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 <stdatomic.h>
  24
  25 #include <vlc_update.h>
  26
  27 enum    /* Packet types */
  28 {
  29     SIGNATURE_PACKET    = 0x02,
  30     PUBLIC_KEY_PACKET   = 0x06,
  31     USER_ID_PACKET      = 0x0d
  32 };
  33
  34 enum    /* Signature types */
  35 {
  36     BINARY_SIGNATURE        = 0x00,
  37     TEXT_SIGNATURE          = 0x01,
  38
  39     /* Public keys signatures */
  40     GENERIC_KEY_SIGNATURE   = 0x10, /* No assumption of verification */
  41     PERSONA_KEY_SIGNATURE   = 0x11, /* No verification has been made */
  42     CASUAL_KEY_SIGNATURE    = 0x12, /* Some casual verification */
  43     POSITIVE_KEY_SIGNATURE  = 0x13  /* Substantial verification */
  44 };
  45
  46 enum    /* Signature subpacket types */
  47 {
  48     ISSUER_SUBPACKET    = 0x10
  49 };
  50
  51 struct public_key_packet_t
  52 {
  53
  54     uint8_t version;      /* we use only version 4 */
  55     uint8_t timestamp[4]; /* creation time of the key */
  56     uint8_t algo;         /* DSA or RSA */
  57
  58     /* the multi precision integers, with their 2 bytes length header */
  59     union {
  60         struct {
  61             uint8_t p[2+3072/8];
  62             uint8_t q[2+256/8];
  63             uint8_t g[2+3072/8];
  64             uint8_t y[2+3072/8];
  65         } dsa ;
  66         struct {
  67             uint8_t n[2+4096/8];
  68             uint8_t e[2+4096/8];
  69         } rsa;
  70     } sig;
  71 };
  72
  73 /* used for public key and file signatures */
  74 struct signature_packet_t
  75 {
  76     uint8_t version; /* 3 or 4 */
  77
  78     uint8_t type;
  79     uint8_t public_key_algo;    /* DSA or RSA */
  80     uint8_t digest_algo;
  81
  82     uint8_t hash_verification[2];
  83     uint8_t issuer_longid[8];
  84
  85     union   /* version specific data */
  86     {
  87         struct
  88         {
  89             uint8_t hashed_data_len[2];     /* scalar number */
  90             uint8_t *hashed_data;           /* hashed_data_len bytes */
  91             uint8_t unhashed_data_len[2];   /* scalar number */
  92             uint8_t *unhashed_data;         /* unhashed_data_len bytes */
  93         } v4;
  94         struct
  95         {
  96             uint8_t hashed_data_len;    /* MUST be 5 */
  97             uint8_t timestamp[4];       /* 4 bytes scalar number */
  98         } v3;
  99     } specific;
 100
 101 /* The part below is made of consecutive MPIs, their number and size being
 102  * public-key-algorithm dependent.
 103  */
 104     union {
 105         struct {
 106             uint8_t r[2+256/8];
 107             uint8_t s[2+256/8];
 108         } dsa;
 109         struct {
 110             uint8_t s[2+4096/8];
 111         } rsa;
 112     } algo_specific;
 113 };
 114
 115 typedef struct public_key_packet_t public_key_packet_t;
 116 typedef struct signature_packet_t signature_packet_t;
 117
 118 struct public_key_t
 119 {
 120     uint8_t longid[8];       /* Long id */
 121     uint8_t *psz_username;    /* USER ID */
 122
 123     public_key_packet_t key;       /* Public key packet */
 124
 125     signature_packet_t sig;     /* Signature packet, by the embedded key */
 126 };
 127
 128 typedef struct public_key_t public_key_t;
 129
 130 /**
 131  * Non blocking binary download
 132  */
 133 typedef struct
 134 {
 135     struct vlc_common_members obj;
 136
 137     vlc_thread_t thread;
 138     atomic_bool aborted;
 139     update_t *p_update;
 140     char *psz_destdir;
 141 } update_download_thread_t;
 142
 143 /**
 144  * Non blocking update availability verification
 145  */
 146 typedef struct
 147 {
 148     vlc_thread_t thread;
 149
 150     update_t *p_update;
 151     void (*pf_callback)( void *, bool );
 152     void *p_data;
 153 } update_check_thread_t;
 154
 155 /**
 156  * The update object. Stores (and caches) all information relative to updates
 157  */
 158 struct update_t
 159 {
 160     libvlc_int_t *p_libvlc;
 161     vlc_mutex_t lock;
 162     struct update_release_t release;    ///< Release (version)
 163     public_key_t *p_pkey;
 164     update_download_thread_t *p_download;
 165     update_check_thread_t *p_check;
 166 };
 167
 168 /*
 169  * download a public key (the last one) from videolan server, and parse it
 170  */
 171 public_key_t *
 172 download_key(
 173         vlc_object_t *p_this, const uint8_t *p_longid,
 174         const uint8_t *p_signature_issuer );
 175
 176 /*
 177  * fill a public_key_t with public key data, including:
 178  *   * public key packet
 179  *   * signature packet issued by key which long id is p_sig_issuer
 180  *   * user id packet
 181  */
 182 int
 183 parse_public_key(
 184         const uint8_t *p_key_data, size_t i_key_len, public_key_t *p_key,
 185         const uint8_t *p_sig_issuer );
 186
 187 /*
 188  * Verify an OpenPGP signature made on some hash, with some public key
 189  */
 190 int
 191 verify_signature(signature_packet_t *sign, public_key_packet_t *p_key,
 192         uint8_t *p_hash );
 193
 194 /*
 195  * Download the signature associated to a document or a binary file.
 196  * We're given the file's url, we just append ".asc" to it and download
 197  */
 198 int
 199 download_signature(
 200         vlc_object_t *p_this, signature_packet_t *p_sig, const char *psz_url );
 201
 202 /*
 203  * return a hash of a text
 204  */
 205 uint8_t *
 206 hash_from_text(
 207         const char *psz_text, signature_packet_t *p_sig );
 208
 209 /*
 210  * return a hash of a file
 211  */
 212 uint8_t *
 213 hash_from_file(
 214         const char *psz_file, signature_packet_t *p_sig );
 215
 216 /*
 217  * return a hash of a public key
 218  */
 219 uint8_t *
 220 hash_from_public_key( public_key_t *p_pkey );