1 files changed, 112 insertions, 57 deletions

diff --git a/imap.c b/imap.c
index 7984e0e..c24fd42 100644
--- a/imap.c
+++ b/imap.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2020  C. McEnroe <june@causal.agency>
+/* Copyright (C) 2020  June 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
@@ -12,20 +12,46 @@
  *
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ * Additional permission under GNU GPL version 3 section 7:
+ *
+ * If you modify this Program, or any covered work, by linking or
+ * combining it with OpenSSL (or a modified version of that library),
+ * containing parts covered by the terms of the OpenSSL License and the
+ * original SSLeay license, the licensors of this Program grant you
+ * additional permission to convey the resulting work. Corresponding
+ * Source for a non-source form of such a combination shall include the
+ * source code for the parts of OpenSSL used as well as that of the
+ * covered work.
  */
 
-#include "compat.h"
-
 #include <err.h>
+#include <netdb.h>
+#include <netinet/in.h>
 #include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <sys/socket.h>
 #include <sysexits.h>
 #include <tls.h>
+#include <unistd.h>
+
+FILE *funopen(
+	const void *cookie,
+	int (*readfn)(void *, char *, int),
+	int (*writefn)(void *, const char *, int),
+	fpos_t (*seekfn)(void *, fpos_t, int),
+	int (*closefn)(void *)
+);
 
 #include "imap.h"
 
+int getservinfo(
+	const char *hostname, const char *servname,
+	const struct addrinfo *hints, struct addrinfo **res
+);
+
 const char *Atoms[AtomCap] = {
 #define X(id, str) [id] = str,
 	ENUM_ATOM
@@ -64,7 +90,7 @@ static int imapClose(void *_tls) {
 	return error;
 }
 
-void imapOpen(FILE **read, FILE **write, const char *host, const char *port) {
+struct IMAP imapOpen(const char *host, const char *port) {
 	struct tls *client = tls_client();
 	if (!client) errx(EX_SOFTWARE, "tls_client");
 
@@ -75,99 +101,128 @@ void imapOpen(FILE **read, FILE **write, const char *host, const char *port) {
 	if (error) errx(EX_SOFTWARE, "tls_configure: %s", tls_error(client));
 	tls_config_free(config);
 
-	error = tls_connect(client, host, port);
-	if (error) errx(EX_NOHOST, "tls_connect: %s", tls_error(client));
+	struct addrinfo *head;
+	struct addrinfo hints = {
+		.ai_family = PF_UNSPEC,
+		.ai_socktype = SOCK_STREAM,
+		.ai_protocol = IPPROTO_TCP,
+	};
+	error = getservinfo(host, port, &hints, &head);
+	if (error) errx(EX_NOHOST, "%s:%s: %s", host, port, gai_strerror(error));
 
-	*read = funopen(client, imapRead, NULL, NULL, NULL);
-	*write = funopen(client, NULL, imapWrite, NULL, imapClose);
-	if (!*read || !*write) err(EX_SOFTWARE, "funopen");
+	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");
 
-	setlinebuf(*write);
-}
+		error = connect(sock, ai->ai_addr, ai->ai_addrlen);
+		if (!error) break;
 
-static size_t cap;
-static char *buf;
-static char *ptr;
+		close(sock);
+		sock = -1;
+	}
+	if (sock < 0) err(EX_UNAVAILABLE, "%s:%s", host, port);
 
-static void imapLine(FILE *imap) {
-	ssize_t len = getline(&buf, &cap, imap);
+	error = tls_connect_socket(
+		client, sock, (head->ai_canonname ? head->ai_canonname : host)
+	);
+	if (error) errx(EX_SOFTWARE, "tls_connect_socket: %s", tls_error(client));
+	freeaddrinfo(head);
+
+	struct IMAP imap = {
+		.sock = sock,
+		.r = funopen(client, imapRead, NULL, NULL, NULL),
+		.w = funopen(client, NULL, imapWrite, NULL, imapClose),
+	};
+	if (!imap.r || !imap.w) err(EX_OSERR, "funopen");
+
+	setlinebuf(imap.w);
+	return imap;
+}
+
+static void imapLine(struct IMAP *imap) {
+	ssize_t len = getline(&imap->buf, &imap->cap, imap->r);
 	if (len < 0) errx(EX_PROTOCOL, "unexpected eof");
-	if (len < 1 || buf[len - 1] != '\n') errx(EX_PROTOCOL, "missing LF");
-	if (len < 2 || buf[len - 2] != '\r') errx(EX_PROTOCOL, "missing CR");
-	buf[len - 2] = '\0';
-	ptr = buf;
+	if (len < 1 || imap->buf[len - 1] != '\n') errx(EX_PROTOCOL, "missing LF");
+	if (len < 2 || imap->buf[len - 2] != '\r') errx(EX_PROTOCOL, "missing CR");
+	imap->buf[len - 2] = '\0';
+	imap->ptr = imap->buf;
 }
 
-static struct Data parseAtom(void) {
-	size_t len = (*ptr == '.' ? 1 : strcspn(ptr, " .()[]{\""));
+static struct Data parseAtom(struct IMAP *imap) {
+	size_t len = (*imap->ptr == '.' ? 1 : strcspn(imap->ptr, " .()[]{\""));
 	struct Data data = {
 		.type = Atom,
-		.atom = atomn(ptr, len),
+		.atom = atomn(imap->ptr, len),
 	};
-	ptr += len;
+	imap->ptr += len;
 	return data;
 }
 
-static struct Data parseNumber(void) {
+static struct Data parseNumber(struct IMAP *imap) {
 	return (struct Data) {
 		.type = Number,
-		.number = strtoull(ptr, &ptr, 10),
+		.number = strtoull(imap->ptr, &imap->ptr, 10),
 	};
 }
 
-static struct Data parseQuoted(void) {
-	ptr++;
-	size_t len = strcspn(ptr, "\"");
-	if (ptr[len] != '"') errx(EX_PROTOCOL, "missing quoted string delimiter");
+static struct Data parseQuoted(struct IMAP *imap) {
+	imap->ptr++;
+	size_t len = strcspn(imap->ptr, "\"");
+	if (imap->ptr[len] != '"') {
+		errx(EX_PROTOCOL, "missing quoted string delimiter");
+	}
 	struct Data data = {
 		.type = String,
-		.string = strndup(ptr, len),
+		.string = strndup(imap->ptr, len),
 	};
 	if (!data.string) err(EX_OSERR, "strndup");
-	ptr += len + 1;
+	imap->ptr += len + 1;
 	return data;
 }
 
-static struct Data parseLiteral(FILE *imap) {
-	ptr++;
-	size_t len = strtoull(ptr, &ptr, 10);
-	if (*ptr != '}') errx(EX_PROTOCOL, "missing literal prefix delimiter");
+static struct Data parseLiteral(struct IMAP *imap) {
+	imap->ptr++;
+	size_t len = strtoull(imap->ptr, &imap->ptr, 10);
+	if (*imap->ptr != '}') {
+		errx(EX_PROTOCOL, "missing literal prefix delimiter");
+	}
 	struct Data data = {
 		.type = String,
 		.string = malloc(len + 1),
 	};
 	if (!data.string) err(EX_OSERR, "malloc");
-	size_t n = fread(data.string, len, 1, imap);
+	size_t n = fread(data.string, len, 1, imap->r);
 	if (!n) errx(EX_PROTOCOL, "truncated literal");
 	imapLine(imap);
 	data.string[len] = '\0';
 	return data;
 }
 
-static struct Data parseData(FILE *imap);
+static struct Data parseData(struct IMAP *imap);
 
-static struct Data parseList(FILE *imap, char close) {
-	if (*ptr) ptr++;
+static struct Data parseList(struct IMAP *imap, char close) {
+	if (*imap->ptr) imap->ptr++;
 	struct Data data = { .type = List };
-	while (*ptr != close) {
+	while (*imap->ptr != close) {
 		listPush(&data.list, parseData(imap));
 	}
-	if (*ptr) ptr++;
+	if (*imap->ptr) imap->ptr++;
 	return data;
 }
 
-static struct Data parseData(FILE *imap) {
-	if (*ptr == ' ') ptr++;
-	if (*ptr == '"') return parseQuoted();
-	if (*ptr == '{') return parseLiteral(imap);
-	if (*ptr == '(') return parseList(imap, ')');
-	if (*ptr == '[') return parseList(imap, ']');
-	if (*ptr >= '0' && *ptr <= '9') return parseNumber();
-	if (*ptr) return parseAtom();
+static struct Data parseData(struct IMAP *imap) {
+	if (*imap->ptr == ' ') imap->ptr++;
+	if (*imap->ptr == '"') return parseQuoted(imap);
+	if (*imap->ptr == '{') return parseLiteral(imap);
+	if (*imap->ptr == '(') return parseList(imap, ')');
+	if (*imap->ptr == '[') return parseList(imap, ']');
+	if (*imap->ptr >= '0' && *imap->ptr <= '9') return parseNumber(imap);
+	if (*imap->ptr) return parseAtom(imap);
 	errx(EX_PROTOCOL, "unexpected eof");
 }
 
-struct Resp imapResp(FILE *imap) {
+struct Resp imapResp(struct IMAP *imap) {
 	struct Data data;
 	struct Resp resp = {0};
 	imapLine(imap);
@@ -176,8 +231,8 @@ struct Resp imapResp(FILE *imap) {
 	if (data.type != Atom) errx(EX_PROTOCOL, "expected tag atom");
 	resp.tag = data.atom;
 	if (resp.tag == AtomContinue) {
-		if (*ptr == ' ') ptr++;
-		resp.text = ptr;
+		if (*imap->ptr == ' ') imap->ptr++;
+		resp.text = imap->ptr;
 		return resp;
 	}
 
@@ -196,13 +251,13 @@ struct Resp imapResp(FILE *imap) {
 		resp.resp == AtomPreauth ||
 		resp.resp == AtomBye
 	) {
-		if (*ptr == ' ') ptr++;
-		if (*ptr == '[') {
+		if (*imap->ptr == ' ') imap->ptr++;
+		if (*imap->ptr == '[') {
 			data = parseList(imap, ']');
 			resp.code = data.list;
 		}
-		if (*ptr == ' ') ptr++;
-		resp.text = ptr;
+		if (*imap->ptr == ' ') imap->ptr++;
+		resp.text = imap->ptr;
 	} else {
 		data = parseList(imap, '\0');
 		resp.data = data.list;