send_token() and recv_token()
These functions send and receive data between the client and the server. (In a multiprocess application they could do the same between processes.) They are slightly misnamed, since they send and receive messages as well as tokens. They are oblivious to the
content they handle.
send_token()
This function sends a token or message.
Example A-18 send_token()
/*
* Function: send_token
*
* Purpose: Writes a token to a file descriptor.
*
* Arguments:
*
* s (r) an open file descriptor
* tok (r) the token to write
*
* Returns: 0 on success, -1 on failure
*
* Effects:
*
* send_token writes the token length (as a network long) and then the
* token data to the file descriptor s. It returns 0 on success, and
* -1 if an error occurs or if it could not write all the data.
*/
int send_token(s, tok)
int s;
gss_buffer_t tok;
{
int len, ret;
len = htonl((OM_uint32)tok->length);
ret = write_all(s, (char *) &len, sizeof(int));
if (ret < 0) {
perror("sending token length");
return -1;
} else if (ret != 4) {
if (display_file)
fprintf(display_file,
"sending token length: %d of %d bytes written\n",
ret, 4);
return -1;
}
ret = write_all(s, tok->value, (OM_uint32)tok->length);
if (ret < 0) {
perror("sending token data");
return -1;
} else if (ret != tok->length) {
if (display_file)
fprintf(display_file,
"sending token data: %d of %d bytes written\n",
ret, tok->length);
return -1;
}
return 0;
}
|
recv_token()
This function receives a token or message.
Example A-19 recv_token()
/*
* Function: recv_token
*
* Purpose: Reads a token from a file descriptor.
*
* Arguments:
*
* s (r) an open file descriptor
* tok (w) the read token
*
* Returns: 0 on success, -1 on failure
*
* Effects:
*
* recv_token reads the token length (as a network long), allocates
* memory to hold the data, and then reads the token data from the
* file descriptor s. It blocks to read the length and data, if
* necessary. On a successful return, the token should be freed with
* gss_release_buffer. It returns 0 on success, and -1 if an error
* occurs or if it could not read all the data.
*/
int recv_token(s, tok)
int s;
gss_buffer_t tok;
{
int ret, len;
ret = read_all(s, (char *) &len, sizeof(int));
if (ret < 0) {
perror("reading token length");
return -1;
} else if (ret != 4) {
if (display_file)
fprintf(display_file,
"reading token length: %d of %d bytes read\n",
ret, 4);
return -1;
}
tok->length = ntohl(len);
tok->value = (char *) malloc(tok->length);
if (tok->value == NULL) {
if (display_file)
fprintf(display_file,
"Out of memory allocating token data\n");
return -1;
}
ret = read_all(s, (char *) tok->value, (OM_uint32)tok->length);
if (ret < 0) {
perror("reading token data");
free(tok->value);
return -1;
} else if (ret != tok->length) {
fprintf(stderr, "sending token data: %d of %d bytes written\n",
ret, tok->length);
free(tok->value);
return -1;
}
return 0;
}
|
