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Diffstat (limited to 'lwip/src/core/snmp/asn1_dec.c')
| -rw-r--r-- | lwip/src/core/snmp/asn1_dec.c | 657 |
1 files changed, 0 insertions, 657 deletions
diff --git a/lwip/src/core/snmp/asn1_dec.c b/lwip/src/core/snmp/asn1_dec.c deleted file mode 100644 index 1d56582..0000000 --- a/lwip/src/core/snmp/asn1_dec.c +++ /dev/null @@ -1,657 +0,0 @@ -/** - * @file - * Abstract Syntax Notation One (ISO 8824, 8825) decoding - * - * @todo not optimised (yet), favor correctness over speed, favor speed over size - */ - -/* - * Copyright (c) 2006 Axon Digital Design B.V., The Netherlands. - * All rights reserved. - * - * 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. - * 3. The name of the author may not be used to endorse or promote products - * derived from this software without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 THE AUTHOR 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. - * - * Author: Christiaan Simons <christiaan.simons@axon.tv> - */ - -#include "lwip/opt.h" - -#if LWIP_SNMP /* don't build if not configured for use in lwipopts.h */ - -#include "lwip/snmp_asn1.h" - -/** - * Retrieves type field from incoming pbuf chain. - * - * @param p points to a pbuf holding an ASN1 coded type field - * @param ofs points to the offset within the pbuf chain of the ASN1 coded type field - * @param type return ASN1 type - * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) decode - */ -err_t -snmp_asn1_dec_type(struct pbuf *p, u16_t ofs, u8_t *type) -{ - u16_t plen, base; - u8_t *msg_ptr; - - plen = 0; - while (p != NULL) - { - base = plen; - plen += p->len; - if (ofs < plen) - { - msg_ptr = (u8_t*)p->payload; - msg_ptr += ofs - base; - *type = *msg_ptr; - return ERR_OK; - } - p = p->next; - } - /* p == NULL, ofs >= plen */ - return ERR_ARG; -} - -/** - * Decodes length field from incoming pbuf chain into host length. - * - * @param p points to a pbuf holding an ASN1 coded length - * @param ofs points to the offset within the pbuf chain of the ASN1 coded length - * @param octets_used returns number of octets used by the length code - * @param length return host order length, upto 64k - * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) decode - */ -err_t -snmp_asn1_dec_length(struct pbuf *p, u16_t ofs, u8_t *octets_used, u16_t *length) -{ - u16_t plen, base; - u8_t *msg_ptr; - - plen = 0; - while (p != NULL) - { - base = plen; - plen += p->len; - if (ofs < plen) - { - msg_ptr = (u8_t*)p->payload; - msg_ptr += ofs - base; - - if (*msg_ptr < 0x80) - { - /* primitive definite length format */ - *octets_used = 1; - *length = *msg_ptr; - return ERR_OK; - } - else if (*msg_ptr == 0x80) - { - /* constructed indefinite length format, termination with two zero octets */ - u8_t zeros; - u8_t i; - - *length = 0; - zeros = 0; - while (zeros != 2) - { - i = 2; - while (i > 0) - { - i--; - (*length) += 1; - ofs += 1; - if (ofs >= plen) - { - /* next octet in next pbuf */ - p = p->next; - if (p == NULL) { return ERR_ARG; } - msg_ptr = (u8_t*)p->payload; - plen += p->len; - } - else - { - /* next octet in same pbuf */ - msg_ptr++; - } - if (*msg_ptr == 0) - { - zeros++; - if (zeros == 2) - { - /* stop while (i > 0) */ - i = 0; - } - } - else - { - zeros = 0; - } - } - } - *octets_used = 1; - return ERR_OK; - } - else if (*msg_ptr == 0x81) - { - /* constructed definite length format, one octet */ - ofs += 1; - if (ofs >= plen) - { - /* next octet in next pbuf */ - p = p->next; - if (p == NULL) { return ERR_ARG; } - msg_ptr = (u8_t*)p->payload; - } - else - { - /* next octet in same pbuf */ - msg_ptr++; - } - *length = *msg_ptr; - *octets_used = 2; - return ERR_OK; - } - else if (*msg_ptr == 0x82) - { - u8_t i; - - /* constructed definite length format, two octets */ - i = 2; - while (i > 0) - { - i--; - ofs += 1; - if (ofs >= plen) - { - /* next octet in next pbuf */ - p = p->next; - if (p == NULL) { return ERR_ARG; } - msg_ptr = (u8_t*)p->payload; - plen += p->len; - } - else - { - /* next octet in same pbuf */ - msg_ptr++; - } - if (i == 0) - { - /* least significant length octet */ - *length |= *msg_ptr; - } - else - { - /* most significant length octet */ - *length = (*msg_ptr) << 8; - } - } - *octets_used = 3; - return ERR_OK; - } - else - { - /* constructed definite length format 3..127 octets, this is too big (>64k) */ - /** @todo: do we need to accept inefficient codings with many leading zero's? */ - *octets_used = 1 + ((*msg_ptr) & 0x7f); - return ERR_ARG; - } - } - p = p->next; - } - - /* p == NULL, ofs >= plen */ - return ERR_ARG; -} - -/** - * Decodes positive integer (counter, gauge, timeticks) into u32_t. - * - * @param p points to a pbuf holding an ASN1 coded integer - * @param ofs points to the offset within the pbuf chain of the ASN1 coded integer - * @param len length of the coded integer field - * @param value return host order integer - * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) decode - * - * @note ASN coded integers are _always_ signed. E.g. +0xFFFF is coded - * as 0x00,0xFF,0xFF. Note the leading sign octet. A positive value - * of 0xFFFFFFFF is preceded with 0x00 and the length is 5 octets!! - */ -err_t -snmp_asn1_dec_u32t(struct pbuf *p, u16_t ofs, u16_t len, u32_t *value) -{ - u16_t plen, base; - u8_t *msg_ptr; - - plen = 0; - while (p != NULL) - { - base = plen; - plen += p->len; - if (ofs < plen) - { - msg_ptr = (u8_t*)p->payload; - msg_ptr += ofs - base; - if ((len > 0) && (len < 6)) - { - /* start from zero */ - *value = 0; - if (*msg_ptr & 0x80) - { - /* negative, expecting zero sign bit! */ - return ERR_ARG; - } - else - { - /* positive */ - if ((len > 1) && (*msg_ptr == 0)) - { - /* skip leading "sign byte" octet 0x00 */ - len--; - ofs += 1; - if (ofs >= plen) - { - /* next octet in next pbuf */ - p = p->next; - if (p == NULL) { return ERR_ARG; } - msg_ptr = (u8_t*)p->payload; - plen += p->len; - } - else - { - /* next octet in same pbuf */ - msg_ptr++; - } - } - } - /* OR octets with value */ - while (len > 1) - { - len--; - *value |= *msg_ptr; - *value <<= 8; - ofs += 1; - if (ofs >= plen) - { - /* next octet in next pbuf */ - p = p->next; - if (p == NULL) { return ERR_ARG; } - msg_ptr = (u8_t*)p->payload; - plen += p->len; - } - else - { - /* next octet in same pbuf */ - msg_ptr++; - } - } - *value |= *msg_ptr; - return ERR_OK; - } - else - { - return ERR_ARG; - } - } - p = p->next; - } - /* p == NULL, ofs >= plen */ - return ERR_ARG; -} - -/** - * Decodes integer into s32_t. - * - * @param p points to a pbuf holding an ASN1 coded integer - * @param ofs points to the offset within the pbuf chain of the ASN1 coded integer - * @param len length of the coded integer field - * @param value return host order integer - * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) decode - * - * @note ASN coded integers are _always_ signed! - */ -err_t -snmp_asn1_dec_s32t(struct pbuf *p, u16_t ofs, u16_t len, s32_t *value) -{ - u16_t plen, base; - u8_t *msg_ptr; -#if BYTE_ORDER == LITTLE_ENDIAN - u8_t *lsb_ptr = (u8_t*)value; -#endif -#if BYTE_ORDER == BIG_ENDIAN - u8_t *lsb_ptr = (u8_t*)value + sizeof(s32_t) - 1; -#endif - u8_t sign; - - plen = 0; - while (p != NULL) - { - base = plen; - plen += p->len; - if (ofs < plen) - { - msg_ptr = (u8_t*)p->payload; - msg_ptr += ofs - base; - if ((len > 0) && (len < 5)) - { - if (*msg_ptr & 0x80) - { - /* negative, start from -1 */ - *value = -1; - sign = 1; - } - else - { - /* positive, start from 0 */ - *value = 0; - sign = 0; - } - /* OR/AND octets with value */ - while (len > 1) - { - len--; - if (sign) - { - *lsb_ptr &= *msg_ptr; - *value <<= 8; - *lsb_ptr |= 255; - } - else - { - *lsb_ptr |= *msg_ptr; - *value <<= 8; - } - ofs += 1; - if (ofs >= plen) - { - /* next octet in next pbuf */ - p = p->next; - if (p == NULL) { return ERR_ARG; } - msg_ptr = (u8_t*)p->payload; - plen += p->len; - } - else - { - /* next octet in same pbuf */ - msg_ptr++; - } - } - if (sign) - { - *lsb_ptr &= *msg_ptr; - } - else - { - *lsb_ptr |= *msg_ptr; - } - return ERR_OK; - } - else - { - return ERR_ARG; - } - } - p = p->next; - } - /* p == NULL, ofs >= plen */ - return ERR_ARG; -} - -/** - * Decodes object identifier from incoming message into array of s32_t. - * - * @param p points to a pbuf holding an ASN1 coded object identifier - * @param ofs points to the offset within the pbuf chain of the ASN1 coded object identifier - * @param len length of the coded object identifier - * @param oid return object identifier struct - * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) decode - */ -err_t -snmp_asn1_dec_oid(struct pbuf *p, u16_t ofs, u16_t len, struct snmp_obj_id *oid) -{ - u16_t plen, base; - u8_t *msg_ptr; - s32_t *oid_ptr; - - plen = 0; - while (p != NULL) - { - base = plen; - plen += p->len; - if (ofs < plen) - { - msg_ptr = (u8_t*)p->payload; - msg_ptr += ofs - base; - - oid->len = 0; - oid_ptr = &oid->id[0]; - if (len > 0) - { - /* first compressed octet */ - if (*msg_ptr == 0x2B) - { - /* (most) common case 1.3 (iso.org) */ - *oid_ptr = 1; - oid_ptr++; - *oid_ptr = 3; - oid_ptr++; - } - else if (*msg_ptr < 40) - { - *oid_ptr = 0; - oid_ptr++; - *oid_ptr = *msg_ptr; - oid_ptr++; - } - else if (*msg_ptr < 80) - { - *oid_ptr = 1; - oid_ptr++; - *oid_ptr = (*msg_ptr) - 40; - oid_ptr++; - } - else - { - *oid_ptr = 2; - oid_ptr++; - *oid_ptr = (*msg_ptr) - 80; - oid_ptr++; - } - oid->len = 2; - } - else - { - /* accepting zero length identifiers e.g. for - getnext operation. uncommon but valid */ - return ERR_OK; - } - len--; - if (len > 0) - { - ofs += 1; - if (ofs >= plen) - { - /* next octet in next pbuf */ - p = p->next; - if (p == NULL) { return ERR_ARG; } - msg_ptr = (u8_t*)p->payload; - plen += p->len; - } - else - { - /* next octet in same pbuf */ - msg_ptr++; - } - } - while ((len > 0) && (oid->len < LWIP_SNMP_OBJ_ID_LEN)) - { - /* sub-identifier uses multiple octets */ - if (*msg_ptr & 0x80) - { - s32_t sub_id = 0; - - while ((*msg_ptr & 0x80) && (len > 1)) - { - len--; - sub_id = (sub_id << 7) + (*msg_ptr & ~0x80); - ofs += 1; - if (ofs >= plen) - { - /* next octet in next pbuf */ - p = p->next; - if (p == NULL) { return ERR_ARG; } - msg_ptr = (u8_t*)p->payload; - plen += p->len; - } - else - { - /* next octet in same pbuf */ - msg_ptr++; - } - } - if (!(*msg_ptr & 0x80) && (len > 0)) - { - /* last octet sub-identifier */ - len--; - sub_id = (sub_id << 7) + *msg_ptr; - *oid_ptr = sub_id; - } - } - else - { - /* !(*msg_ptr & 0x80) sub-identifier uses single octet */ - len--; - *oid_ptr = *msg_ptr; - } - if (len > 0) - { - /* remaining oid bytes available ... */ - ofs += 1; - if (ofs >= plen) - { - /* next octet in next pbuf */ - p = p->next; - if (p == NULL) { return ERR_ARG; } - msg_ptr = (u8_t*)p->payload; - plen += p->len; - } - else - { - /* next octet in same pbuf */ - msg_ptr++; - } - } - oid_ptr++; - oid->len++; - } - if (len == 0) - { - /* len == 0, end of oid */ - return ERR_OK; - } - else - { - /* len > 0, oid->len == LWIP_SNMP_OBJ_ID_LEN or malformed encoding */ - return ERR_ARG; - } - - } - p = p->next; - } - /* p == NULL, ofs >= plen */ - return ERR_ARG; -} - -/** - * Decodes (copies) raw data (ip-addresses, octet strings, opaque encoding) - * from incoming message into array. - * - * @param p points to a pbuf holding an ASN1 coded raw data - * @param ofs points to the offset within the pbuf chain of the ASN1 coded raw data - * @param len length of the coded raw data (zero is valid, e.g. empty string!) - * @param raw_len length of the raw return value - * @param raw return raw bytes - * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) decode - */ -err_t -snmp_asn1_dec_raw(struct pbuf *p, u16_t ofs, u16_t len, u16_t raw_len, u8_t *raw) -{ - u16_t plen, base; - u8_t *msg_ptr; - - if (len > 0) - { - plen = 0; - while (p != NULL) - { - base = plen; - plen += p->len; - if (ofs < plen) - { - msg_ptr = (u8_t*)p->payload; - msg_ptr += ofs - base; - if (raw_len >= len) - { - while (len > 1) - { - /* copy len - 1 octets */ - len--; - *raw = *msg_ptr; - raw++; - ofs += 1; - if (ofs >= plen) - { - /* next octet in next pbuf */ - p = p->next; - if (p == NULL) { return ERR_ARG; } - msg_ptr = (u8_t*)p->payload; - plen += p->len; - } - else - { - /* next octet in same pbuf */ - msg_ptr++; - } - } - /* copy last octet */ - *raw = *msg_ptr; - return ERR_OK; - } - else - { - /* raw_len < len, not enough dst space */ - return ERR_ARG; - } - } - p = p->next; - } - /* p == NULL, ofs >= plen */ - return ERR_ARG; - } - else - { - /* len == 0, empty string */ - return ERR_OK; - } -} - -#endif /* LWIP_SNMP */ |