[tor-commits] [tor/master] Extract functions from compat.c and util.h into a new fs library

commit 1e2e0f7e461b4518b123c4050c3dbc786ac422c4 Author: Nick Mathewson nickm@torproject.org Date: Wed Jun 27 09:40:21 2018 -0400

Extract functions from compat.c and util.h into a new fs library --- .gitignore | 2 + Makefile.am | 2 + src/common/compat.c | 556 -------------------------- src/common/compat.h | 50 +-- src/common/util.c | 1020 ----------------------------------------------- src/common/util.h | 84 +--- src/include.am | 1 + src/lib/fs/.may_include | 11 + src/lib/fs/dir.c | 360 +++++++++++++++++ src/lib/fs/dir.h | 27 ++ src/lib/fs/files.c | 711 +++++++++++++++++++++++++++++++++ src/lib/fs/files.h | 100 +++++ src/lib/fs/include.am | 25 ++ src/lib/fs/mmap.c | 234 +++++++++++ src/lib/fs/mmap.h | 35 ++ src/lib/fs/path.c | 289 ++++++++++++++ src/lib/fs/path.h | 24 ++ src/lib/fs/userdb.c | 132 ++++++ src/lib/fs/userdb.h | 20 + 19 files changed, 1979 insertions(+), 1704 deletions(-)

diff --git a/.gitignore b/.gitignore index 3c4c91e04..e38b9568c 100644 --- a/.gitignore +++ b/.gitignore @@ -175,6 +175,8 @@ uptime-*.json /src/lib/libtor-err-testing.a /src/lib/libtor-fdio.a /src/lib/libtor-fdio-testing.a +/src/lib/libtor-fs.a +/src/lib/libtor-fs-testing.a /src/lib/libtor-intmath.a /src/lib/libtor-intmath-testing.a /src/lib/libtor-lock.a diff --git a/Makefile.am b/Makefile.am index 97057048d..f43b2ad1f 100644 --- a/Makefile.am +++ b/Makefile.am @@ -40,6 +40,7 @@ endif # "Common" libraries used to link tor's utility code. TOR_UTIL_LIBS = \ src/common/libor.a \ + src/lib/libtor-fs.a \ src/lib/libtor-sandbox.a \ src/lib/libtor-net.a \ src/lib/libtor-log.a \ @@ -57,6 +58,7 @@ TOR_UTIL_LIBS = \ # and tests) TOR_UTIL_TESTING_LIBS = \ src/common/libor-testing.a \ + src/lib/libtor-fs-testing.a \ src/lib/libtor-sandbox-testing.a \ src/lib/libtor-net-testing.a \ src/lib/libtor-log-testing.a \ diff --git a/src/common/compat.c b/src/common/compat.c index b462ee1b4..e26591776 100644 --- a/src/common/compat.c +++ b/src/common/compat.c @@ -131,267 +131,6 @@ SecureZeroMemory(PVOID ptr, SIZE_T cnt) #include "lib/net/address.h" #include "lib/sandbox/sandbox.h"

-/** As open(path, flags, mode), but return an fd with the close-on-exec mode - * set. */ -int -tor_open_cloexec(const char *path, int flags, unsigned mode) -{ - int fd; - const char *p = sandbox_intern_string(path); -#ifdef O_CLOEXEC - fd = open(p, flags|O_CLOEXEC, mode); - if (fd >= 0) - return fd; - /* If we got an error, see if it is EINVAL. EINVAL might indicate that, - * even though we were built on a system with O_CLOEXEC support, we - * are running on one without. */ - if (errno != EINVAL) - return -1; -#endif /* defined(O_CLOEXEC) */ - - log_debug(LD_FS, "Opening %s with flags %x", p, flags); - fd = open(p, flags, mode); -#ifdef FD_CLOEXEC - if (fd >= 0) { - if (fcntl(fd, F_SETFD, FD_CLOEXEC) == -1) { - log_warn(LD_FS,"Couldn't set FD_CLOEXEC: %s", strerror(errno)); - close(fd); - return -1; - } - } -#endif /* defined(FD_CLOEXEC) */ - return fd; -} - -/** As fopen(path,mode), but ensures that the O_CLOEXEC bit is set on the - * underlying file handle. */ -FILE * -tor_fopen_cloexec(const char *path, const char *mode) -{ - FILE *result = fopen(path, mode); -#ifdef FD_CLOEXEC - if (result != NULL) { - if (fcntl(fileno(result), F_SETFD, FD_CLOEXEC) == -1) { - log_warn(LD_FS,"Couldn't set FD_CLOEXEC: %s", strerror(errno)); - fclose(result); - return NULL; - } - } -#endif /* defined(FD_CLOEXEC) */ - return result; -} - -/** As rename(), but work correctly with the sandbox. */ -int -tor_rename(const char *path_old, const char *path_new) -{ - log_debug(LD_FS, "Renaming %s to %s", path_old, path_new); - return rename(sandbox_intern_string(path_old), - sandbox_intern_string(path_new)); -} - -#if defined(HAVE_MMAP) || defined(RUNNING_DOXYGEN) -/** Try to create a memory mapping for <b>filename</b> and return it. On - * failure, return NULL. Sets errno properly, using ERANGE to mean - * "empty file". Must only be called on trusted Tor-owned files, as changing - * the underlying file's size causes unspecified behavior. */ -tor_mmap_t * -tor_mmap_file(const char *filename) -{ - int fd; /* router file */ - char *string; - int result; - tor_mmap_t *res; - size_t size, filesize; - struct stat st; - - tor_assert(filename); - - fd = tor_open_cloexec(filename, O_RDONLY, 0); - if (fd<0) { - int save_errno = errno; - int severity = (errno == ENOENT) ? LOG_INFO : LOG_WARN; - log_fn(severity, LD_FS,"Could not open "%s" for mmap(): %s",filename, - strerror(errno)); - errno = save_errno; - return NULL; - } - - /* Get the size of the file */ - result = fstat(fd, &st); - if (result != 0) { - int save_errno = errno; - log_warn(LD_FS, - "Couldn't fstat opened descriptor for "%s" during mmap: %s", - filename, strerror(errno)); - close(fd); - errno = save_errno; - return NULL; - } - size = filesize = (size_t)(st.st_size); - - if (st.st_size > SSIZE_T_CEILING || (off_t)size < st.st_size) { - log_warn(LD_FS, "File "%s" is too large. Ignoring.",filename); - errno = EFBIG; - close(fd); - return NULL; - } - if (!size) { - /* Zero-length file. If we call mmap on it, it will succeed but - * return NULL, and bad things will happen. So just fail. */ - log_info(LD_FS,"File "%s" is empty. Ignoring.",filename); - errno = ERANGE; - close(fd); - return NULL; - } - - string = mmap(0, size, PROT_READ, MAP_PRIVATE, fd, 0); - close(fd); - if (string == MAP_FAILED) { - int save_errno = errno; - log_warn(LD_FS,"Could not mmap file "%s": %s", filename, - strerror(errno)); - errno = save_errno; - return NULL; - } - - res = tor_malloc_zero(sizeof(tor_mmap_t)); - res->data = string; - res->size = filesize; - res->mapping_size = size; - - return res; -} -/** Release storage held for a memory mapping; returns 0 on success, - * or -1 on failure (and logs a warning). */ -int -tor_munmap_file(tor_mmap_t *handle) -{ - int res; - - if (handle == NULL) - return 0; - - res = munmap((char*)handle->data, handle->mapping_size); - if (res == 0) { - /* munmap() succeeded */ - tor_free(handle); - } else { - log_warn(LD_FS, "Failed to munmap() in tor_munmap_file(): %s", - strerror(errno)); - res = -1; - } - - return res; -} -#elif defined(_WIN32) -tor_mmap_t * -tor_mmap_file(const char *filename) -{ - TCHAR tfilename[MAX_PATH]= {0}; - tor_mmap_t *res = tor_malloc_zero(sizeof(tor_mmap_t)); - int empty = 0; - HANDLE file_handle = INVALID_HANDLE_VALUE; - DWORD size_low, size_high; - uint64_t real_size; - res->mmap_handle = NULL; -#ifdef UNICODE - mbstowcs(tfilename,filename,MAX_PATH); -#else - strlcpy(tfilename,filename,MAX_PATH); -#endif - file_handle = CreateFile(tfilename, - GENERIC_READ, FILE_SHARE_READ, - NULL, - OPEN_EXISTING, - FILE_ATTRIBUTE_NORMAL, - 0); - - if (file_handle == INVALID_HANDLE_VALUE) - goto win_err; - - size_low = GetFileSize(file_handle, &size_high); - - if (size_low == INVALID_FILE_SIZE && GetLastError() != NO_ERROR) { - log_warn(LD_FS,"Error getting size of "%s".",filename); - goto win_err; - } - if (size_low == 0 && size_high == 0) { - log_info(LD_FS,"File "%s" is empty. Ignoring.",filename); - empty = 1; - goto err; - } - real_size = (((uint64_t)size_high)<<32) | size_low; - if (real_size > SIZE_MAX) { - log_warn(LD_FS,"File "%s" is too big to map; not trying.",filename); - goto err; - } - res->size = real_size; - - res->mmap_handle = CreateFileMapping(file_handle, - NULL, - PAGE_READONLY, - size_high, - size_low, - NULL); - if (res->mmap_handle == NULL) - goto win_err; - res->data = (char*) MapViewOfFile(res->mmap_handle, - FILE_MAP_READ, - 0, 0, 0); - if (!res->data) - goto win_err; - - CloseHandle(file_handle); - return res; - win_err: { - DWORD e = GetLastError(); - int severity = (e == ERROR_FILE_NOT_FOUND || e == ERROR_PATH_NOT_FOUND) ? - LOG_INFO : LOG_WARN; - char *msg = format_win32_error(e); - log_fn(severity, LD_FS, "Couldn't mmap file "%s": %s", filename, msg); - tor_free(msg); - if (e == ERROR_FILE_NOT_FOUND || e == ERROR_PATH_NOT_FOUND) - errno = ENOENT; - else - errno = EINVAL; - } - err: - if (empty) - errno = ERANGE; - if (file_handle != INVALID_HANDLE_VALUE) - CloseHandle(file_handle); - tor_munmap_file(res); - return NULL; -} - -/* Unmap the file, and return 0 for success or -1 for failure */ -int -tor_munmap_file(tor_mmap_t *handle) -{ - if (handle == NULL) - return 0; - - if (handle->data) { - /* This is an ugly cast, but without it, "data" in struct tor_mmap_t would - have to be redefined as non-const. */ - BOOL ok = UnmapViewOfFile( (LPVOID) handle->data); - if (!ok) { - log_warn(LD_FS, "Failed to UnmapViewOfFile() in tor_munmap_file(): %d", - (int)GetLastError()); - } - } - - if (handle->mmap_handle != NULL) - CloseHandle(handle->mmap_handle); - tor_free(handle); - - return 0; -} -#else -#error "cannot implement tor_mmap_file" -#endif /* defined(HAVE_MMAP) || ... || ... */ - /** Given <b>hlen</b> bytes at <b>haystack</b> and <b>nlen</b> bytes at * <b>needle</b>, return a pointer to the first occurrence of the needle * within the haystack, or NULL if there is no such occurrence. @@ -553,45 +292,6 @@ set_uint64(void *cp, uint64_t v) memcpy(cp,&v,8); }

-/** - * Rename the file <b>from</b> to the file <b>to</b>. On Unix, this is - * the same as rename(2). On windows, this removes <b>to</b> first if - * it already exists. - * Returns 0 on success. Returns -1 and sets errno on failure. - */ -int -replace_file(const char *from, const char *to) -{ -#ifndef _WIN32 - return tor_rename(from, to); -#else - switch (file_status(to)) - { - case FN_NOENT: - break; - case FN_FILE: - case FN_EMPTY: - if (unlink(to)) return -1; - break; - case FN_ERROR: - return -1; - case FN_DIR: - errno = EISDIR; - return -1; - } - return tor_rename(from,to); -#endif /* !defined(_WIN32) */ -} - -/** Change <b>fname</b>'s modification time to now. */ -int -touch_file(const char *fname) -{ - if (utime(fname, NULL)!=0) - return -1; - return 0; -} - /** Represents a lockfile on which we hold the lock. */ struct tor_lockfile_t { /** Name of the file */ @@ -928,109 +628,6 @@ log_credential_status(void) } #endif /* !defined(_WIN32) */

-#ifndef _WIN32 -/** Cached struct from the last getpwname() call we did successfully. */ -static struct passwd *passwd_cached = NULL; - -/** Helper: copy a struct passwd object. - * - * We only copy the fields pw_uid, pw_gid, pw_name, pw_dir. Tor doesn't use - * any others, and I don't want to run into incompatibilities. - */ -static struct passwd * -tor_passwd_dup(const struct passwd *pw) -{ - struct passwd *new_pw = tor_malloc_zero(sizeof(struct passwd)); - if (pw->pw_name) - new_pw->pw_name = tor_strdup(pw->pw_name); - if (pw->pw_dir) - new_pw->pw_dir = tor_strdup(pw->pw_dir); - new_pw->pw_uid = pw->pw_uid; - new_pw->pw_gid = pw->pw_gid; - - return new_pw; -} - -#define tor_passwd_free(pw) \ - FREE_AND_NULL(struct passwd, tor_passwd_free_, (pw)) - -/** Helper: free one of our cached 'struct passwd' values. */ -static void -tor_passwd_free_(struct passwd *pw) -{ - if (!pw) - return; - - tor_free(pw->pw_name); - tor_free(pw->pw_dir); - tor_free(pw); -} - -/** Wrapper around getpwnam() that caches result. Used so that we don't need - * to give the sandbox access to /etc/passwd. - * - * The following fields alone will definitely be copied in the output: pw_uid, - * pw_gid, pw_name, pw_dir. Other fields are not present in cached values. - * - * When called with a NULL argument, this function clears storage associated - * with static variables it uses. - **/ -const struct passwd * -tor_getpwnam(const char *username) -{ - struct passwd *pw; - - if (username == NULL) { - tor_passwd_free(passwd_cached); - passwd_cached = NULL; - return NULL; - } - - if ((pw = getpwnam(username))) { - tor_passwd_free(passwd_cached); - passwd_cached = tor_passwd_dup(pw); - log_info(LD_GENERAL, "Caching new entry %s for %s", - passwd_cached->pw_name, username); - return pw; - } - - /* Lookup failed */ - if (! passwd_cached || ! passwd_cached->pw_name) - return NULL; - - if (! strcmp(username, passwd_cached->pw_name)) - return passwd_cached; // LCOV_EXCL_LINE - would need to make getpwnam flaky - - return NULL; -} - -/** Wrapper around getpwnam() that can use cached result from - * tor_getpwnam(). Used so that we don't need to give the sandbox access to - * /etc/passwd. - * - * The following fields alone will definitely be copied in the output: pw_uid, - * pw_gid, pw_name, pw_dir. Other fields are not present in cached values. - */ -const struct passwd * -tor_getpwuid(uid_t uid) -{ - struct passwd *pw; - - if ((pw = getpwuid(uid))) { - return pw; - } - - /* Lookup failed */ - if (! passwd_cached) - return NULL; - - if (uid == passwd_cached->pw_uid) - return passwd_cached; // LCOV_EXCL_LINE - would need to make getpwnam flaky - - return NULL; -} -#endif /* !defined(_WIN32) */ - /** Return true iff we were compiled with capability support, and capabilities * seem to work. **/ int @@ -1322,159 +919,6 @@ tor_disable_debugger_attach(void) return r; }

-#ifdef HAVE_PWD_H -/** Allocate and return a string containing the home directory for the - * user <b>username</b>. Only works on posix-like systems. */ -char * -get_user_homedir(const char *username) -{ - const struct passwd *pw; - tor_assert(username); - - if (!(pw = tor_getpwnam(username))) { - log_err(LD_CONFIG,"User "%s" not found.", username); - return NULL; - } - return tor_strdup(pw->pw_dir); -} -#endif /* defined(HAVE_PWD_H) */ - -/** Modify <b>fname</b> to contain the name of its parent directory. Doesn't - * actually examine the filesystem; does a purely syntactic modification. - * - * The parent of the root director is considered to be iteself. - * - * Path separators are the forward slash (/) everywhere and additionally - * the backslash () on Win32. - * - * Cuts off any number of trailing path separators but otherwise ignores - * them for purposes of finding the parent directory. - * - * Returns 0 if a parent directory was successfully found, -1 otherwise (fname - * did not have any path separators or only had them at the end). - * */ -int -get_parent_directory(char *fname) -{ - char *cp; - int at_end = 1; - tor_assert(fname); -#ifdef _WIN32 - /* If we start with, say, c:, then don't consider that the start of the path - */ - if (fname[0] && fname[1] == ':') { - fname += 2; - } -#endif /* defined(_WIN32) */ - /* Now we want to remove all path-separators at the end of the string, - * and to remove the end of the string starting with the path separator - * before the last non-path-separator. In perl, this would be - * s#[/]*$##; s#/[^/]*$##; - * on a unixy platform. - */ - cp = fname + strlen(fname); - at_end = 1; - while (--cp >= fname) { - int is_sep = (*cp == '/' -#ifdef _WIN32 - || *cp == '\' -#endif - ); - if (is_sep) { - if (cp == fname) { - /* This is the first separator in the file name; don't remove it! */ - cp[1] = '\0'; - return 0; - } - *cp = '\0'; - if (! at_end) - return 0; - } else { - at_end = 0; - } - } - return -1; -} - -#ifndef _WIN32 -/** Return a newly allocated string containing the output of getcwd(). Return - * NULL on failure. (We can't just use getcwd() into a PATH_MAX buffer, since - * Hurd hasn't got a PATH_MAX.) - */ -static char * -alloc_getcwd(void) -{ -#ifdef HAVE_GET_CURRENT_DIR_NAME - /* Glibc makes this nice and simple for us. */ - char *cwd = get_current_dir_name(); - char *result = NULL; - if (cwd) { - /* We make a copy here, in case tor_malloc() is not malloc(). */ - result = tor_strdup(cwd); - raw_free(cwd); // alias for free to avoid tripping check-spaces. - } - return result; -#else /* !(defined(HAVE_GET_CURRENT_DIR_NAME)) */ - size_t size = 1024; - char *buf = NULL; - char *ptr = NULL; - - while (ptr == NULL) { - buf = tor_realloc(buf, size); - ptr = getcwd(buf, size); - - if (ptr == NULL && errno != ERANGE) { - tor_free(buf); - return NULL; - } - - size *= 2; - } - return buf; -#endif /* defined(HAVE_GET_CURRENT_DIR_NAME) */ -} -#endif /* !defined(_WIN32) */ - -/** Expand possibly relative path <b>fname</b> to an absolute path. - * Return a newly allocated string, possibly equal to <b>fname</b>. */ -char * -make_path_absolute(char *fname) -{ -#ifdef _WIN32 - char *absfname_malloced = _fullpath(NULL, fname, 1); - - /* We don't want to assume that tor_free can free a string allocated - * with malloc. On failure, return fname (it's better than nothing). */ - char *absfname = tor_strdup(absfname_malloced ? absfname_malloced : fname); - if (absfname_malloced) raw_free(absfname_malloced); - - return absfname; -#else /* !(defined(_WIN32)) */ - char *absfname = NULL, *path = NULL; - - tor_assert(fname); - - if (fname[0] == '/') { - absfname = tor_strdup(fname); - } else { - path = alloc_getcwd(); - if (path) { - tor_asprintf(&absfname, "%s/%s", path, fname); - tor_free(path); - } else { - /* LCOV_EXCL_START Can't make getcwd fail. */ - /* If getcwd failed, the best we can do here is keep using the - * relative path. (Perhaps / isn't readable by this UID/GID.) */ - log_warn(LD_GENERAL, "Unable to find current working directory: %s", - strerror(errno)); - absfname = tor_strdup(fname); - /* LCOV_EXCL_STOP */ - } - } - return absfname; -#endif /* defined(_WIN32) */ -} - #ifndef HAVE__NSGETENVIRON #ifndef HAVE_EXTERN_ENVIRON_DECLARED /* Some platforms declare environ under some circumstances, others don't. */ diff --git a/src/common/compat.h b/src/common/compat.h index dd45f2246..1379f95a7 100644 --- a/src/common/compat.h +++ b/src/common/compat.h @@ -55,31 +55,13 @@ #include "lib/net/ipv4.h" #include "lib/net/ipv6.h" #include "lib/net/resolve.h" +#include "lib/fs/files.h" +#include "lib/fs/mmap.h" +#include "lib/fs/userdb.h"

#include <stdio.h> #include <errno.h>

-/* ===== Compiler compatibility */ - -/** Represents an mmaped file. Allocated via tor_mmap_file; freed with - * tor_munmap_file. */ -typedef struct tor_mmap_t { - const char *data; /**< Mapping of the file's contents. */ - size_t size; /**< Size of the file. */ - - /* None of the fields below should be accessed from outside compat.c */ -#ifdef HAVE_MMAP - size_t mapping_size; /**< Size of the actual mapping. (This is this file - * size, rounded up to the nearest page.) */ -#elif defined _WIN32 - HANDLE mmap_handle; -#endif /* defined(HAVE_MMAP) || ... */ - -} tor_mmap_t; - -tor_mmap_t *tor_mmap_file(const char *filename) ATTR_NONNULL((1)); -int tor_munmap_file(tor_mmap_t *handle) ATTR_NONNULL((1)); - const void *tor_memmem(const void *haystack, size_t hlen, const void *needle, size_t nlen) ATTR_NONNULL((1,3)); static const void *tor_memstr(const void *haystack, size_t hlen, @@ -145,26 +127,11 @@ struct tm *tor_gmtime_r(const time_t *timep, struct tm *result); #endif /* !defined(timercmp) */

/* ===== File compatibility */ -int tor_open_cloexec(const char *path, int flags, unsigned mode); -FILE *tor_fopen_cloexec(const char *path, const char *mode); -int tor_rename(const char *path_old, const char *path_new); - -int replace_file(const char *from, const char *to); -int touch_file(const char *fname); - typedef struct tor_lockfile_t tor_lockfile_t; tor_lockfile_t *tor_lockfile_lock(const char *filename, int blocking, int *locked_out); void tor_lockfile_unlock(tor_lockfile_t *lockfile);

-int64_t tor_get_avail_disk_space(const char *path); - -#ifdef _WIN32 -#define PATH_SEPARATOR "\" -#else -#define PATH_SEPARATOR "/" -#endif - /* ===== Net compatibility */

MOCK_DECL(int,tor_gethostname,(char *name, size_t namelen)); @@ -218,17 +185,6 @@ int have_capability_support(void); /** Flag for switch_id; see switch_id() for documentation */ #define SWITCH_ID_WARN_IF_NO_CAPS (1<<1) int switch_id(const char *user, unsigned flags); -#ifdef HAVE_PWD_H -char *get_user_homedir(const char *username); -#endif - -#ifndef _WIN32 -const struct passwd *tor_getpwnam(const char *username); -const struct passwd *tor_getpwuid(uid_t uid); -#endif - -int get_parent_directory(char *fname); -char *make_path_absolute(char *fname);

char **get_environment(void);

diff --git a/src/common/util.c b/src/common/util.c index 940f25e27..6233b8e4f 100644 --- a/src/common/util.c +++ b/src/common/util.c @@ -1076,851 +1076,10 @@ format_time_interval(char *out, size_t out_len, long interval) * File helpers * ===== */

-/** Write <b>count</b> bytes from <b>buf</b> to <b>fd</b>. Return the number - * of bytes written, or -1 on error. Only use if fd is a blocking fd. */ -ssize_t -write_all_to_fd(int fd, const char *buf, size_t count) -{ - size_t written = 0; - ssize_t result; - raw_assert(count < SSIZE_MAX); - - while (written != count) { - result = write(fd, buf+written, count-written); - if (result<0) - return -1; - written += result; - } - return (ssize_t)count; -} - -/** Read from <b>fd</b> to <b>buf</b>, until we get <b>count</b> bytes or - * reach the end of the file. Return the number of bytes read, or -1 on - * error. Only use if fd is a blocking fd. */ -ssize_t -read_all_from_fd(int fd, char *buf, size_t count) -{ - size_t numread = 0; - ssize_t result; - - if (count > SIZE_T_CEILING || count > SSIZE_MAX) { - errno = EINVAL; - return -1; - } - - while (numread < count) { - result = read(fd, buf+numread, count-numread); - if (result<0) - return -1; - else if (result == 0) - break; - numread += result; - } - return (ssize_t)numread; -} - /* * Filesystem operations. */

-/** Clean up <b>name</b> so that we can use it in a call to "stat". On Unix, - * we do nothing. On Windows, we remove a trailing slash, unless the path is - * the root of a disk. */ -static void -clean_name_for_stat(char *name) -{ -#ifdef _WIN32 - size_t len = strlen(name); - if (!len) - return; - if (name[len-1]=='\' || name[len-1]=='/') { - if (len == 1 || (len==3 && name[1]==':')) - return; - name[len-1]='\0'; - } -#else /* !(defined(_WIN32)) */ - (void)name; -#endif /* defined(_WIN32) */ -} - -/** Wrapper for unlink() to make it mockable for the test suite; returns 0 - * if unlinking the file succeeded, -1 and sets errno if unlinking fails. - */ - -MOCK_IMPL(int, -tor_unlink,(const char *pathname)) -{ - return unlink(pathname); -} - -/** Return: - * FN_ERROR if filename can't be read, is NULL, or is zero-length, - * FN_NOENT if it doesn't exist, - * FN_FILE if it is a non-empty regular file, or a FIFO on unix-like systems, - * FN_EMPTY for zero-byte regular files, - * FN_DIR if it's a directory, and - * FN_ERROR for any other file type. - * On FN_ERROR and FN_NOENT, sets errno. (errno is not set when FN_ERROR - * is returned due to an unhandled file type.) */ -file_status_t -file_status(const char *fname) -{ - struct stat st; - char *f; - int r; - if (!fname || strlen(fname) == 0) { - return FN_ERROR; - } - f = tor_strdup(fname); - clean_name_for_stat(f); - log_debug(LD_FS, "stat()ing %s", f); - r = stat(sandbox_intern_string(f), &st); - tor_free(f); - if (r) { - if (errno == ENOENT) { - return FN_NOENT; - } - return FN_ERROR; - } - if (st.st_mode & S_IFDIR) { - return FN_DIR; - } else if (st.st_mode & S_IFREG) { - if (st.st_size > 0) { - return FN_FILE; - } else if (st.st_size == 0) { - return FN_EMPTY; - } else { - return FN_ERROR; - } -#ifndef _WIN32 - } else if (st.st_mode & S_IFIFO) { - return FN_FILE; -#endif - } else { - return FN_ERROR; - } -} - -/** Check whether <b>dirname</b> exists and is private. If yes return 0. - * If <b>dirname</b> does not exist: - * - if <b>check</b>&CPD_CREATE, try to create it and return 0 on success. - * - if <b>check</b>&CPD_CHECK, and we think we can create it, return 0. - * - if <b>check</b>&CPD_CHECK is false, and the directory exists, return 0. - * - otherwise, return -1. - * If CPD_GROUP_OK is set, then it's okay if the directory - * is group-readable, but in all cases we create the directory mode 0700. - * If CPD_GROUP_READ is set, existing directory behaves as CPD_GROUP_OK and - * if the directory is created it will use mode 0750 with group read - * permission. Group read privileges also assume execute permission - * as norm for directories. If CPD_CHECK_MODE_ONLY is set, then we don't - * alter the directory permissions if they are too permissive: - * we just return -1. - * When effective_user is not NULL, check permissions against the given user - * and its primary group. - */ -MOCK_IMPL(int, -check_private_dir,(const char *dirname, cpd_check_t check, - const char *effective_user)) -{ - int r; - struct stat st; - - tor_assert(dirname); - -#ifndef _WIN32 - int fd; - const struct passwd *pw = NULL; - uid_t running_uid; - gid_t running_gid; - - /* - * Goal is to harden the implementation by removing any - * potential for race between stat() and chmod(). - * chmod() accepts filename as argument. If an attacker can move - * the file between stat() and chmod(), a potential race exists. - * - * Several suggestions taken from: - * https://developer.apple.com/library/mac/documentation/ - * Security/Conceptual/SecureCodingGuide/Articles/RaceConditions.html - */ - - /* Open directory. - * O_NOFOLLOW to ensure that it does not follow symbolic links */ - fd = open(sandbox_intern_string(dirname), O_NOFOLLOW); - - /* Was there an error? Maybe the directory does not exist? */ - if (fd == -1) { - - if (errno != ENOENT) { - /* Other directory error */ - log_warn(LD_FS, "Directory %s cannot be read: %s", dirname, - strerror(errno)); - return -1; - } - - /* Received ENOENT: Directory does not exist */ - - /* Should we create the directory? */ - if (check & CPD_CREATE) { - log_info(LD_GENERAL, "Creating directory %s", dirname); - if (check & CPD_GROUP_READ) { - r = mkdir(dirname, 0750); - } else { - r = mkdir(dirname, 0700); - } - - /* check for mkdir() error */ - if (r) { - log_warn(LD_FS, "Error creating directory %s: %s", dirname, - strerror(errno)); - return -1; - } - - /* we just created the directory. try to open it again. - * permissions on the directory will be checked again below.*/ - fd = open(sandbox_intern_string(dirname), O_NOFOLLOW); - - if (fd == -1) { - log_warn(LD_FS, "Could not reopen recently created directory %s: %s", - dirname, - strerror(errno)); - return -1; - } else { - close(fd); - } - - } else if (!(check & CPD_CHECK)) { - log_warn(LD_FS, "Directory %s does not exist.", dirname); - return -1; - } - - /* XXXX In the case where check==CPD_CHECK, we should look at the - * parent directory a little harder. */ - return 0; - } - - tor_assert(fd >= 0); - - //f = tor_strdup(dirname); - //clean_name_for_stat(f); - log_debug(LD_FS, "stat()ing %s", dirname); - //r = stat(sandbox_intern_string(f), &st); - r = fstat(fd, &st); - if (r == -1) { - log_warn(LD_FS, "fstat() on directory %s failed.", dirname); - close(fd); - return -1; - } - //tor_free(f); - - /* check that dirname is a directory */ - if (!(st.st_mode & S_IFDIR)) { - log_warn(LD_FS, "%s is not a directory", dirname); - close(fd); - return -1; - } - - if (effective_user) { - /* Look up the user and group information. - * If we have a problem, bail out. */ - pw = tor_getpwnam(effective_user); - if (pw == NULL) { - log_warn(LD_CONFIG, "Error setting configured user: %s not found", - effective_user); - close(fd); - return -1; - } - running_uid = pw->pw_uid; - running_gid = pw->pw_gid; - } else { - running_uid = getuid(); - running_gid = getgid(); - } - if (st.st_uid != running_uid) { - char *process_ownername = NULL, *file_ownername = NULL; - - { - const struct passwd *pw_running = tor_getpwuid(running_uid); - process_ownername = pw_running ? tor_strdup(pw_running->pw_name) : - tor_strdup("<unknown>"); - } - - { - const struct passwd *pw_stat = tor_getpwuid(st.st_uid); - file_ownername = pw_stat ? tor_strdup(pw_stat->pw_name) : - tor_strdup("<unknown>"); - } - - log_warn(LD_FS, "%s is not owned by this user (%s, %d) but by " - "%s (%d). Perhaps you are running Tor as the wrong user?", - dirname, process_ownername, (int)running_uid, - file_ownername, (int)st.st_uid); - - tor_free(process_ownername); - tor_free(file_ownername); - close(fd); - return -1; - } - if ( (check & (CPD_GROUP_OK|CPD_GROUP_READ)) - && (st.st_gid != running_gid) && (st.st_gid != 0)) { - struct group *gr; - char *process_groupname = NULL; - gr = getgrgid(running_gid); - process_groupname = gr ? tor_strdup(gr->gr_name) : tor_strdup("<unknown>"); - gr = getgrgid(st.st_gid); - - log_warn(LD_FS, "%s is not owned by this group (%s, %d) but by group " - "%s (%d). Are you running Tor as the wrong user?", - dirname, process_groupname, (int)running_gid, - gr ? gr->gr_name : "<unknown>", (int)st.st_gid); - - tor_free(process_groupname); - close(fd); - return -1; - } - unsigned unwanted_bits = 0; - if (check & (CPD_GROUP_OK|CPD_GROUP_READ)) { - unwanted_bits = 0027; - } else { - unwanted_bits = 0077; - } - unsigned check_bits_filter = ~0; - if (check & CPD_RELAX_DIRMODE_CHECK) { - check_bits_filter = 0022; - } - if ((st.st_mode & unwanted_bits & check_bits_filter) != 0) { - unsigned new_mode; - if (check & CPD_CHECK_MODE_ONLY) { - log_warn(LD_FS, "Permissions on directory %s are too permissive.", - dirname); - close(fd); - return -1; - } - log_warn(LD_FS, "Fixing permissions on directory %s", dirname); - new_mode = st.st_mode; - new_mode |= 0700; /* Owner should have rwx */ - if (check & CPD_GROUP_READ) { - new_mode |= 0050; /* Group should have rx */ - } - new_mode &= ~unwanted_bits; /* Clear the bits that we didn't want set...*/ - if (fchmod(fd, new_mode)) { - log_warn(LD_FS, "Could not chmod directory %s: %s", dirname, - strerror(errno)); - close(fd); - return -1; - } else { - close(fd); - return 0; - } - } - close(fd); -#else /* !(!defined(_WIN32)) */ - /* Win32 case: we can't open() a directory. */ - (void)effective_user; - - char *f = tor_strdup(dirname); - clean_name_for_stat(f); - log_debug(LD_FS, "stat()ing %s", f); - r = stat(sandbox_intern_string(f), &st); - tor_free(f); - if (r) { - if (errno != ENOENT) { - log_warn(LD_FS, "Directory %s cannot be read: %s", dirname, - strerror(errno)); - return -1; - } - if (check & CPD_CREATE) { - log_info(LD_GENERAL, "Creating directory %s", dirname); - r = mkdir(dirname); - if (r) { - log_warn(LD_FS, "Error creating directory %s: %s", dirname, - strerror(errno)); - return -1; - } - } else if (!(check & CPD_CHECK)) { - log_warn(LD_FS, "Directory %s does not exist.", dirname); - return -1; - } - return 0; - } - if (!(st.st_mode & S_IFDIR)) { - log_warn(LD_FS, "%s is not a directory", dirname); - return -1; - } - -#endif /* !defined(_WIN32) */ - return 0; -} - -/** Create a file named <b>fname</b> with the contents <b>str</b>. Overwrite - * the previous <b>fname</b> if possible. Return 0 on success, -1 on failure. - * - * This function replaces the old file atomically, if possible. This - * function, and all other functions in util.c that create files, create them - * with mode 0600. - */ -MOCK_IMPL(int, -write_str_to_file,(const char *fname, const char *str, int bin)) -{ -#ifdef _WIN32 - if (!bin && strchr(str, '\r')) { - log_warn(LD_BUG, - "We're writing a text string that already contains a CR to %s", - escaped(fname)); - } -#endif /* defined(_WIN32) */ - return write_bytes_to_file(fname, str, strlen(str), bin); -} - -/** Represents a file that we're writing to, with support for atomic commit: - * we can write into a temporary file, and either remove the file on - * failure, or replace the original file on success. */ -struct open_file_t { - char *tempname; /**< Name of the temporary file. */ - char *filename; /**< Name of the original file. */ - unsigned rename_on_close:1; /**< Are we using the temporary file or not? */ - unsigned binary:1; /**< Did we open in binary mode? */ - int fd; /**< fd for the open file. */ - FILE *stdio_file; /**< stdio wrapper for <b>fd</b>. */ -}; - -/** Try to start writing to the file in <b>fname</b>, passing the flags - * <b>open_flags</b> to the open() syscall, creating the file (if needed) with - * access value <b>mode</b>. If the O_APPEND flag is set, we append to the - * original file. Otherwise, we open a new temporary file in the same - * directory, and either replace the original or remove the temporary file - * when we're done. - * - * Return the fd for the newly opened file, and store working data in - * *<b>data_out</b>. The caller should not close the fd manually: - * instead, call finish_writing_to_file() or abort_writing_to_file(). - * Returns -1 on failure. - * - * NOTE: When not appending, the flags O_CREAT and O_TRUNC are treated - * as true and the flag O_EXCL is treated as false. - * - * NOTE: Ordinarily, O_APPEND means "seek to the end of the file before each - * write()". We don't do that. - */ -int -start_writing_to_file(const char *fname, int open_flags, int mode, - open_file_t **data_out) -{ - open_file_t *new_file = tor_malloc_zero(sizeof(open_file_t)); - const char *open_name; - int append = 0; - - tor_assert(fname); - tor_assert(data_out); -#if (O_BINARY != 0 && O_TEXT != 0) - tor_assert((open_flags & (O_BINARY|O_TEXT)) != 0); -#endif - new_file->fd = -1; - new_file->filename = tor_strdup(fname); - if (open_flags & O_APPEND) { - open_name = fname; - new_file->rename_on_close = 0; - append = 1; - open_flags &= ~O_APPEND; - } else { - tor_asprintf(&new_file->tempname, "%s.tmp", fname); - open_name = new_file->tempname; - /* We always replace an existing temporary file if there is one. */ - open_flags |= O_CREAT|O_TRUNC; - open_flags &= ~O_EXCL; - new_file->rename_on_close = 1; - } -#if O_BINARY != 0 - if (open_flags & O_BINARY) - new_file->binary = 1; -#endif - - new_file->fd = tor_open_cloexec(open_name, open_flags, mode); - if (new_file->fd < 0) { - log_warn(LD_FS, "Couldn't open "%s" (%s) for writing: %s", - open_name, fname, strerror(errno)); - goto err; - } - if (append) { - if (tor_fd_seekend(new_file->fd) < 0) { - log_warn(LD_FS, "Couldn't seek to end of file "%s": %s", open_name, - strerror(errno)); - goto err; - } - } - - *data_out = new_file; - - return new_file->fd; - - err: - if (new_file->fd >= 0) - close(new_file->fd); - *data_out = NULL; - tor_free(new_file->filename); - tor_free(new_file->tempname); - tor_free(new_file); - return -1; -} - -/** Given <b>file_data</b> from start_writing_to_file(), return a stdio FILE* - * that can be used to write to the same file. The caller should not mix - * stdio calls with non-stdio calls. */ -FILE * -fdopen_file(open_file_t *file_data) -{ - tor_assert(file_data); - if (file_data->stdio_file) - return file_data->stdio_file; - tor_assert(file_data->fd >= 0); - if (!(file_data->stdio_file = fdopen(file_data->fd, - file_data->binary?"ab":"a"))) { - log_warn(LD_FS, "Couldn't fdopen "%s" [%d]: %s", file_data->filename, - file_data->fd, strerror(errno)); - } - return file_data->stdio_file; -} - -/** Combines start_writing_to_file with fdopen_file(): arguments are as - * for start_writing_to_file, but */ -FILE * -start_writing_to_stdio_file(const char *fname, int open_flags, int mode, - open_file_t **data_out) -{ - FILE *res; - if (start_writing_to_file(fname, open_flags, mode, data_out)<0) - return NULL; - if (!(res = fdopen_file(*data_out))) { - abort_writing_to_file(*data_out); - *data_out = NULL; - } - return res; -} - -/** Helper function: close and free the underlying file and memory in - * <b>file_data</b>. If we were writing into a temporary file, then delete - * that file (if abort_write is true) or replaces the target file with - * the temporary file (if abort_write is false). */ -static int -finish_writing_to_file_impl(open_file_t *file_data, int abort_write) -{ - int r = 0; - - tor_assert(file_data && file_data->filename); - if (file_data->stdio_file) { - if (fclose(file_data->stdio_file)) { - log_warn(LD_FS, "Error closing "%s": %s", file_data->filename, - strerror(errno)); - abort_write = r = -1; - } - } else if (file_data->fd >= 0 && close(file_data->fd) < 0) { - log_warn(LD_FS, "Error flushing "%s": %s", file_data->filename, - strerror(errno)); - abort_write = r = -1; - } - - if (file_data->rename_on_close) { - tor_assert(file_data->tempname && file_data->filename); - if (!abort_write) { - tor_assert(strcmp(file_data->filename, file_data->tempname)); - if (replace_file(file_data->tempname, file_data->filename)) { - log_warn(LD_FS, "Error replacing "%s": %s", file_data->filename, - strerror(errno)); - abort_write = r = -1; - } - } - if (abort_write) { - int res = unlink(file_data->tempname); - if (res != 0) { - /* We couldn't unlink and we'll leave a mess behind */ - log_warn(LD_FS, "Failed to unlink %s: %s", - file_data->tempname, strerror(errno)); - r = -1; - } - } - } - - tor_free(file_data->filename); - tor_free(file_data->tempname); - tor_free(file_data); - - return r; -} - -/** Finish writing to <b>file_data</b>: close the file handle, free memory as - * needed, and if using a temporary file, replace the original file with - * the temporary file. */ -int -finish_writing_to_file(open_file_t *file_data) -{ - return finish_writing_to_file_impl(file_data, 0); -} - -/** Finish writing to <b>file_data</b>: close the file handle, free memory as - * needed, and if using a temporary file, delete it. */ -int -abort_writing_to_file(open_file_t *file_data) -{ - return finish_writing_to_file_impl(file_data, 1); -} - -/** Helper: given a set of flags as passed to open(2), open the file - * <b>fname</b> and write all the sized_chunk_t structs in <b>chunks</b> to - * the file. Do so as atomically as possible e.g. by opening temp files and - * renaming. */ -static int -write_chunks_to_file_impl(const char *fname, const smartlist_t *chunks, - int open_flags) -{ - open_file_t *file = NULL; - int fd; - ssize_t result; - fd = start_writing_to_file(fname, open_flags, 0600, &file); - if (fd<0) - return -1; - SMARTLIST_FOREACH(chunks, sized_chunk_t *, chunk, - { - result = write_all(fd, chunk->bytes, chunk->len, 0); - if (result < 0) { - log_warn(LD_FS, "Error writing to "%s": %s", fname, - strerror(errno)); - goto err; - } - tor_assert((size_t)result == chunk->len); - }); - - return finish_writing_to_file(file); - err: - abort_writing_to_file(file); - return -1; -} - -/** Given a smartlist of sized_chunk_t, write them to a file - * <b>fname</b>, overwriting or creating the file as necessary. - * If <b>no_tempfile</b> is 0 then the file will be written - * atomically. */ -int -write_chunks_to_file(const char *fname, const smartlist_t *chunks, int bin, - int no_tempfile) -{ - int flags = OPEN_FLAGS_REPLACE|(bin?O_BINARY:O_TEXT); - - if (no_tempfile) { - /* O_APPEND stops write_chunks_to_file from using tempfiles */ - flags |= O_APPEND; - } - return write_chunks_to_file_impl(fname, chunks, flags); -} - -/** Write <b>len</b> bytes, starting at <b>str</b>, to <b>fname</b> - using the open() flags passed in <b>flags</b>. */ -static int -write_bytes_to_file_impl(const char *fname, const char *str, size_t len, - int flags) -{ - int r; - sized_chunk_t c = { str, len }; - smartlist_t *chunks = smartlist_new(); - smartlist_add(chunks, &c); - r = write_chunks_to_file_impl(fname, chunks, flags); - smartlist_free(chunks); - return r; -} - -/** As write_str_to_file, but does not assume a NUL-terminated - * string. Instead, we write <b>len</b> bytes, starting at <b>str</b>. */ -MOCK_IMPL(int, -write_bytes_to_file,(const char *fname, const char *str, size_t len, - int bin)) -{ - return write_bytes_to_file_impl(fname, str, len, - OPEN_FLAGS_REPLACE|(bin?O_BINARY:O_TEXT)); -} - -/** As write_bytes_to_file, but if the file already exists, append the bytes - * to the end of the file instead of overwriting it. */ -int -append_bytes_to_file(const char *fname, const char *str, size_t len, - int bin) -{ - return write_bytes_to_file_impl(fname, str, len, - OPEN_FLAGS_APPEND|(bin?O_BINARY:O_TEXT)); -} - -/** Like write_str_to_file(), but also return -1 if there was a file - already residing in <b>fname</b>. */ -int -write_bytes_to_new_file(const char *fname, const char *str, size_t len, - int bin) -{ - return write_bytes_to_file_impl(fname, str, len, - OPEN_FLAGS_DONT_REPLACE| - (bin?O_BINARY:O_TEXT)); -} - -/** - * Read the contents of the open file <b>fd</b> presuming it is a FIFO - * (or similar) file descriptor for which the size of the file isn't - * known ahead of time. Return NULL on failure, and a NUL-terminated - * string on success. On success, set <b>sz_out</b> to the number of - * bytes read. - */ -char * -read_file_to_str_until_eof(int fd, size_t max_bytes_to_read, size_t *sz_out) -{ - ssize_t r; - size_t pos = 0; - char *string = NULL; - size_t string_max = 0; - - if (max_bytes_to_read+1 >= SIZE_T_CEILING) { - errno = EINVAL; - return NULL; - } - - do { - /* XXXX This "add 1K" approach is a little goofy; if we care about - * performance here, we should be doubling. But in practice we shouldn't - * be using this function on big files anyway. */ - string_max = pos + 1024; - if (string_max > max_bytes_to_read) - string_max = max_bytes_to_read + 1; - string = tor_realloc(string, string_max); - r = read(fd, string + pos, string_max - pos - 1); - if (r < 0) { - int save_errno = errno; - tor_free(string); - errno = save_errno; - return NULL; - } - - pos += r; - } while (r > 0 && pos < max_bytes_to_read); - - tor_assert(pos < string_max); - *sz_out = pos; - string[pos] = '\0'; - return string; -} - -/** Read the contents of <b>filename</b> into a newly allocated - * string; return the string on success or NULL on failure. - * - * If <b>stat_out</b> is provided, store the result of stat()ing the - * file into <b>stat_out</b>. - * - * If <b>flags</b> &amp; RFTS_BIN, open the file in binary mode. - * If <b>flags</b> &amp; RFTS_IGNORE_MISSING, don't warn if the file - * doesn't exist. - */ -/* - * This function <em>may</em> return an erroneous result if the file - * is modified while it is running, but must not crash or overflow. - * Right now, the error case occurs when the file length grows between - * the call to stat and the call to read_all: the resulting string will - * be truncated. - */ -MOCK_IMPL(char *, -read_file_to_str, (const char *filename, int flags, struct stat *stat_out)) -{ - int fd; /* router file */ - struct stat statbuf; - char *string; - ssize_t r; - int bin = flags & RFTS_BIN; - - tor_assert(filename); - - fd = tor_open_cloexec(filename,O_RDONLY|(bin?O_BINARY:O_TEXT),0); - if (fd<0) { - int severity = LOG_WARN; - int save_errno = errno; - if (errno == ENOENT && (flags & RFTS_IGNORE_MISSING)) - severity = LOG_INFO; - log_fn(severity, LD_FS,"Could not open "%s": %s",filename, - strerror(errno)); - errno = save_errno; - return NULL; - } - - if (fstat(fd, &statbuf)<0) { - int save_errno = errno; - close(fd); - log_warn(LD_FS,"Could not fstat "%s".",filename); - errno = save_errno; - return NULL; - } - -#ifndef _WIN32 -/** When we detect that we're reading from a FIFO, don't read more than - * this many bytes. It's insane overkill for most uses. */ -#define FIFO_READ_MAX (1024*1024) - if (S_ISFIFO(statbuf.st_mode)) { - size_t sz = 0; - string = read_file_to_str_until_eof(fd, FIFO_READ_MAX, &sz); - int save_errno = errno; - if (string && stat_out) { - statbuf.st_size = sz; - memcpy(stat_out, &statbuf, sizeof(struct stat)); - } - close(fd); - if (!string) - errno = save_errno; - return string; - } -#endif /* !defined(_WIN32) */ - - if ((uint64_t)(statbuf.st_size)+1 >= SIZE_T_CEILING) { - close(fd); - errno = EINVAL; - return NULL; - } - - string = tor_malloc((size_t)(statbuf.st_size+1)); - - r = read_all(fd,string,(size_t)statbuf.st_size,0); - if (r<0) { - int save_errno = errno; - log_warn(LD_FS,"Error reading from file "%s": %s", filename, - strerror(errno)); - tor_free(string); - close(fd); - errno = save_errno; - return NULL; - } - string[r] = '\0'; /* NUL-terminate the result. */ - -#if defined(_WIN32) || defined(__CYGWIN__) - if (!bin && strchr(string, '\r')) { - log_debug(LD_FS, "We didn't convert CRLF to LF as well as we hoped " - "when reading %s. Coping.", - filename); - tor_strstrip(string, "\r"); - r = strlen(string); - } - if (!bin) { - statbuf.st_size = (size_t) r; - } else -#endif /* defined(_WIN32) || defined(__CYGWIN__) */ - if (r != statbuf.st_size) { - /* Unless we're using text mode on win32, we'd better have an exact - * match for size. */ - int save_errno = errno; - log_warn(LD_FS,"Could read only %d of %ld bytes of file "%s".", - (int)r, (long)statbuf.st_size,filename); - tor_free(string); - close(fd); - errno = save_errno; - return NULL; - } - close(fd); - if (stat_out) { - memcpy(stat_out, &statbuf, sizeof(struct stat)); - } - - return string; -} - #define TOR_ISODIGIT(c) ('0' <= (c) && (c) <= '7')

/** Given a c-style double-quoted escaped string in <b>s</b>, extract and @@ -2040,185 +1199,6 @@ unescape_string(const char *s, char **result, size_t *size_out) } }

-/** Removes enclosing quotes from <b>path</b> and unescapes quotes between the - * enclosing quotes. Backslashes are not unescaped. Return the unquoted - * <b>path</b> on success or 0 if <b>path</b> is not quoted correctly. */ -char * -get_unquoted_path(const char *path) -{ - size_t len = strlen(path); - - if (len == 0) { - return tor_strdup(""); - } - - int has_start_quote = (path[0] == '"'); - int has_end_quote = (len > 0 && path[len-1] == '"'); - if (has_start_quote != has_end_quote || (len == 1 && has_start_quote)) { - return NULL; - } - - char *unquoted_path = tor_malloc(len - has_start_quote - has_end_quote + 1); - char *s = unquoted_path; - size_t i; - for (i = has_start_quote; i < len - has_end_quote; i++) { - if (path[i] == '"' && (i > 0 && path[i-1] == '\')) { - *(s-1) = path[i]; - } else if (path[i] != '"') { - *s++ = path[i]; - } else { /* unescaped quote */ - tor_free(unquoted_path); - return NULL; - } - } - *s = '\0'; - return unquoted_path; -} - -/** Expand any homedir prefix on <b>filename</b>; return a newly allocated - * string. */ -char * -expand_filename(const char *filename) -{ - tor_assert(filename); -#ifdef _WIN32 - /* Might consider using GetFullPathName() as described here: - * http://etutorials.org/Programming/secure+programming/ - * Chapter+3.+Input+Validation/3.7+Validating+Filenames+and+Paths/ - */ - return tor_strdup(filename); -#else /* !(defined(_WIN32)) */ - if (*filename == '~') { - char *home, *result=NULL; - const char *rest; - - if (filename[1] == '/' || filename[1] == '\0') { - home = getenv("HOME"); - if (!home) { - log_warn(LD_CONFIG, "Couldn't find $HOME environment variable while " - "expanding "%s"; defaulting to "".", filename); - home = tor_strdup(""); - } else { - home = tor_strdup(home); - } - rest = strlen(filename)>=2?(filename+2):""; - } else { -#ifdef HAVE_PWD_H - char *username, *slash; - slash = strchr(filename, '/'); - if (slash) - username = tor_strndup(filename+1,slash-filename-1); - else - username = tor_strdup(filename+1); - if (!(home = get_user_homedir(username))) { - log_warn(LD_CONFIG,"Couldn't get homedir for "%s"",username); - tor_free(username); - return NULL; - } - tor_free(username); - rest = slash ? (slash+1) : ""; -#else /* !(defined(HAVE_PWD_H)) */ - log_warn(LD_CONFIG, "Couldn't expand homedir on system without pwd.h"); - return tor_strdup(filename); -#endif /* defined(HAVE_PWD_H) */ - } - tor_assert(home); - /* Remove trailing slash. */ - if (strlen(home)>1 && !strcmpend(home,PATH_SEPARATOR)) { - home[strlen(home)-1] = '\0'; - } - tor_asprintf(&result,"%s"PATH_SEPARATOR"%s",home,rest); - tor_free(home); - return result; - } else { - return tor_strdup(filename); - } -#endif /* defined(_WIN32) */ -} - -/** Return a new list containing the filenames in the directory <b>dirname</b>. - * Return NULL on error or if <b>dirname</b> is not a directory. - */ -MOCK_IMPL(smartlist_t *, -tor_listdir, (const char *dirname)) -{ - smartlist_t *result; -#ifdef _WIN32 - char *pattern=NULL; - TCHAR tpattern[MAX_PATH] = {0}; - char name[MAX_PATH*2+1] = {0}; - HANDLE handle; - WIN32_FIND_DATA findData; - tor_asprintf(&pattern, "%s\*", dirname); -#ifdef UNICODE - mbstowcs(tpattern,pattern,MAX_PATH); -#else - strlcpy(tpattern, pattern, MAX_PATH); -#endif - if (INVALID_HANDLE_VALUE == (handle = FindFirstFile(tpattern, &findData))) { - tor_free(pattern); - return NULL; - } - result = smartlist_new(); - while (1) { -#ifdef UNICODE - wcstombs(name,findData.cFileName,MAX_PATH); - name[sizeof(name)-1] = '\0'; -#else - strlcpy(name,findData.cFileName,sizeof(name)); -#endif /* defined(UNICODE) */ - if (strcmp(name, ".") && - strcmp(name, "..")) { - smartlist_add_strdup(result, name); - } - if (!FindNextFile(handle, &findData)) { - DWORD err; - if ((err = GetLastError()) != ERROR_NO_MORE_FILES) { - char *errstr = format_win32_error(err); - log_warn(LD_FS, "Error reading directory '%s': %s", dirname, errstr); - tor_free(errstr); - } - break; - } - } - FindClose(handle); - tor_free(pattern); -#else /* !(defined(_WIN32)) */ - const char *prot_dname = sandbox_intern_string(dirname); - DIR *d; - struct dirent *de; - if (!(d = opendir(prot_dname))) - return NULL; - - result = smartlist_new(); - while ((de = readdir(d))) { - if (!strcmp(de->d_name, ".") || - !strcmp(de->d_name, "..")) - continue; - smartlist_add_strdup(result, de->d_name); - } - closedir(d); -#endif /* defined(_WIN32) */ - return result; -} - -/** Return true iff <b>filename</b> is a relative path. */ -int -path_is_relative(const char *filename) -{ - if (filename && filename[0] == '/') - return 0; -#ifdef _WIN32 - else if (filename && filename[0] == '\') - return 0; - else if (filename && strlen(filename)>3 && TOR_ISALPHA(filename[0]) && - filename[1] == ':' && filename[2] == '\') - return 0; -#endif /* defined(_WIN32) */ - else - return 1; -} - /* ===== * Process helpers * ===== */ diff --git a/src/common/util.h b/src/common/util.h index b7ac2a176..4f8d6395d 100644 --- a/src/common/util.h +++ b/src/common/util.h @@ -35,16 +35,9 @@ #include "lib/log/ratelim.h" #include "lib/log/util_bug.h" #include "lib/log/escape.h" - -#ifndef O_BINARY -#define O_BINARY 0 -#endif -#ifndef O_TEXT -#define O_TEXT 0 -#endif -#ifndef O_NOFOLLOW -#define O_NOFOLLOW 0 -#endif +#include "lib/fs/dir.h" +#include "lib/fs/files.h" +#include "lib/fs/path.h"

uint64_t tor_htonll(uint64_t a); uint64_t tor_ntohll(uint64_t a); @@ -117,8 +110,6 @@ int parse_http_time(const char *buf, struct tm *tm); int format_time_interval(char *out, size_t out_len, long interval);

/* File helpers */ -ssize_t write_all_to_fd(int fd, const char *buf, size_t count); -ssize_t read_all_from_fd(int fd, char *buf, size_t count);

#define write_all(fd, buf, count, isSock) \ ((isSock) ? write_all_to_socket((fd), (buf), (count)) \ @@ -139,76 +130,7 @@ const char *stream_status_to_string(enum stream_status stream_status);

enum stream_status get_string_from_pipe(int fd, char *buf, size_t count);

-MOCK_DECL(int,tor_unlink,(const char *pathname)); - -/** Return values from file_status(); see that function's documentation - * for details. */ -typedef enum { FN_ERROR, FN_NOENT, FN_FILE, FN_DIR, FN_EMPTY } file_status_t; -file_status_t file_status(const char *filename); - -/** Possible behaviors for check_private_dir() on encountering a nonexistent - * directory; see that function's documentation for details. */ -typedef unsigned int cpd_check_t; -#define CPD_NONE 0 -#define CPD_CREATE (1u << 0) -#define CPD_CHECK (1u << 1) -#define CPD_GROUP_OK (1u << 2) -#define CPD_GROUP_READ (1u << 3) -#define CPD_CHECK_MODE_ONLY (1u << 4) -#define CPD_RELAX_DIRMODE_CHECK (1u << 5) -MOCK_DECL(int, check_private_dir, - (const char *dirname, cpd_check_t check, - const char *effective_user)); - -#define OPEN_FLAGS_REPLACE (O_WRONLY|O_CREAT|O_TRUNC) -#define OPEN_FLAGS_APPEND (O_WRONLY|O_CREAT|O_APPEND) -#define OPEN_FLAGS_DONT_REPLACE (O_CREAT|O_EXCL|O_APPEND|O_WRONLY) -typedef struct open_file_t open_file_t; -int start_writing_to_file(const char *fname, int open_flags, int mode, - open_file_t **data_out); -FILE *start_writing_to_stdio_file(const char *fname, int open_flags, int mode, - open_file_t **data_out); -FILE *fdopen_file(open_file_t *file_data); -int finish_writing_to_file(open_file_t *file_data); -int abort_writing_to_file(open_file_t *file_data); -MOCK_DECL(int, -write_str_to_file,(const char *fname, const char *str, int bin)); -MOCK_DECL(int, -write_bytes_to_file,(const char *fname, const char *str, size_t len, - int bin)); -/** An ad-hoc type to hold a string of characters and a count; used by - * write_chunks_to_file. */ -typedef struct sized_chunk_t { - const char *bytes; - size_t len; -} sized_chunk_t; -struct smartlist_t; -int write_chunks_to_file(const char *fname, const struct smartlist_t *chunks, - int bin, int no_tempfile); -int append_bytes_to_file(const char *fname, const char *str, size_t len, - int bin); -int write_bytes_to_new_file(const char *fname, const char *str, size_t len, - int bin); - -/** Flag for read_file_to_str: open the file in binary mode. */ -#define RFTS_BIN 1 -/** Flag for read_file_to_str: it's okay if the file doesn't exist. */ -#define RFTS_IGNORE_MISSING 2 - -#ifndef _WIN32 -struct stat; -#endif -MOCK_DECL_ATTR(char *, read_file_to_str, - (const char *filename, int flags, struct stat *stat_out), - ATTR_MALLOC); -char *read_file_to_str_until_eof(int fd, size_t max_bytes_to_read, - size_t *sz_out) - ATTR_MALLOC; const char *unescape_string(const char *s, char **result, size_t *size_out); -char *get_unquoted_path(const char *path); -char *expand_filename(const char *filename); -MOCK_DECL(struct smartlist_t *, tor_listdir, (const char *dirname)); -int path_is_relative(const char *filename);

/* Process helpers */ void start_daemon(void); diff --git a/src/include.am b/src/include.am index 5d28ea34e..7818fb4f6 100644 --- a/src/include.am +++ b/src/include.am @@ -7,6 +7,7 @@ include src/lib/container/include.am include src/lib/crypt_ops/include.am include src/lib/defs/include.am include src/lib/fdio/include.am +include src/lib/fs/include.am include src/lib/include.libdonna.am include src/lib/intmath/include.am include src/lib/lock/include.am diff --git a/src/lib/fs/.may_include b/src/lib/fs/.may_include new file mode 100644 index 000000000..2321edbbe --- /dev/null +++ b/src/lib/fs/.may_include @@ -0,0 +1,11 @@ +orconfig.h +lib/cc/*.h +lib/container/*.h +lib/err/*.h +lib/fdio/*.h +lib/malloc/*.h +lib/fs/*.h +lib/sandbox/*.h +lib/string/*.h +lib/testsupport/testsupport.h +lib/log/*.h diff --git a/src/lib/fs/dir.c b/src/lib/fs/dir.c new file mode 100644 index 000000000..9f09327d8 --- /dev/null +++ b/src/lib/fs/dir.c @@ -0,0 +1,360 @@ +/* Copyright (c) 2003, Roger Dingledine + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2018, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +#include "lib/fs/dir.h" +#include "lib/fs/path.h" +#include "lib/fs/userdb.h" + +#include "lib/log/torlog.h" +#include "lib/log/util_bug.h" +#include "lib/log/win32err.h" +#include "lib/container/smartlist.h" +#include "lib/sandbox/sandbox.h" +#include "lib/malloc/util_malloc.h" +#include "lib/string/printf.h" +#include "lib/string/compat_string.h" + +#ifdef HAVE_SYS_TYPES_H +#include <sys/types.h> +#endif +#ifdef HAVE_SYS_STAT_H +#include <sys/stat.h> +#endif +#ifdef HAVE_UNISTD_H +#include <unistd.h> +#endif +#ifdef HAVE_FCNTL_H +#include <fcntl.h> +#endif + +#ifdef _WIN32 +#include <io.h> +#include <direct.h> +#include <windows.h> +#else /* !(defined(_WIN32)) */ +#include <dirent.h> +#include <pwd.h> +#include <grp.h> +#endif /* defined(_WIN32) */ + +#include <errno.h> +#include <string.h> + +/** Check whether <b>dirname</b> exists and is private. If yes return 0. + * If <b>dirname</b> does not exist: + * - if <b>check</b>&CPD_CREATE, try to create it and return 0 on success. + * - if <b>check</b>&CPD_CHECK, and we think we can create it, return 0. + * - if <b>check</b>&CPD_CHECK is false, and the directory exists, return 0. + * - otherwise, return -1. + * If CPD_GROUP_OK is set, then it's okay if the directory + * is group-readable, but in all cases we create the directory mode 0700. + * If CPD_GROUP_READ is set, existing directory behaves as CPD_GROUP_OK and + * if the directory is created it will use mode 0750 with group read + * permission. Group read privileges also assume execute permission + * as norm for directories. If CPD_CHECK_MODE_ONLY is set, then we don't + * alter the directory permissions if they are too permissive: + * we just return -1. + * When effective_user is not NULL, check permissions against the given user + * and its primary group. + */ +MOCK_IMPL(int, +check_private_dir,(const char *dirname, cpd_check_t check, + const char *effective_user)) +{ + int r; + struct stat st; + + tor_assert(dirname); + +#ifndef _WIN32 + int fd; + const struct passwd *pw = NULL; + uid_t running_uid; + gid_t running_gid; + + /* + * Goal is to harden the implementation by removing any + * potential for race between stat() and chmod(). + * chmod() accepts filename as argument. If an attacker can move + * the file between stat() and chmod(), a potential race exists. + * + * Several suggestions taken from: + * https://developer.apple.com/library/mac/documentation/ + * Security/Conceptual/SecureCodingGuide/Articles/RaceConditions.html + */ + + /* Open directory. + * O_NOFOLLOW to ensure that it does not follow symbolic links */ + fd = open(sandbox_intern_string(dirname), O_NOFOLLOW); + + /* Was there an error? Maybe the directory does not exist? */ + if (fd == -1) { + + if (errno != ENOENT) { + /* Other directory error */ + log_warn(LD_FS, "Directory %s cannot be read: %s", dirname, + strerror(errno)); + return -1; + } + + /* Received ENOENT: Directory does not exist */ + + /* Should we create the directory? */ + if (check & CPD_CREATE) { + log_info(LD_GENERAL, "Creating directory %s", dirname); + if (check & CPD_GROUP_READ) { + r = mkdir(dirname, 0750); + } else { + r = mkdir(dirname, 0700); + } + + /* check for mkdir() error */ + if (r) { + log_warn(LD_FS, "Error creating directory %s: %s", dirname, + strerror(errno)); + return -1; + } + + /* we just created the directory. try to open it again. + * permissions on the directory will be checked again below.*/ + fd = open(sandbox_intern_string(dirname), O_NOFOLLOW); + + if (fd == -1) { + log_warn(LD_FS, "Could not reopen recently created directory %s: %s", + dirname, + strerror(errno)); + return -1; + } else { + close(fd); + } + + } else if (!(check & CPD_CHECK)) { + log_warn(LD_FS, "Directory %s does not exist.", dirname); + return -1; + } + + /* XXXX In the case where check==CPD_CHECK, we should look at the + * parent directory a little harder. */ + return 0; + } + + tor_assert(fd >= 0); + + //f = tor_strdup(dirname); + //clean_name_for_stat(f); + log_debug(LD_FS, "stat()ing %s", dirname); + //r = stat(sandbox_intern_string(f), &st); + r = fstat(fd, &st); + if (r == -1) { + log_warn(LD_FS, "fstat() on directory %s failed.", dirname); + close(fd); + return -1; + } + //tor_free(f); + + /* check that dirname is a directory */ + if (!(st.st_mode & S_IFDIR)) { + log_warn(LD_FS, "%s is not a directory", dirname); + close(fd); + return -1; + } + + if (effective_user) { + /* Look up the user and group information. + * If we have a problem, bail out. */ + pw = tor_getpwnam(effective_user); + if (pw == NULL) { + log_warn(LD_CONFIG, "Error setting configured user: %s not found", + effective_user); + close(fd); + return -1; + } + running_uid = pw->pw_uid; + running_gid = pw->pw_gid; + } else { + running_uid = getuid(); + running_gid = getgid(); + } + if (st.st_uid != running_uid) { + char *process_ownername = NULL, *file_ownername = NULL; + + { + const struct passwd *pw_running = tor_getpwuid(running_uid); + process_ownername = pw_running ? tor_strdup(pw_running->pw_name) : + tor_strdup("<unknown>"); + } + + { + const struct passwd *pw_stat = tor_getpwuid(st.st_uid); + file_ownername = pw_stat ? tor_strdup(pw_stat->pw_name) : + tor_strdup("<unknown>"); + } + + log_warn(LD_FS, "%s is not owned by this user (%s, %d) but by " + "%s (%d). Perhaps you are running Tor as the wrong user?", + dirname, process_ownername, (int)running_uid, + file_ownername, (int)st.st_uid); + + tor_free(process_ownername); + tor_free(file_ownername); + close(fd); + return -1; + } + if ( (check & (CPD_GROUP_OK|CPD_GROUP_READ)) + && (st.st_gid != running_gid) && (st.st_gid != 0)) { + struct group *gr; + char *process_groupname = NULL; + gr = getgrgid(running_gid); + process_groupname = gr ? tor_strdup(gr->gr_name) : tor_strdup("<unknown>"); + gr = getgrgid(st.st_gid); + + log_warn(LD_FS, "%s is not owned by this group (%s, %d) but by group " + "%s (%d). Are you running Tor as the wrong user?", + dirname, process_groupname, (int)running_gid, + gr ? gr->gr_name : "<unknown>", (int)st.st_gid); + + tor_free(process_groupname); + close(fd); + return -1; + } + unsigned unwanted_bits = 0; + if (check & (CPD_GROUP_OK|CPD_GROUP_READ)) { + unwanted_bits = 0027; + } else { + unwanted_bits = 0077; + } + unsigned check_bits_filter = ~0; + if (check & CPD_RELAX_DIRMODE_CHECK) { + check_bits_filter = 0022; + } + if ((st.st_mode & unwanted_bits & check_bits_filter) != 0) { + unsigned new_mode; + if (check & CPD_CHECK_MODE_ONLY) { + log_warn(LD_FS, "Permissions on directory %s are too permissive.", + dirname); + close(fd); + return -1; + } + log_warn(LD_FS, "Fixing permissions on directory %s", dirname); + new_mode = st.st_mode; + new_mode |= 0700; /* Owner should have rwx */ + if (check & CPD_GROUP_READ) { + new_mode |= 0050; /* Group should have rx */ + } + new_mode &= ~unwanted_bits; /* Clear the bits that we didn't want set...*/ + if (fchmod(fd, new_mode)) { + log_warn(LD_FS, "Could not chmod directory %s: %s", dirname, + strerror(errno)); + close(fd); + return -1; + } else { + close(fd); + return 0; + } + } + close(fd); +#else /* !(!defined(_WIN32)) */ + /* Win32 case: we can't open() a directory. */ + (void)effective_user; + + char *f = tor_strdup(dirname); + clean_fname_for_stat(f); + log_debug(LD_FS, "stat()ing %s", f); + r = stat(sandbox_intern_string(f), &st); + tor_free(f); + if (r) { + if (errno != ENOENT) { + log_warn(LD_FS, "Directory %s cannot be read: %s", dirname, + strerror(errno)); + return -1; + } + if (check & CPD_CREATE) { + log_info(LD_GENERAL, "Creating directory %s", dirname); + r = mkdir(dirname); + if (r) { + log_warn(LD_FS, "Error creating directory %s: %s", dirname, + strerror(errno)); + return -1; + } + } else if (!(check & CPD_CHECK)) { + log_warn(LD_FS, "Directory %s does not exist.", dirname); + return -1; + } + return 0; + } + if (!(st.st_mode & S_IFDIR)) { + log_warn(LD_FS, "%s is not a directory", dirname); + return -1; + } + +#endif /* !defined(_WIN32) */ + return 0; +} + +/** Return a new list containing the filenames in the directory <b>dirname</b>. + * Return NULL on error or if <b>dirname</b> is not a directory. + */ +MOCK_IMPL(smartlist_t *, +tor_listdir, (const char *dirname)) +{ + smartlist_t *result; +#ifdef _WIN32 + char *pattern=NULL; + TCHAR tpattern[MAX_PATH] = {0}; + char name[MAX_PATH*2+1] = {0}; + HANDLE handle; + WIN32_FIND_DATA findData; + tor_asprintf(&pattern, "%s\*", dirname); +#ifdef UNICODE + mbstowcs(tpattern,pattern,MAX_PATH); +#else + strlcpy(tpattern, pattern, MAX_PATH); +#endif + if (INVALID_HANDLE_VALUE == (handle = FindFirstFile(tpattern, &findData))) { + tor_free(pattern); + return NULL; + } + result = smartlist_new(); + while (1) { +#ifdef UNICODE + wcstombs(name,findData.cFileName,MAX_PATH); + name[sizeof(name)-1] = '\0'; +#else + strlcpy(name,findData.cFileName,sizeof(name)); +#endif /* defined(UNICODE) */ + if (strcmp(name, ".") && + strcmp(name, "..")) { + smartlist_add_strdup(result, name); + } + if (!FindNextFile(handle, &findData)) { + DWORD err; + if ((err = GetLastError()) != ERROR_NO_MORE_FILES) { + char *errstr = format_win32_error(err); + log_warn(LD_FS, "Error reading directory '%s': %s", dirname, errstr); + tor_free(errstr); + } + break; + } + } + FindClose(handle); + tor_free(pattern); +#else /* !(defined(_WIN32)) */ + const char *prot_dname = sandbox_intern_string(dirname); + DIR *d; + struct dirent *de; + if (!(d = opendir(prot_dname))) + return NULL; + + result = smartlist_new(); + while ((de = readdir(d))) { + if (!strcmp(de->d_name, ".") || + !strcmp(de->d_name, "..")) + continue; + smartlist_add_strdup(result, de->d_name); + } + closedir(d); +#endif /* defined(_WIN32) */ + return result; +} diff --git a/src/lib/fs/dir.h b/src/lib/fs/dir.h new file mode 100644 index 000000000..925211fbd --- /dev/null +++ b/src/lib/fs/dir.h @@ -0,0 +1,27 @@ +/* Copyright (c) 2003-2004, Roger Dingledine + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2018, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +#ifndef TOR_DIR_H +#define TOR_DIR_H + +#include "lib/cc/compat_compiler.h" +#include "lib/testsupport/testsupport.h" + +/** Possible behaviors for check_private_dir() on encountering a nonexistent + * directory; see that function's documentation for details. */ +typedef unsigned int cpd_check_t; +#define CPD_NONE 0 +#define CPD_CREATE (1u << 0) +#define CPD_CHECK (1u << 1) +#define CPD_GROUP_OK (1u << 2) +#define CPD_GROUP_READ (1u << 3) +#define CPD_CHECK_MODE_ONLY (1u << 4) +#define CPD_RELAX_DIRMODE_CHECK (1u << 5) +MOCK_DECL(int, check_private_dir, (const char *dirname, cpd_check_t check, + const char *effective_user)); + +MOCK_DECL(struct smartlist_t *, tor_listdir, (const char *dirname)); + +#endif diff --git a/src/lib/fs/files.c b/src/lib/fs/files.c new file mode 100644 index 000000000..0335f6dc5 --- /dev/null +++ b/src/lib/fs/files.c @@ -0,0 +1,711 @@ +/* Copyright (c) 2003-2004, Roger Dingledine + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2018, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +#ifdef _WIN32 +#include <windows.h> +#endif + +#include "lib/fs/files.h" +#include "lib/fs/path.h" +#include "lib/container/smartlist.h" +#include "lib/log/torlog.h" +#include "lib/log/util_bug.h" +#include "lib/log/escape.h" +#include "lib/err/torerr.h" +#include "lib/malloc/util_malloc.h" +#include "lib/sandbox/sandbox.h" +#include "lib/string/printf.h" +#include "lib/string/util_string.h" +#include "lib/fdio/fdio.h" + +#ifdef HAVE_SYS_TYPES_H +#include <sys/types.h> +#endif +#ifdef HAVE_SYS_STAT_H +#include <sys/stat.h> +#endif +#ifdef HAVE_UTIME_H +#include <utime.h> +#endif +#ifdef HAVE_SYS_TIME_H +#include <sys/time.h> +#endif +#ifdef HAVE_FCNTL_H +#include <fcntl.h> +#endif +#ifdef HAVE_UNISTD_H +#include <unistd.h> +#endif +#include <errno.h> +#include <stdio.h> +#include <string.h> + +/** As open(path, flags, mode), but return an fd with the close-on-exec mode + * set. */ +int +tor_open_cloexec(const char *path, int flags, unsigned mode) +{ + int fd; + const char *p = sandbox_intern_string(path); +#ifdef O_CLOEXEC + fd = open(p, flags|O_CLOEXEC, mode); + if (fd >= 0) + return fd; + /* If we got an error, see if it is EINVAL. EINVAL might indicate that, + * even though we were built on a system with O_CLOEXEC support, we + * are running on one without. */ + if (errno != EINVAL) + return -1; +#endif /* defined(O_CLOEXEC) */ + + log_debug(LD_FS, "Opening %s with flags %x", p, flags); + fd = open(p, flags, mode); +#ifdef FD_CLOEXEC + if (fd >= 0) { + if (fcntl(fd, F_SETFD, FD_CLOEXEC) == -1) { + log_warn(LD_FS,"Couldn't set FD_CLOEXEC: %s", strerror(errno)); + close(fd); + return -1; + } + } +#endif /* defined(FD_CLOEXEC) */ + return fd; +} + +/** As fopen(path,mode), but ensures that the O_CLOEXEC bit is set on the + * underlying file handle. */ +FILE * +tor_fopen_cloexec(const char *path, const char *mode) +{ + FILE *result = fopen(path, mode); +#ifdef FD_CLOEXEC + if (result != NULL) { + if (fcntl(fileno(result), F_SETFD, FD_CLOEXEC) == -1) { + log_warn(LD_FS,"Couldn't set FD_CLOEXEC: %s", strerror(errno)); + fclose(result); + return NULL; + } + } +#endif /* defined(FD_CLOEXEC) */ + return result; +} + +/** As rename(), but work correctly with the sandbox. */ +int +tor_rename(const char *path_old, const char *path_new) +{ + log_debug(LD_FS, "Renaming %s to %s", path_old, path_new); + return rename(sandbox_intern_string(path_old), + sandbox_intern_string(path_new)); +} + +/** + * Rename the file <b>from</b> to the file <b>to</b>. On Unix, this is + * the same as rename(2). On windows, this removes <b>to</b> first if + * it already exists. + * Returns 0 on success. Returns -1 and sets errno on failure. + */ +int +replace_file(const char *from, const char *to) +{ +#ifndef _WIN32 + return tor_rename(from, to); +#else + switch (file_status(to)) + { + case FN_NOENT: + break; + case FN_FILE: + case FN_EMPTY: + if (unlink(to)) return -1; + break; + case FN_ERROR: + return -1; + case FN_DIR: + errno = EISDIR; + return -1; + } + return tor_rename(from,to); +#endif /* !defined(_WIN32) */ +} + +/** Change <b>fname</b>'s modification time to now. */ +int +touch_file(const char *fname) +{ + if (utime(fname, NULL)!=0) + return -1; + return 0; +} + +/** Wrapper for unlink() to make it mockable for the test suite; returns 0 + * if unlinking the file succeeded, -1 and sets errno if unlinking fails. + */ + +MOCK_IMPL(int, +tor_unlink,(const char *pathname)) +{ + return unlink(pathname); +} + +/** Write <b>count</b> bytes from <b>buf</b> to <b>fd</b>. Return the number + * of bytes written, or -1 on error. Only use if fd is a blocking fd. */ +ssize_t +write_all_to_fd(int fd, const char *buf, size_t count) +{ + size_t written = 0; + ssize_t result; + raw_assert(count < SSIZE_MAX); + + while (written != count) { + result = write(fd, buf+written, count-written); + if (result<0) + return -1; + written += result; + } + return (ssize_t)count; +} + +/** Read from <b>fd</b> to <b>buf</b>, until we get <b>count</b> bytes or + * reach the end of the file. Return the number of bytes read, or -1 on + * error. Only use if fd is a blocking fd. */ +ssize_t +read_all_from_fd(int fd, char *buf, size_t count) +{ + size_t numread = 0; + ssize_t result; + + if (count > SIZE_T_CEILING || count > SSIZE_MAX) { + errno = EINVAL; + return -1; + } + + while (numread < count) { + result = read(fd, buf+numread, count-numread); + if (result<0) + return -1; + else if (result == 0) + break; + numread += result; + } + return (ssize_t)numread; +} + +/** Return: + * FN_ERROR if filename can't be read, is NULL, or is zero-length, + * FN_NOENT if it doesn't exist, + * FN_FILE if it is a non-empty regular file, or a FIFO on unix-like systems, + * FN_EMPTY for zero-byte regular files, + * FN_DIR if it's a directory, and + * FN_ERROR for any other file type. + * On FN_ERROR and FN_NOENT, sets errno. (errno is not set when FN_ERROR + * is returned due to an unhandled file type.) */ +file_status_t +file_status(const char *fname) +{ + struct stat st; + char *f; + int r; + if (!fname || strlen(fname) == 0) { + return FN_ERROR; + } + f = tor_strdup(fname); + clean_fname_for_stat(f); + log_debug(LD_FS, "stat()ing %s", f); + r = stat(sandbox_intern_string(f), &st); + tor_free(f); + if (r) { + if (errno == ENOENT) { + return FN_NOENT; + } + return FN_ERROR; + } + if (st.st_mode & S_IFDIR) { + return FN_DIR; + } else if (st.st_mode & S_IFREG) { + if (st.st_size > 0) { + return FN_FILE; + } else if (st.st_size == 0) { + return FN_EMPTY; + } else { + return FN_ERROR; + } +#ifndef _WIN32 + } else if (st.st_mode & S_IFIFO) { + return FN_FILE; +#endif + } else { + return FN_ERROR; + } +} + +/** Create a file named <b>fname</b> with the contents <b>str</b>. Overwrite + * the previous <b>fname</b> if possible. Return 0 on success, -1 on failure. + * + * This function replaces the old file atomically, if possible. This + * function, and all other functions in util.c that create files, create them + * with mode 0600. + */ +MOCK_IMPL(int, +write_str_to_file,(const char *fname, const char *str, int bin)) +{ +#ifdef _WIN32 + if (!bin && strchr(str, '\r')) { + log_warn(LD_BUG, + "We're writing a text string that already contains a CR to %s", + escaped(fname)); + } +#endif /* defined(_WIN32) */ + return write_bytes_to_file(fname, str, strlen(str), bin); +} + +/** Represents a file that we're writing to, with support for atomic commit: + * we can write into a temporary file, and either remove the file on + * failure, or replace the original file on success. */ +struct open_file_t { + char *tempname; /**< Name of the temporary file. */ + char *filename; /**< Name of the original file. */ + unsigned rename_on_close:1; /**< Are we using the temporary file or not? */ + unsigned binary:1; /**< Did we open in binary mode? */ + int fd; /**< fd for the open file. */ + FILE *stdio_file; /**< stdio wrapper for <b>fd</b>. */ +}; + +/** Try to start writing to the file in <b>fname</b>, passing the flags + * <b>open_flags</b> to the open() syscall, creating the file (if needed) with + * access value <b>mode</b>. If the O_APPEND flag is set, we append to the + * original file. Otherwise, we open a new temporary file in the same + * directory, and either replace the original or remove the temporary file + * when we're done. + * + * Return the fd for the newly opened file, and store working data in + * *<b>data_out</b>. The caller should not close the fd manually: + * instead, call finish_writing_to_file() or abort_writing_to_file(). + * Returns -1 on failure. + * + * NOTE: When not appending, the flags O_CREAT and O_TRUNC are treated + * as true and the flag O_EXCL is treated as false. + * + * NOTE: Ordinarily, O_APPEND means "seek to the end of the file before each + * write()". We don't do that. + */ +int +start_writing_to_file(const char *fname, int open_flags, int mode, + open_file_t **data_out) +{ + open_file_t *new_file = tor_malloc_zero(sizeof(open_file_t)); + const char *open_name; + int append = 0; + + tor_assert(fname); + tor_assert(data_out); +#if (O_BINARY != 0 && O_TEXT != 0) + tor_assert((open_flags & (O_BINARY|O_TEXT)) != 0); +#endif + new_file->fd = -1; + new_file->filename = tor_strdup(fname); + if (open_flags & O_APPEND) { + open_name = fname; + new_file->rename_on_close = 0; + append = 1; + open_flags &= ~O_APPEND; + } else { + tor_asprintf(&new_file->tempname, "%s.tmp", fname); + open_name = new_file->tempname; + /* We always replace an existing temporary file if there is one. */ + open_flags |= O_CREAT|O_TRUNC; + open_flags &= ~O_EXCL; + new_file->rename_on_close = 1; + } +#if O_BINARY != 0 + if (open_flags & O_BINARY) + new_file->binary = 1; +#endif + + new_file->fd = tor_open_cloexec(open_name, open_flags, mode); + if (new_file->fd < 0) { + log_warn(LD_FS, "Couldn't open "%s" (%s) for writing: %s", + open_name, fname, strerror(errno)); + goto err; + } + if (append) { + if (tor_fd_seekend(new_file->fd) < 0) { + log_warn(LD_FS, "Couldn't seek to end of file "%s": %s", open_name, + strerror(errno)); + goto err; + } + } + + *data_out = new_file; + + return new_file->fd; + + err: + if (new_file->fd >= 0) + close(new_file->fd); + *data_out = NULL; + tor_free(new_file->filename); + tor_free(new_file->tempname); + tor_free(new_file); + return -1; +} + +/** Given <b>file_data</b> from start_writing_to_file(), return a stdio FILE* + * that can be used to write to the same file. The caller should not mix + * stdio calls with non-stdio calls. */ +FILE * +fdopen_file(open_file_t *file_data) +{ + tor_assert(file_data); + if (file_data->stdio_file) + return file_data->stdio_file; + tor_assert(file_data->fd >= 0); + if (!(file_data->stdio_file = fdopen(file_data->fd, + file_data->binary?"ab":"a"))) { + log_warn(LD_FS, "Couldn't fdopen "%s" [%d]: %s", file_data->filename, + file_data->fd, strerror(errno)); + } + return file_data->stdio_file; +} + +/** Combines start_writing_to_file with fdopen_file(): arguments are as + * for start_writing_to_file, but */ +FILE * +start_writing_to_stdio_file(const char *fname, int open_flags, int mode, + open_file_t **data_out) +{ + FILE *res; + if (start_writing_to_file(fname, open_flags, mode, data_out)<0) + return NULL; + if (!(res = fdopen_file(*data_out))) { + abort_writing_to_file(*data_out); + *data_out = NULL; + } + return res; +} + +/** Helper function: close and free the underlying file and memory in + * <b>file_data</b>. If we were writing into a temporary file, then delete + * that file (if abort_write is true) or replaces the target file with + * the temporary file (if abort_write is false). */ +static int +finish_writing_to_file_impl(open_file_t *file_data, int abort_write) +{ + int r = 0; + + tor_assert(file_data && file_data->filename); + if (file_data->stdio_file) { + if (fclose(file_data->stdio_file)) { + log_warn(LD_FS, "Error closing "%s": %s", file_data->filename, + strerror(errno)); + abort_write = r = -1; + } + } else if (file_data->fd >= 0 && close(file_data->fd) < 0) { + log_warn(LD_FS, "Error flushing "%s": %s", file_data->filename, + strerror(errno)); + abort_write = r = -1; + } + + if (file_data->rename_on_close) { + tor_assert(file_data->tempname && file_data->filename); + if (!abort_write) { + tor_assert(strcmp(file_data->filename, file_data->tempname)); + if (replace_file(file_data->tempname, file_data->filename)) { + log_warn(LD_FS, "Error replacing "%s": %s", file_data->filename, + strerror(errno)); + abort_write = r = -1; + } + } + if (abort_write) { + int res = unlink(file_data->tempname); + if (res != 0) { + /* We couldn't unlink and we'll leave a mess behind */ + log_warn(LD_FS, "Failed to unlink %s: %s", + file_data->tempname, strerror(errno)); + r = -1; + } + } + } + + tor_free(file_data->filename); + tor_free(file_data->tempname); + tor_free(file_data); + + return r; +} + +/** Finish writing to <b>file_data</b>: close the file handle, free memory as + * needed, and if using a temporary file, replace the original file with + * the temporary file. */ +int +finish_writing_to_file(open_file_t *file_data) +{ + return finish_writing_to_file_impl(file_data, 0); +} + +/** Finish writing to <b>file_data</b>: close the file handle, free memory as + * needed, and if using a temporary file, delete it. */ +int +abort_writing_to_file(open_file_t *file_data) +{ + return finish_writing_to_file_impl(file_data, 1); +} + +/** Helper: given a set of flags as passed to open(2), open the file + * <b>fname</b> and write all the sized_chunk_t structs in <b>chunks</b> to + * the file. Do so as atomically as possible e.g. by opening temp files and + * renaming. */ +static int +write_chunks_to_file_impl(const char *fname, const smartlist_t *chunks, + int open_flags) +{ + open_file_t *file = NULL; + int fd; + ssize_t result; + fd = start_writing_to_file(fname, open_flags, 0600, &file); + if (fd<0) + return -1; + SMARTLIST_FOREACH(chunks, sized_chunk_t *, chunk, + { + result = write_all_to_fd(fd, chunk->bytes, chunk->len); + if (result < 0) { + log_warn(LD_FS, "Error writing to "%s": %s", fname, + strerror(errno)); + goto err; + } + tor_assert((size_t)result == chunk->len); + }); + + return finish_writing_to_file(file); + err: + abort_writing_to_file(file); + return -1; +} + +/** Given a smartlist of sized_chunk_t, write them to a file + * <b>fname</b>, overwriting or creating the file as necessary. + * If <b>no_tempfile</b> is 0 then the file will be written + * atomically. */ +int +write_chunks_to_file(const char *fname, const smartlist_t *chunks, int bin, + int no_tempfile) +{ + int flags = OPEN_FLAGS_REPLACE|(bin?O_BINARY:O_TEXT); + + if (no_tempfile) { + /* O_APPEND stops write_chunks_to_file from using tempfiles */ + flags |= O_APPEND; + } + return write_chunks_to_file_impl(fname, chunks, flags); +} + +/** Write <b>len</b> bytes, starting at <b>str</b>, to <b>fname</b> + using the open() flags passed in <b>flags</b>. */ +static int +write_bytes_to_file_impl(const char *fname, const char *str, size_t len, + int flags) +{ + int r; + sized_chunk_t c = { str, len }; + smartlist_t *chunks = smartlist_new(); + smartlist_add(chunks, &c); + r = write_chunks_to_file_impl(fname, chunks, flags); + smartlist_free(chunks); + return r; +} + +/** As write_str_to_file, but does not assume a NUL-terminated + * string. Instead, we write <b>len</b> bytes, starting at <b>str</b>. */ +MOCK_IMPL(int, +write_bytes_to_file,(const char *fname, const char *str, size_t len, + int bin)) +{ + return write_bytes_to_file_impl(fname, str, len, + OPEN_FLAGS_REPLACE|(bin?O_BINARY:O_TEXT)); +} + +/** As write_bytes_to_file, but if the file already exists, append the bytes + * to the end of the file instead of overwriting it. */ +int +append_bytes_to_file(const char *fname, const char *str, size_t len, + int bin) +{ + return write_bytes_to_file_impl(fname, str, len, + OPEN_FLAGS_APPEND|(bin?O_BINARY:O_TEXT)); +} + +/** Like write_str_to_file(), but also return -1 if there was a file + already residing in <b>fname</b>. */ +int +write_bytes_to_new_file(const char *fname, const char *str, size_t len, + int bin) +{ + return write_bytes_to_file_impl(fname, str, len, + OPEN_FLAGS_DONT_REPLACE| + (bin?O_BINARY:O_TEXT)); +} + +/** + * Read the contents of the open file <b>fd</b> presuming it is a FIFO + * (or similar) file descriptor for which the size of the file isn't + * known ahead of time. Return NULL on failure, and a NUL-terminated + * string on success. On success, set <b>sz_out</b> to the number of + * bytes read. + */ +char * +read_file_to_str_until_eof(int fd, size_t max_bytes_to_read, size_t *sz_out) +{ + ssize_t r; + size_t pos = 0; + char *string = NULL; + size_t string_max = 0; + + if (max_bytes_to_read+1 >= SIZE_T_CEILING) { + errno = EINVAL; + return NULL; + } + + do { + /* XXXX This "add 1K" approach is a little goofy; if we care about + * performance here, we should be doubling. But in practice we shouldn't + * be using this function on big files anyway. */ + string_max = pos + 1024; + if (string_max > max_bytes_to_read) + string_max = max_bytes_to_read + 1; + string = tor_realloc(string, string_max); + r = read(fd, string + pos, string_max - pos - 1); + if (r < 0) { + int save_errno = errno; + tor_free(string); + errno = save_errno; + return NULL; + } + + pos += r; + } while (r > 0 && pos < max_bytes_to_read); + + tor_assert(pos < string_max); + *sz_out = pos; + string[pos] = '\0'; + return string; +} + +/** Read the contents of <b>filename</b> into a newly allocated + * string; return the string on success or NULL on failure. + * + * If <b>stat_out</b> is provided, store the result of stat()ing the + * file into <b>stat_out</b>. + * + * If <b>flags</b> &amp; RFTS_BIN, open the file in binary mode. + * If <b>flags</b> &amp; RFTS_IGNORE_MISSING, don't warn if the file + * doesn't exist. + */ +/* + * This function <em>may</em> return an erroneous result if the file + * is modified while it is running, but must not crash or overflow. + * Right now, the error case occurs when the file length grows between + * the call to stat and the call to read_all: the resulting string will + * be truncated. + */ +MOCK_IMPL(char *, +read_file_to_str, (const char *filename, int flags, struct stat *stat_out)) +{ + int fd; /* router file */ + struct stat statbuf; + char *string; + ssize_t r; + int bin = flags & RFTS_BIN; + + tor_assert(filename); + + fd = tor_open_cloexec(filename,O_RDONLY|(bin?O_BINARY:O_TEXT),0); + if (fd<0) { + int severity = LOG_WARN; + int save_errno = errno; + if (errno == ENOENT && (flags & RFTS_IGNORE_MISSING)) + severity = LOG_INFO; + log_fn(severity, LD_FS,"Could not open "%s": %s",filename, + strerror(errno)); + errno = save_errno; + return NULL; + } + + if (fstat(fd, &statbuf)<0) { + int save_errno = errno; + close(fd); + log_warn(LD_FS,"Could not fstat "%s".",filename); + errno = save_errno; + return NULL; + } + +#ifndef _WIN32 +/** When we detect that we're reading from a FIFO, don't read more than + * this many bytes. It's insane overkill for most uses. */ +#define FIFO_READ_MAX (1024*1024) + if (S_ISFIFO(statbuf.st_mode)) { + size_t sz = 0; + string = read_file_to_str_until_eof(fd, FIFO_READ_MAX, &sz); + int save_errno = errno; + if (string && stat_out) { + statbuf.st_size = sz; + memcpy(stat_out, &statbuf, sizeof(struct stat)); + } + close(fd); + if (!string) + errno = save_errno; + return string; + } +#endif /* !defined(_WIN32) */ + + if ((uint64_t)(statbuf.st_size)+1 >= SIZE_T_CEILING) { + close(fd); + errno = EINVAL; + return NULL; + } + + string = tor_malloc((size_t)(statbuf.st_size+1)); + + r = read_all_from_fd(fd,string,(size_t)statbuf.st_size); + if (r<0) { + int save_errno = errno; + log_warn(LD_FS,"Error reading from file "%s": %s", filename, + strerror(errno)); + tor_free(string); + close(fd); + errno = save_errno; + return NULL; + } + string[r] = '\0'; /* NUL-terminate the result. */ + +#if defined(_WIN32) || defined(__CYGWIN__) + if (!bin && strchr(string, '\r')) { + log_debug(LD_FS, "We didn't convert CRLF to LF as well as we hoped " + "when reading %s. Coping.", + filename); + tor_strstrip(string, "\r"); + r = strlen(string); + } + if (!bin) { + statbuf.st_size = (size_t) r; + } else +#endif /* defined(_WIN32) || defined(__CYGWIN__) */ + if (r != statbuf.st_size) { + /* Unless we're using text mode on win32, we'd better have an exact + * match for size. */ + int save_errno = errno; + log_warn(LD_FS,"Could read only %d of %ld bytes of file "%s".", + (int)r, (long)statbuf.st_size,filename); + tor_free(string); + close(fd); + errno = save_errno; + return NULL; + } + close(fd); + if (stat_out) { + memcpy(stat_out, &statbuf, sizeof(struct stat)); + } + + return string; +} diff --git a/src/lib/fs/files.h b/src/lib/fs/files.h new file mode 100644 index 000000000..be4ec485f --- /dev/null +++ b/src/lib/fs/files.h @@ -0,0 +1,100 @@ +/* Copyright (c) 2003-2004, Roger Dingledine + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2018, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +#ifndef TOR_FS_H +#define TOR_FS_H + +#include "lib/cc/compat_compiler.h" +#include "lib/cc/torint.h" +#include "lib/testsupport/testsupport.h" + +#include <stddef.h> +#include <stdio.h> + +#ifdef _WIN32 +/* We need these for struct stat to work */ +#ifdef HAVE_SYS_TYPES_H +#include <sys/types.h> +#endif +#ifdef HAVE_SYS_STAT_H +#include <sys/stat.h> +#endif +#endif + +#ifndef O_BINARY +#define O_BINARY 0 +#endif +#ifndef O_TEXT +#define O_TEXT 0 +#endif +#ifndef O_NOFOLLOW +#define O_NOFOLLOW 0 +#endif + +struct stat; + +int tor_open_cloexec(const char *path, int flags, unsigned mode); +FILE *tor_fopen_cloexec(const char *path, const char *mode); +int tor_rename(const char *path_old, const char *path_new); + +int replace_file(const char *from, const char *to); +int touch_file(const char *fname); + +MOCK_DECL(int,tor_unlink,(const char *pathname)); + +/** Return values from file_status(); see that function's documentation + * for details. */ +typedef enum { FN_ERROR, FN_NOENT, FN_FILE, FN_DIR, FN_EMPTY } file_status_t; + +file_status_t file_status(const char *filename); + +int64_t tor_get_avail_disk_space(const char *path); + +ssize_t write_all_to_fd(int fd, const char *buf, size_t count); +ssize_t read_all_from_fd(int fd, char *buf, size_t count); + +#define OPEN_FLAGS_REPLACE (O_WRONLY|O_CREAT|O_TRUNC) +#define OPEN_FLAGS_APPEND (O_WRONLY|O_CREAT|O_APPEND) +#define OPEN_FLAGS_DONT_REPLACE (O_CREAT|O_EXCL|O_APPEND|O_WRONLY) +typedef struct open_file_t open_file_t; +int start_writing_to_file(const char *fname, int open_flags, int mode, + open_file_t **data_out); +FILE *start_writing_to_stdio_file(const char *fname, int open_flags, int mode, + open_file_t **data_out); +FILE *fdopen_file(open_file_t *file_data); +int finish_writing_to_file(open_file_t *file_data); +int abort_writing_to_file(open_file_t *file_data); +MOCK_DECL(int, write_str_to_file,(const char *fname, const char *str, + int bin)); +MOCK_DECL(int, write_bytes_to_file,(const char *fname, const char *str, + size_t len,int bin)); + +/** An ad-hoc type to hold a string of characters and a count; used by + * write_chunks_to_file. */ +typedef struct sized_chunk_t { + const char *bytes; + size_t len; +} sized_chunk_t; +struct smartlist_t; +int write_chunks_to_file(const char *fname, const struct smartlist_t *chunks, + int bin, int no_tempfile); +int append_bytes_to_file(const char *fname, const char *str, size_t len, + int bin); +int write_bytes_to_new_file(const char *fname, const char *str, size_t len, + int bin); + +/** Flag for read_file_to_str: open the file in binary mode. */ +#define RFTS_BIN 1 +/** Flag for read_file_to_str: it's okay if the file doesn't exist. */ +#define RFTS_IGNORE_MISSING 2 + +MOCK_DECL_ATTR(char *, read_file_to_str,(const char *filename, int flags, + struct stat *stat_out), + ATTR_MALLOC); +char *read_file_to_str_until_eof(int fd, size_t max_bytes_to_read, + size_t *sz_out) + ATTR_MALLOC; + +#endif diff --git a/src/lib/fs/include.am b/src/lib/fs/include.am new file mode 100644 index 000000000..35dba6068 --- /dev/null +++ b/src/lib/fs/include.am @@ -0,0 +1,25 @@ + +noinst_LIBRARIES += src/lib/libtor-fs.a + +if UNITTESTS_ENABLED +noinst_LIBRARIES += src/lib/libtor-fs-testing.a +endif + +src_lib_libtor_fs_a_SOURCES = \ + src/lib/fs/dir.c \ + src/lib/fs/files.c \ + src/lib/fs/mmap.c \ + src/lib/fs/path.c \ + src/lib/fs/userdb.c + +src_lib_libtor_fs_testing_a_SOURCES = \ + $(src_lib_libtor_fs_a_SOURCES) +src_lib_libtor_fs_testing_a_CPPFLAGS = $(AM_CPPFLAGS) $(TEST_CPPFLAGS) +src_lib_libtor_fs_testing_a_CFLAGS = $(AM_CFLAGS) $(TEST_CFLAGS) + +noinst_HEADERS += \ + src/lib/fs/dir.h \ + src/lib/fs/files.h \ + src/lib/fs/mmap.h \ + src/lib/fs/path.h \ + src/lib/fs/userdb.h diff --git a/src/lib/fs/mmap.c b/src/lib/fs/mmap.c new file mode 100644 index 000000000..6d69fd5e7 --- /dev/null +++ b/src/lib/fs/mmap.c @@ -0,0 +1,234 @@ +/* Copyright (c) 2003-2004, Roger Dingledine + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2018, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +#include "lib/fs/mmap.h" +#include "lib/fs/files.h" +#include "lib/log/torlog.h" +#include "lib/log/util_bug.h" +#include "lib/log/win32err.h" +#include "lib/string/compat_string.h" +#include "lib/malloc/util_malloc.h" + +#ifdef HAVE_MMAP +#include <sys/mman.h> +#endif +#ifdef HAVE_SYS_STAT_H +#include <sys/stat.h> +#endif +#ifdef HAVE_UNISTD_H +#include <unistd.h> +#endif +#ifdef HAVE_FCNTL_H +#include <fcntl.h> +#endif + +#ifdef _WIN32 +#include <windows.h> +#endif + +#include <errno.h> +#include <string.h> + +#if defined(HAVE_MMAP) || defined(RUNNING_DOXYGEN) +/** Try to create a memory mapping for <b>filename</b> and return it. On + * failure, return NULL. Sets errno properly, using ERANGE to mean + * "empty file". Must only be called on trusted Tor-owned files, as changing + * the underlying file's size causes unspecified behavior. */ +tor_mmap_t * +tor_mmap_file(const char *filename) +{ + int fd; /* router file */ + char *string; + int result; + tor_mmap_t *res; + size_t size, filesize; + struct stat st; + + tor_assert(filename); + + fd = tor_open_cloexec(filename, O_RDONLY, 0); + if (fd<0) { + int save_errno = errno; + int severity = (errno == ENOENT) ? LOG_INFO : LOG_WARN; + log_fn(severity, LD_FS,"Could not open "%s" for mmap(): %s",filename, + strerror(errno)); + errno = save_errno; + return NULL; + } + + /* Get the size of the file */ + result = fstat(fd, &st); + if (result != 0) { + int save_errno = errno; + log_warn(LD_FS, + "Couldn't fstat opened descriptor for "%s" during mmap: %s", + filename, strerror(errno)); + close(fd); + errno = save_errno; + return NULL; + } + size = filesize = (size_t)(st.st_size); + + if (st.st_size > SSIZE_T_CEILING || (off_t)size < st.st_size) { + log_warn(LD_FS, "File "%s" is too large. Ignoring.",filename); + errno = EFBIG; + close(fd); + return NULL; + } + if (!size) { + /* Zero-length file. If we call mmap on it, it will succeed but + * return NULL, and bad things will happen. So just fail. */ + log_info(LD_FS,"File "%s" is empty. Ignoring.",filename); + errno = ERANGE; + close(fd); + return NULL; + } + + string = mmap(0, size, PROT_READ, MAP_PRIVATE, fd, 0); + close(fd); + if (string == MAP_FAILED) { + int save_errno = errno; + log_warn(LD_FS,"Could not mmap file "%s": %s", filename, + strerror(errno)); + errno = save_errno; + return NULL; + } + + res = tor_malloc_zero(sizeof(tor_mmap_t)); + res->data = string; + res->size = filesize; + res->mapping_size = size; + + return res; +} +/** Release storage held for a memory mapping; returns 0 on success, + * or -1 on failure (and logs a warning). */ +int +tor_munmap_file(tor_mmap_t *handle) +{ + int res; + + if (handle == NULL) + return 0; + + res = munmap((char*)handle->data, handle->mapping_size); + if (res == 0) { + /* munmap() succeeded */ + tor_free(handle); + } else { + log_warn(LD_FS, "Failed to munmap() in tor_munmap_file(): %s", + strerror(errno)); + res = -1; + } + + return res; +} +#elif defined(_WIN32) +tor_mmap_t * +tor_mmap_file(const char *filename) +{ + TCHAR tfilename[MAX_PATH]= {0}; + tor_mmap_t *res = tor_malloc_zero(sizeof(tor_mmap_t)); + int empty = 0; + HANDLE file_handle = INVALID_HANDLE_VALUE; + DWORD size_low, size_high; + uint64_t real_size; + res->mmap_handle = NULL; +#ifdef UNICODE + mbstowcs(tfilename,filename,MAX_PATH); +#else + strlcpy(tfilename,filename,MAX_PATH); +#endif + file_handle = CreateFile(tfilename, + GENERIC_READ, FILE_SHARE_READ, + NULL, + OPEN_EXISTING, + FILE_ATTRIBUTE_NORMAL, + 0); + + if (file_handle == INVALID_HANDLE_VALUE) + goto win_err; + + size_low = GetFileSize(file_handle, &size_high); + + if (size_low == INVALID_FILE_SIZE && GetLastError() != NO_ERROR) { + log_warn(LD_FS,"Error getting size of "%s".",filename); + goto win_err; + } + if (size_low == 0 && size_high == 0) { + log_info(LD_FS,"File "%s" is empty. Ignoring.",filename); + empty = 1; + goto err; + } + real_size = (((uint64_t)size_high)<<32) | size_low; + if (real_size > SIZE_MAX) { + log_warn(LD_FS,"File "%s" is too big to map; not trying.",filename); + goto err; + } + res->size = real_size; + + res->mmap_handle = CreateFileMapping(file_handle, + NULL, + PAGE_READONLY, + size_high, + size_low, + NULL); + if (res->mmap_handle == NULL) + goto win_err; + res->data = (char*) MapViewOfFile(res->mmap_handle, + FILE_MAP_READ, + 0, 0, 0); + if (!res->data) + goto win_err; + + CloseHandle(file_handle); + return res; + win_err: { + DWORD e = GetLastError(); + int severity = (e == ERROR_FILE_NOT_FOUND || e == ERROR_PATH_NOT_FOUND) ? + LOG_INFO : LOG_WARN; + char *msg = format_win32_error(e); + log_fn(severity, LD_FS, "Couldn't mmap file "%s": %s", filename, msg); + tor_free(msg); + if (e == ERROR_FILE_NOT_FOUND || e == ERROR_PATH_NOT_FOUND) + errno = ENOENT; + else + errno = EINVAL; + } + err: + if (empty) + errno = ERANGE; + if (file_handle != INVALID_HANDLE_VALUE) + CloseHandle(file_handle); + tor_munmap_file(res); + return NULL; +} + +/* Unmap the file, and return 0 for success or -1 for failure */ +int +tor_munmap_file(tor_mmap_t *handle) +{ + if (handle == NULL) + return 0; + + if (handle->data) { + /* This is an ugly cast, but without it, "data" in struct tor_mmap_t would + have to be redefined as non-const. */ + BOOL ok = UnmapViewOfFile( (LPVOID) handle->data); + if (!ok) { + log_warn(LD_FS, "Failed to UnmapViewOfFile() in tor_munmap_file(): %d", + (int)GetLastError()); + } + } + + if (handle->mmap_handle != NULL) + CloseHandle(handle->mmap_handle); + tor_free(handle); + + return 0; +} +#else +#error "cannot implement tor_mmap_file" +#endif /* defined(HAVE_MMAP) || ... || ... */ diff --git a/src/lib/fs/mmap.h b/src/lib/fs/mmap.h new file mode 100644 index 000000000..b0585775f --- /dev/null +++ b/src/lib/fs/mmap.h @@ -0,0 +1,35 @@ +/* Copyright (c) 2003-2004, Roger Dingledine + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2018, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +#ifndef TOR_MMAP_H +#define TOR_MMAP_H + +#include "lib/cc/compat_compiler.h" +#include <stddef.h> + +#ifdef _WIN32 +#include <windef.h> +#endif + +/** Represents an mmaped file. Allocated via tor_mmap_file; freed with + * tor_munmap_file. */ +typedef struct tor_mmap_t { + const char *data; /**< Mapping of the file's contents. */ + size_t size; /**< Size of the file. */ + + /* None of the fields below should be accessed from outside compat.c */ +#ifdef HAVE_MMAP + size_t mapping_size; /**< Size of the actual mapping. (This is this file + * size, rounded up to the nearest page.) */ +#elif defined _WIN32 + HANDLE mmap_handle; +#endif /* defined(HAVE_MMAP) || ... */ + +} tor_mmap_t; + +tor_mmap_t *tor_mmap_file(const char *filename) ATTR_NONNULL((1)); +int tor_munmap_file(tor_mmap_t *handle) ATTR_NONNULL((1)); + +#endif diff --git a/src/lib/fs/path.c b/src/lib/fs/path.c new file mode 100644 index 000000000..68cda6776 --- /dev/null +++ b/src/lib/fs/path.c @@ -0,0 +1,289 @@ +/* Copyright (c) 2003, Roger Dingledine + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2018, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +#include "lib/fs/path.h" +#include "lib/malloc/util_malloc.h" +#include "lib/log/torlog.h" +#include "lib/log/util_bug.h" +#include "lib/string/printf.h" +#include "lib/string/util_string.h" +#include "lib/string/compat_ctype.h" +#include "lib/fs/userdb.h" + +#ifdef HAVE_UNISTD_H +#include <unistd.h> +#endif + +#include <errno.h> +#include <string.h> + +/** Removes enclosing quotes from <b>path</b> and unescapes quotes between the + * enclosing quotes. Backslashes are not unescaped. Return the unquoted + * <b>path</b> on success or 0 if <b>path</b> is not quoted correctly. */ +char * +get_unquoted_path(const char *path) +{ + size_t len = strlen(path); + + if (len == 0) { + return tor_strdup(""); + } + + int has_start_quote = (path[0] == '"'); + int has_end_quote = (len > 0 && path[len-1] == '"'); + if (has_start_quote != has_end_quote || (len == 1 && has_start_quote)) { + return NULL; + } + + char *unquoted_path = tor_malloc(len - has_start_quote - has_end_quote + 1); + char *s = unquoted_path; + size_t i; + for (i = has_start_quote; i < len - has_end_quote; i++) { + if (path[i] == '"' && (i > 0 && path[i-1] == '\')) { + *(s-1) = path[i]; + } else if (path[i] != '"') { + *s++ = path[i]; + } else { /* unescaped quote */ + tor_free(unquoted_path); + return NULL; + } + } + *s = '\0'; + return unquoted_path; +} + +/** Expand any homedir prefix on <b>filename</b>; return a newly allocated + * string. */ +char * +expand_filename(const char *filename) +{ + tor_assert(filename); +#ifdef _WIN32 + /* Might consider using GetFullPathName() as described here: + * http://etutorials.org/Programming/secure+programming/ + * Chapter+3.+Input+Validation/3.7+Validating+Filenames+and+Paths/ + */ + return tor_strdup(filename); +#else /* !(defined(_WIN32)) */ + if (*filename == '~') { + char *home, *result=NULL; + const char *rest; + + if (filename[1] == '/' || filename[1] == '\0') { + home = getenv("HOME"); + if (!home) { + log_warn(LD_CONFIG, "Couldn't find $HOME environment variable while " + "expanding "%s"; defaulting to "".", filename); + home = tor_strdup(""); + } else { + home = tor_strdup(home); + } + rest = strlen(filename)>=2?(filename+2):""; + } else { +#ifdef HAVE_PWD_H + char *username, *slash; + slash = strchr(filename, '/'); + if (slash) + username = tor_strndup(filename+1,slash-filename-1); + else + username = tor_strdup(filename+1); + if (!(home = get_user_homedir(username))) { + log_warn(LD_CONFIG,"Couldn't get homedir for "%s"",username); + tor_free(username); + return NULL; + } + tor_free(username); + rest = slash ? (slash+1) : ""; +#else /* !(defined(HAVE_PWD_H)) */ + log_warn(LD_CONFIG, "Couldn't expand homedir on system without pwd.h"); + return tor_strdup(filename); +#endif /* defined(HAVE_PWD_H) */ + } + tor_assert(home); + /* Remove trailing slash. */ + if (strlen(home)>1 && !strcmpend(home,PATH_SEPARATOR)) { + home[strlen(home)-1] = '\0'; + } + tor_asprintf(&result,"%s"PATH_SEPARATOR"%s",home,rest); + tor_free(home); + return result; + } else { + return tor_strdup(filename); + } +#endif /* defined(_WIN32) */ +} + +/** Return true iff <b>filename</b> is a relative path. */ +int +path_is_relative(const char *filename) +{ + if (filename && filename[0] == '/') + return 0; +#ifdef _WIN32 + else if (filename && filename[0] == '\') + return 0; + else if (filename && strlen(filename)>3 && TOR_ISALPHA(filename[0]) && + filename[1] == ':' && filename[2] == '\') + return 0; +#endif /* defined(_WIN32) */ + else + return 1; +} + +/** Clean up <b>name</b> so that we can use it in a call to "stat". On Unix, + * we do nothing. On Windows, we remove a trailing slash, unless the path is + * the root of a disk. */ +void +clean_fname_for_stat(char *name) +{ +#ifdef _WIN32 + size_t len = strlen(name); + if (!len) + return; + if (name[len-1]=='\' || name[len-1]=='/') { + if (len == 1 || (len==3 && name[1]==':')) + return; + name[len-1]='\0'; + } +#else /* !(defined(_WIN32)) */ + (void)name; +#endif /* defined(_WIN32) */ +} + +/** Modify <b>fname</b> to contain the name of its parent directory. Doesn't + * actually examine the filesystem; does a purely syntactic modification. + * + * The parent of the root director is considered to be iteself. + * + * Path separators are the forward slash (/) everywhere and additionally + * the backslash () on Win32. + * + * Cuts off any number of trailing path separators but otherwise ignores + * them for purposes of finding the parent directory. + * + * Returns 0 if a parent directory was successfully found, -1 otherwise (fname + * did not have any path separators or only had them at the end). + * */ +int +get_parent_directory(char *fname) +{ + char *cp; + int at_end = 1; + tor_assert(fname); +#ifdef _WIN32 + /* If we start with, say, c:, then don't consider that the start of the path + */ + if (fname[0] && fname[1] == ':') { + fname += 2; + } +#endif /* defined(_WIN32) */ + /* Now we want to remove all path-separators at the end of the string, + * and to remove the end of the string starting with the path separator + * before the last non-path-separator. In perl, this would be + * s#[/]*$##; s#/[^/]*$##; + * on a unixy platform. + */ + cp = fname + strlen(fname); + at_end = 1; + while (--cp >= fname) { + int is_sep = (*cp == '/' +#ifdef _WIN32 + || *cp == '\' +#endif + ); + if (is_sep) { + if (cp == fname) { + /* This is the first separator in the file name; don't remove it! */ + cp[1] = '\0'; + return 0; + } + *cp = '\0'; + if (! at_end) + return 0; + } else { + at_end = 0; + } + } + return -1; +} + +#ifndef _WIN32 +/** Return a newly allocated string containing the output of getcwd(). Return + * NULL on failure. (We can't just use getcwd() into a PATH_MAX buffer, since + * Hurd hasn't got a PATH_MAX.) + */ +static char * +alloc_getcwd(void) +{ +#ifdef HAVE_GET_CURRENT_DIR_NAME + /* Glibc makes this nice and simple for us. */ + char *cwd = get_current_dir_name(); + char *result = NULL; + if (cwd) { + /* We make a copy here, in case tor_malloc() is not malloc(). */ + result = tor_strdup(cwd); + raw_free(cwd); // alias for free to avoid tripping check-spaces. + } + return result; +#else /* !(defined(HAVE_GET_CURRENT_DIR_NAME)) */ + size_t size = 1024; + char *buf = NULL; + char *ptr = NULL; + + while (ptr == NULL) { + buf = tor_realloc(buf, size); + ptr = getcwd(buf, size); + + if (ptr == NULL && errno != ERANGE) { + tor_free(buf); + return NULL; + } + + size *= 2; + } + return buf; +#endif /* defined(HAVE_GET_CURRENT_DIR_NAME) */ +} +#endif /* !defined(_WIN32) */ + +/** Expand possibly relative path <b>fname</b> to an absolute path. + * Return a newly allocated string, possibly equal to <b>fname</b>. */ +char * +make_path_absolute(char *fname) +{ +#ifdef _WIN32 + char *absfname_malloced = _fullpath(NULL, fname, 1); + + /* We don't want to assume that tor_free can free a string allocated + * with malloc. On failure, return fname (it's better than nothing). */ + char *absfname = tor_strdup(absfname_malloced ? absfname_malloced : fname); + if (absfname_malloced) raw_free(absfname_malloced); + + return absfname; +#else /* !(defined(_WIN32)) */ + char *absfname = NULL, *path = NULL; + + tor_assert(fname); + + if (fname[0] == '/') { + absfname = tor_strdup(fname); + } else { + path = alloc_getcwd(); + if (path) { + tor_asprintf(&absfname, "%s/%s", path, fname); + tor_free(path); + } else { + /* LCOV_EXCL_START Can't make getcwd fail. */ + /* If getcwd failed, the best we can do here is keep using the + * relative path. (Perhaps / isn't readable by this UID/GID.) */ + log_warn(LD_GENERAL, "Unable to find current working directory: %s", + strerror(errno)); + absfname = tor_strdup(fname); + /* LCOV_EXCL_STOP */ + } + } + return absfname; +#endif /* defined(_WIN32) */ +} diff --git a/src/lib/fs/path.h b/src/lib/fs/path.h new file mode 100644 index 000000000..a3073a99e --- /dev/null +++ b/src/lib/fs/path.h @@ -0,0 +1,24 @@ +/* Copyright (c) 2003-2004, Roger Dingledine + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2018, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +#ifndef TOR_PATH_H +#define TOR_PATH_H + +#include "lib/cc/compat_compiler.h" + +#ifdef _WIN32 +#define PATH_SEPARATOR "\" +#else +#define PATH_SEPARATOR "/" +#endif + +char *get_unquoted_path(const char *path); +char *expand_filename(const char *filename); +int path_is_relative(const char *filename); +void clean_fname_for_stat(char *name); +int get_parent_directory(char *fname); +char *make_path_absolute(char *fname); + +#endif diff --git a/src/lib/fs/userdb.c b/src/lib/fs/userdb.c new file mode 100644 index 000000000..b7abbc781 --- /dev/null +++ b/src/lib/fs/userdb.c @@ -0,0 +1,132 @@ +/* Copyright (c) 2003-2004, Roger Dingledine + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2018, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +#include "lib/fs/userdb.h" + +#ifndef _WIN32 +#include "lib/malloc/util_malloc.h" +#include "lib/log/torlog.h" +#include "lib/log/util_bug.h" + +#include <pwd.h> +#include <stddef.h> +#include <string.h> + +/** Cached struct from the last getpwname() call we did successfully. */ +static struct passwd *passwd_cached = NULL; + +/** Helper: copy a struct passwd object. + * + * We only copy the fields pw_uid, pw_gid, pw_name, pw_dir. Tor doesn't use + * any others, and I don't want to run into incompatibilities. + */ +static struct passwd * +tor_passwd_dup(const struct passwd *pw) +{ + struct passwd *new_pw = tor_malloc_zero(sizeof(struct passwd)); + if (pw->pw_name) + new_pw->pw_name = tor_strdup(pw->pw_name); + if (pw->pw_dir) + new_pw->pw_dir = tor_strdup(pw->pw_dir); + new_pw->pw_uid = pw->pw_uid; + new_pw->pw_gid = pw->pw_gid; + + return new_pw; +} + +#define tor_passwd_free(pw) \ + FREE_AND_NULL(struct passwd, tor_passwd_free_, (pw)) + +/** Helper: free one of our cached 'struct passwd' values. */ +static void +tor_passwd_free_(struct passwd *pw) +{ + if (!pw) + return; + + tor_free(pw->pw_name); + tor_free(pw->pw_dir); + tor_free(pw); +} + +/** Wrapper around getpwnam() that caches result. Used so that we don't need + * to give the sandbox access to /etc/passwd. + * + * The following fields alone will definitely be copied in the output: pw_uid, + * pw_gid, pw_name, pw_dir. Other fields are not present in cached values. + * + * When called with a NULL argument, this function clears storage associated + * with static variables it uses. + **/ +const struct passwd * +tor_getpwnam(const char *username) +{ + struct passwd *pw; + + if (username == NULL) { + tor_passwd_free(passwd_cached); + passwd_cached = NULL; + return NULL; + } + + if ((pw = getpwnam(username))) { + tor_passwd_free(passwd_cached); + passwd_cached = tor_passwd_dup(pw); + log_info(LD_GENERAL, "Caching new entry %s for %s", + passwd_cached->pw_name, username); + return pw; + } + + /* Lookup failed */ + if (! passwd_cached || ! passwd_cached->pw_name) + return NULL; + + if (! strcmp(username, passwd_cached->pw_name)) + return passwd_cached; // LCOV_EXCL_LINE - would need to make getpwnam flaky + + return NULL; +} + +/** Wrapper around getpwnam() that can use cached result from + * tor_getpwnam(). Used so that we don't need to give the sandbox access to + * /etc/passwd. + * + * The following fields alone will definitely be copied in the output: pw_uid, + * pw_gid, pw_name, pw_dir. Other fields are not present in cached values. + */ +const struct passwd * +tor_getpwuid(uid_t uid) +{ + struct passwd *pw; + + if ((pw = getpwuid(uid))) { + return pw; + } + + /* Lookup failed */ + if (! passwd_cached) + return NULL; + + if (uid == passwd_cached->pw_uid) + return passwd_cached; // LCOV_EXCL_LINE - would need to make getpwnam flaky + + return NULL; +} + +/** Allocate and return a string containing the home directory for the + * user <b>username</b>. Only works on posix-like systems. */ +char * +get_user_homedir(const char *username) +{ + const struct passwd *pw; + tor_assert(username); + + if (!(pw = tor_getpwnam(username))) { + log_err(LD_CONFIG,"User "%s" not found.", username); + return NULL; + } + return tor_strdup(pw->pw_dir); +} +#endif /* !defined(_WIN32) */ diff --git a/src/lib/fs/userdb.h b/src/lib/fs/userdb.h new file mode 100644 index 000000000..31c891ede --- /dev/null +++ b/src/lib/fs/userdb.h @@ -0,0 +1,20 @@ +/* Copyright (c) 2003-2004, Roger Dingledine + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2018, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +#ifndef TOR_USERDB_H +#define TOR_USERDB_H + +#include "orconfig.h" + +#ifndef _WIN32 +#include <sys/types.h> + +struct passwd; +const struct passwd *tor_getpwnam(const char *username); +const struct passwd *tor_getpwuid(uid_t uid); +char *get_user_homedir(const char *username); +#endif + +#endif