/src/openssl40/crypto/ec/ecp_oct.c

Source
/*
 * Copyright 2011-2025 The OpenSSL Project Authors. All Rights Reserved.
 * Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved
 *
 * Licensed under the Apache License 2.0 (the "License").  You may not use
 * this file except in compliance with the License.  You can obtain a copy
 * in the file LICENSE in the source distribution or at
 * https://www.openssl.org/source/license.html
 */

/*
 * ECDSA low level APIs are deprecated for public use, but still ok for
 * internal use.
 */
#include "internal/deprecated.h"

#include <openssl/err.h>
#include <openssl/symhacks.h>

#include "ec_local.h"

int ossl_ec_GFp_simple_set_compressed_coordinates(const EC_GROUP *group,
    EC_POINT *point,
    const BIGNUM *x_, int y_bit,
    BN_CTX *ctx)
{
    BN_CTX *new_ctx = NULL;
    BIGNUM *tmp1, *tmp2, *x, *y;
    int ret = 0;

    if (ctx == NULL) {
        ctx = new_ctx = BN_CTX_new_ex(group->libctx);
        if (ctx == NULL)
            return 0;
    }

    y_bit = (y_bit != 0);

    BN_CTX_start(ctx);
    tmp1 = BN_CTX_get(ctx);
    tmp2 = BN_CTX_get(ctx);
    x = BN_CTX_get(ctx);
    y = BN_CTX_get(ctx);
    if (y == NULL)
        goto err;

    /*-
     * Recover y.  We have a Weierstrass equation
     *     y^2 = x^3 + a*x + b,
     * so  y  is one of the square roots of  x^3 + a*x + b.
     */

    /* tmp1 := x^3 */
    if (!BN_nnmod(x, x_, group->field, ctx))
        goto err;
    if (group->meth->field_decode == 0) {
        /* field_{sqr,mul} work on standard representation */
        if (!group->meth->field_sqr(group, tmp2, x_, ctx))
            goto err;
        if (!group->meth->field_mul(group, tmp1, tmp2, x_, ctx))
            goto err;
    } else {
        if (!BN_mod_sqr(tmp2, x_, group->field, ctx))
            goto err;
        if (!BN_mod_mul(tmp1, tmp2, x_, group->field, ctx))
            goto err;
    }

    /* tmp1 := tmp1 + a*x */
    if (group->a_is_minus3) {
        if (!BN_mod_lshift1_quick(tmp2, x, group->field))
            goto err;
        if (!BN_mod_add_quick(tmp2, tmp2, x, group->field))
            goto err;
        if (!BN_mod_sub_quick(tmp1, tmp1, tmp2, group->field))
            goto err;
    } else {
        if (group->meth->field_decode) {
            if (!group->meth->field_decode(group, tmp2, group->a, ctx))
                goto err;
            if (!BN_mod_mul(tmp2, tmp2, x, group->field, ctx))
                goto err;
        } else {
            /* field_mul works on standard representation */
            if (!group->meth->field_mul(group, tmp2, group->a, x, ctx))
                goto err;
        }

        if (!BN_mod_add_quick(tmp1, tmp1, tmp2, group->field))
            goto err;
    }

    /* tmp1 := tmp1 + b */
    if (group->meth->field_decode) {
        if (!group->meth->field_decode(group, tmp2, group->b, ctx))
            goto err;
        if (!BN_mod_add_quick(tmp1, tmp1, tmp2, group->field))
            goto err;
    } else {
        if (!BN_mod_add_quick(tmp1, tmp1, group->b, group->field))
            goto err;
    }

    ERR_set_mark();
    if (!BN_mod_sqrt(y, tmp1, group->field, ctx)) {
#ifndef FIPS_MODULE
        unsigned long err = ERR_peek_last_error();

        if (ERR_GET_LIB(err) == ERR_LIB_BN
            && ERR_GET_REASON(err) == BN_R_NOT_A_SQUARE) {
            ERR_pop_to_mark();
            ERR_raise(ERR_LIB_EC, EC_R_INVALID_COMPRESSED_POINT);
        } else
#endif
        {
            ERR_clear_last_mark();
            ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
        }
        goto err;
    }
    ERR_clear_last_mark();

    if (y_bit != BN_is_odd(y)) {
        if (BN_is_zero(y)) {
            int kron;

            kron = BN_kronecker(x, group->field, ctx);
            if (kron == -2)
                goto err;

            if (kron == 1)
                ERR_raise(ERR_LIB_EC, EC_R_INVALID_COMPRESSION_BIT);
            else
                /*
                 * BN_mod_sqrt() should have caught this error (not a square)
                 */
                ERR_raise(ERR_LIB_EC, EC_R_INVALID_COMPRESSED_POINT);
            goto err;
        }
        if (!BN_usub(y, group->field, y))
            goto err;
    }
    if (y_bit != BN_is_odd(y)) {
        ERR_raise(ERR_LIB_EC, ERR_R_INTERNAL_ERROR);
        goto err;
    }

    if (!EC_POINT_set_affine_coordinates(group, point, x, y, ctx))
        goto err;

    ret = 1;

err:
    BN_CTX_end(ctx);
    BN_CTX_free(new_ctx);
    return ret;
}

size_t ossl_ec_GFp_simple_point2oct(const EC_GROUP *group, const EC_POINT *point,
    point_conversion_form_t form,
    unsigned char *buf, size_t len, BN_CTX *ctx)
{
    size_t ret;
    BN_CTX *new_ctx = NULL;
    int used_ctx = 0;
    BIGNUM *x, *y;
    size_t field_len, i, skip;

    if ((form != POINT_CONVERSION_COMPRESSED)
        && (form != POINT_CONVERSION_UNCOMPRESSED)
        && (form != POINT_CONVERSION_HYBRID)) {
        ERR_raise(ERR_LIB_EC, EC_R_INVALID_FORM);
        goto err;
    }

    if (EC_POINT_is_at_infinity(group, point)) {
        /* encodes to a single 0 octet */
        if (buf != NULL) {
            if (len < 1) {
                ERR_raise(ERR_LIB_EC, EC_R_BUFFER_TOO_SMALL);
                return 0;
            }
            buf[0] = 0;
        }
        return 1;
    }

    /* ret := required output buffer length */
    field_len = BN_num_bytes(group->field);
    ret = (form == POINT_CONVERSION_COMPRESSED) ? 1 + field_len : 1 + 2 * field_len;

    /* if 'buf' is NULL, just return required length */
    if (buf != NULL) {
        if (len < ret) {
            ERR_raise(ERR_LIB_EC, EC_R_BUFFER_TOO_SMALL);
            goto err;
        }

        if (ctx == NULL) {
            ctx = new_ctx = BN_CTX_new_ex(group->libctx);
            if (ctx == NULL)
                return 0;
        }

        BN_CTX_start(ctx);
        used_ctx = 1;
        x = BN_CTX_get(ctx);
        y = BN_CTX_get(ctx);
        if (y == NULL)
            goto err;

        if (!EC_POINT_get_affine_coordinates(group, point, x, y, ctx))
            goto err;

        if ((form == POINT_CONVERSION_COMPRESSED
                || form == POINT_CONVERSION_HYBRID)
            && BN_is_odd(y))
            buf[0] = form + 1;
        else
            buf[0] = form;

        i = 1;

        skip = field_len - BN_num_bytes(x);
        if (skip > field_len) {
            ERR_raise(ERR_LIB_EC, ERR_R_INTERNAL_ERROR);
            goto err;
        }
        while (skip > 0) {
            buf[i++] = 0;
            skip--;
        }
        skip = BN_bn2bin(x, buf + i);
        i += skip;
        if (i != 1 + field_len) {
            ERR_raise(ERR_LIB_EC, ERR_R_INTERNAL_ERROR);
            goto err;
        }

        if (form == POINT_CONVERSION_UNCOMPRESSED
            || form == POINT_CONVERSION_HYBRID) {
            skip = field_len - BN_num_bytes(y);
            if (skip > field_len) {
                ERR_raise(ERR_LIB_EC, ERR_R_INTERNAL_ERROR);
                goto err;
            }
            while (skip > 0) {
                buf[i++] = 0;
                skip--;
            }
            skip = BN_bn2bin(y, buf + i);
            i += skip;
        }

        if (i != ret) {
            ERR_raise(ERR_LIB_EC, ERR_R_INTERNAL_ERROR);
            goto err;
        }
    }

    if (used_ctx)
        BN_CTX_end(ctx);
    BN_CTX_free(new_ctx);
    return ret;

err:
    if (used_ctx)
        BN_CTX_end(ctx);
    BN_CTX_free(new_ctx);
    return 0;
}

int ossl_ec_GFp_simple_oct2point(const EC_GROUP *group, EC_POINT *point,
    const unsigned char *buf, size_t len,
    BN_CTX *ctx)
{
    point_conversion_form_t form;
    int y_bit;
    BN_CTX *new_ctx = NULL;
    BIGNUM *x, *y;
    int field_len, enc_len;
    int ret = 0;

    if (len == 0) {
        ERR_raise(ERR_LIB_EC, EC_R_BUFFER_TOO_SMALL);
        return 0;
    }
    form = buf[0];
    y_bit = form & 1;
    form = form & ~1U;
    if ((form != 0) && (form != POINT_CONVERSION_COMPRESSED)
        && (form != POINT_CONVERSION_UNCOMPRESSED)
        && (form != POINT_CONVERSION_HYBRID)) {
        ERR_raise(ERR_LIB_EC, EC_R_INVALID_ENCODING);
        return 0;
    }
    if ((form == 0 || form == POINT_CONVERSION_UNCOMPRESSED) && y_bit) {
        ERR_raise(ERR_LIB_EC, EC_R_INVALID_ENCODING);
        return 0;
    }

    if (form == 0) {
        if (len != 1) {
            ERR_raise(ERR_LIB_EC, EC_R_INVALID_ENCODING);
            return 0;
        }

        return EC_POINT_set_to_infinity(group, point);
    }

    field_len = BN_num_bytes(group->field);
    enc_len = (form == POINT_CONVERSION_COMPRESSED) ? 1 + field_len : 1 + 2 * field_len;

    if (len != (size_t)enc_len) {
        ERR_raise(ERR_LIB_EC, EC_R_INVALID_ENCODING);
        return 0;
    }

    if (ctx == NULL) {
        ctx = new_ctx = BN_CTX_new_ex(group->libctx);
        if (ctx == NULL)
            return 0;
    }

    BN_CTX_start(ctx);
    x = BN_CTX_get(ctx);
    y = BN_CTX_get(ctx);
    if (y == NULL)
        goto err;

    if (!BN_bin2bn(buf + 1, field_len, x))
        goto err;
    if (BN_ucmp(x, group->field) >= 0) {
        ERR_raise(ERR_LIB_EC, EC_R_INVALID_ENCODING);
        goto err;
    }

    if (form == POINT_CONVERSION_COMPRESSED) {
        if (!EC_POINT_set_compressed_coordinates(group, point, x, y_bit, ctx))
            goto err;
    } else {
        if (!BN_bin2bn(buf + 1 + field_len, field_len, y))
            goto err;
        if (BN_ucmp(y, group->field) >= 0) {
            ERR_raise(ERR_LIB_EC, EC_R_INVALID_ENCODING);
            goto err;
        }
        if (form == POINT_CONVERSION_HYBRID) {
            if (y_bit != BN_is_odd(y)) {
                ERR_raise(ERR_LIB_EC, EC_R_INVALID_ENCODING);
                goto err;
            }
        }

        /*
         * EC_POINT_set_affine_coordinates is responsible for checking that
         * the point is on the curve.
         */
        if (!EC_POINT_set_affine_coordinates(group, point, x, y, ctx))
            goto err;
    }

    ret = 1;

err:
    BN_CTX_end(ctx);
    BN_CTX_free(new_ctx);
    return ret;
}

Coverage Report

Created: 2026-09-12 06:55

Line	Count	Source
1		/*
2		* Copyright 2011-2025 The OpenSSL Project Authors. All Rights Reserved.
3		* Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved
4		*
5		* Licensed under the Apache License 2.0 (the "License"). You may not use
6		* this file except in compliance with the License. You can obtain a copy
7		* in the file LICENSE in the source distribution or at
8		* https://www.openssl.org/source/license.html
9		*/
10
11		/*
12		* ECDSA low level APIs are deprecated for public use, but still ok for
13		* internal use.
14		*/
15		#include "internal/deprecated.h"
16
17		#include <openssl/err.h>
18		#include <openssl/symhacks.h>
19
20		#include "ec_local.h"
21
22		int ossl_ec_GFp_simple_set_compressed_coordinates(const EC_GROUP *group,
23		EC_POINT *point,
24		const BIGNUM *x_, int y_bit,
25		BN_CTX *ctx)
26	156k	{
27	156k	BN_CTX *new_ctx = NULL;
28	156k	BIGNUM tmp1, tmp2, x, y;
29	156k	int ret = 0;
30
31	156k	if (ctx == NULL) {
32	0	ctx = new_ctx = BN_CTX_new_ex(group->libctx);
33	0	if (ctx == NULL)
34	0	return 0;
35	0	}
36
37	156k	y_bit = (y_bit != 0);
38
39	156k	BN_CTX_start(ctx);
40	156k	tmp1 = BN_CTX_get(ctx);
41	156k	tmp2 = BN_CTX_get(ctx);
42	156k	x = BN_CTX_get(ctx);
43	156k	y = BN_CTX_get(ctx);
44	156k	if (y == NULL)
45	0	goto err;
46
47		/*-
48		* Recover y. We have a Weierstrass equation
49		* y^2 = x^3 + a*x + b,
50		* so y is one of the square roots of x^3 + a*x + b.
51		*/
52
53		/* tmp1 := x^3 */
54	156k	if (!BN_nnmod(x, x_, group->field, ctx))
55	0	goto err;
56	156k	if (group->meth->field_decode == 0) {
57		/* field_{sqr,mul} work on standard representation */
58	65.1k	if (!group->meth->field_sqr(group, tmp2, x_, ctx))
59	0	goto err;
60	65.1k	if (!group->meth->field_mul(group, tmp1, tmp2, x_, ctx))
61	0	goto err;
62	91.3k	} else {
63	91.3k	if (!BN_mod_sqr(tmp2, x_, group->field, ctx))
64	0	goto err;
65	91.3k	if (!BN_mod_mul(tmp1, tmp2, x_, group->field, ctx))
66	0	goto err;
67	91.3k	}
68
69		/* tmp1 := tmp1 + ax /
70	156k	if (group->a_is_minus3) {
71	111k	if (!BN_mod_lshift1_quick(tmp2, x, group->field))
72	0	goto err;
73	111k	if (!BN_mod_add_quick(tmp2, tmp2, x, group->field))
74	0	goto err;
75	111k	if (!BN_mod_sub_quick(tmp1, tmp1, tmp2, group->field))
76	0	goto err;
77	111k	} else {
78	44.5k	if (group->meth->field_decode) {
79	44.5k	if (!group->meth->field_decode(group, tmp2, group->a, ctx))
80	0	goto err;
81	44.5k	if (!BN_mod_mul(tmp2, tmp2, x, group->field, ctx))
82	0	goto err;
83	44.5k	} else {
84		/* field_mul works on standard representation */
85	0	if (!group->meth->field_mul(group, tmp2, group->a, x, ctx))
86	0	goto err;
87	0	}
88
89	44.5k	if (!BN_mod_add_quick(tmp1, tmp1, tmp2, group->field))
90	0	goto err;
91	44.5k	}
92
93		/* tmp1 := tmp1 + b */
94	156k	if (group->meth->field_decode) {
95	91.3k	if (!group->meth->field_decode(group, tmp2, group->b, ctx))
96	0	goto err;
97	91.3k	if (!BN_mod_add_quick(tmp1, tmp1, tmp2, group->field))
98	0	goto err;
99	91.3k	} else {
100	65.1k	if (!BN_mod_add_quick(tmp1, tmp1, group->b, group->field))
101	0	goto err;
102	65.1k	}
103
104	156k	ERR_set_mark();
105	156k	if (!BN_mod_sqrt(y, tmp1, group->field, ctx)) {
106	55.0k	#ifndef FIPS_MODULE
107	55.0k	unsigned long err = ERR_peek_last_error();
108
109	55.0k	if (ERR_GET_LIB(err) == ERR_LIB_BN
110	55.0k	&& ERR_GET_REASON(err) == BN_R_NOT_A_SQUARE) {
111	54.5k	ERR_pop_to_mark();
112	54.5k	ERR_raise(ERR_LIB_EC, EC_R_INVALID_COMPRESSED_POINT);
113	54.5k	} else
114	558	#endif
115	558	{
116	558	ERR_clear_last_mark();
117	558	ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
118	558	}
119	55.0k	goto err;
120	55.0k	}
121	101k	ERR_clear_last_mark();
122
123	101k	if (y_bit != BN_is_odd(y)) {
124	53.9k	if (BN_is_zero(y)) {
125	123	int kron;
126
127	123	kron = BN_kronecker(x, group->field, ctx);
128	123	if (kron == -2)
129	0	goto err;
130
131	123	if (kron == 1)
132	123	ERR_raise(ERR_LIB_EC, EC_R_INVALID_COMPRESSION_BIT);
133	123	else
134		/*
135		* BN_mod_sqrt() should have caught this error (not a square)
136		*/
137	123	ERR_raise(ERR_LIB_EC, EC_R_INVALID_COMPRESSED_POINT);
138	123	goto err;
139	123	}
140	53.8k	if (!BN_usub(y, group->field, y))
141	0	goto err;
142	53.8k	}
143	101k	if (y_bit != BN_is_odd(y)) {
144	0	ERR_raise(ERR_LIB_EC, ERR_R_INTERNAL_ERROR);
145	0	goto err;
146	0	}
147
148	101k	if (!EC_POINT_set_affine_coordinates(group, point, x, y, ctx))
149	0	goto err;
150
151	101k	ret = 1;
152
153	156k	err:
154	156k	BN_CTX_end(ctx);
155	156k	BN_CTX_free(new_ctx);
156	156k	return ret;
157	101k	}
158
159		size_t ossl_ec_GFp_simple_point2oct(const EC_GROUP group, const EC_POINT point,
160		point_conversion_form_t form,
161		unsigned char buf, size_t len, BN_CTX ctx)
162	158k	{
163	158k	size_t ret;
164	158k	BN_CTX *new_ctx = NULL;
165	158k	int used_ctx = 0;
166	158k	BIGNUM x, y;
167	158k	size_t field_len, i, skip;
168
169	158k	if ((form != POINT_CONVERSION_COMPRESSED)
170	144k	&& (form != POINT_CONVERSION_UNCOMPRESSED)
171	414	&& (form != POINT_CONVERSION_HYBRID)) {
172	210	ERR_raise(ERR_LIB_EC, EC_R_INVALID_FORM);
173	210	goto err;
174	210	}
175
176	158k	if (EC_POINT_is_at_infinity(group, point)) {
177		/* encodes to a single 0 octet */
178	1.13k	if (buf != NULL) {
179	569	if (len < 1) {
180	0	ERR_raise(ERR_LIB_EC, EC_R_BUFFER_TOO_SMALL);
181	0	return 0;
182	0	}
183	569	buf[0] = 0;
184	569	}
185	1.13k	return 1;
186	1.13k	}
187
188		/* ret := required output buffer length */
189	157k	field_len = BN_num_bytes(group->field);
190	157k	ret = (form == POINT_CONVERSION_COMPRESSED) ? 1 + field_len : 1 + 2 * field_len;
191
192		/* if 'buf' is NULL, just return required length */
193	157k	if (buf != NULL) {
194	78.5k	if (len < ret) {
195	0	ERR_raise(ERR_LIB_EC, EC_R_BUFFER_TOO_SMALL);
196	0	goto err;
197	0	}
198
199	78.5k	if (ctx == NULL) {
200	10.2k	ctx = new_ctx = BN_CTX_new_ex(group->libctx);
201	10.2k	if (ctx == NULL)
202	0	return 0;
203	10.2k	}
204
205	78.5k	BN_CTX_start(ctx);
206	78.5k	used_ctx = 1;
207	78.5k	x = BN_CTX_get(ctx);
208	78.5k	y = BN_CTX_get(ctx);
209	78.5k	if (y == NULL)
210	0	goto err;
211
212	78.5k	if (!EC_POINT_get_affine_coordinates(group, point, x, y, ctx))
213	0	goto err;
214
215	78.5k	if ((form == POINT_CONVERSION_COMPRESSED
216	71.6k	\|\| form == POINT_CONVERSION_HYBRID)
217	7.07k	&& BN_is_odd(y))
218	2.84k	buf[0] = form + 1;
219	75.7k	else
220	75.7k	buf[0] = form;
221
222	78.5k	i = 1;
223
224	78.5k	skip = field_len - BN_num_bytes(x);
225	78.5k	if (skip > field_len) {
226	0	ERR_raise(ERR_LIB_EC, ERR_R_INTERNAL_ERROR);
227	0	goto err;
228	0	}
229	140k	while (skip > 0) {
230	61.6k	buf[i++] = 0;
231	61.6k	skip--;
232	61.6k	}
233	78.5k	skip = BN_bn2bin(x, buf + i);
234	78.5k	i += skip;
235	78.5k	if (i != 1 + field_len) {
236	0	ERR_raise(ERR_LIB_EC, ERR_R_INTERNAL_ERROR);
237	0	goto err;
238	0	}
239
240	78.5k	if (form == POINT_CONVERSION_UNCOMPRESSED
241	71.6k	\|\| form == POINT_CONVERSION_HYBRID) {
242	71.6k	skip = field_len - BN_num_bytes(y);
243	71.6k	if (skip > field_len) {
244	0	ERR_raise(ERR_LIB_EC, ERR_R_INTERNAL_ERROR);
245	0	goto err;
246	0	}
247	79.9k	while (skip > 0) {
248	8.37k	buf[i++] = 0;
249	8.37k	skip--;
250	8.37k	}
251	71.6k	skip = BN_bn2bin(y, buf + i);
252	71.6k	i += skip;
253	71.6k	}
254
255	78.5k	if (i != ret) {
256	0	ERR_raise(ERR_LIB_EC, ERR_R_INTERNAL_ERROR);
257	0	goto err;
258	0	}
259	78.5k	}
260
261	157k	if (used_ctx)
262	78.5k	BN_CTX_end(ctx);
263	157k	BN_CTX_free(new_ctx);
264	157k	return ret;
265
266	210	err:
267	210	if (used_ctx)
268	0	BN_CTX_end(ctx);
269	210	BN_CTX_free(new_ctx);
270	210	return 0;
271	157k	}
272
273		int ossl_ec_GFp_simple_oct2point(const EC_GROUP group, EC_POINT point,
274		const unsigned char *buf, size_t len,
275		BN_CTX *ctx)
276	377k	{
277	377k	point_conversion_form_t form;
278	377k	int y_bit;
279	377k	BN_CTX *new_ctx = NULL;
280	377k	BIGNUM x, y;
281	377k	int field_len, enc_len;
282	377k	int ret = 0;
283
284	377k	if (len == 0) {
285	20.8k	ERR_raise(ERR_LIB_EC, EC_R_BUFFER_TOO_SMALL);
286	20.8k	return 0;
287	20.8k	}
288	356k	form = buf[0];
289	356k	y_bit = form & 1;
290	356k	form = form & ~1U;
291	356k	if ((form != 0) && (form != POINT_CONVERSION_COMPRESSED)
292	173k	&& (form != POINT_CONVERSION_UNCOMPRESSED)
293	17.4k	&& (form != POINT_CONVERSION_HYBRID)) {
294	6.06k	ERR_raise(ERR_LIB_EC, EC_R_INVALID_ENCODING);
295	6.06k	return 0;
296	6.06k	}
297	350k	if ((form == 0 \|\| form == POINT_CONVERSION_UNCOMPRESSED) && y_bit) {
298	3.25k	ERR_raise(ERR_LIB_EC, EC_R_INVALID_ENCODING);
299	3.25k	return 0;
300	3.25k	}
301
302	347k	if (form == 0) {
303	16.0k	if (len != 1) {
304	7.26k	ERR_raise(ERR_LIB_EC, EC_R_INVALID_ENCODING);
305	7.26k	return 0;
306	7.26k	}
307
308	8.74k	return EC_POINT_set_to_infinity(group, point);
309	16.0k	}
310
311	331k	field_len = BN_num_bytes(group->field);
312	331k	enc_len = (form == POINT_CONVERSION_COMPRESSED) ? 1 + field_len : 1 + 2 * field_len;
313
314	331k	if (len != (size_t)enc_len) {
315	8.75k	ERR_raise(ERR_LIB_EC, EC_R_INVALID_ENCODING);
316	8.75k	return 0;
317	8.75k	}
318
319	322k	if (ctx == NULL) {
320	257k	ctx = new_ctx = BN_CTX_new_ex(group->libctx);
321	257k	if (ctx == NULL)
322	0	return 0;
323	257k	}
324
325	322k	BN_CTX_start(ctx);
326	322k	x = BN_CTX_get(ctx);
327	322k	y = BN_CTX_get(ctx);
328	322k	if (y == NULL)
329	0	goto err;
330
331	322k	if (!BN_bin2bn(buf + 1, field_len, x))
332	0	goto err;
333	322k	if (BN_ucmp(x, group->field) >= 0) {
334	4.69k	ERR_raise(ERR_LIB_EC, EC_R_INVALID_ENCODING);
335	4.69k	goto err;
336	4.69k	}
337
338	318k	if (form == POINT_CONVERSION_COMPRESSED) {
339	156k	if (!EC_POINT_set_compressed_coordinates(group, point, x, y_bit, ctx))
340	55.1k	goto err;
341	161k	} else {
342	161k	if (!BN_bin2bn(buf + 1 + field_len, field_len, y))
343	0	goto err;
344	161k	if (BN_ucmp(y, group->field) >= 0) {
345	419	ERR_raise(ERR_LIB_EC, EC_R_INVALID_ENCODING);
346	419	goto err;
347	419	}
348	161k	if (form == POINT_CONVERSION_HYBRID) {
349	7.07k	if (y_bit != BN_is_odd(y)) {
350	984	ERR_raise(ERR_LIB_EC, EC_R_INVALID_ENCODING);
351	984	goto err;
352	984	}
353	7.07k	}
354
355		/*
356		* EC_POINT_set_affine_coordinates is responsible for checking that
357		* the point is on the curve.
358		*/
359	160k	if (!EC_POINT_set_affine_coordinates(group, point, x, y, ctx))
360	14.6k	goto err;
361	160k	}
362
363	246k	ret = 1;
364
365	322k	err:
366	322k	BN_CTX_end(ctx);
367	322k	BN_CTX_free(new_ctx);
368	322k	return ret;
369	246k	}