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Diffstat (limited to '')
| -rw-r--r-- | irc.c | 250 |
1 files changed, 250 insertions, 0 deletions
diff --git a/irc.c b/irc.c new file mode 100644 index 0000000..05f8f9d --- /dev/null +++ b/irc.c @@ -0,0 +1,250 @@ +/* Copyright (C) 2020 C. McEnroe <june@causal.agency> + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <https://www.gnu.org/licenses/>. + */ + +#include <assert.h> +#include <err.h> +#include <netdb.h> +#include <netinet/in.h> +#include <stdarg.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/socket.h> +#include <sys/stat.h> +#include <sysexits.h> +#include <tls.h> +#include <unistd.h> + +#include "chat.h" + +struct tls *client; + +static byte *readFile(size_t *len, FILE *file) { + struct stat stat; + int error = fstat(fileno(file), &stat); + if (error) err(EX_IOERR, "fstat"); + + byte *buf = malloc(stat.st_size); + if (!buf) err(EX_OSERR, "malloc"); + + rewind(file); + *len = fread(buf, 1, stat.st_size, file); + if (ferror(file)) err(EX_IOERR, "fread"); + + return buf; +} + +void ircConfig(bool insecure, FILE *cert, FILE *priv) { + struct tls_config *config = tls_config_new(); + if (!config) errx(EX_SOFTWARE, "tls_config_new"); + + int error = tls_config_set_ciphers(config, "compat"); + if (error) { + errx( + EX_SOFTWARE, "tls_config_set_ciphers: %s", + tls_config_error(config) + ); + } + + if (insecure) { + tls_config_insecure_noverifycert(config); + tls_config_insecure_noverifyname(config); + } + + if (cert) { + size_t len; + byte *buf = readFile(&len, cert); + error = tls_config_set_cert_mem(config, buf, len); + if (error) { + errx( + EX_CONFIG, "tls_config_set_cert_mem: %s", + tls_config_error(config) + ); + } + if (priv) { + free(buf); + buf = readFile(&len, priv); + } + error = tls_config_set_key_mem(config, buf, len); + if (error) { + errx( + EX_CONFIG, "tls_config_set_key_mem: %s", + tls_config_error(config) + ); + } + explicit_bzero(buf, len); + free(buf); + } + + client = tls_client(); + if (!client) errx(EX_SOFTWARE, "tls_client"); + + error = tls_configure(client, config); + if (error) errx(EX_SOFTWARE, "tls_configure: %s", tls_error(client)); + tls_config_free(config); +} + +int ircConnect(const char *host, const char *port) { + assert(client); + + struct addrinfo *head; + struct addrinfo hints = { + .ai_family = AF_UNSPEC, + .ai_socktype = SOCK_STREAM, + .ai_protocol = IPPROTO_TCP, + }; + int error = getaddrinfo(host, port, &hints, &head); + if (error) errx(EX_NOHOST, "%s:%s: %s", host, port, gai_strerror(error)); + + int sock = -1; + for (struct addrinfo *ai = head; ai; ai = ai->ai_next) { + sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); + if (sock < 0) err(EX_OSERR, "socket"); + + error = connect(sock, ai->ai_addr, ai->ai_addrlen); + if (!error) break; + + close(sock); + sock = -1; + } + if (sock < 0) err(EX_UNAVAILABLE, "%s:%s", host, port); + freeaddrinfo(head); + + error = tls_connect_socket(client, sock, host); + if (error) errx(EX_PROTOCOL, "tls_connect: %s", tls_error(client)); + + error = tls_handshake(client); + if (error) errx(EX_PROTOCOL, "tls_handshake: %s", tls_error(client)); + + return sock; +} + +static void debug(char dir, const char *line) { + if (!self.debug) return; + size_t len = strcspn(line, "\r\n"); + uiFormat( + Debug, Cold, NULL, "\3%d%c%c\3\t%.*s", + Gray, dir, dir, (int)len, line + ); + if (!isatty(STDERR_FILENO)) { + fprintf(stderr, "%c%c %.*s\n", dir, dir, (int)len, line); + } +} + +void ircSend(const char *ptr, size_t len) { + assert(client); + while (len) { + ssize_t ret = tls_write(client, ptr, len); + if (ret == TLS_WANT_POLLIN || ret == TLS_WANT_POLLOUT) continue; + if (ret < 0) errx(EX_IOERR, "tls_write: %s", tls_error(client)); + ptr += ret; + len -= ret; + } +} + +void ircFormat(const char *format, ...) { + char buf[1024]; + va_list ap; + va_start(ap, format); + int len = vsnprintf(buf, sizeof(buf), format, ap); + va_end(ap); + assert((size_t)len < sizeof(buf)); + debug('<', buf); + ircSend(buf, len); +} + +static const char *TagNames[TagCap] = { +#define X(name, id) [id] = name, + ENUM_TAG +#undef X +}; + +static void unescape(char *tag) { + for (;;) { + tag = strchr(tag, '\\'); + if (!tag) break; + switch (tag[1]) { + break; case ':': tag[1] = ';'; + break; case 's': tag[1] = ' '; + break; case 'r': tag[1] = '\r'; + break; case 'n': tag[1] = '\n'; + } + memmove(tag, &tag[1], strlen(&tag[1]) + 1); + if (tag[0]) tag = &tag[1]; + } +} + +static struct Message parse(char *line) { + struct Message msg = { .cmd = NULL }; + + if (line[0] == '@') { + char *tags = 1 + strsep(&line, " "); + while (tags) { + char *tag = strsep(&tags, ";"); + char *key = strsep(&tag, "="); + for (size_t i = 0; i < TagCap; ++i) { + if (strcmp(key, TagNames[i])) continue; + unescape(tag); + msg.tags[i] = tag; + break; + } + } + } + + if (line[0] == ':') { + char *origin = 1 + strsep(&line, " "); + msg.nick = strsep(&origin, "!"); + msg.user = strsep(&origin, "@"); + msg.host = origin; + } + + msg.cmd = strsep(&line, " "); + for (size_t i = 0; line && i < ParamCap; ++i) { + if (line[0] == ':') { + msg.params[i] = &line[1]; + break; + } + msg.params[i] = strsep(&line, " "); + } + + return msg; +} + +void ircRecv(void) { + static char buf[8191 + 512]; + static size_t len = 0; + + assert(client); + ssize_t ret = tls_read(client, &buf[len], sizeof(buf) - len); + if (ret == TLS_WANT_POLLIN || ret == TLS_WANT_POLLOUT) return; + if (ret < 0) errx(EX_IOERR, "tls_read: %s", tls_error(client)); + if (!ret) errx(EX_PROTOCOL, "server closed connection"); + len += ret; + + char *crlf; + char *line = buf; + for (;;) { + crlf = memmem(line, &buf[len] - line, "\r\n", 2); + if (!crlf) break; + *crlf = '\0'; + debug('>', line); + handle(parse(line)); + line = crlf + 2; + } + + len -= line - buf; + memmove(buf, line, len); +} |