C變量和內存問題

Question

我的代碼有問題，以某種方式，變量receiver_buffer從json_packet或函數external_auth_format_packet中的uu獲取了一些數據。

在這里您可以在日志中看到：

Sep 26 12:35:07 ubuntu sshd[58912]: userauth_external: DEBUG: socket_path: /tmp/auth.sock
Sep 26 12:35:07 ubuntu sshd[58912]: userauth_external: DEBUG: json_packet: {"user": "root", "key": "AAAAB3NzaC1yc2EAAAADAQABAAABAQDwHDG/TpoUDts9CFrUWh6eoOlPcQYTLIpkF1udDaRZMsdZSZyDsWO5otqrUiQuVLFBXKa4CMiYBJIll2Ye/ZMWjbWd6mkrhE/u4Ha+DS6wyoza3mgn4ekDYxHqzk6/9kVnNtdh+sw3h0OwhkJJG/fAGzGFZhaV5bRS8f9u6pxIKTdmUfozkfe/QhYlFS9gaFnlK2rn8efK1oeNL00YBEcFLVeFdFqU9xuTOrHIQuOHxEynF/zekJ69D1MDhLZDhzq7mfy00wOnS51Q0gxZUdBiFr0ahuD/WrxKgwYunAsp1hD22+WU89vmoPtonWE7a6hTeZtz6Mb0YPfmRwz+CaR1", "type": "ssh-rsa"}
Sep 26 12:35:07 ubuntu sshd[58912]: userauth_external: DEBUG: sent json_packet to server
Sep 26 12:35:07 ubuntu sshd[58912]: userauth_external: DEBUG: receiver_buffer memory allocation
Sep 26 12:35:07 ubuntu sshd[58912]: userauth_external: DEBUG: recv has received: {"status":1,"command":"command='./gitserve' "}
Sep 26 12:35:07 ubuntu sshd[58912]: userauth_external: DEBUG: copying from tmp_buffer to receiver_buffer
Sep 26 12:35:07 ubuntu sshd[58912]: userauth_external: DEBUG: finished receiving data from socket
Sep 26 12:35:07 ubuntu sshd[58912]: error: userauth_external: ERROR: Unable to load parmaters! error: on line 1: end of file expected near 'rUWh'\n
Sep 26 12:35:07 ubuntu sshd[58912]: error: userauth_external: ERROR: response {"status":1,"command":"command='./gitserve' "}rUWh6eoOlPcQYTLIpkF1udDaRZMsdZSZyDsWO5otqrUiQuVLFBXKa4CMiYBJIll2Ye/ZMWjbWd6mkrhE/u4Ha+DS6wyoza3mgn4ekDYxHqzk6/9kVnNtdh+sw3h0OwhkJJG/fAGzGFZhaV5bRS8f9u6pxIKTdmUfozkfe/QhYlFS9gaFnlK2rn8efK1oeNL00YBEcFLVeFdFqU9xuTOrHIQuOHxEynF/zekJ69D1MDhLZDhzq7mfy00wOnS51Q0gxZUdBiFr0ahuD/WrxKgwYunAsp1hD22+WU89vmoPtonWE7a6hTeZtz6Mb0YPfmRwz+CaR1

從套接字receive_buffer接收數據

{"status":1,"command":"command='./gitserve' "}

但是隨后詹森嘗試將其視為不屬於該變量的數據進行解析

{"status":1,"command":"command='./gitserve' "}rUWh6eoOlPcQYTLIpkF1udDaRZMsdZSZyDsWO5otqrUiQuVLFBXKa4CMiYBJIll2Ye/ZMWjbWd6mkrhE/u4Ha+DS6wyoza3mgn4ekDYxHqzk6/9kVnNtdh+sw3h0OwhkJJG/fAGzGFZhaV5bRS8f9u6pxIKTdmUfozkfe/QhYlFS9gaFnlK2rn8efK1oeNL00YBEcFLVeFdFqU9xuTOrHIQuOHxEynF/zekJ69D1MDhLZDhzq7mfy00wOnS51Q0gxZUdBiFr0ahuD/WrxKgwYunAsp1hD22+WU89vmoPtonWE7a6hTeZtz6Mb0YPfmRwz+CaR1`

函數的源代碼http://pastebin.com/P7WnhsqX

Answer 1

memcpy(receiver_buffer + total_received_chars, tmp_buffer, received_chars);

您正在復制接收的字符字節，它是字符串長度-不包括終止'\\ 0'字節。 稍后，當您嘗試使用它時-您將擁有字符串+緩沖區的其余部分，因為您不知道需要讀取多少內容。