diff options
Diffstat (limited to 'src/fcgi.c')
-rw-r--r-- | src/fcgi.c | 294 |
1 files changed, 294 insertions, 0 deletions
diff --git a/src/fcgi.c b/src/fcgi.c new file mode 100644 index 0000000..1d1a82b --- /dev/null +++ b/src/fcgi.c @@ -0,0 +1,294 @@ +/* + * FastCGI protocol processing + * + * Copyright (C) 2019 HAProxy Technologies, Christopher Faulet <cfaulet@haproxy.com> + * + * 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 <haproxy/buf.h> +#include <haproxy/fcgi.h> +#include <haproxy/istbuf.h> + +/* Encodes header of a FCGI record into the chunk <out>. It returns non-zero on + * success and 0 on failure (buffer full). <out> is a chunk, so the wrapping is + * not handled by this function. It is the caller responsibility to ensure + * enough contiguous space is available + */ +int fcgi_encode_record_hdr(struct buffer *out, const struct fcgi_header *h) +{ + size_t len = out->data; + + if (len + 8 >= b_size(out)) + return 0; + + out->area[len++] = h->vsn; + out->area[len++] = h->type; + out->area[len++] = ((h->id >> 8) & 0xff); + out->area[len++] = (h->id & 0xff); + out->area[len++] = ((h->len >> 8) & 0xff); + out->area[len++] = (h->len & 0xff); + out->area[len++] = h->padding; + out->area[len++] = 0; /* rsv */ + + out->data = len; + return 1; +} + +/* Decodes a FCGI record header from offset <o> of buffer <in> into descriptor + * <h>. The buffer may wrap so each byte read must be checked. The header is + * formed like this : + * + * b0 b1 b2 b3 b4 b5 b6 b7 + * +-----+------+-----+-----+------+------+--------+-----+ + * | vsn | type | id1 | id0 | len1 | len0 | padlen | rsv | + * +-----+------+-----+-----+------+------+--------+-----+ + * + * Returns zero if some bytes are missing, otherwise the number of read bytes. + */ +size_t fcgi_decode_record_hdr(const struct buffer *in, size_t o, struct fcgi_header *h) +{ + if (b_data(in) < o + 8) + return 0; + + h->vsn = (uint8_t)(*b_peek(in, o)); + h->type = (uint8_t)(*b_peek(in, o+1)); + h->id = ((uint8_t)(*b_peek(in, o+2)) << 8) + (uint8_t)(*b_peek(in, o+3)); + h->len = ((uint8_t)(*b_peek(in, o+4)) << 8) + (uint8_t)(*b_peek(in, o+5)); + h->padding = (uint8_t)(*b_peek(in, o+6)); + /* ignore rsv */ + + return 8; +} + +/* Encodes the payload part of a BEGIN_REQUEST record into the chunk <out>. It + * returns non-zero on success and 0 on failure (buffer full). <out> is a chunk, + * so the wrapping is not handled by this function. It is the caller + * responsibility to ensure enough contiguous space is available + */ +int fcgi_encode_begin_request(struct buffer *out, const struct fcgi_begin_request *r) +{ + size_t len = out->data; + + if (len + 8 >= b_size(out)) + return 0; + + out->area[len++] = ((r->role >> 8) & 0xff); + out->area[len++] = (r->role & 0xff); + out->area[len++] = r->flags; + out->area[len++] = 0; /* rsv */ + out->area[len++] = 0; + out->area[len++] = 0; + out->area[len++] = 0; + out->area[len++] = 0; + + out->data = len; + return 1; +} + +/* Encodes a parameter, part of the payload of a PARAM record, into the chunk + * <out>. It returns non-zero on success and 0 on failure (buffer full). <out> + * is a chunk, so the wrapping is not handled by this function. It is the caller + * responsibility to ensure enough contiguous space is available. The + * parameter's name is converted to upper case and non-alphanumeric character + * are replaced by an underscore. + */ +int fcgi_encode_param(struct buffer *out, const struct fcgi_param *p) +{ + size_t off, len = out->data; + int nbytes, vbytes; + + nbytes = (!(p->n.len >> 7) ? 1 : 4); + vbytes = (!(p->v.len >> 7) ? 1 : 4); + if ((len + nbytes + p->n.len + vbytes + p->v.len) >= b_size(out)) + return 0; + + if (nbytes == 1) + out->area[len++] = (p->n.len & 0xff); + else { + out->area[len++] = (((p->n.len >> 24) & 0xff) | 0x80); + out->area[len++] = ((p->n.len >> 16) & 0xff); + out->area[len++] = ((p->n.len >> 8) & 0xff); + out->area[len++] = (p->n.len & 0xff); + } + + if (vbytes == 1) + out->area[len++] = (p->v.len & 0xff); + else { + out->area[len++] = (((p->v.len >> 24) & 0xff) | 0x80); + out->area[len++] = ((p->v.len >> 16) & 0xff); + out->area[len++] = ((p->v.len >> 8) & 0xff); + out->area[len++] = (p->v.len & 0xff); + } + + for (off = 0; off < p->n.len; off++) { + if (isalnum((unsigned char)p->n.ptr[off])) + out->area[len++] = ist_uc[(unsigned char)p->n.ptr[off]]; + else + out->area[len++] = '_'; + } + if (p->v.len) { + ist2bin(out->area + len, p->v); + len += p->v.len; + } + + out->data = len; + return 1; +} + +/* Decodes a parameter of a PARAM record from offset <o> of buffer <in> into the + * FCGI param <p>. The buffer may wrap so each byte read must be checked. + * Returns zero if some bytes are missing, otherwise the number of read bytes. + */ +size_t fcgi_decode_param(const struct buffer *in, size_t o, struct fcgi_param *p) +{ + size_t data = b_data(in); + size_t nlen, vlen, len = 0; + uint8_t b0, b1, b2, b3; + + if (data < o + 1) + return 0; + b0 = *b_peek(in, o++); + if (!(b0 >> 7)) { + nlen = b0; + len++; + } + else { + if (data < o + 3) + return 0; + b1 = *b_peek(in, o++); + b2 = *b_peek(in, o++); + b3 = *b_peek(in, o++); + nlen = ((b0 & 0x7f) << 24) + (b1 << 16) + (b2 << 8) + b3; + len += 4; + } + + if (data < o + 1) + return 0; + b0 = *b_peek(in, o++); + if (!(b0 >> 7)) { + vlen = b0; + len++; + } + else { + if (data < o + 3) + return 0; + b1 = *b_peek(in, o++); + b2 = *b_peek(in, o++); + b3 = *b_peek(in, o++); + vlen = ((b0 & 0x7f) << 24) + (b1 << 16) + (b2 << 8) + b3; + len += 4; + } + + if (data < nlen + vlen) + return 0; + + p->n = ist2(b_peek(in, o), nlen); + p->v = ist2(b_peek(in, o + nlen), vlen); + len += nlen + vlen; + + return len; +} + + +/* Decodes a parameter of a PARAM record from offset <o> of buffer <in> into the + * FCGI param <p>. To call this function, the buffer must not wrap. Returns zero + * if some bytes are missing, otherwise the number of read bytes. + */ +size_t fcgi_aligned_decode_param(const struct buffer *in, size_t o, struct fcgi_param *p) +{ + size_t data = b_data(in); + size_t nlen, vlen, len = 0; + uint8_t b0, b1, b2, b3; + + if (data < o + 1) + return 0; + b0 = in->area[o++]; + if (!(b0 >> 7)) { + nlen = b0; + len++; + } + else { + if (data < o + 3) + return 0; + b1 = in->area[o++]; + b2 = in->area[o++]; + b3 = in->area[o++]; + nlen = ((b0 & 0x7f) << 24) + (b1 << 16) + (b2 << 8) + b3; + len += 4; + } + + if (data < o + 1) + return 0; + b0 = in->area[o++]; + if (!(b0 >> 7)) { + vlen = b0; + len++; + } + else { + if (data < o + 3) + return 0; + b1 = in->area[o++]; + b2 = in->area[o++]; + b3 = in->area[o++]; + vlen = ((b0 & 0x7f) << 24) + (b1 << 16) + (b2 << 8) + b3; + len += 4; + } + + if (data < nlen + vlen) + return 0; + + p->n = ist2(in->area + o, nlen); + p->v = ist2(in->area + o + nlen, vlen); + len += nlen + vlen; + + return len; +} + +/* Decodes payload of a END_REQUEST record from offset <o> of buffer <in> into + * the FCGI param <p>. The buffer may wrap so each byte read must be + * checked. Returns zero if some bytes are missing, otherwise the number of read + * bytes. + */ +size_t fcgi_decode_end_request(const struct buffer *in, size_t o, struct fcgi_end_request *rec) +{ + uint8_t b0, b1, b2, b3; + + if (b_data(in) < o + 8) + return 0; + + b0 = *b_peek(in, o++); + b1 = *b_peek(in, o++); + b2 = *b_peek(in, o++); + b3 = *b_peek(in, o++); + rec->status = ((b0 & 0x7f) << 24) + (b1 << 16) + (b2 << 8) + b3; + rec->errcode = *b_peek(in, o++); + o += 3; /* ignore rsv */ + + return 8; +} + +/* + * Local variables: + * c-indent-level: 8 + * c-basic-offset: 8 + * End: + */ |