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Diffstat (limited to 'modules/es_unix/unix_cmd.cpp')
| -rw-r--r-- | modules/es_unix/unix_cmd.cpp | 241 |
1 files changed, 241 insertions, 0 deletions
diff --git a/modules/es_unix/unix_cmd.cpp b/modules/es_unix/unix_cmd.cpp new file mode 100644 index 000000000..db79478df --- /dev/null +++ b/modules/es_unix/unix_cmd.cpp @@ -0,0 +1,241 @@ +/************************************************* +* Unix Command Execution Source File * +* (C) 1999-2006 The Botan Project * +*************************************************/ + +#ifndef _XOPEN_SOURCE + #define _XOPEN_SOURCE 500 +#endif + +#ifndef _XOPEN_SOURCE_EXTENDED + #define _XOPEN_SOURCE_EXTENDED 1 +#endif + +#include <botan/unix_cmd.h> +#include <botan/parsing.h> +#include <sys/time.h> +#include <sys/types.h> +#include <sys/wait.h> +#include <unistd.h> +#include <signal.h> + +namespace Botan { + +namespace { + +/************************************************* +* Attempt to execute the command * +************************************************/ +void do_exec(const std::vector<std::string>& arg_list, + const std::vector<std::string>& paths) + { + const u32bit args = arg_list.size() - 1; + + const char* arg1 = (args >= 1) ? arg_list[1].c_str() : 0; + const char* arg2 = (args >= 2) ? arg_list[2].c_str() : 0; + const char* arg3 = (args >= 3) ? arg_list[3].c_str() : 0; + const char* arg4 = (args >= 4) ? arg_list[4].c_str() : 0; + + for(u32bit j = 0; j != paths.size(); j++) + { + const std::string full_path = paths[j] + "/" + arg_list[0]; + const char* fsname = full_path.c_str(); + execl(fsname, fsname, arg1, arg2, arg3, arg4, 0); + } + } + +} + +/************************************************* +* Local information about the pipe * +*************************************************/ +struct pipe_wrapper + { + int fd; + pid_t pid; + pipe_wrapper() { fd = -1; pid = 0; } + }; + +/************************************************* +* Read from the pipe * +*************************************************/ +u32bit DataSource_Command::read(byte buf[], u32bit length) + { + if(end_of_data()) + return 0; + + fd_set set; + FD_ZERO(&set); + FD_SET(pipe->fd, &set); + + struct timeval tv; + tv.tv_sec = 0; + tv.tv_usec = MAX_BLOCK_USECS; + + ssize_t got = 0; + if(select(pipe->fd + 1, &set, 0, 0, &tv) == 1) + { + if(FD_ISSET(pipe->fd, &set)) + got = ::read(pipe->fd, buf, length); + } + + if(got <= 0) + { + shutdown_pipe(); + return 0; + } + + return (u32bit)got; + } + +/************************************************* +* Peek at the pipe contents * +*************************************************/ +u32bit DataSource_Command::peek(byte[], u32bit, u32bit) const + { + if(end_of_data()) + throw Invalid_State("DataSource_Command: Cannot peek when out of data"); + throw Stream_IO_Error("Cannot peek/seek on a command pipe"); + } + +/************************************************* +* Check if we reached EOF * +*************************************************/ +bool DataSource_Command::end_of_data() const + { + return (pipe) ? false : true; + } + +/************************************************* +* Return the Unix file descriptor of the pipe * +*************************************************/ +int DataSource_Command::fd() const + { + if(!pipe) + return -1; + return pipe->fd; + } + +/************************************************* +* Return a human-readable ID for this stream * +*************************************************/ +std::string DataSource_Command::id() const + { + return "Unix command: " + arg_list[0]; + } + +/************************************************* +* Create the pipe * +*************************************************/ +void DataSource_Command::create_pipe(const std::string& path) + { + const std::vector<std::string> paths = split_on(path, ':'); + + bool found_something = false; + for(u32bit j = 0; j != paths.size(); j++) + { + const std::string full_path = paths[j] + "/" + arg_list[0]; + if(access(full_path.c_str(), X_OK) == 0) + { + found_something = true; + break; + } + } + if(!found_something) + return; + + int pipe_fd[2]; + if(::pipe(pipe_fd) != 0) + return; + + pid_t pid = fork(); + + if(pid == -1) + { + close(pipe_fd[0]); + close(pipe_fd[1]); + } + else if(pid > 0) + { + pipe = new pipe_wrapper; + pipe->fd = pipe_fd[0]; + pipe->pid = pid; + close(pipe_fd[1]); + } + else + { + if(dup2(pipe_fd[1], STDOUT_FILENO) == -1) + exit(127); + if(close(pipe_fd[0]) != 0 || close(pipe_fd[1]) != 0) + exit(127); + if(close(STDERR_FILENO) != 0) + exit(127); + + do_exec(arg_list, paths); + exit(127); + } + } + +/************************************************* +* Shutdown the pipe * +*************************************************/ +void DataSource_Command::shutdown_pipe() + { + if(pipe) + { + pid_t reaped = waitpid(pipe->pid, 0, WNOHANG); + + if(reaped == 0) + { + kill(pipe->pid, SIGTERM); + + struct timeval tv; + tv.tv_sec = 0; + tv.tv_usec = KILL_WAIT; + select(0, 0, 0, 0, &tv); + + reaped = waitpid(pipe->pid, 0, WNOHANG); + + if(reaped == 0) + { + kill(pipe->pid, SIGKILL); + do + reaped = waitpid(pipe->pid, 0, 0); + while(reaped == -1); + } + } + + close(pipe->fd); + delete pipe; + pipe = 0; + } + } + +/************************************************* +* DataSource_Command Constructor * +*************************************************/ +DataSource_Command::DataSource_Command(const std::string& prog_and_args, + const std::string& path) : + MAX_BLOCK_USECS(100000), KILL_WAIT(10000) + { + arg_list = split_on(prog_and_args, ' '); + + if(arg_list.size() == 0) + throw Invalid_Argument("DataSource_Command: No command given"); + if(arg_list.size() > 5) + throw Invalid_Argument("DataSource_Command: Too many args"); + + pipe = 0; + create_pipe(path); + } + +/************************************************* +* DataSource_Command Destructor * +*************************************************/ +DataSource_Command::~DataSource_Command() + { + if(!end_of_data()) + shutdown_pipe(); + } + +} |