diff options
| -rw-r--r-- | dummyshell.c | 72 |
1 files changed, 59 insertions, 13 deletions
diff --git a/dummyshell.c b/dummyshell.c index 9dab72e..aa0d307 100644 --- a/dummyshell.c +++ b/dummyshell.c @@ -27,6 +27,7 @@ #ifdef _HAS_MSG #include <errno.h> #include <string.h> +#include <sys/stat.h> #else #warning "MESSAGE(_HAS_MSG) disabled!" #endif @@ -105,16 +106,21 @@ static char readInput(char* buf, size_t* siz, size_t szMax, char key, int flags) } #ifdef _HAS_CMD +#define NO_ARGS 0b00000001 +#define NEED_ARGS 0b00000010 struct __attribute__((__packed__)) cmd { char* name; char* path; char* defargs; + unsigned char flags; }; static struct cmd cmds[] = { - { "ether-wake", "/var/media/ftp/bin/suid-ether-wake", "-b -i lan" }, - { "echo", "/bin/echo", NULL }, - { NULL, NULL, NULL } + { "ether-wake", "/var/media/ftp/bin/suid-ether-wake", "-b -i lan", NEED_ARGS }, + { "netstat-client", "/bin/netstat", "-pntu", NO_ARGS }, + { "netstat-server", "/bin/netstat", "-lpn", NO_ARGS }, + { "echo", "/bin/echo", NULL, NEED_ARGS }, + { NULL, NULL, NULL, 0 } }; static void print_cmds(void) @@ -122,11 +128,13 @@ static void print_cmds(void) size_t idx = 0; printf("\33[2K\r[COMMANDS]\n"); while ( cmds[idx++].path != NULL ) { - printf(" [%lu] %s\n", (unsigned long int)idx-1, ( cmds[idx-1].name != NULL ? cmds[idx-1].name : "unknown" )); + printf(" [%lu] %s [%s]\n", (unsigned long int)idx-1, + ( cmds[idx-1].name != NULL ? cmds[idx-1].name : "unknown" ), + ( cmds[idx-1].defargs != NULL ? cmds[idx-1].defargs : "" )); } } -int safe_exec(const char* cmdWithArgs) +static int safe_exec(const char* cmdWithArgs) { pid_t child; if ( (child = fork()) == 0 ) { @@ -170,10 +178,25 @@ static int exec_cmd(size_t i, char* args, size_t szArgs) size_t idx = (size_t)-1; while ( cmds[++idx].path != NULL ) { if (idx == i) { + if (cmds[idx].flags & NEED_ARGS) { + if (!args) + return -9; + if (strnlen(args, szArgs) < 1) + return -9; + } else if (cmds[idx].flags & NO_ARGS) { + if (args) + return -8; + } size_t siz = strlen(cmds[idx].path)+szArgs+1; + if (cmds[idx].defargs) + siz += strlen(cmds[idx].defargs)+2; char execbuf[siz+1]; memset(&execbuf[0], '\0', siz+1); - snprintf(&execbuf[0], siz+1, "%s %s", cmds[idx].path, args); + if (cmds[idx].defargs) { + snprintf(&execbuf[0], siz+1, "%s %s %s", cmds[idx].path, cmds[idx].defargs, args); + } else { + snprintf(&execbuf[0], siz+1, "%s %s", cmds[idx].path, args); + } return safe_exec(&execbuf[0]); } } @@ -187,13 +210,23 @@ static int exec_cmd(size_t i, char* args, size_t szArgs) static int msgfd = -1; static int init_msg(void) { + umask(664); + struct stat buf; + memset(&buf, '\0', sizeof(buf)); + if (stat(MSGFILE, &buf) == 0) { + if (!S_ISREG(buf.st_mode) || !(buf.st_mode & S_IRUSR) || !(buf.st_mode & S_IWUSR) || + !(buf.st_mode & S_IRGRP) || !(buf.st_mode & S_IWGRP) || !(buf.st_mode & S_IROTH)) { + fprintf(stderr, "file (`%s`) mode should be 0664\n", MSGFILE); + return -1; + } + } else return -1; msgfd = open(MSGFILE, O_RDWR | O_CREAT | O_APPEND | O_DSYNC | O_RSYNC, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH); if (msgfd < 0) { fprintf(stderr, "fopen(\"%s\") with write access: %s\n", MSGFILE, strerror(errno)); msgfd = open(MSGFILE, O_RDONLY | O_CREAT | O_APPEND | O_DSYNC | O_RSYNC); if (msgfd < 0) { fprintf(stderr, "fopen(\"%s\") readonly: %s\n", MSGFILE, strerror(errno)); - return -1; + return -2; } } return 0; @@ -445,8 +478,10 @@ int main(int argc, char** argv) char inputbuf[absiz+1]; memset(&inputbuf[0], '\0', absiz+1); #ifdef _HAS_MSG - if (init_msg() != 0) + if (init_msg() != 0) { + fprintf(stderr, "init msg failed\n"); return 1; + } if (argc > 1) { const char optRmsg[] = "readmsg"; const char optWmsg[] = "writemsg"; @@ -588,16 +623,27 @@ int main(int argc, char** argv) } else if (state == MS_COMMAND) { #ifdef _HAS_CMD int inputFail = 0; - if (inputsiz < 3) { + if (inputsiz < 1) { inputFail++; } else { char* endptr = NULL; + size_t szEndptr = 0; unsigned long int tmpi = strtoul(inputbuf, &endptr, 10); + const char exec_str[] = "\33[2K\rExec CMD #"; if (*endptr == ' ') { endptr++; - printf("\33[2K\rExec CMD #%lu with args: %s\n", tmpi, endptr); + szEndptr = strnlen(endptr, inputsiz-1); + printf("%s%lu with args: %s\n", exec_str, tmpi, endptr); + } else if (*endptr == '\0') { + printf("%s%lu\n", exec_str, tmpi); + endptr = NULL; + } else inputFail++; + + if (inputFail == 0) { int retval; - switch ( (retval = exec_cmd(tmpi, endptr, strlen(endptr))) ) { + switch ( (retval = exec_cmd(tmpi, endptr, szEndptr)) ) { + case -9: printf("args required for cmd #%lu\n", tmpi); break; + case -8: printf("no args allowed for cmd #%lu\n", tmpi); break; case -7: printf("unknown cmd #%lu\n", tmpi); break; case -6: printf("fork error cmd #%lu\n", tmpi); break; case -5: printf("execute cmd #%lu\n", tmpi); break; @@ -605,10 +651,10 @@ int main(int argc, char** argv) case 0: break; default: printf("Something went wrong, child returned: %d\n", retval); break; } - } else inputFail++; + } } if (inputFail > 0) - printf("\33[2K\rFORMAT: [cmd#] [params]\n"); + printf("\33[2K\rFORMAT: [cmd# [params]]\n"); } #endif } |