httpd: replace shell-based dir indexer cgi example with C-based one.

This commit is contained in:
Denis Vlasenko 2007-08-22 10:38:44 +00:00
parent 72b6a65b2f
commit 7642998190
2 changed files with 331 additions and 50 deletions

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@ -1,50 +0,0 @@
#!/bin/sh
# This CGI creates directory index.
# Put it into cgi-bin/index.cgi and chmod 0755.
#
# Problems:
# * Unsafe wrt weird filenames with <>"'& etc...
# * Not efficient: calls stat (program, not syscall) for each file
# * Probably requires bash
#
# If you want speed and safety, you need to code it in C
# Must start with '/'
test "${QUERY_STRING:0:1}" = "/" || exit 1
# /../ is not allowed
test "${QUERY_STRING%/../*}" = "$QUERY_STRING" || exit 1
test "${QUERY_STRING%/..}" = "$QUERY_STRING" || exit 1
# Outta cgi-bin...
cd .. 2>/dev/null || exit 1
# Strip leading '/', go to target dir
cd "${QUERY_STRING:1}" 2>/dev/null || exit 1
f=`dirname "$QUERY_STRING"`
test "$f" = "/" && f=""
printf "%s" \
$'HTTP/1.0 200 OK\r\n'\
$'Content-type: text/html\r\n\r\n'\
"<html><head><title>Index of $QUERY_STRING</title></head>"$'\r\n'\
"<body><h1>Index of $QUERY_STRING</h1><pre>"$'\r\n'\
$'<table width=100%>\r\n'\
$'<col><col><col width=0*>\r\n'\
$'<tr><th>Name<th align=right>Last modified<th align=right>Size\r\n'\
\
"<tr><td><a href='$f/'>..</a><td><td>"$'\r\n'
IFS='#'
for f in *; do
# Guard against empty dirs...
test -e "$f" && \
stat -c "%F#%s#%z" "$f" | {
read type size cdt junk
dir=''
test "$type" = "directory" && dir='/'
cdt="${cdt//.*}" # no fractional seconds
cdt="${cdt// /&nbsp;}" # prevent wrapping around space
printf "%s" "<tr><td><a href='$f$dir'>$f</a><td align=right>$cdt<td align=right>$size"$'\r\n'
}
done
printf "</table></pre><hr></body></html>"$'\r\n'

331
networking/httpd_indexcgi.c Normal file
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/*
* Copyright (c) 2007 Denys Vlasenko <vda.linux@googlemail.com>
*
* Licensed under GPLv2, see file LICENSE in this tarball for details.
*/
/*
* This program is a CGI application. It creates directory index page.
* Put it into cgi-bin/index.cgi and chmod 0755.
*/
/* Build a-la
i486-linux-uclibc-gcc \
-static -static-libgcc \
-D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 \
-Wall -Wshadow -Wwrite-strings -Wundef -Wstrict-prototypes -Werror \
-Wold-style-definition -Wdeclaration-after-statement -Wno-pointer-sign \
-Wmissing-prototypes -Wmissing-declarations \
-Os -fno-builtin-strlen -finline-limit=0 -fomit-frame-pointer \
-ffunction-sections -fdata-sections -fno-guess-branch-probability \
-funsigned-char \
-falign-functions=1 -falign-jumps=1 -falign-labels=1 -falign-loops=1 \
-march=i386 -mpreferred-stack-boundary=2 \
-Wl,-Map -Wl,link.map -Wl,--warn-common -Wl,--sort-common -Wl,--gc-sections \
httpd_indexcgi.c -o index.cgi
Size (approximate):
text data bss dec hex filename
22642 160 3052 25854 64fe index.cgi
*/
/* TODO: get rid of printf's: printf code is more than 50%
* of the entire executable when built against static uclibc */
#include <sys/types.h>
#include <sys/stat.h>
#include <errno.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <stdio.h>
#include <dirent.h>
#include <time.h>
/* Appearance of the table is controlled by style sheet *ONLY*,
* formatting code uses <TAG class=CLASS> to apply style
* to elements. Edit stylesheet to your liking and recompile. */
static const char str_header[] =
"" /* Additional headers (currently none) */
"\r\n" /* Mandatory empty line after headers */
"<html><head><title>Index of %s</title>" "\n"
"<style>" "\n"
"table {" "\n"
" width: 100%%;" "\n"
" background-color: #fff5ee;" "\n"
" border-width: 1px;" /* 1px 1px 1px 1px; */ "\n"
" border-spacing: 2px;" "\n"
" border-style: solid;" /* solid solid solid solid; */ "\n"
" border-color: black;" /* black black black black; */ "\n"
" border-collapse: collapse;" "\n"
"}" "\n"
"th {" "\n"
" border-width: 1px;" /* 1px 1px 1px 1px; */ "\n"
" padding: 1px;" /* 1px 1px 1px 1px; */ "\n"
" border-style: solid;" /* solid solid solid solid; */ "\n"
" border-color: black;" /* black black black black; */ "\n"
"}" "\n"
"td {" "\n"
/* top right bottom left */
" border-width: 0px 1px 0px 1px;" "\n"
" padding: 1px;" /* 1px 1px 1px 1px; */ "\n"
" border-style: solid;" /* solid solid solid solid; */ "\n"
" border-color: black;" /* black black black black; */ "\n"
"}" "\n"
"tr.hdr { background-color:#eee5de; }" "\n"
"tr.o { background-color:#ffffff; }" "\n"
/* tr.e { ... } - for even rows (currently none) */
"tr.foot { background-color:#eee5de; }" "\n"
"th.cnt { text-align:left; }" "\n"
"th.sz { text-align:right; }" "\n"
"th.dt { text-align:right; }" "\n"
"td.sz { text-align:right; }" "\n"
"td.dt { text-align:right; }" "\n"
"col.nm { width: 98%%; }" "\n"
"col.sz { width: 1%%; }" "\n"
"col.dt { width: 1%%; }" "\n"
"</style>" "\n"
"</head>" "\n"
"<body>" "\n"
"<h1>Index of %s</h1>" "\n"
"" "\n"
"<table>" "\n"
"<col class=nm><col class=sz><col class=dt>" "\n"
"<tr class=hdr><th class=cnt>Name<th class=sz>Size<th class=dt>Last modified" "\n"
;
static const char str_footer[] =
"<tr class=foot><th class=cnt>Files: %u, directories: %u<th class=sz>%llu<th class=dt>&nbsp;" "\n"
/* "</table></body></html>" - why bother? */
;
static int bad_url_char(unsigned c)
{
return (c - '0') > 9 /* not a digit */
&& ((c|0x20) - 'a') > 26 /* not A-Z or a-z */
&& !strchr("._-+@", c);
}
static char *url_encode(const char *name)
{
int i;
int size = 0;
int len = strlen(name);
char *p, *result;
i = 0;
while (name[i]) {
if (bad_url_char((unsigned)name[i]))
size++;
i++;
}
/* No %xx needed! */
if (!size)
return (char*)name;
/* Each %xx requires 2 additional chars */
size = size * 2 + len + 1;
p = result = malloc(size);
i = 0;
while (name[i]) {
*p = name[i];
if (bad_url_char((unsigned)name[i])) {
*p++ = '%';
*p++ = "0123456789ABCDEF"[(uint8_t)(name[i]) >> 4];
*p = "0123456789ABCDEF"[(uint8_t)(name[i]) & 0xf];
}
p++;
i++;
}
*p = 0;
return result;
}
static char *html_encode(const char *name)
{
int i;
int size = 0;
int len = strlen(name);
char *p, *result;
i = 0;
while (name[i]) {
if (name[i] == '<'
|| name[i] == '>'
|| name[i] == '&'
) {
size++;
}
i++;
}
/* No &lt; etc needed! */
if (!size)
return (char*)name;
/* &amp; requires 4 additional chars */
size = size * 4 + len + 1;
p = result = malloc(size);
i = 0;
while (name[i]) {
char c;
*p = c = name[i++];
if (c == '<')
strcpy(p, "&lt;");
else if (c == '>')
strcpy(p, "&gt;");
else if (c == '&')
strcpy(++p, "amp;");
else {
p++;
continue;
}
p += 4;
}
*p = 0;
return result;
}
typedef struct dir_list_t {
char *dl_name;
mode_t dl_mode;
off_t dl_size;
time_t dl_mtime;
} dir_list_t;
static int compare_dl(dir_list_t *a, dir_list_t *b)
{
if (strcmp(a->dl_name, "..") == 0) {
/* ".." is 'less than' any other dir entry */
return -1;
}
if (strcmp(b->dl_name, "..") == 0) {
return 1;
}
if (S_ISDIR(a->dl_mode) != S_ISDIR(b->dl_mode)) {
/* 1 if b is a dir (and thus a is 'after' b, a > b),
* else -1 (a < b)*/
return (S_ISDIR(b->dl_mode) != 0) ? 1 : -1;
}
return strcmp(a->dl_name, b->dl_name);
}
int main(void)
{
dir_list_t *dir_list;
dir_list_t *cdir;
unsigned dir_list_count;
unsigned count_dirs;
unsigned count_files;
unsigned long long size_total;
int odd;
DIR *dirp;
char *QUERY_STRING;
QUERY_STRING = getenv("QUERY_STRING");
if (!QUERY_STRING
|| QUERY_STRING[0] != '/'
|| strstr(QUERY_STRING, "/../")
|| strcmp(strrchr(QUERY_STRING, '/'), "/..") == 0
) {
return 1;
}
if (chdir("..")
|| (QUERY_STRING[1] && chdir(QUERY_STRING + 1))
) {
return 1;
}
dirp = opendir(".");
if (!dirp)
return 1;
dir_list = NULL;
dir_list_count = 0;
while (1) {
struct dirent *dp;
struct stat sb;
dp = readdir(dirp);
if (!dp)
break;
if (dp->d_name[0] == '.' && !dp->d_name[1])
continue;
if (stat(dp->d_name, &sb) != 0)
continue;
dir_list = realloc(dir_list, (dir_list_count + 1) * sizeof(dir_list[0]));
dir_list[dir_list_count].dl_name = strdup(dp->d_name);
dir_list[dir_list_count].dl_mode = sb.st_mode;
dir_list[dir_list_count].dl_size = sb.st_size;
dir_list[dir_list_count].dl_mtime = sb.st_mtime;
dir_list_count++;
}
qsort(dir_list, dir_list_count, sizeof(dir_list[0]), (void*)compare_dl);
/* Guard against directories wit &, > etc */
QUERY_STRING = html_encode(QUERY_STRING);
printf(str_header, QUERY_STRING, QUERY_STRING);
odd = 0;
count_dirs = 0;
count_files = 0;
size_total = 0;
cdir = dir_list;
while (dir_list_count--) {
char size_str[sizeof(long long) * 3];
const char *slash_if_dir;
struct tm *tm;
char *href;
char *filename;
char datetime_str[sizeof("2000-02-02&nbsp;02:02:02")];
slash_if_dir = "/";
if (S_ISDIR(cdir->dl_mode)) {
count_dirs++;
size_str[0] = '\0';
} else if (S_ISREG(cdir->dl_mode)) {
count_files++;
size_total += cdir->dl_size;
slash_if_dir++; /* points to "" now */
sprintf(size_str, "%llu", (unsigned long long)(cdir->dl_size));
} else
goto next;
href = url_encode(cdir->dl_name); /* %20 etc */
filename = html_encode(cdir->dl_name); /* &lt; etc */
tm = gmtime(&cdir->dl_mtime);
sprintf(datetime_str, "%04u-%02u-%02u&nbsp;%02u:%02u:%02u",
(unsigned)(1900 + tm->tm_year),
(unsigned)(tm->tm_mon + 1),
(unsigned)(tm->tm_mday),
(unsigned)(tm->tm_hour),
(unsigned)(tm->tm_min),
(unsigned)(tm->tm_sec)
);
printf("<tr class=%c><td class=nm><a href='%s%s'>%s%s</a><td class=sz>%s<td class=dt>%s\n",
odd ? 'o' : 'e',
href, slash_if_dir,
filename, slash_if_dir,
size_str,
datetime_str
);
if (cdir->dl_name != href)
free(href);
if (cdir->dl_name != filename)
free(filename);
odd = 1 - odd;
next:
cdir++;
}
/* count_dirs - 1: we don't want to count ".." */
printf(str_footer, count_files, count_dirs - 1, size_total);
return 0;
}