Rewrite the implementation of the ssh block driver to use libssh instead of libssh2. The libssh library has various advantages over libssh2: - easier API for authentication (for example for using ssh-agent) - easier API for known_hosts handling - supports newer types of keys in known_hosts
Kerberos authentication can be enabled once the libssh bug for it [1] is fixed. The development version of libssh (i.e. the future 0.8.x) supports fsync, so reuse the build time check for this. [1] https://red.libssh.org/issues/242 Signed-off-by: Pino Toscano <ptosc...@redhat.com> --- Changes from v4: - fix wrong usages of error_setg/session_error_setg/sftp_error_setg - fix few return code checks - remove now-unused parameters in few internal functions - allow authentication with "none" method - switch to unsigned int for the port number - enable TCP_NODELAY on the socket - fix one reference error message in iotest 207 Changes from v3: - fix socket cleanup in connect_to_ssh() - add comments about the socket cleanup - improve the error reporting (closer to what was with libssh2) - improve EOF detection on sftp_read() Changes from v2: - used again an own fd - fixed co_yield() implementation Changes from v1: - fixed jumbo packets writing - fixed missing 'err' assignment - fixed commit message block/Makefile.objs | 6 +- block/ssh.c | 566 ++++++++++++++++++------------------- configure | 65 +++-- tests/qemu-iotests/207.out | 2 +- 4 files changed, 307 insertions(+), 332 deletions(-) diff --git a/block/Makefile.objs b/block/Makefile.objs index 899bfb5e2c..9c3b3bfb99 100644 --- a/block/Makefile.objs +++ b/block/Makefile.objs @@ -21,7 +21,7 @@ block-obj-$(CONFIG_CURL) += curl.o block-obj-$(CONFIG_RBD) += rbd.o block-obj-$(CONFIG_GLUSTERFS) += gluster.o block-obj-$(CONFIG_VXHS) += vxhs.o -block-obj-$(CONFIG_LIBSSH2) += ssh.o +block-obj-$(CONFIG_LIBSSH) += ssh.o block-obj-y += accounting.o dirty-bitmap.o block-obj-y += write-threshold.o block-obj-y += backup.o @@ -42,8 +42,8 @@ rbd.o-libs := $(RBD_LIBS) gluster.o-cflags := $(GLUSTERFS_CFLAGS) gluster.o-libs := $(GLUSTERFS_LIBS) vxhs.o-libs := $(VXHS_LIBS) -ssh.o-cflags := $(LIBSSH2_CFLAGS) -ssh.o-libs := $(LIBSSH2_LIBS) +ssh.o-cflags := $(LIBSSH_CFLAGS) +ssh.o-libs := $(LIBSSH_LIBS) block-obj-$(if $(CONFIG_BZIP2),m,n) += dmg-bz2.o dmg-bz2.o-libs := $(BZIP2_LIBS) qcow.o-libs := -lz diff --git a/block/ssh.c b/block/ssh.c index da7bbf73e2..787245230a 100644 --- a/block/ssh.c +++ b/block/ssh.c @@ -24,8 +24,8 @@ #include "qemu/osdep.h" -#include <libssh2.h> -#include <libssh2_sftp.h> +#include <libssh/libssh.h> +#include <libssh/sftp.h> #include "block/block_int.h" #include "block/qdict.h" @@ -45,14 +45,12 @@ /* DEBUG_SSH=1 enables the DPRINTF (debugging printf) statements in * this block driver code. * - * TRACE_LIBSSH2=<bitmask> enables tracing in libssh2 itself. Note - * that this requires that libssh2 was specially compiled with the - * `./configure --enable-debug' option, so most likely you will have - * to compile it yourself. The meaning of <bitmask> is described - * here: http://www.libssh2.org/libssh2_trace.html + * TRACE_LIBSSH=<level> enables tracing in libssh itself. + * The meaning of <level> is described here: + * http://api.libssh.org/master/group__libssh__log.html */ #define DEBUG_SSH 0 -#define TRACE_LIBSSH2 0 /* or try: LIBSSH2_TRACE_SFTP */ +#define TRACE_LIBSSH 0 /* see: SSH_LOG_* */ #define DPRINTF(fmt, ...) \ do { \ @@ -68,18 +66,14 @@ typedef struct BDRVSSHState { /* SSH connection. */ int sock; /* socket */ - LIBSSH2_SESSION *session; /* ssh session */ - LIBSSH2_SFTP *sftp; /* sftp session */ - LIBSSH2_SFTP_HANDLE *sftp_handle; /* sftp remote file handle */ + ssh_session session; /* ssh session */ + sftp_session sftp; /* sftp session */ + sftp_file sftp_handle; /* sftp remote file handle */ - /* See ssh_seek() function below. */ - int64_t offset; - bool offset_op_read; - - /* File attributes at open. We try to keep the .filesize field + /* File attributes at open. We try to keep the .size field * updated if it changes (eg by writing at the end of the file). */ - LIBSSH2_SFTP_ATTRIBUTES attrs; + sftp_attributes attrs; InetSocketAddress *inet; @@ -91,27 +85,25 @@ static void ssh_state_init(BDRVSSHState *s) { memset(s, 0, sizeof *s); s->sock = -1; - s->offset = -1; qemu_co_mutex_init(&s->lock); } static void ssh_state_free(BDRVSSHState *s) { + if (s->attrs) { + sftp_attributes_free(s->attrs); + } if (s->sftp_handle) { - libssh2_sftp_close(s->sftp_handle); + sftp_close(s->sftp_handle); } if (s->sftp) { - libssh2_sftp_shutdown(s->sftp); + sftp_free(s->sftp); } if (s->session) { - libssh2_session_disconnect(s->session, - "from qemu ssh client: " - "user closed the connection"); - libssh2_session_free(s->session); - } - if (s->sock >= 0) { - close(s->sock); + ssh_disconnect(s->session); + ssh_free(s->session); } + /* s->sock is owned by the ssh_session, which frees it. */ } static void GCC_FMT_ATTR(3, 4) @@ -125,13 +117,13 @@ session_error_setg(Error **errp, BDRVSSHState *s, const char *fs, ...) va_end(args); if (s->session) { - char *ssh_err; + const char *ssh_err; int ssh_err_code; - /* This is not an errno. See <libssh2.h>. */ - ssh_err_code = libssh2_session_last_error(s->session, - &ssh_err, NULL, 0); - error_setg(errp, "%s: %s (libssh2 error code: %d)", + /* This is not an errno. See <libssh/libssh.h>. */ + ssh_err = ssh_get_error(s->session); + ssh_err_code = ssh_get_error_code(s->session); + error_setg(errp, "%s: %s (libssh error code: %d)", msg, ssh_err, ssh_err_code); } else { error_setg(errp, "%s", msg); @@ -150,18 +142,18 @@ sftp_error_setg(Error **errp, BDRVSSHState *s, const char *fs, ...) va_end(args); if (s->sftp) { - char *ssh_err; + const char *ssh_err; int ssh_err_code; - unsigned long sftp_err_code; + int sftp_err_code; - /* This is not an errno. See <libssh2.h>. */ - ssh_err_code = libssh2_session_last_error(s->session, - &ssh_err, NULL, 0); - /* See <libssh2_sftp.h>. */ - sftp_err_code = libssh2_sftp_last_error((s)->sftp); + /* This is not an errno. See <libssh/libssh.h>. */ + ssh_err = ssh_get_error(s->session); + ssh_err_code = ssh_get_error_code(s->session); + /* See <libssh/sftp.h>. */ + sftp_err_code = sftp_get_error(s->sftp); error_setg(errp, - "%s: %s (libssh2 error code: %d, sftp error code: %lu)", + "%s: %s (libssh error code: %d, sftp error code: %d)", msg, ssh_err, ssh_err_code, sftp_err_code); } else { error_setg(errp, "%s", msg); @@ -178,17 +170,17 @@ sftp_error_report(BDRVSSHState *s, const char *fs, ...) error_vprintf(fs, args); if ((s)->sftp) { - char *ssh_err; + const char *ssh_err; int ssh_err_code; - unsigned long sftp_err_code; + int sftp_err_code; - /* This is not an errno. See <libssh2.h>. */ - ssh_err_code = libssh2_session_last_error(s->session, - &ssh_err, NULL, 0); - /* See <libssh2_sftp.h>. */ - sftp_err_code = libssh2_sftp_last_error((s)->sftp); + /* This is not an errno. See <libssh/libssh.h>. */ + ssh_err = ssh_get_error(s->session); + ssh_err_code = ssh_get_error_code(s->session); + /* See <libssh/sftp.h>. */ + sftp_err_code = sftp_get_error(s->sftp); - error_printf(": %s (libssh2 error code: %d, sftp error code: %lu)", + error_printf(": %s (libssh error code: %d, sftp error code: %d)", ssh_err, ssh_err_code, sftp_err_code); } @@ -292,71 +284,41 @@ static void ssh_parse_filename(const char *filename, QDict *options, parse_uri(filename, options, errp); } -static int check_host_key_knownhosts(BDRVSSHState *s, - const char *host, int port, Error **errp) +static int check_host_key_knownhosts(BDRVSSHState *s, Error **errp) { - const char *home; - char *knh_file = NULL; - LIBSSH2_KNOWNHOSTS *knh = NULL; - struct libssh2_knownhost *found; - int ret, r; - const char *hostkey; - size_t len; - int type; + int ret; + int state; - hostkey = libssh2_session_hostkey(s->session, &len, &type); - if (!hostkey) { - ret = -EINVAL; - session_error_setg(errp, s, "failed to read remote host key"); - goto out; - } + state = ssh_is_server_known(s->session); - knh = libssh2_knownhost_init(s->session); - if (!knh) { - ret = -EINVAL; - session_error_setg(errp, s, - "failed to initialize known hosts support"); - goto out; - } - - home = getenv("HOME"); - if (home) { - knh_file = g_strdup_printf("%s/.ssh/known_hosts", home); - } else { - knh_file = g_strdup_printf("/root/.ssh/known_hosts"); - } - - /* Read all known hosts from OpenSSH-style known_hosts file. */ - libssh2_knownhost_readfile(knh, knh_file, LIBSSH2_KNOWNHOST_FILE_OPENSSH); - - r = libssh2_knownhost_checkp(knh, host, port, hostkey, len, - LIBSSH2_KNOWNHOST_TYPE_PLAIN| - LIBSSH2_KNOWNHOST_KEYENC_RAW, - &found); - switch (r) { - case LIBSSH2_KNOWNHOST_CHECK_MATCH: + switch (state) { + case SSH_SERVER_KNOWN_OK: /* OK */ - DPRINTF("host key OK: %s", found->key); break; - case LIBSSH2_KNOWNHOST_CHECK_MISMATCH: + case SSH_SERVER_KNOWN_CHANGED: ret = -EINVAL; - session_error_setg(errp, s, - "host key does not match the one in known_hosts" - " (found key %s)", found->key); + error_setg(errp, "host key does not match the one in known_hosts"); goto out; - case LIBSSH2_KNOWNHOST_CHECK_NOTFOUND: + case SSH_SERVER_FOUND_OTHER: ret = -EINVAL; - session_error_setg(errp, s, "no host key was found in known_hosts"); + error_setg(errp, + "host key for this server not found, another type exists"); goto out; - case LIBSSH2_KNOWNHOST_CHECK_FAILURE: + case SSH_SERVER_FILE_NOT_FOUND: + ret = -ENOENT; + error_setg(errp, "known_hosts file not found"); + goto out; + case SSH_SERVER_NOT_KNOWN: + ret = -EINVAL; + error_setg(errp, "no host key was found in known_hosts"); + goto out; + case SSH_SERVER_ERROR: ret = -EINVAL; - session_error_setg(errp, s, - "failure matching the host key with known_hosts"); + error_setg(errp, "server error"); goto out; default: ret = -EINVAL; - session_error_setg(errp, s, "unknown error matching the host key" - " with known_hosts (%d)", r); + error_setg(errp, "error while checking for known server"); goto out; } @@ -364,10 +326,6 @@ static int check_host_key_knownhosts(BDRVSSHState *s, ret = 0; out: - if (knh != NULL) { - libssh2_knownhost_free(knh); - } - g_free(knh_file); return ret; } @@ -411,18 +369,30 @@ static int compare_fingerprint(const unsigned char *fingerprint, size_t len, static int check_host_key_hash(BDRVSSHState *s, const char *hash, - int hash_type, size_t fingerprint_len, Error **errp) + enum ssh_publickey_hash_type type, Error **errp) { - const char *fingerprint; + int r; + ssh_key pubkey; + unsigned char *server_hash; + size_t server_hash_len; - fingerprint = libssh2_hostkey_hash(s->session, hash_type); - if (!fingerprint) { + r = ssh_get_publickey(s->session, &pubkey); + if (r != SSH_OK) { session_error_setg(errp, s, "failed to read remote host key"); return -EINVAL; } - if(compare_fingerprint((unsigned char *) fingerprint, fingerprint_len, - hash) != 0) { + r = ssh_get_publickey_hash(pubkey, type, &server_hash, &server_hash_len); + ssh_key_free(pubkey); + if (r != 0) { + session_error_setg(errp, s, + "failed reading the hash of the server SSH key"); + return -EINVAL; + } + + r = compare_fingerprint(server_hash, server_hash_len, hash); + ssh_clean_pubkey_hash(&server_hash); + if (r != 0) { error_setg(errp, "remote host key does not match host_key_check '%s'", hash); return -EPERM; @@ -431,8 +401,7 @@ check_host_key_hash(BDRVSSHState *s, const char *hash, return 0; } -static int check_host_key(BDRVSSHState *s, const char *host, int port, - SshHostKeyCheck *hkc, Error **errp) +static int check_host_key(BDRVSSHState *s, SshHostKeyCheck *hkc, Error **errp) { SshHostKeyCheckMode mode; @@ -448,15 +417,15 @@ static int check_host_key(BDRVSSHState *s, const char *host, int port, case SSH_HOST_KEY_CHECK_MODE_HASH: if (hkc->u.hash.type == SSH_HOST_KEY_CHECK_HASH_TYPE_MD5) { return check_host_key_hash(s, hkc->u.hash.hash, - LIBSSH2_HOSTKEY_HASH_MD5, 16, errp); + SSH_PUBLICKEY_HASH_MD5, errp); } else if (hkc->u.hash.type == SSH_HOST_KEY_CHECK_HASH_TYPE_SHA1) { return check_host_key_hash(s, hkc->u.hash.hash, - LIBSSH2_HOSTKEY_HASH_SHA1, 20, errp); + SSH_PUBLICKEY_HASH_SHA1, errp); } g_assert_not_reached(); break; case SSH_HOST_KEY_CHECK_MODE_KNOWN_HOSTS: - return check_host_key_knownhosts(s, host, port, errp); + return check_host_key_knownhosts(s, errp); default: g_assert_not_reached(); } @@ -464,60 +433,41 @@ static int check_host_key(BDRVSSHState *s, const char *host, int port, return -EINVAL; } -static int authenticate(BDRVSSHState *s, const char *user, Error **errp) +static int authenticate(BDRVSSHState *s, Error **errp) { int r, ret; - const char *userauthlist; - LIBSSH2_AGENT *agent = NULL; - struct libssh2_agent_publickey *identity; - struct libssh2_agent_publickey *prev_identity = NULL; + int method; - userauthlist = libssh2_userauth_list(s->session, user, strlen(user)); - if (strstr(userauthlist, "publickey") == NULL) { + /* Try to authenticate with the "none" method. */ + r = ssh_userauth_none(s->session, NULL); + if (r == SSH_AUTH_ERROR) { ret = -EPERM; - error_setg(errp, - "remote server does not support \"publickey\" authentication"); + session_error_setg(errp, s, "failed to authenticate using none " + "authentication"); goto out; - } - - /* Connect to ssh-agent and try each identity in turn. */ - agent = libssh2_agent_init(s->session); - if (!agent) { - ret = -EINVAL; - session_error_setg(errp, s, "failed to initialize ssh-agent support"); - goto out; - } - if (libssh2_agent_connect(agent)) { - ret = -ECONNREFUSED; - session_error_setg(errp, s, "failed to connect to ssh-agent"); - goto out; - } - if (libssh2_agent_list_identities(agent)) { - ret = -EINVAL; - session_error_setg(errp, s, - "failed requesting identities from ssh-agent"); + } else if (r == SSH_AUTH_SUCCESS) { + /* Authenticated! */ + ret = 0; goto out; } - for(;;) { - r = libssh2_agent_get_identity(agent, &identity, prev_identity); - if (r == 1) { /* end of list */ - break; - } - if (r < 0) { + method = ssh_userauth_list(s->session, NULL); + + /* Try to authenticate with publickey, using the ssh-agent + * if available. + */ + if (method & SSH_AUTH_METHOD_PUBLICKEY) { + r = ssh_userauth_publickey_auto(s->session, NULL, NULL); + if (r == SSH_AUTH_ERROR) { ret = -EINVAL; - session_error_setg(errp, s, - "failed to obtain identity from ssh-agent"); + session_error_setg(errp, s, "failed to authenticate using " + "publickey authentication"); goto out; - } - r = libssh2_agent_userauth(agent, user, identity); - if (r == 0) { + } else if (r == SSH_AUTH_SUCCESS) { /* Authenticated! */ ret = 0; goto out; } - /* Failed to authenticate with this identity, try the next one. */ - prev_identity = identity; } ret = -EPERM; @@ -525,13 +475,6 @@ static int authenticate(BDRVSSHState *s, const char *user, Error **errp) "and the identities held by your ssh-agent"); out: - if (agent != NULL) { - /* Note: libssh2 implementation implicitly calls - * libssh2_agent_disconnect if necessary. - */ - libssh2_agent_free(agent); - } - return ret; } @@ -651,7 +594,8 @@ static int connect_to_ssh(BDRVSSHState *s, BlockdevOptionsSsh *opts, { int r, ret; const char *user; - long port = 0; + unsigned int port = 0; + int new_sock = -1; if (opts->has_user) { user = opts->user; @@ -668,54 +612,117 @@ static int connect_to_ssh(BDRVSSHState *s, BlockdevOptionsSsh *opts, s->inet = opts->server; opts->server = NULL; - if (qemu_strtol(s->inet->port, NULL, 10, &port) < 0) { + if (qemu_strtoui(s->inet->port, NULL, 10, &port) < 0) { error_setg(errp, "Use only numeric port value"); ret = -EINVAL; goto err; } /* Open the socket and connect. */ - s->sock = inet_connect_saddr(s->inet, errp); - if (s->sock < 0) { + new_sock = inet_connect_saddr(s->inet, errp); + if (new_sock < 0) { ret = -EIO; goto err; } + /* Try to disable the Nagle algorithm on TCP sockets to reduce latency, + * but do not fail if it cannot be disabled. + */ + r = socket_set_nodelay(new_sock); + if (r < 0) { + warn_report("setting NODELAY for the ssh server %s failed: %m", + s->inet->host); + } + /* Create SSH session. */ - s->session = libssh2_session_init(); + s->session = ssh_new(); if (!s->session) { ret = -EINVAL; - session_error_setg(errp, s, "failed to initialize libssh2 session"); + session_error_setg(errp, s, "failed to initialize libssh session"); goto err; } -#if TRACE_LIBSSH2 != 0 - libssh2_trace(s->session, TRACE_LIBSSH2); -#endif + /* Make sure we are in blocking mode during the connection and + * authentication phases. + */ + ssh_set_blocking(s->session, 1); - r = libssh2_session_handshake(s->session, s->sock); - if (r != 0) { + r = ssh_options_set(s->session, SSH_OPTIONS_USER, user); + if (r < 0) { + ret = -EINVAL; + session_error_setg(errp, s, + "failed to set the user in the libssh session"); + goto err; + } + + r = ssh_options_set(s->session, SSH_OPTIONS_HOST, s->inet->host); + if (r < 0) { + ret = -EINVAL; + session_error_setg(errp, s, + "failed to set the host in the libssh session"); + goto err; + } + + if (port > 0) { + r = ssh_options_set(s->session, SSH_OPTIONS_PORT, &port); + if (r < 0) { + ret = -EINVAL; + session_error_setg(errp, s, + "failed to set the port in the libssh session"); + goto err; + } + } + + /* Read ~/.ssh/config. */ + r = ssh_options_parse_config(s->session, NULL); + if (r < 0) { + ret = -EINVAL; + session_error_setg(errp, s, "failed to parse ~/.ssh/config"); + goto err; + } + + r = ssh_options_set(s->session, SSH_OPTIONS_FD, &new_sock); + if (r < 0) { + ret = -EINVAL; + session_error_setg(errp, s, + "failed to set the socket in the libssh session"); + goto err; + } + /* libssh took ownership of the socket. */ + s->sock = new_sock; + new_sock = -1; + + /* Connect. */ + r = ssh_connect(s->session); + if (r != SSH_OK) { ret = -EINVAL; session_error_setg(errp, s, "failed to establish SSH session"); goto err; } /* Check the remote host's key against known_hosts. */ - ret = check_host_key(s, s->inet->host, port, opts->host_key_check, errp); + ret = check_host_key(s, opts->host_key_check, errp); if (ret < 0) { goto err; } /* Authenticate. */ - ret = authenticate(s, user, errp); + ret = authenticate(s, errp); if (ret < 0) { goto err; } /* Start SFTP. */ - s->sftp = libssh2_sftp_init(s->session); + s->sftp = sftp_new(s->session); if (!s->sftp) { - session_error_setg(errp, s, "failed to initialize sftp handle"); + session_error_setg(errp, s, "failed to create sftp handle"); + ret = -EINVAL; + goto err; + } + + r = sftp_init(s->sftp); + if (r < 0) { + sftp_error_setg(errp, s, "failed to initialize sftp handle"); ret = -EINVAL; goto err; } @@ -723,17 +730,19 @@ static int connect_to_ssh(BDRVSSHState *s, BlockdevOptionsSsh *opts, /* Open the remote file. */ DPRINTF("opening file %s flags=0x%x creat_mode=0%o", opts->path, ssh_flags, creat_mode); - s->sftp_handle = libssh2_sftp_open(s->sftp, opts->path, ssh_flags, - creat_mode); + s->sftp_handle = sftp_open(s->sftp, opts->path, ssh_flags, creat_mode); if (!s->sftp_handle) { - session_error_setg(errp, s, "failed to open remote file '%s'", - opts->path); + sftp_error_setg(errp, s, "failed to open remote file '%s'", + opts->path); ret = -EINVAL; goto err; } - r = libssh2_sftp_fstat(s->sftp_handle, &s->attrs); - if (r < 0) { + /* Make sure the SFTP file is handled in blocking mode. */ + sftp_file_set_blocking(s->sftp_handle); + + s->attrs = sftp_fstat(s->sftp_handle); + if (!s->attrs) { sftp_error_setg(errp, s, "failed to read file attributes"); return -EINVAL; } @@ -741,21 +750,26 @@ static int connect_to_ssh(BDRVSSHState *s, BlockdevOptionsSsh *opts, return 0; err: + if (s->attrs) { + sftp_attributes_free(s->attrs); + } + s->attrs = NULL; if (s->sftp_handle) { - libssh2_sftp_close(s->sftp_handle); + sftp_close(s->sftp_handle); } s->sftp_handle = NULL; if (s->sftp) { - libssh2_sftp_shutdown(s->sftp); + sftp_free(s->sftp); } s->sftp = NULL; if (s->session) { - libssh2_session_disconnect(s->session, - "from qemu ssh client: " - "error opening connection"); - libssh2_session_free(s->session); + ssh_disconnect(s->session); + ssh_free(s->session); } s->session = NULL; + if (new_sock >= 0) { + close(new_sock); + } return ret; } @@ -770,9 +784,11 @@ static int ssh_file_open(BlockDriverState *bs, QDict *options, int bdrv_flags, ssh_state_init(s); - ssh_flags = LIBSSH2_FXF_READ; + ssh_flags = 0; if (bdrv_flags & BDRV_O_RDWR) { - ssh_flags |= LIBSSH2_FXF_WRITE; + ssh_flags |= O_RDWR; + } else { + ssh_flags |= O_RDONLY; } opts = ssh_parse_options(options, errp); @@ -787,16 +803,13 @@ static int ssh_file_open(BlockDriverState *bs, QDict *options, int bdrv_flags, } /* Go non-blocking. */ - libssh2_session_set_blocking(s->session, 0); + ssh_set_blocking(s->session, 0); qapi_free_BlockdevOptionsSsh(opts); return 0; err: - if (s->sock >= 0) { - close(s->sock); - } s->sock = -1; qapi_free_BlockdevOptionsSsh(opts); @@ -809,25 +822,25 @@ static int ssh_grow_file(BDRVSSHState *s, int64_t offset, Error **errp) { ssize_t ret; char c[1] = { '\0' }; - int was_blocking = libssh2_session_get_blocking(s->session); + int was_blocking = ssh_is_blocking(s->session); /* offset must be strictly greater than the current size so we do * not overwrite anything */ - assert(offset > 0 && offset > s->attrs.filesize); + assert(offset > 0 && offset > s->attrs->size); - libssh2_session_set_blocking(s->session, 1); + ssh_set_blocking(s->session, 1); - libssh2_sftp_seek64(s->sftp_handle, offset - 1); - ret = libssh2_sftp_write(s->sftp_handle, c, 1); + sftp_seek64(s->sftp_handle, offset - 1); + ret = sftp_write(s->sftp_handle, c, 1); - libssh2_session_set_blocking(s->session, was_blocking); + ssh_set_blocking(s->session, was_blocking); if (ret < 0) { sftp_error_setg(errp, s, "Failed to grow file"); return -EIO; } - s->attrs.filesize = offset; + s->attrs->size = offset; return 0; } @@ -855,8 +868,7 @@ static int ssh_co_create(BlockdevCreateOptions *options, Error **errp) ssh_state_init(&s); ret = connect_to_ssh(&s, opts->location, - LIBSSH2_FXF_READ|LIBSSH2_FXF_WRITE| - LIBSSH2_FXF_CREAT|LIBSSH2_FXF_TRUNC, + O_RDWR | O_CREAT | O_TRUNC, 0644, errp); if (ret < 0) { goto fail; @@ -925,10 +937,8 @@ static int ssh_has_zero_init(BlockDriverState *bs) /* Assume false, unless we can positively prove it's true. */ int has_zero_init = 0; - if (s->attrs.flags & LIBSSH2_SFTP_ATTR_PERMISSIONS) { - if (s->attrs.permissions & LIBSSH2_SFTP_S_IFREG) { - has_zero_init = 1; - } + if (s->attrs->type == SSH_FILEXFER_TYPE_REGULAR) { + has_zero_init = 1; } return has_zero_init; @@ -965,12 +975,12 @@ static coroutine_fn void co_yield(BDRVSSHState *s, BlockDriverState *bs) .co = qemu_coroutine_self() }; - r = libssh2_session_block_directions(s->session); + r = ssh_get_poll_flags(s->session); - if (r & LIBSSH2_SESSION_BLOCK_INBOUND) { + if (r & SSH_READ_PENDING) { rd_handler = restart_coroutine; } - if (r & LIBSSH2_SESSION_BLOCK_OUTBOUND) { + if (r & SSH_WRITE_PENDING) { wr_handler = restart_coroutine; } @@ -983,33 +993,6 @@ static coroutine_fn void co_yield(BDRVSSHState *s, BlockDriverState *bs) DPRINTF("s->sock=%d - back", s->sock); } -/* SFTP has a function `libssh2_sftp_seek64' which seeks to a position - * in the remote file. Notice that it just updates a field in the - * sftp_handle structure, so there is no network traffic and it cannot - * fail. - * - * However, `libssh2_sftp_seek64' does have a catastrophic effect on - * performance since it causes the handle to throw away all in-flight - * reads and buffered readahead data. Therefore this function tries - * to be intelligent about when to call the underlying libssh2 function. - */ -#define SSH_SEEK_WRITE 0 -#define SSH_SEEK_READ 1 -#define SSH_SEEK_FORCE 2 - -static void ssh_seek(BDRVSSHState *s, int64_t offset, int flags) -{ - bool op_read = (flags & SSH_SEEK_READ) != 0; - bool force = (flags & SSH_SEEK_FORCE) != 0; - - if (force || op_read != s->offset_op_read || offset != s->offset) { - DPRINTF("seeking to offset=%" PRIi64, offset); - libssh2_sftp_seek64(s->sftp_handle, offset); - s->offset = offset; - s->offset_op_read = op_read; - } -} - static coroutine_fn int ssh_read(BDRVSSHState *s, BlockDriverState *bs, int64_t offset, size_t size, QEMUIOVector *qiov) @@ -1021,7 +1004,7 @@ static coroutine_fn int ssh_read(BDRVSSHState *s, BlockDriverState *bs, DPRINTF("offset=%" PRIi64 " size=%zu", offset, size); - ssh_seek(s, offset, SSH_SEEK_READ); + sftp_seek64(s->sftp_handle, offset); /* This keeps track of the current iovec element ('i'), where we * will write to next ('buf'), and the end of the current iovec @@ -1031,35 +1014,34 @@ static coroutine_fn int ssh_read(BDRVSSHState *s, BlockDriverState *bs, buf = i->iov_base; end_of_vec = i->iov_base + i->iov_len; - /* libssh2 has a hard-coded limit of 2000 bytes per request, - * although it will also do readahead behind our backs. Therefore - * we may have to do repeated reads here until we have read 'size' - * bytes. - */ for (got = 0; got < size; ) { again: - DPRINTF("sftp_read buf=%p size=%zu", buf, end_of_vec - buf); - r = libssh2_sftp_read(s->sftp_handle, buf, end_of_vec - buf); - DPRINTF("sftp_read returned %zd", r); + DPRINTF("sftp_read buf=%p size=%zu (actual size=%zu)", + buf, end_of_vec - buf, MIN(end_of_vec - buf, 16384)); + /* The size of SFTP packets is limited to 32K bytes, so limit + * the amount of data requested to 16K, as libssh currently + * does not handle multiple requests on its own: + * https://red.libssh.org/issues/58 + */ + r = sftp_read(s->sftp_handle, buf, MIN(end_of_vec - buf, 16384)); + DPRINTF("sftp_read returned %zd/%d", r, sftp_get_error(s->sftp)); - if (r == LIBSSH2_ERROR_EAGAIN || r == LIBSSH2_ERROR_TIMEOUT) { + if (r == SSH_AGAIN) { co_yield(s, bs); goto again; } - if (r < 0) { - sftp_error_report(s, "read failed"); - s->offset = -1; - return -EIO; - } - if (r == 0) { + if (r == SSH_EOF || (r == 0 && sftp_get_error(s->sftp) == SSH_FX_EOF)) { /* EOF: Short read so pad the buffer with zeroes and return it. */ qemu_iovec_memset(qiov, got, 0, size - got); return 0; } + if (r <= 0) { + sftp_error_report(s, "read failed"); + return -EIO; + } got += r; buf += r; - s->offset += r; if (buf >= end_of_vec && got < size) { i++; buf = i->iov_base; @@ -1096,7 +1078,7 @@ static int ssh_write(BDRVSSHState *s, BlockDriverState *bs, DPRINTF("offset=%" PRIi64 " size=%zu", offset, size); - ssh_seek(s, offset, SSH_SEEK_WRITE); + sftp_seek64(s->sftp_handle, offset); /* This keeps track of the current iovec element ('i'), where we * will read from next ('buf'), and the end of the current iovec @@ -1108,45 +1090,35 @@ static int ssh_write(BDRVSSHState *s, BlockDriverState *bs, for (written = 0; written < size; ) { again: - DPRINTF("sftp_write buf=%p size=%zu", buf, end_of_vec - buf); - r = libssh2_sftp_write(s->sftp_handle, buf, end_of_vec - buf); - DPRINTF("sftp_write returned %zd", r); + DPRINTF("sftp_write buf=%p size=%zu (actual size=%zu)", + buf, end_of_vec - buf, MIN(end_of_vec - buf, 131072)); + /* Avoid too large data packets, as libssh currently does not + * handle multiple requests on its own: + * https://red.libssh.org/issues/58 + */ + r = sftp_write(s->sftp_handle, buf, MIN(end_of_vec - buf, 131072)); + DPRINTF("sftp_write returned %zd/%d", r, sftp_get_error(s->sftp)); - if (r == LIBSSH2_ERROR_EAGAIN || r == LIBSSH2_ERROR_TIMEOUT) { + if (r == SSH_AGAIN) { co_yield(s, bs); goto again; } if (r < 0) { sftp_error_report(s, "write failed"); - s->offset = -1; return -EIO; } - /* The libssh2 API is very unclear about this. A comment in - * the code says "nothing was acked, and no EAGAIN was - * received!" which apparently means that no data got sent - * out, and the underlying channel didn't return any EAGAIN - * indication. I think this is a bug in either libssh2 or - * OpenSSH (server-side). In any case, forcing a seek (to - * discard libssh2 internal buffers), and then trying again - * works for me. - */ - if (r == 0) { - ssh_seek(s, offset + written, SSH_SEEK_WRITE|SSH_SEEK_FORCE); - co_yield(s, bs); - goto again; - } written += r; buf += r; - s->offset += r; if (buf >= end_of_vec && written < size) { i++; buf = i->iov_base; end_of_vec = i->iov_base + i->iov_len; } - if (offset + written > s->attrs.filesize) - s->attrs.filesize = offset + written; + if (offset + written > s->attrs->size) { + s->attrs->size = offset + written; + } } return 0; @@ -1181,24 +1153,24 @@ static void unsafe_flush_warning(BDRVSSHState *s, const char *what) } } -#ifdef HAS_LIBSSH2_SFTP_FSYNC +#ifdef HAS_LIBSSH_SFTP_FSYNC static coroutine_fn int ssh_flush(BDRVSSHState *s, BlockDriverState *bs) { int r; DPRINTF("fsync"); + + if (!sftp_extension_supported(s->sftp, "fs...@openssh.com", "1")) { + unsafe_flush_warning(s, "OpenSSH >= 6.3"); + return 0; + } again: - r = libssh2_sftp_fsync(s->sftp_handle); - if (r == LIBSSH2_ERROR_EAGAIN || r == LIBSSH2_ERROR_TIMEOUT) { + r = sftp_fsync(s->sftp_handle); + if (r == SSH_AGAIN) { co_yield(s, bs); goto again; } - if (r == LIBSSH2_ERROR_SFTP_PROTOCOL && - libssh2_sftp_last_error(s->sftp) == LIBSSH2_FX_OP_UNSUPPORTED) { - unsafe_flush_warning(s, "OpenSSH >= 6.3"); - return 0; - } if (r < 0) { sftp_error_report(s, "fsync failed"); return -EIO; @@ -1219,25 +1191,25 @@ static coroutine_fn int ssh_co_flush(BlockDriverState *bs) return ret; } -#else /* !HAS_LIBSSH2_SFTP_FSYNC */ +#else /* !HAS_LIBSSH_SFTP_FSYNC */ static coroutine_fn int ssh_co_flush(BlockDriverState *bs) { BDRVSSHState *s = bs->opaque; - unsafe_flush_warning(s, "libssh2 >= 1.4.4"); + unsafe_flush_warning(s, "libssh >= 0.8.0"); return 0; } -#endif /* !HAS_LIBSSH2_SFTP_FSYNC */ +#endif /* !HAS_LIBSSH_SFTP_FSYNC */ static int64_t ssh_getlength(BlockDriverState *bs) { BDRVSSHState *s = bs->opaque; int64_t length; - /* Note we cannot make a libssh2 call here. */ - length = (int64_t) s->attrs.filesize; + /* Note we cannot make a libssh call here. */ + length = (int64_t) s->attrs->size; DPRINTF("length=%" PRIi64, length); return length; @@ -1254,12 +1226,12 @@ static int ssh_truncate(BlockDriverState *bs, int64_t offset, return -ENOTSUP; } - if (offset < s->attrs.filesize) { + if (offset < s->attrs->size) { error_setg(errp, "ssh driver does not support shrinking files"); return -ENOTSUP; } - if (offset == s->attrs.filesize) { + if (offset == s->attrs->size) { return 0; } @@ -1288,12 +1260,16 @@ static void bdrv_ssh_init(void) { int r; - r = libssh2_init(0); + r = ssh_init(); if (r != 0) { - fprintf(stderr, "libssh2 initialization failed, %d\n", r); + fprintf(stderr, "libssh initialization failed, %d\n", r); exit(EXIT_FAILURE); } +#if TRACE_LIBSSH != 0 + ssh_set_log_level(TRACE_LIBSSH); +#endif + bdrv_register(&bdrv_ssh); } diff --git a/configure b/configure index 4d12cfbe3f..9d24fa9087 100755 --- a/configure +++ b/configure @@ -447,7 +447,7 @@ gcrypt_kdf="no" vte="" virglrenderer="" tpm="yes" -libssh2="" +libssh="" live_block_migration="yes" numa="" tcmalloc="no" @@ -1357,9 +1357,9 @@ for opt do ;; --enable-tpm) tpm="yes" ;; - --disable-libssh2) libssh2="no" + --disable-libssh) libssh="no" ;; - --enable-libssh2) libssh2="yes" + --enable-libssh) libssh="yes" ;; --disable-live-block-migration) live_block_migration="no" ;; @@ -1669,7 +1669,7 @@ disabled with --disable-FEATURE, default is enabled if available: coroutine-pool coroutine freelist (better performance) glusterfs GlusterFS backend tpm TPM support - libssh2 ssh block device support + libssh ssh block device support numa libnuma support libxml2 for Parallels image format tcmalloc tcmalloc support @@ -3665,43 +3665,42 @@ EOF fi ########################################## -# libssh2 probe -min_libssh2_version=1.2.8 -if test "$libssh2" != "no" ; then - if $pkg_config --atleast-version=$min_libssh2_version libssh2; then - libssh2_cflags=$($pkg_config libssh2 --cflags) - libssh2_libs=$($pkg_config libssh2 --libs) - libssh2=yes +# libssh probe +if test "$libssh" != "no" ; then + if $pkg_config --exists libssh; then + libssh_cflags=$($pkg_config libssh --cflags) + libssh_libs=$($pkg_config libssh --libs) + libssh=yes else - if test "$libssh2" = "yes" ; then - error_exit "libssh2 >= $min_libssh2_version required for --enable-libssh2" + if test "$libssh" = "yes" ; then + error_exit "libssh required for --enable-libssh" fi - libssh2=no + libssh=no fi fi ########################################## -# libssh2_sftp_fsync probe +# libssh sftp_fsync probe -if test "$libssh2" = "yes"; then +if test "$libssh" = "yes"; then cat > $TMPC <<EOF #include <stdio.h> -#include <libssh2.h> -#include <libssh2_sftp.h> +#include <libssh/libssh.h> +#include <libssh/sftp.h> int main(void) { - LIBSSH2_SESSION *session; - LIBSSH2_SFTP *sftp; - LIBSSH2_SFTP_HANDLE *sftp_handle; - session = libssh2_session_init (); - sftp = libssh2_sftp_init (session); - sftp_handle = libssh2_sftp_open (sftp, "/", 0, 0); - libssh2_sftp_fsync (sftp_handle); + ssh_session session; + sftp_session sftp; + sftp_file sftp_handle; + session = ssh_new(); + sftp = sftp_new(session); + sftp_handle = sftp_open(sftp, "/", 0, 0); + sftp_fsync(sftp_handle); return 0; } EOF - # libssh2_cflags/libssh2_libs defined in previous test. - if compile_prog "$libssh2_cflags" "$libssh2_libs" ; then - QEMU_CFLAGS="-DHAS_LIBSSH2_SFTP_FSYNC $QEMU_CFLAGS" + # libssh_cflags/libssh_libs defined in previous test. + if compile_prog "$libssh_cflags" "$libssh_libs" ; then + QEMU_CFLAGS="-DHAS_LIBSSH_SFTP_FSYNC $QEMU_CFLAGS" fi fi @@ -5956,7 +5955,7 @@ echo "GlusterFS support $glusterfs" echo "gcov $gcov_tool" echo "gcov enabled $gcov" echo "TPM support $tpm" -echo "libssh2 support $libssh2" +echo "libssh support $libssh" echo "TPM passthrough $tpm_passthrough" echo "TPM emulator $tpm_emulator" echo "QOM debugging $qom_cast_debug" @@ -6604,10 +6603,10 @@ if test "$glusterfs_zerofill" = "yes" ; then echo "CONFIG_GLUSTERFS_ZEROFILL=y" >> $config_host_mak fi -if test "$libssh2" = "yes" ; then - echo "CONFIG_LIBSSH2=m" >> $config_host_mak - echo "LIBSSH2_CFLAGS=$libssh2_cflags" >> $config_host_mak - echo "LIBSSH2_LIBS=$libssh2_libs" >> $config_host_mak +if test "$libssh" = "yes" ; then + echo "CONFIG_LIBSSH=m" >> $config_host_mak + echo "LIBSSH_CFLAGS=$libssh_cflags" >> $config_host_mak + echo "LIBSSH_LIBS=$libssh_libs" >> $config_host_mak fi if test "$live_block_migration" = "yes" ; then diff --git a/tests/qemu-iotests/207.out b/tests/qemu-iotests/207.out index 078b7e63cb..566a4f35e6 100644 --- a/tests/qemu-iotests/207.out +++ b/tests/qemu-iotests/207.out @@ -68,7 +68,7 @@ virtual size: 4.0M (4194304 bytes) {'execute': 'blockdev-create', 'arguments': {'job_id': 'job0', 'options': {'driver': 'ssh', 'location': {'path': '/this/is/not/an/existing/path', 'host-key-check': {'mode': 'none'}, 'server': {'host': '127.0.0.1', 'port': '22'}}, 'size': 4194304}}} {u'return': {}} -Job failed: failed to open remote file '/this/is/not/an/existing/path': Failed opening remote file (libssh2 error code: -31) +Job failed: failed to open remote file '/this/is/not/an/existing/path': SFTP server: No such file (libssh error code: 1, sftp error code: 2) {'execute': 'job-dismiss', 'arguments': {'id': 'job0'}} {u'return': {}} -- 2.17.1
