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Diffstat (limited to '')
| -rw-r--r-- | src/h2.c | 814 |
1 files changed, 814 insertions, 0 deletions
diff --git a/src/h2.c b/src/h2.c new file mode 100644 index 0000000..f794262 --- /dev/null +++ b/src/h2.c @@ -0,0 +1,814 @@ +/* + * HTTP/2 protocol processing + * + * Copyright 2017 Willy Tarreau <w@1wt.eu> + * Copyright (C) 2017 HAProxy Technologies + * + * Permission is hereby granted, free of charge, to any person obtaining + * a copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES + * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT + * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR + * OTHER DEALINGS IN THE SOFTWARE. + */ + +#include <inttypes.h> +#include <haproxy/api.h> +#include <haproxy/global.h> +#include <haproxy/h2.h> +#include <haproxy/http-hdr-t.h> +#include <haproxy/http.h> +#include <haproxy/http_htx.h> +#include <haproxy/htx.h> +#include <import/ist.h> + + +struct h2_frame_definition h2_frame_definition[H2_FT_ENTRIES] = { + [H2_FT_DATA ] = { .dir = 3, .min_id = 1, .max_id = H2_MAX_STREAM_ID, .min_len = 0, .max_len = H2_MAX_FRAME_LEN, }, + [H2_FT_HEADERS ] = { .dir = 3, .min_id = 1, .max_id = H2_MAX_STREAM_ID, .min_len = 1, .max_len = H2_MAX_FRAME_LEN, }, + [H2_FT_PRIORITY ] = { .dir = 3, .min_id = 1, .max_id = H2_MAX_STREAM_ID, .min_len = 5, .max_len = 5, }, + [H2_FT_RST_STREAM ] = { .dir = 3, .min_id = 1, .max_id = H2_MAX_STREAM_ID, .min_len = 4, .max_len = 4, }, + [H2_FT_SETTINGS ] = { .dir = 3, .min_id = 0, .max_id = 0, .min_len = 0, .max_len = H2_MAX_FRAME_LEN, }, + [H2_FT_PUSH_PROMISE ] = { .dir = 0, .min_id = 1, .max_id = H2_MAX_STREAM_ID, .min_len = 4, .max_len = H2_MAX_FRAME_LEN, }, + [H2_FT_PING ] = { .dir = 3, .min_id = 0, .max_id = 0, .min_len = 8, .max_len = 8, }, + [H2_FT_GOAWAY ] = { .dir = 3, .min_id = 0, .max_id = 0, .min_len = 8, .max_len = H2_MAX_FRAME_LEN, }, + [H2_FT_WINDOW_UPDATE] = { .dir = 3, .min_id = 0, .max_id = H2_MAX_STREAM_ID, .min_len = 4, .max_len = 4, }, + [H2_FT_CONTINUATION ] = { .dir = 3, .min_id = 1, .max_id = H2_MAX_STREAM_ID, .min_len = 0, .max_len = H2_MAX_FRAME_LEN, }, +}; + +/* Looks into <ist> for forbidden characters for header values (0x00, 0x0A, + * 0x0D), starting at pointer <start> which must be within <ist>. Returns + * non-zero if such a character is found, 0 otherwise. When run on unlikely + * header match, it's recommended to first check for the presence of control + * chars using ist_find_ctl(). + */ +static int has_forbidden_char(const struct ist ist, const char *start) +{ + do { + if ((uint8_t)*start <= 0x0d && + (1U << (uint8_t)*start) & ((1<<13) | (1<<10) | (1<<0))) + return 1; + start++; + } while (start < istend(ist)); + return 0; +} + +/* Prepare the request line into <htx> from pseudo headers stored in <phdr[]>. + * <fields> indicates what was found so far. This should be called once at the + * detection of the first general header field or at the end of the request if + * no general header field was found yet. Returns the created start line on + * success, or NULL on failure. Upon success, <msgf> is updated with a few + * H2_MSGF_* flags indicating what was found while parsing. + * + * The rules below deserve a bit of explanation. There tends to be some + * confusion regarding H2's authority vs the Host header. They are different + * though may sometimes be exchanged. In H2, the request line is broken into : + * - :method + * - :scheme + * - :authority + * - :path + * + * An equivalent HTTP/1.x absolute-form request would then look like : + * <:method> <:scheme>://<:authority><:path> HTTP/x.y + * + * Except for CONNECT which doesn't have scheme nor path and looks like : + * <:method> <:authority> HTTP/x.y + * + * It's worth noting that H2 still supports an encoding to map H1 origin-form + * and asterisk-form requests. These ones do not specify the authority. However + * in H2 they must still specify the scheme, which is not present in H1. Also, + * when encoding an absolute-form H1 request without a path, the path + * automatically becomes "/" except for the OPTIONS method where it + * becomes "*". + * + * As such it is explicitly permitted for an H2 client to send a request + * featuring a Host header and no :authority, though it's not the recommended + * way to use H2 for a client. It is however the only permitted way to encode + * an origin-form H1 request over H2. Thus we need to respect such differences + * as much as possible when re-encoding the H2 request into HTX. + */ +static struct htx_sl *h2_prepare_htx_reqline(uint32_t fields, struct ist *phdr, struct htx *htx, unsigned int *msgf) +{ + struct ist uri, meth_sl; + unsigned int flags = HTX_SL_F_NONE; + struct htx_sl *sl; + size_t i; + + if ((fields & H2_PHDR_FND_METH) && isteq(phdr[H2_PHDR_IDX_METH], ist("CONNECT"))) { + if (fields & H2_PHDR_FND_PROT) { + /* rfc 8441 Extended Connect Protocol + * #4 :scheme and :path must be present, as well as + * :authority like all h2 requests + */ + if (!(fields & H2_PHDR_FND_SCHM)) { + /* missing scheme */ + goto fail; + } + else if (!(fields & H2_PHDR_FND_PATH)) { + /* missing path */ + goto fail; + } + else if (!(fields & H2_PHDR_FND_AUTH)) { + /* missing authority */ + goto fail; + } + + flags |= HTX_SL_F_HAS_SCHM; + if (isteqi(phdr[H2_PHDR_IDX_SCHM], ist("http"))) + flags |= HTX_SL_F_SCHM_HTTP; + else if (isteqi(phdr[H2_PHDR_IDX_SCHM], ist("https"))) + flags |= HTX_SL_F_SCHM_HTTPS; + else if (!http_validate_scheme(phdr[H2_PHDR_IDX_SCHM])) + htx->flags |= HTX_FL_PARSING_ERROR; + + meth_sl = ist("GET"); + + *msgf |= H2_MSGF_EXT_CONNECT; + /* no ES on the HEADERS frame but no body either for + * Extended CONNECT */ + *msgf &= ~H2_MSGF_BODY; + } + else { + /* RFC 7540 #8.2.6 regarding CONNECT: ":scheme" and ":path" + * MUST be omitted ; ":authority" contains the host and port + * to connect to. + */ + if (fields & H2_PHDR_FND_SCHM) { + /* scheme not allowed */ + goto fail; + } + else if (fields & H2_PHDR_FND_PATH) { + /* path not allowed */ + goto fail; + } + else if (!(fields & H2_PHDR_FND_AUTH)) { + /* missing authority */ + goto fail; + } + + meth_sl = phdr[H2_PHDR_IDX_METH]; + } + + *msgf |= H2_MSGF_BODY_TUNNEL; + } + else if ((fields & (H2_PHDR_FND_METH|H2_PHDR_FND_SCHM|H2_PHDR_FND_PATH)) != + (H2_PHDR_FND_METH|H2_PHDR_FND_SCHM|H2_PHDR_FND_PATH)) { + /* RFC 7540 #8.1.2.3 : all requests MUST include exactly one + * valid value for the ":method", ":scheme" and ":path" phdr + * unless it is a CONNECT request. + */ + if (!(fields & H2_PHDR_FND_METH)) { + /* missing method */ + goto fail; + } + else if (!(fields & H2_PHDR_FND_SCHM)) { + /* missing scheme */ + goto fail; + } + else { + /* missing path */ + goto fail; + } + } + else { /* regular methods */ + /* RFC3986#6.2.2.1: scheme is case-insensitive. We need to + * classify the scheme as "present/http", "present/https", + * "present/other", "absent" so as to decide whether or not + * we're facing a normalized URI that will have to be encoded + * in origin or absolute form. Indeed, 7540#8.1.2.3 says that + * clients should use the absolute form, thus we cannot infer + * whether or not the client wanted to use a proxy here. + */ + flags |= HTX_SL_F_HAS_SCHM; + if (isteqi(phdr[H2_PHDR_IDX_SCHM], ist("http"))) + flags |= HTX_SL_F_SCHM_HTTP; + else if (isteqi(phdr[H2_PHDR_IDX_SCHM], ist("https"))) + flags |= HTX_SL_F_SCHM_HTTPS; + else if (!http_validate_scheme(phdr[H2_PHDR_IDX_SCHM])) + htx->flags |= HTX_FL_PARSING_ERROR; + + meth_sl = phdr[H2_PHDR_IDX_METH]; + } + + if (fields & H2_PHDR_FND_PATH) { + /* 7540#8.1.2.3: :path must not be empty, and must be either + * '*' or an RFC3986 "path-absolute" starting with a "/" but + * not with "//". + * However, this "path-absolute" was a mistake which was + * later fixed in http2bis as "absolute-path" to match + * HTTP/1, thus also allowing "//". + */ + if (unlikely(!phdr[H2_PHDR_IDX_PATH].len)) + goto fail; + else if (unlikely(phdr[H2_PHDR_IDX_PATH].ptr[0] != '/')) { + if (!isteq(phdr[H2_PHDR_IDX_PATH], ist("*"))) + goto fail; + } + } + + if (!(flags & HTX_SL_F_HAS_SCHM)) { + /* no scheme, use authority only (CONNECT) */ + uri = phdr[H2_PHDR_IDX_AUTH]; + flags |= HTX_SL_F_HAS_AUTHORITY; + } + else if (fields & H2_PHDR_FND_AUTH) { + /* authority is present, let's use the absolute form. We simply + * use the trash to concatenate them since all of them MUST fit + * in a bufsize since it's where they come from. + */ + uri = ist2bin(trash.area, phdr[H2_PHDR_IDX_SCHM]); + istcat(&uri, ist("://"), trash.size); + istcat(&uri, phdr[H2_PHDR_IDX_AUTH], trash.size); + if (!isteq(phdr[H2_PHDR_IDX_PATH], ist("*"))) + istcat(&uri, phdr[H2_PHDR_IDX_PATH], trash.size); + flags |= HTX_SL_F_HAS_AUTHORITY; + + if (flags & (HTX_SL_F_SCHM_HTTP|HTX_SL_F_SCHM_HTTPS)) { + /* we don't know if it was originally an absolute or a + * relative request because newer versions of HTTP use + * the absolute URI format by default, which we call + * the normalized URI format internally. This is the + * strongly recommended way of sending a request for + * a regular client, so we cannot distinguish this + * from a request intended for a proxy. For other + * schemes however there is no doubt. + */ + flags |= HTX_SL_F_NORMALIZED_URI; + } + } + else { + /* usual schemes with or without authority, use origin form */ + uri = phdr[H2_PHDR_IDX_PATH]; + if (fields & H2_PHDR_FND_AUTH) + flags |= HTX_SL_F_HAS_AUTHORITY; + } + + /* The method is a non-empty token (RFC7231#4.1) */ + if (!meth_sl.len) + goto fail; + for (i = 0; i < meth_sl.len; i++) { + if (!HTTP_IS_TOKEN(meth_sl.ptr[i])) + htx->flags |= HTX_FL_PARSING_ERROR; + } + + /* make sure the final URI isn't empty. Note that 7540#8.1.2.3 states + * that :path must not be empty. + */ + if (!uri.len) + goto fail; + + /* The final URI must not contain LWS nor CTL characters */ + for (i = 0; i < uri.len; i++) { + unsigned char c = uri.ptr[i]; + if (HTTP_IS_LWS(c) || HTTP_IS_CTL(c)) + htx->flags |= HTX_FL_PARSING_ERROR; + } + + /* Set HTX start-line flags */ + flags |= HTX_SL_F_VER_11; // V2 in fact + flags |= HTX_SL_F_XFER_LEN; // xfer len always known with H2 + + sl = htx_add_stline(htx, HTX_BLK_REQ_SL, flags, meth_sl, uri, ist("HTTP/2.0")); + if (!sl) + goto fail; + + sl->info.req.meth = find_http_meth(meth_sl.ptr, meth_sl.len); + if (sl->info.req.meth == HTTP_METH_HEAD) + *msgf |= H2_MSGF_BODYLESS_RSP; + return sl; + fail: + return NULL; +} + +/* Takes an H2 request present in the headers list <list> terminated by a name + * being <NULL,0> and emits the equivalent HTX request according to the rules + * documented in RFC7540 #8.1.2. The output contents are emitted in <htx>, and + * non-zero is returned if some bytes were emitted. In case of error, a + * negative error code is returned. + * + * Upon success, <msgf> is filled with a few H2_MSGF_* flags indicating what + * was found while parsing. The caller must set it to zero in or H2_MSGF_BODY + * if a body is detected (!ES). + * + * The headers list <list> must be composed of : + * - n.name != NULL, n.len > 0 : literal header name + * - n.name == NULL, n.len > 0 : indexed pseudo header name number <n.len> + * among H2_PHDR_IDX_* + * - n.name ignored, n.len == 0 : end of list + * - in all cases except the end of list, v.name and v.len must designate a + * valid value. + * + * The Cookie header will be reassembled at the end, and for this, the <list> + * will be used to create a linked list, so its contents may be destroyed. + */ +int h2_make_htx_request(struct http_hdr *list, struct htx *htx, unsigned int *msgf, unsigned long long *body_len) +{ + struct ist phdr_val[H2_PHDR_NUM_ENTRIES]; + uint32_t fields; /* bit mask of H2_PHDR_FND_* */ + uint32_t idx; + int ck, lck; /* cookie index and last cookie index */ + int phdr; + int ret; + int i; + struct htx_sl *sl = NULL; + unsigned int sl_flags = 0; + const char *ctl; + + lck = ck = -1; // no cookie for now + fields = 0; + for (idx = 0; list[idx].n.len != 0; idx++) { + if (!isttest(list[idx].n)) { + /* this is an indexed pseudo-header */ + phdr = list[idx].n.len; + } + else { + /* this can be any type of header */ + /* RFC7540#8.1.2: upper case not allowed in header field names. + * #10.3: header names must be valid (i.e. match a token). + * For pseudo-headers we check from 2nd char and for other ones + * from the first char, because HTTP_IS_TOKEN() also excludes + * the colon. + */ + phdr = h2_str_to_phdr(list[idx].n); + + for (i = !!phdr; i < list[idx].n.len; i++) + if ((uint8_t)(list[idx].n.ptr[i] - 'A') < 'Z' - 'A' || !HTTP_IS_TOKEN(list[idx].n.ptr[i])) + goto fail; + } + + /* RFC7540#10.3: intermediaries forwarding to HTTP/1 must take care of + * rejecting NUL, CR and LF characters. + */ + ctl = ist_find_ctl(list[idx].v); + if (unlikely(ctl) && has_forbidden_char(list[idx].v, ctl)) + goto fail; + + if (phdr > 0 && phdr < H2_PHDR_NUM_ENTRIES) { + /* insert a pseudo header by its index (in phdr) and value (in value) */ + if (fields & ((1 << phdr) | H2_PHDR_FND_NONE)) { + if (fields & H2_PHDR_FND_NONE) { + /* pseudo header field after regular headers */ + goto fail; + } + else { + /* repeated pseudo header field */ + goto fail; + } + } + fields |= 1 << phdr; + phdr_val[phdr] = list[idx].v; + continue; + } + else if (phdr != 0) { + /* invalid pseudo header -- should never happen here */ + goto fail; + } + + /* regular header field in (name,value) */ + if (unlikely(!(fields & H2_PHDR_FND_NONE))) { + /* no more pseudo-headers, time to build the request line */ + sl = h2_prepare_htx_reqline(fields, phdr_val, htx, msgf); + if (!sl) + goto fail; + fields |= H2_PHDR_FND_NONE; + + /* http2bis draft recommends to drop Host in favor of :authority when + * the latter is present. This is required to make sure there is no + * discrepancy between the authority and the host header, especially + * since routing rules usually involve Host. Here we already know if + * :authority was found so we can emit it right now and mark the host + * as filled so that it's skipped later. + */ + if (fields & H2_PHDR_FND_AUTH) { + if (!htx_add_header(htx, ist("host"), phdr_val[H2_PHDR_IDX_AUTH])) + goto fail; + fields |= H2_PHDR_FND_HOST; + } + } + + if (isteq(list[idx].n, ist("host"))) { + if (fields & H2_PHDR_FND_HOST) + continue; + + fields |= H2_PHDR_FND_HOST; + } + + if (isteq(list[idx].n, ist("content-length"))) { + ret = http_parse_cont_len_header(&list[idx].v, body_len, + *msgf & H2_MSGF_BODY_CL); + if (ret < 0) + goto fail; + + *msgf |= H2_MSGF_BODY_CL; + sl_flags |= HTX_SL_F_CLEN; + if (ret == 0) + continue; // skip this duplicate + } + + /* these ones are forbidden in requests (RFC7540#8.1.2.2) */ + if (isteq(list[idx].n, ist("connection")) || + isteq(list[idx].n, ist("proxy-connection")) || + isteq(list[idx].n, ist("keep-alive")) || + isteq(list[idx].n, ist("upgrade")) || + isteq(list[idx].n, ist("transfer-encoding"))) + goto fail; + + if (isteq(list[idx].n, ist("te")) && !isteq(list[idx].v, ist("trailers"))) + goto fail; + + /* cookie requires special processing at the end */ + if (isteq(list[idx].n, ist("cookie"))) { + http_cookie_register(list, idx, &ck, &lck); + continue; + } + + if (!htx_add_header(htx, list[idx].n, list[idx].v)) + goto fail; + } + + /* RFC7540#8.1.2.1 mandates to reject response pseudo-headers (:status) */ + if (fields & H2_PHDR_FND_STAT) + goto fail; + + /* Let's dump the request now if not yet emitted. */ + if (!(fields & H2_PHDR_FND_NONE)) { + sl = h2_prepare_htx_reqline(fields, phdr_val, htx, msgf); + if (!sl) + goto fail; + } + + if (*msgf & H2_MSGF_BODY_TUNNEL) + *msgf &= ~(H2_MSGF_BODY|H2_MSGF_BODY_CL); + + if (!(*msgf & H2_MSGF_BODY) || ((*msgf & H2_MSGF_BODY_CL) && *body_len == 0) || + (*msgf & H2_MSGF_BODY_TUNNEL)) { + /* Request without body or tunnel requested */ + sl_flags |= HTX_SL_F_BODYLESS; + htx->flags |= HTX_FL_EOM; + } + + if (*msgf & H2_MSGF_EXT_CONNECT) { + if (!htx_add_header(htx, ist("upgrade"), phdr_val[H2_PHDR_IDX_PROT])) + goto fail; + if (!htx_add_header(htx, ist("connection"), ist("upgrade"))) + goto fail; + sl_flags |= HTX_SL_F_CONN_UPG; + } + + /* update the start line with last detected header info */ + sl->flags |= sl_flags; + + /* complete with missing Host if needed (we may validate this test if + * no regular header was found). + */ + if ((fields & (H2_PHDR_FND_HOST|H2_PHDR_FND_AUTH)) == H2_PHDR_FND_AUTH) { + /* missing Host field, use :authority instead */ + if (!htx_add_header(htx, ist("host"), phdr_val[H2_PHDR_IDX_AUTH])) + goto fail; + } + + /* now we may have to build a cookie list. We'll dump the values of all + * visited headers. + */ + if (ck >= 0) { + if (http_cookie_merge(htx, list, ck)) + goto fail; + } + + /* now send the end of headers marker */ + if (!htx_add_endof(htx, HTX_BLK_EOH)) + goto fail; + + /* proceed to scheme-based normalization on target-URI */ + if (fields & H2_PHDR_FND_SCHM) + http_scheme_based_normalize(htx); + + ret = 1; + return ret; + + fail: + return -1; +} + +/* Prepare the status line into <htx> from pseudo headers stored in <phdr[]>. + * <fields> indicates what was found so far. This should be called once at the + * detection of the first general header field or at the end of the message if + * no general header field was found yet. Returns the created start line on + * success, or NULL on failure. Upon success, <msgf> is updated with a few + * H2_MSGF_* flags indicating what was found while parsing. + */ +static struct htx_sl *h2_prepare_htx_stsline(uint32_t fields, struct ist *phdr, struct htx *htx, unsigned int *msgf) +{ + unsigned int status, flags = HTX_SL_F_IS_RESP; + struct htx_sl *sl; + struct ist stat; + + /* only :status is allowed as a pseudo header */ + if (!(fields & H2_PHDR_FND_STAT)) + goto fail; + + if (phdr[H2_PHDR_IDX_STAT].len != 3) + goto fail; + + /* if Extended CONNECT is used, convert status code from 200 to htx 101 + * following rfc 8441 */ + if (unlikely(*msgf & H2_MSGF_EXT_CONNECT) && + isteq(phdr[H2_PHDR_IDX_STAT], ist("200"))) { + stat = ist("101"); + status = 101; + } + else { + unsigned char h, t, u; + + stat = phdr[H2_PHDR_IDX_STAT]; + + h = stat.ptr[0] - '0'; + t = stat.ptr[1] - '0'; + u = stat.ptr[2] - '0'; + if (h > 9 || t > 9 || u > 9) + goto fail; + status = h * 100 + t * 10 + u; + } + + /* 101 responses are not supported in H2, so return a error. + * On 1xx responses there is no ES on the HEADERS frame but there is no + * body. So remove the flag H2_MSGF_BODY and add H2_MSGF_RSP_1XX to + * notify the decoder another HEADERS frame is expected. + * 204/304 response have no body by definition. So remove the flag + * H2_MSGF_BODY and set H2_MSGF_BODYLESS_RSP. + * + * Note however that there is a special condition for Extended CONNECT. + * In this case, we explicitly convert it to HTX 101 to mimic + * Get+Upgrade HTTP/1.1 mechanism + */ + if (status == 101) { + if (!(*msgf & H2_MSGF_EXT_CONNECT)) + goto fail; + } + else if (status < 200) { + *msgf |= H2_MSGF_RSP_1XX; + *msgf &= ~H2_MSGF_BODY; + } + else if (status == 204 || status == 304) { + *msgf &= ~H2_MSGF_BODY; + *msgf |= H2_MSGF_BODYLESS_RSP; + } + + /* Set HTX start-line flags */ + flags |= HTX_SL_F_VER_11; // V2 in fact + flags |= HTX_SL_F_XFER_LEN; // xfer len always known with H2 + + sl = htx_add_stline(htx, HTX_BLK_RES_SL, flags, ist("HTTP/2.0"), stat, ist("")); + if (!sl) + goto fail; + sl->info.res.status = status; + return sl; + fail: + return NULL; +} + +/* Takes an H2 response present in the headers list <list> terminated by a name + * being <NULL,0> and emits the equivalent HTX response according to the rules + * documented in RFC7540 #8.1.2. The output contents are emitted in <htx>, and + * a positive value is returned if some bytes were emitted. In case of error, a + * negative error code is returned. + * + * Upon success, <msgf> is filled with a few H2_MSGF_* flags indicating what + * was found while parsing. The caller must set it to zero in or H2_MSGF_BODY + * if a body is detected (!ES). + * + * The headers list <list> must be composed of : + * - n.name != NULL, n.len > 0 : literal header name + * - n.name == NULL, n.len > 0 : indexed pseudo header name number <n.len> + * among H2_PHDR_IDX_* + * - n.name ignored, n.len == 0 : end of list + * - in all cases except the end of list, v.name and v.len must designate a + * valid value. + * + * <upgrade_protocol> is only used if the htx status code is 101 indicating a + * response to an upgrade or h2-equivalent request. + */ +int h2_make_htx_response(struct http_hdr *list, struct htx *htx, unsigned int *msgf, unsigned long long *body_len, char *upgrade_protocol) +{ + struct ist phdr_val[H2_PHDR_NUM_ENTRIES]; + uint32_t fields; /* bit mask of H2_PHDR_FND_* */ + uint32_t idx; + int phdr; + int ret; + int i; + struct htx_sl *sl = NULL; + unsigned int sl_flags = 0; + const char *ctl; + + fields = 0; + for (idx = 0; list[idx].n.len != 0; idx++) { + if (!isttest(list[idx].n)) { + /* this is an indexed pseudo-header */ + phdr = list[idx].n.len; + } + else { + /* this can be any type of header */ + /* RFC7540#8.1.2: upper case not allowed in header field names. + * #10.3: header names must be valid (i.e. match a token). + * For pseudo-headers we check from 2nd char and for other ones + * from the first char, because HTTP_IS_TOKEN() also excludes + * the colon. + */ + phdr = h2_str_to_phdr(list[idx].n); + + for (i = !!phdr; i < list[idx].n.len; i++) + if ((uint8_t)(list[idx].n.ptr[i] - 'A') < 'Z' - 'A' || !HTTP_IS_TOKEN(list[idx].n.ptr[i])) + goto fail; + } + + /* RFC7540#10.3: intermediaries forwarding to HTTP/1 must take care of + * rejecting NUL, CR and LF characters. + */ + ctl = ist_find_ctl(list[idx].v); + if (unlikely(ctl) && has_forbidden_char(list[idx].v, ctl)) + goto fail; + + if (phdr > 0 && phdr < H2_PHDR_NUM_ENTRIES) { + /* insert a pseudo header by its index (in phdr) and value (in value) */ + if (fields & ((1 << phdr) | H2_PHDR_FND_NONE)) { + if (fields & H2_PHDR_FND_NONE) { + /* pseudo header field after regular headers */ + goto fail; + } + else { + /* repeated pseudo header field */ + goto fail; + } + } + fields |= 1 << phdr; + phdr_val[phdr] = list[idx].v; + continue; + } + else if (phdr != 0) { + /* invalid pseudo header -- should never happen here */ + goto fail; + } + + /* regular header field in (name,value) */ + if (!(fields & H2_PHDR_FND_NONE)) { + /* no more pseudo-headers, time to build the status line */ + sl = h2_prepare_htx_stsline(fields, phdr_val, htx, msgf); + if (!sl) + goto fail; + fields |= H2_PHDR_FND_NONE; + } + + if (isteq(list[idx].n, ist("content-length"))) { + ret = http_parse_cont_len_header(&list[idx].v, body_len, + *msgf & H2_MSGF_BODY_CL); + if (ret < 0) + goto fail; + + *msgf |= H2_MSGF_BODY_CL; + sl_flags |= HTX_SL_F_CLEN; + if (ret == 0) + continue; // skip this duplicate + } + + /* these ones are forbidden in responses (RFC7540#8.1.2.2) */ + if (isteq(list[idx].n, ist("connection")) || + isteq(list[idx].n, ist("proxy-connection")) || + isteq(list[idx].n, ist("keep-alive")) || + isteq(list[idx].n, ist("upgrade")) || + isteq(list[idx].n, ist("transfer-encoding"))) + goto fail; + + if (!htx_add_header(htx, list[idx].n, list[idx].v)) + goto fail; + } + + /* RFC7540#8.1.2.1 mandates to reject request pseudo-headers */ + if (fields & (H2_PHDR_FND_AUTH|H2_PHDR_FND_METH|H2_PHDR_FND_PATH|H2_PHDR_FND_SCHM)) + goto fail; + + /* Let's dump the request now if not yet emitted. */ + if (!(fields & H2_PHDR_FND_NONE)) { + sl = h2_prepare_htx_stsline(fields, phdr_val, htx, msgf); + if (!sl) + goto fail; + } + + if (sl->info.res.status == 101 && upgrade_protocol) { + if (!htx_add_header(htx, ist("connection"), ist("upgrade"))) + goto fail; + if (!htx_add_header(htx, ist("upgrade"), ist(upgrade_protocol))) + goto fail; + sl_flags |= HTX_SL_F_CONN_UPG; + } + + if ((*msgf & H2_MSGF_BODY_TUNNEL) && + ((sl->info.res.status >= 200 && sl->info.res.status < 300) || sl->info.res.status == 101)) + *msgf &= ~(H2_MSGF_BODY|H2_MSGF_BODY_CL); + else + *msgf &= ~H2_MSGF_BODY_TUNNEL; + + if (!(*msgf & H2_MSGF_BODY) || ((*msgf & H2_MSGF_BODY_CL) && *body_len == 0) || + (*msgf & H2_MSGF_BODY_TUNNEL)) { + /* Response without body or tunnel successfully established */ + sl_flags |= HTX_SL_F_BODYLESS; + htx->flags |= HTX_FL_EOM; + } + + /* update the start line with last detected header info */ + sl->flags |= sl_flags; + + if ((*msgf & (H2_MSGF_BODY|H2_MSGF_BODY_TUNNEL|H2_MSGF_BODY_CL)) == H2_MSGF_BODY) { + /* FIXME: Do we need to signal anything when we have a body and + * no content-length, to have the equivalent of H1's chunked + * encoding? + */ + } + + /* now send the end of headers marker */ + if (!htx_add_endof(htx, HTX_BLK_EOH)) + goto fail; + + ret = 1; + return ret; + + fail: + return -1; +} + +/* Takes an H2 headers list <list> terminated by a name being <NULL,0> and emits + * the equivalent HTX trailers blocks. The output contents are emitted in <htx>, + * and a positive value is returned if some bytes were emitted. In case of + * error, a negative error code is returned. The caller must have verified that + * the message in the buffer is compatible with receipt of trailers. + * + * The headers list <list> must be composed of : + * - n.name != NULL, n.len > 0 : literal header name + * - n.name == NULL, n.len > 0 : indexed pseudo header name number <n.len> + * among H2_PHDR_IDX_* (illegal here) + * - n.name ignored, n.len == 0 : end of list + * - in all cases except the end of list, v.name and v.len must designate a + * valid value. + */ +int h2_make_htx_trailers(struct http_hdr *list, struct htx *htx) +{ + const char *ctl; + uint32_t idx; + int i; + + for (idx = 0; list[idx].n.len != 0; idx++) { + if (!isttest(list[idx].n)) { + /* This is an indexed pseudo-header (RFC7540#8.1.2.1) */ + goto fail; + } + + /* RFC7540#8.1.2: upper case not allowed in header field names. + * #10.3: header names must be valid (i.e. match a token). This + * also catches pseudo-headers which are forbidden in trailers. + */ + for (i = 0; i < list[idx].n.len; i++) + if ((uint8_t)(list[idx].n.ptr[i] - 'A') < 'Z' - 'A' || !HTTP_IS_TOKEN(list[idx].n.ptr[i])) + goto fail; + + /* these ones are forbidden in trailers (RFC7540#8.1.2.2) */ + if (isteq(list[idx].n, ist("host")) || + isteq(list[idx].n, ist("content-length")) || + isteq(list[idx].n, ist("connection")) || + isteq(list[idx].n, ist("proxy-connection")) || + isteq(list[idx].n, ist("keep-alive")) || + isteq(list[idx].n, ist("upgrade")) || + isteq(list[idx].n, ist("te")) || + isteq(list[idx].n, ist("transfer-encoding"))) + goto fail; + + /* RFC7540#10.3: intermediaries forwarding to HTTP/1 must take care of + * rejecting NUL, CR and LF characters. + */ + ctl = ist_find_ctl(list[idx].v); + if (unlikely(ctl) && has_forbidden_char(list[idx].v, ctl)) + goto fail; + + if (!htx_add_trailer(htx, list[idx].n, list[idx].v)) + goto fail; + } + + if (!htx_add_endof(htx, HTX_BLK_EOT)) + goto fail; + + return 1; + + fail: + return -1; +} |