NetBSD-5.0.2/dist/dhcp/dst/dst_support.c
static const char rcsid[] = "$Header: /cvsroot/src/dist/dhcp/dst/dst_support.c,v 1.3 2005/08/11 17:13:21 drochner Exp $";
/*
* Portions Copyright (c) 1995-1998 by Trusted Information Systems, Inc.
*
* Permission to use, copy modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND TRUSTED INFORMATION SYSTEMS
* DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
* TRUSTED INFORMATION SYSTEMS BE LIABLE FOR ANY SPECIAL, DIRECT,
* INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
* FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
* NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
* WITH THE USE OR PERFORMANCE OF THE SOFTWARE.
*/
#include <stdio.h>
#include <unistd.h>
#include <memory.h>
#include <string.h>
#include <errno.h>
#include <sys/stat.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include "minires/minires.h"
#include "arpa/nameser.h"
#include "dst_internal.h"
/*
* dst_s_conv_bignum_u8_to_b64
* This function converts binary data stored as a u_char[] to a
* base-64 string. Leading zeroes are discarded. If a header is
* supplied, it is prefixed to the input prior to encoding. The
* output is \n\0 terminated (the \0 is not included in output length).
* Parameters
* out_buf binary data to convert
* header character string to prefix to the output (label)
* bin_data binary data
* bin_len size of binary data
* Return
* -1 not enough space in output work area
* 0 no output
* >0 number of bytes written to output work area
*/
int
dst_s_conv_bignum_u8_to_b64(char *out_buf, const unsigned out_len,
const char *header, const u_char *bin_data,
const unsigned bin_len)
{
const u_char *bp = bin_data;
char *op = out_buf;
unsigned lenh = 0, len64 = 0;
unsigned local_in_len = bin_len;
unsigned local_out_len = out_len;
if (bin_data == NULL) /* no data no */
return (0);
if (out_buf == NULL || out_len <= 0) /* no output_work area */
return (-1);
/* suppress leading \0 */
for (; (*bp == 0x0) && (local_in_len > 0); local_in_len--)
bp++;
if (header) { /* add header to output string */
lenh = strlen(header);
if (lenh < out_len)
memcpy(op, header, lenh);
else
return (-1);
local_out_len -= lenh;
op += lenh;
}
len64 = b64_ntop(bp, local_in_len, op, local_out_len - 2);
if (len64 < 0)
return (-1);
op += len64++;
*(op++) = '\n'; /* put CR in the output */
*op = '\0'; /* make sure output is 0 terminated */
return (lenh + len64);
}
/*
* dst_s_verify_str()
* Validate that the input string(*str) is at the head of the input
* buffer(**buf). If so, move the buffer head pointer (*buf) to
* the first byte of data following the string(*str).
* Parameters
* buf Input buffer.
* str Input string.
* Return
* 0 *str is not the head of **buff
* 1 *str is the head of **buff, *buf is is advanced to
* the tail of **buf.
*/
int
dst_s_verify_str(const char **buf, const char *str)
{
unsigned b, s;
if (*buf == NULL) /* error checks */
return (0);
if (str == NULL || *str == '\0')
return (1);
b = strlen(*buf); /* get length of strings */
s = strlen(str);
if (s > b || strncmp(*buf, str, s)) /* check if same */
return (0); /* not a match */
(*buf) += s; /* advance pointer */
return (1);
}
/*
* dst_s_conv_bignum_b64_to_u8
* Read a line of base-64 encoded string from the input buffer,
* convert it to binary, and store it in an output area. The
* input buffer is read until reaching a newline marker or the
* end of the buffer. The binary data is stored in the last X
* number of bytes of the output area where X is the size of the
* binary output. If the operation is successful, the input buffer
* pointer is advanced. This procedure does not do network to host
* byte order conversion.
* Parameters
* buf Pointer to encoded input string. Pointer is updated if
* function is successfull.
* loc Output area.
* loclen Size in bytes of output area.
* Return
* >0 Return = number of bytes of binary data stored in loc.
* 0 Failure.
*/
int
dst_s_conv_bignum_b64_to_u8(const char **buf,
u_char *loc, const unsigned loclen)
{
unsigned blen;
char *bp;
u_char bstr[RAW_KEY_SIZE];
if (buf == NULL || *buf == NULL) { /* error checks */
EREPORT(("dst_s_conv_bignum_b64_to_u8: null input buffer.\n"));
return (0);
}
bp = strchr(*buf, '\n'); /* find length of input line */
if (bp != NULL)
*bp = (u_char) NULL;
blen = b64_pton(*buf, bstr, sizeof(bstr));
if (blen <= 0) {
EREPORT(("dst_s_conv_bignum_b64_to_u8: decoded value is null.\n"));
return (0);
}
else if (loclen < blen) {
EREPORT(("dst_s_conv_bignum_b64_to_u8: decoded value is longer than output buffer.\n"));
return (0);
}
if (bp)
*buf = bp; /* advancing buffer past \n */
memset(loc, 0, loclen - blen); /* clearing unused output area */
memcpy(loc + loclen - blen, bstr, blen); /* write last blen bytes */
return (blen);
}
/*
* dst_s_calculate_bits
* Given a binary number represented in a u_char[], determine
* the number of significant bits used.
* Parameters
* str An input character string containing a binary number.
* max_bits The maximum possible significant bits.
* Return
* N The number of significant bits in str.
*/
int
dst_s_calculate_bits(const u_char *str, const int max_bits)
{
const u_char *p = str;
u_char i, j = 0x80;
int bits;
for (bits = max_bits; *p == 0x00 && bits > 0; p++)
bits -= 8;
for (i = *p; (i & j) != j; j >>= 1)
bits--;
return (bits);
}
/*
* calculates a checksum used in kmt for a id.
* takes an array of bytes and a length.
* returns a 16 bit checksum.
*/
u_int16_t
dst_s_id_calc(const u_char *key, const unsigned keysize)
{
u_int32_t ac;
const u_char *kp = key;
unsigned size = keysize;
if (!key)
return 0;
for (ac = 0; size > 1; size -= 2, kp += 2)
ac += ((*kp) << 8) + *(kp + 1);
if (size > 0)
ac += ((*kp) << 8);
ac += (ac >> 16) & 0xffff;
return (ac & 0xffff);
}
/*
* dst_s_dns_key_id() Function to calculated DNSSEC footprint from KEY reocrd
* rdata (all of record)
* Input:
* dns_key_rdata: the raw data in wire format
* rdata_len: the size of the input data
* Output:
* the key footprint/id calcuated from the key data
*/
u_int16_t
dst_s_dns_key_id(const u_char *dns_key_rdata, const unsigned rdata_len)
{
unsigned key_data = 4;
if (!dns_key_rdata || (rdata_len < key_data))
return 0;
/* check the extended parameters bit in the DNS Key RR flags */
if (dst_s_get_int16(dns_key_rdata) & DST_EXTEND_FLAG)
key_data += 2;
/* compute id */
if (dns_key_rdata[3] == KEY_RSA) /* Algorithm RSA */
return dst_s_get_int16((const u_char *)
&dns_key_rdata[rdata_len - 3]);
else
/* compute a checksum on the key part of the key rr */
return dst_s_id_calc(&dns_key_rdata[key_data],
(rdata_len - key_data));
}
/*
* dst_s_get_int16
* This routine extracts a 16 bit integer from a two byte character
* string. The character string is assumed to be in network byte
* order and may be unaligned. The number returned is in host order.
* Parameter
* buf A two byte character string.
* Return
* The converted integer value.
*/
u_int16_t
dst_s_get_int16(const u_char *buf)
{
register u_int16_t a = 0;
a = ((u_int16_t)(buf[0] << 8)) | ((u_int16_t)(buf[1]));
return (a);
}
/*
* dst_s_get_int32
* This routine extracts a 32 bit integer from a four byte character
* string. The character string is assumed to be in network byte
* order and may be unaligned. The number returned is in host order.
* Parameter
* buf A four byte character string.
* Return
* The converted integer value.
*/
u_int32_t
dst_s_get_int32(const u_char *buf)
{
register u_int32_t a = 0;
a = ((u_int32_t)(buf[0] << 24)) | ((u_int32_t)(buf[1] << 16)) |
((u_int32_t)(buf[2] << 8)) | ((u_int32_t)(buf[3]));
return (a);
}
/*
* dst_s_put_int16
* Take a 16 bit integer and store the value in a two byte
* character string. The integer is assumed to be in network
* order and the string is returned in host order.
*
* Parameters
* buf Storage for a two byte character string.
* val 16 bit integer.
*/
void
dst_s_put_int16(u_int8_t *buf, const u_int16_t val)
{
buf[0] = (u_int8_t)(val >> 8);
buf[1] = (u_int8_t)(val);
}
/*
* dst_s_put_int32
* Take a 32 bit integer and store the value in a four byte
* character string. The integer is assumed to be in network
* order and the string is returned in host order.
*
* Parameters
* buf Storage for a four byte character string.
* val 32 bit integer.
*/
void
dst_s_put_int32(u_int8_t *buf, const u_int32_t val)
{
buf[0] = (u_int8_t)(val >> 24);
buf[1] = (u_int8_t)(val >> 16);
buf[2] = (u_int8_t)(val >> 8);
buf[3] = (u_int8_t)(val);
}
/*
* dst_s_filename_length
*
* This function returns the number of bytes needed to hold the
* filename for a key file. '/', '\' and ':' are not allowed.
* form: K<keyname>+<alg>+<id>.<suffix>
*
* Returns 0 if the filename would contain either '\', '/' or ':'
*/
size_t
dst_s_filename_length(const char *name, const char *suffix)
{
if (name == NULL)
return (0);
if (strrchr(name, '\\'))
return (0);
if (strrchr(name, '/'))
return (0);
if (strrchr(name, ':'))
return (0);
if (suffix == NULL)
return (0);
if (strrchr(suffix, '\\'))
return (0);
if (strrchr(suffix, '/'))
return (0);
if (strrchr(suffix, ':'))
return (0);
return (1 + strlen(name) + 6 + strlen(suffix));
}
/*
* dst_s_build_filename ()
* Builds a key filename from the key name, it's id, and a
* suffix. '\', '/' and ':' are not allowed. fA filename is of the
* form: K<keyname><id>.<suffix>
* form: K<keyname>+<alg>+<id>.<suffix>
*
* Returns -1 if the conversion fails:
* if the filename would be too long for space allotted
* if the filename would contain a '\', '/' or ':'
* Returns 0 on success
*/
int
dst_s_build_filename(char *filename, const char *name, unsigned id,
int alg, const char *suffix, size_t filename_length)
{
unsigned my_id;
if (filename == NULL)
return (-1);
memset(filename, 0, filename_length);
if (name == NULL)
return (-1);
if (suffix == NULL)
return (-1);
if (filename_length < 1 + strlen(name) + 4 + 6 + 1 + strlen(suffix))
return (-1);
my_id = id;
sprintf(filename, "K%s+%03d+%05d.%s", name, alg, my_id,
(const char *) suffix);
if (strrchr(filename, '/'))
return (-1);
if (strrchr(filename, '\\'))
return (-1);
if (strrchr(filename, ':'))
return (-1);
return (0);
}
/*
* dst_s_fopen ()
* Open a file in the dst_path directory. If perm is specified, the
* file is checked for existence first, and not opened if it exists.
* Parameters
* filename File to open
* mode Mode to open the file (passed directly to fopen)
* perm File permission, if creating a new file.
* Returns
* NULL Failure
* NON-NULL (FILE *) of opened file.
*/
FILE *
dst_s_fopen(const char *filename, const char *mode, unsigned perm)
{
FILE *fp;
char pathname[PATH_MAX];
unsigned plen = sizeof(pathname);
if (*dst_path != '\0') {
strcpy(pathname, dst_path);
plen -= strlen(pathname);
}
else
pathname[0] = '\0';
if (plen > strlen(filename))
strncpy(&pathname[PATH_MAX - plen], filename, plen-1);
else
return (NULL);
fp = fopen(pathname, mode);
if (perm)
chmod(pathname, perm);
return (fp);
}
#if 0
void
dst_s_dump(const int mode, const u_char *data, const int size,
const char *msg)
{
if (size > 0) {
#ifdef LONG_TEST
static u_char scratch[1000];
int n ;
n = b64_ntop(data, scratch, size, sizeof(scratch));
printf("%s: %x %d %s\n", msg, mode, n, scratch);
#else
printf("%s,%x %d\n", msg, mode, size);
#endif
}
}
#endif