diff options
| -rw-r--r-- | include/libbb.h | 6 | ||||
| -rw-r--r-- | libbb/fgets_str.c | 26 | ||||
| -rw-r--r-- | libbb/read.c | 6 | ||||
| -rw-r--r-- | networking/ftpd.c | 65 |
4 files changed, 81 insertions, 22 deletions
diff --git a/include/libbb.h b/include/libbb.h index bc47ce7..8ea493b 100644 --- a/include/libbb.h +++ b/include/libbb.h @@ -594,9 +594,9 @@ extern ssize_t open_read_close(const char *filename, void *buf, size_t maxsz) FA // Reads byte-by-byte. Useful when it is important to not read ahead. // Bytes are appended to pfx (which must be malloced, or NULL). extern char *xmalloc_reads(int fd, char *pfx, size_t *maxsz_p) FAST_FUNC; -/* Reads block up to *maxsz_p (default: MAX_INT(ssize_t)) */ +/* Reads block up to *maxsz_p (default: INT_MAX - 4095) */ extern void *xmalloc_read(int fd, size_t *maxsz_p) FAST_FUNC; -/* Returns NULL if file can't be opened */ +/* Returns NULL if file can't be opened (default max size: INT_MAX - 4095) */ extern void *xmalloc_open_read_close(const char *filename, size_t *maxsz_p) FAST_FUNC; /* Autodetects .gz etc */ extern int open_zipped(const char *fname) FAST_FUNC; @@ -619,6 +619,8 @@ extern char *bb_get_chunk_from_file(FILE *file, int *end) FAST_FUNC; extern char *bb_get_chunk_with_continuation(FILE *file, int *end, int *lineno) FAST_FUNC; /* Reads up to (and including) TERMINATING_STRING: */ extern char *xmalloc_fgets_str(FILE *file, const char *terminating_string) FAST_FUNC; +/* Same, with limited max size, and returns the length (excluding NUL): */ +extern char *xmalloc_fgets_str_len(FILE *file, const char *terminating_string, size_t *maxsz_p) FAST_FUNC; /* Chops off TERMINATING_STRING from the end: */ extern char *xmalloc_fgetline_str(FILE *file, const char *terminating_string) FAST_FUNC; /* Reads up to (and including) "\n" or NUL byte: */ diff --git a/libbb/fgets_str.c b/libbb/fgets_str.c index 8026a15..3fe61cd 100644 --- a/libbb/fgets_str.c +++ b/libbb/fgets_str.c @@ -10,7 +10,7 @@ #include "libbb.h" -static char *xmalloc_fgets_internal(FILE *file, const char *terminating_string, int chop_off) +static char *xmalloc_fgets_internal(FILE *file, const char *terminating_string, int chop_off, size_t *maxsz_p) { char *linebuf = NULL; const int term_length = strlen(terminating_string); @@ -18,6 +18,7 @@ static char *xmalloc_fgets_internal(FILE *file, const char *terminating_string, int linebufsz = 0; int idx = 0; int ch; + size_t maxsz = *maxsz_p; while (1) { ch = fgetc(file); @@ -30,6 +31,11 @@ static char *xmalloc_fgets_internal(FILE *file, const char *terminating_string, if (idx >= linebufsz) { linebufsz += 200; linebuf = xrealloc(linebuf, linebufsz); + if (idx >= maxsz) { + linebuf[idx] = ch; + idx++; + break; + } } linebuf[idx] = ch; @@ -48,6 +54,7 @@ static char *xmalloc_fgets_internal(FILE *file, const char *terminating_string, /* Grow/shrink *first*, then store NUL */ linebuf = xrealloc(linebuf, idx + 1); linebuf[idx] = '\0'; + *maxsz_p = idx; return linebuf; } @@ -57,10 +64,23 @@ static char *xmalloc_fgets_internal(FILE *file, const char *terminating_string, * Return NULL if EOF is reached immediately. */ char* FAST_FUNC xmalloc_fgets_str(FILE *file, const char *terminating_string) { - return xmalloc_fgets_internal(file, terminating_string, 0); + size_t maxsz = INT_MAX - 4095; + return xmalloc_fgets_internal(file, terminating_string, 0, &maxsz); +} + +char* FAST_FUNC xmalloc_fgets_str_len(FILE *file, const char *terminating_string, size_t *maxsz_p) +{ + size_t maxsz; + + if (!maxsz_p) { + maxsz = INT_MAX - 4095; + maxsz_p = &maxsz; + } + return xmalloc_fgets_internal(file, terminating_string, 0, maxsz_p); } char* FAST_FUNC xmalloc_fgetline_str(FILE *file, const char *terminating_string) { - return xmalloc_fgets_internal(file, terminating_string, 1); + size_t maxsz = INT_MAX - 4095; + return xmalloc_fgets_internal(file, terminating_string, 1, &maxsz); } diff --git a/libbb/read.c b/libbb/read.c index 815007c..37503e8 100644 --- a/libbb/read.c +++ b/libbb/read.c @@ -141,7 +141,7 @@ char* FAST_FUNC xmalloc_reads(int fd, char *buf, size_t *maxsz_p) { char *p; size_t sz = buf ? strlen(buf) : 0; - size_t maxsz = maxsz_p ? *maxsz_p : MAXINT(size_t); + size_t maxsz = maxsz_p ? *maxsz_p : (INT_MAX - 4095); goto jump_in; while (sz < maxsz) { @@ -198,7 +198,7 @@ void* FAST_FUNC xmalloc_read(int fd, size_t *maxsz_p) size_t to_read; struct stat st; - to_read = maxsz_p ? *maxsz_p : MAXINT(ssize_t); /* max to read */ + to_read = maxsz_p ? *maxsz_p : (INT_MAX - 4095); /* max to read */ /* Estimate file size */ st.st_size = 0; /* in case fstat fails, assume 0 */ @@ -262,7 +262,7 @@ void* FAST_FUNC xmalloc_open_read_close(const char *filename, size_t *maxsz_p) len = lseek(fd, 0, SEEK_END) | 0x3ff; /* + up to 1k */ if (len != (off_t)-1) { xlseek(fd, 0, SEEK_SET); - size = maxsz_p ? *maxsz_p : INT_MAX; + size = maxsz_p ? *maxsz_p : (INT_MAX - 4095); if (len < size) size = len; } diff --git a/networking/ftpd.c b/networking/ftpd.c index 6630db7..39a4d18 100644 --- a/networking/ftpd.c +++ b/networking/ftpd.c @@ -972,23 +972,60 @@ cmdio_get_cmd_and_arg(void) free(G.ftp_cmd); len = 8 * 1024; /* Paranoia. Peer may send 1 gigabyte long cmd... */ - G.ftp_cmd = cmd = xmalloc_reads(STDIN_FILENO, NULL, &len); + G.ftp_cmd = cmd = xmalloc_fgets_str_len(stdin, "\r\n", &len); if (!cmd) exit(0); -/* TODO: de-escape telnet here: 0xff,0xff => 0xff */ -/* RFC959 says that ABOR, STAT, QUIT may be sent even during - * data transfer, and may be preceded by telnet's "Interrupt Process" - * code (two-byte sequence 255,244) and then by telnet "Synch" code - * 255,242 (byte 242 is sent with TCP URG bit using send(MSG_OOB) - * and may generate SIGURG on our side. See RFC854). - * So far we don't support that (may install SIGURG handler if we'd want to), - * but we need to at least remove 255,xxx pairs. lftp sends those. */ - - /* Trailing '\n' is already stripped, strip '\r' */ - len = strlen(cmd) - 1; - if ((ssize_t)len >= 0 && cmd[len] == '\r') - cmd[len--] = '\0'; + /* De-escape telnet: 0xff,0xff => 0xff */ + /* RFC959 says that ABOR, STAT, QUIT may be sent even during + * data transfer, and may be preceded by telnet's "Interrupt Process" + * code (two-byte sequence 255,244) and then by telnet "Synch" code + * 255,242 (byte 242 is sent with TCP URG bit using send(MSG_OOB) + * and may generate SIGURG on our side. See RFC854). + * So far we don't support that (may install SIGURG handler if we'd want to), + * but we need to at least remove 255,xxx pairs. lftp sends those. */ + /* Then de-escape FTP: NUL => '\n' */ + /* Testing for \xff: + * Create file named '\xff': echo Hello >`echo -ne "\xff"` + * Try to get it: ftpget -v 127.0.0.1 Eff `echo -ne "\xff\xff"` + * (need "\xff\xff" until ftpget applet is fixed to do escaping :) + * Testing for embedded LF: + * LF_HERE=`echo -ne "LF\nHERE"` + * echo Hello >"$LF_HERE" + * ftpget -v 127.0.0.1 LF_HERE "$LF_HERE" + */ + { + int dst, src; + + /* Strip "\r\n" if it is there */ + if (len != 0 && cmd[len - 1] == '\n') { + len--; + if (len != 0 && cmd[len - 1] == '\r') + len--; + cmd[len] = '\0'; + } + src = strchrnul(cmd, 0xff) - cmd; + /* 99,99% there are neither NULs nor 255s and src == len */ + if (src < len) { + dst = src; + do { + if ((unsigned char)(cmd[src]) == 255) { + src++; + /* 255,xxx - skip 255 */ + if ((unsigned char)(cmd[src]) != 255) { + /* 255,!255 - skip both */ + src++; + continue; + } + /* 255,255 - retain one 255 */ + } + /* NUL => '\n' */ + cmd[dst++] = cmd[src] ? cmd[src] : '\n'; + src++; + } while (src < len); + cmd[dst] = '\0'; + } + } if (G.verbose > 1) verbose_log(cmd); |