src/misc/update.h

   1 /*****************************************************************************
   2  * update.h: VLC PGP update private API
   3  *****************************************************************************
   4  * Copyright © 2007-2008 VLC authors and VideoLAN
   5  *
   6  * Authors: Rafaël Carré <funman@videolanorg>
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU Lesser General Public License as published by
  10  * the Free Software Foundation; either release 2 of the License, or
  11  * (at your option) any later release.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16  * GNU Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public License
  19  * along with this program; if not, write to the Free Software Foundation,
  20  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  21  *****************************************************************************/
  22
  23 #include <vlc_update.h>
  24 #include <vlc_atomic.h>
  25
  26 enum    /* Packet types */
  27 {
  28     SIGNATURE_PACKET    = 0x02,
  29     PUBLIC_KEY_PACKET   = 0x06,
  30     USER_ID_PACKET      = 0x0d
  31 };
  32
  33 enum    /* Signature types */
  34 {
  35     BINARY_SIGNATURE        = 0x00,
  36     TEXT_SIGNATURE          = 0x01,
  37
  38     /* Public keys signatures */
  39     GENERIC_KEY_SIGNATURE   = 0x10, /* No assumption of verification */
  40     PERSONA_KEY_SIGNATURE   = 0x11, /* No verification has been made */
  41     CASUAL_KEY_SIGNATURE    = 0x12, /* Some casual verification */
  42     POSITIVE_KEY_SIGNATURE  = 0x13  /* Substantial verification */
  43 };
  44
  45 enum    /* Signature subpacket types */
  46 {
  47     ISSUER_SUBPACKET    = 0x10
  48 };
  49
  50 struct public_key_packet_t
  51 {
  52
  53     uint8_t version;      /* we use only version 4 */
  54     uint8_t timestamp[4]; /* creation time of the key */
  55     uint8_t algo;         /* DSA or RSA */
  56
  57     /* the multi precision integers, with their 2 bytes length header */
  58     union {
  59         struct {
  60             uint8_t p[2+3072/8];
  61             uint8_t q[2+256/8];
  62             uint8_t g[2+3072/8];
  63             uint8_t y[2+3072/8];
  64         } dsa ;
  65         struct {
  66             uint8_t n[2+4096/8];
  67             uint8_t e[2+4096/8];
  68         } rsa;
  69     } sig;
  70 };
  71
  72 /* used for public key and file signatures */
  73 struct signature_packet_t
  74 {
  75     uint8_t version; /* 3 or 4 */
  76
  77     uint8_t type;
  78     uint8_t public_key_algo;    /* DSA or RSA */
  79     uint8_t digest_algo;
  80
  81     uint8_t hash_verification[2];
  82     uint8_t issuer_longid[8];
  83
  84     union   /* version specific data */
  85     {
  86         struct
  87         {
  88             uint8_t hashed_data_len[2];     /* scalar number */
  89             uint8_t *hashed_data;           /* hashed_data_len bytes */
  90             uint8_t unhashed_data_len[2];   /* scalar number */
  91             uint8_t *unhashed_data;         /* unhashed_data_len bytes */
  92         } v4;
  93         struct
  94         {
  95             uint8_t hashed_data_len;    /* MUST be 5 */
  96             uint8_t timestamp[4];       /* 4 bytes scalar number */
  97         } v3;
  98     } specific;
  99
 100 /* The part below is made of consecutive MPIs, their number and size being
 101  * public-key-algorithm dependent.
 102  */
 103     union {
 104         struct {
 105             uint8_t r[2+256/8];
 106             uint8_t s[2+256/8];
 107         } dsa;
 108         struct {
 109             uint8_t s[2+4096/8];
 110         } rsa;
 111     } algo_specific;
 112 };
 113
 114 typedef struct public_key_packet_t public_key_packet_t;
 115 typedef struct signature_packet_t signature_packet_t;
 116
 117 struct public_key_t
 118 {
 119     uint8_t longid[8];       /* Long id */
 120     uint8_t *psz_username;    /* USER ID */
 121
 122     public_key_packet_t key;       /* Public key packet */
 123
 124     signature_packet_t sig;     /* Signature packet, by the embedded key */
 125 };
 126
 127 typedef struct public_key_t public_key_t;
 128
 129 /**
 130  * Non blocking binary download
 131  */
 132 typedef struct
 133 {
 134     VLC_COMMON_MEMBERS
 135
 136     vlc_thread_t thread;
 137     atomic_bool aborted;
 138     update_t *p_update;
 139     char *psz_destdir;
 140 } update_download_thread_t;
 141
 142 /**
 143  * Non blocking update availability verification
 144  */
 145 typedef struct
 146 {
 147     vlc_thread_t thread;
 148
 149     update_t *p_update;
 150     void (*pf_callback)( void *, bool );
 151     void *p_data;
 152 } update_check_thread_t;
 153
 154 /**
 155  * The update object. Stores (and caches) all information relative to updates
 156  */
 157 struct update_t
 158 {
 159     libvlc_int_t *p_libvlc;
 160     vlc_mutex_t lock;
 161     struct update_release_t release;    ///< Release (version)
 162     public_key_t *p_pkey;
 163     update_download_thread_t *p_download;
 164     update_check_thread_t *p_check;
 165 };
 166
 167 /*
 168  * download a public key (the last one) from videolan server, and parse it
 169  */
 170 public_key_t *
 171 download_key(
 172         vlc_object_t *p_this, const uint8_t *p_longid,
 173         const uint8_t *p_signature_issuer );
 174
 175 /*
 176  * fill a public_key_t with public key data, including:
 177  *   * public key packet
 178  *   * signature packet issued by key which long id is p_sig_issuer
 179  *   * user id packet
 180  */
 181 int
 182 parse_public_key(
 183         const uint8_t *p_key_data, size_t i_key_len, public_key_t *p_key,
 184         const uint8_t *p_sig_issuer );
 185
 186 /*
 187  * Verify an OpenPGP signature made on some hash, with some public key
 188  */
 189 int
 190 verify_signature(signature_packet_t *sign, public_key_packet_t *p_key,
 191         uint8_t *p_hash );
 192
 193 /*
 194  * Download the signature associated to a document or a binary file.
 195  * We're given the file's url, we just append ".asc" to it and download
 196  */
 197 int
 198 download_signature(
 199         vlc_object_t *p_this, signature_packet_t *p_sig, const char *psz_url );
 200
 201 /*
 202  * return a hash of a text
 203  */
 204 uint8_t *
 205 hash_from_text(
 206         const char *psz_text, signature_packet_t *p_sig );
 207
 208 /*
 209  * return a hash of a file
 210  */
 211 uint8_t *
 212 hash_from_file(
 213         const char *psz_file, signature_packet_t *p_sig );
 214
 215 /*
 216  * return a hash of a public key
 217  */
 218 uint8_t *
 219 hash_from_public_key( public_key_t *p_pkey );