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| -rw-r--r-- | .gitignore | 2 | ||||
| -rw-r--r-- | LICENSE | 674 | ||||
| -rw-r--r-- | Makefile | 33 | ||||
| -rw-r--r-- | dpi.c | 72 | ||||
| -rw-r--r-- | dpi.h | 7 | ||||
| -rw-r--r-- | gopher.filter.dpi.c | 469 | ||||
| -rw-r--r-- | io.c | 106 | ||||
| -rw-r--r-- | io.h | 9 |
8 files changed, 1372 insertions, 0 deletions
diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000..ce5da85 --- /dev/null +++ b/.gitignore @@ -0,0 +1,2 @@ +*.o +gopher.filter.dpi @@ -0,0 +1,674 @@ + GNU GENERAL PUBLIC LICENSE + Version 3, 29 June 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/> + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The GNU General Public License is a free, copyleft license for +software and other kinds of works. + + The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. By contrast, +the GNU General Public License is intended to guarantee your freedom to +share and change all versions of a program--to make sure it remains free +software for all its users. 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If not, see <http://www.gnu.org/licenses/>. + +Also add information on how to contact you by electronic and paper mail. + + If the program does terminal interaction, make it output a short +notice like this when it starts in an interactive mode: + + <program> Copyright (C) <year> <name of author> + This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. + This is free software, and you are welcome to redistribute it + under certain conditions; type `show c' for details. + +The hypothetical commands `show w' and `show c' should show the appropriate +parts of the General Public License. Of course, your program's commands +might be different; for a GUI interface, you would use an "about box". + + You should also get your employer (if you work as a programmer) or school, +if any, to sign a "copyright disclaimer" for the program, if necessary. +For more information on this, and how to apply and follow the GNU GPL, see +<http://www.gnu.org/licenses/>. + + The GNU General Public License does not permit incorporating your program +into proprietary programs. If your program is a subroutine library, you +may consider it more useful to permit linking proprietary applications with +the library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. But first, please read +<http://www.gnu.org/philosophy/why-not-lgpl.html>. diff --git a/Makefile b/Makefile new file mode 100644 index 0000000..b83474a --- /dev/null +++ b/Makefile @@ -0,0 +1,33 @@ +NAME = gopher +BIN = gopher.filter.dpi +OBJ = gopher.filter.dpi.o io.o dpi.o +DILLO_DIR = ~/.dillo +DPI_DIR = $(DILLO_DIR)/dpi +DPIDRC = $(DILLO_DIR)/dpidrc + +all: $(BIN) + +$(BIN): $(OBJ) + +$(DPIDRC): + cp /etc/dillo/dpidrc $@ + +install-proto: $(DPIDRC) + echo 'proto.gopher=gopher/gopher.filter.dpi' >> $< + +install: $(BIN) install-proto + mkdir -p $(DPI_DIR)/$(NAME) + cp -f $(BIN) $(DPI_DIR)/$(NAME) + +link: $(BIN) install-proto + mkdir -p $(DPI_DIR)/$(NAME) + ln -frs $(BIN) $(DPI_DIR)/$(NAME) + +uninstall: $(BIN) + rm -f $(DPI_DIR)/$(NAME)/$(BIN) + +clean: + rm $(BIN) $(OBJ) + +.PHONY: + all install uninstall clean @@ -0,0 +1,72 @@ +#include <unistd.h> +#include <stdlib.h> +#include <string.h> +#include <errno.h> +#include <err.h> +#include "dpi.h" +#include "io.h" + +static void check_auth() { + char buf[30]; + int rc; + char key[4], local_key[4]; + char keys[128]; + char *home; + ssize_t sz; + rc = read_all(STDIN_FILENO, buf, 29); + if (rc < 0) err(1, "read auth"); + buf[30] = '\0'; + rc = sscanf(buf, "<cmd='auth' msg='%4x' '>", key); + if (rc < 0) err(1, "auth: %.*s", 29, buf); + if (rc < 1) errx(1, "auth: %.*s", 29, buf); + home = getenv("HOME"); + if (!home) home = "."; + sz = read_file(keys, sizeof(keys), "%s/.dillo/dpid_comm_keys", home); + if (sz < 0) err(1, "read dillo comm keys"); + rc = sscanf(keys, "%*d %4x' '>", local_key); + if (rc < 0) err(1, "comm key: %.*s", sz, keys); + if (rc < 1) errx(1, "comm key: %.*s", sz, keys); + if (memcmp(key, local_key, 4)) errx(1, "wrong dillo key"); +} + +static void get_url(char *url_buf, size_t url_len) { + char buf[21]; + size_t len; + int rc; + int i; + + rc = read_all(STDIN_FILENO, buf, sizeof(buf)); + if (rc < 0) err(1, "read open_url"); + if (strncmp(buf, "<cmd='open_url' url='", 21)) { + err(1, "bad open_url cmd: %.*s", sizeof(buf), buf); + } + len = url_len; + rc = read_some(STDIN_FILENO, url_buf, &len); + if (rc < 0) err(1, "read url"); + + for (i = 0; i < len-1; i++) { + if (url_buf[i] == '\'' && url_buf[i+1] == ' ') break; + } + if (i > len-3 || strncmp(url_buf + i, "' '>", 4)) { + err(1, "bad url end: %.*s", len, url_buf); + } + url_buf[i] = '\0'; +} + +void dpi_read_request(char *url_buf, size_t url_len) { + check_auth(); + get_url(url_buf, url_len); +} + +void dpi_send_status(const char *status) { + int rc = printf("<cmd='send_status_msg' msg='%s' '>", status); + if (rc < 0) err(1, "send_status_msg"); +} + +void dpi_send_header(const char *url, const char *content_type) { + int rc; + if (!url) url = ""; + rc = printf("<cmd='start_send_page' url='%s' '>" + "Content-Type: %s\n\n", url, content_type); + if (rc < 0) err(1, "start_send_page"); +} @@ -0,0 +1,7 @@ +#pragma once + +#include <stddef.h> + +void dpi_read_request(char *url_buf, size_t url_len); +void dpi_send_status(const char *status); +void dpi_send_header(const char *url, const char *content_type); diff --git a/gopher.filter.dpi.c b/gopher.filter.dpi.c new file mode 100644 index 0000000..5e40b2a --- /dev/null +++ b/gopher.filter.dpi.c @@ -0,0 +1,469 @@ +#include <err.h> +#include <errno.h> +#include <stdarg.h> +#include <stdio.h> +#include <string.h> +#include <fcntl.h> +#include <sys/types.h> + +#include "dpi.h" +#include "io.h" + +static void respond_errstr(const char *errstr, const char *fmt, ...) { + va_list ap; + int err = errno; + va_start(ap, fmt); + dpi_send_header(NULL, "text/plain"); + vprintf(fmt, ap); + printf(": %s", errstr ? errstr : strerror(err)); + va_end(ap); +} + +static void respond_err(const char *fmt, ...) { + va_list ap; + int err = errno; + va_start(ap, fmt); + dpi_send_header(NULL, "text/plain"); + vprintf(fmt, ap); + printf(": %s", strerror(err)); + va_end(ap); +} + +static void respond_errx(const char *fmt, ...) { + va_list ap; + int err = errno; + va_start(ap, fmt); + dpi_send_header(NULL, "text/plain"); + vprintf(fmt, ap); + va_end(ap); +} + +static int parse_type_path(const char *url, char *type, char *path, size_t path_len) { + if (!*url) { + *path = '\0'; + *type = '\0'; + return 0; + } + *type = *url++; + while (path_len > 0 && *url != '\0') { + *path++ = *url++; + path_len--; + } + if (path_len <= 0) { + errno = EMSGSIZE; + return -1; + } + *path = '\0'; + return 0; +} + +static int parse_port_type_path(const char *url, char *port, size_t port_len, char *type, char *path, size_t path_len) { + while (port_len > 0 && *url != '\0' && *url != '/') { + *port++ = *url++; + port_len--; + } + if (port_len <= 0) { + errno = EMSGSIZE; + return -1; + } + *port = '\0'; + if (*url == '/') return parse_type_path(url + 1, type, path, path_len); + *path = '\0'; + *type = '\0'; + return 0; +} + +static int parse_url(const char *url, char *host, size_t host_len, char *port, size_t port_len, char *type, char *path, size_t path_len) { + if (!strncmp(url, "gopher:", 7)) url += 7; + if (!strncmp(url, "//", 2)) url += 2; + + while (host_len > 0 && *url != '\0' && *url != '/' && *url != ':') { + *host++ = *url++; + host_len--; + } + if (host_len <= 0) { + errno = EMSGSIZE; + return -1; + } + *host = '\0'; + if (*url == ':') return parse_port_type_path(url + 1, port, port_len, type, path, path_len); + *port = '\0'; + if (*url == '/') return parse_type_path(url + 1, type, path, path_len); + *path = '\0'; + return 0; +} + +static void parse_line(char *line, char *type, char **title, char **selector, char **host, char **port) { + *type = *line; + if (!*line) { + *title = *selector = *host = *port = NULL; + return; + } + + *title = ++line; + while (*line && *line != '\t') line++; + if (!*line) { + *selector = *host = *port = NULL; + return; + } + *line++ = '\0'; + + *selector = line; + while (*line && *line != '\t') line++; + if (!*line) { + *host = *port = NULL; + return; + } + *line++ = '\0'; + + *host = line; + while (*line && *line != '\t') line++; + if (!*line) { + *port = NULL; + return; + } + *line++ = '\0'; + + *port = line; + while (*line && *line >= '0' && *line <= '9') line++; + *line = '\0'; +} + +static int putchar_htmlenc(char c) { + switch (c) { + case '<': return printf("<"); + case '>': return printf(">"); + case '"': return printf("""); + default: return putchar(c); + } +} + +static void print_htmlenc(const char *str) { + char c; + while ((c = *str++)) putchar_htmlenc(c); +} + +static void render_line_info(const char *title) { + printf("<tr><td></td><td><pre>"); + print_htmlenc(title); + printf("</pre></td></tr>\n"); +} + +static void render_line_unknown(char type, const char *line) { + printf("<tr><td>"); + putchar_htmlenc(type); + printf("</td><td><pre>"); + print_htmlenc(line + 1); + printf("</pre></td></tr>\n"); +} + +static void render_line_empty() { + printf("<tr><td colspan=2></td></tr>\n"); +} + +static void render_line_line() { + printf("<tr><td colspan=2><hr></td></tr>\n"); +} + +static const char *icon(char type) { + switch (type) { + case '0': // text + return "<img src=\"data:image/gif;base64,R0lGODdhFAAXAPAAMf///wAAACwAAAAAFAAXAAACOYSPqcvtD02YtFYV4Ez55S5J1gZ0INicoWixVBmNpry80WG7JLfftozC9WK9UW2oIQGPwSTw+YI+CwA7\">"; + case '1': // menu + return "<img src=\"data:image/gif;base64,R0lGODdhFAAXAPAAMf///wAAACwAAAAAFAAXAAACOYSPqcvtD1OYNAZ1XcZtL1oZHpSNJGBqoYVO0QG+aJt263mTuUbL9AWcBYctoZEIdP1AzBisCc0UAAA7\">"; + case '7': // search + return "<img src=\"data:image/gif;base64,R0lGODdhFAAXAPAAMf///wAAACwAAAAAFAAXAAACQoSPqcvtD02YtNoKQkRUWT8l2hFypSSNZ7ZqoWqOJJzFjCqzOZmKK8oC7Wq/1FC36AiTRdxShPQdldLN7ILF6rLZAgA7\">"; + case '5': + case '9': // binary + return "<img src=\"data:image/gif;base64,R0lGODdhFAAXAPAAMf///wAAACwAAAAAFAAXAAACRoSPqcvtD02YtFYV4Ez55S4dlNSVIglsW3qy6QeTVxmvr4WqIDLKKGaL3H49IO2FNOZiSqRu0XsGRavqlLqLWLbcWfcbKAAAOw==\">"; + case '8': // telnet + return "<img src=\"data:image/gif;base64,R0lGODlhFAAXAPAAAP///wAAACH5BAAAAAAALAAAAAAUABcAAAJBhI+py+0PT5i0WmpClLrjr3GAN41lKYboGmad63rICZtyWrPza8a2ymORgKMN7IK8xJJI46L1aDGZv6nS2sxsQgUAOw==\">"; + case 'g': + case 'I': // image + return "<img src=\"data:image/gif;base64,R0lGODdhFAAXAPAAMf///wAAACwAAAAAFAAXAAACQISPqcvtD02YtFYV4EzZZtSBgMdJR2eV5jimJolebXzBsrRhJP6BXk6J+HqnW5E4M844uyPT5XzmhsLj71rDYgsAOw==\">"; + case 's': // audio + return "<img src=\"data:image/gif;base64,R0lGODlhFAAXAPAAAP///wAAACH5BAAAAAAALAAAAAAUABcAAAJIhI+py+0PTZi02gpCRDRqOS1fJoHjEaJlx5GuBoeYS8KZnNj6bbd73FP9eLzPEFgM/lKolLHGbLagJ1XpFW2MWJvk5YsBiycFADs=\">"; + case 'h': // web + return "<img src=\"data:image/gif;base64,R0lGODdhFAAXAPAAMf///wAAACwAAAAAFAAXAAACQISPqcvtD02YtFYV4Ey5g8x9iOeFovRd5gmWnHWO22HNo0Nh4JKvvE0DynY/Yo/RChJ1RqFpdywOI8OatZa6agsAOw==\">"; + default: + return ""; + } +} + +static void render_line_link(char type, const char *title, const char *selector, const char *host, const char *port) { + size_t indent = 0; + while (*title == ' ') { + title++; + indent++; + } + printf("<tr><td>%s</td><td><pre>%*s<a href=\"gopher://", icon(type), indent, ""); + if (host) { + print_htmlenc(host); + } + if (port && strcmp(port, "70")) { + putchar(':'); + print_htmlenc(port); + } + if (type) { + putchar('/'); + putchar_htmlenc(type); + putchar('/'); + } + if (selector) { + if (*selector == '/') selector++; + print_htmlenc(selector); + } + printf("\">"); + if (title) { + print_htmlenc(title); + } + printf("</a></pre></td></tr>\n"); +} + +static void render_line_search(char type, const char *title, const char *selector, const char *host, const char *port) { + size_t indent = 0; + while (*title == ' ') { + title++; + indent++; + } + printf("<tr><td>%s</td><td><form method=\"get\" action=\"gopher://", icon(type)); + if (host) { + print_htmlenc(host); + } + if (port && strcmp(port, "70")) { + putchar(':'); + print_htmlenc(port); + } + if (type) { + putchar('/'); + putchar_htmlenc(type); + putchar('/'); + } + if (selector) { + if (*selector == '/') selector++; + print_htmlenc(selector); + } + printf("\"><pre>%*s", indent, ""); + printf("\n%*s<input name=__gopher__query__ size=72 placeholder=\"", indent, ""); + if (title) { + print_htmlenc(title); + } + printf("\"></pre></form></td></tr>\n"); +} + +static void render_line_telnet(char type, const char *title, const char *host, const char *port) { + size_t indent = 0; + while (*title == ' ') { + title++; + indent++; + } + printf("<tr><td>%s</td><td><pre>%*s<a href=\"telnet://", icon(type), indent, ""); + if (host) { + print_htmlenc(host); + } + if (port && strcmp(port, "23")) { + putchar(':'); + print_htmlenc(port); + } + printf("\">"); + if (title) { + print_htmlenc(title); + } + printf("</a></pre></td></tr>\n"); +} + +static void render_line_href(char type, const char *title, const char *selector) { + size_t indent = 0; + while (*title == ' ') { + title++; + indent++; + } + printf("<tr><td>%s</td><td><pre>%*s<a href=\"", icon(type), indent, ""); + print_htmlenc(selector); + printf("\">"); + print_htmlenc(title); + printf("</a></pre></td></tr>\n"); +} + +static void render_line(char *line, size_t len) { + char type, *title, *selector, *host, *port; + if (len < 1) return; + line[len] = '\0'; + printf("<!--"); + print_htmlenc(line); + printf("-->\n"); + parse_line(line, &type, &title, &selector, &host, &port); + switch (type) { + case '0': + case '1': + case '5': + case '9': + case 'I': + case 'g': + case 's': + return render_line_link(type, title, selector, host, port); + case '7': + return render_line_search(type, title, selector, host, port); + case '8': + return render_line_telnet(type, title, host, port); + case 'h': + if (*selector == '/') selector++; + if (!strncmp(selector, "URL:", 4)) selector += 4; + return render_line_href(type, title, selector); + case 'i': + case '3': + return render_line_info(title); + case 'E': + return render_line_info(line); + case '.': + return render_line_empty(); + case '_': + return render_line_line(); + default: + return render_line_unknown(type, line); + } +} + +static void compact_buf(char *buf, size_t start, size_t end) { + size_t i; + for (i = start; i < end; i++) { + buf[i - start] = buf[i]; + } +} + +static size_t read_line(char *buf, size_t len) { + size_t i; + for (i = 0; i < len && buf[i] != '\r' && buf[i] != '\n'; i++); + if (buf[i] == '\r' || buf[i] == '\n') { + if (i+1 < len && buf[i+1] == '\n') i++; + render_line(buf, i); + return i+1; + } + return 0; +} + +static void read_response(int s) { + char buf[4096]; + size_t len; + size_t start = 0; + size_t end = 0; + int rc; + + while (1) { + /* fill up the buffer */ + len = sizeof(buf) - end; + rc = read_some(s, buf + end, &len); + if (rc < 0 && errno == EPIPE) break; + if (rc < 0) return warn("read_some"); + end += len; + /* read full lines */ + while ((len = read_line(buf + start, end - start))) start += len; + compact_buf(buf, start, end); + end -= start; + start = 0; + } + /* read the partial line */ + if (start < end) render_line(buf + start, end - start); + +} + +static void read_data(int s) { + char buf[4096]; + size_t len = sizeof(buf); + int rc; + while (1) { + rc = read_some(s, buf, &len); + if (rc < 0 && errno == EPIPE) return; + if (rc < 0) return warn("read response"); + rc = write_all(0, buf, len); + if (rc < 0) return warn("write response"); + } +} + +static void render_dir(int s, const char *url) { + dpi_send_header(url, "text/html"); + printf("<doctype html>"); + printf("<html><head><title>"); + print_htmlenc(url); + printf("</title></head><body><table>"); + read_response(s); + printf("</table></body></html>"); +} + +static void render_text(int s, const char *url) { + dpi_send_header(url, "text/plain"); + read_data(s); +} + +static void render_binary(int s, const char *url) { + // dpi_send_header(url, "application/octet-stream"); + dpi_send_header(url, "text/plain"); + read_data(s); +} + +static const char *detect_image_content_type(const char buf[4]) { + if (!strncmp(buf, "GIF8", 4)) return "image/gif"; + if (!strncmp(buf, "\x89PNG", 4)) return "image/png"; + if (!strncmp(buf, "\xff\xd8", 2)) return "image/jpeg"; + return "text/plain"; +} + +static void render_image(int s, const char *url) { + int rc; + char buf[4]; + rc = read_all(s, buf, sizeof(buf)); + if (rc < 0) return respond_err("read image"); + dpi_send_header(url, detect_image_content_type(buf)); + rc = write_all(0, buf, 4); + if (rc < 0) return warn("write image"); + read_data(s); +} + +static void fix_path(char *path) { + char *start, *end; + /* change form input name to query */ + start = strstr(path, "__gopher__query__="); + if (!start) return; + end = start + 18; + do *start++ = *end++; + while (*end); + if (start[-1] == '?') start--; + *start = '\0'; +} + +static void respond(const char *url) { + int rc; + const char *errstr = NULL; + char host[1024]; + char port[1024]; + char type; + char path[4096]; + int s; + rc = parse_url(url, host, sizeof(host), port, sizeof(port), &type, path, sizeof(path)); + if (rc < 0) return respond_err("parse_url"); + if (!*host) strcpy(host, "127.0.0.1"); + if (!*port) strcpy(port, "70"); + if (!type) type = '1'; + if (*path) fix_path(path); + s = tcp_connect(host, port, &errstr); + if (s < 0) return respond_errstr(errstr, "tcp_connect"); + rc = write_all(s, path, strlen(path)); + if (rc < 0) return respond_err("write request"); + rc = write_all(s, "\r\n", 2); + if (rc < 0) return respond_err("write request end"); + switch (type) { + case '1': return render_dir(s, url); + case '7': return render_dir(s, url); + case 'g': + case 'I': return render_image(s, url); + case '9': return render_binary(s, url); + default: return render_text(s, url); + } +} + +int main() { + char url[1024]; + setvbuf(stdout, NULL, _IONBF, BUFSIZ); + dpi_read_request(url, sizeof(url)); + respond(url); +} @@ -0,0 +1,106 @@ +#include <string.h> +#include <errno.h> +#include <unistd.h> +#include <stdarg.h> +#include <sys/stat.h> +#include <stdio.h> +#include <fcntl.h> +#include <netdb.h> +#include <netinet/in.h> + +#include "io.h" + +int read_all(int fd, unsigned char *buf, size_t len) { + ssize_t nbytes; + while (len > 0) { + nbytes = read(fd, buf, len); + if (nbytes == 0) { errno = EPIPE; return -1; } + if (nbytes < 0 && errno == EINTR) continue; + if (nbytes < 0) return -1; + buf += nbytes; + len -= nbytes; + } + return 0; +} + +int read_some(int fd, unsigned char *buf, size_t *lenp) { + ssize_t nbytes; + do nbytes = read(fd, buf, *lenp); + while (nbytes < 0 && errno == EINTR); + if (nbytes == 0) { errno = EPIPE; return -1; } + if (nbytes < 0) return -1; + *lenp = nbytes; + return 0; +} + +int write_all(int fd, const unsigned char *buf, size_t count) { + ssize_t nbytes; + while (count > 0) { + nbytes = write(fd, buf, count); + if (nbytes < 0 && errno == EINTR) continue; + if (nbytes < 0) return -1; + buf += nbytes; + count -= nbytes; + } + return 0; +} + +ssize_t read_file(char *buf, size_t len, const char *fmt, ...) { + va_list ap; + int rc; + struct stat st; + int fd; + + va_start(ap, fmt); + rc = vsnprintf(buf, len, fmt, ap); + va_end(ap); + if (rc < 0) return -1; + if ((size_t)rc >= len) { errno = ENAMETOOLONG; return -1; } + + rc = stat(buf, &st); + if (rc < 0) return -1; + if ((size_t)st.st_size > len-1) { errno = EMSGSIZE; return -1; } + + fd = open(buf, O_RDONLY); + if (fd < 0) return -1; + + rc = read_all(fd, buf, st.st_size); + if (rc < 0) return -1; + + buf[(size_t)st.st_size] = '\0'; + + close(fd); + return st.st_size; +} + +int tcp_connect(const char *host, const char *port, const char **errp) { + struct addrinfo hints; + struct addrinfo *result, *rp; + int s; + int fd; + int err; + + memset(&hints, 0, sizeof(hints)); + hints.ai_family = AF_UNSPEC; + hints.ai_protocol = IPPROTO_TCP; + + if (host && host[0] == '\0') host = NULL; + s = getaddrinfo(host, port, &hints, &result); + if (s < 0) { + *errp = gai_strerror(s); + return -1; + } + + for (rp = result; rp; rp = rp->ai_next) { + fd = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol); + if (fd < 0) continue; + if (connect(fd, rp->ai_addr, rp->ai_addrlen) == 0) break; + err = errno; + close(fd); + errno = err; + } + if (rp == NULL) fd = -1; + + freeaddrinfo(result); + return fd; +} @@ -0,0 +1,9 @@ +#pragma once + +#include <stdio.h> + +int read_all(int fd, unsigned char *buf, size_t count); +int read_some(int fd, unsigned char *buf, size_t *lenp); +int write_all(int fd, unsigned const char *buf, size_t count); +ssize_t read_file(char *buf, size_t len, const char *fmt, ...); +int tcp_connect(const char *host, const char *port, char const **err); |