acmecert: Fix cryptography bugs.

[utils.git] / krb5mapcc.c

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <ctype.h>
#include <dirent.h>
#include <fcntl.h>
#include <string.h>

int isnumeric(char *str)
{
    while(*str) {
	if(!isdigit(*str))
	    return(0);
	str++;
    }
    return(1);
}

char *findcc(int fd)
{
    int ret, dlen;
    static char retbuf[1024];
    char readbuf[1024];
    char *p, *p2;
    
    dlen = 0;
    p = readbuf;
    do {
	if(dlen == 1024)
	    dlen = 0;
	ret = read(fd, readbuf + dlen, sizeof(readbuf) - dlen);
	if(ret < 0) {
	    perror("read environ");
	    return(NULL);
	}
	dlen += ret;
	
	while((p = memchr(readbuf, 0, dlen)) != NULL) {
	    if((p2 = strchr(readbuf, '=')) != NULL) {
		*(p2++) = 0;
		if(!strcasecmp(readbuf, "KRB5CCNAME") && !strncasecmp(p2, "FILE:", 5)) {
		    if(strlen(p2 + 5) >= sizeof(retbuf)) {
			fprintf(stderr, "really long ccname!\n");
			return(NULL);
		    }
		    strcpy(retbuf, p2 + 5);
		    return(retbuf);
		}
	    }
	    p++;
	    memmove(readbuf, p, dlen -= (p - readbuf));
	}
    } while(ret != 0);
    return(NULL);
}

int main(int argc, char **argv)
{
    int fd;
    DIR *proc;
    struct dirent *de;
    char envbuf[1024];
    char *p, *cc;
    
    if((proc = opendir("/proc")) == NULL) {
	perror("/proc");
	exit(1);
    }
    while((de = readdir(proc)) != NULL) {
	if(!isnumeric(de->d_name))
	    continue;
	if(strlen(de->d_name) > 30)
	    continue;
	
	p = envbuf;
	strcpy(p, "/proc/");
	p += 6;
	strcpy(p, de->d_name);
	p += strlen(de->d_name);
	*(p++) = '/';
	strcpy(p, "environ");
	
	if((fd = open(envbuf, O_RDONLY)) < 0)
	    continue;
	cc = findcc(fd);
	close(fd);
	
	if(cc != NULL) {
	    printf("%s %s\n", de->d_name, cc);
	}
    }
    closedir(proc);
    return(0);
}