Merge pull request #2177 from RincewindsHat/modern_output/check_by_sshHEADmastercoverity/master

Modern output/check by ssh

2 files changed, 300 insertions, 10 deletions

diff --git a/lib/utils_cmd.c b/lib/utils_cmd.c
index 35b83297..42c81793 100644
--- a/lib/utils_cmd.c
+++ b/lib/utils_cmd.c
@@ -56,6 +56,7 @@ static pid_t *_cmd_pids = NULL;
 #include "./maxfd.h"
 
 #include <fcntl.h>
+#include <stddef.h>
 
 #ifdef HAVE_SYS_WAIT_H
 #       include <sys/wait.h>
@@ -79,7 +80,8 @@ static pid_t *_cmd_pids = NULL;
 static int _cmd_open(char *const *argv, int *pfd, int *pfderr)
         __attribute__((__nonnull__(1, 2, 3)));
 
-static int _cmd_fetch_output(int fileDescriptor, output *cmd_output, int flags) __attribute__((__nonnull__(2)));
+static int _cmd_fetch_output(int fileDescriptor, output *cmd_output, int flags)
+        __attribute__((__nonnull__(2)));
 
 static int _cmd_close(int fileDescriptor);
 
@@ -102,14 +104,85 @@ void cmd_init(void) {
         }
 }
 
+typedef struct {
+        int stdout_pipe_fd[2];
+        int stderr_pipe_fd[2];
+        int file_descriptor;
+        int error_code;
+} int_cmd_open_result;
+static int_cmd_open_result _cmd_open2(char *const *argv) {
+#ifdef RLIMIT_CORE
+        struct rlimit limit;
+#endif
+
+        if (!_cmd_pids) {
+                CMD_INIT;
+        }
+
+        setenv("LC_ALL", "C", 1);
+
+        int_cmd_open_result result = {
+                .error_code = 0,
+                .stdout_pipe_fd = {0, 0},
+                .stderr_pipe_fd = {0, 0},
+        };
+        pid_t pid;
+        if (pipe(result.stdout_pipe_fd) < 0 || pipe(result.stderr_pipe_fd) < 0 || (pid = fork()) < 0) {
+                result.error_code = -1;
+                return result; /* errno set by the failing function */
+        }
+
+        /* child runs exceve() and _exit. */
+        if (pid == 0) {
+#ifdef RLIMIT_CORE
+                /* the program we execve shouldn't leave core files */
+                getrlimit(RLIMIT_CORE, &limit);
+                limit.rlim_cur = 0;
+                setrlimit(RLIMIT_CORE, &limit);
+#endif
+                close(result.stdout_pipe_fd[0]);
+                if (result.stdout_pipe_fd[1] != STDOUT_FILENO) {
+                        dup2(result.stdout_pipe_fd[1], STDOUT_FILENO);
+                        close(result.stdout_pipe_fd[1]);
+                }
+                close(result.stderr_pipe_fd[0]);
+                if (result.stderr_pipe_fd[1] != STDERR_FILENO) {
+                        dup2(result.stderr_pipe_fd[1], STDERR_FILENO);
+                        close(result.stderr_pipe_fd[1]);
+                }
+
+                /* close all descriptors in _cmd_pids[]
+                 * This is executed in a separate address space (pure child),
+                 * so we don't have to worry about async safety */
+                long maxfd = mp_open_max();
+                for (int i = 0; i < maxfd; i++) {
+                        if (_cmd_pids[i] > 0) {
+                                close(i);
+                        }
+                }
+
+                execve(argv[0], argv, environ);
+                _exit(STATE_UNKNOWN);
+        }
+
+        /* parent picks up execution here */
+        /* close children descriptors in our address space */
+        close(result.stdout_pipe_fd[1]);
+        close(result.stderr_pipe_fd[1]);
+
+        /* tag our file's entry in the pid-list and return it */
+        _cmd_pids[result.stdout_pipe_fd[0]] = pid;
+
+        result.file_descriptor = result.stdout_pipe_fd[0];
+        return result;
+}
+
 /* Start running a command, array style */
 static int _cmd_open(char *const *argv, int *pfd, int *pfderr) {
 #ifdef RLIMIT_CORE
         struct rlimit limit;
 #endif
 
-        int i = 0;
-
         if (!_cmd_pids) {
                 CMD_INIT;
         }
@@ -144,7 +217,7 @@ static int _cmd_open(char *const *argv, int *pfd, int *pfderr) {
                  * This is executed in a separate address space (pure child),
                  * so we don't have to worry about async safety */
                 long maxfd = mp_open_max();
-                for (i = 0; i < maxfd; i++) {
+                for (int i = 0; i < maxfd; i++) {
                         if (_cmd_pids[i] > 0) {
                                 close(i);
                         }
@@ -192,6 +265,87 @@ static int _cmd_close(int fileDescriptor) {
         return (WIFEXITED(status)) ? WEXITSTATUS(status) : -1;
 }
 
+typedef struct {
+        int error_code;
+        output output_container;
+} int_cmd_fetch_output2;
+static int_cmd_fetch_output2 _cmd_fetch_output2(int fileDescriptor, int flags) {
+        char tmpbuf[4096];
+
+        int_cmd_fetch_output2 result = {
+                .error_code = 0,
+                .output_container =
+                        {
+                                .buf = NULL,
+                                .buflen = 0,
+                                .line = NULL,
+                                .lines = 0,
+                        },
+        };
+        ssize_t ret;
+        while ((ret = read(fileDescriptor, tmpbuf, sizeof(tmpbuf))) > 0) {
+                size_t len = (size_t)ret;
+                result.output_container.buf =
+                        realloc(result.output_container.buf, result.output_container.buflen + len + 1);
+                memcpy(result.output_container.buf + result.output_container.buflen, tmpbuf, len);
+                result.output_container.buflen += len;
+        }
+
+        if (ret < 0) {
+                printf("read() returned %zd: %s\n", ret, strerror(errno));
+                result.error_code = -1;
+                return result;
+        }
+
+        /* some plugins may want to keep output unbroken, and some commands
+         * will yield no output, so return here for those */
+        if (flags & CMD_NO_ARRAYS || !result.output_container.buf || !result.output_container.buflen) {
+                return result;
+        }
+
+        /* and some may want both */
+        char *buf = NULL;
+        if (flags & CMD_NO_ASSOC) {
+                buf = malloc(result.output_container.buflen);
+                memcpy(buf, result.output_container.buf, result.output_container.buflen);
+        } else {
+                buf = result.output_container.buf;
+        }
+
+        result.output_container.line = NULL;
+        size_t ary_size = 0; /* rsf = right shift factor, dec'ed uncond once */
+        size_t rsf = 6;
+        size_t lineno = 0;
+        for (size_t i = 0; i < result.output_container.buflen;) {
+                /* make sure we have enough memory */
+                if (lineno >= ary_size) {
+                        /* ary_size must never be zero */
+                        do {
+                                ary_size = result.output_container.buflen >> --rsf;
+                        } while (!ary_size);
+
+                        result.output_container.line =
+                                realloc(result.output_container.line, ary_size * sizeof(char *));
+                }
+
+                /* set the pointer to the string */
+                result.output_container.line[lineno] = &buf[i];
+
+                /* hop to next newline or end of buffer */
+                while (buf[i] != '\n' && i < result.output_container.buflen) {
+                        i++;
+                }
+                buf[i] = '\0';
+
+                lineno++;
+                i++;
+        }
+
+        result.output_container.lines = lineno;
+
+        return result;
+}
+
 static int _cmd_fetch_output(int fileDescriptor, output *cmd_output, int flags) {
         char tmpbuf[4096];
         cmd_output->buf = NULL;
@@ -225,7 +379,6 @@ static int _cmd_fetch_output(int fileDescriptor, output *cmd_output, int flags)
         }
 
         cmd_output->line = NULL;
-        cmd_output->lens = NULL;
         size_t i = 0;
         size_t ary_size = 0; /* rsf = right shift factor, dec'ed uncond once */
         size_t rsf = 6;
@@ -239,7 +392,6 @@ static int _cmd_fetch_output(int fileDescriptor, output *cmd_output, int flags)
                         } while (!ary_size);
 
                         cmd_output->line = realloc(cmd_output->line, ary_size * sizeof(char *));
-                        cmd_output->lens = realloc(cmd_output->lens, ary_size * sizeof(size_t));
                 }
 
                 /* set the pointer to the string */
@@ -251,9 +403,6 @@ static int _cmd_fetch_output(int fileDescriptor, output *cmd_output, int flags)
                 }
                 buf[i] = '\0';
 
-                /* calculate the string length using pointer difference */
-                cmd_output->lens[lineno] = (size_t)&buf[i] - (size_t)cmd_output->line[lineno];
-
                 lineno++;
                 i++;
         }
@@ -336,6 +485,139 @@ int cmd_run(const char *cmdstring, output *out, output *err, int flags) {
         return cmd_run_array(argv, out, err, flags);
 }
 
+cmd_run_result cmd_run2(const char *cmd_string, int flags) {
+        cmd_run_result result = {
+                .cmd_error_code = 0,
+                .error_code = 0,
+                .stderr =
+                        {
+                                .buf = NULL,
+                                .buflen = 0,
+                                .line = NULL,
+                                .lines = 0,
+                        },
+                .stdout =
+                        {
+                                .buf = NULL,
+                                .buflen = 0,
+                                .line = NULL,
+                                .lines = 0,
+                        },
+        };
+
+        if (cmd_string == NULL) {
+                result.error_code = -1;
+                return result;
+        }
+
+        /* make copy of command string so strtok() doesn't silently modify it */
+        /* (the calling program may want to access it later) */
+        char *cmd = strdup(cmd_string);
+        if (cmd == NULL) {
+                result.error_code = -1;
+                return result;
+        }
+
+        /* This is not a shell, so we don't handle "???" */
+        if (strstr(cmd, "\"")) {
+                result.error_code = -1;
+                return result;
+        }
+
+        /* allow single quotes, but only if non-whitesapce doesn't occur on both sides */
+        if (strstr(cmd, " ' ") || strstr(cmd, "'''")) {
+                result.error_code = -1;
+                return result;
+        }
+
+        /* each arg must be whitespace-separated, so args can be a maximum
+         * of (len / 2) + 1. We add 1 extra to the mix for NULL termination */
+        size_t cmdlen = strlen(cmd_string);
+        size_t argc = (cmdlen >> 1) + 2;
+        char **argv = calloc(argc, sizeof(char *));
+
+        if (argv == NULL) {
+                printf("%s\n", _("Could not malloc argv array in popen()"));
+                result.error_code = -1;
+                return result;
+        }
+
+        /* get command arguments (stupidly, but fairly quickly) */
+        for (int i = 0; cmd; i++) {
+                char *str = cmd;
+                str += strspn(str, " \t\r\n"); /* trim any leading whitespace */
+
+                if (strstr(str, "'") == str) { /* handle SIMPLE quoted strings */
+                        str++;
+                        if (!strstr(str, "'")) {
+                                result.error_code = -1;
+                                return result; /* balanced? */
+                        }
+
+                        cmd = 1 + strstr(str, "'");
+                        str[strcspn(str, "'")] = 0;
+                } else {
+                        if (strpbrk(str, " \t\r\n")) {
+                                cmd = 1 + strpbrk(str, " \t\r\n");
+                                str[strcspn(str, " \t\r\n")] = 0;
+                        } else {
+                                cmd = NULL;
+                        }
+                }
+
+                if (cmd && strlen(cmd) == strspn(cmd, " \t\r\n")) {
+                        cmd = NULL;
+                }
+
+                argv[i++] = str;
+        }
+
+        result = cmd_run_array2(argv, flags);
+
+        return result;
+}
+
+cmd_run_result cmd_run_array2(char *const *cmd, int flags) {
+        cmd_run_result result = {
+                .cmd_error_code = 0,
+                .error_code = 0,
+                .stderr =
+                        {
+                                .buf = NULL,
+                                .buflen = 0,
+                                .line = NULL,
+                                .lines = 0,
+                        },
+                .stdout =
+                        {
+                                .buf = NULL,
+                                .buflen = 0,
+                                .line = NULL,
+                                .lines = 0,
+                        },
+        };
+
+        int_cmd_open_result cmd_open_result = _cmd_open2(cmd);
+        if (cmd_open_result.error_code != 0) {
+                // result.error_code = -1;
+                // return result;
+                // TODO properly handle this without dying
+                die(STATE_UNKNOWN, _("Could not open pipe: %s\n"), cmd[0]);
+        }
+
+        int file_descriptor = cmd_open_result.file_descriptor;
+        int pfd_out[2] = {cmd_open_result.stdout_pipe_fd[0], cmd_open_result.stdout_pipe_fd[1]};
+        int pfd_err[2] = {cmd_open_result.stderr_pipe_fd[0], cmd_open_result.stderr_pipe_fd[1]};
+
+        int_cmd_fetch_output2 tmp_stdout = _cmd_fetch_output2(pfd_out[0], flags);
+        result.stdout = tmp_stdout.output_container;
+        int_cmd_fetch_output2 tmp_stderr = _cmd_fetch_output2(pfd_err[0], flags);
+        result.stderr = tmp_stderr.output_container;
+
+        result.cmd_error_code = _cmd_close(file_descriptor);
+        return result;
+}
+
 int cmd_run_array(char *const *argv, output *out, output *err, int flags) {
         /* initialize the structs */
         if (out) {
diff --git a/lib/utils_cmd.h b/lib/utils_cmd.h
index 3672cdc9..d3a8f14f 100644
--- a/lib/utils_cmd.h
+++ b/lib/utils_cmd.h
@@ -13,7 +13,6 @@ typedef struct {
         char *buf;     /* output buffer */
         size_t buflen; /* output buffer content length */
         char **line;   /* array of lines (points to buf) */
-        size_t *lens;  /* string lengths */
         size_t lines;  /* lines of output */
 } output;
 
@@ -22,6 +21,15 @@ int cmd_run(const char *, output *, output *, int);
 int cmd_run_array(char *const *, output *, output *, int);
 int cmd_file_read(const char *, output *, int);
 
+typedef struct {
+ int error_code;
+ int cmd_error_code;
+ output stdout;
+ output stderr;
+} cmd_run_result;
+cmd_run_result cmd_run2(const char *cmd, int flags);
+cmd_run_result cmd_run_array2(char * const *cmd, int flags);
+
 /* only multi-threaded plugins need to bother with this */
 void cmd_init(void);
 #define CMD_INIT cmd_init()