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-rw-r--r--comm/third_party/libotr/toolkit/parse.c654
1 files changed, 654 insertions, 0 deletions
diff --git a/comm/third_party/libotr/toolkit/parse.c b/comm/third_party/libotr/toolkit/parse.c
new file mode 100644
index 0000000000..aaa0ad59c9
--- /dev/null
+++ b/comm/third_party/libotr/toolkit/parse.c
@@ -0,0 +1,654 @@
+/*
+ * Off-the-Record Messaging Toolkit
+ * Copyright (C) 2004-2012 Ian Goldberg, Rob Smits, Chris Alexander,
+ * Nikita Borisov
+ * <otr@cypherpunks.ca>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * 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
+ */
+
+/* system headers */
+#include <stdio.h>
+#include <stdlib.h>
+
+/* libotr headers */
+#include "b64.h"
+
+/* toolkit headers */
+#include "sha1hmac.h"
+#include "parse.h"
+
+/* Dump an unsigned int to a FILE * */
+void dump_int(FILE *stream, const char *title, unsigned int val)
+{
+ fprintf(stream, "%s: %u\n", title, val);
+}
+
+/* Dump an mpi to a FILE * */
+void dump_mpi(FILE *stream, const char *title, gcry_mpi_t val)
+{
+ size_t plen;
+ unsigned char *d;
+
+ gcry_mpi_print(GCRYMPI_FMT_USG, NULL, 0, &plen, val);
+ d = malloc(plen);
+ gcry_mpi_print(GCRYMPI_FMT_USG, d, plen, NULL, val);
+ dump_data(stream, title, d, plen);
+ free(d);
+}
+
+/* Dump data to a FILE * */
+void dump_data(FILE *stream, const char *title, const unsigned char *data,
+ size_t datalen)
+{
+ size_t i;
+ fprintf(stream, "%s: ", title);
+ for(i=0;i<datalen;++i) {
+ fprintf(stream, "%02x", data[i]);
+ }
+ fprintf(stream, "\n");
+}
+
+/* base64 decode the message, and put the resulting size into *lenp */
+static unsigned char *decode(const char *msg, size_t *lenp)
+{
+ const char *header, *footer;
+ unsigned char *raw;
+ size_t rawlen;
+
+ /* Find the header */
+ header = strstr(msg, "?OTR:");
+ if (!header) return NULL;
+ /* Skip the header */
+ header += 5;
+
+ /* Find the trailing '.' */
+ footer = strchr(header, '.');
+ if (!footer) footer = header + strlen(header);
+
+ rawlen = OTRL_B64_MAX_DECODED_SIZE(footer-header);
+
+ raw = malloc(rawlen);
+ if (raw == NULL && rawlen > 0) return NULL;
+ *lenp = otrl_base64_decode(raw, header, footer-header);
+
+ return raw;
+}
+
+#define require_len(l) do { if (lenp < (l)) goto inv; } while(0)
+#define read_int(x) do { \
+ require_len(4); \
+ (x) = (((unsigned int)bufp[0]) << 24) | (bufp[1] << 16) | (bufp[2] << 8 ) | bufp[3]; \
+ bufp += 4; lenp -= 4; \
+ } while(0)
+#define read_mpi(x) do { \
+ size_t mpilen; \
+ read_int(mpilen); \
+ require_len(mpilen); \
+ gcry_mpi_scan(&(x), GCRYMPI_FMT_USG, bufp, mpilen, NULL); \
+ bufp += mpilen; lenp -= mpilen; \
+ } while(0)
+#define read_raw(b, l) do { \
+ if (l) { \
+ require_len(l); \
+ memmove((b), bufp, (l)); \
+ bufp += (l); lenp -= (l); \
+ } \
+ } while(0)
+#define write_int(x) do { \
+ bufp[0] = ((x) >> 24) & 0xff; \
+ bufp[1] = ((x) >> 16) & 0xff; \
+ bufp[2] = ((x) >> 8) & 0xff; \
+ bufp[3] = (x) & 0xff; \
+ bufp += 4; lenp -= 4; \
+ } while(0)
+#define write_mpi(x,l) do { \
+ write_int(l); \
+ gcry_mpi_print(GCRYMPI_FMT_USG, bufp, lenp, NULL, (x)); \
+ bufp += (l); lenp -= (l); \
+ } while(0)
+#define write_raw(x,l) do { \
+ memmove(bufp, (x), (l)); \
+ bufp += (l); lenp -= (l); \
+ } while(0)
+
+/* Parse a Key Exchange Message into a newly-allocated KeyExchMsg structure */
+KeyExchMsg parse_keyexch(const char *msg)
+{
+ KeyExchMsg kem = NULL;
+ size_t lenp;
+ unsigned char *raw = decode(msg, &lenp);
+ unsigned char *bufp = raw;
+ if (!raw) goto inv;
+
+ kem = calloc(1, sizeof(struct s_KeyExchMsg));
+ if (!kem) {
+ free(raw);
+ goto inv;
+ }
+
+ kem->raw = raw;
+ kem->sigstart = bufp;
+
+ require_len(3);
+ if (memcmp(bufp, "\x00\x01\x0a", 3)) goto inv;
+ bufp += 3; lenp -= 3;
+
+ require_len(1);
+ kem->reply = *bufp;
+ bufp += 1; lenp -= 1;
+
+ read_mpi(kem->p);
+ read_mpi(kem->q);
+ read_mpi(kem->g);
+ read_mpi(kem->e);
+
+ read_int(kem->keyid);
+
+ read_mpi(kem->y);
+
+ kem->sigend = bufp;
+
+ require_len(40);
+ gcry_mpi_scan(&kem->r, GCRYMPI_FMT_USG, bufp, 20, NULL);
+ gcry_mpi_scan(&kem->s, GCRYMPI_FMT_USG, bufp+20, 20, NULL);
+ bufp += 40; lenp -= 40;
+
+ if (lenp != 0) goto inv;
+
+ return kem;
+inv:
+ free_keyexch(kem);
+ return NULL;
+}
+
+/* Deallocate a KeyExchMsg and all of the data it points to */
+void free_keyexch(KeyExchMsg keyexch)
+{
+ if (!keyexch) return;
+ free(keyexch->raw);
+ gcry_mpi_release(keyexch->p);
+ gcry_mpi_release(keyexch->q);
+ gcry_mpi_release(keyexch->g);
+ gcry_mpi_release(keyexch->e);
+ gcry_mpi_release(keyexch->y);
+ gcry_mpi_release(keyexch->r);
+ gcry_mpi_release(keyexch->s);
+ free(keyexch);
+}
+
+/* Parse a D-H Commit Message into a newly-allocated CommitMsg structure */
+CommitMsg parse_commit(const char *msg)
+{
+ CommitMsg cmsg = NULL;
+ size_t lenp;
+ unsigned char *raw = decode(msg, &lenp);
+ unsigned char *bufp = raw;
+ if (!raw) goto inv;
+
+ cmsg = calloc(1, sizeof(struct s_CommitMsg));
+ if (!cmsg) {
+ free(raw);
+ goto inv;
+ }
+
+ cmsg->raw = raw;
+
+ require_len(3);
+
+ cmsg->version = bufp[1];
+
+ if (!memcmp(bufp, "\x00\x03\x02", 3)) {
+ bufp += 3; lenp -= 3;
+ read_int(cmsg->sender_instance);
+ read_int(cmsg->receiver_instance);
+ } else if (!memcmp(bufp, "\x00\x02\x02", 3)) {
+ bufp += 3; lenp -= 3;
+ cmsg->sender_instance = 0;
+ cmsg->receiver_instance = 0;
+ } else goto inv;
+
+ read_int(cmsg->enckeylen);
+ cmsg->enckey = malloc(cmsg->enckeylen);
+ if (!cmsg->enckey && cmsg->enckeylen > 0) goto inv;
+ read_raw(cmsg->enckey, cmsg->enckeylen);
+
+ read_int(cmsg->hashkeylen);
+ cmsg->hashkey = malloc(cmsg->hashkeylen);
+ if (!cmsg->hashkey && cmsg->hashkeylen > 0) goto inv;
+ read_raw(cmsg->hashkey, cmsg->hashkeylen);
+
+ if (lenp != 0) goto inv;
+
+ return cmsg;
+inv:
+ free_commit(cmsg);
+ return NULL;
+}
+
+/* Deallocate a CommitMsg and all of the data it points to */
+void free_commit(CommitMsg cmsg)
+{
+ if (!cmsg) return;
+ free(cmsg->raw);
+ free(cmsg->enckey);
+ free(cmsg->hashkey);
+ free(cmsg);
+}
+
+/* Parse a D-H Key Message into a newly-allocated KeyMsg structure */
+KeyMsg parse_key(const char *msg)
+{
+ KeyMsg kmsg = NULL;
+ size_t lenp;
+ unsigned char *raw = decode(msg, &lenp);
+ unsigned char *bufp = raw;
+ if (!raw) goto inv;
+
+ kmsg = calloc(1, sizeof(struct s_KeyMsg));
+ if (!kmsg) {
+ free(raw);
+ goto inv;
+ }
+
+ kmsg->raw = raw;
+
+ require_len(3);
+
+ kmsg->version = bufp[1];
+
+ if (!memcmp(bufp, "\x00\x03\x0a", 3)) {
+ bufp += 3; lenp -= 3;
+ read_int(kmsg->sender_instance);
+ read_int(kmsg->receiver_instance);
+ } else if (!memcmp(bufp, "\x00\x02\x0a", 3)) {
+ bufp += 3; lenp -= 3;
+ kmsg->sender_instance = 0;
+ kmsg->receiver_instance = 0;
+ } else goto inv;
+
+ read_mpi(kmsg->y);
+
+ if (lenp != 0) goto inv;
+
+ return kmsg;
+inv:
+ free_key(kmsg);
+ return NULL;
+}
+
+/* Deallocate a KeyMsg and all of the data it points to */
+void free_key(KeyMsg kmsg)
+{
+ if (!kmsg) return;
+ free(kmsg->raw);
+ gcry_mpi_release(kmsg->y);
+ free(kmsg);
+}
+
+/* Parse a Reveal Signature Message into a newly-allocated RevealSigMsg
+ * structure */
+RevealSigMsg parse_revealsig(const char *msg)
+{
+ RevealSigMsg rmsg = NULL;
+ size_t lenp;
+ unsigned char *raw = decode(msg, &lenp);
+ unsigned char *bufp = raw;
+ if (!raw) goto inv;
+
+ rmsg = calloc(1, sizeof(struct s_RevealSigMsg));
+ if (!rmsg) {
+ free(raw);
+ goto inv;
+ }
+
+ rmsg->raw = raw;
+
+ require_len(3);
+
+ rmsg->version = bufp[1];
+
+ if (!memcmp(bufp, "\x00\x03\x11", 3)) {
+ bufp += 3; lenp -= 3;
+ read_int(rmsg->sender_instance);
+ read_int(rmsg->receiver_instance);
+ } else if (!memcmp(bufp, "\x00\x02\x11", 3)) {
+ bufp += 3; lenp -= 3;
+ rmsg->sender_instance = 0;
+ rmsg->receiver_instance = 0;
+ } else goto inv;
+
+ read_int(rmsg->keylen);
+ rmsg->key = malloc(rmsg->keylen);
+ if (!rmsg->key && rmsg->keylen > 0) goto inv;
+ read_raw(rmsg->key, rmsg->keylen);
+
+ read_int(rmsg->encsiglen);
+ rmsg->encsig = malloc(rmsg->encsiglen);
+ if (!rmsg->encsig && rmsg->encsiglen > 0) goto inv;
+ read_raw(rmsg->encsig, rmsg->encsiglen);
+
+ read_raw(rmsg->mac, 20);
+
+ if (lenp != 0) goto inv;
+
+ return rmsg;
+inv:
+ free_revealsig(rmsg);
+ return NULL;
+}
+
+/* Deallocate a RevealSigMsg and all of the data it points to */
+void free_revealsig(RevealSigMsg rmsg)
+{
+ if (!rmsg) return;
+ free(rmsg->raw);
+ free(rmsg->key);
+ free(rmsg->encsig);
+ free(rmsg);
+}
+
+/* Parse a Signature Message into a newly-allocated SignatureMsg structure */
+SignatureMsg parse_signature(const char *msg)
+{
+ SignatureMsg smsg = NULL;
+ size_t lenp;
+ unsigned char *raw = decode(msg, &lenp);
+ unsigned char *bufp = raw;
+ if (!raw) goto inv;
+
+ smsg = calloc(1, sizeof(struct s_SignatureMsg));
+ if (!smsg) {
+ free(raw);
+ goto inv;
+ }
+
+ smsg->raw = raw;
+
+ require_len(3);
+
+ smsg->version = bufp[1];
+
+ if (!memcmp(bufp, "\x00\x03\x12", 3)) {
+ bufp += 3; lenp -= 3;
+ read_int(smsg->sender_instance);
+ read_int(smsg->receiver_instance);
+ } else if (!memcmp(bufp, "\x00\x02\x12", 3)) {
+ bufp += 3; lenp -= 3;
+ smsg->sender_instance = 0;
+ smsg->receiver_instance = 0;
+ } else goto inv;
+
+ read_int(smsg->encsiglen);
+ smsg->encsig = malloc(smsg->encsiglen);
+ if (!smsg->encsig && smsg->encsiglen > 0) goto inv;
+ read_raw(smsg->encsig, smsg->encsiglen);
+
+ read_raw(smsg->mac, 20);
+
+ if (lenp != 0) goto inv;
+
+ return smsg;
+inv:
+ free_signature(smsg);
+ return NULL;
+}
+
+/* Deallocate a SignatureMsg and all of the data it points to */
+void free_signature(SignatureMsg smsg)
+{
+ if (!smsg) return;
+ free(smsg->raw);
+ free(smsg->encsig);
+ free(smsg);
+}
+
+/* Parse a Data Message into a newly-allocated DataMsg structure */
+DataMsg parse_datamsg(const char *msg)
+{
+ DataMsg datam = NULL;
+ size_t lenp;
+ unsigned char *raw = decode(msg, &lenp);
+ unsigned char *bufp = raw;
+ unsigned char version;
+ if (!raw) goto inv;
+
+ datam = calloc(1, sizeof(struct s_DataMsg));
+ if (!datam) {
+ free(raw);
+ goto inv;
+ }
+
+ datam->raw = raw;
+ datam->rawlen = lenp;
+ datam->macstart = bufp;
+
+ require_len(3);
+ if (memcmp(bufp, "\x00\x01\x03", 3) && memcmp(bufp, "\x00\x03\x03", 3) &&
+ memcmp(bufp, "\x00\x02\x03", 3)) goto inv;
+
+ version = bufp[1];
+
+ datam->sender_instance = 0;
+ datam->receiver_instance = 0;
+ datam->version = version;
+ datam->flags = -1;
+ bufp += 3; lenp -= 3;
+
+ if (version == 3) {
+ read_int(datam->sender_instance);
+ read_int(datam->receiver_instance);
+ }
+
+ if (version == 2 || version == 3) {
+ require_len(1);
+ datam->flags = bufp[0];
+ bufp += 1; lenp -= 1;
+ }
+
+ read_int(datam->sender_keyid);
+ read_int(datam->rcpt_keyid);
+ read_mpi(datam->y);
+ read_raw(datam->ctr, 8);
+ read_int(datam->encmsglen);
+ datam->encmsg = malloc(datam->encmsglen);
+ if (!datam->encmsg && datam->encmsglen > 0) goto inv;
+ read_raw(datam->encmsg, datam->encmsglen);
+ datam->macend = bufp;
+ read_raw(datam->mac, 20);
+ read_int(datam->mackeyslen);
+ datam->mackeys = malloc(datam->mackeyslen);
+
+ if (!datam->mackeys && datam->mackeyslen > 0) goto inv;
+
+ read_raw(datam->mackeys, datam->mackeyslen);
+ if (lenp != 0) goto inv;
+
+ return datam;
+inv:
+ free_datamsg(datam);
+ return NULL;
+}
+
+/* Recalculate the MAC on the message, base64-encode the resulting MAC'd
+ * message, and put on the appropriate header and footer. Return a
+ * newly-allocated pointer to the result, which the caller will have to
+ * free(). */
+char *remac_datamsg(DataMsg datamsg, unsigned char mackey[20])
+{
+ size_t rawlen, lenp;
+ size_t ylen;
+ size_t base64len;
+ char *outmsg;
+ unsigned char *raw, *bufp;
+ unsigned char version = datamsg->version;
+
+ /* Calculate the size of the message that will result */
+ gcry_mpi_print(GCRYMPI_FMT_USG, NULL, 0, &ylen, datamsg->y);
+ rawlen = 3 + (version == 3 ? 8 : 0) + (version == 2 ||
+ version == 3 ? 1 : 0) + 4 + 4 + 4 + ylen + 8 + 4 +
+ datamsg->encmsglen + 20 + 4 + datamsg->mackeyslen;
+
+ /* Construct the new raw message (note that some of the pieces may
+ * have been altered, so we construct it from scratch). */
+ raw = malloc(rawlen);
+ if (!raw) {
+ fprintf(stderr, "Out of memory!\n");
+ exit(1);
+ }
+ bufp = raw;
+ lenp = rawlen;
+ datamsg->macstart = raw;
+ datamsg->macend = NULL;
+ free(datamsg->raw);
+ datamsg->raw = raw;
+ datamsg->rawlen = rawlen;
+
+
+ memmove(bufp, "\x00", 1);
+ memmove(bufp+1, &version, 1);
+ memmove(bufp+2, "\x03", 1);
+ bufp += 3; lenp -= 3;
+
+ if (version == 3) {
+ write_int(datamsg->sender_instance);
+ write_int(datamsg->receiver_instance);
+ }
+
+ if (version == 2 || version == 3) {
+ bufp[0] = datamsg->flags;
+ bufp += 1; lenp -= 1;
+ }
+
+ write_int(datamsg->sender_keyid);
+ write_int(datamsg->rcpt_keyid);
+ write_mpi(datamsg->y, ylen);
+ write_raw(datamsg->ctr, 8);
+ write_int(datamsg->encmsglen);
+ write_raw(datamsg->encmsg, datamsg->encmsglen);
+ datamsg->macend = bufp;
+
+ /* Recalculate the MAC */
+ sha1hmac(datamsg->mac, mackey, datamsg->macstart,
+ datamsg->macend - datamsg->macstart);
+
+ write_raw(datamsg->mac, 20);
+ write_int(datamsg->mackeyslen);
+ write_raw(datamsg->mackeys, datamsg->mackeyslen);
+
+ if (lenp != 0) {
+ fprintf(stderr, "Error creating OTR Data Message.\n");
+ exit(1);
+ }
+
+ base64len = 5 + ((datamsg->rawlen + 2) / 3) * 4 + 1 + 1;
+ outmsg = malloc(base64len);
+ if (!outmsg) return NULL;
+
+ memmove(outmsg, "?OTR:", 5);
+ otrl_base64_encode(outmsg + 5, datamsg->raw, datamsg->rawlen);
+ strcpy(outmsg + base64len - 2, ".");
+ return outmsg;
+}
+
+/* Assemble a new Data Message from its pieces. Return a
+ * newly-allocated string containing the base64 representation. */
+char *assemble_datamsg(unsigned char mackey[20],
+ unsigned char version, unsigned int sender_instance,
+ unsigned int receiver_instance, int flags, unsigned int sender_keyid,
+ unsigned int rcpt_keyid, gcry_mpi_t y,
+ unsigned char ctr[8], unsigned char *encmsg, size_t encmsglen,
+ unsigned char *mackeys, size_t mackeyslen)
+{
+ DataMsg datam = calloc(1, sizeof(struct s_DataMsg));
+ char *newmsg = NULL;
+ if (!datam) goto inv;
+ datam->version = version;
+ datam->flags = flags;
+ datam->sender_instance = sender_instance;
+ datam->receiver_instance = receiver_instance;
+ datam->sender_keyid = sender_keyid;
+ datam->rcpt_keyid = rcpt_keyid;
+ datam->y = gcry_mpi_copy(y);
+ memmove(datam->ctr, ctr, 8);
+ datam->encmsg = malloc(encmsglen);
+ if (!datam->encmsg && encmsglen > 0) goto inv;
+ memmove(datam->encmsg, encmsg, encmsglen);
+ datam->encmsglen = encmsglen;
+ datam->mackeys = malloc(mackeyslen);
+ if (!datam->mackeys && mackeyslen > 0) goto inv;
+ memmove(datam->mackeys, mackeys, mackeyslen);
+ datam->mackeyslen = mackeyslen;
+
+ /* Recalculate the MAC and base64-encode the result */
+ newmsg = remac_datamsg(datam, mackey);
+ free_datamsg(datam);
+ return newmsg;
+inv:
+ free_datamsg(datam);
+ return NULL;
+}
+
+/* Deallocate a DataMsg and all of the data it points to */
+void free_datamsg(DataMsg datamsg)
+{
+ if (!datamsg) return;
+ free(datamsg->raw);
+ gcry_mpi_release(datamsg->y);
+ free(datamsg->encmsg);
+ free(datamsg->mackeys);
+ free(datamsg);
+}
+
+static int ctoh(char c)
+{
+ if (c >= '0' && c <= '9') return (c-'0');
+ if (c >= 'a' && c <= 'f') return (c-'a'+10);
+ if (c >= 'A' && c <= 'F') return (c-'A'+10);
+ return -1;
+}
+
+/* Convert a string of hex chars to a buffer of unsigned chars. */
+void argv_to_buf(unsigned char **bufp, size_t *lenp, char *arg)
+{
+ unsigned char *buf;
+ size_t len, i;
+
+ *bufp = NULL;
+ *lenp = 0;
+
+ len = strlen(arg);
+ if (len % 2) {
+ fprintf(stderr, "Argument ``%s'' must have even length.\n", arg);
+ return;
+ }
+ buf = malloc(len/2);
+ if (buf == NULL && len > 0) {
+ fprintf(stderr, "Out of memory!\n");
+ return;
+ }
+
+ for(i=0;i<len/2;++i) {
+ int hi = ctoh(arg[2*i]);
+ int lo = ctoh(arg[2*i+1]);
+ if (hi < 0 || lo < 0) {
+ free(buf);
+ fprintf(stderr, "Illegal hex char in argument ``%s''.\n", arg);
+ return;
+ }
+ buf[i] = (hi << 4) + lo;
+ }
+ *bufp = buf;
+ *lenp = len/2;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-08 21:42:10 +0000