From 985ba08eccf5127729d7b0904cca31ed3ffd575a Mon Sep 17 00:00:00 2001
From: phoebos <ben@bvnf.space>
Date: Thu, 6 Jan 2022 22:00:42 +0000
Subject: [PATCH] add basic gemini support

note: does not verify certificates at all
---
 hurl.c | 157 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 157 insertions(+)

diff --git a/hurl.c b/hurl.c
index 5641198..92cf2b0 100644
--- a/hurl.c
+++ b/hurl.c
@@ -692,6 +692,149 @@ err:
 	return ret;
 }
 
+
+int
+gemini_request(void)
+{
+	struct tls *t;
+	char buf[READ_BUF_SIZ], *p;
+	const char *errstr, *path;
+	size_t len = 0;
+	ssize_t r;
+	int fd = -1, ret = 1, geminiok = 0;
+
+	if (pledge("stdio dns inet rpath unveil", NULL) == -1)
+		err(1, "pledge");
+
+	if (!(t = tls_client())) {
+		errstr = tls_error(t);
+		fprintf(stderr, "tls_client: %s\n", errstr ? errstr : "");
+		goto err;
+	}
+	if (tls_configure(t, tls_config)) {
+		errstr = tls_error(t);
+		fprintf(stderr, "tls_configure: %s\n", errstr ? errstr : "");
+		goto err;
+	}
+	tls_config_insecure_noverifycert(tls_config);
+	tls_config_insecure_noverifyname(tls_config);
+
+	fd = edial(u.host, u.port);
+	if (tls_connect_socket(t, fd, u.host) == -1)
+		errx(1, "tls_connect: %s", tls_error(t));
+
+	if (pledge("stdio", NULL) == -1)
+		err(1, "pledge");
+
+	r = snprintf(buf, sizeof(buf), "%s%s%s%s%s\r\n",
+		u.proto,
+		u.host,
+		u.path[0] ? u.path : "/",
+		u.query[0] ? "?" : "", u.query);
+
+	if (r < 0 || (size_t)r >= sizeof(buf)) {
+		fprintf(stderr, "not writing header because it is truncated");
+		goto err;
+	}
+
+	for (len = r, p = buf; len > 0; ) {
+		r = tls_write(t, p, len);
+		if (r == TLS_WANT_POLLIN || r == TLS_WANT_POLLOUT) {
+			continue;
+		} else if (r == -1) {
+			fprintf(stderr, "tls_write: %s\n", tls_error(t));
+			goto err;
+		}
+		p += r;
+		len -= r;
+	}
+
+	for (len = 0; len < sizeof(buf);) {
+		/* NOTE: buffer size is -1 to NUL terminate the buffer for a
+				 string comparison. */
+		r = tls_read(t, &buf[len], sizeof(buf) - len - 1);
+		if (r == TLS_WANT_POLLIN || r == TLS_WANT_POLLOUT) {
+			continue;
+		} else if (r == 0) {
+			break;
+		} else if (r == -1) {
+			errstr = tls_error(t);
+			fprintf(stderr, "tls_read: %s\n", errstr ? errstr : "");
+			goto err;
+		}
+		len += r;
+	}
+	buf[len] = '\0';
+
+	if (!strncmp(buf, "20", sizeof("20") - 1))
+		geminiok = 1;
+
+	if (!(p = strstr(buf, "\r\n"))) {
+		fprintf(stderr, "no gemini header found or header too big\n");
+		goto err;
+	}
+	*p = '\0'; /* NUL terminate header part */
+	//cs = parse_content_length(buf, &expectedlen);
+	p += strlen("\r\n");
+	//bodylen = len - (p - buf); /* (partial) body after header */
+
+	if (geminiok) {
+		int n = len - (p - buf);
+		r = fwrite(p, 1, n, stdout);
+		if (ferror(stdout)) {
+			fprintf(stderr, "fwrite: stdout: %s\n", strerror(errno));
+			goto err;
+		}
+	} else {
+		/* if not 20 print header */
+		fputs(buf, stderr);
+		fputs("\r\n", stderr);
+		/* NOTE: we are nice and keep reading (not closing) until the server is done. */
+	}
+
+	while (1) {
+		r = tls_read(t, &buf, sizeof(buf));
+		if (r == TLS_WANT_POLLIN || r == TLS_WANT_POLLOUT) {
+			continue;
+		} else if (r == 0) {
+			break;
+		} else if (r == -1) {
+			errstr = tls_error(t);
+			fprintf(stderr, "tls_read: %s\n", errstr ? errstr : "");
+			goto err;
+		}
+		len += r;
+
+		if (geminiok) {
+			r = fwrite(buf, 1, r, stdout);
+			if (ferror(stdout)) {
+				fprintf(stderr, "fwrite: stdout: %s\n", strerror(errno));
+				goto err;
+			}
+		}
+
+		if (config_maxresponsesiz && len >= config_maxresponsesiz)
+			break;
+
+	}
+	if (config_maxresponsesiz && len >= config_maxresponsesiz) {
+		fprintf(stderr, "response too big: %zu >= %zu\n",
+				len, config_maxresponsesiz);
+		goto err;
+	}
+	ret = 0;
+
+err:
+	if (t) {
+		tls_close(t);
+		tls_free(t);
+	}
+
+	if (fd != -1)
+		close(fd);
+	return geminiok ? ret : 2;
+}
+
 void
 usage(void)
 {
@@ -783,6 +926,20 @@ main(int argc, char **argv)
 		if (!u.port[0])
 			memcpy(u.port, "70", 3);
 		statuscode = gophers_request();
+	} else if (!strcmp(u.proto, "gemini://")) {
+		if (tls_init())
+			errx(1, "tls_init failed");
+		if (!(tls_config = tls_config_new()))
+			errx(1, "tls config failed");
+		if (config_legacy) {
+			/* enable legacy cipher and negotiation. */
+			if (tls_config_set_ciphers(tls_config, "legacy"))
+				errx(1, "tls set ciphers failed: %s",
+				     tls_config_error(tls_config));
+		}
+		if (!u.port[0])
+			memcpy(u.port, "1965", 5);
+		statuscode = gemini_request();
 	} else {
 		if (u.proto[0])
 			errx(1, "unsupported protocol specified: %s", u.proto);
-- 
2.34.1