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release 0.2.3

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This commit is contained in:
Werner Koch 1998-02-09 17:43:42 +00:00
parent b18d1107ec
commit d6fa02add6
41 changed files with 464 additions and 110 deletions
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76
g10/armor.c
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@ -171,6 +171,52 @@ invalid_armor(void)
}
/****************
* check wether the armor header is valid on a signed message.
* this is for security reasons: the header lines are not included in the
* hash and by using some creative formatting rules, Mallory could fake
* any text at the beginning of a document; assuming it is read with
* a simple viewer. We do only allow the Hash Header.
*/
static int
parse_hash_header( const char *line )
{
const char *s, *s2;
unsigned found = 0;
if( strlen(line) < 6 || strlen(line) > 60 )
return 0; /* too short or too long */
if( memcmp( line, "Hash:", 5 ) )
return 0; /* invalid header */
s = line+5;
for(s=line+5;;s=s2) {
for(; *s && (*s==' ' || *s == '\t'); s++ )
;
if( !*s )
break;
for(s2=s+1; *s2 && *s2!=' ' && *s2 != '\t' && *s2 != ','; s2++ )
;
if( !strncmp( s, "RIPEMD160", s2-s ) )
found |= 1;
else if( !strncmp( s, "SHA1", s2-s ) )
found |= 2;
else if( !strncmp( s, "MD5", s2-s ) )
found |= 4;
else if( !strncmp( s, "MD2", s2-s ) )
found |= 8;
else
return 0;
for(; *s2 && (*s2==' ' || *s2 == '\t'); s2++ )
;
if( *s2 && *s2 != ',' )
return 0;
if( *s2 )
s2++;
}
return found;
}
/****************
* parse an ascii armor.
* Returns: the state,
@ -197,15 +243,17 @@ find_header( fhdr_state_t state, byte *buf, size_t *r_buflen,
do {
switch( state ) {
case fhdrHASArmor:
/* read 28 bytes, which is the bare minimum for a BEGIN...
* and check wether this has a Armor. */
/* read at least the first byte to check wether it is armored
* or not */
c = 0;
for(n=0; n < 28 && (c=iobuf_get2(a)) != -1 && c != '\n'; )
buf[n++] = c;
if( n < 28 || c == -1 )
if( !n || c == -1 )
state = fhdrNOArmor; /* too short */
else if( !is_armored( buf ) )
state = fhdrNOArmor;
else if( c == '\n' )
state = fhdrCHECKBegin;
else
state = fhdrINITCont;
break;
@ -243,7 +291,12 @@ find_header( fhdr_state_t state, byte *buf, size_t *r_buflen,
log_debug("armor header: ");
print_string( stderr, buf, n );
putc('\n', stderr);
state = fhdrWAITHeader;
if( clearsig && !parse_hash_header( buf ) ) {
log_error("invalid clearsig header\n");
state = fhdrERROR;
}
else
state = fhdrWAITHeader;
}
else
state = fhdrCHECKDashEscaped3;
@ -605,7 +658,6 @@ fake_packet( armor_filter_context_t *afx, IOBUF a,
break;
case fhdrENDClearsig:
log_debug("endclearsig: emplines=%u n=%u\n", emplines, n );
assert( emplines );
emplines--; /* don't count the last one */
state = fhdrENDClearsigHelp;
@ -760,12 +812,14 @@ armor_filter( void *opaque, int control,
int idx, idx2;
size_t n=0;
u32 crc;
#if 1
static FILE *fp ;
if( !fp ) {
fp = fopen("armor.out", "w");
assert(fp);
}
#endif
if( DBG_FILTER )
log_debug("armor-filter: control: %d\n", control );
@ -794,8 +848,14 @@ armor_filter( void *opaque, int control,
rc = fake_packet( afx, a, &n, buf, size );
else if( !afx->inp_checked ) {
rc = check_input( afx, a );
if( afx->inp_bypass )
;
if( afx->inp_bypass ) {
for( n=0; n < size && n < afx->helplen; n++ )
buf[n] = afx->helpbuf[n];
if( !n )
rc = -1;
assert( n == afx->helplen );
afx->helplen = 0;
}
else if( afx->faked ) {
/* the buffer is at least 30 bytes long, so it
* is easy to construct the packets */
@ -824,9 +884,11 @@ armor_filter( void *opaque, int control,
}
else
rc = radix64_read( afx, a, &n, buf, size );
#if 1
if( n )
if( fwrite(buf, n, 1, fp ) != 1 )
BUG();
#endif
*ret_len = n;
}
else if( control == IOBUFCTRL_FLUSH ) {