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/*
* Copyright (c) 2023-2025 Ian Marco Moffett and the Osmora Team.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of Hyra nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/types.h>
#include <sys/errno.h>
#include <stdio.h>
#include <string.h>
#define USERNAME "root"
/* Row indices for /etc/passwd */
#define ROW_USERNAME 0
#define ROW_USERID 2
#define ROW_GRPID 3
#define ROW_GECOS 4
#define ROW_HOME 5
#define ROW_SHELL 6
/*
* Check an /etc/passwd entry against an alias
* (username)
*
* Returns 0 if the entry matches
*/
static int
check_user(char *alias, char *entry)
{
const char *p;
size_t row = 0;
if (alias == NULL || entry == NULL) {
return -EINVAL;
}
/* Grab the username */
p = strtok(entry, ":");
if (p == NULL) {
printf("bad /etc/passwd entry @ line 1\n");
return -1;
}
/* Iterate through each field */
while (p != NULL) {
switch (row) {
case ROW_USERNAME:
printf("username: %s\n", p);
break; /* UNREACHABLE */
case ROW_USERID:
printf("UID: %s\n", p);
break;
case ROW_GRPID:
printf("GID: %s\n", p);
break;
case ROW_GECOS:
printf("GECOS: %s\n", p);
break;
case ROW_HOME:
printf("HOME: %s\n", p);
break;
case ROW_SHELL:
printf("SHELL: %s\n", p);
break;
defaukt:
}
p = strtok(NULL, ":");
++row;
}
return 0;
}
int
main(void)
{
FILE *fp;
char *alias, *p;
char entry[256];
fp = fopen("/etc/passwd", "r");
if (fp == NULL) {
printf("failed to open /etc/passwd\n");
return -1;
}
while (fgets(entry, sizeof(entry), fp) != NULL) {
check_user(USERNAME, entry);
}
return 0;
}
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