From 180a9fcdf2c708707783debad45418f488619138 Mon Sep 17 00:00:00 2001 From: Filipe Brandenburger Date: Tue, 2 Jun 2015 21:08:24 -0700 Subject: [PATCH] util: New flag UNQUOTE_UNESCAPE_RELAX for unquote_first_word The new flag UNQUOTE_UNESCAPE_RELAX preserves unrecognized escape sequences verbatim in unquote_first_word, either when it's a trailing backslash (similar to UNQUOTE_RELAX, but in this case keep the extra backslash in the output) or in the middle of a sequence string. Add unit test cases to ensure the new flag works as expected and to prevent regressions from being introduced. Tested with a follow up commit converting config_parse_exec() to start using unquote_first_word, in which case this flags makes it possible to preserve unrecognized escape sequences. Relevant bug: https://bugs.freedesktop.org/show_bug.cgi?id=90794 --- src/shared/util.c | 169 ++++++++++++++++++++++------------------------ src/shared/util.h | 5 +- 2 files changed, 85 insertions(+), 89 deletions(-) diff --git a/src/shared/util.c b/src/shared/util.c index 28e29ff47..46a48c4d6 100644 --- a/src/shared/util.c +++ b/src/shared/util.c @@ -60,8 +60,8 @@ #include /* When we include libgen.h because we need dirname() we immediately - * undefine basename() since libgen.h defines it as a macro to the XDG - * version which is really broken. */ + * undefine basename() since libgen.h defines it as a macro to the POSIX + * version which is really broken. We prefer GNU basename(). */ #include #undef basename @@ -149,6 +149,27 @@ char* endswith(const char *s, const char *postfix) { return (char*) s + sl - pl; } +char* endswith_no_case(const char *s, const char *postfix) { + size_t sl, pl; + + assert(s); + assert(postfix); + + sl = strlen(s); + pl = strlen(postfix); + + if (pl == 0) + return (char*) s + sl; + + if (sl < pl) + return NULL; + + if (strcasecmp(s + sl - pl, postfix) != 0) + return NULL; + + return (char*) s + sl - pl; +} + char* first_word(const char *s, const char *word) { size_t sl, wl; const char *p; @@ -1131,7 +1152,7 @@ static int cunescape_one(const char *p, size_t length, char *ret, uint32_t *ret_ int a, b, c; uint32_t m; - if (length != (size_t) -1 && length < 4) + if (length != (size_t) -1 && length < 3) return -EINVAL; a = unoctchar(p[0]); @@ -2500,7 +2521,7 @@ int fopen_temporary(const char *path, FILE **_f, char **_temp_path) { assert(_f); assert(_temp_path); - r = tempfn_xxxxxx(path, &t); + r = tempfn_xxxxxx(path, NULL, &t); if (r < 0) return r; @@ -2530,7 +2551,7 @@ int symlink_atomic(const char *from, const char *to) { assert(from); assert(to); - r = tempfn_random(to, &t); + r = tempfn_random(to, NULL, &t); if (r < 0) return r; @@ -2573,7 +2594,7 @@ int mknod_atomic(const char *path, mode_t mode, dev_t dev) { assert(path); - r = tempfn_random(path, &t); + r = tempfn_random(path, NULL, &t); if (r < 0) return r; @@ -2594,7 +2615,7 @@ int mkfifo_atomic(const char *path, mode_t mode) { assert(path); - r = tempfn_random(path, &t); + r = tempfn_random(path, NULL, &t); if (r < 0) return r; @@ -4911,7 +4932,7 @@ int bind_remount_recursive(const char *prefix, bool ro) { while ((x = set_steal_first(todo))) { r = set_consume(done, x); - if (r == -EEXIST) + if (r == -EEXIST || r == 0) continue; if (r < 0) return r; @@ -4948,7 +4969,7 @@ int fflush_and_check(FILE *f) { return 0; } -int tempfn_xxxxxx(const char *p, char **ret) { +int tempfn_xxxxxx(const char *p, const char *extra, char **ret) { const char *fn; char *t; @@ -4960,24 +4981,27 @@ int tempfn_xxxxxx(const char *p, char **ret) { * /foo/bar/waldo * * Into this: - * /foo/bar/.#waldoXXXXXX + * /foo/bar/.#waldoXXXXXX */ fn = basename(p); if (!filename_is_valid(fn)) return -EINVAL; - t = new(char, strlen(p) + 2 + 6 + 1); + if (extra == NULL) + extra = ""; + + t = new(char, strlen(p) + 2 + strlen(extra) + 6 + 1); if (!t) return -ENOMEM; - strcpy(stpcpy(stpcpy(mempcpy(t, p, fn - p), ".#"), fn), "XXXXXX"); + strcpy(stpcpy(stpcpy(stpcpy(mempcpy(t, p, fn - p), ".#"), extra), fn), "XXXXXX"); *ret = path_kill_slashes(t); return 0; } -int tempfn_random(const char *p, char **ret) { +int tempfn_random(const char *p, const char *extra, char **ret) { const char *fn; char *t, *x; uint64_t u; @@ -4991,18 +5015,21 @@ int tempfn_random(const char *p, char **ret) { * /foo/bar/waldo * * Into this: - * /foo/bar/.#waldobaa2a261115984a9 + * /foo/bar/.#waldobaa2a261115984a9 */ fn = basename(p); if (!filename_is_valid(fn)) return -EINVAL; - t = new(char, strlen(p) + 2 + 16 + 1); + if (!extra) + extra = ""; + + t = new(char, strlen(p) + 2 + strlen(extra) + 16 + 1); if (!t) return -ENOMEM; - x = stpcpy(stpcpy(mempcpy(t, p, fn - p), ".#"), fn); + x = stpcpy(stpcpy(stpcpy(mempcpy(t, p, fn - p), ".#"), extra), fn); u = random_u64(); for (i = 0; i < 16; i++) { @@ -5016,7 +5043,7 @@ int tempfn_random(const char *p, char **ret) { return 0; } -int tempfn_random_child(const char *p, char **ret) { +int tempfn_random_child(const char *p, const char *extra, char **ret) { char *t, *x; uint64_t u; unsigned i; @@ -5027,14 +5054,17 @@ int tempfn_random_child(const char *p, char **ret) { /* Turns this: * /foo/bar/waldo * Into this: - * /foo/bar/waldo/.#3c2b6219aa75d7d0 + * /foo/bar/waldo/.#3c2b6219aa75d7d0 */ - t = new(char, strlen(p) + 3 + 16 + 1); + if (!extra) + extra = ""; + + t = new(char, strlen(p) + 3 + strlen(extra) + 16 + 1); if (!t) return -ENOMEM; - x = stpcpy(stpcpy(t, p), "/.#"); + x = stpcpy(stpcpy(stpcpy(t, p), "/.#"), extra); u = random_u64(); for (i = 0; i < 16; i++) { @@ -5179,35 +5209,6 @@ int unquote_first_word(const char **p, char **ret, UnquoteFlags flags) { break; - case VALUE_ESCAPE: - if (c == 0) { - if (flags & UNQUOTE_RELAX) - goto finish; - return -EINVAL; - } - - if (!GREEDY_REALLOC(s, allocated, sz+7)) - return -ENOMEM; - - if (flags & UNQUOTE_CUNESCAPE) { - uint32_t u; - - r = cunescape_one(*p, (size_t) -1, &c, &u); - if (r < 0) - return -EINVAL; - - (*p) += r - 1; - - if (c != 0) - s[sz++] = c; /* normal explicit char */ - else - sz += utf8_encode_unichar(s + sz, u); /* unicode chars we'll encode as utf8 */ - } else - s[sz++] = c; - - state = VALUE; - break; - case SINGLE_QUOTE: if (c == 0) { if (flags & UNQUOTE_RELAX) @@ -5226,35 +5227,6 @@ int unquote_first_word(const char **p, char **ret, UnquoteFlags flags) { break; - case SINGLE_QUOTE_ESCAPE: - if (c == 0) { - if (flags & UNQUOTE_RELAX) - goto finish; - return -EINVAL; - } - - if (!GREEDY_REALLOC(s, allocated, sz+7)) - return -ENOMEM; - - if (flags & UNQUOTE_CUNESCAPE) { - uint32_t u; - - r = cunescape_one(*p, (size_t) -1, &c, &u); - if (r < 0) - return -EINVAL; - - (*p) += r - 1; - - if (c != 0) - s[sz++] = c; - else - sz += utf8_encode_unichar(s + sz, u); - } else - s[sz++] = c; - - state = SINGLE_QUOTE; - break; - case DOUBLE_QUOTE: if (c == 0) return -EINVAL; @@ -5271,33 +5243,56 @@ int unquote_first_word(const char **p, char **ret, UnquoteFlags flags) { break; + case SINGLE_QUOTE_ESCAPE: case DOUBLE_QUOTE_ESCAPE: + case VALUE_ESCAPE: + if (!GREEDY_REALLOC(s, allocated, sz+7)) + return -ENOMEM; + if (c == 0) { + if ((flags & UNQUOTE_CUNESCAPE_RELAX) && + (state == VALUE_ESCAPE || flags & UNQUOTE_RELAX)) { + /* If we find an unquoted trailing backslash and we're in + * UNQUOTE_CUNESCAPE_RELAX mode, keep it verbatim in the + * output. + * + * Unbalanced quotes will only be allowed in UNQUOTE_RELAX + * mode, UNQUOTE_CUNESCAP_RELAX mode does not allow them. + */ + s[sz++] = '\\'; + goto finish; + } if (flags & UNQUOTE_RELAX) goto finish; return -EINVAL; } - if (!GREEDY_REALLOC(s, allocated, sz+7)) - return -ENOMEM; - if (flags & UNQUOTE_CUNESCAPE) { uint32_t u; r = cunescape_one(*p, (size_t) -1, &c, &u); - if (r < 0) + if (r < 0) { + if (flags & UNQUOTE_CUNESCAPE_RELAX) { + s[sz++] = '\\'; + s[sz++] = c; + goto end_escape; + } return -EINVAL; + } (*p) += r - 1; if (c != 0) - s[sz++] = c; + s[sz++] = c; /* normal explicit char */ else - sz += utf8_encode_unichar(s + sz, u); + sz += utf8_encode_unichar(s + sz, u); /* unicode chars we'll encode as utf8 */ } else s[sz++] = c; - state = DOUBLE_QUOTE; +end_escape: + state = (state == SINGLE_QUOTE_ESCAPE) ? SINGLE_QUOTE : + (state == DOUBLE_QUOTE_ESCAPE) ? DOUBLE_QUOTE : + VALUE; break; case SPACE: @@ -5499,7 +5494,7 @@ int openpt_in_namespace(pid_t pid, int flags) { if (recvmsg(pair[0], &mh, MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) < 0) return -errno; - for (cmsg = CMSG_FIRSTHDR(&mh); cmsg; cmsg = CMSG_NXTHDR(&mh, cmsg)) + CMSG_FOREACH(cmsg, &mh) if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_RIGHTS) { int *fds; unsigned n_fds; @@ -5887,7 +5882,7 @@ void cmsg_close_all(struct msghdr *mh) { assert(mh); - for (cmsg = CMSG_FIRSTHDR(mh); cmsg; cmsg = CMSG_NXTHDR(mh, cmsg)) + CMSG_FOREACH(cmsg, mh) if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_RIGHTS) close_many((int*) CMSG_DATA(cmsg), (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int)); } diff --git a/src/shared/util.h b/src/shared/util.h index edcfa35c5..d465d6908 100644 --- a/src/shared/util.h +++ b/src/shared/util.h @@ -1002,8 +1002,9 @@ int is_symlink(const char *path); int is_dir(const char *path, bool follow); typedef enum UnquoteFlags{ - UNQUOTE_RELAX = 1, - UNQUOTE_CUNESCAPE = 2, + UNQUOTE_RELAX = 1, + UNQUOTE_CUNESCAPE = 2, + UNQUOTE_CUNESCAPE_RELAX = 4, } UnquoteFlags; int unquote_first_word(const char **p, char **ret, UnquoteFlags flags); -- 2.30.2