blob: 3b7d1ea2168adda92b88f88e8b67fd06371099b8
1 | /* vi: set sw=4 ts=4: */ |
2 | /* |
3 | * Licensed under GPLv2 or later, see file LICENSE in this source tree. |
4 | */ |
5 | |
6 | #include "libbb.h" |
7 | #include "bb_archive.h" |
8 | |
9 | enum { |
10 | //TAR_FILETYPE, |
11 | TAR_MODE, |
12 | TAR_FILENAME, |
13 | TAR_REALNAME, |
14 | #if ENABLE_FEATURE_TAR_UNAME_GNAME |
15 | TAR_UNAME, |
16 | TAR_GNAME, |
17 | #endif |
18 | TAR_SIZE, |
19 | TAR_UID, |
20 | TAR_GID, |
21 | TAR_MAX, |
22 | }; |
23 | |
24 | static const char *const tar_var[] = { |
25 | // "FILETYPE", |
26 | "MODE", |
27 | "FILENAME", |
28 | "REALNAME", |
29 | #if ENABLE_FEATURE_TAR_UNAME_GNAME |
30 | "UNAME", |
31 | "GNAME", |
32 | #endif |
33 | "SIZE", |
34 | "UID", |
35 | "GID", |
36 | }; |
37 | |
38 | static void xputenv(char *str) |
39 | { |
40 | if (putenv(str)) |
41 | bb_error_msg_and_die("%s", bb_msg_memory_exhausted); |
42 | } |
43 | |
44 | static void str2env(char *env[], int idx, const char *str) |
45 | { |
46 | env[idx] = xasprintf("TAR_%s=%s", tar_var[idx], str); |
47 | xputenv(env[idx]); |
48 | } |
49 | |
50 | static void dec2env(char *env[], int idx, unsigned long long val) |
51 | { |
52 | env[idx] = xasprintf("TAR_%s=%llu", tar_var[idx], val); |
53 | xputenv(env[idx]); |
54 | } |
55 | |
56 | static void oct2env(char *env[], int idx, unsigned long val) |
57 | { |
58 | env[idx] = xasprintf("TAR_%s=%lo", tar_var[idx], val); |
59 | xputenv(env[idx]); |
60 | } |
61 | |
62 | void FAST_FUNC data_extract_to_command(archive_handle_t *archive_handle) |
63 | { |
64 | file_header_t *file_header = archive_handle->file_header; |
65 | |
66 | #if ENABLE_FEATURE_TAR_SELINUX |
67 | char *sctx = archive_handle->tar__sctx[PAX_NEXT_FILE]; |
68 | if (!sctx) |
69 | sctx = archive_handle->tar__sctx[PAX_GLOBAL]; |
70 | if (sctx) { /* setfscreatecon is 4 syscalls, avoid if possible */ |
71 | setfscreatecon(sctx); |
72 | free(archive_handle->tar__sctx[PAX_NEXT_FILE]); |
73 | archive_handle->tar__sctx[PAX_NEXT_FILE] = NULL; |
74 | } |
75 | #endif |
76 | |
77 | if ((file_header->mode & S_IFMT) == S_IFREG) { |
78 | pid_t pid; |
79 | int p[2], status; |
80 | char *tar_env[TAR_MAX]; |
81 | |
82 | memset(tar_env, 0, sizeof(tar_env)); |
83 | |
84 | xpipe(p); |
85 | pid = BB_MMU ? xfork() : xvfork(); |
86 | if (pid == 0) { |
87 | /* Child */ |
88 | /* str2env(tar_env, TAR_FILETYPE, "f"); - parent should do it once */ |
89 | oct2env(tar_env, TAR_MODE, file_header->mode); |
90 | str2env(tar_env, TAR_FILENAME, file_header->name); |
91 | str2env(tar_env, TAR_REALNAME, file_header->name); |
92 | #if ENABLE_FEATURE_TAR_UNAME_GNAME |
93 | str2env(tar_env, TAR_UNAME, file_header->tar__uname); |
94 | str2env(tar_env, TAR_GNAME, file_header->tar__gname); |
95 | #endif |
96 | dec2env(tar_env, TAR_SIZE, file_header->size); |
97 | dec2env(tar_env, TAR_UID, file_header->uid); |
98 | dec2env(tar_env, TAR_GID, file_header->gid); |
99 | close(p[1]); |
100 | xdup2(p[0], STDIN_FILENO); |
101 | signal(SIGPIPE, SIG_DFL); |
102 | execl(archive_handle->tar__to_command_shell, |
103 | archive_handle->tar__to_command_shell, |
104 | "-c", |
105 | archive_handle->tar__to_command, |
106 | (char *)0); |
107 | bb_perror_msg_and_die("can't execute '%s'", archive_handle->tar__to_command_shell); |
108 | } |
109 | close(p[0]); |
110 | /* Our caller is expected to do signal(SIGPIPE, SIG_IGN) |
111 | * so that we don't die if child don't read all the input: */ |
112 | bb_copyfd_exact_size(archive_handle->src_fd, p[1], -file_header->size); |
113 | close(p[1]); |
114 | |
115 | status = wait_for_exitstatus(pid); |
116 | if (WIFEXITED(status) && WEXITSTATUS(status)) |
117 | bb_error_msg_and_die("'%s' returned status %d", |
118 | archive_handle->tar__to_command, WEXITSTATUS(status)); |
119 | if (WIFSIGNALED(status)) |
120 | bb_error_msg_and_die("'%s' terminated by signal %d", |
121 | archive_handle->tar__to_command, WTERMSIG(status)); |
122 | |
123 | if (!BB_MMU) { |
124 | int i; |
125 | for (i = 0; i < TAR_MAX; i++) { |
126 | if (tar_env[i]) |
127 | bb_unsetenv_and_free(tar_env[i]); |
128 | } |
129 | } |
130 | } |
131 | |
132 | #if 0 /* ENABLE_FEATURE_TAR_SELINUX */ |
133 | if (sctx) |
134 | /* reset the context after creating an entry */ |
135 | setfscreatecon(NULL); |
136 | #endif |
137 | } |
138 |