diff options
Diffstat (limited to 'src/rexmpp_jingle.c')
| -rw-r--r-- | src/rexmpp_jingle.c | 540 |
1 files changed, 540 insertions, 0 deletions
diff --git a/src/rexmpp_jingle.c b/src/rexmpp_jingle.c new file mode 100644 index 0000000..93dc628 --- /dev/null +++ b/src/rexmpp_jingle.c @@ -0,0 +1,540 @@ +/** + @file rexmpp_jingle.c + @brief Jingle routines + @author defanor <defanor@uberspace.net> + @date 2021 + @copyright MIT license. + +The following XEPs are handled here so far: + +- XEP-0166: Jingle +- XEP-0234: Jingle File Transfer +- XEP-0261: Jingle In-Band Bytestreams Transport Method +*/ + +#include <string.h> +#include <syslog.h> +#include <errno.h> +#include <libgen.h> +#include <gsasl.h> +#include <nettle/sha2.h> + +#include "rexmpp.h" +#include "rexmpp_jingle.h" + + +rexmpp_jingle_session_t * +rexmpp_jingle_session_by_id (rexmpp_t *s, const char *sid) { + if (sid == NULL) { + return NULL; + } + rexmpp_jingle_session_t *cur = s->jingle; + while (cur != NULL) { + if (strcmp(cur->sid, sid) == 0) { + return cur; + } + cur = cur->next; + } + rexmpp_log(s, LOG_WARNING, "No Jingle session with sid %s found", sid); + return NULL; +} + +rexmpp_jingle_session_t * +rexmpp_jingle_session_by_ibb_sid (rexmpp_t *s, const char *ibb_sid) { + if (ibb_sid == NULL) { + return NULL; + } + rexmpp_jingle_session_t *cur = s->jingle; + while (cur != NULL) { + if (strcmp(cur->ibb_sid, ibb_sid) == 0) { + return cur; + } + cur = cur->next; + } + rexmpp_log(s, LOG_WARNING, + "No Jingle session with ibb_sid %s found", ibb_sid); + return NULL; +} + +void rexmpp_jingle_session_destroy (rexmpp_jingle_session_t *session) { + if (session->jid != NULL) { + free(session->jid); + } + if (session->sid != NULL) { + free(session->sid); + } + if (session->negotiation != NULL) { + xmlFreeNodeList(session->negotiation); + } + if (session->f != NULL) { + fclose(session->f); + } + free(session); +} + +void rexmpp_jingle_session_delete (rexmpp_t *s, rexmpp_jingle_session_t *sess) { + if (sess == NULL) { + return; + } + rexmpp_log(s, LOG_DEBUG, "Removing Jingle session %s", sess->sid); + rexmpp_jingle_session_t **next_ptr = &(s->jingle), *cur = s->jingle; + while (cur != NULL) { + if (sess == cur) { + *next_ptr = cur->next; + rexmpp_jingle_session_destroy(sess); + } + next_ptr = &(cur->next); + cur = cur->next; + } +} + +void rexmpp_jingle_stop (rexmpp_t *s) { + while (s->jingle != NULL) { + rexmpp_jingle_session_delete(s, s->jingle); + } +} + +int rexmpp_jingle_session_add (rexmpp_t *s, rexmpp_jingle_session_t *sess) { + uint32_t sessions_num = 0; + rexmpp_jingle_session_t *cur = s->jingle; + while (cur != NULL) { + sessions_num++; + cur = cur->next; + } + if (sessions_num >= s->max_jingle_sessions) { + rexmpp_log(s, LOG_ERR, "Too many Jingle sessions, discaring a new one"); + rexmpp_jingle_session_destroy(sess); + return 0; + } + rexmpp_log(s, LOG_DEBUG, "Adding Jingle session %s", sess->sid); + sess->next = s->jingle; + s->jingle = sess; + return 1; +} + +void rexmpp_jingle_session_delete_by_id (rexmpp_t *s, const char *sid) { + rexmpp_jingle_session_delete(s, rexmpp_jingle_session_by_id(s, sid)); +} + + +void rexmpp_jingle_accept_file_cb (rexmpp_t *s, + void *ptr, + xmlNodePtr request, + xmlNodePtr response, + int success) +{ + (void)request; + (void)response; + char *sid = ptr; + if (! success) { + rexmpp_log(s, LOG_ERR, "Failed to accept a Jingle file transfer"); + rexmpp_jingle_session_delete_by_id(s, sid); + } + free(sid); +} + +rexmpp_err_t +rexmpp_jingle_accept_file (rexmpp_t *s, + rexmpp_jingle_session_t *session, + const char *path) +{ + session->f = fopen(path, "wb"); + if (session->f == NULL) { + rexmpp_log(s, LOG_ERR, "Failed to open %s for writing: %s", + path, strerror(errno)); + return REXMPP_E_OTHER; + } + xmlNodePtr jingle = session->negotiation; + xmlNodePtr content = rexmpp_xml_find_child(jingle, "urn:xmpp:jingle:1", "content"); + + xmlNodePtr new_jingle = rexmpp_xml_new_node("jingle", "urn:xmpp:jingle:1"); + xmlNewProp(new_jingle, "action", "session-accept"); + xmlNewProp(new_jingle, "responder", s->assigned_jid.full); + xmlNewProp(new_jingle, "sid", session->sid); + xmlAddChild(new_jingle, xmlCopyNode(content, 1)); + xmlFreeNode(session->negotiation); + session->negotiation = xmlCopyNode(new_jingle, 1); + return rexmpp_iq_new(s, "set", session->jid, new_jingle, + rexmpp_jingle_accept_file_cb, strdup(session->sid)); +} + +rexmpp_err_t +rexmpp_jingle_accept_file_by_id (rexmpp_t *s, + const char *sid, + const char *path) +{ + return + rexmpp_jingle_accept_file(s, rexmpp_jingle_session_by_id(s, sid), path); +} + +void rexmpp_jingle_session_terminate_cb (rexmpp_t *s, + void *ptr, + xmlNodePtr request, + xmlNodePtr response, + int success) +{ + (void)request; + (void)response; + char *sid = ptr; + if (! success) { + rexmpp_log(s, LOG_ERR, "Failed to terminate session %s, removing anyway", + sid); + } + rexmpp_jingle_session_delete_by_id(s, sid); + free(sid); +} + +rexmpp_err_t +rexmpp_jingle_session_terminate (rexmpp_t *s, + const char *sid, + xmlNodePtr reason_node, + const char *reason_text) +{ + rexmpp_jingle_session_t *session = rexmpp_jingle_session_by_id(s, sid); + if (session == NULL) { + return REXMPP_E_OTHER; + } + xmlNodePtr jingle = rexmpp_xml_new_node("jingle", "urn:xmpp:jingle:1"); + xmlNewProp(jingle, "action", "session-terminate"); + xmlNewProp(jingle, "sid", sid); + xmlNodePtr reason = rexmpp_xml_new_node("reason", "urn:xmpp:jingle:1"); + if (reason_text != NULL) { + xmlNodePtr text = rexmpp_xml_new_node("text", "urn:xmpp:jingle:1"); + xmlNodeAddContent(text, reason_text); + xmlAddChild(reason, text); + } + xmlAddChild(reason, reason_node); + xmlAddChild(jingle, reason); + return rexmpp_iq_new(s, "set", session->jid, jingle, + rexmpp_jingle_session_terminate_cb, strdup(sid)); +} + +rexmpp_err_t +rexmpp_jingle_accept_file_by_sid (rexmpp_t *s, + const char *sid, + const char *path) +{ + rexmpp_jingle_session_t *session = rexmpp_jingle_session_by_id(s, sid); + if (session == NULL) { + return REXMPP_E_OTHER; + } + return rexmpp_jingle_accept_file(s, session, path); +} + +void rexmpp_jingle_send_file_cb (rexmpp_t *s, + void *ptr, + xmlNodePtr request, + xmlNodePtr response, + int success) +{ + (void)request; + (void)response; + char *sid = ptr; + if (! success) { + rexmpp_log(s, LOG_ERR, "Failed to initiate file sending for sid %s", sid); + rexmpp_jingle_session_delete_by_id(s, sid); + } + free(sid); +} + +rexmpp_err_t +rexmpp_jingle_send_file (rexmpp_t *s, + const char *jid, + char *path) +{ + FILE *fh = fopen(path, "rb"); + if (fh == NULL) { + rexmpp_log(s, LOG_ERR, "Failed to open %s for reading", path); + return REXMPP_E_OTHER; + } + char *sid = rexmpp_gen_id(s); + char *ibb_sid = rexmpp_gen_id(s); + + xmlNodePtr jingle = rexmpp_xml_new_node("jingle", "urn:xmpp:jingle:1"); + xmlNewProp(jingle, "action", "session-initiate"); + xmlNewProp(jingle, "sid", sid); + xmlNewProp(jingle, "initiator", s->assigned_jid.full); + + xmlNodePtr content = rexmpp_xml_new_node("content", "urn:xmpp:jingle:1"); + xmlNewProp(content, "creator", "initiator"); + xmlNewProp(content, "name", "IBB file"); + xmlAddChild(jingle, content); + + xmlNodePtr transport = + rexmpp_xml_new_node("transport", "urn:xmpp:jingle:transports:ibb:1"); + xmlNewProp(transport, "block-size", "4096"); + xmlNewProp(transport, "sid", ibb_sid); + xmlAddChild(content, transport); + xmlNodePtr description = + rexmpp_xml_new_node("description", "urn:xmpp:jingle:apps:file-transfer:5"); + xmlAddChild(content, description); + xmlNodePtr file = + rexmpp_xml_new_node("file", "urn:xmpp:jingle:apps:file-transfer:5"); + xmlAddChild(description, file); + xmlNodePtr file_name = + rexmpp_xml_new_node("name", "urn:xmpp:jingle:apps:file-transfer:5"); + xmlNodeAddContent(file_name, basename(path)); + xmlAddChild(file, file_name); + + char buf[4096]; + + char hash_raw[SHA512_DIGEST_SIZE]; + struct sha512_ctx ctx; + sha512_init(&ctx); + size_t len = fread(buf, 1, 4096, fh); + while (len > 0) { + sha512_update(&ctx, len, buf); + len = fread(buf, 1, 4096, fh); + } + sha512_digest(&ctx, SHA512_DIGEST_SIZE, hash_raw); + char *hash_base64 = NULL; + size_t hash_base64_len = 0; + gsasl_base64_to(hash_raw, SHA512_DIGEST_SIZE, &hash_base64, &hash_base64_len); + xmlNodePtr file_hash = rexmpp_xml_new_node("hash", "urn:xmpp:hashes:2"); + xmlNewProp(file_hash, "algo", "sha-512"); + xmlNodeAddContent(file_hash, hash_base64); + free(hash_base64); + xmlAddChild(file, file_hash); + + long fsize = ftell(fh); + fseek(fh, 0, SEEK_SET); + snprintf(buf, 11, "%ld", fsize); + xmlNodePtr file_size = + rexmpp_xml_new_node("size", "urn:xmpp:jingle:apps:file-transfer:5"); + xmlNodeAddContent(file_size, buf); + xmlAddChild(file, file_size); + + rexmpp_jingle_session_t *sess = malloc(sizeof(rexmpp_jingle_session_t)); + sess->jid = strdup(jid); + sess->sid = sid; + sess->ibb_sid = ibb_sid; + sess->ibb_seq = 0; + sess->negotiation = xmlCopyNode(jingle, 1); + sess->f = fh; + if (rexmpp_jingle_session_add(s, sess)) { + return rexmpp_iq_new(s, "set", sess->jid, jingle, + rexmpp_jingle_send_file_cb, strdup(sess->sid)); + } else { + return REXMPP_E_OTHER; + } +} + +void rexmpp_jingle_close_cb (rexmpp_t *s, + void *ptr, + xmlNodePtr request, + xmlNodePtr response, + int success) +{ + (void)request; + (void)response; + char *sid = ptr; + if (success) { + rexmpp_log(s, LOG_DEBUG, "Closed IBB stream for Jingle stream %s", sid); + } else { + rexmpp_log(s, LOG_ERR, "Failed to close IBB stream for Jingle stream %s", sid); + } + free(sid); +} + +void rexmpp_jingle_send_cb (rexmpp_t *s, + void *ptr, + xmlNodePtr request, + xmlNodePtr response, + int success) +{ + (void)request; + (void)response; + char *sid = ptr; + if (! success) { + rexmpp_log(s, LOG_ERR, "An IBB stream error for Jingle sid %s", sid); + rexmpp_jingle_session_delete_by_id(s, sid); + free(sid); + return; + } + rexmpp_jingle_session_t *session = rexmpp_jingle_session_by_id(s, sid); + if (session == NULL) { + rexmpp_log(s, LOG_ERR, "Jingle session %s doesn't exist", sid); + free(sid); + return; + } + if (feof(session->f)) { + xmlNodePtr close = rexmpp_xml_new_node("close", "http://jabber.org/protocol/ibb"); + xmlNewProp(close, "sid", session->ibb_sid); + rexmpp_iq_new(s, "set", session->jid, close, + rexmpp_jingle_close_cb, sid); + return; + } else { + char buf[4096]; + size_t len = fread(buf, 1, 4096, session->f); + if (len > 0) { + xmlNodePtr data = rexmpp_xml_new_node("data", "http://jabber.org/protocol/ibb"); + xmlNewProp(data, "sid", session->ibb_sid); + char *out = NULL; + size_t out_len = 0; + gsasl_base64_to(buf, len, &out, &out_len); + xmlNodeAddContent(data, out); + free(out); + snprintf(buf, 11, "%u", session->ibb_seq); + xmlNewProp(data, "seq", buf); + session->ibb_seq++; + rexmpp_iq_new(s, "set", session->jid, data, + rexmpp_jingle_send_cb, sid); + return; + } else { + rexmpp_log(s, LOG_ERR, "Failed to read from a file: %s ", strerror(errno)); + rexmpp_jingle_session_terminate(s, sid, + rexmpp_xml_new_node("media-error", + "urn:xmpp:jingle:1"), + NULL); + } + } + free(sid); +} + +int rexmpp_jingle_iq (rexmpp_t *s, xmlNodePtr elem) { + int handled = 0; + if (! s->enable_jingle) { + return handled; + } + xmlNodePtr jingle = rexmpp_xml_find_child(elem, "urn:xmpp:jingle:1", "jingle"); + if (jingle != NULL) { + handled = 1; + char *action = xmlGetProp(jingle, "action"); + char *sid = xmlGetProp(jingle, "sid"); + char *from_jid = xmlGetProp(elem, "from"); + if (action != NULL && sid != NULL && from_jid != NULL) { + if (strcmp(action, "session-initiate") == 0) { + /* todo: could be more than one content element, handle that */ + xmlNodePtr content = rexmpp_xml_find_child(jingle, "urn:xmpp:jingle:1", "content"); + if (content == NULL) { + rexmpp_iq_reply(s, elem, "error", rexmpp_xml_error("cancel", "bad-request")); + } else { + rexmpp_iq_reply(s, elem, "result", NULL); + + xmlNodePtr description = + rexmpp_xml_find_child(content, "urn:xmpp:jingle:apps:file-transfer:5", + "description"); + xmlNodePtr transport = + rexmpp_xml_find_child(content, "urn:xmpp:jingle:transports:ibb:1", + "transport"); + if (description == NULL) { + rexmpp_jingle_session_terminate(s, sid, + rexmpp_xml_new_node("unsupported-applications", + "urn:xmpp:jingle:1"), + NULL); + } else if (transport == NULL) { + rexmpp_jingle_session_terminate(s, sid, + rexmpp_xml_new_node("unsupported-transports", + "urn:xmpp:jingle:1"), + NULL); + } else { + char *ibb_sid = xmlGetProp(transport, "sid"); + if (ibb_sid != NULL) { + rexmpp_jingle_session_t *sess = malloc(sizeof(rexmpp_jingle_session_t)); + sess->jid = strdup(from_jid); + sess->sid = strdup(sid); + sess->ibb_sid = ibb_sid; + sess->ibb_seq = 0; + sess->negotiation = xmlCopyNode(jingle, 1); + sess->f = NULL; + rexmpp_log(s, LOG_DEBUG, "Jingle session-initiate from %s, sid %s", + sess->jid, sid); + rexmpp_jingle_session_add(s, sess); + } else { + rexmpp_log(s, LOG_ERR, "Jingle IBB transport doesn't have a sid attribute"); + rexmpp_jingle_session_terminate(s, sid, + rexmpp_xml_new_node("unsupported-transports", + "urn:xmpp:jingle:1"), + NULL); + } + } + } + } else if (strcmp(action, "session-terminate") == 0) { + /* todo: check/log the reason */ + rexmpp_jingle_session_delete_by_id(s, sid); + rexmpp_iq_reply(s, elem, "result", NULL); + } else if (strcmp(action, "session-accept") == 0) { + rexmpp_iq_reply(s, elem, "result", NULL); + rexmpp_jingle_session_t *session = rexmpp_jingle_session_by_id(s, sid); + if (session != NULL) { + xmlNodePtr open = rexmpp_xml_new_node("open", "http://jabber.org/protocol/ibb"); + xmlNewProp(open, "sid", session->ibb_sid); + xmlNewProp(open, "block-size", "4096"); + xmlNewProp(open, "stanza", "iq"); + rexmpp_iq_new(s, "set", session->jid, open, + rexmpp_jingle_send_cb, strdup(sid)); + } + } else { + rexmpp_log(s, LOG_WARNING, "Unknown Jingle action: %s", action); + rexmpp_iq_reply(s, elem, "error", rexmpp_xml_error("cancel", "bad-request")); + } + } else { + rexmpp_log(s, LOG_WARNING, "Received a malformed Jingle element"); + rexmpp_iq_reply(s, elem, "error", rexmpp_xml_error("cancel", "bad-request")); + } + if (action != NULL) { + free(action); + } + if (sid != NULL) { + free(sid); + } + if (from_jid != NULL) { + free(from_jid); + } + } + + /* XEP-0261: Jingle In-Band Bytestreams Transport Method */ + xmlNodePtr ibb_open = rexmpp_xml_find_child(elem, "http://jabber.org/protocol/ibb", "open"); + if (ibb_open != NULL) { + handled = 1; + /* no-op, though could check sid here. */ + rexmpp_iq_reply(s, elem, "result", NULL); + } + xmlNodePtr ibb_close = rexmpp_xml_find_child(elem, "http://jabber.org/protocol/ibb", "close"); + if (ibb_close != NULL) { + handled = 1; + rexmpp_iq_reply(s, elem, "result", NULL); + char *sid = xmlGetProp(ibb_close, "sid"); + + if (sid != NULL) { + rexmpp_jingle_session_t *session = rexmpp_jingle_session_by_ibb_sid(s, sid); + if (session != NULL) { + rexmpp_jingle_session_terminate + (s, session->sid, + rexmpp_xml_new_node("success", "urn:xmpp:jingle:1"), NULL); + } + free(sid); + } + } + xmlNodePtr ibb_data = rexmpp_xml_find_child(elem, "http://jabber.org/protocol/ibb", "data"); + if (ibb_data != NULL) { + handled = 1; + char *sid = xmlGetProp(ibb_data, "sid"); + if (sid != NULL) { + rexmpp_jingle_session_t *session = rexmpp_jingle_session_by_ibb_sid(s, sid); + if (session != NULL && session->f != NULL) { + char *data = NULL, *data_base64 = xmlNodeGetContent(ibb_data); + if (data_base64 != NULL) { + size_t data_len = 0; + int sasl_err = gsasl_base64_from(data_base64, strlen(data_base64), + &data, &data_len); + free(data_base64); + if (sasl_err != GSASL_OK) { + rexmpp_log(s, LOG_ERR, "Base-64 decoding failure: %s", + gsasl_strerror(sasl_err)); + } else { + size_t written = fwrite(data, 1, data_len, session->f); + if (written != data_len) { + rexmpp_log(s, LOG_ERR, "Wrote %d bytes, expected %d", written, data_len); + /* todo: maybe introduce buffering, or make it an error */ + } + } + } + } + free(sid); + } + /* todo: report errors */ + rexmpp_iq_reply(s, elem, "result", NULL); + } + return handled; +} |