/*      $NetBSD: quip_server.c,v 1.7 2024/10/04 15:37:00 rillig Exp $   */
/*      $KAME: quip_server.c,v 1.6 2001/08/20 06:41:32 kjc Exp $        */
/*
 * Copyright (C) 1999-2000
 *      Sony Computer Science Laboratories, Inc.  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.
 *
 * THIS SOFTWARE IS PROVIDED BY SONY CSL 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 SONY CSL 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/param.h>
#include <sys/socket.h>
#include <sys/queue.h>

#include <net/if.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <stddef.h>
#include <string.h>
#include <errno.h>
#include <err.h>

#include <altq/altq.h>
#include <altq/altq_red.h>
#include <altq/altq_rio.h>

#include "altq_qop.h"
#include "quip_server.h"

extern LIST_HEAD(qop_iflist, ifinfo)    qop_iflist;

#define EQUAL(s1, s2)   (strcmp((s1), (s2)) == 0)

static int next_word(char **, char *);

static int query_list(const char *, const char *, char *, size_t);
static int query_handle2name(const char *, const char *, char *, size_t);
static int query_qdisc(const char *, const char *, char *, size_t);
static int query_filterspec(const char *, const char *, char *, size_t);

int
quip_input(FILE *fp)
{
        char request[REQ_MAXSIZE], result[RES_MAXSIZE], body[BODY_MAXSIZE],
            w[REQ_MAXSIZE], *cp, *query;
        int n = 0;

        while (1) {
                if (fgets(request, REQ_MAXSIZE, fp) == NULL)  /* EOF */
                        return (-1);
                /* skip preceding blank lines */
                if (request[0] == '\n')
                        continue;
                break;
        }

        /* remove trailing newline and white space */
        if ((cp = strrchr(request, '\n')) != NULL) {
                *cp-- = '\0';
                while (*cp == ' ' || *cp == '\t')
                        *cp-- = '\0';
        }

        body[0] = '\0';
        cp = request;
        if (!next_word(&cp, w)) {
                snprintf(result, sizeof(result), "400 Bad request\n");
                goto done;
        }
        if (EQUAL(w, "GET")) {
                if (!next_word(&cp, w)) {
                        snprintf(result, sizeof(result), "400 Bad request\n");
                        goto done;
                }
                if ((query = strchr(w, '?')) != NULL) {
                        /* request has a query string */
                        *query = '\0';
                        query++;
                }

                if (EQUAL(w, "list")) {
                        n = query_list(w, query, body, BODY_MAXSIZE);
                } else if (EQUAL(w, "handle-to-name")) {
                        n = query_handle2name(w, query, body, BODY_MAXSIZE);
                } else if (EQUAL(w, "qdisc")) {
                        n = query_qdisc(w, query, body, BODY_MAXSIZE);
                } else if (EQUAL(w, "filter")) {
                        n = query_filterspec(w, query, body, BODY_MAXSIZE);
                } else {
                        snprintf(result, sizeof(result), "400 Bad request\n");
                        goto done;
                }
        } else {
                snprintf(result, sizeof(result), "400 Bad request\n");
                goto done;
        }

        if (n == 0) {
                snprintf(result, sizeof(result), "204 No content\n");
        } else if (n < 0) {
                snprintf(result, sizeof(result), "400 Bad request\n");
        } else {
                snprintf(result, sizeof(result), "200 OK\nContent-Length:%d\n", n);
        }

  done:
        /* send a result line and a blank line */
        if (fputs ("QUIP/1.0 ", fp) != 0 ||
            fputs(result, fp) != 0 || fputs("\n", fp) != 0)
                return (-1);

        /* send message body */
        if (fputs(body, fp) != 0)
                return (-1);
        return (0);
}

/*
 * Skip leading blanks, then copy next word (delimited by blank or zero, but
 * no longer than 63 bytes) into buffer b, set scan pointer to following 
 * non-blank (or end of string), and return 1.  If there is no non-blank text,
 * set scan ptr to point to 0 byte and return 0.
 */
static int 
next_word(char **cpp, char *b)
{
        char           *tp;
        int             L;

        *cpp += strspn(*cpp, " \t");
        if (**cpp == '\0' || **cpp == '\n' || **cpp == '#')
                return(0);

        tp = strpbrk(*cpp, " \t\n#");
        L = MIN((tp)?(tp-*cpp):(int)strlen(*cpp), 63);
        strncpy(b, *cpp, L);
        *(b + L) = '\0';
        *cpp += L;
        *cpp += strspn(*cpp, " \t");
        return (1);
}


/*
 * expand_classname creates a long class name.
 *   <ifname>:/<root_name>/../<parent_name>/<class_name>
 */
static int
expand_classname(struct classinfo *clinfo, char *name, size_t maxname)
{
        struct classinfo *ci = clinfo;
#define CLASSNAMEMAX    256
        char buf[2][CLASSNAMEMAX], *b0, *b1, *tmp;

        b0 = buf[0]; b1 = buf[1];
        b1[0] = '\0';
        while (ci != NULL) {
                strlcpy(b0, "/", CLASSNAMEMAX);
                strlcat(b0, ci->clname, CLASSNAMEMAX);
                strlcat(b0, b1, CLASSNAMEMAX);

                ci = ci->parent;
                tmp = b0; b0 = b1; b1 = tmp;
        }
        snprintf(b0, CLASSNAMEMAX, "%s:", clinfo->ifinfo->ifname);
        strlcat(b0, b1, CLASSNAMEMAX);
        strlcpy(name, b0, CLASSNAMEMAX);
        return (strlen(name));
#undef CLASSNAMEMAX
}

/*
 * expand_filtername creates a long filter name.
 *   <ifname>:/<root_name>/../<parent_name>/<class_name>:<fltr_name>
 */
static int
expand_filtername(struct fltrinfo *fltrinfo, char *name, size_t maxname)
{
        int len;

        len = expand_classname(fltrinfo->clinfo, name, maxname);
        snprintf(name + len, maxname - len, ":%s", fltrinfo->flname);
        return (strlen(name));
}

static int
query_handle2name(const char *cmd, const char *arg, char *msg, size_t maxmsg)
{
        struct ifinfo *ifinfo;
        struct classinfo *clinfo;
        struct fltrinfo *fltrinfo;
        char *ifname, *class_field, *fltr_field, buf[256], *cp;
        u_long handle;

        strlcpy(buf, arg, sizeof(buf));
        cp = buf;
        ifname = strsep(&cp, ":");
        class_field = strsep(&cp, ":");
        fltr_field = cp;

        if (fltr_field != NULL) {
                if (sscanf(fltr_field, "%lx", &handle) != 1)
                        return (-1);
                if ((ifinfo = ifname2ifinfo(ifname)) == NULL)
                        return (-1);
                if ((fltrinfo = flhandle2fltrinfo(ifinfo, handle)) == NULL)
                        return (-1);

                (void)expand_filtername(fltrinfo, msg, maxmsg);
        } else {
                if (sscanf(class_field, "%lx", &handle) != 1)
                        return (-1);
                if ((ifinfo = ifname2ifinfo(ifname)) == NULL)
                        return (-1);
                if ((clinfo = clhandle2clinfo(ifinfo, handle)) == NULL)
                                return (-1);

                (void)expand_classname(clinfo, msg, maxmsg);
        }
        strlcat(msg, "\n", maxmsg);
        return (strlen(msg));
}

static int
query_qdisc(const char *cmd, const char *arg, char *msg, size_t maxmsg)
{
        struct ifinfo *ifinfo;

        if ((ifinfo = ifname2ifinfo(arg)) == NULL)
                return (-1);

        snprintf(msg, maxmsg, "%s\nbandwidth:%.2fMbps\nstatus:%s\n",
                 ifinfo->qdisc->qname, (double)ifinfo->bandwidth/1000000,
                        (ifinfo->enabled ? "enabled" : "disabled"));
        return (strlen(msg));
}

static int
query_filterspec(const char *cmd, const char *arg, char *msg, size_t maxmsg)
{
        struct ifinfo *ifinfo;
        struct fltrinfo *fltrinfo;
        struct flow_filter *filt;
        char *ifname, *fltr_field, buf[256], *cp;
        u_long handle;

        strlcpy(buf, arg, sizeof(buf));
        cp = buf;
        ifname = strsep(&cp, ":");
        (void)strsep(&cp, ":");
        fltr_field = cp;

        if (fltr_field == NULL)
                return (-1);
        if (sscanf(fltr_field, "%lx", &handle) != 1)
                return (-1);

        if ((ifinfo = ifname2ifinfo(ifname)) == NULL)
                return (-1);
        if ((fltrinfo = flhandle2fltrinfo(ifinfo, handle)) == NULL)
                return (-1);

        filt = &fltrinfo->fltr;
        
        if (filt->ff_flow.fi_family == AF_INET) {
                char src[128], dst[128], smask[128], dmask[128], tos[128];

                if (filt->ff_flow.fi_dst.s_addr == 0) {
                        snprintf(dst, sizeof(dst), "0");
                        dmask[0] = '\0';
                } else {
                        snprintf(dst, sizeof(dst), "%s",
                                 inet_ntoa(filt->ff_flow.fi_dst));
                        if (filt->ff_mask.mask_dst.s_addr == 0xffffffff)
                                dmask[0] = '\0';
                        else
                                snprintf(dmask, sizeof(dmask), " mask %#x",
                                         ntoh32(filt->ff_mask.mask_dst.s_addr));
                }
                if (filt->ff_flow.fi_src.s_addr == 0) {
                        snprintf(src, sizeof(src), "0");
                        smask[0] = '\0';
                } else {
                        snprintf(src, sizeof(src), "%s",
                                 inet_ntoa(filt->ff_flow.fi_src));
                        if (filt->ff_mask.mask_src.s_addr == 0xffffffff)
                                smask[0] = '\0';
                        else
                                snprintf(smask, sizeof(smask), " mask %#x",
                                         ntoh32(filt->ff_mask.mask_src.s_addr));
                }
                if (filt->ff_flow.fi_tos == 0)
                        tos[0] = '\0';
                else
                        snprintf(tos, sizeof(tos), " tos %#x tosmask %#x",
                                 filt->ff_flow.fi_tos,
                                 filt->ff_mask.mask_tos);

                snprintf(msg, maxmsg, "inet %s%s %d %s%s %d %d%s\n",
                         dst, dmask,
                         ntoh16(filt->ff_flow.fi_dport),
                         src, smask,
                         ntoh16(filt->ff_flow.fi_sport),
                         filt->ff_flow.fi_proto, tos);
        }
#ifdef INET6
        else if (filt->ff_flow.fi_family == AF_INET6) {
                struct flow_filter6 *filt6;
                char dst6[INET6_ADDRSTRLEN], dmask6[INET6_ADDRSTRLEN];
                char src6[INET6_ADDRSTRLEN], smask6[INET6_ADDRSTRLEN];
                char tclass6[128];
                const struct in6_addr mask128 = 
                {{{ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
                  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }}};

                filt6 = (struct flow_filter6 *)&fltrinfo->fltr;
                if (IN6_IS_ADDR_UNSPECIFIED(&filt6->ff_flow6.fi6_dst)) {
                        snprintf(dst6, sizeof(dst6), "0");
                        dmask6[0] = '\0';
                } else {
                        inet_ntop(AF_INET6, &filt6->ff_flow6.fi6_dst,
                                  dst6, sizeof(dst6));
                        if (IN6_ARE_ADDR_EQUAL(&mask128,
                                               &filt6->ff_mask6.mask6_dst))
                                dmask6[0] = '\0';
                        else {
                                snprintf(dmask6, sizeof(dmask6), " mask ");
                                inet_ntop(AF_INET6, &filt6->ff_mask6.mask6_dst,
                                          dmask6 + 6, sizeof(dmask6) -6);
                        }
                }

                if (IN6_IS_ADDR_UNSPECIFIED(&filt6->ff_flow6.fi6_src)) {
                        snprintf(src6, sizeof(src6), "0");
                        smask6[0] = '\0';
                } else {
                        inet_ntop(AF_INET6, &filt6->ff_flow6.fi6_src,
                                  src6, sizeof(src6));
                        if (IN6_ARE_ADDR_EQUAL(&mask128,
                                               &filt6->ff_mask6.mask6_src))
                                smask6[0] = '\0';
                        else {
                                snprintf(smask6, sizeof(smask6), " mask ");
                                inet_ntop(AF_INET6, &filt6->ff_mask6.mask6_src,
                                          smask6 + 6, sizeof(smask6) -6);
                        }
                }
                if (filt6->ff_flow6.fi6_tclass == 0)
                        tclass6[0] = '\0';
                else
                        snprintf(tclass6, sizeof(tclass6),
                                 " tclass %#x tclassmask %#x",
                                 filt6->ff_flow6.fi6_tclass,
                                 filt6->ff_mask6.mask6_tclass);

                snprintf(msg, maxmsg, "inet6 %s%s %d %s%s %d %d%s\n",
                         dst6, dmask6,
                         ntoh16(filt6->ff_flow6.fi6_dport),
                         src6, smask6,
                         ntoh16(filt6->ff_flow6.fi6_sport),
                         filt6->ff_flow6.fi6_proto, tclass6);
        }
#endif /* INET6 */

        return (strlen(msg));
}


/*
 * string_match compares 2 strings and returns 1 when s1 matches s2.
 *      s1: possibly includes wildcards, "*".
 *      s2: must be a full string (should not include "*").
 */
static int
string_match(const char *s1, const char *s2)
{
        char *ap, *next, sub[256];
        int prefixlen, sublen;

        /* if there's no wild card, compare full string */
        if ((ap = strchr(s1, '*')) == NULL)
                return (strcmp(s1, s2) == 0);

        /* compare string prefix */
        prefixlen = ap - s1;
        if (strncmp(s1, s2, prefixlen) != 0)
                return (0);
        s2 += prefixlen;

        /*
         * if there is another wildcard in the rest of the string,
         * compare the substring between the 2 wildcards.
         */
        while ((next = strchr(ap + 1, '*')) != NULL) {
                sublen = next - ap - 1;
                strncpy(sub, ap+1, sublen);
                sub[sublen] = '\0';
                if ((s2 = strstr(s2, sub)) == NULL)
                        return (0);

                s2 += sublen;
                ap = next;
        }

        /* no more wildcard, compare the rest of the string */
        return (strcmp(ap+1, s2+strlen(s2)-strlen(ap+1)) == 0);
}

static int
query_list(const char *cmd, const char *arg, char *msg, size_t maxmsg)
{
        const char *colon;
        char tmp[256], *cp, *ep;
        struct ifinfo *ifinfo;
        struct classinfo *clinfo;
        struct fltrinfo *fltrinfo;
        int print_if, print_class, print_fltr, len;

        if (arg == NULL) {
                /* no arg, print all */
                print_if = print_class = print_fltr = 1;
        } else {
                print_if = print_class = print_fltr = 0;
                if ((colon = strchr(arg, ':')) == NULL)
                        print_if = 1;
                else if (strchr(colon+1, ':') == NULL)
                        print_class = 1;
                else
                        print_fltr = 1;
        }

        cp = msg;
        ep = msg + maxmsg;
        LIST_FOREACH(ifinfo, &qop_iflist, next) {
                if (print_if) {
                        strlcpy(tmp, ifinfo->ifname, sizeof(tmp));
                        if (arg == NULL || string_match(arg, tmp)) {
                                len = snprintf(cp, ep - cp, "%#010x\t%s\n",
                                               ifinfo->ifindex, tmp);
                                if (len < 0 || len >= ep - cp)
                                        break;
                                cp += len;
                        }
                }
                if (!print_class && !print_fltr)
                        continue;
                for (clinfo = get_rootclass(ifinfo);
                          clinfo != NULL; clinfo = get_nextclass(clinfo)) {
                        if (print_class) {
                                expand_classname(clinfo, tmp, sizeof(tmp));
                                if (arg == NULL || string_match(arg, tmp)) {
                                        len = snprintf(cp, ep - cp,
                                                       "%#010lx\t%s\n",
                                                       clinfo->handle, tmp);
                                        if (len < 0 || len >= ep - cp)
                                                break;
                                        cp += len;
                                }
                        }
                        if (!print_fltr)
                                continue;
                        LIST_FOREACH(fltrinfo, &clinfo->fltrlist, next) {
                                expand_filtername(fltrinfo, tmp, sizeof(tmp));
                                if (arg == NULL || string_match(arg, tmp)) {
                                        len = snprintf(cp, ep - cp, "%#010lx\t%s\n",
                                                       fltrinfo->handle, tmp);
                                        if (len < 0 || len >= ep - cp)
                                                break;
                                        cp += len;
                                }
                        }
                }
        }
        return (strlen(msg));
}