diff options
Diffstat (limited to 'g10/parse-packet.c')
| -rw-r--r-- | g10/parse-packet.c | 111 |
1 files changed, 103 insertions, 8 deletions
diff --git a/g10/parse-packet.c b/g10/parse-packet.c index fc37c095d..c3f6b544d 100644 --- a/g10/parse-packet.c +++ b/g10/parse-packet.c @@ -188,6 +188,76 @@ mpi_read (iobuf_t inp, unsigned int *ret_nread, int secure) } +/* Read an external representation of an SOS and return the opaque MPI + with GCRYMPI_FLAG_USER2. The external format is a 16-bit unsigned + value stored in network byte order giving information for the + following octets. + + The caller must set *RET_NREAD to the maximum number of bytes to + read from the pipeline INP. This function sets *RET_NREAD to be + the number of bytes actually read from the pipeline. + + If SECURE is true, the integer is stored in secure memory + (allocated using gcry_xmalloc_secure). */ +static gcry_mpi_t +sos_read (iobuf_t inp, unsigned int *ret_nread, int secure) +{ + int c, c1, c2, i; + unsigned int nmax = *ret_nread; + unsigned int nbits, nbytes; + size_t nread = 0; + gcry_mpi_t a = NULL; + byte *buf = NULL; + byte *p; + + if (!nmax) + goto overflow; + + if ((c = c1 = iobuf_get (inp)) == -1) + goto leave; + if (++nread == nmax) + goto overflow; + nbits = c << 8; + if ((c = c2 = iobuf_get (inp)) == -1) + goto leave; + ++nread; + nbits |= c; + if (nbits > MAX_EXTERN_MPI_BITS) + { + log_error ("mpi too large (%u bits)\n", nbits); + goto leave; + } + + nbytes = (nbits + 7) / 8; + buf = secure ? gcry_xmalloc_secure (nbytes) : gcry_xmalloc (nbytes); + p = buf; + for (i = 0; i < nbytes; i++) + { + if (nread == nmax) + goto overflow; + + c = iobuf_get (inp); + if (c == -1) + goto leave; + + p[i] = c; + nread ++; + } + + a = gcry_mpi_set_opaque (NULL, buf, nbits); + gcry_mpi_set_flag (a, GCRYMPI_FLAG_USER2); + *ret_nread = nread; + return a; + + overflow: + log_error ("mpi larger than indicated length (%u bits)\n", 8*nmax); + leave: + *ret_nread = nread; + gcry_free(buf); + return a; +} + + /* Register STRING as a known critical notation name. */ void register_known_notation (const char *string) @@ -1328,11 +1398,22 @@ parse_pubkeyenc (IOBUF inp, int pkttype, unsigned long pktlen, { for (i = 0; i < ndata; i++) { - if (k->pubkey_algo == PUBKEY_ALGO_ECDH && i == 1) + if (k->pubkey_algo == PUBKEY_ALGO_ECDH) { - size_t n; - rc = read_size_body (inp, pktlen, &n, k->data+i); - pktlen -= n; + if (i == 1) + { + size_t n; + rc = read_size_body (inp, pktlen, &n, k->data+i); + pktlen -= n; + } + else + { + int n = pktlen; + k->data[i] = sos_read (inp, &n, 0); + pktlen -= n; + if (!k->data[i]) + rc = gpg_error (GPG_ERR_INV_PACKET); + } } else { @@ -2282,7 +2363,11 @@ parse_signature (IOBUF inp, int pkttype, unsigned long pktlen, for (i = 0; i < ndata; i++) { n = pktlen; - sig->data[i] = mpi_read (inp, &n, 0); + if (sig->pubkey_algo == PUBKEY_ALGO_ECDSA + || sig->pubkey_algo == PUBKEY_ALGO_EDDSA) + sig->data[i] = sos_read (inp, &n, 0); + else + sig->data[i] = mpi_read (inp, &n, 0); pktlen -= n; if (list_mode) { @@ -2510,7 +2595,7 @@ parse_key (IOBUF inp, int pkttype, unsigned long pktlen, || (algorithm == PUBKEY_ALGO_EDDSA && (i == 0)) || (algorithm == PUBKEY_ALGO_ECDH && (i == 0 || i == 2))) { - /* Read the OID (i==1) or the KDF params (i==2). */ + /* Read the OID (i==0) or the KDF params (i==2). */ size_t n; err = read_size_body (inp, pktlen, &n, pk->pkey+i); pktlen -= n; @@ -2518,7 +2603,12 @@ parse_key (IOBUF inp, int pkttype, unsigned long pktlen, else { unsigned int n = pktlen; - pk->pkey[i] = mpi_read (inp, &n, 0); + if (algorithm == PUBKEY_ALGO_ECDSA + || algorithm == PUBKEY_ALGO_EDDSA + || algorithm == PUBKEY_ALGO_ECDH) + pk->pkey[i] = sos_read (inp, &n, 0); + else + pk->pkey[i] = mpi_read (inp, &n, 0); pktlen -= n; if (!pk->pkey[i]) err = gpg_error (GPG_ERR_INV_PACKET); @@ -2830,7 +2920,12 @@ parse_key (IOBUF inp, int pkttype, unsigned long pktlen, goto leave; } n = pktlen; - pk->pkey[i] = mpi_read (inp, &n, 0); + if (algorithm == PUBKEY_ALGO_ECDSA + || algorithm == PUBKEY_ALGO_EDDSA + || algorithm == PUBKEY_ALGO_ECDH) + pk->pkey[i] = sos_read (inp, &n, 0); + else + pk->pkey[i] = mpi_read (inp, &n, 0); pktlen -= n; if (list_mode) { |