ajp_msg.c

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/* Copyright 1999-2004 The Apache Software Foundation
 *
 * 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.
 */

#include "ajp.h"


static char *hex_table = "0123456789ABCDEF";

/**
 * Dump up to the first 1024 bytes on an AJP Message
 *
 * @param msg       AJP Message to dump
 * @param err       error string to display
 * @return          APR_SUCCESS or error
 */
apr_status_t ajp_msg_dump(ajp_msg_t *msg, char *err)
{
    apr_size_t  i, j;
    char        line[80];
    char        *current;
    apr_byte_t  x;
    apr_size_t  len = msg->len;

    /* Display only first 1024 bytes */
    if (len > 1024)
        len = 1024;

    ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, NULL,
                  "ajp_msg_dump(): %s pos=%d len=%d max=%d",
                  err, msg->pos, msg->len, AJP_MSG_BUFFER_SZ);

    for (i = 0; i < len; i += 16) {
        current = line;

        for (j = 0; j < 16; j++) {
             x = msg->buf[i + j];

            *current++ = hex_table[x >> 4];
            *current++ = hex_table[x & 0x0f];
            *current++ = ' ';
        }
        *current++ = ' ';
        *current++ = '-';
        *current++ = ' ';
        for (j = 0; j < 16; j++) {
            x = msg->buf[i + j];

            if (x > 0x20 && x < 0x7F) {
                *current++ = x;
            }
            else {
                *current++ = '.';
            }
        }

        *current++ = '\0';

        ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, NULL,
                      "ajp_msg_dump(): %.4x    %s",
                      i, line);
    }
    
    return APR_SUCCESS;
}


/**
 * Check a new AJP Message by looking at signature and return its size
 *
 * @param msg       AJP Message to check
 * @param len       Pointer to returned len
 * @return          APR_SUCCESS or error
 */
apr_status_t ajp_msg_check_header(ajp_msg_t *msg, apr_size_t *len)
{
    apr_byte_t *head = msg->buf;
    apr_size_t msglen;

    if (!((head[0] == 0x41 && head[1] == 0x42) ||
          (head[0] == 0x12 && head[1] == 0x34))) {

        ap_log_error(APLOG_MARK, APLOG_ERR, 0, NULL,
                      "ajp_check_msg_header() got bad signature %x%x",
                      head[0], head[1]);

        return AJP_EBAD_SIGNATURE;
    }

    msglen  = ((head[2] & 0xff) << 8);
    msglen += (head[3] & 0xFF);

    if (msglen > AJP_MSG_BUFFER_SZ) {
        ap_log_error(APLOG_MARK, APLOG_ERR, 0, NULL,
                      "ajp_check_msg_header() incoming message is too big %d, max is %d",
                      msglen, AJP_MSG_BUFFER_SZ);
        return AJP_ETOBIG;
    }

    msg->len = msglen + AJP_HEADER_LEN;
    msg->pos = AJP_HEADER_LEN;
    *len     = msglen;
    
    return APR_SUCCESS;
}

/**
 * Reset an AJP Message
 *
 * @param msg       AJP Message to reset
 * @return          APR_SUCCESS or error
 */
apr_status_t ajp_msg_reset(ajp_msg_t *msg)
{
    msg->len = AJP_HEADER_LEN;
    msg->pos = AJP_HEADER_LEN;
    
    return APR_SUCCESS;
}

/**
 * Mark the end of an AJP Message
 *
 * @param msg       AJP Message to end
 * @return          APR_SUCCESS or error
 */
apr_status_t ajp_msg_end(ajp_msg_t *msg)
{
    apr_size_t len = msg->len - AJP_HEADER_LEN;

    if (msg->server_side) {
        msg->buf[0] = 0x41;
        msg->buf[1] = 0x42;
    }
    else {
        msg->buf[0] = 0x12;
        msg->buf[1] = 0x34;
    }

    msg->buf[2] = (apr_byte_t)((len >> 8) & 0xFF);
    msg->buf[3] = (apr_byte_t)(len & 0xFF);
    
    return APR_SUCCESS;
}

/**
 * Add an unsigned 32bits value to AJP Message
 *
 * @param msg       AJP Message to get value from
 * @param value     value to add to AJP Message
 * @return          APR_SUCCESS or error
 */
apr_status_t ajp_msg_append_uint32(ajp_msg_t *msg, apr_uint32_t value)
{
    apr_size_t len = msg->len;

    if ((len + 4) > AJP_MSG_BUFFER_SZ) {
        ap_log_error(APLOG_MARK, APLOG_ERR, 0, NULL,
                      "ajp_msg_append_uint32(): BufferOverflowException %d %d",
                      msg->pos, msg->len);
        return AJP_EOVERFLOW;
    }

    msg->buf[len]     = (apr_byte_t)((value >> 24) & 0xFF);
    msg->buf[len + 1] = (apr_byte_t)((value >> 16) & 0xFF);
    msg->buf[len + 2] = (apr_byte_t)((value >> 8) & 0xFF);
    msg->buf[len + 3] = (apr_byte_t)(value & 0xFF);

    msg->len += 4;

    return APR_SUCCESS;
}

/**
 * Add an unsigned 16bits value to AJP Message
 *
 * @param msg       AJP Message to get value from
 * @param value     value to add to AJP Message
 * @return          APR_SUCCESS or error
 */
apr_status_t ajp_msg_append_uint16(ajp_msg_t *msg, apr_uint16_t value)
{
    apr_size_t len = msg->len;

    if ((len + 2) > AJP_MSG_BUFFER_SZ) {
        ap_log_error(APLOG_MARK, APLOG_ERR, 0, NULL,
                      "ajp_msg_append_uint16(): BufferOverflowException %d %d",
                      msg->pos, msg->len);
        return AJP_EOVERFLOW;
    }

    msg->buf[len]     = (apr_byte_t)((value >> 8) & 0xFF);
    msg->buf[len + 1] = (apr_byte_t)(value & 0xFF);

    msg->len += 2;

    return APR_SUCCESS;
}

/**
 * Add an unsigned 8bits value to AJP Message
 *
 * @param msg       AJP Message to get value from
 * @param value     value to add to AJP Message
 * @return          APR_SUCCESS or error
 */
apr_status_t ajp_msg_append_uint8(ajp_msg_t *msg, apr_byte_t value)
{
    apr_size_t len = msg->len;

    if ((len + 1) > AJP_MSG_BUFFER_SZ) {
        ap_log_error(APLOG_MARK, APLOG_ERR, 0, NULL,
                      "ajp_msg_append_uint8(): BufferOverflowException %d %d",
                      msg->pos, msg->len);
        return AJP_EOVERFLOW;
    }

    msg->buf[len] = value;
    msg->len += 1;

    return APR_SUCCESS;
}

/**
 *  Add a String in AJP message, and transform the String in ASCII 
 *  if convert is set and we're on an EBCDIC machine    
 *
 * @param msg       AJP Message to get value from
 * @param value     Pointer to String
 * @param convert   When set told to convert String to ASCII
 * @return          APR_SUCCESS or error
 */
apr_status_t ajp_msg_append_string_ex(ajp_msg_t *msg, const char *value,
                                      int convert)
{
    size_t len;

    if (value == NULL) {
        return(ajp_msg_append_uint16(msg, 0xFFFF));
    }

    len = strlen(value);
    if ((msg->len + len + 2) > AJP_MSG_BUFFER_SZ) {
        ap_log_error(APLOG_MARK, APLOG_ERR, 0, NULL,
            "ajp_msg_append_cvt_string(): BufferOverflowException %d %d",
            msg->pos, msg->len);
        return AJP_EOVERFLOW;
    }

    /* ignore error - we checked once */
    ajp_msg_append_uint16(msg, (apr_uint16_t)len);

    /* We checked for space !!  */
    memcpy(msg->buf + msg->len, value, len + 1); /* including \0 */

    if (convert)   /* convert from EBCDIC if needed */
        ajp_xlate_to_ascii((char *)msg->buf + msg->len, len + 1);

    msg->len += len + 1;

    return APR_SUCCESS;
}

/**
 * Add a Byte array to AJP Message
 *
 * @param msg       AJP Message to get value from
 * @param value     Pointer to Byte array
 * @param valuelen  Byte array len
 * @return          APR_SUCCESS or error
 */
apr_status_t ajp_msg_append_bytes(ajp_msg_t *msg, const apr_byte_t *value,
                                  apr_size_t valuelen)
{
    if (! valuelen) {
        return APR_SUCCESS; /* Shouldn't we indicate an error ? */
    }

    if ((msg->len + valuelen) > AJP_MSG_BUFFER_SZ) {
        ap_log_error(APLOG_MARK, APLOG_ERR, 0, NULL,
                      "ajp_msg_append_bytes(): BufferOverflowException %d %d",
                      msg->pos, msg->len);
        return AJP_EOVERFLOW;
    }

    /* We checked for space !!  */
    memcpy(msg->buf + msg->len, value, valuelen);
    msg->len += valuelen;

    return APR_SUCCESS;
}

/**