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* along with this program. If not, see
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20
* <http://www.gnu.org/licenses/>.
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* Contact the authors at <https://www.fukt.bsnet.se/~belorn/> and
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* <https://www.fukt.bsnet.se/~teddy/>.
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* Contact the authors at <mandos@recompile.se>.
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25
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY() */
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#include <sys/types.h> /* ssize_t */
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#include <sys/types.h> /* uid_t, gid_t, ssize_t */
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#include <sys/stat.h> /* mkfifo(), S_IRUSR, S_IWUSR */
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#include <iso646.h> /* and */
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#include <errno.h> /* errno, EEXIST */
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#include <stdio.h> /* perror() */
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#include <stdlib.h> /* EXIT_FAILURE, NULL, size_t, free(),
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#include <errno.h> /* errno, EACCES, ENOTDIR, ELOOP,
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ENAMETOOLONG, ENOSPC, EROFS,
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ENOENT, EEXIST, EFAULT, EMFILE,
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ENFILE, ENOMEM, EBADF, EINVAL, EIO,
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#include <error.h> /* error() */
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#include <stdio.h> /* fprintf(), vfprintf(),
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#include <stdlib.h> /* EXIT_FAILURE, NULL, size_t, free(),
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realloc(), EXIT_SUCCESS */
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#include <fcntl.h> /* open(), O_RDONLY */
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#include <unistd.h> /* read(), close(), write(),
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#include <sysexits.h> /* EX_OSERR, EX_OSFILE,
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EX_UNAVAILABLE, EX_IOERR */
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#include <string.h> /* strerror() */
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#include <stdarg.h> /* va_list, va_start(), ... */
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/* Function to use when printing errors */
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__attribute__((format (gnu_printf, 3, 4)))
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void error_plus(int status, int errnum, const char *formatstring,
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va_start(ap, formatstring);
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ret = vasprintf(&text, formatstring, ap);
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fprintf(stderr, "Mandos plugin %s: ",
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program_invocation_short_name);
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vfprintf(stderr, formatstring, ap);
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fprintf(stderr, ": ");
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fprintf(stderr, "%s\n", strerror(errnum));
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error(status, errno, "vasprintf while printing error");
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fprintf(stderr, "Mandos plugin ");
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error(status, errnum, "%s", text);
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74
int main(__attribute__((unused))int argc,
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75
__attribute__((unused))char **argv){
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83
const char passfifo[] = "/lib/cryptsetup/passfifo";
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ret = TEMP_FAILURE_RETRY(mkfifo(passfifo, S_IRUSR | S_IWUSR));
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if(ret == -1 and errno != EEXIST){
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ret = mkfifo(passfifo, S_IRUSR | S_IWUSR);
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error_plus(EX_OSFILE, errno, "mkfifo");
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error_plus(EX_OSERR, errno, "mkfifo");
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/* no "/lib/cryptsetup"? */
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error_plus(EX_UNAVAILABLE, errno, "mkfifo");
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break; /* not an error */
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int fifo_fd = TEMP_FAILURE_RETRY(open(passfifo, O_RDONLY));
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int fifo_fd = open(passfifo, O_RDONLY);
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107
if(fifo_fd == -1){
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error_plus(0, errno, "open");
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return EX_UNAVAILABLE;
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/* Lower group privileges */
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if(setgid(gid) == -1){
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error_plus(0, errno, "setgid");
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/* Lower user privileges */
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if(setuid(uid) == -1){
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error_plus(0, errno, "setuid");
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137
/* Read from FIFO */
63
141
size_t buf_allocated = 0;
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142
const size_t blocksize = 1024;
66
144
if(buf_len + blocksize > buf_allocated){
67
145
char *tmp = realloc(buf, buf_allocated + blocksize);
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error_plus(0, errno, "realloc");
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152
buf_allocated += blocksize;
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sret = TEMP_FAILURE_RETRY(read(fifo_fd, buf + buf_len,
77
buf_allocated - buf_len));
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sret = read(fifo_fd, buf + buf_len, buf_allocated - buf_len);
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error_plus(0, errno, "read");
169
return EX_UNAVAILABLE;
83
172
buf_len += (size_t)sret;
88
TEMP_FAILURE_RETRY(close(fifo_fd));
90
179
/* Print password to stdout */
91
180
size_t written = 0;
92
181
while(written < buf_len){
93
sret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buf + written,
182
sret = write(STDOUT_FILENO, buf + written, buf_len - written);
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error_plus(0, errno, "write");
100
200
written += (size_t)sret;
204
ret = close(STDOUT_FILENO);
207
error_plus(0, errno, "close");
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216
return EXIT_SUCCESS;