t/t5303-pack-corruption-resilience.sh

   1 #!/bin/sh
   2 #
   3 # Copyright (c) 2008 Nicolas Pitre
   4 #
   5
   6 test_description='resilience to pack corruptions with redundant objects'
   7 . ./test-lib.sh
   8
   9 # Note: the test objects are created with knowledge of their pack encoding
  10 # to ensure good code path coverage, and to facilitate direct alteration
  11 # later on.  The assumed characteristics are:
  12 #
  13 # 1) blob_2 is a delta with blob_1 for base and blob_3 is a delta with blob2
  14 #    for base, such that blob_3 delta depth is 2;
  15 #
  16 # 2) the bulk of object data is uncompressible so the text part remains
  17 #    visible;
  18 #
  19 # 3) object header is always 2 bytes.
  20
  21 create_test_files() {
  22     test-genrandom "foo" 2000 > file_1 &&
  23     test-genrandom "foo" 1800 > file_2 &&
  24     test-genrandom "foo" 1800 > file_3 &&
  25     echo " base " >> file_1 &&
  26     echo " delta1 " >> file_2 &&
  27     echo " delta delta2 " >> file_3 &&
  28     test-genrandom "bar" 150 >> file_2 &&
  29     test-genrandom "baz" 100 >> file_3
  30 }
  31
  32 create_new_pack() {
  33     rm -rf .git &&
  34     git init &&
  35     blob_1=`git hash-object -t blob -w file_1` &&
  36     blob_2=`git hash-object -t blob -w file_2` &&
  37     blob_3=`git hash-object -t blob -w file_3` &&
  38     pack=`printf "$blob_1\n$blob_2\n$blob_3\n" |
  39           git pack-objects $@ .git/objects/pack/pack` &&
  40     pack=".git/objects/pack/pack-${pack}" &&
  41     git verify-pack -v ${pack}.pack
  42 }
  43
  44 zeros () {
  45         while :; do
  46                 echo -n xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
  47         done | tr x '\0'
  48 }
  49
  50 do_corrupt_object() {
  51     ofs=`git show-index < ${pack}.idx | grep $1 | cut -f1 -d" "` &&
  52     ofs=$(($ofs + $2)) &&
  53     chmod +w ${pack}.pack &&
  54     zeros | dd of=${pack}.pack count=1 bs=1 conv=notrunc seek=$ofs &&
  55     test_must_fail git verify-pack ${pack}.pack
  56 }
  57
  58 test_expect_success \
  59     'initial setup validation' \
  60     'create_test_files &&
  61      create_new_pack &&
  62      git prune-packed &&
  63      git cat-file blob $blob_1 > /dev/null &&
  64      git cat-file blob $blob_2 > /dev/null &&
  65      git cat-file blob $blob_3 > /dev/null'
  66
  67 test_expect_success \
  68     'create corruption in header of first object' \
  69     'do_corrupt_object $blob_1 0 &&
  70      test_must_fail git cat-file blob $blob_1 > /dev/null &&
  71      test_must_fail git cat-file blob $blob_2 > /dev/null &&
  72      test_must_fail git cat-file blob $blob_3 > /dev/null'
  73
  74 test_expect_success \
  75     '... but having a loose copy allows for full recovery' \
  76     'mv ${pack}.idx tmp &&
  77      git hash-object -t blob -w file_1 &&
  78      mv tmp ${pack}.idx &&
  79      git cat-file blob $blob_1 > /dev/null &&
  80      git cat-file blob $blob_2 > /dev/null &&
  81      git cat-file blob $blob_3 > /dev/null'
  82
  83 test_expect_success \
  84     '... and loose copy of first delta allows for partial recovery' \
  85     'git prune-packed &&
  86      test_must_fail git cat-file blob $blob_2 > /dev/null &&
  87      mv ${pack}.idx tmp &&
  88      git hash-object -t blob -w file_2 &&
  89      mv tmp ${pack}.idx &&
  90      test_must_fail git cat-file blob $blob_1 > /dev/null &&
  91      git cat-file blob $blob_2 > /dev/null &&
  92      git cat-file blob $blob_3 > /dev/null'
  93
  94 test_expect_success \
  95     'create corruption in data of first object' \
  96     'create_new_pack &&
  97      git prune-packed &&
  98      chmod +w ${pack}.pack &&
  99      perl -i.bak -pe "s/ base /abcdef/" ${pack}.pack &&
 100      test_must_fail git cat-file blob $blob_1 > /dev/null &&
 101      test_must_fail git cat-file blob $blob_2 > /dev/null &&
 102      test_must_fail git cat-file blob $blob_3 > /dev/null'
 103
 104 test_expect_success \
 105     '... but having a loose copy allows for full recovery' \
 106     'mv ${pack}.idx tmp &&
 107      git hash-object -t blob -w file_1 &&
 108      mv tmp ${pack}.idx &&
 109      git cat-file blob $blob_1 > /dev/null &&
 110      git cat-file blob $blob_2 > /dev/null &&
 111      git cat-file blob $blob_3 > /dev/null'
 112
 113 test_expect_success \
 114     '... and loose copy of second object allows for partial recovery' \
 115     'git prune-packed &&
 116      test_must_fail git cat-file blob $blob_2 > /dev/null &&
 117      mv ${pack}.idx tmp &&
 118      git hash-object -t blob -w file_2 &&
 119      mv tmp ${pack}.idx &&
 120      test_must_fail git cat-file blob $blob_1 > /dev/null &&
 121      git cat-file blob $blob_2 > /dev/null &&
 122      git cat-file blob $blob_3 > /dev/null'
 123
 124 test_expect_success \
 125     'create corruption in header of first delta' \
 126     'create_new_pack &&
 127      git prune-packed &&
 128      do_corrupt_object $blob_2 0 &&
 129      git cat-file blob $blob_1 > /dev/null &&
 130      test_must_fail git cat-file blob $blob_2 > /dev/null &&
 131      test_must_fail git cat-file blob $blob_3 > /dev/null'
 132
 133 test_expect_success \
 134     '... but having a loose copy allows for full recovery' \
 135     'mv ${pack}.idx tmp &&
 136      git hash-object -t blob -w file_2 &&
 137      mv tmp ${pack}.idx &&
 138      git cat-file blob $blob_1 > /dev/null &&
 139      git cat-file blob $blob_2 > /dev/null &&
 140      git cat-file blob $blob_3 > /dev/null'
 141
 142 test_expect_success \
 143     'create corruption in data of first delta' \
 144     'create_new_pack &&
 145      git prune-packed &&
 146      chmod +w ${pack}.pack &&
 147      perl -i.bak -pe "s/ delta1 /abcdefgh/" ${pack}.pack &&
 148      git cat-file blob $blob_1 > /dev/null &&
 149      test_must_fail git cat-file blob $blob_2 > /dev/null &&
 150      test_must_fail git cat-file blob $blob_3 > /dev/null'
 151
 152 test_expect_success \
 153     '... but having a loose copy allows for full recovery' \
 154     'mv ${pack}.idx tmp &&
 155      git hash-object -t blob -w file_2 &&
 156      mv tmp ${pack}.idx &&
 157      git cat-file blob $blob_1 > /dev/null &&
 158      git cat-file blob $blob_2 > /dev/null &&
 159      git cat-file blob $blob_3 > /dev/null'
 160
 161 test_expect_success \
 162     'corruption in delta base reference of first delta (OBJ_REF_DELTA)' \
 163     'create_new_pack &&
 164      git prune-packed &&
 165      do_corrupt_object $blob_2 2 &&
 166      git cat-file blob $blob_1 > /dev/null &&
 167      test_must_fail git cat-file blob $blob_2 > /dev/null &&
 168      test_must_fail git cat-file blob $blob_3 > /dev/null'
 169
 170 test_expect_success \
 171     '... but having a loose copy allows for full recovery' \
 172     'mv ${pack}.idx tmp &&
 173      git hash-object -t blob -w file_2 &&
 174      mv tmp ${pack}.idx &&
 175      git cat-file blob $blob_1 > /dev/null &&
 176      git cat-file blob $blob_2 > /dev/null &&
 177      git cat-file blob $blob_3 > /dev/null'
 178
 179 test_expect_success \
 180     'corruption in delta base reference of first delta (OBJ_OFS_DELTA)' \
 181     'create_new_pack --delta-base-offset &&
 182      git prune-packed &&
 183      do_corrupt_object $blob_2 2 &&
 184      git cat-file blob $blob_1 > /dev/null &&
 185      test_must_fail git cat-file blob $blob_2 > /dev/null &&
 186      test_must_fail git cat-file blob $blob_3 > /dev/null'
 187
 188 test_expect_success \
 189     '... and a redundant pack allows for full recovery too' \
 190     'mv ${pack}.idx tmp &&
 191      git hash-object -t blob -w file_1 &&
 192      git hash-object -t blob -w file_2 &&
 193      printf "$blob_1\n$blob_2\n" | git pack-objects .git/objects/pack/pack &&
 194      git prune-packed &&
 195      mv tmp ${pack}.idx &&
 196      git cat-file blob $blob_1 > /dev/null &&
 197      git cat-file blob $blob_2 > /dev/null &&
 198      git cat-file blob $blob_3 > /dev/null'
 199
 200 test_done