xrdp/libipm/libipm_send.c

617 lines
17 KiB
C

/**
* Copyright (C) 2022 Matt Burt, all xrdp contributors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* @file libipm/libipm.c
* @brief Inter-Process Messaging building and parsing definitions
*/
#if defined(HAVE_CONFIG_H)
#include <config_ac.h>
#endif
#include <stdio.h>
#include <stdarg.h>
#include "libipm.h"
#include "libipm_private.h"
#include "libipm_facilities.h"
#include "trans.h"
#include "log.h"
#include "os_calls.h"
#include "string_calls.h"
/**************************************************************************//**
* Log an output appending error
*
* @param trans libipm transport
* @param format printf-like format descriptor
*/
printflike(2, 3) static void
log_append_error(struct trans *trans, const char *format, ...)
{
struct libipm_priv *priv = (struct libipm_priv *)trans->extra_data;
const char *msgno_str = NULL;
char msgno_str_buff[32];
char buff[256];
unsigned int len;
/* Find a string for the message number */
if (priv->msgno_to_str != NULL)
{
msgno_str = priv->msgno_to_str(priv->out_msgno);
}
if (msgno_str == NULL)
{
g_snprintf(msgno_str_buff, sizeof(msgno_str_buff),
"[code #%d]", priv->out_msgno);
msgno_str = msgno_str_buff;
}
len = g_snprintf(buff, sizeof(buff),
"Error creating ipm message for %s, parameter %d :",
msgno_str, priv->out_param_count);
if (len < sizeof(buff))
{
va_list ap;
va_start(ap, format);
vsnprintf(&buff[len], sizeof(buff) - len, format, ap);
va_end(ap);
}
LOG(LOG_LEVEL_ERROR, "%s", buff);
}
/* Common format string for overflow reporting */
static const char *
not_enough_output_msg = "Not enough space in output buffer for '%c'";
/* Common format string for bad value reporting */
static const char *
bad_value_msg = "Type '%c' has unsupported value '%d'";
/**************************************************************************//**
* Add a bool to the output stream
*
* @param c Type letter which triggered the call
* @param trans libipm transport
* @param argptr Pointer to value in argument stack (promoted to int)
* @return != 0 for error
*
* The boolean value must be a 0 or a 1.
*/
static enum libipm_status
append_bool_type(char c, struct trans *trans, va_list *argptr)
{
enum libipm_status rv = E_LI_SUCCESS;
struct stream *s = trans->out_s;
if (!s_check_rem_out(s, 1 + 1))
{
log_append_error(trans, not_enough_output_msg, c);
rv = E_LI_BUFFER_OVERFLOW;
}
else
{
int tmp = va_arg(*argptr, int);
if (tmp < 0 || tmp > 1)
{
log_append_error(trans, bad_value_msg, c, tmp);
rv = E_LI_BAD_VALUE;
}
else
{
out_uint8(s, c);
out_uint8(s, tmp);
}
}
return rv;
}
/**************************************************************************//**
* Add an octet to the output stream
*
* @param c Type letter which triggered the call
* @param trans libipm transport
* @param argptr Pointer to value in argument stack (promoted to int)
* @return != 0 for error
*/
static enum libipm_status
append_int8_type(char c, struct trans *trans, va_list *argptr)
{
enum libipm_status rv = E_LI_SUCCESS;
struct stream *s = trans->out_s;
if (!s_check_rem_out(s, 1 + 1))
{
log_append_error(trans, not_enough_output_msg, c);
rv = E_LI_BUFFER_OVERFLOW;
}
else
{
int tmp = va_arg(*argptr, int);
if (tmp < 0 || tmp > 255)
{
log_append_error(trans, bad_value_msg, c, tmp);
rv = E_LI_BAD_VALUE;
}
else
{
out_uint8(s, c);
out_uint8(s, tmp);
}
}
return rv;
}
/**************************************************************************//**
* Add an 16-bit integer to the output stream
*
* @param c Type letter which triggered the call
* @param trans libipm transport
* @param argptr Pointer to value in argument stack (promoted to int)
* @return != 0 for error
*/
static enum libipm_status
append_int16_type(char c, struct trans *trans, va_list *argptr)
{
enum libipm_status rv = E_LI_SUCCESS;
struct stream *s = trans->out_s;
if (!s_check_rem_out(s, 1 + 2))
{
log_append_error(trans, not_enough_output_msg, c);
rv = E_LI_BUFFER_OVERFLOW;
}
else
{
int tmp = va_arg(*argptr, int);
if ((c == 'n' && (tmp < -0x8000 || tmp > 0x7fff)) ||
(c == 'q' && (tmp < 0 || tmp > 0xffff)))
{
log_append_error(trans, bad_value_msg, c, tmp);
rv = E_LI_BAD_VALUE;
}
else
{
out_uint8(s, c);
out_uint16_le(s, tmp);
}
}
return rv;
}
/**************************************************************************//**
* Add a 32-bit integer to the output stream
*
* @param c Type letter which triggered the call
* @param trans libipm transport
* @param argptr Pointer to value in argument stack
* @return != 0 for error
*/
static enum libipm_status
append_int32_type(char c, struct trans *trans, va_list *argptr)
{
enum libipm_status rv = E_LI_SUCCESS;
struct stream *s = trans->out_s;
if (!s_check_rem_out(s, 1 + 4))
{
log_append_error(trans, not_enough_output_msg, c);
rv = E_LI_BUFFER_OVERFLOW;
}
else
{
/* If int is bigger than 4 bytes, the argument will be
* promoted to 'int' rather than 'int32_t'/'uint32_t',
* and we will need to check the specified value is in range.
*/
#if SIZEOF_INT > 4
int tmp = va_arg(*argptr, int);
if ((c == 'i' && (tmp < -0x80000000 || tmp > 0x7fffffff)) ||
(c == 'u' && (tmp < 0 || tmp > 0xffffffff)))
{
log_append_error(trans, bad_value_msg, c, tmp);
rv = E_LI_BAD_VALUE;
}
else
{
out_uint8(s, c);
out_uint32_le(s, tmp);
}
#else
uint32_t tmp = va_arg(*argptr, uint32_t);
out_uint8(s, c);
out_uint32_le(s, tmp);
#endif
}
return rv;
}
/**************************************************************************//**
* Add a 64-bit integer to the output stream
*
* @param c Type letter which triggered the call
* @param trans libipm transport
* @param argptr Pointer to value in argument stack
* @return != 0 for error
*/
static enum libipm_status
append_int64_type(char c, struct trans *trans, va_list *argptr)
{
enum libipm_status rv = E_LI_SUCCESS;
struct stream *s = trans->out_s;
if (!s_check_rem_out(s, 1 + 8))
{
log_append_error(trans, not_enough_output_msg, c);
rv = E_LI_BUFFER_OVERFLOW;
}
else
{
uint64_t tmp = va_arg(*argptr, uint64_t);
out_uint8(s, c);
out_uint64_le(s, tmp);
}
return rv;
}
/**************************************************************************//**
* Add a terminated string to the output stream
*
* @param c Type letter which triggered the call
* @param trans libipm transport
* @param argptr Pointer to value in argument stack (promoted to int)
* @return != 0 for error
*
* NULL pointers are not allowed for the string.
*/
static enum libipm_status
append_char_ptr_type(char c, struct trans *trans, va_list *argptr)
{
enum libipm_status rv = E_LI_SUCCESS;
struct stream *s = trans->out_s;
const char *str = va_arg(*argptr, const char *);
if (str == NULL)
{
log_append_error(trans, "String cannot be NULL");
rv = E_LI_PROGRAM_ERROR;
}
else
{
unsigned int len = g_strlen(str);
if ((len > (LIBIPM_MAX_MSG_SIZE - HEADER_SIZE - 1)) ||
(!s_check_rem_out(s, 1 + 1 + len)))
{
log_append_error(trans,
"Not enough space in output buffer for "
"'%c'[len=%u]", c, len);
rv = E_LI_BUFFER_OVERFLOW;
}
else
{
out_uint8(s, c);
out_uint8p(s, str, len + 1);
}
}
return rv;
}
/**************************************************************************//**
* Add a file descriptor to the output stream
*
* @param c Type letter which triggered the call
* @param trans libipm transport
* @param argptr Pointer to value in argument stack (promoted to int)
* @return != 0 for error
*/
static enum libipm_status
append_fd_type(char c, va_list *argptr, struct trans *trans)
{
enum libipm_status rv = E_LI_SUCCESS;
struct stream *s = trans->out_s;
struct libipm_priv *priv = (struct libipm_priv *)trans->extra_data;
int fd = va_arg(*argptr, int);
if (fd < 0)
{
log_append_error(trans, "File descriptor cannot be < 0");
rv = E_LI_PROGRAM_ERROR;
}
else if (!s_check_rem_out(s, 1))
{
log_append_error(trans,
"Not enough space in output buffer for '%c'", c);
rv = E_LI_BUFFER_OVERFLOW;
}
else if (priv->out_fd_count >= MAX_FD_PER_MSG)
{
log_append_error(trans,
"Too many file descriptors for '%c'", c);
rv = E_LI_TOO_MANY_FDS;
}
else
{
out_uint8(s, c);
priv->out_fds[priv->out_fd_count++] = fd;
}
return rv;
}
/**************************************************************************//**
* Append a fixed size block to the output stream
*
* @param c Type letter which triggered the call
* @param trans libipm transport
* @param argptr argptr to pointer to block descriptor
* @return != 0 for error
*/
static enum libipm_status
append_fsb_type(char c, struct trans *trans, va_list *argptr)
{
enum libipm_status rv = E_LI_SUCCESS;
struct stream *s = trans->out_s;
const struct libipm_fsb *fsb = va_arg(*argptr, const struct libipm_fsb *);
if (fsb == NULL || fsb->data == NULL)
{
log_append_error(trans, "Malformed descriptor for '%c'", c);
rv = E_LI_PROGRAM_ERROR;
}
else
{
unsigned int len = fsb->datalen;
if ((len > (LIBIPM_MAX_MSG_SIZE - HEADER_SIZE - 2)) ||
(!s_check_rem_out(s, 1 + 2 + len)))
{
log_append_error(trans, "Not enough space in output buffer"
" for '%c'[len=%u]", c, len);
rv = E_LI_BUFFER_OVERFLOW;
}
else
{
out_uint8(s, c);
out_uint16_le(s, len);
out_uint8a(s, fsb->data, len);
}
}
return rv;
}
/**************************************************************************//**
* Local function to append data to the output stream
*
* @param trans libipm transport
* @param format type-system compatible string
* @param argptr Variables containing data to append
* @pre - trans->priv has been checked to be non-NULL
* @return != 0 for error
*/
static enum libipm_status
libipm_msg_out_appendv(struct trans *trans, const char *format, va_list *argptr)
{
enum libipm_status rv = E_LI_SUCCESS;
struct libipm_priv *priv = (struct libipm_priv *)trans->extra_data;
const char *cp;
if (format != NULL)
{
for (cp = format; rv == 0 && *cp != '\0' ; ++cp)
{
char c = *cp;
++priv->out_param_count; /* Count the parameter */
if (g_strchr(libipm_valid_type_chars, c) == NULL)
{
log_append_error(trans,
"Type code '%c' is not supported", c);
rv = E_LI_UNSUPPORTED_TYPE;
break;
}
switch (c)
{
case 'y':
rv = append_int8_type(c, trans, argptr);
break;
case 'b':
rv = append_bool_type(c, trans, argptr);
break;
case 'n':
case 'q':
rv = append_int16_type(c, trans, argptr);
break;
case 'i':
case 'u':
rv = append_int32_type(c, trans, argptr);
break;
case 'x':
case 't':
rv = append_int64_type(c, trans, argptr);
break;
case 's':
rv = append_char_ptr_type(c, trans, argptr);
break;
case 'h':
rv = append_fd_type(c, argptr, trans);
break;
case 'B':
rv = append_fsb_type(c, trans, argptr);
break;
default:
log_append_error(trans,
"Reserved type code '%c' "
"is unimplemented", c);
rv = E_LI_UNIMPLEMENTED_TYPE;
break;
}
}
}
return rv;
}
/**************************************************************************//**
* Prepare the transport to build an output message
* @param trans libipm trans
* @param msgno Number of message
* @return != 0 for error
*/
static void
init_output_buffer(struct trans *trans, unsigned short msgno)
{
struct stream *s = trans->out_s;
struct libipm_priv *priv = (struct libipm_priv *)trans->extra_data;
init_stream(s, LIBIPM_MAX_MSG_SIZE);
/* Leave space for header */
s_push_layer(s, iso_hdr, HEADER_SIZE);
priv->out_msgno = msgno;
priv->out_param_count = 0;
priv->out_fd_count = 0;
}
/*****************************************************************************/
enum libipm_status
libipm_msg_out_init(struct trans *trans, unsigned short msgno,
const char *format, ...)
{
enum libipm_status rv;
struct libipm_priv *priv = (struct libipm_priv *)trans->extra_data;
if (priv == NULL)
{
LOG_DEVEL(LOG_LEVEL_ERROR, "uninitialised transport");
rv = E_LI_PROGRAM_ERROR;
}
else
{
va_list argptr;
init_output_buffer(trans, msgno);
va_start(argptr, format);
rv = libipm_msg_out_appendv(trans, format, &argptr);
va_end(argptr);
}
return rv;
}
/*****************************************************************************/
enum libipm_status
libipm_msg_out_append(struct trans *trans, const char *format, ...)
{
enum libipm_status rv;
struct libipm_priv *priv = (struct libipm_priv *)trans->extra_data;
if (priv == NULL)
{
LOG_DEVEL(LOG_LEVEL_ERROR, "uninitialised transport");
rv = E_LI_PROGRAM_ERROR;
}
else
{
va_list argptr;
va_start(argptr, format);
rv = libipm_msg_out_appendv(trans, format, &argptr);
va_end(argptr);
}
return rv;
}
/*****************************************************************************/
void
libipm_msg_out_mark_end(struct trans *trans)
{
struct libipm_priv *priv = (struct libipm_priv *)trans->extra_data;
if (priv == NULL)
{
LOG_DEVEL(LOG_LEVEL_ERROR, "uninitialised transport");
}
else
{
struct stream *s = trans->out_s;
s_mark_end(s);
s_pop_layer(s, iso_hdr);
/* Write the message header */
out_uint16_le(s, LIBIPM_VERSION);
out_uint16_le(s, s->end - s->data);
out_uint16_le(s, priv->facility);
out_uint16_le(s, priv->out_msgno);
out_uint32_le(s, 0); /* Reserved */
/* Move the output pointer back to the end so another
* append works, and so libipm_msg_out_erase() knows
* exactly what to do */
s->p = s->end;
}
}
/*****************************************************************************/
enum libipm_status
libipm_msg_out_simple_send(struct trans *trans, unsigned short msgno,
const char *format, ...)
{
enum libipm_status rv;
struct libipm_priv *priv = (struct libipm_priv *)trans->extra_data;
if (priv == NULL)
{
LOG_DEVEL(LOG_LEVEL_ERROR, "uninitialised transport");
rv = E_LI_PROGRAM_ERROR;
}
else
{
va_list argptr;
va_start(argptr, format);
init_output_buffer(trans, msgno);
rv = libipm_msg_out_appendv(trans, format, &argptr);
if (rv == E_LI_SUCCESS)
{
libipm_msg_out_mark_end(trans);
if (trans_force_write(trans) != 0)
{
rv = E_LI_TRANSPORT_ERROR;
}
}
va_end(argptr);
}
return rv;
}
/*****************************************************************************/
void
libipm_msg_out_erase(struct trans *trans)
{
struct stream *s = trans->out_s;
if (s->size > 0 && s->data != 0)
{
g_memset(s->data, '\0', s->p - s->data);
}
}