/* * include/haproxy/h1.h * This file contains HTTP/1 protocol definitions. * * Copyright (C) 2000-2020 Willy Tarreau - w@1wt.eu * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation, version 2.1 * exclusively. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef _HAPROXY_H1_H #define _HAPROXY_H1_H #include #include #include #include #include #include /* Possible states while parsing HTTP/1 messages (request|response) */ enum h1m_state { H1_MSG_RQBEFORE = 0, // request: leading LF, before start line H1_MSG_RQBEFORE_CR = 1, // request: leading CRLF, before start line /* these ones define a request start line */ H1_MSG_RQMETH = 2, // parsing the Method H1_MSG_RQMETH_SP = 3, // space(s) after the Method H1_MSG_RQURI = 4, // parsing the Request URI H1_MSG_RQURI_SP = 5, // space(s) after the Request URI H1_MSG_RQVER = 6, // parsing the Request Version H1_MSG_RQLINE_END = 7, // end of request line (CR or LF) H1_MSG_RPBEFORE = 8, // response: leading LF, before start line H1_MSG_RPBEFORE_CR = 9, // response: leading CRLF, before start line /* these ones define a response start line */ H1_MSG_RPVER = 10, // parsing the Response Version H1_MSG_RPVER_SP = 11, // space(s) after the Response Version H1_MSG_RPCODE = 12, // response code H1_MSG_RPCODE_SP = 13, // space(s) after the response code H1_MSG_RPREASON = 14, // response reason H1_MSG_RPLINE_END = 15, // end of response line (CR or LF) /* common header processing */ H1_MSG_HDR_FIRST = 16, // waiting for first header or last CRLF (no LWS possible) H1_MSG_HDR_NAME = 17, // parsing header name H1_MSG_HDR_COL = 18, // parsing header colon H1_MSG_HDR_L1_SP = 19, // parsing header LWS (SP|HT) before value H1_MSG_HDR_L1_LF = 20, // parsing header LWS (LF) before value H1_MSG_HDR_L1_LWS = 21, // checking whether it's a new header or an LWS H1_MSG_HDR_VAL = 22, // parsing header value H1_MSG_HDR_L2_LF = 23, // parsing header LWS (LF) inside/after value H1_MSG_HDR_L2_LWS = 24, // checking whether it's a new header or an LWS H1_MSG_LAST_LF = 25, // parsing last LF, last state for headers /* Body processing. */ H1_MSG_CHUNK_SIZE = 26, // parsing the chunk size (RFC7230 #4.1) H1_MSG_DATA = 27, // skipping data chunk / content-length data H1_MSG_CHUNK_CRLF = 28, // skipping CRLF after data chunk H1_MSG_TRAILERS = 29, // trailers (post-data entity headers) /* we enter this state when we've received the end of the current message */ H1_MSG_DONE = 30, // message end received, waiting for resync or close H1_MSG_TUNNEL = 31, // tunneled data after DONE } __attribute__((packed)); /* HTTP/1 message flags (32 bit), for use in h1m->flags only */ #define H1_MF_NONE 0x00000000 #define H1_MF_CLEN 0x00000001 // content-length present #define H1_MF_CHNK 0x00000002 // chunk present, exclusive with c-l #define H1_MF_RESP 0x00000004 // this message is the response message #define H1_MF_TOLOWER 0x00000008 // turn the header names to lower case #define H1_MF_VER_11 0x00000010 // message indicates version 1.1 or above #define H1_MF_CONN_CLO 0x00000020 // message contains "connection: close" #define H1_MF_CONN_KAL 0x00000040 // message contains "connection: keep-alive" #define H1_MF_CONN_UPG 0x00000080 // message contains "connection: upgrade" #define H1_MF_XFER_LEN 0x00000100 // message xfer size can be determined #define H1_MF_XFER_ENC 0x00000200 // transfer-encoding is present #define H1_MF_NO_PHDR 0x00000400 // don't add pseudo-headers in the header list #define H1_MF_HDRS_ONLY 0x00000800 // parse headers only #define H1_MF_CLEAN_CONN_HDR 0x00001000 // skip close/keep-alive values of connection headers during parsing #define H1_MF_METH_CONNECT 0x00002000 // Set for a response to a CONNECT request #define H1_MF_METH_HEAD 0x00004000 // Set for a response to a HEAD request /* Note: for a connection to be persistent, we need this for the request : * - one of CLEN or CHNK * - version 1.0 and KAL and not CLO * - or version 1.1 and not CLO * For the response it's the same except that UPG must not appear either. * So in short, for a request it's (CLEN|CHNK) > 0 && !CLO && (VER_11 || KAL) * and for a response it's (CLEN|CHNK) > 0 && !(CLO|UPG) && (VER_11 || KAL) */ /* basic HTTP/1 message state for use in parsers. The err_pos field is special, * it is pre-set to a negative value (-1 or -2), and once non-negative it contains * the relative position in the message of the first parse error. -2 is used to tell * the parser that we want to block the invalid message. -1 is used to only perform * a silent capture. */ struct h1m { enum h1m_state state; // H1 message state (H1_MSG_*) /* 24 bits available here */ uint32_t flags; // H1 message flags (H1_MF_*) uint64_t curr_len; // content-length or last chunk length uint64_t body_len; // total known size of the body length uint32_t next; // next byte to parse, relative to buffer's head int err_pos; // position in the byte stream of the first error (H1 or H2) int err_state; // state where the first error was met (H1 or H2) }; /* basic H1 start line, describes either the request and the response */ union h1_sl { /* useful start line pointers, relative to ->sol */ struct { struct ist m; /* METHOD */ struct ist u; /* URI */ struct ist v; /* VERSION */ enum http_meth_t meth; /* method */ } rq; /* request line : field, length */ struct { struct ist v; /* VERSION */ struct ist c; /* CODE */ struct ist r; /* REASON */ uint16_t status; /* status code */ } st; /* status line : field, length */ }; int h1_headers_to_hdr_list(char *start, const char *stop, struct http_hdr *hdr, unsigned int hdr_num, struct h1m *h1m, union h1_sl *slp); int h1_measure_trailers(const struct buffer *buf, unsigned int ofs, unsigned int max); int h1_parse_cont_len_header(struct h1m *h1m, struct ist *value); void h1_parse_xfer_enc_header(struct h1m *h1m, struct ist value); void h1_parse_connection_header(struct h1m *h1m, struct ist *value); /* for debugging, reports the HTTP/1 message state name */ static inline const char *h1m_state_str(enum h1m_state msg_state) { switch (msg_state) { case H1_MSG_RQBEFORE: return "MSG_RQBEFORE"; case H1_MSG_RQBEFORE_CR: return "MSG_RQBEFORE_CR"; case H1_MSG_RQMETH: return "MSG_RQMETH"; case H1_MSG_RQMETH_SP: return "MSG_RQMETH_SP"; case H1_MSG_RQURI: return "MSG_RQURI"; case H1_MSG_RQURI_SP: return "MSG_RQURI_SP"; case H1_MSG_RQVER: return "MSG_RQVER"; case H1_MSG_RQLINE_END: return "MSG_RQLINE_END"; case H1_MSG_RPBEFORE: return "MSG_RPBEFORE"; case H1_MSG_RPBEFORE_CR: return "MSG_RPBEFORE_CR"; case H1_MSG_RPVER: return "MSG_RPVER"; case H1_MSG_RPVER_SP: return "MSG_RPVER_SP"; case H1_MSG_RPCODE: return "MSG_RPCODE"; case H1_MSG_RPCODE_SP: return "MSG_RPCODE_SP"; case H1_MSG_RPREASON: return "MSG_RPREASON"; case H1_MSG_RPLINE_END: return "MSG_RPLINE_END"; case H1_MSG_HDR_FIRST: return "MSG_HDR_FIRST"; case H1_MSG_HDR_NAME: return "MSG_HDR_NAME"; case H1_MSG_HDR_COL: return "MSG_HDR_COL"; case H1_MSG_HDR_L1_SP: return "MSG_HDR_L1_SP"; case H1_MSG_HDR_L1_LF: return "MSG_HDR_L1_LF"; case H1_MSG_HDR_L1_LWS: return "MSG_HDR_L1_LWS"; case H1_MSG_HDR_VAL: return "MSG_HDR_VAL"; case H1_MSG_HDR_L2_LF: return "MSG_HDR_L2_LF"; case H1_MSG_HDR_L2_LWS: return "MSG_HDR_L2_LWS"; case H1_MSG_LAST_LF: return "MSG_LAST_LF"; case H1_MSG_CHUNK_SIZE: return "MSG_CHUNK_SIZE"; case H1_MSG_DATA: return "MSG_DATA"; case H1_MSG_CHUNK_CRLF: return "MSG_CHUNK_CRLF"; case H1_MSG_TRAILERS: return "MSG_TRAILERS"; case H1_MSG_DONE: return "MSG_DONE"; case H1_MSG_TUNNEL: return "MSG_TUNNEL"; default: return "MSG_??????"; } } /* This function may be called only in HTTP_MSG_CHUNK_CRLF. It reads the CRLF or * a possible LF alone at the end of a chunk. The caller should adjust msg->next * in order to include this part into the next forwarding phase. Note that the * caller must ensure that head+start points to the first byte to parse. It * returns the number of bytes parsed on success, so the caller can set msg_state * to HTTP_MSG_CHUNK_SIZE. If not enough data are available, the function does not * change anything and returns zero. Otherwise it returns a negative value * indicating the error position relative to . Note: this function is * designed to parse wrapped CRLF at the end of the buffer. */ static inline int h1_skip_chunk_crlf(const struct buffer *buf, int start, int stop) { const char *ptr = b_peek(buf, start); int bytes = 1; if (stop <= start) return 0; /* NB: we'll check data availability at the end. It's not a * problem because whatever we match first will be checked * against the correct length. */ if (*ptr == '\r') { bytes++; ptr++; if (ptr >= b_wrap(buf)) ptr = b_orig(buf); } if (bytes > stop - start) return 0; if (*ptr != '\n') // negative position to stop return ptr - __b_peek(buf, stop); return bytes; } /* Parse the chunk size start at buf + start and stops before buf + stop. The * positions are relative to the buffer's head. * It returns the chunk size in and the amount of bytes read this way : * < 0 : error at this position relative to * = 0 : not enough bytes to read a complete chunk size * > 0 : number of bytes successfully read that the caller can skip * On success, the caller should adjust its msg->next to point to the first * byte of data after the chunk size, so that we know we can forward exactly * msg->next bytes, and msg->sol to contain the exact number of bytes forming * the chunk size. That way it is always possible to differentiate between the * start of the body and the start of the data. Note: this function is designed * to parse wrapped CRLF at the end of the buffer. */ static inline int h1_parse_chunk_size(const struct buffer *buf, int start, int stop, unsigned int *res) { const char *ptr = b_peek(buf, start); const char *ptr_old = ptr; const char *end = b_wrap(buf); unsigned int chunk = 0; stop -= start; // bytes left start = stop; // bytes to transfer /* The chunk size is in the following form, though we are only * interested in the size and CRLF : * 1*HEXDIGIT *WSP *[ ';' extensions ] CRLF */ while (1) { int c; if (!stop) return 0; c = hex2i(*ptr); if (c < 0) /* not a hex digit anymore */ break; if (unlikely(++ptr >= end)) ptr = b_orig(buf); if (unlikely(chunk & 0xF8000000)) /* integer overflow will occur if result >= 2GB */ goto error; chunk = (chunk << 4) + c; stop--; } /* empty size not allowed */ if (unlikely(ptr == ptr_old)) goto error; while (HTTP_IS_SPHT(*ptr)) { if (++ptr >= end) ptr = b_orig(buf); if (--stop == 0) return 0; } /* Up to there, we know that at least one byte is present at *ptr. Check * for the end of chunk size. */ while (1) { if (likely(HTTP_IS_CRLF(*ptr))) { /* we now have a CR or an LF at ptr */ if (likely(*ptr == '\r')) { if (++ptr >= end) ptr = b_orig(buf); if (--stop == 0) return 0; } if (*ptr != '\n') goto error; if (++ptr >= end) ptr = b_orig(buf); --stop; /* done */ break; } else if (likely(*ptr == ';')) { /* chunk extension, ends at next CRLF */ if (++ptr >= end) ptr = b_orig(buf); if (--stop == 0) return 0; while (!HTTP_IS_CRLF(*ptr)) { if (++ptr >= end) ptr = b_orig(buf); if (--stop == 0) return 0; } /* we have a CRLF now, loop above */ continue; } else goto error; } /* OK we found our CRLF and now points to the next byte, which may * or may not be present. Let's return the number of bytes parsed. */ *res = chunk; return start - stop; error: *res = 0; // just to stop gcc's -Wuninitialized warning :-( return -stop; } /* initializes an H1 message for a request */ static inline struct h1m *h1m_init_req(struct h1m *h1m) { h1m->state = H1_MSG_RQBEFORE; h1m->next = 0; h1m->flags = H1_MF_NONE; h1m->curr_len = 0; h1m->body_len = 0; h1m->err_pos = -2; h1m->err_state = 0; return h1m; } /* initializes an H1 message for a response */ static inline struct h1m *h1m_init_res(struct h1m *h1m) { h1m->state = H1_MSG_RPBEFORE; h1m->next = 0; h1m->flags = H1_MF_RESP; h1m->curr_len = 0; h1m->body_len = 0; h1m->err_pos = -2; h1m->err_state = 0; return h1m; } #endif /* _HAPROXY_H1_H */