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/* |
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* Copyright (C) 2002 Brad House <brad@mainstreetsoftworks.com> |
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* Distributed under the terms of the GNU General Public License, v2 or later |
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* Author: Brad House <brad@mainstreetsoftworks.com> |
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* |
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* $Header$ |
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* |
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*/ |
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|
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#include <errno.h> |
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#include <fcntl.h> |
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#include <signal.h> |
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#include <stdio.h> |
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#include <stdlib.h> |
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#include <limits.h> |
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#include <string.h> |
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#include <stdarg.h> |
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#include <sys/file.h> |
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#include <sys/stat.h> |
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#include <sys/time.h> |
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#include <sys/types.h> |
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#include <sys/resource.h> |
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#include <sys/wait.h> |
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#include <unistd.h> |
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#include <fcntl.h> |
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|
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#include <grp.h> |
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#include <pwd.h> |
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|
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#include "sandbox.h" |
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#include "config.h" |
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|
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/* BEGIN Prototypes */ |
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int file_security_check(char *filename); |
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/* END Prototypes */ |
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|
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/* glibc modified getcwd() functions */ |
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char *egetcwd(char *, size_t); |
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|
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char *get_sandbox_path(char *argv0) |
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{ |
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char path[255]; |
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char *cwd = NULL; |
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|
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memset(path, 0, sizeof(path)); |
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/* ARGV[0] specifies full path */ |
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if (argv0[0] == '/') { |
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strncpy(path, argv0, sizeof(path) - 1); |
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|
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/* ARGV[0] specifies relative path */ |
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} else { |
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egetcwd(cwd, sizeof(path) - 2); |
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snprintf(path, sizeof(path), "%s/%s", cwd, argv0); |
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if (cwd) |
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free(cwd); |
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cwd = NULL; |
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} |
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|
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/* Return just directory */ |
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return (sb_dirname(path)); |
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} |
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|
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char *get_sandbox_lib(char *sb_path) |
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{ |
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char path[255]; |
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|
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#ifdef SB_HAVE_64BIT_ARCH |
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snprintf(path, sizeof(path), "%s", LIB_NAME); |
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#else |
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snprintf(path, sizeof(path), "%s/%s", LIBSANDBOX_PATH, LIB_NAME); |
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if (file_exist(path, 0) <= 0) { |
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snprintf(path, sizeof(path), "%s%s", sb_path, LIB_NAME); |
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} |
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#endif |
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return (strdup(path)); |
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} |
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|
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char *get_sandbox_pids_file(void) |
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{ |
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if (0 < getenv("SANDBOX_PIDS_FILE")) { |
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return (strdup(getenv("SANDBOX_PIDS_FILE"))); |
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} |
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return (strdup(PIDS_FILE)); |
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} |
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|
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char *get_sandbox_rc(char *sb_path) |
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{ |
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char path[255]; |
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|
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snprintf(path, sizeof(path), "%s/%s", SANDBOX_BASHRC_PATH, BASHRC_NAME); |
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if (file_exist(path, 0) <= 0) { |
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snprintf(path, sizeof(path), "%s%s", sb_path, BASHRC_NAME); |
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} |
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return (strdup(path)); |
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} |
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|
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char *get_sandbox_log() |
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{ |
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char path[255]; |
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char *sandbox_log_env = NULL; |
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|
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/* THIS CHUNK BREAK THINGS BY DOING THIS: |
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* SANDBOX_LOG=/tmp/sandbox-app-admin/superadduser-1.0.7-11063.log |
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*/ |
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|
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sandbox_log_env = getenv(ENV_SANDBOX_LOG); |
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snprintf(path, sizeof(path) - 1, "%s%s%s%d%s", LOG_FILE_PREFIX, |
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(sandbox_log_env == NULL ? "" : sandbox_log_env), |
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(sandbox_log_env == NULL ? "" : "-"), getpid(), LOG_FILE_EXT); |
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return (strdup(path)); |
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} |
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|
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/* Obtain base directory name. Do not allow trailing / */ |
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char *sb_dirname(const char *path) |
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{ |
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char *ret = NULL; |
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char *ptr = NULL; |
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int loc = 0, i; |
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int cut_len = -1; |
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|
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/* don't think NULL will ever be passed, but just in case */ |
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if (NULL == path) |
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return (strdup(".")); |
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|
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/* Grab pointer to last slash */ |
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ptr = strrchr(path, '/'); |
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if (NULL == ptr) { |
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return (strdup(".")); |
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} |
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|
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/* decimal location of pointer */ |
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loc = ptr - path; |
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|
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/* Remove any trailing slash */ |
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for (i = loc - 1; i >= 0; i--) { |
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if (path[i] != '/') { |
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cut_len = i + 1; /* make cut_len the length of the string to keep */ |
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break; |
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} |
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} |
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|
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/* It could have been just a plain /, return a 1byte 0 filled string */ |
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if (-1 == cut_len) |
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return (strdup("")); |
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|
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/* Allocate memory, and return the directory */ |
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ret = (char *)malloc((cut_len + 1) * sizeof(char)); |
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memcpy(ret, path, cut_len); |
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ret[cut_len] = 0; |
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|
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return (ret); |
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} |
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|
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/* |
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char* dirname(const char* path) |
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{ |
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char* base = NULL; |
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unsigned int length = 0; |
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|
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base = strrchr(path, '/'); |
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if (NULL == base) |
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{ |
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return strdup("."); |
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} |
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while (base > path && *base == '/') |
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{ |
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base--; |
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} |
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length = (unsigned int) 1 + base - path; |
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|
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base = malloc(sizeof(char)*(length+1)); |
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memmove(base, path, length); |
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base[length] = 0; |
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|
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return base; |
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}*/ |
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|
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/* Convert text (string) modes to integer values */ |
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int file_getmode(char *mode) |
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{ |
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int mde = 0; |
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if (0 == strcasecmp(mode, "r+")) { |
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mde = O_RDWR | O_CREAT; |
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} else if (0 == strcasecmp(mode, "w+")) { |
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mde = O_RDWR | O_CREAT | O_TRUNC; |
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} else if (0 == strcasecmp(mode, "a+")) { |
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mde = O_RDWR | O_CREAT | O_APPEND; |
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} else if (0 == strcasecmp(mode, "r")) { |
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mde = O_RDONLY; |
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} else if (0 == strcasecmp(mode, "w")) { |
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mde = O_WRONLY | O_CREAT | O_TRUNC; |
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} else if (0 == strcasecmp(mode, "a")) { |
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mde = O_WRONLY | O_APPEND | O_CREAT; |
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} else { |
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mde = O_RDONLY; |
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} |
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return (mde); |
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} |
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|
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/* Get current position in file */ |
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long file_tell(int fp) |
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{ |
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return (lseek(fp, 0L, SEEK_CUR)); |
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} |
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|
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/* lock the file, preferrably the POSIX way */ |
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int file_lock(int fd, int lock, char *filename) |
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{ |
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int err; |
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#ifdef USE_FLOCK |
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if (flock(fd, lock) < 0) { |
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err = errno; |
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fprintf(stderr, ">>> %s flock file lock: %s\n", filename, strerror(err)); |
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return 0; |
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} |
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#else |
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struct flock fl; |
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fl.l_type = lock; |
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fl.l_whence = SEEK_SET; |
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fl.l_start = 0L; |
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fl.l_len = 0L; |
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fl.l_pid = getpid(); |
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if (fcntl(fd, F_SETLKW, &fl) < 0) { |
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err = errno; |
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fprintf(stderr, ">>> %s fcntl file lock: %s\n", filename, strerror(err)); |
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return 0; |
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} |
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#endif |
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return 1; |
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} |
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|
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/* unlock the file, preferrably the POSIX way */ |
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int file_unlock(int fd) |
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{ |
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#ifdef USE_FLOCK |
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if (flock(fd, LOCK_UN) < 0) { |
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perror(">>> flock file unlock"); |
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return 0; |
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} |
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#else |
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struct flock fl; |
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fl.l_type = F_UNLCK; |
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fl.l_whence = SEEK_SET; |
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fl.l_start = 0L; |
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fl.l_len = 0L; |
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fl.l_pid = getpid(); |
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if (fcntl(fd, F_SETLKW, &fl) < 0) { |
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perror(">>> fcntl file unlock"); |
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return 0; |
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} |
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#endif |
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return 1; |
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} |
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|
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/* Auto-determine from how the file was opened, what kind of lock to lock |
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* the file with |
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*/ |
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int file_locktype(char *mode) |
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{ |
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#ifdef USE_FLOCK |
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if (NULL != (strchr(mode, 'w')) || (NULL != strchr(mode, '+')) |
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|| (NULL != strchr(mode, 'a'))) |
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return (LOCK_EX); |
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return (LOCK_SH); |
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#else |
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if (NULL != (strchr(mode, 'w')) || (NULL != strchr(mode, '+')) |
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|| (NULL != strchr(mode, 'a'))) |
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return (F_WRLCK); |
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return (F_RDLCK); |
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#endif |
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} |
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|
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/* Use standard fopen style modes to open the specified file. Also auto-determines and |
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* locks the file either in shared or exclusive mode depending on opening mode |
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*/ |
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int file_open(char *filename, char *mode, int perm_specified, ...) |
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{ |
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int fd; |
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char error[250]; |
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va_list ap; |
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int perm; |
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char *group = NULL; |
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struct group *group_struct; |
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|
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file_security_check(filename); |
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|
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if (perm_specified) { |
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va_start(ap, perm_specified); |
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perm = va_arg(ap, int); |
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group = va_arg(ap, char *); |
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va_end(ap); |
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} |
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fd = open(filename, file_getmode(mode)); |
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file_security_check(filename); |
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if (-1 == fd) { |
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snprintf(error, sizeof(error), ">>> %s file mode: %s open", filename, mode); |
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perror(error); |
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return (fd); |
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} |
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if (perm_specified) { |
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if (fchmod(fd, 0664) && (0 == getuid())) { |
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snprintf(error, sizeof(error), ">>> Could not set mode: %s", filename); |
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perror(error); |
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} |
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} |
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if (NULL != group) { |
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group_struct = getgrnam(group); |
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if (NULL == group) { |
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snprintf(error, sizeof(error), ">>> Could not get grp number: %s", group); |
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perror(error); |
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} else { |
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if (fchown(fd, -1, group_struct->gr_gid) && (0 == getuid())) { |
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snprintf(error, sizeof(error), ">>> Could not set group: %s", filename); |
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perror(error); |
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} |
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} |
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} |
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/* Only lock the file if opening succeeded */ |
| 319 |
if (-1 != fd) { |
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if (file_security_check(filename) != 0) { |
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/* Security violation occured between the last check and the */ |
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/* creation of the file. As SpanKY pointed out there is a race */ |
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/* condition here, so if there is a problem here we'll mesg and */ |
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/* bail out to avoid it until we can work and test a better fix. */ |
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fprintf(stderr, "\n\nSECURITY RACE CONDITION: Problem recurred after creation!\nBAILING OUT\n\n"); |
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exit(127); |
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} |
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|
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if (0 == file_lock(fd, file_locktype(mode), filename)) { |
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close(fd); |
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return -1; |
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} |
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} else { |
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snprintf(error, sizeof(error), ">>> %s file mode:%s open", filename, mode); |
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perror(error); |
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} |
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return (fd); |
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} |
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|
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/* Close and unlock file */ |
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void file_close(int fd) |
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{ |
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if (-1 != fd) { |
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file_unlock(fd); |
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close(fd); |
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} |
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} |
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|
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/* Return length of file */ |
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long file_length(int fd) |
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{ |
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long pos, len; |
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pos = file_tell(fd); |
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len = lseek(fd, 0L, SEEK_END); |
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lseek(fd, pos, SEEK_SET); |
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return (len); |
| 357 |
} |
| 358 |
|
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/* Zero out file */ |
| 360 |
int file_truncate(int fd) |
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{ |
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lseek(fd, 0L, SEEK_SET); |
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if (ftruncate(fd, 0) < 0) { |
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perror(">>> file truncate"); |
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return 0; |
| 366 |
} |
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return 1; |
| 368 |
} |
| 369 |
|
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/* Check to see if a file exists Return: 1 success, 0 file not found, -1 error */ |
| 371 |
int file_exist(char *filename, int checkmode) |
| 372 |
{ |
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struct stat mystat; |
| 374 |
|
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/* Verify file exists and is regular file (not sym link) */ |
| 376 |
if (checkmode) { |
| 377 |
if (-1 == lstat(filename, &mystat)) { |
| 378 |
/* file doesn't exist */ |
| 379 |
if (ENOENT == errno) { |
| 380 |
return 0; |
| 381 |
} else { /* permission denied or other error */ |
| 382 |
perror(">>> stat file"); |
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return -1; |
| 384 |
} |
| 385 |
} |
| 386 |
if (!S_ISREG(mystat.st_mode)) |
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return -1; |
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|
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/* Just plain verify the file exists */ |
| 390 |
} else { |
| 391 |
if (-1 == stat(filename, &mystat)) { |
| 392 |
/* file does not exist */ |
| 393 |
if (ENOENT == errno) { |
| 394 |
return 0; |
| 395 |
} else { /* permission denied or other error */ |
| 396 |
perror(">>> stat file"); |
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return -1; |
| 398 |
} |
| 399 |
} |
| 400 |
} |
| 401 |
|
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return 1; |
| 403 |
} |
| 404 |
|
| 405 |
int file_security_check(char *filename) |
| 406 |
{ /* 0 == fine, >0 == problem */ |
| 407 |
struct stat stat_buf; |
| 408 |
struct group *group_buf; |
| 409 |
struct passwd *passwd_buf; |
| 410 |
|
| 411 |
passwd_buf = getpwnam("portage"); |
| 412 |
group_buf = getgrnam("portage"); |
| 413 |
|
| 414 |
if ((lstat(filename, &stat_buf) == -1) && (errno == ENOENT)) { |
| 415 |
/* Doesn't exist. */ |
| 416 |
return 0; |
| 417 |
} else { |
| 418 |
if ((stat_buf.st_nlink) > 1) { /* Security: We are handlinked... */ |
| 419 |
if (unlink(filename)) { |
| 420 |
fprintf(stderr, "Unable to delete file in security violation (hardlinked): %s\n", filename); |
| 421 |
exit(127); |
| 422 |
} |
| 423 |
fprintf(stderr, "File in security violation (hardlinked): %s\n", filename); |
| 424 |
return 1; |
| 425 |
} else if (S_ISLNK(stat_buf.st_mode)) { /* Security: We are a symlink? */ |
| 426 |
fprintf(stderr, "File in security violation (symlink): %s\n", filename); |
| 427 |
exit(127); |
| 428 |
} else if (0 == S_ISREG(stat_buf.st_mode)) { /* Security: special file */ |
| 429 |
fprintf(stderr, "File in security violation (not regular): %s\n", filename); |
| 430 |
exit(127); |
| 431 |
} else if (stat_buf.st_mode & S_IWOTH) { /* Security: We are o+w? */ |
| 432 |
if (unlink(filename)) { |
| 433 |
fprintf(stderr, "Unable to delete file in security violation (world write): %s\n", filename); |
| 434 |
exit(127); |
| 435 |
} |
| 436 |
fprintf(stderr, "File in security violation (world write): %s\n", filename); |
| 437 |
return 1; |
| 438 |
} else |
| 439 |
if (!((stat_buf.st_uid == 0) || (stat_buf.st_uid == getuid()) || |
| 440 |
((passwd_buf != NULL) && (stat_buf.st_uid == passwd_buf->pw_uid))) || |
| 441 |
!((stat_buf.st_gid == 0) || (stat_buf.st_gid == getgid()) || |
| 442 |
((group_buf != NULL) && (stat_buf.st_gid == group_buf->gr_gid)))) { |
| 443 |
/* Security: Owner/Group isn't right. */ |
| 444 |
|
| 445 |
/* uid = 0 or myuid or portage */ |
| 446 |
/* gid = 0 or mygid or portage */ |
| 447 |
|
| 448 |
if (0) { |
| 449 |
fprintf(stderr, "--1: %d,%d,%d,%d\n--2: %d,%d,%d,%d\n", |
| 450 |
(stat_buf.st_uid == 0), |
| 451 |
(stat_buf.st_uid == getuid()), |
| 452 |
(passwd_buf != NULL), |
| 453 |
(passwd_buf != NULL) ? (stat_buf.st_uid == passwd_buf->pw_uid) : -1, |
| 454 |
(stat_buf.st_gid == 0), |
| 455 |
(stat_buf.st_gid == getgid()), |
| 456 |
(group_buf != NULL), |
| 457 |
(group_buf != NULL) ? (stat_buf.st_gid == group_buf->gr_gid) : -1); |
| 458 |
} |
| 459 |
|
| 460 |
/* manpage: "The return value may point to static area" */ |
| 461 |
/* DO NOT ACTUALLY FREE THIS... It'll segfault. */ |
| 462 |
/* if(passwd_buf != NULL) { free(passwd_buf); } */ |
| 463 |
/* if(group_buf != NULL) { free(group_buf); } */ |
| 464 |
|
| 465 |
if (unlink(filename)) { |
| 466 |
fprintf(stderr, "Unable to delete file in security violation (bad owner/group): %s\n", filename); |
| 467 |
exit(127); |
| 468 |
} |
| 469 |
fprintf(stderr, "File in security violation (bad owner/group): %s\n", filename); |
| 470 |
return 1; |
| 471 |
} |
| 472 |
} /* Stat */ |
| 473 |
return 0; |
| 474 |
} |
| 475 |
|
| 476 |
// vim:noexpandtab noai:cindent ai |
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