Subversion Repositories planix.SVN

#include <u.h>
#include <libc.h>
#include <auth.h>
#include "httpd.h"
#include "httpsrv.h"

static char*    readfile(char*);

/*
 * these should be done better; see the response codes in /lib/rfc/rfc2616 for
 * more info on what should be included.
 */
#define UNAUTHED        "You are not authorized to see this area.\n"

/*
 * check for authorization for some parts of the server tree.
 * the user name supplied with the authorization request is ignored;
 * instead, we authenticate as the realm's user.
 *
 * authorization should be done before opening any files so that
 * unauthorized users don't get to validate file names.
 *
 * returns 1 if authorized, 0 if unauthorized, -1 for io failure.
 */
int
authorize(HConnect *c, char *file)
{
        char *p, *p0;
        Hio *hout;
        char *buf;
        int i, n;
        char *t[257];

        p0 = halloc(c, strlen(file)+STRLEN("/.httplogin")+1);
        strcpy(p0, file);
        for(;;){
                p = strrchr(p0, '/');
                if(p == nil)
                        return hfail(c, HInternal);
                if(*(p+1) != 0)
                        break;

                /* ignore trailing '/'s */
                *p = 0;
        }
        strcpy(p, "/.httplogin");

        buf = readfile(p0);
        if(buf == nil){
                return 1;
        }
        n = tokenize(buf, t, nelem(t));
        
        if(c->head.authuser != nil && c->head.authpass != 0){
                for(i = 1; i+1 < n; i += 2){
                        if(strcmp(t[i], c->head.authuser) == 0
                        && strcmp(t[i+1], c->head.authpass) == 0){
                                free(buf);
                                return 1;
                        }
                }
        }

        hout = &c->hout;
        hprint(hout, "%s 401 Unauthorized\r\n", hversion);
        hprint(hout, "Server: Plan9\r\n");
        hprint(hout, "Date: %D\r\n", time(nil));
        hprint(hout, "WWW-Authenticate: Basic realm=\"%s\"\r\n", t[0]);
        hprint(hout, "Content-Type: text/html\r\n");
        hprint(hout, "Content-Length: %d\r\n", STRLEN(UNAUTHED));
        if(c->head.closeit)
                hprint(hout, "Connection: close\r\n");
        else if(!http11(c))
                hprint(hout, "Connection: Keep-Alive\r\n");
        hprint(hout, "\r\n");
        if(strcmp(c->req.meth, "HEAD") != 0)
                hprint(hout, "%s", UNAUTHED);
        writelog(c, "Reply: 401 Unauthorized\n");
        free(buf);
        return hflush(hout);
}

static char*
readfile(char *file)
{
        Dir *d;
        int fd;
        char *buf;
        int n, len;

        fd = open(file, OREAD);
        if(fd < 0)
                return nil;
        d = dirfstat(fd);
        if(d == nil){           /* shouldn't happen */
                close(fd);
                return nil;
        }
        len = d->length;
        free(d);

        buf = malloc(len+1);
        if(buf == 0){
                close(fd);
                return nil;
        }

        n = readn(fd, buf, len);
        close(fd);
        if(n <= 0){
                free(buf);
                return nil;
        }
        buf[n] = '\0';
        return buf;
}