Add a test client and fix a couple bugs.

src/ssh/CMakeLists.txt

@@ -32,4 +32,7 @@ target_link_libraries(deuce-ssh_static INTERFACE stdthreads)
 target_link_libraries(deuce-ssh_shared PRIVATE ${OPENSSL_CRYPTO_LIBRARIES})
 target_link_libraries(deuce-ssh_shared PRIVATE stdthreads)
 
+add_executable(client EXCLUDE_FROM_ALL client.c)
+target_link_libraries(client PRIVATE stdthreads deuce-ssh)
+
 install(TARGETS deuce-ssh FILE_SET HEADERS)

src/ssh/client.c

+#include <netinet/in.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <errno.h>
+#include <poll.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <threads.h>
+
+#include "ssh.h"
+
+int sock = -1;
+size_t txbufsz;
+size_t txbuflen;
+uint8_t *txbuf;
+atomic_bool *tx_terminate;
+cnd_t tx_cnd;
+mtx_t tx_mtx;
+struct deuce_ssh_session sess;
+
+int
+tx_thread(void *arg)
+{
+	while ((tx_terminate == NULL || *tx_terminate == false) && (sock != -1)) {
+		mtx_lock(&tx_mtx);
+		if (txbufsz == 0)
+			cnd_wait(&tx_cnd, &tx_mtx);
+		mtx_unlock(&tx_mtx);
+		struct pollfd fd = {
+			.fd = sock,
+			.events = POLLOUT | POLLRDHUP,
+			.revents = 0,
+		};
+		if (poll(&fd, 1, 5000) == 1) {
+			if (fd.revents & POLLOUT) {
+				mtx_lock(&tx_mtx);
+				ssize_t sent = send(sock, txbuf, txbuflen, MSG_NOSIGNAL);
+				if (sent > 0) {
+					memmove(txbuf, &txbuf[sent], txbuflen - sent);
+					txbuflen -= sent;
+				}
+				else if (sent == -1) {
+					switch(errno) {
+						case EAGAIN:
+						case ENOBUFS:
+							break;
+						default:
+							shutdown(sock, SHUT_WR);
+							*tx_terminate = true;
+							break;
+					}
+				}
+				mtx_unlock(&tx_mtx);
+			}
+			if (fd.revents & (POLLHUP | POLLRDHUP)) {
+				shutdown(sock, SHUT_WR);
+				*tx_terminate = true;
+			}
+		}
+	}
+	return 0;
+}
+
+static int
+tx(uint8_t *buf, size_t bufsz, atomic_bool *terminate, void *cbdata)
+{
+	mtx_lock(&tx_mtx);
+	if (txbuflen + bufsz > txbufsz) {
+		uint8_t *nb = realloc(txbuf, txbuflen + bufsz);
+		if (nb == NULL) {
+			mtx_unlock(&tx_mtx);
+			return DEUCE_SSH_ERROR_ALLOC;
+		}
+		else {
+			tx_terminate = terminate;
+			txbuf = nb;
+			memcpy(&txbuf[txbuflen], buf, bufsz);
+			txbufsz = txbuflen + bufsz;
+			if (txbuflen == 0)
+				cnd_signal(&tx_cnd);
+			txbuflen += bufsz;
+		}
+	}
+	mtx_unlock(&tx_mtx);
+	return 0;
+}
+
+static int
+rx(uint8_t *buf, size_t bufsz, atomic_bool *terminate, void *cbdata)
+{
+	size_t rxlen = 0;
+
+	while ((*terminate == false) && (sock != -1) && rxlen < bufsz) {
+		struct pollfd fd = {
+			.fd = sock,
+			.events = POLLIN | POLLRDHUP,
+			.revents = 0,
+		};
+		if (poll(&fd, 1, 5000) == 1) {
+			if (fd.revents & POLLIN) {
+				ssize_t received = recv(sock, &buf[rxlen], bufsz - rxlen, MSG_DONTWAIT);
+				if (received > 0) {
+					rxlen += received;
+				}
+				else if (received == -1) {
+					switch(errno) {
+						case EAGAIN:
+						case EINTR:
+							break;
+						default:
+							shutdown(sock, SHUT_RD);
+							*terminate = true;
+							break;
+					}
+				}
+			}
+			if (fd.revents & (POLLHUP | POLLRDHUP)) {
+				shutdown(sock, SHUT_RD);
+				*terminate = true;
+			}
+		}
+	}
+	return 0;
+}
+
+static int
+rxline(uint8_t *buf, size_t bufsz, size_t *bytes_received, atomic_bool *terminate, void *cbdata)
+{
+	size_t pos = 0;
+	bool lastcr = false;
+
+	for (;;) {
+		int res = rx(&buf[pos], 1, terminate, cbdata);
+		if (res < 0)
+			return res;
+		if (buf[pos] == '\r')
+			lastcr = true;
+		if (buf[pos] == '\n' && lastcr) {
+			*bytes_received = pos + 1;
+			return 0;
+		}
+		if (pos + 1 < bufsz)
+			pos++;
+	}
+}
+
+static int
+extra_line(uint8_t *buf, size_t bufsz, void *cbdata)
+{
+	fprintf(stdout, "%.*s\n", (int)bufsz, buf);
+	return 0;
+}
+
+
+int main(int argc, char **argv)
+{
+	struct sockaddr_in sa = {
+		.sin_len = sizeof(struct sockaddr_in),
+		.sin_family = AF_INET,
+		.sin_port = htons(22),
+		.sin_addr = htonl(0x7f000001),
+	};
+	mtx_init(&tx_mtx, mtx_plain);
+	cnd_init(&tx_cnd);
+	sock = socket(PF_INET, SOCK_STREAM, 0);
+	if (sock == -1)
+		return 1;
+	
+	if (connect(sock, (struct sockaddr *)&sa, sa.sin_len) == -1)
+		return 1;
+	if (deuce_ssh_transport_set_callbacks(tx, rx, rxline, extra_line) != 0)
+		return 1;
+	thrd_t thr;
+	thrd_create(&thr, tx_thread, NULL);
+	deuce_ssh_session_init(&sess);
+	int res;
+	thrd_join(thr, &res);
+}

src/ssh/ssh-trans.c

@@ -32,7 +32,7 @@ static inline bool
 missing_crlf(uint8_t *buf, size_t buflen)
 {
 	assert(buflen >= 2);
-	return (buf[buflen - 1] == '\n' && buf[buflen - 2] == '\r');
+	return (buf[buflen - 1] != '\n' || buf[buflen - 2] != '\r');
 }
 
 static inline bool
@@ -48,7 +48,7 @@ is_20(uint8_t *buf, size_t buflen)
 {
 	if (buflen < 8)
 		return false;
-	return (buf[4] == '2' && buf[5] != '.' && buf[6] != '0' && buf[7] != '-');
+	return (buf[4] == '2' && buf[5] == '.' && buf[6] == '0' && buf[7] == '-');
 }
 
 static inline void *
@@ -144,15 +144,21 @@ tx_handshake(void *arg)
 	memcpy(line, "SSH-2.0-", 8);
 	sz += 8;
 	size_t asz = strlen(gconf.software_version);
+	if (sz + asz + 2 > 255)
+		return DEUCE_SSH_ERROR_TOOLONG;
 	memcpy(&line[sz], gconf.software_version, asz);
 	sz += asz;
 	if (gconf.version_comment != NULL) {
 		memcpy(&line[sz], " ", 1);
 		sz += 1;
 		asz = strlen(gconf.version_comment);
+		if (sz + asz + 2 > 255)
+			return DEUCE_SSH_ERROR_TOOLONG;
 		memcpy(&line[sz], gconf.version_comment, asz);
 		sz += asz;
 	}
+	memcpy(&line[sz], "\r\n", 2);
+	sz += 2;
 	res = gconf.tx(line, sz, &sess->terminate, sess->tx_cbdata);
 	if (res < 0) {
 		sess->terminate = true;

src/ssh/ssh.h

@@ -22,6 +22,7 @@ _Static_assert(0, "threads.h support required");
 #define DEUCE_SSH_ERROR_TERMINATED -5
 #define DEUCE_SSH_ERROR_TOOLATE    -6
 #define DEUCE_SSH_ERROR_TOOMANY    -7
+#define DEUCE_SSH_ERROR_TOOLONG    -8
 
 typedef struct deuce_ssh_transport_state *deuce_ssh_transport_state_t;
 typedef int (*deuce_ssh_transport_io_cb_t)(uint8_t *buf, size_t bufsz, atomic_bool *terminate, void *cbdata);
@@ -50,4 +51,6 @@ int deuce_ssh_session_init(deuce_ssh_session_t sess);
 bool deuce_ssh_session_terminate(deuce_ssh_session_t sess);
 void deuce_ssh_session_cleanup(deuce_ssh_session_t sess);
 
+int deuce_ssh_transport_set_callbacks(deuce_ssh_transport_io_cb_t tx, deuce_ssh_transport_io_cb_t rx, deuce_ssh_transport_rxline_cb_t rx_line, deuce_ssh_transport_extra_line_cb_t extra_line_cb);
+
 #endif