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Commit | Line | Data |
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171bdaca JK |
1 | # Support routines for hand-crafting weird or malicious packs. |
2 | # | |
3 | # You can make a complete pack like: | |
4 | # | |
5 | # pack_header 2 >foo.pack && | |
6 | # pack_obj e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 >>foo.pack && | |
7 | # pack_obj e68fe8129b546b101aee9510c5328e7f21ca1d18 >>foo.pack && | |
8 | # pack_trailer foo.pack | |
9 | ||
10 | # Print the big-endian 4-byte octal representation of $1 | |
11 | uint32_octal () { | |
12 | n=$1 | |
fbc812a6 KK |
13 | printf '\\%o' $(($n / 16777216)); n=$((n % 16777216)) |
14 | printf '\\%o' $(($n / 65536)); n=$((n % 65536)) | |
15 | printf '\\%o' $(($n / 256)); n=$((n % 256)) | |
16 | printf '\\%o' $(($n )); | |
171bdaca JK |
17 | } |
18 | ||
19 | # Print the big-endian 4-byte binary representation of $1 | |
20 | uint32_binary () { | |
21 | printf "$(uint32_octal "$1")" | |
22 | } | |
23 | ||
24 | # Print a pack header, version 2, for a pack with $1 objects | |
25 | pack_header () { | |
26 | printf 'PACK' && | |
27 | printf '\0\0\0\2' && | |
28 | uint32_binary "$1" | |
29 | } | |
30 | ||
31 | # Print the pack data for object $1, as a delta against object $2 (or as a full | |
32 | # object if $2 is missing or empty). The output is suitable for including | |
33 | # directly in the packfile, and represents the entirety of the object entry. | |
34 | # Doing this on the fly (especially picking your deltas) is quite tricky, so we | |
35 | # have hardcoded some well-known objects. See the case statements below for the | |
36 | # complete list. | |
37 | pack_obj () { | |
38 | case "$1" in | |
39 | # empty blob | |
db12505c | 40 | $EMPTY_BLOB) |
171bdaca JK |
41 | case "$2" in |
42 | '') | |
43 | printf '\060\170\234\003\0\0\0\0\1' | |
44 | return | |
45 | ;; | |
46 | esac | |
47 | ;; | |
48 | ||
49 | # blob containing "\7\76" | |
db12505c | 50 | $(test_oid packlib_7_76)) |
171bdaca JK |
51 | case "$2" in |
52 | '') | |
53 | printf '\062\170\234\143\267\3\0\0\116\0\106' | |
54 | return | |
55 | ;; | |
3b910d0c JK |
56 | 01d7713666f4de822776c7622c10f1b07de280dc) |
57 | printf '\165\1\327\161\66\146\364\336\202\47\166' && | |
58 | printf '\307\142\54\20\361\260\175\342\200\334\170' && | |
59 | printf '\234\143\142\142\142\267\003\0\0\151\0\114' | |
60 | return | |
61 | ;; | |
db12505c | 62 | 37c8e2c15bb22b912e59b43fd51a4f7e9465ed0b5084c5a1411d991cbe630683) |
63 | printf '\165\67\310\342\301\133\262\53\221\56\131' && | |
64 | printf '\264\77\325\32\117\176\224\145\355\13\120' && | |
65 | printf '\204\305\241\101\35\231\34\276\143\6\203\170' && | |
66 | printf '\234\143\142\142\142\267\003\0\0\151\0\114' | |
67 | return | |
68 | ;; | |
3b910d0c JK |
69 | esac |
70 | ;; | |
71 | ||
72 | # blob containing "\7\0" | |
db12505c | 73 | $(test_oid packlib_7_0)) |
3b910d0c JK |
74 | case "$2" in |
75 | '') | |
76 | printf '\062\170\234\143\147\0\0\0\20\0\10' | |
77 | return | |
78 | ;; | |
79 | e68fe8129b546b101aee9510c5328e7f21ca1d18) | |
80 | printf '\165\346\217\350\22\233\124\153\20\32\356' && | |
81 | printf '\225\20\305\62\216\177\41\312\35\30\170\234' && | |
82 | printf '\143\142\142\142\147\0\0\0\53\0\16' | |
83 | return | |
84 | ;; | |
db12505c | 85 | 5d8e6fc40f2dab00e6983a48523fe57e621f46434cb58dbd4422fba03380d886) |
86 | printf '\165\135\216\157\304\17\55\253\0\346\230\72' && | |
87 | printf '\110\122\77\345\176\142\37\106\103\114\265' && | |
88 | printf '\215\275\104\42\373\240\63\200\330\206\170\234' && | |
89 | printf '\143\142\142\142\147\0\0\0\53\0\16' | |
90 | return | |
91 | ;; | |
171bdaca JK |
92 | esac |
93 | ;; | |
de5737ca | 94 | # blob containing "\3\326" |
95 | 471819e8c52bf11513f100b2810a8aa0622d5cd3d1c913758a071dd4b3bad8fe) | |
96 | case "$2" in | |
97 | '') | |
98 | printf '\062\170\234\143\276\006\000\000\336\000\332' | |
99 | return | |
100 | ;; | |
101 | esac | |
171bdaca JK |
102 | esac |
103 | ||
73c3f0f7 JK |
104 | # If it's not a delta, we can convince pack-objects to generate a pack |
105 | # with just our entry, and then strip off the header (12 bytes) and | |
106 | # trailer (20 bytes). | |
107 | if test -z "$2" | |
108 | then | |
109 | echo "$1" | git pack-objects --stdout >pack_obj.tmp && | |
110 | size=$(wc -c <pack_obj.tmp) && | |
db12505c | 111 | dd if=pack_obj.tmp bs=1 count=$((size - $(test_oid rawsz) - 12)) skip=12 && |
73c3f0f7 JK |
112 | rm -f pack_obj.tmp |
113 | return | |
114 | fi | |
115 | ||
171bdaca JK |
116 | echo >&2 "BUG: don't know how to print $1${2:+ (from $2)}" |
117 | return 1 | |
118 | } | |
119 | ||
120 | # Compute and append pack trailer to "$1" | |
121 | pack_trailer () { | |
db12505c | 122 | test-tool $(test_oid algo) -b <"$1" >trailer.tmp && |
171bdaca JK |
123 | cat trailer.tmp >>"$1" && |
124 | rm -f trailer.tmp | |
125 | } | |
126 | ||
127 | # Remove any existing packs to make sure that | |
128 | # whatever we index next will be the pack that we | |
129 | # actually use. | |
130 | clear_packs () { | |
131 | rm -f .git/objects/pack/* | |
132 | } | |
db12505c | 133 | |
134 | test_oid_cache <<-EOF | |
135 | packlib_7_0 sha1:01d7713666f4de822776c7622c10f1b07de280dc | |
136 | packlib_7_0 sha256:37c8e2c15bb22b912e59b43fd51a4f7e9465ed0b5084c5a1411d991cbe630683 | |
137 | ||
138 | packlib_7_76 sha1:e68fe8129b546b101aee9510c5328e7f21ca1d18 | |
139 | packlib_7_76 sha256:5d8e6fc40f2dab00e6983a48523fe57e621f46434cb58dbd4422fba03380d886 | |
140 | EOF |