1 /* 2 * Copyright 2018 Google Inc. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include "cable.hpp" 18 19 #include "errors.hpp" 20 #include "handler.hpp" 21 #include "ipmi.hpp" 22 23 #include <cstdint> 24 #include <cstring> 25 #include <string> 26 27 namespace google 28 { 29 namespace ipmi 30 { 31 32 struct CableRequest 33 { 34 uint8_t subcommand; 35 uint8_t ifNameLength; 36 uint8_t ifName[0]; 37 } __attribute__((packed)); 38 39 ipmi_ret_t cableCheck(const uint8_t* reqBuf, uint8_t* replyBuf, size_t* dataLen, 40 const HandlerInterface* handler) 41 { 42 // There is an IPMI LAN channel statistics command which could be used for 43 // this type of check, however, we're not able to wait for the OpenBMC 44 // implementation to stabilize related to the network management. 45 // 46 // There is a link status file, but it is "unknown" to start with... 47 // The path we're checking: /sys/class/net/eth1/statistics/rx_packets 48 49 // This command is expecting: [0x00][len][ifName] 50 if ((*dataLen) < sizeof(struct CableRequest) + sizeof(uint8_t)) 51 { 52 std::fprintf(stderr, "Invalid command length: %u\n", 53 static_cast<uint32_t>(*dataLen)); 54 return IPMI_CC_REQ_DATA_LEN_INVALID; 55 } 56 57 const auto request = 58 reinterpret_cast<const struct CableRequest*>(&reqBuf[0]); 59 60 // Sanity check the object contents. 61 if (request->ifNameLength == 0) 62 { 63 std::fprintf(stderr, "Invalid string length: %d\n", 64 request->ifNameLength); 65 return IPMI_CC_REQ_DATA_LEN_INVALID; 66 } 67 68 // Verify the request buffer contains the object and the string. 69 if ((*dataLen) < (sizeof(struct CableRequest) + request->ifNameLength)) 70 { 71 std::fprintf(stderr, "*dataLen too small: %u\n", 72 static_cast<uint32_t>(*dataLen)); 73 return IPMI_CC_REQ_DATA_LEN_INVALID; 74 } 75 76 // Maximum length one can specify, plus null terminator. 77 char nameBuf[256] = {}; 78 // Copy the string out of the request buffer. 79 std::memcpy(&nameBuf[0], request->ifName, request->ifNameLength); 80 std::string name = nameBuf; 81 int64_t count; 82 83 try 84 { 85 count = handler->getRxPackets(name); 86 } 87 catch (const IpmiException& e) 88 { 89 return e.getIpmiError(); 90 } 91 92 struct CableReply reply; 93 reply.subcommand = SysCableCheck; 94 95 // If we have received packets then there is a cable present. 96 reply.value = (count > 0) ? 1 : 0; 97 98 // Return the subcommand and the result. 99 std::memcpy(&replyBuf[0], &reply, sizeof(struct CableReply)); 100 (*dataLen) = sizeof(struct CableReply); 101 102 return IPMI_CC_OK; 103 } 104 105 } // namespace ipmi 106 } // namespace google 107