_p) || IsRegistered(client_p))
	{
		/* read any last moment ERROR, QUIT or the like -- jilles */
		if (!strcmp(reason, "Remote host closed the connection"))
			read_packet(client_p->localClient->F, client_p);
		if (IsAnyDead(client_p))
			return;
	}
	if(IsAnyServer(client_p))
	{
		sendto_realops_snomask(SNO_GENERAL, is_remote_connect(client_p) && !IsServer(client_p) ? L_NETWIDE : L_ALL, "ssld error for %s: %s", client_p->name, reason);
		ilog(L_SERVER, "ssld error for %s: %s", log_client_name(client_p, SHOW_IP), reason);
	}
	exit_client(client_p, client_p, &me, reason);
}


static void
ssl_process_cipher_string(ssl_ctl_t *ctl, ssl_ctl_buf_t *ctl_buf)
{
	struct Client *client_p;
	const char *cstring;
	uint32_t fd;

	if(ctl_buf->buflen < 6)
		return;         /* bogus message..drop it.. XXX should warn here */

	fd = buf_to_uint32(&ctl_buf->buf[1]);
	cstring = (const char *)&ctl_buf->buf[5];

	if(EmptyString(cstring))
		return;

	client_p = find_cli_connid_hash(fd);
	if(client_p != NULL && client_p->localClient != NULL)
	{
		rb_free(client_p->localClient->cipher_string);
		client_p->localClient->cipher_string = rb_strdup(cstring);
	}
}


static void
ssl_process_certfp(ssl_ctl_t * ctl, ssl_ctl_buf_t * ctl_buf)
{
	struct Client *client_p;
	uint32_t fd;
	uint32_t len;
	uint8_t *certfp;
	char *certfp_string;

	if(ctl_buf->buflen > 5 + RB_SSL_CERTFP_LEN)
		return;		/* bogus message..drop it.. XXX should warn here */

	fd = buf_to_uint32(&ctl_buf->buf[1]);
	len = buf_to_uint32(&ctl_buf->buf[5]);
	certfp = (uint8_t *)&ctl_buf->buf[9];
	client_p = find_cli_connid_hash(fd);
	if(client_p == NULL)
		return;
	rb_free(client_p->certfp);
	certfp_string = rb_malloc(len * 2 + 1);
	for(uint32_t i = 0; i < len; i++)
		snprintf(certfp_string + 2 * i, 3, "%02x",
				certfp[i]);
	client_p->certfp = certfp_string;
}

static void
ssl_process_cmd_recv(ssl_ctl_t * ctl)
{
	static const char *cannot_setup_ssl = "ssld cannot setup ssl, check your certificates and private key";
	static const char *no_ssl_or_zlib = "ssld has neither SSL/TLS or zlib support killing all sslds";
	rb_dlink_node *ptr, *next;
	ssl_ctl_buf_t *ctl_buf;
	unsigned long len;

	if(ctl->dead)
		return;

	RB_DLINK_FOREACH_SAFE(ptr, next, ctl->readq.head)
	{
		ctl_buf = ptr->data;
		switch (*ctl_buf->buf)
		{
		case 'N':
			ircd_ssl_ok = false;	/* ssld says it can't do ssl/tls */
			break;
		case 'D':
			ssl_process_dead_fd(ctl, ctl_buf);
			break;
		case 'C':
			ssl_process_cipher_string(ctl, ctl_buf);
			break;
		case 'F':
			ssl_process_certfp(ctl, ctl_buf);
			break;
		case 'S':
			ssl_process_zipstats(ctl, ctl_buf);
			break;
		case 'I':
			ircd_ssl_ok = false;
			ilog(L_MAIN, "%s", cannot_setup_ssl);
			sendto_realops_snomask(SNO_GENERAL, L_ALL, "%s", cannot_setup_ssl);
			break;
		case 'U':
			ircd_zlib_ok = 0;
			ircd_ssl_ok = false;
			ilog(L_MAIN, "%s", no_ssl_or_zlib);
			sendto_realops_snomask(SNO_GENERAL, L_ALL, "%s", no_ssl_or_zlib);
			ssl_killall();
			return;
		case 'V':
			len = ctl_buf->buflen - 1;
			if (len > sizeof(ctl->version) - 1)
				len = sizeof(ctl->version) - 1;
			strncpy(ctl->version, &ctl_buf->buf[1], len);
		case 'z':
			ircd_zlib_ok = 0;
			break;
		default:
			ilog(L_MAIN, "Received invalid command from ssld: %s", ctl_buf->buf);
			sendto_realops_snomask(SNO_GENERAL, L_ALL, "Received invalid command from ssld");
			break;
		}
		rb_dlinkDelete(ptr, &ctl->readq);
		rb_free(ctl_buf->buf);
		rb_free(ctl_buf);
	}

}


static void
ssl_read_ctl(rb_fde_t * F, void *data)
{
	ssl_ctl_buf_t *ctl_buf;
	ssl_ctl_t *ctl = data;
	int retlen;

	if(ctl->dead)
		return;
	do
	{
		ctl_buf = rb_malloc(sizeof(ssl_ctl_buf_t));
		ctl_buf->buf = rb_malloc(READSIZE);
		retlen = rb_recv_fd_buf(ctl->F, ctl_buf->buf, READSIZE, ctl_buf->F, 4);
		ctl_buf->buflen = retlen;
		if(retlen <= 0)
		{
			rb_free(ctl_buf->buf);
			rb_free(ctl_buf);
		}
		else
			rb_dlinkAddTail(ctl_buf, &ctl_buf->node, &ctl->readq);
	}
	while(retlen > 0);

	if(retlen == 0 || (retlen < 0 && !rb_ignore_errno(errno)))
	{
		ssl_dead(ctl);
		return;
	}
	ssl_process_cmd_recv(ctl);
	rb_setselect(ctl->F, RB_SELECT_READ, ssl_read_ctl, ctl);
}

static ssl_ctl_t *
which_ssld(void)
{
	ssl_ctl_t *ctl, *lowest = NULL;
	rb_dlink_node *ptr;

	RB_DLINK_FOREACH(ptr, ssl_daemons.head)
	{
		ctl = ptr->data;
		if(ctl->dead)
			continue;
		if(ctl->shutdown)
			continue;
		if(lowest == NULL)
		{
			lowest = ctl;
			continue;
		}
		if(ctl->cli_count < lowest->cli_count)
			lowest = ctl;
	}
	return (lowest);
}

static void
ssl_write_ctl(rb_fde_t * F, void *data)
{
	ssl_ctl_t *ctl = data;
	ssl_ctl_buf_t *ctl_buf;
	rb_dlink_node *ptr, *next;
	int retlen, x;

	if(ctl->dead)
		return;

	RB_DLINK_FOREACH_SAFE(ptr, next, ctl->writeq.head)
	{
		ctl_buf = ptr->data;
		/* in theory unix sock_dgram shouldn't ever short write this.. */
		retlen = rb_send_fd_buf(ctl->F, ctl_buf->F, ctl_buf->nfds, ctl_buf->buf, ctl_buf->buflen, ctl->pid);
		if(retlen > 0)
		{
			rb_dlinkDelete(ptr, &ctl->writeq);
			for(x = 0; x < ctl_buf->nfds; x++)
				rb_close(ctl_buf->F[x]);
			rb_free(ctl_buf->buf);
			rb_free(ctl_buf);

		}
		if(retlen == 0 || (retlen < 0 && !rb_ignore_errno(errno)))
		{
			ssl_dead(ctl);
			return;
		}
		else
		{
			rb_setselect(ctl->F, RB_SELECT_WRITE, ssl_write_ctl, ctl);
		}
	}
}

static void
ssl_cmd_write_queue(ssl_ctl_t * ctl, rb_fde_t ** F, int count, const void *buf, size_t buflen)
{
	ssl_ctl_buf_t *ctl_buf;
	int x;

	/* don't bother */
	if(ctl->dead)
		return;

	ctl_buf = rb_malloc(sizeof(ssl_ctl_buf_t));
	ctl_buf->buf = rb_malloc(buflen);
	memcpy(ctl_buf->buf, buf, buflen);
	ctl_buf->buflen = buflen;

	for(x = 0; x < count && x < MAXPASSFD; x++)
	{
		ctl_buf->F[x] = F[x];
	}
	ctl_buf->nfds = count;
	rb_dlinkAddTail(ctl_buf, &ctl_buf->node, &ctl->writeq);
	ssl_write_ctl(ctl->F, ctl);
}


static void
send_new_ssl_certs_one(ssl_ctl_t * ctl, const char *ssl_cert, const char *ssl_private_key, const char *ssl_dh_params, const char *ssl_cipher_list)
{
	size_t len;

	len = strlen(ssl_cert) + strlen(ssl_private_key) + strlen(ssl_dh_params) + 5;
	if(len > sizeof(tmpbuf))
	{
		sendto_realops_snomask(SNO_GENERAL, L_ALL,
				       "Parameters for send_new_ssl_certs_one too long (%zu > %zu) to pass to ssld, not sending...",
				       len, sizeof(tmpbuf));
		ilog(L_MAIN,
		     "Parameters for send_new_ssl_certs_one too long (%zu > %zu) to pass to ssld, not sending...",
		     len, sizeof(tmpbuf));
		return;
	}
	len = snprintf(tmpbuf, sizeof(tmpbuf), "K%c%s%c%s%c%s%c%s%c", nul, ssl_cert, nul,
			  ssl_private_key, nul, ssl_dh_params, nul,
			  ssl_cipher_list != NULL ? ssl_cipher_list : "", nul);
	ssl_cmd_write_queue(ctl, NULL, 0, tmpbuf, len);
}

static void
send_init_prng(ssl_ctl_t * ctl, prng_seed_t seedtype, const char *path)
{
	size_t len;
	const char *s;
	uint8_t seed = (uint8_t) seedtype;

	if(path == NULL)
		s = "";
	else
		s = path;

	len = strlen(s) + 3;
	if(len > sizeof(tmpbuf))
	{
		sendto_realops_snomask(SNO_GENERAL, L_ALL,
				       "Parameters for send_init_prng too long (%zd > %zd) to pass to ssld, not sending...",
				       len, sizeof(tmpbuf));
		ilog(L_MAIN,
		     "Parameters for send_init_prng too long (%zd > %zd) to pass to ssld, not sending...",
		     len, sizeof(tmpbuf));
		return;

	}
	len = snprintf(tmpbuf, sizeof(tmpbuf), "I%c%s%c", seed, s, nul);
	ssl_cmd_write_queue(ctl, NULL, 0, tmpbuf, len);
}

static void
send_certfp_method(ssl_ctl_t *ctl, int method)
{
	char buf[5];

	buf[0] = 'F';
	uint32_to_buf(&buf[1], method);
	ssl_cmd_write_queue(ctl, NULL, 0, buf, sizeof(buf));
}

void
send_new_ssl_certs(const char *ssl_cert, const char *ssl_private_key, const char *ssl_dh_params, const char *ssl_cipher_list)
{
	rb_dlink_node *ptr;
	if(ssl_cert == NULL || ssl_private_key == NULL || ssl_dh_params == NULL)
	{
		ircd_ssl_ok = false;
		return;
	}
	RB_DLINK_FOREACH(ptr, ssl_daemons.head)
	{
		ssl_ctl_t *ctl = ptr->data;
		send_new_ssl_certs_one(ctl, ssl_cert, ssl_private_key, ssl_dh_params, ssl_cipher_list);
	}
}


ssl_ctl_t *
start_ssld_accept(rb_fde_t * sslF, rb_fde_t * plainF, uint32_t id)
{
	rb_fde_t *F[2];
	ssl_ctl_t *ctl;
	char buf[5];
	F[0] = sslF;
	F[1] = plainF;

	buf[0] = 'A';
	uint32_to_buf(&buf[1], id);
	ctl = which_ssld();
	if(!ctl)
		return NULL;
	ctl->cli_count++;
	ssl_cmd_write_queue(ctl, F, 2, buf, sizeof(buf));
	return ctl;
}

ssl_ctl_t *
start_ssld_connect(rb_fde_t * sslF, rb_fde_t * plainF, uint32_t id)
{
	rb_fde_t *F[2];
	ssl_ctl_t *ctl;
	char buf[5];
	F[0] = sslF;
	F[1] = plainF;

	buf[0] = 'C';
	uint32_to_buf(&buf[1], id);

	ctl = which_ssld();
	if(!ctl)
		return NULL;
	ctl->cli_count++;
	ssl_cmd_write_queue(ctl, F, 2, buf, sizeof(buf));
	return ctl;
}

void
ssld_decrement_clicount(ssl_ctl_t * ctl)
{
	if(ctl == NULL)
		return;

	ctl->cli_count--;
	if(ctl->shutdown && !ctl->cli_count)
	{
		ctl->dead = 1;
		rb_kill(ctl->pid, SIGKILL);
	}
	if(ctl->dead && !ctl->cli_count)
	{
		free_ssl_daemon(ctl);
	}
}

/*
 * what we end up sending to the ssld process for ziplinks is the following
 * Z[ourfd][level][RECVQ]
 * Z = ziplinks command	= buf[0]
 * ourfd = Our end of the socketpair = buf[1..4]
 * level = zip level buf[5]
 * recvqlen = our recvq len = buf[6-7]
 * recvq = any data we read prior to starting ziplinks
 */
void
start_zlib_session(void *data)
{
	struct Client *server = (struct Client *) data;
	uint16_t recvqlen;
	uint8_t level;
	void *xbuf;

	rb_fde_t *F[2];
	rb_fde_t *xF1, *xF2;
	char *buf;
	char buf2[9];
	void *recvq_start;

	size_t hdr = (sizeof(uint8_t) * 2) + sizeof(uint32_t);
	size_t len;
	int cpylen, left;

	server->localClient->event = NULL;

	recvqlen = rb_linebuf_len(&server->localClient->buf_recvq);

	len = recvqlen + hdr;

	if(len > READBUF_SIZE)
	{
		sendto_realops_snomask(SNO_GENERAL, L_ALL,
				       "ssld - attempted to pass message of %zd len, max len %d, giving up",
				       len, READBUF_SIZE);
		ilog(L_MAIN, "ssld - attempted to pass message of %zd len, max len %d, giving up", len, READBUF_SIZE);
		exit_client(server, server, server, "ssld readbuf exceeded");
		return;
	}

	buf = rb_malloc(len);
	level = ConfigFileEntry.compression_level;

	uint32_to_buf(&buf[1], rb_get_fd(server->localClient->F));
	buf[5] = (char) level;

	recvq_start = &buf[6];
	server->localClient->zipstats = rb_malloc(sizeof(struct ZipStats));

	xbuf = recvq_start;
	left = recvqlen;

	do
	{
		cpylen = rb_linebuf_get(&server->localClient->buf_recvq, xbuf, left, LINEBUF_PARTIAL, LINEBUF_RAW);
		left -= cpylen;
		xbuf = (void *) (((uintptr_t) xbuf) + cpylen);
	}
	while(cpylen > 0);

	/* Pass the socket to ssld. */
	*buf = 'Z';
	if(rb_socketpair(AF_UNIX, SOCK_STREAM, 0, &xF1, &xF2, "Initial zlib socketpairs") == -1)
	{
		sendto_realops_snomask(SNO_GENERAL, L_ALL, "Error creating zlib socketpair - %s", strerror(errno));
		ilog(L_MAIN, "Error creating zlib socketpairs - %s", strerror(errno));
		exit_client(server, server, server, "Error creating zlib socketpair");
		rb_free(buf);
		return;
	}

	if(IsSSL(server))
	{
		/* tell ssld the new connid for the ssl part*/
		buf2[0] = 'Y';
		uint32_to_buf(&buf2[1], rb_get_fd(server->localClient->F));
		uint32_to_buf(&buf2[5], rb_get_fd(xF2));
		ssl_cmd_write_queue(server->localClient->ssl_ctl, NULL, 0, buf2, sizeof(buf2));
	}


	F[0] = server->localClient->F;
	F[1] = xF1;
	del_from_zconnid_hash(server);
	server->localClient->F = xF2;
	/* need to redo as what we did before isn't valid now */
	uint32_to_buf(&buf[1], server->localClient->zconnid);
	add_to_zconnid_hash(server);

	server->localClient->z_ctl = which_ssld();
	if(!server->localClient->z_ctl)
	{
		exit_client(server, server, server, "Error finding available ssld");
		rb_free(buf);
		return;
	}
	server->localClient->z_ctl->cli_count++;
	ssl_cmd_write_queue(server->localClient->z_ctl, F, 2, buf, len);
	rb_free(buf);
}

static void
collect_zipstats(void *unused)
{
	rb_dlink_node *ptr;
	struct Client *target_p;
	char buf[sizeof(uint8_t) + sizeof(uint32_t) + HOSTLEN];
	void *odata;
	size_t len;
	uint32_t id;

	buf[0] = 'S';
	odata = buf + sizeof(uint8_t) + sizeof(uint32_t);

	RB_DLINK_FOREACH(ptr, serv_list.head)
	{
		target_p = ptr->data;
		if(IsCapable(target_p, CAP_ZIP))
		{
			len = sizeof(uint8_t) + sizeof(uint32_t);

			id = rb_get_fd(target_p->localClient->F);
			uint32_to_buf(&buf[1], id);
			rb_strlcpy(odata, target_p->name, (sizeof(buf) - len));
			len += strlen(odata) + 1;	/* Get the \0 as well */
			ssl_cmd_write_queue(target_p->localClient->z_ctl, NULL, 0, buf, len);
		}
	}
}

static void
cleanup_dead_ssl(void *unused)
{
	rb_dlink_node *ptr, *next;
	ssl_ctl_t *ctl;
	RB_DLINK_FOREACH_SAFE(ptr, next, ssl_daemons.head)
	{
		ctl = ptr->data;
		if(ctl->dead && !ctl->cli_count)
		{
			free_ssl_daemon(ctl);
		}
	}
}

int
get_ssld_count(void)
{
	return ssld_count;
}

void
ssld_foreach_info(void (*func)(void *data, pid_t pid, int cli_count, enum ssld_status status, const char *version), void *data)
{
	rb_dlink_node *ptr, *next;
	ssl_ctl_t *ctl;
	RB_DLINK_FOREACH_SAFE(ptr, next, ssl_daemons.head)
	{
		ctl = ptr->data;
		func(data, ctl->pid, ctl->cli_count,
			ctl->dead ? SSLD_DEAD :
				(ctl->shutdown ? SSLD_SHUTDOWN : SSLD_ACTIVE),
			ctl->version);
	}
}

void
init_ssld(void)
{
	rb_event_addish("collect_zipstats", collect_zipstats, NULL, ZIPSTATS_TIME);
	rb_event_addish("cleanup_dead_ssld", cleanup_dead_ssl, NULL, 60);
}