vger/main.c
2020-12-02 13:32:39 +01:00

201 lines
4.9 KiB
C

/*
* Copyright (c) 2020 Solène Rapenne <solene@openbsd.org>
*
* BSD 2-clause License
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/stat.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <err.h>
#include <errno.h>
#define BUFF_LEN_1 1000
#define BUFF_LEN_2 1025
#define BUFF_LEN_3 1024
#define GEMINI_PART 9
#define DEFAULT_CHROOT "/var/gemini/"
void ok_status(void);
void err_status(void);
void display_file(char *);
int main (int, char **);
void
ok_status(void)
{
printf("20 text/gemini; lang=en\r\n");
}
void
err_status(void)
{
printf("40 text/gemini; lang=en\r\n");
}
void
display_file(char *path)
{
size_t buflen = BUFF_LEN_1;
char *buffer[BUFF_LEN_1];
ssize_t nread;
struct stat sb;
/* this is to check if path is a directory */
stat(path, &sb);
FILE *fd = fopen(path, "r");
if (fd != NULL && S_ISDIR(sb.st_mode) != 1) {
/* check if directory */
ok_status();
/* read the file and write it to stdout */
while ((nread = fread(buffer, sizeof(char), buflen, fd)) != 0)
fwrite(buffer, sizeof(char), nread, stdout);
fclose(fd);
} else {
err_status();
/*
* fprintf(stderr, "can't open %s %ld: %s\n", path,strlen(path),
* strerror(errno));
*/
}
}
int
main(int argc, char **argv)
{
char buffer [BUFF_LEN_2];
char request [BUFF_LEN_2];
char hostname [BUFF_LEN_2];
char file [BUFF_LEN_2];
char path [BUFF_LEN_2] = "";
int option;
char *pos;
while ((option = getopt(argc, argv, ":d:")) != -1) {
switch (option) {
case 'd':
strlcpy(path, optarg, sizeof(path));
break;
}
}
if (strlen(path) == 0)
strlcpy(path, DEFAULT_CHROOT, sizeof(DEFAULT_CHROOT));
#ifdef __OpenBSD__
if (unveil(path, "r") == -1)
err(1, "unveil");
if (pledge("stdio rpath", NULL) == -1)
err(1, "pledge");
#endif
/*
* read 1024 chars from stdin
* to get the request
*/
fgets(request, BUFF_LEN_3, stdin);
/* remove \r\n at the end of string */
pos = strchr(request, '\r');
if (pos != NULL)
strlcpy(pos, "\0", 1);
/*
* check if the beginning of the request starts with
* gemini://
*/
int start_with_gemini = strncmp(request, "gemini://", 9);
/* the request must start with gemini:// */
if (start_with_gemini != 0) {
/* error code url malformed */
printf("request «%s» doesn't match gemini:// at index %i",
request, start_with_gemini);
exit(1);
}
/* remove the gemini:// part */
strlcpy(buffer, request + GEMINI_PART, sizeof(buffer) - GEMINI_PART);
strlcpy(request, buffer, sizeof(request));
/*
* look for the first / after the hostname
* in order to split hostname and uri
*/
pos = strchr(request, '/');
if (pos != NULL) {
/* if there is a / found */
int position = -1;
for (int i = 0; i < sizeof(request); i++) {
if (*pos == request[i]) {
position = i;
break;
}
}
/* separate hostname and uri */
if (position != -1) {
strlcpy(hostname, request, position);
strlcpy(file, request + position + 1, sizeof(request));
/*
* use a default file if no file are requested this
* can happen in two cases gemini://hostname/
* gemini://hostname/directory/
*/
if (strlen(file) == 0)
strlcpy(file, "/index.gmi", 11);
if (file[strlen(file) - 1] == '/')
strlcat(file, "index.gmi", sizeof(file));
} else {
puts("error undefined");
exit(2);
}
} else {
/*
* there are no slash / in the request
* -2 to remove \r\n
*/
strlcpy(hostname, request, sizeof(hostname));
strlcpy(file, "/index.gmi", 11);
}
/* add the base dir to the file requested */
strlcat(path, file, sizeof(path));
/* open file and send it to stdout */
display_file(path);
return (0);
}