netrc: Implement .netrc parsing

src/Makefile.am

@@ -12,6 +12,8 @@ axel_SOURCES = \
 	src/ftp.h \
 	src/http.c \
 	src/http.h \
+	src/netrc.c \
+	src/netrc.h \
 	src/search.c \
 	src/search.h \
 	src/ssl.c \

src/conf.h

@@ -43,6 +43,7 @@
 #define AXEL_CONF_H
 
 typedef struct {
+	char netrc_filename[MAX_STRING];
 	char default_filename[MAX_STRING];
 	char http_proxy[MAX_STRING];
 	char no_proxy[MAX_STRING];
@@ -67,6 +68,7 @@ typedef struct {
 	int search_threads;
 	int search_amount;
 	int search_top;
+	int use_netrc;
 
 	unsigned io_timeout;
 

src/conn.c

@@ -43,6 +43,7 @@
 /* Connection stuff */
 
 #include "axel.h"
+#include "netrc.h"
 
 /**
  * Convert an URL to a conn_t structure.
@@ -253,6 +254,8 @@ conn_init(conn_t *conn)
 		conn->ftp->local_if = conn->local_if;
 		conn->ftp->ftp_mode = FTP_PASSIVE;
 		conn->ftp->tcp.ai_family = conn->conf->ai_family;
+		if (conn->conf->use_netrc)
+			netrc_parse(conn);
 		if (!ftp_connect(conn->ftp, conn->proto, conn->host, conn->port,
 				 conn->user, conn->pass,
 				 conn->conf->io_timeout)) {

src/netrc.c

@@ -0,0 +1,114 @@
+/*
+  Axel -- A lighter download accelerator for Linux and other Unices
+
+  Copyright 2019      David da Silva Polverari
+
+  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 2
+  of the License, or (at your option) any later version.
+
+  In addition, as a special exception, the copyright holders give
+  permission to link the code of portions of this program with the
+  OpenSSL library under certain conditions as described in each
+  individual source file, and distribute linked combinations including
+  the two.
+
+  You must obey the GNU General Public License in all respects for all
+  of the code used other than OpenSSL. If you modify file(s) with this
+  exception, you may extend this exception to your version of the
+  file(s), but you are not obligated to do so. If you do not wish to do
+  so, delete this exception statement from your version. If you delete
+  this exception statement from all source files in the program, then
+  also delete it here.
+
+  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, write to the Free Software
+  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+*/
+
+/* .netrc parsing implementation */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdbool.h>
+#include "axel.h"
+#include "netrc.h"
+
+enum lookup_state {
+	NOTHING,
+	DEFAULT,
+	MACHINE,
+	HOST_ENTRY,
+	LOGIN,
+	PASSWORD
+};
+
+void
+netrc_parse(conn_t *conn)
+{
+	FILE *fp;
+	bool found = false;
+	char *home;
+	char *tok, *ntok;
+	char line[MAX_STRING];
+	char const *delims = " \t\n";
+	enum lookup_state state = NOTHING;
+
+	if (conn->conf->netrc_filename[0] == '\0') {
+		home = getenv("HOME");
+		snprintf(conn->conf->netrc_filename, MAX_STRING, "%s/.netrc", home);
+	}
+	if ((fp = fopen(conn->conf->netrc_filename, "r")) == NULL)
+		return;
+	while (!found && fgets(line, MAX_STRING, fp)) {
+		tok = strtok_r(line, delims, &ntok);
+		if (tok && *tok == '#')
+			continue;
+		while (tok != NULL) {
+			switch (state) {
+			case NOTHING:
+				if (!strcmp("machine", tok)) {
+					state = MACHINE;
+				} else if (!strcmp("default", tok)) {
+					state = DEFAULT;
+				}
+				break;
+			case MACHINE:
+				if (!strcmp(conn->host, tok)) {
+					state = HOST_ENTRY;
+				} else {
+					state = NOTHING;
+				}
+				break;
+			case DEFAULT:
+				state = HOST_ENTRY;
+				// fall through
+			case HOST_ENTRY:
+				if (!strcmp("login", tok)) {
+					state = LOGIN;
+				} else if (!strcmp("password", tok)) {
+					state = PASSWORD;
+				}
+				break;
+			case LOGIN:
+				strcpy(conn->user, tok);
+				state = HOST_ENTRY;
+				break;
+			case PASSWORD:
+				strcpy(conn->pass, tok);
+				found = true;
+				break;
+			default:
+				break;
+			}
+			tok = strtok_r(NULL, delims, &ntok);
+		}
+	}
+}

src/netrc.h

@@ -0,0 +1,42 @@
+/*
+  Axel -- A lighter download accelerator for Linux and other Unices
+
+  Copyright 2019      David da Silva Polverari
+
+  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 2
+  of the License, or (at your option) any later version.
+
+  In addition, as a special exception, the copyright holders give
+  permission to link the code of portions of this program with the
+  OpenSSL library under certain conditions as described in each
+  individual source file, and distribute linked combinations including
+  the two.
+
+  You must obey the GNU General Public License in all respects for all
+  of the code used other than OpenSSL. If you modify file(s) with this
+  exception, you may extend this exception to your version of the
+  file(s), but you are not obligated to do so. If you do not wish to do
+  so, delete this exception statement from your version. If you delete
+  this exception statement from all source files in the program, then
+  also delete it here.
+
+  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, write to the Free Software
+  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+*/
+
+/* .netrc parsing include file */
+
+#ifndef AXEL_NETRC_H
+#define AXEL_NETRC_H
+
+void netrc_parse(conn_t *conn);
+
+#endif				/* AXEL_NETRC_H */

src/text.c

@@ -71,6 +71,7 @@ static struct option axel_options[] = {
 	{"max-redirect",    1,      NULL, MAX_REDIR_OPT},
 	{"output",          1,      NULL, 'o'},
 	{"search",          2,      NULL, 'S'},
+	{"netrc",           2,      NULL, 'R'},
 	{"ipv4",            0,      NULL, '4'},
 	{"ipv6",            0,      NULL, '6'},
 	{"no-proxy",        0,      NULL, 'N'},
@@ -117,7 +118,7 @@ main(int argc, char *argv[])
 	j = -1;
 	while (1) {
 		int option = getopt_long(argc, argv,
-					 "s:n:o:S::46NqvhVakcH:U:T:",
+					 "s:n:o:S::R::46NqvhVakcH:U:T:",
 					 axel_options, NULL);
 		if (option == -1)
 			break;
@@ -161,6 +162,15 @@ main(int argc, char *argv[])
 				}
 			}
 			break;
+		case 'R':
+			conf->use_netrc = 1;
+			if (optarg) {
+				if (!sscanf(optarg, "%s", conf->netrc_filename)) {
+					print_help();
+					goto free_conf;
+				}
+			}
+			break;
 		case '6':
 			conf->ai_family = AF_INET6;
 			break;
@@ -659,6 +669,7 @@ print_help(void)
 		 "-n x\tSpecify maximum number of connections\n"
 		 "-o f\tSpecify local output file\n"
 		 "-S[n]\tSearch for mirrors and download from n servers\n"
+		 "-R[file]\tRetrieve credentials from $HOME/.netrc file or filename\n"
 		 "-4\tUse the IPv4 protocol\n"
 		 "-6\tUse the IPv6 protocol\n"
 		 "-H x\tAdd HTTP header string\n"
@@ -682,6 +693,7 @@ print_help(void)
 		 "--max-redirect=x\t\tSpecify maximum number of redirections\n"
 		 "--output=f\t\t-o f\tSpecify local output file\n"
 		 "--search[=n]\t\t-S[n]\tSearch for mirrors and download from n servers\n"
+		 "--netrc[=file]\t\t-R[file]\tRetrieve credentials from $HOME/.netrc file or filename\n"
 		 "--ipv4\t\t\t-4\tUse the IPv4 protocol\n"
 		 "--ipv6\t\t\t-6\tUse the IPv6 protocol\n"
 		 "--header=x\t\t-H x\tAdd HTTP header string\n"