GCOV - Varnish Cache


/*-
 * Copyright (c) 2006 Verdens Gang AS
 * Copyright (c) 2006-2017 Varnish Software AS
 * All rights reserved.
 *
 * Author: Poul-Henning Kamp <phk@phk.freebsd.dk>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * 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 THE AUTHOR 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 AUTHOR 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.
 *
 * HTTP request storage and manipulation
 */

#include "config.h"

#include "cache_varnishd.h"
#include <stdio.h>
#include <stdlib.h>

#include "common/heritage.h"

#include "vct.h"
#include "vend.h"
#include "vnum.h"
#include "vtim.h"

#define BODYSTATUS(U, l, n, a, k)                               \
        const struct body_status BS_##U[1] = {{                 \
                .name = #l,                                     \
                .nbr = n,                                       \
                .avail = a,                                     \
                .length_known = k                               \
        }};
#include "tbl/body_status.h"


#define HTTPH(a, b, c) char b[] = "*" a ":";
#include "tbl/http_headers.h"

const char H__Status[]  = "\010:status:";
const char H__Proto[]   = "\007:proto:";
const char H__Reason[]  = "\010:reason:";

static char * via_hdr;

/*--------------------------------------------------------------------
 * Perfect hash to rapidly recognize headers from tbl/http_headers.h
 * which have non-zero flags.
 *
 * A suitable algorithm can be found with `gperf`:
 *
 *      tr '" ,' '   ' < include/tbl/http_headers.h |
 *              awk '$1 == "H(" {print $2}' |
 *              gperf --ignore-case
 *
 */

#define GPERF_MIN_WORD_LENGTH 2
#define GPERF_MAX_WORD_LENGTH 19
#define GPERF_MAX_HASH_VALUE 79

static const unsigned char http_asso_values[256] = {
        80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
        80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
        80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
        80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
        80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
        80, 80, 80,  0, 80, 80, 80, 80, 80, 80,
        80, 80, 80, 80, 80,  5, 80, 20,  0,  0,
        5, 10,  5,  5, 80,  0, 15,  0, 20, 80,
        40, 80,  0, 35, 10, 20, 55, 45,  0,  0,
        80, 80, 80, 80, 80, 80, 80,  5, 80, 20,
        0,  0,  5, 10,  5,  5, 80,  0, 15,  0,
        20, 80, 40, 80,  0, 35, 10, 20, 55, 45,
        0,  0, 80, 80, 80, 80, 80, 80, 80, 80,
        80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
        80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
        80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
        80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
        80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
        80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
        80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
        80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
        80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
        80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
        80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
        80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
        80, 80, 80, 80, 80, 80
};

static struct http_hdrflg {
        char            *hdr;
        unsigned        flag;
} http_hdrflg[GPERF_MAX_HASH_VALUE + 1] = {
        { NULL }, { NULL }, { NULL }, { NULL },
        { H_Date },
        { H_Range },
        { NULL },
        { H_Referer },
        { H_Age },
        { H_From },
        { H_Keep_Alive },
        { H_Retry_After },
        { H_TE },
        { H_If_Range },
        { H_ETag },
        { H_X_Forwarded_For },
        { H_Expect },
        { H_Trailer },
        { H_If_Match },
        { H_Host },
        { H_Accept_Language },
        { H_Accept },
        { H_If_Modified_Since },
        { H_If_None_Match },
        { H_If_Unmodified_Since },
        { NULL },
        { H_Cookie },
        { H_Upgrade },
        { H_Last_Modified },
        { H_Accept_Charset },
        { H_Accept_Encoding },
        { H_Content_MD5 },
        { H_Content_Type },
        { H_Content_Range },
        { NULL }, { NULL },
        { H_Content_Language },
        { H_Transfer_Encoding },
        { H_Authorization },
        { H_Content_Length },
        { H_User_Agent },
        { H_Server },
        { H_Expires },
        { H_Location },
        { NULL },
        { H_Set_Cookie },
        { H_Content_Encoding },
        { H_Max_Forwards },
        { H_Cache_Control },
        { NULL },
        { H_Connection },
        { H_Pragma },
        { NULL },
        { H_Accept_Ranges },
        { H_HTTP2_Settings },
        { H_Allow },
        { H_Content_Location },
        { NULL },
        { H_Proxy_Authenticate },
        { H_Vary },
        { NULL },
        { H_WWW_Authenticate },
        { H_Warning },
        { H_Via },
        { NULL }, { NULL }, { NULL }, { NULL },
        { NULL }, { NULL }, { NULL }, { NULL },
        { NULL }, { NULL }, { NULL }, { NULL },
        { NULL }, { NULL }, { NULL },
        { H_Proxy_Authorization }
};

static struct http_hdrflg *
http_hdr_flags(const char *b, const char *e)
{
        unsigned u;
        struct http_hdrflg *retval;

        if (b == NULL || e == NULL)
                return (NULL);
        assert(b <= e);
        u = (unsigned)(e - b);
        assert(b + u == e);
        if (u < GPERF_MIN_WORD_LENGTH || u > GPERF_MAX_WORD_LENGTH)
                return (NULL);
        u += http_asso_values[(uint8_t)(e[-1])] +
             http_asso_values[(uint8_t)(b[0])];
        if (u > GPERF_MAX_HASH_VALUE)
                return (NULL);
        retval = &http_hdrflg[u];
        if (retval->hdr == NULL)
                return (NULL);
        if (!http_hdr_at(retval->hdr + 1, b, e - b))
                return (NULL);
        return (retval);
}

/*--------------------------------------------------------------------*/

static void
http_init_hdr(char *hdr, int flg)
{
        struct http_hdrflg *f;

        hdr[0] = strlen(hdr + 1);
        f = http_hdr_flags(hdr + 1, hdr + hdr[0]);
        AN(f);
        assert(f->hdr == hdr);
        f->flag = flg;
}

void
HTTP_Init(void)
{
        struct vsb *vsb;

#define HTTPH(a, b, c) http_init_hdr(b, c);
#include "tbl/http_headers.h"

        vsb = VSB_new_auto();
        AN(vsb);
        VSB_printf(vsb, "1.1 %s (Varnish/" PACKAGE_BRANCH ")",
            heritage.identity);
        AZ(VSB_finish(vsb));
        REPLACE(via_hdr, VSB_data(vsb));
        VSB_destroy(&vsb);
}

/*--------------------------------------------------------------------
 * These two functions are in an incestuous relationship with the
 * order of macros in include/tbl/vsl_tags_http.h
 *
 * The http->logtag is the SLT_*Method enum, and we add to that, to
 * get the SLT_ to use.
 */

static void
http_VSLH(const struct http *hp, unsigned hdr)
{
        int i;

        if (hp->vsl != NULL) {
                assert(VXID_TAG(hp->vsl->wid));
                i = hdr;
                if (i > HTTP_HDR_FIRST)
                        i = HTTP_HDR_FIRST;
                i += hp->logtag;
                VSLbt(hp->vsl, (enum VSL_tag_e)i, hp->hd[hdr]);
        }
}

static void
http_VSLH_del(const struct http *hp, unsigned hdr)
{
        int i;

        if (hp->vsl != NULL) {
                /* We don't support unsetting stuff in the first line */
                assert (hdr >= HTTP_HDR_FIRST);
                assert(VXID_TAG(hp->vsl->wid));
                i = (HTTP_HDR_UNSET - HTTP_HDR_METHOD);
                i += hp->logtag;
                VSLbt(hp->vsl, (enum VSL_tag_e)i, hp->hd[hdr]);
        }
}

/*--------------------------------------------------------------------*/

void
http_VSL_log(const struct http *hp)
{
        unsigned u;

        for (u = 0; u < hp->nhd; u++)
                if (hp->hd[u].b != NULL)
                        http_VSLH(hp, u);
}

/*--------------------------------------------------------------------*/

static void
http_fail(const struct http *hp)
{
        char id[WS_ID_SIZE];

        VSC_C_main->losthdr++;
        WS_Id(hp->ws, id);
        VSLb(hp->vsl, SLT_Error, "out of workspace (%s)", id);
        WS_MarkOverflow(hp->ws);
}

/*--------------------------------------------------------------------
 * List of canonical HTTP response code names from RFC2616
 */

static struct http_msg {
        unsigned        nbr;
        const char      *status;
        const char      *txt;
} http_msg[] = {
#define HTTP_RESP(n, t) { n, #n, t},
#include "tbl/http_response.h"
        { 0, "0", NULL }
};

const char *
http_Status2Reason(unsigned status, const char **sstr)
{
        struct http_msg *mp;

        status %= 1000;
        assert(status >= 100);
        for (mp = http_msg; mp->nbr != 0 && mp->nbr <= status; mp++)
                if (mp->nbr == status) {
                        if (sstr)
                                *sstr = mp->status;
                        return (mp->txt);
                }
        return ("Unknown HTTP Status");
}

/*--------------------------------------------------------------------*/

unsigned
HTTP_estimate(unsigned nhttp)
{

        /* XXX: We trust the structs to size-aligned as necessary */
        return (PRNDUP(sizeof(struct http) + sizeof(txt) * nhttp + nhttp));
}

struct http *
HTTP_create(void *p, uint16_t nhttp, unsigned len)
{
        struct http *hp;

        hp = p;
        hp->magic = HTTP_MAGIC;
        hp->hd = (void*)(hp + 1);
        hp->shd = nhttp;
        hp->hdf = (void*)(hp->hd + nhttp);
        assert((unsigned char*)p + len == hp->hdf + PRNDUP(nhttp));
        return (hp);
}

/*--------------------------------------------------------------------*/

void
HTTP_Setup(struct http *hp, struct ws *ws, struct vsl_log *vsl,
    enum VSL_tag_e  whence)
{
        http_Teardown(hp);
        hp->nhd = HTTP_HDR_FIRST;
        hp->logtag = whence;
        hp->ws = ws;
        hp->vsl = vsl;
}

/*--------------------------------------------------------------------
 * http_Teardown() is a safety feature, we use it to zap all http
 * structs once we're done with them, to minimize the risk that
 * old stale pointers exist to no longer valid stuff.
 */

void
http_Teardown(struct http *hp)
{

        CHECK_OBJ_NOTNULL(hp, HTTP_MAGIC);
        AN(hp->shd);
        memset(&hp->nhd, 0, sizeof *hp - offsetof(struct http, nhd));
        memset(hp->hd, 0, sizeof *hp->hd * hp->shd);
        memset(hp->hdf, 0, sizeof *hp->hdf * hp->shd);
}

/*--------------------------------------------------------------------
 * Duplicate the http content into another http
 * We cannot just memcpy the struct because the hd & hdf are private
 * storage to the struct http.
 */

void
HTTP_Dup(struct http *to, const struct http * fm)
{

        assert(fm->nhd <= to->shd);
        memcpy(to->hd, fm->hd, fm->nhd * sizeof *to->hd);
        memcpy(to->hdf, fm->hdf, fm->nhd * sizeof *to->hdf);
        to->nhd = fm->nhd;
        to->logtag = fm->logtag;
        to->status = fm->status;
        to->protover = fm->protover;
}


/*--------------------------------------------------------------------
 * Clone the entire http structure, including vsl & ws
 */

void
HTTP_Clone(struct http *to, const struct http * const fm)
{

        HTTP_Dup(to, fm);
        to->vsl = fm->vsl;
        to->ws = fm->ws;
}

/*--------------------------------------------------------------------*/

void
http_Proto(struct http *to)
{
        const char *fm;

        fm = to->hd[HTTP_HDR_PROTO].b;

        if (fm != NULL &&
            (fm[0] == 'H' || fm[0] == 'h') &&
            (fm[1] == 'T' || fm[1] == 't') &&
            (fm[2] == 'T' || fm[2] == 't') &&
            (fm[3] == 'P' || fm[3] == 'p') &&
            fm[4] == '/' &&
            vct_isdigit(fm[5]) &&
            fm[6] == '.' &&
            vct_isdigit(fm[7]) &&
            fm[8] == '\0') {
                to->protover = 10 * (fm[5] - '0') + (fm[7] - '0');
        } else {
                to->protover = 0;
        }
}

/*--------------------------------------------------------------------*/

void
http_SetH(struct http *to, unsigned n, const char *header)
{

        assert(n < to->nhd);
        AN(header);
        to->hd[n].b = TRUST_ME(header);
        to->hd[n].e = strchr(to->hd[n].b, '\0');
        to->hdf[n] = 0;
        http_VSLH(to, n);
        if (n == HTTP_HDR_PROTO)
                http_Proto(to);
}

/*--------------------------------------------------------------------*/

static void
http_PutField(struct http *to, int field, const char *string)
{
        const char *p;

        CHECK_OBJ_NOTNULL(to, HTTP_MAGIC);
        p = WS_Copy(to->ws, string, -1);
        if (p == NULL) {
                http_fail(to);
                VSLbs(to->vsl, SLT_LostHeader, TOSTRAND(string));
                return;
        }
        http_SetH(to, field, p);
}

/*--------------------------------------------------------------------*/

int
http_IsHdr(const txt *hh, hdr_t hdr)
{
        unsigned l;

        Tcheck(*hh);
        AN(hdr);
        l = hdr[0];
        assert(l == strlen(hdr + 1));
        assert(hdr[l] == ':');
        hdr++;
        return (http_hdr_at(hdr, hh->b, l));
}

/*--------------------------------------------------------------------*/

static unsigned
http_findhdr(const struct http *hp, unsigned l, const char *hdr)
{
        unsigned u;

        for (u = HTTP_HDR_FIRST; u < hp->nhd; u++) {
                Tcheck(hp->hd[u]);
                if (hp->hd[u].e < hp->hd[u].b + l + 1)
                        continue;
                if (hp->hd[u].b[l] != ':')
                        continue;
                if (!http_hdr_at(hdr, hp->hd[u].b, l))
                        continue;
                return (u);
        }
        return (0);
}

/*--------------------------------------------------------------------
 * Count how many instances we have of this header
 */

unsigned
http_CountHdr(const struct http *hp, hdr_t hdr)
{
        unsigned retval = 0;
        unsigned u;

        CHECK_OBJ_NOTNULL(hp, HTTP_MAGIC);

        for (u = HTTP_HDR_FIRST; u < hp->nhd; u++) {
                Tcheck(hp->hd[u]);
                if (http_IsHdr(&hp->hd[u], hdr))
                        retval++;
        }
        return (retval);
}

/*--------------------------------------------------------------------
 * This function collapses multiple header lines of the same name.
 * The lines are joined with a comma, according to [rfc2616, 4.2bot, p32]
 */

void
http_CollectHdr(struct http *hp, hdr_t hdr)
{

        http_CollectHdrSep(hp, hdr, NULL);
}

/*--------------------------------------------------------------------
 * You may prefer to collapse header fields using a different separator.
 * For Cookie headers, the separator is "; " for example. That's probably
 * the only example too.
 */

void
http_CollectHdrSep(struct http *hp, hdr_t hdr, const char *sep)
{
        unsigned u, l, lsep, ml, f, x, d;
        char *b = NULL, *e = NULL;
        const char *v;

        CHECK_OBJ_NOTNULL(hp, HTTP_MAGIC);
        if (WS_Overflowed(hp->ws))
                return;

        if (sep == NULL || *sep == '\0')
                sep = ", ";
        lsep = strlen(sep);

        l = hdr[0];
        assert(l == strlen(hdr + 1));
        assert(hdr[l] == ':');
        f = http_findhdr(hp, l - 1, hdr + 1);
        if (f == 0)
                return;

        for (d = u = f + 1; u < hp->nhd; u++) {
                Tcheck(hp->hd[u]);
                if (!http_IsHdr(&hp->hd[u], hdr)) {
                        if (d != u) {
                                hp->hd[d] = hp->hd[u];
                                hp->hdf[d] = hp->hdf[u];
                        }
                        d++;
                        continue;
                }
                if (b == NULL) {
                        /* Found second header, start our collection */
                        ml = WS_ReserveAll(hp->ws);
                        b = WS_Reservation(hp->ws);
                        e = b + ml;
                        x = Tlen(hp->hd[f]);
                        if (b + x >= e) {
                                http_fail(hp);
                                VSLbs(hp->vsl, SLT_LostHeader,
                                    TOSTRAND(hdr + 1));
                                WS_Release(hp->ws, 0);
                                return;
                        }
                        memcpy(b, hp->hd[f].b, x);
                        b += x;
                }

                AN(b);
                AN(e);

                /* Append the Nth header we found */
                x = Tlen(hp->hd[u]) - l;

                v = hp->hd[u].b + *hdr;
                while (vct_issp(*v)) {
                        v++;
                        x--;
                }

                if (b + lsep + x >= e) {
                        http_fail(hp);
                        VSLbs(hp->vsl, SLT_LostHeader, TOSTRAND(hdr + 1));
                        WS_Release(hp->ws, 0);
                        return;
                }
                memcpy(b, sep, lsep);
                b += lsep;
                memcpy(b, v, x);
                b += x;
        }
        if (b == NULL)
                return;
        hp->nhd = (uint16_t)d;
        AN(e);
        *b = '\0';
        hp->hd[f].b = WS_Reservation(hp->ws);
        hp->hd[f].e = b;
        WS_ReleaseP(hp->ws, b + 1);
}

/*--------------------------------------------------------------------*/

int
http_GetHdr(const struct http *hp, hdr_t hdr, const char **ptr)
{
        unsigned u, l;
        const char *p;

        l = hdr[0];
        assert(l == strlen(hdr + 1));
        assert(hdr[l] == ':');
        hdr++;
        u = http_findhdr(hp, l - 1, hdr);
        if (u == 0) {
                if (ptr != NULL)
                        *ptr = NULL;
                return (0);
        }
        if (ptr != NULL) {
                p = hp->hd[u].b + l;
                while (vct_issp(*p))
                        p++;
                *ptr = p;
        }
        return (1);
}

/*-----------------------------------------------------------------------------
 * Split source string at any of the separators, return pointer to first
 * and last+1 char of substrings, with whitespace trimmed at both ends.
 * If sep being an empty string is shorthand for VCT::SP
 * If stop is NULL, src is NUL terminated.
 */

static int
http_split(const char **src, const char *stop, const char *sep,
    const char **b, const char **e)
{
        const char *p, *q;

        AN(src);
        AN(*src);
        AN(sep);
        AN(b);
        AN(e);

        if (stop == NULL)
                stop = strchr(*src, '\0');

        for (p = *src; p < stop && (vct_issp(*p) || strchr(sep, *p)); p++)
                continue;

        if (p >= stop) {
                *b = NULL;
                *e = NULL;
                return (0);
        }

        *b = p;
        if (*sep == '\0') {
                for (q = p + 1; q < stop && !vct_issp(*q); q++)
                        continue;
                *e = q;
                *src = q;
                return (1);
        }
        for (q = p + 1; q < stop && !strchr(sep, *q); q++)
                continue;
        *src = q;
        while (q > p && vct_issp(q[-1]))
                q--;
        *e = q;
        return (1);
}

/*-----------------------------------------------------------------------------
 * Comparison rule for tokens:
 *      if target string starts with '"', we use memcmp() and expect closing
 *      double quote as well
 *      otherwise we use http_tok_at()
 *
 * On match we increment *bp past the token name.
 */

static int
http_istoken(const char **bp, const char *e, const char *token)
{
        int fl = strlen(token);
        const char *b;

        AN(bp);
        AN(e);
        AN(token);

        b = *bp;

        if (b + fl + 2 <= e && *b == '"' &&
            !memcmp(b + 1, token, fl) && b[fl + 1] == '"') {
                *bp += fl + 2;
                return (1);
        }
        if (b + fl <= e && http_tok_at(b, token, fl) &&
            (b + fl == e || !vct_istchar(b[fl]))) {
                *bp += fl;
                return (1);
        }
        return (0);
}

/*-----------------------------------------------------------------------------
 * Find a given data element (token) in a header according to RFC2616's #rule
 * (section 2.1, p15)
 *
 * On case sensitivity:
 *
 * Section 4.2 (Messages Headers) defines field (header) name as case
 * insensitive, but the field (header) value/content may be case-sensitive.
 *
 * http_GetHdrToken looks up a token in a header value and the rfc does not say
 * explicitly if tokens are to be compared with or without respect to case.
 *
 * But all examples and specific statements regarding tokens follow the rule
 * that unquoted tokens are to be matched case-insensitively and quoted tokens
 * case-sensitively.
 *
 * The optional pb and pe arguments will point to the token content start and
 * end+1, white space trimmed on both sides.
 */

int
http_GetHdrToken(const struct http *hp, hdr_t hdr,
    const char *token, const char **pb, const char **pe)
{
        const char *h, *b, *e;

        if (pb != NULL)
                *pb = NULL;
        if (pe != NULL)
                *pe = NULL;
        if (!http_GetHdr(hp, hdr, &h))
                return (0);
        AN(h);

        while (http_split(&h, NULL, ",", &b, &e))
                if (http_istoken(&b, e, token))
                        break;
        if (b == NULL)
                return (0);
        if (pb != NULL) {
                for (; vct_islws(*b); b++)
                        continue;
                if (b == e) {
                        b = NULL;
                        e = NULL;
                }
                *pb = b;
                if (pe != NULL)
                        *pe = e;
        }
        return (1);
}

/*--------------------------------------------------------------------
 * Find a given header field's quality value (qvalue).
 */

double
http_GetHdrQ(const struct http *hp, hdr_t hdr, const char *field)
{
        const char *hb, *he, *b, *e;
        int i;
        double a, f;

        i = http_GetHdrToken(hp, hdr, field, &hb, &he);
        if (!i)
                return (0.);

        if (hb == NULL)
                return (1.);
        while (http_split(&hb, he, ";", &b, &e)) {
                if (*b != 'q')
                        continue;
                for (b++; b < e && vct_issp(*b); b++)
                        continue;
                if (b == e || *b != '=')
                        continue;
                break;
        }
        if (b == NULL)
                return (1.);
        for (b++; b < e && vct_issp(*b); b++)
                continue;
        if (b == e || (*b != '.' && !vct_isdigit(*b)))
                return (0.);
        a = 0;
        while (b < e && vct_isdigit(*b)) {
                a *= 10.;
                a += *b - '0';
                b++;
        }
        if (b == e || *b++ != '.')
                return (a);
        f = .1;
        while (b < e && vct_isdigit(*b)) {
                a += f * (*b - '0');
                f *= .1;
                b++;
        }
        return (a);
}

/*--------------------------------------------------------------------
 * Find a given header field's value.
 */

int
http_GetHdrField(const struct http *hp, hdr_t hdr,
    const char *field, const char **ptr)
{
        const char *h;
        int i;

        if (ptr != NULL)
                *ptr = NULL;

        h = NULL;
        i = http_GetHdrToken(hp, hdr, field, &h, NULL);
        if (!i)
                return (i);

        if (ptr != NULL && h != NULL) {
                /* Skip whitespace, looking for '=' */
                while (*h && vct_issp(*h))
                        h++;
                if (*h == '=') {
                        h++;
                        while (*h && vct_issp(*h))
                                h++;
                        *ptr = h;
                }
        }
        return (i);
}

/*--------------------------------------------------------------------*/

ssize_t
http_GetContentLength(const struct http *hp)
{
        ssize_t cl;
        const char *b;

        CHECK_OBJ_NOTNULL(hp, HTTP_MAGIC);

        if (!http_GetHdr(hp, H_Content_Length, &b))
                return (-1);
        cl = VNUM_uint(b, NULL, &b);
        if (cl < 0)
                return (-2);
        while (vct_islws(*b))
                b++;
        if (*b != '\0')
                return (-2);
        return (cl);
}

ssize_t
http_GetContentRange(const struct http *hp, ssize_t *lo, ssize_t *hi)
{
        ssize_t tmp, cl;
        const char *b, *t;

        CHECK_OBJ_NOTNULL(hp, HTTP_MAGIC);

        if (lo == NULL)
                lo = &tmp;
        if (hi == NULL)
                hi = &tmp;

        *lo = *hi = -1;

        if (!http_GetHdr(hp, H_Content_Range, &b))
                return (-1);

        t = strchr(b, ' ');
        if (t == NULL)
                return (-2);            // Missing space after range unit

        if (!http_range_at(b, bytes, t - b))
                return (-1);            // Unknown range unit, ignore
        b = t + 1;

        if (*b == '*') {                // Content-Range: bytes */123
                *lo = *hi = -1;
                b++;
        } else {                        // Content-Range: bytes 1-2/3
                *lo = VNUM_uint(b, NULL, &b);
                if (*lo < 0)
                        return (-2);
                if (*b != '-')
                        return (-2);
                *hi = VNUM_uint(b + 1, NULL, &b);
                if (*hi < 0)
                        return (-2);
        }
        if (*b != '/')
                return (-2);
        if (b[1] == '*') {              // Content-Range: bytes 1-2/*
                cl = -1;
                b += 2;
        } else {
                cl = VNUM_uint(b + 1, NULL, &b);
                if (cl <= 0)
                        return (-2);
        }
        while (vct_islws(*b))
                b++;
        if (*b != '\0')
                return (-2);
        if (*lo > *hi)
                return (-2);
        assert(cl >= -1);
        if (*lo >= cl || *hi >= cl)
                return (-2);
        AN(cl);
        return (cl);
}

const char *
http_GetRange(const struct http *hp, ssize_t *lo, ssize_t *hi, ssize_t len)
{
        ssize_t tmp_lo, tmp_hi;
        const char *b, *t;

        CHECK_OBJ_NOTNULL(hp, HTTP_MAGIC);

        if (lo == NULL)
                lo = &tmp_lo;
        if (hi == NULL)
                hi = &tmp_hi;

        *lo = *hi = -1;

        if (!http_GetHdr(hp, H_Range, &b))
                return (NULL);

        t = strchr(b, '=');
        if (t == NULL)
                return ("Missing '='");

        if (!http_range_at(b, bytes, t - b))
                return ("Not Bytes");
        b = t + 1;

        *lo = VNUM_uint(b, NULL, &b);
        if (*lo == -2)
                return ("Low number too big");
        if (*b++ != '-')
                return ("Missing hyphen");

        *hi = VNUM_uint(b, NULL, &b);
        if (*hi == -2)
                return ("High number too big");
        if (*lo == -1 && *hi == -1)
                return ("Neither high nor low");
        if (*lo == -1 && *hi == 0)
                return ("No low, high is zero");
        if (*hi >= 0 && *hi < *lo)
                return ("high smaller than low");

        while (vct_islws(*b))
                b++;
        if (*b != '\0')
                return ("Trailing stuff");

        assert(*lo >= -1);
        assert(*hi >= -1);

        if (len <= 0)
                return (NULL);                  // Allow 200 response

        if (*lo < 0) {
                assert(*hi > 0);
                *lo = len - *hi;
                if (*lo < 0)
                        *lo = 0;
                *hi = len - 1;
        } else if (len >= 0 && (*hi >= len || *hi < 0)) {
                *hi = len - 1;
        }

        if (*lo >= len)
                return ("low range beyond object");

        return (NULL);
}

/*--------------------------------------------------------------------
 */

stream_close_t
http_DoConnection(struct http *hp, stream_close_t sc_close)
{
        const char *h, *b, *e;
        stream_close_t retval;
        unsigned u, v;
        struct http_hdrflg *f;

        CHECK_OBJ_NOTNULL(hp, HTTP_MAGIC);
        assert(sc_close == SC_REQ_CLOSE || sc_close == SC_RESP_CLOSE);

        if (hp->protover == 10)
                retval = SC_REQ_HTTP10;
        else
                retval = SC_NULL;

        http_CollectHdr(hp, H_Connection);
        if (!http_GetHdr(hp, H_Connection, &h))
                return (retval);
        AN(h);
        while (http_split(&h, NULL, ",", &b, &e)) {
                u = pdiff(b, e);
                if (u == 5 && http_hdr_at(b, "close", u))
                        retval = sc_close;
                if (u == 10 && http_hdr_at(b, "keep-alive", u))
                        retval = SC_NULL;

                /* Refuse removal of well-known-headers if they would pass. */
                f = http_hdr_flags(b, e);
                if (f != NULL && !(f->flag & HTTPH_R_PASS))
                        return (SC_RX_BAD);

                for (v = HTTP_HDR_FIRST; v < hp->nhd; v++) {
                        Tcheck(hp->hd[v]);
                        if (hp->hd[v].e < hp->hd[v].b + u + 1)
                                continue;
                        if (hp->hd[v].b[u] != ':')
                                continue;
                        if (!http_hdr_at(b, hp->hd[v].b, u))
                                continue;
                        hp->hdf[v] |= HDF_FILTER;
                }
        }
        CHECK_OBJ_NOTNULL(retval, STREAM_CLOSE_MAGIC);
        return (retval);
}

/*--------------------------------------------------------------------*/

int
http_HdrIs(const struct http *hp, hdr_t hdr, const char *val)
{
        const char *p;

        if (!http_GetHdr(hp, hdr, &p))
                return (0);
        AN(p);
        if (http_tok_eq(p, val))
                return (1);
        return (0);
}

/*--------------------------------------------------------------------*/

uint16_t
http_GetStatus(const struct http *hp)
{

        CHECK_OBJ_NOTNULL(hp, HTTP_MAGIC);
        return (hp->status);
}

int
http_IsStatus(const struct http *hp, int val)
{

        CHECK_OBJ_NOTNULL(hp, HTTP_MAGIC);
        assert(val >= 100 && val <= 999);
        return (val == (hp->status % 1000));
}

/*--------------------------------------------------------------------
 * Setting the status will also set the Reason appropriately
 */

void
http_SetStatus(struct http *to, uint16_t status, const char *reason)
{
        char buf[4];
        const char *sstr = NULL;

        CHECK_OBJ_NOTNULL(to, HTTP_MAGIC);
        /*
         * We allow people to use top digits for internal VCL
         * signalling, but strip them from the ASCII version.
         */
        to->status = status;
        status %= 1000;
        assert(status >= 100);

        if (reason == NULL)
                reason = http_Status2Reason(status, &sstr);
        else
                (void)http_Status2Reason(status, &sstr);

        if (sstr) {
                http_SetH(to, HTTP_HDR_STATUS, sstr);
        } else {
                bprintf(buf, "%03d", status);
                http_PutField(to, HTTP_HDR_STATUS, buf);
        }
        http_SetH(to, HTTP_HDR_REASON, reason);
}

/*--------------------------------------------------------------------*/

const char *
http_GetMethod(const struct http *hp)
{

        CHECK_OBJ_NOTNULL(hp, HTTP_MAGIC);
        Tcheck(hp->hd[HTTP_HDR_METHOD]);
        return (hp->hd[HTTP_HDR_METHOD].b);
}

/*--------------------------------------------------------------------
 * Force a particular header field to a particular value
 */

void
http_ForceField(struct http *to, unsigned n, const char *t)
{
        int i;

        CHECK_OBJ_NOTNULL(to, HTTP_MAGIC);
        assert(n < HTTP_HDR_FIRST);
        assert(n == HTTP_HDR_METHOD || n == HTTP_HDR_PROTO);
        AN(t);

        /* NB: method names and protocol versions are case-sensitive. */
        if (to->hd[n].b == NULL || strcmp(to->hd[n].b, t)) {
                i = (HTTP_HDR_UNSET - HTTP_HDR_METHOD);
                i += to->logtag;
                /* XXX: this is a dead branch */
                if (n >= HTTP_HDR_FIRST)
                        VSLbt(to->vsl, (enum VSL_tag_e)i, to->hd[n]);
                http_SetH(to, n, t);
        }
}

/*--------------------------------------------------------------------*/

void
http_PutResponse(struct http *to, const char *proto, uint16_t status,
    const char *reason)
{

        CHECK_OBJ_NOTNULL(to, HTTP_MAGIC);
        if (proto != NULL)
                http_SetH(to, HTTP_HDR_PROTO, proto);
        http_SetStatus(to, status, reason);
}

/*--------------------------------------------------------------------
 * check if header is filtered by the dynamic marker or the static
 * definitions in http_headers.h
 */

static inline int
http_isfiltered(const struct http *fm, unsigned u, unsigned how)
{
        const char *e;
        const struct http_hdrflg *f;

        if (fm->hdf[u] & HDF_FILTER)
                return (1);
        if (u < HTTP_HDR_FIRST)
                return (0);
        e = strchr(fm->hd[u].b, ':');
        if (e == NULL)
                return (0);
        f = http_hdr_flags(fm->hd[u].b, e);
        return (f != NULL && f->flag & how);
}

int
http_IsFiltered(const struct http *fm, unsigned u, unsigned how)
{

        return (http_isfiltered(fm, u, how));
}

/*--------------------------------------------------------------------
 * Estimate how much workspace we need to Filter this header according
 * to 'how'.
 */

unsigned
http_EstimateWS(const struct http *fm, unsigned how)
{
        unsigned u, l;

        l = 4;
        CHECK_OBJ_NOTNULL(fm, HTTP_MAGIC);
        for (u = 0; u < fm->nhd; u++) {
                if (u == HTTP_HDR_METHOD || u == HTTP_HDR_URL)
                        continue;
                Tcheck(fm->hd[u]);
                if (http_isfiltered(fm, u, how))
                        continue;
                l += Tlen(fm->hd[u]) + 1L;
        }
        return (PRNDUP(l + 1L));
}

/*--------------------------------------------------------------------
 * Encode http struct as byte string.
 *
 * XXX: We could save considerable special-casing below by encoding also
 * XXX: H__Status, H__Reason and H__Proto into the string, but it would
 * XXX: add 26-30 bytes to all encoded objects to save a little code.
 * XXX: It could possibly be a good idea for later HTTP versions.
 */

void
HTTP_Encode(const struct http *fm, uint8_t *p0, unsigned l, unsigned how)
{
        unsigned u, w;
        uint16_t n;
        uint8_t *p, *e;

        AN(p0);
        AN(l);
        p = p0;
        e = p + l;
        assert(p + 5 <= e);
        assert(fm->nhd <= fm->shd);
        n = HTTP_HDR_FIRST - 3;
        vbe16enc(p + 2, fm->status);
        p += 4;
        CHECK_OBJ_NOTNULL(fm, HTTP_MAGIC);
        for (u = 0; u < fm->nhd; u++) {
                if (u == HTTP_HDR_METHOD || u == HTTP_HDR_URL)
                        continue;
                Tcheck(fm->hd[u]);
                if (http_isfiltered(fm, u, how))
                        continue;
                http_VSLH(fm, u);
                w = Tlen(fm->hd[u]) + 1L;
                assert(p + w + 1 <= e);
                memcpy(p, fm->hd[u].b, w);
                p += w;
                n++;
        }
        *p++ = '\0';
        assert(p <= e);
        vbe16enc(p0, n + 1);
}

/*--------------------------------------------------------------------
 * Decode byte string into http struct
 */

int
HTTP_Decode(struct http *to, const uint8_t *fm)
{

        CHECK_OBJ_NOTNULL(to, HTTP_MAGIC);
        AN(to->vsl);
        AN(fm);
        if (vbe16dec(fm) <= to->shd) {
                to->status = vbe16dec(fm + 2);
                fm += 4;
                for (to->nhd = 0; to->nhd < to->shd; to->nhd++) {
                        if (to->nhd == HTTP_HDR_METHOD ||
                            to->nhd == HTTP_HDR_URL) {
                                to->hd[to->nhd].b = NULL;
                                to->hd[to->nhd].e = NULL;
                                continue;
                        }
                        if (*fm == '\0')
                                return (0);
                        to->hd[to->nhd].b = (const void*)fm;
                        fm = (const void*)strchr((const void*)fm, '\0');
                        to->hd[to->nhd].e = (const void*)fm;
                        fm++;
                        http_VSLH(to, to->nhd);
                }
        }
        VSLb(to->vsl, SLT_Error,
            "Too many headers to Decode object (%u vs. %u)",
            vbe16dec(fm), to->shd);
        return (-1);
}

/*--------------------------------------------------------------------*/

uint16_t
HTTP_GetStatusPack(struct worker *wrk, struct objcore *oc)
{
        const char *ptr;
        ptr = ObjGetAttr(wrk, oc, OA_HEADERS, NULL);
        AN(ptr);

        return (vbe16dec(ptr + 2));
}

/*--------------------------------------------------------------------*/

/* Get the first packed header */
int
HTTP_IterHdrPack(struct worker *wrk, struct objcore *oc, const char **p)
{
        const char *ptr;

        CHECK_OBJ_NOTNULL(wrk, WORKER_MAGIC);
        CHECK_OBJ_NOTNULL(oc, OBJCORE_MAGIC);
        AN(p);

        if (*p == NULL) {
                ptr = ObjGetAttr(wrk, oc, OA_HEADERS, NULL);
                AN(ptr);
                ptr += 4;       /* Skip nhd and status */
                ptr = strchr(ptr, '\0') + 1;    /* Skip :proto: */
                ptr = strchr(ptr, '\0') + 1;    /* Skip :status: */
                ptr = strchr(ptr, '\0') + 1;    /* Skip :reason: */
                *p = ptr;
        } else {
                *p = strchr(*p, '\0') + 1;      /* Skip to next header */
        }
        if (**p == '\0')
                return (0);
        return (1);
}

const char *
HTTP_GetHdrPack(struct worker *wrk, struct objcore *oc, hdr_t hdr)
{
        const char *ptr;
        unsigned l;

        CHECK_OBJ_NOTNULL(wrk, WORKER_MAGIC);
        CHECK_OBJ_NOTNULL(oc, OBJCORE_MAGIC);
        AN(hdr);

        l = hdr[0];
        assert(l > 0);
        assert(l == strlen(hdr + 1));
        assert(hdr[l] == ':');
        hdr++;

        if (hdr[0] == ':') {
                /* Special cases */
                ptr = ObjGetAttr(wrk, oc, OA_HEADERS, NULL);
                AN(ptr);
                ptr += 4;       /* Skip nhd and status */

                /* XXX: should we also have h2_hdr_eq() ? */
                if (!strcmp(hdr, ":proto:"))
                        return (ptr);
                ptr = strchr(ptr, '\0') + 1;
                if (!strcmp(hdr, ":status:"))
                        return (ptr);
                ptr = strchr(ptr, '\0') + 1;
                if (!strcmp(hdr, ":reason:"))
                        return (ptr);
                WRONG("Unknown magic packed header");
        }

        HTTP_FOREACH_PACK(wrk, oc, ptr) {
                if (http_hdr_at(ptr, hdr, l)) {
                        ptr += l;
                        while (vct_islws(*ptr))
                                ptr++;
                        return (ptr);
                }
        }

        return (NULL);
}

/*--------------------------------------------------------------------
 * Merge any headers in the oc->OA_HEADER into the struct http if they
 * are not there already.
 */

void
HTTP_Merge(struct worker *wrk, struct objcore *oc, struct http *to)
{
        const char *ptr;
        unsigned u;
        const char *p;
        unsigned nhd_before_merge;

        CHECK_OBJ_NOTNULL(wrk, WORKER_MAGIC);
        CHECK_OBJ_NOTNULL(oc, OBJCORE_MAGIC);
        CHECK_OBJ_NOTNULL(to, HTTP_MAGIC);

        ptr = ObjGetAttr(wrk, oc, OA_HEADERS, NULL);
        AN(ptr);

        to->status = vbe16dec(ptr + 2);
        ptr += 4;

        for (u = 0; u < HTTP_HDR_FIRST; u++) {
                if (u == HTTP_HDR_METHOD || u == HTTP_HDR_URL)
                        continue;
                http_SetH(to, u, ptr);
                ptr = strchr(ptr, '\0') + 1;
        }
        nhd_before_merge = to->nhd;
        while (*ptr != '\0') {
                p = strchr(ptr, ':');
                AN(p);
                u = http_findhdr(to, p - ptr, ptr);
                if (u == 0 || u >= nhd_before_merge)
                        http_SetHeader(to, ptr);
                ptr = strchr(ptr, '\0') + 1;
        }
}

/*--------------------------------------------------------------------*/

static void
http_linkh(const struct http *to, const struct http *fm, unsigned n)
{

        assert(n < HTTP_HDR_FIRST);
        Tcheck(fm->hd[n]);
        to->hd[n] = fm->hd[n];
        to->hdf[n] = fm->hdf[n];
        http_VSLH(to, n);
}

/*--------------------------------------------------------------------*/

void
http_FilterReq(struct http *to, const struct http *fm, unsigned how)
{
        unsigned u;

        CHECK_OBJ_NOTNULL(to, HTTP_MAGIC);
        CHECK_OBJ_NOTNULL(fm, HTTP_MAGIC);

        http_linkh(to, fm, HTTP_HDR_METHOD);
        http_linkh(to, fm, HTTP_HDR_URL);
        http_linkh(to, fm, HTTP_HDR_PROTO);
        to->protover = fm->protover;
        to->status = fm->status;

        to->nhd = HTTP_HDR_FIRST;
        for (u = HTTP_HDR_FIRST; u < fm->nhd; u++) {
                Tcheck(fm->hd[u]);
                if (http_isfiltered(fm, u, how))
                        continue;
                assert (to->nhd < to->shd);
                to->hd[to->nhd] = fm->hd[u];
                to->hdf[to->nhd] = 0;
                http_VSLH(to, to->nhd);
                to->nhd++;
        }
}

/*--------------------------------------------------------------------
 * This function copies any header fields which reference foreign
 * storage into our own WS.
 */

void
http_CopyHome(const struct http *hp)
{
        unsigned u, l;
        const char *p;

        for (u = 0; u < hp->nhd; u++) {
                if (hp->hd[u].b == NULL) {
                        assert(u < HTTP_HDR_FIRST);
                        continue;
                }

                l = Tlen(hp->hd[u]);
                if (WS_Allocated(hp->ws, hp->hd[u].b, l))
                        continue;

                p = WS_Copy(hp->ws, hp->hd[u].b, l + 1L);
                if (p == NULL) {
                        http_fail(hp);
                        VSLbs(hp->vsl, SLT_LostHeader, TOSTRAND(hp->hd[u].b));
                        return;
                }
                hp->hd[u].b = p;
                hp->hd[u].e = p + l;
        }
}

/*--------------------------------------------------------------------*/

void
http_SetHeader(struct http *to, const char *header)
{

        CHECK_OBJ_NOTNULL(to, HTTP_MAGIC);
        if (to->nhd >= to->shd) {
                VSLbs(to->vsl, SLT_LostHeader, TOSTRAND(header));
                http_fail(to);
                return;
        }
        http_SetH(to, to->nhd++, header);
}

/*--------------------------------------------------------------------*/

void
http_ForceHeader(struct http *to, hdr_t hdr, const char *val)
{

        CHECK_OBJ_NOTNULL(to, HTTP_MAGIC);
        if (http_HdrIs(to, hdr, val))
                return;
        http_Unset(to, hdr);
        http_PrintfHeader(to, "%s %s", hdr + 1, val);
}

void
http_AppendHeader(struct http *to, hdr_t hdr, const char *val)
{
        const char *old;

        http_CollectHdr(to, hdr);
        if (http_GetHdr(to, hdr, &old)) {
                http_Unset(to, hdr);
                http_PrintfHeader(to, "%s %s, %s", hdr + 1, old, val);
        } else {
                http_PrintfHeader(to, "%s %s", hdr + 1, val);
        }
}

void
http_PrintfHeader(struct http *to, const char *fmt, ...)
{
        va_list ap, ap2;
        struct vsb vsb[1];
        size_t sz;
        char *p;

        CHECK_OBJ_NOTNULL(to, HTTP_MAGIC);

        va_start(ap, fmt);
        va_copy(ap2, ap);

        WS_VSB_new(vsb, to->ws);
        VSB_vprintf(vsb, fmt, ap);
        p = WS_VSB_finish(vsb, to->ws, &sz);

        if (p == NULL || to->nhd >= to->shd) {
                http_fail(to);
                VSLbv(to->vsl, SLT_LostHeader, fmt, ap2);
        } else {
                http_SetH(to, to->nhd++, p);
        }
        va_end(ap);
        va_end(ap2);
}

void
http_TimeHeader(struct http *to, const char *fmt, vtim_real now)
{
        char *p;

        CHECK_OBJ_NOTNULL(to, HTTP_MAGIC);
        if (to->nhd >= to->shd) {
                VSLbs(to->vsl, SLT_LostHeader, TOSTRAND(fmt));
                http_fail(to);
                return;
        }
        p = WS_Alloc(to->ws, strlen(fmt) + VTIM_FORMAT_SIZE);
        if (p == NULL) {
                http_fail(to);
                VSLbs(to->vsl, SLT_LostHeader, TOSTRAND(fmt));
                return;
        }
        strcpy(p, fmt);
        VTIM_format(now, strchr(p, '\0'));
        http_SetH(to, to->nhd++, p);
}

const char *
http_ViaHeader(void)
{

        return (via_hdr);
}

/*--------------------------------------------------------------------*/

void
http_Unset(struct http *hp, hdr_t hdr)
{
        uint16_t u, v;

        for (v = u = HTTP_HDR_FIRST; u < hp->nhd; u++) {
                Tcheck(hp->hd[u]);
                if (http_IsHdr(&hp->hd[u], hdr)) {
                        http_VSLH_del(hp, u);
                        continue;
                }
                if (v != u) {
                        memcpy(&hp->hd[v], &hp->hd[u], sizeof *hp->hd);
                        memcpy(&hp->hdf[v], &hp->hdf[u], sizeof *hp->hdf);
                }
                v++;
        }
        hp->nhd = v;
}

		varnish-cache/bin/varnishd/cache/cache_http.c
0		/*-
1		* Copyright (c) 2006 Verdens Gang AS
2		* Copyright (c) 2006-2017 Varnish Software AS
3		* All rights reserved.
4		*
5		* Author: Poul-Henning Kamp <phk@phk.freebsd.dk>
6		*
7		* SPDX-License-Identifier: BSD-2-Clause
8		*
9		* Redistribution and use in source and binary forms, with or without
10		* modification, are permitted provided that the following conditions
11		* are met:
12		* 1. Redistributions of source code must retain the above copyright
13		* notice, this list of conditions and the following disclaimer.
14		* 2. Redistributions in binary form must reproduce the above copyright
15		* notice, this list of conditions and the following disclaimer in the
16		* documentation and/or other materials provided with the distribution.
17		*
18		* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19		* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20		* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21		* ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
22		* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23		* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24		* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25		* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26		* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27		* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28		* SUCH DAMAGE.
29		*
30		* HTTP request storage and manipulation
31		*/
32
33		#include "config.h"
34
35		#include "cache_varnishd.h"
36		#include <stdio.h>
37		#include <stdlib.h>
38
39		#include "common/heritage.h"
40
41		#include "vct.h"
42		#include "vend.h"
43		#include "vnum.h"
44		#include "vtim.h"
45
46		#define BODYSTATUS(U, l, n, a, k) \
47		const struct body_status BS_##U[1] = {{ \
48		.name = #l, \
49		.nbr = n, \
50		.avail = a, \
51		.length_known = k \
52		}};
53		#include "tbl/body_status.h"
54
55
56		#define HTTPH(a, b, c) char b[] = "*" a ":";
57		#include "tbl/http_headers.h"
58
59		const char H__Status[] = "\010:status:";
60		const char H__Proto[] = "\007:proto:";
61		const char H__Reason[] = "\010:reason:";
62
63		static char * via_hdr;
64
65		/*--------------------------------------------------------------------
66		* Perfect hash to rapidly recognize headers from tbl/http_headers.h
67		* which have non-zero flags.
68		*
69		* A suitable algorithm can be found with `gperf`:
70		*
71		* tr '" ,' ' ' < include/tbl/http_headers.h \|
72		* awk '$1 == "H(" {print $2}' \|
73		* gperf --ignore-case
74		*
75		*/
76
77		#define GPERF_MIN_WORD_LENGTH 2
78		#define GPERF_MAX_WORD_LENGTH 19
79		#define GPERF_MAX_HASH_VALUE 79
80
81		static const unsigned char http_asso_values[256] = {
82		80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
83		80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
84		80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
85		80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
86		80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
87		80, 80, 80, 0, 80, 80, 80, 80, 80, 80,
88		80, 80, 80, 80, 80, 5, 80, 20, 0, 0,
89		5, 10, 5, 5, 80, 0, 15, 0, 20, 80,
90		40, 80, 0, 35, 10, 20, 55, 45, 0, 0,
91		80, 80, 80, 80, 80, 80, 80, 5, 80, 20,
92		0, 0, 5, 10, 5, 5, 80, 0, 15, 0,
93		20, 80, 40, 80, 0, 35, 10, 20, 55, 45,
94		0, 0, 80, 80, 80, 80, 80, 80, 80, 80,
95		80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
96		80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
97		80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
98		80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
99		80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
100		80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
101		80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
102		80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
103		80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
104		80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
105		80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
106		80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
107		80, 80, 80, 80, 80, 80
108		};
109
110		static struct http_hdrflg {
111		char *hdr;
112		unsigned flag;
113		} http_hdrflg[GPERF_MAX_HASH_VALUE + 1] = {
114		{ NULL }, { NULL }, { NULL }, { NULL },
115		{ H_Date },
116		{ H_Range },
117		{ NULL },
118		{ H_Referer },
119		{ H_Age },
120		{ H_From },
121		{ H_Keep_Alive },
122		{ H_Retry_After },
123		{ H_TE },
124		{ H_If_Range },
125		{ H_ETag },
126		{ H_X_Forwarded_For },
127		{ H_Expect },
128		{ H_Trailer },
129		{ H_If_Match },
130		{ H_Host },
131		{ H_Accept_Language },
132		{ H_Accept },
133		{ H_If_Modified_Since },
134		{ H_If_None_Match },
135		{ H_If_Unmodified_Since },
136		{ NULL },
137		{ H_Cookie },
138		{ H_Upgrade },
139		{ H_Last_Modified },
140		{ H_Accept_Charset },
141		{ H_Accept_Encoding },
142		{ H_Content_MD5 },
143		{ H_Content_Type },
144		{ H_Content_Range },
145		{ NULL }, { NULL },
146		{ H_Content_Language },
147		{ H_Transfer_Encoding },
148		{ H_Authorization },
149		{ H_Content_Length },
150		{ H_User_Agent },
151		{ H_Server },
152		{ H_Expires },
153		{ H_Location },
154		{ NULL },
155		{ H_Set_Cookie },
156		{ H_Content_Encoding },
157		{ H_Max_Forwards },
158		{ H_Cache_Control },
159		{ NULL },
160		{ H_Connection },
161		{ H_Pragma },
162		{ NULL },
163		{ H_Accept_Ranges },
164		{ H_HTTP2_Settings },
165		{ H_Allow },
166		{ H_Content_Location },
167		{ NULL },
168		{ H_Proxy_Authenticate },
169		{ H_Vary },
170		{ NULL },
171		{ H_WWW_Authenticate },
172		{ H_Warning },
173		{ H_Via },
174		{ NULL }, { NULL }, { NULL }, { NULL },
175		{ NULL }, { NULL }, { NULL }, { NULL },
176		{ NULL }, { NULL }, { NULL }, { NULL },
177		{ NULL }, { NULL }, { NULL },
178		{ H_Proxy_Authorization }
179		};
180
181		static struct http_hdrflg *
182	2937047	http_hdr_flags(const char b, const char e)
183		{
184		unsigned u;
185		struct http_hdrflg *retval;
186
187	2937047	if (b == NULL \|\| e == NULL)
188	286	return (NULL);
189	2937015	assert(b <= e);
190	2937015	u = (unsigned)(e - b);
191	2937015	assert(b + u == e);
192	2937015	if (u < GPERF_MIN_WORD_LENGTH \|\| u > GPERF_MAX_WORD_LENGTH)
193	1162	return (NULL);
194	5871706	u += http_asso_values[(uint8_t)(e[-1])] +
195	2935853	http_asso_values[(uint8_t)(b[0])];
196	2935853	if (u > GPERF_MAX_HASH_VALUE)
197	39880	return (NULL);
198	2895973	retval = &http_hdrflg[u];
199	2895973	if (retval->hdr == NULL)
200	10105	return (NULL);
201	2885868	if (!http_hdr_at(retval->hdr + 1, b, e - b))
202	36240	return (NULL);
203	2849628	return (retval);
204	2937013	}
205
206		/--------------------------------------------------------------------/
207
208		static void
209	1907152	http_init_hdr(char *hdr, int flg)
210		{
211		struct http_hdrflg *f;
212
213	1907152	hdr[0] = strlen(hdr + 1);
214	1907152	f = http_hdr_flags(hdr + 1, hdr + hdr[0]);
215	1907152	AN(f);
216	1907152	assert(f->hdr == hdr);
217	1907152	f->flag = flg;
218	1907152	}
219
220		void
221	36676	HTTP_Init(void)
222		{
223		struct vsb *vsb;
224
225		#define HTTPH(a, b, c) http_init_hdr(b, c);
226		#include "tbl/http_headers.h"
227
228		vsb = VSB_new_auto();
229	36676	AN(vsb);
230		VSB_printf(vsb, "1.1 %s (Varnish/" PACKAGE_BRANCH ")",
231		heritage.identity);
232	36676	AZ(VSB_finish(vsb));
233	36676	REPLACE(via_hdr, VSB_data(vsb));
234		VSB_destroy(&vsb);
235		}
236
237		/*--------------------------------------------------------------------
238		* These two functions are in an incestuous relationship with the
239		* order of macros in include/tbl/vsl_tags_http.h
240		*
241		* The http->logtag is the SLT_*Method enum, and we add to that, to
242		* get the SLT_ to use.
243		*/
244
245		static void
246	4842024	http_VSLH(const struct http *hp, unsigned hdr)
247		{
248		int i;
249
250	4842024	if (hp->vsl != NULL) {
251	4842128	assert(VXID_TAG(hp->vsl->wid));
252	4842128	i = hdr;
253	4842128	if (i > HTTP_HDR_FIRST)
254	2542867	i = HTTP_HDR_FIRST;
255	4842128	i += hp->logtag;
256	4842128	VSLbt(hp->vsl, (enum VSL_tag_e)i, hp->hd[hdr]);
257	4842128	}
258	4842274	}
259
260		static void
261	36920	http_VSLH_del(const struct http *hp, unsigned hdr)
262		{
263		int i;
264
265	36920	if (hp->vsl != NULL) {
266		/* We don't support unsetting stuff in the first line */
267	36920	assert (hdr >= HTTP_HDR_FIRST);
268	36920	assert(VXID_TAG(hp->vsl->wid));
269	36920	i = (HTTP_HDR_UNSET - HTTP_HDR_METHOD);
270	36920	i += hp->logtag;
271	36920	VSLbt(hp->vsl, (enum VSL_tag_e)i, hp->hd[hdr]);
272	36920	}
273	36920	}
274
275		/--------------------------------------------------------------------/
276
277		void
278	225819	http_VSL_log(const struct http *hp)
279		{
280		unsigned u;
281
282	1972817	for (u = 0; u < hp->nhd; u++)
283	3042464	if (hp->hd[u].b != NULL)
284	1295466	http_VSLH(hp, u);
285	225819	}
286
287		/--------------------------------------------------------------------/
288
289		static void
290	4160	http_fail(const struct http *hp)
291		{
292		char id[WS_ID_SIZE];
293
294	4160	VSC_C_main->losthdr++;
295	4160	WS_Id(hp->ws, id);
296	4160	VSLb(hp->vsl, SLT_Error, "out of workspace (%s)", id);
297	4160	WS_MarkOverflow(hp->ws);
298	4160	}
299
300		/*--------------------------------------------------------------------
301		* List of canonical HTTP response code names from RFC2616
302		*/
303
304		static struct http_msg {
305		unsigned nbr;
306		const char *status;
307		const char *txt;
308		} http_msg[] = {
309		#define HTTP_RESP(n, t) { n, #n, t},
310		#include "tbl/http_response.h"
311		{ 0, "0", NULL }
312		};
313
314		const char *
315	57273	http_Status2Reason(unsigned status, const char **sstr)
316		{
317		struct http_msg *mp;
318
319	57273	status %= 1000;
320	57273	assert(status >= 100);
321	1770237	for (mp = http_msg; mp->nbr != 0 && mp->nbr <= status; mp++)
322	1768437	if (mp->nbr == status) {
323	55473	if (sstr)
324	42477	*sstr = mp->status;
325	55473	return (mp->txt);
326		}
327	1800	return ("Unknown HTTP Status");
328	57273	}
329
330		/--------------------------------------------------------------------/
331
332		unsigned
333	206376	HTTP_estimate(unsigned nhttp)
334		{
335
336		/* XXX: We trust the structs to size-aligned as necessary */
337	206376	return (PRNDUP(sizeof(struct http) + sizeof(txt) * nhttp + nhttp));
338		}
339
340		struct http *
341	619143	HTTP_create(void *p, uint16_t nhttp, unsigned len)
342		{
343		struct http *hp;
344
345	619143	hp = p;
346	619143	hp->magic = HTTP_MAGIC;
347	619143	hp->hd = (void*)(hp + 1);
348	619143	hp->shd = nhttp;
349	619143	hp->hdf = (void*)(hp->hd + nhttp);
350	619143	assert((unsigned char*)p + len == hp->hdf + PRNDUP(nhttp));
351	619143	return (hp);
352		}
353
354		/--------------------------------------------------------------------/
355
356		void
357	577368	HTTP_Setup(struct http hp, struct ws ws, struct vsl_log *vsl,
358		enum VSL_tag_e whence)
359		{
360	577368	http_Teardown(hp);
361	577368	hp->nhd = HTTP_HDR_FIRST;
362	577368	hp->logtag = whence;
363	577368	hp->ws = ws;
364	577368	hp->vsl = vsl;
365	577368	}
366
367		/*--------------------------------------------------------------------
368		* http_Teardown() is a safety feature, we use it to zap all http
369		* structs once we're done with them, to minimize the risk that
370		* old stale pointers exist to no longer valid stuff.
371		*/
372
373		void
374	901510	http_Teardown(struct http *hp)
375		{
376
377	901510	CHECK_OBJ_NOTNULL(hp, HTTP_MAGIC);
378	901510	AN(hp->shd);
379	901510	memset(&hp->nhd, 0, sizeof *hp - offsetof(struct http, nhd));
380	901510	memset(hp->hd, 0, sizeof hp->hd hp->shd);
381	901510	memset(hp->hdf, 0, sizeof hp->hdf hp->shd);
382	901510	}
383
384		/*--------------------------------------------------------------------
385		* Duplicate the http content into another http
386		* We cannot just memcpy the struct because the hd & hdf are private
387		* storage to the struct http.
388		*/
389
390		void
391	253918	HTTP_Dup(struct http to, const struct http fm)
392		{
393
394	253918	assert(fm->nhd <= to->shd);
395	253918	memcpy(to->hd, fm->hd, fm->nhd * sizeof *to->hd);
396	253918	memcpy(to->hdf, fm->hdf, fm->nhd * sizeof *to->hdf);
397	253918	to->nhd = fm->nhd;
398	253918	to->logtag = fm->logtag;
399	253918	to->status = fm->status;
400	253918	to->protover = fm->protover;
401	253918	}
402
403
404		/*--------------------------------------------------------------------
405		* Clone the entire http structure, including vsl & ws
406		*/
407
408		void
409	239281	HTTP_Clone(struct http to, const struct http const fm)
410		{
411
412	239281	HTTP_Dup(to, fm);
413	239281	to->vsl = fm->vsl;
414	239281	to->ws = fm->ws;
415	239281	}
416
417		/--------------------------------------------------------------------/
418
419		void
420	258238	http_Proto(struct http *to)
421		{
422		const char *fm;
423
424	258238	fm = to->hd[HTTP_HDR_PROTO].b;
425
426	516116	if (fm != NULL &&
427	257919	(fm[0] == 'H' \|\| fm[0] == 'h') &&
428	257885	(fm[1] == 'T' \|\| fm[1] == 't') &&
429	257883	(fm[2] == 'T' \|\| fm[2] == 't') &&
430	257883	(fm[3] == 'P' \|\| fm[3] == 'p') &&
431	257883	fm[4] == '/' &&
432	257883	vct_isdigit(fm[5]) &&
433	257881	fm[6] == '.' &&
434	257881	vct_isdigit(fm[7]) &&
435	257878	fm[8] == '\0') {
436	257878	to->protover = 10 * (fm[5] - '0') + (fm[7] - '0');
437	257878	} else {
438	360	to->protover = 0;
439		}
440	258238	}
441
442		/--------------------------------------------------------------------/
443
444		void
445	1531435	http_SetH(struct http to, unsigned n, const char header)
446		{
447
448	1531435	assert(n < to->nhd);
449	1531435	AN(header);
450	1531435	to->hd[n].b = TRUST_ME(header);
451	1531435	to->hd[n].e = strchr(to->hd[n].b, '\0');
452	1531435	to->hdf[n] = 0;
453	1531435	http_VSLH(to, n);
454	1531435	if (n == HTTP_HDR_PROTO)
455	52355	http_Proto(to);
456	1531435	}
457
458		/--------------------------------------------------------------------/
459
460		static void
461	1440	http_PutField(struct http to, int field, const char string)
462		{
463		const char *p;
464
465	1440	CHECK_OBJ_NOTNULL(to, HTTP_MAGIC);
466	1440	p = WS_Copy(to->ws, string, -1);
467	1440	if (p == NULL) {
468	40	http_fail(to);
469	40	VSLbs(to->vsl, SLT_LostHeader, TOSTRAND(string));
470	40	return;
471		}
472	1400	http_SetH(to, field, p);
473	1440	}
474
475		/--------------------------------------------------------------------/
476
477		int
478	4567691	http_IsHdr(const txt *hh, hdr_t hdr)
479		{
480		unsigned l;
481
482	4567691	Tcheck(*hh);
483	4567691	AN(hdr);
484	4567691	l = hdr[0];
485	4567691	assert(l == strlen(hdr + 1));
486	4567691	assert(hdr[l] == ':');
487	4567691	hdr++;
488	4567691	return (http_hdr_at(hdr, hh->b, l));
489		}
490
491		/--------------------------------------------------------------------/
492
493		static unsigned
494	5835784	http_findhdr(const struct http hp, unsigned l, const char hdr)
495		{
496		unsigned u;
497
498	25185454	for (u = HTTP_HDR_FIRST; u < hp->nhd; u++) {
499	20632882	Tcheck(hp->hd[u]);