42 lines
703 B
C
42 lines
703 B
C
/* vim: tabstop=4 shiftwidth=4 noexpandtab
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*
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* Who Am I?
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*
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*/
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#include <stdio.h>
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#include <syscall.h>
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#include <string.h>
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#include <stdlib.h>
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DEFN_SYSCALL0(getuid, 23);
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#define LINE_LEN 4096
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int main(int argc, char ** argv) {
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FILE * passwd = fopen("/etc/passwd", "r");
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char line[LINE_LEN];
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int uid = syscall_getuid();
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while (fgets(line, LINE_LEN, passwd) != NULL) {
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line[strlen(line)-1] = '\0';
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char *p, *tokens[10], *last;
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int i = 0;
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for ((p = strtok_r(line, ":", &last)); p;
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(p = strtok_r(NULL, ":", &last)), i++) {
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if (i < 511) tokens[i] = p;
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}
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tokens[i] = NULL;
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if (atoi(tokens[2]) == uid) {
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printf("%s\n", tokens[0]);
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}
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}
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fclose(passwd);
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return 0;
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}
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