suckless-quark/quark.c
Hiltjo Posthuma c00949d37d quark.1: add manpage
quark.c: alphabeticly sort options, like in the manpage.
Makefile: add manpage rule to Makefile and fix make dist.
2014-08-20 20:42:58 +02:00

692 lines
16 KiB
C

/* See LICENSE file for license details. */
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <grp.h>
#include <netdb.h>
#include <pwd.h>
#include <signal.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include "arg.h"
char *argv0;
#define LENGTH(x) (sizeof x / sizeof x[0])
#define MAXBUFLEN 1024
#define MIN(x,y) ((x) < (y) ? (x) : (y))
#define HttpOk "200 OK"
#define HttpMoved "301 Moved Permanently"
#define HttpNotModified "304 Not Modified"
#define HttpForbidden "403 Forbidden"
#define HttpNotFound "404 Not Found"
#define texthtml "text/html"
enum {
GET = 4,
HEAD = 5,
};
typedef struct {
const char *extension;
const char *mimetype;
} MimeType;
typedef struct {
int type;
int fd;
} Request;
enum {
HEADER,
CONTENTLEN,
LOCATION,
CONTENTTYPE,
MODIFIED
};
static const char *resentry[] = {
[HEADER] = "HTTP/1.1 %s\r\n"
"Connection: close\r\n"
"Date: %s\r\n"
"Server: quark-"VERSION"\r\n",
[CONTENTLEN] = "Content-Length: %lu\r\n",
[LOCATION] = "Location: %s%s\r\n",
[CONTENTTYPE] = "Content-Type: %s\r\n",
[MODIFIED] = "Last-Modified: %s\r\n"
};
static char *tstamp(time_t t);
static int writedata(const char *buf, size_t buflen);
static int writetext(const char *buf);
static void atomiclog(int fd, const char *errstr, va_list ap);
static void logmsg(const char *errstr, ...);
static void logerrmsg(const char *errstr, ...);
static void die(const char *errstr, ...);
static int putresentry(int type, ...);
static void responsefiledata(int fd, off_t size);
static void responsefile(void);
static void responsedirdata(struct dirent **e, int len);
static void responsedir(void);
static void responsecgi(void);
static void response(void);
static int getreqentry(char *name, char *target, size_t targetlen, char *breakchars);
static int request(void);
static void serve(int fd);
static void sighandler(int sig);
#include "config.h"
static char location[256];
static int running = 1;
static int status;
static char host[NI_MAXHOST];
static char reqbuf[MAXBUFLEN];
static char resbuf[MAXBUFLEN];
static char reqhost[256];
static char reqmod[256];
static int fd = -1;
static Request req;
static int allowdirlist = 0;
char *
tstamp(time_t t) {
static char res[30];
if (!t)
t = time(NULL);
strftime(res, sizeof res, "%a, %d %b %Y %H:%M:%S GMT", gmtime(&t));
return res;
}
int
writedata(const char *buf, size_t buf_len) {
ssize_t r, offset;
for (offset = 0; offset < buf_len; offset += r) {
if ((r = write(req.fd, buf + offset, buf_len - offset)) == -1) {
logerrmsg("client %s closed connection\n", host);
return -1;
}
}
return 0;
}
int
writetext(const char *buf) {
return writedata(buf, strlen(buf));
}
void
atomiclog(int fd, const char *errstr, va_list ap) {
static char buf[512];
size_t n;
/* assemble the message in buf and write it in one pass
to avoid interleaved concurrent writes on a shared fd. */
n = snprintf(buf, sizeof buf, "%s\t", tstamp(0));
n += vsnprintf(buf + n, sizeof buf - n, errstr, ap);
if (n >= sizeof buf)
n = sizeof buf - 1;
write(fd, buf, n);
}
void
logmsg(const char *errstr, ...) {
va_list ap;
va_start(ap, errstr);
atomiclog(STDOUT_FILENO, errstr, ap);
va_end(ap);
}
void
logerrmsg(const char *errstr, ...) {
va_list ap;
va_start(ap, errstr);
atomiclog(STDERR_FILENO, errstr, ap);
va_end(ap);
}
void
die(const char *errstr, ...) {
va_list ap;
va_start(ap, errstr);
atomiclog(STDERR_FILENO, errstr, ap);
va_end(ap);
exit(EXIT_FAILURE);
}
int
putresentry(int type, ...) {
va_list ap;
va_start(ap, type);
if (vsnprintf(resbuf, MAXBUFLEN, resentry[type], ap) >= MAXBUFLEN) {
logerrmsg("vsnprintf failed, buffer size exceeded");
return -1;
}
va_end(ap);
return writetext(resbuf);
}
void
responsefiledata(int fd, off_t size) {
char buf[BUFSIZ];
ssize_t n, m = 0, size_in;
for (; (n = read(fd, buf, MIN(size, sizeof buf))) > 0; size -= n)
for(size_in = n; (m = write(req.fd, buf, size_in)) > 0; size_in -= m);
if (m == -1 && errno != EPIPE)
logerrmsg("error writing to client %s: %s\n", host, strerror(errno));
if (n == -1)
logerrmsg("error reading from file: %s\n", strerror(errno));
}
void
responsefile(void) {
const char *mimetype = "application/octet-stream";
char mod[30], *p;
int r, ffd;
struct stat st;
if ((r = stat(reqbuf, &st)) == -1 || (ffd = open(reqbuf, O_RDONLY)) == -1) {
/* file not found */
if (putresentry(HEADER, HttpNotFound, tstamp(0))
|| putresentry(CONTENTTYPE, texthtml))
return;
status = 404;
if (req.type == GET)
writetext("\r\n<html><body>"HttpNotFound"</body></html>\r\n");
} else {
snprintf(mod, sizeof(mod), "%s", tstamp(st.st_mtim.tv_sec));
/* check if modified */
if (!strcmp(reqmod, mod)
&& !putresentry(HEADER, HttpNotModified, tstamp(0))) {
/* not modified, we're done here*/
status = 304;
} else {
/* determine mime-type */
if ((p = strrchr(reqbuf, '.'))) {
p++;
for (r = 0; r < LENGTH(servermimes); r++)
if (!strcmp(servermimes[r].extension, p)) {
mimetype = servermimes[r].mimetype;
break;
}
}
/* serve file */
if (putresentry(HEADER, HttpOk, tstamp(0))
|| putresentry(MODIFIED, mod)
|| putresentry(CONTENTLEN, st.st_size)
|| putresentry(CONTENTTYPE, mimetype))
return;
status = 200;
if (req.type == GET && !writetext("\r\n"))
responsefiledata(ffd, st.st_size);
}
close(ffd);
}
}
void
responsedirdata(struct dirent **e, int len) {
int n;
if (putresentry(HEADER, HttpOk, tstamp(0))
|| putresentry(CONTENTTYPE, texthtml))
return;
status = 200;
if (req.type == GET) {
if (writetext("\r\n<html><body><a href=\"..\">..</a><br/>\r\n"))
return;
for(n = 0; n < len; n++) {
if (e[n]->d_name[0] == '.') /* ignore hidden files, ., .. */
continue;
if (snprintf(resbuf, MAXBUFLEN, "<a href=\"%s%s\">%s</a><br/>\r\n",
reqbuf, e[n]->d_name, e[n]->d_name) >= MAXBUFLEN)
{
logerrmsg("snprintf failed, buffer sizeof exceeded");
return;
}
if (writetext(resbuf))
return;
}
writetext("</body></html>\r\n");
}
}
void
responsedir(void) {
size_t len = strlen(reqbuf);
struct dirent **namelist = NULL;
int n;
if (len > 0 && (reqbuf[len - 1] != '/') && (len + 1 < MAXBUFLEN)) {
/* add directory terminator if necessary */
reqbuf[len] = '/';
reqbuf[len + 1] = 0;
if (putresentry(HEADER, HttpMoved, tstamp(0))
|| putresentry(LOCATION, location, reqbuf)
|| putresentry(CONTENTTYPE, texthtml))
return;
status = 301;
reqbuf[len] = 0;
if (req.type == GET)
writetext("\r\n<html><body>"HttpMoved"</a></body></html>\r\n");
return;
}
if (len + strlen(docindex) + 1 < MAXBUFLEN)
memcpy(reqbuf + len, docindex, strlen(docindex) + 1);
if (access(reqbuf, R_OK) == -1) { /* directory mode */
reqbuf[len] = 0; /* cut off docindex again */
if(!allowdirlist) {
if (putresentry(HEADER, HttpForbidden, tstamp(0))
|| putresentry(CONTENTTYPE, texthtml))
return;
status = 403;
if (req.type == GET)
writetext("\r\n<html><body>"HttpForbidden"</body></html>\r\n");
return;
}
if ((n = scandir(reqbuf, &namelist, NULL, alphasort)) >= 0) {
responsedirdata(namelist, n);
free(namelist);
} else {
logerrmsg("client %s requests %s but scandir failed: %s\n",
host, reqbuf, strerror(errno));
}
} else {
responsefile(); /* docindex */
}
}
void
responsecgi(void) {
FILE *cgi;
size_t r, linesiz = 0;
char *q, *line = NULL, *statusline = HttpOk;
ssize_t linelen;
if (req.type == GET)
setenv("REQUEST_METHOD", "GET", 1);
else if (req.type == HEAD)
setenv("REQUEST_METHOD", "HEAD", 1);
else
return;
if (*reqhost)
setenv("SERVER_NAME", reqhost, 1);
if((q = strchr(reqbuf, '?'))) {
setenv("QUERY_STRING", q + 1, 1);
*q = '\0';
setenv("PATH_INFO", reqbuf, 1);
*q = '?';
} else {
setenv("QUERY_STRING", "", 1);
setenv("PATH_INFO", reqbuf, 1);
}
setenv("SERVER_PORT", serverport, 1);
setenv("SERVER_SOFTWARE", "quark-"VERSION, 1);
setenv("SCRIPT_NAME", cgi_script, 1);
setenv("REMOTE_ADDR", host, 1);
setenv("REQUEST_URI", reqbuf, 1);
logmsg("CGI SERVER_NAME=%s SCRIPT_NAME=%s REQUEST_URI=%s\n",
reqhost, cgi_script, reqbuf);
if (chdir(cgi_dir) == -1)
logerrmsg("error\tchdir to cgi directory %s failed: %s\n",
cgi_dir, strerror(errno));
if ((cgi = popen(cgi_script, "r"))) {
status = 200;
if ((linelen = getline(&line, &linesiz, cgi)) > 0) {
if (strncmp(line, "Status:", strlen("Status:")) == 0) {
statusline = line + strlen("Status:") + 1;
errno = 0;
status = strtol(statusline, NULL, 10);
if(errno)
status = 200;
if (putresentry(HEADER, statusline, tstamp(0)))
return;
writedata(line, linelen);
} else {
if (putresentry(HEADER, statusline, tstamp(0)))
return;
}
}
while ((r = fread(resbuf, 1, MAXBUFLEN, cgi)) > 0) {
if (writedata(resbuf, r)) {
pclose(cgi);
return;
}
}
free(line);
pclose(cgi);
} else {
logerrmsg("error\t%s requests %s, but cannot run cgi script %s: %s\n",
host, reqbuf, cgi_script, strerror(errno));
if (putresentry(HEADER, HttpNotFound, tstamp(0))
|| putresentry(CONTENTTYPE, texthtml))
return;
status = 404;
if (req.type == GET)
writetext("\r\n<html><body>"HttpNotFound"</body></html>\r\n");
}
}
void
response(void) {
char *p;
struct stat st;
int r;
for (p = reqbuf; *p; p++) {
if (*p == '\\' || (*p == '/' && *(p + 1) == '.')) {
/* don't serve bogus or hidden files */
if (putresentry(HEADER, HttpForbidden, tstamp(0))
|| putresentry(CONTENTTYPE, texthtml))
return;
status = 403;
if (req.type == GET)
writetext("\r\n<html><body>"HttpForbidden"</body></html>\r\n");
return;
}
}
r = stat(reqbuf, &st);
if (cgi_mode) {
if(r != -1 && !S_ISDIR(st.st_mode))
responsefile();
else
responsecgi();
} else {
if (r != -1 && S_ISDIR(st.st_mode))
responsedir();
else
responsefile();
}
}
int
getreqentry(char *name, char *target, size_t targetlen, char *breakchars) {
char *p, *res;
if ((res = strstr(reqbuf, name))) {
for (res = res + strlen(name); *res && (*res == ' ' || *res == '\t'); ++res);
if (!*res)
return 1;
for (p = res; *p && !strchr(breakchars, *p); ++p);
if (!*p)
return 1;
if ((size_t)(p - res) >= targetlen)
return 1;
memcpy(target, res, p - res);
target[p - res] = 0;
return 0;
}
return -1;
}
int
request(void) {
char *p, *res;
ssize_t r;
size_t offset = 0;
/* read request into reqbuf (MAXBUFLEN byte of reqbuf is emergency 0 terminator */
for (; (r = read(req.fd, reqbuf + offset, MAXBUFLEN - offset)) > 0 && offset < MAXBUFLEN
&& !strstr(reqbuf, "\r\n\r\n") && !strstr(reqbuf, "\n\n"); )
{
offset += r;
reqbuf[offset] = 0;
}
if (r == -1) {
logerrmsg("error\tread: %s\n", strerror(errno));
return -1;
}
/* extract host and mod */
if (getreqentry("Host:", reqhost, LENGTH(reqhost), " \t\r\n") != 0)
goto invalid_request;
if (getreqentry("If-Modified-Since:", reqmod, LENGTH(reqmod), "\r\n") == 1)
goto invalid_request;
/* extract method */
for (p = reqbuf; *p && *p != '\r' && *p != '\n'; p++);
if (*p == '\r' || *p == '\n') {
*p = 0;
/* check command */
if (!strncmp(reqbuf, "GET ", 4) && reqbuf[4] == '/')
req.type = GET;
else if (!strncmp(reqbuf, "HEAD ", 5) && reqbuf[5] == '/')
req.type = HEAD;
else
goto invalid_request;
} else {
goto invalid_request;
}
/* determine path */
for (res = reqbuf + req.type; *res && *(res + 1) == '/'; res++); /* strip '/' */
if (!*res)
goto invalid_request;
for (p = res; *p && *p != ' ' && *p != '\t'; p++);
if (!*p)
goto invalid_request;
*p = 0;
memmove(reqbuf, res, (p - res) + 1);
return 0;
invalid_request:
return -1;
}
void
serve(int fd) {
int result;
socklen_t salen;
struct sockaddr sa;
while (running) {
salen = sizeof sa;
if ((req.fd = accept(fd, &sa, &salen)) == -1) {
/* el cheapo socket release */
logerrmsg("info\tcannot accept: %s, sleep a second...\n", strerror(errno));
sleep(1);
continue;
}
result = fork();
if (result == 0) {
close(fd);
/* get host */
host[0] = 0;
switch(sa.sa_family) {
case AF_INET:
inet_ntop(AF_INET, &(((struct sockaddr_in *)&sa)->sin_addr),
host, sizeof host);
break;
case AF_INET6:
inet_ntop(AF_INET6, &(((struct sockaddr_in6 *)&sa)->sin6_addr),
host, sizeof host);
break;
}
result = request();
shutdown(req.fd, SHUT_RD);
status = -1;
if (result == 0)
response();
logmsg("%d\t%s\t%s\n", status, host, reqbuf);
shutdown(req.fd, SHUT_WR);
close(req.fd);
exit(EXIT_SUCCESS);
} else if (result == -1) {
logerrmsg("error\tfork failed: %s\n", strerror(errno));
}
close(req.fd);
}
logmsg("info\tshutting down\n");
}
void
sighandler(int sig) {
if (sig == SIGCHLD) {
while(0 < waitpid(-1, NULL, WNOHANG));
} else {
logerrmsg("info\tsignal %s, closing down\n", strsignal(sig));
close(fd);
running = 0;
}
}
void
usage(void) {
fprintf(stderr, "usage: quark [-c] [-d cgidir] [-e cgiscript] [-g group] "
"[-i index] [-l] [-p port] [-r docroot] [-s server] "
"[-u user] [-v]\n");
exit(EXIT_FAILURE);
}
int
main(int argc, char *argv[]) {
struct addrinfo hints, *ai = NULL;
struct passwd *upwd = NULL;
struct group *gpwd = NULL;
int i;
ARGBEGIN {
case 'c':
cgi_mode = 1;
break;
case 'd':
cgi_dir = EARGF(usage());
break;
case 'e':
cgi_script = EARGF(usage());
break;
case 'u':
user = EARGF(usage());
break;
case 'g':
group = EARGF(usage());
break;
case 'i':
docindex = EARGF(usage());
break;
case 'l':
allowdirlist = 1;
break;
case 'r':
docroot = EARGF(usage());
break;
case 'p':
serverport = EARGF(usage());
break;
case 's':
servername = EARGF(usage());
break;
case 'v':
die("quark-"VERSION"\n");
default:
usage();
} ARGEND;
/* sanity checks */
if (user && *user && !(upwd = getpwnam(user)))
die("error\tinvalid user %s\n", user);
if (group && *group && !(gpwd = getgrnam(group)))
die("error\tinvalid group %s\n", group);
signal(SIGCHLD, sighandler);
signal(SIGHUP, sighandler);
signal(SIGINT, sighandler);
signal(SIGQUIT, sighandler);
signal(SIGABRT, sighandler);
signal(SIGTERM, sighandler);
signal(SIGPIPE, SIG_IGN);
/* init */
setbuf(stdout, NULL); /* unbuffered stdout */
memset(&hints, 0, sizeof hints);
hints.ai_family = AF_INET;
hints.ai_socktype = SOCK_STREAM;
hints.ai_flags = AI_PASSIVE;
if ((i = getaddrinfo(servername, serverport, &hints, &ai))) {
logerrmsg("error\tgetaddrinfo: %s\n", gai_strerror(i));
goto err;
}
if ((fd = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol)) == -1) {
logerrmsg("error\tsocket: %s\n", strerror(errno));
goto err;
}
if (bind(fd, ai->ai_addr, ai->ai_addrlen) == -1) {
logerrmsg("error\tbind: %s\n", strerror(errno));
goto err;
}
if (listen(fd, SOMAXCONN) == -1) {
logerrmsg("error\tlisten: %s\n", strerror(errno));
goto err;
}
if (!strcmp(serverport, "80"))
i = snprintf(location, sizeof location, "http://%s", servername);
else
i = snprintf(location, sizeof location, "http://%s:%s", servername, serverport);
if (i >= sizeof location) {
logerrmsg("error\tlocation too long\n");
goto err;
}
if (chdir(docroot) == -1) {
logerrmsg("error\tchdir %s: %s\n", docroot, strerror(errno));
goto err;
}
if (chroot(".") == -1) {
logerrmsg("error\tchroot .: %s\n", strerror(errno));
goto err;
}
if (gpwd && setgid(gpwd->gr_gid) == -1) {
logerrmsg("error\tcannot set group id\n");
goto err;
}
if (upwd && setuid(upwd->pw_uid) == -1) {
logerrmsg("error\tcannot set user id\n");
goto err;
}
if (getuid() == 0) {
logerrmsg("error\twon't run with root permissions, choose another user\n");
goto err;
}
if (getgid() == 0) {
logerrmsg("error\twon't run with root permissions, choose another group\n");
goto err;
}
logmsg("ready\t%s:%s\t%s\n", servername, serverport, docroot);
serve(fd); /* main loop */
close(fd);
freeaddrinfo(ai);
return EXIT_SUCCESS;
err:
if (fd != -1)
close(fd);
if (ai)
freeaddrinfo(ai);
return EXIT_FAILURE;
}