netrc: Implement .netrc parsing

src/conn.c

@@ -255,7 +255,7 @@ conn_init(conn_t *conn)
 		conn->ftp->ftp_mode = FTP_PASSIVE;
 		conn->ftp->tcp.ai_family = conn->conf->ai_family;
 		if (conn->conf->use_netrc)
-			netrc_parse(conn->conf->netrc_filename, conn->host, conn->user, conn->pass);
+			netrc_parse(conn->conf->netrc_filename, conn->host, conn->user, sizeof(conn->user), conn->pass, sizeof(conn->pass));
 		printf("host: %s, user: %s, pass: %s\n", conn->host, conn->user, conn->pass);
 		if (!ftp_connect(conn->ftp, conn->proto, conn->host, conn->port,
 				 conn->user, conn->pass,

src/netrc.c

@@ -41,75 +41,95 @@
 #include <unistd.h>
 #include <sys/stat.h>
 #include <sys/mman.h>
+#include "axel.h"
 #include "netrc.h"
 
-#define REL_NETRC	"/.netrc"
-#define IS_DELIM(x)	(*x == ' ' || *x == '\t' || *x == '\n')
-
-static int fd;
-static size_t sz;
 static char *p;
 static char *s_addr;
 static char *e_addr;
 
-static size_t file_size(void)
+static size_t file_size(int fd)
 {
 	struct stat st;
 	fstat(fd, &st);
 	return st.st_size;
 }
 
-static int netrc_open(const char * const filename)
+static int netrc_mmap(const char *filename)
 {
-	int ret;
-	char *path;
-	char *netrc;
-	char *home;
-
-	ret = 0;
-	if (filename && filename[0] != '\0') {
-		path = strdup(filename);
-	} else {
-		if ((netrc = getenv("NETRC"))) {
-			path = strdup(netrc);
-		} else if ((home = getenv("HOME"))) {
-			size_t i = strlen(home) + strlen(REL_NETRC) + 1;
-			path = malloc(i);
-			snprintf(path, i, "%s%s", home, REL_NETRC);
-		} else {
-			return ret;
+	int fd;
+	size_t sz;
+	char *aux = NULL;
+	char *home = NULL;
+	char *path = NULL;
+	const char suffix[] = "/.netrc";
+
+	if (filename && *filename) {
+		aux = path = (char *)filename;
+	} else if ((path = getenv("NETRC"))) {
+		aux = path;
+	} else if ((home = getenv("HOME"))) {
+		size_t i = strlen(home);
+		if ((path = malloc(i + sizeof(suffix)))) {
+			memcpy(path, home, i);
+			memcpy(path+i, suffix, sizeof(suffix));
 		}
 	}
-	if ((fd = open(path, O_RDONLY, 0)) == -1) {
-		ret = 0;
+	if (!path)
+		return 0;
+	fd = open(path, O_RDONLY,0);
+	if (!aux)
+		free(path);
+	if (fd == -1) {
+		return 0;
 	} else {
-		sz = file_size();
+		sz = file_size(fd);
 		s_addr = mmap(NULL, sz, PROT_READ, MAP_PRIVATE | MAP_POPULATE, fd, 0);
+		close(fd);
 		e_addr = s_addr + sz;
-		ret = 1;
+		return sz;
 	}
-	free(path);
-	return ret;
 }
 
-static void netrc_close(void)
+static void netrc_munmap(size_t sz)
 {
 	munmap(s_addr, sz);
-	close(fd);
 }
 
-static int next_token(char **t)
+static size_t
+memspn(const char *s, const char *t, size_t len)
+{
+	size_t sz = 0;
+
+	while (*s && len-- && strchr(t, *s++))
+		sz++;
+	return sz;
+}
+
+static size_t
+memcspn(const char *s, const char *t, size_t len)
+{
+	size_t sz = 0;
+
+	while (*s && len--)
+		if (strchr(t, *s))
+			return sz;
+		else
+			s++, sz++;
+	return sz;
+}
+
+static size_t next_token(char **t)
 {
 	char *q;
-	int len;
+	size_t len;
+	const char *delims = " \t\n";
 
 	if (!p)
 		p = s_addr;
-	while (IS_DELIM(p) && p < e_addr)
-		p++;
+	p += memspn(p, delims, (e_addr - p));
 	q = p;
-	while (!IS_DELIM(q) && q < e_addr)
-		q++;
+	q += memcspn(q, delims, (e_addr - q));
 	if (q == e_addr)
 		return 0;
 	len = q-p;
@@ -118,20 +138,22 @@ static int next_token(char **t)
 	return len;
 }
 
-static void get_creds(char *user, char *pwd)
+static void
+get_creds(char *user, size_t ul, char *pwd, size_t pl)
 {
-	int len;
+	size_t len;
 	char *tok;
 
 	while ((len = next_token(&tok))) {
 		if (!strncmp("login", tok, len)) {
 			len = next_token(&tok);
-			strncpy(user, tok, len);
-			user[len] = '\0';
+			/* next_token() doesn't null-terminate */
+			if (len <= ul)
+				strlcpy(user, tok, len+1);
 		} else if (!strncmp("password", tok, len)) {
 			len = next_token(&tok);
-			strncpy(pwd, tok, len);
-			pwd[len] = '\0';
+			if (len <= pl)
+				strlcpy(pwd, tok, len+1);
 		} else if (!strncmp("machine", tok, len) || !strncmp("default", tok, len)) {
 			p -= len;
 			break;
@@ -140,24 +162,26 @@ static void get_creds(char *user, char *pwd)
 }
 
 int
-netrc_parse(const char *filename, const char *host, char *user, char *password)
+netrc_parse(const char *filename, const char *host,
+	    char *user, size_t ul, char *password, size_t pl)
 {
-	int len;
+	size_t len;
+	size_t sz;
 	char *tok;
 
-	if (!netrc_open(filename))
+	if (!(sz = netrc_mmap(filename)))
 		return 0;
 	while ((len = next_token(&tok))) {
 		if (!strncmp("default", tok, len)) {
-			get_creds(user, password);
+			get_creds(user, ul, password, pl);
 			break;
 		} else if (!strncmp("machine", tok, len)) {
 			if ((len = next_token(&tok)) && !strncmp(host, tok, len)) {
-				get_creds(user, password);
+				get_creds(user, ul, password, pl);
 				break;
 			}
 		}
 	}
-	netrc_close();
-	return 0;
+	netrc_munmap(sz);
+	return 1;
 }

src/netrc.h

@@ -37,6 +37,6 @@
 #ifndef AXEL_NETRC_H
 #define AXEL_NETRC_H
 
-int netrc_parse(const char *filename, const char *host, char *user, char *pwd);
+int netrc_parse(const char *filename, const char *host, char *user, size_t ul, char *pwd, size_t pl);
 
 #endif				/* AXEL_NETRC_H */

src/text.c

@@ -165,7 +165,8 @@ main(int argc, char *argv[])
 		case 'R':
 			conf->use_netrc = 1;
 			if (optarg) {
-				if (!sscanf(optarg, "%s", conf->netrc_filename)) {
+				if (!strlcpy(conf->netrc_filename, optarg, 
+				     sizeof(conf->netrc_filename))) {
 					print_help();
 					goto free_conf;
 				}