/* * Copyright 2015-2018 The OpenSSL Project Authors. All Rights Reserved. * * Licensed under the OpenSSL license (the "License"). You may not use * this file except in compliance with the License. You can obtain a copy * in the file LICENSE in the source distribution or at * https://www.openssl.org/source/license.html */ #include "internal/cryptlib.h" #include "packet_local.h" #include <openssl/sslerr.h> #define DEFAULT_BUF_SIZE 256 int WPACKET_allocate_bytes(WPACKET *pkt, size_t len, unsigned char **allocbytes) { if (!WPACKET_reserve_bytes(pkt, len, allocbytes)) return 0; pkt->written += len; pkt->curr += len; return 1; } int WPACKET_sub_allocate_bytes__(WPACKET *pkt, size_t len, unsigned char **allocbytes, size_t lenbytes) { if (!WPACKET_start_sub_packet_len__(pkt, lenbytes) || !WPACKET_allocate_bytes(pkt, len, allocbytes) || !WPACKET_close(pkt)) return 0; return 1; } #define GETBUF(p) (((p)->staticbuf != NULL) \ ? (p)->staticbuf : (unsigned char *)(p)->buf->data) int WPACKET_reserve_bytes(WPACKET *pkt, size_t len, unsigned char **allocbytes) { /* Internal API, so should not fail */ if (!ossl_assert(pkt->subs != NULL && len != 0)) return 0; if (pkt->maxsize - pkt->written < len) return 0; if (pkt->staticbuf == NULL && (pkt->buf->length - pkt->written < len)) { size_t newlen; size_t reflen; reflen = (len > pkt->buf->length) ? len : pkt->buf->length; if (reflen > SIZE_MAX / 2) { newlen = SIZE_MAX; } else { newlen = reflen * 2; if (newlen < DEFAULT_BUF_SIZE) newlen = DEFAULT_BUF_SIZE; } if (BUF_MEM_grow(pkt->buf, newlen) == 0) return 0; } if (allocbytes != NULL) *allocbytes = WPACKET_get_curr(pkt); return 1; } int WPACKET_sub_reserve_bytes__(WPACKET *pkt, size_t len, unsigned char **allocbytes, size_t lenbytes) { if (!WPACKET_reserve_bytes(pkt, lenbytes + len, allocbytes)) return 0; *allocbytes += lenbytes; return 1; } static size_t maxmaxsize(size_t lenbytes) { if (lenbytes >= sizeof(size_t) || lenbytes == 0) return SIZE_MAX; return ((size_t)1 << (lenbytes * 8)) - 1 + lenbytes; } static int wpacket_intern_init_len(WPACKET *pkt, size_t lenbytes) { unsigned char *lenchars; pkt->curr = 0; pkt->written = 0; if ((pkt->subs = OPENSSL_zalloc(sizeof(*pkt->subs))) == NULL) { SSLerr(SSL_F_WPACKET_INTERN_INIT_LEN, ERR_R_MALLOC_FAILURE); return 0; } if (lenbytes == 0) return 1; pkt->subs->pwritten = lenbytes; pkt->subs->lenbytes = lenbytes; if (!WPACKET_allocate_bytes(pkt, lenbytes, &lenchars)) { OPENSSL_free(pkt->subs); pkt->subs = NULL; return 0; } pkt->subs->packet_len = lenchars - GETBUF(pkt); return 1; } int WPACKET_init_static_len(WPACKET *pkt, unsigned char *buf, size_t len, size_t lenbytes) { size_t max = maxmaxsize(lenbytes); /* Internal API, so should not fail */ if (!ossl_assert(buf != NULL && len > 0)) return 0; pkt->staticbuf = buf; pkt->buf = NULL; pkt->maxsize = (max < len) ? max : len; return wpacket_intern_init_len(pkt, lenbytes); } int WPACKET_init_len(WPACKET *pkt, BUF_MEM *buf, size_t lenbytes) { /* Internal API, so should not fail */ if (!ossl_assert(buf != NULL)) return 0; pkt->staticbuf = NULL; pkt->buf = buf; pkt->maxsize = maxmaxsize(lenbytes); return wpacket_intern_init_len(pkt, lenbytes); } int WPACKET_init(WPACKET *pkt, BUF_MEM *buf) { return WPACKET_init_len(pkt, buf, 0); } int WPACKET_set_flags(WPACKET *pkt, unsigned int flags) { /* Internal API, so should not fail */ if (!ossl_assert(pkt->subs != NULL)) return 0; pkt->subs->flags = flags; return 1; } /* Store the |value| of length |len| at location |data| */ static int put_value(unsigned char *data, size_t value, size_t len) { for (data += len - 1; len > 0; len--) { *data = (unsigned char)(value & 0xff); data--; value >>= 8; } /* Check whether we could fit the value in the assigned number of bytes */ if (value > 0) return 0; return 1; } /* * Internal helper function used by WPACKET_close(), WPACKET_finish() and * WPACKET_fill_lengths() to close a sub-packet and write out its length if * necessary. If |doclose| is 0 then it goes through the motions of closing * (i.e. it fills in all the lengths), but doesn't actually close anything. */ static int wpacket_intern_close(WPACKET *pkt, WPACKET_SUB *sub, int doclose) { size_t packlen = pkt->written - sub->pwritten; if (packlen == 0 && (sub->flags & WPACKET_FLAGS_NON_ZERO_LENGTH) != 0) return 0; if (packlen == 0 && sub->flags & WPACKET_FLAGS_ABANDON_ON_ZERO_LENGTH) { /* We can't handle this case. Return an error */ if (!doclose) return 0; /* Deallocate any bytes allocated for the length of the WPACKET */ if ((pkt->curr - sub->lenbytes) == sub->packet_len) { pkt->written -= sub->lenbytes; pkt->curr -= sub->lenbytes; } /* Don't write out the packet length */ sub->packet_len = 0; sub->lenbytes = 0; } /* Write out the WPACKET length if needed */ if (sub->lenbytes > 0 && !put_value(&GETBUF(pkt)[sub->packet_len], packlen, sub->lenbytes)) return 0; if (doclose) { pkt->subs = sub->parent; OPENSSL_free(sub); } return 1; } int WPACKET_fill_lengths(WPACKET *pkt) { WPACKET_SUB *sub; if (!ossl_assert(pkt->subs != NULL)) return 0; for (sub = pkt->subs; sub != NULL; sub = sub->parent) { if (!wpacket_intern_close(pkt, sub, 0)) return 0; } return 1; } int WPACKET_close(WPACKET *pkt) { /* * Internal API, so should not fail - but we do negative testing of this * so no assert (otherwise the tests fail) */ if (pkt->subs == NULL || pkt->subs->parent == NULL) return 0; return wpacket_intern_close(pkt, pkt->subs, 1); } int WPACKET_finish(WPACKET *pkt) { int ret; /* * Internal API, so should not fail - but we do negative testing of this * so no assert (otherwise the tests fail) */ if (pkt->subs == NULL || pkt->subs->parent != NULL) return 0; ret = wpacket_intern_close(pkt, pkt->subs, 1); if (ret) { OPENSSL_free(pkt->subs); pkt->subs = NULL; } return ret; } int WPACKET_start_sub_packet_len__(WPACKET *pkt, size_t lenbytes) { WPACKET_SUB *sub; unsigned char *lenchars; /* Internal API, so should not fail */ if (!ossl_assert(pkt->subs != NULL)) return 0; if ((sub = OPENSSL_zalloc(sizeof(*sub))) == NULL) { SSLerr(SSL_F_WPACKET_START_SUB_PACKET_LEN__, ERR_R_MALLOC_FAILURE); return 0; } sub->parent = pkt->subs; pkt->subs = sub; sub->pwritten = pkt->written + lenbytes; sub->lenbytes = lenbytes; if (lenbytes == 0) { sub->packet_len = 0; return 1; } if (!WPACKET_allocate_bytes(pkt, lenbytes, &lenchars)) return 0; /* Convert to an offset in case the underlying BUF_MEM gets realloc'd */ sub->packet_len = lenchars - GETBUF(pkt); return 1; } int WPACKET_start_sub_packet(WPACKET *pkt) { return WPACKET_start_sub_packet_len__(pkt, 0); } int WPACKET_put_bytes__(WPACKET *pkt, unsigned int val, size_t size) { unsigned char *data; /* Internal API, so should not fail */ if (!ossl_assert(size <= sizeof(unsigned int)) || !WPACKET_allocate_bytes(pkt, size, &data) || !put_value(data, val, size)) return 0; return 1; } int WPACKET_set_max_size(WPACKET *pkt, size_t maxsize) { WPACKET_SUB *sub; size_t lenbytes; /* Internal API, so should not fail */ if (!ossl_assert(pkt->subs != NULL)) return 0; /* Find the WPACKET_SUB for the top level */ for (sub = pkt->subs; sub->parent != NULL; sub = sub->parent) continue; lenbytes = sub->lenbytes; if (lenbytes == 0) lenbytes = sizeof(pkt->maxsize); if (maxmaxsize(lenbytes) < maxsize || maxsize < pkt->written) return 0; pkt->maxsize = maxsize; return 1; } int WPACKET_memset(WPACKET *pkt, int ch, size_t len) { unsigned char *dest; if (len == 0) return 1; if (!WPACKET_allocate_bytes(pkt, len, &dest)) return 0; memset(dest, ch, len); return 1; } int WPACKET_memcpy(WPACKET *pkt, const void *src, size_t len) { unsigned char *dest; if (len == 0) return 1; if (!WPACKET_allocate_bytes(pkt, len, &dest)) return 0; memcpy(dest, src, len); return 1; } int WPACKET_sub_memcpy__(WPACKET *pkt, const void *src, size_t len, size_t lenbytes) { if (!WPACKET_start_sub_packet_len__(pkt, lenbytes) || !WPACKET_memcpy(pkt, src, len) || !WPACKET_close(pkt)) return 0; return 1; } int WPACKET_get_total_written(WPACKET *pkt, size_t *written) { /* Internal API, so should not fail */ if (!ossl_assert(written != NULL)) return 0; *written = pkt->written; return 1; } int WPACKET_get_length(WPACKET *pkt, size_t *len) { /* Internal API, so should not fail */ if (!ossl_assert(pkt->subs != NULL && len != NULL)) return 0; *len = pkt->written - pkt->subs->pwritten; return 1; } unsigned char *WPACKET_get_curr(WPACKET *pkt) { return GETBUF(pkt) + pkt->curr; } void WPACKET_cleanup(WPACKET *pkt) { WPACKET_SUB *sub, *parent; for (sub = pkt->subs; sub != NULL; sub = parent) { parent = sub->parent; OPENSSL_free(sub); } pkt->subs = NULL; }