static char * size_str( long int l_size );
-/*****************************************************************************
- * OpenPGP functions
- *****************************************************************************/
-
-#define packet_type( c ) ( ( c & 0x3c ) >> 2 ) /* 0x3C = 00111100 */
-#define packet_header_len( c ) ( ( c & 0x03 ) + 1 ) /* number of bytes in a packet header */
-
-static inline int scalar_number( uint8_t *p, int header_len )
-{
- assert( header_len == 1 || header_len == 2 || header_len == 4 );
-
- if( header_len == 1 )
- return( p[0] );
- else if( header_len == 2 )
- return( (p[0] << 8) + p[1] );
- else if( header_len == 4 )
- return( (p[0] << 24) + (p[1] << 16) + (p[2] << 8) + p[3] );
-
- abort(); /* to shut up GCC warning */
-}
-
-/* number of data bytes in a MPI */
-#define mpi_len( mpi ) ( ( scalar_number( mpi, 2 ) + 7 ) / 8 )
-
-/*
- * fill a public_key_packet_t structure from public key packet data
- * verify that it is a version 4 public key packet, using DSA
- */
-static int parse_public_key_packet( public_key_packet_t *p_key, uint8_t *p_buf,
- size_t i_packet_len )
-{
-
- if( i_packet_len > 418 || i_packet_len < 6 )
- return VLC_EGENERIC;
-
- size_t i_read = 0;
-
- p_key->version = *p_buf++; i_read++;
- if( p_key->version != 4 )
- return VLC_EGENERIC;
-
- /* XXX: warn when timestamp is > date ? */
- memcpy( p_key->timestamp, p_buf, 4 ); p_buf += 4; i_read += 4;
-
- p_key->algo = *p_buf++; i_read++;
- if( p_key->algo != PUBLIC_KEY_ALGO_DSA )
- return VLC_EGENERIC;
-
- /* read p */
- if( i_read + 2 > i_packet_len )
- return VLC_EGENERIC;
-
- int i_p_len = mpi_len( p_buf );
-
- if( i_p_len > 128 || i_read + 2 + i_p_len > i_packet_len )
- return VLC_EGENERIC;
-
- memcpy( p_key->p, p_buf, 2+i_p_len );
- p_buf += 2+i_p_len; i_read += 2+i_p_len;
-
- /* read q */
- if( i_read + 2 > i_packet_len )
- return VLC_EGENERIC;
-
- int i_q_len = mpi_len( p_buf );
-
- if( i_q_len > 20 || i_read+2+i_q_len > i_packet_len )
- return VLC_EGENERIC;
-
- memcpy( p_key->q, p_buf, 2+i_q_len );
- p_buf += 2+i_q_len; i_read += 2+i_q_len;
-
- /* read g */
- if( i_read + 2 > i_packet_len )
- return VLC_EGENERIC;
-
- int i_g_len = mpi_len( p_buf );
-
- if( i_g_len > 128 || i_read+2+i_g_len > i_packet_len )
- return VLC_EGENERIC;
-
- memcpy( p_key->g, p_buf, 2+i_g_len );
- p_buf += 2+i_g_len; i_read += 2+i_g_len;
-
- /* read y */
- if( i_read + 2 > i_packet_len )
- return VLC_EGENERIC;
-
- int i_y_len = mpi_len( p_buf );
-
-
- if( i_y_len > 128 || i_read+2+i_y_len > i_packet_len )
- return VLC_EGENERIC;
-
- memcpy( p_key->y, p_buf, 2+i_y_len );
- i_read += 2+i_y_len;
-
- if( i_read != i_packet_len ) /* some extra data eh ? */
- return VLC_EGENERIC;
-
- return VLC_SUCCESS;
-}
-
-static size_t parse_signature_v3_packet( signature_packet_t *p_sig,
- uint8_t *p_buf, size_t i_sig_len )
-{
- size_t i_read = 1; /* we already read the version byte */
-
- if( i_sig_len < 19 ) /* signature is at least 19 bytes + the 2 MPIs */
- return 0;
-
- p_sig->specific.v3.hashed_data_len = *p_buf++; i_read++;
- if( p_sig->specific.v3.hashed_data_len != 5 )
- return 0;
-
- p_sig->type = *p_buf++; i_read++;
-
- memcpy( p_sig->specific.v3.timestamp, p_buf, 4 );
- p_buf += 4; i_read += 4;
-
- memcpy( p_sig->issuer_longid, p_buf, 8 );
- p_buf += 8; i_read += 8;
-
- p_sig->public_key_algo = *p_buf++; i_read++;
-
- p_sig->digest_algo = *p_buf++; i_read++;
-
- p_sig->hash_verification[0] = *p_buf++; i_read++;
- p_sig->hash_verification[1] = *p_buf++; i_read++;
-
- assert( i_read == 19 );
-
- return i_read;
-}
-
-/*
- * fill a signature_packet_v4_t from signature packet data
- * verify that it was used with a DSA public key, using SHA-1 digest
- */
-static size_t parse_signature_v4_packet( signature_packet_t *p_sig,
- uint8_t *p_buf, size_t i_sig_len )
-{
- size_t i_read = 1; /* we already read the version byte */
-
- if( i_sig_len < 10 ) /* signature is at least 10 bytes + the 2 MPIs */
- return 0;
-
- p_sig->type = *p_buf++; i_read++;
-
- p_sig->public_key_algo = *p_buf++; i_read++;
-
- p_sig->digest_algo = *p_buf++; i_read++;
-
- memcpy( p_sig->specific.v4.hashed_data_len, p_buf, 2 );
- p_buf += 2; i_read += 2;
-
- size_t i_hashed_data_len =
- scalar_number( p_sig->specific.v4.hashed_data_len, 2 );
- i_read += i_hashed_data_len;
- if( i_read + 4 > i_sig_len )
- return 0;
-
- p_sig->specific.v4.hashed_data = (uint8_t*) malloc( i_hashed_data_len );
- if( !p_sig->specific.v4.hashed_data )
- return 0;
- memcpy( p_sig->specific.v4.hashed_data, p_buf, i_hashed_data_len );
- p_buf += i_hashed_data_len;
-
- memcpy( p_sig->specific.v4.unhashed_data_len, p_buf, 2 );
- p_buf += 2; i_read += 2;
-
- size_t i_unhashed_data_len =
- scalar_number( p_sig->specific.v4.unhashed_data_len, 2 );
- i_read += i_unhashed_data_len;
- if( i_read + 2 > i_sig_len )
- return 0;
-
- p_sig->specific.v4.unhashed_data = (uint8_t*) malloc( i_unhashed_data_len );
- if( !p_sig->specific.v4.unhashed_data )
- return 0;
-
- memcpy( p_sig->specific.v4.unhashed_data, p_buf, i_unhashed_data_len );
- p_buf += i_unhashed_data_len;
-
- memcpy( p_sig->hash_verification, p_buf, 2 );
- p_buf += 2; i_read += 2;
-
- uint8_t *p, *max_pos;
- p = p_sig->specific.v4.unhashed_data;
- max_pos = p + scalar_number( p_sig->specific.v4.unhashed_data_len, 2 );
-
- for( ;; )
- {
- if( p > max_pos )
- return 0;
-
- size_t i_subpacket_len;
- if( *p < 192 )
- {
- if( p + 1 > max_pos )
- return 0;
- i_subpacket_len = *p++;
- }
- else if( *p < 255 )
- {
- if( p + 2 > max_pos )
- return 0;
- i_subpacket_len = (*p++ - 192) << 8;
- i_subpacket_len += *p++ + 192;
- }
- else
- {
- if( p + 4 > max_pos )
- return 0;
- i_subpacket_len = *++p << 24;
- i_subpacket_len += *++p << 16;
- i_subpacket_len += *++p << 8;
- i_subpacket_len += *++p;
- }
-
- if( *p == ISSUER_SUBPACKET )
- {
- if( p + 9 > max_pos )
- return 0;
-
- memcpy( &p_sig->issuer_longid, p+1, 8 );
-
- return i_read;
- }
-
- p += i_subpacket_len;
- }
-}
-
-static int parse_signature_packet( signature_packet_t *p_sig,
- uint8_t *p_buf, size_t i_sig_len )
-{
- if( !i_sig_len ) /* 1st sanity check, we need at least the version */
- return VLC_EGENERIC;
-
- p_sig->version = *p_buf++;
-
- size_t i_read;
- switch( p_sig->version )
- {
- case 3:
- i_read = parse_signature_v3_packet( p_sig, p_buf, i_sig_len );
- break;
- case 4:
- p_sig->specific.v4.hashed_data = NULL;
- p_sig->specific.v4.unhashed_data = NULL;
- i_read = parse_signature_v4_packet( p_sig, p_buf, i_sig_len );
- break;
- default:
- return VLC_EGENERIC;
- }
-
- if( i_read == 0 ) /* signature packet parsing has failed */
- goto error;
-
- if( p_sig->public_key_algo != PUBLIC_KEY_ALGO_DSA )
- goto error;
-
- if( p_sig->digest_algo != DIGEST_ALGO_SHA1 )
- goto error;
-
- switch( p_sig->type )
- {
- case BINARY_SIGNATURE:
- case TEXT_SIGNATURE:
- case GENERIC_KEY_SIGNATURE:
- case PERSONA_KEY_SIGNATURE:
- case CASUAL_KEY_SIGNATURE:
- case POSITIVE_KEY_SIGNATURE:
- break;
- default:
- goto error;
- }
-
- p_buf--; /* rewind to the version byte */
- p_buf += i_read;
-
- if( i_read + 2 > i_sig_len )
- goto error;
-
- size_t i_r_len = mpi_len( p_buf ); i_read += 2;
- if( i_read + i_r_len > i_sig_len || i_r_len > 20 )
- goto error;
-
- memcpy( p_sig->r, p_buf, 2 + i_r_len );
- p_buf += 2 + i_r_len;
- i_read += i_r_len;
-
- if( i_read + 2 > i_sig_len )
- goto error;
-
- size_t i_s_len = mpi_len( p_buf ); i_read += 2;
- if( i_read + i_s_len > i_sig_len || i_s_len > 20 )
- goto error;
-
- memcpy( p_sig->s, p_buf, 2 + i_s_len );
- p_buf += 2 + i_s_len;
- i_read += i_s_len;
-
- assert( i_read == i_sig_len );
- if( i_read < i_sig_len ) /* some extra data, hm ? */
- goto error;
-
- return VLC_SUCCESS;
-
-error:
-
- if( p_sig->version == 4 )
- {
- free( p_sig->specific.v4.hashed_data );
- free( p_sig->specific.v4.unhashed_data );
- }
-
- return VLC_EGENERIC;
-}
-
-/*
- * crc_octets() was lamely copied from rfc 2440
- * Copyright (C) The Internet Society (1998). All Rights Reserved.
- */
-#define CRC24_INIT 0xB704CEL
-#define CRC24_POLY 0x1864CFBL
-
-static long crc_octets( uint8_t *octets, size_t len )
-{
- long crc = CRC24_INIT;
- int i;
- while (len--)
- {
- crc ^= (*octets++) << 16;
- for (i = 0; i < 8; i++)
- {
- crc <<= 1;
- if (crc & 0x1000000)
- crc ^= CRC24_POLY;
- }
- }
- return crc & 0xFFFFFFL;
-}
-
-/*
- * Transform an armored document in binary format
- * Used on public keys and signatures
- */
-static int pgp_unarmor( char *p_ibuf, size_t i_ibuf_len,
- uint8_t *p_obuf, size_t i_obuf_len )
-{
- char *p_ipos = p_ibuf;
- uint8_t *p_opos = p_obuf;
- int i_end = 0;
- int i_header_skipped = 0;
-
- while( !i_end && p_ipos < p_ibuf + i_ibuf_len && *p_ipos != '=' )
- {
- if( *p_ipos == '\r' || *p_ipos == '\n' )
- {
- p_ipos++;
- continue;
- }
-
- size_t i_line_len = strcspn( p_ipos, "\r\n" );
- if( i_line_len == 0 )
- continue;
-
- if( !i_header_skipped )
- {
- if( !strncmp( p_ipos, "-----BEGIN PGP", 14 ) )
- i_header_skipped = 1;
-
- p_ipos += i_line_len + 1;
- continue;
- }
-
- if( !strncmp( p_ipos, "Version:", 8 ) )
- {
- p_ipos += i_line_len + 1;
- continue;
- }
-
- if( p_ipos[i_line_len - 1] == '=' )
- {
- i_end = 1;
- p_ipos[i_line_len - 1] = '\0';
- }
- else
- p_ipos[i_line_len] = '\0';
-
- p_opos += vlc_b64_decode_binary_to_buffer( p_opos,
- p_obuf - p_opos + i_obuf_len, p_ipos );
- p_ipos += i_line_len + 1;
- }
-
- /* XXX: the CRC is OPTIONAL, really require it ? */
- if( p_ipos + 5 > p_ibuf + i_ibuf_len || *p_ipos++ != '=' )
- return 0;
-
- uint8_t p_crc[3];
- if( vlc_b64_decode_binary_to_buffer( p_crc, 3, p_ipos ) != 3 )
- return 0;
-
- long l_crc = crc_octets( p_obuf, p_opos - p_obuf );
- long l_crc2 = ( 0 << 24 ) + ( p_crc[0] << 16 ) + ( p_crc[1] << 8 ) + p_crc[2];
-
- return l_crc2 == l_crc ? p_opos - p_obuf : 0;
-}
-
-/*
- * Download the signature associated to a document or a binary file.
- * We're given the file's url, we just append ".asc" to it and download
- */
-static int download_signature( vlc_object_t *p_this,
- signature_packet_t *p_sig,
- const char *psz_url )
-{
- char *psz_sig = (char*) malloc( strlen( psz_url ) + 4 + 1 ); /* ".asc" + \0 */
- if( !psz_sig )
- return VLC_ENOMEM;
-
- strcpy( psz_sig, psz_url );
- strcat( psz_sig, ".asc" );
-
- stream_t *p_stream = stream_UrlNew( p_this, psz_sig );
- free( psz_sig );
-
- if( !p_stream )
- return VLC_ENOMEM;
-
- int64_t i_size = stream_Size( p_stream );
-
- msg_Dbg( p_this, "Downloading signature (%"PRId64" bytes)", i_size );
- uint8_t *p_buf = (uint8_t*)malloc( i_size );
- if( !p_buf )
- {
- stream_Delete( p_stream );
- return VLC_ENOMEM;
- }
-
- int i_read = stream_Read( p_stream, p_buf, (int)i_size );
-
- stream_Delete( p_stream );
-
- if( i_read != (int)i_size )
- {
- msg_Dbg( p_this,
- "Couldn't download full signature (only %d bytes)", i_read );
- free( p_buf );
- return VLC_EGENERIC;
- }
-
- if( (uint8_t)*p_buf < 0x80 ) /* ASCII */
- {
- msg_Dbg( p_this, "Unarmoring signature" );
-
- uint8_t* p_unarmored = (uint8_t*) malloc( ( i_size * 3 ) / 4 + 1 );
- if( !p_unarmored )
- {
- free( p_buf );
- return VLC_EGENERIC;
- }
-
- int i_bytes = pgp_unarmor( (char*)p_buf, i_size, p_unarmored, i_size );
- free( p_buf );
-
- p_buf = p_unarmored;
- i_size = i_bytes;
-
- if( i_bytes < 2 )
- {
- free( p_buf );
- msg_Dbg( p_this, "Unarmoring failed : corrupted signature ?" );
- return VLC_EGENERIC;
- }
- }
-
- if( packet_type( *p_buf ) != SIGNATURE_PACKET )
- {
- free( p_buf );
- msg_Dbg( p_this, "Not a signature: %d", *p_buf );
- return VLC_EGENERIC;
- }
-
- size_t i_header_len = packet_header_len( *p_buf );
- if( ( i_header_len != 1 && i_header_len != 2 && i_header_len != 4 ) ||
- i_header_len + 1 > (size_t)i_size )
- {
- free( p_buf );
- msg_Dbg( p_this, "Invalid signature packet header" );
- return VLC_EGENERIC;
- }
-
- size_t i_len = scalar_number( p_buf+1, i_header_len );
- if( i_len + i_header_len + 1 != (size_t)i_size )
- {
- free( p_buf );
- msg_Dbg( p_this, "Invalid signature packet" );
- return VLC_EGENERIC;
- }
-
- int i_ret = parse_signature_packet( p_sig, p_buf+1+i_header_len, i_len );
- free( p_buf );
- if( i_ret != VLC_SUCCESS )
- {
- msg_Dbg( p_this, "Couldn't parse signature" );
- return i_ret;
- }
-
- if( p_sig->type != BINARY_SIGNATURE && p_sig->type != TEXT_SIGNATURE )
- {
- msg_Dbg( p_this, "Invalid signature type: %d", p_sig->type );
- if( p_sig->version == 4 )
- {
- free( p_sig->specific.v4.hashed_data );
- free( p_sig->specific.v4.unhashed_data );
- }
- return VLC_EGENERIC;
- }
-
- return VLC_SUCCESS;
-}
-
-/*
- * Verify an OpenPGP signature made on some SHA-1 hash, with some DSA public key
- */
-static int verify_signature( uint8_t *p_r, uint8_t *p_s,
- public_key_packet_t *p_key, uint8_t *p_hash )
-{
- /* the data to be verified (a SHA-1 hash) */
- const char *hash_sexp_s = "(data(flags raw)(value %m))";
- /* the public key */
- const char *key_sexp_s = "(public-key(dsa(p %m)(q %m)(g %m)(y %m)))";
- /* the signature */
- const char *sig_sexp_s = "(sig-val(dsa(r %m )(s %m )))";
-
- size_t erroff;
- gcry_mpi_t p, q, g, y, r, s, hash;
- p = q = g = y = r = s = hash = NULL;
- gcry_sexp_t key_sexp, hash_sexp, sig_sexp;
- key_sexp = hash_sexp = sig_sexp = NULL;
-
- int i_p_len = mpi_len( p_key->p );
- int i_q_len = mpi_len( p_key->q );
- int i_g_len = mpi_len( p_key->g );
- int i_y_len = mpi_len( p_key->y );
- if( gcry_mpi_scan( &p, GCRYMPI_FMT_USG, p_key->p + 2, i_p_len, NULL ) ||
- gcry_mpi_scan( &q, GCRYMPI_FMT_USG, p_key->q + 2, i_q_len, NULL ) ||
- gcry_mpi_scan( &g, GCRYMPI_FMT_USG, p_key->g + 2, i_g_len, NULL ) ||
- gcry_mpi_scan( &y, GCRYMPI_FMT_USG, p_key->y + 2, i_y_len, NULL ) ||
- gcry_sexp_build( &key_sexp, &erroff, key_sexp_s, p, q, g, y ) )
- goto problem;
-
- int i_r_len = mpi_len( p_r );
- int i_s_len = mpi_len( p_s );
- if( gcry_mpi_scan( &r, GCRYMPI_FMT_USG, p_r + 2, i_r_len, NULL ) ||
- gcry_mpi_scan( &s, GCRYMPI_FMT_USG, p_s + 2, i_s_len, NULL ) ||
- gcry_sexp_build( &sig_sexp, &erroff, sig_sexp_s, r, s ) )
- goto problem;
-
- int i_hash_len = 20;
- if( gcry_mpi_scan( &hash, GCRYMPI_FMT_USG, p_hash, i_hash_len, NULL ) ||
- gcry_sexp_build( &hash_sexp, &erroff, hash_sexp_s, hash ) )
- goto problem;
-
- if( gcry_pk_verify( sig_sexp, hash_sexp, key_sexp ) )
- goto problem;
-
- return VLC_SUCCESS;
-
-problem:
- if( p ) gcry_mpi_release( p );
- if( q ) gcry_mpi_release( q );
- if( g ) gcry_mpi_release( g );
- if( y ) gcry_mpi_release( y );
- if( r ) gcry_mpi_release( r );
- if( s ) gcry_mpi_release( s );
- if( hash ) gcry_mpi_release( hash );
- if( key_sexp ) gcry_sexp_release( key_sexp );
- if( sig_sexp ) gcry_sexp_release( sig_sexp );
- if( hash_sexp ) gcry_sexp_release( hash_sexp );
- return VLC_EGENERIC;
-}
-
-/*
- * fill a public_key_t with public key data, including:
- * * public key packet
- * * signature packet issued by key which long id is p_sig_issuer
- * * user id packet
- */
-static int parse_public_key( const uint8_t *p_key_data, size_t i_key_len,
- public_key_t *p_key, const uint8_t *p_sig_issuer )
-{
- uint8_t *pos = (uint8_t*) p_key_data;
- uint8_t *max_pos = pos + i_key_len;
-
- int i_status = 0;
-#define PUBLIC_KEY_FOUND 0x01
-#define USER_ID_FOUND 0x02
-#define SIGNATURE_FOUND 0X04
-
- uint8_t *p_key_unarmored = NULL;
-
- p_key->psz_username = NULL;
- p_key->sig.specific.v4.hashed_data = NULL;
- p_key->sig.specific.v4.unhashed_data = NULL;
-
- if( !( *pos & 0x80 ) )
- { /* first byte is ASCII, unarmoring */
- p_key_unarmored = (uint8_t*)malloc( i_key_len );
- if( !p_key_unarmored )
- return VLC_ENOMEM;
- int i_len = pgp_unarmor( (char*)p_key_data, i_key_len,
- p_key_unarmored, i_key_len );
-
- if( i_len == 0 )
- goto error;
-
- pos = p_key_unarmored;
- max_pos = pos + i_len;
- }
-
- while( pos < max_pos )
- {
- if( !(*pos & 0x80) || *pos & 0x40 )
- goto error;
-
- int i_type = packet_type( *pos );
-
- int i_header_len = packet_header_len( *pos++ );
- if( pos + i_header_len > max_pos ||
- ( i_header_len != 1 && i_header_len != 2 && i_header_len != 4 ) )
- goto error;
-
- int i_packet_len = scalar_number( pos, i_header_len );
- pos += i_header_len;
-
- if( pos + i_packet_len > max_pos )
- goto error;
-
- switch( i_type )
- {
- case PUBLIC_KEY_PACKET:
- i_status |= PUBLIC_KEY_FOUND;
- if( parse_public_key_packet( &p_key->key, pos, i_packet_len ) != VLC_SUCCESS )
- goto error;
- break;
-
- case SIGNATURE_PACKET: /* we accept only v4 signatures here */
- if( i_status & SIGNATURE_FOUND || !p_sig_issuer )
- break;
- int i_ret = parse_signature_packet( &p_key->sig, pos,
- i_packet_len );
- if( i_ret == VLC_SUCCESS )
- {
- if( p_key->sig.version != 4 )
- break;
- if( memcmp( p_key->sig.issuer_longid, p_sig_issuer, 8 ) )
- {
- free( p_key->sig.specific.v4.hashed_data );
- free( p_key->sig.specific.v4.unhashed_data );
- p_key->sig.specific.v4.hashed_data = NULL;
- p_key->sig.specific.v4.unhashed_data = NULL;
- break;
- }
- i_status |= SIGNATURE_FOUND;
- }
- break;
-
- case USER_ID_PACKET:
- if( p_key->psz_username ) /* save only the first User ID */
- break;
- i_status |= USER_ID_FOUND;
- p_key->psz_username = (uint8_t*)malloc( i_packet_len + 1);
- if( !p_key->psz_username )
- goto error;
-
- memcpy( p_key->psz_username, pos, i_packet_len );
- p_key->psz_username[i_packet_len] = '\0';
- break;
-
- default:
- break;
- }
- pos += i_packet_len;
- }
- free( p_key_unarmored );
-
- if( !( i_status & ( PUBLIC_KEY_FOUND | USER_ID_FOUND ) ) )
- return VLC_EGENERIC;
-
- if( p_sig_issuer && !( i_status & SIGNATURE_FOUND ) )
- return VLC_EGENERIC;
-
- return VLC_SUCCESS;
-
-error:
- if( p_key->sig.version == 4 )
- {
- free( p_key->sig.specific.v4.hashed_data );
- free( p_key->sig.specific.v4.unhashed_data );
- }
- free( p_key->psz_username );
- free( p_key_unarmored );
- return VLC_EGENERIC;
-}
-
-/*
- * return a sha1 hash of a file
- */
-static uint8_t *hash_sha1_from_file( const char *psz_file,
- signature_packet_t *p_sig )
-{
- if( p_sig->type != BINARY_SIGNATURE && p_sig->type != TEXT_SIGNATURE )
- return NULL;
-
- FILE *f = utf8_fopen( psz_file, "r" );
- if( !f )
- return NULL;
-
- uint8_t buffer[4096];
-
- gcry_md_hd_t hd;
- if( gcry_md_open( &hd, GCRY_MD_SHA1, 0 ) )
- {
- fclose( f );
- return NULL;
- }
-
- size_t i_read;
- while( ( i_read = fread( buffer, 1, sizeof(buffer), f ) ) > 0 )
- gcry_md_write( hd, buffer, i_read );
-
- if( p_sig->version == 3 )
- {
- gcry_md_putc( hd, p_sig->type );
- gcry_md_write( hd, &p_sig->specific.v3.timestamp, 4 );
- }
- else if( p_sig->version == 4 )
- {
- gcry_md_putc( hd, p_sig->version );
- gcry_md_putc( hd, p_sig->type );
- gcry_md_putc( hd, p_sig->public_key_algo );
- gcry_md_putc( hd, p_sig->digest_algo );
- gcry_md_write( hd, p_sig->specific.v4.hashed_data_len, 2 );
- size_t i_len = scalar_number( p_sig->specific.v4.hashed_data_len, 2 );
- gcry_md_write( hd, p_sig->specific.v4.hashed_data, i_len );
-
- gcry_md_putc( hd, 0x04 );
- gcry_md_putc( hd, 0xFF );
-
- i_len += 6; /* hashed data + 6 bytes header */
-
- gcry_md_putc( hd, (i_len >> 24) & 0xff );
- gcry_md_putc( hd, (i_len >> 16) & 0xff );
- gcry_md_putc( hd, (i_len >> 8) & 0xff );
- gcry_md_putc( hd, (i_len) & 0xff );
- }
- else
- { /* RFC 4880 only tells about versions 3 and 4 */
- gcry_md_close( hd );
- return NULL;
- }
-
- fclose( f );
- gcry_md_final( hd );
-
- uint8_t *p_tmp = (uint8_t*) gcry_md_read( hd, GCRY_MD_SHA1);
- uint8_t *p_hash = malloc( 20 );
- if( p_hash )
- memcpy( p_hash, p_tmp, 20 );
- gcry_md_close( hd );
- return p_hash;
-}
-
-/*
- * download a public key (the last one) from videolan server, and parse it
- */
-static public_key_t *download_key( vlc_object_t *p_this,
- const uint8_t *p_longid, const uint8_t *p_signature_issuer )
-{
- char *psz_url;
- if( asprintf( &psz_url, "http://download.videolan.org/pub/keys/%.2X%.2X%.2X%.2X%.2X%.2X%.2X%.2X.asc",
- p_longid[0], p_longid[1], p_longid[2], p_longid[3],
- p_longid[4], p_longid[5], p_longid[6], p_longid[7] ) == -1 )
- return NULL;
-
- stream_t *p_stream = stream_UrlNew( p_this, psz_url );
- free( psz_url );
- if( !p_stream )
- return NULL;
-
- int64_t i_size = stream_Size( p_stream );
- if( i_size < 0 )
- {
- stream_Delete( p_stream );
- return NULL;
- }
-
- uint8_t *p_buf = (uint8_t*)malloc( i_size );
- if( !p_buf )
- {
- stream_Delete( p_stream );
- return NULL;
- }
-
- int i_read = stream_Read( p_stream, p_buf, (int)i_size );
- stream_Delete( p_stream );
-
- if( i_read != (int)i_size )
- {
- msg_Dbg( p_this, "Couldn't read full GPG key" );
- free( p_buf );
- return NULL;
- }
-
- public_key_t *p_pkey = (public_key_t*) malloc( sizeof( public_key_t ) );
- if( !p_pkey )
- {
- free( p_buf );
- return NULL;
- }
-
- memcpy( p_pkey->longid, p_longid, 8 );
-
- int i_error = parse_public_key( p_buf, i_read, p_pkey, p_signature_issuer );
- free( p_buf );
-
- if( i_error != VLC_SUCCESS )
- {
- msg_Dbg( p_this, "Couldn't parse GPG key" );
- free( p_pkey );
- return NULL;
- }
-
- return p_pkey;
-}
-
-/*
- * Generate a SHA1 hash on a public key, to verify a signature made on that hash
- * Note that we need the signature (v4) to compute the hash
- */
-static uint8_t *key_sign_hash( public_key_t *p_pkey )
-{
- if( p_pkey->sig.version != 4 )
- return NULL;
-
- if( p_pkey->sig.type < GENERIC_KEY_SIGNATURE ||
- p_pkey->sig.type > POSITIVE_KEY_SIGNATURE )
- return NULL;
-
- gcry_error_t error = 0;
- gcry_md_hd_t hd;
-
- error = gcry_md_open( &hd, GCRY_MD_SHA1, 0 );
- if( error )
- return NULL;
-
- gcry_md_putc( hd, 0x99 );
-
- size_t i_p_len = mpi_len( p_pkey->key.p );
- size_t i_g_len = mpi_len( p_pkey->key.g );
- size_t i_q_len = mpi_len( p_pkey->key.q );
- size_t i_y_len = mpi_len( p_pkey->key.y );
-
- size_t i_size = 6 + 2*4 + i_p_len + i_g_len + i_q_len + i_y_len;
-
- gcry_md_putc( hd, (i_size >> 8) & 0xff );
- gcry_md_putc( hd, i_size & 0xff );
-
- gcry_md_putc( hd, p_pkey->key.version );
- gcry_md_write( hd, p_pkey->key.timestamp, 4 );
- gcry_md_putc( hd, p_pkey->key.algo );
-
- gcry_md_write( hd, (uint8_t*)&p_pkey->key.p, 2 );
- gcry_md_write( hd, (uint8_t*)&p_pkey->key.p + 2, i_p_len );
-
- gcry_md_write( hd, (uint8_t*)&p_pkey->key.q, 2 );
- gcry_md_write( hd, (uint8_t*)&p_pkey->key.q + 2, i_q_len );
-
- gcry_md_write( hd, (uint8_t*)&p_pkey->key.g, 2 );
- gcry_md_write( hd, (uint8_t*)&p_pkey->key.g + 2, i_g_len );
-
- gcry_md_write( hd, (uint8_t*)&p_pkey->key.y, 2 );
- gcry_md_write( hd, (uint8_t*)&p_pkey->key.y + 2, i_y_len );
-
- gcry_md_putc( hd, 0xb4 );
-
- size_t i_len = strlen((char*)p_pkey->psz_username);
-
- gcry_md_putc( hd, (i_len >> 24) & 0xff );
- gcry_md_putc( hd, (i_len >> 16) & 0xff );
- gcry_md_putc( hd, (i_len >> 8) & 0xff );
- gcry_md_putc( hd, (i_len) & 0xff );
-
- gcry_md_write( hd, p_pkey->psz_username, i_len );
-
- size_t i_hashed_data_len =
- scalar_number( p_pkey->sig.specific.v4.hashed_data_len, 2 );
-
- gcry_md_putc( hd, p_pkey->sig.version );
- gcry_md_putc( hd, p_pkey->sig.type );
- gcry_md_putc( hd, p_pkey->sig.public_key_algo );
- gcry_md_putc( hd, p_pkey->sig.digest_algo );
- gcry_md_write( hd, p_pkey->sig.specific.v4.hashed_data_len, 2 );
- gcry_md_write( hd, p_pkey->sig.specific.v4.hashed_data, i_hashed_data_len );
-
- gcry_md_putc( hd, 0x04 );
- gcry_md_putc( hd, 0xff );
-
- i_hashed_data_len += 6; /* hashed data + 6 bytes header */
-
- gcry_md_putc( hd, (i_hashed_data_len >> 24) & 0xff );
- gcry_md_putc( hd, (i_hashed_data_len >> 16) & 0xff );
- gcry_md_putc( hd, (i_hashed_data_len >> 8) & 0xff );
- gcry_md_putc( hd, (i_hashed_data_len) & 0xff );
-
- gcry_md_final( hd );
-
- uint8_t *p_tmp = gcry_md_read( hd, GCRY_MD_SHA1 );
-
- if( !p_tmp ||
- p_tmp[0] != p_pkey->sig.hash_verification[0] ||
- p_tmp[1] != p_pkey->sig.hash_verification[1] )
- {
- gcry_md_close( hd );
- return NULL;
- }
-
- uint8_t *p_hash = malloc( 20 );
- if( p_hash )
- memcpy( p_hash, p_tmp, 20 );
- gcry_md_close( hd );
- return p_hash;
-}
-
/*****************************************************************************
* Update_t functions
goto error;
}
- uint8_t *p_hash = key_sign_hash( p_new_pkey );
+ uint8_t *p_hash = hash_sha1_from_public_key( p_new_pkey );
if( !p_hash )
{
msg_Err( p_update->p_libvlc, "Failed to hash signature" );
}
}
- gcry_md_hd_t hd;
- if( gcry_md_open( &hd, GCRY_MD_SHA1, 0 ) )
- goto error_hd;
-
- gcry_md_write( hd, psz_version_line, strlen( psz_version_line ) );
- FREENULL( psz_version_line );
- if( sign.type == TEXT_SIGNATURE )
- gcry_md_putc( hd, '\r' );
- gcry_md_putc( hd, '\n' );
- gcry_md_write( hd, p_update->release.psz_url,
- strlen( p_update->release.psz_url ) );
- if( sign.type == TEXT_SIGNATURE )
- gcry_md_putc( hd, '\r' );
- gcry_md_putc( hd, '\n' );
-
- char *psz_desc = p_update->release.psz_desc;
- while( *psz_desc )
+ /* FIXME : read the status file all at once instead of line per line */
+ char *psz_text;
+ if( asprintf( &psz_text, "%s\n%s\n%s", psz_version_line,
+ p_update->release.psz_url, p_update->release.psz_desc ) == -1 )
{
- size_t i_len = strcspn( psz_desc, "\r\n" );
- if( !i_len )
- break;
-
- gcry_md_write( hd, psz_desc, i_len );
- if( sign.type == TEXT_SIGNATURE )
- gcry_md_putc( hd, '\r' );
- gcry_md_putc( hd, '\n' );
-
- psz_desc += i_len;
- while( *psz_desc == '\r' || *psz_desc == '\n' )
- psz_desc++;
+ goto error;
}
+ FREENULL( psz_version_line );
- if( sign.version == 3 )
- {
- gcry_md_putc( hd, sign.type );
- gcry_md_write( hd, &sign.specific.v3.timestamp, 4 );
- }
- else if( sign.version == 4 )
+ uint8_t *p_hash = hash_sha1_from_text( psz_text, &sign );
+ if( !p_hash )
{
- gcry_md_putc( hd, sign.version );
- gcry_md_putc( hd, sign.type );
- gcry_md_putc( hd, sign.public_key_algo );
- gcry_md_putc( hd, sign.digest_algo );
- gcry_md_write( hd, sign.specific.v4.hashed_data_len, 2 );
- size_t i_len = scalar_number( sign.specific.v4.hashed_data_len, 2 );
- gcry_md_write( hd, sign.specific.v4.hashed_data, i_len );
- gcry_md_putc( hd, 0x04 );
- gcry_md_putc( hd, 0xFF );
-
- i_len += 6; /* hashed data + 6 bytes header */
-
- gcry_md_putc( hd, (i_len >> 24) & 0xff );
- gcry_md_putc( hd, (i_len >> 16) & 0xff );
- gcry_md_putc( hd, (i_len >> 8) & 0xff );
- gcry_md_putc( hd, (i_len) & 0xff );
- }
- else
- { /* RFC 4880 only tells about versions 3 and 4 */
- msg_Warn( p_update->p_libvlc, "Invalid signature version %d",
- sign.version);
- goto error_hd;
+ msg_Warn( p_update->p_libvlc, "Can't compute SHA1 hash for status file" );
+ goto error;
}
- gcry_md_final( hd );
-
- uint8_t *p_hash = gcry_md_read( hd, GCRY_MD_SHA1 );
-
- if( p_hash[0] != sign.hash_verification[0] ||
+ else if( p_hash[0] != sign.hash_verification[0] ||
p_hash[1] != sign.hash_verification[1] )
{
msg_Warn( p_update->p_libvlc, "Bad SHA1 hash for status file" );
- goto error_hd;
+ goto error;
}
- if( verify_signature( sign.r, sign.s, &p_update->p_pkey->key, p_hash )
+ else if( verify_signature( sign.r, sign.s, &p_update->p_pkey->key, p_hash )
!= VLC_SUCCESS )
{
msg_Err( p_update->p_libvlc, "BAD SIGNATURE for status file" );
- goto error_hd;
+ goto error;
}
+
else
{
msg_Info( p_update->p_libvlc, "Status file authenticated" );
- gcry_md_close( hd );
return true;
}
-error_hd:
- gcry_md_close( hd );
error:
if( p_stream )
stream_Delete( p_stream );
return i_retval == -1 ? NULL : psz_tmp;
}
-void update_WaitDownload( update_t *p_update )
-{
- if( p_update->p_download )
- {
- vlc_thread_join( p_update->p_download );
- vlc_object_release( p_update->p_download );
- p_update->p_download = NULL;
- }
-}
-
static void* update_DownloadReal( vlc_object_t *p_this );
/**
free( p_udt->psz_destination );
p_udt->p_update->p_download = NULL;
- vlc_object_release( p_udt );
vlc_restorecancel( canc );
return NULL;
}
return false;
}
-void update_WaitDownload( update_t *p_update )
-{
- (void)p_update;
-}
-
void update_Download( update_t *p_update, const char *psz_destdir )
{
(void)p_update; (void)psz_destdir;
--- /dev/null
+/*****************************************************************************
+ * update_crypto.c: DSA/SHA1 related functions used for updating
+ *****************************************************************************
+ * Copyright © 2008-2009 the VideoLAN team
+ * $Id$
+ *
+ * Authors: Rafaël Carré <funman@videolanorg>
+ *
+ * This program 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 release 2 of the License, or
+ * (at your option) any later release.
+ *
+ * This program 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., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
+ *****************************************************************************/
+
+/**
+ * \file
+ * This file contains functions related to OpenPGP in VLC update management
+ */
+
+/*****************************************************************************
+ * Preamble
+ *****************************************************************************/
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <gcrypt.h>
+#include <assert.h>
+
+#include "vlc_common.h"
+#include <vlc_stream.h>
+#include <vlc_strings.h>
+#include <vlc_charset.h>
+
+#include "update.h"
+
+
+/*****************************************************************************
+ * OpenPGP functions
+ *****************************************************************************/
+
+#define packet_type( c ) ( ( c & 0x3c ) >> 2 ) /* 0x3C = 00111100 */
+#define packet_header_len( c ) ( ( c & 0x03 ) + 1 ) /* number of bytes in a packet header */
+
+
+static inline int scalar_number( uint8_t *p, int header_len )
+{
+ assert( header_len == 1 || header_len == 2 || header_len == 4 );
+
+ if( header_len == 1 )
+ return( p[0] );
+ else if( header_len == 2 )
+ return( (p[0] << 8) + p[1] );
+ else if( header_len == 4 )
+ return( (p[0] << 24) + (p[1] << 16) + (p[2] << 8) + p[3] );
+ else
+ abort();
+}
+
+
+/* number of data bytes in a MPI */
+#define mpi_len( mpi ) ( ( scalar_number( mpi, 2 ) + 7 ) / 8 )
+
+
+/*
+ * fill a public_key_packet_t structure from public key packet data
+ * verify that it is a version 4 public key packet, using DSA
+ */
+static int parse_public_key_packet( public_key_packet_t *p_key, uint8_t *p_buf,
+ size_t i_packet_len )
+{
+
+ if( i_packet_len > 418 || i_packet_len < 6 )
+ return VLC_EGENERIC;
+
+ size_t i_read = 0;
+
+ p_key->version = *p_buf++; i_read++;
+ if( p_key->version != 4 )
+ return VLC_EGENERIC;
+
+ /* XXX: warn when timestamp is > date ? */
+ memcpy( p_key->timestamp, p_buf, 4 ); p_buf += 4; i_read += 4;
+
+ p_key->algo = *p_buf++; i_read++;
+ if( p_key->algo != PUBLIC_KEY_ALGO_DSA )
+ return VLC_EGENERIC;
+
+ /* read p */
+ if( i_read + 2 > i_packet_len )
+ return VLC_EGENERIC;
+
+ int i_p_len = mpi_len( p_buf );
+
+ if( i_p_len > 128 || i_read + 2 + i_p_len > i_packet_len )
+ return VLC_EGENERIC;
+
+ memcpy( p_key->p, p_buf, 2+i_p_len );
+ p_buf += 2+i_p_len; i_read += 2+i_p_len;
+
+ /* read q */
+ if( i_read + 2 > i_packet_len )
+ return VLC_EGENERIC;
+
+ int i_q_len = mpi_len( p_buf );
+
+ if( i_q_len > 20 || i_read+2+i_q_len > i_packet_len )
+ return VLC_EGENERIC;
+
+ memcpy( p_key->q, p_buf, 2+i_q_len );
+ p_buf += 2+i_q_len; i_read += 2+i_q_len;
+
+ /* read g */
+ if( i_read + 2 > i_packet_len )
+ return VLC_EGENERIC;
+
+ int i_g_len = mpi_len( p_buf );
+
+ if( i_g_len > 128 || i_read+2+i_g_len > i_packet_len )
+ return VLC_EGENERIC;
+
+ memcpy( p_key->g, p_buf, 2+i_g_len );
+ p_buf += 2+i_g_len; i_read += 2+i_g_len;
+
+ /* read y */
+ if( i_read + 2 > i_packet_len )
+ return VLC_EGENERIC;
+
+ int i_y_len = mpi_len( p_buf );
+
+
+ if( i_y_len > 128 || i_read+2+i_y_len > i_packet_len )
+ return VLC_EGENERIC;
+
+ memcpy( p_key->y, p_buf, 2+i_y_len );
+ i_read += 2+i_y_len;
+
+ if( i_read != i_packet_len ) /* some extra data eh ? */
+ return VLC_EGENERIC;
+
+ return VLC_SUCCESS;
+}
+
+
+static size_t parse_signature_v3_packet( signature_packet_t *p_sig,
+ uint8_t *p_buf, size_t i_sig_len )
+{
+ size_t i_read = 1; /* we already read the version byte */
+
+ if( i_sig_len < 19 ) /* signature is at least 19 bytes + the 2 MPIs */
+ return 0;
+
+ p_sig->specific.v3.hashed_data_len = *p_buf++; i_read++;
+ if( p_sig->specific.v3.hashed_data_len != 5 )
+ return 0;
+
+ p_sig->type = *p_buf++; i_read++;
+
+ memcpy( p_sig->specific.v3.timestamp, p_buf, 4 );
+ p_buf += 4; i_read += 4;
+
+ memcpy( p_sig->issuer_longid, p_buf, 8 );
+ p_buf += 8; i_read += 8;
+
+ p_sig->public_key_algo = *p_buf++; i_read++;
+
+ p_sig->digest_algo = *p_buf++; i_read++;
+
+ p_sig->hash_verification[0] = *p_buf++; i_read++;
+ p_sig->hash_verification[1] = *p_buf++; i_read++;
+
+ assert( i_read == 19 );
+
+ return i_read;
+}
+
+
+/*
+ * fill a signature_packet_v4_t from signature packet data
+ * verify that it was used with a DSA public key, using SHA-1 digest
+ */
+static size_t parse_signature_v4_packet( signature_packet_t *p_sig,
+ uint8_t *p_buf, size_t i_sig_len )
+{
+ size_t i_read = 1; /* we already read the version byte */
+
+ if( i_sig_len < 10 ) /* signature is at least 10 bytes + the 2 MPIs */
+ return 0;
+
+ p_sig->type = *p_buf++; i_read++;
+
+ p_sig->public_key_algo = *p_buf++; i_read++;
+
+ p_sig->digest_algo = *p_buf++; i_read++;
+
+ memcpy( p_sig->specific.v4.hashed_data_len, p_buf, 2 );
+ p_buf += 2; i_read += 2;
+
+ size_t i_hashed_data_len =
+ scalar_number( p_sig->specific.v4.hashed_data_len, 2 );
+ i_read += i_hashed_data_len;
+ if( i_read + 4 > i_sig_len )
+ return 0;
+
+ p_sig->specific.v4.hashed_data = (uint8_t*) malloc( i_hashed_data_len );
+ if( !p_sig->specific.v4.hashed_data )
+ return 0;
+ memcpy( p_sig->specific.v4.hashed_data, p_buf, i_hashed_data_len );
+ p_buf += i_hashed_data_len;
+
+ memcpy( p_sig->specific.v4.unhashed_data_len, p_buf, 2 );
+ p_buf += 2; i_read += 2;
+
+ size_t i_unhashed_data_len =
+ scalar_number( p_sig->specific.v4.unhashed_data_len, 2 );
+ i_read += i_unhashed_data_len;
+ if( i_read + 2 > i_sig_len )
+ return 0;
+
+ p_sig->specific.v4.unhashed_data = (uint8_t*) malloc( i_unhashed_data_len );
+ if( !p_sig->specific.v4.unhashed_data )
+ return 0;
+
+ memcpy( p_sig->specific.v4.unhashed_data, p_buf, i_unhashed_data_len );
+ p_buf += i_unhashed_data_len;
+
+ memcpy( p_sig->hash_verification, p_buf, 2 );
+ p_buf += 2; i_read += 2;
+
+ uint8_t *p, *max_pos;
+ p = p_sig->specific.v4.unhashed_data;
+ max_pos = p + scalar_number( p_sig->specific.v4.unhashed_data_len, 2 );
+
+ for( ;; )
+ {
+ if( p > max_pos )
+ return 0;
+
+ size_t i_subpacket_len;
+ if( *p < 192 )
+ {
+ if( p + 1 > max_pos )
+ return 0;
+ i_subpacket_len = *p++;
+ }
+ else if( *p < 255 )
+ {
+ if( p + 2 > max_pos )
+ return 0;
+ i_subpacket_len = (*p++ - 192) << 8;
+ i_subpacket_len += *p++ + 192;
+ }
+ else
+ {
+ if( p + 4 > max_pos )
+ return 0;
+ i_subpacket_len = *++p << 24;
+ i_subpacket_len += *++p << 16;
+ i_subpacket_len += *++p << 8;
+ i_subpacket_len += *++p;
+ }
+
+ if( *p == ISSUER_SUBPACKET )
+ {
+ if( p + 9 > max_pos )
+ return 0;
+
+ memcpy( &p_sig->issuer_longid, p+1, 8 );
+
+ return i_read;
+ }
+
+ p += i_subpacket_len;
+ }
+}
+
+
+static int parse_signature_packet( signature_packet_t *p_sig,
+ uint8_t *p_buf, size_t i_sig_len )
+{
+ if( !i_sig_len ) /* 1st sanity check, we need at least the version */
+ return VLC_EGENERIC;
+
+ p_sig->version = *p_buf++;
+
+ size_t i_read;
+ switch( p_sig->version )
+ {
+ case 3:
+ i_read = parse_signature_v3_packet( p_sig, p_buf, i_sig_len );
+ break;
+ case 4:
+ p_sig->specific.v4.hashed_data = NULL;
+ p_sig->specific.v4.unhashed_data = NULL;
+ i_read = parse_signature_v4_packet( p_sig, p_buf, i_sig_len );
+ break;
+ default:
+ return VLC_EGENERIC;
+ }
+
+ if( i_read == 0 ) /* signature packet parsing has failed */
+ goto error;
+
+ if( p_sig->public_key_algo != PUBLIC_KEY_ALGO_DSA )
+ goto error;
+
+ if( p_sig->digest_algo != DIGEST_ALGO_SHA1 )
+ goto error;
+
+ switch( p_sig->type )
+ {
+ case BINARY_SIGNATURE:
+ case TEXT_SIGNATURE:
+ case GENERIC_KEY_SIGNATURE:
+ case PERSONA_KEY_SIGNATURE:
+ case CASUAL_KEY_SIGNATURE:
+ case POSITIVE_KEY_SIGNATURE:
+ break;
+ default:
+ goto error;
+ }
+
+ p_buf--; /* rewind to the version byte */
+ p_buf += i_read;
+
+ if( i_read + 2 > i_sig_len )
+ goto error;
+
+ size_t i_r_len = mpi_len( p_buf ); i_read += 2;
+ if( i_read + i_r_len > i_sig_len || i_r_len > 20 )
+ goto error;
+
+ memcpy( p_sig->r, p_buf, 2 + i_r_len );
+ p_buf += 2 + i_r_len;
+ i_read += i_r_len;
+
+ if( i_read + 2 > i_sig_len )
+ goto error;
+
+ size_t i_s_len = mpi_len( p_buf ); i_read += 2;
+ if( i_read + i_s_len > i_sig_len || i_s_len > 20 )
+ goto error;
+
+ memcpy( p_sig->s, p_buf, 2 + i_s_len );
+ p_buf += 2 + i_s_len;
+ i_read += i_s_len;
+
+ assert( i_read == i_sig_len );
+ if( i_read < i_sig_len ) /* some extra data, hm ? */
+ goto error;
+
+ return VLC_SUCCESS;
+
+error:
+
+ if( p_sig->version == 4 )
+ {
+ free( p_sig->specific.v4.hashed_data );
+ free( p_sig->specific.v4.unhashed_data );
+ }
+
+ return VLC_EGENERIC;
+}
+
+
+/*
+ * crc_octets() was lamely copied from rfc 2440
+ * Copyright (C) The Internet Society (1998). All Rights Reserved.
+ */
+#define CRC24_INIT 0xB704CEL
+#define CRC24_POLY 0x1864CFBL
+
+static long crc_octets( uint8_t *octets, size_t len )
+{
+ long crc = CRC24_INIT;
+ int i;
+ while (len--)
+ {
+ crc ^= (*octets++) << 16;
+ for (i = 0; i < 8; i++)
+ {
+ crc <<= 1;
+ if (crc & 0x1000000)
+ crc ^= CRC24_POLY;
+ }
+ }
+ return crc & 0xFFFFFFL;
+}
+
+
+/*
+ * Transform an armored document in binary format
+ * Used on public keys and signatures
+ */
+static int pgp_unarmor( char *p_ibuf, size_t i_ibuf_len,
+ uint8_t *p_obuf, size_t i_obuf_len )
+{
+ char *p_ipos = p_ibuf;
+ uint8_t *p_opos = p_obuf;
+ int i_end = 0;
+ int i_header_skipped = 0;
+
+ while( !i_end && p_ipos < p_ibuf + i_ibuf_len && *p_ipos != '=' )
+ {
+ if( *p_ipos == '\r' || *p_ipos == '\n' )
+ {
+ p_ipos++;
+ continue;
+ }
+
+ size_t i_line_len = strcspn( p_ipos, "\r\n" );
+ if( i_line_len == 0 )
+ continue;
+
+ if( !i_header_skipped )
+ {
+ if( !strncmp( p_ipos, "-----BEGIN PGP", 14 ) )
+ i_header_skipped = 1;
+
+ p_ipos += i_line_len + 1;
+ continue;
+ }
+
+ if( !strncmp( p_ipos, "Version:", 8 ) )
+ {
+ p_ipos += i_line_len + 1;
+ continue;
+ }
+
+ if( p_ipos[i_line_len - 1] == '=' )
+ {
+ i_end = 1;
+ p_ipos[i_line_len - 1] = '\0';
+ }
+ else
+ p_ipos[i_line_len] = '\0';
+
+ p_opos += vlc_b64_decode_binary_to_buffer( p_opos,
+ p_obuf - p_opos + i_obuf_len, p_ipos );
+ p_ipos += i_line_len + 1;
+ }
+
+ /* XXX: the CRC is OPTIONAL, really require it ? */
+ if( p_ipos + 5 > p_ibuf + i_ibuf_len || *p_ipos++ != '=' )
+ return 0;
+
+ uint8_t p_crc[3];
+ if( vlc_b64_decode_binary_to_buffer( p_crc, 3, p_ipos ) != 3 )
+ return 0;
+
+ long l_crc = crc_octets( p_obuf, p_opos - p_obuf );
+ long l_crc2 = ( 0 << 24 ) + ( p_crc[0] << 16 ) + ( p_crc[1] << 8 ) + p_crc[2];
+
+ return l_crc2 == l_crc ? p_opos - p_obuf : 0;
+}
+
+
+/*
+ * Verify an OpenPGP signature made on some SHA-1 hash, with some DSA public key
+ */
+int verify_signature( uint8_t *p_r, uint8_t *p_s, public_key_packet_t *p_key,
+ uint8_t *p_hash )
+{
+ /* the data to be verified (a SHA-1 hash) */
+ const char *hash_sexp_s = "(data(flags raw)(value %m))";
+ /* the public key */
+ const char *key_sexp_s = "(public-key(dsa(p %m)(q %m)(g %m)(y %m)))";
+ /* the signature */
+ const char *sig_sexp_s = "(sig-val(dsa(r %m )(s %m )))";
+
+ size_t erroff;
+ gcry_mpi_t p, q, g, y, r, s, hash;
+ p = q = g = y = r = s = hash = NULL;
+ gcry_sexp_t key_sexp, hash_sexp, sig_sexp;
+ key_sexp = hash_sexp = sig_sexp = NULL;
+
+ int i_p_len = mpi_len( p_key->p );
+ int i_q_len = mpi_len( p_key->q );
+ int i_g_len = mpi_len( p_key->g );
+ int i_y_len = mpi_len( p_key->y );
+ if( gcry_mpi_scan( &p, GCRYMPI_FMT_USG, p_key->p + 2, i_p_len, NULL ) ||
+ gcry_mpi_scan( &q, GCRYMPI_FMT_USG, p_key->q + 2, i_q_len, NULL ) ||
+ gcry_mpi_scan( &g, GCRYMPI_FMT_USG, p_key->g + 2, i_g_len, NULL ) ||
+ gcry_mpi_scan( &y, GCRYMPI_FMT_USG, p_key->y + 2, i_y_len, NULL ) ||
+ gcry_sexp_build( &key_sexp, &erroff, key_sexp_s, p, q, g, y ) )
+ goto problem;
+
+ int i_r_len = mpi_len( p_r );
+ int i_s_len = mpi_len( p_s );
+ if( gcry_mpi_scan( &r, GCRYMPI_FMT_USG, p_r + 2, i_r_len, NULL ) ||
+ gcry_mpi_scan( &s, GCRYMPI_FMT_USG, p_s + 2, i_s_len, NULL ) ||
+ gcry_sexp_build( &sig_sexp, &erroff, sig_sexp_s, r, s ) )
+ goto problem;
+
+ int i_hash_len = 20;
+ if( gcry_mpi_scan( &hash, GCRYMPI_FMT_USG, p_hash, i_hash_len, NULL ) ||
+ gcry_sexp_build( &hash_sexp, &erroff, hash_sexp_s, hash ) )
+ goto problem;
+
+ if( gcry_pk_verify( sig_sexp, hash_sexp, key_sexp ) )
+ goto problem;
+
+ return VLC_SUCCESS;
+
+problem:
+ if( p ) gcry_mpi_release( p );
+ if( q ) gcry_mpi_release( q );
+ if( g ) gcry_mpi_release( g );
+ if( y ) gcry_mpi_release( y );
+ if( r ) gcry_mpi_release( r );
+ if( s ) gcry_mpi_release( s );
+ if( hash ) gcry_mpi_release( hash );
+ if( key_sexp ) gcry_sexp_release( key_sexp );
+ if( sig_sexp ) gcry_sexp_release( sig_sexp );
+ if( hash_sexp ) gcry_sexp_release( hash_sexp );
+ return VLC_EGENERIC;
+}
+
+
+/*
+ * fill a public_key_t with public key data, including:
+ * * public key packet
+ * * signature packet issued by key which long id is p_sig_issuer
+ * * user id packet
+ */
+int parse_public_key( const uint8_t *p_key_data, size_t i_key_len,
+ public_key_t *p_key, const uint8_t *p_sig_issuer )
+{
+ uint8_t *pos = (uint8_t*) p_key_data;
+ uint8_t *max_pos = pos + i_key_len;
+
+ int i_status = 0;
+#define PUBLIC_KEY_FOUND 0x01
+#define USER_ID_FOUND 0x02
+#define SIGNATURE_FOUND 0X04
+
+ uint8_t *p_key_unarmored = NULL;
+
+ p_key->psz_username = NULL;
+ p_key->sig.specific.v4.hashed_data = NULL;
+ p_key->sig.specific.v4.unhashed_data = NULL;
+
+ if( !( *pos & 0x80 ) )
+ { /* first byte is ASCII, unarmoring */
+ p_key_unarmored = (uint8_t*)malloc( i_key_len );
+ if( !p_key_unarmored )
+ return VLC_ENOMEM;
+ int i_len = pgp_unarmor( (char*)p_key_data, i_key_len,
+ p_key_unarmored, i_key_len );
+
+ if( i_len == 0 )
+ goto error;
+
+ pos = p_key_unarmored;
+ max_pos = pos + i_len;
+ }
+
+ while( pos < max_pos )
+ {
+ if( !(*pos & 0x80) || *pos & 0x40 )
+ goto error;
+
+ int i_type = packet_type( *pos );
+
+ int i_header_len = packet_header_len( *pos++ );
+ if( pos + i_header_len > max_pos ||
+ ( i_header_len != 1 && i_header_len != 2 && i_header_len != 4 ) )
+ goto error;
+
+ int i_packet_len = scalar_number( pos, i_header_len );
+ pos += i_header_len;
+
+ if( pos + i_packet_len > max_pos )
+ goto error;
+
+ switch( i_type )
+ {
+ case PUBLIC_KEY_PACKET:
+ i_status |= PUBLIC_KEY_FOUND;
+ if( parse_public_key_packet( &p_key->key, pos, i_packet_len ) != VLC_SUCCESS )
+ goto error;
+ break;
+
+ case SIGNATURE_PACKET: /* we accept only v4 signatures here */
+ if( i_status & SIGNATURE_FOUND || !p_sig_issuer )
+ break;
+ int i_ret = parse_signature_packet( &p_key->sig, pos,
+ i_packet_len );
+ if( i_ret == VLC_SUCCESS )
+ {
+ if( p_key->sig.version != 4 )
+ break;
+ if( memcmp( p_key->sig.issuer_longid, p_sig_issuer, 8 ) )
+ {
+ free( p_key->sig.specific.v4.hashed_data );
+ free( p_key->sig.specific.v4.unhashed_data );
+ p_key->sig.specific.v4.hashed_data = NULL;
+ p_key->sig.specific.v4.unhashed_data = NULL;
+ break;
+ }
+ i_status |= SIGNATURE_FOUND;
+ }
+ break;
+
+ case USER_ID_PACKET:
+ if( p_key->psz_username ) /* save only the first User ID */
+ break;
+ i_status |= USER_ID_FOUND;
+ p_key->psz_username = (uint8_t*)malloc( i_packet_len + 1);
+ if( !p_key->psz_username )
+ goto error;
+
+ memcpy( p_key->psz_username, pos, i_packet_len );
+ p_key->psz_username[i_packet_len] = '\0';
+ break;
+
+ default:
+ break;
+ }
+ pos += i_packet_len;
+ }
+ free( p_key_unarmored );
+
+ if( !( i_status & ( PUBLIC_KEY_FOUND | USER_ID_FOUND ) ) )
+ return VLC_EGENERIC;
+
+ if( p_sig_issuer && !( i_status & SIGNATURE_FOUND ) )
+ return VLC_EGENERIC;
+
+ return VLC_SUCCESS;
+
+error:
+ if( p_key->sig.version == 4 )
+ {
+ free( p_key->sig.specific.v4.hashed_data );
+ free( p_key->sig.specific.v4.unhashed_data );
+ }
+ free( p_key->psz_username );
+ free( p_key_unarmored );
+ return VLC_EGENERIC;
+}
+
+
+/* hash a text
+ * * provided as a buffer (\0 terminated)
+ * * with "\r\n" line endings if it's a text signature, else use UNIX line
+ * * endings
+ */
+static int hash_from_string( const char *psz_string, gcry_md_hd_t hd,
+ bool text_signature )
+{
+ while( *psz_string )
+ {
+ size_t i_len = strcspn( psz_string, "\r\n" );
+ if( !i_len )
+ break;
+
+ gcry_md_write( hd, psz_string, i_len );
+ if( text_signature )
+ gcry_md_putc( hd, '\r' );
+ gcry_md_putc( hd, '\n' );
+
+ psz_string += i_len;
+ while( *psz_string == '\r' || *psz_string == '\n' )
+ psz_string++;
+ }
+
+ return 0;
+}
+
+
+/* hash a binary file */
+static int hash_from_binary_file( const char *psz_file, gcry_md_hd_t hd )
+{
+ uint8_t buffer[4096];
+ size_t i_read;
+
+ FILE *f = utf8_fopen( psz_file, "r" );
+ if( !f )
+ return -1;
+
+ while( ( i_read = fread( buffer, 1, sizeof(buffer), f ) ) > 0 )
+ gcry_md_write( hd, buffer, i_read );
+
+ fclose( f );
+
+ return 0;
+}
+
+
+/* final part of the hash */
+static uint8_t *hash_finish( gcry_md_hd_t hd, signature_packet_t *p_sig )
+{
+ if( p_sig->version == 3 )
+ {
+ gcry_md_putc( hd, p_sig->type );
+ gcry_md_write( hd, &p_sig->specific.v3.timestamp, 4 );
+ }
+ else if( p_sig->version == 4 )
+ {
+ gcry_md_putc( hd, p_sig->version );
+ gcry_md_putc( hd, p_sig->type );
+ gcry_md_putc( hd, p_sig->public_key_algo );
+ gcry_md_putc( hd, p_sig->digest_algo );
+ gcry_md_write( hd, p_sig->specific.v4.hashed_data_len, 2 );
+ size_t i_len = scalar_number( p_sig->specific.v4.hashed_data_len, 2 );
+ gcry_md_write( hd, p_sig->specific.v4.hashed_data, i_len );
+
+ gcry_md_putc( hd, 0x04 );
+ gcry_md_putc( hd, 0xFF );
+
+ i_len += 6; /* hashed data + 6 bytes header */
+
+ gcry_md_putc( hd, (i_len >> 24) & 0xff );
+ gcry_md_putc( hd, (i_len >> 16) & 0xff );
+ gcry_md_putc( hd, (i_len >> 8) & 0xff );
+ gcry_md_putc( hd, (i_len) & 0xff );
+ }
+ else
+ { /* RFC 4880 only tells about versions 3 and 4 */
+ return NULL;
+ }
+
+ gcry_md_final( hd );
+
+ uint8_t *p_tmp = (uint8_t*) gcry_md_read( hd, GCRY_MD_SHA1);
+ uint8_t *p_hash = malloc( 20 );
+ if( p_hash )
+ memcpy( p_hash, p_tmp, 20 );
+ gcry_md_close( hd );
+ return p_hash;
+}
+
+
+/*
+ * return a sha1 hash of a text
+ */
+uint8_t *hash_sha1_from_text( const char *psz_string,
+ signature_packet_t *p_sig )
+{
+ gcry_md_hd_t hd;
+ if( gcry_md_open( &hd, GCRY_MD_SHA1, 0 ) )
+ return NULL;
+
+ if( hash_from_string( psz_string, hd, p_sig->type == TEXT_SIGNATURE ) < 0 )
+ {
+ gcry_md_close( hd );
+ return NULL;
+ }
+
+ return hash_finish( hd, p_sig );
+}
+
+
+/*
+ * return a sha1 hash of a file
+ */
+uint8_t *hash_sha1_from_file( const char *psz_file, signature_packet_t *p_sig )
+{
+ gcry_md_hd_t hd;
+ if( gcry_md_open( &hd, GCRY_MD_SHA1, 0 ) )
+ return NULL;
+
+ if( hash_from_binary_file( psz_file, hd ) < 0 )
+ {
+ gcry_md_close( hd );
+ return NULL;
+ }
+
+ return hash_finish( hd, p_sig );
+}
+
+
+/*
+ * Generate a SHA1 hash on a public key, to verify a signature made on that hash
+ * Note that we need the signature (v4) to compute the hash
+ */
+uint8_t *hash_sha1_from_public_key( public_key_t *p_pkey )
+{
+ if( p_pkey->sig.version != 4 )
+ return NULL;
+
+ if( p_pkey->sig.type < GENERIC_KEY_SIGNATURE ||
+ p_pkey->sig.type > POSITIVE_KEY_SIGNATURE )
+ return NULL;
+
+ gcry_error_t error = 0;
+ gcry_md_hd_t hd;
+
+ error = gcry_md_open( &hd, GCRY_MD_SHA1, 0 );
+ if( error )
+ return NULL;
+
+ gcry_md_putc( hd, 0x99 );
+
+ size_t i_p_len = mpi_len( p_pkey->key.p );
+ size_t i_g_len = mpi_len( p_pkey->key.g );
+ size_t i_q_len = mpi_len( p_pkey->key.q );
+ size_t i_y_len = mpi_len( p_pkey->key.y );
+
+ size_t i_size = 6 + 2*4 + i_p_len + i_g_len + i_q_len + i_y_len;
+
+ gcry_md_putc( hd, (i_size >> 8) & 0xff );
+ gcry_md_putc( hd, i_size & 0xff );
+
+ gcry_md_putc( hd, p_pkey->key.version );
+ gcry_md_write( hd, p_pkey->key.timestamp, 4 );
+ gcry_md_putc( hd, p_pkey->key.algo );
+
+ gcry_md_write( hd, (uint8_t*)&p_pkey->key.p, 2 );
+ gcry_md_write( hd, (uint8_t*)&p_pkey->key.p + 2, i_p_len );
+
+ gcry_md_write( hd, (uint8_t*)&p_pkey->key.q, 2 );
+ gcry_md_write( hd, (uint8_t*)&p_pkey->key.q + 2, i_q_len );
+
+ gcry_md_write( hd, (uint8_t*)&p_pkey->key.g, 2 );
+ gcry_md_write( hd, (uint8_t*)&p_pkey->key.g + 2, i_g_len );
+
+ gcry_md_write( hd, (uint8_t*)&p_pkey->key.y, 2 );
+ gcry_md_write( hd, (uint8_t*)&p_pkey->key.y + 2, i_y_len );
+
+ gcry_md_putc( hd, 0xb4 );
+
+ size_t i_len = strlen((char*)p_pkey->psz_username);
+
+ gcry_md_putc( hd, (i_len >> 24) & 0xff );
+ gcry_md_putc( hd, (i_len >> 16) & 0xff );
+ gcry_md_putc( hd, (i_len >> 8) & 0xff );
+ gcry_md_putc( hd, (i_len) & 0xff );
+
+ gcry_md_write( hd, p_pkey->psz_username, i_len );
+
+ uint8_t *p_hash = hash_finish( hd, &p_pkey->sig );
+ if( !p_hash ||
+ p_hash[0] != p_pkey->sig.hash_verification[0] ||
+ p_hash[1] != p_pkey->sig.hash_verification[1] )
+ {
+ return NULL;
+ }
+
+ return p_hash;
+}
+
+
+/*
+ * download a public key (the last one) from videolan server, and parse it
+ */
+public_key_t *download_key( vlc_object_t *p_this,
+ const uint8_t *p_longid, const uint8_t *p_signature_issuer )
+{
+ char *psz_url;
+ if( asprintf( &psz_url, "http://download.videolan.org/pub/keys/%.2X%.2X%.2X%.2X%.2X%.2X%.2X%.2X.asc",
+ p_longid[0], p_longid[1], p_longid[2], p_longid[3],
+ p_longid[4], p_longid[5], p_longid[6], p_longid[7] ) == -1 )
+ return NULL;
+
+ stream_t *p_stream = stream_UrlNew( p_this, psz_url );
+ free( psz_url );
+ if( !p_stream )
+ return NULL;
+
+ int64_t i_size = stream_Size( p_stream );
+ if( i_size < 0 )
+ {
+ stream_Delete( p_stream );
+ return NULL;
+ }
+
+ uint8_t *p_buf = (uint8_t*)malloc( i_size );
+ if( !p_buf )
+ {
+ stream_Delete( p_stream );
+ return NULL;
+ }
+
+ int i_read = stream_Read( p_stream, p_buf, (int)i_size );
+ stream_Delete( p_stream );
+
+ if( i_read != (int)i_size )
+ {
+ msg_Dbg( p_this, "Couldn't read full GPG key" );
+ free( p_buf );
+ return NULL;
+ }
+
+ public_key_t *p_pkey = (public_key_t*) malloc( sizeof( public_key_t ) );
+ if( !p_pkey )
+ {
+ free( p_buf );
+ return NULL;
+ }
+
+ memcpy( p_pkey->longid, p_longid, 8 );
+
+ int i_error = parse_public_key( p_buf, i_read, p_pkey, p_signature_issuer );
+ free( p_buf );
+
+ if( i_error != VLC_SUCCESS )
+ {
+ msg_Dbg( p_this, "Couldn't parse GPG key" );
+ free( p_pkey );
+ return NULL;
+ }
+
+ return p_pkey;
+}
+
+
+/*
+ * Download the signature associated to a document or a binary file.
+ * We're given the file's url, we just append ".asc" to it and download
+ */
+int download_signature( vlc_object_t *p_this, signature_packet_t *p_sig,
+ const char *psz_url )
+{
+ char *psz_sig = (char*) malloc( strlen( psz_url ) + 4 + 1 ); /* ".asc" + \0 */
+ if( !psz_sig )
+ return VLC_ENOMEM;
+
+ strcpy( psz_sig, psz_url );
+ strcat( psz_sig, ".asc" );
+
+ stream_t *p_stream = stream_UrlNew( p_this, psz_sig );
+ free( psz_sig );
+
+ if( !p_stream )
+ return VLC_ENOMEM;
+
+ int64_t i_size = stream_Size( p_stream );
+
+ msg_Dbg( p_this, "Downloading signature (%"PRId64" bytes)", i_size );
+ uint8_t *p_buf = (uint8_t*)malloc( i_size );
+ if( !p_buf )
+ {
+ stream_Delete( p_stream );
+ return VLC_ENOMEM;
+ }
+
+ int i_read = stream_Read( p_stream, p_buf, (int)i_size );
+
+ stream_Delete( p_stream );
+
+ if( i_read != (int)i_size )
+ {
+ msg_Dbg( p_this,
+ "Couldn't download full signature (only %d bytes)", i_read );
+ free( p_buf );
+ return VLC_EGENERIC;
+ }
+
+ if( (uint8_t)*p_buf < 0x80 ) /* ASCII */
+ {
+ msg_Dbg( p_this, "Unarmoring signature" );
+
+ uint8_t* p_unarmored = (uint8_t*) malloc( ( i_size * 3 ) / 4 + 1 );
+ if( !p_unarmored )
+ {
+ free( p_buf );
+ return VLC_EGENERIC;
+ }
+
+ int i_bytes = pgp_unarmor( (char*)p_buf, i_size, p_unarmored, i_size );
+ free( p_buf );
+
+ p_buf = p_unarmored;
+ i_size = i_bytes;
+
+ if( i_bytes < 2 )
+ {
+ free( p_buf );
+ msg_Dbg( p_this, "Unarmoring failed : corrupted signature ?" );
+ return VLC_EGENERIC;
+ }
+ }
+
+ if( packet_type( *p_buf ) != SIGNATURE_PACKET )
+ {
+ free( p_buf );
+ msg_Dbg( p_this, "Not a signature: %d", *p_buf );
+ return VLC_EGENERIC;
+ }
+
+ size_t i_header_len = packet_header_len( *p_buf );
+ if( ( i_header_len != 1 && i_header_len != 2 && i_header_len != 4 ) ||
+ i_header_len + 1 > (size_t)i_size )
+ {
+ free( p_buf );
+ msg_Dbg( p_this, "Invalid signature packet header" );
+ return VLC_EGENERIC;
+ }
+
+ size_t i_len = scalar_number( p_buf+1, i_header_len );
+ if( i_len + i_header_len + 1 != (size_t)i_size )
+ {
+ free( p_buf );
+ msg_Dbg( p_this, "Invalid signature packet" );
+ return VLC_EGENERIC;
+ }
+
+ int i_ret = parse_signature_packet( p_sig, p_buf+1+i_header_len, i_len );
+ free( p_buf );
+ if( i_ret != VLC_SUCCESS )
+ {
+ msg_Dbg( p_this, "Couldn't parse signature" );
+ return i_ret;
+ }
+
+ if( p_sig->type != BINARY_SIGNATURE && p_sig->type != TEXT_SIGNATURE )
+ {
+ msg_Dbg( p_this, "Invalid signature type: %d", p_sig->type );
+ if( p_sig->version == 4 )
+ {
+ free( p_sig->specific.v4.hashed_data );
+ free( p_sig->specific.v4.unhashed_data );
+ }
+ return VLC_EGENERIC;
+ }
+
+ return VLC_SUCCESS;
+}
projects / vlc / commitdiff