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-rw-r--r--g10/armor.c1474
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diff --git a/g10/armor.c b/g10/armor.c
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--- /dev/null
+++ b/g10/armor.c
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+/* armor.c - Armor flter
+ * Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
+ * 2006 Free Software Foundation, Inc.
+ *
+ * This file is part of GnuPG.
+ *
+ * GnuPG is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * GnuPG is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
+ * USA.
+ */
+
+#include <config.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <assert.h>
+#include <ctype.h>
+
+#include "errors.h"
+#include "iobuf.h"
+#include "memory.h"
+#include "util.h"
+#include "filter.h"
+#include "packet.h"
+#include "options.h"
+#include "main.h"
+#include "status.h"
+#include "i18n.h"
+
+#define MAX_LINELEN 20000
+
+#define CRCINIT 0xB704CE
+#define CRCPOLY 0X864CFB
+#define CRCUPDATE(a,c) do { \
+ a = ((a) << 8) ^ crc_table[((a)&0xff >> 16) ^ (c)]; \
+ a &= 0x00ffffff; \
+ } while(0)
+static u32 crc_table[256];
+static byte bintoasc[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+ "abcdefghijklmnopqrstuvwxyz"
+ "0123456789+/";
+static byte asctobin[256]; /* runtime initialized */
+static int is_initialized;
+
+
+typedef enum {
+ fhdrHASArmor = 0,
+ fhdrNOArmor,
+ fhdrINIT,
+ fhdrINITCont,
+ fhdrINITSkip,
+ fhdrCHECKBegin,
+ fhdrWAITHeader,
+ fhdrWAITClearsig,
+ fhdrSKIPHeader,
+ fhdrCLEARSIG,
+ fhdrREADClearsig,
+ fhdrNullClearsig,
+ fhdrEMPTYClearsig,
+ fhdrCHECKClearsig,
+ fhdrCHECKClearsig2,
+ fhdrCHECKDashEscaped,
+ fhdrCHECKDashEscaped2,
+ fhdrCHECKDashEscaped3,
+ fhdrREADClearsigNext,
+ fhdrENDClearsig,
+ fhdrENDClearsigHelp,
+ fhdrTESTSpaces,
+ fhdrCLEARSIGSimple,
+ fhdrCLEARSIGSimpleNext,
+ fhdrTEXT,
+ fhdrTEXTSimple,
+ fhdrERROR,
+ fhdrERRORShow,
+ fhdrEOF
+} fhdr_state_t;
+
+
+/* if we encounter this armor string with this index, go
+ * into a mode which fakes packets and wait for the next armor */
+#define BEGIN_SIGNATURE 2
+#define BEGIN_SIGNED_MSG_IDX 3
+static char *head_strings[] = {
+ "BEGIN PGP MESSAGE",
+ "BEGIN PGP PUBLIC KEY BLOCK",
+ "BEGIN PGP SIGNATURE",
+ "BEGIN PGP SIGNED MESSAGE",
+ "BEGIN PGP ARMORED FILE", /* gnupg extension */
+ "BEGIN PGP PRIVATE KEY BLOCK",
+ "BEGIN PGP SECRET KEY BLOCK", /* only used by pgp2 */
+ NULL
+};
+static char *tail_strings[] = {
+ "END PGP MESSAGE",
+ "END PGP PUBLIC KEY BLOCK",
+ "END PGP SIGNATURE",
+ "END dummy",
+ "END PGP ARMORED FILE",
+ "END PGP PRIVATE KEY BLOCK",
+ "END PGP SECRET KEY BLOCK",
+ NULL
+};
+
+
+/* Create a new context for armor filters. */
+armor_filter_context_t *
+new_armor_context (void)
+{
+ armor_filter_context_t *afx;
+
+ afx = xcalloc (1, sizeof *afx);
+ afx->refcount = 1;
+
+ return afx;
+}
+
+/* Release an armor filter context. Passing NULL is explicitly
+ allowed and a no-op. */
+void
+release_armor_context (armor_filter_context_t *afx)
+{
+ if (!afx)
+ return;
+
+ /* In contrast to 2.0, we use in 1.4 heap based contexts only in a
+ very few places and in general keep the stack based contexts. A
+ REFCOUNT of 0 indicates a stack based context and thus we don't
+ do anything in this case. */
+ if (!afx->refcount)
+ return;
+
+ if ( --afx->refcount )
+ return;
+ xfree (afx);
+}
+
+/* Push the armor filter onto the iobuf stream IOBUF. */
+int
+push_armor_filter (armor_filter_context_t *afx, iobuf_t iobuf)
+{
+ int rc;
+
+ if (!afx->refcount)
+ return iobuf_push_filter (iobuf, armor_filter, afx);
+
+ afx->refcount++;
+ rc = iobuf_push_filter (iobuf, armor_filter, afx);
+ if (rc)
+ afx->refcount--;
+ return rc;
+}
+
+
+
+
+
+static void
+initialize(void)
+{
+ int i, j;
+ u32 t;
+ byte *s;
+
+ /* init the crc lookup table */
+ crc_table[0] = 0;
+ for(i=j=0; j < 128; j++ ) {
+ t = crc_table[j];
+ if( t & 0x00800000 ) {
+ t <<= 1;
+ crc_table[i++] = t ^ CRCPOLY;
+ crc_table[i++] = t;
+ }
+ else {
+ t <<= 1;
+ crc_table[i++] = t;
+ crc_table[i++] = t ^ CRCPOLY;
+ }
+ }
+ /* build the helptable for radix64 to bin conversion */
+ for(i=0; i < 256; i++ )
+ asctobin[i] = 255; /* used to detect invalid characters */
+ for(s=bintoasc,i=0; *s; s++,i++ )
+ asctobin[*s] = i;
+
+ is_initialized=1;
+}
+
+/****************
+ * Check whether this is an armored file or not See also
+ * parse-packet.c for details on this code For unknown historic
+ * reasons we use a string here but only the first byte will be used.
+ * Returns: True if it seems to be armored
+ */
+static int
+is_armored( const byte *buf )
+{
+ int ctb, pkttype;
+
+ ctb = *buf;
+ if( !(ctb & 0x80) )
+ return 1; /* invalid packet: assume it is armored */
+ pkttype = ctb & 0x40 ? (ctb & 0x3f) : ((ctb>>2)&0xf);
+ switch( pkttype ) {
+ case PKT_MARKER:
+ case PKT_SYMKEY_ENC:
+ case PKT_ONEPASS_SIG:
+ case PKT_PUBLIC_KEY:
+ case PKT_SECRET_KEY:
+ case PKT_PUBKEY_ENC:
+ case PKT_SIGNATURE:
+ case PKT_COMMENT:
+ case PKT_OLD_COMMENT:
+ case PKT_PLAINTEXT:
+ case PKT_COMPRESSED:
+ case PKT_ENCRYPTED:
+ return 0; /* seems to be a regular packet: not armored */
+ }
+
+ return 1;
+}
+
+
+/****************
+ * Try to check whether the iobuf is armored
+ * Returns true if this may be the case; the caller should use the
+ * filter to do further processing.
+ */
+int
+use_armor_filter( IOBUF a )
+{
+ byte buf[1];
+ int n;
+
+ /* fixme: there might be a problem with iobuf_peek */
+ n = iobuf_peek(a, buf, 1 );
+ if( n == -1 )
+ return 0; /* EOF, doesn't matter whether armored or not */
+ if( !n )
+ return 1; /* can't check it: try armored */
+ return is_armored(buf);
+}
+
+
+
+
+static void
+invalid_armor(void)
+{
+ write_status(STATUS_BADARMOR);
+ g10_exit(1); /* stop here */
+}
+
+
+/****************
+ * check whether 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 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, "SHA224", s2-s ) )
+ found |= 8;
+ else if( !strncmp( s, "SHA256", s2-s ) )
+ found |= 16;
+ else if( !strncmp( s, "SHA384", s2-s ) )
+ found |= 32;
+ else if( !strncmp( s, "SHA512", s2-s ) )
+ found |= 64;
+ else
+ return 0;
+ for(; *s2 && (*s2==' ' || *s2 == '\t'); s2++ )
+ ;
+ if( *s2 && *s2 != ',' )
+ return 0;
+ if( *s2 )
+ s2++;
+ }
+ return found;
+}
+
+
+
+/****************
+ * Check whether this is a armor line.
+ * returns: -1 if it is not a armor header or the index number of the
+ * armor header.
+ */
+static int
+is_armor_header( byte *line, unsigned len )
+{
+ const char *s;
+ byte *save_p, *p;
+ int save_c;
+ int i;
+
+ if( len < 15 )
+ return -1; /* too short */
+ if( memcmp( line, "-----", 5 ) )
+ return -1; /* no */
+ p = strstr( line+5, "-----");
+ if( !p )
+ return -1;
+ save_p = p;
+ p += 5;
+
+ /* Some Windows environments seem to add whitespace to the end of
+ the line, so we strip it here. This becomes strict if
+ --rfc2440 is set since 2440 reads "The header lines, therefore,
+ MUST start at the beginning of a line, and MUST NOT have text
+ following them on the same line." It is unclear whether "text"
+ refers to all text or just non-whitespace text. */
+
+ if(RFC2440)
+ {
+ if( *p == '\r' )
+ p++;
+ if( *p == '\n' )
+ p++;
+ }
+ else
+ while(*p==' ' || *p=='\r' || *p=='\n' || *p=='\t')
+ p++;
+
+ if( *p )
+ return -1; /* garbage after dashes */
+ save_c = *save_p; *save_p = 0;
+ p = line+5;
+ for(i=0; (s=head_strings[i]); i++ )
+ if( !strcmp(s, p) )
+ break;
+ *save_p = save_c;
+ if( !s )
+ return -1; /* unknown armor line */
+
+ if( opt.verbose > 1 )
+ log_info(_("armor: %s\n"), head_strings[i]);
+ return i;
+}
+
+
+
+/****************
+ * Parse a header lines
+ * Return 0: Empty line (end of header lines)
+ * -1: invalid header line
+ * >0: Good header line
+ */
+static int
+parse_header_line( armor_filter_context_t *afx, byte *line, unsigned int len )
+{
+ byte *p;
+ int hashes=0;
+ unsigned int len2;
+
+ len2 = check_trailing_ws( line, len );
+ if( !len2 ) {
+ afx->buffer_pos = len2; /* (it is not the fine way to do it here) */
+ return 0; /* WS only: same as empty line */
+ }
+
+ /*
+ This is fussy. The spec says that a header line is delimited
+ with a colon-space pair. This means that a line such as
+ "Comment: " (with nothing else) is actually legal as an empty
+ string comment. However, email and cut-and-paste being what it
+ is, that trailing space may go away. Therefore, we accept empty
+ headers delimited with only a colon. --rfc2440, as always,
+ makes this strict and enforces the colon-space pair. -dms
+ */
+
+ p = strchr( line, ':');
+ if( !p || (RFC2440 && p[1]!=' ')
+ || (!RFC2440 && p[1]!=' ' && p[1]!='\n' && p[1]!='\r'))
+ {
+ log_error(_("invalid armor header: "));
+ print_string( stderr, line, len, 0 );
+ putc('\n', stderr);
+ return -1;
+ }
+
+ /* Chop off the whitespace we detected before */
+ len=len2;
+ line[len2]='\0';
+
+ if( opt.verbose ) {
+ log_info(_("armor header: "));
+ print_string( stderr, line, len, 0 );
+ putc('\n', stderr);
+ }
+
+ if( afx->in_cleartext ) {
+ if( (hashes=parse_hash_header( line )) )
+ afx->hashes |= hashes;
+ else if( strlen(line) > 15 && !memcmp( line, "NotDashEscaped:", 15 ) )
+ afx->not_dash_escaped = 1;
+ else {
+ log_error(_("invalid clearsig header\n"));
+ return -1;
+ }
+ }
+ return 1;
+}
+
+
+
+/* figure out whether the data is armored or not */
+static int
+check_input( armor_filter_context_t *afx, IOBUF a )
+{
+ int rc = 0;
+ int i;
+ byte *line;
+ unsigned len;
+ unsigned maxlen;
+ int hdr_line = -1;
+
+ /* read the first line to see whether this is armored data */
+ maxlen = MAX_LINELEN;
+ len = afx->buffer_len = iobuf_read_line( a, &afx->buffer,
+ &afx->buffer_size, &maxlen );
+ line = afx->buffer;
+ if( !maxlen ) {
+ /* line has been truncated: assume not armored */
+ afx->inp_checked = 1;
+ afx->inp_bypass = 1;
+ return 0;
+ }
+
+ if( !len ) {
+ return -1; /* eof */
+ }
+
+ /* (the line is always a C string but maybe longer) */
+ if( *line == '\n' || ( len && (*line == '\r' && line[1]=='\n') ) )
+ ;
+ else if( !is_armored( line ) ) {
+ afx->inp_checked = 1;
+ afx->inp_bypass = 1;
+ return 0;
+ }
+
+ /* find the armor header */
+ while(len) {
+ i = is_armor_header( line, len );
+ if( i >= 0 && !(afx->only_keyblocks && i != 1 && i != 5 && i != 6 )) {
+ hdr_line = i;
+ if( hdr_line == BEGIN_SIGNED_MSG_IDX ) {
+ if( afx->in_cleartext ) {
+ log_error(_("nested clear text signatures\n"));
+ rc = G10ERR_INVALID_ARMOR;
+ }
+ afx->in_cleartext = 1;
+ }
+ break;
+ }
+ /* read the next line (skip all truncated lines) */
+ do {
+ maxlen = MAX_LINELEN;
+ afx->buffer_len = iobuf_read_line( a, &afx->buffer,
+ &afx->buffer_size, &maxlen );
+ line = afx->buffer;
+ len = afx->buffer_len;
+ } while( !maxlen );
+ }
+
+ /* Parse the header lines. */
+ while(len) {
+ /* Read the next line (skip all truncated lines). */
+ do {
+ maxlen = MAX_LINELEN;
+ afx->buffer_len = iobuf_read_line( a, &afx->buffer,
+ &afx->buffer_size, &maxlen );
+ line = afx->buffer;
+ len = afx->buffer_len;
+ } while( !maxlen );
+
+ i = parse_header_line( afx, line, len );
+ if( i <= 0 ) {
+ if (i && RFC2440)
+ rc = G10ERR_INVALID_ARMOR;
+ break;
+ }
+ }
+
+
+ if( rc )
+ invalid_armor();
+ else if( afx->in_cleartext )
+ afx->faked = 1;
+ else {
+ afx->inp_checked = 1;
+ afx->crc = CRCINIT;
+ afx->idx = 0;
+ afx->radbuf[0] = 0;
+ }
+
+ return rc;
+}
+
+#define PARTIAL_CHUNK 512
+#define PARTIAL_POW 9
+
+/****************
+ * Fake a literal data packet and wait for the next armor line
+ * fixme: empty line handling and null length clear text signature are
+ * not implemented/checked.
+ */
+static int
+fake_packet( armor_filter_context_t *afx, IOBUF a,
+ size_t *retn, byte *buf, size_t size )
+{
+ int rc = 0;
+ size_t len = 0;
+ int lastline = 0;
+ unsigned maxlen, n;
+ byte *p;
+ byte tempbuf[PARTIAL_CHUNK];
+ size_t tempbuf_len=0;
+
+ while( !rc && size-len>=(PARTIAL_CHUNK+1)) {
+ /* copy what we have in the line buffer */
+ if( afx->faked == 1 )
+ afx->faked++; /* skip the first (empty) line */
+ else
+ {
+ /* It's full, so write this partial chunk */
+ if(tempbuf_len==PARTIAL_CHUNK)
+ {
+ buf[len++]=0xE0+PARTIAL_POW;
+ memcpy(&buf[len],tempbuf,PARTIAL_CHUNK);
+ len+=PARTIAL_CHUNK;
+ tempbuf_len=0;
+ continue;
+ }
+
+ while( tempbuf_len < PARTIAL_CHUNK
+ && afx->buffer_pos < afx->buffer_len )
+ tempbuf[tempbuf_len++] = afx->buffer[afx->buffer_pos++];
+ if( tempbuf_len==PARTIAL_CHUNK )
+ continue;
+ }
+
+ /* read the next line */
+ maxlen = MAX_LINELEN;
+ afx->buffer_pos = 0;
+ afx->buffer_len = iobuf_read_line( a, &afx->buffer,
+ &afx->buffer_size, &maxlen );
+ if( !afx->buffer_len ) {
+ rc = -1; /* eof (should not happen) */
+ continue;
+ }
+ if( !maxlen )
+ afx->truncated++;
+
+ p = afx->buffer;
+ n = afx->buffer_len;
+
+ /* Armor header or dash-escaped line? */
+ if(p[0]=='-')
+ {
+ /* 2440bis-10: When reversing dash-escaping, an
+ implementation MUST strip the string "- " if it occurs
+ at the beginning of a line, and SHOULD warn on "-" and
+ any character other than a space at the beginning of a
+ line. */
+
+ if(p[1]==' ' && !afx->not_dash_escaped)
+ {
+ /* It's a dash-escaped line, so skip over the
+ escape. */
+ afx->buffer_pos = 2;
+ }
+ else if(p[1]=='-' && p[2]=='-' && p[3]=='-' && p[4]=='-')
+ {
+ /* Five dashes in a row mean it's probably armor
+ header. */
+ int type = is_armor_header( p, n );
+ if( afx->not_dash_escaped && type != BEGIN_SIGNATURE )
+ ; /* this is okay */
+ else
+ {
+ if( type != BEGIN_SIGNATURE )
+ {
+ log_info(_("unexpected armor: "));
+ print_string( stderr, p, n, 0 );
+ putc('\n', stderr);
+ }
+
+ lastline = 1;
+ rc = -1;
+ }
+ }
+ else if(!afx->not_dash_escaped)
+ {
+ /* Bad dash-escaping. */
+ log_info(_("invalid dash escaped line: "));
+ print_string( stderr, p, n, 0 );
+ putc('\n', stderr);
+ }
+ }
+
+ /* Now handle the end-of-line canonicalization */
+ if( !afx->not_dash_escaped )
+ {
+ int crlf = n > 1 && p[n-2] == '\r' && p[n-1]=='\n';
+
+ /* PGP2 does not treat a tab as white space character */
+ afx->buffer_len=
+ trim_trailing_chars( &p[afx->buffer_pos], n-afx->buffer_pos,
+ afx->pgp2mode ? " \r\n" : " \t\r\n");
+ afx->buffer_len+=afx->buffer_pos;
+ /* the buffer is always allocated with enough space to append
+ * the removed [CR], LF and a Nul
+ * The reason for this complicated procedure is to keep at least
+ * the original type of lineending - handling of the removed
+ * trailing spaces seems to be impossible in our method
+ * of faking a packet; either we have to use a temporary file
+ * or calculate the hash here in this module and somehow find
+ * a way to send the hash down the processing line (well, a special
+ * faked packet could do the job).
+ */
+ if( crlf )
+ afx->buffer[afx->buffer_len++] = '\r';
+ afx->buffer[afx->buffer_len++] = '\n';
+ afx->buffer[afx->buffer_len] = '\0';
+ }
+ }
+
+ if( lastline ) { /* write last (ending) length header */
+ if(tempbuf_len<192)
+ buf[len++]=tempbuf_len;
+ else
+ {
+ buf[len++]=((tempbuf_len-192)/256) + 192;
+ buf[len++]=(tempbuf_len-192) % 256;
+ }
+ memcpy(&buf[len],tempbuf,tempbuf_len);
+ len+=tempbuf_len;
+
+ rc = 0;
+ afx->faked = 0;
+ afx->in_cleartext = 0;
+ /* and now read the header lines */
+ afx->buffer_pos = 0;
+ for(;;) {
+ int i;
+
+ /* read the next line (skip all truncated lines) */
+ do {
+ maxlen = MAX_LINELEN;
+ afx->buffer_len = iobuf_read_line( a, &afx->buffer,
+ &afx->buffer_size, &maxlen );
+ } while( !maxlen );
+ p = afx->buffer;
+ n = afx->buffer_len;
+ if( !n ) {
+ rc = -1;
+ break; /* eof */
+ }
+ i = parse_header_line( afx, p , n );
+ if( i <= 0 ) {
+ if( i )
+ invalid_armor();
+ break;
+ }
+ }
+ afx->inp_checked = 1;
+ afx->crc = CRCINIT;
+ afx->idx = 0;
+ afx->radbuf[0] = 0;
+ }
+
+ *retn = len;
+ return rc;
+}
+
+
+static int
+invalid_crc(void)
+{
+ if ( opt.ignore_crc_error )
+ return 0;
+ log_inc_errorcount();
+ return G10ERR_INVALID_ARMOR;
+}
+
+
+static int
+radix64_read( armor_filter_context_t *afx, IOBUF a, size_t *retn,
+ byte *buf, size_t size )
+{
+ byte val;
+ int c=0, c2; /*init c because gcc is not clever enough for the continue*/
+ int checkcrc=0;
+ int rc = 0;
+ size_t n = 0;
+ int idx, i, onlypad=0;
+ u32 crc;
+
+ crc = afx->crc;
+ idx = afx->idx;
+ val = afx->radbuf[0];
+ for( n=0; n < size; ) {
+
+ if( afx->buffer_pos < afx->buffer_len )
+ c = afx->buffer[afx->buffer_pos++];
+ else { /* read the next line */
+ unsigned maxlen = MAX_LINELEN;
+ afx->buffer_pos = 0;
+ afx->buffer_len = iobuf_read_line( a, &afx->buffer,
+ &afx->buffer_size, &maxlen );
+ if( !maxlen )
+ afx->truncated++;
+ if( !afx->buffer_len )
+ break; /* eof */
+ continue;
+ }
+
+ again:
+ if( c == '\n' || c == ' ' || c == '\r' || c == '\t' )
+ continue;
+ else if( c == '=' ) { /* pad character: stop */
+ /* some mailers leave quoted-printable encoded characters
+ * so we try to workaround this */
+ if( afx->buffer_pos+2 < afx->buffer_len ) {
+ int cc1, cc2, cc3;
+ cc1 = afx->buffer[afx->buffer_pos];
+ cc2 = afx->buffer[afx->buffer_pos+1];
+ cc3 = afx->buffer[afx->buffer_pos+2];
+ if( isxdigit(cc1) && isxdigit(cc2)
+ && strchr( "=\n\r\t ", cc3 )) {
+ /* well it seems to be the case - adjust */
+ c = isdigit(cc1)? (cc1 - '0'): (ascii_toupper(cc1)-'A'+10);
+ c <<= 4;
+ c |= isdigit(cc2)? (cc2 - '0'): (ascii_toupper(cc2)-'A'+10);
+ afx->buffer_pos += 2;
+ afx->qp_detected = 1;
+ goto again;
+ }
+ }
+ else if(n==0)
+ onlypad=1;
+
+ if( idx == 1 )
+ buf[n++] = val;
+ checkcrc++;
+ break;
+ }
+ else if( (c = asctobin[(c2=c)]) == 255 ) {
+ log_error(_("invalid radix64 character %02X skipped\n"), c2);
+ continue;
+ }
+ switch(idx) {
+ case 0: val = c << 2; break;
+ case 1: val |= (c>>4)&3; buf[n++]=val;val=(c<<4)&0xf0;break;
+ case 2: val |= (c>>2)&15; buf[n++]=val;val=(c<<6)&0xc0;break;
+ case 3: val |= c&0x3f; buf[n++] = val; break;
+ }
+ idx = (idx+1) % 4;
+ }
+
+ for(i=0; i < n; i++ )
+ crc = (crc << 8) ^ crc_table[((crc >> 16)&0xff) ^ buf[i]];
+ crc &= 0x00ffffff;
+ afx->crc = crc;
+ afx->idx = idx;
+ afx->radbuf[0] = val;
+
+ if( checkcrc ) {
+ afx->any_data = 1;
+ afx->inp_checked=0;
+ afx->faked = 0;
+ for(;;) { /* skip lf and pad characters */
+ if( afx->buffer_pos < afx->buffer_len )
+ c = afx->buffer[afx->buffer_pos++];
+ else { /* read the next line */
+ unsigned maxlen = MAX_LINELEN;
+ afx->buffer_pos = 0;
+ afx->buffer_len = iobuf_read_line( a, &afx->buffer,
+ &afx->buffer_size, &maxlen );
+ if( !maxlen )
+ afx->truncated++;
+ if( !afx->buffer_len )
+ break; /* eof */
+ continue;
+ }
+ if( c == '\n' || c == ' ' || c == '\r'
+ || c == '\t' || c == '=' )
+ continue;
+ break;
+ }
+ if( c == -1 )
+ log_error(_("premature eof (no CRC)\n"));
+ else {
+ u32 mycrc = 0;
+ idx = 0;
+ do {
+ if( (c = asctobin[c]) == 255 )
+ break;
+ switch(idx) {
+ case 0: val = c << 2; break;
+ case 1: val |= (c>>4)&3; mycrc |= val << 16;val=(c<<4)&0xf0;break;
+ case 2: val |= (c>>2)&15; mycrc |= val << 8;val=(c<<6)&0xc0;break;
+ case 3: val |= c&0x3f; mycrc |= val; break;
+ }
+ for(;;) {
+ if( afx->buffer_pos < afx->buffer_len )
+ c = afx->buffer[afx->buffer_pos++];
+ else { /* read the next line */
+ unsigned maxlen = MAX_LINELEN;
+ afx->buffer_pos = 0;
+ afx->buffer_len = iobuf_read_line( a, &afx->buffer,
+ &afx->buffer_size,
+ &maxlen );
+ if( !maxlen )
+ afx->truncated++;
+ if( !afx->buffer_len )
+ break; /* eof */
+ continue;
+ }
+ break;
+ }
+ if( !afx->buffer_len )
+ break; /* eof */
+ } while( ++idx < 4 );
+ if( c == -1 ) {
+ log_info(_("premature eof (in CRC)\n"));
+ rc = invalid_crc();
+ }
+ else if( idx == 0 ) {
+ /* No CRC at all is legal ("MAY") */
+ rc=0;
+ }
+ else if( idx != 4 ) {
+ log_info(_("malformed CRC\n"));
+ rc = invalid_crc();
+ }
+ else if( mycrc != afx->crc ) {
+ log_info (_("CRC error; %06lX - %06lX\n"),
+ (ulong)afx->crc, (ulong)mycrc);
+ rc = invalid_crc();
+ }
+ else {
+ rc = 0;
+ /* FIXME: Here we should emit another control packet,
+ * so that we know in mainproc that we are processing
+ * a clearsign message */
+#if 0
+ for(rc=0;!rc;) {
+ rc = 0 /*check_trailer( &fhdr, c )*/;
+ if( !rc ) {
+ if( (c=iobuf_get(a)) == -1 )
+ rc = 2;
+ }
+ }
+ if( rc == -1 )
+ rc = 0;
+ else if( rc == 2 ) {
+ log_error(_("premature eof (in trailer)\n"));
+ rc = G10ERR_INVALID_ARMOR;
+ }
+ else {
+ log_error(_("error in trailer line\n"));
+ rc = G10ERR_INVALID_ARMOR;
+ }
+#endif
+ }
+ }
+ }
+
+ if( !n && !onlypad )
+ rc = -1;
+
+ *retn = n;
+ return rc;
+}
+
+/****************
+ * This filter is used to handle the armor stuff
+ */
+int
+armor_filter( void *opaque, int control,
+ IOBUF a, byte *buf, size_t *ret_len)
+{
+ size_t size = *ret_len;
+ armor_filter_context_t *afx = opaque;
+ int rc=0, i, c;
+ byte radbuf[3];
+ int idx, idx2;
+ size_t n=0;
+ u32 crc;
+#if 0
+ static FILE *fp ;
+
+ if( !fp ) {
+ fp = fopen("armor.out", "w");
+ assert(fp);
+ }
+#endif
+
+ if( DBG_FILTER )
+ log_debug("armor-filter: control: %d\n", control );
+ if( control == IOBUFCTRL_UNDERFLOW && afx->inp_bypass ) {
+ n = 0;
+ if( afx->buffer_len ) {
+ for(; n < size && afx->buffer_pos < afx->buffer_len; n++ )
+ buf[n++] = afx->buffer[afx->buffer_pos++];
+ if( afx->buffer_pos >= afx->buffer_len )
+ afx->buffer_len = 0;
+ }
+ for(; n < size; n++ ) {
+ if( (c=iobuf_get(a)) == -1 )
+ break;
+ buf[n] = c & 0xff;
+ }
+ if( !n )
+ rc = -1;
+ *ret_len = n;
+ }
+ else if( control == IOBUFCTRL_UNDERFLOW ) {
+ /* We need some space for the faked packet. The minmum
+ * required size is the PARTIAL_CHUNK size plus a byte for the
+ * length itself */
+ if( size < PARTIAL_CHUNK+1 )
+ BUG(); /* supplied buffer too short */
+
+ if( afx->faked )
+ rc = fake_packet( afx, a, &n, buf, size );
+ else if( !afx->inp_checked ) {
+ rc = check_input( afx, a );
+ if( afx->inp_bypass ) {
+ for(n=0; n < size && afx->buffer_pos < afx->buffer_len; )
+ buf[n++] = afx->buffer[afx->buffer_pos++];
+ if( afx->buffer_pos >= afx->buffer_len )
+ afx->buffer_len = 0;
+ if( !n )
+ rc = -1;
+ }
+ else if( afx->faked ) {
+ unsigned int hashes = afx->hashes;
+ const byte *sesmark;
+ size_t sesmarklen;
+
+ sesmark = get_session_marker( &sesmarklen );
+ if ( sesmarklen > 20 )
+ BUG();
+
+ /* the buffer is at least 15+n*15 bytes long, so it
+ * is easy to construct the packets */
+
+ hashes &= 1|2|4|8|16|32|64;
+ if( !hashes ) {
+ hashes |= 4; /* default to MD 5 */
+ /* This is non-ideal since PGP 5-8 have the same
+ end-of-line bugs as PGP 2. However, we only
+ enable pgp2mode if there is no Hash: header. */
+ if( opt.pgp2_workarounds )
+ afx->pgp2mode = 1;
+ }
+ n=0;
+ /* First a gpg control packet... */
+ buf[n++] = 0xff; /* new format, type 63, 1 length byte */
+ n++; /* see below */
+ memcpy(buf+n, sesmark, sesmarklen ); n+= sesmarklen;
+ buf[n++] = CTRLPKT_CLEARSIGN_START;
+ buf[n++] = afx->not_dash_escaped? 0:1; /* sigclass */
+ if( hashes & 1 )
+ buf[n++] = DIGEST_ALGO_RMD160;
+ if( hashes & 2 )
+ buf[n++] = DIGEST_ALGO_SHA1;
+ if( hashes & 4 )
+ buf[n++] = DIGEST_ALGO_MD5;
+ if( hashes & 8 )
+ buf[n++] = DIGEST_ALGO_SHA224;
+ if( hashes & 16 )
+ buf[n++] = DIGEST_ALGO_SHA256;
+ if( hashes & 32 )
+ buf[n++] = DIGEST_ALGO_SHA384;
+ if( hashes & 64 )
+ buf[n++] = DIGEST_ALGO_SHA512;
+ buf[1] = n - 2;
+
+ /* ...followed by an invented plaintext packet.
+ Amusingly enough, this packet is not compliant with
+ 2440 as the initial partial length is less than 512
+ bytes. Of course, we'll accept it anyway ;) */
+
+ buf[n++] = 0xCB; /* new packet format, type 11 */
+ buf[n++] = 0xE1; /* 2^1 == 2 bytes */
+ buf[n++] = 't'; /* canonical text mode */
+ buf[n++] = 0; /* namelength */
+ buf[n++] = 0xE2; /* 2^2 == 4 more bytes */
+ memset(buf+n, 0, 4); /* timestamp */
+ n += 4;
+ }
+ else if( !rc )
+ rc = radix64_read( afx, a, &n, buf, size );
+ }
+ else
+ rc = radix64_read( afx, a, &n, buf, size );
+#if 0
+ if( n )
+ if( fwrite(buf, n, 1, fp ) != 1 )
+ BUG();
+#endif
+ *ret_len = n;
+ }
+ else if( control == IOBUFCTRL_FLUSH && !afx->cancel ) {
+ if( !afx->status ) { /* write the header line */
+ const char *s;
+ STRLIST comment=opt.comments;
+
+ if( afx->what >= DIM(head_strings) )
+ log_bug("afx->what=%d", afx->what);
+ iobuf_writestr(a, "-----");
+ iobuf_writestr(a, head_strings[afx->what] );
+ iobuf_writestr(a, "-----" );
+ iobuf_writestr(a,afx->eol);
+ if( !opt.no_version )
+ {
+ iobuf_writestr(a, "Version: GnuPG v" VERSION " ("
+ PRINTABLE_OS_NAME ")" );
+ iobuf_writestr(a,afx->eol);
+ }
+
+ /* write the comment strings */
+ for(s=comment->d;comment;comment=comment->next,s=comment->d)
+ {
+ iobuf_writestr(a, "Comment: " );
+ for( ; *s; s++ )
+ {
+ if( *s == '\n' )
+ iobuf_writestr(a, "\\n" );
+ else if( *s == '\r' )
+ iobuf_writestr(a, "\\r" );
+ else if( *s == '\v' )
+ iobuf_writestr(a, "\\v" );
+ else
+ iobuf_put(a, *s );
+ }
+
+ iobuf_writestr(a,afx->eol);
+ }
+
+ if ( afx->hdrlines ) {
+ for ( s = afx->hdrlines; *s; s++ ) {
+#ifdef HAVE_DOSISH_SYSTEM
+ if ( *s == '\n' )
+ iobuf_put( a, '\r');
+#endif
+ iobuf_put(a, *s );
+ }
+ }
+
+ iobuf_writestr(a,afx->eol);
+ afx->status++;
+ afx->idx = 0;
+ afx->idx2 = 0;
+ afx->crc = CRCINIT;
+
+ }
+ crc = afx->crc;
+ idx = afx->idx;
+ idx2 = afx->idx2;
+ for(i=0; i < idx; i++ )
+ radbuf[i] = afx->radbuf[i];
+
+ for(i=0; i < size; i++ )
+ crc = (crc << 8) ^ crc_table[((crc >> 16)&0xff) ^ buf[i]];
+ crc &= 0x00ffffff;
+
+ for( ; size; buf++, size-- ) {
+ radbuf[idx++] = *buf;
+ if( idx > 2 ) {
+ idx = 0;
+ c = bintoasc[(*radbuf >> 2) & 077];
+ iobuf_put(a, c);
+ c = bintoasc[(((*radbuf<<4)&060)|((radbuf[1] >> 4)&017))&077];
+ iobuf_put(a, c);
+ c = bintoasc[(((radbuf[1]<<2)&074)|((radbuf[2]>>6)&03))&077];
+ iobuf_put(a, c);
+ c = bintoasc[radbuf[2]&077];
+ iobuf_put(a, c);
+ if( ++idx2 >= (64/4) )
+ { /* pgp doesn't like 72 here */
+ iobuf_writestr(a,afx->eol);
+ idx2=0;
+ }
+ }
+ }
+ for(i=0; i < idx; i++ )
+ afx->radbuf[i] = radbuf[i];
+ afx->idx = idx;
+ afx->idx2 = idx2;
+ afx->crc = crc;
+ }
+ else if( control == IOBUFCTRL_INIT )
+ {
+ if( !is_initialized )
+ initialize();
+
+ /* Figure out what we're using for line endings if the caller
+ didn't specify. */
+ if(afx->eol[0]==0)
+ {
+#ifdef HAVE_DOSISH_SYSTEM
+ afx->eol[0]='\r';
+ afx->eol[1]='\n';
+#else
+ afx->eol[0]='\n';
+#endif
+ }
+ }
+ else if( control == IOBUFCTRL_CANCEL ) {
+ afx->cancel = 1;
+ }
+ else if( control == IOBUFCTRL_FREE ) {
+ if( afx->cancel )
+ ;
+ else if( afx->status ) { /* pad, write cecksum, and bottom line */
+ crc = afx->crc;
+ idx = afx->idx;
+ idx2 = afx->idx2;
+ for(i=0; i < idx; i++ )
+ radbuf[i] = afx->radbuf[i];
+ if( idx ) {
+ c = bintoasc[(*radbuf>>2)&077];
+ iobuf_put(a, c);
+ if( idx == 1 ) {
+ c = bintoasc[((*radbuf << 4) & 060) & 077];
+ iobuf_put(a, c);
+ iobuf_put(a, '=');
+ iobuf_put(a, '=');
+ }
+ else { /* 2 */
+ c = bintoasc[(((*radbuf<<4)&060)|((radbuf[1]>>4)&017))&077];
+ iobuf_put(a, c);
+ c = bintoasc[((radbuf[1] << 2) & 074) & 077];
+ iobuf_put(a, c);
+ iobuf_put(a, '=');
+ }
+ if( ++idx2 >= (64/4) )
+ { /* pgp doesn't like 72 here */
+ iobuf_writestr(a,afx->eol);
+ idx2=0;
+ }
+ }
+ /* may need a linefeed */
+ if( idx2 )
+ iobuf_writestr(a,afx->eol);
+ /* write the CRC */
+ iobuf_put(a, '=');
+ radbuf[0] = crc >>16;
+ radbuf[1] = crc >> 8;
+ radbuf[2] = crc;
+ c = bintoasc[(*radbuf >> 2) & 077];
+ iobuf_put(a, c);
+ c = bintoasc[(((*radbuf<<4)&060)|((radbuf[1] >> 4)&017))&077];
+ iobuf_put(a, c);
+ c = bintoasc[(((radbuf[1]<<2)&074)|((radbuf[2]>>6)&03))&077];
+ iobuf_put(a, c);
+ c = bintoasc[radbuf[2]&077];
+ iobuf_put(a, c);
+ iobuf_writestr(a,afx->eol);
+ /* and the the trailer */
+ if( afx->what >= DIM(tail_strings) )
+ log_bug("afx->what=%d", afx->what);
+ iobuf_writestr(a, "-----");
+ iobuf_writestr(a, tail_strings[afx->what] );
+ iobuf_writestr(a, "-----" );
+ iobuf_writestr(a,afx->eol);
+ }
+ else if( !afx->any_data && !afx->inp_bypass ) {
+ log_error(_("no valid OpenPGP data found.\n"));
+ afx->no_openpgp_data = 1;
+ write_status_text( STATUS_NODATA, "1" );
+ }
+ if( afx->truncated )
+ log_info(_("invalid armor: line longer than %d characters\n"),
+ MAX_LINELEN );
+ /* issue an error to enforce dissemination of correct software */
+ if( afx->qp_detected )
+ log_error(_("quoted printable character in armor - "
+ "probably a buggy MTA has been used\n") );
+ xfree( afx->buffer );
+ afx->buffer = NULL;
+ release_armor_context (afx);
+ }
+ else if( control == IOBUFCTRL_DESC )
+ *(char**)buf = "armor_filter";
+ return rc;
+}
+
+
+/****************
+ * create a radix64 encoded string.
+ */
+char *
+make_radix64_string( const byte *data, size_t len )
+{
+ char *buffer, *p;
+
+ buffer = p = xmalloc( (len+2)/3*4 + 1 );
+ for( ; len >= 3 ; len -= 3, data += 3 ) {
+ *p++ = bintoasc[(data[0] >> 2) & 077];
+ *p++ = bintoasc[(((data[0] <<4)&060)|((data[1] >> 4)&017))&077];
+ *p++ = bintoasc[(((data[1]<<2)&074)|((data[2]>>6)&03))&077];
+ *p++ = bintoasc[data[2]&077];
+ }
+ if( len == 2 ) {
+ *p++ = bintoasc[(data[0] >> 2) & 077];
+ *p++ = bintoasc[(((data[0] <<4)&060)|((data[1] >> 4)&017))&077];
+ *p++ = bintoasc[((data[1]<<2)&074)];
+ }
+ else if( len == 1 ) {
+ *p++ = bintoasc[(data[0] >> 2) & 077];
+ *p++ = bintoasc[(data[0] <<4)&060];
+ }
+ *p = 0;
+ return buffer;
+}
+
+
+/***********************************************
+ * For the pipemode command we can't use the armor filter for various
+ * reasons, so we use this new unarmor_pump stuff to remove the armor
+ */
+
+enum unarmor_state_e {
+ STA_init = 0,
+ STA_bypass,
+ STA_wait_newline,
+ STA_wait_dash,
+ STA_first_dash,
+ STA_compare_header,
+ STA_found_header_wait_newline,
+ STA_skip_header_lines,
+ STA_skip_header_lines_non_ws,
+ STA_read_data,
+ STA_wait_crc,
+ STA_read_crc,
+ STA_ready
+};
+
+struct unarmor_pump_s {
+ enum unarmor_state_e state;
+ byte val;
+ int checkcrc;
+ int pos; /* counts from 0..3 */
+ u32 crc;
+ u32 mycrc; /* the one store in the data */
+};
+
+
+
+UnarmorPump
+unarmor_pump_new (void)
+{
+ UnarmorPump x;
+
+ if( !is_initialized )
+ initialize();
+ x = xmalloc_clear (sizeof *x);
+ return x;
+}
+
+void
+unarmor_pump_release (UnarmorPump x)
+{
+ xfree (x);
+}
+
+/*
+ * Get the next character from the ascii armor taken from the IOBUF
+ * created earlier by unarmor_pump_new().
+ * Return: c = Character
+ * 256 = ignore this value
+ * -1 = End of current armor
+ * -2 = Premature EOF (not used)
+ * -3 = Invalid armor
+ */
+int
+unarmor_pump (UnarmorPump x, int c)
+{
+ int rval = 256; /* default is to ignore the return value */
+
+ switch (x->state) {
+ case STA_init:
+ {
+ byte tmp[1];
+ tmp[0] = c;
+ if ( is_armored (tmp) )
+ x->state = c == '-'? STA_first_dash : STA_wait_newline;
+ else {
+ x->state = STA_bypass;
+ return c;
+ }
+ }
+ break;
+ case STA_bypass:
+ return c; /* return here to avoid crc calculation */
+ case STA_wait_newline:
+ if (c == '\n')
+ x->state = STA_wait_dash;
+ break;
+ case STA_wait_dash:
+ x->state = c == '-'? STA_first_dash : STA_wait_newline;
+ break;
+ case STA_first_dash: /* just need for initalization */
+ x->pos = 0;
+ x->state = STA_compare_header;
+ case STA_compare_header:
+ if ( "-----BEGIN PGP SIGNATURE-----"[++x->pos] == c ) {
+ if ( x->pos == 28 )
+ x->state = STA_found_header_wait_newline;
+ }
+ else
+ x->state = c == '\n'? STA_wait_dash : STA_wait_newline;
+ break;
+ case STA_found_header_wait_newline:
+ /* to make CR,LF issues easier we simply allow for white space
+ behind the 5 dashes */
+ if ( c == '\n' )
+ x->state = STA_skip_header_lines;
+ else if ( c != '\r' && c != ' ' && c != '\t' )
+ x->state = STA_wait_dash; /* garbage after the header line */
+ break;
+ case STA_skip_header_lines:
+ /* i.e. wait for one empty line */
+ if ( c == '\n' ) {
+ x->state = STA_read_data;
+ x->crc = CRCINIT;
+ x->val = 0;
+ x->pos = 0;
+ }
+ else if ( c != '\r' && c != ' ' && c != '\t' )
+ x->state = STA_skip_header_lines_non_ws;
+ break;
+ case STA_skip_header_lines_non_ws:
+ /* like above but we already encountered non white space */
+ if ( c == '\n' )
+ x->state = STA_skip_header_lines;
+ break;
+ case STA_read_data:
+ /* fixme: we don't check for the trailing dash lines but rely
+ * on the armor stop characters */
+ if( c == '\n' || c == ' ' || c == '\r' || c == '\t' )
+ break; /* skip all kind of white space */
+
+ if( c == '=' ) { /* pad character: stop */
+ if( x->pos == 1 ) /* in this case val has some value */
+ rval = x->val;
+ x->state = STA_wait_crc;
+ break;
+ }
+
+ {
+ int c2;
+ if( (c = asctobin[(c2=c)]) == 255 ) {
+ log_error(_("invalid radix64 character %02X skipped\n"), c2);
+ break;
+ }
+ }
+
+ switch(x->pos) {
+ case 0:
+ x->val = c << 2;
+ break;
+ case 1:
+ x->val |= (c>>4)&3;
+ rval = x->val;
+ x->val = (c<<4)&0xf0;
+ break;
+ case 2:
+ x->val |= (c>>2)&15;
+ rval = x->val;
+ x->val = (c<<6)&0xc0;
+ break;
+ case 3:
+ x->val |= c&0x3f;
+ rval = x->val;
+ break;
+ }
+ x->pos = (x->pos+1) % 4;
+ break;
+ case STA_wait_crc:
+ if( c == '\n' || c == ' ' || c == '\r' || c == '\t' || c == '=' )
+ break; /* skip ws and pad characters */
+ /* assume that we are at the next line */
+ x->state = STA_read_crc;
+ x->pos = 0;
+ x->mycrc = 0;
+ case STA_read_crc:
+ if( (c = asctobin[c]) == 255 ) {
+ rval = -1; /* ready */
+ if( x->crc != x->mycrc ) {
+ log_info (_("CRC error; %06lX - %06lX\n"),
+ (ulong)x->crc, (ulong)x->mycrc);
+ if ( invalid_crc() )
+ rval = -3;
+ }
+ x->state = STA_ready; /* not sure whether this is correct */
+ break;
+ }
+
+ switch(x->pos) {
+ case 0:
+ x->val = c << 2;
+ break;
+ case 1:
+ x->val |= (c>>4)&3;
+ x->mycrc |= x->val << 16;
+ x->val = (c<<4)&0xf0;
+ break;
+ case 2:
+ x->val |= (c>>2)&15;
+ x->mycrc |= x->val << 8;
+ x->val = (c<<6)&0xc0;
+ break;
+ case 3:
+ x->val |= c&0x3f;
+ x->mycrc |= x->val;
+ break;
+ }
+ x->pos = (x->pos+1) % 4;
+ break;
+ case STA_ready:
+ rval = -1;
+ break;
+ }
+
+ if ( !(rval & ~255) ) { /* compute the CRC */
+ x->crc = (x->crc << 8) ^ crc_table[((x->crc >> 16)&0xff) ^ rval];
+ x->crc &= 0x00ffffff;
+ }
+
+ return rval;
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-21 15:54:09 +0000