/* * include/haproxy/spoe.h * Encoding/Decoding functions for the SPOE filters (and other helpers). * * Copyright (C) 2017 HAProxy Technologies, Christopher Faulet * * 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_SPOE_H #define _HAPROXY_SPOE_H #include #include #include #include /* Encode a buffer. Its length is encoded as a varint, followed by a copy * of . It must have enough space in <*buf> to encode the buffer, else an * error is triggered. * On success, it returns and <*buf> is moved after the encoded value. If * an error occurred, it returns -1. */ static inline int spoe_encode_buffer(const char *str, size_t len, char **buf, char *end) { char *p = *buf; int ret; if (p >= end) return -1; if (!len) { *p++ = 0; *buf = p; return 0; } ret = encode_varint(len, &p, end); if (ret == -1 || p + len > end) return -1; memcpy(p, str, len); *buf = p + len; return len; } /* Encode a buffer, possibly partially. It does the same thing than * 'spoe_encode_buffer', but if there is not enough space, it does not fail. * On success, it returns the number of copied bytes and <*buf> is moved after * the encoded value. If an error occurred, it returns -1. */ static inline int spoe_encode_frag_buffer(const char *str, size_t len, char **buf, char *end) { char *p = *buf; int ret; if (p >= end) return -1; if (!len) { *p++ = 0; *buf = p; return 0; } ret = encode_varint(len, &p, end); if (ret == -1 || p >= end) return -1; ret = (p+len < end) ? len : (end - p); memcpy(p, str, ret); *buf = p + ret; return ret; } /* Decode a buffer. The buffer length is decoded and saved in <*len>. <*str> * points on the first byte of the buffer. * On success, it returns the buffer length and <*buf> is moved after the * encoded buffer. Otherwise, it returns -1. */ static inline int spoe_decode_buffer(char **buf, char *end, char **str, uint64_t *len) { char *p = *buf; uint64_t sz; int ret; *str = NULL; *len = 0; ret = decode_varint(&p, end, &sz); if (ret == -1 || p + sz > end) return -1; *str = p; *len = sz; *buf = p + sz; return sz; } /* Encode a typed data using value in . On success, it returns the number * of copied bytes and <*buf> is moved after the encoded value. If an error * occurred, it returns -1. * * If the value is too big to be encoded, depending on its type, then encoding * failed or the value is partially encoded. Only strings and binaries can be * partially encoded. */ static inline int spoe_encode_data(struct sample *smp, char **buf, char *end) { char *p = *buf; int ret; if (p >= end) return -1; if (smp == NULL) { *p++ = SPOE_DATA_T_NULL; goto end; } switch (smp->data.type) { case SMP_T_BOOL: *p = SPOE_DATA_T_BOOL; *p++ |= ((!smp->data.u.sint) ? SPOE_DATA_FL_FALSE : SPOE_DATA_FL_TRUE); break; case SMP_T_SINT: *p++ = SPOE_DATA_T_INT64; if (encode_varint(smp->data.u.sint, &p, end) == -1) return -1; break; case SMP_T_IPV4: if (p + 5 > end) return -1; *p++ = SPOE_DATA_T_IPV4; memcpy(p, &smp->data.u.ipv4, 4); p += 4; break; case SMP_T_IPV6: if (p + 17 > end) return -1; *p++ = SPOE_DATA_T_IPV6; memcpy(p, &smp->data.u.ipv6, 16); p += 16; break; case SMP_T_STR: case SMP_T_BIN: { /* If defined, get length and offset of the sample by reading the sample * context. ctx.a[0] is the pointer to the length and ctx.a[1] is the * pointer to the offset. If the offset is greater than 0, it means the * sample is partially encoded. In this case, we only need to encode the * reamining. When all the sample is encoded, the offset is reset to 0. * So the caller know it can try to encode the next sample. */ struct buffer *chk = &smp->data.u.str; unsigned int *len = smp->ctx.a[0]; unsigned int *off = smp->ctx.a[1]; if (!*off) { /* First evaluation of the sample : encode the * type (string or binary), the buffer length * (as a varint) and at least 1 byte of the * buffer. */ struct buffer *chk = &smp->data.u.str; *p++ = (smp->data.type == SMP_T_STR) ? SPOE_DATA_T_STR : SPOE_DATA_T_BIN; ret = spoe_encode_frag_buffer(chk->area, chk->data, &p, end); if (ret == -1) return -1; *len = chk->data; } else { /* The sample has been fragmented, encode remaining data */ ret = MIN(*len - *off, end - p); memcpy(p, chk->area + *off, ret); p += ret; } /* Now update <*off> */ if (ret + *off != *len) *off += ret; else *off = 0; break; } case SMP_T_METH: { char *m; size_t len; *p++ = SPOE_DATA_T_STR; switch (smp->data.u.meth.meth) { case HTTP_METH_OPTIONS: m = "OPTIONS"; len = 7; break; case HTTP_METH_GET : m = "GET"; len = 3; break; case HTTP_METH_HEAD : m = "HEAD"; len = 4; break; case HTTP_METH_POST : m = "POST"; len = 4; break; case HTTP_METH_PUT : m = "PUT"; len = 3; break; case HTTP_METH_DELETE : m = "DELETE"; len = 6; break; case HTTP_METH_TRACE : m = "TRACE"; len = 5; break; case HTTP_METH_CONNECT: m = "CONNECT"; len = 7; break; default : m = smp->data.u.meth.str.area; len = smp->data.u.meth.str.data; } if (spoe_encode_buffer(m, len, &p, end) == -1) return -1; break; } default: *p++ = SPOE_DATA_T_NULL; break; } end: ret = (p - *buf); *buf = p; return ret; } /* Skip a typed data. If an error occurred, -1 is returned, otherwise the number * of skipped bytes is returned and the <*buf> is moved after skipped data. * * A types data is composed of a type (1 byte) and corresponding data: * - boolean: non additional data (0 bytes) * - integers: a variable-length integer (see decode_varint) * - ipv4: 4 bytes * - ipv6: 16 bytes * - binary and string: a buffer prefixed by its size, a variable-length * integer (see spoe_decode_buffer) */ static inline int spoe_skip_data(char **buf, char *end) { char *str, *p = *buf; int type, ret; uint64_t v, sz; if (p >= end) return -1; type = *p++; switch (type & SPOE_DATA_T_MASK) { case SPOE_DATA_T_BOOL: break; case SPOE_DATA_T_INT32: case SPOE_DATA_T_INT64: case SPOE_DATA_T_UINT32: case SPOE_DATA_T_UINT64: if (decode_varint(&p, end, &v) == -1) return -1; break; case SPOE_DATA_T_IPV4: if (p+4 > end) return -1; p += 4; break; case SPOE_DATA_T_IPV6: if (p+16 > end) return -1; p += 16; break; case SPOE_DATA_T_STR: case SPOE_DATA_T_BIN: /* All the buffer must be skipped */ if (spoe_decode_buffer(&p, end, &str, &sz) == -1) return -1; break; } ret = (p - *buf); *buf = p; return ret; } /* Decode a typed data and fill . If an error occurred, -1 is returned, * otherwise the number of read bytes is returned and <*buf> is moved after the * decoded data. See spoe_skip_data for details. */ static inline int spoe_decode_data(char **buf, char *end, struct sample *smp) { char *str, *p = *buf; int type, r = 0; uint64_t sz; if (p >= end) return -1; type = *p++; switch (type & SPOE_DATA_T_MASK) { case SPOE_DATA_T_BOOL: smp->data.u.sint = ((type & SPOE_DATA_FL_MASK) == SPOE_DATA_FL_TRUE); smp->data.type = SMP_T_BOOL; break; case SPOE_DATA_T_INT32: case SPOE_DATA_T_INT64: case SPOE_DATA_T_UINT32: case SPOE_DATA_T_UINT64: if (decode_varint(&p, end, (uint64_t *)&smp->data.u.sint) == -1) return -1; smp->data.type = SMP_T_SINT; break; case SPOE_DATA_T_IPV4: if (p+4 > end) return -1; smp->data.type = SMP_T_IPV4; memcpy(&smp->data.u.ipv4, p, 4); p += 4; break; case SPOE_DATA_T_IPV6: if (p+16 > end) return -1; memcpy(&smp->data.u.ipv6, p, 16); smp->data.type = SMP_T_IPV6; p += 16; break; case SPOE_DATA_T_STR: case SPOE_DATA_T_BIN: /* All the buffer must be decoded */ if (spoe_decode_buffer(&p, end, &str, &sz) == -1) return -1; smp->data.u.str.area = str; smp->data.u.str.data = sz; smp->data.type = (type == SPOE_DATA_T_STR) ? SMP_T_STR : SMP_T_BIN; break; } r = (p - *buf); *buf = p; return r; } #endif /* _HAPROXY_SPOE_H */