37 lines
675 B
C
37 lines
675 B
C
#define _BSD_SOURCE
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#include <errno.h>
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#include <pwd.h>
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#include <stdio.h>
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#include <sys/types.h>
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#include <unistd.h>
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int main(int argc, char **argv) {
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if(argc < 3) {
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fprintf(stderr, "Usage: %s username command [arguments]\n", argv[0]);
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return 1;
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}
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const char *username = argv[1];
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errno = 0;
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struct passwd *passwd_entry = getpwnam(username);
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if(passwd_entry == NULL) {
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perror("getpwnam");
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return 1;
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}
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uid_t ruid = passwd_entry->pw_uid;
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if(setreuid(ruid, -1) != 0) {
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perror("getpwnam");
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return 1;
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}
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char **daemon_argv = &argv[2];
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const char *daemon_command = daemon_argv[0];
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execvp(daemon_command, daemon_argv);
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perror("execvp");
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return 1;
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}
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