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|
/*++
/* NAME
/* scache_clnt 3
/* SUMMARY
/* session cache manager client
/* SYNOPSIS
/* #include <scache.h>
/* DESCRIPTION
/* SCACHE *scache_clnt_create(server, timeout, idle_limit, ttl_limit)
/* const char *server;
/* int timeout;
/* int idle_limit;
/* int ttl_limit;
/* DESCRIPTION
/* This module implements the client-side protocol of the
/* session cache service.
/*
/* scache_clnt_create() creates a session cache service client.
/*
/* Arguments:
/* .IP server
/* The session cache service name.
/* .IP timeout
/* Time limit for connect, send or receive operations.
/* .IP idle_limit
/* Idle time after which the client disconnects.
/* .IP ttl_limit
/* Upper bound on the time that a connection is allowed to persist.
/* DIAGNOSTICS
/* Fatal error: memory allocation problem;
/* warning: communication error;
/* panic: internal consistency failure.
/* SEE ALSO
/* scache(3), generic session cache API
/* LICENSE
/* .ad
/* .fi
/* The Secure Mailer license must be distributed with this software.
/* AUTHOR(S)
/* Wietse Venema
/* IBM T.J. Watson Research
/* P.O. Box 704
/* Yorktown Heights, NY 10598, USA
/*
/* Wietse Venema
/* Google, Inc.
/* 111 8th Avenue
/* New York, NY 10011, USA
/*--*/
/* System library. */
#include <sys_defs.h>
#include <errno.h>
/* Utility library. */
#include <msg.h>
#include <mymalloc.h>
#include <auto_clnt.h>
#include <stringops.h>
/*#define msg_verbose 1*/
/* Global library. */
#include <mail_proto.h>
#include <mail_params.h>
#include <scache.h>
/* Application-specific. */
/*
* SCACHE_CLNT is a derived type from the SCACHE super-class.
*/
typedef struct {
SCACHE scache[1]; /* super-class */
AUTO_CLNT *auto_clnt; /* client endpoint */
#ifdef CANT_WRITE_BEFORE_SENDING_FD
VSTRING *dummy; /* dummy buffer */
#endif
} SCACHE_CLNT;
#define STR(x) vstring_str(x)
#define SCACHE_MAX_TRIES 2
/* scache_clnt_handshake - receive server protocol announcement */
static int scache_clnt_handshake(VSTREAM *stream)
{
return (attr_scan(stream, ATTR_FLAG_STRICT,
RECV_ATTR_STREQ(MAIL_ATTR_PROTO, MAIL_ATTR_PROTO_SCACHE),
ATTR_TYPE_END));
}
/* scache_clnt_save_endp - save endpoint */
static void scache_clnt_save_endp(SCACHE *scache, int endp_ttl,
const char *endp_label,
const char *endp_prop, int fd)
{
SCACHE_CLNT *sp = (SCACHE_CLNT *) scache;
const char *myname = "scache_clnt_save_endp";
VSTREAM *stream;
int status;
int tries;
int count = 0;
if (msg_verbose)
msg_info("%s: endp=%s prop=%s fd=%d",
myname, endp_label, endp_prop, fd);
/*
* Sanity check.
*/
if (endp_ttl <= 0)
msg_panic("%s: bad endp_ttl: %d", myname, endp_ttl);
/*
* Try a few times before disabling the cache. We use synchronous calls;
* the session cache service is CPU bound and making the client
* asynchronous would just complicate the code.
*/
for (tries = 0; sp->auto_clnt != 0; tries++) {
if ((stream = auto_clnt_access(sp->auto_clnt)) != 0) {
errno = 0;
count += 1;
if (attr_print(stream, ATTR_FLAG_NONE,
SEND_ATTR_STR(MAIL_ATTR_REQ, SCACHE_REQ_SAVE_ENDP),
SEND_ATTR_INT(MAIL_ATTR_TTL, endp_ttl),
SEND_ATTR_STR(MAIL_ATTR_LABEL, endp_label),
SEND_ATTR_STR(MAIL_ATTR_PROP, endp_prop),
ATTR_TYPE_END) != 0
|| vstream_fflush(stream)
#ifdef CANT_WRITE_BEFORE_SENDING_FD
|| attr_scan(stream, ATTR_FLAG_STRICT,
RECV_ATTR_STR(MAIL_ATTR_DUMMY, sp->dummy),
ATTR_TYPE_END) != 1
#endif
|| LOCAL_SEND_FD(vstream_fileno(stream), fd) < 0
|| attr_scan(stream, ATTR_FLAG_STRICT,
RECV_ATTR_INT(MAIL_ATTR_STATUS, &status),
ATTR_TYPE_END) != 1) {
if (msg_verbose || count > 1 || (errno && errno != EPIPE && errno != ENOENT))
msg_warn("problem talking to service %s: %m",
VSTREAM_PATH(stream));
/* Give up or recover. */
} else {
if (msg_verbose && status != 0)
msg_warn("%s: descriptor save failed with status %d",
myname, status);
break;
}
}
/* Give up or recover. */
if (tries >= SCACHE_MAX_TRIES - 1) {
msg_warn("disabling connection caching");
auto_clnt_free(sp->auto_clnt);
sp->auto_clnt = 0;
break;
}
sleep(1); /* XXX make configurable */
auto_clnt_recover(sp->auto_clnt);
}
/* Always close the descriptor before returning. */
if (close(fd) < 0)
msg_warn("%s: close(%d): %m", myname, fd);
}
/* scache_clnt_find_endp - look up cached session */
static int scache_clnt_find_endp(SCACHE *scache, const char *endp_label,
VSTRING *endp_prop)
{
SCACHE_CLNT *sp = (SCACHE_CLNT *) scache;
const char *myname = "scache_clnt_find_endp";
VSTREAM *stream;
int status;
int tries;
int fd;
/*
* Try a few times before disabling the cache. We use synchronous calls;
* the session cache service is CPU bound and making the client
* asynchronous would just complicate the code.
*/
for (tries = 0; sp->auto_clnt != 0; tries++) {
if ((stream = auto_clnt_access(sp->auto_clnt)) != 0) {
errno = 0;
if (attr_print(stream, ATTR_FLAG_NONE,
SEND_ATTR_STR(MAIL_ATTR_REQ, SCACHE_REQ_FIND_ENDP),
SEND_ATTR_STR(MAIL_ATTR_LABEL, endp_label),
ATTR_TYPE_END) != 0
|| vstream_fflush(stream)
|| attr_scan(stream, ATTR_FLAG_STRICT,
RECV_ATTR_INT(MAIL_ATTR_STATUS, &status),
RECV_ATTR_STR(MAIL_ATTR_PROP, endp_prop),
ATTR_TYPE_END) != 2) {
if (msg_verbose || (errno != EPIPE && errno != ENOENT))
msg_warn("problem talking to service %s: %m",
VSTREAM_PATH(stream));
/* Give up or recover. */
} else if (status != 0) {
if (msg_verbose)
msg_info("%s: not found: %s", myname, endp_label);
return (-1);
} else if (
#ifdef CANT_WRITE_BEFORE_SENDING_FD
attr_print(stream, ATTR_FLAG_NONE,
SEND_ATTR_STR(MAIL_ATTR_DUMMY, ""),
ATTR_TYPE_END) != 0
|| vstream_fflush(stream) != 0
|| read_wait(vstream_fileno(stream),
stream->timeout) < 0 || /* XXX */
#endif
(fd = LOCAL_RECV_FD(vstream_fileno(stream))) < 0) {
if (msg_verbose || (errno != EPIPE && errno != ENOENT))
msg_warn("problem talking to service %s: %m",
VSTREAM_PATH(stream));
/* Give up or recover. */
} else {
#ifdef MUST_READ_AFTER_SENDING_FD
(void) attr_print(stream, ATTR_FLAG_NONE,
SEND_ATTR_STR(MAIL_ATTR_DUMMY, ""),
ATTR_TYPE_END);
(void) vstream_fflush(stream);
#endif
if (msg_verbose)
msg_info("%s: endp=%s prop=%s fd=%d",
myname, endp_label, STR(endp_prop), fd);
return (fd);
}
}
/* Give up or recover. */
if (tries >= SCACHE_MAX_TRIES - 1) {
msg_warn("disabling connection caching");
auto_clnt_free(sp->auto_clnt);
sp->auto_clnt = 0;
return (-1);
}
sleep(1); /* XXX make configurable */
auto_clnt_recover(sp->auto_clnt);
}
return (-1);
}
/* scache_clnt_save_dest - create destination/endpoint association */
static void scache_clnt_save_dest(SCACHE *scache, int dest_ttl,
const char *dest_label,
const char *dest_prop,
const char *endp_label)
{
SCACHE_CLNT *sp = (SCACHE_CLNT *) scache;
const char *myname = "scache_clnt_save_dest";
VSTREAM *stream;
int status;
int tries;
if (msg_verbose)
msg_info("%s: dest_label=%s dest_prop=%s endp_label=%s",
myname, dest_label, dest_prop, endp_label);
/*
* Sanity check.
*/
if (dest_ttl <= 0)
msg_panic("%s: bad dest_ttl: %d", myname, dest_ttl);
/*
* Try a few times before disabling the cache. We use synchronous calls;
* the session cache service is CPU bound and making the client
* asynchronous would just complicate the code.
*/
for (tries = 0; sp->auto_clnt != 0; tries++) {
if ((stream = auto_clnt_access(sp->auto_clnt)) != 0) {
errno = 0;
if (attr_print(stream, ATTR_FLAG_NONE,
SEND_ATTR_STR(MAIL_ATTR_REQ, SCACHE_REQ_SAVE_DEST),
SEND_ATTR_INT(MAIL_ATTR_TTL, dest_ttl),
SEND_ATTR_STR(MAIL_ATTR_LABEL, dest_label),
SEND_ATTR_STR(MAIL_ATTR_PROP, dest_prop),
SEND_ATTR_STR(MAIL_ATTR_LABEL, endp_label),
ATTR_TYPE_END) != 0
|| vstream_fflush(stream)
|| attr_scan(stream, ATTR_FLAG_STRICT,
RECV_ATTR_INT(MAIL_ATTR_STATUS, &status),
ATTR_TYPE_END) != 1) {
if (msg_verbose || (errno != EPIPE && errno != ENOENT))
msg_warn("problem talking to service %s: %m",
VSTREAM_PATH(stream));
/* Give up or recover. */
} else {
if (msg_verbose && status != 0)
msg_warn("%s: destination save failed with status %d",
myname, status);
break;
}
}
/* Give up or recover. */
if (tries >= SCACHE_MAX_TRIES - 1) {
msg_warn("disabling connection caching");
auto_clnt_free(sp->auto_clnt);
sp->auto_clnt = 0;
break;
}
sleep(1); /* XXX make configurable */
auto_clnt_recover(sp->auto_clnt);
}
}
/* scache_clnt_find_dest - look up cached session */
static int scache_clnt_find_dest(SCACHE *scache, const char *dest_label,
VSTRING *dest_prop,
VSTRING *endp_prop)
{
SCACHE_CLNT *sp = (SCACHE_CLNT *) scache;
const char *myname = "scache_clnt_find_dest";
VSTREAM *stream;
int status;
int tries;
int fd;
/*
* Try a few times before disabling the cache. We use synchronous calls;
* the session cache service is CPU bound and making the client
* asynchronous would just complicate the code.
*/
for (tries = 0; sp->auto_clnt != 0; tries++) {
if ((stream = auto_clnt_access(sp->auto_clnt)) != 0) {
errno = 0;
if (attr_print(stream, ATTR_FLAG_NONE,
SEND_ATTR_STR(MAIL_ATTR_REQ, SCACHE_REQ_FIND_DEST),
SEND_ATTR_STR(MAIL_ATTR_LABEL, dest_label),
ATTR_TYPE_END) != 0
|| vstream_fflush(stream)
|| attr_scan(stream, ATTR_FLAG_STRICT,
RECV_ATTR_INT(MAIL_ATTR_STATUS, &status),
RECV_ATTR_STR(MAIL_ATTR_PROP, dest_prop),
RECV_ATTR_STR(MAIL_ATTR_PROP, endp_prop),
ATTR_TYPE_END) != 3) {
if (msg_verbose || (errno != EPIPE && errno != ENOENT))
msg_warn("problem talking to service %s: %m",
VSTREAM_PATH(stream));
/* Give up or recover. */
} else if (status != 0) {
if (msg_verbose)
msg_info("%s: not found: %s", myname, dest_label);
return (-1);
} else if (
#ifdef CANT_WRITE_BEFORE_SENDING_FD
attr_print(stream, ATTR_FLAG_NONE,
SEND_ATTR_STR(MAIL_ATTR_DUMMY, ""),
ATTR_TYPE_END) != 0
|| vstream_fflush(stream) != 0
|| read_wait(vstream_fileno(stream),
stream->timeout) < 0 || /* XXX */
#endif
(fd = LOCAL_RECV_FD(vstream_fileno(stream))) < 0) {
if (msg_verbose || (errno != EPIPE && errno != ENOENT))
msg_warn("problem talking to service %s: %m",
VSTREAM_PATH(stream));
/* Give up or recover. */
} else {
#ifdef MUST_READ_AFTER_SENDING_FD
(void) attr_print(stream, ATTR_FLAG_NONE,
SEND_ATTR_STR(MAIL_ATTR_DUMMY, ""),
ATTR_TYPE_END);
(void) vstream_fflush(stream);
#endif
if (msg_verbose)
msg_info("%s: dest=%s dest_prop=%s endp_prop=%s fd=%d",
myname, dest_label, STR(dest_prop), STR(endp_prop), fd);
return (fd);
}
}
/* Give up or recover. */
if (tries >= SCACHE_MAX_TRIES - 1) {
msg_warn("disabling connection caching");
auto_clnt_free(sp->auto_clnt);
sp->auto_clnt = 0;
return (-1);
}
sleep(1); /* XXX make configurable */
auto_clnt_recover(sp->auto_clnt);
}
return (-1);
}
/* scache_clnt_size - dummy */
static void scache_clnt_size(SCACHE *unused_scache, SCACHE_SIZE *size)
{
/* XXX Crap in a hurry. */
size->dest_count = 0;
size->endp_count = 0;
size->sess_count = 0;
}
/* scache_clnt_free - destroy cache */
static void scache_clnt_free(SCACHE *scache)
{
SCACHE_CLNT *sp = (SCACHE_CLNT *) scache;
if (sp->auto_clnt)
auto_clnt_free(sp->auto_clnt);
#ifdef CANT_WRITE_BEFORE_SENDING_FD
vstring_free(sp->dummy);
#endif
myfree((void *) sp);
}
/* scache_clnt_create - initialize */
SCACHE *scache_clnt_create(const char *server, int timeout,
int idle_limit, int ttl_limit)
{
SCACHE_CLNT *sp = (SCACHE_CLNT *) mymalloc(sizeof(*sp));
char *service;
sp->scache->save_endp = scache_clnt_save_endp;
sp->scache->find_endp = scache_clnt_find_endp;
sp->scache->save_dest = scache_clnt_save_dest;
sp->scache->find_dest = scache_clnt_find_dest;
sp->scache->size = scache_clnt_size;
sp->scache->free = scache_clnt_free;
service = concatenate("local:" MAIL_CLASS_PRIVATE "/", server, (char *) 0);
sp->auto_clnt = auto_clnt_create(service, timeout, idle_limit, ttl_limit);
auto_clnt_control(sp->auto_clnt,
AUTO_CLNT_CTL_HANDSHAKE, scache_clnt_handshake,
AUTO_CLNT_CTL_END);
myfree(service);
#ifdef CANT_WRITE_BEFORE_SENDING_FD
sp->dummy = vstring_alloc(1);
#endif
return (sp->scache);
}
|
