xattrs.diff

   1 This patch adds backward-compatibility support for the --xattrs option.
   2 Since the main release has never had xattr support, the trunk doesn't
   3 need this code.  If you want to make rsync 3.0.x communicate with an
   4 older (patched) release, use this.
   5
   6 To use this patch, run these commands for a successful build:
   7
   8     patch -p1 <patches/acls.diff
   9     patch -p1 <patches/xattrs.diff
  10     ./configure                         (optional if already run)
  11     make
  12
  13 --- old/compat.c
  14 +++ new/compat.c
  15 @@ -144,16 +144,6 @@ void setup_protocol(int f_out,int f_in)
  16                 exit_cleanup(RERR_PROTOCOL);
  17         }
  18
  19 -       if (protocol_version < 30) {
  20 -               if (preserve_xattrs && !local_server) {
  21 -                       rprintf(FERROR,
  22 -                           "--xattrs requires protocol 30 or higher"
  23 -                           " (negotiated %d).\n",
  24 -                           protocol_version);
  25 -                       exit_cleanup(RERR_PROTOCOL);
  26 -               }
  27 -       }
  28 -
  29         if (delete_mode && !(delete_before+delete_during+delete_after)) {
  30                 if (protocol_version < 30)
  31                         delete_before = 1;
  32 --- old/xattrs.c
  33 +++ new/xattrs.c
  34 @@ -20,6 +20,7 @@
  35   */
  36
  37  #include "rsync.h"
  38 +#include "io.h"
  39  #include "lib/sysxattrs.h"
  40
  41  #ifdef SUPPORT_XATTRS
  42 @@ -32,6 +33,7 @@ extern int read_only;
  43  extern int list_only;
  44  extern int preserve_xattrs;
  45  extern int checksum_seed;
  46 +extern int protocol_version;
  47
  48  #define RSYNC_XAL_INITIAL 5
  49  #define RSYNC_XAL_LIST_INITIAL 100
  50 @@ -232,7 +234,7 @@ static int rsync_xal_get(const char *fna
  51                 if (!(ptr = get_xattr_data(fname, name, &datum_len, 0)))
  52                         return -1;
  53
  54 -               if (datum_len > MAX_FULL_DATUM) {
  55 +               if (datum_len > MAX_FULL_DATUM && protocol_version >= 30) {
  56                         /* For large datums, we store a flag and a checksum. */
  57                         name_offset = 1 + MAX_DIGEST_LEN;
  58                         sum_init(checksum_seed);
  59 @@ -296,7 +298,7 @@ static int find_matching_xattr(item_list
  60                          || rxas1[j].datum_len != rxas2[j].datum_len
  61                          || strcmp(rxas1[j].name, rxas2[j].name))
  62                                 break;
  63 -                       if (rxas1[j].datum_len > MAX_FULL_DATUM) {
  64 +                       if (rxas1[j].datum_len > MAX_FULL_DATUM && protocol_version >= 30) {
  65                                 if (memcmp(rxas1[j].datum + 1,
  66                                            rxas2[j].datum + 1,
  67                                            MAX_DIGEST_LEN) != 0)
  68 @@ -333,34 +335,43 @@ int send_xattr(statx *sxp, int f)
  69  {
  70         int ndx = find_matching_xattr(sxp->xattr);
  71
  72 -       /* Send 0 (-1 + 1) to indicate that literal xattr data follows. */
  73 -       write_varint(f, ndx + 1);
  74 +       if (protocol_version < 30) {
  75 +               if (ndx < 0)
  76 +                       write_byte(f, 'X');
  77 +               else {
  78 +                       write_byte(f, 'x');
  79 +                       write_int(f, ndx);
  80 +               }
  81 +       } else {
  82 +               /* Send 0 (-1 + 1) to indicate that literal xattr data follows. */
  83 +               write_varint(f, ndx + 1);
  84 +       }
  85
  86         if (ndx < 0) {
  87                 rsync_xa *rxa;
  88                 int count = sxp->xattr->count;
  89 -               write_varint(f, count);
  90 +               write_varint30(f, count);
  91                 for (rxa = sxp->xattr->items; count--; rxa++) {
  92  #ifdef HAVE_LINUX_XATTRS
  93 -                       write_varint(f, rxa->name_len);
  94 -                       write_varint(f, rxa->datum_len);
  95 +                       write_varint30(f, rxa->name_len);
  96 +                       write_varint30(f, rxa->datum_len);
  97                         write_buf(f, rxa->name, rxa->name_len);
  98  #else
  99                         /* We strip the rsync prefix from disguised namespaces
 100                          * and put everything else in the user namespace. */
 101                         if (HAS_PREFIX(rxa->name, RSYNC_PREFIX)
 102                          && rxa->name[RPRE_LEN] != '%') {
 103 -                               write_varint(f, rxa->name_len - RPRE_LEN);
 104 -                               write_varint(f, rxa->datum_len);
 105 +                               write_varint30(f, rxa->name_len - RPRE_LEN);
 106 +                               write_varint30(f, rxa->datum_len);
 107                                 write_buf(f, rxa->name + RPRE_LEN, rxa->name_len - RPRE_LEN);
 108                         } else {
 109 -                               write_varint(f, rxa->name_len + UPRE_LEN);
 110 -                               write_varint(f, rxa->datum_len);
 111 +                               write_varint30(f, rxa->name_len + UPRE_LEN);
 112 +                               write_varint30(f, rxa->datum_len);
 113                                 write_buf(f, USER_PREFIX, UPRE_LEN);
 114                                 write_buf(f, rxa->name, rxa->name_len);
 115                         }
 116  #endif
 117 -                       if (rxa->datum_len > MAX_FULL_DATUM)
 118 +                       if (rxa->datum_len > MAX_FULL_DATUM && protocol_version >= 30)
 119                                 write_buf(f, rxa->datum + 1, MAX_DIGEST_LEN);
 120                         else
 121                                 write_buf(f, rxa->datum, rxa->datum_len);
 122 @@ -410,7 +421,7 @@ int xattr_diff(struct file_struct *file,
 123                 cmp = rec_cnt ? strcmp(snd_rxa->name, rec_rxa->name) : -1;
 124                 if (cmp > 0)
 125                         same = 0;
 126 -               else if (snd_rxa->datum_len > MAX_FULL_DATUM) {
 127 +               else if (snd_rxa->datum_len > MAX_FULL_DATUM && protocol_version >= 30) {
 128                         same = cmp == 0 && snd_rxa->datum_len == rec_rxa->datum_len
 129                             && memcmp(snd_rxa->datum + 1, rec_rxa->datum + 1,
 130                                       MAX_DIGEST_LEN) == 0;
 131 @@ -453,6 +464,9 @@ void send_xattr_request(const char *fnam
 132         int j, cnt, prior_req = -1;
 133         rsync_xa *rxa;
 134
 135 +       if (protocol_version < 30)
 136 +               return;
 137 +
 138         lst += F_XATTR(file);
 139         cnt = lst->count;
 140         for (rxa = lst->items, j = 0; j < cnt; rxa++, j++) {
 141 @@ -524,6 +538,9 @@ void recv_xattr_request(struct file_stru
 142         rsync_xa *rxa;
 143         int rel_pos, cnt;
 144
 145 +       if (protocol_version < 30)
 146 +               return;
 147 +
 148         if (F_XATTR(file) < 0) {
 149                 rprintf(FERROR, "recv_xattr_request: internal data error!\n");
 150                 exit_cleanup(RERR_STREAMIO);
 151 @@ -570,7 +587,22 @@ void receive_xattr(struct file_struct *f
 152  {
 153         static item_list temp_xattr = EMPTY_ITEM_LIST;
 154         int count;
 155 -       int ndx = read_varint(f);
 156 +       int ndx;
 157 +
 158 +       if (protocol_version >= 30)
 159 +               ndx = read_varint(f);
 160 +       else {
 161 +               int tag = read_byte(f);
 162 +               if (tag == 'x')
 163 +                       ndx = read_int(f) + 1;
 164 +               else if (tag == 'X')
 165 +                       ndx = 0;
 166 +               else {
 167 +                       rprintf(FERROR, "receive_xattr: unknown extended attribute"
 168 +                               " type tag (%02x) for %s\n", tag, f_name(file, NULL));
 169 +                       exit_cleanup(RERR_STREAMIO);
 170 +               }
 171 +       }
 172
 173         if (ndx < 0 || (size_t)ndx > rsync_xal_l.count) {
 174                 rprintf(FERROR, "receive_xattr: xa index %d out of"
 175 @@ -583,7 +615,7 @@ void receive_xattr(struct file_struct *f
 176                 return;
 177         }
 178
 179 -       if ((count = read_varint(f)) != 0) {
 180 +       if ((count = read_varint30(f)) != 0) {
 181                 (void)EXPAND_ITEM_LIST(&temp_xattr, rsync_xa, count);
 182                 temp_xattr.count = 0;
 183         }
 184 @@ -591,9 +623,10 @@ void receive_xattr(struct file_struct *f
 185         while (count--) {
 186                 char *ptr, *name;
 187                 rsync_xa *rxa;
 188 -               size_t name_len = read_varint(f);
 189 -               size_t datum_len = read_varint(f);
 190 -               size_t dget_len = datum_len > MAX_FULL_DATUM ? 1 + MAX_DIGEST_LEN : datum_len;
 191 +               size_t name_len = read_varint30(f);
 192 +               size_t datum_len = read_varint30(f);
 193 +               size_t dget_len = datum_len > MAX_FULL_DATUM && protocol_version >= 30
 194 +                               ? 1 + MAX_DIGEST_LEN : datum_len;
 195                 size_t extra_len = MIGHT_NEED_RPRE ? RPRE_LEN : 0;
 196                 if (dget_len + extra_len < dget_len)
 197                         out_of_memory("receive_xattr"); /* overflow */