X-Git-Url: http://git.sameswireless.fr/l2tpns.git/blobdiff_plain/6dfe2883c9980a10796200e5c45499ac0b7e69b1..442b04cea2db5efc9636bb6a7d5b7166dee8fb3c:/ppp.c diff --git a/ppp.c b/ppp.c index 4d01e90..9661d5c 100644 --- a/ppp.c +++ b/ppp.c @@ -1809,130 +1809,299 @@ void processipin(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l) // process Multilink PPP packet received void processmpin(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l) { - bundleidt b = session[s].bundle; + bundleidt b = session[s].bundle; bundlet * this_bundle = &bundle[b]; - uint32_t frag_offset, M_offset; - uint16_t frag_index, M_index; + uint32_t maskSeq, max_seq; + int frag_offset; + uint16_t frag_index, frag_index_next, frag_index_prev; fragmentationt *this_fragmentation = &frag[b]; uint8_t begin_frame = (*p & MP_BEGIN); - uint8_t end_frame = (*p & MP_END); - uint32_t seq_num; + uint8_t end_frame = (*p & MP_END); + uint32_t seq_num, seq_num_next, seq_num_prev; + uint32_t i; uint8_t flags = *p; - uint16_t begin_index, end_index; + uint16_t begin_index, end_index, start_index; // Perform length checking - if(l > MAXFRAGLEN) - { - LOG(2, s, t, "MPPP: discarding fragment larger than MAXFRAGLEN\n"); - return; - } + if(l > MAXFRAGLEN) + { + LOG(2, s, t, "MPPP: discarding fragment larger than MAXFRAGLEN\n"); + return; + } - if(!b) - { - LOG(2, s, t, "MPPP: Invalid bundle id: 0\n"); - return; - } + if(!b) + { + LOG(2, s, t, "MPPP: Invalid bundle id: 0\n"); + return; + } // FIXME !! session[s].mssf means that the receiver wants to receive frames in mssf not means the receiver will send frames in mssf - /* if(session[s].mssf) - { - // Get 12 bit for seq number - seq_num = ntohs((*(uint16_t *) p) & 0xFF0F); - p += 2; - l -= 2; - // After this point the pointer should be advanced 2 bytes - LOG(3, s, t, "MPPP: 12 bits, sequence number: %d\n",seq_num); - } - else */ - { - // Get 24 bit for seq number - seq_num = ntohl((*(uint32_t *) p) & 0xFFFFFF00); - p += 4; - l -= 4; - // After this point the pointer should be advanced 4 bytes - LOG(4, s, t, "MPPP: 24 bits sequence number:%d\n",seq_num); - } + /* if(session[s].mssf) + { + // Get 12 bit for seq number + seq_num = ntohs((*(uint16_t *) p) & 0xFF0F); + p += 2; + l -= 2; + // After this point the pointer should be advanced 2 bytes + LOG(3, s, t, "MPPP: 12 bits, sequence number: %d\n",seq_num); + } + else */ + { + // Get 24 bit for seq number + seq_num = ntohl((*(uint32_t *) p) & 0xFFFFFF00); + p += 4; + l -= 4; + // After this point the pointer should be advanced 4 bytes + LOG(4, s, t, "MPPP: 24 bits sequence number:%d\n",seq_num); + } - // calculate this fragment's offset from the begin seq in the bundle - frag_offset = (seq_num + this_bundle->max_seq - this_fragmentation->start_seq) & (this_bundle->max_seq-1); + max_seq = this_bundle->max_seq; + maskSeq = max_seq - 1; - // discard this fragment if frag_offset is bigger that the fragmentation buffer size - if (frag_offset >= MAXFRAGNUM) - { - LOG(3, s, t, "MPPP: Index out of range, received more than MAXFRAGNUM fragment (lost frag) seq:%d, begin_seq:%d, bundle:%d, max:%d\n",seq_num, this_fragmentation->start_seq, b, this_bundle->max_seq); - return; - } + /* + * Expand sequence number to 32 bits, making it as close + * as possible to this_fragmentation->M. + */ + seq_num |= this_fragmentation->M & ~maskSeq; + if ((int)(this_fragmentation->M - seq_num) > (int)(maskSeq >> 1)) + { + seq_num += maskSeq + 1; + } + else if ((int)(seq_num - this_fragmentation->M) > (int)(maskSeq >> 1)) + { + seq_num -= maskSeq + 1; /* should never happen */ + } + + // calculate this fragment's offset from the begin seq in the bundle + frag_offset = (int) (seq_num - this_fragmentation->start_seq); + start_index = this_fragmentation->start_index; - // update M sess_local[s].last_seq = seq_num; + + uint32_t min; + if (seq_num < this_fragmentation->M) + { + min = seq_num; this_fragmentation->M = seq_num; + } else { - uint32_t i, min = sess_local[(this_bundle->members[0])].last_seq;; + min = sess_local[(this_bundle->members[0])].last_seq; for (i = 1; i < this_bundle->num_of_links; i++) { - uint32_t s_seq = sess_local[(this_bundle->members[i])].last_seq; + uint32_t s_seq = sess_local[(this_bundle->members[i])].last_seq; if (s_seq < min) min = s_seq; } this_fragmentation->M = min; } - LOG(4, s, t, "MPPP: Setting M to %d\n", this_fragmentation->M); - //calculate M's offset from the begin seq in the bundle - M_offset = (this_fragmentation->M + this_bundle->max_seq - this_fragmentation->start_seq) & (this_bundle->max_seq-1); + if (min >= (this_fragmentation->start_seq + this_bundle->num_of_links)) + { + // Find the new start sequence, the previous frag are lost + // calculate M offset of the M seq in the bundle + int M_offset = (int) (min - this_fragmentation->start_seq); + begin_index = (M_offset + this_fragmentation->start_index) & MAXFRAGNUM_MASK; + + if (M_offset >= MAXFRAGNUM) + { + // There have a long break of the link !!!!!!!! + // M_offset is bigger that the fragmentation buffer size + LOG(3, s, t, "MPPP: M_offset out of range, min:%d, begin_seq:%d, size frag:%d\n", min, this_fragmentation->start_seq, l); + + // Set new Start sequence + this_fragmentation->start_index = begin_index; + this_fragmentation->start_seq = min; + M_offset = 0; + // recalculate the fragment offset from the new begin seq in the bundle + frag_offset = (int) (seq_num - min); + } + else if (M_offset > 0) + { + uint32_t b_seq = min; + if (min == seq_num) + { + if (begin_frame) + { + // Set new Start sequence + this_fragmentation->start_index = begin_index; + this_fragmentation->start_seq = min; + frag_offset = 0; + } + } + else + { + // Find the Begin sequence + while (this_fragmentation->fragment[begin_index].length) + { + if (b_seq == this_fragmentation->fragment[begin_index].seq) + { + if (this_fragmentation->fragment[begin_index].flags & MP_BEGIN) + break; + } + else + { + // This fragment is lost, it was never completed the packet. + LOG(3, this_fragmentation->fragment[begin_index].sid, this_fragmentation->fragment[begin_index].tid, + "MPPP: (FIND) seq_num:%d frag_index:%d flags:%d is LOST\n", + this_fragmentation->fragment[begin_index].seq, begin_index, this_fragmentation->fragment[begin_index].flags); + // this frag is lost + this_fragmentation->fragment[begin_index].length = 0; + this_fragmentation->fragment[begin_index].flags = 0; + break; + } + begin_index = (begin_index ? (begin_index -1) : (MAXFRAGNUM -1)); + b_seq--; + } + + // begin sequence found ? + if (this_fragmentation->fragment[begin_index].length) + { + // Set new Start sequence + this_fragmentation->start_index = begin_index; + this_fragmentation->start_seq = b_seq; + // recalculate the fragment offset from the new begin seq in the bundle + frag_offset = (int) (seq_num - b_seq); + } + } + } + } + else if ((this_fragmentation->fragment[start_index].length) && + (!(this_fragmentation->fragment[start_index].flags & MP_BEGIN))) + { + uint32_t f_seq = this_fragmentation->start_seq; + end_index = start_index; + // Find the Begin sequence + while (this_fragmentation->fragment[end_index].length) + { + if (f_seq == this_fragmentation->fragment[end_index].seq) + { + if (this_fragmentation->fragment[end_index].flags & MP_BEGIN) + break; + } + else + { + // This fragment is lost, it was never completed the packet. + LOG(3, this_fragmentation->fragment[end_index].sid, this_fragmentation->fragment[end_index].tid, + "MPPP: (FIND2) seq_num:%d frag_index:%d flags:%d is LOST\n", + this_fragmentation->fragment[end_index].seq, end_index, this_fragmentation->fragment[end_index].flags); + // this frag is lost + this_fragmentation->fragment[end_index].length = 0; + this_fragmentation->fragment[end_index].flags = 0; + break; + } + end_index = (end_index +1) & MAXFRAGNUM_MASK; + f_seq++; + } + + // Set new Start sequence + this_fragmentation->start_index = end_index; + this_fragmentation->start_seq = f_seq; + // recalculate the fragment offset from the new begin seq in the bundle + frag_offset = (int) (seq_num - f_seq); + } - //caculate M's index in the fragment array - M_index = (M_offset + this_fragmentation->start_index) & MAXFRAGNUM_MASK; + // discard this fragment if the packet comes before the start sequence + if (frag_offset < 0) + { + // this packet comes before the next + LOG(3, s, t, "MPPP: packet comes before the next, seq:%d, begin_seq:%d, size frag:%d\n", seq_num, this_fragmentation->start_seq, l); + return; + } + // discard if frag_offset is bigger that the fragmentation buffer size + if (frag_offset >= MAXFRAGNUM) + { + // frag_offset is bigger that the fragmentation buffer size + LOG(3, s, t, "MPPP: Index out of range, seq:%d, begin_seq:%d, size frag:%d\n", seq_num, this_fragmentation->start_seq, l); + return; + } + //caculate received fragment's index in the fragment array frag_index = (frag_offset + this_fragmentation->start_index) & MAXFRAGNUM_MASK; - //frame with a single fragment - if (begin_frame && end_frame) - { - // process and reset fragmentation - LOG(4, s, t, "MPPP: Both bits are set (Begin and End).\n"); - this_fragmentation->fragment[frag_index].length = l; - this_fragmentation->fragment[frag_index].sid = s; - this_fragmentation->fragment[frag_index].flags = flags; - this_fragmentation->fragment[frag_index].seq = seq_num; - this_fragmentation->re_frame_begin_index = frag_index; - this_fragmentation->re_frame_end_index = frag_index; - processmpframe(s, t, p, l, 0); - this_fragmentation->fragment[frag_index].length = 0; - this_fragmentation->fragment[frag_index].flags = 0; - end_index = frag_index; - } - else { // insert the frame in it's place fragmentt *this_frag = &this_fragmentation->fragment[frag_index]; + + if (this_frag->length > 0) + // This fragment is lost, It was around the buffer and it was never completed the packet. + LOG(3, this_frag->sid, this_frag->tid, "MPPP: (INSERT) seq_num:%d frag_index:%d flags:%d is LOST\n", + this_frag->seq, frag_index, this_frag->flags); + this_frag->length = l; this_frag->sid = s; this_frag->flags = flags; this_frag->seq = seq_num; - memcpy(this_frag->data, p, l); + memcpy(this_frag->data, p, l); + + LOG(4, s, t, "MPPP: seq_num:%d frag_index:%d INSERTED flags: %02X\n", seq_num, frag_index, flags); + + //next frag index + frag_index_next = (frag_index + 1) & MAXFRAGNUM_MASK; + //previous frag index + frag_index_prev = (frag_index - 1) & MAXFRAGNUM_MASK; + // next seq + seq_num_next = seq_num + 1; + // previous seq + seq_num_prev = seq_num - 1; + + if ((frag_index_next != this_fragmentation->start_index) && this_fragmentation->fragment[frag_index_next].length) + { + // check if the next frag is a lost fragment + if (this_fragmentation->fragment[frag_index_next].seq != seq_num_next) + { + // This fragment is lost, It was around the buffer and it was never completed the packet. + LOG(3, this_fragmentation->fragment[frag_index_next].sid, this_fragmentation->fragment[frag_index_next].tid, + "MPPP: (NEXT) seq_num:%d frag_index:%d flags:%d is LOST\n", + this_fragmentation->fragment[frag_index_next].seq, frag_index_next, this_fragmentation->fragment[frag_index_next].flags); + // this frag is lost + this_fragmentation->fragment[frag_index_next].length = 0; + this_fragmentation->fragment[frag_index_next].flags = 0; + + if (begin_frame && (!end_frame)) return; // assembling frame failed + } + } + + if ((frag_index != this_fragmentation->start_index) && this_fragmentation->fragment[frag_index_prev].length) + { + // check if the next frag is a lost fragment + if (this_fragmentation->fragment[frag_index_prev].seq != seq_num_prev) + { + // This fragment is lost, It was around the buffer and it was never completed the packet. + LOG(3, this_fragmentation->fragment[frag_index_prev].sid, this_fragmentation->fragment[frag_index_prev].tid, + "MPPP: (PREV) seq_num:%d frag_index:%d flags:%d is LOST\n", + this_fragmentation->fragment[frag_index_prev].seq, frag_index_prev, this_fragmentation->fragment[frag_index_prev].flags); + this_fragmentation->fragment[frag_index_prev].length = 0; + this_fragmentation->fragment[frag_index_prev].flags = 0; + + if (end_frame && (!begin_frame)) return; // assembling frame failed + } + } + +assembling_frame: // try to assemble the frame that has the received fragment as a member // get the beginning of this frame - begin_index = end_index = frag_index; - while (this_fragmentation->fragment[begin_index].length) + begin_index = end_index = this_fragmentation->start_index; + if (this_fragmentation->fragment[begin_index].length) { - if (this_fragmentation->fragment[begin_index].flags & MP_BEGIN) - break; - begin_index = (begin_index ? (begin_index -1) : (MAXFRAGNUM -1)); + if (!(this_fragmentation->fragment[begin_index].flags & MP_BEGIN)) + return; // assembling frame failed } - - // return if a lost fragment is found - if (!(this_fragmentation->fragment[begin_index].length)) + else return; // assembling frame failed + // get the end of his frame while (this_fragmentation->fragment[end_index].length) { if (this_fragmentation->fragment[end_index].flags & MP_END) break; - end_index = (end_index +1) & MAXFRAGNUM_MASK; + + end_index = (end_index +1) & MAXFRAGNUM_MASK; + + if (end_index == this_fragmentation->start_index) + return; // assembling frame failed } // return if a lost fragment is found @@ -1942,35 +2111,37 @@ void processmpin(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l) // assemble the packet //assemble frame, process it, reset fragmentation uint16_t cur_len = 4; // This is set to 4 to leave 4 bytes for function processipin - uint32_t i; - LOG(4, s, t, "MPPP: processing fragments from %d to %d\n", begin_index, end_index); - // Push to the receive buffer - + LOG(4, s, t, "MPPP: processing fragments from %d to %d\n", begin_index, end_index); + // Push to the receive buffer + for (i = begin_index;; i = (i + 1) & MAXFRAGNUM_MASK) - { + { this_frag = &this_fragmentation->fragment[i]; - if(cur_len + this_frag->length > MAXETHER) - { - LOG(2, s, t, "MPPP: discarding reassembled frames larger than MAXETHER\n"); - break; - } - memcpy(this_fragmentation->reassembled_frame+cur_len, this_frag->data, this_frag->length); + if(cur_len + this_frag->length > MAXETHER) + { + LOG(2, s, t, "MPPP: discarding reassembled frames larger than MAXETHER\n"); + break; + } + + memcpy(this_fragmentation->reassembled_frame+cur_len, this_frag->data, this_frag->length); LOG(5, s, t, "MPPP: processing frame at %d, with len %d\n", i, this_frag->length); - cur_len += this_frag->length; + + cur_len += this_frag->length; if (i == end_index) { this_fragmentation->re_frame_len = cur_len; this_fragmentation->re_frame_begin_index = begin_index; - this_fragmentation->re_frame_end_index = end_index; - // Process the resassembled frame - LOG(5, s, t, "MPPP: Process the reassembled frame, len=%d\n",cur_len); - processmpframe(s, t, this_fragmentation->reassembled_frame, this_fragmentation->re_frame_len, 1); + this_fragmentation->re_frame_end_index = end_index; + // Process the resassembled frame + LOG(5, s, t, "MPPP: Process the reassembled frame, len=%d\n",cur_len); + processmpframe(s, t, this_fragmentation->reassembled_frame, this_fragmentation->re_frame_len, 1); break; } - } - // Set reassembled frame length to zero after processing it - this_fragmentation->re_frame_len = 0; + } + + // Set reassembled frame length to zero after processing it + this_fragmentation->re_frame_len = 0; for (i = begin_index;; i = (i + 1) & MAXFRAGNUM_MASK) { this_fragmentation->fragment[i].length = 0; // Indicates that this fragment has been consumed @@ -1978,20 +2149,32 @@ void processmpin(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l) if (i == end_index) break; } + + // Set the new start_index and start_seq + this_fragmentation->start_index = (end_index + 1) & MAXFRAGNUM_MASK; + this_fragmentation->start_seq = this_fragmentation->fragment[end_index].seq + 1; + + LOG(4, s, t, "MPPP after assembling: start index is = %d, start seq=%d\n", this_fragmentation->start_index, this_fragmentation->start_seq); + + begin_index = this_fragmentation->start_index; + if (this_fragmentation->fragment[begin_index].length) + { + if (this_fragmentation->fragment[begin_index].seq == this_fragmentation->start_seq) + { + if (this_fragmentation->fragment[begin_index].flags & MP_BEGIN) + goto assembling_frame; + } + else + { + LOG(3, this_fragmentation->fragment[begin_index].sid, this_fragmentation->fragment[begin_index].tid, + "MPPP: START seq_num:%d frag_index:%d flags:%d is LOST\n", + this_fragmentation->fragment[begin_index].seq, begin_index, this_fragmentation->fragment[begin_index].flags); + this_fragmentation->fragment[begin_index].length = 0; + this_fragmentation->fragment[begin_index].flags = 0; + } + } } - //discard fragments received before the recently assembled frame - begin_index = this_fragmentation->start_index; - this_fragmentation->start_index = (end_index + 1) & MAXFRAGNUM_MASK; - this_fragmentation->start_seq = (this_fragmentation->fragment[end_index].seq + 1) & (this_bundle->max_seq-1); - //clear length and flags of the discarded fragments - while (begin_index != this_fragmentation->start_index) - { - this_fragmentation->fragment[begin_index].flags = 0; - this_fragmentation->fragment[begin_index].length = 0; - begin_index = (begin_index + 1) & MAXFRAGNUM_MASK; - } - LOG(4, s, t, "MPPP after assembling: M index is =%d, start index is = %d, start seq=%d\n",M_index, this_fragmentation->start_index, this_fragmentation->start_seq); return; } @@ -2373,7 +2556,7 @@ uint8_t *makeppp(uint8_t *b, int size, uint8_t *p, int l, sessionidt s, tunnelid if ((b - start) + l > size) { - LOG(2, s, t, "makeppp would overflow buffer (size=%d, header+payload=%ld)\n", size, (b - start) + l); + LOG(2, s, t, "makeppp would overflow buffer (size=%d, header+payload=%td)\n", size, (b - start) + l); return NULL; }