/**
+-5-+ +---+
v | v |
+------+ +------+ +------+ +------+ +------+
| 0 |--$--> |1-hdr |--alnum--> |2-data|----\r-->| 6-LF |---\n--->| done |--> 0
+------+ +------+ +------+ +------+ +------+
| ^
* +--------\r-------+
V |
+------+ +------+ +------+
|3-cks |--xdigit-->|4-cks |-xdigit->| 5-CR |
+------+ +------+ +------+
return to start conditions:
1. buffer overflow
2. invalid character for state
checksum calculation
two hex digits represent the XOR of all characters between, but not
including, the "$" and "*". A checksum is required on some
sentences.
*/
int nmeap_parse(nmeap_context_t *context,char ch)
{
int status = 0;
/* check for input buffer overrun first to avoid duplicating code in the
individual states
*/
if ((size_t)context->input_count >= (sizeof(context->input)-1)) {
/* input buffer overrun, restart state machine */
context->input_state = 0;
/* reset input count */
context->input_count = 0;
}
/* store the byte */
context->input[context->input_count] = ch;
/* next buffer position */
context->input_count++;
/* run it through the lexical scanner */
switch(context->input_state) {
/* LOOKING FOR $ */
case 0:
if (ch == '$') {
/*look for id */
context->input_state = 1;
context->ccks = 0;
context->icks = 0;
}
else {
/* header error, start over */
context->err_hdr++;
context->input_state = 0;
context->input_count = 0;
}
break;
/* LOOKING FOR 5 CHARACTER SENTENCE ID */
case 1:
/* allow numbers even though it isn't usually done */
/* a proprietary id might have a numeral */
if (isalnum((unsigned char)ch)) {
/* store name separately */
context->input_name[context->input_count - 2] = ch;
/* checksum */
context->ccks ^= ch;
/* end of header? */
if (context->input_count >= 6) {
/* yes, get body */
context->input_state = 2;
}
}
else {
/* bad character, start over */
context->err_id++;
context->input_state = 0;
context->input_count = 0;
}
break;
/* LOOKING FOR CR OR CHECKSUM INDICATOR */
case 2:
if (ch == '*') {
/* this sentence has a checksum */
context->input_state = 3;
}
else if (ch == '\r') {
/* carriage return, no checksum, force a match */
context->icks = 0;
context->ccks = 0;
context->input_state = 6;
}
else {
/* continue accumulating data */
/* checksum */
context->ccks ^= ch;
}
break;
/* LOOKING FOR FIRST CHECKSUM CHARACTER */
case 3:
/* must be upper case hex digit */
if (isxdigit((unsigned char)ch) && (ch <= 'F')) {
/* got first checksum byte */
context->input_state = 4;
context->icks = HEXTOBIN(ch) << 4;
}
else {
/* input error, restart */
context->err_cks++;
context->input_state = 0;
context->input_count = 0;
}
break;
/* LOOKING FOR SECOND CHECKSUM CHARACTER */
case 4:
/* must be upper case hex digit */
if (isxdigit((unsigned char)ch) && (ch <= 'F')) {
/* got second checksum byte */
context->input_state = 5;
context->icks += HEXTOBIN(ch);
}
else {
/* input error, restart */
context->err_cks++;
context->input_state = 0;
context->input_count = 0;
}
break;
/* LOOKING FOR CR */
case 5:
if (ch == '\r') {
/* carriage return */
context->input_state = 6;
}
else {
/* input error, restart */
context->err_crl++;
context->input_state = 0;
context->input_count = 0;
}
break;
/* LOOKING FOR LINE FEED */
case 6:
if (ch == '\n') {
/* linefeed, line complete */
/* delimit buffer */
context->input[context->input_count] = 0;
/* if the checksums match, process the sentence */
if (context->ccks == context->icks) {
/* process */
status = nmeap_process(context);
/* count good messages */
context->msgs++;
}
else {
/* count checksum errors */
context->err_cks++;
}
/* restart next time */
context->input_state = 0;
context->input_count = 0;
}
else {
/* input error, restart */
context->err_crl++;
context->input_state = 0;
context->input_count = 0;
}
break;
default:
context->err_unk++;
context->input_state = 0;
break;
}
return status;
}
void
import_ownertrust (ctrl_t ctrl, const char *fname )
{
estream_t fp;
int is_stdin=0;
char line[256];
char *p;
size_t n, fprlen;
unsigned int otrust;
byte fpr[MAX_FINGERPRINT_LEN];
int any = 0;
int rc;
init_trustdb (ctrl, 0);
if( iobuf_is_pipe_filename (fname) ) {
fp = es_stdin;
fname = "[stdin]";
is_stdin = 1;
}
else if( !(fp = es_fopen( fname, "r" )) ) {
log_error ( _("can't open '%s': %s\n"), fname, strerror(errno) );
return;
}
if (is_secured_file (es_fileno (fp)))
{
es_fclose (fp);
gpg_err_set_errno (EPERM);
log_error (_("can't open '%s': %s\n"), fname, strerror(errno) );
return;
}
while (es_fgets (line, DIM(line)-1, fp)) {
TRUSTREC rec;
if( !*line || *line == '#' )
continue;
n = strlen(line);
if( line[n-1] != '\n' ) {
log_error (_("error in '%s': %s\n"), fname, _("line too long") );
/* ... or last line does not have a LF */
break; /* can't continue */
}
for(p = line; *p && *p != ':' ; p++ )
if( !hexdigitp(p) )
break;
if( *p != ':' ) {
log_error (_("error in '%s': %s\n"), fname, _("colon missing") );
continue;
}
fprlen = p - line;
if( fprlen != 32 && fprlen != 40 && fprlen != 64) {
log_error (_("error in '%s': %s\n"),
fname, _("invalid fingerprint") );
continue;
}
if( sscanf(p, ":%u:", &otrust ) != 1 ) {
log_error (_("error in '%s': %s\n"),
fname, _("ownertrust value missing"));
continue;
}
if( !otrust )
continue; /* no otrust defined - no need to update or insert */
/* Convert the ascii fingerprint to binary */
for(p=line, fprlen=0;
fprlen < MAX_FINGERPRINT_LEN && *p != ':';
p += 2 )
fpr[fprlen++] = HEXTOBIN(p[0]) * 16 + HEXTOBIN(p[1]);
while (fprlen < MAX_FINGERPRINT_LEN)
fpr[fprlen++] = 0;
rc = tdbio_search_trust_byfpr (fpr, &rec);
if( !rc ) { /* found: update */
if (rec.r.trust.ownertrust != otrust)
{
if (!opt.quiet)
{
if( rec.r.trust.ownertrust )
log_info("changing ownertrust from %u to %u\n",
rec.r.trust.ownertrust, otrust );
else
log_info("setting ownertrust to %u\n", otrust );
}
rec.r.trust.ownertrust = otrust;
write_record (ctrl, &rec);
any = 1;
}
}
else if (gpg_err_code (rc) == GPG_ERR_NOT_FOUND) { /* insert */
if (!opt.quiet)
log_info("inserting ownertrust of %u\n", otrust );
memset (&rec, 0, sizeof rec);
rec.recnum = tdbio_new_recnum (ctrl);
rec.rectype = RECTYPE_TRUST;
memcpy (rec.r.trust.fingerprint, fpr, 20);
rec.r.trust.ownertrust = otrust;
write_record (ctrl, &rec);
any = 1;
}
else /* error */
log_error (_("error finding trust record in '%s': %s\n"),
fname, gpg_strerror (rc));
}
if (es_ferror (fp))
log_error ( _("read error in '%s': %s\n"), fname, strerror(errno) );
if (!is_stdin)
es_fclose (fp);
if (any)
{
revalidation_mark (ctrl);
rc = tdbio_sync ();
if (rc)
log_error (_("trustdb: sync failed: %s\n"), gpg_strerror (rc) );
}
}
