/*++
* Function: SetBannerAndCapability
*
* Purpose: Connect to an IMAP server as a client and fetch the initial
* banner string and the output from a CAPABILITY command.
*
* Parameters: none
*
* Returns: nuttin -- exits if there's a problem
*
* Authors: Dave McMurtrie <*****@*****.**>
*
* Notes: All AUTH mechanisms will be stripped from the capability
* string. AUTH=LOGIN will be added.
* The support_unselect flag in the global copy of the
* ProxyConfig struct will be set in this function depending on
* whether the server supports UNSELECT or not.
*--
*/
static void SetBannerAndCapability( void )
{
int sd;
ITD_Struct itd;
ICD_Struct conn;
int BytesRead;
char *fn = "SetBannerAndCapability()";
int NumRef = 0;
/* initialize some stuff */
memset( &itd, 0, sizeof itd );
for ( ;; )
{
sd = socket( PF_INET, SOCK_STREAM, IPPROTO_TCP );
if ( sd == -1 )
{
syslog(LOG_ERR, "%s: socket() failed: %s -- exiting", fn,
strerror(errno) );
exit( 1 );
}
if ( connect( sd, (struct sockaddr *)&ISD.srv, sizeof(ISD.srv) ) == -1 )
{
syslog(LOG_ERR, "%s: connect() to imap server on socket [%d] failed: %s", fn, sd, strerror(errno));
close( sd );
if ( errno == ECONNREFUSED && ++NumRef < 10 )
{
sleep( 60 ); /* IMAP server may not be started yet. */
continue;
}
syslog( LOG_ERR, "%s: unable to connect() to imap server and retry limit exceeded -- exiting.", fn );
exit( 1 );
}
break; /* Success */
}
memset( &conn, 0, sizeof ( ICD_Struct ) );
itd.conn = &conn;
itd.conn->sd = sd;
/*
* The first thing we get back from the server should be the
* banner string.
*/
BytesRead = IMAP_Line_Read( &itd );
if ( BytesRead == -1 )
{
syslog( LOG_ERR, "%s: Error reading banner line from server on initial connection: %s -- Exiting.", fn, strerror( errno ) );
close( itd.conn->sd );
exit( 1 );
}
if ( itd.LiteralBytesRemaining )
{
syslog( LOG_ERR, "%s: Server sent unexpected literal specifier in banner response -- Exiting.", fn );
exit( 1 );
}
BannerLen = ParseBannerAndCapability( Banner, sizeof Banner - 1,
itd.ReadBuf, BytesRead );
/*
* See if the string we got back starts with "* OK" by comparing the
* first 4 characters of the buffer.
*/
if ( strncasecmp( Banner, IMAP_UNTAGGED_OK, strlen(IMAP_UNTAGGED_OK)) )
{
syslog(LOG_ERR, "%s: Unexpected response from imap server on initial connection: %s -- Exiting.", fn, Banner);
close( itd.conn->sd );
exit( 1 );
}
/* Now we send a CAPABILITY command to the server. */
if ( IMAP_Write( itd.conn, "1 CAPABILITY\r\n", strlen("1 CAPABILITY\r\n") ) == -1 )
{
syslog(LOG_ERR, "%s: Unable to send capability command to server: %s -- exiting.", fn, strerror(errno) );
close( itd.conn->sd );
exit( 1 );
}
/*
* From RFC2060:
* The server MUST send a single untagged
* CAPABILITY response with "IMAP4rev1" as one of the listed
* capabilities before the (tagged) OK response.
*
* The means we should read exactly 2 lines of data back from the server.
* The first will be the untagged capability line.
* The second will be the OK response with the tag in it.
*/
BytesRead = IMAP_Line_Read( &itd );
if ( BytesRead == -1 )
{
syslog( LOG_ERR, "%s: Failed to read capability response from server: %s -- exiting.", fn, strerror( errno ) );
close( itd.conn->sd );
exit( 1 );
}
if ( itd.LiteralBytesRemaining )
{
syslog( LOG_ERR, "%s: Server sent unexpected literal specifier in CAPABILITY response -- Exiting.", fn );
close( itd.conn->sd );
exit ( 1 );
}
CapabilityLen = ParseBannerAndCapability( Capability, sizeof Capability - 1,
itd.ReadBuf, BytesRead );
/* Now read the tagged response and make sure it's OK */
BytesRead = IMAP_Line_Read( &itd );
if ( BytesRead == -1 )
{
syslog( LOG_ERR, "%s: Failed to read capability response from server: %s -- exiting.", fn, strerror( errno ) );
close( itd.conn->sd );
exit( 1 );
}
if ( itd.LiteralBytesRemaining )
{
syslog( LOG_ERR, "%s: Server sent unexpected literal specifier in tagged CAPABILITY response -- exiting.", fn );
exit( 1 );
}
if ( strncasecmp( itd.ReadBuf, IMAP_TAGGED_OK, strlen(IMAP_TAGGED_OK) ) )
{
syslog(LOG_ERR, "%s: Received non-OK tagged reponse from imap server on CAPABILITY command -- exiting.", fn );
close( itd.conn->sd );
exit( 1 );
}
/* Be nice and logout */
if ( IMAP_Write( itd.conn, "2 LOGOUT\r\n", strlen("2 LOGOUT\r\n") ) == -1 )
{
syslog(LOG_WARNING, "%s: IMAP_Write() failed on LOGOUT: %s -- Ignoring", fn, strerror(errno) );
close( itd.conn->sd );
return;
}
/* read the final OK logout */
BytesRead = IMAP_Line_Read( &itd );
if ( BytesRead == -1 )
{
syslog(LOG_WARNING, "%s: IMAP_Line_Read() failed on LOGOUT -- Ignoring", fn );
}
if ( itd.LiteralBytesRemaining )
{
syslog( LOG_WARNING, "%s: Server sent unexpected literal specifier in LOGOUT response -- Ignoring", fn );
}
close( itd.conn->sd );
return;
}
/*++
* Function: SetBannerAndCapability
*
* Purpose: Connect to an IMAP server as a client and fetch the initial
* banner string and the output from a CAPABILITY command.
*
* Parameters: none
*
* Returns: nuttin -- exits if there's a problem
*
* Authors: Dave McMurtrie <*****@*****.**>
*
* Notes: All AUTH mechanisms will be stripped from the capability
* string. AUTH=LOGIN will be added.
* The support_unselect flag in the global copy of the
* ProxyConfig struct will be set in this function depending on
* whether the server supports UNSELECT or not.
*--
*/
static void SetBannerAndCapability( void )
{
int sd;
ITD_Struct itd;
ICD_Struct conn;
int BytesRead;
char *fn = "SetBannerAndCapability()";
/* initialize some stuff */
memset( &itd, 0, sizeof itd );
for ( ;; )
{
sd = socket( ISD.srv->ai_family, ISD.srv->ai_socktype,
ISD.srv->ai_protocol );
if ( sd == -1 )
{
syslog(LOG_ERR, "%s: socket() failed: %s -- exiting", fn,
strerror(errno) );
exit( 1 );
}
if ( connect( sd, (struct sockaddr *)ISD.srv->ai_addr,
ISD.srv->ai_addrlen ) == -1 ) {
syslog(LOG_ERR, "%s: connect() to IMAP server on socket [%d] failed: %s -- retrying", fn, sd, strerror(errno));
close( sd );
sleep( 15 ); /* IMAP server may not be started yet. */
}
else
{
break; /* Success */
}
}
memset( &conn, 0, sizeof ( ICD_Struct ) );
itd.conn = &conn;
itd.conn->sd = sd;
/*
* The first thing we get back from the server should be the
* banner string.
*/
BytesRead = IMAP_Line_Read( &itd );
if ( BytesRead == -1 )
{
syslog( LOG_ERR, "%s: Error reading banner line from server on initial connection: %s -- Exiting.", fn, strerror( errno ) );
close( itd.conn->sd );
exit( 1 );
}
if ( itd.LiteralBytesRemaining )
{
syslog( LOG_ERR, "%s: Server sent unexpected literal specifier in banner response -- Exiting.", fn );
exit( 1 );
}
BannerLen = ParseBannerAndCapability( Banner, sizeof Banner - 1,
itd.ReadBuf, BytesRead, 0 );
/*
* See if the string we got back starts with "* OK" by comparing the
* first 4 characters of the buffer.
*/
if ( strncasecmp( Banner, IMAP_UNTAGGED_OK, strlen(IMAP_UNTAGGED_OK)) )
{
syslog(LOG_ERR, "%s: Unexpected response from IMAP server on initial connection: %s -- Exiting.", fn, Banner);
close( itd.conn->sd );
exit( 1 );
}
/* Now we send a CAPABILITY command to the server. */
if ( IMAP_Write( itd.conn, "1 CAPABILITY\r\n", strlen("1 CAPABILITY\r\n") ) == -1 )
{
syslog(LOG_ERR, "%s: Unable to send capability command to server: %s -- exiting.", fn, strerror(errno) );
close( itd.conn->sd );
exit( 1 );
}
/*
* From RFC2060:
* The server MUST send a single untagged
* CAPABILITY response with "IMAP4rev1" as one of the listed
* capabilities before the (tagged) OK response.
*
* The means we should read exactly 2 lines of data back from the server.
* The first will be the untagged capability line.
* The second will be the OK response with the tag in it.
*/
BytesRead = IMAP_Line_Read( &itd );
if ( BytesRead == -1 )
{
syslog( LOG_ERR, "%s: Failed to read capability response from server: %s -- exiting.", fn, strerror( errno ) );
close( itd.conn->sd );
exit( 1 );
}
if ( itd.LiteralBytesRemaining )
{
syslog( LOG_ERR, "%s: Server sent unexpected literal specifier in CAPABILITY response -- Exiting.", fn );
close( itd.conn->sd );
exit ( 1 );
}
CapabilityLen = ParseBannerAndCapability( Capability, sizeof Capability - 1,
itd.ReadBuf, BytesRead, 1 );
/* Now read the tagged response and make sure it's OK */
BytesRead = IMAP_Line_Read( &itd );
if ( BytesRead == -1 )
{
syslog( LOG_ERR, "%s: Failed to read capability response from server: %s -- exiting.", fn, strerror( errno ) );
close( itd.conn->sd );
exit( 1 );
}
if ( itd.LiteralBytesRemaining )
{
syslog( LOG_ERR, "%s: Server sent unexpected literal specifier in tagged CAPABILITY response -- exiting.", fn );
exit( 1 );
}
if ( strncasecmp( itd.ReadBuf, IMAP_TAGGED_OK, strlen(IMAP_TAGGED_OK) ) )
{
syslog(LOG_ERR, "%s: Received non-OK tagged reponse from IMAP server on CAPABILITY command -- exiting.", fn );
close( itd.conn->sd );
exit( 1 );
}
/*
* If we're using it, attempt STARTTLS before doing one more
* CAPABILITY so our capability string is accurate
*/
if ( PC_Struct.login_disabled || PC_Struct.force_tls )
{
#if HAVE_LIBSSL
if ( PC_Struct.support_starttls != STARTTLS_NOT_SUPPORTED )
{
if ( Attempt_STARTTLS( &itd ) != 0 )
{
syslog(LOG_ERR, "%s: STARTTLS failed for CAPABILITY check -- exiting.", fn );
close( itd.conn->sd );
exit( 1 );
}
else
{
/*
* STARTTLS was successful, so we can proceed
* to get the new CAPABILITY list - first,
* send a CAPABILITY command to the server.
*/
if ( IMAP_Write( itd.conn, "1 CAPABILITY\r\n", strlen("1 CAPABILITY\r\n") ) == -1 )
{
syslog(LOG_ERR, "%s: Unable to send capability command to server: %s -- exiting.", fn, strerror(errno) );
close( itd.conn->sd );
exit( 1 );
}
/*
* From RFC2060:
* The server MUST send a single untagged
* CAPABILITY response with "IMAP4rev1" as one of the listed
* capabilities before the (tagged) OK response.
*
* The means we should read exactly 2 lines of data back from the server.
* The first will be the untagged capability line.
* The second will be the OK response with the tag in it.
*/
BytesRead = IMAP_Line_Read( &itd );
if ( BytesRead == -1 )
{
syslog( LOG_ERR, "%s: Failed to read capability response from server: %s -- exiting.", fn, strerror( errno ) );
close( itd.conn->sd );
exit( 1 );
}
if ( itd.LiteralBytesRemaining )
{
syslog( LOG_ERR, "%s: Server sent unexpected literal specifier in CAPABILITY response -- Exiting.", fn );
close( itd.conn->sd );
exit ( 1 );
}
CapabilityLen = ParseBannerAndCapability( Capability, sizeof Capability - 1,
itd.ReadBuf, BytesRead, 1 );
/* Now read the tagged response and make sure it's OK */
BytesRead = IMAP_Line_Read( &itd );
if ( BytesRead == -1 )
{
syslog( LOG_ERR, "%s: Failed to read capability response from server: %s -- exiting.", fn, strerror( errno ) );
close( itd.conn->sd );
exit( 1 );
}
if ( itd.LiteralBytesRemaining )
{
syslog( LOG_ERR, "%s: Server sent unexpected literal specifier in tagged CAPABILITY response -- exiting.", fn );
exit( 1 );
}
if ( strncasecmp( itd.ReadBuf, IMAP_TAGGED_OK, strlen(IMAP_TAGGED_OK) ) )
{
syslog(LOG_ERR, "%s: Received non-OK tagged reponse from imap server on CAPABILITY command -- exiting.", fn );
close( itd.conn->sd );
exit( 1 );
}
}
}
else
#endif /* HAVE_LIBSSL */
{
/* We're screwed! We won't be able to login without SASL */
syslog(LOG_ERR,
"%s: IMAP server has LOGINDISABLED and we can't do STARTTLS. Exiting.",
fn);
close( itd.conn->sd );
exit( 1 );
}
}
else
{
//syslog( LOG_ERR, "%s: Not trying STARTTLS and second CAPABILITY.", fn );
}
/* Be nice and logout */
if ( IMAP_Write( itd.conn, "2 LOGOUT\r\n", strlen("2 LOGOUT\r\n") ) == -1 )
{
syslog(LOG_WARNING, "%s: IMAP_Write() failed on LOGOUT: %s -- Ignoring", fn, strerror(errno) );
close( itd.conn->sd );
return;
}
/* read the final OK logout */
BytesRead = IMAP_Line_Read( &itd );
if ( BytesRead == -1 )
{
syslog(LOG_WARNING, "%s: IMAP_Line_Read() failed on LOGOUT -- Ignoring", fn );
}
if ( itd.LiteralBytesRemaining )
{
syslog( LOG_WARNING, "%s: Server sent unexpected literal specifier in LOGOUT response -- Ignoring", fn );
}
close( itd.conn->sd );
return;
}
