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| 40 |
#include <wait.h> |
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#include <wait.h> |
| 41 |
#include <errno.h> |
41 |
#include <errno.h> |
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#include <string.h> |
42 |
#include <string.h> |
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43 |
#include <fcntl.h> |
| 43 |
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44 |
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| 44 |
extern int errno; |
45 |
extern int errno; |
| 45 |
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46 |
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| 71 |
return 0; |
72 |
return 0; |
| 72 |
} |
73 |
} |
| 73 |
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74 |
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75 |
/* |
| 76 |
* Move file descriptor and mark as CLOSE-ON-EXEC. |
| 77 |
*/ |
| 78 |
static int move_fd(int oldfd, int newfd) { |
| 79 |
int flags; |
| 80 |
int tmpfd; |
| 81 |
|
| 82 |
if (oldfd != newfd) |
| 83 |
tmpfd = dup2(oldfd, newfd); |
| 84 |
else |
| 85 |
tmpfd = newfd; |
| 86 |
if (tmpfd != newfd) |
| 87 |
fatal_perror("Error dup2 failed\n"); |
| 88 |
flags = fcntl(tmpfd, F_GETFD); |
| 89 |
if (flags == -1) |
| 90 |
fatal_perror("Error getting tmpfd status\n"); |
| 91 |
flags |= FD_CLOEXEC; |
| 92 |
if (fcntl(tmpfd, F_SETFD, flags) == -1) |
| 93 |
fatal_perror("Error setting tmpfd status\n"); |
| 94 |
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| 95 |
return tmpfd; |
| 96 |
} |
| 97 |
|
| 98 |
/* |
| 99 |
* Open /dev/null on fd in mode given by flags. |
| 100 |
*/ |
| 101 |
static void open_dev_null(int fd, int flags) { |
| 102 |
int tmpfd; |
| 103 |
|
| 104 |
close(fd); /* ignore error if already closed. */ |
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tmpfd = open("/dev/null", flags); |
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if (tmpfd < 0) |
| 107 |
fatal_perror("Error opening /dev/null\n"); |
| 108 |
if (tmpfd != fd) { |
| 109 |
int ret; |
| 110 |
|
| 111 |
ret = dup2(tmpfd, fd); |
| 112 |
if (ret < 0) |
| 113 |
fatal_perror("Error dup2 failed\n"); |
| 114 |
ret = close(tmpfd); |
| 115 |
if (ret < 0) |
| 116 |
fatal_perror("Error closing fd\n"); |
| 117 |
} |
| 118 |
} |
| 119 |
|
| 120 |
/* |
| 121 |
* Clone FDs for client<->server communication inherited from SESSION_RSH |
| 122 |
* to private FDs and mark them as CLOSE-ON-EXEC. |
| 123 |
* Re-open STDIN and STDOUT as /dev/null to protect channel from non-protocol |
| 124 |
* data. STDERR uses a separate channel and needs not to be changed; keep it |
| 125 |
* for debugging. |
| 126 |
* |
| 127 |
* FD 3 and 4 are used to not mix with STDIN=0, STDOUT=1 and STDERR=2. |
| 128 |
* Don't use dup() after closing previous FDs with close()! |
| 129 |
*/ |
| 74 |
void init_server_pipes ( void ) |
130 |
void init_server_pipes ( void ) |
| 75 |
{ |
131 |
{ |
| 76 |
/* FIXME: what is fd 3? maybe use dup() instead */ |
132 |
send_fd = move_fd(STDOUT_FILENO, 3); |
| 77 |
send_fd = dup2 ( STDOUT_FILENO, 3 ); |
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| 78 |
if ( send_fd < 0 ) |
| 79 |
fatal_perror ( "dup failed" ); |
| 80 |
close ( STDOUT_FILENO ); |
| 81 |
if ( debug_level ) |
133 |
if ( debug_level ) |
| 82 |
debug_printf ( "to_client fd=%d\n", send_fd ); |
134 |
debug_printf ( "to_client fd=%d\n", send_fd ); |
| 83 |
/* FIXME: see above */ |
135 |
open_dev_null(STDOUT_FILENO, O_WRONLY); |
| 84 |
recv_fd = dup2 ( STDIN_FILENO, 4); |
136 |
|
| 85 |
if ( recv_fd < 0 ) |
137 |
recv_fd = move_fd(STDIN_FILENO, 4); |
| 86 |
fatal_perror ( "dup failed" ); |
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| 87 |
close ( STDIN_FILENO ); |
| 88 |
add_read_fd ( recv_fd, connection_read_handler ); |
138 |
add_read_fd ( recv_fd, connection_read_handler ); |
| 89 |
if ( debug_level ) |
139 |
if ( debug_level ) |
| 90 |
debug_printf ( "from_client fd=%d\n", recv_fd ); |
140 |
debug_printf ( "from_client fd=%d\n", recv_fd ); |
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141 |
open_dev_null(STDIN_FILENO, O_RDONLY); |
| 142 |
|
| 91 |
return; |
143 |
return; |
| 92 |
} |
144 |
} |
| 93 |
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145 |
|